Veterinary Files

ARTIFICIAL INSEMINATION

2010-08-13T16:17:00.000+07:00

Artificial insemination, or AI, is the process by which sperm is placed into the reproductive tract of a female for the purpose of impregnating the female by using means other than sexual intercourse or NI.

Artificial insemination is widely used for livestock breeding, especially for dairy cattle and pigs. Techniques developed for livestock have been adapted for use in humans.

Specifically, freshly ejaculated sperm, or sperm which has been frozen and thawed, is placed in the cervix (intracervical insemination – ICI) or, after washing, into the female's uterus (intrauterine insemination – IUI) by artificial means.

Artificial insemination is used in many non-human animals, including sheep, horses, cattle, pigs, dogs, pedigree animals generally, zoo animals, turkeys and even honeybees. It may be used for many reasons, including to allow a male to inseminate a much larger number of females, to allow use of genetic material from males separated by distance or time, to overcome physical breeding difficulties, to control the paternity of offspring, to synchronise births, to avoid injury incurred during natural mating, and to avoid the need to keep a male at all (such as for small numbers of females or in species whose fertile males may be difficult to manage).

Semen is collected, extended, then cooled or frozen. It can be used on site or shipped to the female's location. If frozen, the small plastic tube holding the semen is referred to as a straw. To allow the sperm to remain viable during the time before and after it is frozen, the semen is mixed with a solution containing glycerol or other cryoprotectants. An extender is a solution that allows the semen from a donor to impregnate more females by making insemination possible with fewer sperm. Antibiotics, such as streptomycin, are sometimes added to the sperm to control some bacterial venereal diseases. Before the actual insemination, estrus may be induced through the use of progestogen and another hormone (usually PMSG).

Artificial insemination of farm animals is very common in today's agriculture industry in the developed world, especially for breeding dairy cattle (75% of all inseminations[clarification needed]) and swine (up to 85% of all inseminations). It provides an economical means for a livestock breeder to improve their herds utilizing males having very desirable traits.

Although common with cattle and swine, AI is not as widely practised in the breeding of horses. A small number of equine associations in North America only accept horses that have been conceived by "natural cover" or "natural service" – the actual physical mating of a mare to a stallion. The Jockey Club being the most notable of these - no AI is allowed in Thoroughbred breeding. Other registries such as the AQHA and warmblood registries allow registration of foals created through AI, and the process is widely used allowing the breeding of mares to stallions not resident at the same facility - or even in the same country - through the use of transported frozen or cooled semen.

In 1997, Tilikum, an Orca at SeaWorld Orlando began training for AI. In early 2000, Kasatka who resides at SeaWorld San Diego was artificially inseminated using his sperm. She gave birth to Tillikum's son, Nakai, on September 1, 2001. On May 3, 2002, another female in San Diego, named Takara, bore Tilikum's calf through AI, a female named Kohana. Takara is Kasatka's oldest child and daughter.

ANTIBIOTIC RESISTANCE MECHANISMS

2010-08-13T15:51:00.002+07:00

Antibiotic resistance can be categorized in three types:

1. Natural or intrinsic resistance

Inaccessibility of the target (i.e. impermeability resistance due to the absence of an adequate transporter: aminoglycoside resistance in strict anaerobes)
Multidrug efflux systems: i.e. AcrE in E. coli, MexB in P. aeruginosa
Drug inactivation: i.e. AmpC cephalosporinase in Klebsiella

2. Mutational resistance

Target site modification (i.e. Streptomycin resistance: mutations in rDNA genes (rpsL), ß-lactam resistance: change in PBPs (penicillin binding proteins))
Reduced permeability or uptake
Metabolic by-pass (i.e trimethoprim resistance: overproduction of DHF (dihydrofolate) reductase or thi^-mutants in S. aureus)
Derepression of multidrug efflux systems

3. Extrachromosomal or acquired resistance (Disseminated by plasmids or transposons)

Drug inactivation (i.e. aminoglycoside-modifying enzymes, ß-lactamases, chloramphenicol acetyltransferase)
Efflux system (i.e. tetracycline efflux)
Target site modification (i.e. methylation in the 23S component of the 50S ribosomal subunit: Erm methylases)
Metabolic by-pass (i.e trimethoprim resistance: resistant DHF reductase)

RESISTANCE TO AMINOGLYCOSIDE ANTIBIOTICS

2010-08-13T15:45:00.000+07:00

Aminoglycosides (Streptomycin, kanamycin, tobramycin, amikacin,...) are compounds that are characterized by the presense of an aminocyclitol ring linked to aminosugars in their structure. Their bactericidal activity is attributed to the irreversible binding to the ribosomes although their interaction with other cellular structures and metabolic processes has also been considered. They have a broad antimicrobial spectrum. They are active against aerobic and facultative aerobic Gram-negative bacilli and some Gram-positive bacteria of which staphylococci. Aminoglycosides are not active against anaerobes and rikettsia. Spectinomycin which is an aminocyclitol devoided of aminosugars is by extension included in the familiy of aminoglycosides. It also differs from them by its bacteriostatic ativity and by its way of action. Spectinomycin acts on protein synthesis during the mRNA-ribosome interaction and it does not lead to mistranslation like aminoglycosides do.

Three mechanisms of resistance have been recognized, namely ribosome alteration, decreased permeability, and inactivation of the drugs by aminoglycoside modifying enzymes. The latter mechanism is of most clinical importance since the genes encoding aminoglycoside modifying enzymes can be disseminated by plasmids or transposons.

Ribosome alteration

High level resistance to streptomycin and spectinomycin can result from single step mutations in chromosomal genes encoding ribosomal proteins: rpsL (or strA), rpsD (or ramA or sud2), rpsE (eps or spc or spcA). Mutations in strC (or strB) generate a low-level streptomycin resistance.

Decreased permeability

Absence of or alteration in the aminoglycoside transport system, inadequate membrane potential, modification in the LPS (lipopolysacchaccarides) phenotype can result in a cross resistance to all aminoglycosides.

Inactivation of aminoglycosides

These enzymes are classified into three major classes according to the type modification: AAC (acetyltransferases), ANT (nucleotidyltransferases or adenyltransferases), APH (phosphotransferases).

RESISTANCE TO TETRACYCLINE ANTIBIOTICS

2010-08-13T15:05:00.000+07:00

Tetracyclines (tetracycline, doxycycline, minocycline, oxtetracycline, ...) are antibiotics which inhibit the bacterial growth by stopping protein synthesis. They have been widely used for the past forty years as therapeutic agent in human and veterinary medicine but also as growth promotor in animal husbandry. The emergence of bacterial resistances to these antibiotics has nowadays limited their use. Three different specific mechanisms of tetracycline resistance have been identified so far: tetracycline efflux, ribosome protection and tetracycline modification.

Tetracycline efflux is achieved by an export protein from the major facilitator superfamily (MFS). The export protein was shown to function as an electroneutral antiport system which catalyzes the exchange of tetracycline-divalent-metal-cation complex for a proton. In Gram-negative bacteria the export protein contains 12 TMS (transmembrane fragments) whereas in Gram-positive bacteria it displays 14 TMS. Ribosome protection is mediated by a soluble protein which shares homolgy with the GTPases participating in protein synthesis, namely EF-Tu and EF-G. The third mechanism involves a cytoplasmic protein that chemically modifies tetracycline. This reaction takes only place in the presence of oxygen and NADPH and does not function in the natural host (Bacteroides).

The two first mechanisms are the most widespread and most of their genes are normally acquired via transferable plasmids and/or transposons. These two mechanisms were observed both in aerobic and anaerobic Gram-negative or Gram-positive bacteria demonstrating their wide distribution among the bacterial kingdom. To date, about sixty-one tetracycline resistance genes have been sequenced and thirty-two classes of genes identified in non-producers and producers (Streptomyces). Each new class is identified by its inability to hybridize with any of the known tet genes under stringent conditions (Levy et al. 1989. AAC 33:1373-1374). A new nomenclature for the resistance determinants has been proposed for the future with the S. B. Levy group to coordinate the naming of the detreminants (Levy et al. 1999. AAC 43:1523-1524).

RESISTANCE TO BETA-LACTAM ANTIBIOTICS

2010-08-07T13:58:00.001+07:00

ß-lactams belong to a family of antibiotics which is characterized by a ß-lactam ring. Penicillins, cephalosporins, clavams (or oxapenams), cephamycins and carbapenems are members of this family. The integrity of the ß-lactam ring is necessary for the activity which results in the inactivation of a set of transpeptidases that catalyze the final cross-linking reactions of peptidoglycan synthesis.

In gram positive bacteria, especially staphylococcus aureus, resistance of penicillin G is mainly through the production of beta-lactamase enzymes that break the beta-lactam ring. S.aureus secretes beta-lactamse enzyme extracellularly as inducible exoenzymes that are plasmid-mediated. The inherent resistance to penicillin G of many gram negative bacteria result from low permeability of the gram negative cell wall, lack of PBP`s, and a wide variety of beta-lactamse enzymes. Most gram negative bacteria inherently express low levels of species-specific, chromosomally mediated beta-lactamase enzyme within the periplasmic space, which sometimes contribute to resistance. These enzymes hydrolyze susceptible cephalosphorins more rapidly than penicillin G, but they hydrolyze ampicillin, carbenicillin, and beta-lactamase-resistant penicillins poorly.

Production of plasmid-mediated beta-lactamase is widespread among common gram negative primary and opportunist bacterial pathogens. The enzymes are constitutively expressed, present in the periplasmic space, and cause high-level resistamce. The majority are penicillinases rather than cephalosphorinases. The most widespread are those classified on the basis of their hydrolytic activity as TEM-type beta-lactamases, which readily hydrolyze penicillin G and ampicillin rather than methicillin, cloxacillin, or carbenicillin. The less widespread OXA-type beta-lactamases hydrolyze penicillinase-stable penicillins (oxacillin, cloxacillin, and related drugs). Beta-lactamases probably evolved from PBP`s as a protective mechanism for soil organisms exposed to beta-lactamase in nature, in which they are thought to be widespread through their production by molds. Because of transferable resistance, beta-lactamase production by pathogens is now widespread.

A major advance has been the discovery of broad-spectrum beta-lactamase-inhibitory drugs (e.g. clavulanic acid, sulbactam, tazobactam). These drugs have weak antibacterial activity but show extraordinary synergism when administered with penicillin G, ampicilin, or amoxicillin because of irreversible binding to the beta-lactamase enzymes of resistant bacteria. Other beta-;actamase inhibitors, such as cefotaxime and carbapenems, have potent antibacterial activity in their own right.

VETERINARY STUDENT SCHOLARSHIPS

2010-07-16T10:38:00.000+07:00

Best Vet Scholarships from National Organizations and Colleges

Students aspiring to be veterinarians are truly committed to the profession and to helping animals. But veterinary programs can be unforgiving when it comes to length of time to earn the degree and cost for funding. Thankfully there are many options for scholarships.

National Organizations

We Care Paws-itive Dog Club Scholarship is available to students who are majoring in an animal-related medical field.
The Thoroughbred Scholarship is available to students who wish to pursue a career in veterinary medicine or agricultural science with an emphasis on equine medicine, racetrack management or equine business management. To be eligible, students must be 25 years of age or younger, have at least a C average in high school and must show a financial need. See the pdf.

The Saul T. Wilson Jr. Scholarship Program is for undergraduates and graduates enrolled in college full time and in good academic standing. Undergraduates must have completed at least 2 years of a 4 year pre-veterinary medicine or some other biomedical science program. Graduates must have completed no more than 1 year of study in veterinary medicine. Students must agree to work for the Animal and Plant Health Inspection Service during school breaks. See the pdf.

The American Kennel Club sponsors the Veterinary Student Scholarships to full time students enrolled at a veterinary school in the U.S. Students are selected for scholarships based on academic achievement, financial need and activities with purebred dogs or related.

School Specific

Tufts Cummings School of Veterinary Medicine in Massachusetts offers several scholarship opportunities:
George I. Alden Scholarship Fund provides assistance to deserving students studying veterinary medicine.
Rosamond "Darby" A. Chambers Scholarship Fund proves scholarships to veterinary medicine students.
John F. and Georgia O'Neill Flagg Scholarship Fund for Wildlife Medicine provide assistance to students who are studying veterinary medicine with an emphasis on wildlife medicine.

Scholarship with Restrictions

Veterinary Scholarship Trust of New England awards yearly scholarships to New England (Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, or Vermont) students attending any veterinary school in the U.S. as long as they are in good standing.

U.S. Department of Health and Human Services offers scholarships for full time students who are in financial need and from disadvantaged backgrounds. Students must be enrolled in a degree program for nursing or health professions.

Association of American Veterinary Medical Colleges offers several scholarships:

The Harold Wetterberg Foundation awards scholarships to current or past New Jersey residents who are currently enrolled in post-graduate education in the veterinary medicine field.
The Secretary's Award for Innovations in Health Promotion and Disease Prevention is for students enrolled in a bachelor's degree program in any health science field. This is a writing competition.
The Hill's Public Health Award is for students enrolled in a veterinary program at a college associated with the Federation of Associations of Schools of the Health Professions. This is another writing competition with veterinary medicine as the topic.

CHLAMYDIA TRACHOMATIS

2010-07-09T13:50:00.001+07:00

Chlamydia trachomatis, an obligate intracellular human pathogen, is one of three bacterial species in the genus Chlamydia. C. trachomatis is Gram-indeterminate (i.e. cannot be stained with the Gram stain); structurally the organism is Gram-negative. Identified in 1907, C. trachomatis was the first chlamydial agent discovered in humans.

C. trachomatis includes three human biovars: trachoma (serovars A, B, Ba or C), urethritis (serovars D-K), and lymphogranuloma venereum (LGV, serovars L1, 2 and 3). Many, but not all, C. trachomatis strains have an extrachromosomal plasmid.

Chlamydia species are readily identified and distinguished from other chlamydial species using DNA-based tests.

Most strains of C. trachomatis are recognized by monoclonal antibodies (mAbs) to epitopes in the VS4 region of MOMP. However, these mAbs may also cross-react with two other Chlamydia species, C. suis and C. muridarum.

C. trachomatis is an obligate intracellular pathogen (i.e. the bacterium lives within human cells) and can cause numerous disease states in both men and women. Both sexes can display urethritis, proctitis (rectal disease and bleeding), trachoma, and infertility. The bacterium can cause prostatitis and epididymitis in men. In women, cervicitis, pelvic inflammatory disease (PID), ectopic pregnancy, and acute or chronic pelvic pain are frequent complications. C. trachomatis is also an important neonatal pathogen, where it can lead to infections of the eye (trachoma) and pulmonary complications.

C. trachomatis may be treated with any of several antibiotics: azithromycin, erythromycin or doxycycline/tetracycline.

DOXYCYCLINE

2010-07-09T13:39:00.001+07:00

Doxycycline is a tetracycline antibiotic. It works by slowing the growth of bacteria in the body.

Doxycycline is used to treat many different bacterial infections, such as urinary tract infections, acne, gonorrhea, and chlamydia, periodontitis (gum disease), and others. Doxycycline is also used to treat blemishes, bumps, and acne-like lesions caused by rosacea. It will not treat facial redness caused by rosacea. Doxycycline may be used in combination with other medicines to treat certain amoeba infections.

Do not use doxycycline if you are pregnant. It could cause harm to the unborn baby, including permanent discoloration of the teeth later in life. Doxycycline can make birth control pills less effective. Use a second method of birth control while you are taking doxycycline to keep from getting pregnant. Doxycycline passes into breast milk and may affect bone and tooth development in a nursing baby. Do not take this medication without telling your doctor if you are breast-feeding a baby.

Do not use this medication if you are allergic to doxycycline, or to similar medicines such as demeclocycline (Declomycin), minocycline (Dynacin, Minocin, Solodyn, Vectrin), or tetracycline (Brodspec, Panmycin, Sumycin, Tetracap).

If you have liver or kidney disease, you may need a dose adjustment or special tests to safely take doxycycline.

Do not give doxycycline to a child younger than 8 years old. It can cause permanent yellowing or graying of the teeth, and it can affect a child's growth. Throw away any unused tablets or capsules when they expire or when there are no longer needed. Do not take any doxycycline after the expiration date printed on the bottle. Expired doxycycline can cause a dangerous syndrome resulting in damage to the kidneys.

Do not use doxycycline if you are allergic to doxycycline, or to similar medicines such as demeclocycline (Declomycin), minocycline (Dynacin, Minocin, Solodyn, Vectrin), or tetracycline (Brodspec, Panmycin, Sumycin, Tetracap). Before taking this medicine, tell your doctor if you have liver or kidney disease. You may not be able to take doxycycline, or you may need a dose adjustment or special tests during treatment.

If you are using doxycycline to treat gonorrhea, your doctor may test you to make sure you do not also have syphilis, another sexually transmitted disease.

Do not use doxycycline syrup (Vibramycin) without first talking to your doctor if you have asthma or are allergic to sulfites.

FDA pregnancy category D. This medication can cause harm to an unborn baby, including permanent discoloration of the teeth later in life. Do not use doxycycline without your doctor's consent if you are pregnant. Tell your doctor if you become pregnant during treatment. Doxycycline can make birth control pills less effective. Use a non-hormonal method of birth control (such as a condom, diaphragm, spermicide) to prevent pregnancy while you are taking this medication. Doxycycline passes into breast milk and may affect bone and tooth development in a nursing infant. Do not take this medication without first talking to your doctor if you are breast-feeding a baby. Children younger than 8 years old should not take doxycycline. This medication can cause permanent tooth discoloration and can also affect a child's growth.

ANIMAL WELFARE

2010-07-03T02:24:00.000+07:00

Animal welfare is the physical and psychological state of non-human animals. The term animal welfare can also mean human concern for animal welfare or a position in a debate on animal ethics and animal rights.

Systematic concern for animal welfare can be based on awareness that non-human animals are sentient and that consideration should be given to their well-being, especially when they are used for food, in animal testing, as pets, or in other ways. These concerns can include how animals are killed for food, how they are used for scientific research, how they are kept as pets, and how human activities affect the survival of endangered species.

An ancient object of concern in some civilizations, animal welfare began to take a larger place in western public policy in 19th century Britain. Today it is a significant focus of interest or activity in veterinary science, in ethics, and in animal welfare organizations.

There are two forms of criticism of the concept of animal welfare, coming from diametrically opposite positions. One view, dating back centuries, asserts that animals are not consciously aware and hence are unable to experience poor welfare. The other view is based on the animal rights position that animals should not be regarded as property and any use of animals by humans is unacceptable. Some authorities thus treat animal welfare and animal rights as two opposing positions. Accordingly, some animal right proponents argue that the perception of better animal welfare facilitates continued and increased exploitation of animals. Others see the increasing concern for animal welfare as incremental steps towards animal rights.

Motivations to improve the welfare of animals stems from sympathy and empathy. It can also be based on self-interest. For example, animal producers might improve welfare in order to meet consumer demand for products from high welfare systems. Typically, stronger concern is given to animals that are useful to humans (farm animals, pets etc.) than those that are not (pests, wild animals etc.). The different level of sentience that various species possess, or the perception of such differences, also create a shifting level of concern. Somewhat related to this is size, with larger animals being favored.

There is some evidence to suggest that empathy is an inherited trait. Women have greater concern for animals than men in some societies, possibly the result of it being an evolutionarily beneficial trait in societies where women take care of domesticated animals while men hunt. Interestingly, more women have animal phobias than men. But animal phobias are at least partly genetically determined, and this indicates that attitudes towards animals have a genetic component. Also, children exhibit empathy for animals at a very early age , when external influences cannot be an adequate explanation.

