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1.
J Infect Dis ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38655842

RESUMEN

BACKGROUND: On-demand topical products could be an important tool for HIV prevention. We evaluated the safety, pharmacokinetics, and ex vivo pharmacodynamics of a tenofovir alafenamide/elvitegravir (TAF/EVG; 16 mg/20 mg) insert administered rectally. METHODS: MTN-039 was a Phase 1, open-label, single-arm, 2-dose study. Blood, rectal fluid (RF), and rectal tissue (RT) were collected over 72 hours (hr) following rectal administration of one and two TAF/EVG inserts for each participant. ClinicalTrials.gov Identifier: NCT04047420. RESULTS: TAF/EVG inserts were safe and well tolerated. EVG and tenofovir (TFV) were detected in blood plasma at low concentrations: median peak concentrations after 2 inserts were EVG 2.4 ng/mL and TFV 4.4 ng/mL. RT EVG peaked at 2-hr (median 2 inserts= 9 ng/mg) but declined to BLQ in the majority of samples at 24-hr, whereas TFV-DP remained high >2,000 fmol/million cells for 72-hr with 2 inserts. Compared to baseline, median cumulative log10 HIV p24 antigen of ex vivo rectal tissue HIV infection was reduced at each timepoint for both 1 and 2 inserts (p<0.065 and p<0.039, respectively). DISCUSSION: Rectal administration of TAF/EVG inserts achieved high rectal tissue concentrations of EVG and TFV-DP with low systemic drug exposure and demonstrable ex vivo inhibition of HIV infection for 72 hours.

2.
AIDS Behav ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740628

RESUMEN

The DESIRE Study (MTN-035) explored product preference among three placebo rectal microbicide (RM) formulations, a rectal douche (RD), a suppository, and an insert, among 210 sexually active transgender people and men who have sex with men in five counties: the United States, Peru, Thailand, South Africa, and Malawi. Participants used each product prior to receptive anal sex (RAS) for 1 month, following a randomly assigned sequence, then selected their preferred product via computer assisted self-interview. In-depth interviews examined reasons for preference. We compared product preference and prior product use by country to explore whether geographic location and experience with the similar products impacted preference. A majority in the United States (56%) and Peru (58%) and nearly half in South Africa (48%) preferred the douche. Most in Malawi (59%) preferred the suppository, while half in Thailand (50%) and nearly half in South Africa (47%) preferred the insert. Participants who preferred the douche described it as quick and easy, already routinized, and serving a dual purpose of cleansing and protecting. Those who preferred the insert found it small, portable, discreet, with quick dissolution. Those who preferred the suppository found the size and shape acceptable and liked the added lubrication it provided. Experience with product use varied by country. Participants with RD experience were significantly more likely to prefer the douche (p = 0.03). Diversifying availability of multiple RM dosage forms can increase uptake and improve HIV prevention efforts globally.


RESUMEN: El estudio DESIRE (MTN-035) exploró la preferencia de producto entre tres formulaciones de microbicida rectal (MR) de placebo, una ducha rectal, un supositorio y un inserto, entre 210 personas transgénero y hombres que tienen sexo con hombres en cinco países: los Estados Unidos, Perú., Tailandia, Sudáfrica y Malawi. Los participantes utilizaron cada producto antes del sexo anal receptive (SAR) durante un mes, siguiendo una secuencia asignada al azar, luego seleccionaron su producto preferido mediante una autoentrevista asistida por computadora. Las entrevistas en profundidad examinaron los motivos de preferencia. Comparamos la preferencia de producto y el uso previo del producto por país para explorar si la ubicación geográfica y la experiencia con la forma farmacéutica impactaron la preferencia. Una mayoría en los Estados Unidos (56%) y Perú (58%) y casi la mitad en Sudáfrica (48%) prefirieron la ducha rectal. La mayoría en Malawi (59%) prefirió el supositorio, mientras que la mitad en Tailandia (50%) y casi la mitad en Sudáfrica (47%) prefirió el inserto. Los participantes que prefirieron la ducha rectal la describieron como rápida y fácil, ya parte de su rutina y que tenía el doble propósito de limpiar y proteger. Los que prefirieron el inserto lo consideraron pequeño, portátil, discreto y de rápida disolución. Los que prefirieron el supositorio encontraron que tenía un tamaño y forma aceptables y proveía lubricación adicional. La experiencia con el uso del producto varió según el país. Los participantes con experiencia con duchas rectales tenían significativamente más probabilidades de preferir la ducha rectal (p = 0,03). Diversificar la disponibilidad de múltiples formas farmacéuticas de MR puede aumentar la aceptación y mejorar los esfuerzos de prevención del VIH a nivel mundial.

