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Selected AbstractsCellular and molecular mechanisms in chronic obstructive pulmonary disease: an overviewCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2004A. Di Stefano Summary In the last decade, the analysis of bronchial biopsies and lung parenchyma obtained from chronic obstructive pulmonary disease (COPD) patients compared with those from smokers with normal lung function and non-smokers has provided new insights on the role of the different inflammatory and structural cells, their signalling pathways and mediators, contributing to a better knowledge of the pathogenesis of COPD. This review summarizes and discusses the lung pathology of COPD patients with emphasis on inflammatory cell phenotypes that predominate in different clinical conditions. In bronchial biopsies, a cascade of events takes place during progression from mild-to-severe disease. T lymphocytes, particularly CD8+ cells and macrophages are the prevalent inflammatory cells in the lung of healthy smokers and patients with mild COPD, while total and activated neutrophils predominate in severe COPD. The number of CD4+, CD8+ cells and macrophages expressing nuclear factor-kappa B (NF-,B), STAT-4 and IFN-, proteins as well as endothelial adhesion molecule-1 in endothelium is increased in mild/moderate disease. In contrast, activated neutrophils (MPO+ cells) and increased nitrotyrosine immunoreactivity develops in severe COPD. In bronchial biopsies obtained during COPD exacerbations, some studies have shown an increased T cell and granulocyte infiltration. Regular treatment with high doses of inhaled glucocorticoids does not significantly change the number of inflammatory cells in bronchial biopsies from patients with moderate COPD. The profile in lung parenchyma is similar to bronchial biopsies. ,Healthy' smokers and mild/moderate diseased patients show increased T lymphocyte infiltration in the peripheral airways. Pulmonary emphysema is associated with a general increase of inflammatory cells in the alveolar septa. The molecular mechanisms driving the lymphocyte and neutrophilic prevalence in mild and severe disease, respectively, needs to be extensively studied. Up-regulation of pro-inflammatory transcription factors NF-,B and STAT-4 in mild, activated epithelial and endothelial cells in the more severe disease may contribute to this differential prevalence of infiltrating cells. [source] Review of bupropion for smoking cessationDRUG AND ALCOHOL REVIEW, Issue 2 2003ROBYN RICHMOND Abstract The advent of bupropion hydrochloride sustained release (Zyban) has heralded a major change in the options available for smoking cessation pharmacotherapy. Bupropion is a selective re-uptake inhibitor of dopamine and noradrenalin which prevents or reduces cravings and other features of nicotine withdrawal. Bupropion is a useful oral and non-nicotine form of pharmacotherapy for smoking cessation. For this review a total of 221 papers were reviewed plus poster presentations. This review examines in detail original clinical trials on efficacy, categorised according to whether they were acute treatment trials in healthy smokers; studies in specific populations such as people with depression, chronic obstructive pulmonary disease (COPD) or cardiovascular disease; or relapse prevention studies. Overall, these studies in varying populations comprising over four thousand subjects, showed bupropion consistently produces a positive effect on smoking cessation outcomes. The evidence highlights the major public health role that bupropion has in smoking cessation. The methodological issues of published clinical trials reporting one year outcomes were examined in detail including: completeness of follow-up; loss to follow-up; intention to treat analysis; blindness of assessment; and validation of smoking status. The review discusses contraindications, adverse effects, dose and overdose, addictive potential, and the role of bupropion in reducing cessation-related weight gain. Bupropion combined with or compared to other pharmacotherapies (nicotine patch; nortriptyline) is considered. Impressive evidence exists for the use of bupropion in smoking cessation among difficult patients who are hard-core smokers such as those with cardiovascular disease, chronic obstructive pulmonary disease (COPD) and depression. Bupropion reduces withdrawal symptoms as well as weight gain and is effective for smoking cessation for people with and without a history of depression or alcoholism. Serious side effects of bupropion use are rare. The major safety issue with bupropion is risk of seizures (estimated at approximately 0.1%) and it should not be prescribed to patients with a current seizure disorder or any history of seizures. In clinical trials of bupropion for smoking cessation no seizures were reported. Allergic reactions occur at a rate of approximately 3% and minor adverse effects are common including dry mouth and insomnia. [source] The cost-effectiveness of antidepressants for smoking cessation in chronic