• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 9
  • 8
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 28
  • 28
  • 21
  • 8
  • 8
  • 6
  • 6
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 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

Biomarkers of oxidative stress and inflammation in biological samples collected from recurrent airway obstruction (RAO)-affected horses and their controls

Tan, Rachel Hsing Hsing 10 June 2008 (has links)
Multiple biomarkers of oxidative stress have been measured and used in human medicine to diagnose and monitor airway disease. The purpose of the study was to determine if similar relationships existed between inflammatory and oxidative stress biomarkers in exhaled breath condensate (EBC), bronchoalveolar lavage fluid (BALF), red blood cells, white blood cells, and plasma; and cytokine expression in airway inflammatory cells and mucosal biopsies of RAO-affected horses and their controls. Sixteen horses in pairs were used: 8 non-RAO-affected (controls) and 8 RAO-affected horses. Samples from all horses were collected at remission (S1), during environmental challenge (S2) and at recovery (S3). RAO-affected horses had significant alterations in cellular glutathione peroxidase (cGPx) activity, ascorbic acid and pH in a number of biological samples. Concentrations of 8-isoprostanes, isofurans, amino acids and mRNA expression of interleukin 4 (IL4), gamma interferon (INFγ), inducible nitric oxide synthase (iNOS), extracellular glutathione peroxidase (GPx-3), and cytosolic superoxide dismutase (SOD-1) were not significantly different or were at the limits of detection. Conductivity was measured and assessed as a potential correctional factor for respiratory fluid dilution. The alterations in biomarker concentrations demonstrate that oxidative stress is an important component of airway inflammation in RAO-affected horses. Further research is warranted in the use of biomarkers and the effects of dietary interventions. / Master of Science
22

Correlação entre condensado do exalado pulmonar, teste de caminhada de seis minutos e shuttle walk test em indivíduos cardiopatas / Correlation between exhaled breath condensate, six minutes walk test and shuttle walk test in heart disease

