104 resultados para Cigarette Smoke

em Deakin Research Online - Australia


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Endothelial dysfunction is a hallmark of cardiovascular disease, and the l-arginine:NO pathway plays a critical role in determining endothelial function. Recent studies suggest that smoking, a well-recognized risk factor for vascular disease, may interfere with l-arginine and NO metabolism; however, this remains poorly characterized. Accordingly, we performed a series of complementary in vivo and in vitro studies to elucidate the mechanism by which cigarette smoke adversely affects endothelial function. In current smokers, plasma levels of asymmetrical dimethyl-arginine (ADMA) were 80% higher (P=0.01) than nonsmokers, whereas citrulline (17%; P<0.05) and N-hydroxy-l-arginine (34%; P<0.05) were significantly lower. Exposure to 10% cigarette smoke extract (CSE) significantly affected endothelial arginine metabolism with reductions in the intracellular content of citrulline (81%), N-hydroxy-l-arginine (57%), and arginine (23%), while increasing ADMA (129%). CSE significantly inhibited (38%) arginine uptake in conjunction with a 34% reduction in expression of the arginine transporter, CAT1. In conjunction with these studies, CSE significantly reduced the activity of eNOS and NO production by endothelial cells, while stimulating the production of reactive oxygen species. In conclusion, cigarette smoke adversely affects the endothelial l-arginine NO synthase pathway, resulting in reducing NO production and elevated oxidative stress. In conjunction, exposure to cigarette smoke increases ADMA concentration, the latter being a risk factor for cardiovascular disease.

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Defective efferocytosis may perpetuate inflammation in smokers with or without chronic obstructive pulmonary disease (COPD). Macrophages may phenotypically polarize to classically activated M1 (proinflammatory; regulation of antigen presentation) or alternatively activated M2 (poor antigen presentation; improved efferocytosis) markers. In bronchoalveolar lavage (BAL)–derived macrophages from control subjects and smoker/ex-smoker COPD subjects, we investigated M1 markers (antigen-presenting major histocompatibility complex [MHC] Classes I and II), complement receptors (CRs), the high-affinity Fc receptor involved with immunoglobulin binding for phagocytosis (Fc-gamma receptor, FcγR1), M2 markers (dendritic cell–specific intercellular adhesion molecule-grabbing nonintegrin [DC-SIGN] and arginase), and macrophage function (efferocytosis and proinflammatory cytokine production in response to LPS). The availability of glutathione (GSH) in BAL was assessed, because GSH is essential for both M1 function and efferocytosis. We used a murine model to investigate macrophage phenotype/function further in response to cigarette smoke. In lung tissue (disaggregated) and BAL, we investigated CRs, the available GSH, arginase, and efferocytosis. We further investigated the therapeutic effects of an oral administration of a GSH precursor, cysteine l-2-oxothiazolidine-4-carboxylic acid (procysteine). Significantly decreased efferocytosis, available GSH, and M1 antigen–presenting molecules were evident in both COPD groups, with increased DC-SIGN and production of proinflammatory cytokines. Increased CR-3 was evident in the current-smoker COPD group. In smoke-exposed mice, we found decreased efferocytosis (BAL and tissue) and available GSH, and increased arginase, CR-3, and CR-4. Treatment with procysteine significantly increased GSH, efferocytosis (BAL: control group, 26.2%; smoke-exposed group, 17.66%; procysteine + smoke-exposed group, 27.8%; tissue: control group, 35.9%; smoke-exposed group, 21.6%; procysteine + smoke-exposed group, 34.5%), and decreased CR-4 in lung tissue. Macrophages in COPD are of a mixed phenotype and function. The increased efferocytosis and availability of GSH in response to procysteine indicates that this treatment may be useful as adjunct therapy for improving macrophage function in COPD and in susceptible smokers.

