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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.
71

Practicas estratégicas preventivas frente al Covid-19 en la familia Meza Pucuhuayla en el periodo de agosto a octubre del 2020 en el distrito de El Agustino

Meza Pucuhuayla, Adamary Iriana 04 December 2020 (has links)
Introducción: El distrito de El Agustino pertenece a la DIRIS Lima Este con una población de 197,788 pobladores y un índice de pobreza de 22,10%. El principal problema de salud es el alto índice de morbilidad por IRAS y las neoplasias como la primera causa de mortalidad. Asimismo, el ascenso de casos de Covid-19 en el primer trimestre del año. Descripción del proyecto: Se planteó como objetivo mejorar la practica de estratégias preventivas frente al Covid-19 en la familia Meza Pucuhuayla. El total de participantes fueron 3 integrantes, un grupo heterogéneo en edades. Se elaboraron materiales educativos para todas las sesiones educativas y talleres, listas de cotejo para los monitoreos semanales. Se empleó la plataforma Kahoot para los pre y post test de las sesiones educativas. Resultados: Para las actividades planteadas se logró el 100% de eficacia y cobertura en las sesiones educativas con los temas de alimentación saludable, enfermedades respiratorias y generalidades del Covid-19. En relación a talleres todos tuvierton un volumen de 3 participantes instruidos y con una productividad en promedio de 10 minutos por cada integrante. Para la actividad de monitoreo de actividad fisica se logró un volumen de 6 listas de cotejo y una cobertura del 200%. Para el taller de bioseguridad y desinfección frente al Covid-19 se logró un volumen de 12 listas de cotejo monitoreadas. Conclusiones: Se logró incrementar prácticas de hábitos saludables para lo que se comparó en tres momentos las actividades físicas y elaboración de alimentación saludable. Asimismo, se logró identificar medidas preventivas para las enfermedades respiratorias prevalentes en sesiones educativas; se implementó un protocolo de desinfección y bioseguridad en el hogar en el cual se aprendió el correcto uso de desifecctantes, técnica de lavado de manos e inocuidad de alimentos. / Introduction: The district of El Agustino belongs to the East Lima DIRIS with a population of 197,788 inhabitants and a poorness rate of 22.10%. The main health problem is the high rate of morbidity due to ARIS and neoplasms as the first cause of mortality. Likewise, the rise in Covid-19 cases in the first quarter of the year. Description of project: The objective was to improve the practice of preventive strategies against Covid-19 in the Meza Pucuhuayla family. The total of participants were 3 members, a heterogeneous age group. Educational materials were prepared for all educational sessions and workshops, checklists for weekly monitoring. The Kahoot platform was used for the pre and post tests of the educational sessions. Results: For the proposed activities, 100% efficiency and coverage were achieved in the educational sessions with the topics of healthy eating, respiratory diseases and generalities of the Covid-19. In relation to workshops, all had a volume of 3 instructed participants and with an average productivity of 10 minutes for each member. For the physical activity monitoring activity, a volume of 6 checklists was achieved and a coverage of 200%. For the biosafety and disinfection workshop against Covid - 19, a volume of 12 monitored checklists was achieved. Conclusions: It was possible to increase the practices of healthy habits, for which physical activities and the preparation of healthy eating were compared in three moments. Likewise, it was possible to identify preventive measures for prevalent respiratory diseases in educational sessions; a disinfection and biosecurity protocol was implemented in the home in which the correct use of disinfectants, hand washing technique and food safety were learned. / Trabajo de investigación
72

Regulation and Function of Neuronal Nicotinic Acetylcholine Receptors in Lung Cancer: A Dissertation

Improgo, Ma. Reina D. 10 August 2011 (has links)
Lung cancer is the leading cause of cancer-related mortality worldwide. The main risk factor associated with lung cancer is cigarette smoking. Research through the years suggests that nicotine in cigarettes promotes lung cancer by activating signaling pathways that lead to cell proliferation, cell survival, angiogenesis, and metastasis. Nicotine’s cellular actions are mediated by its cognate receptors, nicotinic acetylcholine receptors (nAChRs). Here, I describe the expression levels of all known human nAChR subunit genes in both normal and lung cancer cells. Of note, the genes encoding the α5, α3, and β4 subunits (CHRNA5/A3/B4) are over-expressed in small cell lung carcinoma (SCLC), the most aggressive form of lung cancer. This over-expression is regulated by ASCL1, a transcription factor important in normal lung development and lung carcinogenesis. The CHRNA5/A3/B4 locus has recently been the focus of a series of genetic studies showing that polymorphisms in this region confer risk for both nicotine dependence and lung cancer. I show that CHRNA5/A3/B4 depletion results in decreased SCLC cell viability. Furthermore, while nicotine promotes SCLC cell viability and tumor growth, blockade of α3β4 nAChRs inhibits SCLC cell viability. These results suggest that increased expression and function of nAChRs, specifically the α3β4α5 subtype, potentiate the effects of nicotine in SCLC. This dual hit from the carcinogens in tobacco and the cancer-promoting effects of nicotine, may provide a possible mechanism for the increased aggressiveness of SCLC. In addition, nAChRs can be activated by the endogenous ligand, acetylcholine, which acts as an autocrine/paracrine growth factor in SCLC. Increased function of α3β4α5 nAChRs in SCLC could also potentiate acetylcholine’s mitogenic effects. This mechanism, combined with other known autocrine/paracrine growth loops in SCLC, may help explain the ineffectiveness of available therapies against SCLC. In an effort to add to the current arsenal against SCLC, I screened a 1280-compund library using a bioluminescence-based viability assay I developed for high-throughput applications. Primary screening, followed by secondary and tertiary verification, indicate that pharmacologically active compounds targeting neuroendocrine markers inhibit SCLC cell viability.
73

