The role of air nicotine in explaining racial differences in cotinine among tobacco-exposed children

OBJECTIVE: African-American children have higher rates of tobacco-associated morbidity. Few studies have objectively measured racial differences in the exposure of children to tobacco smoke. The objective of this study was to test whether African-American children have higher levels of cotinine compared to white children while accounting for ambient measures of tobacco smoke. SETTING: Community-based sample of asthmatic children (n = 220) enrolled in an environmental tobacco smoke (ETS) reduction trial. PARTICIPANTS: A biracial sample (55% African American) of children with asthma aged 5 to 12 years who were routinely exposed to ETS. MEASUREMENTS: We measured cotinine levels in serum and hair samples at baseline, 6 months, and 12 months. We measured the level of ETS exposure over a 6-month period by placing air nicotine dosimeters in the homes of the children at baseline and at 6-month study visits. RESULTS: African-American children had significantly higher levels of cotinine at all time points in the study. At the 12-month visit, African-American children had higher levels of serum cotinine (1.39 mug/dL vs 0.80 mug/dL, p = 0.001) and hair cotinine (0.28 ng/mg vs 0.08 ng/mg, p < 0.0001) when compared with white children. In a repeated-measures analysis, African-American children had significantly higher levels of serum cotinine (beta = 0.28, p = 0.04) and hair cotinine (beta = 1.40, p < 0.0001) compared with white children. Air nicotine levels and housing volume were independently associated with higher levels of cotinine. CONCLUSIONS: Among children with asthma, African-American children have higher levels of serum and hair cotinine compared with white children.     

Intragastric nicotine protects against 40% ethanol-induced gastric mucosal injury despite pretreatment with propranolol orN-ethylmaleimide in rats

We tested the hypotheses that the protective effect of intragastric nicotine against ethanol-induced gastric mucosal injury is dependent on propranolol- orN-ethylmaleimide-sensitive mechanisms. Propranolol was administered in doses (2 and 20 mg/kg) that provided dose-related blockade of -adrenoceptors (significant decreases in heart rate).N-Ethylmaleimide was administered in doses that previously had been shown to increase gastric vascular permeability (10 mg/kg) or inhibit gastric mucosal sulfhydryl compounds (50 mg/kg). At 0.5 hr after these or control subcutaneous pretreatments, the rats received intragastric nicotine (4 mg/kg) or vehicle. One hour later 40% ethanol was given intragastrically. The gastric corpus mucosal lesions were recorded by polaroid photographs after another hour, and their areas measured unbiasedly by computerized image analysis. The results showed thatN-ethylmaleimide, but not propranolol, aggravated ethanol-induced gastric mucosal injury. The protective effect of intragastric nicotine was not modified by either pretreatment. We conclude that the mechanism mediating intragastric nicotine protection against 40% ethanol-induced gastric mucosal injury is independent of propranolol- orN-ethylmaleimide-sensitive mechanisms.Supported by Veterans Administration Medical Research Funds, and in part by research grants (0162-01, 02 and 0291-01) from the Smokeless Tobacco Research Council, Inc., and by funds (1RT 80) provided by the Cigarette and Tobacco Surtax Fund of the State of California through the Tobacco-Related Disease Research Program of the University of California to FWL. Dr. Endoh is a recipient of the University of California Tobacco-Related Disease Research Program Research Fellowship Award (FT 37).     

Comparative dynamics of four smoking withdrawal symptom scales

Aims To examine the association of person‐specific trajectories of withdrawal symptoms of urge‐to‐smoke, negative affect, physical symptoms and hunger during the first 7 days after smoking cessation with abstinence at end of treatment (EOT) and at 6 months. Design Hierarchical linear modeling (HLM) was used to model person‐specific trajectory parameters (level, slope, curvature and volatility) for withdrawal symptoms. Setting University‐based smoking cessation trials. Participants Treatment‐seeking smokers in clinical trials of transdermal nicotine versus nicotine spray (n = 514) and bupropion versus placebo (n = 421). Measurements Self‐reported withdrawal symptoms for 7 days after the planned quit date, and 7‐day point prevalence and continuous abstinence at EOT and 6 months. Findings In regressions that included trajectory parameters for one group of withdrawal symptoms, both urge‐to‐smoke and negative affect were predictive of abstinence while physical symptoms and hunger were generally not predictive. In stepwise regressions that included the complete set of trajectory parameters across withdrawal symptoms (for urge‐to‐smoke, negative affect, physical symptoms and hunger), with a single exception only the trajectory parameters for urge‐to‐smoke were predictive. Area under the receiver operator characteristic curve was 0.594 for covariates alone, and 0.670 for covariates plus urge‐to‐smoke trajectory parameters. Conclusions Among a number of different withdrawal symptoms (urge‐to‐smoke, negative affect, physical symptoms and hunger) urge‐to‐smoke trajectory parameters (level, slope and volatility) over the first 7 days of smoking cessation show the strongest prediction of both short‐ and long‐term relapse. Other withdrawal symptoms increase the predictive ability by negligible amounts.     

