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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.
21

Land Use Random Forests for Estimation of Exposure to Elemental Components of Particulate Matter

Brokamp, Richard C. 02 June 2016 (has links)
No description available.
22

Spirometric reference equations for First Nations children and adolescents living in rural Saskatchewan

2016 February 1900 (has links)
Background: The spirometric reference values are of great importance for diagnosis and treatment of lung diseases. At present, there are no spirometric reference values for First Nations children and adolescents living in Canada. Objectives: The objectives of the present study were (1) to identify the flexible and efficient statistical method to derive lung function reference equations that can be used to obtain the predicted values and Lower Limit of Normal (LLN) for lung function in children and adolescents, and (2) to obtain prediction equations for FVC, FEV1 and FEV1=FVC for First Nations children and adolescents living in rural Saskatchewan, Canada. Methods: Spirometric results from a prospective cohort study, "First Nations Lung Health Project" were used to identify 130 healthy non-smoking children and adolescents. The predicted values and LLN of spirometric indices [Forced Vital Capacity (FVC), Forced Expiratory Volume at one second (FEV1) and FEV1 and FVC ratio (FEV1=FVC)] were calculated for school-going children and adolescents ages 6-17 years. The subjects participating in the study were from two Cree First Nations on-reserve communities located in rural Saskatchewan, Canada. All lung function values were reviewed by a respirologist for acceptability of the test. Following an extensive literature review, the Generalized Additive Models for Location, Scale and Shape (GAMLSS) was identified as a flexible statistical tool to model the lung function variables. The lung function indices were assumed to follow a Box-Cox-Cole-Green (BCCG) distribution with median, , coe ffcient of variation and skewness . Akaike Information Criteria (AIC) approach was used to obtain the reference models. The LLN was calculated by taking the fifth percentile of the prediction equations of the lung function variables. The above approach is recommended for the prediction of lung function of multi-ethnic people aged 3-95 years from different ethnic groups by the Global Lung Function Initiative (GLI). Results: Significant differences were observed in lung function (FVC, FEV1 and FEV1=FVC) and anthropometric measurements between both boys and girls. Therefore, fitting separate equations for both sexes are justified. In GLI, polynomial bases of order 6-7 were used for modeling the meadian, coefficient of variation and skewness . In this study, lower order polynomial bases (up to order 4) were enough to obtain the reference models. In GLI, the polynomial bases were divided by 100 to let it lie within 0 to 1. In this study, the polynomials were divided by 20 to lie these between 0 and 1. The predicted values of FVC was higher than the values for FEV1 in both boys and girls. Therefore the values of FEV1=FVC ratios is less than 100% in this population. In girls, the difference between the curves of FVC and FEV1 was smaller compared to boys. Thus, the total volume of air for girls during exhalation are close to the volume of air exhaled at the first second. The estimated curves showed that the models fitted the lung function data reasonably well. Conclusions: The results in this study showed that the optimum model for the prediction of lung function were almost similar to the ones used by GLI for the prediction of lung function of all-age multi-ethnic populations.The predicted values and LLN values of the lung function variables reported in this study can be recommended to health-care providers for the use in diagnosis respiratory diseases in First Nations children and adolescents in rural Saskatchewan. Small sample (n < 150) was a limitation of this study. This study limitation can be overcome by including more individuals from the follow-up study, which will be conducted in 2016.
23

Exposition domestique à des polluants chimiques de l’air intérieur : modélisation et évaluation de l’impact sur la santé respiratoire chez le jeune enfant : Bilan au terme d’une année de suivi de la cohorte de nouveau-nés PARIS / Domestic exposure to indoor air chemical pollutants : modeled exposure related to respiratory health effects in infancy : findings from the PARIS (Pollution and Asthma Risk an Infant Study) birth cohort