Impact of COPD on the Mortality and Treatment of Patients Hospitalized with Acute Decompensated Heart Failure (The Worcester Heart Failure Study): A Masters Thesis

Fisher, Kimberly A. 30 July 2014 (has links)
Objective: Chronic obstructive pulmonary disease (COPD) is a common comorbidity in patients with heart failure, yet little is known about the impact of this condition in patients with acute decompensated heart failure (ADHF), especially from a more generalizable, community-based perspective. The primary objective of this study was to describe the in-hospital and post discharge mortality and treatment of patients hospitalized with ADHF according to COPD status. Methods: The study population consisted of patients hospitalized with ADHF at all 11 medical centers in central Massachusetts during 4 study years: 1995, 2000, 2002, and 2004. Results: Of the 9,748 patients hospitalized with ADHF during the years under study, 35.9% had a history of COPD. The average age of this population was 76.1 years, 43.9% were men, and 93.3% were white. At the time of hospital discharge, patients with COPD were less likely to have received evidence-based heart failure medications, including beta-blockers and ACE inhibitors/angiotensin receptor blockers, than patients without COPD. Multivariable adjusted in-hospital death rates were similar for patients with and without COPD. However, among patients who survived to hospital discharge, patients with COPD had a significantly higher risk of dying at 1 (adjusted RR 1.10; 95% CI 1.06, 1.14) and 5-years (adjusted RR 1.40; 95% CI 1.28, 1.42) after hospital discharge than patients who were not previously diagnosed with COPD. Conclusions: COPD is a common co-morbidity in patients hospitalized with ADHF and is associated with a worse long-term prognosis. Further research is required to understand the complex interactions of these diseases and to ensure that patients with ADHF and COPD receive optimal treatment modalities.
74

Eosinophils as Drivers of the IL-23/IL-17 Axis: Implications for Acute Aspergillosis and Allergic Asthma: A Dissertation

Guerra, Evelyn V. Santos 23 February 2016 (has links)
Aspergillus fumigatus is an opportunistic fungal pathogen that causes lethal invasive pulmonary disease in immunocompromised hosts and allergic asthma in sensitized individuals. This dissertation explores how eosinophils may protect hosts from acute infection while driving asthma pathogenesis by co-producing IL-23 and IL-17 in both contexts. In an acute model of pulmonary aspergillosis, eosinophils were observed to associate with and kill A. fumigatus spores in vivo. In addition, eosinopenia was correlated with higher mortality rates, decreased recruitment of inflammatory monocytes to the lungs, and decreased expansion of lung macrophages. As IL-17 signaling must occur on a local level to elicit its stereotypical response, such as the up-regulation of antimicrobial peptides and specific chemokines from stromal cells, eosinophils were discovered to be a significant source of pulmonary IL-17 as well as one of its upstream inducers, IL-23. In the context of asthma, this discovery opens a new paradigm whereby eosinophils might be driving asthma pathogenesis.
75

Symptom Experience and Treatment Delay during Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Dissertation

Chin, Elizabeth D. 21 August 2012 (has links)
Chronic obstructive pulmonary disease (COPD) is a major health problem in the United States. Acute exacerbations of COPD are primarily responsible for the physical, psychological and economic burden of this disease. Early identification and treatment of exacerbations is important to improve patient and healthcare outcomes. Little is known about how patients with COPD recognize an impending exacerbation and subsequently decide to seek treatment. The purpose of this qualitative descriptive study was to explore and describe symptom recognition and treatment delay in individuals experiencing an acute exacerbation of chronic obstructive pulmonary disease (COPD). Leventhal’s Common Sense Model of illness representation undergirded this study. Using semi-structured interviews, adults hospitalized with an acute exacerbation of COPD were asked to describe their symptom experience and self care behaviors, including treatment seeking, in the days to weeks prior to hospitalization. Data analysis revealed one main theme: Recognizing, responding and reacting to change, and six subthemes: Something’s coming, Here we go again, Seeking urgent treatment, Riding it out, Not in charge anymore and My last day that richly described the COPD exacerbation experience. The study revealed that patients experience an illness prodrome prior to exacerbation and have a recurrent exacerbation symptom pattern that was self-recognized. Treatment seeking was most influenced by the speed and acuity of exacerbation onset, severity of breathlessness, fears of death, nature of patient-provider relationship and the perception of stigmatization during prior healthcare encounters. These findings are important for the development of interventions to improve patient recognition and management of COPD exacerbations in the future.
76

