95 research outputs found

    Childhood sexual experiences with an older partner among men who have sex with men in Buenos Aires, Argentina

    Get PDF
    This study sought to describe childhood sexual experiences with older partners (CSEOP) among men who have sex with men (MSM) in Buenos Aires, Argentina. MSM were recruited through respondent driven sampling. They responded to a computer administered self-interview with questions on CSEOP, operationalized as manual, oral, genital, or anal contact prior to age 13 with a partner at least 4 years older. Of the 500 respondents, only 25% identified as gay. Eighteen percent of the respondents reported CSEOP, the majority of whom did not feel they were hurt by the experience and did not consider it to be childhood sexual abuse (CSA). Over two-thirds of MSM who reported CSEOP said that their older partner was a female. Only 4% of those with a female partner felt their experience was CSA compared to 44% of those who had a male partner. Among all men reporting CSEOP, those who felt sexually abused were more likely to have been physically forced or threatened, physically hurt, and emotionally hurt than those who did not feel sexually abused. Having CSEOP, being hurt by the experiences, and perceiving the experiences as sexual abuse were not associated with current HIV sexual risk or substance use behavior. In this sample of MSM in Argentina, a substantial minority reported CSEOP. Those who felt they had been sexually abused were much more likely to have had an older male partner than an older female partner, and were more likely to report having been physically forced and threatened by their older partner.Fil: Dolezal, Curtis. Columbia University; Estados UnidosFil: Carballo Diéguez, A.. Columbia University; Estados UnidosFil: Balán, Iván C.. Columbia University; Estados UnidosFil: Pando, María de los Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Mabragaña, Marina. Columbia University; Estados UnidosFil: Marone, Ruben. Nexo Asociación Civil; ArgentinaFil: Barreda, Victoria. Nexo Asociación Civil; ArgentinaFil: Ávila, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentin

    High genetic variability of HIV-1 in female sex workers from Argentina

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>A cross-sectional study on 625 Female Sex Workers (FSWs) was conducted between 2000 and 2002 in 6 cities in Argentina. This study describes the genetic diversity and the resistance profile of the HIV-infected subjects.</p> <p>Results</p> <p>Seventeen samples from HIV positive FSWs were genotyped by <it>env </it>HMA, showing the presence of 9 subtype F, 6 subtype B and 2 subtype C. Sequence analysis of the protease/RT region on 16 of these showed that 10 were BF recombinants, three were subtype B, two were subtype C, and one sample presented a dual infection with subtype B and a BF recombinant. Full-length genomes of five of the protease/RT BF recombinants were also sequenced, showing that three of them were CRF12_BF. One FSW had a dual HIV-1 infection with subtype B and a BF recombinant. The B sections of the BF recombinant clustered closely with the pure B sequence isolated from the same patient. Major resistance mutations to antiretroviral drugs were found in 3 of 16 (18.8%) strains.</p> <p>Conclusion</p> <p>The genetic diversity of HIV strains among FSWs in Argentina was extensive; about three-quarters of the samples were infected with diverse BF recombinants, near twenty percent had primary ART resistance and one sample presented a dual infection. Heterosexual transmission of genetically diverse, drug resistant strains among FSWs and their clients represents an important and underestimated threat, in Argentina.</p

    Use of Respondent Driven Sampling (RDS) Generates a Very Diverse Sample of Men Who Have Sex with Men (MSM) in Buenos Aires, Argentina

    Get PDF
    Prior research focusing on men who have sex with men (MSM) conducted in Buenos Aires, Argentina, used convenience samples that included mainly gay identified men. To increase MSM sample representativeness, we used Respondent Driven Sampling (RDS) for the first time in Argentina. Using RDS, under certain specified conditions, the observed estimates for the percentage of the population with a specific trait are asymptotically unbiased. We describe, the diversity of the recruited sample, from the point of view of sexual orientation, and contrast the different subgroups in terms of their HIV sexual risk behavior.500 MSM were recruited using RDS. Behavioral data were collected through face-to-face interviews and Web-based CASI.In contrast with prior studies, RDS generated a very diverse sample of MSM from a sexual identity perspective. Only 24.5% of participants identified as gay; 36.2% identified as bisexual, 21.9% as heterosexual, and 17.4% were grouped as "other." Gay and non-gay identified MSM differed significantly in their sexual behavior, the former having higher numbers of partners, more frequent sexual contacts and less frequency of condom use. One third of the men (gay, 3%; bisexual, 34%, heterosexual, 51%; other, 49%) reported having had sex with men, women and transvestites in the two months prior to the interview. This population requires further study and, potentially, HIV prevention strategies tailored to such diversity of partnerships. Our results highlight the potential effectiveness of using RDS to reach non-gay identified MSM. They also present lessons learned in the implementation of RDS to recruit MSM concerning both the importance and limitations of formative work, the need to tailor incentives to circumstances of the less affluent potential participants, the need to prevent masking, and the challenge of assessing network size

