Vulnerabilidade ao HIV/AIDS e a prevenção da transmissão sexual entre casais sorodiscordantes

Este estudo descritivo e exploratório objetivou descrever e analisar a vulnerabilidade de casais sorodiscordantes ao HIV, e foi realizado em um Serviço Ambulatorial Especializado em aids de um município do estado de São Paulo. Os dados foram coletados através de entrevistas individuais com 11 portadores do HIV/AIDS, que convivem com parceria sabidamente sorodiscordante. Para organização e análise dos dados, empregamos o método de análise de Prosa e o conceito de vulnerabilidade como referencial teórico. A naturalização da infecção do HIV/aids como doença controlável por medicamentos, crença na impossibilidade de transmissão do HIV relacionadas com carga viral indetectável, sentimento de invencibilidade que surge com o tempo de convívio entre o casal, e sua influência na manutenção do sexo seguro são fatores de vulnerabilidade para a parceria sexual soronegativa. Serviços especializados no atendimento a indivíduos com HIV/aids necessitam incluir a parceria sexual nas ações educativas/preventivas promovidas pelos profissionais de saúde.

Do plants adjust their sex allocation and secondary sexual morphology in response to their neighbours?

BACKGROUND AND AIMS: Changes in the sex allocation (i.e. in pollen versus seed production) of hermaphroditic plants often occur in response to the environment. In some homosporous ferns, gametophytes choose their gender in response to chemical cues sent by neighbours, such that spores develop as male gametophytes if they perceive a female or hermaphrodite nearby. Here it is considered whether a similar process might occur in the androdioecious angiosperm species Mercurialis annua, in which males co-occur with hermaphrodites; previous work on a Spanish population of M. annua found that individuals were more likely to develop as males at high density. METHODS: Using a novel approach to treat plants with leachate from pots containing males or hermaphrodites of M. annua, the hypothesis that individuals assess their mating opportunities, and adjust their sex expression accordingly, was tested through an exchange of chemical cues through the soil. KEY RESULTS: For the population under study, from Morocco, no evidence was found for soil-signal-dependent sex expression: neither sex ratios nor sex allocation differed among experimental treatments. CONCLUSIONS: The results imply either that the Moroccan population under study behaves differently from that previously studied in Spain (pointing to potential geographical variation in plasticity for sex expression), or that our method failed to capture the signals used by M. annua for adjustment of sex expression.

Significado da violência sexual na manifestação da corporeidade: um estudo fenomenológico

Trata-se de pesquisa fenomenológica, que teve como objetivo compreender o significado da violência sexual na manifestação da corporeidade. Foi realizada no ambulatório de vítimas de violência sexual de um hospital universitário de Curitiba, de fevereiro a maio de 2007. Os discursos foram obtidos mediante a realização de entrevista aberta gravada com nove mulheres, e da análise emergiu o tema: Conviver com o medo no processo de coexistência. Constatou-se que o medo influenciou a vida social das mulheres, gerou insegurança, afetou o ser e estar no mundo, a sua corporeidade. Os profissionais da saúde devem ser capacitados, a fim de que possam perceber as mulheres vitimizadas em sua multidimensionalidade, para que suas ações de cuidado sejam não apenas instrumentais, voltadas à subjetividade, porque poderão ajudá-las a transcender o vivido e encontrar um novo sentido para a sua existência. Dessa forma, o atendimento será humanizado, ético e solidário.