Laws punishing cruelty to animals tend to not just be based on welfare concerns but the belief that such behavior has repercussions toward the treatment of other humans by the animal abusers. Another argument against animal cruelty is based on aesthetics.

External factors that affect people's concern for animal welfare include affluence, education, cultural heritage and religious beliefs. Increased affluence in many regions for the past few decades afforded consumers the disposable income to purchase products from high welfare systems. The adaptation of more economically efficient farming systems in these regions were at the expense of animal welfare and to the financial benefit of consumers, both of which were factors in driving the demand for higher welfare for farm animals.

Interest in animal welfare continues to grow, with increasing attention being paid to it by the media, governmental and non-governmental organizations. The volume of scientific research on animal welfare has also increased significantly.

DESCRIPTION OF IN PAPYRO

2010-07-03T02:11:00.000+07:00

In papyro: referring to experiments or studies carried out only on paper. For example, the term may be applied to epidemiological studies that do not involve clinical subjects, such as meta-analysis. The term is similar to phrases such as in vivo, in vitro, or in silico. Like the latter, in papyro (the correct Latin is in papȳrō) has no actual Latin meaning and was constructed as an analogue to the more popular and longstanding biological sciences terms (vivo and vitro). In papyro is mutually exclusive from in vitro and in vivo, but overlaps with in silico - that is, a study carried out through computer/abstract simulations can also be considered in papyro.

DESCRIPTION OF IN SITU

2010-07-03T02:05:00.000+07:00

In biology, in situ means to examine the phenomenon exactly in place where it occurs (i.e. without moving it to some special medium).

In the case of observations or photographs of living animals, it means that the organism was observed (and photographed) in the wild, exactly as it was found and exactly where it was found. The organism had not been not moved to another (perhaps more convenient) location such as an aquarium.

This phrase in situ when used in laboratory science such as cell science can mean something intermediate between in vivo and in vitro. For example, examining a cell within a whole organ intact and under perfusion may be in situ investigation. This would not be in vivo as the donor is sacrificed before experimentation, but it would not be the same as working with the cell alone (a common scenario for in vitro experiments).

In vitro was among the first attempts to qualitatively and quantitatively analyze natural occurrences in the lab. Eventually, the limitation of in vitro experimentation was that they were not conducted in natural environments. To compensate for this problem, in vivo experimentation allowed testing to occur in the originate organism or environment. To bridge the dichotomy of benefits associated with both methodologies, in situ experimentation allowed the controlled aspects of in vitro to become coalesced with the natural environmental compositions of in vivo experimentation.

In conservation of genetic resources, "in situ conservation" (also "on-site conservation") is the process of protecting an endangered plant or animal species in its natural habitat, as opposed to ex situ conservation (also "off-site conservation").

In oncology: for a carcinoma, in situ means that malignant cells are present as a tumor but has not metastasized, or invaded, beyond the original site where the tumor was discovered. This can happen anywhere in the body, such as the skin, breast tissue, or lung. This type of tumor can often, depending on where it is located, be removed by surgery.

In medicine in-situ means that cancer cells have not passed through the basal lamina. Basically it means the tumor has not invaded lamina propria or the deeper portions of the tissue. Because metastasis generally requires a carcinoma to 'break through' the basement membrane, chances for metastasis is very low.

DESCRIPTION OF EX VIVO

2010-06-19T16:39:00.000+07:00

Ex vivo (Latin: out of the living) means that which takes place outside an organism . In science, ex vivo refers to experimentation or measurements done in or on tissue in an artificial environment outside the organism with the minimum alteration of natural conditions. Ex vivo conditions allow experimentation under more controlled conditions than possible in the intact organism, at the expense of altering the "natural" environment.

A primary advantage of using ex vivo tissues is the ability to perform tests or measurements that would otherwise not be possible or ethical in living subjects. Tissues may be removed in many ways, including in part, as whole organs , or as larger organ systems.

Examples of ex vivo specimen use include:

assays;
measurements of physical , thermal , electrical , mechanical , optical and other tissue properties, especially in various environments that may not be life-sustaining (for example, at extreme pressures or temperatures );
realistic models for surgical procedure development;
investigations into the interaction of different energy types with tissues;
or as phantoms in imaging technique development.

The term ex vivo is often differentiated from the term in vitro in that the tissue or cells need not be in culture; these two terms are not necessarily synonymous.

In cell biology , ex vivo procedures often involve living cells or tissues taken from an organism and cultured in a laboratory apparatus, usually under sterile conditions with no alterations for up to 24 hours. Experiments lasting longer than this using living cells or tissue are typically considered to be in vitro . One widely performed ex vivo study is the chick chorioallantoic membrane (CAM) assay. In this assay, angiogenesis is promoted on the CAM membrane of a chicken embryo outside the organism (chicken).

DESCRIPTION OF IN VITRO

2010-06-19T16:34:00.000+07:00

A procedure performed in vitro ( Latin : within the glass ) is performed not in a living organism but in a controlled environment, such as in a test tube or Petri dish . Many experiments in cellular biology are conducted outside of organisms or cells; because the test conditions may not correspond to the conditions inside of the organism, this may lead to results that do not correspond to the situation that arises in a living organism. Consequently, such experimental results are often annotated with in vitro , in contradistinction with in vivo .

This type of research aims at describing the effects of an experimental variable on a subset of an organism's constituent parts. It tends to focus on organs , tissues , cells , cellular components, proteins , and/or biomolecules . In vitro research is better suited than in vivo research for deducing biological mechanisms of action. With fewer variables and perceptually amplified reactions to subtle causes, results are generally more discernible.

The massive adoption of low-cost in vitro molecular biology techniques has caused a shift away from in vivo research which is more idiosyncratic and expensive in comparison to its molecular counterpart. Currently, in vitro research is vital and highly productive.

However, the controlled conditions present in the in vitro system differ significantly from those in vivo , and may give misleading results. Therefore, in vitro studies are usually followed by in vivo studies. Examples include:

In biochemistry, non-physiological stoichiometric concentration may result in enzymatic active in a reverse direction, for example several enzymes in the Krebs cycle may appear to have incorrect nomenclature.
DNA may adopt other configurations, such as A-DNA .
Protein folding may differ as in a cell there is a high density of other protein and there are systems to aid in the folding, while in vitro, conditions are less clustered and not aided.

It should be pointed out that the term is historical, as currently most lab ware is disposable and made out of polypropylene (sterilizable by autoclaving, ex: microcentrifuge tubes) or clear polystyrene (ex: serological pipettes) rather than glass to ease labwork, ensure sterility, and minimize the possibility of cuts from broken glass.

DESCRIPTION OF IN VIVO

2010-06-19T16:30:00.000+07:00

In vivo ( Latin for "within the living") is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro controlled environment. Animal testing and clinical trials are two forms of in vivo research. In vivo testing is often employed over in vitro because it is better suited for observing the overall effects of an experiment on a living subject. This is often described by the maxim in vivo veritas.

In molecular biology in vivo is often used to refer to experimentation done in live isolated cells rather than in a whole organism, for example, cultured cells derived from biopsies. In this situation, the more specific term is ex vivo . Once cells are disrupted and individual parts are tested or analyzed, this is known as in vitro . in vivo experiment is in living; in vitro study is in test tube.

According to Christopher Lipinski and Andrew Hopkins, "Whether the aim is to discover drugs or to gain knowledge of biological systems, the nature and properties of a chemical tool cannot be considered independently of the system it is to be tested in. Compounds that bind to isolated recombinant proteins are one thing; chemical tools that can perturb cell function another; and pharmacological agents that can be tolerated by a live organism and perturb its systems are yet another. If it were simple to ascertain the properties required to develop a lead discovered in vitro to one that is active in vivo , drug discovery would be as reliable as drug manufacturing."

In the past, the guinea pig was such a commonly used in vivo experimental subject that they became part of idiomatic English: to be a guinea pig. However, they have largely been replaced by their smaller, cheaper, and faster-breeding cousins, rats and mice .

In vivo imaging provides a noninvasive method for imaging biological processes in live animals in order to understand metabolic processes, effects of drugs and disease progression. Near-infrared (NIR) fluorescent detection has proven useful for in vivo imaging in small animals. Low tissue autofluorescence at 800 nm makes it possible to use probes with NIR labels to image tumors and organs. In vivo imaging is an important tool for any research that uses animal models to study diseases, such as Alzheimer's disease.

CANINE DISTEMPER

2010-03-06T17:30:00.000+07:00

Canine distemper is a very serious viral disease that affects animals in the families Canidae,Mustelidae, Mephitidae, Hyaenidae, Ailuridae, Procyonidae, Pinnipedia, some Viverridae and Felidae(though not domestic cats; feline distemper or panleukopenia is a different virus exclusive to cats). It is most commonly associated with domestic animals such as dogs and ferrets, although it can infect wild animals as well. It is a single-stranded RNA virus of the family paramyxovirus, and thus a close relative ofmeasles and rinderpest. Despite extensive vaccination in many regions, it remains a major disease of dogs.

INFECTION

Puppies from three to six months old are particularly susceptible. Canine distemper virus (CDV) spreads through the aerosol droplets and through contact with infected bodily fluids including nasal and ocular secretions, feces, and urine 6–22 days after exposure. It can also be spread by food and water contaminated with these fluids. The time between infection and disease is 14 to 18 days, although there can be a fever from three to six days postinfection.

Canine distemper virus tends to orient its infection towards the lymphoid, epithelial, and nervous tissues. The virus initially replicates in the lymphatic tissue of the respiratory tract. The virus then enters the blood stream and infects the lymphatic tissue followed by respiratory, Gastrointestinal,urogenital epithelium, the Central Nervous System, and optic nerves. Therefore, the typical pathologic features of canine distemper include lymphoid depletion (causing immunosuppression and leading to secondary infections), interstitial pneumonia, encephalitis with demyelination, andhyperkeratosis of foot pads.

The mortality rate of the virus largely depends on the immune status of the infected dogs. Puppies experience the highest mortality rate where complications such as pneumonia and encephalitis are more common. In older dogs that do develop distemper encephalomyetilis, vestibular diseasemay present. Around 15% of canine inflammatory central nervous system diseases are a result of CDV.

DIAGNOSIS

The above symptoms, especially fever, respiratory signs, neurological signs, and thickened footpads found in unvaccinated dogs strongly indicate canine distemper. However, several febrile diseases match many of the symptoms of the disease and only recently has differing between canine hepatitis, herpes virus, parainfluenza and leptospirosis been possible. Thus, finding the virus by various methods in the dog's conjunctival cells gives a definitive diagnosis. In older dogs that develop distemper encephalomyetilis, diagnosis may be more difficult since many of these dogs have an adequate vaccination history.

The most reliable test to confirm distemper is a Brush Border slide/smear of the bladder transitional epithelium of the inside lining from the bladder, stained with Dif-Quick. These cells will always have inclusions. Inclusions in these cells which will stain a carmine red color and be para nuclear in the cytoplasm of infected cells. About 90% of the bladder cells will be positive for inclusions in the early stages of distemper. This is good for at least the first 21 days from onset of the disease. After this point, it gets harder to detect as the disease progresses further in the stages and the physical clinical signs will become quite obvious.

PREVENTION

There exist a number of vaccines against canine distemper for dogs (ATCvet code: QI07AD05 and combinations) and domestic ferrets(QI20DD01), which in many jurisdictions are mandatory for pets. The type of vaccine should be approved for the type of animal being inoculated, or else the animal could actually contract the disease from the vaccine. A dog who has eaten meat infected with Rinderpest can also sometimes receive temporary immunity. Infected animals should be quarantined from other dogs for several months due to the length of time the animal may shed the virus. The virus is destroyed in the environment by routine cleaning with disinfectants, detergents, or drying. It does not survive in the environment for more than a few hours at room temperature (20–25 °C), but can survive for a few weeks in shady environments at temperatures slightly above freezing. It, along with other labile viruses, can also persist longer in serum and tissue debris.

ASPERGILLOSIS

2010-03-06T17:12:00.000+07:00

Aspergillosis is the name given to a wide variety of diseases caused by fungi of the genusAspergillus. The most common forms are allergic bronchopulmonary aspergillosis, pulmonaryaspergilloma and invasive aspergillosis. Most humans inhale Aspergillus spores every day. Aspergillosis develops mainly in individuals who are immunocompromised, either from disease or from immunosuppressive drugs, and is a leading cause of death in acute leukemia andhematopoietic stem cell transplantation. Conversely, it may also develop as an allergic response. The most common cause is Aspergillus fumigatus.

SYMPTOMS

A fungus ball in the lungs may cause no symptoms and may be discovered only with a chest x-ray. Or it may cause repeated coughing up of blood and occasionally severe, even fatal, bleeding. A rapidly invasive Aspergillus infection in the lungs often causes cough, fever, chest pain, and difficulty breathing.

Aspergillosis affecting the deeper tissues makes a person very ill. Symptoms include fever, chills, shock, delirium, and blood clots. The person may develop kidney failure, liver failure (causing jaundice), and breathing difficulties. Death can occur quickly.

Aspergillosis of the ear canal causes itching and occasionally pain. Fluid draining overnight from the ear may leave a stain on the pillow. Aspergillosis of the sinuses causes a feeling of congestion and sometimes pain or discharge.

In addition to the symptoms, an x-ray or computerised tomography (CT) scan of the infected area provides clues for making the diagnosis. Whenever possible, a doctor sends a sample of infected material to a laboratory to confirm identification of the fungus.

DIAGNOSIS

On chest X-ray and computed tomography pulmonary aspergillosis classically manifests as an air crescent sign. In hematologic patients with invasive aspergillosis the galactomannan test can make the diagnosis in a noninvasive way.

TREATMENT

The drugs amphotericin B, caspofungin, flucytosine, itraconazole, voriconazole are used to treat this fungal infection. For severe cases of invasive aspergillosis a combination therapy of voriconazole and caspofungin is suggested as a first line treatment.

EDEMA

2010-03-06T16:45:00.000+07:00

Edema (also spelled oedema, formerly known as dropsy) is swelling due to accumulation of excess fluid in any biological tissue. Edema has many root causes, but the mechanism is simple; fluid is drawn from the blood into the tissues when there is a higher osmotic pressure in the tissues than in the blood. (Blood normally has a higher osmotic pressure than the tissues due to the contribution of the oncotic pressure). This higher pressure may be due to an actual increase (e.g., salt retention due to kidney failure) or it may be a relative increase (e.g., edema due to low serum protein in the blood due to nutritional deficiency). Obstruction to venous blood flow also results in edema due to the mechanically caused increase in blood pressure in upstream capillaries. Capillary damage due to infection, bacterial toxins, or other trauma will also allow fluids to move from the blood into tissues, and the exudation of fluid into extracellular spaces is part of the general process of inflammation.

Common conditions causing or characterized by edema are congestive heart failure, some renal problems, varicose veins, cirrhosis, malnutrition and allergic conditions such as angioneurotic edema.

AMYLOIDOSIS

2010-02-19T17:49:00.000+07:00

Amyloidosis is a group of diseases that result from the abnormal deposition of a particular protein, called amyloid, in various tissues of the body. Amyloid protein can be deposited in a localized area and may not be harmful or only affect a single tissue of the body. This form of amyloidosis is called localized amyloidosis. Amyloidosis that affects tissues throughout the body is referred to as systemic amyloidosis. Systemic amyloidosis can cause serious changes in virtually any organ of the body.

Amyloidosis can occur as its own entity or "secondarily" as a result of another illness, including multiple myeloma, chronic infections (such as tuberculosis or osteomyelitis), or chronic inflammatory diseases (such as rheumatoid arthritis and ankylosing spondylitis). Amyloidosis can also be localized to a specific body area from aging. This localized form of amyloidosis does not have systemic implications for the rest of the body. The protein that deposits in the brain of patients with Alzheimer's disease is a form of amyloid.

Systemic amyloidosis has been classified into three major types that are very different from each other. These are distinguished by a two-letter code that begins with an A (for amyloid). The second letter of the code stands for the protein that accumulates in the tissues in that particular type of amyloidosis. The types of systemic amyloidosis are currently categorized as primary (AL), secondary (AA), and hereditary (ATTR).

In addition, other forms of amyloidosis include beta-2 microglobulin amyloidosis and localized amyloidoses.

BLOOD PLASMA

2010-02-19T17:33:00.000+07:00

Blood plasma is the yellow liquid component of blood, in which the blood cells in whole blood would normally be suspended. It makes up about 55% of the total blood volume. It is the intravascular fluid part of extracellular fluid. It is mostly water (90% by volume) and contains dissolved proteins, glucose, clotting factors, mineral ions, hormones and carbon dioxide (plasma being the main medium for excretory product transportation). Blood plasma is prepared by spinning a tube of fresh blood containing an anti-coagulant in a centrifuge until the blood cells fall to the bottom of the tube. The blood plasma is then poured or drawn off. Blood plasma has a density of approximately 1025 kg/m3, or 1.025 kg/l.

Blood serum is blood plasma without fibrinogen or the other clotting factors (i.e., whole blood minus both the cells and the clotting factors).

Plasmapheresis is a medical therapy that involves blood plasma extraction, treatment, and reintegration.

FRESH FROZEN PLASMA AND OTHER TRANSFUSED PLASMAS

"Fresh frozen plasma" (FFP) is prepared from a single unit of blood or by apheresis, drawn from a single person. It is frozen to −40 °C (−40.0 °F) after collection and can be stored for ten years from date of collection. The term "FFP" is sometimes used informally to mean any frozen transfusable plasma product, including products which do not meet the standards for FFP. FFP contains all of the coagulation factors and proteins present in the original unit of blood. It is used to treat coagulopathies from warfarin overdose, liver disease, or dilutional coagulopathy. Other transfusable plasma is identical except that the coagulation factors are no longer considered completely viable. This is particularly important for Factor VIII and hemophilia, but these have been mostly replaced by more specific Factor VIII concentrates in the developed world and true FFP is rarely used for that indication.

Plasma used as a source of Cryoprecipitate (Plasma, Cryoprecipitate Reduced) cannot be used for treatment of some coagulation problems but is still acceptable for many uses.

DRIED PLASMA

"Dried plasma" was developed and first used in WWII. Prior to the United States' involvement in the war, liquid plasma and whole blood were used. The "Blood for Britain" program during the early 1940s was quite successful (and popular in the United States) based on Dr. Charles Drew's contribution. A large project was begun in August of the year 1940 to collect blood in New York City hospitals for the export of plasma toBritain. Dr. Drew was appointed medical supervisor of the "Plasma for Britain" project. His notable contribution at this time was to transform the test tube methods of many blood researchers, including himself, into the first successful mass productiontechniques.

Nonetheless, the decision was made to develop a dried plasma package for the armed forces as it would reduce breakage and make the transportation, packaging, and storage much simpler.

The resulting Army-Navy dried plasma package came in two tin cans containing 400 ccbottles. One bottle contained enough distilled water to completely reconstitute the dried plasma contained within the other bottle. In about three minutes, the plasma would be ready to use and could stay fresh for around four hours.

Following the "Plasma for Britain" invention, Dr. Drew was named director of the Red Cross blood bank and assistant director of the National Research Council, in charge of blood collection for the United States Army and Navy. Dr. Drew argued against the armed forces directive that blood/plasma was to be separated by the race of the donor. Dr. Drew argued that there was no racial difference in human blood and that the policywould lead to needless deaths as soldiers and sailors were required to wait for "same race" blood.

