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Backgrounds: Parvovirus B19 (B19V) infection is mainly manifested as erythema infectiosum in children. Primary B19V infection during pregnancy is accompanied by a 30% risk of fetal infection, especially in epidemic conditions. Given the important impact of parvovirus B19 infection on maternal and neonate health, this study assessed parvovirus B19 susceptibility among women of childbearing age in Mashhad, northeast Iran.
Materials & Methods: Serum samples were collected from 185 women aged 20-35 years living in Mashhad. Cluster sampling was performed in different health centers located in the city to cover the main city area. A commercial ELISA kit was used to measure IgG antibodies against B19V. This study was performed in accordance with the ethical standards mentioned in the declaration of Helsinki. Informed consent was taken from all participants. A questionnaire was filled by each participant. SPSS software Version 11.5 was used for statistical analyses.
Findings: Anti-B19 IgG was observed in about 31% of women. Seroprevalence of anti- B19 antibodies among different age groups (with 5-year intervals) was not significantly different (p=.839). Also, there was no significant difference among different city areas of Mashhad in terms of anti-B19 IgG seropositivity (.39, p>.05).
Conclusion: The prevalence of parvovirus B19 infection varies in different parts of the world. Comparing to other reports, the present study revealed a rather low immunity against parvovirus B19 among women in Mashhad. These findings highlight the potential risk of B19 infection in non-immune/susceptible mothers, which may lead to sever outcomes, especially during epidemics.

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Objective: microRNAs (miRNAs) are noncoding RNAs that function as key regulators of diverse biological activities such as cellular metabolism, cell proliferation and cell cycle regulation. Recent studies have indicated the high potential of these small molecules to control stem cell differentiation into desired cells. The aim of present study is to investigate the possible effect of let-7f on expression of hepatic nuclear factor 4 alpha (HNF4a) and some hepatic specific factors such as albumin (ALB), alpha fetoprotein (AFP), cytokeratin18 (CK18) and cytokeratin19 (CK19) in human adipose tissue derived stem cells (hADSCs). Methods: ADSCs were isolated from human adipose tissue using collagenase type I and were transduced by recombinant lentiviruses that contained human inhibitor let-7f and Scramble (negative control). Afterward, the expressions of HNF4a, ALB, AFP, CK18 and CK19 were evaluated by Real-time PCR at different time points. Results: Transduction efficiency of lentiviral vectors into ADSCs was more than 80% as judged by the expression of the GFP reporter gene. Real-time PCR analysis revealed that inhibition of let-7f in hADSCs resulted in significant up regulation of hepatic specific genes compared with the negative control. The expression level of HNF4a also increased in experimental cells at day 14, which supported the suppression of HNF4a expression by let-7f. Conclusion: The results of this study identified let-7f as a negative regulator of HNF4a expression in hADSCs and increased the expression of hepatocyte specific factors through silencing of let-7f. Therefore, suppression of let-7f could be a considerable tool for hepatic differentiation of hADSCs.