3.
BMC Public Health ; 23(1): 2464, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066471

RESUMEN

BACKGROUND: Rectal microbicides (RM) are biomedical HIV prevention products that aim to prevent or reduce the transmission of HIV and other sexually transmitted infections (STIs). RM modalities may be beneficial for populations who have complex lifestyles, difficulties adhering to pre-exposure prophylaxis (PrEP) regimens, and/or have limited access to care. MTN-035 (DESIRE; Developing and Evaluating Short-Acting Innovations for Rectal Use), a randomized crossover trial, aimed to evaluate the safety and acceptability of, and adherence to, three placebo RM modalities (douche, insert, and suppository) prior to receptive anal intercourse. METHODS: We conducted latent trajectory analysis to identify clusters of individuals who shared similar trajectories in acceptability and adherence for each product (douche, insert, and suppository) over time. We analyzed weekly short messaging service (SMS) use reports for each modality as reported by enrolled sexual and gender minority (SGM) participants. RESULTS: Two trajectories for each product were identified: a "protocol compliant" trajectory (i.e., at least one product use occasion per week) and "high use" trajectory (i.e., more than three product use occasions per week). Participants with high use were more likely to lack access to PrEP and have higher intentions to utilize RM modalities compared to those who were protocol compliant. CONCLUSIONS: This study highlighted high adherence to RM modalities among SGM. As research into viable HIV prevention modalities continues to evolve, tailored intervention strategies are needed to support the uptake of and adherence to alternative prevention modalities that are behaviorally congruent with targeted users. TRIAL REGISTRATION: NCT03671239 (14/09/2018).


Asunto(s)
Fármacos Anti-VIH , Antiinfecciosos , Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Humanos , Masculino , Infecciones por VIH/prevención & control , Estudios Cruzados , Conducta Sexual , Antiinfecciosos/uso terapéutico , Homosexualidad Masculina , Fármacos Anti-VIH/uso terapéutico
4.
Glob Chang Biol ; 28(1): 98-114, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34706120

RESUMEN

Dissolved organic carbon (DOC) and nitrogen (DON) are important energy and nutrient sources for aquatic ecosystems. In many northern temperate, freshwater systems DOC has increased in the past 50 years. Less is known about how changes in DOC may vary across latitudes, and whether changes in DON track those of DOC. Here, we present long-term DOC and DON data from 74 streams distributed across seven sites in biomes ranging from the tropics to northern boreal forests with varying histories of atmospheric acid deposition. For each stream, we examined the temporal trends of DOC and DON concentrations and DOC:DON molar ratios. While some sites displayed consistent positive or negative trends in stream DOC and DON concentrations, changes in direction or magnitude were inconsistent at regional or local scales. DON trends did not always track those of DOC, though DOC:DON ratios increased over time for ~30% of streams. Our results indicate that the dissolved organic matter (DOM) pool is experiencing fundamental changes due to the recovery from atmospheric acid deposition. Changes in DOC:DON stoichiometry point to a shifting energy-nutrient balance in many aquatic ecosystems. Sustained changes in the character of DOM can have major implications for stream metabolism, biogeochemical processes, food webs, and drinking water quality (including disinfection by-products). Understanding regional and global variation in DOC and DON concentrations is important for developing realistic models and watershed management protocols to effectively target mitigation efforts aimed at bringing DOM flux and nutrient enrichment under control.


Asunto(s)
Materia Orgánica Disuelta , Ríos , Carbono , Ecosistema , Nitrógeno/análisis
5.
AIDS Behav ; 26(5): 1333-1346, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34657218

RESUMEN

This study describes the acceptability of a rectal microbicide gel formulation using dapivirine (DPV) among men and women from two countries (United States and Thailand) participating in the Microbicide Trials Network-026 trial. We evaluated participants' acceptability of a rectal DPV/placebo gel as part of a Phase I trial (N = 26; 18 male, 8 female). Participants reported favorable acceptability of the study gel, with most participants reporting that they liked the gel the same (n = 14; 53.8%) or more (n = 11; 42.4%) than when they started the trial. Over half of participants noted that they would prefer the gel over condoms (n = 13; 50%) or that they liked condoms and the gel equally (n = 8; 30.8%). Side effects across products included leakage (n = 8; 30.8%), diarrhea (n = 4; 15.4%), or soiling (n = 1; 3.8%). The high acceptability of a rectal gel underscores its promise as a short-acting biomedical prevention, warranting future research for HIV prevention.Trial Registration: NCT03239483.


RESUMEN: Este estudio describe la aceptabilidad de un microbicida rectal (RM) con dapivirina (DPV) formulado como un gel por hombres y mujeres de dos países (Estados Unidos y Tailandia) que participaron como parte del Microbicide Trials Network (MTN)-026. Evaluamos la aceptabilidad de un gel rectal de DPV y un placebo como parte de un estudio de Fase I (N = 26; 18 hombres, 8 mujeres). Los participants informaron una aceptabilidad favorable sobre el gel del estudio; la mayoría de los participantes informaron que les gustó el gel igual (n = 14; 53.8%) o más (n = 11; 42.4%) que cuando comenzaron el estudio. Más de la mitad de los participantes señalaron que preferirían el gel sobre los condones (n = 13; 50%) o que les gustaban los condones y el gel por igual (n = 8; 30,8%). Los efectos de los productos incluyeron fugas (n = 8; 30,8%), diarrea (n = 4; 15,4%) o ensuciamiento (n = 1; 3,8%). La alta aceptabilidad de un gel rectal enfatiza su promesa para la prevención biomédica de acción corta y justifica futuras investigaciones para la prevención del VIH.


