• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 315
  • 147
  • 93
  • 41
  • 16
  • 16
  • 13
  • 9
  • 9
  • 9
  • 9
  • 9
  • 9
  • 8
  • 7
  • Tagged with
  • 807
  • 213
  • 180
  • 157
  • 134
  • 118
  • 117
  • 103
  • 86
  • 85
  • 66
  • 64
  • 63
  • 54
  • 54
  • 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.
471

Tratamento do megaesôfago avançado pela esofagogastroplastia: avaliação clínica e estudo da secreção ácida do estômago e dos níveis séricos do pepsinogenio e da gastrina / Surgical treatment of End Stage Achalasia by subtotal esophagectomy with gastric pull-up: clinical evaluation and study of gastric acid secretion , serum gastrin and pepsinogen levels

Rocha, Julio Rafael Mariano da 16 May 1986 (has links)
O autor estudou prospectivamente a evolução clínica e a função secretora e hormonal 90 estômago em quinze pacientes portadores de rnegaesôfago chagásico avançado, antes e seis meses após o tratamento cirúrgico pela esofagectornia subtotal associada a esofagogastroplastia com anastomose esofa gogástrica cervical e piloroplastia. A evolução clínica pós-operatória, foi segui- da com avaliaçôes a cada dois meses, durante os seis meses es tudados neste tratabalho. Houve resolução da síndrome disfágicã, apos o tratamento cirúrgico, com exceção de um paciente em que ape- sar da melhora evidente, persistiu disfagia discreta. Consta tou-se ainda aumento significativo do peso corporeo, notada- mente nos pacientes que apresentavam maior dãficit ponderal. A diarrãia,que não esteve presente no período pré-operatório, foi constatada no pós-operatório, em nível si~ nificante, até os seis meses considerados neste estudo, porem com discreta intensidade, a partir do terceiro mês de evolução. Esta manifestação foi interpretada como conseqüência da VT e piloroplastia. No período pós-operatório, o estômago trans- posto ao mediastino, tomou forma alongada com pregas mucosas de disposição longitudinal, porém com moderada dilatação na porção distal em três casos. Houve redução significativa do TEG, no período pós-operatório. Os valores médios da acidimetria, em condição basal e apos estimulação com pentagastrina, no período pré-operatório, foram inferiores aos valores obtidos em indivíduos DOr mais, nas mesmas condições. Seis meses após a realização do tratamento cirúrgico, houve diminuição significativa dos valo- res médios da acidimetria após estimulação com pentagastrina, sem no entanto- se alterarem significativamente os referidos va lores, em condição basal. Os valores médios da acidimetria, apos estimulação com pentagastrina,apresentavam aumento significativo quan do comparados aos valores médios obtidos em condição tanto antes- como após o tratamento cirúrgico. Os valores médios dos niveis séricos do pepsnogênio, tanto em condição basal, como após estimulação com Betazole R aos 60, 90 e 120 minutos, diminuiram significativa- mente no período pós-operatórioíquando comparados às médias dos niveis pré-operatórios. Os valores médios dos niveis séricos do pepsnogênio, obtidos após estimulação com BetazoleR aos 60, 90 e 120 minutos, apresentaram aumento significativo quando compara dos aos valores obtidos em condição basal, tanto no pre como no pós-operatório período. No periodo pré-operatório, os valores médios dos niveis séricos da gastrina, em condição basal, apresenta- ram aumento significativo quando comparados aos valores obti dos em individuos normais, nas mesmas condições. o valor médio da gastrinemia, em condição basal, mostrou-se significativamente aumentado no periodo pós-operatório, quando comparado ao valor obtido no pré-operatório, nas mesmas condições / Clinical evolution and secretory and hormonal gastric functions were prospectively studied in fifteen - patients with advanced megaesophagus consequent to Chagas disease. Stu dies were carried out before and up to six months after surgi- cal treatment by subtotal esophagectomy associated with gastr9 plasty, cervical gastroesophageal anastomosis and pyloroplasty. Complete postoperative resolution of the dis phagic syndrome was observed in alI patients except one, who was evidently relieved but still complained of some disphagia. Significant postoperative body weight increase was also registered, specially in those patients who exhibited preoperative larger body weight deficit. Diarrhea was never present before the opera- tion. Postoperative diarrhea, however, occurred significantly up to the six months included in this study, but i t was of mild degree from the third month on. This symptom was atributed to vagatomy and pyloroplasty. In the radiological postoperative studies the stomach in mediastinal position assumed an alongated shape, with longitudinal mucosal folds, but with moderate distal enlargement in three cases. There was significant reduction in the time of gastric emptying after the operation. Preoperative mean vaIues of gastric acid secretion in basal condition and after stimuIation with pentaga trin were Iower than observed in normal controls in the same conditions. Six months after surgery there was significant reduction of the mean values after stimulation, with pentagastrin. However, no significant variation was observed in basal condition. Mean values after stimulation with pentagastrin w re significantly higher than in basal condition before as well as after the operation. Mean values of serum pepsinogen levels in basal condition, as well as after, stimuIation with Betazole, at 60, 90 and 120 minutes, were significantIy reduced in the post operative period when compared to the preoperative correspon- dents Ievels. Mean values after stimuIation with Betazole we re siginificantly higher than in basal condition, before as weIl as after the operation. Preoperative mean values of ser um gastrin levels in basal condition were significantly higher than in normal controls in the same conditions. The mean value of basaI serum gastrin increased significantly after the operation, in comparison:with preoperative vaIue in the same condition
472

