• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 117
  • 40
  • 12
  • 3
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 214
  • 46
  • 35
  • 24
  • 17
  • 16
  • 16
  • 15
  • 12
  • 11
  • 11
  • 11
  • 11
  • 11
  • 10
  • 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.
201

Resultados do transplante multivisceral na trombose porto-mesentérica difusa / Outcomes of multivisceral transplantation in the setting of diffuse thromobisis of the portomesenteric venous

Rodrigo Martinez de Mello Vianna 18 December 2014 (has links)
Objetivo: Avaliar o prognóstico clínico do transplante multivisceral (TMV) na vigência de trombose difusa do sistema porto-mesentérico. Introdução. O transplante hepático (TH) na vigência de cirrose e trombose difusa do sistema porto-mesentérico é controverso e muitas vezes contraindicado em muitos centros de transplante hepático. O transplante hepático utilizando técnicas alternativas como a hemitransposição portocava falha na eliminação de complicações provenientes da hipertensão portal. O TMV substitui o fígado e todo o sistema venoso porto-mesentérico. Métodos: Uma base de dados de pacientes submetidos a transplante intestinal foi mantida com análise prospectiva de resultados. O diagnóstico de trombose difusa do sistema porto-mesentérico foi estabelecido através de tomografia abdominal em fases arterial e venosa, ou por ressonância magnética com reconstrução venosa. Resultados: Vinte e cinco pacientes com trombose de porta, estádio IV, foram submetidos ao TMV. Onze pacientes receberam transplante renal concomitante. Rejeição aguda confirmada por biópsia foi notada em cinco pacientes, que foram tratados com sucesso. Com um seguimento médio de 2,8 anos, a sobrevida de enxertos e pacientes foi de 80%, 72% e 72%, respectivamente. Até a presente data, todos os sobreviventes estão com boa função de enxerto e sem nenhum sintoma ou evidência de hipertensão portal. Conclusão: O TMV deve ser considerado como opção para o tratamento de pacientes com trombose portomesentérica difusa. O transplante multivisceral é o único procedimento que reverte completamente a hipertensão portal e a doença de base com uma sobrevida superior ao TH com reconstruções vasculares alternativas / Objective: To evaluate the clinical outcomes of multivisceral transplantation (MVT) in the setting of diffuse thrombosis of the portomesenteric venous system. Background: Liver transplantation (LT) in the face of cirrhosis and diffuse portomesenteric thrombosis (DPMT) is controversial and contraindicated in many transplant centers. LT using alternative techniques such as portocaval hemitransposition fails to eliminate complications of portal hypertension. MVT replaces the liver and the thrombosed portomesenteric system. Methods: A database of intestinal transplant patients was maintained with prospective analysis of outcomes. The diagnosis of diffuse PMT was established with dual-phase abdominal computed tomography or magnetic resonance imaging with venous reconstruction. Results: Twentyfive patients with grade IV DPMT received 25 MVT. Eleven patients underwent simultaneous cadaveric kidney transplantation. Biopsy proven acute cellular rejection was noted in 5 recipients, which was treated successfully. With a median follow-up of 2.8 years, patient and graft survival were 80%, 72%, and 72% at 1, 3, and 5 years, respectively. To date, all survivors have good graft function without any signs of residual/recurrent features of portal hypertension. Conclusions: MVT can be considered as an option for the treatment of patients with diffuse DPMT. MVT is the only procedure that completely reverses portal hypertension and addresses the primary disease, while achieving superior survival results in comparison to the alternative vascular reconstructions
202

Avaliação de uma nova técnica (TF-Test Modified) destinada ao diagnóstico de parasitoses intestinais em amostras fecais / Evaluation of a new technique (TF-Test Modified) intended for the diagnosis of intestinal parasites in fecal samples