By the end of the war the American Red Cross had provided enough blood for over six million plasma packages. Most of the surplus plasma was returned to the United States for civilian use. Serum albumin replaced dried plasma for combat use during theKorean War.

PLASMA SHIFT

Blood plasma volume may be expanded by or drained to extravascular fluid when there are changes in Starling forces across capillary walls. For example, when blood pressure drops in circulatory shock, Starling forces drive fluid into the blood vessels, causing autotransfusion.

Also prolonged still standing causes an increase in transcapillary hydrostatic pressure. As a result, approximately 12% of blood plasma volume crosses into the extravascular compartment. This causes and increase in hematocrit, serum total protein, blood viscosity and, as a result of increased concentration of coagulation factors, it causes orthostatic hypercoagulability.

CHRONIC NASAL DISCHARGE IN THE CAT

2010-02-13T03:27:00.000+07:00

Chronic upper respiratory tract (URT) disease is a relatively common problem in cats, and can have many causes. The most common form is termed chronic post viral or idiopathic rhinitis. In this condition viral infection (e.g. cat ‘flu - caused by feline herpesvirus or feline calicivirus) causes the initial mucosal damage; but the chronic signs relate to secondary bacterial infection of the damaged nasal passages. This may then lead on to chronic osteomyelitis of the turbinate bones (bacterial infection of the fine bones within the nose). More unusual causes include:

• Fungal infections which are very uncommon in the UK .

• Inflammation which can result in polyps of inflammatory tissue.

• Neoplasia (cancer) which can be localised within the nose, or be part of more widespread disease.

• Physical damage which can result from foreign objects getting stuck up the nose, facial trauma (e.g. from cat bites or car accidents), or be associated with severe dental disease.

WHAT ARE THE CLINICAL SIGNS OF CHRONIC URT DISEASE ?

The main signs are nasal discharge and difficulty in breathing, ie chronic “snuffles”. The exact nature of the discharge, whether both sides of the nose are affected, and the presence of other clinical signs are dependent on the exact nature of the disease process occurring within the nose, and on the presence of any other illness the cat may have.

In order to determine the extent and nature of the disease it is important that the cat be given a thorough physical examination by a veterinary surgeon. Particular points that the vet will look for include:

• The presence of nasal discharge, and whether it is bilateral (affecting both sides of the nose) or unilateral (affecting only one side of the nose). Some diseases tend to show unilateral signs (e.g. foreign bodies or cancer), while others more often cause bilateral signs (e.g. chronic post viral rhinitis). The type of discharge can also be important; whether it is clear, purulent (pus), or blood stained. Although the presence of a discharge can be helpful in making a diagnosis, it can on occasion be misleading.

• Facial swelling may indicate a more serious underlying problem such as cancer or fungal infections arising within the nasal chambers. Although facial pain is seen rarely, resentment of facial examination is common among cats with URT obstruction, especially those with intranasal foreign bodies, or polyps.

• Sneezing, difficulty in breathing, noisy breathing and mouth breathing may all be seen, but their presence is usually of little diagnostic value.

• Examination of the eyes may reveal ocular discharge ‘runny eyes', usually resulting from tear duct damage associated with previous URT viral disease, but occasionally associated with cancer within the nose. Another legacy of URT viral infection can be the development of chronic inflammation of the cornea (the clear front part of the eye).

• Evidence of painful or infected ears may be associated with inflammatory polyps. Cats with polyps may have problems eating if the polyps are large enough to cause obstruction at the back of the throat.

• Cat's with URT obstruction often have a poor appetite and so experience a degree of weight loss. Marked weight loss is more suggestive of cancer, fungal disease or severe systemic disease.

• The size and shape of the kidneys may be altered if certain cancers are present.

• Mild to moderate enlargement of the lymph nodes (glands) at the angle of the jaw is common, resulting from a local inflammatory response. If the lymph nodes become very large, or if lymph nodes elsewhere in the body are also affected, cancer or fungal infections are most likely to be the cause.

Over-interpretation of clinical signs can be very misleading since different diseases can give rise to similar signs. However, a few general rules do apply, e.g. facial deformity (changes in face shape) with associated pain, especially if accompanied by a unilateral nose bleed or marked lymph node swelling is suggestive of more serious underlying problems such as nasal cancer or fungal disease. Lack of these clinical signs does not rule out these diagnoses as some cases of nasal lymphosarcoma (a common type of cancer) can cause bilateral nasal obstruction and little nasal discharge of any kind. Although post viral rhinitis usually presents as chronic bilateral purulent discharge, it can also result in unilateral discharge, sometimes blood tinged and occasionally with severe nose bleeds.

HISTORY IS IMPORTANT TO HELP WITH DIAGNOSIS

It is very important to know the answers to a number of questions relating to the cat's previous experiences, e.g.

• Did the cat have an acute URT infection (cat ‘flu) as a kitten? This is the most common initiating cause of chronic rhinitis.

• Is there any history of facial trauma, dental disease or ear infections?

• At what age did the cat first develop the clinical signs? The age of onset and speed of onset of clinical signs can often be misleading, but can occasionally be of help in the diagnosis.

• Has the nasal discharge always been of the same type, consistency and colour, and has it always been unilateral or bilateral? Are the signs progressing, is the cat systemically ill, and has the cat responded to any previous treatments? The answers to these questions may help determine the underlying cause of the problems.

My cat had ‘flu as a kitten and has had 'snuffles' ever since, although he is well in himself. Should I ask the vet to find out what is wrong with him?

Arrange for your vet to examine your cat but if chronic post viral rhinitis is believed to be the most likely cause of the patient's clinical signs, and the cat is not too distressed by the nasal discharge, it is probably best not to put it through further examinations (except perhaps an FeLV test). Further investigations are generally best left for cats with severe or progressive clinical signs, or those with evidence of generalised disease.

When considering treating cats with severe chronic URT disease it is helpful, where possible, to differentiate between the possible underlying causes. This allows the correct treatment to be given and the probable outcome to be discussed. However, since most cases of URT disease will result from chronic post viral damage, it is important to remember that tests may give negative results and the likelihood for full recovery, even with treatment, may be poor.

TESTS TO FIND THE CAUSE

• Non-invasive tests, such as haematology, biochemistry and tests for FeLV and FIV may help to determine the extent of systemic disease.

• Nose and throat swabs may be taken to look for the presence of bacteria, viruses or fungi.

• For the best hope of finding a diagnosis it is necessary to give the cat a general anaesthetic in order to perform more extensive investigations. These include taking radiographs (X-rays) and examining the nose and mouth. Detailed examination includes looking up the cat's nose, and examining behind its soft palate (the flap of skin at the back of the throat). While examining the nose it is possible to take samples to look for bacteria, fungi, evidence of inflammation or cancer cells. These methods do not allow very good access to the nasal chambers, so it is possible that underlying disease may sometimes be missed.

• If the less invasive methods of investigation are not successful in gaining a diagnosis it may be necessary to perform an exploratory rhinotomy under general anaesthesia. This involves surgically opening the nasal chambers via the front of the cat's face. This allows for the close inspection of the nasal chambers, the collection of material for biopsy, and the removal of diseased tissue. The procedure is not to be undertaken lightly since although it can be beneficial in some cases, for example where a foreign body, fungal infection or cancer is present, the procedure is traumatic for the cat, and should be reserved for patients with severe clinical signs or those which are already suspected of having nasal cancer or fungal disease. Surgical intervention is rarely curative in cases of chronic post viral rhinitis.

CAN CHRONIC URT DISEASE BE TREATED ?

Yes, but in most cases treatment is unlikely to give a long term cure. In most cases the clinical signs can merely be controlled, since the chronically damaged bones cannot be repaired.

Antibiotics can be given to reduce secondary bacterial infection. It is usually necessary to give them for a long period or as repeated courses in order to control the clinical signs. Since extended courses of antibiotics are generally not advisable for the overall health of the cat, they are usually given only when the cat is severely affected. It is generally hoped that with time the cat, and its owners, will learn to live with the cat's disease, without the need for repeated courses of antibiotics.

Steam inhalation can help. Make a small room, such as the bathroom, steamy or construct a box or tent structure in which a bowl of boiling water can make the atmosphere steamy. Avoid any human proprietary decongestants as many of these are toxic to cats. If the cat is severely affected by ‘snuffles' and is undergoing further investigation, it is possible to therapeutically flush the pus from the nasal passages while the cat is under general anaesthetic. Although this procedure can occasionally give some degree of short term relief, the clinical signs usually return. The most essential aspect of treatment is good nursing care, keeping the cat's face clean and clear of discharge, and encouraging it to eat by feeding warmed up food that is strong smelling. Specific treatments can be given where specific causes have been found, e.g. polyps can be surgically removed, some cancers can be controlled with chemotherapy, and fungal disease can be treated with anti-fungal drugs.

DRUGS THAT DISRUPT MICROTUBULES

2010-02-12T04:53:00.000+07:00

Colchicine, colcemid, and nocadazol inhibit polymerization by binding to tubulin and preventing its addition to the plus ends. The figure to the right shows this inhibition by colchicine (red). Vinblastine and vincristine aggregate tubulin and lead to microtubule depolymerization. Taxol stabilizes microtubules by binding to a polymer.

MICROTUBULE MOTILITY: EXPERIMENTS IN VITRO

2010-02-12T04:52:00.000+07:00

One can label beads with kinesin or dyneins and watch the direction of movement in a cell at the light microscopic level. What would happen if the beads were simply labeled with "cytoplasmic extract"? This cartoon shows the motility process in vitro. The tubule is moving along a negatively charged glass surface and the vesicle moves along the tubule.

This electron micrograph shows microtubules in cross section with the MAP bridge. The arrows point to bridges between microtubules. The star points to a MAP bridge to the vesicle. In summary, MAPs accelerate polymerization, serve as "motors" for vesicles and granules, and essentially control cell compartmentation.

MICROTUBULE ASSOCIATED PROTEINS (MAPS) FUNCTION

2010-02-06T19:00:00.000+07:00

Microtubule associated proteins (MAPs) are tissue and cell type specific. They are high molecular weight proteins (200-300 K) or the tau (20-60 k) proteins. One domain binds to tubulin polymers or unpolymerized tubulin. This speeds up polymerization, facilitates assembly and stabilizes the microtubules. The other end will bind to vesicles or granules. MAPs vary with the cell type. The best examples are found in neurons.

Furthermore, it is believed that some of these MAPs may bind to special sites on the alpha tubulin that form after it is in the microtubule. These are sites where a specific molecule is acetylated or the tyrosine residue is removed from the carboxy terminal. These sites are important marker sites for stabilized microtubules, because they disappear when microtubules are depolymerized.

This figure shows a 3-D view of a neuron with its processes containing microtubules. At higher magnifications, the vesicles are seen attached to MAPs and moving along the microtubule conveyer belt. The MAPs include kinesins and dynein which "walk" along the microtubules in opposite directions.The kinesins move the vesicle along towards the plus end and dynein walks towards the minus end. In neurons, as the microtubules grow from the cell body through the processes, the plus end is more peripheral. These proteins have head regions that bind to microtubules and also bind ATP. The head domains are thus ATPase motors. The tail domain binds to the organelle to be moved. It is not known how the energy from ATP breakdown is converted into vectorial transport.

MICROTUBULE FORMATION

2010-02-06T18:56:00.000+07:00

The first stage of formation is called "nucleation". The process requires tubulin, Mg++ and GTP and also proceeds at 37 C. This stage is relatively slow until the microtubule is initially formed. Then the second phase, called "elongation" proceeds much more rapidly.

During "nucleation", an alpha and a beta tubulin molecule join to form a heterodimer. Then these attach to other dimers to form oligomers which elongate to form protofilaments. Each dimer carries two GTP molecules. However the GTP that appears to function binds to the beta tubulin molecules. When a tubulin molecule adds to the microtubule, the GTP is hydrolyzed to GDP. Eventually the oligomers will join to form the ringed microtubule. The hydrolysis of GTP of course is facilitated at a temperature of 37 C and stopped at temperatures of 4 C.

This figure shows that, as the oligomers assemble, they form a series of rings, 25 nm in diameter. In cross section, each ring consists of 13 beads. The rows of beads in longitudinal section are called protofilaments.

In the cell itself, microtubules are formed in an area near the nucleus called the "aster". Microtubules are polar with a plus end (fast growing) and a minus end (slow growing). Usually the minus end is the anchor point. In this figure, the plus end is shown to the left by the numerous tubulin dimers. This is the end that carries the GTP molecules which may be hydrolyzed to GDP. Hydrolysis is not necessary, however (see p 810 in text and discussion below).

Tests have shown that microtubules will form normally with nonhydrolyzable GTP analog molecules attached. However, they will not be able to depolymerize (see below). Thus, the normal role of GTP hydrolysis may be to promote the constant growth of microtubules as they are needed by a cell.

DYNAMIC INSTABILITY

Microtubules may vary in their rate of assembly and disassembly. Tubulin half life is nearly a full day, however, the half life of a given microtubule may be only 10 minutes. Thus, they are in a continued state of flux. This is believed to respond to the needs of the cell and is called "dynamic instability". Furthermore, there are regulatory processes that appear to control this in a cell. Microtubule growth would be promoted in a dividing or moving cell. However, microtubule growth would be more controlled in a stable, polarized cell.

As described in your text, the cell can provide a GTP cap on the growing end of a microtubule to regulate further growth. This happens when the tubulin molecules are added faster than the GTP can be hydrolyzed. Thus, the microtubule becomes stable and does not depolymerize. It may also be encouraged to continue growing. Once the GTP is hydrolyzed, it begins to shrink, however. Another way of capping a microtubule is to put a structure at its end, such as a cell membrane.

MICROTUBULE STRUCTURE

2010-02-05T18:36:00.000+07:00

Microtubules can be seen in a bundle in this negatively stained preparation to the left. Recall that negative staining starts by immobilizing the preparation on plastic on an electron microscopic grid. Then heavy metal stain is deposited around the structures, delineating their structure. This preparation may allow you to see the tubulin molecules in the protofilaments.

This transmission electron micrograph to the right shows the microtubules in longitudinal ultrathin section. Note, the tubulin molecules cannot be visualized in this preparation.

Early electron microscopists found that in order to preserve microtubules, they had to fix the cells in glutaraldehyde at room temperature. Why do you think the temperature conditions were important? What might happen if they fixed the cells for 30 min in the cold?

Sometimes, you can see collections of microtubules at the periphery of cells. They may be involved in both motility and cytoskeletal functions in this region. It is difficult to see the structure of separate microtubules. Also, microfilaments may also be accumulating in this region.

The extensive distribution of microtubules can really be appreciated in the light microscope after immunolabeling for tubulin with fluorescein-labeled antibodies. This micrograph shows cells in culture labeled for tubulin. The labeling is so fine, the small microtubules can be delineated.

ENCEPHALITIS

2010-02-04T20:02:00.001+07:00

Encephalitis is an acute inflammation of the brain.

Encephalitis with meningitis is known as meningoencephalitis.

Causes

Viral

Viral encephalitis can be due either to the direct effects of an acute infection, or as one of the sequelae of a latent infection. A common cause of encephalitis in humans is herpes (HSE).

Bacterial and other

It can be caused by a bacterial infection such as bacterial meningitis spreading directly to the brain (primary encephalitis), or may be a complication of a current infectious disease syphilis (secondary encephalitis). Certain parasitic or protozoal infestations, such astoxoplasmosis, malaria, or primary amoebic meningoencephalitis, can also cause encephalitis in people with compromised immune systems.Lyme disease and/or Bartonella henselae may also cause encephalitis.

Another cause is granulomatous amoebic encephalitis.

Symptoms

Patients with encephalitis suffer from fever, headache and photophobia with weakness and seizures also common. Less commonly, stiffness of the neck (nuchal rigidity) can occur with rare cases of patients also suffering from stiffness of the limbs, slowness in movement and clumsiness depending on which specific part of the brain is involved. The symptoms of encephalitis are caused by the brain's defense mechanisms activating to get rid of the infection. Other symptoms can include drowsiness and coughing.

Diagnosis

Adult patients with encephalitis present with acute onset of fever, headache, confusion, and sometimes seizures. Younger children or infants may present irritability, poor appetite and fever.

Neurological examinations usually reveal a drowsy or confused patient. Stiff neck, due to the irritation of the meninges covering the brain, indicates that the patient has either meningitis or meningoncephalitis. Examination of the cerebrospinal fluid obtained by a lumbar punctureprocedure usually reveals increased amounts of protein and white blood cells with normal glucose, though in a significant percentage of patients, the cerebrospinal fluid may be normal. CT scan often is not helpful, as cerebral abscess is uncommon. Cerebral abscess is more common in patients with meningitis than encephalitis. Bleeding is also uncommon except in patients with herpes simplex type 1 encephalitis.Magnetic resonance imaging offers better resolution. In patients with herpes simplex encephalitis, electroencephalograph may show sharp waves in one or both of the temporal lobes. Lumbar puncture procedure is performed only after the possibility of prominent brain swelling is excluded by a CT scan examination. Diagnosis is often made with detection of antibodies in the cerebrospinal fluid against a specific viral agent (such as herpes simplex virus) or by polymerase chain reaction that amplifies the RNA or DNA of the virus responsible (such as varicella zoster virus).

Treatment

Treatment is usually symptomatic. Reliably tested specific antiviral agents are available only for a few viral agents (e.g. acyclovir for herpes simplex virus) and are used with limited success for most infection except herpes simplex encephalitis. In patients who are very sick, supportive treatment, such as mechanical ventilation, is equally important. Corticosteroids (e.g. methylprednisolone) are used to reduce brain swelling and inflammation. Sedatives may be needed for irritability or restlessness. Anticonvulsants are used to prevent and treat seizures.

Encephalitis lethargica

Encephalitis lethargica is an atypical form of encephalitis which caused an epidemic from 1917 to 1928, resulting in millions of deaths worldwide. Those who survived sank into a semi-conscious state that lasted for decades until the Parkinsons drug L-DOPA was used to revive those still alive in the late 1960s by Oliver Sacks.

There have been only a small number of isolated cases in the years since, though in recent years a few patients have shown very similar symptoms. The cause is now thought to be either a bacterial agent or an autoimmune response following infection.

Limbic system encephalitis

In a large number of cases, called limbic encephalitis, the pathogens responsible for encephalitis attack primarily the limbic system (a collection of structures at the base of the brain responsible for emotions and many other basic functions).

RABIES

2010-02-04T19:46:00.002+07:00

Rabies is a disease that causes acute encephalitis (inflammation of the brain) in warm-blooded animals. It is zoonotic (i.e., transmitted by animals), most commonly by a bite from an infected animal but occasionally by other forms of contact. Rabies is almost invariably fatal if post-exposure prophylaxis is not administered prior to the onset of severe symptoms.

The rabies virus travels to the brain by following the peripheral nerves. The incubation period of the disease is usually a few months in humans, depending on the distance the virus must travel to reach the central nervous system. Once the rabies virus reaches the central nervous system and symptoms begin to show, the infection is effectively untreatable and usually fatal within days.

