Date: 2004 l  Full Text

Summary : Two snail species belonging to genus Lymnaea, L.auricularia and L.gedrosiana, were collected from 6 different districts of Shadegan area of Khoozestan. Eight percent of the total collections of the snails revealed the occurrence of larva in them. The prevalence of larva within the snails varied in different districts may be due to different geoclimatic conditions and availability of fresh water. Seasonal prevalence of snails and factors affecting snail populations including water temperature, light, water depth and pH under field conditions were also studied.

Keywords : prevalence, trematod, ecology, Lymnaea, Iran

Date: 2004 l  Full Text

Summary : Alpha toxin derived from Clostridium perfringens was used for diagnosis of Streptococcus agalactiae (St.agalactiae) by rapid and spot CAMP tests. The selected Cl.perfringens strain was cultured in optimized conditions; the supernatant of culture was concentrated by ultra filter and purified by DEAE cellulose chromatography. The efficacy of both purified and crude a-toxins were examined by rapid and spot CAMP tests. The result of this study indicates that there is no significant difference between the purified and crude enzyme in identification of St.agalactiae. The specificity of the enzyme was confirmed by testing of different Streptococcus spp. The run time require for spot and rapid CAMP tests using a-toxin were between 10-90 minutes and 4-6 hours, respectively, whereas the traditional test needs 18-24 hours for running.

Keywords : Streptococcus agalactiae, Clostridium perfringens, a-toxin, CAMP

Date: 2004 l  Full Text

Summary : The effect of colistin sulfate on reducing Salmonella enteritidis (S.enteritidis) infection in broilers and contamination from broiler carcasses was evaluated. 40000 birds in two separate houses were considered. Colistin sulfate was added in to the feed of the test group as 100g containing 1,200,000IU/ton of feed for the whole period (56 days). To isolate S.enteritidis, samples were taken from different parts of the intestine and cultured in Selenite broth and then on SS agar plates. The suspected colonies were isolated and identified by biochemical and serological tests. It is conducted that the addition of the above mentioned amount of this antibiotic in to the broiler feed could decrease the rate of the infection of flocks and contamination of carcasses with S.enteritidis. The results also indicate that due to addition of colistin sulfate, the live weight gain increases by 14% and the feed conversion rate improves by 8% in this study.

Keywords : Salmonella enteritidis, colistin sulfate, broiler, Iran

Date: 2004 l  Full Text

Summary : 3450 bovine from different breeds and ages were clinically examined for the presence of arthritis. 120 cases showed macroscopic evidences of arthritis. Mycoplasma spp were isolated from synovial fluid of 21 affected animals. In addition to Mycoplasma spp. Arcanobacterium pyogenes and Staphylococcus epidermidis were isolated from 2 cases. The synovial fluid was markedly increased, straw color, turbid and mostly contained thick confluent fibrin. Thickening of the synovial membrane, villus hyperplasia, loss of the synovial cells, infiltration of leukocytes, hyperemia and edema of synovial membrane and periarticulare tissues were seen. Isolation of Mycoplasma from the bovine with arthritis indicates the importance of the organism as causative agent of the disease.

Keywords : arthritis, bovine, Mycoplasma spp.

Date: 2004 l  Full Text

Summary : The virulence of Pasteurella multocida (P.multocida) serotype A1 for chickens and mice was determined. Groups of chickens and mice were exposed intramuscularly and intraperitoneally to various concentration of P.multocida broth culture, respectively. This strain was highly virulent for chickens so that those exposed to only 7c.f.u. of the organism died in less than 24 hours. Groups of mice exposed to the virulent strain died during 48 hours post inoculation. Microbiological examination resulted in the isolation of P.multocida from exposed chickens and mice. No isolation was made from unexposed control groups. The result indicates that the isolate is highly virulent for both chickens and mice.

