Myron S. Cohen

Bio: Myron S. Cohen is an academic researcher from University of North Carolina at Chapel Hill. The author has contributed to research in topics: Population & Acquired immunodeficiency syndrome (AIDS). The author has an hindex of 103, co-authored 549 publications receiving 46021 citations. Previous affiliations of Myron S. Cohen include University of Massachusetts Medical School & Scripps Health.

Single and Multiple Dose Pharmacokinetics of Maraviroc in Saliva, Semen, and Rectal Tissue of Healthy HIV-Negative Men

Abstract: Between 2004 and 2007, the incidence of HIV/AIDS increased 15% in the United States [1]. In men who have sex with men (MSM), this increase was 26%. The highest risk of HIV acquisition occurs with receptive anal intercourse [2], as the rectal mucosa is rich in lymphoid tissue and has a thin epithelium [3]. Data from the Phase III CAPRISA 004 study, which evaluated a topical tenofovir gel formulation for prevention of HIV acquisition in women, not only provide the proof of concept for microbicides but also further evidence that antiretroviral-based prevention strategies can be effective [4]. To date, topical rectal microbicide and vaccine trials have not demonstrated compelling benefit in HIV prevention; therefore, investigations using orally administered antiretrovirals are still necessary [5, 6]. Antiretrovirals can be used for both primary and secondary HIV prevention. Primary prophylaxis prevents acquisition of HIV in an uninfected individual, and secondary prophylaxis reduces the likelihood of an HIV-infected individual transmitting HIV. Primary prevention can be further separated into pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP). PrEP requires administering antiretrovirals to at-risk individuals prior to a potential HIV exposure, and PEP involves administering antiretrovirals to an HIV-negative individual after a suspected exposure to HIV. Measuring antiretroviral exposure in rectal tissue could assist in selecting drugs and dosing regimens for PrEP and PEP. HIV transmission modeling has correlated increasing concentrations of HIV RNA in semen to an increasing probability of infection [7]. Despite suppression of HIV RNA in blood, HIV RNA can still be detected in genital secretions of up to 8% of HIV-infected men on antiretroviral therapy [8]. Using selected antiretrovirals to target the genital tract and decrease HIV replication in genital secretions has implications for transmission. If semen drug concentrations are high enough, it might be also be possible to deliver a protective amount of drug to a receptive mucosal surface through this route [9]. The ability to monitor drug concentrations has allowed clinicians to make important decisions regarding adherence to antiretroviral regimens. Under most conditions, concentration monitoring requires a blood sample. Saliva sampling has been explored as an alternative to blood sampling and has the advantages of being less invasive and requiring less processing time upon collection [10]. Within the female genital tract, the CCR5 antagonist maraviroc (Celsentri/Selzentry; Pfizer, Inc) achieves very high exposure [11]. The current study was designed to understand exposure of maraviroc in the saliva, seminal fluid, and rectal tissue following single and multiple doses.

Clinical Endpoints for Evaluating Efficacy in COVID-19 Vaccine Trials.

Abstract: Several vaccine candidates to protect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or coronavirus disease 2019 (COVID-19) have entered or will soon enter large-scale, phase 3, placebo-controlled randomized clinical trials. To facilitate harmonized evaluation and comparison of the efficacy of these vaccines, a general set of clinical endpoints is proposed, along with considerations to guide the selection of the primary endpoints on the basis of clinical and statistical reasoning. The plausibility that vaccine protection against symptomatic COVID-19 could be accompanied by a shift toward more SARS-CoV-2 infections that are asymptomatic is highlighted, as well as the potential implications of such a shift.

Prevalence of HIV Infection Among Young Adults in the United States: Results From the Add Health Study

Abstract: Objectives. We estimated HIV prevalence rates among young adults in the United States.Methods. We used survey data from the third wave of the National Longitudinal Study of Adolescent Health, a random sample of nearly 19000 young adults initiated in 1994–1995. Consenting respondents were screened for the presence of antibodies to HIV-1 in oral mucosal transudate specimens. We calculated prevalence rates, accounting for survey design, response rates, and test performance.Results. Among the 13184 participants, the HIV prevalence rate was 1.0 per 1000 (95% confidence interval [CI] = 0.4, 1.7). Gender-specific prevalence rates were similar, but rates differed markedly between non-Hispanic Blacks (4.9 per 1000; 95% CI=1.8, 8.7) and members of other racial/ethnic groups (0.22 per 1000; 95% CI=0.00, 0.64).Conclusions. Racial disparities in HIV in the United States are established early in the life span, and our data suggest that 15% to 30% of all cases of HIV occur among individuals younger than 25 years.

