RICARDO DE PAULA VASCONCELOS

(Fonte: Lattes)
Índice h a partir de 2011
4
Projetos de Pesquisa
Unidades Organizacionais
LIM/52 - Laboratório de Virologia, Hospital das Clínicas, Faculdade de Medicina

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  • article 90 Citação(ões) na Scopus
    High pre-exposure prophylaxis uptake and early adherence among men who have sex with men and transgender women at risk for HIV Infection: the PrEP Brasil demonstration project
    (2017) HOAGLAND, Brenda; MOREIRA, Ronaldo I.; BONI, Raquel B. De; KALLAS, Esper G.; MADRUGA, Jose Valdez; VASCONCELOS, Ricardo; GOULART, Silvia; TORRES, Thiago S.; MARINS, Luana M. S.; ANDERSON, Peter L.; LUZ, Paula M.; LEITE, Iuri da Costa; LIU, Albert Y.; VELOSO, Valdilea G.; GRINSZTEJN, Beatriz
    Introduction: The efficacy of pre-exposure prophylaxis (PrEP) in preventing sexual acquisition of human immunodeficiency virus (HIV) is well established. Little is known about the feasibility of PrEP implementation in middle-income settings with concentrated epidemics among men who have sex with men (MSM) and transgender women (TGW). Methods: PrEP Brasil is a prospective, multicentre, open-label demonstration project assessing PrEP delivery in the context of the Brazilian Public Health System. HIV-uninfected MSM and TGW in 3 referral centres in Rio de Janeiro and Sao Paulo were evaluated for eligibility and offered 48 weeks of daily emtricitabine/tenofovir for PrEP. Concentrations of tenofovir diphosphate in dried blood spot samples (DBS) at week 4 after enrolment (early adherence) were measured. Predictors of drug levels were assessed using ordinal logistic regression models considering the DBS drug level as a 3 level variable (<350 fmol/punch, >= 350-699 fmol/punch and >= 700 fmol/punch). Results: 1,270 individuals were assessed for participation; n = 738 were potentially eligible and n = 450 were offered PrEP (PrEP uptake was 60.9%). Eligible but not enrolled individuals were younger, had lower HIV risk perception and had lower PrEP awareness. At week 4, 424 participants (of the 450 enrolled) had DBS TFV-DP concentrations, 94.1% in the protective range (>= 350 fmol/punch, consistent with >= 2 pills per week), and 78% were in the highly protective range (>= 700 fmol/punch, >= 4 pills per week). Participants with >= 12 years of schooling had 1.9 times the odds (95% CI 1.10-3.29) of a higher versus lower drug level than participants with <12 years of schooling. Condomless receptive anal intercourse in the prior 3 months was also associated with higher drug levels (adjusted OR = 1.78; 95% CI 1.08-2.94). Conclusions: The high uptake and early adherence indicate that PrEP for high-risk MSM and TGW can be successfully delivered in the context of the Brazilian Public Health System. Interventions to address disparities on PrEP awareness and HIV risk perception among the younger and less educated are urgently needed in order to maximize the impact of this prevention strategy on the reduction of HIV infection among MSM and TGW in Brazil.
  • article 7 Citação(ões) na Scopus
    Asymptomatic anorectal Chlamydia trachomatis and Neisseria gonorrhoeae infections are associated with systemic CD8(+) T-cell activation
    (2017) VIEIRA, Vinicius A.; AVELINO-SILVA, Vivian I.; CERQUEIRA, Natalia B.; COSTA, Dayane A.; COSTA, Priscilla R.; VASCONCELOS, Ricardo P.; MADRUGA, Valdez R.; MOREIRA, Ronaldo I.; HOAGLAND, Brenda; VELOSO, Valdilea G.; GRINSZTEJN, Beatriz; KALLAS, Esper G.
    Background: Oral preexposure prophylaxis (PrEP) has been established as a pivotal strategy in HIV prevention. However, bacterial sexually transmitted infections (STIs), such as Chlamydia trachomatis and Neisseria gonorrhoeae, are also highly prevalent. Although the presence of STI-related mucosal lesions is a known risk factor for HIV acquisition, the potential increase in risk associated with asymptomatic STIs is not completely understood. Recent data demonstrated higher T-cell activation is a risk factor for sexually acquired HIV-1 infection. We examined the effect of asymptomatic C. trachomatis and N. gonorrhoeae anorectal infection on systemic immune activation, potentially increasing the risk of HIV acquisition. Methods: We analyzed samples from participants of PrEP Brasil, a demonstration study of daily oral emtricitabine/tenofovir disoproxil fumarate HIV PrEP among healthy MSM, for T-cell activation by flow cytometry. We included 34 asymptomatic participants with anorectal swab for C. trachomatis and/or N. gonorrhoeae infection, whereas negative for other STIs, and 35 controls. Results: We found a higher frequency of human leukocyte antigen DR(+)CD3(+)CD8(+)T cells (1.5 vs. 0.9%, P<0.005) and with memory phenotype in the group with asymptomatic C. trachomatis and/or N. gonorrhoeae infection. Exhaustion and senescence markers were also significant higher in this group. No difference was observed in the soluble CD14 levels. Conclusion: Our findings suggest asymptomatic anorectal C. trachomatis and/or N. gonorrhoeae increase systemic immune activation, potentially increasing the risk of HIV acquisition. Regular screening and treatment of asymptomatic STIs should be explored as adjuvant tools for HIV prevention.