Hepatitis B virus surface antigen assembly function persists when entire transmembrane domains 1 and 3 are replaced by a heterologous transmembrane sequence

Native hepatitis B surface antigen (HBsAg) spontaneously assembles into 22-nm subviral particles. The particles are lipoprotein micelles, in which HBsAg is believed to span the lipid layer four times. The first two transmembrane domains, TM1 and TM2, are required for particle assembly. We have probed the requirements for particle assembly by replacing the entire first or third TM domain of HBsAg with the transmembrane domain of HIV gp41. We found that either TM domain of HBsAg could be replaced, resulting in HBsAg-gp41 chimeras that formed particles efficiently. HBsAg formed particles even when both TM1 and TM3 were replaced with the gp41 domain. The results indicate remarkable flexibility in HBsAg particle formation and provide a novel way to express heterologous membrane proteins that are anchored to a lipid surface by their own membrane-spanning domain. The membrane-proximal exposed region (MPER) of gp41 is an important target of broadly reactive neutralizing antibodies against HIV-1, and HBsAg-MPER particles may provide a good platform for future vaccine development.     

Impact of polycystic ovary syndrome on eating behavior,depression and health related quality of life: A cross-sectional study in Riyadh

Background & objectivesPolycystic ovary syndrome (PCOS) is the most common endocrinal disorder, and the greatest cause of infertility in women. Despite availability of individual data on impact of multiple endocrinal, reproductive and even metabolic factors in PCOS individuals, the data on the co-existence of BED and depression in PCOS patients with its relationship on the quality of life in Saudi Arabian females is not found. Hence this study is aimed to elucidate the implication of PCOS on eating behaviour, induction of depression and general health quality in Saudi Arabian population of Riyadh.Materials and methodsThis is a cross-sectional study carried out in multiple health facilities of Riyadh from January to March 2019. The study samples (494) were recruited by convenience sampling and administered validated questionnaire by trained research participants. The data obtained was analysed by binary logistic regression using SPSS-IBM 25.ResultsOf the total 494 women participated in the study, 23.48% (116) were PCOS individuals. The odds of developing abnormal health related quality of (HRQ) in patients with PCOS was significantly (P = 0.000, OR = 3.472) high when compared to non-PCOS participants. The odds of showing high binge eating disorder (BED, P = 0.007, OR = 2.856) and depression (P = 0.000, OR = 2.497) scores in PCOS participants were significantly more than patients who were not having PCOS. Out of the three parameters studied, abnormal health related quality of life possessed a higher influence of PCOS compared to depression and abnormal eating behavior.Interpretation & conclusionIn conclusion, the present study shows that women with PCOS are at a significant risk for depressive disorders, disorganized eating behavior and impaired quality of life. Therefore, necessary care and screening is required to minimize the impact of PCOS on already burdened individuals.