The Role of MicroRNAs in HIV Infection.

MicroRNAs (miRNAs), a class of small, non-coding RNAs, play a pivotal role in regulating gene expression at the post-transcriptional level. These regulatory molecules are integral to many biological processes and have been implicated in the pathogenesis of various diseases, including Human Immunodeficiency Virus (HIV) infection. This review aims to cover the current understanding of the multifaceted roles miRNAs assume in the context of HIV infection and pathogenesis.

SARS-CoV-2-Specific IgG and IgA response in maternal blood and breastmilk of vaccinated naïve and convalescent lactating participants.

Background: Recent studies have shown the presence of SARS-CoV-2-specific antibodies in the milk of breastfeeding mothers vaccinated with mRNA and convalescent. However, limited information is available in lactating women receiving other vaccine platforms used in developing countries, such as the inactivated SARS-CoV-2 vaccine BBIBP-CorV (Sinopharm) and the non-replicating adenovirus vaccines Sputnik V (Gamaleya Institute) and ChAdOx1-S (Oxford AstraZeneca).

Methods: Here, we evaluated anti-SARS-CoV-2 IgG and IgA levels in both serum and milk samples using a longitudinal and a cross-sectional cohort of 208 breastfeeding vaccinated women from Argentina with or without previous SARS-CoV-2 infection.

High frequency of Nichols-like strains and increased levels of macrolide resistance in Treponema pallidum in clinical samples from Buenos Aires, Argentina.

Globally, 94% of Treponema pallidum subsp. pallidum (TPA) clinical strains belong to the SS14-like group and 6% to the Nichols-like group, with a prevalence of macrolide resistance of 90%. Our goal was to determine whether local TPA strain distribution and macrolide resistance frequency have changed significantly since our last report, which revealed that Buenos Aires had a high frequency of Nichols-like strains (27%) and low levels of macrolide resistance (14%).

Multilocus sequence typing of in children with acquired syphilis by nonsexual contact.

There are scarce data of subsp. (TPA) characterization in children with syphilis. Nonsexually acquired transmission (NSAT) of TPA is possible in infants through close contact.

[Evaluation of interventions during the COVID-19 pandemic: development of a model based on subpopulations with different contact rates].

Although multiple attempts have been made to mathematically model the current epidemic of SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19), few models have been conceived as accessible interactive tools for users from various backgrounds. The goal of this study was to develop a model that took into account the heterogeneity in contact rates within the population and to implement it in an accessible application allowing to estimate the impact of possible interventions based on available information. An extended version of the Susceptible-Exposed-Infected-Resistant (SEIR) model, named SEIR-HL, was developed, assuming a population divided into two subpopulations, with different contact rates.

Viral hepatitis and Treponema pallidum prevalence in persons who underwent premarital blood tests in Argentina.

The objective of this study was to estimate the prevalence of different serological markers of hepatitis A, B and C viruses and Treponema pallidum among the adult population of Argentina. To achieve this, adults who attended health services for premarital exams (which are mandatory and includes screening for syphilis) were recruited. A cross-sectional study was designed with a cluster sampling strategy.

Evaluation of the utility of a rapid test for syphilis at a sexually transmitted disease clinic in Buenos Aires, Argentina.

Even though syphilis can be easily diagnosed by simple and low-cost laboratory methods, it continues to be an important health problem. Rapid tests (RT) for the detection of treponemal antibodies can facilitate earlier diagnosis, access to treatment and linkage to care. The aim of this study was to analyse the usefulness of the incorporation of a RT in the detection of patients infected with T.

Genomic characterization and molecular evolution analysis of subtype B and BF recombinant HIV-1 strains among Argentinean men who have sex with men reveal a complex scenario.

Currently, data on HIV-1 circulating strains among men who have sex with men (MSM) in Argentina is scarce. In South America, the distribution and the prevalence of BF recombinants are dissimilar and exhibit an underappreciated heterogeneity of recombinant structures. Here, we studied for the first time the genetic diversity of HIV-1 BF recombinants and their evolution over time through in-depth phylogenetic analysis and multiple recombination detection methods involving 337 HIV-1 nucleotide sequences (25 near full-length (NFL) and 312 partial pol gene) obtained from Argentinean MSM.

High Substance Use and HIV Risk Behavior Among Young Argentine Men Who Have Sex with Men.

In the United States young men who have sex with men have higher rates of substance use, higher HIV incidence, and less frequent HIV testing than their heterosexual counterparts and older MSM. Less is known about comparable populations in Latin America. As part of an epidemiological study, MSM were recruited through Respondent Driven Sampling in the metropolitan area of Buenos Aires, Argentina and answered a computerized behavioral survey.

High acceptability of rapid HIV self-testing among a diverse sample of MSM from Buenos Aires, Argentina.

Introduction: The objective of this study was to explore the acceptability of rapid HIV self-testing (RHST) among men who have sex with men (MSM).