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Background: Exposure to other people’s cigarette smoke (environmental tobacco smoke, or ETS) is an important child health issue.
Objectives: To determine the effectiveness of interventions aiming to reduce exposure of children to ETS.
Search strategy: The Tobacco Addiction Group register of studies was searched.MEDLINE, EMBASE and four other health and psychology databases were searched electronically, bibliographies of retrieved primary studies were checked and specialists in the area consulted.
Selection criteria:
Controlled trials with or without random allocation were included in this review if they addressed participants (parents and other family members, child care workers and teachers) involved with the care and education of infants and young children (aged 0-12 years). All mechanisms for reduction of children’s environmental tobacco smoke exposure, and smoking prevention, cessation, and control programmes targeting these participants are included. These include smoke free policies and legislation, health promotion, social behavioural therapies, technology, education and clinical interventions.
Data collection and analysis: Two reviewers independently assessed studies and extracted data. Due to heterogeneity of methodologies and outcomes, no summary measures were possible and results were synthesised using narrative summaries.
Main results:
Nineteen studies met the inclusion criteria, one of which was subsequently excluded. Three interventions were targeted at populations or community settings, seven studies were conducted in the well child health care setting and eight in the ill child health care setting. Twelve of these studies are from North America. In 12 of the 18 studies there was reduction of ETS exposure for children in both intervention and comparison groups. In only four of the 18 studies was there a statistically significant intervention effect. Three of these successful studies employed intensive counselling interventions targeted to smoking parents. There is little difference between the well infant, child respiratory illness and other child illness settings as contexts for parental smoking cessation interventions. The fourth successful intervention was in the school setting targeting the ETS exposure of children from smoking fathers.
Authors’ conclusions: Brief counselling interventions, successful in the adult health setting when coming from physicians, cannot be extrapolated to adults in the setting of child health. There is limited support for more intensive counselling interventions. There is no clear evidence for differences between the respiratory, non-respiratory ill child, well child and peripartum settings as contexts for reduction of children’s ETS exposure.

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Multiple studies have demonstrated an association between cigarette smoking and increased anxiety symptoms or disorders, with early life exposures potentially predisposing to enhanced anxiety responses in later life. Explanatory models support a potential role for neurotransmitter systems, inflammation, oxidative and nitrosative stress, mitochondrial dysfunction, neurotrophins and neurogenesis, and epigenetic effects, in anxiety pathogenesis. All of these pathways are affected by exposure to cigarette smoke components, including nicotine and free radicals. This review critically examines and summarizes the literature exploring the role of these systems in increased anxiety and how exposure to cigarette smoke may contribute to this pathology at a biological level. Further, this review explores the effects of cigarette smoke on normal neurodevelopment and anxiety control, suggesting how exposure in early life (prenatal, infancy, and adolescence) may predispose to higher anxiety in later life. A large heterogenous literature was reviewed that detailed the association between cigarette smoking and anxiety symptoms and disorders with structural brain changes, inflammation, and cell-mediated immune markers, markers of oxidative and nitrosative stress, mitochondrial function, neurotransmitter systems, neurotrophins and neurogenesis. Some preliminary data were found for potential epigenetic effects. The literature provides some support for a potential interaction between cigarette smoking, anxiety symptoms and disorders, and the above pathways; however, limitations exist particularly in delineating causative effects. The literature also provides insight into potential effects of cigarette smoke, in particular nicotine, on neurodevelopment. The potential treatment implications of these findings are discussed in regards to future therapeutic targets for anxiety. The aforementioned pathways may help mediate increased anxiety seen in people who smoke. Further research into the specific actions of nicotine and other cigarette components on these pathways, and how these pathways interact, may provide insights that lead to new treatment for anxiety and a greater understanding of anxiety pathogenesis.

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 This research project demonstrated that exposure to cigarette smoke in adolescence, childhood and in utero is prospectively associated with increased levels of anxiety later in life. The results suggest smoking is a plausible risk factor for developing higher levels of anxiety, informing multiple areas for future research into anxiety pathogenesis.