Early-stage symptoms of rabies are malaise, headache and fever, progressing to acute pain, violent movements, uncontrolled excitement, depression, and hydrophobia. Finally, the patient may experience periods of mania and lethargy, eventually leading to coma. The primary cause of death is usually respiratory insufficiency. Worldwide, the vast majority of human rabies cases (approximately 97%) come from dog bites. In the United States, however, animal control and vaccination programs have effectively eliminated domestic dogs as reservoirs of rabies. In several countries, including the United Kingdom, Australia and Japan, the virus has been eradicated entirely.

The economic impact is also significant, as rabies is a significant cause of death of livestock in some countries.

STRATIFIED SQUAMOUS NON-KERATINIZED EPITHELIUM

2009-12-27T06:59:00.001+07:00

STRATIFIED SQUAMOUS NON-KERATINIZED EPITHELIUM (40X)

The bar in the image shows you the thickness of the stratified squamous epithelium. The layers underneath it are composed mainly of connective tissue and muscle. At this magnification you can't see any of the individual cells, but you can look for a pattern in the nuclei of the cells in the epithelium. They are sort of difficult to see because the resolution of this image is not very good. Look for dark purple dots in the epithelial layer (the light purple dots are not nuclei--they are due to the low resolution). Notice that the nuclei are arranged in more than one layer. If you can't see the pattern on this image, don't worry. It would be more obvious under the microscope, and will be very easy to see on the next image.

STRATIFIED SQUAMOUS NON-KERATINIZED EPITHELIUM (100X)

Once again the bar shows you the thickness of the stratified squamous epithelium (sse). Just underneath it you can see a layer of connective tissue (ct). Look at the nuclei of the epithelial cells and notice that there are several layers of them. This is your clue that you are looking at a stratified tissue.

STRATIFIED SQUAMOUS NON-KERATINIZED EPITHELIUM (400X), SURFACE

This image shows only the outermost layers of the stratified squamous epithelium. The cells in this tissue are not all squamous (flat). It is named for the shape of the cells on the surface of the tissue. The arrow indicates one of these squamous cells. Notice that two of the cells seem to be separating from the surface of the tissue. This is called sloughing (pronounced "sluffing") and is a normal process in epithelial tissues that form coverings and linings, especially the stratified tissues.

STRATIFIED SQUAMOUS NON-KERATINIZED EPITHELIUM (400X), BASE

This image shows only the lower layers of the stratified squamous epithelium. The dotted line indicates the division between epithelium (above) and connective tissue (below).

The bottom layer is the source of new cells to replace the ones that are sloughing off of the surface. The cells in this layer are usually cuboidal or columnar in shape. As the cells are pushed up towards the surface, their shape changes. You can see that the cells are more flat in the upper part of the image. By the time they reach the surface, they will be squamous.

STRATIFIED SQUAMOUS KERATINIZED EPITHELIUM

2009-12-27T06:52:00.001+07:00

STRATIFIED SQUAMOUS KERATINIZED EPITHELIUM 40X
(PALMAR SKIN)

Although stratified squamous keratinized epithelium covers the entire surface of the body, most of it also includes hair, which makes the basic tissue structure harder to see. If we just want to look at stratified squamous keratinized epithelium, we look at skin from one of the few areas of the body that does not have hair. This tissue is from the palm of the hand (palmar skin). The bar shows the thickness of the stratified squamous keratinized epithelium. In this specimen, the epithelium is stained very dark. The lighter areas underneath are connective tissue (ct).

STRATIFIED SQUAMOUS KERATINIZED EPITHELIUM 100X

(PALMAR SKIN)

At 100X you can see the distinct cell layers that make this a stratified epithelium. The bar indicates the thickness of the stratified squamous keratinized epithelium (sske). Notice that the nuclei of the cells in the bottom layers tend to have a round shape, but that the nuclei seem to become flatter as you move towards the surface. You have probably noticed that the bottom surface of the epithelium is not flat. The bumpy appearance is caused by connective tissue projections called dermal papillae. On all of the images on this page, the epithelium is stained more darkly than the connective tissue.

STRATIFIED SQUAMOUS KERATINIZED EPITHELIUM 400X

(PALMAR SKIN)

The cells on the surface of stratified squamous keratinized epithelium are very flat. Not only are they flat, but they are no longer alive. They have no nucleus or organelles. They are filled with a protein called keratin, which is what makes our skin waterproof. The arrow at the top of the image is pointing to a keratinized cell that has partially separated from the rest of the skin. These dead cells are continually lost from the surface of the skin, and are replaced by new cells from the layers below. The cells on the basal (bottom) layer are actually cuboidal or columnar in shape. They divide by mitosis to produce a constant supply of new cells that replace the ones that are lost from the surface. As these replacement cells are gradually pushed towards the surface, their shape changes. They start out on the bottom as cuboidal cells, then they become irregular in shape, and finally become very flat as they are transformed in the dead, keratin-filled surface cells.

TRANSITIONAL EPITHELIUM

2009-12-27T06:40:00.001+07:00

TRANSITIONAL EPITHELIUM 40X
HUMAN URINARY BLADDER

This image shows part of the wall of the urinary bladder. The bar shows the location and thickness of the transitional epithelium that lines the urinary bladder. The layer of tissue just underneath the epithelium is connective tissue, and at the bottom of the image you can see some smooth muscle tissue.

TRANSITIONAL EPITHELIUM 100X

HUMAN URINARY BLADDER

The bar indicates the thickness of the transitional epithelium

TRANSITIONAL EPITHELIUM 400X

HUMAN URINARY BLADDER

Transitional epithelium is a stratified tissue in which the cells are all have a fairly round shape when the organ it lines is not distended (stretched out). The image shows the wall of the urinary bladder in the relaxed state (not distended). When the tissue is stretched, the cells, especially those on the surface, become flat. This allows organs lined with transitional epithelium to change shape without damaging the epithelial lining. The arrows in the lower left corner of the image point to typical unstretched transitional epithelial cells.

PSEUDOSTRATIFIED CILIATED EPITHELIUM

2009-12-27T06:36:00.001+07:00

PSEUDOSTRATIFIED CILIATED EPITHELIUM (40X)
HUMAN RESPIRATORY TRACT

The bar in this image shows the thickness of the layer of ciliated pseudostratified epithelium. The rest of the tissue below the epithelium is mostly connective tissue, but there are some mucous glands (glandular epithelium) just below the surface. At this magnification you should practice locating the epithelial layer, which is lining part of the respiratory tract. Epithelial tissues that form coverings or linings always have one free (unattached) surface.

PSEUDOSTRATIFIED CILIATED EPITHELIUM (100X)

HUMAN RESPIRATORY TRACT

At 100X you can begin to seee the individual cells that make up pseudostratified epithelium. Notice that most of the cell nuclei tend to be along the bottom (basal) edge of the tissue.

PSEUDOSTRATIFIED CILIATED EPITHELIUM (400X)

HUMAN RESPIRATORY TRACT

Now you can see the individual cells. Once again, the bar shows you the thickness of the ciliated pseudostratified epithelium. The cells in this tissue are very tall and thin, and are not all the same shape. All of the cells are in contact with the basement membrane (on the basal surface), but not all of them reach the surface. The cells that do reach the surface are either ciliated or goblet cells (mucus-secreting cells). The cells that do not reach the surface are probably stem cells and will eventually replace the ciliated and goblet cells. The small bar shows the location and height of the cilia.

SIMPLE COLUMNAR EPITHELIUM

2009-12-27T06:24:00.001+07:00

SIMPLE COLUMNAR EPITHELIUM (40X)
PRIMATE SMALL INTESTINE

You are looking at part of the small intestine. The inner surface of the intestinal wall is made of simple columnar epithelium (sce). Instead of being smooth, the inside of the intestine is folded and covered by millions of tiny projections called villi. On the image, you can see one fold on the right and parts of several villi sticking up from the surface of the fold.

SIMPLE COLUMNAR EPITHELIUM (100X)

PRIMATE SMALL INTESTINE

At 100X you can begin to see the layer of simple columnar epithelium. the best place to look for it is on the surface of the villi. You can see what look like round white bubbles in the epithelium. These are goblet cells and they secrete mucus. The area inside the box is the portion of this image that you will see at 400X. After you have looked at the 400X images and identified the layer of epithelium and the goblet cells, go back and look at the same things again on this image. sometimes it is easier to find something after you have seen it at a higher magnification.

SIMPLE COLUMNAR EPITHELIUM (400X)

PRIMATE SMALL INTESTINE

The arrows are pointing to goblet cells that produce and release mucus. They look clear because the molecules in the mucus do not absorb a lot of stain. The entire layer of simple columnar epithelium is indicated by the bar.

SIMPLE CUBOIDAL EPITHELIUM

2009-12-27T06:19:00.001+07:00

SIMPLE CUBOIDAL EPITHELIUM (40X)
KIDNEY CORTEX

This is the same image we used to show you how to find simple squamous epithelium in the kidney (the outer part of the kidney is at the top). Since each organ in the body is made of two or more tissues, most of the slides you see in lab will have several tissues on them. So you have to learn 1) where to find the tissue you want and 2) how to tell it apart from all of the other tissues that are one the same slide.

This time you are looking for simple cuboidal epithelium. It is found throughout the kidney. It forms most of the microscopic tubes that process body fluids and make urine. You can find it near the glomeruli (round structures in top third of image) and also in the lower parts of the kidney (The bar will be explained later.)

SIMPLE CUBOIDAL EPITHELIUM (100X)

KIDNEY CORTEX

Cuboidal cells are about as tall as they are wide. The nucleus is usually round and located in the center of the cell. Simple epithelial tissues have only one layer of cells.

Knowing about the shape and position of the nucleus in the cells will allow you to recognize tissues even when you can't tell where the edges of the cells are. Since you are trying to find a simple cuboidal epithelium, look for rows or rings of round dark dots (the nuclei of the cuboidal epithelial cells). Most of the cells in this image are simple cuboidal epithelial cells.

SIMPLE CUBOIDAL EPITHELIUM (400X)

KIDNEY CORTEX

The arrow is pointing to a cross section of a tube made of simple cuboidal epithelium. Start at the point of the arrow and follow the nuclei in a circle until you get back to the arrow. There are several other tubes shown in cross section on this image.

Some of the tubes were sliced (sectioned) straight across and they look like circles. In other places the tubes were cut at an angle (in anatomy this is called an oblique section) and they look more like ovals. In the inner parts of the kidney (on the middle third of the top image on this page) the tubes are sliced longitudinally (long wise) and the cells that make up the walls of the tubes appear in parallel rows.

SIMPLE CUBOIDAL EPITHELIUM (100X)--THICK SECTION

KIDNEY MEDULLA

This image is from the part of the kidney indicated by a bar in the top image on this page. You are now looking at the same structures but from a different angle. All of the structures in this image are sections of kidney tubules.

SIMPLE CUBOIDAL EPITHELIUM (400X)--THICK SECTION

KIDNEY MEDULLA

This image is an enlargement of the one just above it. The color of the stain is different from the top three images, but you can still recognize the pattern formed by the nuclei of the simple cuboidal epithelial cells--just look for the circles. The individual cells can be seen in this image, making the simple cuboidal epithelium even easier to recognize.

SIMPLE SQUAMOUS EPITHELIUM KIDNEY CORTEX

2009-12-27T05:55:00.004+07:00

SIMPLE SQUAMOUS EPITHELIUM, C.S. (40X)
KIDNEY CORTEX

This very tall image shows almost the entire thickness of the kidney. Your goal is to find and learn to recognize simple squamous epithelium on a slide similar to this. The easiest place to find this tissue is the glomerular capsule (don't worry, you don't have to know what that is to find and recognize the tissue). In the top one third of the image you can see circular structures surrounded by a thin white space. The arrows point to two of these structures. The white space is the inside of the glomerular capsule, and the simple squamous epithelium forms a thin layer around the outside of the white space.

SIMPLE SQUAMOUS EPITHELIUM, C.S. (100X)

KIDNEY CORTEX

In this image the arrow is again pointing to a glomerular capsule. (The rectangle shows which part of this image has been enlarged and shown below.) At this magnification you can't see the tissue yet, but you will get a better idea of where to look.

SIMPLE SQUAMOUS EPITHELIUM, C.S. (400X)

KIDNEY CORTEX

This image is the area that was enclosed in a rectangle in the previous image. The dark purple spots are the nuclei of cells, and the cytoplasm is stained a dark pink color. The glomerular capsule is marked with an asterisk (*). Look around the outer edge of the capsule and you will see some short, thin, dark lines. These are the nuclei of the simple squamous epithelial cells. There is a simple squamous epithelial cell nucleus just to the right of the asterisk.

SIMPLE SQUAMOUS EPITHELIUM, C.S. (400X) THIN SECTION

KIDNEY CORTEX

The arrows in the image point to the nuclei of simple squamous epithelial cells. This image was made from a thin section of the kidney at the same magnification as the previous image (400X). It is about one-fifth to one-tenth the thickness of the slides used to make the top three images on this page.

Thin sections allow us to see more detail, but they are usually lighter because there is not as much tissue to absorb stain. Another difference between this slide and the previous three is that the glomerular capsule is much harder to see here. In thick sections tissues shrink more during processing, which leaves bigger spaces between the cells. The space in the glomerular capsules that you see in the top three images is not present in living tissue. This thin-section image is more life-like because it didn't shrink as much and there aren't such large spaces between cells. But the one advantage of the shrinkage in the thick sections is that it gives you an easy landmark for finding the simple squamous epithelial tissue. You will usually be using thick section slides in lab.

E.COLI K99 ON THE ZONA PELLUCIDA ( PENAUT E.COLI KE ZONA PELUSIDA )

2009-12-06T21:00:00.002+07:00

SUMMARY
Isolation and identification of active substance wich attachEscherichia coli K99 bacteria on the surface of the zona pellucida embryo is important to be conducted to prevent embryos contamination. For that popuses a laboratory study on the attachment of E. coli K99 on the zona pellucida of mouse embryos was carried out by enzyme-linked immunosorbent assay (ELISA) and scanning electron microscopy (SEM). The zona pelucida of mouse embryo was separated from embryo by embryo hatching and sonification. The separated zona pellucida was then used antigen for ELISA. Suspension of several different Escherichia coli isolates with or without K99 antigen was prepared in PBS. K99 villous antigen was prepared by heating of the bacterial suspension at 60oC for I hour, and followed by centrifugation. Embryos with an intact zana pelucida were inoculated with E. coli at the dose of 105cells per ml and incubated for 1 hour at 37oC. After 3 times washes with PBS, the embryos were examined by scanning electron microscope. The result showed that the ELISA readings (optical density) of samples with K99 antigen was significantly higher than those without K99 antigen (K88 and F41). The attachment of E. Coli to the plate coated with zona pellcida was observed only in the well containing K99 antigen, but not in the well containing K88 or F41 antigen. The attachment of K99 bacterial cells was also observed by SEM. This study provide a clear evidence for the specific attachment between E. coli K99 and the zona pellucida of mouse embryo. As we know, the E.coli K99 specifically attach to mannose, so the active substance on the surface of the zona pellucida was mannose. Key words: ELISA, SEM, zona pellucida, E.coliK99, mannose

RINGKASAN
Isolasi dan identifikasi bahan aktif yang merekatkan bakteri E.coli K99 ke permukaan zona pelusida perlu dilakukan untuk mencegah pencemaran. Untuk itu telah dilakukan penelitian laboratoris tentang perlekatan E.coli K99 pada zona pelusida mencit. Sampai kini belum ada informasi mengenai perlekatan antara E.coli K99 dengan zona pelusida yang dilacak menggunakan ELISA dan SEM. Uji ELISA dipersiapkan guna melacak perlekatan ini. Untuk itu, zona pelusida mencit dipisahkan, setelah embrio hatching dan selanjutnya disonikasi. Zona pelusida yang telah disonikasi dipandang sebagai antigen dan digunakan untuk melapisi sumuran cawan ELISA. Suspensi E.coli dalam PBS, baik bakteri yang memiliki K99 mau pun yang tidak, dipersiapkan dari sel-sel bakteri utuh yang berasal dari isolat yang berbeda. Antigen pili K99 dipersiapkan dengan pemanasan suspensi E.coli K99 pada suhu 600C selama satu jam. Pili K99 diperoleh dengan melakukan sentrifyus. Embrio yang memiliki zona pelusida utuh dicemari dengan bakteri E.coli K99 sebanyak 105 per ml, diinkubasikan selama satu jam pada suhu 370C. Selanjutnya embrio yang tercemar itu dicuci dengan mPBS dan dipersiapkan untuk pemeriksaan mikroskop electron. Hasil penelitian ini menunjukkan bahwa kepadatan optik sample-sampel yang mengandung antigen K99, angkanya lebih tinggi dibandingkan dengan yang tidak (K88 dan F41). Dalam penelitian ini ditemukan adanya perlekatan antara antigen K99 dengan zona pelusida pada sumuran yang dilapisi dengan zona pelusida, dan tidak dengan K88 dan F41. Hal ini berarti bahwa terjadi perlekatan antara antigen K99 dengan zona pelusida. Dengan SEM, bakteri E.coli K99 terlacak melekat pada permukaan embrio. Kesimpulan yang dapat ditarik dari penelitian ini bahwa terjadi perlekatan yang spesifik antara E.coli K99 dengan zona pelusida, yang ditunjukkan antara pili K99 dengan ekstrak zona pelusida. Diketahui bakteri E.coli K99 mampu melekat ke manosa. Maka unsur reseptor E.coli K99 pada zona pelusida adalah gula manosa. Kata-kata kunci : ELISA, SEM, zona pelusida, E.coli K99, manosa

PENYAKIT RESPIRASI HEWAN KECIL

2009-12-06T20:52:00.002+07:00

1. BATUK

Definisi :

Batuk adalah suara yang timbul akibat keluarnya udara pernafasan secara tiba-tiba dari paru-paru

Patofisiologi

Fungsi batuk adalah reflek perlindungan normal tubuh untuk mengeluarkan benda asing dari saluran nafas. Reseptor batuk pada sistem respirasi sebagian besar pada saluran nafas atas, dan tidak ada pada bronchiole. Pathways afferent dari reflek batuk berjalan melewati nervus vagus, trigeminus, glosofaringeus dan perineal. Impul akan dikirim ke pusat batuk di medula oblongata. Kemudian Impul efferent akan disebarkan melalui nervus vagus, prenial dan nervus spinal ke laring, pohon trakeobronchial, diafragma dan otot respirasi. Reseptor batuk juga terdapat di hidung, sinus paranasal, dan faring. Reseptor batuk akan merespon rangsangan kemikal dan mekanik .

Efek menguntungkan dari batuk adalah membersihkan saluran nafas terutama trakea, dan bronchus. Pada batuk persisten dan berat, terutama batuk kering dan nonproduktif akan merugikan hewan itu sendiri, karena kondisi tersebut : mempercepat penyebaran infeksi pada saluran Nafas; Memperparah radang dan iritasi saluran nafas; Memperbesar distensi alveoli yang berpengaruh ke emfisema; Menyebabkan pneumothorak karena ruptur saluran nafas; dan Memperlemah kondisi dan menambah kelelahan pasien.

Penyebab batuk dapat dikelompokkan menjadi tiga tergantung lokasi saluran nafas yaitu Saluran nafas atas (Paringitis, tonsilitis, trakeitis, kolaps trakea); Saluran nafas bawah ( bronchitis akut dan kronis, bronchiectasis, pneumonia, fibrosis dan abses pulmonun, pembesaran limponodus, bronkitis alergi, parasit paru, trauma bronchus, iritasi asap rokok dan pembakaran); dan Sistem kardiovaskular (gagal jantung kiri, pembesaran aterial kiri, parasit jantung, trombosis pulmonum, dan edema pulmonum) .

