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Alterations in Tight Junctional Proteins and Their Effects on Pulmonary InflammationLewis, Joshua B. 01 March 2017 (has links)
The lungs represent one of the earliest interfaces for pathogens and noxious stimuli to interact with the body. As such, careful maintenance of the permeability barrier is vital in providing homeostasis within the lung. Essential to maintaining this barrier is the tight junction, which primarily acts as a paracellular seal and regulator of ionic transport, but also contributes to establishing cell polarity, cell-to-cell integrity, and regulating cell proliferation and differentiation. The loss of these tight junctions has been documented to result in alterations in inflammation, and ultimately the development of many respiratory disorders such as COPD, Asthma, ARDS, and pulmonary fibrosis. One critical contributor that creates this permeability barrier is the tight junctional protein Claudin. While studies have begun to elucidate the various functions and roles of various Claudins, our understanding is still limited. To initially investigate these proteins, we looked at both temporal and spatial expression patterns for family members during development. A consistent pattern was demonstrated in mRNA expression for the majority of Claudin members. In general, Claudin expression underwent rapid increase during time periods that correlate with the pseudoglanduar/canalicular periods. One notable exception was Claudin 6 (Cldn6), which demonstrated decreasing levels of mRNA expression throughout gestation. We also sought to understand expression dynamics during the addition of maternal secondhand smoke (SHS) which resulted in an almost universal decrease in Claudin proteins. To more fully explore expression mechanisms that affect Claudin-6 (Cldn6), we exposed pulmonary alveolar type II (A549) cells to cigarette smoke extract (CSE) and found that it transcriptionally regulated Cldn6 expression. Using a luciferase reporter, we determined that transcription was negatively regulated at multiple promoter response elements by CSE, and transcription was equally hindered by hypoxic conditions. These findings identified Cldn6 as a potential target of SHS and other respiratory irritants such as diesel particulate matter (DPM). We next sought to assess whether an increase in Cldn6 was sufficient to provide a protective advantage against harmful exogenous exposure. To test this, we utilized a doxycycline induced Cldn6 over-expressing mouse, and subjected it to SHS for 30 days to stimulate an inflammatory state. Our findings demonstrated that Cldn6 transgenic animals have decreased inflammation as evidence by decreased total cell infiltration into the airways, decreased polymorphonuclocyte (PMNs) extravasation, total protein in bronchoalveolar lavage fluid (BALF), and decreased cytokine secretion. Anti-inflammatory advantages were also discovered during experiments involving acute exposure to DPM. In both cases, while stimulation of transgenic mice with SHS or DPM diminished Cldn6 expression, anti-inflammatory evidence emerged suggesting that genetic up-regulation of Cldn6 likely causes the recruitment of other tight junctional components during an organism's response to environmental assault.
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Climatology and Variability of Aerosol over Africa, the Atlantic, and the AmericasAdams, Aaron M 07 July 2011 (has links)
Using Vertical Feature Mask (VFM) data from Cloud - Aerosol Lidar Infrared Pathfinder Satellite Observations (CALIPSO), I have documented 3-dimensional (3D) structures in occurrence probabilities of aerosol over a broad region of Africa, the Atlantic, Europe, and Americas. The 3D structures illustrate the seasonal means and seasonal cycle in the zonal and meridional variability of the vertical profiles of mineral dust, biomass burning smoke, and polluted dust (external mixture of dust and smoke), and their emissions sources and transport pathways. Emission sources vary by geographical location. The persistent Saharan dust source is evident throughout the year and observed and recorded by CALIPSO 70-80% of the time over Africa. Horizontal and vertical occurrence of dust is variable in time with maximum heights and westward transport occurring in boreal summer and minimum heights and transport occurring in boreal winter. The southern African biomass burning source is also evident throughout the year, through westward transport over the Atlantic is only evident in boreal summer and fall; mixing with dust over the continent limits westward transport of pure smoke to the continent in winter and spring. Other smaller smoke and dust sources are discussed. The role of the Inter-Tropical Convergence Zone (ITCZ) in limiting the southward transport of dust and northward transport of smoke over Africa is demonstrated. Surprisingly, the highest probability of polluted dust is found in the ITCZ, even though the probabilities of dust and smoke are low. Wind trajectories reveal smoke of southern African origin is transported northward at the lower levels, but rarely penetrating through ITCZ rainband while Saharan dust is transported southward at higher levels, crossing the ITCZ frequently. This quasi-circulation of aerosol is shown to be the mixing mechanism of dust and smoke into polluted dust in the area of the ITCZ.