Nascimento, Marina Neves do 16 May 2014 (has links)
Introdução: As doenças cardíacas ou do aparelho circulatório são as principais causas de morte na população brasileira, sendo responsável por um terço dos óbitos. Embora o tratamento conservador seja amplamente adotado, grande parte das doenças cardiovasculares necessita e tem como tratamento a cirurgia cardíaca, da qual as mais comuns são a cirurgia de revascularização do miocárdio (CRVM) e de troca valvar. Atualmente existem diversos estudos avaliando a função pulmonar ou a capacidade funcional para o acompanhamento do tratamento conservador ou em situação pré-operatória, porém estudos avaliando e correlacionando essas variáveis no pré-cirúrgico são escassos na literatura científica não sendo possível averiguar a existência da relação entre os níveis de nitrito e nitrato e o desempenho nos testes de capacidade funcional. Objetivo: Avaliar a correlação nitrito/nitrato (NOx) do condensado do exalado pulmonar (CEP) e a distância caminhada nos testes de caminhada de 6 minutos (TC6) e shuttle walk test (SWT), além de verificar se a utilização de medicações contendo betabloqueadores, nitrato ou enzima conversora de angiotensina (IECA) podem influenciar nas concentrações de nitrito/nitrato no CEP e nas distâncias caminhadas no TC6 e no SWT e comparar seu comportamento entre valvopatas e coronariopatas no pré operatório de cirurgia cardíaca. Metodologia: Foram selecionados 73 pacientes, dos quais 28 eram coronariopatas e 45 valvopatas, de ambos os sexos, com idade entre 20 e 80 anos, feita coleta do CEP para análise do NOx e submetidos ao TC6 e ao SWT para avaliação da distância caminhada. Resultados: Na análise das concentrações de NOx do CEP não foi encontrada diferença estatisticamente significativa entre as medicações utilizadas via oral contendo nitrato (dinitrato de isossorbida), IECA (captopril ou enalapril) e/ou betabloqueador ou entre os pacientes do grupo coronariopata e grupo valvopata (p>0,05). Houve diferença estatisticamente significativa no TC6 nos valores de frequência cardíaca (FC) inicial, final e repouso e no valor referente à dispnéia final, e no SWT nos valores de FC inicial, final e repouso, na pressão arterial sistólica (PAS) inicial e no valor referente à dispnéia final entre os grupos coronariopata e valvopata. No entanto, foram interrompidos 4 TC6 e 7 SWT do grupo coronariopata devido ao desencadeamento de dor precordial, fato não ocorrido no grupo valvopata, apresentando nível de significância. A FC inicial e de repouso no TC6 e a FC final no SWT dos pacientes que não ingeriram nenhum medicamento antes do teste é diferente em relação à dos pacientes que fizeram uso de quaisquer medicamentos descritos antes do teste sugerindo a ação de medicamentos que modulam a FC como os betabloqueadores. Foi constatado correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial e final de coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC final e de dispnéia final nos valvopatas no TC6, além da correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial de indivíduos coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC inicial nos valvopatas no SWT. Foi identificado correlação negativa moderada na distância caminhada no TC6 e no SWT apenas nos indivíduos coronariopatas. Conclusões: Não foram identificadas influências do uso de medicações betabloqueadoras, nitrato ou IECA sobre a