Trends in HIV prevalence and risk behaviours among men who have sex with men from 2013 to 2017 in Nanjing, China: a consecutive cross-sectional survey.

OBJECTIVE:To examine the trends of HIV prevalence, risk behaviours and HIV testing among men who have sex with men (MSM) in Nanjing. DESIGN:Five consecutive cross-sectional surveys. SETTING:Nanjing, China. PRIMARY AND SECONDARY OUTCOME MEASURES:HIV and syphilis prevalence, HIV testing rate and factors associated with HIV infection; demographic characteristics and behaviours. RESULTS:649, 669, 577, 633, 503 MSM were recruited from 2013 to 2017. HIV prevalence was 9.9%, 12.3%, 12.5%, 9.8% and 10.1%, respectively. Syphilis prevalence decreased with a range from 10.6% to 5.6%. Risk behaviours like unprotected anal intercourse (UAI) and unprotected virginal sex in the past 6 months decreased, but multiple sex partners and ever used rush popper rose significantly. MSM tested for HIV in the previous year remained stable from 57.0% to 64.1% (P=0.633). Multivariate analysis showed that tested for HIV in the past year was protective factor against HIV infection. MSM who had UAI in the past 6 months, sex role as receptive and dual, diagnosed with sexually transmitted diseases (STDs) in the past year and currently syphilis infected were risk factors for HIV infection. CONCLUSIONS:We observed stable high HIV prevalence, a steady HIV testing rate, decreasing syphilis prevalence and UAI among MSM in Nanjing. However, rush popper use rose dramatically. The HIV preventive strategies for MSM including condom promotion, HIV testing expansion and reduction of rush popper use, STDs screening and standardised treatment should be strengthened

Hypoxia-inducible transcription factor-1α promotes hypoxia-induced A549 apoptosis via a mechanism that involves the glycolysis pathway

BACKGROUND: Hypoxia-inducible transcription factor-1α (HIF-1α), which plays an important role in controlling the hypoxia-induced glycolysis pathway, is a "master" gene in the tissue hypoxia response during tumor development. However, its role in the apoptosis of non-small cell lung cancer remains unknown. Here, we have studied the effects of HIF-1α on apoptosis by modulating HIF-1α gene expression in A549 cells through both siRNA knock-down and over-expression. METHODS: A549 cells were transfected with a HIF-1α siRNA plasmid or a HIF-1α expression vector. Transfected cells were exposed to a normoxic or hypoxic environment in the presence or absence of 25 mM HEPES and 2-deoxyglucose (2-DG) (5 mM). The expression of three key genes of the glycolysis pathway, glucose transporter type 1(GLUT1), phosphoglycerate kinase 1(PGK1), and hexokinase 1(HK1), were measured using real-time RT-PCR. Glycolysis was monitored by measuring changes of pH and lactate concentration in the culture medium. Apoptosis was detected by TUNEL assay and flow cytometry. RESULTS: Knocking down expression of HIF-1α inhibited the glycolysis pathway, increased the pH of the culture medium, and protected the cells from hypoxia-induced apoptosis. In contrast, over-expression of HIF-1α accelerated glycolysis in A549 cells, decreased the pH of the culture medium, and enhanced hypoxia-induced apoptosis. These effects of HIF-1α on glycolysis, pH of the medium, and apoptosis were reversed by treatment with the glycolytic inhibitor, 2-DG. Apoptosis induced by HIF-1α over-expression was partially inhibited by increasing the buffering capacity of the culture medium by adding HEPES. CONCLUSION: During hypoxia in A549 cells, HIF-1α promotes activity of the glycolysis pathway and decreases the pH of the culture medium, resulting in increased cellular apoptosis

Higher-order assembly of crystalline cylindrical micelles into membrane-extendable colloidosomes

Functional nanoscale objects can be prepared via crystallization-driven self-assembly of diblock copolymers. Here the authors show the self-assembly of crystalline block copolymers into size-specific cylindrical micelles for the hierarchical construction of mechanically robust colloidosomes with a range of membrane textures

Characterization and structural basis of a lethal mouse-adapted SARS-CoV-2.