Asunto(s)
Antiinfecciosos , Infecciones por VIH , VIH-1 , Adulto , Antiinfecciosos/uso terapéutico , Femenino , Geles , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Masculino , Pirimidinas , Estados Unidos
6.
Clin Infect Dis ; 68(7): 1144-1151, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30289485

RESUMEN

BACKGROUND: Postmenopausal women have unique sociobiological human immunodeficiency virus (HIV) risks. We evaluated the safety, pharmacokinetics, and acceptability of a microbicide dapivirine (DPV) vaginal ring (VR) versus placebo in postmenopausal women. METHODS: We enrolled 96 HIV-negative postmenopausal US women in a phase 2a double-blind, randomized (3:1) trial of monthly VRs containing 25 mg DPV or placebo used continuously for 12 weeks. We assessed safety by adverse events (AEs). DPV concentrations were quantified in plasma and vaginal fluid. Steady-state concentrations were analyzed at 4, 8, and 12 weeks using repeated measures ANOVA. We assessed acceptability by self-report. RESULTS: We found no differences in the proportion of women with related grade 2 or higher reproductive system AEs (DPV: 6/72 (8%), placebo: 3/24 (13%), P = .68) or grade 3 or higher AEs (DPV: 4/72 (6%), placebo: 0/24 (0%), P = .57). In the DPV arm, 2/72 (3%) declined to resume product use due to AEs. Median DPV concentrations in plasma (262.0 pg/mL at week 12) and vaginal fluid (40.6 ng/mg at week 12) were constant over 12 weeks and exceeded the in vitro 50% effective concentration by 5000-fold in vaginal fluid by week 4. VR acceptability was high; 84/93 (90%) "very much liked or liked" the VR. CONCLUSIONS: DPV VRs were safe, well tolerated, and acceptable in postmenopausal women. Plasma concentrations were comparable to published data on DPV use in reproductive-age women (median plasma concentration: 264 pg/mL). Given the reassuring safety and pharmacokinetic data, the DPV VR is promising for preexposure prophylaxis in postmenopausal women. CLINICAL TRIALS REGISTRATION: NCT02010593.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/farmacocinética , Dispositivos Anticonceptivos Femeninos , Posmenopausia , Pirimidinas/efectos adversos , Pirimidinas/farmacocinética , Anciano , Fármacos Anti-VIH/administración & dosificación , Método Doble Ciego , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Aceptación de la Atención de Salud/estadística & datos numéricos , Placebos/administración & dosificación , Plasma/química , Pirimidinas/administración & dosificación , Estados Unidos
7.
Environ Sci Technol ; 52(4): 1971-1980, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29366328

RESUMEN

Land-use activities can alter hydrological and biogeochemical processes that can affect the fate, transformation, and transport of mercury (Hg). Previous studies in boreal forests have shown that forestry operations can have profound but variable effects on Hg export and methylmercury (MeHg) formation. The Pacific Northwest is an important timber producing region that receives large atmospheric Hg loads, but the impact of forest harvesting on Hg mobilization has not been directly studied and was the focus of our investigation. Stream discharge was measured continuously, and Hg and MeHg concentrations were measured monthly for 1.5 years following logging in three paired harvested and unharvested (control) catchments. There was no significant difference in particulate-bound Hg concentrations or loads in the harvested and unharvested catchments which may have resulted from forestry practices aimed at minimizing erosion. However, the harvested catchments had significantly higher discharge (32%), filtered Hg concentrations (28%), filtered Hg loads (80%), and dissolved organic carbon (DOC) loads (40%) compared to forested catchments. MeHg concentrations were low (mostly <0.05 ng L-1) in harvested, unharvested, and downstream samples due to well-drained/unsaturated soil conditions and steep slopes with high energy eroding stream channels that were not conducive to the development of anoxic conditions that support methylation. These results have important implications for the role forestry operations have in affecting catchment retention and export of Hg pollution.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Noroeste de Estados Unidos , Oregon , Movimientos del Agua
8.
Clin Infect Dis ; 64(5): 614-620, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-27986684

