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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.
321

Regulation of Cytokines and Chemokines during Lung Infection with Nontypeable Haemophilus influenzae

Clarke, Jodie Louise, n/a January 2008 (has links)
An animal model of respiratory infection was used to determine the effect of various factors, thought to influence the ability of the host to clear bacteria, on the host?s innate response to an NTHi lung infection. Mucosal immunisation with NTHi has previously been shown to enhance the clearance of NTHi from the lung in an animal model of infection through the increased recruitment of phagocytes. Comparisons of cytokine and chemokine kinetic profiles were made in order to determine differences between innate and acquired immune response and the way in which mucosal immunisation controls the innate immune response to NTHi. Increased production of proinflammatory cytokines and chemokines in the early stages of NTHi lung infection enhanced the ability to clear bacteria from the rat lung in the immune animals through the increased recruitment of phagocytes to the site. Mucosal immunisation was found to alter the cytokine and chemokine mRNA profiles of CD4+ and CD8+ cells, with increased levels of MCP-1 protein being detected in both types of immune cells. An antecedent viral infection has been shown to increase the chance of developing a respiratory bacterial infection. The NTHi model of respiratory infection was used to characterise the effect that a viral infection had on the host response to the host?s innate response to a bacterial infection and the ability to clear the bacteria. The host?s ability to clear NTHi from the rat lung was enhanced by an antecedent viral infection through alterations to the innate immune response and the cytokine and chemokine kinetic profiles. The use of a mutant strain of NTHi deficient in a component of Lipooligosaccharide (LOS), Phosphorylcholine (ChoP), was utilised as a tool to characterise the innate immune response to LOS. Animals challenged with the LOS mutant strain had a reduced inflammatory response to NTHi through the decreased production of pro-inflammatory cytokines and chemokines and the reduced recruitment of phagocytes to the site of infection. This thesis has contributed valuable information to enable a better understanding of the host?s innate immune response to respiratory infection. This study has identified the role of cytokines and chemokines in the innate response to a respiratory bacterial infection and the enhanced ability of the host to clear NTHi from the lung.
322

Investigations into the role of zinc in normal and allergic respiratory epithelial cells and tissues / [Ai Quynth Truong-Tran]

Truong-Tran Ai Quynh January 2002 (has links)
Includes bibliographical references (leaves 234-280) / xxviii, 292, [72] leaves : ill. (some col.), plates (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Medicine, 2002
323

Essays on the Economics of Public Health

Ward, Courtney 05 December 2012 (has links)
This dissertation considers the economics of public health in the context of respiratory disease, a leading cause of morbidity and mortality. The pervasive nature of respiratory illness represents a significant reduction to health and longevity, but private actions to prevent illness may not consider the full-scale benefit of societal health improvement. In this thesis, I consider two determinants of respiratory illness: (1) the spread of influenza disease and (2) air pollution. In both cases, public policy aims to attenuate the effects of these factors by incentivizing or mandating preventative action. Because such interventions come at a cost, it is important to consider the magnitude of benefits associated with these actions. I consider each determinant in turn. First, I provide causal evidence on the health and economic consequences of an ongoing broad-scope vaccination program. The Ontario Influenza Immunization Campaign expanded the scope of vaccine coverage leading to a 20-percent increase in vaccination. Using the timing of this campaign and exogenous variation in vaccine quality, I link higher vaccination rates to decreases in lost-work-time, hospitalization, and death. Results indicate that, when vaccine quality is high, the program leads to higher gains for Ontario relative to other provinces and in short, an ounce of prevention is worth a pound of cure. Second, I provide evidence of the impact of air pollution on respiratory health. Recent changes in standards for air pollution are highly contentious and represent stringent constraints on economic activity. Evidence from this dissertation directly informs this debate. By linking daily pollution to hospital admissions for municipalities across Ontario, I study the impact of air pollution at levels below those historically considered. Results indicate that particulate matter has a significant effect on respiratory health of children but that ozone and carbon monoxide have little effect on respiratory hospitalizations for all age groups.
324