dosagem de NOx ou a distância caminhada em nenhum dos testes e em nenhum dos grupos, no entanto coronariopatas com níveis mais elevados de NOx apresentaram uma distância deambulada menor. / Introduction: Heart disease or circulatory system diseases are the leading causes of death in our population, accounting for one third of deaths. Although conservative treatment is widely adopted, part of cardiovascular disease treatment demands heart surgery, of which the most common are coronary artery bypass grafting (CABG) and valve replacement. Currently there are many studies evaluating lung function or functional capacity for monitoring of conservative treatment or preoperative situation, but studies assessing and correlating these variables in pre surgical are rare in the literature is not possible to ascertain the existence of the relationship between levels of nitrite and nitrate (NOx) in exhaled breath condensate (EBC) and performance in functional ability tests. Methods: were selected 73 patients, 28 with coronary artery diseas and 45 with heart valve disease of both genders, aged 20 to 80 years old. The EBC was collected for analysis of NOx and performed the six minutes walking test (6MWT) and shuttle walk test (SWT) to evaluate the distance walked. Results: the analysis of the concentrations of NOx in EBC has no statistically significant difference found between the medications used, such as oral nitrate (isosorbide dinitrate), ace inhibitors (captopril or enalapril) and/or beta-blockers in both coronary artery disease and heart valve disease (p> 0.05). There was a statistically significant difference in 6MWT for HR initial, final and rest and final dyspnea, and in SWT for HR initial, final and rest, the initial SBP and the final dyspnea between the coronary artery disease e heart valve disease. However, were interrupted 4 6MWT and 7 SWT from coronary artery disease related to chest pain, this fact was not related in patients with valve disease, presenting a significance level. The initial and resting HR during the 6MWT and in SWT final HRr patients not ingesting any medication before the test is different from patients who used any medications before the test, suggesting the action of drugs that modulate the HR, such as beta blockers. Moderate positive correlation was found between the NOx in EBC and SBP initial and final in coronary disease and weak to moderate correlation between the NOx in EBC and final HR and final dyspnea in 6MWT from heart valve disease. Besides the positive moderate correlation between NOx in the EBC and the SBP initial in coronary disease during 6MWT and weak to moderate negative correlation between NOx in the EBC and the HR initial in valve disease during SWT. Moderate negative correlation was identified in the distance walked during the 6MWT and SWT only between individuals with coronary artery disease. Conclusions: the use of beta-blocker drugs, ace inhibitors or nitrate evidenciates no influence on the NOx or on the distance walked in any tests, and none of the groups, however, individuals with coronary artery disease showed higher NOx levels and performed lower distance walked.
23

Correlação entre condensado do exalado pulmonar, teste de caminhada de seis minutos e shuttle walk test em indivíduos cardiopatas / Correlation between exhaled breath condensate, six minutes walk test and shuttle walk test in heart disease