The role of DNA-dependent protein kinase in tumor metastasis / Le rôle de la protéine kinase dépendante de l’ADN (DNA-PK) dans le processus métastatique

Kotula, Ewa 28 May 2014 (has links)
La protéine kinase dépendante de l’ADN (DNA-PK) est une sérine-thréonine kinase qui est un élément essentiel dans la voie de réparation de l’ADN endommagé par recombinaison non-homologue (non-homologous end-joining; NHEJ). DNA-PK est également impliquée dans de nombreux processus cellulaires autre que la réparation de l'ADN. Plusieurs travaux ont montré que les protéines impliquées dans la réparation des dommages de l'ADN tels que BRCA-1, MRN-11, PARP-1 et également de DNA-PK jouent un rôle important dans la métastase du cancer. Dans ce travail, nous nous sommes concentrées sur le rôle de DNA-PK dans les métastases du mélanome. Dans un premier temps, en utilisant les molécules Dbait 32Hc comme un moyen d'activer DNA-PK dans le noyau et le cytoplasme, nous avons identifié plusieurs nouvelles cibles cytoplasmiques de DNA-PK, dont la vimentine. Nous avons montré que DNA-PK phosphoryle la vimentine sur Ser459 et que cette forme phosphorylée est la plupart du temps située au niveau des protrusion cellulaires des cellules migratrices. Nous avons ensuite démontré que la vimentine-Ser459-P induite par le traitement de Dbait32Hc participe à l'inhibition de l'adhésion et la migration cellulaire. Ainsi, cette approche a conduit à l'identification de nouvelles cibles cytoplasmiques de DNA-PK et a révélé un lien entre la signalisation des dommages de l'ADN et le cytosquelette. Ensuite, nous avons montré que DNA-PK joue un rôle important dans la migration et invasion cellules en régulant la sécrétion des facteurs associés à la métastase. Nous avons montré que l'absence ou l’inhibition de DNA-PK conduit à une régulation négative des facteurs pro-métastatique sécrétés et à la régulation positive de facteurs anti-métastatiques sécrétés tels que les inhibiteurs des métalloprotéinases matricielles. Nous avons confirmé le rôle de DNA-PK in vivo dans l'implantation de la tumeur primaire et dans la formation des métastases. Ainsi, nos études ont évalué le rôle de DNA-PK sur le contrôle du microenvironnement de la tumeur par le contrôle de la sécrétion de facteurs importants pour la métastase. En résumé, nos résultats mettent en évidence l'importance de la DNA-PK comme cible de traitement anti-métastatique. / The DNA-dependent protein kinase (DNA-PK) is a serine/threonine protein kinase, which is a critical component of the DNA-damage repair pathways through non-homologous end-joining (NHEJ). Besides DNA repair, it is also involved in numerous cellular pathways. Emerging results show that proteins involved in DNA damage repair such as BRCA-1, MRN-11, PARP-1 and also DNA-PK could play a role in cancer metastasis. In the current study, we demonstrated the role of DNA-PK in melanoma metastasis. Firstly using Dbait 32Hc molecules as a tool for specifically activating DNA-PK in a nucleus and cytoplasm, we identified several new cytoplasmic targets of DNA-PK including vimentin. We established that DNA-PK phosphorylates vimentin on Ser459 and that this phosphorylation was mostly located at cell protrusions of melanoma migratory cells. Following this, we confirmed that vimentin-Ser459-P induced by Dbait 32Hc treatment participates to the inhibition of cell adhesion and migration. Thus, this approach led to the identification of downstream cytoplasmic targets of DNA-PK and revealed a connection between DNA damage signaling and the cytoskeleton. Secondly, we show that DNA-PK plays an important role in cell migration and melanoma cell invasion through the regulation of secretion of metastasis-associated factors. Absence or inhibition of DNA-PK leads to down-regulation of pro-metastatic secreted factors and up-regulation of anti-metastatic secreted factors such as inhibitors of matrix metalloproteinases. We confirmed in vivo, that DNA-PK is required for efficient primary tumor implantation and metastases formation. Thus, our studies demonstrate for the first time that DNA-PK acts on tumor microenvironment by controlling secretion of important factors for cell migration and invasion. In summary, our findings highlight the importance of DNA-PK as a target of anti-metastatic treatment.
473