    Low frequency of male circumcision and unwillingness to be circumcised among MSM in Buenos Aires, Argentina: association with sexually transmitted infections

    Get PDF
    Abstract Objective: The aims of this study were to investigate the frequency of male circumcision among men who have sex with men (MSM) in Buenos Aires, Argentina; the association between circumcision and sexually transmitted infections (STIs); and, among those uncircumcised, the willingness to be circumcised. Methods: A cross-sectional study was conducted among 500 MSM recruited through the respondent-driven sampling (RDS) technique. Participants underwent a consent process, responded to a Web-based survey that included questions on demographic information, sexual behaviour, and circumcision and provided biological samples. HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), Treponema pallidum, and human papiloma virus (HPV) diagnoses were performed using standard methodologies. For all analyses, data were weighted based on participants&apos; network size. Results: Only 64 (13%) of the 500 MSM in our study reported being circumcised. Among uncircumcised men (n 0418), 302 (70.4%) said that they would not be willing to get circumcised even if the procedure could reduce the risk of HIV infection. When considering all participants, circumcision status was not significantly associated with HIV, HBV, HCV, T. pallidum or HPV infections. However, when we restricted the sample to men who do not practice receptive anal intercourse (RAI) and compared circumcised to uncircumcised men, the former (N033) had no cases of HIV infection, while 34 of 231 (14.8%) uncircumcised men were HIV positive (p 00.020). Regarding HPV, uncircumcised men had a significantly larger number of different HPV types compared with circumcised men (mean 1.83 vs. 1.09, pB0.001) and a higher frequency of high-risk-HPV genotypes (47.6% vs. 12.5%, p 00.012). Conclusions: Consistent with international evidence, male circumcision appears to have a partial protective effect among MSM. The efficacy of circumcision in reducing risk of HIV infection among MSM appears to be correlated with sexual practices. Given the lack of motivation among MSM with regard to circumcision, proper awareness on the risks and benefits of circumcision needs to be created, if circumcision has to be introduced as a prevention strategy

    VRK1 (Y213H) homozygous mutant impairs Cajal bodies in a hereditary case of distal motor neuropathy.

    Get PDF
    Background: Distal motor neuropathies with a genetic origin have a heterogeneous clinical presentation with overlapping features affecting distal nerves and including spinal muscular atrophies and amyotrophic lateral sclerosis. This indicates that their genetic background is heterogeneous. Patient and methods: In this work, we have identified and characterized the genetic and molecular base of a patient with a distal sensorimotor neuropathy of unknown origin. For this study, we performed whole-exome sequencing, molecular modelling, cloning and expression of mutant gene, and biochemical and cell biology analysis of the mutant protein. Results: A novel homozygous recessive mutation in the human VRK1 gene, coding for a chromatin kinase, causing a substitution (c.637T > C; p.Tyr213His) in exon 8, was detected in a patient presenting since childhood a progressive distal sensorimotor neuropathy and spinal muscular atrophy syndrome, with normal intellectual development. Molecular modelling predicted this mutant VRK1 has altered the kinase activation loop by disrupting its interaction with the C-terminal regulatory region. The p.Y213H mutant protein has a reduced kinase activity with different substrates, including histones H3 and H2AX, proteins involved in DNA damage responses, such as p53 and 53BP1, and coilin, the scaffold for Cajal bodies. The mutant VRK1(Y213H) protein is unable to rescue the formation of Cajal bodies assembled on coilin, in the absence of wild-type VRK1. Conclusion: The VRK1(Y213H) mutant protein alters the activation loop, impairs the kinase activity of VRK1 causing a functional insufficiency that impairs the formation of Cajal bodies assembled on coilin, a protein that regulates SMN1 and Cajal body formation.post-print2120 K

    First report of an HIV-1 triple recombinant of subtypes B, C and F in Buenos Aires, Argentina