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BackgroundChildren's exposure to other people's cigarette smoke (environmental tobacco smoke, or ETS) is associated with a range of adverse health outcomes for children. Parental smoking is a common source of children's exposure to ETS. Older children are also at risk of exposure to ETS in child care or educational settings. Preventing exposure to cigarette smoke in infancy and childhood has significant potential to improve children's health worldwide.ObjectivesTo determine the effectiveness of interventions aiming to reduce exposure of children to ETS.Search methodsWe searched the Cochrane Tobacco Addiction Group Specialized Register and conducted additional searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, EMBASE, CINAHL, ERIC, and The Social Science Citation Index & Science Citation Index (Web of Knowledge). Date of the most recent search: September 2013.Selection criteriaControlled trials with or without random allocation. Interventions must have addressed participants (parents and other family members, child care workers and teachers) involved with the care and education of infants and young children (aged 0 to 12 years). All mechanisms for reduction of children's ETS exposure, and smoking prevention, cessation, and control programmes were included. These include health promotion, social-behavioural therapies, technology, education, and clinical interventions.Data collection and analysisTwo authors independently assessed studies and extracted data. Due to heterogeneity of methodologies and outcome measures, no summary measures were possible and results were synthesised narratively.Main resultsFifty-seven studies met the inclusion criteria. Seven studies were judged to be at low risk of bias, 27 studies were judged to have unclear overall risk of bias and 23 studies were judged to have high risk of bias. Seven interventions were targeted at populations or community settings, 23 studies were conducted in the 'well child' healthcare setting and 24 in the 'ill child' healthcare setting. Two further studies conducted in paediatric clinics did not make clear whether the visits were to well or ill children, and another included both well and ill child visits. Thirty-six studies were from North America, 14 were in other high income countries and seven studies were from low- or middle-income countries. In only 14 of the 57 studies was there a statistically significant intervention effect for child ETS exposure reduction. Of these 14 studies, six used objective measures of children's ETS exposure. Eight of the studies had a high risk of bias, four had unclear risk of bias and two had a low risk of bias. The studies showing a significant effect used a range of interventions: seven used intensive counselling or motivational interviewing; a further study used telephone counselling; one used a school-based strategy; one used picture books; two used educational home visits; one used brief intervention and one study did not describe the intervention. Of the 42 studies that did not show a significant reduction in child ETS exposure, 14 used more intensive counselling or motivational interviewing, nine used brief advice or counselling, six used feedback of a biological measure of children's ETS exposure, one used feedback of maternal cotinine, two used telephone smoking cessation advice or support, eight used educational home visits, one used group sessions, one used an information kit and letter, one used a booklet and no smoking sign, and one used a school-based policy and health promotion. In 32 of the 57 studies, there was reduction of ETS exposure for children in the study irrespective of assignment to intervention and comparison groups. One study did not aim to reduce children's tobacco smoke exposure, but rather aimed to reduce symptoms of asthma, and found a significant reduction in symptoms in the group exposed to motivational interviewing. We found little evidence of difference in effectiveness of interventions between the well infant, child respiratory illness, and other child illness settings as contexts for parental smoking cessation interventions.Authors' conclusionsWhile brief counselling interventions have been identified as successful for adults when delivered by physicians, this cannot be extrapolated to adults as parents in child health settings. Although several interventions, including parental education and counselling programmes, have been used to try to reduce children's tobacco smoke exposure, their effectiveness has not been clearly demonstrated. The review was unable to determine if any one intervention reduced parental smoking and child exposure more effectively than others, although seven studies were identified that reported motivational interviewing or intensive counselling provided in clinical settings was effective.