Marina Neves do Nascimento 16 May 2014 (has links)
Introdução: As doenças cardíacas ou do aparelho circulatório são as principais causas de morte na população brasileira, sendo responsável por um terço dos óbitos. Embora o tratamento conservador seja amplamente adotado, grande parte das doenças cardiovasculares necessita e tem como tratamento a cirurgia cardíaca, da qual as mais comuns são a cirurgia de revascularização do miocárdio (CRVM) e de troca valvar. Atualmente existem diversos estudos avaliando a função pulmonar ou a capacidade funcional para o acompanhamento do tratamento conservador ou em situação pré-operatória, porém estudos avaliando e correlacionando essas variáveis no pré-cirúrgico são escassos na literatura científica não sendo possível averiguar a existência da relação entre os níveis de nitrito e nitrato e o desempenho nos testes de capacidade funcional. Objetivo: Avaliar a correlação nitrito/nitrato (NOx) do condensado do exalado pulmonar (CEP) e a distância caminhada nos testes de caminhada de 6 minutos (TC6) e shuttle walk test (SWT), além de verificar se a utilização de medicações contendo betabloqueadores, nitrato ou enzima conversora de angiotensina (IECA) podem influenciar nas concentrações de nitrito/nitrato no CEP e nas distâncias caminhadas no TC6 e no SWT e comparar seu comportamento entre valvopatas e coronariopatas no pré operatório de cirurgia cardíaca. Metodologia: Foram selecionados 73 pacientes, dos quais 28 eram coronariopatas e 45 valvopatas, de ambos os sexos, com idade entre 20 e 80 anos, feita coleta do CEP para análise do NOx e submetidos ao TC6 e ao SWT para avaliação da distância caminhada. Resultados: Na análise das concentrações de NOx do CEP não foi encontrada diferença estatisticamente significativa entre as medicações utilizadas via oral contendo nitrato (dinitrato de isossorbida), IECA (captopril ou enalapril) e/ou betabloqueador ou entre os pacientes do grupo coronariopata e grupo valvopata (p>0,05). Houve diferença estatisticamente significativa no TC6 nos valores de frequência cardíaca (FC) inicial, final e repouso e no valor referente à dispnéia final, e no SWT nos valores de FC inicial, final e repouso, na pressão arterial sistólica (PAS) inicial e no valor referente à dispnéia final entre os grupos coronariopata e valvopata. No entanto, foram interrompidos 4 TC6 e 7 SWT do grupo coronariopata devido ao desencadeamento de dor precordial, fato não ocorrido no grupo valvopata, apresentando nível de significância. A FC inicial e de repouso no TC6 e a FC final no SWT dos pacientes que não ingeriram nenhum medicamento antes do teste é diferente em relação à dos pacientes que fizeram uso de quaisquer medicamentos descritos antes do teste sugerindo a ação de medicamentos que modulam a FC como os betabloqueadores. Foi constatado correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial e final de coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC final e de dispnéia final nos valvopatas no TC6, além da correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial de indivíduos coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC inicial nos valvopatas no SWT. Foi identificado correlação negativa moderada na distância caminhada no TC6 e no SWT apenas nos indivíduos coronariopatas. Conclusões: Não foram identificadas influências do uso de medicações betabloqueadoras, nitrato ou IECA sobre a dosagem de NOx ou a distância caminhada em nenhum dos testes e em nenhum dos grupos, no entanto coronariopatas com níveis mais elevados de NOx apresentaram uma distância deambulada menor. / Introduction: Heart disease or circulatory system diseases are the leading causes of death in our population, accounting for one third of deaths. Although conservative treatment is widely adopted, part of cardiovascular disease treatment demands heart surgery, of which the most common are coronary artery bypass grafting (CABG) and valve replacement. Currently there are many studies evaluating lung function or functional capacity for monitoring of conservative treatment or preoperative situation, but studies assessing and correlating these variables in pre surgical are rare in the literature is not possible to ascertain the existence of the relationship between levels of nitrite and nitrate (NOx) in exhaled breath condensate (EBC) and performance in functional ability tests. Methods: were selected 73 patients, 28 with coronary artery diseas and 45 with heart valve disease of both genders, aged 20 to 80 years old. The EBC was collected for analysis of NOx and performed the six minutes walking test (6MWT) and shuttle walk test (SWT) to evaluate the distance walked. Results: the analysis of the concentrations of NOx in EBC has no statistically significant difference found between the medications used, such as oral nitrate (isosorbide dinitrate), ace inhibitors (captopril or enalapril) and/or beta-blockers in both coronary artery disease and heart valve disease (p> 0.05). There was a statistically significant difference in 6MWT for HR initial, final and rest and final dyspnea, and in SWT for HR initial, final and rest, the initial SBP and the final dyspnea between the coronary artery disease e heart valve disease. However, were interrupted 4 6MWT and 7 SWT from coronary artery disease related to chest pain, this fact was not related in patients with valve disease, presenting a significance level. The initial and resting HR during the 6MWT and in SWT final HRr patients not ingesting any medication before the test is different from patients who used any medications before the test, suggesting the action of drugs that modulate the HR, such as beta blockers. Moderate positive correlation was found between the NOx in EBC and SBP initial and final in coronary disease and weak to moderate correlation between the NOx in EBC and final HR and final dyspnea in 6MWT from heart valve disease. Besides the positive moderate correlation between NOx in the EBC and the SBP initial in coronary disease during 6MWT and weak to moderate negative correlation between NOx in the EBC and the HR initial in valve disease during SWT. Moderate negative correlation was identified in the distance walked during the 6MWT and SWT only between individuals with coronary artery disease. Conclusions: the use of beta-blocker drugs, ace inhibitors or nitrate evidenciates no influence on the NOx or on the distance walked in any tests, and none of the groups, however, individuals with coronary artery disease showed higher NOx levels and performed lower distance walked.
24

