The design of a new cigarette that heats rather than burns tobacco calls for modifications to the Federal Trade Commission (FTC) method for analytical smoking. These changes include eliminating sample conditioning at 75 degrees F and 60% RH, exercising greater care in lighting cigarettes, and smoking cigarettes to self-extinguishment rather than to a predetermined butt length as a measure of complete consumption. By several gross analytical measures, smoke condensate from the new cigarette differs substantially from that of tobacco-burning cigarettes. This is inferred from the lack of coloration of smoke condensate collected on Cambridge filters. Elemental analysis demonstrates reduced carbon and nitrogen content concurrent with increased hydrogen. Thermogravimetric analysis shows almost quantitative weight loss at Tmax = 220 degrees C. Ultraviolet (UV) spectrophotometric analysis shows greatly reduced levels of tobacco-derived smoke components and qualitative differences in chemical entities being measured. By design, the heat required for smoke formation is supplied by a carbon heat source embedded in the cigarette tip. Tobacco contained in the cigarette is not burned and is exposed to temperature less than 300 degrees C. Thus, it is apparent (1) that smoke from the new cigarette contains little or no "tar" as tar is classically defined, and (2) that the FTC method even as modified to account for cigarette design differences is appropriate only for determination of nicotine and carbon monoxide yielded from this cigarette.
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Int J Drug Policy
January 2025
Division of Hepatology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Main Road, Observatory, Cape Town, South Africa. Electronic address:
Background: Hepatitis B virus (HBV) and hepatitis C virus (HCV) are estimated to be of the most prevalent infectious diseases in correctional settings worldwide. However, viral hepatitis services have not been routinely integrated into South African correctional facilities. We aimed to assess prevalence of HBV infection and HCV infection among people accessing HIV services and assess the feasibility of viral hepatitis service integration in a South African correctional centre.
View Article and Find Full Text PDFClin Microbiol Infect
January 2025
Infectious Disease Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK. Electronic address:
Background: The World Health Organization (WHO) recommends antiretroviral therapy (ART) containing two nucleoside reverse transcriptase inhibitors (NRTIs) as backbone. WHO recommends tenofovir disoproxil fumarate combined with lamivudine or emtricitabine as first line in pregnancy, and zidovudine, abacavir or tenofovir alafenamide, combined with lamivudine or emtricitabine, as alternatives.
Objectives: Evaluate risk of adverse perinatal outcomes in pregnant women living with HIV (WLHIV) receiving different NRTIs.
Clin Trials
December 2024
Medical Research Council Clinical Trials Unit, University College London, London, UK.
Background: There is increasing recognition that the interpretation of active-controlled HIV prevention trials should consider the counterfactual placebo HIV incidence rate, that is, the rate that would have been observed if the trial had included a placebo control arm. The PrEPVacc HIV vaccine and pre-exposure prophylaxis trial (NCT04066881) incorporated a pre-trial registration cohort partly for this purpose. In this article, we describe our attempts to model the counterfactual placebo HIV incidence rate from the registration cohort.
View Article and Find Full Text PDFLancet HIV
January 2025
Fundación IDEAA, Buenos Aires, Argentina.
Background: Dolutegravir plus lamivudine has emerged as a preferred treatment for HIV; however, initiating this regimen without baseline resistance testing raises concerns about the potential presence of pretreatment lamivudine resistance. We aimed to evaluate the efficacy of dolutegravir plus lamivudine in the absence of information on baseline resistance testing in treatment-naive people with HIV.
Methods: We did an open-label, non-inferiority, single-centre, phase 4, randomised controlled study (D2ARLING), designed to assess the efficacy and safety of dolutegravir plus lamivudine in treatment-naive people with HIV with no available baseline resistance testing.
Eur J Epidemiol
January 2025
Gerontology Research Center (GEREC), Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.
Objectives: The association between leisure-time physical activity (LTPA) and a lower risk of mortality is susceptible to bias from multiple sources. We investigated the potential of biological ageing to mediate the association between long-term LTPA and mortality and whether the methods used to account for reverse causality affect the interpretation of this association.
Methods: Study participants were twins from the older Finnish Twin Cohort (n = 22,750; 18-50 years at baseline).
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