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A population-based, case-control study of lung cancer and indoor air pollution among nonsmoking women living in Shanghai, ChinaZhong, Lijie. January 1998 (has links) (PDF)
Thesis (Ph.D.)--McGill University (Canada), 1998. / Adviser: Mark Goldberg. Includes bibliographical references.
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Changes in Georgia Restaurant and Bar Smoking Policies Between 2006 and 2012Chandora, Rachna D 17 May 2013 (has links)
Introduction: The purpose of this study is to examine the change in smoking policy status among bars and restaurants since the Georgia Smokefree Air Act of 2005 was implemented and identify restaurant and bar characteristics that are associated with allowing smoking.
Methods: Data was obtained from similar Georgia indoor air surveys conducted in 2006 and 2012. Both surveys were designed to gather information about restaurant and bar smoking policies and examine owner and manager perceptions of the Georgia Smokefree Air Act. Descriptive analysis and paired sample t-tests were performed to identify changes in smoking policy status and other variables over time. Chi-square and logistic regression analysis were used to test for significant associations between establishment smoking policy status and other characteristics.
Results: The percent of restaurants and bars in Georgia allowing smoking nearly doubled from 9.2% in 2006 to 18.2% in 2012. The analysis showed a statistically significant increase in the percentage of establishments allowing smoking when minors are present. After adjusting for the effects of other variables, three variables were significant predictors of allowing smoking: having seats for drinking outdoors, having a liquor license, and generating greater than or equal to 25% of gross sales from alcohol.
Conclusions: The Smokefree Air Act was enacted to protect the health and welfare of Georgia citizens, but the percentage of establishments allowing smoking has risen since it was implemented. These results suggest that policy makers should reevaluate the law and consider strengthening it to make restaurants and bars 100% smokefree without exemptions.
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On the Potential Use of Small Scale Fire Tests for Screening Steiner Tunnel Results for Spray Foam InsulationDidomizio, Matthew 05 1900 (has links)
The goal of this study is to assess the potential of using bench-scale fire testing to screen materials for the Steiner tunnel fire test. It is hypothesized that the chemical and physical changes made to a material to improve its fire performance in small scale fire tests will have a predictable response in the Steiner tunnel. This hypothesis is based on the observation that fire test results can, in some cases, provide insight on a material's relative fire hazard, and the assumption that the relative hazard should be consistent across scale.
The ASTM E84 Steiner tunnel test provides a relative ranking of material hazard in two categories. The horizontal Flame Spread Index (FSI) is used to rank the flame hazard of a material, and the Smoke Developed Index (SDI) is used to rank the smoke hazard of a material. Two fire tests are proposed to independently assess each hazard at the bench-scale. The ASTM E1354 cone calorimeter test measures a material's open-flaming heat release rate; it is proposed that the cone calorimeter test can be used to assess a material's relative flame hazard. The ISO 5659-2 smoke density chamber test measures a material's closed-environment smoke development; it is proposed that the smoke density chamber test can be used to assess a material's relative smoke hazard.
The material selected for this study is fire-retarded sprayed polyurethane foam (FRSPF) insulation. Specific details of the foam chemistry, fire retardants, and the manufacturer are confidential. Generally, the foam can be described as medium-density (approximately 2 lbs/ft³), closed-celled, and semi-rigid. The fire retardant additives are comprised of differing ratios and concentrations of phosphorous- and halogen-containing compounds.
A series of 30 Steiner tunnel tests is conducted on 20 different formulations. Repeated testing is conducted on several formulations in order to assess variability in the Steiner tunnel test results. Cone calorimeter and smoke density chamber tests are conducted on a subset of those formulations, in sets of 3-5 tests per formulation.
Key performance indicators are identified from each fire test, relationships between those indicators are examined, and correlations are presented where strong relationships are apparent. Empirical prediction models are proposed for FSI and SDI based on the success rate of prediction, and minimization of error between experimental (measured) and modelled (predicted) results. It is concluded that for the materials tested in this study, there is sufficient evidence of consistency in relative performance to recommend bench-scale screening tests as a cost-effective alternative to repeated Steiner tunnel testing.
