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Background and Objective: The Clostridium botulinum is one of the most important causative of food poisoning. Spores of Clostridium botulinum spread out in the soil, the sea sediments, the marine environments and the marine animals. In recent years use of the marine food products like as fish and cultured fish are elevated. The aim of this study was done to compare between processing and non processing fish infected by predominant type of Clostridium botulinum.

Materials and Methods: This descriptive study was done on the 146 samples of fish in two species of processed and non prosecced that collected from Gilan province in Iran during 2008. These samples included the Liza auratus Fish (45 processed fish and 28 non processed fish) and the Salmo Trutta caspius Fish (34 processing fish and 39 non processing fish). The samples examined according to the APHA2000 and FDA2003 protocols. Data Analyzed with SPSS-13 and Chi-Square test.

Results: 16 (11%) of samples (13% of the processed fish and 7.5% of non processed fish) were confirmed that infected by Clostridium botulinum. Also the dominant type of exotoxin was Type E. The Type E exotoxin was determined from 11 of the samples (6 processed fish and 5 non processed fish).

Conclusion: This study showed that fish are infected by Clostridium botulinum special the type E. also use of fish in bad preparation (half cooking and add material in its stomach) may cause the food poisoning.

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Background and Objective: Considering the significant incidence of nosocomial infections in hospitalized patients, this study was done to determine the prevalence of Staphylococcus aureus strains isolated from wound infection and drug sensitivity pattern, Tehran-Iran. Materials and Methods: In this descriptive study, Staphylococcus aureus isolated and identified according to standard procedures from the wound infections of 614 patients referred to Baqiyatallah hospital, Tehran-Iran during 2006-07. The samples were examined and antibiogram was performed by disc diffusion method on Mueller Hinton agar with 12 antibiotics. Results: 100 (16.28%) of wound infection of Staphylococcus aureus was isolated from 614 patients. The infection rate in men was twice compared to women. The highest rate 29 (29%) was observed in people aged 40 to 60 group. Also specimen's patients with immunosuppressive diseases (28 cases), surgical site infection (16 cases) and normal wounds (13 cases) were considered to be most prevalent isolates. Antibiotic sensitivity testing revealed that 96 (96%) of isolates were sensitive to vancomycin, 95 (95%) and 92 (92%) were resistant to penicillin and cotrimoxazole, respectively. Our result showed that 43% of strains were resistant at 11 antibiotics. Conclusion: This study showed that the prevalence of Staphylococcus aureus was 16.28% of samples, with 43% antibiotic resistance. The highest sensitivity was toward to vancomycin.

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Background and Objective: Bacterial resistance to Imipenem is increased in bacterial infections in Iran. In regard to the importance of Imipenem in the treatment of nosocomial infections and the key role of disc diffusion method as a major antibiotic susceptibility testing assay, this study was done to determine the prevalency of imipenem-resistant bacterial strains isolated from hospital and accuracy of Iranian imipenem disc product. Methods: In this descriptive-analytic study, 241 bacteria were isolated from patients in different wards of the Baqyatallah hospital in Tehran, Iran during 2013-14. After streaking of the organisms, identification was performed by all conventional biochemical tests. The bacterial resistance to imipenem was determined by disk diffusion method using Iranian and Mast imipenem discs. True imipenem-resistant isolates were examined for susceptibility to six different antibiotic including Ciprofloxacin, Gentamicin, Cephalexin, Azitromysin, Tetracycline and Ceftazidim, using disk diffusion method. Results: The most prevalent isolates organisms were gram-negative bacilli (Klebsiella, Escherichia coli, and Pseudomonas aeruginosa, respectively). The common clinical source was urine and wound samples, respectively. Resistant to Imipenem was 68 (25.7 %) and 19 (7.8 %) based on the results of Iranian and Mast Imipenem discs, respectively. False results for Iranian Imipenem discs was higher than Mast Imipenem discs (P<0.05). Among the 19 true Imipenem resistant isolates, 17 micro organisms were Pseudomonas aeruginosa. 57% of isolated resistant to Imipenem were isolated from ICU ward. The most resistance was seen to Gentamicin (84%) and the lowest was seen to Ciprofloxacin (63%). 84% of isolated samples were multi drug resistance. Conclusion: Although a small percentage of the isolates obtained as important nosocomial pathogens were resistant to Imipenem, but the rate of multiple resistance and high rate of isolates obtained from ICU was noticeable.

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Background and Objective: Enterotoxigenic Escherichia coli (ETEC) are the most common agent which causes diarrhea, worldwide. ETEC is colonized along the cells and then producing heat-labile (LT) and heat-stable enterotoxigenic which enter into intestinal epithelial cells and causes water and electrolyte loss from intestinal epithelial cells and eventually cause diarrhea.This study was done to detect the heat-labile toxin in Enterotoxigenic Escherichia coli using PCR-ELISA technique. Methods: In this descriptive study, DIG-labeled PCR products were bounded to streptoavidin-coated wells of a microtiter plate and detected by anti-DIG–peroxidase conjugate. The biotin-labeled internal probe was used for verification of PCR products. Results: Heat-labile toxin was detected by PCR-ELISA method. The sensitivity of heat-labile toxin was 1.9 ng. This method did not cross-react with bacteria from this variety. Conclusion: PCR-ELISA method is 100 times more sensitive than conventional PCR method and due to lack of agarose gel and electrophoresis device it can be a good alternative to traditional method.

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Background and Objective: Wound infection treatment, particularly in chronic and bacterial poly cases, is difficult and entails heavy costs. This study was done to determine the prevalence of poly bacterial infection and antimicrobial susceptibility of wound samples from different wards. Methods: In this descriptive study, wound sampling was prepared from 336 patients admitted to different wards of Baqiatallah Hospital in Tehran, Iran. Identification was performed based on biochemical tests including oxidase test, TSI, IMVIC, lysine decarboxylase, phenylalanine deaminase, urea, motility, catalase, coagulase, mannitol fermentation, optochin sensitivity, susceptibility to bacitracin and sulfamethoxazole, growth in Bile esculin and DNase production. Antibiotic resistance pattern of isolates was determined using disk diffusion method for 14 important antibiotics. Results: 294 samples were positive for bacterial culture, from which 364 isolates including 11 different isolates were obtained. Out of 294 positive samples, 245 samples were mono bacterial and 54 were poly bacterial including two-bacterial (45 samples), three-bacterial (7 samples), and four-bacteral (2 samples). S. aureus (29.7%), Enterococci (15.6%), and E. coli (15.6%) were the most prevalent isolates. S. aureus-Enterococci pattern was the most common two-bacterial pattern (33%), and majority of polybacterial patterns belonging to gram negative bacteria was in surgery ward (32.5%). Antibiogram results showed high levels of antibiotic resistance in the isolates. Imipenem and amikacin were the most effective antibiotics against Gram negative isolates, and vancomycin for Gram positive isolates. Also, 71% of S. aureus isolates were resistant to oxacillin. Conclusion: Variation of bacterial isolates was similar to other studies. Most of poly-bacterial wound infections were due to common nosocomial pathogens and their high rates of antibiotic resistance are extremely alarming.