ARCHIVES OF RAZI INSTITUTE
Year:1999 | Volume:- | Issue:50|Papers Count:10

A total number of 4138 sera from apparently healthy volunteers living in 8 different provinces of the western part of Iran were collected and tested by a standard ELISA. Of those, 3908 (94.45%) were negative and 230 (5.55%) were positive. The results are monitored according to ethnic groups, sex, age, occupation, training, province and season.      

The effect of levamisole on potency of enterotoxeima vaccine and also effect of the vaccine on anthelminthic activity of the drug were evaluated in naturally parastie infected sheep. 25 sheep were divided into 5 groups each of 5. The first group vaccinated with enterotoxemia alone, the second and third groups were injected subcutaneously with levamisole combined with vaccine and levamisole alone respectively. The two other groups were selected as control. Parasitology examination, was carried out by floatation technique and McMaster method while epsilon and beta antitoxins were detected in sheep sera by enzyme-linked immunosorbant assay and serum neutralization tests. Faecal egg per gram measurments and post-examination measurments showed no significantly differences between sheep injected with levamisole combined with vaccine and that received levamisole alone. Both groups were cured successfully with 100% efficacy. The results appeared that administration of levamisole in combination with enterotoxemia vaccine can effectively increase the serum epsilon antitoxin.  

A survey on camel brucellosis in Boushehr province of Iran was carried out during the year 1997. A total of 258 serum samples were collected and serologically examined. Out of these samples, 5 cases (%1.93) showed laboratory evidence of brucella infection. In bacteriological examination, the lymph nodes of all serologically positive camels were cultured. Brucella melitensis biotype 1 was isolated from two cultures.  

A total of twelve Newcastle disease virus isolates recovered from different outbreaks in Iran were analyzed for in vivo pathogenicity, biological property and amplification of F cleavage site gene. Intracerebral pathogenicity index varied from 1.7 to 1.96 while the intravenous pathogenicity index was more than 2.0. The mean death time value for all the isolates ranged from 39.6 to 68.8 hours. All the isolates except 2, hemagglutinated bovine erythrocytes whereas only one of the isolates agglutinated the equine erythrocytes. Polymerase chain reaction was used to amplify the F cleavage site gene of all isolates. Based on mean death time the Newcastle disease virus isolates could be placed in mesogenic or velogenic group.

To detect the cold agglutinin antibody in patients with Mycoplasma pneumoniae an investigation was carried out on the 135 pneumonic patient’s serum samples. The result indicated that there were 15 positive cases (11.1%) for M.pneumoniae antibody. Of these eleven positive cases (73.3%) for cold agglutinin with the titer of >1:16 showed anti-I specificity. It clearly demonstrated that M.pneumoniae was the major etiologic factor in cold agglutinin positive pneumonic cases. Competitive ELISA that reacted with 9G4 anti cross-reactive idiotype performed the frequency of crossreactive idiotype level in cold agglutinin antibody molecule. As compared to the normal value there was an increase mean value (50.8±24.2) in 15 patient’s serum samples. Hemagglutination inhibition test was performed on that 11 serum samples to investigate the relation between the cross- reactive idiotype positive serum and cold agglutinin antibody.

50 clinical Escherichia coli were isolated from 51 broiler farms in Urmia. An evaluation on antibacterial susceptibility testing of them against three selected fluoroquinolones was conducted. By using the Mast Diagnostics kit, the O1, O6, O15 and O55 serotypes were determined. For flumequine, enrofloxacin and norfloxacin the MIC values were 97.8, 12.6, and 24.4 μg/ml, respectively. Of the tested bacteria 8.6%, 34.6% and 24.4% were sensitive and 67.5%, 34.8% and 20.4% were resistant to flumequine, enrofloxacin and norfloxacin, respectively.

Lactase activity in presence of mono and divalent metal ions, as its cofactors, and some reducing agents was studied. Activation effects of k+ and Mn2+ were better than other cations and dithiotrethiol was more inhibitor. By inhibition constant, 12.15mMol, the type of inhibition was non-competitive. The kinetic model of Lactase hydrolysis reaction also was determined. Among glucose and galactose as its products, galactose had more inhibition effect and the type of inhibition was non-competitive. Galactose inhibition constant in lactose substrate was 78.7mMol.    

An indirect enzyme-linked immunosorbent assay (ELISA) was developed for the rapid and efficient large scale screening of antibodies to avian influenza virus (AIV) infection in chicken. Antigen was a whole-purified influenza virus produced from the H9N2 subtype. Optimum dilution for goat anti-chicken conjugate to be used in the ELISA was 1:1000, as determined by signal-to-noise ratio. The antigen concentration was 0.375μg of protein per well, as determined by checkerboard titration. The sensitivity of the ELISA was compared with hemmaglutination inhibition test under field exposure. After testing of 656 field sera, the correlation coefficient for the results of two tests was significant (r=0.929, P<0.001). Testing 8 standard antisera of various subtypes (H1, H2, H4, H5, H6, H7, H9 and H10) of AIV and AIV antibody positive and negative sera determined specificity of the ELISA. Antisera to all 8-hemmaglutinin subtypes were strongly positive. Both the sensitivity and specificity of the ELISA was compared to the other test. Thus, the ELISA was able to detect specific AIV antibodies and suitable for screening large numbers of samples in diagnostic laboratories.  

This survey was carried out via serum neutralization and ELISA tests with NADL strain of BVD virus. The sheep sera were collected from 8 different provinces of Iran. By SN test the rate of infection in all provinces was 13.5%. Chaharmahal-Bakhtiary and Khorasan showed highest (21.2%) and lowest rate (4.1%) rate of infection. By ELISA the total rate of infectivity came out to be 11.9% while by SN test using border disease virus (isolated from Iran) this rate was 12.8%. Statistical analysis revealed no significance differences in these results. According to the age, the lambs between 4-8 months showed lowest (8.1%) and those over 18 months had the highest (18.3%) infection rate.    

Out of 38 cases of malignant edema of cattle 19 Closteridium strains, Cl.septicum, Cl.chauvoei, Cl.novyi and Cl.perfringens were isolated during 1990-1992. Among isolated strains, three strains were Cl.septicum, four strains Cl.chauvoei, one strain Cl.novyi and eleven strains Cl.perfringens type A. Identification of strains was carried out by using fluorescent-labeled antibody technique. The hemolytic activity, toxicity and pathogenicity of the isolated strains were studied in this investigation.