Carvalho, Juliana Barboza, 1986- 23 August 2018 (has links)
Orientadores: Jancarlo Ferreira Gomes, Alexandre Xavier Falcão / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T15:19:46Z (GMT). No. of bitstreams: 1 Carvalho_JulianaBarboza_M.pdf: 1818938 bytes, checksum: d44ab358d0482575e52d1f77a3f4c07b (MD5) Previous issue date: 2013 / Resumo: As parasitoses intestinais são altamente prevalentes no mundo, estando entre as maiores causadoras de doenças e óbitos em seres humanos. Atualmente, o diagnóstico laboratorial destas parasitoses é realizado por meio de procedimentos técnicos manuais, desenvolvidos na sua grande maioria há décadas, o que justifica a aplicabilidade de técnicas mais sensíveis e práticas para esta finalidade, visando obter resultados eficientes, especialmente em programas governamentais direcionados à Saúde Pública. Sendo assim, o objetivo do projeto foi de avaliar e validar uma nova técnica parasitológica, denominada TF-Test Modified, em comparação com três técnicas parasitológicas convencionais consagradas pela literatura: TF-Test Conventional; Rugai, Mattos e Brisola; e Kato-Katz/Helm-Test. As etapas do trabalho consistiram em realizar coleta de material fecal de 457 indivíduos localizados em regiões endêmicas para parasitoses no município de Campinas, SP; no processamento laboratorial de 1.828 exames; no diagnóstico de 14 espécies parasitárias; e na análise estatística qualitativa de resultados de maneira abrangente. Dentre as espécies parasitárias encontradas, helmintos e protozoários intestinais foram detectados em 42,23% de indivíduos pela técnica de TF-Test Modified, ante 36,76% por TF-Test Conventional, 5,03% por Kato-Katz/Helm-Test, e 4,16% por Rugai, Mattos e Brisola. Destes casos, 54,40% de infecção simples dos indivíduos demonstrou serem portadores de monoparasitismo. A nova técnica parasitológica de TF-Test Modified, quando comparada com as demais técnicas, apresentou alto valor de infecção, como exemplo para dupla, tripla e múltipla, de maneira a perfazer um total de 98,37% de infecções. Ademais, a nova técnica apresentou índice Kappa com grau de concordância Quase Perfeito em todos os parâmetros avaliados com estimativa de 95% (P<0,05), permitiu encontrar com alta eficiência diagnóstica todas as espécies parasitárias estudadas, mostrou um notável diagnóstico verdadeiro, especialmente quando analisada comparativamente com as outras três técnicas convencionais. O atual estudo permitiu concluir que a técnica de TF-Test Modified pode ser utilizada de forma abrangente no diagnóstico qualitativo de protozoários e helmintos intestinais de humanos. O ganho de sensibilidade diagnóstica proporcionada por esta nova técnica deverá ser de estimável contribuição para o diagnóstico individual laboratorial, inquéritos populacionais e controle das parasitoses intestinais, de modo a repercutir em contribuição social / Abstract: Intestinal parasites are highly prevalent worldwide and is among the largest cause of illness and death in humans. Currently, the laboratory diagnosis of these parasites is accomplished through technical procedures manuals, developed mostly for decades, justifying the applicability of more sensitive techniques and practices for this purpose, to obtain effective results, especially in government programs aimed at Public Health. Thus, the objective of the project was to evaluate and validate a new technique parasite, called TF-Test Modified, compared with three conventional parasitological techniques enshrined in literature: TF-Test Conventional; Rugai, Mattos and Brisola, and Kato-Katz / Helm-Test. The steps of the work consisted of conducting a collection of fecal samples from 457 individuals located in regions endemic for parasitic infections in Campinas, SP, in laboratory processing of 1,828 examinations, the diagnosis of 14 parasitic species, and the qualitative statistical analysis of results so comprehensive. Among the species found parasitic, helminths and intestinal protozoa were detected in 42,23% of subjects using the technique of TF-Test Modified, against 36,76% by TF-Test Conventional, 5,03% by Kato-Katz/Helm-Test, and 4,16% Rugai, Mattos and Brisola. Of these cases, 54,40% of single infections of individuals were shown to be carriers of monoparasitism. The new technique parasitological TF-Test Modified compared to other techniques of infection showed a high value, for example double, triple and multiple so as to make a total of 98,37% infections . Moreover, the new technique presented Kappa index level of agreement with Almost Perfect in all parameters with estimated 95% (P <0.05), allowed to meet with high diagnostic efficiency all parasitic species studied showed remarkable true diagnosis, especially when viewed in comparison with other three conventional techniques. The current study showed that the technique TF-Test Modified can be used comprehensively in qualitative diagnosis of intestinal protozoa and helminths of humans. The gain in diagnostic sensitivity afforded by this new technique should be estimable contribution to the individual diagnostic laboratory, population surveys and control of intestinal parasites, in order to reflect on social contribution / Mestrado / Parasitologia / Mestra em Parasitologia
203