The Development and Assessment of a Lung Biopsy Technique for Early BRD Detection

Burgess, Brandy Ann 06 August 2009
The objectives of this project were: 1) to determine if live animal lung biopsy could be used to characterize early pathologic changes in the bovine lung associated with bovine respiratory disease (BRD), 2) determine if specific infectious respiratory pathogens can be identified in association with early pathological changes, and 3) determine whether pulmonary pathology characterized by live animal lung biopsy at arrival and at the time of initial BRD diagnosis was associated with health and production outcomes of feedlot steers in a commercial feedlot.<p> A live animal percutaneous lung biopsy technique was developed to obtain a lung sample from the right middle lung lobe in intercostal space (ICS) 4 using a Bard® Magnum® reusable biopsy instrument and a modified 4-mm (8g) biopsy needle. The lung biopsy procedure was limited to 2 attempts per biopsy time. In the technique development, 34 animals chronically affected with BRD were utilized, 20 animals in the preliminary development followed by 14 additional animals in a commercial feedlot setting. The technique resulted in 1 fatality of 34 steers (2.9%) and lung parenchyma was harvested in 19 of 34 steers (55.9%) chronically affected with BRD. In addition, in the commercial feedlot setting this procedure was determined to take about 20 minutes per animal.<p> The final study was performed on one hundred feedlot steers considered at high risk of developing BRD from twenty pens within a commercial feedlot. Study animals were enrolled in three different groups: sick on arrival (ARR-SA) consisting of 27 study animals and 13 matched control animals; pen pulls with no fever (PP-NF) consisting of 14 study animals and matched 7 controls; and pen pulls with an undifferentiated fever (PP-UF) consisting of 26 study animals and 13 matched controls. Live animal percutaneous lung biopsies were collected from the right middle lung lobe at 3 different times within the first 30 days of the feeding period, about 2 weeks apart. All samples were histopathologically evaluated and were assessed for the presence of <i>Mycoplasma bovis</i>, <i>Mannheimia haemolytica</i>, Histophilus somni and bovine viral diarrhea virus with immunohistochemistry.<p> A total of 295 lung biopsies were performed yielding 210 (71.2%) lung samples that were sufficient for histopathological evaluation. A histopathology score was awarded to each biopsy based on certain histopathological lesions being present. Only 20 lung biopsy samples from 19 animals received a histopathology score (ie, pulmonary lesions were present) with the most common score being a 1 (maximum score is 20). There were too few lung biopsy samples with a histopathology score to reveal any association with subsequent health events.<p> Immunohistochemistry (IHC) was performed on all lung biopsies recovered yielding one lung sample to be positive for both <i>Mannheimia haemolytica</i> and <i>Mycoplasma bovis</i> from the PP-UF group. There were too few positive samples to reveal any association between IHC and histopathology score.<p> A post mortem evaluation was performed by a study veterinarian on all study animals who died or were humanely euthanized due to poor treatment response. In this study only 4 steers died or were euthanized due to poor treatment response and 3 control steers were humanely euthanized. There were too few animals to reveal any association between histopathology score and post mortem diagnosis.<p> On entry into the feedlot, weights between ARR-SA and the PP-UF and PP-NF groups were significantly different (p<0.05). This is likely an effect of the different processing groups of cattle. At study allocation, the body weights of ARR-SA and PP-UF, PP-UF and their matched controls, and PP-NF and their matched controls were also significantly different (p<0.05). This is likely due to the PP-UF and PP-NF groups experiencing illness for a longer period of time resulting in greater weight loss than the ARR-SA animals as well as the control animals, who were not clinically sick.<p> The live lung biopsy procedure utilized in this study did not appear to cause any long lasting adverse effects as the BRD case fatality rates from the study animals were comparable to the overall case fatality rates reported by the feedlot for fall placed calves. In fact, the study animals experienced a decreased fatality rate compared to the feedlots overall fatality rate. This may be due to the study animals inadvertently being monitored more closely as the pen checkers were aware of and participating in the study. On post mortem evaluation there was no evidence of adhesions at the biopsy site. This procedure was performed on 134 feedlot steers resulting in only 2 acute deaths as a direct result of the live animal percutaneous lung biopsy procedure.<p> The results of this study indicate that live animal, percutaneous lung biopsy can be performed safely on feedlot steers in a commercial feedlot with few clinical side effects. In this study there were only 2 fatalities in 134 steers (1.5%) due to the biopsy procedure or 2 fatalities per 349 sampling times (0.6%) This technique did not prove useful either as a diagnostic tool for the determination of early lung pathology in BRD or as prognostic indicator for health and production outcomes. However, this lung biopsy technique may be a useful diagnostic tool for chronic pneumonia assessment.
325