Stable complexes involving acetylcholinesterase and amyloid-ß-peptide change the biochemical properties of the enzyme and increase the neurotoxicity of Alzheimer's fibrils

Brain acetylcholinesterase (AChE) forms stable complexes with amyloid-beta peptide (Abeta) during its assembly into filaments, in agreement with its colocalization with the Abeta deposits of Alzheimer's brain. The association of the enzyme with nascent Abeta aggregates occurs as early as after 30 min of incubation. Analysis of the catalytic activity of the AChE incorporated into these complexes shows an anomalous behavior reminiscent of the AChE associated with senile plaques, which includes a resistance to low pH, high substrate concentrations, and lower sensitivity to AChE inhibitors. Furthermore, the toxicity of the AChE-amyloid complexes is higher than that of the Abeta aggregates alone. Thus, in addition to its possible role as a heterogeneous nucleator during amyloid formation, AChE, by forming such stable complexes, may increase the neurotoxicity of Abeta fibrils and thus may determine the selective neuronal loss observed in Alzheimer's brain.

Les comportements face au VIH/sida des hommes qui ont des relations sexuelles avec des hommes: enquête Gaysurvey 2012

Gaysurvey est une enquête menée périodiquement en Suisse parmi les hommes qui ont des relations sexuelles avec des hommes (HSH). Elle s'inscrit dans le dispositif de surveillance du VIH, établi par l'Office fédéral de la santé publique, en tant qu'instrument de suivi des comportements face au VIH/Sida dans ce groupe cible. Elle a déjà été réalisée à neuf reprises : en 1987, 1990, 1992, 1994, 1997, 2000, 2004, 2007 et 2009. En 2010, l'enquête européenne EMIS a permis d'obtenir certains indicateurs qui sont présentés avec les données des enquêtes Gaysurvey lorsqu'ils sont disponibles. Les résultats de cette enquête servent directement au pilotage et à l'évaluation de la stratégie de lutte contre le VIH/Sida en Suisse, telle qu'elle a été définie par l'OFSP et ses partenaires. Elle permet d'établir des tendances temporelles au niveau des pratiques sexuelles et des expositions au risque d'infection par le VIH. Elle permet, en outre, d'approfondir certaines thématiques pertinentes pour le travail de prévention (gestion du risque au sein d'une relation stable, entrée dans la sexualité, pratiques de réduction des risques). Ce rapport a pour objectif de faire la synthèse des tendances, mises à jour lors de la dernière vague d'enquête réalisée en 2012. [Introduction p. 17]

Early maternal investment in mice: no evidence for compatible-genes sexual selection despite hybrid vigor.

Confronting a recently mated female with a strange male can induce a pregnancy block ('Bruce effect'). The physiology of this effect is well studied, but its functional significance is still not fully understood. The 'anticipated infanticide hypothesis' suggests that the pregnancy block serves to avoid the cost of embryogenesis and giving birth to offspring that are likely to be killed by a new territory holder. Some 'compatible-genes sexual selection hypotheses' suggest that the likelihood of a pregnancy block is also dependent on the female's perception of the stud's and the stimulus male's genetic quality. We used two inbred strains of mice (C57BL/6 and BALB/c) to test all possible combinations of female strain, stud strain, and stimulus strain under experimental conditions (N(total) = 241 mated females). As predicted from previous studies, we found increased rates of pregnancy blocks if stud and stimulus strains differed, and we found evidence for hybrid vigour in offspring of between-strain mating. Despite the observed heterosis, pregnancies of within-strain matings were not more likely to be blocked than pregnancies of between-strain matings. A power analysis revealed that if we missed an existing effect (type-II error), the effect must be very small. If a female gave birth, the number and weight of newborns were not significantly influenced by the stimulus males. In conclusion, we found no support for the 'compatible-genes sexual selection hypotheses'.

