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1.
Evol Ecol ; 34(3): 339-359, 2020.
Article in English | MEDLINE | ID: mdl-32508375

ABSTRACT

Mutations can occur throughout the virus genome and may be beneficial, neutral or deleterious. We are interested in mutations that yield a C next to a G, producing CpG sites. CpG sites are rare in eukaryotic and viral genomes. For the eukaryotes, it is thought that CpG sites are rare because they are prone to mutation when methylated. In viruses, we know less about why CpG sites are rare. A previous study in HIV suggested that CpG-creating transition mutations are more costly than similar non-CpG-creating mutations. To determine if this is the case in other viruses, we analyzed the allele frequencies of CpG-creating and non-CpG-creating mutations across various strains, subtypes, and genes of viruses using existing data obtained from Genbank, HIV Databases, and Virus Pathogen Resource. Our results suggest that CpG sites are indeed costly for most viruses. By understanding the cost of CpG sites, we can obtain further insights into the evolution and adaptation of viruses.

2.
J Virol ; 94(8)2020 03 31.
Article in English | MEDLINE | ID: mdl-31969438

ABSTRACT

As a long-acting formulation of the nonnucleoside reverse transcriptase inhibitor rilpivirine (RPV LA) has been proposed for use as preexposure prophylaxis (PrEP) and the prevalence of transmitted RPV-resistant viruses can be relatively high, we evaluated the efficacy of RPV LA to inhibit vaginal transmission of RPV-resistant HIV-1 in humanized mice. Vaginal challenges of wild-type (WT), Y181C, and Y181V HIV-1 were performed in mice left untreated or after RPV PrEP. Plasma viremia was measured for 7 to 10 weeks, and single-genome sequencing was performed on plasma HIV-1 RNA in mice infected during PrEP. RPV LA significantly prevented vaginal transmission of WT HIV-1 and Y181C HIV-1, which is 3-fold resistant to RPV. However, it did not prevent transmission of Y181V HIV-1, which has 30-fold RPV resistance in the viruses used for this study. RPV LA did delay WT HIV-1 dissemination in infected animals until genital and plasma RPV concentrations waned. Animals that became infected despite RPV LA PrEP did not acquire new RPV-resistant mutations above frequencies in untreated mice or untreated people living with HIV-1, and the mutations detected conferred low-level resistance. These data suggest that high, sustained concentrations of RPV were required to inhibit vaginal transmission of HIV-1 with little or no resistance to RPV but could not inhibit virus with high resistance. HIV-1 did not develop high-level or high-frequency RPV resistance in the majority of mice infected after RPV LA treatment. However, the impact of low-frequency RPV resistance on virologic outcome during subsequent antiretroviral therapy still is unclear.IMPORTANCE The antiretroviral drug rilpivirine was developed into a long-acting formulation (RPV LA) to improve adherence for preexposure prophylaxis (PrEP) to prevent HIV-1 transmission. A concern is that RPV LA will not inhibit transmission of drug-resistant HIV-1 and may select for drug-resistant virus. In female humanized mice, we found that RPV LA inhibited vaginal transmission of WT or 3-fold RPV-resistant HIV-1 but not virus with 30-fold RPV resistance. In animals that became infected despite RPV LA PrEP, WT HIV-1 dissemination was delayed until genital and plasma RPV concentrations waned. RPV resistance was detected at similar low frequencies in untreated and PrEP-treated mice that became infected. These results indicate the importance of maintaining RPV at a sustained threshold after virus exposure to prevent dissemination of HIV-1 after vaginal infection and low-frequency resistance mutations conferred low-level resistance, suggesting that RPV resistance is difficult to develop after HIV-1 infection during RPV LA PrEP.


Subject(s)
Anti-HIV Agents/pharmacology , HIV Infections/prevention & control , HIV Infections/transmission , HIV-1/drug effects , Pre-Exposure Prophylaxis/methods , Rilpivirine/pharmacology , Vagina/virology , Animals , Disease Models, Animal , Drug Resistance, Viral/drug effects , Female , HIV Infections/drug therapy , HIV-1/genetics , Mice , Mutation , Reverse Transcriptase Inhibitors/pharmacology , Virus Replication/drug effects , gag Gene Products, Human Immunodeficiency Virus/genetics
3.
Prev Chronic Dis ; 11: 130206, 2014 Jan 02.
Article in English | MEDLINE | ID: mdl-24384302

ABSTRACT

Community health assessment is a core function of public health departments, a standard for accreditation of public health departments, and a core competency for public health professionals. The Tennessee Department of Health developed a statewide initiative to improve the processes for engaging county health departments in assessing their community's health status through the collection and analysis of secondary data. One aim of the Tennessee Department of Health was to position county public health departments as trusted leaders in providing population data and engaging community stakeholders in assessments. The Tennessee Department of Health's Division of Policy, Planning, and Assessment conducted regional 2-day training workshops to explain and guide completion of computer spreadsheets on 12 health topics. Participants from 93 counties extracted data from multiple and diverse sources to quantify county demographics, health status, and resources and wrote problem statements based on the data examined. The workshops included additional staff development through integration of short lessons on data analysis, epidemiology, and social-behavior theory. Participants reported in post-workshop surveys higher degrees of comfort in interpreting data and writing about their findings on county health issues, and they shared their findings with health, hospital, school, and government leaders (including county health council members) in their counties. Completion of the assessments enabled counties and the Tennessee Department of Health to address performance-improvement goals and assist counties in preparing to meet public health accreditation prerequisites. The methods developed for using secondary data for community health assessment are Tennessee's first-phase response to counties' request for a statewide structure for conducting such assessments.


Subject(s)
Community Health Planning/organization & administration , Community Health Services/standards , Public Health Administration/methods , Delivery of Health Care/standards , Delivery of Health Care/statistics & numerical data , Humans , Local Government , Quality Improvement , Tennessee
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