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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Prevalência da asma e sintomas respiratórios no município de Vitória (ES): comparação entre duas áreas com diferentes fontes de poluição atmosférica identificadas através do biomonitoramento / Asthma and Respiratory Symptoms in Vitoria, Brazil: Comparing two areas with different air pollution sources profiles throughout biomonitoring

Dione da Conceição Miranda 28 August 2008 (has links)
Introdução: Atribui-se à poluição atmosférica aproximadamente 800 mil mortes prematuras anualmente ao redor do mundo, sendo que diversos estudos têm mostrado que mesmo quando as emissões dos poluentes estiveram em conformidade com os padrões estabelecidos, mudanças dos níveis de poluição em curtos períodos, sazonalmente, ou em longo prazo produziram efeitos nocivos sobre a saúde das populações expostas. Dentre estas populações, idosos e crianças foram os mais sensíveis a esses efeitos. Vitória é uma cidade industrial que tem enfrentado um aumento da sua frota automotiva e, conseqüentemente, um aumento das concentrações dos poluentes atmosféricos. O presente trabalho comparou a prevalência de sintomas respiratórios em escolares expostos predominantemente aos poluentes atmosféricos emitidos por indústrias e por veículos automotores. Casuística e Métodos: Estudo transversal, exploratório, em uma amostra de 350 crianças em duas escolas localizadas em áreas com diferentes fontes predominantes de poluição atmosférica (industrial e automotiva). As fontes predominantes de poluição atmosférica em cada área foram identificadas através da análise de componentes principais, tendo como base os componentes químicos identificados em folhas de Tradescantia pallida expostas através da técnica de fluorescência de Raio-X. Foi aplicado o questionário International Study of Asthma and Allergies in Childhood (ISAAC) para investigar os sintomas respiratórios. Outros sintomas e condições de moradia foram avaliados através de um questionário complementar. A associação entre a freqüência dos sintomas entre as áreas foi investigada através do teste de Qui-quadrado. Modelos de regressão logística foram usados para os cálculos das razões de chances prevalentes (OR). Resultados: Não houve associação significativa nas prevalências dos sintomas pesquisados entre as áreas investigadas. Em relação às morbidades referidas, rinite mostrou uma associação significativa com local de moradia próxima à área industrial, OR= 2 (IC95%: 1,1; 3,7). Embora não tenham sido encontradas associações, asma, tosse e coriza também foram mais freqüentes nas crianças moradoras na área industrial. Conclusão: Os resultados encontrados na cidade de Vitória sugerem que o risco de exposição às emissões industriais pode ser maior que o da emissão por fontes automotivas / Introduction: Almost 800 thousand premature deaths have been attributed to the air pollution around the world, and several studies have showed that even when the established patterns for pollutants emissions were achieved, short and seasonal changes in the pollutant levels, or long term changes may lead to a different harmful health effects on the exposed population. The elderly and children have been identified the most susceptible groups in terms of air pollution health effects. Vitória is a seaboard Brazilian industrial city, which has faced an increase in the automotive fleet in the last decade, and, consequently, air pollution levels. Casuistic and methods: This study compared the prevalence of respiratory symptoms in school children exposed, mainly, to industrial or automotive sources. We carried out a cross sectional study with 350 children of two schools located in different areas. The main source of air pollution in each area was assessed by factor analysis based on components identified in Tradescantia pallid leafs through fluorescence x-ray technique. The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was applied to investigate respiratory symptoms. Referred respiratory morbidity was also investigated. Associations between areas and frequency of symptoms were tested with the chi-square test. Logistic regression models were used to calculate the prevalent odds ratio (OR) of the main respiratory symptoms. Results: There was no significant association between area and prevalence of respiratory symptoms. In terms of referred disease, rhinitis was associated with living in the industrial area, OR= 2 (CI95%:1.1; 3.7). Although without significant statistical association, asthma, cough and flue were also more frequent among those living in the industrial area. Conclusion: Despite the increase of automotive contribution to the pool of air pollutants in the city of Vitória, our results suggest that, in this specific situation, being exposed to industrial emissions may be more hazardous than being exposed to automotive emissions
32

Twin Faces! Vitamin E and Respiratory and Atopic Diseases

Veeranki, Sreenivas P., Cao, Yan, Zheng, Shimin 01 September 2014 (has links)
Purpose To estimate susceptibility to smoking among never-smoking youth globally and identify factors associated with such behavior. Methods Cross-sectional data for 168 countries were obtained from the Global Youth Tobacco Survey. Simple and multiple logistic regression analyses were conducted. Frequencies and proportions for descriptive statistics, and adjusted odds ratios with 95% confidence intervals for logistic regression models were reported. Results Approximately 12.5% of never-smoking youth worldwide were susceptible to smoking worldwide, of which 7.2% were males and 5.3% were females. Compared with youth in the Americas, those in other WHO regions were associated with decreased susceptibility to smoking. Regardless of gender, exposure to parental or peer smoking, secondhand smoke inside or outside home, and tobacco industry promotion was associated with increased smoking susceptibility. In contrast, support for smoke-free policies and school antismoking education was associated with decreased susceptibility to smoking among females. Moreover, exposure to antismoking media messages was associated with increased susceptibility to smoking among never-smoking youth. Conclusions Approximately 1 in 8 never-smoking youth worldwide was found to be susceptible to smoking. A comprehensive approach involving parental and peer education, smoke-free policies, ban on tobacco advertising and promotions, and antismoking education in schools should be developed by policy makers and public health professionals to protect never-smoking youth from being susceptible to smoking and transforming into future regular smokers.
33