Convivendo com a diferença: o impacto da sorodiscordância na vida afetivo-sexual de portadores do HIV/AIDS

Este estudo descritivo exploratório e qualitativo objetivou descrever e analisar o impacto da sorodiscordância na vida afetivo-sexual de indivíduos com HIV/AIDS que convivem em parceria heterossexual e soronegativa ao HIV. Foram entrevistados 11 portadores do HIV/AIDS que realizavam acompanhamento clínico ambulatorial em um hospital universitário-referência do interior paulista. Os dados foram coletados através de entrevista individual gravada, e analisados segundo análise de Prosa. A vivência com a sorodiscordância ao HIV/AIDS impõe a esses casais o manejo de muitas dificuldades relacionadas à sua intimidade, diante da possibilidade de transmissão do HIV para o parceiro soronegativo, com impacto negativo na vivência da sexualidade entre parceiros sorodiscordantes, repercutindo em alterações da resposta sexual humana, favorecendo até mesmo a abstinência sexual. Apontamos a necessidade de atendimento por equipes interdisciplinares junto aos portadores do HIV/AIDS, e também de sua parceria sexual, proporcionando assistência integral, contemplando a sexualidade e as dificuldades advindas com a sorodiscordância.

Sexual dysfunctions among young men: prevalence and associated factors.

PURPOSE: The purposes of this study are to measure the prevalence of premature ejaculation (PE) and erectile dysfunction (ED) among a population of Swiss young men and to assess which factors are associated with these sexual dysfunctions in this age-group. METHODS: For each condition (PE and ED), we performed separate analyses comparing young men suffering from the condition with those who were not. Groups were compared for substance use (tobacco, alcohol, cannabis, other illegal drugs, and medication without a prescription), self-reported body mass index, sexual orientation, physical activity, professional activity, sexual experience (sexual life length and age at first intercourse), depression status, mental health, and physical health in a bivariate analysis. We then used a log-linear analysis to consider all significant variables simultaneously. RESULTS: Prevalence rates for PE and ED were 11% and 30%, respectively. Poor mental health was the only variable to have a direct association with both conditions after controlling for potential confounders. In addition, PE was directly associated with tobacco, illegal drugs, professional activity, and physical activity, whereas ED was directly linked with medication without a prescription, length of sexual life, and physical health. CONCLUSIONS: In Switzerland, one-third of young men suffer from at least one sexual dysfunction. Multiple health-compromising factors are associated with these dysfunctions. These should act as red flags for health professionals to encourage them to take any opportunity to talk about sexuality with their young male patients.

Genetic causes of transitions from sexual reproduction to asexuality in plants and animals.

The persistence of sexual reproduction in the face of competition from asexual invaders is more likely if asexual lineages are produced infrequently or have low fitness. The generation rate and success of new asexual lineages will be influenced by the proximate mechanisms underlying transitions to asexuality. As such, characterization of these mechanisms can help explain the distribution of reproductive modes among natural populations. Here, we synthesize the literature addressing proximate causes of transitions from sexual to asexual reproduction in plants and animals. In cyclical and facultatively asexual taxa, individual mutations can cause obligate asexuality. The evolution of asexuality in obligately sexual groups is more complex, requiring the simultaneous acquisition of two traits generally controlled by different genetic factors: unreduced gamete formation and spontaneous development of unfertilized gametes. At least three 'pre-adaptations' could favour transitions to obligate asexuality in obligate sexuals. First, linkage among loci affecting separate key components of asexuality facilitates its spread, with evidence for these linkage blocks in plants. Second, asexuality should evolve more readily in haplodiploids; support for this hypothesis comes from two examples where a single locus causes transitions to asexuality. Third, standing genetic variation for the production of unreduced gametes could facilitate transitions to asexuality, but whether the ability to produce unreduced gametes contributes to the evolution of obligate asexuality remains unclear. We close by reviewing the associations between asexuality, hybridization and polyploidy, and argue that current data suggest that hybridization is more likely to play a causal role in transitions to asexuality than polyploidy.

