Many flavor ingredients are often used in potentially reduced-risk tobacco products (such as e-vapor products). Although most are "generally recognized as safe (GRAS)" when used in food, there is limited information available on their long-term health effects when delivered by inhalation. While obtaining route-of-exposure-specific toxicological data on flavor ingredients is critical to product evaluation, the large number of individual flavor ingredients available and their potential combinations render classical toxicological assessment approaches impractical, as they may require years of preclinical investigations and thousands of laboratory animals.
View Article and Find Full Text PDFPhysiologically based pharmacokinetic (PBPK) modeling can be a useful tool for characterizing nicotine pharmacokinetics (PK) from use of tobacco products. We expand a previously published PBPK model to simulate a nicotine PK profile, following single or multiple use of various tobacco products [cigarettes, smokeless tobacco, and electronic nicotine delivery systems, or a nicotine inhaler (NICOTROL)] The uptake route in the model was designed to allow for three uptake compartments: buccal cavity (BC), upper respiratory tract (URT) (conducting and transitional airways) and lower respiratory tract (alveolar region). Within each region, the model includes product-specific descriptions of the flux of nicotine into plasma, as well as the flux of nicotine from the BC and URT to the gastrointestinal tract.
View Article and Find Full Text PDFE-cigarettes have become the most commonly used tobacco products among youth in the United States (US) recently. It is not clear whether there is a causal relationship between e-cigarette use and the onset of cigarette smoking. The "common liability" theory postulates that the association between e-cigarette use and cigarette smoking can be attributed to a common risk construct of using tobacco products.
View Article and Find Full Text PDFBackground: Population models have been developed to evaluate the impact of new tobacco products on the overall population. Reliable input parameters such as longitudinal tobacco use transitions are needed to quantify the net population health impact including the number of premature deaths prevented, additional life years, and changes in cigarette smoking prevalence.
Methods: This secondary analysis assessed transition patterns from PATH wave 1 (2013-14) to wave 2 (2014-15) among adult exclusive cigarette smokers, exclusive e-cigarette users, and dual users.
Introduction: Few clinical studies involving cigarettes have provided a comprehensive picture of smoke exposure, test article characterization, and insights into sensory properties combined. The purpose of these pilot studies was to determine whether cigarettes with different levels of nicotine but similar tar levels would affect sensory experience or smoking behavior so as to significantly alter levels of selected biomarkers of exposure (BOE).
Methods: In 2 confined, double-blind studies, 120 adult smokers switched from Marlboro Gold cigarettes at baseline to either 1 of 2 lower nicotine cigarettes or 1 of 2 higher nicotine cigarettes and then to the other cigarette after 5 days.
Introduction: The nicotine bolus theory states that the dependence-producing potential of cigarettes relates to a rapid increase in nicotine at brain receptor sites. It has been suggested that ammonia, a compound typically found in tobacco products, further increases the amount of nicotine absorbed and its absorption rate. The aim of this study was to determine whether different ammonia yields in cigarettes affected the rate or amount of nicotine absorption from the lungs to arterial circulation.
View Article and Find Full Text PDFIntroduction: We developed an automated sampling system to allow multiple, discrete blood samples from a human participant to be collected rapidly and immediately following cigarette smoke exposure. We reported the details of the sampling system along with the results of a pilot study for evaluation of the system.
Methods: Components of the system include silastic tubing, solenoid pinch valves, a peristaltic pump, and a fraction collector.
The authors studied the etiology, outcome and risk factors of 339 cases of infective endocarditis (IE) in Slovakia over the last 10 years. Aortic valve was infected in 59.9%, mitral in 38.
View Article and Find Full Text PDFThis study prospectively investigated all 157 cases of Acinetobacter baumannii bacteremia occurring in major university hospitals or tertiary care institutions in Slovakia during 1999 in order to determine the antimicrobial susceptibility, risk factors and outcome. Resistance to meropenem was 7.4, gentamicin 35.
View Article and Find Full Text PDFAmphotericin B (AmB) resistance in Candida spp. is very rare. Three cases of fungemia, due to amphotericin B-resistant Candida spp.
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