[ frequency and antibiotic resistance of chromate tolerating microorganisms in Qom industrial wastewater]

Chromium is one of the major sources of environmental pollution and a potent occupational carcinogen. The hexavalent chromium compounds are more toxic than those of trivalent. Recent studies have suggested that reduction of Cr[VI] to its lower oxidation states and related free radical reactions play an important role in carcinogenic, genotoxic and immunotoxic effects in human and animals. This paper reports occurrence of chromium tolerant and antibiotic resistant organism of four industrial wastewaters including electroplating, textile, galvanization, and dye manufacturing in Qom. In this study 241 isolates including 23 gram positive coccus, 3 gram negative bacilli and 215 gram positive bacilli were obtained by using of LB Agar plus determined concentration of potassium chromate. A gram positive coccus, chromate reducing bacteria strain isolated from effluent of chromo plaiting could tolerate up to 760mM concentration in 34[degree]c and pH=7 within 24h and showed resistance to some antibiotics. Biochemical, physiological, morphological and 16SrRNA tests showed this bacteria belongs to staphylococcus arlettae strain R1-7A. The result indicates that the indigenous microbial isolates can be useful for hexavalent chromium detoxification of chromium contamination environment and reduction of its pathogenicity and carcinogenicity, on the other hand the control of these bacteria is important from the medical view

[ effect of zoledronic acid on BSP expression and methylation during osteoblastic differentation of mesenchymal stem cells]

Bone sialoprotein [BSP] is a specific marker of osteoblastic differentiation. In this research, the effect of Zoledronic Acid on BSP expression and methylation status during osteoblastic differentiation of mesenchymal stem cells [MSCs] was evaluated. In this experimental study, MSCs were isolated from human bone marrow. For osteogenic differentiation, hMSCs were pulse treated with zoledronic acid, and were incubated in osteogenic differentiation medium for 3 weeks. The DNA and RNA were extracted after the first, second and third weeks of culture and also from undifferentiated MSCs. After Sodium bisulfate [SBS] treatment, gene specific methylation analysis for BSP was carried out using Methylation Specific PCR technique. BSP expression was observed in osteoblastic differentiated cells whereas it was not seen in MSCs. MSP showed that BSP was unmethylated during osteoblastic differentiation. BSP was expressed from the first week of differentiation. This confirms that zoledronic acid accelerates osteoblastic differentiation. Unmethylation status of BSP indicates that zoledronic acid does not have any effect on BSP methylation status. Other genetic or epigenetic mechanisms may control BSP expression during osteoblastic differentiation induction by zoledronic acid

Medical interns' knowledge of tuberculosis and DOTS strategy in northern Islamic Republic of Iran

The increasing incidence of tuberculosis [TB] is a major concern to public health policy-makers. To assess knowledge about TB and the DOTS strategy among medical students in a high incidence area of the Islamic Republic of Iran, a questionnaire designed around the national TB programme guidelines was given to 80 interns in Golestan and Mazandaran medical schools in December 2007. The overall mean knowledge score was 1.80 [SD 1.61] items correct out of 15. Knowledge about diagnosis, treatment and monitoring was especially poor. There were no significant differences between the knowledge of interns who had completed their internships in the infectious diseases or community health departments compared with those who had not