Untersuchung von Promotormethylierungen des p16-Gens im Atemkondensat von Patienten mit Bronchialkarzinom und Vergleich mit Tumorpräparaten

Grabner, Enrico 04 December 2014 (has links)
Angesichts der nach wie vor hohen Mortalität und Morbidität des Bronchialkarzinoms ist die Entwicklung geeigneter Methoden zur früheren Diagnostik eine wichtige Notwendigkeit, um die geringe durchschnittliche 5-Jahres-Überlebensrate von 15% – 18% zu steigern. Unter diesem Gesichtspunkt wurde in der vorliegenden Arbeit das Atemkondensat von Patienten mit Bronchialkarzinom als nicht-invasiv und kostengünstig zu gewinnendes Medium auf das Vorliegen eines potentiellen Screeningmarkers – dem methylierten Tumorsuppressor-Gen p16 – untersucht. Dazu wurde ein Versuchsablauf entwickelt, bei dem trotz des geringen DNA-Gehaltes im Atemkondensat p16-Methylierungen nachgewiesen werden konnten. Die letztendlich etablierte Methode war eine methylierungsspezifische nested-PCR mit anschließendem Restriktionsverdau durch das Restriktionsenzym BstUI. Des Weiteren erfolgte die Untersuchung von in Paraffin eingebetteten Tumorpräparaten der Patienten. In der anschließenden statistischen Auswertung wurde der Einfluss von verschiedenen Faktoren wie COPD-Grad, Tumorlage, Tumorart, Nikotinabusus und stattgehabte Chemo- oder Strahlentherapie auf den Methylierungsstatus des p16-Gens analysiert.
25

Capteur de gaz SnO2 fonctionnalisé fonctionnant à température ambiante, sensible et sélectif pour la détection d’ammoniac / Sensitive and selective ammonia gas sensor based on molecularly functionalized tin dioxide working at room temperature

Hijazi, Mohamad 20 October 2017 (has links)
Dans le domaine de la santé, l’analyse de l'haleine expirée offre un outil simple et non invasif pour le diagnostic précoce des maladies. Les capteurs de gaz à base de SnO2 modifies semblent être des dispositifs prometteurs pour détecter les gaz polaires tels que l'ammoniac. Dans cette étude, la fonctionnalisation de la surface de SnO2 a été réalisée afin d'obtenir un capteur de gaz sensible et sélectif à l'ammoniac, qui fonctionne à température ambiante. La première étape de la fonctionnalisation est la fixation covalente d’un film de 3-aminopropyltrethoxysalane (APTES) sur SnO2 en phase vapeur ou liquide. Les caractérisations effectuées par Spectroscopie Infrarouge et Spectrométrie photoélectronique X montrent qu’une quantité plus importante d'APTES a été greffée en phase liquide hydratée. La deuxième étape consiste à fonctionnaliser le SnO2-APTES avec des molécules contenant du chlorure d'acyle avec différents groupes tel que des groupes alkyle, acide et ester. Les capteurs modifiés par des acides et des esters sont sensibles à l’ammoniac entre 0,2 et 10 ppm à température ambiante. Cependant, le SnO2 APTES modifié par l’ester s'est révélé être plus sélectif que le capteur modifié par l'acide pour l’ethanol et le mondxyde de carbone. Ces résultats impliquent que la réponse est générée par les groupes fonctionnels acide et ester, NH3 modifie le moment dipolaire de la couche moléculaire greffée, ce qui entraine une modification de la conductance de SnO2. Le fonctionnement à température ambiante est l'un des avantages de ces capteurs, tout comme leur sélectivité à l'ammoniac en regard d'autres gaz tels que l'éthanol, le monoxyde de carbone et l'acétone. / One of the major challenges in the modern era is how we can detect the disease when we are still feeling healthy via noninvasive methods. Exhaled breath analysis is offering a simple and noninvasive tool for early diagnosis of diseases. Molecularly modified SnO2 sensors seem to be promising devices for sensing polar gases such as ammonia. SnO2 surface functionalization was performed in order to obtain sensitive and selective ammonia gas sensor that operates at room temperature. The first step of functionalization is the covalently attachment of 3-aminopropyltriethoxysilane (APTES) film on SnO2 in vapor or liquid phases. The characterization performed by the Infrared Spectroscopy and X-ray Photoelectron Spectroscopy, show that more APTES were grafted by hydrous liquid phase silanization. The second step was the functionalization of APTES modified SnO2 with molecules having acyl chloride of end functional groups molecules such as alkyl, acid and ester groups. Pure SnO2 and APTES modified SnO2 sensors did not show any significant sensitivity to ammonia (0.2-100 ppm) at 25 °C. On the contrary, acid and ester modified sensors are sensitive to ammonia between 0.2 and 10 ppm at room temperature. However, ester modified SnO2 was more selective than acid modified sensor regarding the ethanol and carbon monoxide gases. Ammonia variates the attached molecular layer’s dipole moment which leads to change in SnO2 conductance. Working at ambient temperature is also one of the advantages of these sensors in addition to the selectivity to ammonia regarding other gases such as ethanol, carbon monoxide and acetone.
26