Methods: During 2006-2009, a sample of 500 MSM was recruited through Respondent Driven Sampling for an HIV prevalence/incidence study. Attitude toward RHST was explored among HIV negative MSM.

High Frequency of Illegal Drug Use Influences Condom Use Among Female Transgender Sex Workers in Argentina: Impact on HIV and Syphilis Infections.

The high prevalence of HIV and syphilis found among female transgender sex workers (FTSWs) in Argentina calls for the study of factors leading to negative health consequences. Given the particular characteristics observed in this population (high marginalization, school dropout, and low adherence to healthcare services), we explored the association of several socio-demographic characteristics with syphilis and HIV infections, and the determinants of condom use. This study revealed that FTSWs from Argentina were exposed to several risk factors decreasing thus their ability to negotiate condom use and leading to increased risk for transmission of HIV and other sexually transmitted infections (STIs).

Molecular typing of Treponema pallidum isolates from Buenos Aires, Argentina: Frequent Nichols-like isolates and low levels of macrolide resistance.

A total of 54 clinical samples, including genital lesion swabs, whole blood and cerebrospinal fluid from patients diagnosed with syphilis were collected in 2006 and in 2013 in Buenos Aires, Argentina. Treponemal DNA was detected in 43 of the analyzed samples (79.6%) and further analyzed using Sequencing-based molecular typing (SBMT) and Enhanced CDC-typing (ECDCT).

Origin of modern syphilis and emergence of a pandemic Treponema pallidum cluster.

The abrupt onslaught of the syphilis pandemic that started in the late fifteenth century established this devastating infectious disease as one of the most feared in human history. Surprisingly, despite the availability of effective antibiotic treatment since the mid-twentieth century, this bacterial infection, which is caused by Treponema pallidum subsp. pallidum (TPA), has been re-emerging globally in the last few decades with an estimated 10.

[Summary of the LINKS Study: Factors associated with HIV infection among men who have sex with men in Buenos Aires, Argentina].

This article summarizes published findings from Project LINKS. A total of 500 men who have sex with men were recruited through Respondent Driven Sampling into this study on factors associated with HIV infection. Among participants, 24.

HIV status disclosure among infected men who have sex with men (MSM) in Buenos Aires, Argentina.

Five hundred men who have sex with men were recruited in Buenos Aires using respondent driven sampling. Of them, 46 respondents (24 of them not gay identified) who were HIV infected were asked questions on serodisclosure. The sample was characterized by indicators of low socioeconomic status.

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

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.

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

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 testing practices among men who have sex with men in Buenos Aires, Argentina.

The objective of the study was to explore HIV-testing practices among men who have sex with men (MSM) in Buenos Aires, Argentina, in light of current international health guidelines that recommend frequent HIV testing for MSM who engage in high-risk behavior. Participants, who were recruited using respondent-driven sampling (RDS), were 500 mostly young, nongay-identified MSM of low socioeconomic status, high levels of unemployment, living mainly in the less-affluent areas surrounding Buenos Aires, and lacking health insurance. They provided blood samples for HIV testing and responded to a Computer Assisted Self Interview.

Early Gag immunodominance of the HIV-specific T-cell response during acute/early infection is associated with higher CD8+ T-cell antiviral activity and correlates with preservation of the CD4+ T-cell compartment.

The important role of the CD8(+) T-cell response on HIV control is well established. Moreover, the acute phase of infection represents a proper scenario to delineate the antiviral cellular functions that best correlate with control. Here, multiple functional aspects (specificity, ex vivo viral inhibitory activity [VIA] and polyfunctionality) of the HIV-specific CD8(+) T-cell subset arising early after infection, and their association with disease progression markers, were examined.

HIV knowledge and beliefs among men who have sex with men (MSM) in Buenos Aires, Argentina.

Five hundred men who have sex with men (MSM), recruited through respondent driven sampling in Buenos Aires, Argentina, were interviewed in order to assess knowledge and beliefs about HIV infection. The mean proportion of HIV correct knowledge answers was 62 %; however participants whose sexual partners in the prior year included women (MSM&W) had lower frequencies of correct answers than participants with no women partners. Men with previous HIV testing experience and those who were HIV positive had higher HIV knowledge.

High prevalence of substance use among men who have sex with men in Buenos Aires, Argentina: implications for HIV risk behavior.

Five hundred gay and other men who have sex with men (G&MSM) from Buenos Aires, Argentina completed an assessment regarding substance use and sexual behavior. During the past 2 months, 78 % of participants consumed alcohol and 61 % drugs. Over 20 % of participants reporting alcohol, marijuana, cocaine sulfate, or tranquilizer use, did so daily.

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.

Background: The aim of this study was to estimate the prevalence of HIV and other STIs, among MSM from Buenos Aires (2007-2009).

Methods: Responding Driven Sampling was used for recruitment of MSM. Participants completed a structured web-based survey and provided biological samples.

Use of respondent driven sampling (RDS) generates a very diverse sample of men who have sex with men (MSM) in Buenos Aires, Argentina.

Background: 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.