conclusions although the frequency of hbsag seropositivity in the present study was close to that observed in the overall iranian population, the seroprevalence of anti-hbc was higher, possibly due to the exposure of the elderly to more risk factors. the risk factors were similar. these included a history of blood transfusions, cupping, hospital admission, endoscopy, or familial hbv/hcv infecti...

the genome of hb v virus of serotype ayw cloned in pbr322 and expression shuttle vector p yes2 were used for construction of the hbsag chimeric genes and their expression in saccharomyces cerevisiae. two recombinant plasmids were constructed. one of them contained the coding sequences for the major polypeptide of surface antigen. another construct carried the major polypeptide with the pre-s2 a...

RNA challenge phages are derivatives of bacteriophage P22 that enable direct genetic selection for a specific RNA-protein interaction. The bacteriophage P22 R17 encodes a wild-type R17 operator site and undergoes lysogenic development following infection of susceptible bacterial strains that express the R17/MS2 coat protein. A P22 R17 derivative with an OcRNA site (P22 R17 [A(-10)U]) develops l...

The temperate Salmonella enterica bacteriophage L is a close relative of the very well studied bacteriophage P22. In this study we show that the L procapsid assembly and DNA packaging genes, which encode terminase, portal, scaffold, and coat proteins, are extremely close relatives of the homologous P22 genes (96.3 to 99.1% identity in encoded amino acid sequence). However, we also identify an L...

background the transmission of hepatitis b virus (hbv) is parenteral, sexual and prenatal. prevention of vertical transmission of hbv is extremely important, because hbv infection in early life usually results in a chronic carrier state. there has been so much debate about hepatitis b surface antigen (hbsag) screening in pregnant women. objectives the aim of this study was to determine the prev...

we measured the prevalence of hbv surface antigen (hbsag) among male injection drug users (idus) in detention, tehran, iran. a cross-sectional survey included 499 male idus arrested by police during a predetermined police sweep in tehran (february, 2006). a questionnaire was filled out for each individual. blood specimens were collected for hbsag testing. prevalence of hbsag was 5.8% (95% ci 3....

Toxoplasma gondii (T gondii) is a common parasite that shows affinity to neural tissue and may lead the formation of cysts in brain. Previous epidemiologic studies have suggested an association between glioma increased prevalence T infection, but prospective are lacking. Therefore, we examined prediagnostic antibodies risk two cohorts using nested case-control study design. Cases matched contro...

the emergence of plasmodium vivax in dashte moghan in northwestern iran has become a major concern for iranian's health officials. knowledge of genetic make up of the p. vivax populations in this area would give us an insight into the origin of the prevalent infections and the possible routes they are introduced. this paper reports the analysis of a variable region between the two interspecies ...

conclusions in comparison with the rate of hbcab positivity reported in other iranian studies, the rate was higher in the present study. there were a few variations, genotypes, and subtypes among the infected injecting drug users. further investigations are needed to unravel the molecular characterization of obi. results sixty-four (28%) participants were hbcab positive, 59 cases were hbcab pos...

TSPs (tailspike proteins) are essential infection organelles of bacteriophage P22. Upon infection, P22TSP binds to and cleaves the O-antigen moiety of the LPS (lipopolysaccharide) of its Salmonella host. To elucidate the role of TSP during infection, we have studied binding to oligosaccharides and polysaccharides of Salmonella enterica Typhimurium and Enteritidis in vitro. P22TSP is a trimeric ...