Roda, Célina 27 September 2012 (has links)
Problématique : La qualité de l’air intérieur est devenue une préoccupation majeure de santé publique, en raison du temps passé à l’intérieur des locaux et de la diversité des contaminants biologiques et des polluants chimiques présents. Objectifs : Il s’agit de renseigner et de modéliser l’exposition domestique à des polluants chimiques retrouvés dans l’air intérieur et d’en étudier le lien avec la morbidité respiratoire au cours de la première année de vie des nouveau-nés de la cohorte PARIS (Pollution and Asthma Risk : an Infant Study). Méthodes : À 1, 3, 6, 9 et 12 mois, des questionnaires sanitaires sont adressés aux parents pour renseigner la survenue des infections des voies respiratoires et des symptômes évocateurs d’asthme (sifflements, toux sèche nocturne, etc.). Des questionnaires environnementaux sont envoyés en parallèle pour documenter le cadre et le mode de vie des enfants. Pour pallier l’imprécision résultant d’une évaluation de l’exposition aux polluants de l’air intérieur par simple questionnaire, des investigations environnementales complémentaires ont été conduites, à 1, 6, 9 et 12 mois, au domicile d’un échantillon aléatoire de 196 nouveau-nés de la cohorte PARIS et dans des crèches parisiennes fréquentées par ces enfants. Les données issues des mesurages domestiques répétés ont été confrontées aux données recueillies par questionnaires afin d’établir des modèles prédictifs s concentrations domestiques annuelles de polluants. Ces modèles ont ensuite été appliqués à l’ensemble des logements fréquentés par les enfants de la cohorte afin de les classer au regard de leur exposition domestique annuelle pour étudier l’impact sanitaire de cette exposition. Résultats : Les modèles prédictifs des concentrations mesurées ont permis d’identifier les déterminants des niveaux de formaldéhyde, de dioxyde d’azote, de toluène et de tétrachloroéthylène : les sources continues et leur caractère récent (panneaux de particules, parquet vitrifié, stratifié, flottant et peinture), les sources discontinues (combustion et proximité au pressing) et les paramètres d’aération et de ventilation conditionnant l’entrée ou la sortie du polluant selon leur origine dominante. Au cours de la première année de vie, près d’un enfant sur deux présente une infection des voies respiratoires basses, 14,8 % une toux sèche nocturne. Concernant l’impact sanitaire de l’exposition aux polluants chimiques, après ajustement sur l’ensemble des facteurs de risque, seule l’exposition domestique au formaldéhyde majore la survenue des infections et plus particulièrement des infections sifflantes. L’exposition au formaldéhyde est aussi associée à la toux sèche nocturne et plus particulièrement chez les enfants sans antécédents parentaux d’allergie. Conclusion : Une exposition domestique aux polluants chimiques de l’air intérieur, tels que le formaldéhyde, peut être associée à la morbidité respiratoire du jeune enfant. Ces résultats viennent appuyer les mesures prises par les pouvoirs publics concernant les émissions des matériaux / There is a growing public health concern about indoor air quality due to the time spent indoors and the presence of numerous biological and chemical pollutants. Aims: To assess indoor chemical pollutant levels, to model domestic exposure and to examine the impact of indoor chemical pollutants on the respiratory health of infants from the PARIS birth cohort, during their first year of life. Methods: Multiple self-administered questionnaires were used to gather information from parents about respiratory infections and asthma-like symptoms (wheezing, nocturnal dry cough. . . ) in their infants at ages 1, 3, 6, 9 and 12 months. Details about home characteristics and family living conditions were also collected by phone interview when the child was 1 month old, and mailed questionnaires captured changes at 3, 6, 9 and 12 months. Pollutant air sampling (aldehyde, volatile organic compound, nitrogendioxide and nicotine) were conducted at 1, 6, 9 and 12 months in the bedrooms of a subset of randomly selected 196infants. Repeated pollutant measurements were joined with interview and questionnaire information to construct annual pollutant exposure models for all infants. Furthermore, an environmental investigation was performed in Parisian child day care centers to document chemical exposure levels. Results: Formaldehyde, toluene, nitrogen dioxide and perchlororethylene level determinants: continuous sources (particleboard, varnished parquet floor, wall coating), discontinuous sources (combustion, dry cleaning facilities) and aeration parameters were identified. At one year, around half of babies experienced at least one lower respiratory infection, and nearly half of those infections included wheezing, 14,8 % of babies suffered from a nocturnal dry cough. After known risk factors were considered, lower respiratory infections were associated with estimated formaldehyde levels, and formaldehyde exposure is also related to nocturnal dry cough, especially in infants without parental history of allergy. Conclusion: This study shows that formaldehyde exposure in early life is associated with respiratory health in infants, promoting public actions regarding emissions from materials
24

Avaliação da condição respiratória em população rural exposta a agrotóxicos no município de São José de Ubá, Estado do Rio de Janeiro / Assessment of respiratory status in rural population exposed to pesticides in the community of Sao Jose de Uba, State of Rio de Janeiro, Brazil