RESUMEN

Background: Human immunodeficiency virus (HIV) disproportionately affects men who have sex with men (MSM) and transgender women (TGW). Safe and acceptable topical HIV prevention methods that target the rectum are needed. Methods: MTN-017 was a phase 2, 3-period, randomized sequence, open-label, expanded safety and acceptability crossover study comparing rectally applied reduced-glycerin (RG) 1% tenofovir (TFV) and oral emtricitabine/TFV disoproxil fumarate (FTC/TDF). In each 8-week study period participants were randomized to RG-TFV rectal gel daily, or RG-TFV rectal gel before and after receptive anal intercourse (RAI; or at least twice weekly in the event of no RAI), or daily oral FTC/TDF. Results: MSM and TGW (n = 195) were enrolled from 8 sites in the United States, Thailand, Peru, and South Africa with mean age of 31.1 years (range 18-64). There were no differences in ≥grade 2 adverse event rates between daily gel (incidence rate ratio [IRR], 1.09; P = .59) or RAI gel (IRR, 0.90; P = .51) compared to FTC/TDF. High adherence (≥80% of prescribed doses assessed by unused product return and Short Message System reports) was less likely in the daily gel regimen (odds ratio [OR], 0.35; P < .001), and participants reported less likelihood of future daily gel use for HIV protection compared to FTC/TDF (OR, 0.38; P < .001). Conclusions: Rectal application of RG TFV gel was safe in MSM and TGW. Adherence and product use likelihood were similar for the intermittent gel and daily oral FTC/TDF regimens, but lower for the daily gel regimen. Clinical Trials Registration: NCT01687218.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Recto/efectos de los fármacos , Recto/virología , Inhibidores de la Transcriptasa Inversa/administración & dosificación , Tenofovir/administración & dosificación , Adolescente , Adulto , Terapia Antirretroviral Altamente Activa , Femenino , Geles , Glicerol , Infecciones por VIH/virología , VIH-1 , Homosexualidad Masculina , Humanos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Inhibidores de la Transcriptasa Inversa/efectos adversos , Tenofovir/efectos adversos , Resultado del Tratamiento , Adulto Joven
9.
Ecology ; 98(12): 3044-3055, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28881008

RESUMEN

Studies of trophic-level material and energy transfers are central to ecology. The use of isotopic tracers has now made it possible to measure trophic transfer efficiencies of important nutrients and to better understand how these materials move through food webs. We analyzed data from thirteen 15 N-ammonium tracer addition experiments to quantify N transfer from basal resources to animals in headwater streams with varying physical, chemical, and biological features. N transfer efficiencies from primary uptake compartments (PUCs; heterotrophic microorganisms and primary producers) to primary consumers was lower (mean 11.5%, range <1% to 43%) than N transfer efficiencies from primary consumers to predators (mean 80%, range 5% to >100%). Total N transferred (as a rate) was greater in streams with open compared to closed canopies and overall N transfer efficiency generally followed a similar pattern, although was not statistically significant. We used principal component analysis to condense a suite of site characteristics into two environmental components. Total N uptake rates among trophic levels were best predicted by the component that was correlated with latitude, DIN:SRP, GPP:ER, and percent canopy cover. N transfer efficiency did not respond consistently to environmental variables. Our results suggest that canopy cover influences N movement through stream food webs because light availability and primary production facilitate N transfer to higher trophic levels.


Asunto(s)
Cadena Alimentaria , Ciclo del Nitrógeno , Nitrógeno/análisis , Ríos/química , Animales , Nitrógeno/metabolismo , Isótopos de Nitrógeno
10.
Glob Chang Biol ; 23(8): 3064-3075, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28039909

RESUMEN

Streams and rivers are important conduits of terrestrially derived carbon (C) to atmospheric and marine reservoirs. Leaf litter breakdown rates are expected to increase as water temperatures rise in response to climate change. The magnitude of increase in breakdown rates is uncertain, given differences in litter quality and microbial and detritivore community responses to temperature, factors that can influence the apparent temperature sensitivity of breakdown and the relative proportion of C lost to the atmosphere vs. stored or transported downstream. Here, we synthesized 1025 records of litter breakdown in streams and rivers to quantify its temperature sensitivity, as measured by the activation energy (Ea , in eV). Temperature sensitivity of litter breakdown varied among twelve plant genera for which Ea could be calculated. Higher values of Ea were correlated with lower-quality litter, but these correlations were influenced by a single, N-fixing genus (Alnus). Ea values converged when genera were classified into three breakdown rate categories, potentially due to continual water availability in streams and rivers modulating the influence of leaf chemistry on breakdown. Across all data representing 85 plant genera, the Ea was 0.34 ± 0.04 eV, or approximately half the value (0.65 eV) predicted by metabolic theory. Our results indicate that average breakdown rates may increase by 5-21% with a 1-4 °C rise in water temperature, rather than a 10-45% increase expected, according to metabolic theory. Differential warming of tropical and temperate biomes could result in a similar proportional increase in breakdown rates, despite variation in Ea values for these regions (0.75 ± 0.13 eV and 0.27 ± 0.05 eV, respectively). The relative proportions of gaseous C loss and organic matter transport downstream should not change with rising temperature given that Ea values for breakdown mediated by microbes alone and microbes plus detritivores were similar at the global scale.