Estilos de vida na adolescência: comportamento sexual dos adolescentes portugueses

Estudos recentes têm demonstrado que actualmente os adolescentes iniciam a vida sexual cada vez mais cedo, sem contudo possuírem uma educação sexual consistente. Os objectivos deste estudo foram analisar o comportamento sexual de adolescentes do ensino secundário e identificar os hábitos de vigilância de saúde sexual em adolescentes, do ensino secundário, sexualmente activos. Realizou-se um estudo exploratório em que participaram 680 adolescentes, com idades entre 15 e 19 anos. Os resultados evidenciam que a maioria dos inquiridos ainda não iniciou a actividade sexual; são os rapazes os que mais reportam já ter tido relações sexuais; o preservativo não é um método utilizado por todos os adolescentes nas suas relações sexuais; a maioria dos adolescentes não faz vigilância de saúde sexual. É importante que os adolescentes sexualmente activos recebam cuidados de saúde e aconselhamento. As instituições de saúde e os seus profissionais necessitam de ser pró-activos tentando captar os adolescentes.

Adolescentes em cena: uma proposta educativa no campo da saúde sexual e reprodutiva

Objetivou-se descrever a experiência sobre a elaboração de material educativo, no formato de performance teatral criada e encenada por adolescentes, como estratégia para a obtenção de uma atitude reflexiva e autônoma desses sujeitos, no campo afetivo-sexual e reprodutivo. Processo de intervenção e de investigação desenvolvido em uma escola pública de Belo Horizonte - Minas Gerais, Brasil - com 12 estudantes de 14 a 18 anos. A análise baseou-se no método de educação pela experiência, de John Dewey. Foram realizadas 23 oficinas até a produção do espetáculo e do vídeo Sexo sim, Doença Não, exibido para alunos do ensino médio. A produção de tecnologias educativas, construída pelos próprios adolescentes, possibilitou a ampliação de suas vivências e a re-significação de conhecimentos. Também auxiliou a compreensão da realidade cotidiana desses sujeitos, permitindo a ligação entre o interno (o pensamento do adolescente) e o externo (que concretiza os fenômenos sociais) no campo afetivo-sexual e reprodutivo.

Management of the risk of HIV infection in male homosexual couples.

OBJECTIVES: To study the ways of managing HIV risk within male homosexual steady relationships (gay couples), including factors associated with consistent condom use during anal sex with the steady partner.¦METHOD: An anonymous and standardized questionnaire completed by a convenience sample of homosexuals in Switzerland in 1997 (n = 1097). Information on the couple was provided by the 74% (n = 786) of male respondents who reported having a steady partner in the past 12 months. Data were analysed by contingency tables and logistic regression.¦RESULTS: Different ways of managing HIV risk were reported: negotiated safety (both HIV negative, condoms abandoned) was chosen by one quarter of the couples, but the most frequent solution was reliance on condoms for anal sex, chosen by more than four in 10. Altogether 84% of couples exhibited safe management of HIV risk within their partnership. The 16% of couples showing inadequate management of HIV risk within the couple mostly relied on questionable assumptions about past or present risks. A total of 74% of couples had spoken about managing HIV risk with possible casual partners. Reported behaviour with the steady partner and with casual partners was highly consistent with claimed strategies chosen to manage HIV risk. Consistent condom use with the steady partner was mostly associated with variables characterizing the relationship: initial 2 years of the relationship, discordant or unknown serological HIV status, non-exclusivity.¦CONCLUSION: Gay couples manage HIV risk in a variety of ways. Most strategies provide adequate protection with casual partners, but leave gaps in protection between the steady partners themselves.

A qui li dic? : la detecció de l’abús sexual infantil i el traspàs d’informació entre professionals