Rencana diagnostik

Pengamatan fisik dan sejarah

Gejala yang sering mengaburkan pemilik hewan tentang batuk yaitu : gagging, pengeluaran dahak, regurgitasi, dan muntah. Pada beberapa kasus anjing penderita batuk, pemunculan gejala batuk dapat dimanipulasi dengan cara meraba trakea secara perlahan dan lembut. Hal itu dapat dilakukan dihadapan pemilik untuk mengkonfirmasi tentang gejala yang mereka amati.

Pemeriksa harus bertanya ke pemilik anjing tentang keadaan lingkungan tempat anjing dipelihara, seperti jenis kandang, lokasi kandang, lantai kandang, alas tidur, air minum dan atap kandang. Hal lain yang penting juga ditanyakan ke pemilik yaitu : Kontak dengan anjing lain yang sakit, polusi udara (asap rokok, asap pembakaran), dan kemungkinan tertular parasit. Tanyakan ke pemilik tentang gejala lain yang teramati seperti : depresi, lethargi, anoreksia, dispnea, tidak respon dengan latihan. Hal ini akan sangat membantu dalam penyingkiran diagnosis sementara sehingga diagnosis menjadi lebih akurat.

Gejala khas batuk yang sangat membantu dalam penegakan diagnostik yaitu: Batuk keras, kasar dan kering hal itu biasanya gejala dari iritasi atau radang laring, trakea, bronchi. Hal itu sering dijumpai pada anjing yang menderita penyakit trakeobroncitis (kennel cough), dan pada kucing penderita rhinotrakheitis. Batuk “goose honk” sering dijumpai pada anjing toy-breed yang menderita kolaps trakhea.

Auskultasi torak dilakukan secara hati-hati dan pelan-pelan pada penderita batuk. Auskultasi harus dilakukan terhadap jantung dan paru-paru. Auskultasi akan sangat dibantu dengan manipulasi trakea untuk merangsang batuk dan selanjutnya dilakukan reauskultasi torak kembali. Suara abnormal sering terdengar pada awal atau intensif setelah hewan batuk beruntun. Suara lain yang sering terdengar pada penderita batuk adalah suara Crackles, wheezes dan peningkatan suara normal nafas. Suara cardiac murmur, kelainan ritme jantung dapat juga diauskultasi pada hewan penderita batuk karena kelainan jantung.

Tabel 1. Perbedaan dari penyebab batuk secara umum

Penyebab batuk
Saluran Nafas atas	Saluran nafas bawah	Kardiovascular
Depresi/lethargi	Absen atau ringan	Ringan - berat	Sedang – berat
Demam	Absen atau ringan	Ringan	Tidak ada
Dehidrasi	Absen	Ringan	Ringan
Batuk-batuk	Sering	Kadang-kadang	Kadang-kadang
Dispnea	Umumnya absen	Ringan	Ringan
ketahanan latihan	Absen atau ringan	Ringan	Sedang
Suara paru	normal	Abnormal	Abnormal
Suara jantung	normal	Normal	Abnormal
WBC	normal	Meningkat	Normal atau meningkat
Rongsen torak	normal	abnormal	Abnormal

Dikutip dari: MD Lorenz dan LM Cornelis. 1987. Small animal medical diagnosis,

Evaluasi Laboratorium

Pemeriksaan laboratorium harus dilakukan jika pasien menunjukkan gejala sakit seperti demam, depresi, anoreksia, dispnea diikuti oleh batuk atau jika batuk bersifat kronis (lebih dari 1 minggu). Pemeriksaan laboratorium yang dilakukan meliputi: Hitung darah Lengkap, differential, profil biokimia serum, dan analisis urin.

Radiografi

Pemeriksaan radiografi torak dilakukan untuk memperluas pemeriksaan fisik pasien batuk. Anatomi normal torak harus dibandingkan dengan kelainan yang dijumpai pada torak.

Tes elektrofisiologi

Tes ini dilakukan terutama pada pasien gangguan jantung yang ada gejala batuk. Uji ini meliputi uji elektrocardiogram. Uji khusus yaitu echocardiografi perlu juga dilakukan.

Pencucian transtrakheal

Evaluasi dari lapisan mukosa respirasi dari trakea sampai alveoli dapat didapat dari pencucian transtrakeal. Hal ini dilakukan dalam kondisi hewan terbius dan hewan dipasang tube endotrakeal. Pencucian menggunakan larutan saline steril seperti lactat ringer’s atau NaCl 0.9%.

Bronchoscopi

Pengamatan bronchoscopi perlu dilakukan pada pasien batuk, tetapi ini harus dilakukan pada hewan dalam kondisi terbius total dan alat yang diperlukan agak mahal.

Tabel 2. Penyebab Batuk pada Anjing dan Kucing dan Temuan Khas

	Sejarah/pemeriksaan fisik	Pemeriksaan laboratorium	Radiografi
ANJING
Paringitis/laringitis akut	Batuk pendek diikuti gagging dan menelan dahak, suara parau, kemerahan pring dan laring, tidak ada gejala sistemik	normal	Normal
Traketis	Sejarah kontak dengan anjing lain, batuk kering dan pendek, tidak ada gejala sistemik	normal	Normal
Pneumonia aspirasi	Sejarah pembiusan umum dan megaesopagus, batuk basah dan dalam, dispnea, demam	WBC meningkat, neutropilia	Alveolar konsolidasi
Infektius trakeobronkitis kronis	Sejarah kontak dengan anjing lain, batuk kering dalam dan persisten, tidak ada gejala sistemik	normal	Normal
Kolaps trakea	Toy breed kegemukan, batuk goose honk, dispnea, kolap trakea	normal	Kolaps trakea, kolaps bronkial
Alergi bronkitis	Batuk kering, dalam dan produktif; dispnea; crackles, wheeze; tanpa gejala sistemik	Periperal eosinophilia, eosinopilic inflamasi pada transtrakeal wash	Bronkial jelas terlihat
Cacing jantung	Berat badan turun, batuk persisten, dispnea ringan sampai berat, exercise intoleran	Periperal eosinopilia, hiperglobulinemia, positif mikrofilaria,	Pembesaran jantung kanan, pembesaran arteri pulmonum,
Gagal jantung kiri	Anjing ras kecil dan tua; batuk pada malam hari; dispnea; exercise intolerance	ECG variasi; hipertropi ventrikel kiri	Arterial kiri membesar, pembesaran vena pulmonum, edema pulmonum disekitar jantung
KUCING
Viral rhinotraketis akut	Kontak dengan kucing lain; bersin dan kemerahan hidung, mata berair, ulcer mulut	WBC meningkat	Normal
Feline asma kronis	Batuk paroksimal, dalam, produktif dan leher diluruskan; dispnea berat, sianosis	Periperal eosinopilia	Paru hiperinflamasi
Cacing paru	Batuk paroksimal, dalam, produktif dan leher diluruskan; dispnea, demam	Periperal eosinopilia; positif larva pada transtrakeal wash	Brokial membesar
Cacing jantung	Nafsu makan menurun, muntah sporadik, batuk kadang-kadang	Periperal eosinopilia, hiperglobulinemia,	Pembesaran arteri pulmonari; pembesaran ventrikel kanan

Dikutip dari: MD Lorenz dan LM Cornelis. 1987. Small animal medical diagnosis,

Terapi Simtomatis

1. Bronkodilatator

Kandungan obat bronkodilatator memberikan keuntungan dalam pengobatan pasien batuk karena mempunyai efek bronkospasmus. Dua katagori bronkodilatator adalah (a) Inhibitor posfodiester : theopilin dan aminopilin (10 mg/kg, 3-4x/hari untuk anjing; 5 mg/kg, 2-3x untuk kucing). Cara kerja obat ini dengan cara memecah secara perlahan cAMP sehingga otot polos bronkus relaksasi, dan meningkatkan kontraksi diafragma; (b) Simpatomimetik : terbutalin (2.5 mg/kg, 3x/hari untuk anjing; 1.25mg/kg, 2x/hari untuk kucing), metaproterenol, isoproterenol. Cara kerja obat ini sebagai agonis reseptor beta-adrenergik.

2. Supressant batuk

Obat antitussive dikelompokkan menjadi dua katagori yaitu : (a) Kerja central : hidrocodone bitartat ( 2.5-10 mg, 2-3x/hari, po), butorphanol tartate / torbutrol (0.5/kg, 2x/hari, po; 0.05/kg 2x/hari, Sc). Cara kerja obat ini adalah menekan pusat batuk di medula oblongata, dan dengan efek samping hewan tertidur. (b) Kerja perifer, dengan cara meningkatkan nilai ambang reseptor batuk.

3. Ekspectorant

Obat ini meningkatkan volume cairan saluran nafas sehingga merangsang pengeluaran eksudat dari saluran nafas. Keberhasilan obat ini pada pasien batuk masih diragukan.

4. Antihistamin

Walaupun banyak digunakan pada obat batuk yang telah beredar, tetapi secara umum tidak memberikan efek antitusiv yang substansial. Kejelekan obat ini dapat menyebabkan kekeringan pada mukosa. Sedangkan kebaikan obat ini dapat menyebabkan hewan mengantuk.

5. Terapi aerosol

Terapi aerosol dilakukan untuk mencairkan dahak yang mengental terutama yang di bronkhial tree. Partikel aerosol yang diperlukan berukuran antara 1 – 2 mikron. Dalam melakukan nebulisasi, alat nebulizer yang digunakan perlu dimodifikasi supaya dapat menutupi muka dari pasien. Obat yang sering digunakan dalam nebulisasi adalah gentamisin dalam larutan saline 0. 45% atau 0.9%. Nebulisasi juga dapat dilakukan dirumah yaitu di kamar mandi dengan shower panas.

2. DISPNEA

Definisi

Dispnea adalah kondisi kesulitan atau kesusahan dalam bernafas.

Patofisiologi

Dispnea adalah kondisi patologis, tetapi takipnea (meningkatnya rata-rata bernafas) dapat bersifat fisiologis seperti pada kondisi kebanyakan bergerak, udara panas, dan gelisah. Disamping itu dapat juga bersifat patologis. Kesulitan bernafas dapat terjadi karena alasan sebagai berikut : keperluan tambahan oksigen; kompensasi metabolik acidosis; peningkatan suhu lingkungan (heatstroke); kerusakan atau penyakit pusat respirasi di sistem saraf pusat (CNS); kelemahan otot respirasi atau disfungsi nervus motor dari respirasi; dan rasa sakit dari organ yang terlibat dalam bernafas seperti pleura, nervus spinal, otot respirasi, dan tulang rusuk.

Kekurangan pemenuhan oksigen dapat disebabkan oleh kekurangan oksigen di lingkungan, gangguan transfer oksigen dari lingkungan ke dalam darah atau menurunnya kemampuan pengangkutan oksigen oleh darah (anemia, methemoglobinemia). Kompensasi terhadap metabolik asidosis menyebabkan peningkatan frekuensi dan kedalaman nafas.

RENCANA DIAGNOSTIK

Sejarah dan Pengamatan Fisik

Sejarah penyakit yang ditanyakan meliputi pertanyaan mengenai apakah dispnea awalnya terjadi secara tiba-tiba atau terjadi secara perlahan-lahan dan terus bertambah berat. Tanyakan apakah hewan selalu dikandangkan atau dibawah pengawasan seseorang sehingga memungkinkan mendapat trauma. Beberapa breed anjing lebih mudah mendapatkan trauma yang menyebabkan dispnea. Misalnya anjing brachicephalik lebih mudah mendapat trauma pada saluran nafas atas, dan anjing pemburu mudah menderita dispnea karena jamur. Umur anjing juga perlu diperhatikan. Karena tumor lebih sering pada anjing tua.

Pengamatan yang teliti terhadap pola respirasi akan sangat membantu dalam melokalisasi penyebab dispnea. Gangguan saluran nafas bagian atas diikuti dengan dispnea inspirasi yang ditandai dengan gejala khas seperti jarak antar inspirasi, kesusahan dalam inspirasi, waktu inspirasi singkat dan terlihat fase ekspirasi mudah. Penyakit pada saluran nafas bawah menyebabkan dispnea inspirasi dan ekspirasi dengan rata-rata respirasi cepat.

Evaluasi laboratorium

Pemeriksaan laboratorium meliputi hitung darah lengkap, biokimia serum, analisis urin.

Radiografi

Pemeriksaan radiografi meliputi pemeriksaan kepala dan torak

Sitologi

Pemeriksaan ini dilakukan jika teramati terjadi kebocoran pleura saat radiografi. Toracocentesis dilakukan secara aseptis dan cairan yang diperoleh diamati. Kandungan protein diukur dengan refractometri, hitung sel dan differential sel harus dicatat dengan baik, dan juga perlu dilakukan kultur bakteri dan jamur dari cairan itu.

TERAPI SIMTOMATIS

Terapi simtomatis pada penderita dispnea tergantung dari penyebab penyakit. Perlu diingat hewan yang dispnea tidak boleh terlalu stres. Pemberian oksigen dengan corong oksigen, penutup kepala atau tube nasal sangat diperlukan.

Penting diperhatikan apakah anjing itu terserang penyakit yang bersifat restriktif seperti bocor pada pleura, pneumotorak, atau ada massa intratorak. Edema pulmonum harus segera ditangani dan tidak boleh ditunda. Cairan pleura dapat dikeluarkan dengan torakocentesis menggunakan jarum 22G dengan panjang 1 inchi, dengan siring 20 ml. Alternatif dapat digunakan cateter intravenous polietilen. Udara pada pleura juga dapat dikeluarkan dengan cara yang sama.

Hipoalbuminemia sering terjadi akibat pengeluaran cairan pleura dan mempercepat kebocoran pleura. Jika pengeluaran cairan terlalu banyak, konsentrasi albumin serum harus diukur minimal dua kali seminggu. Jika konsentrasi serum albumin berkurang sampai dibawah 2.0 g/dl jumlah cairan pleura yang dikeluarkan harus dikurangi. Penggunaan furosemida dapat membantu mengkontrol pembentukan cairan pleura. Transfusi plasma atau darah sangat diperlukan pada penderita hipoalbuminemia (serum albumin < 1.0 g/dl).

Bronkodilatator sangat membantu jika gangguan terjadi pada saluran nafas bagian bawah, dan gangguan jantung. Penggunaan bronkodilatator golongan teopilin akan meningkatkan kontraksi diafragma, meningkatkan fungsi mucociliari dari mukosa respirasi, dan mengakibatkan diuresis ringan.

Pengobatan sistemik pada penderita dispnea, diberikan furosemida secara intravena atau oral. Efek samping dari furosemida adalah dehidrasi, azotemia, dan hipokalemia, untuk itu, obat digunakan dengan dosis minimal dan dalam jangka waktu singkat (2 – 3 hari).

3. HEMOPTYSIS

Definisi

Hemoptysis adalah batuk diikuti dengan keluarnya darah.

Patofisiologi

Hemoptysis disebabkan oleh satu atau lebih dari kerusakan berikut : kerusakan buluh darah; hipertensi pulmonum hebat; dan masalah pembekuan darah. Kerusakan buluh darah dapat disebabkan oleh peradangan, nekrosis, neoplasia atau trauma. Hipertensi pulmonum umumnya disebabkan oleh tromboembolisme pulmonum, gangguan ventrikuler kiri. Gangguan pembekuan darah diakibatkan oleh abnormalitas faktor pembeku atau platelet.

Hemoptysis menyebabkan kehilangan darah dalam jumlah sedikit tetapi jika berlangsung kronis dapat berkembang jadi anemia, aspiksasi dan hipovolemia.

Rencana Diagnosis

Sejarah dan Pengamatan Fisik

Sebelum melakukan pengobatan terhadap hemoptysis, perlu dilakukan lokalisasi dari sumber perdarahan. Ludah yang bercampur darah disebabkan karena perdarahan pada nasoparing, respirasi atau gastrointestinal.

Pertanyaan yang teliti pada pemilik akan membantu diagnosis. Bersih yang persisten dan parah dengan nasal discharge bercampur darah sebelum hemoptysis sebagai indikasi kerusakan terjadi pada rongga hidung. Sejarah dengan batuk berat dan dispnea sebagai indikasi kerusakan pada saluran nafas.

Pengamatan fisik dilakukan secara menyeluruh pada semua organ yang meliputi rongga mulut, dan nasoparing. Auskultasi torak untuk konfirmasi terjadinya gangguan jantung.

Evaluasi Laboratorium

Evaluasi laboratorium dilakukan jika hemoptysis tidak massive dan mengancam jiwa pasien, dan pemeriksaan dikonfirmasi dengan radiografi. Pemeriksaan laboratorium meliputi hitung darah lengkap, platelet, biokimia serum, urinalisis, uji cacing jantung, pembekuan darah, analisis gas darah, electrocardiogram, transtracheal wash, bronchoscopi, dan sampel aspirasi. Pada hemoptysis yang mengancam jiwa pasien, pemeriksaan laboratorium ditunda sampai kondisi pasien stabil.

Terapi simtomatis

Untuk hemoptysis ringan dan tidak mengancam jiwa pasien pengobatan simtomatis dapat dilakukan dengan pemberian supressant batuk, dan bronchodilatator. Pasien harus dijaga supaya tetap tenang, dibantu dengan pemberian obat penenang.

Pada pasien hemoptysis yang terancam jiwanya, tindakan emergensi harus dilakukan untuk membantu jiwa pasien. Pertama yang perlu diperhatikan yaitu sirkulasi udara tetap lancar, restoring volume darah, tindakan bedah untuk menghentikan perdarahan.

4.SUARA PARU ABNORMAL

Definisi

Suara abnormal paru didengar saat auskultasi di atas torak pada beberapa pasien yang menderita penyakit saluran nafas.

Patofisiologi

Asal secara pasti suara normal nafas tidak dipahami secara baik. Suara paru dipercaya dihasilkan oleh goyangan pada jaringan respirasi yang padat dan oleh kecepatan fluktuasi tekanan gas. Suara paru dihasilkan dari tersaringnya udara atau masuknya udara ke saluran yang lebih kecil dari luar paru menuju dinding torak. Selanjutnya suara normal paru terdengar saat auskultasi torak yang terdiri atas suara individu yang bergabung dari berbagai tempat di paru-paru. Suara normal paru awalnya berasal dari trakea, lobar dan bronki segmental. Suara itu memiliki gambaran yang berbeda dari suara normal paru yang berasal dari alveoli. Aliran pada acinar dan level alveolar adalah berlapis-lapis dengan velositi rendah, tetapi tidak dihasilkan suara turbulen.

Suara normal paru berbeda sesuai dengan umur dari hewan, pola respirasi, ketebalan dinding dada, dan tempat dilakukan auskultasi. Intensitas suara pada hewan muda dan kurus adalah keras, jelas terdengar karena sedikit yang dapat melemahkan suara itu dan sedikit yang mempengaruhi alveoli. Pada hewan tua dan gemuk, suara normal paru sulit terdeteksi. Variasi dari suara normal paru dapat disebabkan oleh perubahan dalam pola respirasi seperti terengah-engah (meningkatkan intensitas), dan kelemahan neuromuskular (menurunkan intensitas). Suara abnormal dihasilkan dari proses patologis dalam trakeobroncial tree dan paru yang disebut dengan suara adventitious. Suara adventitious dapat bersifat diskontinyu (crackles) dan kontinyu (wheeze).

