MC3R links nutritional state to childhood growth and the timing of puberty.

The state of somatic energy stores in metazoans is communicated to the brain, which regulates key aspects of behaviour, growth, nutrient partitioning and development1. The central melanocortin system acts through melanocortin 4 receptor (MC4R) to control appetite, food intake and energy expenditure2. Here we present evidence that MC3R regulates the timing of sexual maturation, the rate of linear growth and the accrual of lean mass, which are all energy-sensitive processes. We found that humans who carry loss-of-function mutations in MC3R, including a rare homozygote individual, have a later onset of puberty. Consistent with previous findings in mice, they also had reduced linear growth, lean mass and circulating levels of IGF1. Mice lacking Mc3r had delayed sexual maturation and an insensitivity of reproductive cycle length to nutritional perturbation. The expression of Mc3r is enriched in hypothalamic neurons that control reproduction and growth, and expression increases during postnatal development in a manner that is consistent with a role in the regulation of sexual maturation. These findings suggest a bifurcating model of nutrient sensing by the central melanocortin pathway with signalling through MC4R controlling the acquisition and retention of calories, whereas signalling through MC3R primarily regulates the disposition of calories into growth, lean mass and the timing of sexual maturation.

Use of antiretroviral treatment among people living with HIV in Australia between 1997 and 2012.

Current international targets aim for 90% of people diagnosed with HIV to be on antiretroviral treatment (ART). This paper aims to identify sociodemographic and attitudinal factors associated with ART non-use over time in three samples of Australian people living with HIV (PLHIV). Data for this paper were derived from an Australian cross-sectional survey of PLHIV that was repeated at three different time points: 1997, 2003, and 2012. There were approximately 1000 respondents to each survey (n = 3042 in total). The survey included approximately 250 items related broadly to health and well-being, ART use, and attitudes towards ART use. Univariate and multivariate logistic regression analyses were used. While the proportion of participants using ART increased between 1997 and 2012 (78.8-87.6%, p < .001), there was a decrease between 1997 and 2003 to 70.6% (p < .001). Factors linked to ART non-use remained steady over those 15 years. In all cohorts, people less likely to be using ART were younger and had a more recent diagnosis of HIV. In 2003 and 2012, people in full-time employment were less likely to be using ART, while those whose main source of income was a pension or social security were more likely to be using ART. Multivariate models showed that, at each time point, a belief in the health benefits of delayed ART uptake was associated with non-use. These findings suggest that there may be barriers to ART uptake that have persisted over time despite changes to clinical guidelines that now encourage early uptake.

Is 'bareback' a useful construct in primary HIV-prevention? Definitions, identity and research.

The terms bareback and bareback identity are increasingly being used in academic discourse on HIV/AIDS without clear operationalization. Using in-depth, face-to-face interviews with an ethnically diverse sample of 120 HIV-infected and -uninfected men, mainly gay-identifying and recruited online in New York City, this study explored respondents' definitions of bareback sex, the role that intentionality and risk played in those definitions, and whether respondents identified as 'barebackers'. Results showed overall agreement with a basic definition of bareback sex as condomless anal intercourse, but considerable variation on other elements. Any identification as barebacker appeared too loose to be of use from a public health prevention perspective. To help focus HIV-prevention efforts, we propose a re-conceptualization that contextualises risky condomless anal intercourse and distinguishes between behaviours that are intentional and may result in HIV-primary transmission from those that are not.

The indeterminate macro-social: new traps for old players in HIV / AIDS social research.

PIP: The author discusses the first-ever study of male-to-male HIV-related sexual behavior in Fiji, Samoa, and Vanuatu, and the importance of sexual culture to HIV/AIDS education and research. The survey, based loosely upon Australian instruments, is attempting to document the HIV/AIDS knowledge, attitudes, social behaviors, and sex practices of homosexually active men to better target educational interventions for that population in the South Pacific. The research is being conducted by the AIDS Task Force of Fiji, a small nongovernmental organization, with help from the Australian government and UNAIDS. The researcher is informed by the knowledge of local gay, male educators. However, these educators understand that most men who have sex with men in the South Pacific do not self-identify as gay, but rather as men without any specific sexual identity who have sex with both men and women as they see fit. The sexual cultures of Papua New Guinea, India, Thailand, Australia, and Africa are considered.^ieng

Summary of track D: social science: research, policy and action.