    Get PDF
    We describe the genetic diversity of currently transmitted strains of HIV-1 in men who have sex with men (MSM) in Buenos Aires, Argentina between 2000 and 2004. Nearly full-length sequence analysis of 10 samples showed that 6 were subtype B, 3 were BF recombinant and 1 was a triple recombinant of subtypes B, C and F. The 3 BF recombinants were 3 different unique recombinant forms. Full genome analysis of one strain that was subtype F when sequenced in pol was found to be a triple recombinant. Gag and pol were predominantly subtype F, while gp120 was subtype B; there were regions of subtype C interspersed throughout. The young man infected with this strain reported multiple sexual partners and sero-converted between May and November of 2004. This study reported for the first time the full genome analysis of a triple recombinant between subtypes B, C and F, that combines in one virus the three most common subtypes in South America

    Solubility of the metal precursor Ni(NO3)2⋅6H2O in high-pressure CO2 + ethanol mixtures

    Get PDF
    The solubility of Ni(NO3)2⋅6H2O in high-pressure CO2 + ethanol mixtures was measured using a high-pressure variable-volume view cell from (308.2 to 353.2 K) and up to 25.0 MPa. This compound has been used previously as a Ni precursor in metal deposition experiments using supercritical CO2. Ni(NO3)2•6H2O was not soluble in pure CO2 but the addition of ethanol into the system allowed the solubilisation of the hydrated salt in the mixture. Mole fraction of Ni(NO3)2•6H2O varied from 1.67 10-4 to 1.97 10-3. At these salt concentrations, the phase diagram of the CO2 + EtOH + Ni(NO3)2⋅6H2O system resembled that of the CO2 + EtOH binary system and, at the studied conditions, a vapourliquid equilibrium was observed. For the higher ethanol concentrations, the bubble points closely matched those of the CO2 + EtOH system. For the lower EtOH concentrations, however, much higher solubilisation pressures were required, due to the release of water molecules from the salt into the solution. Ni(NO3)2⋅6H2O solutions were stable in highpressure CO2 + EtOH mixtures at the studied conditions

    HIV and Other Sexually Transmitted Infections among Men Who Have Sex with Men Recruited by RDS in Buenos Aires, Argentina: High HIV and HPV Infection

    Get PDF
    The aim of this study was to estimate the prevalence of HIV and other STIs, among MSM from Buenos Aires (2007-2009).Responding Driven Sampling was used for recruitment of MSM. Participants completed a structured web-based survey and provided biological samples.A total of 496 MSM were studied for HIV, HBV, HCV, and T. pallidum infections. Chlamydia and HPV diagnoses were only performed in 98 and 109 participants, respectively. Prevalence of HIV was 17.3%, HBV 22.9%, HCV 7.5%, T. pallidum 20.5%, HPV 83.5%, and C. trachomatis 1.7%. In the year prior to the evaluation, 71% of the participants had had sex with men and/or trans and women (MMW) while 29% had not had sex with women (MM). Comparing MM to MMW, prevalence of HIV (30.7% vs. 11.9%, p<0.001), HBV (36.4% vs. 17.8%, p<0.001), T. pallidum (32.1% vs. 15.7%, p<0.001), and HPV (88.3% vs. 70.4%, p = 0.039) were significantly higher among MM, whereas no significant differences were found for HCV and C. trachomatis. The MM group had also significantly higher HIV incidence (5.60 vs. 4.28 per 100 persons-year, p = 0.032). HPV genotypes 16, 6, and 11 were the most frequently found; 40.7% of the MSM had more than one genotype and one high risk genotype was detected in 43.6% of participants.Both MM and MMW are at high risk of infection for HIV and other STIs. Rates of HIV, HBV, T. pallidum and HPV infections are higher in the MM group

    P07-05. HIV and STI prevalence among men who have sex with men (MSM) recruited through respondent driven sampling (RDS) in Buenos Aires, Argentina