Study of the modulation of innate immune responses in intestinal epithelial cells by Toxoplasma gondii and its correlation with parasite virulence / Etude de la modulation des réponses immunitaires innées dans les cellules épithéliales intestinales par Toxoplasma gondii, et sa corrélation avec la virulence du parasite

Morampudi, Vijay 28 October 2010 (has links)
Early innate response of intestinal epithelial cells is the first line defense against enteric pathogens. Toxoplasma gondii infections acquired naturally via the peroral route, encounter intestinal epithelial cells early post-infection. Although the population structure of T. gondii is known to be highly clonal, clinical strains of T. gondii have been classified into three genotypes based on their virulence. In this study we investigated whether human intestinal epithelial cell immune response to T. gondii is virulence dependent. We demonstrated distinct virulence of the three T. gondii genotype strains evaluated in human intestinal epithelial cells by their capacity to replicate and induce host cell cytotoxicity. The early host innate mechanisms such as activation of signaling pathways and induction of innate effectors were likewise differentially elicited by the three T. gondii strains. Low levels of TLR dependent NF-kB activation and a failure to rapidly up-regulate innate cytokine and chemokine genes was observed after virulent Type I strain infection. In contrast, early innate response to the less virulent Type II strain was rapid, efficient and led to high levels of IL-8 and IL-6 secretion, whereas response to Type III parasites was intermediate. Early expression of b-defensin 2 gene was suppressed specifically by virulent Type I strain and its activation prior to infection in intestinal epithelial cells led to decreased parasite viability. These findings provide evidence for T. gondii strain virulence dependent down-modulation of early human intestinal epithelial cell innate responses and highlight the importance of these cells in host defense against this infection. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
204

Characterization of Growth Hormone's Role on the Gut Microbiome

Jensen, Elizabeth A. 22 September 2020 (has links)
No description available.
205

Detection of Cryptosporidium species in stools of HIV/AIDS patients in Bela-Bela, South Africa

Makuwa, Stenly Modupi 06 1900 (has links)
MSc (Microbiology) / Department of Microbiology / See the attached abstract below
206

The Effects of Air Pollution on the Intestinal Microbiota: A Novel Approach to Assess How Gut Microbe Interactions with the Environment Affect Human Health

Fitch, Megan N. 05 1900 (has links)
This thesis investigates how air pollution, both natural and anthropogenic, affects changes in the proximal small intestine and ileum microbiota profile, as well as intestinal barrier integrity, histological changes, and inflammation. APO-E KO mice on a high fat diet were randomly selected to be exposed by whole body inhalation to either wood smoke (WS) or mixed vehicular exhaust (MVE), with filtered air (FA) acting as the control. Intestinal integrity and histology were assessed by observing expression of well- known structural components tight junction proteins (TJPs), matrix metallopeptidase-9 (MMP-9), and gel-forming mucin (MUC2), as well known inflammatory related factors: TNF-α, IL-1β, and toll-like receptor (TLR)-4. Bacterial profiling was done using DNA analysis of microbiota within the ileum, utilizing 16S metagenomics sequencing (Illumina miSeq) technique. Overall results of this experiment suggest that air pollution, both anthropogenic and natural, cause a breach in the intestinal barrier with an increase in inflammatory factors and a decrease in beneficial bacteria. This evidence suggests the possibility of air pollution being a potential causative agent of intestinal disease as well as a possible contributing mechanism for induction of systemic inflammation.
207

Influence of pathogenic bacterial determinants on genome stability of exposed intestinal cells and of distal liver and spleen cells

Walz, Paul S January 2011 (has links)
Most bacterial infections can be correlated to contamination of consumables such as food and water. Upon contamination, boil water advisories have been ordered to ensure water is safe to consume, despite the evidence that heat-killed bacteria can induce genomic instability of exposed (intestine) and distal cells (liver and spleen). We hypothesize that exposure to components of heat-killed Escherichia coli O157:H7 will induce genomic instability within animal cells directly and indirectly exposed to these determinants. Mice were exposed to various components of dead bacteria such as DNA, RNA, protein or LPS as well as to whole heat-killed bacteria via drinking water. Here, we report that exposure to whole heat-killed bacteria and LPS resulted in significant alterations in the steady state RNA levels and in the levels of proteins involved in proliferation, DNA repair and DNA methylation. Exposure to whole heat-killed bacteria and their LPS components also leads to increased levels of DNA damage. / xiv, 132 leaves : ill. (chiefly col.) ; 29 cm
208