Vias de sinalização desencadeadas pela estimulação do adrenoceptor <font face=\"symbol\">b em células secretoras da glândula de veneno da serpente Bothrops jararaca. / Signaling pathways triggered by the stimulation of the <font face=\"symbol\">b adrenoceptor in secretory cells of the venom gland of the snake Bothrops jararaca.

Zablith, Mariana Bayerlein 08 October 2007 (has links)
O adrenoceptor <font face=\"symbol\">b está presente na glândula de veneno de Bothrops jararaca, tanto no estado quiescente como no ativado por 4 dias, entretanto, quando estimulado, aumenta os níveis de AMPc somente em células secretoras no estado quiescente. Neste trabalho, estudamos funcionalmente o adrenoceptor <font face=\"symbol\">b durante o ciclo de produção de veneno e verificamos a sua função. Mostramos que a estimulação do adrenoceptor <font face=\"symbol\">b promove aumento na taxa de acidificação do meio extracelular em células quiescentes e ativadas por 4 dias, mas não por 15 dias. Em células quiescentes, a estimulação do adrenoceptor <font face=\"symbol\">b também promove o influxo de cálcio, via canais operados por voltagem e por receptor e a liberação de cálcio de estoques intracelulares sensíveis a tapsigargina. Em células ativadas por 4 dias, o aumento de cálcio citosólico é significativamente menor do que em células quiescentes, confirmando a dessensibilização deste receptor. PKA não participa desta sinalização. Dados in vivo mostram que o adrenoceptor <font face=\"symbol\">b é importante para desencadear o ciclo de produção de veneno. / <font face=\"symbol\">b adrenoceptor is present in quiescent and 4 days activated secretory cells of venom gland of Bothrops jararaca snake, however its stimulation increase cAMP production only in quiescent cells. In this work, we functionally characterized <font face=\"symbol\">b adrenoceptor during the venom production cycle and verified its function in venom production. We showed that the stimulation of <font face=\"symbol\">b adrenoceptor increases the rate of extracellular acidification in quiescent and 4 days activated cells, but not in 15 days activated cells. In quiescent cells, <font face=\"symbol\">b adrenoceptor stimulation also triggers calcium influx through voltage-operated and receptor-operated calcium channels, and calcium release from tapsigargin-sensitive stores. In 4 days activated cells, <font face=\"symbol\">b adrenoceptor stimulation promotes smaller increases in citosolic calcium concentration than in quiescent cells, confirming that this adrenoceptor undergoes to dessensitization. PKA does not participate in calcium signaling. In vivo experiments showed that <font face=\"symbol\">b adrenoceptor is important to trigger the cycle of venom production.
474

Etude de la susceptibilité des cellules eucaryotes à l'injection de toxines par le système de sécrétion de type 3 de Pseudomonas aeruginosa / Study of the susceptibility of host cells to toxin injection by the type 3 secretion system of Pseudomonas aeruginosa

