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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.
511

“Para seu intestino funcionar melhor, coma mais fibras e tome 2 litros de água por dia” : o que há de verdadeiro nesta recomendação?

Gonçalves, Gissele Vargas da Rosa January 2016 (has links)
Fundamento e objetivo: Mudanças na ingestão de fibra e água podem influenciar a fisiologia intestinal. Este conceito simplista fundamenta a recomendação médica popular de aumentar o consumo de fibras e ingerir 2 litros de água por dia para o tratamento da constipação intestinal. O nosso objetivo foi avaliar o que há de verdadeiro nesta recomendação, primeiramente em indivíduos saudáveis. Métodos: Neste ensaio clínico randomizado, não cego, de grupos paralelos, 20 voluntários sadios tiveram suas variáveis basais determinadas (dieta, hábito intestinal, qualidade de vida e microbiota intestinal), seguido de randomização para tratamentos de 14 dias com aumento na ingestão de fibras (grupo F) ou aumento de fibras acompanhado da ingestão de 2 litros de água por dia (grupo FA), repetindo-se a aferição das variáveis ao final. Resultados: Dezenove participantes foram analisados, sendo 10 no grupo F e 9 no grupo FA. A maioria dos participantes (68,4%) desenvolveu um ou mais sintomas abdominais, particularmente os do grupo F, em comparação ao FA (90% vs. 44%; P = 0,034). Participantes de ambos os grupos aumentaram significativamente o número de evacuações/semana (grupo F: 6,8 antes vs. 8,8 depois; grupo FA: 8,4 antes vs. 9,9 depois; P < 0,05), enquanto que apenas os participantes do grupo FA apresentaram aumento no peso bruto fecal (71,5 g vs. 126 g; P = 0,020) e no percentual de água nas fezes (74,5% vs. 78,4%; P = 0,038). A qualidade de vida mensurada pelo WHOQOL-Bref não diferiu em nenhuma intervenção. O tratamento com FA aumentou significativamente a população de bactérias do gênero Bacteroides e Prevotella, Faecalibacterium prausnitzii e Bifidobacteriums sp, enquanto que ambos FA e F reduziram a contagem das bactérias do gênero Desulfofibrio. Conclusões: Em voluntários sadios, o aumento no consumo de fibras e água melhorou o hábito intestinal, mas foi acompanhado de sintomas abdominais, particularmente quando o aumento na ingestão de fibras não foi acompanhado por aumento no consumo de água. O efeito na microbiota também foi superior no grupo tratado com fibra e água. / Background and aims: Intestinal physiology can be influenced by changes in fiber and water intake. This simple concept supports the recommendation of increasing fiber and water ingestion for treatment of bowel constipation. The aim of our study was to test whether such recommendation is true in healthy volunteers. Methods: In this open label clinical trial, 20 healthy participants had their basal characteristics determined (diet, bowel function, quality of life and intestinal microbiota), followed by randomization for 14 days treatment with increased fiber consumption (group F) or increased fiber and water intake (group FW), with reassessment of the variables at the end. Results: Nineteen participants were analyzed (10 F and 9 FW). The majority of them (68.4%) developed one or more abdominal symptoms during the treatments, particularly the group F as compared to FW (90% vs. 44%; P = 0.034). Both groups showed increased number of evacuations per week (group F: 6.8 before vs. 8.8 after; group FA: 8.4 vs. 9.9; P < 0.05), whereas group FW presented an increase in both fecal weight (71.5 g vs. 126 g; P = 0.020) and water percentage in feces (74.5% vs. 78.4%; P = 0.038). Quality of life measured by WHOQOL-Bref did not differ in any intervention. Participants receiving FW had a significant increase in bacteria from the Bacteroides and Prevotella genus, Faecalibacterium prausnitzii and Bifidobacterium, whereas both FW and F had a reduced number of Desulfofibrio. Conclusions: In healthy volunteers, a higher intake of fiber and water improved the bowel function but was accompanied by abdominal symptoms, particularly when the dietary fiber was introduced without changes in water intake. The effect on fecal microbiota was superior in participants treated with fiber and water.
512

Kvalita života pacientů s Crohnovou chorobou / Quality of life of patients with Crohn´s disease