Essays on the Economics of Public Health

Ward, Courtney 05 December 2012 (has links)
This dissertation considers the economics of public health in the context of respiratory disease, a leading cause of morbidity and mortality. The pervasive nature of respiratory illness represents a significant reduction to health and longevity, but private actions to prevent illness may not consider the full-scale benefit of societal health improvement. In this thesis, I consider two determinants of respiratory illness: (1) the spread of influenza disease and (2) air pollution. In both cases, public policy aims to attenuate the effects of these factors by incentivizing or mandating preventative action. Because such interventions come at a cost, it is important to consider the magnitude of benefits associated with these actions. I consider each determinant in turn. First, I provide causal evidence on the health and economic consequences of an ongoing broad-scope vaccination program. The Ontario Influenza Immunization Campaign expanded the scope of vaccine coverage leading to a 20-percent increase in vaccination. Using the timing of this campaign and exogenous variation in vaccine quality, I link higher vaccination rates to decreases in lost-work-time, hospitalization, and death. Results indicate that, when vaccine quality is high, the program leads to higher gains for Ontario relative to other provinces and in short, an ounce of prevention is worth a pound of cure. Second, I provide evidence of the impact of air pollution on respiratory health. Recent changes in standards for air pollution are highly contentious and represent stringent constraints on economic activity. Evidence from this dissertation directly informs this debate. By linking daily pollution to hospital admissions for municipalities across Ontario, I study the impact of air pollution at levels below those historically considered. Results indicate that particulate matter has a significant effect on respiratory health of children but that ozone and carbon monoxide have little effect on respiratory hospitalizations for all age groups.
326

The Development and Assessment of a Lung Biopsy Technique for Early BRD Detection

