Factors associated with self-reported hepatitis B virus vaccination status among men who have sex with men in the Netherlands.

Background Reducing the number of new acute hepatitis B virus (HBV) infections to zero by 2022 is an important goal in the Netherlands. Free HBV vaccination is available for population groups at higher risk of infection, including men who have sex with men (MSM). Identifying correlates of HBV vaccination among MSM can guide the development of health promotion interventions to increase coverage of HBV vaccination. METHODS: We assessed factors associated with the HBV vaccination status of 4270 MSM in the Netherlands. Data were collected through the 2018 online Men & Sexuality survey. RESULTS: Multinomial regression analysis showed that lower education level, having never tested for HIV, not recently diagnosed with a sexually transmissible infection, recently having had sex abroad and unknown HBV testing status were associated with higher odds of being unvaccinated as opposed to fully vaccinated. Living in Amsterdam and testing HBV negative were associated with lower odds of being unvaccinated as opposed to fully vaccinated. Age (25-39 years vs younger ages), living in Amsterdam and using pre-exposure prophylaxis decreased the odds to be partly vaccinated as opposed to fully vaccinated; having a migration background increased these odds. CONCLUSIONS: HBV vaccination rates among MSM will not reduce HBV transmission to zero. HBV promotion should focus on MSM outside of Amsterdam who are likely less connected with sexual health services and may be at lower (perceived) risk. The factors identified related to HBV vaccination status provide guidance for health promotion interventions to increase uptake and vaccination completion among MSM.

A serological divide: men who have sex with men's attitudes on HIV risk reduction strategies.

The expanding HIV risk reduction toolkit increases options for men who have sex men (MSM), but increasing options in combination with different preferences may complicate promoting risk reduction. To investigate what strategies MSM prefer, data of 3310 participants in the online survey "Men & Sexuality" (Median age = 37 years, 320 (9.7%) HIV positive) was analysed. Questions assessed attitudes towards HIV risk reduction strategies. Participants had the most positive attitudes regarding PrEP and HIV testing, while withdrawal and strategic positioning were least preferred (all p's < .001). Condoms were seen as acceptable to partners and effective but scored low on sexual pleasure. HIV-positive participants were more negative about condoms and more positive about viral load sorting than HIV-negative participants (F(12,3297) = 5.09, p < .001, [Formula: see text] = .02). Findings highlight a preference for HIV risk reduction strategies (PrEP and HIV testing) that do not diminish sexual pleasure and can be applied independent of sexual partners. A serological divide was apparent: HIV-negative MSM were less negative about condoms than HIV-positive MSM, suggesting that condom promotion remains a viable strategy for HIV-negative MSM. Taken together, results indicate a need for personalized approaches to the promotion of HIV risk reduction strategies, accounting for individual preferences and strategy effectiveness.

A meta-analysis of overall effects of weight loss interventions delivered via mobile phones and effect size differences according to delivery mode, personal contact, and intervention intensity and duration.

Weight loss interventions are delivered through various mediums including, increasingly, mobile phones. This systematic review and meta-analysis assesses whether interventions delivered via mobile phones reduce body weight and which intervention characteristics are associated with efficacy. The study included randomised controlled trials assessing the efficacy of weight loss interventions delivered via mobile phones. A meta-analysis to test intervention efficacy was performed, and subgroup analyses were conducted to determine whether interventions' delivery mode(s), inclusion of personal contact, duration and interaction frequency improve efficacy. Pooled body weight reduction (d = -0.23; 95% confidence interval = -0.38, -0.08) was significant. Interventions delivered via other modes in addition to the mobile phone were associated with weight reduction. Personal contact and more frequent interactions in interventions were also associated with greater weight reduction. In conclusion, the current body of evidence shows that interventions delivered via mobile phones produce a modest reduction in body weight when combined with other delivery modes. Delivering interventions with frequent and personal interactions may in particular benefit weight loss results.

The WASP homologue Las17 activates the novel actin-regulatory activity of Ysc84 to promote endocytosis in yeast.

Actin plays an essential role in many eukaryotic cellular processes, including motility, generation of polarity, and membrane trafficking. Actin function in these roles is regulated by association with proteins that affect its polymerization state, dynamics, and organization. Numerous proteins have been shown to localize with cortical patches of yeast actin during endocytosis, but the role of many of these proteins remains poorly understood. Here, we reveal that the yeast protein Ysc84 represents a new class of actin-binding proteins, conserved from yeast to humans. It contains a novel N-terminal actin-binding domain termed Ysc84 actin binding (YAB), which can bind and bundle actin filaments. Intriguingly, full-length Ysc84 alone does not bind to actin, but binding can be activated by a specific motif within the polyproline region of the yeast WASP homologue Las17. We also identify a new monomeric actin-binding site on Las17. Together, the polyproline region of Las17 and Ysc84 can promote actin polymerization. Using live cell imaging, kinetics of assembly and disassembly of proteins at the endocytic site were analyzed and reveal that loss of Ysc84 and its homologue Lsb3 decrease inward movement of vesicles consistent with a role in actin polymerization during endocytosis.

Balancing risk and pleasure: sexual self-control as a moderator of the influence of sexual desires on sexual risk-taking in men who have sex with men.

OBJECTIVES: To assess the extent to which sexual risk-taking among men who have sex with men (MSM) is influenced by their sexual desires, as reflected in sexual sensation seeking, and to establish whether men's sexual self-control moderates the influence of sexual sensation seeking. METHODS: An online survey in the Netherlands recruited 1613 MSM; 1129 men who had sex with casual partners and reported full data were included in this study. Potential sexual risk-taking in the preceding 12 months was indexed by number of casual partners (<10 vs > or =10), unprotected anal intercourse with casual partners (UAI-C; no vs yes) and sexually transmitted infections (no vs yes). RESULTS: Potential sexual risk-taking with casual partners was highly prevalent in this online sample of MSM; 51.0% had 10 or more casual sex partners, 38.8% had engaged in UAI-C and 22.9% reported having had a sexually transmitted disease. Multivariate logistic regression analyses showed that sexual sensation seeking was significantly related to more risk-taking according to each outcome variable, while all effects of sexual self-control were significantly protective. As expected, sexual self-control attenuated the effects of high sexual sensation seeking on UAI-C, but not on numbers of partners and infection with a sexually transmitted infection. CONCLUSIONS: Although MSM who are higher in sexual sensation seeking are more likely to engage in sexual risk-taking, some men successfully self-regulate the influence of their sexual desires on UAI-C. While men high in sexual self-control may spontaneously control their sexual desires, men low in sexual self-control may benefit from a generation of prevention tools that promote planning ahead of time.

To test or not to test: psychosocial barriers to HIV testing in high-income countries.

To contribute to the evidence-based understanding of the psychosocial factors that influence individuals' uptake of testing for HIV, we assessed and synthesized the pertinent published literature in the fields of public health, behavioural medicine, and (health) psychology. Although the evidence base appears too limited to allow firm conclusions and definition on psychological barriers to HIV testing in high-income countries, we identified convergent themes from the available studies. Testing for HIV seems to be more likely when individuals perceive that they have been at risk, though this association is not perfectly observed. Fear of the consequences of testing positive -mainly worries related to discrimination and rejection - also hinders HIV testing. Finally, individuals appear more likely to test for HIV when they perceive more benefits from testing. The perspective of targeted individuals, in particular the social connotations and consequences of HIV diagnoses, is crucial to understand testing decisions.