RENDL, Lukáš January 2013 (has links)
Theoretical foundation Crohn's disease is a chronical autoimmune disease categorized, together with ulcerative colitis, in the group of idiopatic intestinal inflammations. But in spite of this categorization, Crohn's disease may not be found only in the intestines but anywhere in the gastrointestinal tract. However, the intestinal localization is most frequent and is related with numerous manifestations like stomachake, diarrhoea, bloating, flatulence, belching, loss of weight, etc. The pathogenetic cause of those discomforts consists in disorder of autoimmunity, when the body starts producing antibodies against its own tissues. But the cause of start of that pathogenetic mechanism has not been clarified so far. Experts speak about influence of infections, food, psychosomatics, smoking, genetic perceptiveness, etc. The hope of the patients is pinned on the continuously improving treatment, culminating by biological preparations that have most influenced the health condition of those persons so far. But in spite of the modern therapy, all characteristics of the disease can have negative impact on the quality of life of the patients. Goal of the thesis The goal of this thesis consists in ascertaining the quality of life of Crohn's disease patients. Hypotheses H1: Crohn's disease patients have problems in physical area. H2: Crohn's disease patients have problems in psychic area. H3: Crohn's disease patients have problems in social area. Methodology The practical part of the thesis was implemented based on quantitative inquiry within the grant Project No. 120/2012/S ?Reflection of life quality in nursing?. Two standardized questionnaires were used for the inquiry: the WHOQOL-100 general questionnaire and the IBDQ specific questionnaire, distributed among Crohn's disease patients. Valid licence was bought for both questionnaires. The size of the research set was determined at 100 Crohn's disease patients, the Crohn's disease diagnosis being the only criterion for selection of the respondents. The distribution of the questionnaires among the respondents took place with the help of gastroenterological centres. Results All data obtained were statistically processed in the SASD (Statistical Analysis of Social Data) program. The results of the processing can be divided into three areas, by the three main hypotheses verified. The first area of results provided information on the problems confronted by Crohn's disease patients in physical area. Only one problem was confirmed here: the Crohn's disease patients feel fatigue. All the remaining problems under verification in this area were refused. The second area brought information on psychical problems of the patients. Similarly to the preceding case, only one problem troubling the Crohn's disease patients was found here: feeling of irritation. The occurrence of the remaining psychical problems under verification was not confirmed. The last area of results found out the problems of the patients in social area. The results were the most positive in this case, as none of the problems under verification in this area was confirmed. Based on all results stated above, the hypotheses were evaluated as follows: H1 Crohn's disease patients have problems in physical area - refused; H2 Crohn's disease patients have problems in psychic area - refused and H3 Crohn's disease patients have problems in social area - refused. Conclusion The thesis provides comprehensive view on the issue of quality of life of Crohn's disease patients. The results may be used particularly in the work of so called IBD nurses, endoscopic nurses, but also general nurses working with the patients. The thesis can be also used as study material or as foundation for further research.
513

Biologická léčba u pacientů s nespecifickými střevními záněty / The biologic treatment of patiens with Inflammatory bowel diseases

BARTYZALOVÁ, Martina January 2014 (has links)
The thesis titled Biological Therapy in Patients with Inflammatory Bowel Diseases deals with the needs of clients with Crohn's disease and ulcerative colitis prior and after biological therapy. The role of nurses in biological therapy centres, including the application of this therapy, was also investigated. Crohn's disease and ulcerative colitis are inflammatory bowel diseases. They are chronic inflammatory diseases of the gastrointestinal tract, which are accompanied by ample extraintestinal symptoms. This thesis also deals with biological therapy that involves the administration of highly effective substances of biological nature that inhibit specific sites of inflammatory reactions. This therapy is provided in centres of biological therapy and is used not only in gastroenterology but also in rheumatology and oncology. Teams of experts work in biological therapy centres; the task of these teams is to provide a comprehensive holistic health care. The thesis is divided into a theoretical part and an empirical part. The theoretical part focuses mainly on Crohn's disease, ulcerative colitis and biological therapy that helps patients suffering from these diseases. The methodological section employed qualitative research using in-depth semi-structured interviews with patients suffering from idiopathic inflammatory bowel diseases and with nurses who deal with these patients when applying biological therapy. Since head nurses from gastroenterology departments did not wish to record the interviews with a recorder, they were recorded in writing and transcribed subsequently. The questions dealt with the issues of biological therapy in connection with inflammatory bowel diseases. All the acquired data was processed with the Atlas.ti programme, which is designed for encoding, processing and interpretation of large amounts of textual and graphic qualitative data. Based on the research, an educational brochure for patients suffering from inflammatory bowel diseases was complied as well as educational materials for nurses starting work in biological therapy centres. Furthermore, the results can be used by nurses in practice and nursing students too.
514

Inflammasome regulation and activation in the intestinal epithelium

Lei, Andrea January 2017 (has links)
Microbiota colonisation of the intestinal tract makes it difficult for pattern recognition receptors (PRR) to discriminate between beneficial microbes and harmful pathogens. We aim to define the roles of cytosolic Nod-like receptors (NLR) in intestinal immunity and homeostasis. Upon activation, some NLR form inflammasomes that mediate the release of inflammatory cytokines and pyroptosis, an inflammatory form of cell death. NLR activation in the non-hematopoietic compartment was shown to be protective during acute intestinal infection. To identify the cell type responsible for this protection, we generated transgenic mice in which the key inflammasome adaptor molecule Asc is selectively ablated in intestinal epithelial cells (IEC) (Asc<sup>ΔVC</sup>) and observed that inflammasomes are important for controlling Citrobacter rodentium clearance in these mice. To further dissect the importance of pathogen clearance by IEC inflammasome, ex vivo cultures of primary IEC organoids were established. Thus far this system has revealed profound differences in inflammasome regulation between IEC organoids and bone marrow-derived macrophages (BMDM). This research will inform our understanding of cell type-specific regulation of inflammasomes.
515

Influência da localização da enterocolite necrosante na mortalidade de recém-nascidos submetidos à laparotomia