Identification of downstream targets of ALK signaling in Drosophila melanogaster /

Varshney, Gaurav, January 2008 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2008. / Härtill 5 uppsatser.
209

Intestine Homeostasis and the Role of Tumor Suppressor Gene 101 in Drosophila Melanogaster: A Dissertation

Chatterjee, Madhurima 21 December 2011 (has links)
Tissue homeostasis in the adult Drosophila melanogaster intestine is maintained by controlling the proper balance of stem cell self-renewal and differentiation. In the adult fly midgut, intestinal stem cells (ISCs) are the only dividing cells and their identity maintenance is crucial to the proper functioning of the fly gut. Various pathways such as Notch, JAK-STAT and Wingless are known to regulate ISC division and differentiation. Here I used a pathogen feeding model to study conditions that accelerate ISC division and guide intestinal cell differentiation favoring enterocyte development. I also examined the role of Tumor Suppressor Gene 101 (TSG101) in ISC maintenance and function. TSG101, a part of the ESCRT1 complex. It is known to stimulate the Notch pathway and to play a role in endocytic trafficking. TSG101 loss-of-function mutants show developmental defects in various fly and mammalian tissues. The protein also plays a role in virus abscission from host cells. In my experiments I have observed that TSG101 is required for ISC maintenance. TSG101 knockdown and loss of function mutant clones have defects in ISC proliferation that hinder the normal intestinal responses to oral pathogen ingestion. Based on these results I conclude that TSG101 is needed in the adult fly intestine for proper ISC maintenance and function, thereby being an important player in intestinal homeostasis.
210

Influence du diabète de type 2 sur l’activité et l’expression des cytochromes P450