Burgess, Brandy Ann 06 August 2009 (has links)
The objectives of this project were: 1) to determine if live animal lung biopsy could be used to characterize early pathologic changes in the bovine lung associated with bovine respiratory disease (BRD), 2) determine if specific infectious respiratory pathogens can be identified in association with early pathological changes, and 3) determine whether pulmonary pathology characterized by live animal lung biopsy at arrival and at the time of initial BRD diagnosis was associated with health and production outcomes of feedlot steers in a commercial feedlot.<p> A live animal percutaneous lung biopsy technique was developed to obtain a lung sample from the right middle lung lobe in intercostal space (ICS) 4 using a Bard® Magnum® reusable biopsy instrument and a modified 4-mm (8g) biopsy needle. The lung biopsy procedure was limited to 2 attempts per biopsy time. In the technique development, 34 animals chronically affected with BRD were utilized, 20 animals in the preliminary development followed by 14 additional animals in a commercial feedlot setting. The technique resulted in 1 fatality of 34 steers (2.9%) and lung parenchyma was harvested in 19 of 34 steers (55.9%) chronically affected with BRD. In addition, in the commercial feedlot setting this procedure was determined to take about 20 minutes per animal.<p> The final study was performed on one hundred feedlot steers considered at high risk of developing BRD from twenty pens within a commercial feedlot. Study animals were enrolled in three different groups: sick on arrival (ARR-SA) consisting of 27 study animals and 13 matched control animals; pen pulls with no fever (PP-NF) consisting of 14 study animals and matched 7 controls; and pen pulls with an undifferentiated fever (PP-UF) consisting of 26 study animals and 13 matched controls. Live animal percutaneous lung biopsies were collected from the right middle lung lobe at 3 different times within the first 30 days of the feeding period, about 2 weeks apart. All samples were histopathologically evaluated and were assessed for the presence of <i>Mycoplasma bovis</i>, <i>Mannheimia haemolytica</i>, Histophilus somni and bovine viral diarrhea virus with immunohistochemistry.<p> A total of 295 lung biopsies were performed yielding 210 (71.2%) lung samples that were sufficient for histopathological evaluation. A histopathology score was awarded to each biopsy based on certain histopathological lesions being present. Only 20 lung biopsy samples from 19 animals received a histopathology score (ie, pulmonary lesions were present) with the most common score being a 1 (maximum score is 20). There were too few lung biopsy samples with a histopathology score to reveal any association with subsequent health events.<p> Immunohistochemistry (IHC) was performed on all lung biopsies recovered yielding one lung sample to be positive for both <i>Mannheimia haemolytica</i> and <i>Mycoplasma bovis</i> from the PP-UF group. There were too few positive samples to reveal any association between IHC and histopathology score.<p> A post mortem evaluation was performed by a study veterinarian on all study animals who died or were humanely euthanized due to poor treatment response. In this study only 4 steers died or were euthanized due to poor treatment response and 3 control steers were humanely euthanized. There were too few animals to reveal any association between histopathology score and post mortem diagnosis.<p> On entry into the feedlot, weights between ARR-SA and the PP-UF and PP-NF groups were significantly different (p<0.05). This is likely an effect of the different processing groups of cattle. At study allocation, the body weights of ARR-SA and PP-UF, PP-UF and their matched controls, and PP-NF and their matched controls were also significantly different (p<0.05). This is likely due to the PP-UF and PP-NF groups experiencing illness for a longer period of time resulting in greater weight loss than the ARR-SA animals as well as the control animals, who were not clinically sick.<p> The live lung biopsy procedure utilized in this study did not appear to cause any long lasting adverse effects as the BRD case fatality rates from the study animals were comparable to the overall case fatality rates reported by the feedlot for fall placed calves. In fact, the study animals experienced a decreased fatality rate compared to the feedlots overall fatality rate. This may be due to the study animals inadvertently being monitored more closely as the pen checkers were aware of and participating in the study. On post mortem evaluation there was no evidence of adhesions at the biopsy site. This procedure was performed on 134 feedlot steers resulting in only 2 acute deaths as a direct result of the live animal percutaneous lung biopsy procedure.<p> The results of this study indicate that live animal, percutaneous lung biopsy can be performed safely on feedlot steers in a commercial feedlot with few clinical side effects. In this study there were only 2 fatalities in 134 steers (1.5%) due to the biopsy procedure or 2 fatalities per 349 sampling times (0.6%) This technique did not prove useful either as a diagnostic tool for the determination of early lung pathology in BRD or as prognostic indicator for health and production outcomes. However, this lung biopsy technique may be a useful diagnostic tool for chronic pneumonia assessment.
327

A Digital Oximetry Based Method for Estimating Respiratory Disturbance Index

Chang, Shu-hao 15 July 2005 (has links)
SAS has become an increasingly important public-health problem in recent years. It can abversely affect neurocognitive, cardiovascular, respiratory diseases and can also cause behavior disorder. Moreover, up to 90¢H of these cases are obstructive sleep apnea (OSA). Therefore, it is important that how to diagnose, detect and treat OSA. The respiratory disturbance index is one parameter of estimating OSA. Polysomnography can monitor the OSA with relatively fewer invasive techniques. However, polysomnography-based sleep studies are expensive and time-consuming because they require overnight evaluation in sleep laboratories with dedicated systems and attending personnel. Based on the digital oximetry, this work introduces the estimating respiratory disturbance index. In particular, via signal processing, feature parameters and artificial intelligence, this thesis describes an off-line SpO2-based RDI estimating system.
328