Souza, Joao Carlos Ketzer de January 2008 (has links)
Objetivo: Avaliar a influência da localização da enterocolite necrosante neonatal na mortalidade de recém-nascidos (RN) submetidos à laparotomia exploradora. Métodos: Estudo de coorte prospectiva de 141 recém-nascidos com ECN submetidos consecutivamente à laparotomia exploradora no período de novembro de 1991 a dezembro de 2005. Foram avaliados dados epidemiológicos, localização e extensão da doença, crescimento intra-uterino e o número de óbitos no período de 60 dias após a cirurgia. Resultados: Setenta e quatro (52,5%) crianças eram do sexo masculino, com peso médio de nascimento de 1.589 ± 665 gramas, com idade gestacional média de 33,6 ± 2,9 semanas. Prematuridade ocorreu em 84,4% (119/141) dos RN. Cinqüenta e sete (40,4%) eram pequenos para a idade gestacional. Óbito ocorreu em 68 crianças (48,2%). Na análise bivariada, observou-se que o comprometimento do jejuno-íleo foi associado com alta mortalidade (20 óbitos - 76,9%; OR = 20; intervalo de confiança de 95% = 4,6 - 96,3; p < 0,001) e que a doença no jejuno estava associada à maior extensão da ECN. Entretanto, no modelo de regressão logística múltipla com controle individual de cada variável, a doença no jejuno-íleo (OR = 0,61; intervalo de confiança de 95% = 0,06 - 6,14; p = 0,68) e no intestino grosso (OR = 2,91; intervalo de confiança de 95% = 0,81 - 10,50; p = 0,10) não foram consideradas fatores de risco para o óbito. Conclusões: Em análise adequada, com controle isolado de cada variável estudada, a mortalidade foi independente da localização da ECN no intestino delgado ou no intestino grosso. Porém, a localização da doença no jejuno foi um marcador de maior extensão da ECN e, conseqüentemente, de pior prognóstico. Extensão difusa da doença e recém-nascidos PIG foram os mais importantes fatores de risco de ocorrência de óbito nesses recém-nascidos submetidos à cirurgia. / Aim of the study: To evaluate the effect of disease site on the mortality rate of newborns with necrotizing enterocolitis (NEC) undergoing exploratory laparotomy. Methods: Prospective cohort of 141 consecutive newborns with NEC who underwent laparotomy from November 1991 to December 2005. The study variables included epidemiologic data, disease site and extent, intrauterine growth, and number of deaths in the 60 days after operation. The protocol was approved by the institution’s Research Ethics Committee. Main results: Seventy-four (52.5%) infants were male. Mean birth weight was 1,589 ± 665 g, and mean gestational age was 33.6 ± 2.9 weeks. One-hundred and nineteen (84.4%) newborns were premature. Small for gestational age was observed in 57 (40.4%). Sixty-eight (48.2%) infants died. Bivariate analysis revealed that involvement of the jejunum and ileum was associated with high mortality rates (20 deaths, 76.9%; OR = 20; 95% 95% CI = 4.6 – 96.3; p < 0.001), and that involvement of the jejunum was associated with greater disease extent. After controlling for individual variables, logistic regression showed that the mortality associated with jejunum and ileum involvement (OR = 0.61; 95% CI = 0.06 - 6.14; p = 0.68) did not differ from that associated with large bowel involvement (OR = 2.91; 95% CI = 0.81 – 10.50; p = 0.10); however, jejunum involvement remained significantly associated with disease extent. Conclusions: NEC-related mortality in newborns undergoing laparotomy was not influenced by disease site (small or large bowel). However, jejunum involvement was a marker of greater disease extent and therefore of poor prognosis. Diffuse disease extent and small for gestational age were the most important markers of risk of death in NEC newborns submitted to surgery.
516

Incidência e Prevalência de Doenças Inflamatórias Intestinais no Estado de São Paulo - Brasil / Incidence and Prevalence of Inflammatory Bowel Diseases in the State of São Paulo – Brazil