Crackles adalah suara eksplosif intermiten yang tidak teratur sehingga dikenal sebagai tone musical. Crackles sering dikarakterisasi sebagai suara kasar dan lembut. Suara crackles kasar seperti suara bubbling dan gurgling, sedangkan suara crackles lembut seperti suara velero atau tipe celophane. Salah satu mekanisme munculnya suara crackles kasar adalah meledaknya gelembung udara dalam cairan sekresi di saluran nafas, sedangkan crackles lembut dihasilkan oleh penyakit pada paru akibat beberapa saluran nafas tertutup saat inspirasi kemudian terbuka secara tiba-tiba. Suara crackles kasar ditemukan pada edema pulmonum, bronkitis dan bronkopneumonia yang diikuti terbentuknya cairan pada saluran nafas. Crackles lembut terdengar saat saluran terbuka secara tiba-tiba selama inspirasi, karena pencapaian keseimbangan yang cepat antara tekanan gas pada bagian atas dan bawah dari saluran nafas yang tersumbat.

Tabel 4. Penyebab Suara Paru Abnormal Pada Anjing Dan Kucing

CRACKLES	WHEEZE	Suara tak terdengar
Kasar	Inspiratori	Pneumotorak
Edema pulmonum berat	Obstruksi laring	Efusi pleura
Gagal jantung kiri	Laringitis nekrotik	Gagal jantung kanan
Hipoalbuminemia	Paralisis laring	Tumor
Bronkhopneumonia	Edema laring	Hipoalbuminemia
Trauma	Kolaps laring	Hemotorak
Lembut	Stenosis trakea	Chylotorak
Edema institialis pulmon um	Benda asing pada trakea	Pyotorak
Pneumonia institialis kronis	Kolaps trakea ekstratorak	Felin infectious peritonitis
Fibrosis institialis kronis	Compresión trakea intraluminal	Hernia diagframatika
	Tumor	Pemadatan paru
	Limpadenopati	Abses
	Ekspirasi	Granuloma
	Bronchitis	Tumor
	Alergi	Torsio lobus paru
	Brokopneumnia	Kegemukan
	Copd	Kelemahan neuromuskular
	Cacing paru	Paralisis diagfragma
	Cacing jantung

Wheeze adalah musical kontinyu atau suara whistling dihasilkan oleh terlepasnya udara melalui saluran yang sempit dan menyebabkan fibrasi regular atau penyempitan dinding saluran. Suara wheeze akan terdengar jika lumen dari saluran nafas menyempit. Jika kondisi baik, dinding saluran nafas akan bergetar diantara saat membuka dan menutup, akan menghasilkan suara kontinyu. Amplitudo, puncak, dan durasi wheeze tergantung atas velositi aliran udara dan bagian mekanis aliran udara.

Wheeze lebih umum terjadi pada saat ekspirasi dibandingkan inspirasi. Penyebab wheeze ekspirasi adalah bronkospasmus, edema mucosa, penumpukan mucus, benda asing, tumor. Wheeze inspirasi juga disebut stridor, hal ini berhubungan dengan stenosis saluran nafas atas, trakea, atau bronkhi.

Rencana Diagnosis

Sejarah dan Pemeriksaan Fisik

Gejala yang sering dilaporkan oleh pemilik hewan dengan suara paru abnormal adalah batuk, kesulitan bernafas, dan wheeze. Wheezing yang dijelaskan oleh pemilik sering suara abnormal yang berasal dari nasal dan saluran nafas atas. Pertanyaan yang teliti akan mengurangi kesalahan.

Pemeriksaan fisik dilakukan pada tempat tenang, sehingga auskultasi dapat dilakukan dengan baik. Suara paru dan jantung harus dievaluasi pada posisi hewan berdiri. Jika hewan terengah-engah, maka mulut pasien harus ditutup saat auskultasi. Suara mendengkur pada kucing dapat dihentikan sebentar dengan cara menekan laringnya atau dengan mengalihkan perhatian kucing dengan cara mengalirkan air pada kran. Suara berisik kulit dan rambut dapat dikurangi saat auskultasi dengan cara membasahi kulit dan rambut pada tempat auskultasi atau memegang kepala stetoskup dengan kuat menempel ke dinding dada. Kedua belah dada harus diauskultasi.

Evaluasi Laboratorium

Pemeriksaan laboratorium pada pasien dengan suara nafas abnormal sama seperti pada pasien batuk dan dispnea.

Terapi Simtomatis

Terapi simtomatis pada pasien dengan suara paru abnormal tidak perlu dilakukan.

5. BERSIN DAN LELERAN HIDUNG

Definisi

Bersin adalah reflek superfisial yang berasal dari reaksi pada lapisan membran mukosa pada rongga hidung dan dengan mudah dimunculkan oleh rangsangan kimia atau mekanis. Bersin terjadi akibat pengeluaran secara kuat udara melalui saluran nafas dengan kecepatan yang kencang. Hal ini untuk membantu membersihkan saluran nafas.

Leleran hidung adalah material yang dikeluarkan dari saluran nafas melalui nares eksternal. Leleran ini diklasifikasikan berdasarkan sifat fisik yaitu serous, mukoid, purulen, dan haemorrhagik, atau kombinasi dari ketiganya. Pakan dan larutan yang diminum juga dapat keluar bersama leleran itu saat bersin. Leleran hidung dapat secara unilateral atau bilateral, kontinyu atau intermiten, atau hanya saat bersin.

Patofisiologi

Impuls afferen dihasilkan dari rangsangan pada membran mukosa hidung, dihantarkan melalui nervus trigeminus menuju medula di otak, pada proses ini diawali dengan serentetan kejadian secara otomatis. Setelah terjadi inspirasi secara cepat lipatan vocal dan epiglotis akan tertutup, diikuti dengan kontraksi kuat dari abdomen, intercostae eksternal, dan otot respirasi yang lain yang mengakibatkan peningkatan tekanan udara di saluran respirasi. Kemudian lipatan vocal dan epiglotis terbuka secara cepat diikuti pelepasan udara sehingga terjadi bersin.

Bersin dan leleran hidung timbul diawali dengan kondisi yang secara langsung merangsang rongga hidung dan secara skunder karena rangsangan pada paring atau penyakit saluran respirasi bawah. Fungsi rongga hidung meliputi sebagai organ pencium, filtrasi, penghangat, melembabkan, dan tempat aliran udara. Rongga hidung tersusun atas tulang kartilago turbinate yang ditutupi oleh epitel pseudocolumnar bersilia. Epitel itu adalah epitel perifer respirasi primer dan pada organ pencium caudomedial dan caudodorsal. Lamina propria dari saluran respirasi tersusun atas glandula serous, mukous, dan campuran tubuloalveolar. Sel goblet juga ada di rongga hidung. Glandula bagian lateral hidung bersifat serous yang berfungsi sebagai mengatur panas. Sinus paranasal, frontal, dan spenoidal berhubungan dengan saluran nafas dan kadang-kadang dapat bertindak sebagai penyebab primer atau skunder timbulnya bersin dan leleran hidung.

Banyak kondisi peradangan pada mucosa hidung yang menyebabkan peningkatan sekresi glandula yang awalnya serous kemudian menjadi mukoid atau mukopurulen setelah ada infeksi bakteri. Hemorrhagi dapat terjadi karena ada trauma, coagulopati, dan kerusakan mukosa yang banyak vascularisasinya, erosi kronis, atau penyakit invasiv.

Penyingkiran dan Rencana Diagnosis

Kasus bersin dan leleran hidung pada anjing dan kucing dapat dilihat pada Tabel 5. Signalemen, sejarah, pengamatan fisik, dan karakterisasi fisik leleran hidung yang ada akan membantu dokter hewan dalam mendiagnosis dan pengobatan yang tepat.

Signalemen

Signalemen dari hewan akan membantu menentukan etiologi penyakit. Hewan muda, sangat tua, dan imunosupresif cendrung lebih mudah terserang penyakit. Gejala klinis yang berhubungan dengan penyakit kongenital sering dijumpai pada hewan muda. Breed brachycephalic sering menderita leleran hidung karena mudah menderita stenosis hidung atau dapat sebagai akibat skunder karena hewan tidak mampu mengendalikan ingesta atau sekresi respirasi di daerah paringeal akibat palatum lunak yang memanjang. Tumor hidung dan penyakit gigi sering dijumpai pada anjing dan kucing tua. Breed anjing médium dan besar dengan hidung yang panjang lebih sering menderita tumor hidung.

Sejarah

Bersin akut dan leleran hidung diikuti dengan leleran mata dipercaya karena infeksi virus. Abnormalitas kongenital atau gangguan paringeal akan terlihat gejalanya setelah makan dan minum. Bersin dan leleran hidung yang kambuh lagi setelah pengobatan antibiotik dipercaya sebagai rhinitis skunder karena bakteri dengan berbagai etiologi primer seperti trauma, alergi, benda asing, infeksi Jamur, dan tumor. Leleran hidung dengan sifat serous sampai mukoid secara bilateral dan kejadiannya bersifat musiman diikuti dengan gejala leleran mata itu sebagai akibat rhinitis alergi. Benda asing pada hidung menyebabkan bersin akut diikuti dengan gerakan pawing (menggaruk hidung) dan menggosokan hidung pada tanah oleh anjing. Infeksi jamur dan tumor dapat ditelusuri dari sejarah dari perkembangan leleran hidung dengan perubahan perkembangan yang pelan dari sifat serous kemudian menjadi mukopurulen dan berlanjut hemorrhagi. Hewan dengan sejarah penyakit menderita otitis media/ externa akan diikuti dengan leleran hidung dan bersin karena ada hubungan antara telinga media dengan nasoparing melalui tube eusthacian. Gagging sering dilaporkan oleh pemilik pada anjing yang menderita penyakit paring.

Pengamatan Fisik

Pengamatan fisik yang dilakukan pada penderita bersin dan leleran hidung meliputi pengamatan terhadap sistem respirasi, mata, dan rongga nasoparing. Pengamatan pada kepala dan mulut untuk mengetahui kelainan seperti stenosis nares, cleft palatum, fistula oronasal traumatik, otitis externa dan media, penyakit gigi, dan penjuluran palatum lunak, kemerahan oroparing dan tonsil, pembesaran tonsil dapat disebabkan oleh berbagai penyakit yang memicu terjadinya bersin dan timbulnya leleran hidung. Kerusakan palatum sering disebabkan oleh infeksi jamur. Fraktur tulang hidung juga dapat dipalpasi pada pemeriksaan kepala. Pneumonyssus caninum sering juga ditandai dengan pembesaran nares eksternal.

Gangguan saluran nafas atas seperti penyakit infeksi, alergi, deformitas kepala menyebabkan leleran mata. Feline viral rhinotracheitis menyebabkan ulcerasi cornea, anorexia, ptyalisme dan ulcerasi oral. Penyakit canine distemper dan cryptococcosis menyebabkan corioretinitis, sedangkan cryptococcosis juga menyebabkan uveitis anterior.

Leleran hidung unilateral diakibatkan oleh tumor, penyakit jamur, benda asing, abses akar gigi, dan fistula oronasal. Tumor yang agresif juga bisa menyebabkan leleran bilateral. Leleran bilateral sering karena penyakit infeksi, kelainan kongenital, penyakit paring, rinitis alergi. Suara pekak saat perkusi rongga hidung dan sinus para nasal dapat disebabkan oleh beberapa penyakit tetapi yang umum oleh jamur.

Suara parenkim paru dapat abnormal karena meluasnya infeksi jamur dan tumor, penyakit primer paru, dan penyakit pada saluran nafas atas dan bawah. Koagulopati menunjukan gejala perdarahan disekitar gangguan berupa perdarahan ptekie dan ekimose kulit dan membran mukosa.

Tabel 5. Penyebab Umum Bersin dan Leleran Hidung Anjing dan Kucing

Penyebab	signalemen	Sejarah	Pemeriksaan fisik	leleran	Rencana diagnosis
Kongenital
Stenosis nares	Anjing brachicephalic	Ngorok	Stenosis nares	Serous - mukoid	Pemeriksaan fisik
Cleft palatum	Muda, semua breed	Kesulitan menyusu, susu keluar dari hidung, leleran kronis setelah sapih	Palatum ada celah, suara paru abnormal	Ada pakan dan cairan, mukopurulen, bilateral	Pemeriksaan fisik
Pemanjangan palatum lunak	Anjing brachicephalic	Gagging dan snoring setelah makan	Kemerahan paring dan tonsil	Pakan atau cairan, serous – mukopurulen, bilateral	Pemeriksaan fisik
Dispagia	Semua breed, kongenital pada muda, dapatan pada yang tua	Batuk, gagging, seperti menelan sesuatu	Kemerahan paring, tonsil dan suara abnormal paru	Pakan atau cairan, serous – mukopurulen, bilateral	Pemeriksaan fisik, flouroscopi
Infeksi virus
FVR	Semua breed, semua umur, lebih umum pada muda	Kontak dengan hewan lain, vaksinasi tidak lengkap, anoreksia, ptylisme	Ulser mulut, konjungtivitis, suara paru abnormal, demam	Mukopurulen	FAT
Feline calicivirus	Semua breed, semua umur	Kontak dengan hewan lain, vaksinasi tidak lengkap, anoreksia, ptylisme Kontak dengan hewan lain, vaksinasi tidak lengkap, anoreksia, ptylisme	Ulser nasal dan oral, konjungtivitis, suara paru abnormal, demam	mukopurulen	Gejala klinis
Reovirus	Pada kucing semua breed dan umur	Gejala ringan	Demam jarang, gejala pada mata	Jarang ada	Laboratorium
Canine distemper	Semua breed dan umur	Kontak dengan hewan lain, vaksinasi tidak lengkap, banyak organ terserang	Demam, muntah, diare, suara paru abnormal, gejala saraf, gangguan mata, hiperkeratosis kaki	Mukopurulen	Gejala klinis, serologi, FAT, hitung darah lengkap
Bakteri
Berbagai spesies	Semua breed	Bersih kronis, respirasi seperti menyedot	Aliran udara menurun, perkusi pekak, anoreksia, dehidrasi	Mukopurulen, bilateral	Gejala klinis, sejarah, kultur
Chlamydia	Kucing semua breed, umur tapi sering pada muda	Kontak dengan hewan lain, tanpa gejala polisistemik	Konjungtivitis ringan	Serous – mukopurulen, bilateral	Sitologi
Mycoplasma	Semua breed dan umur	Tanpa gejala polisistemik	Konjungtivitis ringan	Serous	Sitologi
Jamur
Aspergillus dan penicillum	Semua breed, jarang pada bracicephalic	Progresif	Penurunan aliran udara, perkusi pekak, anoreksia	Mukoid, mukopurulen	Sitologi, kultur, serologi
Cryptococcus neoformans	Anjing dan kucing semua umur	Gejala nafas atas, polisistemik progresif	Demam, gejala saraf, suara paru abnormal, gangguan mata,	Mukoid – mukopurulen	Sitologi, kultur, serologi
Trichospora sp			Polyps
Rhinosporidium seebri			Polyps
Parasit
Linguatula serrata	Anjing semua umur	Bersin ringan	Tidak ada	Serous	Sitologi
Pneumonyssus caninum	Anjing semua umur	Bersin ringan	Tidak ada	Serous	Sitologi
Neoplasia	Umum pada anjing jarang di kucing, umum pada tua	Progresif	Penurunan aliran udara	Progresif dari mukopurulen – hemorrhagi	Sitologi, biopsi, radiografi
Alergi	Pada anjing dan kucing umur muda	Akut dan musiman	Konjungtivitis, dermatologik	Serous	Sejarah
Polyps	Kucing muda	Gagging, dispagia	Kemerahan paring, dan tonsil	Serous – mukopurulen	Pengamatan paring belakang
Penyakit gigi	Semua hewan	Halitosis, bersin paroksima, menggaruk muka	Fistula, kalkuli gigi, abses	Unilateral mukopurulen	Radiografi kepala
Otitis media	Semua hewan	Gejala ringan seperti otitis eksterna	Keratokonjungtivitis sicca	Kering dan keras	Otoscopi, kultur
Trauma	Semua hewan	Akut	Fraktur saat palpasi	Hemorrhagi	Sejarah, radiografi
Benda asing	Semua hewan	Bersin paroksima dan akut, menjulurkan kepala, menggoyangkan kepala	Nonspesifik	serous	Pemeriksaan fisik
Kelainan pembekuan	Semua hewan	Perdarahan tanpa trauma	Membran mukosa pucat	Hemorrhagi	Hitung platelet, waktu pembekuan, faktor VIII

Karakteristik Fisik Leleran Hidung

Leleran hidung serous timbul pada stadium awal penyakit pada rongga hidung. Leleran hidung serous yang kontinyu dan dalam jangka waktu lama sebagai tanda penyakit iritasi seperti alergi atau parasit. Pada penyakit infeksi virus diikuti infeksi skunder oleh bakteri leleran hidung bersifat mukopurulen.

Rencana Diagnosis

Prosedur diagnosis yang ditegakkan meliputi sitologi, serologi, kultur dan uji sensitivitas, pemeriksaan oral dan nasal dalam kondisi hewan terbius, radiografi nasal, uji FAT, koaglutinasi, endoscopi, dan biopsi.

Sitologi untuk mendeteksi jamur, sel tumor, atau parasit. Swab hidung secara langsung akan membantu diagnosis, jika penyakit lebih dalam maka perlu dilakukan flushing nasal dengan larutan steril. Aliran udara dihidung dapat disemikuantitatifkan dengan cara meletakan kaca didepan hidung dan dievaluasi terbentuknya embun pada kaca.

Uji FAT (flourescen antibodi teknik) untuk deteksi elemen virus distemper, feline viral rhinotrakeitis, clamidya, dan mycoplasma.

Kultur bateri dan jamur untuk deteksi jamur aspergillus dan penicillium, juga untuk diagnosis pasti dari bakteri penyebab.

Serologi untuk deteksi antibodi yang bersirkulasi terhadap aspergillus, penicillium, dan cryptococcus.

Uji koagulasi dilakukan jika ada perdarahan. Uji ini meliputi uji hitung platelet, waktu pembekuan darah, dan waktu perdarahan. Pada beberapa breed anjing , seperti doberman pincher yang sering mengalami perdarahan tiba-tiba, perlu dilakukan uji terhadap faktor VIII untuk membantu penyingkiran penyakit willebrand’s.

Terapi Simtomatis

Kontrol primer dari bersin adalah menyingkirkan penyebabnya. Perlu penajaman dalam keakuratan diagnosis. Keakuratan pengobatan tergantung ketepatan diagnosis. Pemberian obat untuk penyakit respirasi dilakukan dengan cara sistemik, topikal, dan nebulizasi.

Decongesta dapat digunakan secara topikal dan sistemik untuk pengobatan leleran hidung. Obat yang sering digunakan adalah oxymethazoline HCl topikal dan pseudoephedrine (30 mg setiap 8 – 12 jam secara oral). Obat ini menyebabkan vasokontriksi vaskular hidung karena efek simpatomimetiknya. Penyakit jantung sebagai kontraindikasi dari pengobatan ini. Efek samping dari penggunaan dekongestan topikal adalah terjadi kongesti, hal ini dapat ditangulangi dengan penggunaan setiap 2 – 3 hari.