HIV-1 treatment as prevention: the good, the bad, and the challenges

Abstract: Purpose of review This work focuses on the use of antiretroviral agents to prevent the sexual transmission of HIV-1. Recent findings Two randomized clinical trials demonstrated that antiretroviral agents provided before exposure to HIV-1 offer substantial protection, ostensibly directly proportional to the concentration of antiretroviral therapy (ART) in the genital secretions. Intense focus on the use of HIV treatment as prevention has led to publication of modeling exercises, ecological studies, and observational studies, most of which support the potential benefits of ART. However, the logistical requirements for successful use of ART for prevention are considerable. Summary ART will serve as a cornerstone of combination prevention of HIV-1. Continued research will be essential to measure anticipated benefits and to detect implementation barriers and untoward consequences of such a program, especially increases in primary ART resistance.

Prevention of HIV-1 Infection with Early Antiretroviral Therapy

Abstract: Background Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. Methods In nine countries, we...

Infectious Diseases Society of America/American Thoracic Society Consensus Guidelines on the Management of Community-Acquired Pneumonia in Adults

Abstract: Lionel A. Mandell, Richard G. Wunderink, Antonio Anzueto, John G. Bartlett, G. Douglas Campbell, Nathan C. Dean, Scott F. Dowell, Thomas M. File, Jr. Daniel M. Musher, Michael S. Niederman, Antonio Torres, and Cynthia G. Whitney McMaster University Medical School, Hamilton, Ontario, Canada; Northwestern University Feinberg School of Medicine, Chicago, Illinois; University of Texas Health Science Center and South Texas Veterans Health Care System, San Antonio, and Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Houston, Texas; Johns Hopkins University School of Medicine, Baltimore, Maryland; Division of Pulmonary, Critical Care, and Sleep Medicine, University of Mississippi School of Medicine, Jackson; Division of Pulmonary and Critical Care Medicine, LDS Hospital, and University of Utah, Salt Lake City, Utah; Centers for Disease Control and Prevention, Atlanta, Georgia; Northeastern Ohio Universities College of Medicine, Rootstown, and Summa Health System, Akron, Ohio; State University of New York at Stony Brook, Stony Brook, and Department of Medicine, Winthrop University Hospital, Mineola, New York; and Cap de Servei de Pneumologia i Allergia Respiratoria, Institut Clinic del Torax, Hospital Clinic de Barcelona, Facultat de Medicina, Universitat de Barcelona, Institut d’Investigacions Biomediques August Pi i Sunyer, CIBER CB06/06/0028, Barcelona, Spain.

Role of free radicals and catalytic metal ions in human disease: an overview.

Abstract: Publisher Summary This chapter discusses the role of free radicals and catalytic metal ions in human disease. The importance of transition metal ions in mediating oxidant damage naturally leads to the question as to what forms of such ions might be available to catalyze radical reactions in vivo . The chapter discusses the metabolism of transition metals, such as iron and copper. It also discusses the chelation therapy that is an approach to site-specific antioxidant protection. The detection and measurement of lipid peroxidation is the evidence most frequently cited to support the involvement of free radical reactions in toxicology and in human disease. A wide range of techniques is available to measure the rate of this process, but none is applicable to all circumstances. The two most popular are the measurement of diene conjugation and the thiobarbituric acid (TBA) test, but they are both subject to pitfalls, especially when applied to human samples. The chapter also discusses the essential principles of the peroxidation process. When discussing lipid peroxidation, it is essential to use clear terminology for the sequence of events involved; an imprecise use of terms such as initiation has caused considerable confusion in the literature. In a completely peroxide-free lipid system, first chain initiation of a peroxidation sequence in a membrane or polyunsaturated fatty acid refers to the attack of any species that has sufficient reactivity to abstract a hydrogen atom from a methylene group.

Regression Diagnostics: Identifying Influential Data and Sources of Collinearity

Abstract: 1. Introduction and Overview. 2. Detecting Influential Observations and Outliers. 3. Detecting and Assessing Collinearity. 4. Applications and Remedies. 5. Research Issues and Directions for Extensions. Bibliography. Author Index. Subject Index.

Sexually transmitted diseases treatment guidelines.

Abstract: The MMWR series of publications is published by the Office of Surveillance, Epidemiology, and Laboratory Services, Centers for Disease Control and Prevention (CDC), U.S. Department of Health and Human Services, Atlanta, GA 30333.