Pseudomonas aeruginosa Major Pseudopilin XcpT is Incorporated into The Type IV Pilus Under Native Conditions

Rana, Navpreet K. 10 1900 (has links)
<p>Retractable surface appendages Type IV pili (T4P) are one of the major virulence determinants in the opportunistic pathogen <em>Pseudomonas aeruginosa </em>(Pa), that is the leading cause of mortality in CF patients. T4P are heteropolymers composed of the major-pilin subunit PilA and the less-abundant minor pilins (MPs), FimU/PilV/W/X/E. Pilins share high sequence and structural similarity with pseudopilins (XcpT/U/V/W/X), that are proposed to form a periplasmic-structure in the evolutionarily related Type II secretion system (T2SS). Similar to T4P system, the T2SS is a multi-subunit complex that spans the inner (IM) and the outer (OM) membranes. It involves a two-step process facilitating the secretion of toxins into the extracellular milieu from the periplasm.</p> <p>Using immunogold TEM analysis and Western blot we identified, under native conditions, the major pseudopilin of T2SS XcpT, is incorporated into the T4P appendage, thus appearing on the surface. This is in contrast to previous studies reporting, the otherwise periplasmic structure, the pseudopilus appears on the surface only upon over-expression of XcpT. Further, we identified this incorporation is strictly dependent on PilA expression, such that levels of surface-XcpT co-varied with the levels of surface-PilA. However, XcpT incorporation into the T4P fiber did not affect T4P-mediated twitching motility or T2SS-mediated elastase secretion. Based on these observations we proposed two explanations. Firstly, given the similarity between XcpT and type IV pilins, it is possible the pseudopilin is recognized by the T4P machinery and therefore is incorporated into the pilus. Secondly, since XcpT incorporation does not affect T4P-mediated motility, it may affect other properties of T4P, such adherence during biofilm formation, previously associated with surface-exposed pseudopilus. In addition, we also identified enhanced expression of <em>fimU</em> and <em>pilX</em> MPs drastically increased elastase secretion, through a yet to be discovered mechanism. Regardless, our results present an alternative role of both minor pilins and XcpT in their non-native systems suggesting there is more overlap between the T4P and T2S systems than previously appreciated. Further exploration of this overlap will aid in the study of the two systems in Pa, as well as in other pathogens.</p> / Master of Science (MSc)
77

ASPECTS OF AIRWAY STRETCH-ACTIVATED CONTRACTIONS ASSESSED IN PERFUSED INTACT BOVINE BRONCHIAL SEGMENTS

Hernandez, Jeremy M. January 2011 (has links)
<p>Asthma is a disease characterized by transient airway smooth muscle contraction leading to episodes of reversible airway narrowing. It affects over 300 million people worldwide and is implicated in over 250 000 deaths annually. The primary clinical features of asthma include airway inflammation, hyperresponsiveness, and remodeling. Generally, asthmatic patients experience exacerbations between periods of diminished symptoms. Interestingly, in addition to these above mentioned hallmarks, asthmatics have also been shown to react differently to ventilatory mechanical strain. This is most evident when assessing the effect of a deep inspiration (DI), clinically measured as a breath taken from functional residual capacity to total lung capacity, in healthy individuals <em>versus</em> asthmatics. These deep inspiratory efforts have been shown to produce a bronchodilatory response in healthy individuals, whereas in asthmatics, DIs are less effective in producing bronchodilation, can cause more rapid airway re-narrowing, and even bronchoconstriction in moderate to severe asthmatics. The mechanism by which a DI is able to cause bronchoconstriction remains ambiguous. Previous theories suggest that this phenomenon is intrinsic to airway smooth muscle (ASM) itself. However, the airway inflammation present in asthmatic airways may also add to the increased ASM contractility following stretch, by the release of mediators that can prime the contractile apparatus to react excessively in the presence of stretch.</p> <p>Thus, collectively, the studies contained in this thesis are linked to the general theme of greater characterization of the signalling mechanisms that regulate airway stretch-activated contractions using a pharmacological approach in intact bovine bronchial segments, with the hope of providing novel insights into the mechanisms that regulate the DI-induced bronchoconstriction seen in asthmatics.</p> / Doctor of Philosophy (Medical Science)
78