Antibiotik dapat diberikan secara topikal, sistemik, atau melalui nebulizasi dan sangat baik untuk leleran yang mukopurulen. Beberapa peneliti melaporkan penggunaan obat tetes mata sangat baik untuk pemberisan intra nasal pada kucing. Masalah besar penggunaan antibiotik adalah kesulitan penetrasi obat ke dalam sekresi hidung yang tebal.

Kortikosteroid sangat baik untuk rhinitis alergi, penggunaannya kontraindikasi pada penyakit infeksi sehingga tidak baik untuk leleran mukopurulen.

Perdarahan hidung dapat dihentikan dengan kompres, 4-5 tetes 1: 50.000 epineprin secara intranasal, tetapi perlu diawasi karena berefek terhadap jantung.

VAKSINASI KUCING

2009-12-06T20:40:00.003+07:00

Program vaksinasi untuk kucing adalah sebagai berikut:

1. Vaksinasi Feline Panleucopenia, Rhinotracheitis, Calici dan Chlamydia pada umur 8-10 minggu dan 12-14 minggu.

2. Vaksinasi Rabies pada umur 20 minggu.

3. Pengulangan setiap 1 tahun sekali.

Perlu diperhatikan bahwa sebelum pelaksanaan vaksinasi, kucing harus diperiksa terlebih dahulu dan dinyatakan sehat oleh dokter hewan.

VAKSINASI ANJING

2009-12-06T20:39:00.002+07:00

Program vaksinasi anjing berikut adalah merupakan pedoman untuk pelaksanaan vaksinasi anjing. Untuk penjelasan lebih jelas silahkan menghubungi dokter hewan langganan anda:

1. Distemper - penyakit yang disebabkan oleh virus yang menyerang paru-paru, saluran pencernaan dan otak

2. Hepatitis – penyakit yang disebabkan oleh virus yang menyerang hati

3. Leptospirosis – penyakit yang disebabkan oleh bakteri pada sistem urinari

4. Parainfluenza – infectious bronchitis

5. Parvovirus – penyakit yang disebabkan oleh virus pada saluran pencernaan

6. Rabies – penyakit yang disebabkan oleh virus, bisa berakibat fatal pada hewan dan juga dapat ditularkan ke manusia (zoonosis)

7. Corona – penyakit pada saluran pencernaan

8. Bordetella – penyakit yang disebabkan oleh bakteri, sering disebut penyakit“kennel cough”

Anjing umur 6 minggu sampai 1 tahun

• DHLPP + Corona pada umur 6-8 minggu, 11-12 minggu dan 15-16 minggu

• Rabies pada umur 4 bulan (diulang satu tahun kemudian)

Anjing diatas 1 tahun

• Pengulangan DHLPP, Rabies dan Bordetella setiap tahun

SCABIES

2009-12-06T20:36:00.001+07:00

Scabies merupakan penyakit kulit yang sering ditemukan di Indonesia. Hal ini dikarenakan iklim tropis Indonesia sangat mendukung perkembangan agen penyebab scabies. Selain itu, kepekaan individu juga berpengaruh terhadap infestasi oleh agen. Kurang perhatian pemilik terhadap hewan dapat memicu terjadinya penyakit, misalnya hewan mengalami malnutrisi sehingga rentan terhadap penyakit atau pemilik kurang menjaga kebersihan hewan tersebut.Etiologi Penyebab dari scabies adalah tungau (mange) dari ordo Acarina, yaitu Sarcoptes scabiei var. canis pada anjing, dan Sarcoptes scabiei var. felis pada kucing. Sedangkan, penyebab scabies pada manusia adalah Sarcoptes scabiei var. hominis. Antara Sarcoptes scabiei satu dengan yang lain memiliki struktur yang identik tetapi secara fisiologis berbeda. Oleh karena itu, Sarcoptes scabiei dapat berpidah dan hidup pada induk semang yang lain meskipun dengan susah payah. Sehingga scabies tergolong penyakit zoonosis, karena dapat menular dari manusia ke hewan atau sebaliknya.

Gejala

Sarcoptes scabiei menyukai bagian tubuh yang jarang rambutnya, misalnya daerah perut. Hewan terlihat tidak tenang akibat rasa gatal dengan menggaruk atau menggosokkan pada benda keras. Rasa gatal tersebut timbul dari adanya allergen yang merupakan hasil metabolisme Sarcoptes scabiei. Selain itu, adanya aktifitas Sarcoptes scabiei misalnya berpindah tempat, juga dapat menyebabkan gatal. Rambut rontok dan patah-patah akibat sering menggaruk pada bagian yang gatal. Adanya lesi dengan tepi yang tidak merata disertai keropeng, kulit bersisik dan diikuti terjadinya reruntuhan jaringan kulit. Nafsu makan hewan turun, dan pada akhirnya akan diikuti penurunan berat badan sehingga hewan akan tampak kurus.

Diagnosa

Banyak penyakit kulit yang memiliki gejala yang mirip dengan scabies, diantaranya demodikosis, dermatitis allergica, eczema, ataupun infeksi jamur dan infeksi bakteri. Adanya rasa gatal disertai timbulnya lesi dan keropeng yang sulit untuk membedakan penyakit kulit satu dengan yang lainnya. Untuk menegakkan diagnosa, sebaiknya dilakukan kerokan kulit dan kemudian diperiksa dengan mikroskop.

Terapi

Ada dua cara pengobatan yang dapat digunakan, antara lain:

1. Injeksi. Obat ektoparasit yang biasa digunakan adalah avermectin, misalnya ivermectin secara subkutan (SC). Dosis yang dianjurkan adalah 1 ml untuk 15 – 20 kg berat badan dan diulang 10 -14 hari kemudian. Avermetin sebaiknya tidak diberikan pada anjing dengan umur yang terlalu muda, kurang dari 6 bulan dan ada beberapa anjing yang peka terhadap obat tersebut.

2. Dipping, yaitu memandikan hewan dengan tujuan pengobatan. Obat yang sering digunakan adalah Amitraz. 1 ml amitraz 5 % dilarutkan dalam 100 ml air untuk memandiakan hewan terinfestasi ektoparasit, dan diulang tiap minggu selama beberapa minggu hingga hewan sembuh.

BATUK PADA ANJING (CANINE INFECTIOUS TRACHEOBRONCHITIS / KENNEL COUGH)

2009-12-06T20:33:00.001+07:00

Kennel Cough atau Canine Infectious Tracheobronchitis adalah salah satu penyakit saluran pernafasan atas pada anjing yang biasa terjadi pada anjing muda. Gejala batuk ini terdengar seperti anjing berusaha mengeluarkan sesuatu yang tersangkut di tenggorokannya. Anjing yang terserang penyakit ini akan batuk setiap beberapa menit selama sehari penuh. Pada beberapa kejadian kadang tidak diikuti dengan perubahan status kesehatan anjing, suhu tubuh tidak meningkat dan kadang nafsu makan tetap bagus.Agen penyebab Infectious Tracheobronchitis ada beberapa macam, yang paling sering disebabkan oleh Virus Parainfluenza,Bordetella Bronchiseptica, dan Mycoplasma. Canine Adenovirus tipe II, reovirus, dan canine herpes virus juga pernah disebutkan sebagai agen penyebab penyakit ini.

Virus penyebab Infectious Tracheobronchitis yang paling sering menginfeksi adalah parainfluenza virus. Virus ini akan menyebabkan gejala ringan hingga 6 hari sampai adanya infeksi sekunder oleh bakteri. Untuk menghindari infeksi virus ini bisa dilakukan dengan vaksinasi.

Bakteri penyebab yang paling sering diisolasi dari anjing yang terserang penyakit ini adalah Bordetella bronchiseptica. Gejala klinis dari infeksi ini terjadi 2-14 hari setelah masuknya bakteri dalam tubuh. Jika tidak ada infeksi dari agen lain, gejala klinis akan hilang pada hari ke-10. Namun setelah infeksi teratasi, anjing penderita akan berusaha mengeluarkan bakteri yang keluar melalui dahaknya dalam waktu 6-14 minggu dan di masa inilah biasanya akan memudahkan anjing lain tertular. Parainfluenza dan Bordetella sering menginfeksi bersamaan pada kasus infectious tracheobronchitis, yang akan menimbulkan batuk yang akan sembuh dengan sendirinya dalam 14-20 hari.

Diagnosa

Diagnosa dari penyakit ini sering didasarkan pada gejala klinis dan sejarah adanya kemungkinan tertular dari anjing lain. Kultur bakteri, isolasi virus, dan gambaran darah bisa dilakukan untuk memastikan agen penyebab Kennel Cough, namun berdasarkan gejala klinis yang spesifik pada penyakit ini, uji-uji ini sangat jarang dilakukan.

Terapi

Ada dua pilihan terapi yang bisa dilakukan berdasarkan kejadian penyakit. Pada kasus yang ringan, bisa dilakukan dengan pemberian antibiotik ataupun tanpa antibiotik. Namun penanganan pada kasus ringan ini tidak berarti dapat memperpendek lamanya penyakit, dimana anjing penderita tetap akan dapat menularkan penyakit ini pada anjing lainnya. Sebagai tambahan bisa diberikan bronkodilatator seperti aminophylline atau obat-obatan pengurang batuk juga bisa diberikan pada kasus yang ringan.

Pada kasus yang lebih kompleks, dimana biasanya anjing hilang nafsu makan, deman, atau menunjukkan tanda-tanda pneumonia, bisa diberikan antibiotik. Antibiotik yang paling sering digunakan adalah doxycycline atau trimethropim sulfa. Namun demikian, banyak pilihan obat lain yang bisa digunakan. Pemberian steroid atau pengurang batuk tidak dianjurkan karena resiko imunosupresi, dimana kebutuhan steroid perlu kontinuitas untuk membersihkan cairan mukous pada pneumonia yang diderita. Bronkodilator dan bahkan terapi aerosol bisa diberikan.

Vaksinasi dan Pencegahan

Pencegahan yang paling baik adalah tidak mencampurkan anjing satu dengan anjing lainnya, terutama untuk anjing-anjing muda. Jika memang hal ini tidak bisa dihindari, pilihan kedua adalah melakukan vaksinasi. Anjing yang sudah divaksin akan terlindungi oleh beberapa agen penyebab trachebronchitis, terutama parainfluenza dan adenovirus.

DIAGNOSA PENYAKIT IKAN

2009-12-06T20:30:00.001+07:00

Gambaran Umum Diagnosa Penyakit Ikan
Definisi penyakit dalam patologi ikan Penyakit didefinisikan sebagai suatu keadaan fisik, morfologi, dan atau fungsi yang mengalami perubahan dari kondisi normal karena beberapa penyebab, dan terbagi atas dua kelompok yaitu penyebab dari dalam (internal) dan luar (eksternal). Penyakit ikan umumnya adalah eksternal.
Penyakit internal : genetik, sekresi internal, imunodefisiensi, saraf dan metabolik.
Penyakit eksternal :
1). Non patogen
* Penyakit lingkungan :suhu dan kualitas air lainnya (pH, kelarutan gas, zat beracun).
* Penyakit nutrisi : kekurangan nutrisi, gejala keracunan bahan pakan.
2). Patogen; bersifat parasit dan terdiri atas empat kelompok yaitu :
* Penyakit viral
* Penyakit jamur
* Penyakit bakterial
Tabel 1. Karakteristik setiap kelompok patogen Karakteristik Virus Bakteri Jamur Parasit Karakteristik penyakit infeksi pada ikan Ikan merupakan salah satu hewan air yang selalu bersentuhan dengan lingkungan perairan sehingga mudah terinfeksi patogen melalui air. Infeksi bakteri dan parasit tidak terjadi pada hewan darat melalui perantara udara, namun pada ikan sering terjadi melalui air. Pada budidaya, air tidak hanya sebagai tempat hidup bagi ikan, tapi juga sebagai perantara bagi patogen. Istilah penting penyakit infeksi pada ikan Istilah penting yang seringkali digunakan dalam penyakit infeksi ikan adalah sebagai berikut :
* Epidemiologi : ilmu yang mempelajari hubungan berbagai faktor yang mempengaruhi frekuensi dan penyebaran penyakit pada suatu komunitas.
* Penyebaran vertikal : penyebaran penyakit dari suatu generasi ke generasi selanjutnya melalui telur.
* Penyebaran horisontal : penyebaran penyakit dari ikan satu ke ikan yang lain pada kelompok ikan dan waktu yang sama.
* Carrier : hewan yang membawa organisme penyebab penyakit dalam tubuhnya, namun hewan tersebut terlihat sehat sehingga menjadi pembawa atau penyebar infeksi.
* Vektor : hewan yang menjadi perantara organisme penyebab penyakit dari inang yang satu ke inang yang lain. Contoh : siput, burung.
* Patogenisitas : kemampuan untuk dapat menyebabkan terjadinya penyakit.
* Virulensi : derajat patogenisitas suatu mikroorganisme.
* Kisaran inang : kisaran hewan-hewan yang dapat diinfeksi oleh patogen.
Tabel 2. Patogen pada ikan budidaya air tawar di Indonesia Spesies Ikan Virus Bakteri Jamur Parasit Prosedur diagnosa di lapangan
1. Pengukuran panjang dan berat ikan.
2. Pengamatan tanda-tanda luar pada permukaan tubuh dan insang.
3. Gunting lembaran insang dan ambil lendir tubuh untuk mendeteksi parasit di bawah mikroskop.
4. Ambil contoh darah dari sirip dada menggunakan jarum suntik untuk pembuatan preparat apusan darah dengan menggunakan pewarnaan Giemsa.
5. Isolasi jamur dengan menggunakan agar GY jika diduga terjadi infeksi jamur. vi. Isolasi bakteri dari sirip atau insang dengan menggunakan agar cytophaga, jika diamati adanya insang atau sirip yang membusuk.
6. Isolasi bakteri dari luka dengan menggunakan agar TS atau BHI, jika ikan memiliki borok atau ada pembengkakan pada permukaan tubuh.
7. Bedah ikan dengan peralatan bedah yang bersih untuk membuka rongga perut dan amati tanda-tanda internal.
8. Isolasi bakteri dari hati, ginjal dan limpa dengan menggunakan agar TS atau BHI. x. Pembuatan preparat limpa pada kaca preparat dengan pewarnaan Giemsa untuk mendeteksi infeksi bakteri.
9. Fiksasi setiap organ dengan larutan formalin 10°I° berpenyangga fosfat- untuk histopatologi dan dalam etanol 70% untuk uji PCR. Pekerjaan di laboratorium Pekerjaan yang paling penting bagi ahli penyakit adalah mendiagnosa penyakit. Jika diagnosanya salah, maka penanganannya juga akan salah. Bila terlalu lama untuk mendiagnosa penyakit, ikan mati sebelum pengobatan dilakukan, diagnosa harus tepat dan cepat. Prosedur diagnosa adalah sebagai berikut : pertama, coba isolasi patogen dari ikan yang sakit (kecuali untuk infeksi oleh virus); kedua, patogen yang diisolasi diinfeksikan ke ikan yang sehat. Bila diduga virus, larutan yang sudah disaring dengan menggunakan saringan 0,45 µm homogen, diinfeksikan ke ikan yang sehat. Jika ikan yang sekarat (moribund) dengan gejala seperti ikan yang sakit tersebut, hal ini membuktikan bahwa yang diisolasikan tersebut merupakan penyebab penyakit. Dengan demikian, penyebab penyakit teridentifikasi sebagai spesies yang sama dengan patogen sebelumnya. Diagnosa penyakit ikan dapat menjadi lengkap dengan adanya identifikasi penyebab penyakit. Metode pemeriksaan untuk konfirmasi diagnosa berbeda untuk setiap jenis patogen, virus, bakteri, jamur dan parasit. Tindakan penanganan
* Penyakit viral : jika ikan terinfeksi oleh virus sangatlah sulit untuk diobati. Ada dua cara tindakan pencegahan yaitu membersihkan virus penyebab penyakit dari lingkungan clan meningkatkan kekebalan ikan terhadap viral. Tindakan pencegahan pertama, desinfeksi semua wadah clan peralatan, seleksi incluk clan telur bebas virus. Tindakan selanjutnya bila memungkinkan adalah meningkatkan kualitas telur, penggunaan vaksin clan immunostimulan atau vitamin. Diantara tindakan penanganan yang ada, vaksin merupakan tindakan yang paling efektif untuk mencegah penyakit viral. Sampai sekarang, vaksin untuk beberapa penyakit viral telah dikembangkan sebagai komoditas komersial, tapi untuk virus herpes koi belum dilakukan. Di masa yang akan datang, vaksin terhadap virus herpes koi dapat dikembangkan.
* Penyakit bakterial : penyakit bakterial dapat diobati dengan antibiotika. Namun, penggunaan antibiotika yang tidak tepat menghasilkan efek yang negatif. Itulah sebabnya pemilihan antibiotika yang tepat merupakan pekerjaan yang paling penting untuk masalah infeksi bakteri. Pemilihan antibiotika dilakukan berdasarkan hasil uji sensitivitas obat. Antibiotika dapat mengobati dengan cepat ikan yang terinfeksi dengan bakteri, namun dapat menyebabkan timbulnya bakteri yang resisten terhadap antibiotika. Dari hal tersebut, pengembangan vaksin terhadap setiap penyakit bakterial sangatlah penting.
* Penyakit jamur : sampai sekarang belum dikembangkan tindakan penanganan untuk infeksi jamur pada hewan air. Jadi pencegahan tindakan yang dapat dilakukan. Spora yang berenang di air untuk menemukan inang menunjukkan sensitivitas terhadap beberapa zat kimia.
* Penyakit parasitik : pada umumnya ektoparasit dapat ditangani dengan zat kimia. Namun, telur dan siste memiliki resistensi terhadap zat kimia. Berdasarkan keberadaan parasit, pengobatan kedua harus dilakukan setelah spora atau oncomiracidium menetas. Untuk menentukan jadwal pengobatan untuk setiap parasit, studi siklus hidup parasit sangatlah penting.