Gasparini, Rodrigo Galhardi 23 February 2018 (has links)
Submitted by RODRIGO GALHARDI GASPARINI null (rggaspa@yahoo.com.br) on 2018-03-05T01:36:53Z No. of bitstreams: 1 Incidência e Prevalência de Doenças Inflamatórias Intestinais no Estado de Sâo Paulo - Brasil.pdf: 2020180 bytes, checksum: 64bba02d0cbc3e4d580ce7721fe858d7 (MD5) / Approved for entry into archive by Luciana Pizzani null (luciana@btu.unesp.br) on 2018-03-06T13:58:57Z (GMT) No. of bitstreams: 1 gasparini_rg_dr_bot.pdf: 2020180 bytes, checksum: 64bba02d0cbc3e4d580ce7721fe858d7 (MD5) / Made available in DSpace on 2018-03-06T13:58:57Z (GMT). No. of bitstreams: 1 gasparini_rg_dr_bot.pdf: 2020180 bytes, checksum: 64bba02d0cbc3e4d580ce7721fe858d7 (MD5) Previous issue date: 2018-02-23 / Introdução: As Doenças inflamatórias intestinais (DII), que tem como principais entidades a Retocolite Ulcerativa (RCU) e a Doença de Crohn (DC), tem altas taxas de incidência e prevalência em países desenvolvidos, especialmente da Europa e América do Norte, porém com aumento progressivo de sua frequência em todas os continentes. Este estudo visa estimar as taxas de incidência e prevalência das DII no Estado de São Paulo, Brasil, entre os anos de 2012 e 2015, e correlacionar os resultados com dados nacionais sobre estas doenças. Material e Método: Este é um estudo observacional analítico, do tipo descritivo e transversal. Foram incluídos dados epidemiológicos de 22.638 pacientes que iniciaram seu tratamento para Doença Inflamatória Intestinal através do programa de fornecimento gratuito de medicamentos do Estado de São Paulo, entre os anos de 2012 e 2015. As variáveis analisadas foram a data do início do tratamento, o diagnóstico clínico (DC ou RCU), a idade, gênero, cor/raça/etnia dos pacientes, assim como sua região de residência no Estado de São Paulo. As análises estatísticas incluíram média e desvio padrão para variáveis quantitativas. O nível de significância adotado foi de 1% Resultados: A taxa de incidência de DII no Estado de São Paulo foi, em média, de 13,31 casos novos / 100.000 habitantes / ano, enquanto a prevalência de DII no Estado de São Paulo foi de 52,5 casos / 100.000 habitantes. Os portadores de DC somavam 10.451 (46,16%), e os de RCU somavam 12.187 (53,83%), de 1 a 97 anos de idade, com média de 45,5 anos (DP = 16,7), sendo 9.124 (40,30%) do sexo masculino e 13.514 (59,70%) do sexo feminino. Conclusão: Este estudo demonstrou aumento das taxas de incidência e prevalência de Doenças Inflamatórias Intestinais no Estado de São Paulo. / Inflammatory bowel disease (IBD), which has as its main entities Ulcerative Colitis (UC) and Crohn's Disease (CD), have high rates of incidence and 11 prevalence in developed countries, especially in Europe and North America, but with increasing frequency in all continents. This study aims to verify the incidence and prevalence rates of IBD in São Paulo State, Brazil, between the years 2012 and 2015, and correlate with the national data on these diseases. Casuistic and Methods: This is an observational, descriptive and cross-sectional study. We included data from 22.638 patients who started their treatment for Inflammatory Bowel Disease through the Program of free medication supply of São Paulo State, between the years of 2012 and 2015. The variables analyzed were the date of beginning of treatment with drugs provided by the clinical diagnosis (CD or UC), the age, gender, color/race/ethnicity of the patients, as well as their region of residence in São Paulo State. Statistical analyses included mean and standard deviations for quantitative variables. The level of significance adopted was 1% Results: The incidence rate of IBD in the State of São Paulo was 13.31 new cases / 100.000 inhabitants per year, while the overall prevalence of IBD in the state of São Paulo was 52,5 cases/100.000 inhabitants. The patients with CD were 10,451 (46.16%), and those with UC were 12,187 (53.83%), from 1 to 97 years of age, with a mean of 45.5 years (SD = 16.7), of wich 9,124 (40.30%) were male and 13,514 (59.70%) were female. Conclusion: This study demonstrated an increase in the incidence and prevalence of Crohn's Disease and Ulcerative Colitis in the State of São Paulo.
517

Efeito das drogas Dexametasona e Azatioprina na viabilidade, morfologia e comportamento migratório de células-tronco mesenquimais