Detection and analysis of Anti-SARS-CoV Immunoglobulin G and associated risk factor among healthcare workers in Taiwan

Huang, Shiau-Jiuan 12 July 2006 (has links)
Severe acute respiratory syndrome (SARS) is an emerging infectious disease that first manifested in humans in China in November 2002 and has subsequently spread worldwide. According to the World Health Organization, 8098 cases occurred during the outbreak, and healthcare workers accounted for 1707 (21%) of the cases. To determine the prevalence of SARS infection of healthcare workers in Taiwan, we performed a serosurvey by the recombinant protein-based enzyme-linked immunosorbent assay (ELISA) to test for immunoglobulin (Ig) G antibodies to the SARS coronavirus (SARS-CoV) among 1525 healthcare workers in 26 hospitals that admitted SARS patients in mid-May, 2003. Then, a case-control study was carried out to evaluate the risk factors of SARS infection among the healthcare workers. A total of 52 infected staffs and 78 hospital and age matched non-infected controls were recruited. The seroprevalence rate was 3.68% (58/1525) for healthcare workers. Univariate analysis showed that with the habit of drinking coffee or tea, taking care of fever patients more than 8 days, ever practice of CPR, suction of sputum, taking patient¡¦s temperature, use of P100 mask, use of N95 mask, use of face cover, use of goggles, use of gown, removing gloves after work, working in isolation area or fever screen station were significantly protective factors. In addition, eating jujube was a risk factor for SARS infection. Then, the multivariate analysis showed that use of P100 ¡]OR: 0.056, 95%CI: 0.019-0.162, p value: <0.001¡^and working in isolation area ¡]OR: 0.153, 95%CI: 0.029-0.810, p value: 0.027¡^or fever screen station¡]OR: 0.103, 95%CI: 0.011-0.963, p value: 0.046¡^were the most important protective factors for SARS infection. These findings suggest that nosocomial infection of SARS can be prevented effectively by use of P100 and the triage screening in emergency departments.
329

Measuring efficiency of ventilator-dependent integrated respiratory care in Taiwan : An Application of Data Envelopment Analysis

Chi, Chao-Chuan 15 July 2008 (has links)
According to the report of the Bureau of National Healthcare Insurance (NHI) in 1997, the total expenses on ventilator-dependent patients was about 7,100 million yuan in hospital, account for 3% of the cost of one year of health insurance of the whole people. To efficiently control their admission so as to decrease unsuitable utilization of mechanical ventilation, and to achieve the rational growth of medical expenditure, the NHI has developed the perspective payment system for the ventilator-dependent integrated delivery system (IDS) respiratory care program since July 1, 2000. Ventilator-dependent patients, difficult to wean, rely on the mechanical ventilation, using for at least 21 days in succession. The patients are dependent upon long-term mechanical respiratory care. Integrating the different level of respiratory care, IDS program is including ¡§ICU , intensive care unit¡¨, ¡¨RCC, respiratory care center¡¨, ¡¨ RCW , respiratory care ward¡¨ and ¡§home care¡¨ and pay in accordance with the level. The purpose of IDS program is to promote the quality of respiratory care and effectively to utilize the limited medical resources. The data for this research was retrieved from the 2002-2004 ¡§NHI database¡¨ that includes charge and discharge information for 115 hospitals. Of the 115 hospitals analyzed using data envelopment analysis (DEA) technique, to explore the whole efficiency and purely technological efficiency.
330

Adjuvant effect of phthalates and monophthalates in a murine injection model /

Thor Larsen, Søren. January 2002 (has links)
Ph.d.

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