909 resultados para tobacco smoke


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Background/Aims: The effects of cigarette smoke (CS) on cyclosporine (CsA)-induced nephrotoxicity are poorly studied. This study aims to assess the effects of previous exposure to CS on CsA nephrotoxicity. Methods: Rats were either exposed to CS or sham (S) procedures for 10 min twice a day for 20 weeks. From the 16th to the 20th week, they received a low-salt diet. Beginning with the 17th week, they were given 2.5 mg/day CsA or vehicle (VH) for 3 weeks. The final groups were VH/CS, CsA/CS, VH/S, and CsA/S. On day 141, glomerular filtration rate (GFR), renal blood flow (RBF), renal vascular resistance (RVR), tubulointerstitial fibrosis, and CsA blood levels were measured and immunohistochemistry was analyzed for renal alpha-smooth muscle actin (SMA), nitrotyrosine, and vimentin. Results: CsA decrease in GFR was enhanced by CS exposure. CsA associated with CS induced higher periglomerular alpha-SMA and renal nitrotyrosine expression. CsA decreased RBF, but increased RVR, tubulointerstitial fibrosis, and alpha-SMA and renal vimentin expression. These changes and the CsA blood levels were not affected by CS exposure. Conclusion: CS aggravated the CsA-induced impairment of GFR and CS associated with CsA caused the development of periglomerular structural lesions and oxidative stress in a rat model of CsA nephrotoxicity. Copyright (C) 2012 S. Karger AG, Basel

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We evaluated the effects of cigarette smoke (CS) on lung inflammation and remodeling in a model of ovalbumin (OVA)-sensitized and OVA-challenged mice. Male BALB/c mice were divided into 4 groups: non-sensitized and air-exposed (control); non-sensitized and exposed to cigarette smoke (CS), sensitized and air-exposed (OVA) (50 mu g + OVA 1% 3 times/week for 3 weeks) and sensitized and cigarette smoke exposed mice (OVA + CS). IgE levels were not affected by CS exposure. The increases in total bronchoalveolar fluid cells in the OVA group were attenuated by co-exposure to CS, as were the changes in IL-4, IL-5, and eotaxin levels as well as tissue elastance (p < 0.05). In contrast, only the OVA + CS group showed a significant increase in the protein expression of IFN-gamma, VEGF, GM-CSF and collagen fiber content (p < 0.05). In our study, exposure to cigarette smoke in OVA-challenged mice resulted in an attenuation of pulmonary inflammation but led to an increase in pulmonary remodeling and resulted in the dissociation of airway inflammation from lung remodeling. (C) 2012 Elsevier B.V. All rights reserved.

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Recent systematic reviews concluded that the frequent consumption of fruits and vegetables is inversely associated with the risk of oral cancer. We assessed this association, specifically comparing results obtained to nonsmokers and smokers, as well to nondrinkers and drinkers. We conducted a case-control study involving 296 patients with oral squamous cell carcinoma (cases) attended in 3 major hospitals of Sao Paulo, Brazil, paired with 296 controls, recruited from outpatient units of the same hospitals. Multivariate models assessed the effect of fruits and salads according to smoking and drinking. The intake of fruit was associated with the prevention of the disease in the specific assessment among light [odds ratio (OR) = 0.46; 95% confidence interval (CI) = 0.27-0.78) and heavy (OR = 0.30; 95% CI = 0.14-0.65) smokers. The same was observed for vegetables consumption. For nonsmokers, no fruit (OR = 50; 95% CI = 0.22-1.12) or vegetable (for tomato, OR = 0.53; 95% CI = 0.31-0.93) was associated with reduced risk of oral and oropharyngeal cancer. Similar results were found in the stratified analysis according to drinking status with OR = 0.51 (95% CI = 0.30-0.87) and 0.18 for fruits (95% CI = 0.07-0.45), respectively, for light and heavy drinkers. This observation suggests that the protective effect of fruit and salad intake may modulate the deleterious effects from tobacco and alcohol.