Verove, Julien 20 December 2011 (has links)
La pathogénicité de P. aeruginosa (P. a) repose sur de nombreux facteurs de virulence dont le système de sécrétion de type III (SST3). Ce complexe multiprotéique est constitué d'une aiguille se terminant par un translocon composé des protéines PopB et PopD. En s'insérant dans les membranes plasmiques, le translocon permet le passage des exotoxines dans le cytoplasme de la cellule cible. L'induction de la synthèse et de la sécrétion des exotoxines est dépendante d'un contact entre P. a et la cellule cible. Dans ce travail, nous avons examiné l'influence de facteurs cellulaires sur l'efficacité de translocation des toxines. L'utilisation d'un système rapporteur fluorescent CCF2/β-lactamase a permis de visualiser l'injection de toxine. En parallèle, l'association des protéines du translocon avec la membrane de la cellule hôte a été évaluée par immunodétection de PopB/D après fractionnement des membranes sur gradient de sucrose. Les cellules promyelocytaires HL-60 et promonocytaires U937 sont résistantes à l'injection de toxine, bien que PopB et PopD soient associées à la membrane. Après différenciation en neutrophiles, or monocytes/macrophages, ces cellules deviennent sensibles à l'injection sans que l'on détecte de variation notable de la quantité de protéines du translocon insérées dans la membrane. Le traitement des cellules HL-60 sensibles avec un agent déplétant le cholestérol, entraine une diminution de l'injection de toxine. De plus, la protéine PopB est retrouvée dans la fraction membranaire, obtenue par purification sur gradient de sucrose, contenant le marqueur des radeaux lipidiques flotilline. Par une approche pharmacologique, nous apportons la preuve que, en plus de la composition de la membrane, des voies de signalisation intracellulaires impliquées dans la polymérisation de l'actine sont essentielles pour la formation d'un pore fonctionnel. / The pathogenesis of Pseudomonas aeruginosa (P.a) implies multiple virulence factors among which the type III secretion system (T3SS). This multiprotein complex is composed of a needle through which four exotoxins are exported. The protein PopB and PopD form an oligomeric structure (translocon) at the end of the needle that inserts into the host cell membrane and translocates the exotoxins into the cytoplasm. Synthesis and toxin secretion is induced on contact with eukaryotic cell. In this work, we examined the influence of host cell elements on exotoxin translocation efficiency. The delivery of T3SS toxins was investigated using a CCF2/β-lactamase fluorescent reporter system In parallel, the association of translocon proteins with host plasma membranes was evaluated by immunodetection of PopB/D following sucrose gradient fractionation of membranes. Promyelocytic HL-60 cells and promonocytic U937 cells were found to be resistant to toxin injection even though PopB/D associated with host cell plasma membranes. Differentiation of these cells to neutrophil- or macrophage-like cells resulted in an injection-sensitive phenotype without any significant change in the level of membrane-inserted translocon proteins. Treatment of sensitive HL-60 cells with a cholesterol-depleting agent, resulted in a diminished injection of toxin. Moreover, the PopB translocator was found in the membrane fraction obtained from sucrose-gradient purifications and containing lipid-raft marker flotillin. Through a pharmacological approach, we brought evidence that, in addition to membrane composition, some general signalling pathways involved in actin polymerization may be critical for the formation of a functional pore.
475

A role for mammalian male accessory sex glands (ASG) secretions on epigenetic regulation of reproduction. / CUHK electronic theses & dissertations collection

January 2004 (has links)
Chan Oi Chi. / "May 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 259-310) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
476

Determinação do dia do parto de éguas e relação materno-filial / Determination of the day of parturient and mare and foal bond