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The social environment is most important for not using snus or smoking among adolescentsEdvardsson, Ingrid, Lendahls, Lena, Andersson, Tobias, Ejlertsson, Göran January 2012 (has links)
Aims: To identify factors, which were related to being smoke-free and snus-free, respectively, among adolescents in relation to adolescents who were smoking and/or using snus, and de-termine if there were any sex differences. Me- thods: A questionnaire study was performed among students in year two in upper secondary schools (17-years-old) in southern Sweden in 2009. More than 2200 students completed the questionnaire regarding health and living habits anonymously. The variables were tested by χ²-test, before selection into the logistic model. Because of the salutogenic approach in the study, the results of the logistic regression analyses were expressed as Positive Odds Ratio (POR). Results: The prevalence of being smoke- free was 75.6 percent for girls and 70.2 percent for boys, whilst the prevalence of being snus- free was 95.1 percent for girls and 70.2 percent for boys. Having a tobacco-free best friend was the most important factor that correlated with being smoke- and snus-free as an adolescent, for both boys and girls. Good living habits, such as drinking less alcohol, were also central to being smoke-free and snus-free. Conclusions: The results show that a tobacco-free environ-ment has a great influence on whether or not adolescents stay tobacco-free. As the environ-ment has a big impact, the school has a big challenge to work with the school environment and policies but also with family responsibility, norms and attitudes to tobacco.
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Mechanisms of environmental tobacco smoke and benzo[a]pyrene induced cardiovascular injury and the protective role of resveratrolAl-Dissi, Ahmad 21 March 2011
Despite extensive research, the mechanisms behind cardiovascular effects of subchronic environmental tobacco smoke (ETS) remain unclear, but may be related to ETS-induced inflammation and oxidative stress. Additionally, the protective role of resveratrol (RES), a natural antioxidant available in red grapes, is controversial. We hypothesized that the polycyclic aromatic hydrocarbon (PAH) component of ETS is responsible for causing adverse cardiovascular effects. We also hypothesized that the administration of RES is protective against the adverse cardiovascular effects of ETS. In order to address these hypotheses, male juvenile pigs (4-weeks old) were exposed to ETS or ambient air for 28 consecutive days (1 hr/day) and effects compared to 7 days of i.v. injection of the PAH, benzo-a-pyrene (BAP; 5 mg/kg daily). In another experiment, pigs were sham-exposed or ETS-exposed, with or without oral RES treatment (5mg/kg daily). In all experiments, endothelial and left ventricular function were assessed by flow mediated dilation (FMD), and echocardiography, respectively, while blood pressure was evaluated by oscillometry. At the termination of each experiment, serum nitrotyrosine, total nitrate/nitrite (NOx) and C-reactive protein (CRP) were measured as well as hepatic and pulmonary ethoxyresorufin-o-deethylase (EROD) activity to indicate cytochrome P450 1A1 (CYP1A1) expression. Finally, the correlation between pulmonary inflammation and adverse cardiovascular effects was investigated by measuring total and differential white blood cell (WBC) count as well as leukocyte elastase activity in bronchoalveolar lavage fluid at the termination of each experiment. ETS exposure, but not BAP treatment, resulted in a significant impairment of FMD (P<0.0001) and increased left ventricular end diastolic volume (P=0.0032). Cotreatment with RES failed to restore the ETS induced impairment of FMD (P>0.05). However, a trend pointing to an increase in ejection fraction (EF) was noted (P=0.072). ETS, BAP and RES treatments failed to have any effect on blood pressure (P>0.05). BAP injection caused a significant increase in serum nitrotyrosine (P=0.0146) and CRP (P=0.012), but not serum NOx levels (P>0.05). In contrast, ETS exposure resulted in a significant increase in CRP serum levels (P=0.0092), a trend pointing to increased serum nitrotyrosine (P=0.105), and no change in serum NOx levels (P>0.05). The increased nitrotyrosine and CRP with ETS exposure was not reversed by RES administration (P>0.05). ETS exposure increased EROD activity in the lung (P=0.0093), but not the liver (P=0.12). In contrast, BAP treatment had the opposite effect (lung EROD: P=0.621, liver EROD: P=0.01), while RES administration had no effect (P>0.05). ETS exposure (P=0.0139), but not BAP treatment (P=0.723), resulted in increased WBC count in BAL fluid which was not affected by RES administration (P>0.05). These results show that ETS exposure causes lung inflammation, systemic inflammation, oxidative stress-mediated inactivation of nitric oxide and impaired endothelial function. In contrast, BAP failed to alter endothelial function, downstream of the lung, despite systemic inflammation and increased oxidative stress. Furthermore, RES failed to restore endothelial function, or decrease systemic inflammation and oxidative stress. Taken together, these results suggest either that pulmonary inflammatory responses or pulmonary increases in CYP1A1 activity may be more important links to endothelial dysfunction than systemic inflammation and nitric oxide bioactivity. The beneficial effects of RES by itself are manifested only at the cardiac level by improving the ejection fraction, but the work in this thesis failed to detect any ability of RES to ameliorate ETS cardiovascular effects.