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Background Tax policy is considered the most effective strategy to reduce tobacco consumption and prevalence. Tax avoidance and tax evasion therefore undermine the effectiveness of tax policies and result in less revenue for governments, cheaper prices for smokers and increased tobacco use. Tobacco smuggling and illicit tobacco trade have probably always existed, since tobacco's introduction as a valuable product from the New World, but the nature of the trade has changed. Methods This article clarifies definitions, reviews the key issues related to illicit trade, describes the different ways taxes are circumvented and looks at the size of the problem, its changing nature and its causes. The difficulties of data collection and research are discussed. Finally, we look at the policy options to combat illicit trade and the negotiations for a WHO Framework Convention on Tobacco Control (FCTC) protocol on illicit tobacco trade. Results Twenty years ago the main type of illicit trade was large-scale cigarette smuggling of well known cigarette brands. A change occurred as some major international tobacco companies in Europe and the Americas reviewed their export practices due to tax regulations, investigations and lawsuits by the authorities. Other types of illicit trade emerged such as illegal manufacturing, including counterfeiting and the emergence of new cigarette brands, produced in a rather open manner at well known locations, which are only or mainly intended for the illegal market of another country. Conclusions The global scope and multifaceted nature of the illicit tobacco trade requires a coordinated international response, so a strong protocol to the FCTC is essential. The illicit tobacco trade is a global problem which needs a global solution.

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The topic of tobacco smoking, in its several aspects, has been receiving increasing attention among researchers over the past few years, which has been reflected in more data and more solid scientific literature on the subject in national journals. This article aims to review the studies that focused on smoking published between January 2010 and June 2012, in Arquivos Brasileiros de Cardiologia (Brazilian Archives of Cardiology), Brazilian Journal of Medical and Biological Research, Clinics (Sao Paulo), Jornal Brasileiro de Pneumologia (Brazilian Journal of Pulmonology), Revista da Associacao Medica Brasileira (Journal of the Brazilian Medical Association) and Revista Brasileira de Cirurgia Cardiovascular (Brazilian Journal of Cardiovascular Surgery). During the aforementioned period 58 articles were published, 52 of which were original ones, addressing several aspects of smoking, such as effects on health, epidemiology, cessation and experimental studies.

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Abscisic acid (ABA) is an important regulator of plant responses to environmental stresses and an absolute requirement for stress tolerance. Recently, a third phytoene synthase (PSY3) gene paralog was identified in monocots and demonstrated to play a specialized role in stress-induced ABA formation, thus suggesting that the first committed step in carotenogenesis is a key limiting step in ABA biosynthesis. To examine whether the ectopic expression of PSY, other than PSY3, would similarly affect ABA level and stress tolerance, we have produced transgenic tobacco containing a fruit-specific PSY (CpPSY) of grapefruit (Citrus paradisi Macf.). The transgenic plants contained a single- or double-locus insertion and expressed CpPSY at varying transcript levels. In comparison with the wild-type plants, the CpPSY expressing transgenic plants showed a significant increase on root length and shoot biomass under PEG-, NaCl- and mannitol-induced osmotic stress. The enhanced stress tolerance of transgenic plants was correlated with the increased endogenous ABA level and expression of stress-responsive genes, which in turn was correlated with the CpPSY copy number and expression level in different transgenic lines. Collectively, these results provide further evidence that PSY is a key enzyme regulating ABA biosynthesis and that the altered expression of other PSYs in transgenic plants may provide a similar function to that of the monocot's PSY3 in ABA biosynthesis and stress tolerance. The results also pave the way for further use of CpPSY, as well as other PSYs, as potential candidate genes for engineering tolerance to drought and salt stress in crop plants.

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The aim of this study was to evaluate, histometrically, the bone healing of the molar extraction socket just after cigarette smoke inhalation (CSI). Forty male Wistar rats were randomly assigned to a test group (animals exposed to CSI, starting 3 days before teeth extraction and maintained until sacrifice; n=20) and a control group (animals never exposed to CSI; n=20). Second mandibular molars were bilaterally extracted and the animals (n=5/group/period) were sacrificed at 3, 7, 10 and 14 days after surgery. Digital images were analyzed according to the following histometric parameters: osteoid tissue (OT), remaining area (RA), mineralized tissue (MT) and non-mineralized tissue (NMT) in the molar socket. Intergroup analysis showed no significant differences at day 3 (p>0.05) for all parameters. On the 7th day, CSI affected negatively (p<0.05) bone formation with respect to NMT and RA (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, for the control and test groups, respectively). In contrast, no statistically significant differences (p>0.05) were found at days 10 and 14. It may be concluded that CSI may affect socket healing from the early events involved in the healing process, which may be critical for the amount and quality of new-bone formation in smokers.