Buralli, Rafael Junqueira 19 January 2016 (has links)
O uso excessivo de produtos agrotóxicos na agricultura se tornou um problema de saúde pública e representa um risco à saúde humana, especialmente dos trabalhadores rurais e seus familiares. Os agrotóxicos são responsáveis por várias doenças e o sistema respiratório é especialmente sensível a esses contaminantes. Em São José de Ubá (SJU), a economia local é extremamente dependente do plantio de tomates, que demandam uso intensivo de agrotóxicos, principalmente organofosforados, carbamatos e piretróides. O monitoramento da saúde das populações expostas pode ser essencial para reduzir danos e mitigar riscos. Objetivo geral: Avaliar a prevalência de sintomas respiratórios e função pulmonar de trabalhadores rurais e familiares expostos a agrotóxicos no município de SJU. Materiais e Métodos: Estudo transversal com amostragem por conveniência em 48 trabalhadores rurais e 34 familiares. Foi realizada uma caracterização da área e população de estudo, entrevistas orientadas por questionário, levantamento de dados de morbidade e mortalidade, análise de marcadores biológicos, pesquisa de sintomas respiratórios e avaliação da função pulmonar. Resultados: A média de idade e tempo de exposição (em anos) dos trabalhadores rurais aos agrotóxicos foi de 42,9 e 30,2 anos e entre seus familiares foi 45,7 e 18,8 anos. 81,3 por cento dos trabalhadores rurais afirmaram ter contato com agrotóxicos no momento da pesquisa e 77,1 por cento dos produtores e 94,1 por cento dos familiares afirmaram estar expostos domesticamente aos agrotóxicos. Foi encontrada uma alta prevalência de sintomas respiratórios entre trabalhadores rurais (39,1 por cento com crise de tosse, 26,1 por cento com aperto no peito e 23,9 por cento com alergia no nariz e rinite) e entre seus familiares (41,4 por cento com crise de tosse, 41,4 por cento com alergia no nariz e rinite, 24,1 por cento com falta de ar e 20,7 por cento com aperto no peito). As medidas de exposição avaliadas estiveram significativamente associadas com alterações da relação de VEF1/CVF e FEF25-75 por cento encontradas na prova de função pulmonar, embora a relação de VEF1/CVF tenha perdido sua significância quando ajustada para tabagismo. Foi encontrada ainda uma associação significativa entre as medidas de exposição e alterações enzimáticas, mas perderam essa associação quando ajustadas por sexo. Conclusões: A população rural avaliada em SJU está exposta ocupacionalmente e ambientalmente a agrotóxicos e, como consequência, apresentou uma alta prevalência de sintomas respiratórios e algumas alterações na função pulmonar. Estes achados sinalizam para a vulnerabilidade do sistema respiratório a esses contaminantes. Sugere-se um acompanhamento longitudinal dessa população com uma ampliação do tamanho amostral e a adoção de um grupo controle para comparação dos resultados. / Excessive use of pesticides in agriculture has become a public health problem and poses a risk to human health, especially of rural workers and their families. Pesticides are responsible for various diseases and respiratory system is especially sensitive to these contaminants. In Sao Jose de Uba - SJU, the local economy is heavily dependent on the planting of tomatoes, which require intensive use of pesticides, especially organophosphates, carbamates and pyrethroids. Monitoring the health of exposed populations may be essential to reduce damage and mitigate risks. Objective: To evaluate the prevalence of respiratory symptoms and lung function of rural workers and family members exposed to pesticides in SJU. Materials and Methods: Cross-sectional study with convenience sampling composed by 48 rural workers and 34 family members. A characterization of the area and population, interviews guided by questionnaire of exposure data and respiratory symptoms, data collection of morbidity and mortality, analysis of biomarkers and evaluation of lung function was conducted in the period of season (2014). Results: The mean age and exposure time (in years) of farm workers to pesticides was 42.9 and 30.2 years and of their family members was 45.7 and 18.8 years. 81.3 per cent of rural workers said they had contact with pesticides at the time of the survey and 77.1 per cent of farmers and 94.1 per cent of family members said they were domestically exposed to pesticides. A high prevalence of respiratory symptoms was found among farm workers (39.1 per cent with cough crisis, 26.1 per cent with chest tightness and 23.9 per cent with allergy in the nose and rhinitis) and among their family members (41.4 per cent with cough crisis, 41.4 per cent with allergy in the nose and rhinitis, 24.1 per cent with shortness of breath and 20.7 per cent with chest tightness). The assessed exposure measurements were significantly associated with alterations of FEV1/FVC and FEF25-75 per cent found in pulmonary function, although the FEV1/FVC ratio has lost its significance when adjusted for smoking. It was also found a significant association between the exposure measurements and enzymatic changes, but lost this association when adjusted for sex. Conclusions: The rural population assessed in SJU is occupationally and environmentally exposed to pesticides and, as a result, had a high prevalence of respiratory symptoms and some changes in lung function. These findings suggests to the vulnerability of the respiratory system to these contaminants. It is recommended further studies regarding this population with a larger samples and the adoption of a control group for comparison of results.
25