Influência da poluição do ar na inflamação das vias aéreas e na atividade de doença de pacientes com lúpus eritematoso sistêmico juvenil / Influence of air pollution on airway inflammation and disease activity in childhood-systemic lupus erythematosus

Alves, Andressa Guariento Ferreira 28 August 2018 (has links)
Lúpus eritematoso sistêmico juvenil é uma doença inflamatória autoimune multifatorial com elevação de citocinas inflamatórias e com gravidade variável. Estudos observaram associação entre exposição a poluição do ar e aumento do número de internações hospitalares devido à exacerbação das doenças reumáticas pediátricas e aumento no risco de crianças portadoras de lúpus eritematoso sistêmico juvenil apresentarem atividade de doença moderada /grave após exposição a material particulado e dióxido de nitrogênio. Exposição à poluição do ar pode acarretar agravo agudo em doenças reumatológicas pediátricas, incluindo lúpus eritematoso sistêmico juvenil. Objetivos: Avaliar o efeito da exposição real a poluentes atmosféricos sobre biomarcadores inflamatórios em condensado do ar exalado e sobre a fração de monóxido de nitrogênio em ar exalado em pacientes com lúpus eritematoso sistêmico juvenil. Avaliar ainda, a correlação entre os biomarcadores inflamatórios no ar exalado e atividade da doença. Métodos: Estudo longitudinal de painel de medidas repetidas realizado em 108 visitas consecutivas de pacientes com diagnóstico de lúpus eritematoso sistêmico juvenil sem doenças respiratórias. Por 4 semanas consecutivas, medidas diárias individuais de dióxido de nitrogênio, material particulado fino, temperatura ambiental e humidade relativa do ar foram obtidos. Este ciclo foi repetido a cada 2,5 meses ao longo de um ano, além disso, citocinas do condensado do ar exalado (interleucinas 6, 8, 17 e fator de necrose tumoral-alfa), fração exalada de monóxido de nitrogênio e parâmetros de atividade de doença foram coletados semanalmente. Modelos específicos de equação estimada generalizada foram usadas para avaliar o impacto destes poluentes no risco de Systemic Lupus Erythematosus Disease Activity Index 2000 >= 8, citocinas no condensado do ar exalado e fração exalada de monóxido de nitrogênio, considerando o efeito fixo para medidas repetidas. Os modelos foram ajustados para provas de fase aguda, índice de massa corpórea, infecções, medicações e variáveis meteorológicas. Resultados: Efeito positivo nas medidas de desfechos foi observado para um aumento do intervalo interquartil do material particulado fino (18.12 ?g/m3). Um aumento do intervalo interquartil na média móvel de 7 dias no material particulado fino (lag0 to lag6) foi associado a um aumento de 0.1pg/ml (95%IC:0.01;0.19) e 0.9pg/ml (95%IC:0.05;0,12) nos níveis de interleucina 17 e fator de necrose tumoral-? do condensado do ar exalado, respectivamente. Também foi observado um aumento no risco de Systemic Lupus Erythematosus Disease Activity Index 2000 >= 8 de 1.47(95%CI:1.10;1.84) associado ao aumento da média móvel de material particulado fino. Em adição, um efeito a curto prazo na fração exalada de monóxido de nitrogênio foi evidenciado, medida móvel de 3 dias do material particulado fino foi associada com um aumento de 0.75ppb (95%IC:0.38;1.29) na fração exalada de monóxido de nitrogênio. Conclusão: Exposição a partículas finas inaláveis pode aumentar a inflamação das vias aéreas e posterior inflamação sistêmica nos pacientes com lúpus eritematoso sistêmico juvenil / Systemic lupus erythematosus is an inflammatory multisystem, autoimmune disease with elevated inflammatory interleukins levels. Exposure to air pollution may trigger pulmonary inflammation/systemic inflammation. Objective: The objective of this study was to investigate the association between daily individual exposure to air pollutants and airway inflammation and disease activity in childhood-onset systemic lupus erythematosus patients. A longitudinal panel study was carried out in 108 consecutive appointments with childhood-onset systemic lupus erythematosus patients without respiratory diseases. Methods: Over four consecutive weeks, daily individual measures of nitrogen dioxide, fine particulate matter, ambient temperature, and humidity were obtained. This cycle was repeated every 2.5 months along 1 year, and cytokines of exhaled breath condensate (interleukins 6, 8, 17 and tumoral necrose factor-alpha), fractional exhaled nitrogen monoxide, and disease activity parameters were collected weekly. Specific generalized estimation equation models were used to assess the impact of these pollutants on the risk of Systemic Lupus Erythematous Disease Activity Index 2000 >= 8, exhaled breath condensate cytokines, and fractional exhaled nitrogen monoxide, considering the fixed effects for repetitive measurements. The models were adjusted for inflammatory indicators, body mass index, infections, medication, and weather variables. Results: An interquartile range increase in fine particulate matter 4-day moving average (18.12ug/m3) was associated with an increase of 0.05 pg/ml (95% CI 0.01; 0.09, p = 0.03) and 0.04 pg/ml (95% CI 0.02; 0.06, p = 0.01) in interleukin 17 and tumoral necrosis factor-alpha exhaled breath condensate levels, respectively. Additionally, a short-term effect on fractional exhaled nitrogen monoxide was observed: the fine particulate matter 3-day moving average was associated with a 0.75 ppb increase (95% CI 0.38; 1.29, p = 0.03) in fractional exhaled nitrogen monoxide. Also, an increase of 1.47 (95% CI 1.10; 1.84) in the risk of Systemic Lupus Erythematous Disease Activity Index 2000 >= 8 was associated with fine particulate matter 7-day moving average. Conclusion: Exposure to inhalable fine particles increases airway inflammation/pulmonary and then systemic inflammation in childhood-onset systemic lupus erythematosus patients
27