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In the films of Wong Kar-wai one finds a double or parallel sensing of the sublime. Numerous characters are seen to experience perceptual moments of unbounded terror, where they are faced with the weight, enormity or formlessness of objects, things, and natural phenomena that they cannot initially or fully comprehend. These ‘textual’ sublime moments are simultaneously rendered receptively, experientially sublime through the way Wong Kar-wai conjures up a series of refracted, defamiliarised images of heightened intensity, such as bejeweled juke boxes, incandescent lampshades, thick waterfalls, and wispy cigarette smoke rising. Such awesome images are of artifice and nature, conjoined, blurred, or delineated, so that the sublime moment is of the postmodern moment, irrational and irregular, and ‘monstrous’ because of it. In the films of Wong Kar-wai, character and viewer become aligned in a process of identification in which each recognizes their mortality, and inadequacy, in the face of such dazzling, incomprehensible moments that trace across the retina of the eye. The pleasure and the pain of this is something that I will explore in this paper, using such sublime films as Fallen Angels, Chungking Express, Happy Together, In the Mood for Love, 2046, and Blueberry Nights, to illustrate my arguments.

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Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease; it is a leading cause of death and existing treatments have no proven disease-modifying effect. The mechanisms underlying this resistance are largely unknown, but suggest the presence of some self-maintaining pathogenic process, possibly initiated by cigarette smoking, that prevents the normal resolution of inflammation. We have previously reported increased production of proinflammatory cytokines and granzyme b by CD8+ T cells in COPD; costimulatory receptor/ligand interactions required include CD80:86/CD28, B7-1/CTLA4, 4-1BB/1BBL and OX40/OX40L. We hypothesized that a dysregulated expression/function of these molecules may play a role in inflammatory/autoimmune components of COPD. We analysed T cell co-stimulatory molecules in blood from 34 controls, 15 smokers and 48 COPD subjects. We assessed the potential functional relevance of CD8/CD28null cells in COPD by measuring their production of proinflammatory cytokines, co-stimulatory molecules, granzyme and perforin. A smoke-exposed murine model was applied to investigate the relative expression of CD8/CD28null T cells in blood, lung tissue and airway. CD8/CD28null cells were increased in both current- and ex-smoker COPD groups; these cells expressed significantly more interferon (IFN)-γ, OX40, 4-1BB, CTLA4, granzyme and perforin when stimulated than CD8/CD28+ T cells. There were no changes in CD4/CD28null T cells. In mice exposed to cigarette smoke for 12 weeks, CD8/CD28null T cells were significantly increased in the airway with a trend for an increase in lung tissue and blood. Increased production of proinflammatory cytokines and expression of alternative co-stimulatory molecules by CD8/CD28null T cells may play a role in inflammatory or autoimmune responses in COPD and identify therapeutic targets.

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The Index of Receptivity to Tobacco Industry Promotion (IRTIP) is a model that is used by hundreds of articles. The causal claim based on findings from this model is even more pervasive, and has resulted in much of the modern post 1998 tobacco legislation that is still enforced. This thesis tested the link between adolescent receptivity to tobacco industry promotion and susceptibility to smoking. Pierce et al. (1998) reported that they had found a positive and causal association between receptivity and susceptibility by using IRTIP. They claimed that receptivity to tobacco industry promotion was the only significant causal factor affecting adolescent susceptibility to smoking. Exposure to peer and parental smoking was not found to be a significant effect. A review of the literature found that many sections of IRTIP differ from accepted marketing theory on how cigarette advertising and promotions affect adolescent adoption of cigarette smoking. The proxy measures used in IRTIP were shown to diverge from those previously used for measuring the constructs of Attention, Intention, Desire and Action (AIDA) in marketing communications. IRTIP also differs from previous theory by including measures that attempt to quantify the effect of tobacco premiums into a model that was designed to measure the effects of advertising.