Avaliação da condição respiratória em população rural exposta a agrotóxicos no município de São José de Ubá, Estado do Rio de Janeiro / Assessment of respiratory status in rural population exposed to pesticides in the community of Sao Jose de Uba, State of Rio de Janeiro, Brazil

Rafael Junqueira Buralli 19 January 2016 (has links)
O uso excessivo de produtos agrotóxicos na agricultura se tornou um problema de saúde pública e representa um risco à saúde humana, especialmente dos trabalhadores rurais e seus familiares. Os agrotóxicos são responsáveis por várias doenças e o sistema respiratório é especialmente sensível a esses contaminantes. Em São José de Ubá (SJU), a economia local é extremamente dependente do plantio de tomates, que demandam uso intensivo de agrotóxicos, principalmente organofosforados, carbamatos e piretróides. O monitoramento da saúde das populações expostas pode ser essencial para reduzir danos e mitigar riscos. Objetivo geral: Avaliar a prevalência de sintomas respiratórios e função pulmonar de trabalhadores rurais e familiares expostos a agrotóxicos no município de SJU. Materiais e Métodos: Estudo transversal com amostragem por conveniência em 48 trabalhadores rurais e 34 familiares. Foi realizada uma caracterização da área e população de estudo, entrevistas orientadas por questionário, levantamento de dados de morbidade e mortalidade, análise de marcadores biológicos, pesquisa de sintomas respiratórios e avaliação da função pulmonar. Resultados: A média de idade e tempo de exposição (em anos) dos trabalhadores rurais aos agrotóxicos foi de 42,9 e 30,2 anos e entre seus familiares foi 45,7 e 18,8 anos. 81,3 por cento dos trabalhadores rurais afirmaram ter contato com agrotóxicos no momento da pesquisa e 77,1 por cento dos produtores e 94,1 por cento dos familiares afirmaram estar expostos domesticamente aos agrotóxicos. Foi encontrada uma alta prevalência de sintomas respiratórios entre trabalhadores rurais (39,1 por cento com crise de tosse, 26,1 por cento com aperto no peito e 23,9 por cento com alergia no nariz e rinite) e entre seus familiares (41,4 por cento com crise de tosse, 41,4 por cento com alergia no nariz e rinite, 24,1 por cento com falta de ar e 20,7 por cento com aperto no peito). As medidas de exposição avaliadas estiveram significativamente associadas com alterações da relação de VEF1/CVF e FEF25-75 por cento encontradas na prova de função pulmonar, embora a relação de VEF1/CVF tenha perdido sua significância quando ajustada para tabagismo. Foi encontrada ainda uma associação significativa entre as medidas de exposição e alterações enzimáticas, mas perderam essa associação quando ajustadas por sexo. Conclusões: A população rural avaliada em SJU está exposta ocupacionalmente e ambientalmente a agrotóxicos e, como consequência, apresentou uma alta prevalência de sintomas respiratórios e algumas alterações na função pulmonar. Estes achados sinalizam para a vulnerabilidade do sistema respiratório a esses contaminantes. Sugere-se um acompanhamento longitudinal dessa população com uma ampliação do tamanho amostral e a adoção de um grupo controle para comparação dos resultados. / Excessive use of pesticides in agriculture has become a public health problem and poses a risk to human health, especially of rural workers and their families. Pesticides are responsible for various diseases and respiratory system is especially sensitive to these contaminants. In Sao Jose de Uba - SJU, the local economy is heavily dependent on the planting of tomatoes, which require intensive use of pesticides, especially organophosphates, carbamates and pyrethroids. Monitoring the health of exposed populations may be essential to reduce damage and mitigate risks. Objective: To evaluate the prevalence of respiratory symptoms and lung function of rural workers and family members exposed to pesticides in SJU. Materials and Methods: Cross-sectional study with convenience sampling composed by 48 rural workers and 34 family members. A characterization of the area and population, interviews guided by questionnaire of exposure data and respiratory symptoms, data collection of morbidity and mortality, analysis of biomarkers and evaluation of lung function was conducted in the period of season (2014). Results: The mean age and exposure time (in years) of farm workers to pesticides was 42.9 and 30.2 years and of their family members was 45.7 and 18.8 years. 81.3 per cent of rural workers said they had contact with pesticides at the time of the survey and 77.1 per cent of farmers and 94.1 per cent of family members said they were domestically exposed to pesticides. A high prevalence of respiratory symptoms was found among farm workers (39.1 per cent with cough crisis, 26.1 per cent with chest tightness and 23.9 per cent with allergy in the nose and rhinitis) and among their family members (41.4 per cent with cough crisis, 41.4 per cent with allergy in the nose and rhinitis, 24.1 per cent with shortness of breath and 20.7 per cent with chest tightness). The assessed exposure measurements were significantly associated with alterations of FEV1/FVC and FEF25-75 per cent found in pulmonary function, although the FEV1/FVC ratio has lost its significance when adjusted for smoking. It was also found a significant association between the exposure measurements and enzymatic changes, but lost this association when adjusted for sex. Conclusions: The rural population assessed in SJU is occupationally and environmentally exposed to pesticides and, as a result, had a high prevalence of respiratory symptoms and some changes in lung function. These findings suggests to the vulnerability of the respiratory system to these contaminants. It is recommended further studies regarding this population with a larger samples and the adoption of a control group for comparison of results.
26

