21 research outputs found
Sexually transmitted infections among HIV serodiscordant partners: A secondary analysis of HIV Prevention Trial Network 052
Sexually transmitted infections (STIs) remain a public health concern because of their interaction(s) with HIV. In the HPTN 052 study, STIs were evaluated in both HIV-positive index cases and their HIV-negative partners at enrollment and at yearly follow-up visits. Our definition for STI was based on any infection with Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis, or Trichomonas vaginalis. We used log-binomial regression models to identify factors associated with prevalent STIs. Generalized estimating equation models with the Poisson distribution were used to compare STI incidence between HIV-positive index cases and HIV-negative partners. 8.1% of the participants had STIs at enrollment. The prevalence of STIs (8.9 vs. 7.2) was higher in HIV-positive index cases than HIV-negative partners. Being female (prevalence ratio (PR) = 1.61; 95% CI: 1.20â2.16) or unmarried (PR = 1.92; 95% CI: 1.17â3.14) was associated with prevalent STIs. Compared to HIV-negative male partners, HIV-positive female index cases had a higher risk of STI acquisition (incidence rate ratio (IRR) = 2.25; 95% CI: 1.70â2.97). While we are implementing HIV prevention interventions for HIV-negative people, we should also intensify targeted STI prevention interventions, especially among HIV-positive women
Pregnancy rates and clinical outcomes among women living with HIV enrolled in HPTN 052
HPTN 052 was a multi-country clinical trial of cART for preventing heterosexual HIV-1 transmission. The study allowed participation of pregnant women and provided access to cART and contraceptives. We explored associations between pregnancy and clinical measures of HIV disease stage and progression. Of 869 women followed for 5.70 (SD = 1.62) years, 94.7% were married/cohabitating, 96% initiated cART, and 76.3% had >2 past pregnancies. Of 337 women who experienced pregnancy, 89.3% were from countries with lower contraceptive coverage, 56.1% first started cART with PI-based regimens and 57.6% were 25â34 years old. Mean cART duration and condom use were similar among pregnant and nonpregnant individuals. Adjusting for confounders, viral load suppression (VLS) was not (aHR(CI) = 0.82(0.61, 1.08)) and CD4 was slightly associated with decreased rates of first pregnancy over time (aHR(CI) = 0.9(0.84, 0.95)); baseline VLS was associated with increased (aRR(CI) = 2.48(1.71, 3.59)) and baseline CD4 was slightly associated with decreased number of pregnancies (aRR(CI) = 0.9(0.85,0.96)) over study duration. Partner seroconversion was univariably associated with higher rates of first pregnancy (HR(CI) = 2.02(1.32,3.07)). Despite a background of higher maternal morbidity and mortality rates, our findings suggest that becoming pregnant does not pose a threat to maternal health in women with HIV when there is access to medical care and antiretroviral treatment
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
Virologic outcomes in early antiretroviral treatment: HPTN 052
Introduction: The HIV Prevention Trials Network (HPTN) 052 trial demonstrated that early antiretroviral therapy (ART) prevented 93% of HIV transmission events in serodiscordant couples. Some linked infections were observed shortly after ART initiation or after virologic failure. Objective: To evaluate factors associated with time to viral suppression and virologic failure in participants who initiated ART in HPTN 052. Methods: 1566 participants who had a viral load (VL) > 400 copies/mL at enrollment were included in the analyses. This included 832 in the early ART arm (CD4 350â550 cells/mm3 at ART initiation) and 734 in the delayed ART arm (204 with a CD4 < 250 cells/mm3 at ART initiation; 530 with any CD4 at ART initiation). Viral suppression was defined as two consecutive VLs †400 copies/mL after ART initiation; virologic failure was defined as two consecutive VLs > 1000 copies/mL > 24 weeks after ART initiation. Results: Overall, 93% of participants achieved viral suppression by 12 months. The annual incidence of virologic failure was 3.6%. Virologic outcomes were similar in the two study arms. Longer time to viral suppression was associated with younger age, higher VL at ART initiation, and region (Africa vs. Asia). Virologic failure was strongly associated with younger age, lower educational level, and lack of suppression by three months; lower VL and higher CD4 at ART initiation were also associated with virologic failure. Conclusions: Several clinical and demographic factors were identified that were associated with longer time to viral suppression and virologic failure. Recognition of these factors may help optimize ART for HIV treatment and prevention
HIV Drug Resistance in Adults Receiving Early vs. Delayed Antiretroviral Therapy: HPTN 052
Introduction: We evaluated HIV drug resistance in adults who received early vs. delayed antiretroviral therapy (ART) in a multinational trial [HIV Prevention Trials Network (HPTN) 052, enrollment 2005-2010]. In HPTN 052, 1763 index participants were randomized to start ART at a CD4 cell count of 350-550 cells/mm 3 (early ART arm) or 1000 copies/mL >24 weeks after ART initiation. Drug resistance testing was performed for pretreatment (baseline) and failure samples from participants with virologic failure. Results: HIV genotyping results were obtained for 211/249 participants (128 early ART arm and 83 delayed ART arm) with virologic failure. Drug resistance was detected in 4.7% of participants at baseline; 35.5% had new resistance at failure. In univariate analysis, the frequency of new resistance at failure was lower among participants in the early ART arm (compared with delayed ART arm, P = 0.06; compared with delayed ART arm with ART initiation before May 2011, P = 0.032). In multivariate analysis, higher baseline viral load (P = 0.0008) and ART regimen (efavirenz/lamivudine/zidovudine compared with other regimens, P = 0.024) were independently associated with higher risk of new resistance at failure. Conclusions: In HPTN 052, the frequency of new drug resistance at virologic failure was lower in adults with early ART initiation. The main factor associated with reduced drug resistance with early ART was lower baseline viral load
Brief Report: HIV Drug Resistance in Adults Failing Early Antiretroviral Treatment: Results from the HIV Prevention Trials Network 052 Trial
Early initiation of antiretroviral treatment (ART) reduces HIV transmission and has health benefits. HIV drug resistance can limit treatment options and compromise use of ART for HIV prevention. We evaluated drug resistance in 85 participants in the HIV Prevention Trials Network 052 trial who started ART at CD4 counts of 350-550 cells per cubic millimeter and failed ART by May 2011; 8.2% had baseline resistance and 35.3% had resistance at ART failure. High baseline viral load and less education were associated with emergence of resistance at ART failure. Resistance at ART failure was observed in 7 of 8 (87.5%) participants who started ART at lower CD4 cell counts
Total Cross Section in gamma gamma Collisions at LEP
The reaction e+e- -> e+e- gamma* gamma* -> e+e- hadrons for quasi-real
photons is studied using data from root(s) = 183 GeV up to 202 GeV.
Results on the total cross sections sigma(e+e- -> e+e- hadrons) and sigma(+e-
gamma* gamma* -> e+e- hadrons) are given for the two-photon centre-of-mass
energies 5 GeV < Wgammagamma < 185 GeV.
The total cross section of two real photons is described by a Regge
parametrisation. We observe a steeper rise with the two-photon centre-of-mass
energy as compared to the hadron-hadron and the photon-proton cross sections.
The data are also compared to the expectations of different theoretical models