obstructive pulmonary disease (COPD) patientsADDICTION, Issue 12 2009Constant P. Van Schayck ABSTRACT Objectives In healthy smokers, antidepressants can double the odds of cessation. Because of its four times lower costs and comparable efficacy in healthy smokers, nortriptyline appears to be favourable compared to bupropion. We assessed which of both drugs was most effective and cost-effective in stopping smoking after 1 year compared with placebo among smokers at risk or with existing chronic obstructive pulmonary disease (COPD). Methods A total of 255 participants, aged 30,70 years, received smoking cessation counselling and were assigned bupropion, nortriptyline or placebo randomly for 12 weeks. Prolonged abstinence from smoking was defined as a participant's report of no cigarettes from week 4 to week 52, validated by urinary cotinine. Costs were calculated using a societal perspective and uncertainty was assessed using the bootstrap method. Results The prolonged abstinence rate was 20.9% with bupropion, 20.0% with nortriptyline and 13.5% with placebo. The differences between bupropion and placebo [relative risk (RR) = 1.6; 95% confidence interval (CI) 0.8,3.0] and between nortriptyline and placebo (RR = 1.5; 95% CI 0.8,2.9) were not significant. Severity of airway obstruction did not influence abstinence significantly. Societal costs were ,1368 (2.5th,97.5th percentile 193,5260) with bupropion, ,1906 (2.5th,97.5th 120,17 761) with nortriptyline and ,1212 (2.5th,97.5th 96,6602) with placebo. Were society willing to pay more than ,2000 for a quitter, bupropion was most likely to be cost-effective. Conclusions Bupropion and nortriptyline seem to be equally effective, but bupropion appears to be more cost-effective when compared to placebo and nortriptyline. This impression holds using only health care costs. As the cost-effectiveness analyses concern some uncertainties, the results should be interpreted with care and future studies are needed to replicate the findings. [source] Epilepsy and pregnancy: effect of antiepileptic drugs and lifestyle on birthweightBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 7 2000Christian Lodberg Hvas Research Fellow Objective To investigate the impact of epilepsy and antiepileptic drugs on length of gestation and anthropometric measures of the newborn. Design Cohort study based on questionnaires mailed to all pregnant women who attended for prenatal care at our department from August 1989 to January 1997. Setting Department of Obstetrics and Gynaecology at Aarhus University Hospital, Denmark. Participants One hundred and ninety-three singleton pregnancies in women with epilepsy were compared with 24,094 singleton pregnancies in women without epilepsy. Main outcome measures Preterm delivery, small for gestational age, mean gestational age, gestational age-adjusted birthweight, head circumference, and body length. Results Children of women with epilepsy who smoked had lower gestational age and were at increased risk of preterm delivery (OR 3.4; 95% CI 1.8,6.5), compared with children born by nonepileptic women who smoked. Birthweight adjusted for gestational age was reduced by 102 g (95% CI 40,164) in women with epilepsy, and the risk of delivering a child who was small for gestational age was increased (adjusted OR 1.9, 95% CI 1.3,2.7), compared with women without epilepsy. Newborn babies of women with epilepsy treated by drugs had a reduced adjusted birthweight (208 g, 95% CI 116,300), head circumference (0.4 cm, 95% CI 0.0.0.7), and body length (0.5 cm, 95% CI 0.1,1.0), compared with the newborn infants of women without epilepsy. Conclusions Women with epilepsy who smoked were at increased risk of preterm delivery compared with healthy smokers. Children of women with drug treated epilepsy had lower birthweight, length, and head circumference than children of women without epilepsy. [source] Effects of nicotine on cytochrome P450 2A6 and 2E1 activitiesBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 2 2010Janne Hukkanen WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT , Smoking slows the metabolism of nicotine and accelerates the metabolism of chlorzoxazone. , Nicotine is a useful probe for phenotyping cytochrome P450 2A6 activity and chlorzoxazone is a frequently used probe for CYP2E1 activity. , The tobacco smoke constituents responsible for the reduced CYP2A6 and increased CYP2E1 activities are unknown. WHAT THIS PAPER ADDS , This study demonstrates that CYP2A6 and CYP2E1 activities are not affected by nicotine dosing. , High-dose nicotine treatment has a low potential of interaction with CYP2A6 and CYP2E1 substrates. , The mechanisms of tobacco smoke-elicited changes in CYP2A6 and CYP2E1 activities are yet to be determined. AIMS Smoking slows the metabolism of nicotine and accelerates the metabolism of chlorzoxazone, which are probe reactions for cytochrome P450 2A6 (CYP2A6) and CYP2E1 activities, respectively. We aimed to determine the role of nicotine in these metabolic effects of cigarette smoking. METHODS The study had a