DIARE PADA PEDET

2009-12-06T20:27:00.001+07:00

Bulan Desember barangkali adalah salah satu bulan yang cukup mengerikan bagi peternak sapi dan Dokter Hewan. Bukan karena banyak tanah longsor dan banjir dimana-mana, tapi karena banyak masalah kesehatan sapi yang membutuhkan penanganan cepat dan tepat. Kali ini kita akan membahas permasalahan yang rawan menyerang pedet karena makhluk kecil ini sangat sensitif dan rawan mengalami kematian pada setiap kasusnya.Salah satu masalah utama pada pedet yang cukup meresahkan adalah adalah diare yang dapat berakibat kematian jika terjadi dalam beberapa hari. Kematian in disebabkan karena dehidrasi yang terjadi terus menerus. Jika pedet kehilangan cairan tubuhnya lebih dari 15%, maka kematian akan terjadi karena pedet mengalami stress yang luar biasa.
Banyak cara sudah disarankan untuk mencegahnya dengan manajemen kandang pedet yang baik, kering, terang, terhindar dari infeksi sekunder, penyemprotan pusar post calving menggunakan antiseptik setiap hari dan sebagainya.
Berikut beberapa sistem manajemen pemeliharaan pedet baru lahir untuk mencegah diare dan penanganan pedet diare yang sudah umum direkomendasikan :
1. Memberi kolostrum secepat mungkin (paling lambat 5 jam setelah lahir) sebanyak
1-2 liter dan ditingkatkan 1 liter setiap harinya
2. Melakukan penyemprotan tali pusar dengan menggunakan antiseptik dan dilakukan 2 kali setiap hari pada hari berikutnya hingga tali pusat kering atau putus
3. Jika tersedia, digunakan juga penjepit tali pusar (umbilical cord clamp) hingga tali pusat lepas dengan sendirinya.
4. Pedet dipelihara secara individual hingga minimal 2 minggu pertama untuk mengamati pola konsumsi, kondisi umum, kondisi kotoran dan sebagainya
5. Setelah 1 minggu, pedet mulai dilatih makan rumput yang dikeringkan (hay, sebagai free choice) untuk merangsang pertumbuhan rumen dan keberadaan makroflora pada rumen
6. Air minum tersedia secara adlibitum
7. Pemberian oralit dan obat antidiare (penulis menemukan obat antispasmodik yang biasa digunakan untuk manusia juga cukup efektif untuk pedet, dosisnya sama dengan dosis untuk manusia dewasa)
8. Penggunaan antibiotik spektrum luas (seperti penicillin atau amoxicillin + asam klavulanat atau bisa juga digunakan trimetoprim dan preparat sulfa dosis rendah)
Meskipun manajemen ini sudah dilakukan, peluang terjadinya diare pada pedet tetap ada sehingga diperlukan metode lainnya untuk lebih meminimalkan kejadian diare ini. Menurut Hemingway (1991), keberadaan asam askorbat dalam darah pedet pada level tertentu dapat membantu pencegahan kejadian diare pada pedet. Permasalahannya adalah, untuk mendapatkan preparat asam askorbat murni tidaklah mudah. Untungnya kita tidak perlu khawatir lagi karena asam askorbat juga bisa didapat dalam Vitamin C yang dengan mudah bisa kita dapatkan.
Pada tahun 2004, Shinduran dan Albay mempublikasikan hasil penelitannya yang menyatakan bahwa pemberian Vitamin C pada pedet dapat membantu meningkatkan level asam askorbat pada darah dan secara otomatis dapat membantu mencegah diare pada pedet.
Secara alami, asam askorbat memang sudah ada pada darah pedet, namun hemingway menemukan bahwa asam askorbat baru muncul pada hari kedua sehingga masih ada permasalahan tentang suplai asam askorbat pada hari lahirnya pedet.
Dalam publikasinya, Shinduran dan Albay menyatakan bahwa mereka melakukan penelitian pada sejumlah pedet di Turki untuk mengetahui efek pemberian vitamin C dengan berbagai level secara bertahap pada pedet. Mereka mengukur level asam askorbat pada masing-masing pedet dan mereka berkesimpulan bahwa memberikan vitamin C sebanyak 2,5 gram peroral pada saat lahir pada pedet dapat menambah level asam askorbat hingga 7 hari dan dapat mencegah diare pada pedet. Kabar baik ini setidaknya dapat dijadikan referensi untuk mencegah kejadian diare pada pedet.

DIABETES MELLITUS PADA ANJING

2009-12-06T20:23:00.003+07:00

Saya yakin bagi pembaca pasti akan bertanya, apakah anjing juga bisa menderita diabetes mellitus? Jawabannya ya. Curigai anjing menderita diabetes bila semakin kurus namun lebih kelaparan dan haus, lebih sering kencing dengan frekuensi dan jumlah yang banyak.
Pada manusia, diabetes dikenal dalam 2 gambaran klinis. Juvenile yaitu pada saat pertumbuhan, biasanya umur muda, ketosis-prone, hipoinsulinemia, insulin dependent, yang juga digolongkan sebagai tipe I. Sedangkan tampilan klinis yang lain adalah pada umur dewasa atau tua, ketosis-resistant, non insulin dependent, noninsulinemia, gemuk, yang juga digolongkan sebagai tipe II. Dengan berkembangnya teknik pemeriksaan insulin pada anjing, telah dibandingkan tipe diabetes mellitus pada anjing dan manusia. Tipe diabetes pada anjing yang paling sering adalah diabetes mellitus yang mirip dengan diabetes mellitus tipe I pada manusia, yaitu insulin dependent diabetes. Beberapa kasus juga diduga menderita diabetes tipe II.
Sebagian besar anjing penderita diabetes mengalami hipoinsulinemia absolut dan relative, gangguan sekresi insulin, membutuhkan injeksi insulin dan ada kecenderungan mengalami ketoasidosis. Penyakit ini dapat terjadi pada anjing semua umur.
Apa gejala anjing yang menderita diabetes? Gejala utama yang tampak adalah anjing sering makan, minum dan sering kencing atau polifagia, polidipsia dan poliuria. Hal ini karena gula darah tidak dapat masuk ke dalam sel sehingga tubuh “selalu merasa lapar”, dan tingginya kadar gula darah akan menyebabkan glukosuria (air kencing mengandung gula) dan poliuria akibat osmotik diuresis karena tingginya gula dalam urine. Gejala lain adalah kehilangan berat badan. Kasus lain kadang juga diikuti adanya kebutaan akibat pembentukan katarak yang sebetulnya merupakan akibat sekunder berkaitan dengan keparahan dan durasi hiperglikemia.
Curigai anjing menderita diabetes mellitus bila anjing menunjukkan gejala anjing kencing lebih sering dan lebih banyak dari biasanya, lebih banyak makan dan cepat lapar namun justru kehilangan berat badan dan adanya gejala kebutaan serta tampak adanya pembentukan katarak. Pada pemeriksaan kadar glukosa darah sangat tinggi (lebih dari 200 mg/dl) meski dalam keadaan puasa, dimana seharusnya 70 sampai 110 mg/dl. Kasus yang saya temukan pada anjing bahkan mencapai angka lebih dari 650 mg/dl kadar gula puasa dan lebih dari 720 mg/dl kadar gula pasca makan. Bisa dipastikan bila anjing dengan gejala polifagia, polidipsia dan poliuria dengan hasil pemeriksaan kadar gula darah tinggi dan glukosuria adalah menderita diabetes mellitus. Namun tidak, bila hasil pemeriksaan gula darah lebih rendah dari 150 mg/dl dan tidak ditemukan glukosuria. Glukosuria baru terjadi bila kadar gula darah 180 sampai 220 mg/dl atau lebih.

SWINE INFLUENZA

2009-12-02T18:54:00.001+07:00

Pendahuluan

Swine influenza (SI) atau Flu Babi adalah penyakit saluran pernafasan yang bersifat akut dan sangat menular yang disebabkan oleh virus influenza tipe A. Manifestasi klinis dari SI ini dapat ditentukan oleh infeksi sekunder pada babi yang sakit. Babi merupakan inang utama virus SI klasik (terdapat laporan adanya infeksi pada manusia, akan tetapi virus SI ini tidak mudah menyebar ke populasi manusia, akan tetapi kematian bisa terjadi pada orang-orang yang mempunyai kelainan pada sistem kekebalan tubuhnya).

SI umumnya dapat ditemukan di Amerika Serikat, Mexico. kanada, Amerika Selatan, Eropa, Kenya, Jepang, Taiwan dan beberapa negara di Asia Timur.

Penyebab

Swine Influenza Virus (SIV) adalah orthomyxovirus grup Influenza A dengan hemaglutinin antigen H1 dan Neuraminidase antigen N1 (H1N1), Pada saat ini, subtipe yang baru pernah dilaporkan yaitu H3N2 dan H1N1. Virus Influenza B dan C pernah diisolasi dari dari babi, akan tetapi virus-virus ini tidak menyebabkan penyakit yang klasik. SIV tidak bisa bertahan hidup lebih dari 2 minggu kecuali di kondisi yang dingin dan virus ini mudah mati dengan disinfeksi biasa.

Transmisi dan Epidemiologi

Di Amerika Utara, Wabah biasanya terjadi pada musim gugur dan dingin. Di daerah yang lebih hangat, infeksi dapat terjadi kapanpun. Biasanya wabah dimulai dengan adanya kasus pada satu atau dua hewan dan kemudian menyebar secara cepat dalam kelompok hewan tersebut, melalui aerosol dan kontak antar babi. SIV dapat bertahan dalam babi kariers sampai kurang lebih 3 bulan, dan virus ini dapat ditemukan pada hewan yang secara klinis normal diantara wabah. Pada kelompok babi yang secara antibodi positif, wabah dapat terjadi kembali ketika titer antibeodi menurun. Lebih dari 40% babi dalam kelompok akan menunjukan hasil positif antibodi. babi karier biasanya menjadi penyebab masuknya SIV kedalam kelompok babi atau negara yang tadinya bebas SIV.

Gejala Klinis

Wabah yang klasik terjadi sangat cepat, ditandai dengan penyebaran yang cepat di dalam kelompok babi, biasanya terjadi dalam jangka waktu 1-3 hari. Gejala klinis utama adalah depresi, demam sampai 42oC, anoreksia, batuk, kesulitan bernafas, kelemahan, lesu, serta adanya cairan pada mata dan hidung. Angka kematian akibat SI sekitar 1-4%. Penyakit biasanya mulai menghilang sekitar 3-7 hari dalam infeksi yang tidak komplit. Virus masih akan tetap bersirkulasi diantara babi ketika gejala klinis mulai tertekan dengan adanya peningkatan tingkat kekebalan. Kerugian ekonomi terjadi akibat adanya keterlambatan dalam mencapai berat badan yang diinginkan. Adanya angka kematian terutama pada babi muda, menurunnya tingkat fertilitas dan kemungkinan adanya aborsi pada kebuntingan tua bisa mengikuti wabah pada kelompok babi yang tidak kebal.

Diagnosis

Dugaan kasus dapat dilakukan melalui temuan klinis dan patologis, akan tetapi konfirmasi dapat dilakukan hanya melalui isolasi virus atau temuan adanya antibodi spesifik terhadap SIV.

Pengobatan dan Pengendalian

Tidak ada pengobatan yang efektif, antimikrobial dapat diberikan untuk mengurangi infeksi bakteri. Ekspektoran dapat membantu mengurangi gejala pada kelompok ternak yang terkena wabah. Vaksinasi dan Persyaratan impor ketat adalah satu-satunya tindakan pencegahan yang baik. Pengelolaan peternakan yang baik, serta babi yang tidak stress, terutama akibat kepadatan babi dan debu dapat membantu mengurangi kerugian.

Vaksin komersial yang killed yang berisi subtipe H1N1 dan H3N2 nampaknya dapat memberikan respon kekebalan yang kuat.

AVIAN MALARIA

2009-11-14T23:44:00.001+07:00

Nature of the disease

Avian malaria is caused by parasites of the Plasmodium genus. The disease is transmitted by mosquitoes.

Classification

SPC List D

Susceptible species

Some 65 Plasmodiun sp. have been isolated from over 1,000 different species of birds. Few of the Plasmodium sp. which have been identified appear to be natural parasites of domestic poultry. A number of other species of Plasmodia, that occur primarily in passerine birds, can infect or have been experimentally transmitted to the domestic fowl

Distribution

Plasmodium spp. pathogenic for domestic poultry are found mainly in Africa, Asia and South America. It has been recently identified in American Samoa.

Clinical signs

Avian malaria produces a wide range of effects in avian hosts, from no apparent clinical signs to severe anaemia and death. Pl. gallinaceum, Pl. juxtanucleare and Pl. durae appear to be the most dangerous for poultry, producing up to 90% mortality.

Post-mortem findings

Intense and severe anaemia is the main finding. The associated tissue hypoxia can produce tissue necrosis. Hypertrophy of the spleen and the liver.

Differential diagnosis

Other causes of anaemia in poultry include:

Iron deficiency
Egg drop syndrome
Leucocytozoonosis
Spirochaetosis
Blood sucking external parasites e.g. fleas, mites, ticks and bugs
Chicken anaemia agent
Bbig liver and spleen disease
Coccidiosis

Specimens required for diagnosis

Blood smears and impression smears of liver and spleen should be collected and stained with Leishman’s, Giemsa’s, or Wright’s stains for direct microscopic observation.

Transmission

Avian malaria is transmitted by mosquitoes. Avian plasmodia characteristically develop in culicine mosquitoes – Culex and Aedes.

Risk of introduction

Avian malaria could be introduced through imports of infected birds, or via migrating wild birds. Quarantine and import controls should be used to reduce the risk of importing infected birds.

Control / vaccines

in drinking water, Chloroquine is efficient as well as Sulfamides (although they are inefficient in Mammals).Control depends upon breaking the mosquito transmission cycle, by eradication or reduction of mosquitoes, or by isolating the poultry flock by mosquito-proof housing.

References

BUSSIERAS J, CHERMETTE R, Protozoologie In Parasitologie Vétérinaire, Ecole Nationale Vétérinaire D'Alfort, 1992, p 157.
JARVI SI et al. Detection of avian malaria (Plasmodium spp.) in native land birds of American Samoa, Conservation Genetics 4 (5): 629-637, 2003
Plasmodium infection, In Merck Veterinary Manual, National Publishing Inc. Eight ed, 1998, Philadelphia, p 1883

PROTEIN SCIENCES (BIOMOLECULAR)

2009-11-14T23:17:00.002+07:00

Protein Purification is a popular protein science service offered by Blue Sky Biotech.
Other protein science services included but are not limited to the following:

FPLC: IEC, IMA, SEC, AC, Buffer-exchange, etc.
Microsome preparation
Tissue/organ extraction and purification
Antibody purification
Development of multi-step protocols
Activity validation (where applicable)
QC supported by MASS Spec service
QC by Western Blot and SDS PAGE

Purified recombinant protein is indispensable for drug discovery. In the early stages of drug discovery, recombinant protein is used for target validation, enzyme characterization, high-throughput screening (HTS), and structural study. In order to understand a disease target, pharmaceutical scientists must study its interaction with substrates. For this purpose, researchers need active protein free of impurities which could interfere with their study of its mechanism. Purity and activity of the recombinant protein are essential: a pure, active enzyme gives a clean signal and reproducible results.
Blue Sky employees have worked in the Protein Science department of a major pharmaceutical company. This group and others like it serve almost as "core facilities" in that they provide made-to-order proteins for enzyme characterization, structural study, and HTS. Our experience in this environment gives us a unique understanding of the requirements for quality, purity, and activity of recombinant proteins. Customers of Blue Sky may rest assured that all purified proteins provided by this firm will meet the most exacting standards.
Protein expression, purification, and characterization are very precise, difficult disciplines. We at Blue Sky have the expertise to generate the high-quality protein reagents which you need.

Our most common protein services include the following:

Generation of expression strains in E. coli and yeast ( S. cerevisiae, P. pastoris, S. pombe) systems; expression of recombinant protein in E. coli and yeast systems
Generation of recombinant baculoviruses and protein expression in insect cells with he baculovirus system
Protein purification by affinity, ion-exchange, and size-exclusion chromatography
Protein analysis by gel electrophoresis and mass spectrometry

Other, less-common services include the following:

Expression of recombinant protein in mammalian cells by plasmid- and retrovirus-based systems
Protein purification by reverse-phase HPLC and other methods of chromatography
Protein analysis by 2-D electrophoresis, N-terminal sequencing, and other methods

Blue Sky specializes in baculoviral services. Contact us now to get more information about our baculoviral services.
Insect cells are the preferred module for high-level recombinant protein expression of many disease-relevant protein families. Several popular kit systems exist in the protein expression marketplace, however all common systems utilize baculovirus as a vector for host infection and protein production.
The most challenging element of baculoviral-mediated (baculo) protein expression is low batch-to-batch (lab-to-lab) replicability. Blue Sky has developed a multi-component system which employs Infection Kinetics Monitoring (IKM) technology. This system compiles a suite of real-time cell population measurements, read during the course of viral infection.
In tandem with standard scouting measures (such as Western Blot), IKM substantially decreases the guesswork associated with scale-up baculo expression. This system also obviates the need for laborious baculoviral titration. IKM makes baculo expression more predictable.

Gene synthesis
Sub cloning and plasmid construction
Vector construction and modification
Construct generation
Site-directed mutagenesis
Genetic (cDNA) cloning
In vitro transcription
Protein expression scouting
Plasmid preparation

Molecular biology drives modern drug discovery. Drug screening, target validation, and structural studies all require recombinant DNA constructs and proteins.
Though molecular biology techniques are extremely common and widely-used, they can also be very tiresome, tricky, time-consuming, and frustrating. In addition, equipment for molecular biology is extremely expensive. In many cases, it is simply more economical to outsource this work than to perform it in-house.
Blue Sky will help you to fulfill your needs for recombinant DNA constructs and for other molecular biology services. From the initial cloning of your gene of interest to the development of multiple constructs and site-directed mutagenesis, we will provide a comprehensive suite of services to move your project along quickly and smoothly.
Our most common services include the following:

Genetic (cDNA) cloning
Subcloning and plasmid construction
Vector construction and modification
Construct generation
Site-directed mutagenesis
Generation of recombinant baculoviruses
Transient and stable transfection of mammalian cells

Scale-up of E. coli in 10-L/55-L bioreactors
Scale-up of yeasts in multiple 10-L bioreactors
Scale-up of insect-cell and mammalian expression in bioreactors
Optimization of expression in bioreactors
Process development for fermentation
Perfusion and microcarrier culture
Batch, fed-batch, and continuous culture
Intracellular and secreted products
Stable Cell line production
Membrane preparation

Life for the protein scientist would be very easy if every protein could be purified in hundred-milligram quantities from small-scale flask cultures of E. coli.Unfortunately, many proteins require expression in animal-cell systems and culture scale-up.
Blue Sky scientists will take care of the frustrating, laborious work of tissue culture- our clients can save their time for true scientific investigation instead of spending hours ensuring that cultures stay healthy and contamination-free. We have a great deal of experience with insect-cell lines, and in our past work we have grown dozens of different mammalian cell lines.
In similar fashion, Blue Sky will save its clients a great deal of time with bioprocess scale-up services. Using bioreactors, Blue Sky scientists will quickly deliver large quantities of cell paste or conditioned medium.
Our most common services include the following:

Insect-cell culture (Sf9, Sf21, HighFive, Drosophila Schneider S2, and other lines)
Production and amplification of recombinant baculoviruses in insect cells
Process development in baculovirus expression
Culture, transient and stable transfection, and subcloning of common mammalian cell lines (293, CHO, COS, 3T3, HeLa, and others.
Scale-up of bacterial and yeast cultures in laboratory-scale (up to 10-L) bioreactors
Scale-up of insect-cell and mammalian cultures in laboratory-scale (up to 10-L) bioreactors
Monoclonal antibody production from established hybridoma lines

Less-common services:

Culture, transient and stable transfection, and subcloning of less-common mammalian cell lines
Perfusion culture of animal cells

Adult Stem Cells Show Wider Potential Than Previously Thought

Chemists are developing new insights and techniques in an effort to expand the therapeutic potential of stem cells, which includes possible treatments for Parkinson's disease, diabetes, spinal cord injury and other devastating conditions.

Embryonic stem cells are the most versatile stem cells, capable of being transformed into any other cell type, depending on their desired therapeutic use.
Now, researchers at Northwestern University have found new evidence that hematopoietic stem cells, a type of adult stem cell derived from the bone marrow that gives rise to blood cells, are capable of undergoing more diverse transformations than previously thought and could be transformed into a wide variety of tissue types, not just blood cells.
In recent laboratory tests, human megakaryocytes (bone marrow cells that produce blood platelets that are responsible for blood clotting) derived from adult hematopoietic stem cells were, for the first time, reprogrammed into neutrophil-like cells similar to the white blood cells that are responsible for fighting infections, according to study leader E. Terry Papoutsakis.
Insights from this study could help guide similar adult stem cell transformations in other cell types in the future, he says.