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Programa de doctorado: Salud Pública (Epidemiología, Planificación y Nutrición)

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to compare the 10-year marginal bone loss rates around implants supporting single-unit crowns in tobacco smokers with and without a history of treated periodontitis.

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PURPOSE: The aim of the present study was to assess the oral mucosal health status of young male adults (aged 18 to 24 years) in Switzerland and to correlate their clinical findings with self-reported risk factors such as tobacco use and alcohol consumption. MATERIALS AND METHODS: Data on the oral health status of 615 Swiss Army recruits were collected using a standardised self-reported questionnaire, followed by an intraoral examination. Positive clinical findings were classified as (1) common conditions and anatomical variants, (2) reactive lesions, (3) benign tumour lesions and (4) premalignant lesions. The main locations of the oral mucosal findings were recorded on a topographical classification chart. Using correlational statistics, the findings were further associated with the known risk factors such as tobacco use and alcohol consumption. RESULTS: A total of 468 findings were diagnosed in 327 (53.17%) of the 615 subjects. In total, 445 findings (95.09%) were classified as common conditions, anatomical variants and reactive soft-tissue lesions. In the group of reactive soft-tissue lesions, there was a significantly higher percentage of smokers (P < 0.001) and subjects with a combination of smoking and alcohol consumption (P < 0.001). Eight lesions were clinically diagnosed as oral leukoplakias associated with smokeless tobacco. The prevalence of precursor lesions in the population examined was over 1%. CONCLUSIONS: Among young male adults in Switzerland, a significant number of oral mucosal lesions can be identified, which strongly correlate with tobacco use. To improve primary and secondary prevention, young adults should therefore be informed more extensively about the negative effects of tobacco use on oral health.

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The use of tobacco continues to be a substantial risk factor in the development and progression of oral cancer, periodontitis, implant failure and poor wound healing. Dental and dental hygiene education providers have made great advances towards the incorporation of tobacco education into their curricula in recent years. Unfortunately, however, both medical and dental education research has consistently reported schools providing only basic knowledge-based curricula that rarely incorporate more effective, behaviourally-based components affecting long-term change. The limited training of oral healthcare students, at least in part, is reflected in practising dental professionals continuing to report offering incomplete tobacco interventions. In order to prepare the next generation of oral healthcare providers, this paper proposes a paradigm shift in how tobacco use prevention and cessation (TUPAC) may be incorporated into existing curricula. It is suggested that schools should carefully consider: to what level of competency should TUPAC be trained in dental and dental hygiene schools; the importance of establishing rapport through good communication skills; the core knowledge level for TUPAC; suggested instructional and assessment strategies; the importance of continuing professional education for the enhancement of TUPAC.

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The purpose of this paper is to review the epidemiologic evidence for the effects of tobacco use and tobacco use cessation on a variety of oral diseases and conditions. Exposures considered include cigarette and bidi smoking, pipe and cigar smoking, and smokeless tobacco use. Oral diseases and disorders considered include oral cancer and precancer, periodontal disease, caries and tooth loss, gingival recession and other benign mucosal disorders as well as implant failure. Particular attention is given to the impact of tobacco use cessation on oral health outcomes. We conclude that robust epidemiologic evidence exists for adverse oral health effects of tobacco smoking and other types of tobacco use. In addition, there is compelling evidence to support significant benefits of tobacco use cessation with regard to various oral health outcomes. Substantial oral health benefits can be expected from abstention and successful smoking cessation in a variety of populations across all ages.

