The Y318F substitution in the 3' region of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) has been linked to nonnucleoside RT inhibitor (NNRTI) resistance in vitro. A systematic search of a large phenotypic-genotypic database (Virco) linked the Y318F substitution with a >10-fold decrease in NNRTI susceptibility in >85% of clinically derived isolates. There was a significant association between Y318F and use of delavirdine (P = 10(-11)) and nevirapine (P = 10(-6)) but not efavirenz (P = 0.3). Site-directed HIV-1 Y318F mutants in an HXB2 background displayed 42-fold-decreased susceptibility to delavirdine but <3-fold-decreased susceptibility to nevirapine or efavirenz. Combinations of Y318F with K103N, Y181C, or both resulted in decreased efavirenz susceptibility of 43-, 3.3-, and 84-fold, respectively, as well as >100- and >60-fold decreases in delavirdine and nevirapine susceptibility, respectively. These results indicate the importance of the Y318F substitution in HIV-1 drug resistance.
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http://dx.doi.org/10.1128/jvi.76.13.6836-6840.2002 | DOI Listing |
J Infect Dev Ctries
December 2024
Graduate Program in Health Sciences, Federal University of Sergipe, SE, Brazil.
Introduction: The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted public transportation systems worldwide. In this study, we evaluated the rate of COVID-19 positivity and its associated factors among users of public transportation in socioeconomically disadvantaged regions of Brazil during the pre-vaccination phase of the pandemic.
Methodology: This ecological study, conducted in Aracaju city in Northeast Brazil, is a component of the TestAju Program.
Nat Commun
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Sorbonne Université, CNRS, Laboratory of Computational and Quantitative Biology, LCQB, Paris, France.
Telomere shortening ultimately causes replicative senescence. However, identifying the mechanisms driving replicative senescence in cell populations is challenging due to the heterogeneity of telomere lengths and the asynchrony of senescence onset. Here, we present a mathematical model of telomere shortening and replicative senescence in Saccharomyces cerevisiae which is quantitatively calibrated and validated using data of telomerase-deficient single cells.
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Department of Integrative Biology, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India.
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View Article and Find Full Text PDFViruses
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Antiguo Hospital Civil de Guadalajara, "Fray Antonio Alcalde", Guadalajara 44280, Mexico.
This study investigates the relationship between SARS-CoV-2 RT-PCR cycle threshold (Ct) values and key COVID-19 transmission and outcome metrics across five years of the pandemic in Jalisco, Mexico. Utilizing a comprehensive time-series analysis, we evaluated weekly median Ct values as proxies for viral load and their temporal associations with positivity rates, reproduction numbers (Rt), hospitalizations, and mortality. Cross-correlation and lagged regression analyses revealed significant lead-lag relationships, with declining Ct values consistently preceding surges in positivity rates and hospitalizations, particularly during the early phases of the pandemic.
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January 2025
Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management, Yaoundé P.O. Box 3077, Cameroon.
Islatravir (ISL) is a novel antiretroviral that inhibits HIV-1 reverse transcriptase translocation. The M184V mutation, known to reduce ISL's viral susceptibility in vitro, could arise from prolonged exposure to nucleoside reverse transcriptase inhibitors (NRTI) (3TC). This study evaluated the predictive efficacy of ISL and identified potentially active antiretrovirals in combination among treatment-experienced patients in Cameroon, where NRTIs (3TC) have been the backbone of ART for decades now.
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