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Explaining Test Results to Parents
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Electronic cigarettes and nicotine dependence: evolving products, evolving problems
Electronic cigarettes (ECIGs) use an electric heater to aerosolize a liquid that usually contains propylene glycol, vegetable glycerin, flavorants, and the dependence-producing drug nicotine. ECIG-induced nicotine dependence has become an important concern, as some ECIGs deliver very little nicotine while some may exceed the nicotine delivery profile of a tobacco cigarette. This variability is relevant to tobacco cigarette smokers who try to switch to ECIGs. Products with very low nicotine delivery may not substitute for tobacco cigarettes, so that ECIG use is accompanied by little reduced risk of cigarette-caused disease. Products with very high nicotine delivery may make quitting ECIGs particularly difficult should users decide to try. For non-smokers, the wide variability of ECIGs on the market is especially troublesome: low nicotine products may lead them to initiate nicotine self-administration and progress to higher dosing ECIGs or other products, and those that deliver more nicotine may produce nicotine dependence where it was not otherwise present. External regulatory action, guided by strong science, may be required to ensure that population-level nicotine dependence does not rise
Electronic cigarettes and nicotine dependence: evolving products, evolving problems
Electronic cigarettes (ECIGs) use an electric heater to aerosolize a liquid that usually contains propylene glycol, vegetable glycerin, flavorants, and the dependence-producing drug nicotine. ECIG-induced nicotine dependence has become an important concern, as some ECIGs deliver very little nicotine while some may exceed the nicotine delivery profile of a tobacco cigarette. This variability is relevant to tobacco cigarette smokers who try to switch to ECIGs. Products with very low nicotine delivery may not substitute for tobacco cigarettes, so that ECIG use is accompanied by little reduced risk of cigarette-caused disease. Products with very high nicotine delivery may make quitting ECIGs particularly difficult should users decide to try. For non-smokers, the wide variability of ECIGs on the market is especially troublesome: low nicotine products may lead them to initiate nicotine self-administration and progress to higher dosing ECIGs or other products, and those that deliver more nicotine may produce nicotine dependence where it was not otherwise present. External regulatory action, guided by strong science, may be required to ensure that population-level nicotine dependence does not rise
Waterpipes and Electronic Cigarettes: Increasing Prevalence and Expanding Science
The prevalence of noncigarette tobacco product use is on the rise across the globe, especially for waterpipes (also known as hookah, narghile, and shisha) and electronic cigarettes (e-cigarettes). The scientific literature reveals that waterpipe tobacco smoking is associated with exposure to a variety of toxicants that can cause short- and long-term adverse health events. In contrast, there is far less evidence of health harms related to e-cigarette use, although the variety of products in this category makes it difficult to generalize. We searched the PubMed database for all publications on waterpipes and e-cigarettes from January 2000 to March 2014. The number of publications on waterpipes rose in a slow, linear pattern during this time, while the number of publications on e-cigarettes showed exponential growth. The different trends suggest there may be more interest in studying a novel nicotine product (the e-cigarette) over a traditional tobacco product (the waterpipe). We posit that, although the specific research needs for these products are different, public health would be served best by a more equitable research approach. Scientists should continue to devote attention to understanding the unknown long-term health effects of e-cigarettes and their potential to serve as harm reduction or smoking cessation tools while simultaneously investigating how to reduce waterpipe smoking given that it exposes users to toxicants known to cause harm to health. Recent regulatory action in the United States, which proposes to include waterpipes and e-cigarettes under some of the same regulations as tobacco cigarettes, makes such research particularly timely
Estimating the beginning of the waterpipe epidemic in Syria
BACKGROUND: Waterpipe smoking is becoming a global public health problem, especially in the Eastern Mediterranean region (EMR). METHODS: We try in this study, which is a cross sectional survey among a representative sample of waterpipe smokers in cafes/restaurants in Aleppo-Syria, to assess the time period for the beginning of this new smoking hype. We recruited 268 waterpipe smokers (161 men, 107 women; mean age ± standard deviation (SD) 30.1 ± 10.2, response rate 95.3%). Participants were divided into 4 birth cohorts (≤ 1960, 1961–1970, 1971–1980, >1980) and year of initiation of waterpipe smoking and daily cigarette smoking were plotted according to these birth cohorts. RESULTS: Data indicate that unlike initiation of cigarette smoking, which shows a clear age-related pattern, the nineties was the starting point for most of waterpipe smoking implicating this time period for the beginning of the waterpipe epidemic in Syria. CONCLUSION: The introduction of new flavored and aromatic waterpipe tobacco (Maassel), and the proliferation of satellite and electronic media during the nineties may have helped spread the new hype all over the Arab World
Triangulating Abuse Liability Assessment for Flavoured Cigar Products Using Physiological, Behavioural Economic and Subjective Assessments: A Within-subjects Clinical Laboratory Protocol
Introduction In the USA, Food and Drug Administration regulations prohibit the sale of flavoured cigarettes, with menthol being the exception. However, the manufacture, advertisement and sale of flavoured cigar products are permitted. Such flavourings influence positive perceptions of tobacco products and are linked to increased use. Flavourings may mask the taste of tobacco and enhance smoke inhalation, influencing toxicant exposure and abuse liability among novice tobacco users. Using clinical laboratory methods, this study investigates how flavour availability affects measures of abuse liability in young adult cigarette smokers. The specific aims are to evaluate the effect of cigar flavours on nicotine exposure, and behavioural and subjective measures of abuse liability.