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Smoke spikes occurring during transient engine operation have detrimental health effects and increase fuel consumption by requiring more frequent regeneration of the diesel particulate filter. This paper proposes a decision tree approach to real-time detection of smoke spikes for control and on-board diagnostics purposes. A contemporary, electronically controlled heavy-duty diesel engine was used to investigate the deficiencies of smoke control based on the fuel-to-oxygen-ratio limit. With the aid of transient and steady state data analysis and empirical as well as dimensional modeling, it was shown that the fuel-to-oxygen ratio was not estimated correctly during the turbocharger lag period. This inaccuracy was attributed to the large manifold pressure ratios and low exhaust gas recirculation flows recorded during the turbocharger lag period, which meant that engine control module correlations for the exhaust gas recirculation flow and the volumetric efficiency had to be extrapolated. The engine control module correlations were based on steady state data and it was shown that, unless the turbocharger efficiency is artificially reduced, the large manifold pressure ratios observed during the turbocharger lag period cannot be achieved at steady state. Additionally, the cylinder-to-cylinder variation during this period were shown to be sufficiently significant to make the average fuel-to-oxygen ratio a poor predictor of the transient smoke emissions. The steady state data also showed higher smoke emissions with higher exhaust gas recirculation fractions at constant fuel-to-oxygen-ratio levels. This suggests that, even if the fuel-to-oxygen ratios were to be estimated accurately for each cylinder, they would still be ineffective as smoke limiters. A decision tree trained on snap throttle data and pruned with engineering knowledge was able to use the inaccurate engine control module estimates of the fuel-to-oxygen ratio together with information on the engine control module estimate of the exhaust gas recirculation fraction, the engine speed, and the manifold pressure ratio to predict 94% of all spikes occurring over the Federal Test Procedure cycle. The advantages of this non-parametric approach over other commonly used parametric empirical methods such as regression were described. An application of accurate smoke spike detection in which the injection pressure is increased at points with a high opacity to reduce the cumulative particulate matter emissions substantially with a minimum increase in the cumulative nitrogrn oxide emissions was illustrated with dimensional and empirical modeling.

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Introduction: Recent studies show that smoking prevalence in the Turkish-speaking migrant population in Switzerland is substantially higher than in the general population. A specific group treatment for Turkish-speaking migrants was developed and tested in order to provide the migrant population with equal access to smoking cessation programs and to improve the migration-sensitive quality of such programs by sociocultural targeting. Methods: The evaluation of the program included quantitative (questionnaires t1 and t2 and follow-up by telephone) and qualitative methods (participant observation and semi-structured interviews). Results: The results showed that 37.7% of the 61 participants were smoke free at the 12-month follow-up. The factors of being in a partnership and using nicotine replacement products during the program were positively associated with successful cessation. We also demonstrated the importance of “strong ties” (strong relationships between participants) and the sensitivity of the program to sociocultural (e.g., social aspects of smoking in Turkish culture, which were addressed in relapse prevention), socioeconomic (e.g., low financial resources, which were addressed by providing the course for free), and migration-specific (e.g., underdeveloped access to smoking cessation programs, which was addressed using outreach strategy for recruiting) issues. Conclusions: Overall, the smoking cessation program was successfully tested and is now becoming implemented as a regular service of the Swiss Public Health Program for Tobacco Prevention (by the Swiss Association for Smoking Prevention).

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In the recent years, for oral care in general, both improving oral hygiene and tobacco use cessation have been identified as necessary measures to gain and maintain long-term periodontal health. This growing evidence has given the dental team a whole new task to tackle when achieving and maintaining oral health with their patients. In order to support dental patients to quit tobacco use, it is helpful for the clinician to have a clear understanding of the genesis of 'tobacco use disease' in general. At present, the evidence-based method for tobacco use cessation consists of professional counselling on behavioural change using the so called "5A Method" (Ask, Advise, Assess, Assist and Arrange") in combination with pharmacotherapy. A suitable model for behavioural support in tobacco use cessation would help patients to move from one stage to the next. People who want to quit the smoking habit do not always participate in carefully controlled nicotine withdrawal programs, e.g. in linear fashion and from start to finish. Nevertheless, simple instructions - like those offered in the "Assist" (to help) and "Arrange" (to organize follow-up visits) - can be valuable tools for dental professionals supporting their patients to quit smoking. On the basis of significant evidence on the recovery of the oral mucosa and the periodontal tissue following tobacco use cessation, a new task has been emerged in dentistry: the role of oral health professionals providing counselling for patients who ought to quit tobacco use.