Keywords : fowl cholera, Pasteurella multocida, virulence, chickens, mice

Date: 2004 l  Full Text

Summary : A rapid and simple technique for diagnosis of rotaviral diarrhea is polyacrylamide gel electrophoresis (PAGE) of dsRNA extracted from fecal samples. To determine the electrophoretype of Iranian calf rotavirus, 23 rotaviral positive fecal samples from diarrheic Holstein calves at the age of less than one month in Tehran region were examined. The viral dsRNA was extracted with phenol-chloroform, and analyzed by PAGE and silver staining. According to PAGE all of the electrophoretypes were identified as long genome electrophoretypes, characteristic of animal group A rotavirus. There was not any unusual segment rearrangement.

Keywords : rotavirus, electrophoretype, PAGE, diarrhea, calf

Date: 2004 l  Full Text

Summary : The differential activation of Th1 and Th2 cells using mafosfamide (Mafo) was investigated in vitro in a rat model of alloreactivity. The results of this study are compatible with the hypothesis that Mafo, like its parent compound cyclophosphamide, is selectively active against Th2-type T-helper cells when administered at low doses (<0.1?M). Mafo suppressed the activation of suppressor cells and increased cytotoxicity and proliferation of CD4 rather than CD8 T-cells. Interestingly, treatment with Mafo reversed the inhibitory effect of cAMP on lymph node cell proliferation. It seems to interfere with second messenger signalling pathways, through interactions in a subtle way with the cAMP-dependent protein kinase system. Therefore, Mafo can open up new possibilities for examination in the colonogenic cell assay, in vitro, and also for the regional therapy of allergy, specifically for low doses of Mafo, as an immunomodulator.

Keywords : mafosfamide, cyclophosphamide, immunomodulation, T-cell

Date: 2004 l  Full Text

Summary : A purification procedure of pertussis toxin (PT) from submerged culture of Bordetella pertussis (B.pertussis) strain 134 using adsorption and affinity chromatography was discussed. The yield of the resulting PT was approximately 37.5mg/l of concentrated culture supernatant. The polypeptide pattern of the purified PT was investigated by SDS-PAGE and showed five bands between 11 to 26 KDa using low molecular weight marker. Since PT is the main component of acellular pertussis vaccine, obtaining a good yield of it would be essential for production of the new and safer vaccine generation. The other objective of this study was to determine the effects of PT on murine lymphocytes using MTT test. The effect of various doses of prepared PT on murine lymphocytes showed that the amount of 0.5µg/0.1ml had the highest proliferation. Furthermore comparison between the resulting PT and phytohemagglutinin showed much higher effect of PT on murine spleen cells. These results indicate that B.pertussis strain 134 is a suitable strain for induction of PT in order to use it for development of acellular vaccine in Iran and also for in vitro studies on proliferation of murine lymphocytes.

Keywords : pertussis toxin, purification, lymphocyte proliferation, spleen cell

Date: 2004 l  Full Text

Summary : The type, severity and frequency of gross lesion, histopatholgic change, and tissue tropism of A/Chicken/Iran/259/1998(H9N2) avian influenza virus following intratrachealy (IT) inoculation were studied in chickens. Twenty, 5-week-old chickens (hatched from SPF eggs) were inoculated with this virus. Another twenty chickens were inoculated with sterile chorio allantoic fluid. Tracheitis, pneumonia and tubulointerstital nephritis were the most frequent specific histopathologic changes. Influenza nucleoproteins were demonstrated in epithelium of trachea, secondary bronchi and cecal tonsile of an inoculated chicken. Common non-specific histopathologic changes were lymphoid and reticuloendothelial cell hyperplasia in spleen, cecal tonsil and leukocyte cell infiltration in myocardium. These results indicate that the low-pathogenic avian influenza virus is epithliotropic in chicken. In IT route of inoculation, it has tissue tropism and pathogenicity for trachea, lung (pneumotropic) and kidney (nephrotropic).

Keywords : influenza virus, low-pathogenic, intratracheal, histopathology, chicken

Date: 2004 l  Full Text

Summary : 53 persons suspected to alpha1-antitrypsin deficiency detection (AATD) were investigated for ZZ, MZ, ZS, SS, and MS alleles analysis by serum protein electrophoresis (SPE), measurement of trypsin inhibiting capacity (TIC), isoelectric focusing (IEF), polymerase chain reaction (PCR), and IEF/PCR-RFLP techniques. The result clearly shows by using SPE and TIC techniques only 35.85 % and 50.08% of AATD cases can detect respectively while, IEF/PCR-RFLP joined technique can detect 100% of AATD cases. However, since IEF/PCR-RFLP joined technique can determine the protein structure and alleles gene mutation together, they can detect up to 100% of AAT. Hence for detection of AATD the IEF/PCR-RFLP technique is recommended.