Influência da poluição do ar na inflamação das vias aéreas e na atividade de doença de pacientes com lúpus eritematoso sistêmico juvenil / Influence of air pollution on airway inflammation and disease activity in childhood-systemic lupus erythematosus

Andressa Guariento Ferreira Alves 28 August 2018 (has links)
Lúpus eritematoso sistêmico juvenil é uma doença inflamatória autoimune multifatorial com elevação de citocinas inflamatórias e com gravidade variável. Estudos observaram associação entre exposição a poluição do ar e aumento do número de internações hospitalares devido à exacerbação das doenças reumáticas pediátricas e aumento no risco de crianças portadoras de lúpus eritematoso sistêmico juvenil apresentarem atividade de doença moderada /grave após exposição a material particulado e dióxido de nitrogênio. Exposição à poluição do ar pode acarretar agravo agudo em doenças reumatológicas pediátricas, incluindo lúpus eritematoso sistêmico juvenil. Objetivos: Avaliar o efeito da exposição real a poluentes atmosféricos sobre biomarcadores inflamatórios em condensado do ar exalado e sobre a fração de monóxido de nitrogênio em ar exalado em pacientes com lúpus eritematoso sistêmico juvenil. Avaliar ainda, a correlação entre os biomarcadores inflamatórios no ar exalado e atividade da doença. Métodos: Estudo longitudinal de painel de medidas repetidas realizado em 108 visitas consecutivas de pacientes com diagnóstico de lúpus eritematoso sistêmico juvenil sem doenças respiratórias. Por 4 semanas consecutivas, medidas diárias individuais de dióxido de nitrogênio, material particulado fino, temperatura ambiental e humidade relativa do ar foram obtidos. Este ciclo foi repetido a cada 2,5 meses ao longo de um ano, além disso, citocinas do condensado do ar exalado (interleucinas 6, 8, 17 e fator de necrose tumoral-alfa), fração exalada de monóxido de nitrogênio e parâmetros de atividade de doença foram coletados semanalmente. Modelos específicos de equação estimada generalizada foram usadas para avaliar o impacto destes poluentes no risco de Systemic Lupus Erythematosus Disease Activity Index 2000 >= 8, citocinas no condensado do ar exalado e fração exalada de monóxido de nitrogênio, considerando o efeito fixo para medidas repetidas. Os modelos foram ajustados para provas de fase aguda, índice de massa corpórea, infecções, medicações e variáveis meteorológicas. Resultados: Efeito positivo nas medidas de desfechos foi observado para um aumento do intervalo interquartil do material particulado fino (18.12 ?g/m3). Um aumento do intervalo interquartil na média móvel de 7 dias no material particulado fino (lag0 to lag6) foi associado a um aumento de 0.1pg/ml (95%IC:0.01;0.19) e 0.9pg/ml (95%IC:0.05;0,12) nos níveis de interleucina 17 e fator de necrose tumoral-? do condensado do ar exalado, respectivamente. Também foi observado um aumento no risco de Systemic Lupus Erythematosus Disease Activity Index 2000 >= 8 de 1.47(95%CI:1.10;1.84) associado ao aumento da média móvel de material particulado fino. Em adição, um efeito a curto prazo na fração exalada de monóxido de nitrogênio foi evidenciado, medida móvel de 3 dias do material particulado fino foi associada com um aumento de 0.75ppb (95%IC:0.38;1.29) na fração exalada de monóxido de nitrogênio. Conclusão: Exposição a partículas finas inaláveis pode aumentar a inflamação das vias aéreas e posterior inflamação sistêmica nos pacientes com lúpus eritematoso sistêmico juvenil / Systemic lupus erythematosus is an inflammatory multisystem, autoimmune disease with elevated inflammatory interleukins levels. Exposure to air pollution may trigger pulmonary inflammation/systemic inflammation. Objective: The objective of this study was to investigate the association between daily individual exposure to air pollutants and airway inflammation and disease activity in childhood-onset systemic lupus erythematosus patients. A longitudinal panel study was carried out in 108 consecutive appointments with childhood-onset systemic lupus erythematosus patients without respiratory diseases. Methods: Over four consecutive weeks, daily individual measures of nitrogen dioxide, fine particulate matter, ambient temperature, and humidity were obtained. This cycle was repeated every 2.5 months along 1 year, and cytokines of exhaled breath condensate (interleukins 6, 8, 17 and tumoral necrose factor-alpha), fractional exhaled nitrogen monoxide, and disease activity parameters were collected weekly. Specific generalized estimation equation models were used to assess the impact of these pollutants on the risk of Systemic Lupus Erythematous Disease Activity Index 2000 >= 8, exhaled breath condensate cytokines, and fractional exhaled nitrogen monoxide, considering the fixed effects for repetitive measurements. The models were adjusted for inflammatory indicators, body mass index, infections, medication, and weather variables. Results: An interquartile range increase in fine particulate matter 4-day moving average (18.12ug/m3) was associated with an increase of 0.05 pg/ml (95% CI 0.01; 0.09, p = 0.03) and 0.04 pg/ml (95% CI 0.02; 0.06, p = 0.01) in interleukin 17 and tumoral necrosis factor-alpha exhaled breath condensate levels, respectively. Additionally, a short-term effect on fractional exhaled nitrogen monoxide was observed: the fine particulate matter 3-day moving average was associated with a 0.75 ppb increase (95% CI 0.38; 1.29, p = 0.03) in fractional exhaled nitrogen monoxide. Also, an increase of 1.47 (95% CI 1.10; 1.84) in the risk of Systemic Lupus Erythematous Disease Activity Index 2000 >= 8 was associated with fine particulate matter 7-day moving average. Conclusion: Exposure to inhalable fine particles increases airway inflammation/pulmonary and then systemic inflammation in childhood-onset systemic lupus erythematosus patients
28