Schneider, Natália January 2014 (has links)
Glicocorticoides e outras drogas imunossupressoras são comumente utilizados para o tratamento de condições inflamatórias, como as Doenças Inflamatórias Intestinais (DIIs). Apesar dos avanços na terapia medicamentosa, a remissão da doença ainda é difícil de ser mantida. Devido às suas propriedades imunomodulatórias, as Células-Tronco Mesenquimais (MSCs – Mesenchymal Stem Cells) têm emergido como reguladoras da resposta imune, e sua viabilidade e propriedades migratórias são essenciais para o sucesso da terapia celular. Entretanto, pouco se conhece sobre os efeitos das drogas convencionalmente utilizadas no tratamento das DIIs no comportamento das MSCs. Portanto, o objetivo deste estudo foi avaliar a viabilidade, a morfometria nuclear, a polaridade celular, a distribuição da actina-F e da FAK (Focal Adhesion Kinase), e o comportamento migratório das MSCs na presença das drogas Azatioprina (AZA) e Dexametasona (DEXA). As células foram isoladas de membranas coriônicas humanas e caracterizadas pela diferenciação em adipócitos e osteócitos, bem como pela expressão de um painel de marcadores de superfície. As MSCs foram previamente tratadas com AZA ou DEXA por 24h ou 7d nas concentrações de 1μM ou 10μM, respectivamente. Ambas as drogas não afetaram a viabilidade celular analisada por MTT (3-(4,5-dimethyltiazol-2-yl)-2,5- diphenyltetrazolium bromide) e morfometria nuclear. Entretanto, a análise do índice de polaridade resultou em uma morfologia mais alongada após o tratamento com AZA, enquanto células mais arredondadas foram observadas na presença de DEXA. Os filamentos de actina foram marcados por Rodamina-Faloidina e sua análise mostrou que a AZA preservou parcialmente a formação de lamelipódios e aumentou a presença de fibras de estresse ventrais, enquanto que a DEXA inibiu a formação de lamelipódios, evidenciou uma maior presença de fibras de estresse ventrais e diminuiu a estabilidade das protrusões de membrana, observadas em vídeo. Através da análise de microscopia de série temporal, foi observado que as células sob o efeito da AZA por 7d migraram por maiores distâncias e tiveram um aumento em sua velocidade de migração (24,35%; P < 0,05; n = 4), ao passo que a DEXA diminuiu a velocidade migratória em 24h e 7d (-28,69% e -25,37%, respectivamente; P < 0.05; n = 4) e diminuiu a distância alcançada pelas células. Em conclusão, nossos dados sugerem que as drogas AZA e DEXA podem afetar diferentemente a morfologia e o comportamento migratório das MSCs, possivelmente afetando o resultado da terapia celular. O protocolo de migração celular utilizado neste estudo foi estabelecido por nosso grupo de pesquisa, sendo que um artigo científico contendo todas as etapas do protocolo foi escrito para que outros laboratórios possam utilizá-lo de maneira simples e eficaz. / Glucocorticoids and other immunosuppressive drugs are commonly used to treat inflammatory disorders, such as Inflammatory Bowel Disease (IBD) and, despite few improvements, the remission of IBD is still difficult to maintain. Due to its immunomodulatory properties, Mesenchymal Stem Cells (MSCs) have emerged as regulators of immune response, and its viability and activation of migratory properties are essential for a successful cell therapy. However, little is known about the effects of immunosuppressant drugs used on IBD treatment on MSCs behavior. In this way, the aim of this study was to evaluate MSCs viability, nuclear morphometry, cell polarity, F-actin and FAK (Focal Adhesion Kinase) distribution and cell migration properties in the presence of the immunosuppressive drugs Azathioprine (AZA) or Dexamethasone (DEX). MSCs were isolated from human chorionic membranes and characterized through adipogenic and osteogenic differentiations, as well as a panel of surface markers. Cells were previously treated with AZA or DEX for 24 hrs or 7 days at 1μM and 10μM, respectively. Both drugs had no effects on cell viability analyzed through MTT (3-(4,5- dimethyltiazol-2-yl)-2,5-diphenyltetrazolium bromide) and nuclear morphometry. However, polarity index analysis showed that AZA treatment induced a more elongated cell shape while a greater presence of rounded cells was observed under DEX exposure. F-actin was stained by Rhodamine-Phalloidin and showed that AZA could partially preserve lamellipodia formation and increase the presence of ventral actin stress fibers, while DEX inhibited lamellipodia formation and increased the presence of ventral actin stress fibers while decreasing protrusion stability, observed in video. Through time-lapse microscopy, it was observed that after 7 days of treatment, AZA improved cell the spatial trajectory (ST) and increased migration speed (24.35%, P < 0.05, n = 4) while DEX impaired ST and migration speed after 24 hrs and 7 days treatment (- 28.69% and -25.37%, respectively; P < 0.05, n = 4). In conclusion our data suggests these immunosuppressive drugs can differently affect MSCs morphology and migration capacity, possibly impacting the success of cell therapy. The migration protocol used in this study was successfully established by our group, leading to the writing of a protocol paper to facilitate the usage of this technique by other laboratories in a simple and efficient manner.
518

Análise de polimorfismos dos genes de enzimas de metabolização de detoxificação em doenças inflamatórias crônicas