Asunto(s)
Carbono/química , Hojas de la Planta , Temperatura , Alnus , Cambio Climático , Ecosistema , Ríos
11.
Nature ; 452(7184): 202-5, 2008 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-18337819

RESUMEN

Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter groundwater and surface waters. Large-scale nitrogen budgets show that an average of about 20-25 per cent of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins, indicating that substantial sinks for nitrogen must exist in the landscape. Streams and rivers may themselves be important sinks for bioavailable nitrogen owing to their hydrological connections with terrestrial systems, high rates of biological activity, and streambed sediment environments that favour microbial denitrification. Here we present data from nitrogen stable isotope tracer experiments across 72 streams and 8 regions representing several biomes. We show that total biotic uptake and denitrification of nitrate increase with stream nitrate concentration, but that the efficiency of biotic uptake and denitrification declines as concentration increases, reducing the proportion of in-stream nitrate that is removed from transport. Our data suggest that the total uptake of nitrate is related to ecosystem photosynthesis and that denitrification is related to ecosystem respiration. In addition, we use a stream network model to demonstrate that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks.


Asunto(s)
Ecosistema , Actividades Humanas , Nitratos/análisis , Nitratos/metabolismo , Nitritos/análisis , Nitritos/metabolismo , Ríos/química , Agricultura , Bacterias/metabolismo , Simulación por Computador , Geografía , Nitrógeno/análisis , Nitrógeno/metabolismo , Isótopos de Nitrógeno , Plantas/metabolismo , Urbanización
12.
Proc Natl Acad Sci U S A ; 108(1): 214-9, 2011 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-21173258

RESUMEN

Nitrous oxide (N(2)O) is a potent greenhouse gas that contributes to climate change and stratospheric ozone destruction. Anthropogenic nitrogen (N) loading to river networks is a potentially important source of N(2)O via microbial denitrification that converts N to N(2)O and dinitrogen (N(2)). The fraction of denitrified N that escapes as N(2)O rather than N(2) (i.e., the N(2)O yield) is an important determinant of how much N(2)O is produced by river networks, but little is known about the N(2)O yield in flowing waters. Here, we present the results of whole-stream (15)N-tracer additions conducted in 72 headwater streams draining multiple land-use types across the United States. We found that stream denitrification produces N(2)O at rates that increase with stream water nitrate (NO(3)(-)) concentrations, but that <1% of denitrified N is converted to N(2)O. Unlike some previous studies, we found no relationship between the N(2)O yield and stream water NO(3)(-). We suggest that increased stream NO(3)(-) loading stimulates denitrification and concomitant N(2)O production, but does not increase the N(2)O yield. In our study, most streams were sources of N(2)O to the atmosphere and the highest emission rates were observed in streams draining urban basins. Using a global river network model, we estimate that microbial N transformations (e.g., denitrification and nitrification) convert at least 0.68 Tg·y(-1) of anthropogenic N inputs to N(2)O in river networks, equivalent to 10% of the global anthropogenic N(2)O emission rate. This estimate of stream and river N(2)O emissions is three times greater than estimated by the Intergovernmental Panel on Climate Change.


Asunto(s)
Desnitrificación/fisiología , Monitoreo del Ambiente/estadística & datos numéricos , Efecto Invernadero , Óxido Nitroso/metabolismo , Ríos/química , Monitoreo del Ambiente/métodos , Espectrometría de Masas , Modelos Teóricos , Isótopos de Nitrógeno/análisis , Estados Unidos
13.
J Int AIDS Soc ; 27(3): e26219, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38494656

RESUMEN

INTRODUCTION: End-user perspectives are vital to the design of new biomedical HIV prevention products. Conjoint analysis can support the integration of end-user perspectives by examining their preferences of potential pre-exposure prophylaxis (PrEP) products. The Microbicides Trial Network (MTN) 035 protocol examined three placebo rectal dosage forms (insert, enema and suppository) that could deliver PrEP prior to receptive anal sex (RAS). METHODS: Between April 2019 and July 2020, we enrolled 217 HIV-negative, cisgender men who have sex with men (MSM; n = 172; 79.3%) and transgender people (n = 47; 20.7%) ages 18-35 into a randomized cross-over trial across Malawi, Peru, South Africa, Thailand and the United States. Participants used each product prior to RAS over 4-week periods. Participants completed a conjoint experiment where they selected between random profiles using seven features (dosage form, timing of use before sex, side effects, duration of protection, effectiveness, frequency of use and need for a prescription). RESULTS: Effectiveness was the strongest determinant of choice (30.4%), followed by modality (18.0%), potential side effects (17.2%), frequency of use (10.8%), duration of protection (10.4%), timing of use before sex (7.4%) and need for a prescription (5.9%). Relative utility scores indicated that the most desirable combination of attributes was a product with 95% efficacy, used 30 minutes before sex, offering a 3- to 5-day protection window, used weekly, having no side effects, in the form of an enema and available over-the-counter. CONCLUSIONS: Choice in next-generation PrEP products is highly desired by MSM and transgender people, as no one-size-fits-all approach satisfies all the preferences. MTN-035 participants weighed product features differently, recognizing the need for diverse, behaviourally congruent biomedical options that fit the needs of intended end-users.