Methods and analyses Participants (projected n=25) are healthy smokers of five or more cigarettes per day over the past 3 months, 18–25 years old, naive to cigar use (lifetime use of 50 or fewer cigar products and no more than 10 cigars smoked in the past 30 days) and without a desire to quit cigarette smoking in the next 30 days. Participants complete five laboratory sessions in a Latin square design with either their own brand cigarette or a session-specific Black & Mild cigar differing in flavour (apple, cream, original and wine). Participants are single-blinded to cigar flavours. Each session consists of two 10-puff smoking bouts (30 s interpuff interval) separated by 1 hour. Primary outcomes include saliva nicotine concentration, behavioural economic task performance and response to various questionnaire items assessing subjective effects predictive of abuse liability. Differences in outcomes across own brand cigarette and flavoured cigar conditions will be tested using linear mixed models
Genetic Risks to Nicotine Dependence Predict Negative Mood and Affect in Current Non-Smokers
Nicotine is the psychoactive agent involved in nicotine dependence. However, nicotine as a drug and its effects on human psychology are largely under-investigated in genetic studies. In this study, we recruited 208 current non-smokers to evaluate the effect of nicotine and its relationship to genetic risks to nicotine dependence. Exploratory and confirmatory factor analyses, as well as measurement invariance testing, were conducted to evaluate the latent factor structures of the POMS, PANAS and DEN questionnaires across 3 nicotine doses. Structural models were used to examine the effects of nicotine and their relationship to genetic risks of nicotine dependence. We found that nicotine administration led to the change of both measurement construct and factor means, indicating the causal effect of nicotine on the psychological responses. The genotypes of rs588765 predicted the scores of the DEN Confused and Dizzy factors (p = 0.0003 and 0.001 respectively) and rs16969968 and rs588765 were associated with the PANAS Nervous factor (p = 0.006 and 0.007 respectively). Our study suggested that genetic risk of nicotine dependence is associated with acute psychological responses. The integration of psychometric analyses and dose effects could be a powerful approach for genetic study of nicotine dependence
Genetic Risks to Nicotine Dependence Predict Negative Mood and Affect in Current Non-Smokers
Nicotine is the psychoactive agent involved in nicotine dependence. However, nicotine as a drug and its effects on human psychology are largely under-investigated in genetic studies. In this study, we recruited 208 current non-smokers to evaluate the effect of nicotine and its relationship to genetic risks to nicotine dependence. Exploratory and confirmatory factor analyses, as well as measurement invariance testing, were conducted to evaluate the latent factor structures of the POMS, PANAS and DEN questionnaires across 3 nicotine doses. Structural models were used to examine the effects of nicotine and their relationship to genetic risks of nicotine dependence. We found that nicotine administration led to the change of both measurement construct and factor means, indicating the causal effect of nicotine on the psychological responses. The genotypes of rs588765 predicted the scores of the DEN Confused and Dizzy factors (p = 0.0003 and 0.001 respectively) and rs16969968 and rs588765 were associated with the PANAS Nervous factor (p = 0.006 and 0.007 respectively). Our study suggested that genetic risk of nicotine dependence is associated with acute psychological responses. The integration of psychometric analyses and dose effects could be a powerful approach for genetic study of nicotine dependence
Srs2 mediates PCNA-SUMO-dependent inhibition of DNA repair synthesis
Completion of DNA replication needs to be ensured even when challenged with fork progression problems or DNA damage. PCNA and its modifications constitute a molecular switch to control distinct repair pathways. In yeast, SUMOylated PCNA (S-PCNA) recruits Srs2 to sites of replication where Srs2 can disrupt Rad51 filaments and prevent homologous recombination (HR). We report here an unexpected additional mechanism by which S-PCNA and Srs2 block the synthesis-dependent extension of a recombination intermediate, thus limiting its potentially hazardous resolution in association with a cross-over. This new Srs2 activity requires the SUMO interaction motif at its C-terminus, but neither its translocase activity nor its interaction with Rad51. Srs2 binding to S-PCNA dissociates Polδ and Polη from the repair synthesis machinery, thus revealing a novel regulatory mechanism controlling spontaneous genome rearrangements. Our results suggest that cycling cells use the Siz1-dependent SUMOylation of PCNA to limit the extension of repair synthesis during template switch or HR and attenuate reciprocal DNA strand exchanges to maintain genome stability. © 2013 European Molecular Biology Organization
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