Der Einfluss von Haltungsbedingungen auf Parameter der Tiergesundheit unter besonderer Berücksichtigung von Atemwegserkrankungen in fünf Schweinemastbetrieben im Raum Thüringen

Richter, Annerose 16 June 2015 (has links) (PDF)
Hintergrund und Zielstellung: Im Zuge der Intensivierung der Schweinemast kommen Atemwegsinfektionen und deren klinische Auswirkungen auf die Tiere, in Verbindung mit möglichen Wechselwirkungen zu den Umgebungsfaktoren, eine entscheidende Bedeutung für die Tiergesundheit und Wirtschaftlichkeit der Betriebe zu. Daher war es Ziel dieser Arbeit, unter Feldbedingungen festzustellen, inwieweit Korrelationen zwischen Parametern des Stallklimas, dem Nachweis potentiell pathogener Infektionserreger des Respirationstraktes, klinischem Befund der Tiere, dem Lungenbefund am Schlachtband und den Leistungsfaktoren bestehen. Material und Methoden: Über den Zeitraum von einem Jahr wurden fünf Schweinemastbetriebe in Thüringen, mit Betriebsgrößen im Bereich von 2480 bis 22 000 Mastplätzen hinsichtlich Tiergesundheit, insbesondere der Atemwegsgesundheit und Stallklima untersucht. Betriebskenndaten über Stallbau, Belegungsdichte, Lüftungs- und Heiztechnik sowie Fütterungs, -Tränke- und Impfregime wurden aufgenommen. Für die Untersuchungen wurden pro Betrieb zwei Abteile ausgewählt. Dabei lagen die betriebsabhängigen Abteilgrößen zwischen 159 bis 751 Tieren. In diesen Abteilen wurden bei einer Stichprobengröße von zehn Tieren in zwei Mastperioden, Sommer und Winter, zu jeweils drei Zeitpunkten (Vormast, Mittelmast und Endmast) 840 Blutproben entnommen und bezüglich der lungenpathogenen Erreger PRRSV, PCV 2, SIV sowie APP untersucht. PRRSV und PCV 2 betreffend, wurde sowohl auf Virus mittels in house-PCR-Untersuchungen gepoolter Proben, als auch serologisch auf Antikörper mittels ELISA untersucht. Für den Erreger SIV erfolgte eine serologische Untersuchung auf Antikörper mittels HAH sowie für APP mittels ELISA. Des Weiteren kam es in den entsprechenden Abteilen zur Durchführung stallklimatischer Messungen, wobei die Stallklimaparameter Lufttemperatur, Relative Luftfeuchte, Luftgeschwindigkeit sowie die Beleuchtungsstärke mithilfe von Geräten der Firma Testo sowie die Konzentrationen von CO2, O2, NH3und H2S mithilfe eines Multiwarn-Mehrgasmessgeräts der Firma Dräger ermittelt wurden. Gleichzeitig erfolgte eine klinische Befunderhebung in den Gruppen, mit der Bildung eines Klinikscores mit Schwerpunkt Lungengesundheit, sowie die Aufnahme der Leistungsparameter: durchschnittliche tägliche Zunahme, Mortalität der Gruppe und dem Tierbehandlungsindex, aus denen ein Leistungsscore ermittelt wurde. Im Zuge der Schlachtung wurden 9921 Schlachtkörper, insbesondere das Geschlinge und die Lungen, makroskopisch beurteilt und daraus ein modifizierter Organboniturscore, auf Grundlage des Organbefundindex nach Blaha gebildet. Alle Score-Bewertungen erfolgten nach Punkten und gaben somit eine Aussage zum Tiergesundheitsstatus der Betriebe. Höhere Punktzahlen