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Clinical trial registrationClinical Trials.gov NCT00131677.

BackgroundCryopreservation of leukocytes isolated from the cervicovaginal and colorectal mucosa is useful for the study of cellular immunity (see Hughes SM et al. PLOS ONE 2016). However, some questions about mucosal biology and sexually transmitted infections are better addressed with intact mucosal tissue, for which there is no standard cryopreservation protocol.Methods and findingsTo find an optimal preservation protocol for mucosal tissues, we tested slow cooling (1°C/min) with 10% dimethylsulfoxide (designated "cryopreservation") and fast cooling (plunge in liquid nitrogen) with 20% dimethylsulfoxide and 20% ethylene glycol ("vitrification"). We compared fresh and preserved human cervicovaginal and colorectal tissues in a range of assays, including metabolic activity, human immunodeficiency virus infection, cell phenotype, tissue structure by hematoxylin-and-eosin staining, cell number and viability, production of cytokines, and microbicide drug concentrations. Metabolic activity, HIV infectability, and tissue structure were similar in cryopreserved and vitrified vaginal tissues. However, vitrification led to poor cell recovery from the colorectal mucosa, with 90% fewer cells recovered after isolation from vitrified colorectal tissues than from cryopreserved. HIV infection rates were similar for fresh and cryopreserved ectocervical tissues, whereas cryopreserved colorectal tissues were less easily infected than fresh tissues (hazard ratio 0.7 [95% confidence interval 0.4, 1.2]). Finally, we compared isolation of cells before and after cryopreservation. Cell recoveries were higher when cells were isolated after freezing and thawing (71% [59-84%]) than before (50% [38-62%]). Cellular function was similar to fresh tissue in both cases. Microbicide drug concentrations were lower in cryopreserved explants compared to fresh ones.ConclusionsCryopreservation of intact cervicovaginal and colorectal tissues with dimethylsulfoxide works well in a range of assays, while the utility of vitrification is more limited. Cell yields are higher from cryopreserved intact tissue pieces than from thawed cryopreserved single cell suspensions isolated before freezing, but T cell functions are similar.

BackgroundPre-exposure prophylaxis (PrEP) trials using tenofovir-based regimens have demonstrated that high levels of adherence are required to evaluate efficacy; the incorporation of objective biomarkers of adherence in trial design has been essential to interpretation, given the inaccuracy of self-report. Antiretroviral measurements in scalp hair have been useful as a marker of long-term exposure in the HIV treatment setting, and hair samples are relatively easy and inexpensive to collect, transport, and store for analysis. To evaluate the relationship between dose and tenofovir concentrations in hair, we examined the dose proportionality of tenofovir in hair in healthy, HIV-uninfected adults.MethodsA phase I, crossover pharmacokinetic study was performed in 24 HIV-negative adults receiving directly-observed oral tenofovir tablets administered 2, 4, and 7 doses/week for 6 weeks, with a ≥3-week break between periods. Small samples of hair were collected after each six-week period and analyzed for tenofovir concentrations. Geometric-mean-ratios compared levels between each pair of dosing conditions. Intensive plasma pharmacokinetic studies were performed during the daily-dosing period to calculate areas-under-the-time-concentration curves (AUCs).ResultsOver 90% of doses were observed per protocol. Median tenofovir concentrations in hair increased monotonically with dose. A log-linear relationship was seen between dose and hair levels, with an estimated 76% (95% CI 60-93%) increase in hair level per 2-fold dose increase. Tenofovir plasma AUCs modestly predicted drug concentrations in hair.ConclusionsThis study found a strong linear relationship between frequency of dosing and tenofovir levels in scalp hair. The analysis of quantitative drug levels in hair has the potential to improve adherence measurement in the PrEP field and may be helpful in determining exposure thresholds for protection and explaining failures in PrEP trials. Hair measures for adherence monitoring may also facilitate adherence measurement in real-world settings and merit further investigation in upcoming PrEP implementation studies and programs.Trial registrationClinicalTrials.gov NCT00903084.