Asunto(s)
Antiinfecciosos , Infecciones por VIH , Minorías Sexuales y de Género , Humanos , Masculino , Antiinfecciosos/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Conducta Sexual , Estados Unidos , Femenino , Adolescente , Adulto Joven , Adulto
14.
PLoS One ; 19(6): e0304552, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38838028

RESUMEN

BACKGROUND: Vaginal rings formulated to deliver two drugs simultaneously have potential as user-controlled, long-acting methods for dual prevention of HIV and pregnancy. METHODS: Two phase 1 randomized trials (MTN-030/IPM 041 and MTN-044/IPM 053/CCN019) respectively enrolled 24 and 25 healthy, HIV-negative participants to evaluate safety, pharmacokinetics, and vaginal bleeding associated with use of a vaginal ring containing 200mg dapivirine (DPV) and 320mg levonorgestrel (LNG) designed for 90-day use. MTN-030/IPM 041 compared the DPV/LNG ring to a DPV-only ring (200mg) over 14 days of use. MTN-044/IPM 053/CCN019 compared continuous or cyclic use of the DPV/LNG ring over 90 days of use. Safety was assessed by recording adverse events (AEs). DPV and LNG concentrations were quantified in plasma, cervicovaginal fluid, and cervical tissue. Vaginal bleeding was self-reported. RESULTS: There were no differences in the proportion of participants with grade ≥2 genitourinary AEs or grade ≥3 AEs with DPV/LNG ring vs. DPV ring use (p = .22), or with DPV/LNG ring continuous vs. cyclic use (p = .67). Higher plasma DPV concentrations were observed in users of DPV/LNG compared to DPV-only rings (Cmax p = 0.049; AUC p = 0.091). Plasma DPV and LNG concentrations were comparable with continuous and cyclic use (Cmax p = 0.74; AUC p = 0.25). With cyclic use, median nadir plasma DPV concentration was approximately 300 pg/mL two days after removal and median t1/2 for cervicovaginal fluid DPV concentration was 5.76 hours (n = 3). Overall bleeding experiences did not differ between continuous and cyclic users (p = 0.12). CONCLUSIONS: The extended duration DPV/ LNG rings were well tolerated and the observed DPV concentrations in plasma and cervicovaginal fluid when used continuously exceeded concentrations observed in previous DPV ring efficacy studies. LNG concentrations in plasma were comparable with other efficacious LNG-based contraceptives. Genital DPV concentrations had a short half-life and were thus not well sustained following ring removal.


Asunto(s)
Dispositivos Anticonceptivos Femeninos , Levonorgestrel , Pirimidinas , Hemorragia Uterina , Humanos , Femenino , Levonorgestrel/farmacocinética , Levonorgestrel/administración & dosificación , Levonorgestrel/efectos adversos , Adulto , Pirimidinas/farmacocinética , Pirimidinas/efectos adversos , Pirimidinas/administración & dosificación , Dispositivos Anticonceptivos Femeninos/efectos adversos , Fármacos Anti-VIH/farmacocinética , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/administración & dosificación , Adulto Joven , Persona de Mediana Edad , Infecciones por VIH/tratamiento farmacológico
15.
PLoS One ; 18(4): e0284590, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37079602

RESUMEN

Disturbances to forested watersheds often result in increases of nutrients and light to nearby streams. Such changes are generally expected to produce a shift to a more autotrophic aquatic ecosystem, with measurable increases in algae, and associated implications for food webs and fisheries. Although this paradigm is widely established, results from our 10-year study (2007-2016) in 12 headwater streams and four sites downstream in the Trask River Watershed (Oregon, USA), did not concur. In 2012, one watershed was thinned, three were clearcut harvested with variable buffers and three with uniform riparian buffers. After harvest, light to the stream surface significantly increased at the three watersheds with variable buffers while dissolved inorganic nitrogen (DIN) significantly increased in all of the clearcut harvested streams. Despite the increase in DIN and light, algal standing stocks and chlorophyll a concentrations did not significantly increase. The common assumption of increased autotrophic responses in stream food webs following increases of nitrogen and light was not supported here. We postulate the co-limitation of nutrients, driven by low phosphorus concentrations, which unlike DIN did not increase post-harvest, and the characteristics of the algal community, which were dominated by low light adapted diatoms rather than green algae, contributed to our findings of no responses for standing stocks of epilithic algae or concentrations of chlorophyll a. The inclusion of multiple statistical analyses provided more certainty around our findings. This study documents responses to current forest practices and provides cautionary information for management and restoration activities aiming to increase fish abundance and standing stocks by opening riparian canopies and adding nutrients.