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Beliefs and behaviors related to environmental tobacco smoke (ETS) exposure in the home : cultural differences between francophones and the rest of the Canadian populationZhu, Tong 03 January 2006
This study explored how cultural heritage might affect peoples beliefs, attitudes, and behaviors toward Environmental Tobacco Smoke (ETS), which in turn affected actual ETS exposure. It used data from the 2001 National Survey on Environmental Tobacco Smoke in the Home. It compared two cultural groups: Francophones and the rest of the Canadian population (RCP), and found that Francophone nonsmokers had a significantly higher ETS exposure than the RCP (19.3% vs. 8.5%). The difference was much greater than the difference in smoking prevalence for the two groups (26.2% vs. 22.4%). </p>The study found Francophones scored lower than the RCP in almost every aspect of ETS-related beliefs, attitudes, and behaviors. They were less likely to believe ETS to be harmful and less supportive of ETS-control policies. They were less likely to have done something that reduced ETS exposure at home. In both cultural groups, smokers scored lower than nonsmokers in ETS-related beliefs and attitudes. However, the difference between the two groups remained significant even if the comparisons were done within smokers and nonsmokers. </p>The most significant finding of the study was that Francophones were more likely to trust those so-called ETS-reduction strategies that appeared to be effective but were not in reality (e.g., opening the window when someone smokes). Moreover, there was a statistically significant interaction between smoking status and cultural heritage: fewer nonsmokers than smokers within each cultural group believed that these strategies were really effective, but the difference between the nonsmokers and smokers was significantly smaller for Francophones than that for the RCP. Therefore, the tendency to trust ineffective ETS-reduction strategies, especially among the nonsmokers, explained why Francophones were significantly less likely to adopt strategies that would actually reduce ETS exposure. </p>These results suggest that in order to move ETS policies forward and to effectively reduce ETS exposure among Canadian nonsmokers, the key strategy is to mobilize the nonsmokers to be less tolerant of ETS and more persistent in only allowing smoking to occur outdoors. This will not only help protect nonsmokers from the harm of ETS, but will eventually help smokers to quit smoking.
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Tecken : En retorisk-semiologisk analys av antirökreklamExadaktilos, Kiriakos January 2011 (has links)
This essay studies how advertisements in various anti-smoking campaigns can influence and persuade by using anti-logos as counter-arguments to the tobacco industry's logos. In contrast to tobacco advertising arguments such as freedom (logos), pleasure (pathos) and trademark (ethos) the anti-smoking campaigns create anti-logos arguments with various connotations such as repulsive pictures and sexual implications to influence groups of people not to start smoking or to quit smoking. Advertisement of tobacco does not exist nowadays due to legal restrictions in the western world; however several decades of myths created in the consumer consciousness still exist. Thus one can speak of a tobacco advertising ideology that exists and the various anti-smoking campaigns trying to change that ideology. The purpose of anti-smoking campaigns is to conduct a kategoria of myth that tobacco advertisement has created over the years. Anti smoking organizations do this by creating a new ideology to affect consumer’s attitude toward smoking and the tobacco myth with an anti-myth. This becomes a counter-myth to the myth created by tobacco advertising and their logos and pathos arguments. The anti-smoke commercial logos become anti-logos and pathos to anti-pathos (antipathy) for the cigarette whose arguments are created from the viewer's connotations of anti-smoke commercials. The cigarette, as a product of connotations in commercials, shows how rhetorical persua-sion becomes public relations and vice versa.
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Rökfri arbetstid i Östhammars kommun : En intervjustudie av chefers upplevelserIsaksson, Lovisa, Lindahl, Christina January 2011 (has links)
Aim: To examine director’s experiences of the process to implement smoke-free working hours and also their need of support to make it feasible in the municipality of Östhammar. Method: A qualitative interview study with a descriptive design was used. Semi-structured interviews were made with six directors who were selected from different levels, localities and administrations in the municipality of Östhammar. A qualitative content analysis was used to analyze the data. Results: Many positive aspects were pointed out regarding the implementation of smoke-free working hours. The aspects of time and the support which had been offered to the smokers stood out among these. The majority of the directors considered that the support at the time of the implementation had been adequate. The difficulties that were experienced were mostly related to practical issues. Only a few proposals of support concerning the difficulties that had been experienced were presented. Two of the study’s participants had not experienced difficulties. Two positive effects of the policy were reduction in smoking or quitting smoking. Particularly one director stated that the policy did not function at all up to that point. The requested types of support in the future were continuing existing support, activities connected to the policy and a follow-up of the policy. Conclusion: The experiences of the informants were that the implementation process has functioned well with the exception of a few particular difficulties. Few proposals of support emerged in addition to already existing ones. Some form of activity connected to the policy or a follow-up of the policy is important to once again make it a pressing issue.
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