Rech, Tássia Flores January 2013 (has links)
A doença inflamatória intestinal (DII) e a esclerose sistêmica (ES) são doenças inflamatórias crônicas de difícil diagnóstico e tratamento. A etiologia da DII e da ES ainda não é completamente compreendida, mas sabe-se que fatores genéticos, imunológicos e ambientais estão envolvidos na sua patogênese. A DII possui dois principais subtipos clínicos: a doença de Crohn (DC) e a retocolite ulcerativa (RCU), caracterizados pela inflamação do intestino delgado e/ou cólon. Evidências sugerem que o aumento do estresse oxidativo desempenha um papel importante na fisiopatologia da DII. A ES é uma doença inflamatória autoimune rara, caracterizada pela fibrose progressiva da pele e de órgãos internos. A hipótese de que o aumento do dano oxidativo pode iniciar o dano vascular e desencadear os eventos patológicos observados na ES vem sendo investigada. Genes e enzimas envolvidos na metabolização (Fase I) e detoxificação (Fase II) de xenobióticos são utilizados como marcadores de susceptibilidade para o desenvolvimento de doenças que possuem fatores ambientais como fatores de risco. Em uma reação de Fase I, as enzimas do Citocromo P450 (CYP) inserem um átomo de oxigênio em um substrato deixando-o eletrofílico e reativo, criando um sítio para posterior conjugação pelas enzimas de Fase II. As enzimas Glutationa S-tranferases (GST) de Fase II catalisam a conjugação da glutationa com uma grande variedade de compostos eletrofílicos, detoxificando substâncias endógenas e exógenas. A atividade catalítica aumentada das enzimas CYP, bem como a falha na detoxificação de metabólitos pelas GST pode contribuir para o aumento do estresse oxidativo. O objetivo deste estudo foi investigar o papel de polimorfismos nos genes que codificam enzimas de metabolização (CYP1A*2C e CYP2E1*5B) e detoxificação (GSTT1 nulo, GSTM1 nulo e GSTP1 Ile105Val) na susceptibilidade a estas doenças. O grupo de pacientes com DII era constituído por 235 indivíduos e o grupo controle por 241 indivíduos, todos eurodescendentes. Na ES, 122 pacientes (99 eurodescendentes e 23 afrodescendentes) e 329 controles (241 eurodescendentes e 87 afrodescendentes) foram analisados. Os polimorfismos CYP foram genotipados por PCR-RFLP, enquanto que os polimorfismos em GSTT1 e GSTM1 foram genotipados por PCR multiplex e PCR-RFLP para GSTP1. As frequências alélicas e genotípicas foram comparadas entre pacientes e controles usando o teste de Qui-Quadrado. A respeito dos resultados das análises em DII, as frequências alélicas e genotípicas dos polimorfismos CYP1A1*2C, CYP2E1*5B e GSTP1 Ile105Val, bem como as frequências genotípicas do polimorfismo de presença/ausência de GSTM1, foram similares nos três grupos de pacientes (DII, DC e RCU) quando comparados ao grupo controle (P>0,05). Observouse uma frequência significativamente aumentada do genótipo nulo de GSTT1 no grupo de pacientes com DII quando comparado ao grupo controle [0,28 vs 0,18; χ² com Yates P=0,02; OR=1,71 (IC 95% 1,09 –2,71)]. Quando separamos o grupo de pacientes em DC ou RCU, esta frequência permaneceu significativamente aumentada somente no grupo de pacientes com RCU comparado ao grupo controle [0,29 vs 0,18; χ² com Yates P=0,035; OR=1,84 (IC 95% 1,03 –3,24)]. Com relação aos resultados das análises na ES, uma frequência significativamente aumentada do genótipo *1A/*1A (P=0,03; 0,74 vs. 0,61) e do alelo *1A (P=0,013; 0,86 vs 0,78; OR=0,57, IC 95% 0,36–0,90) do polimorfismo CYP1A1*2C foi observada entre os indivíduos controles eurodescendentes. Em contrapartida, a frequência do alelo *2C estava significativamente aumentada entre os pacientes de mesma etnia (P=0,013; 0,22 vs 0,14; OR=1,75, IC 95% 1,11–2,74). Com relação às frequências alélicas e genotípicas dos polimorfismos CYP2E1*5B e GSTP1 Ile105Val, e as frequências genotípicas do polimorfismo de presença/ausência de GSTM1, nenhuma diferença significativa foi observada quando os grupos de pacientes de ambas as etnias foram comparados aos grupos controle (P>0,05). Uma frequência significativamente aumentada do genótipo nulo de GSTT1 [0,29 vs 0,18; χ² com Yates P=0,035; OR=1,85 (IC 95% 1,03–3,29)], bem como uma alta frequência da dupla deleção de GSTT1/GSTM1 [0,19 vs 0,08; χ² com Yates P=0,007; OR=2,62 (IC 95% 1,25 –5,46)], foi observada no grupo de pacientes comparado aos controles (eurodescendentes). Estas associações não se repetiram entre indivíduos afrodescendentes. Concluindo, nossos resultados sugerem que o genótipo nulo de GSTT1 está associado à susceptibilidade a DII e pode influenciar na definição do curso da doença para a RCU. Além disso, o genótipo nulo de GSTT1 sozinho ou em combinação com o genótipo nulo de GSTM1 é um fator genético de susceptibilidade para a ES, enquanto que o genótipo *1A/*1A ou a presença do alelo *1A do polimorfismo CYP1A1*2C pode exercer um papel protetor contra o desenvolvimento da ES em indivíduos eurodescendentes. / Inflammatory bowel disease (IBD) and systemic sclerosis (SSc) are chronic inflammatory diseases of difficult diagnosis and treatment. The etiology of IBD and SSc is not completely understood but it is known that genetic, immunologic and environmental factors are involved in its pathogenesis. Crohn’s disease (CD) and ulcerative colitis (UC) are the two major subtypes of IBD, characterized by inflammation of the small intestine and/or colon. Evidences suggest that the increase of oxidative stress plays an important role in the pathophysiology of IBD. SSc is a rare autoimmune inflammatory disease of the connective tissue characterized by progressive fibrosis of the skin and internal organs. The hypothesis that the increase of oxidative stress can initiate vascular damage and triggers the pathological events in SSc has been investigated. Genes and enzymes involved in metabolism (Phase I) and detoxification (Phase II) of xenobiotics are used as markers of susceptibility to the development of diseases that have environmental factors as risk factors. In a Phase I reactions, the Cytochrome P450 (CYP) enzymes insert an oxygen atom in a substrate that making it more electrophilic and reactive, and creating a site for subsequent conjugation by Phase II enzymes. Phase II Glutathione S-transferases (GSTs) enzymes catalyze the conjugation of glutathione with a variety of electrophilic compounds, detoxifying endogenous and exogenous substances. A higher catalytic activity of CYP enzymes, as well as the failure in detoxifying of metabolites by GST enzymes may to contribute for the increase of oxidative stress. The aim of this study was investigated the role of polymorphisms in genes coding Phase I enzymes (CYP1A*2C and CYP2E1*5B) and Phase II (GSTT1 null, GSTM1 null and GSTP1 Ile105Val) in susceptibility to these diseases. IBD group was constituted by 235 patients and the control group by 241 individuals, all European-derived. In SSc group, 122 patients (99 European-derived and 23 African-derived) and 329 controls (241 European-derived and 87 African-derived) were analyzed. The CYP polymorphisms were genotyped by PCR-RFLP, whereas polymorphisms in GSTM1 and GSTT1 were genotyped by multiplex PCR and PCRRFLP for GSTP1. Allelic and genotypic frequencies were compared between patients and controls using the Chi-square test. Concerning IBD, allelic and genotypic frequencies of CYP1A1*2C, CYP2E1*5B and GSTP1 Ile105Val polymorphisms, as well as genotypic frequencies of GSTM1 presence/absence polymorphism were similar in all groups patients (IBD, CD, and UC) and controls (P>0.05). We observed a significantly increased frequency of GSTT1 null genotype in IBD group as compared to controls [0.28 vs. 0.18, χ ² with Yates P=0.02, OR=1.71 (95% CI 1.09 – 2.71)]. When patients were classified in CD or UC group, this frequency remained significantly increased only among UC patients [0.29 vs. 0.18, χ ² with Yates P=0,035, OR=1.84 (95% CI 1.03 – 3.24)] as compared to controls. Regarding results in SSc, a frequency significantly increased of *1A/*1A genotype (P=0.03; 0.74 vs. 0.61) and *1A allele (P=0.013; 0.86 vs 0.78; OR=0.57, 95% CI 0.36–0.90) from CYP1A1*2C polymorphism was observed among European-derived controls. On the other hand, the frequency of *2C allele was significantly increased among patients of same ethnic group (P=0.013; 0.22 vs 0.14; OR=1.75, 95% CI 1.11–2.74). The allelic and genotypic frequencies of CYP2E1*5B and GSTP1 Ile105Val polymorphisms, as well as genotypic frequencies of GSTM1 presence/absence polymorphism were similar between SSc patients and controls of both ethnic groups (P>0.05). We observed a significantly increased frequency of GSTT1 null genotype [0.29 vs. 0.18, χ ² with Yates P=0.035, OR=1.85 (95% CI 1.03–3.29)], as well as an increased frequency of GSTT1/GSTM1 double-null in SSc patients as compared to controls [0.19 vs. 0.08; χ ² with Yates P=0.007, OR=2.62 (95% CI 1.25 – 5.46)]. These associations were exclusive to European-derived individuals. In conclusion, our results suggest that the GSTT1 null genotype is associated with susceptibility to IBD and may influence in defining the course of the disease for RCU. Furthermore, the GSTT1 null genotype alone or combined with GSTM1 null genotype is a susceptibility genetic factor to SSc, while the *1A/*1A genotype or the presence of *1A allele from CYP1A1*2C polymorphism may plays a protector role in SSc development in Brazilian Europeanderived individuals.
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Anti-oxidant Mn(II)-complexes : design and study in a cellular model of inflammatory diseases. Investigation of subcellular location / Complexes de manganèse(II) anti-oxydants : conception et étude sur un modèle cellulaires des maladies inflammatoires. Etude de localisation sub-cellulaire