Background: African adolescent girls and young women (AGYW) represent a large proportion of new HIV infections, a priority population for pre-exposure prophylaxis (PrEP), but adherence remains a challenge. A reliable, valid readiness tool would help identify AGYW motivated to take PrEP who need adherence support. Methods: In the HPTN 082 open-label PrEP study (2016–2019), South African and Zimbabwean women ages 16–25 were administered an HIV prevention readiness measure (HPRM). The 25 items in the HPRM included medication beliefs, connection with care, disclosure of PrEP use, social support, and housing stability using a 5-point Likert scale. Exploratory factor analysis (EFA) using polychoric correlations, scale reliability, and predictive validity were performed on data from 315 participants who responded to all items. We assessed the predictive value of HPRM scores with PrEP adherence, defined as tenofovir-diphosphate (TFV-DP) concentrations in dried blood spots, as a continuous measure and dichotomized as high PrEP adherence (≥700 fmol/punch). Results: EFA yielded 23 items with three subscales: self-efficacy (16 items), PrEP disclosure (4 items), and social support (3 items). Cronbach's α ranged from 0.71 to 0.92 for the overall scale and the subscales. The average overall scale and the subscales were predictive of 3-month PrEP adherence for TFV-DP concentrations: for each unit increase of the HPRM score, TFV-DP concentration increased by 103 fmol/punch (95% CI: 16, 189, p = 0.02); the highest HPRM score equated with 608 fmol/punch on average. For the self-efficacy subscale, TFV-DP increased by 90 fmol/punch (95% CI: 7, 172, p = 0.03); PrEP disclosure, 68 fmol/punch (95% CI: 19, 117 p = 0.01); and social support, 58fmol/punch (95% CI: 2, 113, p = 0.04). Higher PrEP disclosure suggests high adherence (OR 1.36, 95% CI: 1.00, 1.86, p = 0.05) and predicted persistent high adherence at both months three and six (OR: 1.50, 95% CI: 1.03, 2.21, p = 0.04). Conclusions: The HPRM scale overall and the subscales individually demonstrated good internal consistency among African young women. PrEP disclosure subscale exhibiting significant association with persistent high PrEP adherence is an important finding for PrEP adherence support programs. Future work will assess replicability and expand self-efficacy and social-support subscales after item revision. Trial registration: ClinicalTrials.gov NCT02732730. [ABSTRACT FROM AUTHOR]

Introduction: Implementation of evidence-based care for heavy drinking and depression remains low in global health systems. We tested the impact of providing community support, training, and clinical packages of varied intensity on depression screening and management for heavy drinking patients in Latin American primary healthcare. Materials and methods: Quasi-experimental study involving 58 primary healthcare units in Colombia, Mexico and Peru randomized to receive: (1) usual care (control); (2) training using a brief clinical package; (3) community support plus training using a brief clinical package; (4) community support plus training using a standard clinical package. Outcomes were proportion of: (1) heavy drinking patients screened for depression; (2) screen-positive patients receiving appropriate support; (3) all consulting patients screened for depression, irrespective of drinking status. Results: 550/615 identified heavy drinkers were screened for depression (89.4%). 147/230 patients screening positive for depression received appropriate support (64%). Amongst identified heavy drinkers, adjusting for country, sex, age and provider profession, provision of community support and training had no impact on depression activity rates. Intensity of clinical package also did not affect delivery rates, with comparable performance for brief and standard versions. However, amongst all consulting patients, training providers resulted in significantly higher rates of alcohol measurement and in turn higher depression screening rates; 2.7 times higher compared to those not trained. Conclusions: Training using a brief clinical package increased depression screening rates in Latin American primary healthcare. It is not possible to determine the effectiveness of community support on depression activity rates due to the impact of COVID-19. [ABSTRACT FROM AUTHOR]

Background: Adolescents born extremely preterm (EP; <28 weeks' gestation) and/or extremely low birthweight (ELBW; <1000 g) experience high rates of visual impairments, however the potential neural correlates of visual impairments in EP/ELBW adolescents require further investigation. This study aimed to: 1) compare optic radiation and primary visual cortical structure between EP/ELBW adolescents and normal birthweight controls; 2) investigate associations between perinatal factors and optic radiation and primary visual cortical structure in EP/ELBW adolescents; 3) investigate associations between optic radiation and primary visual cortical structure in EP/ELBW adolescents and the odds of impaired vision. Methods: 196 EP/ELBW adolescents and 143 controls underwent magnetic resonance imaging at a mean age of 18 years. Optic radiations were delineated using constrained spherical deconvolution based probabilistic tractography. Primary visual cortices were segmented using FreeSurfer software. Diffusion tensor variables and tract volume of the optic radiations, as well as volume, surface area and thickness of the primary visual cortices, were estimated. Results: Axial, radial and mean diffusivities within the optic radiations, and primary visual cortical thickness, were higher in the EP/ELBW adolescents than controls. Within EP/ELBW adolescents, postnatal corticosteroid exposure was associated with altered optic radiation diffusion values and lower tract volume, while decreasing gestational age at birth was associated with increased primary visual cortical volume, area and thickness. Furthermore, decreasing optic radiation fractional anisotropy and tract volume, and increasing optic radiation diffusivity in EP/ELBW adolescents were associated with increased odds of impaired vision, whereas primary visual cortical measures were not associated with the odds of impaired vision. Conclusions: Optic radiation and primary visual cortical structure are altered in EP/ELBW adolescents compared with controls, with the greatest alterations seen in those exposed to postnatal corticosteroids and those born earliest. Structural alterations to the optic radiations may increase the risk of impaired vision in EP/ELBW adolescents. [ABSTRACT FROM AUTHOR]