[Cytolethal distending toxin [CDT] produced by Campylobacter jejuni and Campylobacter coli isolated from chikens by tissue culture method in Isfahan]

Campylobacter jejuni is one of the most common bacterial cause of diarrheal disease in humans throughout the world. Contamination is mainly linked to the consumption of undercooked food products contaminated with Campylobacters. The most characterized toxin proposed is CDT, which has been detected in several Campylobacter species. With regard to the role of broiler chickens in transmission of campylobacter to human and the possible role of CDT in the pathogenesis of Campylobacter, detection of Campylobacter producing CDT is necessary. In this study 368 rectal swabs were collected from chikens. All the specimens were cultured on Skirrows and Blood agar and incubated in microaerophilic conditions at 42°C for 48-72 h. Hella cell was applied to detect CDT in C. jejuni and coil. Campylobacter strains were isolated from 114 [31%] of 368 chicken [101 C. jejuni and 13 C. coli]. Toxin production in C. jejuni and C. coil was 94% and 76.9% respectively. It seems that the majority of C. jejuni and C. coli produce CDT although C. jejuni produces a higher titer

Detection of icaAD gene and biofilm formation in staphylococcus aureus isolates from wound infections

Wound infections are a common cause of staphylococcal infections. An ability of S.aureus is to adhere and form biofilm on host surfaces. Biofilm is an exopolysaccharide, a slime matrix around multiple layers of cells and is mediated by expression of the icaADBC operon. The present study evaluated the biofilm forming capacity and the presence of icaAD gene among S.aureus isolated from wound infections. Slime production assay was performed by cultivation on Congo Red Agar plate. In addition, Quantitative biofilm formation determined by microtiter plate assay PCR method used for detection of icaAD gene. Fifty strains were identified, 54% of the isolates produced black colonies on CRA plate, 52% were positive biofilm forming, and all strains carried the icaAD gene. Regarding the ability of S.aureus to form biofilms helps the bacterium to survive hostile environments within the host, suggests that biofilm production is a risk factor for infection. It is important in rapid diagnosis and treatment biofilm forming strains, because biofilm formation may lead to increased antimicrobial resistance and create a significant impediment to wound healing

Isolation of Brucella abortus using PCR-RFLP analysis

Brucella transmission and epidemiology depend on infecting species and biovar. Therefore, exact identification of the Brucella is important to design correct control and treatment strategies. In this study, we examined presence of other Brucellae in Isfahan. One hundred twenty Brucella isolates were collected and genomic DNA was extracted from them. omp2a fragment of all isolates were amplified using a pair of specific primers and the PCR products were electrophoresed and stained with EtBr. These PCR products were then restricted using PstI restriction endonuclease. The PCR products of all isolates had the same size of 1100bp. The banding pattern of PCR-RFLP for all of the isolates were similar to banding pattern of the Brucella melitensis biotype 1 except for 5 samples that demonstrated banding pattern similar to B. abortus. Based on our results, it is clear that biotype 1 of the B. melitensis is not the only Brucella present in Isfahan and now B. abortus is also present in our area. These results are very important in planning for the control of the disease as well epide-miology and even treatment of the patients