Effect of Inhaled Corticosteroid on CT-derived Lung Density in an in vivo Allergic Inflammation Model

Lindsay, Kristi L. 10 1900 (has links)
<p>Allergic asthma is a disease involving airway inflammation, commonly linked to allergen exposure. Computed tomography (CT) is used to quantitatively assess changes in density, hence inflammation, in the lung. CT imaging provides the ability to non-invasively and longitudinally study disease progression and evaluate treatment efficacy. The objective of this study was to determine the sensitivity of CT to detect the anti-inflammatory effects of budesonide (BUD) by measuring airway tissue density in a rat model of allergic airway disease.</p> <p>Female<strong> </strong>Brown Norway rats were exposed intratracheally to house dust mite (HDM) extract (250 µg in 100µL saline) or saline control every other day for a total of five administrations (inflammatory phase). ABUD dose and temporal response study was performed usingBUD 0, 10, 100, and 300 µg/kg administered concurrently with HDM for three and six treatments (treatment phase). CT scanning was performed at baseline, post inflammatory phase, and after three and six BUD treatments. From the CT, density was measured in a defined volume of interest surrounding the major airways. Bronchoalveolar lavage (BAL) and histological samples were collected at the same time points.</p> <p>After the inflammatory phase, a significant increase in peribronchial density was found in the HDM group compared to controls. This corresponded to a significant increase in inflammation by histology andBALtotal cell count (TCC), specifically eosinophils. Within the treatment phase after three treatments,BUD100 and 300 µg/kg led to a significant shift in lung density compared to HDM exposure alone, to a state similar to baseline. All BUD treated groups expressed a significant reduction in peribronchial density after six treatments. However, histology andBALTCC only showed a significant decrease in inflammation after six treatments for all three BUD doses.</p> <p>CT densitometry is a sensitive, non-invasive method of evaluating the anti-inflammatory effects of budesonide and can be used for future screening of therapies in allergic lung models. Airway segmentation of CT permits the localized assessment of peribronchial inflammation, while other outcome measurements, such as BAL cytology, provide whole lung assessment which may not accurately reflect important regional changes.</p> / Master of Science (MSc)
79

The Biology of Dendritic Cell Subsets in Allergen-Induced Asthma

Dua, Benny 04 1900 (has links)
<h4> </h4> / <p>Asthma is an inflammatory disorder of the airways, and there has been growing insight into the cellular and molecular mechanisms underlying the inflammatory basis of this disease. Research into the inflammatory mechanisms of asthma has progressively shifted focus from downstream effectors, such as mast cells and eosinophils, up to Th2 lymphocytes and their proallergic cytokines. Even more upstream in the allergic cascade are dendritic cells (DCs), potent APCs that orchestrate immune responses. Evidence supporting a role of DCs in regulating airway allergic inflammation is derived mainly from animal studies. In animal models of asthma, myeloid DCs (mDCs) induce and maintain airway inflammation, while plasmacytoid DCs (pDCs) mediate tolerance and lung homeostasis. It remains uncertain, however, whether this concept of pro-allergic mDCs and anti-allergic pDCs translates from animal to human models. The overall objective of this thesis was to investigate the biology of DC subsets in allergen-induced asthma in asthmatic subjects. Initially, we demonstrate that both mDCs and pDCs increase in the airways of subjects with mild asthma after allergen inhalation. Next, we describe a distinct subpopulation of mDCs, called mDC2s, and demonstrate their association with allergy and asthma severity. Expanding on these findings, we show that mDC2s increase in the airways of mild asthmatics after allergen challenge. Lastly, we explore the potential of pharmacological therapies, anti-OX40L MAb and anti-TSLP MAb, to affect DCs in subjects with mild asthma, and demonstrate no effect of either drug on circulating DC subsets. The studies presented here provide evidence for multiple DC subtypes being involved in the regulation of allergen-induced inflammatory responses, and support continued investigations into the biology of different DC subsets in allergen-induced asthma.</p> / Doctor of Philosophy (Medical Science)
80

Long-term exposure to air pollution and school children's respiratory health and lung function growth: a 1-year prospective cohort study in Guangzhou, China. / 長期暴露空氣污染與中國廣州學齡兒童呼吸系統健康及肺功能發育關係的前瞻性隊列研究 / CUHK electronic theses & dissertations collection / Chang qi bao lu kong qi wu ran yu Zhongguo Guangzhou xue ling er tong hu xi xi tong jian kang ji fei gong neng fa yu guan xi de qian zhan xing dui lie yan jiu

January 2009 (has links)
He, Qiqiang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 142-154). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

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