House dust endotoxin: associated respiratory outcomes and effectiveness of environmental interventions

Mendy, Angelico 01 January 2018 (has links)
Background: Endotoxin is a lipopolysaccharide located on the outer membrane of the cell wall of Gram-negative bacteria that is widespread in the environment. Although domestic endotoxin has been found to be associated with asthma and wheeze, its association with chronic obstructive pulmonary disease (COPD) is unclear. It is also unknown how environmental exposures influence the relationship between endotoxin and asthma and very few studies have investigated the effectiveness of interventions in reducing endotoxin in the homes of people with asthma. Goals: The goals of this dissertation were to examine 1) the association of house dust endotoxin with chronic bronchitis or emphysema, two phenotypes of COPD, 2) the influence on the relationship between endotoxin and asthma outcomes of environmental factors such as exposure to dog and cat in homes, climate regions, as well as co-exposure to ambient air pollution, and 3) the effectiveness of an environmental intervention in reducing home endotoxin and asthma symptoms in rural Iowa children with asthma. Methods: For the first two goals of this dissertation, data from the 2005-2006 National Health and Nutrition Examination Survey (NHANES) was used. Dust sampled from the bedroom floor and bedding of 6,963 children and adult participants was evaluated for endotoxin at the University of Iowa Pulmonary Toxicology facility using a kinetic chromogenic Limulus amebocyte lysate assay. Data on asthma outcomes and chronic bronchitis or emphysema (CBE) was collected using questionnaires. Home exposure to dog and cat was considered by pet ownership and levels of dog (Canis familiaris 1) and cat (Feline domesticus 1) allergens in house dust. Annual average particulate matter ≤2.5 µm (PM2.5), ozone (O3), and nitrogen dioxide (NO2) concentrations at participants’ residential location were estimated using the Community Multiscale Air Quality (CMAQ) and Downscaler (DS) models. In the third goal, data from the Louisa Environmental Intervention Project (LEIP) study which included schoolchildren 5-14 years-old with active asthma from Louisa and Keokuk counties in rural Iowa was analyzed. The households were block-randomized to receive extensive (education + professional cleaning) or educational intervention. Environmental sampling and questionnaire administration were done at baseline and during three follow-up visits. Results: In the NHANES, the median concentration of endotoxin in house dust was 16.2 EU/mg. In adjusted analysis, house dust endotoxin (log10-endotoxin) was associated with increased odds of CBE diagnosis (OR: 1.27, 95% CI: 1.00-1.61) and chronic bronchitis symptoms (OR: 1.78, 95% CI: 1.01-3.12). Sensitization to inhalant allergens modified the relationship between log10-endotoxin and CBE diagnosis (P(interaction)=0.001), with stronger associations observed in sensitized participants (OR: 2.46, 95% CI: 1.72-3.50). The association of endotoxin with asthma outcomes was different with climate regions of the U.S. Endotoxin was associated with higher prevalence of wheeze outcomes in the past 12 months in subarctic/very cold/cold regions (OR: 1.48, 95% CI:1.19-1.85) and in hot-humid regions (OR: 1.66, 95% CI:1.04-2.65). In hot-humid regions, endotoxin was positively associated with current asthma (OR: 1.56, 95% CI:1.11-2.18), but negatively with sensitization to any inhalant allergens (OR: 0.83, 95% CI:0.74-0.92). Exposure to dog and cat allergens enhanced endotoxin association with current asthma (OR: 2.00, 95% CI: 1.04-3.83, P(interaction)=0.012) and wheeze in the past 12 months (OR: 1.88, 95% CI: 1.32-2.66, P(interaction)=0.016). House dust endotoxin co-exposure with PM2.5 (CMAQ) was synergistically associated with emergency room visits for asthma in the past 12 months (OR: 5.01, 95% CI: 2.54-9.87) in general. In children, a synergistic association was found for co-exposure to house dust endotoxin and NO2 with the outcome (OR: 3.45, 95% CI: 1.65-7.18). In LEIP, 104 asthmatic children from 89 homes were included in the study. In the main analysis, extensive compared to the educational intervention was associated with decreased endotoxin load in farm homes (P-value of main effect for intervention <0.0001) and with less frequent nighttime asthma symptoms (Intervention x visit interaction P-value = 0.044). In exploratory analysis, endotoxin load reduction from baseline was associated with less daytime wheeze (OR: 0.59, 95%CI: 0.38-0.91) and daytime cough (OR: 0.62, 95% CI: 0.40-0.97). Conclusions: House dust endotoxin is associated with obstructive pulmonary diseases. The association of endotoxin with asthma outcomes is stronger in cold regions of the U.S. and is enhanced by exposure to pet allergens and co-exposure to ambient air pollutants such as PM2.5 and NO2 in children. The LEIP study demonstrated that extensive cleaning interventions can be effective at reducing endotoxin in the homes children with asthma and can alleviate their symptoms.
34