Asunto(s)
Ecosistema , Nitratos , Animales , Nitratos/análisis , Clorofila A , Compuestos Orgánicos , Bosques , Nitrógeno/análisis
16.
PLoS One ; 18(4): e0284339, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37043527

RESUMEN

Efforts to develop a range of HIV prevention products that can serve as behaviorally congruent viable alternatives to consistent condom use and oral pre-exposure prophylaxis (PrEP) remain crucial. MTN-035 was a randomized crossover trial seeking to evaluate the safety, acceptability, and adherence to three placebo modalities (insert, suppository, enema) prior to receptive anal intercourse (RAI). If participants had no RAI in a week, they were asked to use their assigned product without sex. We hypothesized that the modalities would be acceptable and safe for use prior to RAI, and that participants would report high adherence given their behavioral congruence with cleansing practices (e.g., douches and/or enemas) and their existing use to deliver medications (e.g., suppositories; fast-dissolving inserts) via the rectum. Participants (N = 217) were sexual and gender minorities enrolled in five different countries (Malawi, Peru, South Africa, Thailand, and the United States of America). Mean age was 24.9 years (range 18-35 years). 204 adverse events were reported by 98 participants (45.2%); 37 (18.1%) were deemed related to the study products. The proportion of participants reporting "high acceptability" was 72% (95%CI: 65% - 78%) for inserts, 66% (95%CI: 59% - 73%) for suppositories, and 73% (95%CI: 66% - 79%) for enemas. The proportion of participants reporting fully adherent per protocol (i.e., at least one use per week) was 75% (95%CI: 69% - 81%) for inserts, 74% (95%CI: 68% - 80%) for suppositories, and 83% (95%CI: 77% - 88%) for enemas. Participants fully adherent per RAI-act was similar among the three products: insert (n = 99; 58.9%), suppository (n = 101; 58.0%) and enema (n = 107; 58.8%). The efficacy and effectiveness of emerging HIV prevention drug depends on safe and acceptable delivery modalities that are easy to use consistently. Our findings demonstrate the safety and acceptability of, and adherence to, enemas, inserts, and suppositories as potential modalities through which to deliver a rectal microbicide.


Asunto(s)
Antiinfecciosos , Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Masculino , Humanos , Adolescente , Adulto Joven , Adulto , Recto , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Homosexualidad Masculina , Supositorios , Conducta Sexual , Antiinfecciosos/uso terapéutico
17.
Lancet HIV ; 10(12): e779-e789, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37898146

RESUMEN

BACKGROUND: Half of new HIV acquisitions in Africa occur in adolescent girls and young women. Pre-exposure prophylaxis (PrEP) with oral tenofovir disoproxil fumarate plus emtricitabine or the monthly dapivirine vaginal ring is efficacious but has lower adherence and effectiveness among adolescent girls and young women. We aimed to assess product adherence, safety, and choice of oral PrEP compared with the dapivirine ring among African adolescent girls and young women. METHODS: MTN-034/REACH was a randomised, open-label, phase 2a crossover trial among HIV-seronegative, non-pregnant adolescent girls and young women aged 16-21 years at four clinical research sites in South Africa, Uganda, and Zimbabwe. Participants were randomly assigned (1:1) to either the dapivirine ring or daily oral PrEP (200 mg of emtricitabine and 300 mg of tenofovir disoproxil fumarate) for 6 months, then switched to the other product option for 6 months, followed by a third 6-month period in which participants were given a choice of oral PrEP, the dapivirine ring, or neither. Fixed block randomisation was used, stratified by site. The primary adherence endpoint was use of each product during the randomised periods, with high use defined as tenofovir-diphosphate concentrations greater than or equal to 700 fmol/punch (associated with taking an average of four or more tablets per week in the previous month) and greater than or equal to 4 mg dapivirine released from the returned ring (continuous use for 28 days in the previous month) based on residual drug concentrations. The primary safety endpoint was grade 2 or higher adverse events during each randomised period of 24 weeks of ring and oral PrEP. This trial is registered at ClinicalTrials.gov, NCT03593655. FINDINGS: From Feb 6, 2019 to Sept 9, 2021, 396 adolescent girls and young women were screened, 247 of whom were enrolled and randomly assigned (6 months of the ring followed by 6 months of oral PrEP n=124; 6 months of oral PrEP followed by 6 months of the ring n=123). Median age was 18 years (IQR 17-19). 54 grade 2 or higher product-related adverse events were reported during oral PrEP and five during dapivirine ring use, with no product-related serious adverse events. High adherence was observed in 753 (57%) of the 1316 oral PrEP visits and 806 (57%) of the 1407 dapivirine ring visits. Four women acquired HIV during follow-up. INTERPRETATION: Adherence was moderately high and similar between oral PrEP and the dapivirine ring with favourable safety and tolerability. Oral PrEP and the dapivirine ring are effective, safe, and well tolerated HIV prevention options for adolescent girls and young women who would benefit from a choice of PrEP formulations to meet their needs and preferences. FUNDING: National Institutes of Health.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Humanos , Femenino , Adolescente , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Estudios Cruzados , Tenofovir/uso terapéutico , Emtricitabina/efectos adversos , Inhibidores de la Transcriptasa Inversa/efectos adversos , Sudáfrica/epidemiología
18.
Violence Vict ; 27(4): 609-31, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22978078