Mathieu, Émilie 04 September 2017 (has links)
Les espèces réactives de l'oxygène (ROS) sont produites en continu dans tous les organismes aérobies et sont impliquées dans la signalisation cellulaire, les défenses contre les pathogènes, mais aussi le stress oxydant. Ce dernier correspond à un déséquilibre entre la production des ROS et leur prise en charge par les défenses anti-oxydantes de la cellule. Le stress oxydant est associé à de nombreuses pathologies, notamment les maladies inflammatoires chroniques de l'intestin (MICI). Parmi les métallo-enzymes qui contrôlent la concentration en ROS, les superoxide dismutases (SOD) jouent un rôle essentiel. Ces enzymes sont responsables de la régulation du superoxyde le premier ROS produit lors de la réduction du dioxygène. Dans ces travaux, des complexes de Mn(II) mimant l'activité de la Mn-SOD (SODm) ont été conçus en utilisant une approche biomimétique. Leur intérêt pour limiter le stress oxydant et l'inflammation dans un modèle cellulaire des MICI a été examiné. En particulier, leur activité biologique a été étudiée au vu de leurs propriétés physico-chimiques et de leur biodisponibilité. Les résultats obtenus avec un complexe parent ont mené à la conception d'une deuxième génération de SODm couplés à une sonde multimodale, à des peptides pénétrants, ou à des peptides adressant aux mitochondries. L'étude du complexe parent fonctionnalisé par des peptides polyarginines a démontré l'influence de charges positives portées par le ligand sur la constante de vitesse. Dans la continuité de l'approche biomimétique développée ici, la conception de SODm de novo est présentée et constitue un premier pas vers l'imitation de l'influence de la seconde sphère de coordination. / Reactive oxygen species (ROS) are produced continuously in all aerobic organisms and are involved in cell signaling, defenses against pathogens, but also oxidative stress. This latter corresponds to an imbalance between ROS production and their consumption by the antioxidant defenses of the cell. Oxidative stress is associated with numerous pathologies, such as inflammatory bowel diseases (IBD). Among the metalloenzymes controlling the concentration of ROS, superoxide dismutases (SOD) play a crucial role. These enzymes are responsibles for the regulation of superoxide, the first ROS produced by the reduction of oxygen. In this work, Mn(II) complexes mimicking the activity of the Mn-SOD (SODm) were designed using a biomimetic approach. Their relevance to limit oxidative stress and inflammation in a cellular model of IBD was investigated. In particular, their biological activity was studied in light of their physico-chemical properties and of their bioavailability. The results obtained with a parent complex led to the design of a second generation of SOD mimics conjugated with a single core multimodal probe, cell-penetrating peptides, or mitochondria-penetrating peptides. An effect of electrostatic interactions on the catalytic rate constant of the parent complex functionalized with polyarginines peptides was demonstrated, similarly to what is observed for the enzyme. In the continuity of the biomimetic approach envisioned here, the design of de novo SOD mimics is presented and constitutes a first step toward the mimicry of second sphere influence.
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Influência da localização da enterocolite necrosante na mortalidade de recém-nascidos submetidos à laparotomia