Aquest treball s'estructura en una primera part de fonamentació teòrica. El procediment que s'ha seguit ha estat la recerca bibliogràfica. Es basa en els aspectes tècnics a tenir en compte per la detecció de l' Abusos Sexuals Infantils (ASI), la ubicació dels Serveis Bàsics d'Atenció Social (SBAS) dins el sistema català de serveis socials, el marc jurídic dels drets i de la protecció a la infància i l'adolescència així com de qüestions relatives al tractament de dades, de la confidencialitat de les informacions de què disposem els/les professionals, l'obligació de secret, complementat amb la deontologia professional, que ens pot orientar a l'hora de prendre les decisions més adequades a la nostra praxi. La segona part del treball és empírica. El procediment ha estat portar a terme un grup de reflexió ètica amb professionals del Consorci de Benestar Social del Pla de l'Estany-Banyoles. Partint de casos pràctics de sospita d'ASI, les persones participants han concretat els principals problemes (alguns dels quals relacionats amb l'ètica aplicada) davant els quals s'han trobat a la fase de detecció/intervenció. Les aportacions extretes de les diferents sessions en les quals es van treballar part dels objectius d'aquesta recerca ens permeten concretar la realitat i una primera deliberació sobre quina podria ser la bona pràctica general. La tercera part utilitza la fonamentació teòrica i els material del treball de camp per presentar la reflexió final que pretén donar resposta als objectius plantejats en aquesta recerca

Effect of mating history on gender preference in the hermaphroditic snail physa acuta

Several internally fertilizing hermaphroditic animals can only perform one sexual role at a time. In such species, two individuals that engage in a copulation may have different interests in acting as male or female. A gender choice must be made which, if both individuals have the same preference, may give rise to a severe sexual conflict. Here we tested the hypothesis that gender choice could be influenced by mating history, using the freshwater snail, Physa acuta. We recorded the copulatory behaviour of 240 pairs composed of a focal individual and a partner, each either short- or long-isolated. We found that the time to the first copulation was unaffected by isolation status, suggesting that first contacts in this species are random processes. In contrast, the duration of copulations and the frequency of rejection behaviours suggested that individual gender preference switches from male biased to female biased as isolation increases. In addition, snails rejected copulations more frequently when presented to a partner with the same isolation status. Reciprocity, measured as the rate of gender swapping between the first and second copulations, was high irrespective of gender status. We suggest possible evolutionary causes for this gender preference switch and discuss its potential importance in natural population as well as its consequences for the maintenance of hermaphroditism

Alpha1-adrenoceptors are required for normal male sexual function.

BACKGROUND AND PURPOSE: Alpha(1)-adrenoceptor antagonists are extensively used in the treatment of hypertension and lower urinary tract symptoms associated with benign prostatic hyperplasia. Among the side effects, ejaculatory dysfunction occurs more frequently with drugs that are relatively selective for alpha(1A)-adrenoceptors compared with other drugs of this class. This suggests that alpha(1A)-adrenoceptors may contribute to ejaculation. However, this has not been studied at the molecular level. EXPERIMENTAL APPROACH: The physiological contribution of each alpha(1)-adrenoceptor subtype was characterized using alpha(1)-adrenoceptor subtype-selective knockout (KO) mice (alpha(1A)-, alpha(1B)- and alpha(1D)-AR KO mice) since the subtype-specific drugs available are only moderately selective. We analysed the role of alpha(1)-adrenoceptors in the blood pressure and vascular response as well as ejaculation by determining these variables in alpha(1)-adrenoceptor subtype-selective KO mice and in mice with all their alpha(1)-adrenoceptor subtypes deleted (alpha(1)-AR triple-KO mice). KEY RESULTS: The pregnancy rate was reduced by 50% in alpha(1A)-adrenoceptor KO mice, and this reduction was dramatically enhanced in alpha(1)-adrenoceptor triple-KO mice. Contractile tension of the vas deferens in response to noradrenaline was markedly decreased in alpha(1A)-adrenoceptor KO mice, and this contraction was completely abolished in alpha(1)-adrenoceptor triple-KO mice. This attenuation of contractility was also observed in the electrically stimulated vas deferens. CONCLUSIONS AND IMPLICATIONS: These results demonstrate that alpha(1)-adrenoceptors, particularly alpha(1A)-adrenoceptors, are required for normal contractility of the vas deferens and consequent sperm ejaculation as well as having a function in fertility.