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RATIONALE: Exercise has been shown to attenuate cigarette cravings during temporary smoking abstinence; however, the mechanisms of action are not clearly understood. OBJECTIVES: The objectives of the study were to compare the effects of three exercise intensities on desire to smoke and explore potential neurobiological mediators of desire to smoke. METHODS: Following overnight abstinence, 40 participants (25 males, 18-59 years) completed three 15 min sessions of light-, moderate-, or vigorous-intensity exercise on a cycle ergometer in a randomized crossover design. Ratings of desire to smoke were self-reported pre- and post-exercise and heart rate variability was measured throughout. Saliva and blood were analyzed for cortisol and noradrenaline in a sub-sample. RESULTS: Exercise influenced desire to smoke (F [2, 91] = 7.94, p < 0.01), with reductions greatest immediately after vigorous exercise. There were also significant time x exercise intensity interaction effects for heart rate variability and plasma noradrenaline (F [8, 72] = 2.23, p = 0.03), with a bias in noradrenaline occurring between light and vigorous conditions (adjusted mean difference [SE] = 2850 ng/ml [592], p < 0.01) at 5 min post-exercise. There was no interaction of time x exercise intensity for plasma and salivary cortisol levels. CONCLUSIONS: These findings support the use of vigorous exercise to reduce cigarette cravings, showing potential alterations in a noradrenergic marker.

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RATIONALE: Smoking cessation is associated with cigarette cravings and tobacco withdrawal symptoms (TWS), and exercise appears to ameliorate many of these negative effects. A number of studies have examined the relationships between exercise, cigarette cravings, and TWS. OBJECTIVES: The objectives of this study were (a) to review and update the literature examining the effects of short bouts of exercise on cigarette cravings, TWS, affect, and smoking behaviour and (b) to conduct meta-analyses of the effect of exercise on cigarette cravings. METHODS: A systematic review of all studies published between January 2006 and June 2011 was conducted. RESULTS: Fifteen new studies were identified, 12 of which found a positive effect of exercise on cigarette cravings. The magnitude of statistically significant effect sizes for 'desire to smoke' and 'strength of desire to smoke' ranged from 0.4 to 1.98 in favour of exercise compared to passive control conditions, and peaked either during or soon after treatment. Effects were found up to 30 min post-exercise. Cigarette cravings were reduced following exercise with a wide range of intensities from isometric exercise and yoga to activity as high as 80-85 % heart rate reserve. Meta-analyses revealed weighted mean differences of -1.90 and -2.41 in 'desire to smoke' and 'strength of desire to smoke' outcomes, respectively. Measures of TWS and negative affect were reduced following light-moderate intensity exercise, but increased during vigorous exercise. CONCLUSIONS: Exercise can have a positive effect on cigarette cravings and TWS. However, the most effective exercise intensity to reduce cravings and the underlying mechanisms associated with this effect remain unclear.

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Socio-economic status (SES) has a strong influence on cigarette smoking behaviour. However, as a more sensitive and realistic index of SES, family average income (FAI) has little studied regarding its association with smoking. With a response rate of 90.1%, a cross-sectional study was conducted among randomly selected urban-rural participants (n  = 29,353) between October of 2000 and March of 2001 in Nanjing, China. The proportion of male participants who were current smokers was 54.7%; for females it was 2.2%. After adjustment for possible confounding variables (area of residence, age, education, occupation) males in the middle (OR 0.76; 95% CI 0.69–0.84) and higher (OR 0.64; 95% CI 0.57–0.71) FAI tertiles had lower odds of being smokers than did males in the lower FAI tertile. There were no differences by FAI category in the odds of being an ex-smoker. Therefore, current smoking among adult males is inversely associated with family average income in a regional Chinese population. FAI may inform the targeting of campaigns or other initiatives, particularly in populations where material prosperity is low in some social groups.

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I read the recent comments on Pope Paul VI and the 'smoke of Satan' (July AD2000) with interest not long after I had finished re-reading the massive work by the late Archbishop Annibale Bugnini, generally considered to be the main architect of the liturgical reforms prior to, during, and after Vatican II.