There is an urgent need for animal models to study SARS-CoV-2 pathogenicity. Here, we generate and characterize a novel mouse-adapted SARS-CoV-2 strain, MASCp36, that causes severe respiratory symptoms, and mortality. Our model exhibits age- and gender-related mortality akin to severe COVID-19. Deep sequencing identified three amino acid substitutions, N501Y, Q493H, and K417N, at the receptor binding domain (RBD) of MASCp36, during in vivo passaging. All three RBD mutations significantly enhance binding affinity to its endogenous receptor, ACE2. Cryo-electron microscopy analysis of human ACE2 (hACE2), or mouse ACE2 (mACE2), in complex with the RBD of MASCp36, at 3.1 to 3.7 Å resolution, reveals the molecular basis for the receptor-binding switch. N501Y and Q493H enhance the binding affinity to hACE2, whereas triple mutations at N501Y/Q493H/K417N decrease affinity and reduce infectivity of MASCp36. Our study provides a platform for studying SARS-CoV-2 pathogenesis, and unveils the molecular mechanism for its rapid adaptation and evolution

Which user errors matter during HIV self-testing? A qualitative participant observation study of men who have sex with men (MSM) in China

Abstract Background The World Health Organization recommends HIV self-testing (HIVST) as an additional approach to HIV testing services. We aimed to assess to what extent HIVST was conducted correctly by Chinese men who have sex with men (MSM) and to identify user errors during the HIVST process in order to inform strategies to optimize its use and thus reduce the number of undiagnosed HIV infections. Methods Between February and March 2017, participant observations were conducted with 27 MSM in an east coastal city in China. In the presence, but without the assistance or orientation, of a trained HIV testing counselor, participants conducted HIVST (either finger prick or oral fluid) according to manufacturers’ instructions. Errors were recorded on checklists during direct observation and double checked afterwards by reviewing video files of the observations. Results Overall, 12 participants (44.4%) had invalid test results due to user errors. Just five (18.5%) did not make any errors during the entire HIVST process. Failure to follow all the steps based on manufactures’ instructions was a common problem for both finger prick and oral fluid self-testers. For finger prick users, most errors occurred during the stage of collecting the specimen. In contrast, oral fluid users made most errors during the stage of testing the collected specimen. Conclusions Although we found that user errors were common among MSM administering HIVST, this should not deter or discourage routine implementation and scale-up of HIVST as strategies can be implemented to facilitate the correct use of HIVST. Trial registration This study was a part of a clinical trial: ClinicalTrials.gov (#NCT02999243); Registration date: December 20, 2016

Which user errors matter during HIV self-testing? A qualitative participant observation study of men who have sex with men (MSM) in China.

BackgroundThe World Health Organization recommends HIV self-testing (HIVST) as an additional approach to HIV testing services. We aimed to assess to what extent HIVST was conducted correctly by Chinese men who have sex with men (MSM) and to identify user errors during the HIVST process in order to inform strategies to optimize its use and thus reduce the number of undiagnosed HIV infections.MethodsBetween February and March 2017, participant observations were conducted with 27 MSM in an east coastal city in China. In the presence, but without the assistance or orientation, of a trained HIV testing counselor, participants conducted HIVST (either finger prick or oral fluid) according to manufacturers' instructions. Errors were recorded on checklists during direct observation and double checked afterwards by reviewing video files of the observations.ResultsOverall, 12 participants (44.4%) had invalid test results due to user errors. Just five (18.5%) did not make any errors during the entire HIVST process. Failure to follow all the steps based on manufactures' instructions was a common problem for both finger prick and oral fluid self-testers. For finger prick users, most errors occurred during the stage of collecting the specimen. In contrast, oral fluid users made most errors during the stage of testing the collected specimen.ConclusionsAlthough we found that user errors were common among MSM administering HIVST, this should not deter or discourage routine implementation and scale-up of HIVST as strategies can be implemented to facilitate the correct use of HIVST.Trial registrationThis study was a part of a clinical trial: ClinicalTrials.gov (# NCT02999243 ); Registration date: December 20, 2016