    Get PDF
    Fil: Pando, María A. Centro Nacional de Referencia para el SIDA; Argentina.Fil: Marone, Rubén. Nexo Asociación Civil; Argentina.Fil: Balán, Iván C. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Dolezal, Curtis. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Squiquera, Luis. Nexo Asociación Civil; Argentina. Fil: Balan, Iván C. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Picconi, María Alejandra. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio Virus Oncogénicos; Argentina.Fil: Gonzales, J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio Virus Oncogénicos; Argentina.Fil: Rey, Jorge. Hospital de Clínicas José de San Martín; Argentina.Fil: Fernandez Toscano, M. Hospital de Clínicas José de San Martín; Argentina.Fil: Rodriguez Fermepín, Marcelo. UBA. Laboratorio de Inmunología Clínica; Argentina.Fil: Gallo Vaulet, Lucia. UBA. Laboratorio de Inmunología Clínica; Argentina.Fil: Carballo Dieguez, Alex. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Avila, María M. Centro Nacional de Referencia para el SIDA; Argentina.Background MSM constitute one of the populations most affected by HIV and other STIs in Argentina. Previous prevalence studies were based on convenience samples. RDS, a methodology designed to access hidden populations, is being used for the first time in Argentina to recruit MSM. Methods RDS recruitment started in November 2007 with 16 first generation participants (seeds) who were selected for their potential to tap in MSM networks. Recruitment is ongoing. Men must be 18 years of age or older, be residents of Buenos Aires, self-report having sex with men at least 10 times in their lives and at least once in the past six months. They must have a coupon indicating they have been referred by a study participant. Specimens are being collected for HIV and STI diagnosis. All data are weighted using the RDS Analysis Tool (RDSAT). Results To date, 333 MSM were recruited through RDS showing a prevalence of 11.3, 16.6, 7.9, 17.6, 4.0 and 88.3% for HIV, HBV, HCV, T. pallidum, Chlamydia and HPV, respectively. Chlamydia and HPV diagnoses were only performed in 73 and 79 participants, respectively. Among HPV positive individuals, 47.8% had almost one of these high risk types (16, 58, 33, 45, 18 and 31) and 32% had multiple infections with 2 or more types. Conclusion Compared with previous studies, these results show similar HIV, HBV and T. pallidum prevalences but higher HCV prevalence. For the first time, an elevated prevalence of HPV was detected on MSM, with high frequency of types associated with ano-genital cancer. Preliminary analyses of socio demographic data show that RDS helps recruit a diversity of MSM, particularly of lower socio-economic level usually missed with other recruitment methods. The high prevalence of coinfections in this population should be taken into account if MSM are part of vaccine trials given that STI may increase HIV sexual transmission

    P07-05. HIV and STI prevalence among men who have sex with men (MSM) recruited through respondent driven sampling (RDS) in Buenos Aires, Argentina

    Get PDF
    Fil: Pando, María A. Centro Nacional de Referencia para el SIDA; Argentina.Fil: Marone, Rubén. Nexo Asociación Civil; Argentina.Fil: Balán, Iván C. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Dolezal, Curtis. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Squiquera, Luis. Nexo Asociación Civil; Argentina. Fil: Balan, Iván C. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Picconi, María Alejandra. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio Virus Oncogénicos; Argentina.Fil: Gonzales, J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio Virus Oncogénicos; Argentina.Fil: Rey, Jorge. Hospital de Clínicas José de San Martín; Argentina.Fil: Fernandez Toscano, M. Hospital de Clínicas José de San Martín; Argentina.Fil: Rodriguez Fermepín, Marcelo. UBA. Laboratorio de Inmunología Clínica; Argentina.Fil: Gallo Vaulet, Lucia. UBA. Laboratorio de Inmunología Clínica; Argentina.Fil: Carballo Dieguez, Alex. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Avila, María M. Centro Nacional de Referencia para el SIDA; Argentina.Background MSM constitute one of the populations most affected by HIV and other STIs in Argentina. Previous prevalence studies were based on convenience samples. RDS, a methodology designed to access hidden populations, is being used for the first time in Argentina to recruit MSM. Methods RDS recruitment started in November 2007 with 16 first generation participants (seeds) who were selected for their potential to tap in MSM networks. Recruitment is ongoing. Men must be 18 years of age or older, be residents of Buenos Aires, self-report having sex with men at least 10 times in their lives and at least once in the past six months. They must have a coupon indicating they have been referred by a study participant. Specimens are being collected for HIV and STI diagnosis. All data are weighted using the RDS Analysis Tool (RDSAT). Results To date, 333 MSM were recruited through RDS showing a prevalence of 11.3, 16.6, 7.9, 17.6, 4.0 and 88.3% for HIV, HBV, HCV, T. pallidum, Chlamydia and HPV, respectively. Chlamydia and HPV diagnoses were only performed in 73 and 79 participants, respectively. Among HPV positive individuals, 47.8% had almost one of these high risk types (16, 58, 33, 45, 18 and 31) and 32% had multiple infections with 2 or more types. Conclusion Compared with previous studies, these results show similar HIV, HBV and T. pallidum prevalences but higher HCV prevalence. For the first time, an elevated prevalence of HPV was detected on MSM, with high frequency of types associated with ano-genital cancer. Preliminary analyses of socio demographic data show that RDS helps recruit a diversity of MSM, particularly of lower socio-economic level usually missed with other recruitment methods. The high prevalence of coinfections in this population should be taken into account if MSM are part of vaccine trials given that STI may increase HIV sexual transmission
    corecore