Souza, Joao Carlos Ketzer de January 2008 (has links)
Objetivo: Avaliar a influência da localização da enterocolite necrosante neonatal na mortalidade de recém-nascidos (RN) submetidos à laparotomia exploradora. Métodos: Estudo de coorte prospectiva de 141 recém-nascidos com ECN submetidos consecutivamente à laparotomia exploradora no período de novembro de 1991 a dezembro de 2005. Foram avaliados dados epidemiológicos, localização e extensão da doença, crescimento intra-uterino e o número de óbitos no período de 60 dias após a cirurgia. Resultados: Setenta e quatro (52,5%) crianças eram do sexo masculino, com peso médio de nascimento de 1.589 ± 665 gramas, com idade gestacional média de 33,6 ± 2,9 semanas. Prematuridade ocorreu em 84,4% (119/141) dos RN. Cinqüenta e sete (40,4%) eram pequenos para a idade gestacional. Óbito ocorreu em 68 crianças (48,2%). Na análise bivariada, observou-se que o comprometimento do jejuno-íleo foi associado com alta mortalidade (20 óbitos - 76,9%; OR = 20; intervalo de confiança de 95% = 4,6 - 96,3; p < 0,001) e que a doença no jejuno estava associada à maior extensão da ECN. Entretanto, no modelo de regressão logística múltipla com controle individual de cada variável, a doença no jejuno-íleo (OR = 0,61; intervalo de confiança de 95% = 0,06 - 6,14; p = 0,68) e no intestino grosso (OR = 2,91; intervalo de confiança de 95% = 0,81 - 10,50; p = 0,10) não foram consideradas fatores de risco para o óbito. Conclusões: Em análise adequada, com controle isolado de cada variável estudada, a mortalidade foi independente da localização da ECN no intestino delgado ou no intestino grosso. Porém, a localização da doença no jejuno foi um marcador de maior extensão da ECN e, conseqüentemente, de pior prognóstico. Extensão difusa da doença e recém-nascidos PIG foram os mais importantes fatores de risco de ocorrência de óbito nesses recém-nascidos submetidos à cirurgia. / Aim of the study: To evaluate the effect of disease site on the mortality rate of newborns with necrotizing enterocolitis (NEC) undergoing exploratory laparotomy. Methods: Prospective cohort of 141 consecutive newborns with NEC who underwent laparotomy from November 1991 to December 2005. The study variables included epidemiologic data, disease site and extent, intrauterine growth, and number of deaths in the 60 days after operation. The protocol was approved by the institution’s Research Ethics Committee. Main results: Seventy-four (52.5%) infants were male. Mean birth weight was 1,589 ± 665 g, and mean gestational age was 33.6 ± 2.9 weeks. One-hundred and nineteen (84.4%) newborns were premature. Small for gestational age was observed in 57 (40.4%). Sixty-eight (48.2%) infants died. Bivariate analysis revealed that involvement of the jejunum and ileum was associated with high mortality rates (20 deaths, 76.9%; OR = 20; 95% 95% CI = 4.6 – 96.3; p < 0.001), and that involvement of the jejunum was associated with greater disease extent. After controlling for individual variables, logistic regression showed that the mortality associated with jejunum and ileum involvement (OR = 0.61; 95% CI = 0.06 - 6.14; p = 0.68) did not differ from that associated with large bowel involvement (OR = 2.91; 95% CI = 0.81 – 10.50; p = 0.10); however, jejunum involvement remained significantly associated with disease extent. Conclusions: NEC-related mortality in newborns undergoing laparotomy was not influenced by disease site (small or large bowel). However, jejunum involvement was a marker of greater disease extent and therefore of poor prognosis. Diffuse disease extent and small for gestational age were the most important markers of risk of death in NEC newborns submitted to surgery.

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