Keywords : isoelectric focusing, ai-antitrypsin, ai-antitrypsin deficiency, alleles, PCR-RFLP

Date: 2004 l  Full Text

Summary : To isolate and detect anthrax spores from soil in different regions of Isfahan, Iran a total of 60 environmental specimens were collected during 2003. Bacterial endospores were extracted via flotation in distilled water and were cultured on blood agar and selective PLET media. Bacillus anthracis was identified using bacteriological and biological tests. Viable Bacillus anthracis spores were isolated from 9 (15%) soil samples of the 60 collected specimens in which 6 (66%) of isolates were encapsulated. The isolated bacteria and their virulence were confirmed with polymerase chain reaction (PCR) using specific primers. Its recommend that because of the existence of highly virulent strain of Bacillus anthracis in this region, a review on implementation of control programs such as regular vaccination of all susceptible livestock and surveillance of the disease in animals and human in such endemic areas is required.

Keywords : Bacillus anthracis, anthrax, soil, Iran

Date: 2004 l  Full Text

Summary : To carry out the immunological experiments on the serum of Multiple Sclerosis (MS) patients, based on a correlation between Borrelia burgdorferi infection and contracting MS autoimmune disease the outer surface protein D (OspD) of the bacterium was expressed and purified. A clone containing the OspD gene in pET11a expression vector under the control of T7 promoter was transformed to the bacterial host BL21 (DE3). Some of the colonies were selected for IPTG-induced expression. The colony with the highest amount of OspD was selected for large-scale expression. Large-scale protein purification was performed by the reversed phase HPLC with a C4 preparative column; ultimately, the expressed purified protein was confirmed by the Western blot technique.

Keywords : Borrelia burgdorferi, OspD, expression, purification, HPLC

Date: 2004 l  Full Text

Summary : The pathogenicity of a recent isolate of Infectious bursal disease virus (IBDV), IR499, isolated from a nonvaccinated flock with 17.5 % mortality rate in susceptible SPF chickens, chickens embryos and broilers was discussed. The molecular characterization of the virus based on the restriction fragment length polymorphism (RFLP) pattern was also investigated. The mortality rates were 85% and 22% in SPF and broiler chickens, respectively. The bursal weight indexes were 4.7 and 1.2 for SPF birds and 1.7 and 0.7 for susceptible broilers four and nine days post inoculation, respectively. The gross lesions were generalized including moderate to sever bursal hemorrhage. Using RT-PCR, a 643bp PCR product was amplified then nested PCR was carried out to amplify a 552bp PCR product. The 552bp product was subjected to SspI, StuI, HhaI and SacI restriction enzymes digestion which was SspI and StuI double positive and HhaI and SacI double negative. The pathogenicity and RFLP pattern finding confirmed that the IR499 virus could be classified as a very virulent IBDV.

Keywords : Infectious bursal disease virus, pathogenicity, RT-PCR, RFLP, very virulent

Date: 2004 l  Full Text

Summary : ?1320 blood samples were collected from herds showing clinical signs of pestiviral infections. 39 samples were positive in Ag-ELISA assay. All these 39 samples in addition to 5 cytopathic strains were cultured in MD-BK cell line and presence of pestiviral antigens was confirmed by direct-immunofluorescent test. 27 out of 44 BVDV suspected isolates were detected by RT-PCR using a primer set. Differentiation among the viruses was achieved by cutting the PCR products with restriction endonucleses enzymes Ava1, Bgl1 and Alu1. Using this procedure it was possible to distinguish at least two genogroups, 1 and 2 BDV containing 14 and 3 isolates, respectively.

Keywords : Bovine viral diarrhea, RT-PCR, RFLP, genotyping