Pereira, Yasmin de Sales 16 November 2017 (has links)
A presente dissertação foi elaborada em dois experimentos. No primeiro experimento objetivou-se determinar o dia do parto através de alterações físicas e circulatórias locais, e avaliar o pH da secreção da glândula mamária comparando dois métodos em éguas no pré-parto. Foram utilizadas 30 éguas gestantes sem raça definida (SRD), durante duas estações de monta (2015 e 2016), com idade de 10&#177;4 anos, e peso corporal de 560&#177;57 kg. Foram observadas possíveis alterações na área pélvica, abdominal, edema vulvar e a coloração da mucosa vaginal até o dia do parto através de fotográfias sequênciais, e as fotos foram analisadas individualmente e classificadas usando um sistema de escore. Para mensuração do pH, foi utilizado o peagâmetro portátil (Quimis&reg;) e o teste de pH em fita (Fusion&reg;). As colheitas iniciaram a partir de 310 dias de gestação. Para às mensurações do pH, foi utilizado um modelo misto sendo a égua o efeito aleatório e o tempo como efeito fixo. As associações entre as diferentes mensurações de pH foram avaliadas por meio de correlação de Momento-produto de Pearson. Para avaliar o escores físicos e circulatórios locais os dados foram analisados pelo teste de razão de Probabilidade Qui-Quadrado e por regressão, para observar a frequência dos escores 1, 2 ou 3 até o dia do parto. O nível de significância utilizado foi de 5%. O pH da secreção mamária pode ser utilizada para determinar o dia do parto, independente do método utilizado. A coloração de mucosa vaginal e edema vulvar podem auxiliar na predição do dia do parto, porém não devem ser utilizados como único método. No segundo experimento, o objetivo foi estudar o relacionamento entre a égua e e sua cria no primeiro dia pós-parto, e relacionar o fator progênitor sobre o comportamento do potro. Foram utilizadas 22 éguas multíparas e seus respectivos potros em duas temporadas de parto (2015 e 2016). Os progenitores eram formados por jumento e equinos. O etograma foi delineado considerando-se os comportamentos característicos apresentados por éguas e potros, e divididos em atividades de interação entre égua e produto, atividades do produto, postura e outros comportamentos. As observações foram realizadas no primeiro dia pós-parto durante 10 horas a cada 2 minutos, através de observação direta com rota de amostragem focal da égua e sua cria. Foi realizada a análise de frequência dos comportamentos ao longo do tempo, considerando cada par (égua/potro) como uma unidade experimental. As frequências dos comportamentos de interação, postura e outros comportamentos das éguas foram analisadas pelo teste de Qui-Quadrado para proporções iguais. Para dependência do comportamento do potro sobre o tipo de progênitor foi realizado o teste de Qui-Quadrado de Pearson. O nível de significância utilizado foi 5%. Concluí-se que no primeiro dia pós-parto as éguas buscam auxiliar a mamada, enquanto os potros mamam e descansam. Potros e muares apresentam diferenças na postura. / The present dissertation was elaborated in two experiments. The first experiment aimed to determine the day of birth through local physical and circulatory changes, and to evaluate the pH of the mammary gland secretion comparing two methods of mares in preparturient. Thirty non-defined pregnant mares (SRD) were used during two mating seasons (2015 and 2016), aged 10 &#177; 4 years, and body weight of 560 &#177; 57 kg. Possible alterations in pelvic, abdominal, vulvar edema and vaginal mucosa staining until the day of delivery were observed through sequential photographies, and the photos were analyzed individually and classified using a scoring system. For pH measurement, the portable pHmeter (Quimis&reg;) and the pH strip test (Fusion&reg;) were used. Crops started at 310 days of gestation. For the pH measurements, a mixed model was used, the mare being the random effect and the time as a fixed effect. The associations between the different pH measurements were evaluated through Pearson\'s Moment-product correlation. In order to evaluate the local physical and circulatory scores, the data were analyzed by the chi-square probability and regression test to observe the frequency of scores 1, 2 or 3 until the day of delivery. The level of significance was 5%. The pH of the mammary secretion can be used to determine the day of delivery, regardless of the method used. The coloration of vaginal mucosa and vulvar edema may aid in the prediction of the day of delivery, but should not be used as the sole method. In the second experiment, the objective was to study the relationship between the mare and her offspring on the first postpartum day, and to relate the progenitor factor to the foal behavior. Twenty - two multiparous mares and their respective foals were used in two calving seasons (2015 and 2016). The parents were formed by donkeys and horses. The etogram was delineated considering the characteristic behaviors presented by mares and foals, and divided into activities of interaction between mare and product, product activities, posture and other behaviors. The observations were performed on the first day postpartum for 10 hours every 2 minutes, through direct observation with the focal sampling route of the mare and her offspring. The behavioral frequency analysis was performed over time, considering each pair (mare / foal) as an experimental unit. The frequencies of the interaction behaviors, posture and other behaviors of the mares were analyzed by the Chi-square test for equal proportions. For the dependence of the behavior of the foal on the type of progenitor was carried out the test of Chi-Square of Pearson. The level of significance was 5%. It was concluded that on the first day postpartum the mares seek to assist the feeding, while the foals suck and rest. Foals and mules show differences in posture.
477

Proteínas envolvidas na secreção microapócrina na lagarta de Spodoptera frugiperda (Lepidoptera) / Proteins involved in microapocrine secretion in Spodoptera frugiperda caterpillar (Lepidoptera)