entsprachen einem schlechterem Gesundheits- bzw. Leistungsstatus. Somit konnten Wechselwirkungen zwischen den Ergebnissen der Blutuntersuchungen, den Stallklimaparametern, dem Klinik- und Leistungsscore sowie dem Organboniturscore mittels statistischer Auswertung hergestellt werden, wobei die einzelnen Bestände sowohl betriebsübergreifend als auch auf Bestandsebene untersucht wurden. Aufgrund durchgeführter Umbaumaßnahmen in drei Beständen wurde ein Vergleich alter und neuer Betriebsteile in die Betrachtungen mit einbezogen. Ergebnisse: Keiner der Betriebe wies eine vollständige Erregerfreiheit auf, was für die endemische Verbreitung der Infektionserreger, insbesondere PRRSV, PCV 2 sowie APP spricht. SIV wurde lediglich in einem Bestand nachgewiesen. Serokonversionen hinsichtlich PRRSV gingen signifikant mit vermehrtem Husten der Tiere (p = 0,027) und einer höheren klinischen Gesamtpunktzahl (p = 0,016) einher. Bei Virusnachweis zeigte sich mit p = 0,047 eine signifikant schlechtere Lungengesundheit. Hinsichtlich des Stallklimas bestand für die Parameter Temperatur, Relative Luftfeuchte, CO2 Gehalt sowie den Schadgasgehalten der Stallluft ein starker Bezug zu den unterschiedlichen Mastperioden Sommer und Winter, mit vorrangig schlechteren Werten in der Winterperiode. Diese Klimaparameter lagen oftmals über den Grenz- bzw. Regelwertbereichen, mit Auswirkungen auf die Atemwegsgesundheit. Mit Ausnahme des Parameters NH3 ergaben sich bestandsübergreifend mit p ≤ 0,01 signifikante Zusammenhänge zu den klinischen Befunden (höhere Teilpunkzahlen Lungengesundheit korrelieren mit ρ = 0,250 zum CO2-sowie mit ρ = 0,222 zum H2S-Gehalt der Stallluft, negativ mit ρ = −0,396 zur Temperatur) sowie NH3 inbegriffen (mit einer Korrelation von ρ = 0,401) zu den Pneumoniebefunden. Ebenfalls bestandsübergreifend zeigte sich ein signifikanter Zusammenhang zwischen der Infektion von APP (p = 0,038) sowie PRRSV (p = 0,001) und einer erhöhten Anzahl an Pleuritiden. Des Weiteren zeigten sich mit einer Signifikanz von p ≤ 0,01 in Verbindung mit verstärkten klinischen Symptomen auch signifikant mehr makroskopisch sichtbare Pneumonien bei der Schlachtung (Korrelation der Gesamtpunktzahl Klinik mit ρ = 0,297). Bestandsabhängig wurden beim Vorhandensein multipler Erregerspektren im Betrieb erhöhte Lungenbefunde ermittelt. Beziehungen der Klima- und Klinikparameter sowie der Lungenbefunde zu den Leistungsparametern, konnten nur in geringem Maße festgestellt werden. So wurden beispielsweise keine Korrelationen zwischen den Schadgasparametern und der durchschnittlichen Masttagszunahme festgestellt. Hier scheint der genetische Aspekt einen starken Einfluss zu besitzen. Schlussfolgerungen: Anhand der Untersuchungen konnten sowohl einzelbetrieblich als auch betriebsübergreifend Signifikanzen zwischen den einzelnen Parametern festgestellt werden. Die gegenseitige Beeinflussung und Abhängigkeit aller Faktoren ist jedoch immer herdenabhängig und variiert, je nach Bestandsdynamik.
27