RESUMEN

Despite growing awareness of crime victims' needs for support and services, few studies have examined the training needs of those who provide such services. This research presents the results of statewide needs assessment of victims services providers (VSPs) conducted in preparation for designing a state victim assistance training academy. Respondents were asked to indicate their needs for training on various topics pertaining to victims services. Results indicate that extent of formal education and years of experience in the field are the primary determinants of reported needs for training. Respondents with less formal education and less experience in the field, regardless of the nature of their organizational position (client services vs. management), report greater needs for training. Implications for designing training programs for VSPs are discussed.


Asunto(s)
Servicios de Salud Comunitaria/organización & administración , Intervención en la Crisis (Psiquiatría)/educación , Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Capacitación en Servicio/métodos , Servicio Social/educación , Maltrato Conyugal/prevención & control , Adulto , Terapia Cognitivo-Conductual/educación , Consejo/educación , Víctimas de Crimen/estadística & datos numéricos , Femenino , Humanos , Comunicación Interdisciplinaria , Masculino , Persona de Mediana Edad , Servicio Social/organización & administración , Virginia/epidemiología
19.
Sci Rep ; 12(1): 20266, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36456610

RESUMEN

Predicting the edges of species distributions is fundamental for species conservation, ecosystem services, and management decisions. In North America, the location of the upstream limit of fish in forested streams receives special attention, because fish-bearing portions of streams have more protections during forest management activities than fishless portions. We present a novel model development and evaluation framework, wherein we compare 26 models to predict upper distribution limits of trout in streams. The models used machine learning, logistic regression, and a sophisticated nested spatial cross-validation routine to evaluate predictive performance while accounting for spatial autocorrelation. The model resulting in the best predictive performance, termed UPstream Regional LiDAR Model for Extent of Trout (UPRLIMET), is a two-stage model that uses a logistic regression algorithm calibrated to observations of Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii) occurrence and variables representing hydro-topographic characteristics of the landscape. We predict trout presence along reaches throughout a stream network, and include a stopping rule to identify a discrete upper limit point above which all stream reaches are classified as fishless. Although there is no simple explanation for the upper distribution limit identified in UPRLIMET, four factors, including upstream channel length above the point of uppermost fish, drainage area, slope, and elevation, had highest importance. Across our study region of western Oregon, we found that more of the fish-bearing network is on private lands than on state, US Bureau of Land Mangement (BLM), or USDA Forest Service (USFS) lands, highlighting the importance of using spatially consistent maps across a region and working across land ownerships. Our research underscores the value of using occurrence data to develop simple, but powerful, prediction tools to capture complex ecological processes that contribute to distribution limits of species.


Asunto(s)
Oncorhynchus , Trucha , Animales , Ríos , Ecosistema , Alimentos Marinos
20.
AIDS Patient Care STDS ; 36(3): 97-105, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35289688

RESUMEN

For women in the United States who remain sexually active beyond child-bearing years, susceptibility to HIV infection remains, yet condom use is low. We assessed acceptability of the dapivirine vaginal ring (ring) among 96 postmenopausal US women enrolled in a placebo-controlled multisite phase II trial of the ring, using questionnaires and in-depth interviews. Three quarters of women reported "perfect" adherence (ring never out) over the 3-month trial period. At study exit, the ring was found to be very easy to use by 72%, very comfortable to wear by 65%, and 4% reported it ever interfered with their daily activities. The most common worries among participants at preinitiation had decreased significantly at study exit (e.g., worries about inserting the ring declined from 46% to 6%, discomfort during daily activities from 53% to 3%, ring not staying in place from 48% to 14%, all p < 0.0001). Despite some couples feeling the ring during sex, the ring was perceived as more suitable than condoms for prevention because it was not burdensome to use, did not interfere with erection, and provided (for some) additional vaginal lubrication. The ring is a promising, highly acceptable HIV prevention method that is suitable to the lives of postmenopausal women and their male partners and can provide them with an additional prevention choice. Clinical Trials Registration: NCT02010593.


Asunto(s)
Fármacos Anti-VIH , Dispositivos Anticonceptivos Femeninos , Infecciones por VIH , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Masculino , Posmenopausia , Pirimidinas
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