Silva, Walciane da 23 November 2012 (has links)
A região anterior do intestino médio de Lepidoptera apresenta uma secreção microapócrina de enzimas digestivas com vesículas migrando pelo interior das microvilosidades. Essas vesículas brotam das microvilosidades intestinais como vesículas de membrana dupla e são descarregadas dentro do lúmen. O objetivo desse trabalho foi identificar as proteínas secretadas e aquelas envolvidas na maquinaria secretória microapócrina em Spodoptera frugiperda. Para isso, vesículas microapócrinas foram preparadas e usadas para a produção de anticorpo policlonal. Esse anticorpo foi utilizado para varrer uma biblioteca de expressão de cDNA do intestino médio de S. frugiperda. Também obtivemos um transcriptoma por pirosequenciamento de uma biblioteca de cDNA proveniente dos transcritos do intestino médio do mesmo inseto. Os clones positivos da varredura foram sequenciados, montados e submetidos a um BLASTN contra as sequências obtidas pelo pirosequenciamento, o que resultou na extensão dessas sequências. Usamos ainda as sequências geradas pelo pirosequenciamento para reanalisar sequências de proteínas presentes nas membranas microvilares, que tinham sido obtidas anteriormente em nosso laboratório (Ferreira et al., 2007). A reanálise das sequências de proteínas microvilares gerou 66 proteínas preditas. Dessas, 18 foram consideradas contaminantes de outros compartimentos celulares e 48 associadas às membranas microvilares. A análise das sequências obtidas das vesículas microapócrinas gerou 50 proteínas preditas que podem ser secretadas por essa rota. As sequências encontradas tanto em membrana microvilar quanto em vesículas microapócrinas podem ser classificadas em 8 grupos, de acordo com sua função: (1) enzimas digestivas; (2) proteínas da membrana peritrófica; (3) envolvidas com proteção; (4) transportadores; (5) receptores; (6) proteínas da maquinaria secretória; (7) proteínas de citoesqueleto; (8) com função desconhecida nesse local. Em ambas as preparações existem uma predominância de sequências de enzimas digestivas. Nas membranas microvilares a maioria das sequências são aminopeptidases, enquanto nas vesículas microapócrinas a maioria são lipases. Os cDNAs correspondentes as proteínas que poderiam estar envolvidas na maquinaria secretória foram clonados e sequenciados. São elas: fimbrina, cofilina, gelsolina-1 e miosina I. RT-PCRs semi-quantitativas dessas proteínas em diferentes tecidos do inseto (intestino, túbulos de Malpighi, corpo gorduroso e carcaça) mostraram que somente gelsolina-1 está presente exclusivamente no intestino. Os domínios G1-G3 da gelsolina característica do intestino (gelsolina-1) foram expressos e usados para produzir anticorpos em coelhos. Esses anticorpos reconhecem a proteína recombinante e uma proteína presente no epitélio intestinal com massa molecular compatível com a massa predita para gelsolina-1. Foi possível diminuir a expressão de gelsolina-1 utilizando RNA interferente. / Lepidoptera anterior midgut presents a microapocrine secretion of digestive enzymes with secretory vesicles migrating inside the microvilli. These vesicles bud from the midgut microvilli as double membrane vesicles and are discharged into the lumen. The aim of this work was to identify the proteins secreted and those involved in the microapocrine secretory machinery in Spodoptera frugiperda larvae. For this, microapocrine vesicles were prepared and used for polyclonal antibody production. This antibody was used to screen a cDNA expression library of S. frugiperda midgut. We also obtained a transcriptome by pyrosequencing a cDNA library derived from transcripts of the midgut. Positive clones from the screening were sequenced, assembled and N-blasted against S. frugiperda sequences obtained by pyrosequencing. This procedure led to the extension of the sequences previously obtained. We also used the sequences generated by pyrosequencing to reanalyze the sequences of microvillar membrane proteins obtained previously by Ferreira et al. (2007). This reanalysis generated 66 predicted proteins that are present in the microvillar membranes. Eighteen were considered to be contaminants from other compartments and 48 associated with the microvillar membranes. Analysing the sequences from microapocrine vesicles we found 50 predicted proteins that should be secreted by microapocrine vesicles. The sequences found in both microvillar membrane and microapocrine vesicles may be classified into 8 groups, according to their function: (1) digestive enzymes; (2) peritrophic membrane proteins; (3) protection; (4) transporters; (5) receptors; (6) secretory machinery; (7) cytoskeleton; (8) with unknown function. In both preparations there is a predominance of sequences of digestive enzymes. In microvillar membranes, there is a remarkable amount of aminopeptidases, while in microapocrine vesicles this is true for lipases. cDNAs coding for proteins that could be involved in the microapocrine secretory machinery were cloned and sequenced. They are: fimbrin, cofilin, gelsolin-1 and myosin I. Using RT-PCR, we showed that mRNAs coding for gelsolin-1 and myosin I are present only in the intestinal tissue. The mRNAs coding for other proteins were found in all tissues. The domains G1-G3 from gelsolin specific from intestinal midgut (gelsolin 1) were expressed and used to raise antibodies in rabbit. These antibodies were able to recognize the recombinant protein and a protein from the midgut epithelium that has a molecular weight similar to the one predicted from gelsolin-1 sequence. We succeed in decreasing the expression of gelsolin-1 by using interfering RNA
478

Efeitos do uso de glicocorticoides sobre o metabolismo da glicose em ratos: estudo comparativo entre dexametasona e prednisona / EFFECTS OF USING GLICOCORTICOIDES ON THE METABOLISM OF GLUCOSE IN RATS: A COMPARATIVE STUDY BETWEEN DEXAMETHASONE AND PREDNISONE