Impact of Biogas Digesters on Health and Quality of Life Measures of Kenyan Farmwomen

Dohoo, Carolyn 05 August 2011 (has links)
Women living in rural Kenya rely on wood for cooking and are exposed to elevated amounts of wood smoke. The objective of this thesis was to assess the health and quality of life benefits of installing biogas digesters on rural Kenyan dairy farms. Thirty-one farms with biogas digesters and 31 farms without digesters (referent group) were assessed for wood utilization practices, basic respiratory and self-reported health, and exposure to volatile organic compounds (VOCs). Women with biogas digesters spent less time and money acquiring wood, and less time exposed to wood smoke (p<0.01). Multivariable linear regression showed associations between daily wood consumption and having a biogas digester, family size, and number of cows. Individual VOCs were lower in cookhouses on biogas farms (p<0.001) and women with biogas digesters reported fewer respiratory symptoms. Biogas digesters are one technology that can reduce reliance on wood fuel and reduce exposures to harmful wood smoke.
28

Exposició a subproductes de cloració a les piscines i efectes respiratoris en banyistes

Font Ribera, Laia 29 November 2010 (has links)
ANTECEDENTS: La natació té beneficis per la salut, però l’assistència a piscines comporta l’exposició a subproductes de la cloració (SPC). Els banyistes podrien tenir cert risc de patir efectes respiratoris, com l’asma, però l’evidència és inconsistent. L’objectiu principal és determinar si l’assistència a piscines s’associa a efectes respiratoris aguts i crònics, especialment l’asma infantil. MÈTODES: Per avaluar efectes aguts es mesura funció pulmonar i diferents biomarcadors respiratoris a 48 adults sans abans i després de nedar en una piscina clorada. Per avaluar efectes crònics: estudi transversal a Sabadell (9-12 anys; N=3.223) i estudi longitudinal en una cohort de naixement (ALSPAC, Regne Unit; 7-10 anys; N=5.738). Informació sobre assistència a piscines durant la infància i símptomes d’asma i al lèrgia recollida amb qüestionari i espirometria. RESULTATS: L’únic efecte agut detectat és un lleuger augment de la permeabilitat pulmonar, estimada amb la concentració de CC16 en sang, correlacionat amb l’exposició a SPC i l’exercici físic. L’assistència a piscines no s’associa a un augment del risc d’asma, tampoc entre els nens atòpics, però s’associa a una menor prevalença d’alguns símptomes respiratoris i millor funció pulmonar. Els nens asmàtics que havien anat a la piscina tenen menys símptomes d’asma. CONCLUSIÓ: Es detecta un lleuger efecte agut sobre la permeabilitat de l’epitel li pulmonar dels banyistes, però actualment se’n desconeix la rellevància clínica. Aquest treball no dóna suport a la hipòtesi que l’assistència a piscines durant la infància augmenta el risc d’asma. Al contrari, la natació s’associa lleugerament a menys símptomes d’asma entre els 7 i 12 anys d’edat. / BACKGROUND: Swimming is a healthy activity, but swimming pool attendance enhances the exposure to disinfection by-products (DBP). Swimming pool attendants may have a higher risk of suffering from respiratory conditions, such as asthma, but the evidence is unconsistent. The aim is determine if swimming pool attendance is associated with acute and chronic respiratory effects, especially childhood asthma. METHODS: To evaluate acute effects lung function and several respiratory biomarkers were measured in 48 healthy adults before and alter swimming in a chlorinated pool. To evaluate chronic effects: crosssectional study in Sabadell (9-12 years; N=3,223) and longitudinal study in a birth cohort (ALSPAC, UK; 7- 10 years; N=5,738). Information on swimming pool attendance and asthma and allergic symptoms was collected by questionnaire and spirometry. RESULTS: The only acute effect detected was an slight increase in the lung epithelium permeability, estimated by serum CC16 concentration, correlated with DBP exposure and physical activity. Swimming pool attendance was not associated to an increased asthma risk, neither in atopic children, but was associated with a lower prevalence of some respiratory symptoms and higher lung function. Asthmatic children who attended swimming pools had less asthma symptoms. CONCLUSION: An slight acute effect on the lung epithelium permeability was detected among swimmers, but the clinical relevance is currently not understood. This work do not support the hypothesis that swimming pool attendance during childhood increases the asthma risk. On the contrary, swimming is associated to slightly lower prevalence of asthma symptoms in children 7 to 12 years old.
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The effects of air pollution particles on clearance mechanisms within the lung