Gravel, Sophie 03 1900 (has links)
Mon projet de doctorat a pour objet l'étude des facteurs pouvant influencer le métabolisme des médicaments et la variabilité interindividuelle dans la réponse aux médicaments. Mon projet cible plus précisément les Cytochromes P450 (CYP450), le système enzymatique majeur impliqué dans la biotransformation des médicaments. Mes travaux de recherche évaluent l'impact d’une condition pathologique, le diabète de type 2 (DT2), sur l'activité métabolique des CYP450s. Mes études comprennent un volet de métabolisme systémique chez le patient et un volet de métabolisme in vitro. Dans cette thèse, les résultats de mes recherches sont rapportés sous forme de présentation par articles. Le volet in vivo consistait en une étude de pharmacocinétique qui visait à évaluer l’impact du diabète sur l’activité métabolique de différentes isoformes des CYP450s en utilisant un cocktail de substrats-marqueurs. Des patients avec le DT2 et des sujets non diabétiques ont reçu une dose orale de notre cocktail VM/JT de substrats-marqueurs composé de caféine (CYP1A2), bupropion (CYP2B6), tolbutamide (CYP2C9), oméprazole (CYP2C19), dextrométhorphane (CYP2D6) et midazolam (CYP3A4/5) suivi d'une administration de chlorzoxazone (CYP2E1). Le protocole pour cette étude est détaillé dans l’article disponible à la section 2.1; manuscrit 1. Les concentrations plasmatiques et urinaires des médicaments marqueurs et de leurs métabolites spécifiques ont été quantifiées par LC-MS/MS suivant la méthode publiée dont l’article est disponible à l’annexe 1. Cette étude m’a permis de montrer que les patients avec le DT2 présenteraient une clairance systémique réduite via les isoformes CYP2B6, CYP2C19 et CYP3A. L’article présentant ces résultats se trouve à la section 2.1; manuscrit 2. Au cours de cette étude clinique, nous avons aussi évalué l’utilisation du 4-hydroxycholestérol comme biomarqueur endogène de l’activité du CYP3A dans une population avec le DT2 (objectif secondaire). Les conclusions démontrant la validité de ce biomarqueur sont disponibles dans l’article qui se trouve à la section 2.2; manuscrit 3. Le volet in vitro de mes travaux a permis d’évaluer au niveau du duodénum l’influence du DT2 sur l’expression de plusieurs CYP450s et transporteurs, ainsi que sur l’activité des CYP2B6, CYP2C9, CYP2J2 et CYP3A. Aucun impact significatif du DT2 n’a été mesuré sur l’expression d’ARNm des CYP450s et transporteurs testés exprimés dans des biopsies duodénales. Les niveaux d’activité mesurés à l’aide d’incubations avec des substrats-marqueurs des CYP450s dans des fractions S9 de biopsies duodénales étaient semblables chez des sujets avec le DT2 et des non diabétiques. L’article sur les résultats de ce volet in vitro est disponible à la section 2.3; manuscrit 4. Ces résultats suggèrent que les effets du diabète sur le métabolisme des substrat-marqueurs observés dans l’étude clinique peuvent s’expliquer par une modulation au niveau hépatique ou dans différentes sections de l’intestin. En accord avec ces résultats chez l’humain, notre groupe avait déjà rapporté que l’effet du diabète sur les CYP450s était isoforme et tissu spécifique chez la souris (annexe 2). L'objectif de ma thèse était de mieux comprendre les mécanismes sous-jacents à la variabilité dans la réponse aux médicaments observés chez les patients diabétiques, lesquels nécessitent fréquemment une polypharmacie. Les résultats de ces travaux permettront éventuellement d’optimiser la pharmacothérapie chez ces patients. / My PhD project evaluates factors that can influence drug metabolism and interindividual variability in drug response. More precisely, my thesis focuses on the major drug metabolizing enzymes, the cytochromes P450 (CYP450). My researches evaluated the impact of a pathological condition, namely type 2 diabetes (T2D), on CYP450 metabolic activities in two parts. First, the effect of diabetes on systemic metabolism was evaluated in patients. Then, in vitro experiments enabled us to measure the impact of T2D on organ-specific or metabolism. In this thesis, my research results are presented in 4 scientific papers. The in vivo part of my PhD research consisted of a pharmacokinetic study assessing metabolic activity of different isoforms of the CYP450s using a cocktail of probe drugs in T2D patients and non-diabetic subjects. All participants of both study groups received a dose of our oral VM/JT probe drugs cocktail consisting of caffeine (CYP1A2), bupropion (CYP2B6), tolbutamide (CYP2C9), omeprazole (CYP2C19), dextromethorphan (CYP2D6) and midazolam (CYP3A4/5) followed by a dose of chlorzoxazone (CYP2E1), alone. Study procedures are detailed in the protocol article (manuscrit 1) presented in section 2.1. Plasma and urine concentrations for all probe drugs and specific metabolites were quantified using a published LC-MS/MS method that is available in annexe 1. This study showed that patients with T2D exhibited reduced systemic clearances for the isoforms CYP2B6, CYP2C19 and CYP3A. Results of this pharmacokinetic research are presented in manuscrit 2 of section 2.1. As a secondary objective, this in vivo part of my PhD project enabled us to verify the validity of 4-hydroxycholesterol as an endogenous biomarker of CYP3A activity in a population with T2D. Conclusions showing its validity as an endogenous biomarker in such population are presented in section 2.2 (manuscrit 3). The in vitro part of my doctoral project evaluated in the intestines the influence of T2D on the mRNA expression of numerous CYP450 isozymes and drug transporters, as well as on metabolic activity of CYP2B6, CYP2C9, CYP2J2 and CYP3A. Using duodenal biopsies, no significant impact of T2D was detected on the mRNA expression levels of all tested CYP450s and transporters. Activity levels measured following incubations of probe-substrates in S9 fractions of duodenal biopsies obtained from patients with T2D and non-diabetic patients were similar. Results from this in vitro study are reported in section 2.3 (manuscrit 4) of this thesis. These results obtained in human subjects are in agreement with our previously published results showing isoform- and tissue-specific effects of T2D on CYP450s in mice (annexe 2). Overall, the central theme of this thesis is to better understand the underlying mechanisms of drug response variability observed in diabetic patients, whom often require polypharmacy, in order to eventually optimize drug therapy in those patients.

Page generated in 0.016 seconds