Melo, Danylo Noleto de Sousa 29 September 2016 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-14T17:35:19Z No. of bitstreams: 1 DanyloMelo.pdf: 745489 bytes, checksum: c5ad51adb0decdb7d8050bcf5074660b (MD5) / Made available in DSpace on 2017-06-14T17:35:19Z (GMT). No. of bitstreams: 1 DanyloMelo.pdf: 745489 bytes, checksum: c5ad51adb0decdb7d8050bcf5074660b (MD5) Previous issue date: 2016-09-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / Synthetic glucocorticoids (GCs) induce several adverse effects when administered in high doses and/or prolonged, as peripheral insulin resistance, glucose intolerance, and alterations in lipid metabolism, especially hypertriglyceridemia. There are few studies on the metabolic impact caused by long-term treatments with different synthetic GCs, especially with prednisone, GC of intermediate action and first choice in its pharmacologic class. Therefore, we seek to verify the metabolic alterations caused by sub chronic treatment with prednisone in rats and compare them with existing and in acute model of insulin resistance induced by dexamethasone effects. For this, Wistar rats with of 90 days were treated with dexamethasone (D5) (1 mg/kg, i.p.) for 5 consecutive days and, its controls (C5) with saline, and Wistar rats of 60 days old were treated with prednisone (80 mg/kg, orally) for 15 days (P15) and 30 days (P30) consecutive and their respective controls (C15 and C30), received vehicle solution. The D5 results a decreased body weight (12.3%) and lower weight of retroperitoneal fat (38%), increased serum fasting glucose (12%) and fed (30%), insulin (80%) and triglycerides (339%) (p <0.05). Total fat and triglycerides liver were 29% and 52% higher in rats D5, compared to the C5 rats (p <0.05). The P15 rats had increased weight 61% less, reduction of retroperitoneal fat (29%) and increased plasma triglyceride concentrations (60%) compared to the C15 rats (p <0.05). As long as P30 rats had increased weight 44% less, reduction of retroperitoneal fat (25%) and increased serum triglycerides (78%) and liver total fat (26%) compared to the C30 rats (p <0,05). In vivo tests revealed the presence of impaired glucose tolerance (oGTT) in rats D5 and P30, and reduced insulin sensitivity (ipITT, HOMA, TYG) in D5 animals (p <0.05). Ex vivo test showed greater sensitivity in the pancreatic islets front glucose only in D5 rats. In conclusion, the sub chronic administration of prednisone promoted finer metabolic changes in glucose homeostasis, compared to acute administration of dexamethasone, suggesting the preferential use of prednisone when it is intended to minimize the adverse metabolic effects associated with the use of GCs. / Os glicocorticoides (GCs) sintéticos podem induzir diversos efeitos adversos, quando administrados em doses elevadas e/ou por tempo prolongado, como resistência insulínica periférica, intolerância à glicose, e alterações no metabolismo lipídico, especialmente hipertrigliceridemia. Porém existem poucos estudos sobre o impacto metabólico promovido por tratamentos prolongados com diferentes GCs sintéticos, especialmente com a prednisona, GC de ação intermediária e de primeira escolha em sua classe farmacológica. Diante disso, buscou-se verificar as alterações metabólicas ocasionadas pelo tratamento subcrônico com prednisona em ratos e compará-las aos efeitos presentes e conhecidos em modelo agudo de indução de resistência insulínica pela dexametasona. Para tal, ratos Wistar com noventa dias de vida foram tratados com dexametasona (D5) (1 mg/Kg, i.p.) durante 5 dias consecutivos e, os seus controles (C5) com salina, e ratos Wistar com 60 dias de vida foram tratados com prednisona (80 mg/Kg, v.o.) durante 15 dias (P15) e 30 dias (P30) consecutivos e, os seus respectivos controles (C15 e C30), receberam veículo. Os ratos D5 apresentaram redução do peso corpóreo (12,3%) e menor peso da gordura retroperitoneal (38%), aumento das concentrações séricas de glicose em jejum (12%) e alimentado (30%), insulina (80%) e triglicerídeos (339%) (p<0,05). O conteúdo de gordura total hepático, bem como triglicerídeos foram 29% e 52% maiores nos ratos D5, em relação aos ratos C5 (p<0,05). Os ratos P15 apresentaram um ganho de peso 61% menor, redução da gordura retroperitoneal (29%) e aumento nas concentrações plasmáticas de triglicerídeos (60%), em relação aos ratos C15 (p<0,05). Enquanto os ratos P30 apresentaram um ganho de peso 44% menor, redução da gordura retroperitoneal (25%) e aumento nas concentrações séricas de triglicerídeos (78%) e gordura total hepática (26%), em relação aos ratos C30 (p<0,05). Os testes in vivo revelaram a presença de intolerância à glicose (GTT) nos ratos D5 e P30 e redução da sensibilidade à insulina (ITT, HOMA, TyG) nos animais D5 (p<0,05). O teste ex vivo revelou maior sensibilidade nas ilhotas pancreáticas frente à glicose somente nos ratos D5. Em conclusão, a administração subcrônica de prednisona promoveu alterações metabólicas mais sutis na homeostasia da glicose, quando comparada à administração aguda de dexametasona, sugerindo assim, o uso preferencial da prednisona quando se pretende minimização dos efeitos adversos metabólicos associados ao uso de GCs.
479