Barlow, Peter George January 2004 (has links)
The effects of inhaled air pollution particles on lung clearance mechanisms is an important factor in understanding how the mammalian lung deals with such pollutants and, as such, how exposure to these pollutants can be regulated. The nanoparticle(diameter S lOOnm) and transition metal components of PMIO (particulate matter with a diameter less than lO~m) have been implicated as playing major roles in the impairment of alveolar macrophage function and the subsequent retention of particles in the respiratory system. The aim of this study was to investigate the effects of components of PMIO on macrophage functions both directly, by examining macrophage phagocytosis and migration, and indirectly, by studying peripheral factors affecting macrophagefunction such as recruitment by type II cells and complement based mechanisms. We hypothesised that the alveolar epithelial type II cell line would release leukocyte chemoattractants in response to particle exposure and that this could be measured by use of a macrophage migration assay. A sub-toxic dose (125 ~g/ml)of surrogate air pollutionparticles (fine and nanoparticle carbon black and titanium dioxide) was established by measuring LOH release from a murine alveolar macrophage cell line (1774.2) and an alveolar epithelial type II cell line (L-2) in response to particle exposure. Optimisation ofa chemotaxis assay and measurement of macrophage migration towards conditioned medium obtained from the particle-exposed type II cells was conducted and it was determined that carbon black nanoparticles induced type II cells to secrete a chemoattractant that resulted in significant increases in macrophage migration compared to the negative control. This was in contrast to other particle types tested in this study which did not induce any increases in macrophage migration. It was also hypothesised that complement proteins could be involved in macrophage recruitment to sites of particle deposition and, as such, the migration of macrophages towards particle exposed blood serum was examined in vitro. Foetal bovine serum (FBS) was exposed to fine and nanoparticle caroon black and titanium dioxide (l-Smg/ml) for 2 hours. It was found, in accord with the previous study involving type II cells, that carbon black nanoparticles could activate the generation of chemotactic factors in serum that could subsequently induce significant increases (p < 0.001) in macrophage migration when serum was diluted to 10% using serum-free RPMI 1640 culture medium. This effect could be ameliorated by co-incubating the particle-treated serum in the presence of the antioxidant Trolox suggesting that oxidative stress played a role in the generation of the chemoattractant molecules. However, incubation of the serum with a pure oxidant at a range of doses did not result in the generation of chemotactic molecules suggesting that another factor could be involved in the chemoattractant generation. Further investigation to determine the exact molecular mechanism behind the chemoattractant generation is warranted. In contrast to the previous studies, we have also found evidence that components of PM₁₀ can cause decreased efficacy of macrophage clearance mechanisms in vivo and in vitro. It was hypothesised that PM₁₀ instillation would result in a decrease in macrophage phagocytic potential and an increase in chemotactic potential ex vivo. Rats were instilled with 125 and 250μg of PM₁₀ collected from North Kensington, London or sterile saline (negative control). Post-instillation (18 hours), significantly elevated concentrations of TNFa were detected in the BAL fluid together with a significant increase in the number of BAL neutrophils. Phagocytosis and chemotaxis assays conducted with BAL macrophages ex vivo showed that macrophage migration towards a positive chemoattractant, Zymosan Activated Serum (ZAS), was significantly lower than the macrophages obtained from the negative control rats. Macrophage phagocytosis of latex beads ex vivo was also found to be significantly decreased when PM₁₀ was visible inside the cell. An in vitro study where a macrophage cell line (J774.Al) was exposed to a low dose of nanoparticle carbon black (31.25μg) together with varying concentrations (100μM - 100nM) of zinc chloride (ZnCl₂) was also conducted. Exposure of macrophages to nanoparticle carbon black and zinc chloride alone induced a decrease in macrophage phagocytosis. It was found that when macrophages were co-exposed to nanoparticle carbon black and ZnCl₂, there was an additive decrease in macrophage phagocytic potential. The results contained within this manuscript demonstrate that the components of PM₁₀ can induce adverse effects on specific aspects of macrophage clearance mechanisms, but that nanoparticles can also stimulate the production of chemoattractants to aid in the recruitment of phagocytes and subsequent particle clearance. Although a contrary relationship appears to exist between these findings, the recruitment of leukocytes in response to particulate exposure is a mechanism that supports particle clearance. However, the retardation of phagocytic and chemotactic mechanisms in particle exposed macrophages may help to explain the increased toxicity, inflammation and retention time observed with nanoparticle inhalation.
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Characterizing the Indoor Air Environment In the Homes of First Nation Children and Youth Using Remote Community-Based Research Methods: Household Conditions, Air Quality, and Preliminary Health Outcomes

Ng Cheng Hin, Rhiannon 18 January 2023 (has links)
Indoor air quality is a critical determinant of physical and mental health. Despite evidence linking poor indoor air quality to adverse health outcomes, this issue is understudied in the context of First Nations children and youth health and wellbeing. The objectives of this study were to (1) characterize indoor air quality, housing conditions, and respiratory health of children living in the Kanesatake First Nation and (2) evaluate the feasibility of using remote community-based participatory methods in the context of First Nations health research. Community-assisted data collection occurred between June 2021 and February 2022 in the Kanesatake First Nation, Quebec. Indoor air data were collected from 31 randomly selected houses. Results showed elevated levels of contaminants, including particulate matter, benzene, toluene, and xylene, compared to the Canadian averages. Houses generally lacked adequate ventilation, and over one-quarter were reported to be in need of major repairs. We developed instruction tools for air sampling and house inspection to facilitate off-site data collection. High rates of participant completion (95%) and low attrition rates (5%) indicated the feasibility of remote community-based participatory research methods. Lessons learnt are summarized and important recommendations are made for adaptation to improve future data collection. This research served as a pilot project for a multi-year, cross-Nation study, as well as the first study to evaluate the indoor air environment in the Kanesatake First Nation.

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