single-blind, randomized, crossover two-arm design. Twelve healthy smokers were given two transdermal patches with 42-mg nicotine a day or placebo patches, each for 10 days. The subjects abstained from smoking during the study arms. Oral chlorzoxazone was given on day 7 and deuterium-labelled nicotine-d2 and cotinine-d4 infusion on day 8. RESULTS There was no significant influence of transdermal nicotine administration on pharmacokinetic parameters of nicotine-d2 or on the formation of cotinine-d2. Nicotine decreased the volume of distribution (62.6 vs. 67.7 l, 95% confidence interval of the difference ,9.7, ,0.6, P= 0.047) of infused cotinine-d4. There were no significant differences in disposition kinetics of chlorzoxazone between the treatments. CONCLUSIONS CYP2A6 and CYP2E1 activities are not affected by nicotine. The tobacco smoke constituents responsible for the reduced CYP2A6 and increased CYP2E1 activities remain unknown. [source] MTHFR C677T polymorphism in chronic pancreatitis and pancreatic adenocarcinomaCELL BIOCHEMISTRY AND FUNCTION, Issue 6 2008Ivan Nisevic Abstract Chronic pancreatitis and pancreatic adenocarcinoma are extensively studied as common and potentially lethal disorders. However, their causes and genetic background in most cases remain unclear. The C677T polymorphism in 5,,10,-methylenetetrahydrofolate reductase (MTHFR) gene may modulate the risk of pancreatic disorders. In this study, we tested whether MTHFR C677T polymorphism is associated with chronic pancreatitis and pancreatic adenocarcinoma in the Serbian population. DNA was extracted from blood samples of 51 chronic pancreatitis patients, 21 pancreatic adenocarcinoma patients, and a control group consisting of 50 healthy smokers. The MTHFR C677T polymorphism was analyzed by polymerase chain reaction,restriction fragment length polymorphism (PCR,RFLP) technique. Although, no statistically significant differences were observed in the distribution of MTHFR genotype or allele frequencies between patients and control groups, the results showed an increased frequency of homozygotes for MTHFR C677T polymorphism in chronic pancreatitis patients (14%) and a decreased frequency in pancreatic adenocarcinoma patients (5%) in comparison to the control group (8%). We speculate that the MTHFR C677T polymorphism could act as a possible risk factor for chronic pancreatitis and a possible protective factor in pancreatic adenocarcinoma. This observation needs further investigation in prospective studies on a larger number of patients, in which the effect of other genetic and environmental factors should also be taken into consideration. Copyright © 2008 John Wiley & Sons, Ltd. [source] Cellular and molecular mechanisms in chronic obstructive pulmonary disease: an overviewCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2004A. Di Stefano Summary In the last decade, the analysis of bronchial biopsies and lung parenchyma obtained from chronic obstructive pulmonary disease (COPD) patients compared with those from smokers with normal lung function and non-smokers has provided new insights on the role of the different inflammatory and structural cells, their signalling pathways and mediators, contributing to a better knowledge of the pathogenesis of COPD. This review summarizes and discusses the lung pathology of COPD patients with emphasis on inflammatory cell phenotypes that predominate in different clinical conditions. In bronchial biopsies, a cascade of events takes place during progression from mild-to-severe disease. T lymphocytes, particularly CD8+ cells and macrophages are the prevalent inflammatory cells in the lung of healthy smokers and patients with mild COPD, while total and activated neutrophils predominate in severe COPD. The number of CD4+, CD8+ cells and macrophages expressing nuclear factor-kappa B (NF-,B), STAT-4 and IFN-, proteins as well as endothelial adhesion molecule-1 in endothelium is increased in mild/moderate disease. In contrast, activated neutrophils (MPO+ cells) and increased nitrotyrosine immunoreactivity develops in severe COPD. In bronchial biopsies obtained during COPD exacerbations, some studies have shown an increased T cell and granulocyte infiltration. Regular treatment with high doses of inhaled glucocorticoids does not significantly change the number of inflammatory cells in bronchial biopsies from patients with moderate COPD. The profile in lung parenchyma is similar to bronchial biopsies. ,Healthy' smokers and mild/moderate diseased patients show increased T lymphocyte infiltration in the peripheral airways. Pulmonary emphysema is associated with a general increase of inflammatory cells in the alveolar septa. The molecular mechanisms driving the lymphocyte and neutrophilic prevalence in mild and severe disease, respectively, needs to be extensively studied. Up-regulation of pro-inflammatory transcription factors NF-,B and STAT-4 in mild, activated epithelial and endothelial cells in the more severe disease may contribute to this differential prevalence of infiltrating cells. [source] |