Distribution of Hepatitis C virus genotypes in city of Mashhad, North-east of Iran.

PURPOSE: Six major hepatitis C virus genotypes have been characterised, which vary in their geographical distribution. The prevalence of hepatitis C virus (HCV) in an area is not constant, and depends on the changes in route of infection, which may change over time. In this study, the distribution of HCV genotypes in Mashhad, the capital of Razavi Khorasan province in north-east of Iran was investigated. Mashhad is a holy city of Shiate Moslems, which attracts more than 20 million tourists and pilgrims every year. MATERIALS AND METHODS: Two hundred and seventy-eight HCV infected subjects (227 males and 51 females) were included in this study. HCV genotypes were analysed by type specific reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: Genotype 3a was detected in 49.6%, 1a in 36.3%, 1b in 12.6% and 2a in 0.4%. Two HCV genotypes were detected in 1.1% cases; 1a +3a in 1%, 3a + 1b in 0.4%. Genotypes 2b and 3b were not detected in any samples. CONCLUSION: We demonstrated that despite the previous reports on the frequency of HCV genotypes in Iran, 3a is the predominant genotype in Mashhad.

Immunotoxicity of paraquat after subacute exposure to mice.

The immunotoxic effect of paraquat (PQ), a herbicide that has been used widely in agriculture was investigated using Balb/c mice. Paraquat was administered at doses of 1, 0.1, and 0.01 mg/kg for 21 days. Body weight, organ weight, cellularity of spleen, delayed type of hypersensitivity (DTH) response, plaque-forming cell (PFC) assay, hemagglutination titer (HA), quantitative hemolysis of SRBC (QHS) assay, spleen cell subtypes, cytokine production and lymphocyte proliferation assay were studied in various groups of animals. Results showed that high dose of PQ (1mg/kg) could suppress both cellular and humoral activity of the immune system. PQ at medium dose (0.1 mg/kg) did not show any changes in organ weight, body weight and spleen cellularity but significantly decreased the proliferation response to PHA and the production of IFNgamma. PQ at low dose (0.01 mg/kg) did not produce any significant changes in humoral or cellular responses of the immune system. In conclusion, paraquat at high dose has an inhibitory effect on the cell-mediated and humoral immunity. It seems that PQ has no adverse effects on mice immune system at low doses of 0.01 mg/kg, which is two times the PQ allowed daily intake (ADI) limit.