DSM criteria for tobacco use disorder and tobacco withdrawal: a critique and proposed revisions for DSM-5

Aims This paper aims to identify appropriate criteria for tobacco dependence assessment, evaluate relevant research and suggest revisions that may be incorporated into DSM‐5. Methods Desirable conceptual and psychometric features of tobacco dependence assessments were identified, including the types of outcomes against which such assessment should be validated. DSM‐IV criteria were matched against these criteria and compared with other dependence measures. Results DSM‐IV criteria were found to be ambiguous, little used in tobacco research, and have relatively low predictive validity. Other dependence measures were found to have greater validity in the prediction of important dependence features such as relapse likelihood. Strength of urges to smoke on typical smoking days and during abstinence, markers of nicotine intake or frequency of smoking and latency to smoke soon after waking were found to be useful dependence measures. Conclusion The use and utility of DSM‐5 will be enhanced by eliminating most DSM‐IV criteria and adding new ones based on smoking pattern, smoking heaviness, and the severity of craving during periods of smoking and withdrawal.     

尼古丁和美卡拉明对牙周致病微生物的影响

目的 探讨尼古丁和美卡拉明对主要牙周致病微生物生长及生物膜形成的影响.方法 采用二倍稀释法,研究尼古丁对牙龈卟啉单胞菌和伴放线放线杆菌的最低抑菌浓度(MIC)和最低杀菌浓度(MBC).通过酶标仪测定吸光度值,研究在1/16 MIC、1/8 MIC、1/4 MIC、1/2 MIC、MIC等不同浓度的尼古丁对这2种细菌生物膜形成的影响.结果 尼古丁对2种细菌的菌悬液的MIC均为8 mg·mL-1,MBC为16 mg·mL-1.尼古丁浓度逐渐增加时,生物膜吸光度值逐渐增大;继续增加浓度,吸光度值减小;在8 mg.mL-1时,吸光度值减小到最低值,最低生物膜抑制浓度为8 mg.mL-1.添加尼古丁受体拮抗剂美卡拉明组较对照组吸光度值高.结论 小剂量的尼古丁能增加牙龈卟啉单胞菌和伴放线放线杆菌的生物膜形成,浓度继续增加则抑制生物膜形成,加入美卡拉明后降低尼古丁浓度,更能明显观察到尼古丁对两种细菌生物膜的促进作用.     

Short-term Changes in Self-rating Depression Scale Scores after Smoking Cessation in Neurotic Patients

Objective The psychological status is a key factor in smoking continuance. However, details on short-term changes in mild depressive states after smoking cessation (SC) are still unknown. The purpose of the present study was to investigate these short-term changes. Methods A total of 989 patients who visited our SC Clinic were assessed using the Zung Self-Rating-Depression-Scale (SDS), an official instrument to measure depressive tendencies. The participants were classified into normal and neurotic groups based on their SDS scores during their initial visit; they were assessed again 2, 4, 8, and 12 weeks thereafter. Results The majority of patients in the neurotic group were women. These patients were also younger, with a higher nicotine dependence, and presented with a lower successful SC rate than the patients in the normal group. A decrease in SDS scores after starting the SC treatment was observed only in the neurotic group, especially during the first two weeks. In patients who continued to smoke, no improvement in depressive tendencies was noted in this period. Conclusion Depressive tendencies of patients with neurosis improve in the initial stages of the SC treatment (i.e., within two weeks after starting the treatment). This finding fills the mentioned knowledge gap regarding the effects of SC on mild depressive states in the short term.