SCOPE: This review summarizes the main issues discussed during Track D, which examined the societal impact of HIV/AIDS, and responses to the epidemic by individuals, families, communities and societies worldwide. Micro- and macrolevel issues addressed included the development, implementation and evaluation of programmes for prevention and care; policy development and implementation; structural issues such as the impact of gender relations, development and migration on the development of the epidemic; and the social and economic impact of HIV/AIDS on affected societies and communities. RECURRENT THEMES: Presentations provided strong evidence that peer-led, community-based programmes offer particularly effective ways of working, and that participatory research involving affected communities provides useful results for the design and evaluation of programmes and policies. This is the case across settings, issues, populations and countries. FUTURE DIRECTIONS: Emerging needs include how best to ensure sustainability of national and international responses, how best to scale up successful interventions for wider reach, and how best to work with systematically marginalized, neglected groups and populations. Research priorities include the characterization of the multiple determinants of HIV-related vulnerability, and the evaluation of interventions that take these complex determinants as their starting point. A more coherent and strategic response requires less separation between the different constituencies involved in AIDS work, and the more sustained involvement of people living with HIV/AIDS themselves.

Sustaining safe sex: a longitudinal study of a sample of homosexual men.

OBJECTIVE: TO assess the maintenance of safe sexual practice. (We use the term 'safe' sex throughout the paper, since 'safe' is the term adopted by the Australian National Committee on AIDS). DESIGN: Maintenance was assessed by comparing sexual behaviour with both regular and casual partners reported in a 1986/1987 survey (time 1) with behaviour reported in a second survey in 1991 (time 2). METHOD: The 145 homosexually active participants were a non-clinical sample recruited in 1986/1987 by advertisement and followed-up in 1991. A structured questionnaire was administered at both times. Items included questions about the nature of the men's sexual relationships and their sexual practices. RESULTS: Our findings indicate that the majority of men had sustained safe sex practices. HIV prevention strategies adopted included condom use, avoidance of anal intercourse and negotiated safety (i.e., the negotiated practice of unprotected anal intercourse within regular partnerships of concordant serostatus). CONCLUSIONS: Negotiated safety is not the same as relapse.

PIP: This study assesses the extent to which safe sex practices are being maintained in a longitudinally followed cohort of 145 homosexually active men. The nonclinical sample was recruited in 1986/87 by advertisements and followed-up in 1991 with questionnaires on the nature of their sexual relationships and their sexual practices. Sex behavior with regular partners was compared with sex behavior with casual partners over the time period. The majority had sustained safe sex practices including condom use, avoidance of anal intercourse, and negotiated safety. This latter practice refers to the negotiated practice of unprotected anal intercourse with regular partners of concordant serostatus and should not be considered a relapse to unsafe sex.

Social class, gay men and AIDS prevention.

The relationship between sexuality, gay communities and class is potentially a very large problem for AIDS prevention. Class is a historical process which interacts with sexuality in ways still little understood. The complexities of modern class structures need full acknowledgement; labour market groupings are internally divided, and cultural privilege and exclusion are important. A community survey in New South Wales of men who have sex with men shows the class selectiveness usual in such research. An exploration of correlates of labour market position, income and education finds few relationships with attachment to milieu except for involvement with gay organisations, and minor differences in broad measures of sexuality but some class differences in HIV risk-taking and some differences in exposure to information and in attitude. An exploration of several cases from a life-history study of working-class gay men shows the impact of class circumstance on the formation of sexual relationships and points to the accessibility of unlabelled homosexual activity in working-class milieux. Research on working-class education points to the importance of curriculum change in overcoming class exclusion, and is moving towards empowerment models of great relevance in AIDS education.