The effects of passive smoking on respiratory illness in early childhood in Shanghai, P.R.China

Jin, Cui 15 January 1993 (has links)
The effects of household exposure to cigarette smoke on the incidence of respiratory illness were examined among 1007 18 month old children at Lu-wan District, Shanghai City, People's Republic China. The passive smoking quantity was estimated by summing the total daily cigarette consumption of family members. No mothers who smoked were found. A significant dose-response relationship of passive smoking to hospitalization for respiratory illness during the children's first 18 months of life was found, for which no confounding factors were discovered. The relative risk was 2.4 for children living in families including people who smoked 20 or more cigarettes a day compared with those living in nonsmoking families. The children who were boys or artificially (bottle) fed were more affected than those who were girls or breast fed. The cumulative incidence of bronchitis and pneumonia increased significantly with increasing cigarette smoking of family members, that did not change when sex, birth weight, type of feeding, coal for cooking, or parental education were taken into account. Family smoking status was not found to be significantly associated with the cumulative incidence of asthma, whooping cough, sinusitis or measles. / Graduation date: 1993
35

Quality of life in children with chronic allergic respiratory disease: a population-based child health survey inHong Kong

古修齊, Koo, Sergio, Don. January 2009 (has links)
published_or_final_version / Community Medicine / Master / Master of Public Health
36

Nutritional status and bronchopulmonary dysplasia (BPD)

Chehade, Joyce P. January 1994 (has links)
The present study was performed to determine whether ongoing oxidative stress in some BPD infants contributes to their increased energy expenditure leading to growth failure. The study consisted of two parts. The first is a descriptive census of BPD infants (n = 38) followed at the outpatient clinics at The Montreal Children's Hospital (MCH). The second is a cross-sectional study of fifteen patients wherein anthropometric parameters, energy intake, and oxidative stress measures (red cell glutathione (GSH) and plasma malondialdehyde (MDA)) were assessed. Nine infants with growth failure were compared to six thriving infants with respect to their nutritional and oxidative stress status. Growth failure was defined as weight for age and weight for height for age less than the tenth percentile (z score $ leq - 1).$ Results revealed that the prevalence of growth failure in the BPD infants followed at MCH ranged between 45% and 55%. The mean ($ pm$ SD) energy intakes for thriving and failing to thrive infants expressed as a percent of the recommended nutrient intake were 104 $ pm$ 46% and 133 $ pm$ 35% respectively. Six infants had reduced mean ($ pm$ SD) blood glutathione per hemoglobin (3.63 $ pm$ 0.37 umol/g) compared to adult controls (6.57 $ pm$ 1.04 umol/g). Four of the six infants had growth failure while two were thriving. Fourteen Infants including all failing to thrive infants had elevated mean ($ pm$ SD) plasma MDA levels compared to adult controls (129 $ pm$ 48 vs 55 $ pm$ 3 nmol/l). Differences in oxidative stress markers were not observed between the two groups. These results suggest that growth failure is associated with an increase in caloric consumption and not with a decrease in caloric intake. The preliminary findings on oxidative stress markers suggest a depletion of the GSH antioxidant in some infants and marked lipid peroxidation in the BPD population.
37

Calcium, vitamin D and vitamin A metabolism in cystic fibrosis: implictions of gender differences and disease severity

Greer, R. M. Unknown Date (has links)
No description available.
38

Multiplex reverse transcription-PCR for detection and identification of human parainfluenza viruses 1,2,3 and 4 infection in hospitalized children with respiratory disease in Hong Kong /

Lam, Siu-yan, January 2007 (has links)
Thesis (M. Med. Sc.)--University of Hong Kong, 2007.
39

Exposure assessment of traffic-related pm10 pollution in outdoor play areas of early childhood centres a thesis submitted to Auckland University of Technology in fulfilment of the requirements for the degree of Master of Philosophy (MPhil), 2008.

Lyne, Mark. January 2008 (has links)
Thesis (MPhil) -- AUT University, 2008. / Includes bibliographical references. Also held in print (xiii, 166 leaves : ill. ; 30 cm.) in the Archive at the City Campus (T 363.7392 LYN)
40

Vitamin A status and inflammation during the first week of life in extremely premature infants at risk for bronchopulmonary dysplasia

Mentro, Anne M., January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xiv, 133 p.; also includes graphics (some col.) Includes bibliographical references (p. 107-133). Available online via OhioLINK's ETD Center

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