Applications and challenges in mass spectrometry-based untargeted metabolomics

Jones, Christina Michele 27 May 2016 (has links)
Metabolomics is the methodical scientific study of biochemical processes associated with the metabolome—which comprises the entire collection of metabolites in any biological entity. Metabolome changes occur as a result of modifications in the genome and proteome, and are, therefore, directly related to cellular phenotype. Thus, metabolomic analysis is capable of providing a snapshot of cellular physiology. Untargeted metabolomics is an impartial, all-inclusive approach for detecting as many metabolites as possible without a priori knowledge of their identity. Hence, it is a valuable exploratory tool capable of providing extensive chemical information for discovery and hypothesis-generation regarding biochemical processes. A history of metabolomics and advances in the field corresponding to improved analytical technologies are described in Chapter 1 of this dissertation. Additionally, Chapter 1 introduces the analytical workflows involved in untargeted metabolomics research to provide a foundation for Chapters 2 – 5. Part I of this dissertation which encompasses Chapters 2 – 3 describes the utilization of mass spectrometry (MS)-based untargeted metabolomic analysis to acquire new insight into cancer detection. There is a knowledge deficit regarding the biochemical processes of the origin and proliferative molecular mechanisms of many types of cancer which has also led to a shortage of sensitive and specific biomarkers. Chapter 2 describes the development of an in vitro diagnostic multivariate index assay (IVDMIA) for prostate cancer (PCa) prediction based on ultra performance liquid chromatography-mass spectrometry (UPLC-MS) metabolic profiling of blood serum samples from 64 PCa patients and 50 healthy individuals. A panel of 40 metabolic spectral features was found to be differential with 92.1% sensitivity, 94.3% specificity, and 93.0% accuracy. The performance of the IVDMIA was higher than the prevalent prostate-specific antigen blood test, thus, highlighting that a combination of multiple discriminant features yields higher predictive power for PCa detection than the univariate analysis of a single marker. Chapter 3 describes two approaches that were taken to investigate metabolic patterns for early detection of ovarian cancer (OC). First, Dicer-Pten double knockout (DKO) mice that phenocopy many of the features of metastatic high-grade serous carcinoma (HGSC) observed in women were studied. Using UPLC-MS, serum samples from 14 early-stage tumor DKO mice and 11 controls were analyzed. Iterative multivariate classification selected 18 metabolites that, when considered as a panel, yielded 100% accuracy, sensitivity, and specificity for early-stage HGSC detection. In the second approach, serum metabolic phenotypes of an early-stage OC pilot patient cohort were characterized. Serum samples were collected from 24 early-stage OC patients and 40 healthy women, and subsequently analyzed using UPLC-MS. Multivariate statistical analysis employing support vector machine learning methods and recursive feature elimination selected a panel of metabolites that differentiated between age-matched samples with 100% cross-validated accuracy, sensitivity, and specificity. This small pilot study demonstrated that metabolic phenotypes may be useful for detecting early-stage OC and, thus, supports conducting larger, more comprehensive studies. Many challenges exist in the field of untargeted metabolomics. Part II of this dissertation which encompasses Chapters 4 – 5 focuses on two specific challenges. While metabolomic data may be used to generate hypothesis concerning biological processes, determining causal relationships within metabolic networks with only metabolomic data is impractical. Proteins play major roles in these networks; therefore, pairing metabolomic information with that acquired from proteomics gives a more comprehensive snapshot of perturbations to metabolic pathways. Chapter 4 describes the integration of MS- and NMR-based metabolomics with proteomics analyses to investigate the role of chemically mediated ecological interactions between Karenia brevis and two diatom competitors, Asterionellopsis glacialis and Thalassiosira pseudonana. This integrated systems biology approach showed that K. brevis allelopathy distinctively perturbed the metabolisms of these two competitors. A. glacialis had a more robust metabolic response to K. brevis allelopathy which may be a result of its repeated exposure to K. brevis blooms in the Gulf of Mexico. However, K. brevis allelopathy disrupted energy metabolism and obstructed cellular protection mechanisms including altering cell membrane components, inhibiting osmoregulation, and increasing oxidative stress in T. pseudonana. This work represents the first instance of metabolites and proteins measured simultaneously to understand the effects of allelopathy or in fact any form of competition. Chromatography is traditionally coupled to MS for untargeted metabolomics studies. While coupling chromatography to MS greatly enhances metabolome analysis due to the orthogonality of the techniques, the lengthy analysis times pose challenges for large metabolomics studies. Consequently, there is still a need for developing higher throughput MS approaches. A rapid metabolic fingerprinting method that utilizes a new transmission mode direct analysis in real time (TM-DART) ambient sampling technique is presented in Chapter 5. The optimization of TM-DART parameters directly affecting metabolite desorption and ionization, such as sample position and ionizing gas desorption temperature, was critical in achieving high sensitivity and detecting a broad mass range of metabolites. In terms of reproducibility, TM-DART compared favorably with traditional probe mode DART analysis, with coefficients of variation as low as 16%. TM-DART MS proved to be a powerful analytical technique for rapid metabolome analysis of human blood sera and was adapted for exhaled breath condensate (EBC) analysis. To determine the feasibility of utilizing TM-DART for metabolomics investigations, TM-DART was interfaced with traveling wave ion mobility spectrometry (TWIMS) time-of-flight (TOF) MS for the analysis of EBC samples from cystic fibrosis patients and healthy controls. TM-DART-TWIMS-TOF MS was able to successfully detect cystic fibrosis in this small sample cohort, thereby, demonstrating it can be employed for probing metabolome changes. Finally, in Chapter 6, a perspective on the presented work is provided along with goals on which future studies may focus.

Page generated in 0.0658 seconds