Estudo preliminar da secre??o cut?nea em Aparasphenodon (Lophiohylinae, Anura): composi??o bioqu?mica e potencial t?xico / Preliminary study of skin secretion in Aparasphenodon (Lophiohylinae, Anura): biochemical composition and toxic potential

MONKEN, Francine Fran?a 30 September 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-31T19:17:42Z No. of bitstreams: 1 2016 - Francine Fran?a Monken.pdf: 2589456 bytes, checksum: 06c9e0d64d97d48b268dfd24bee047a6 (MD5) / Made available in DSpace on 2017-08-31T19:17:42Z (GMT). No. of bitstreams: 1 2016 - Francine Fran?a Monken.pdf: 2589456 bytes, checksum: 06c9e0d64d97d48b268dfd24bee047a6 (MD5) Previous issue date: 2016-09-30 / CAPES / This study aimed determinate the chemical composition of raw secretions expelled by two species of Aparasphenodon genus from compounds isolation, purification and structural identification. For this, individuals of A. brunoi (n=5) e A. arapapa (n=3) were collected in Ilha da Marambaia, municipality of Mangaratiba (RJ), and in municipality of Ilh?us (BA), respectively. The secretions were obtained by smooth electric stimulus and were translucent and little viscous, with approximated yield of 4 mg of sample/individual. For each species, was realized chromatography of thin layer, the revelator reagent ninhydrin indicated presence of amine groups after violet color appearing. Samples than were submitted with the same retention time (0.88 and 1.44 min) in both analysis, indicating presence of similar compounds in both species. In same way, samples purification realized by semi preparative liquid chromatography of high efficiency presented the same fractions number for both species. The structural determination was made by LC-MS/MS only for A. brunoi and reveled high collagen incidence and other uncharacterized proteins. Biological assays were realized in concentrations of 1?g.mL-1 and 10?g.mL-1 for both species. The assay of cellular viability did not present survival reduction of yeast, such as dosing of lipid peroxidation that did not show reaction with malonaldehyde in all tested cases. In other hand, the assay of mitochondrial damage reveled toxicity in concentration of 10 ?g.mL-1, reducing for discreet form the cellular viability in both samples. We conclude that both species have proteins as the main compound and, in a cellular level, are not harmful in 1 ?g.mL-1, but can promote damage in 10 ?g.mL-1. Besides that, as reveled profiles to both extracts, both chemical and biological assays were very close, the existence of a pattern in chemical composition of cutaneous secretions in amphibians of the same genus can be reinforced, even that species be in distinct environmental conditions. / O presente estudo buscou determinar a composi??o qu?mica das secre??es brutas expelidas por duas esp?cies de Aparasphenodon, a partir do isolamento, purifica??o e identifica??o estrutural destes compostos. Para tal, indiv?duos de A.brunoi (n=5) e A.arapapa (n=3) foram coletados na Ilha da Marambaia, Mangaratiba (RJ) e no munic?pio de Ilh?us (BA), respectivamente. As secre??es foram obtidas por est?mulo el?trico suave e mostraram-se translucidas e pouco viscosas, com rendimento aproximado de 4 mg de amostra/indiv?duo. Para cada esp?cie, foi realizada cromatografia em camada delgada; o reagente revelador ninidrina indicou presen?a de grupos am?nicos ap?s aparecimento da cor violeta. As amostras foram ent?o submetidas ? cromatografia liquida de alta efici?ncia anal?tica, sendo detectados dois picos majorit?rios com mesmo tempo de reten??o (0,88 e 1,44 min) em ambas as an?lises, indicando assim a presen?a de compostos semelhantes nas duas esp?cies. Da mesma forma, a purifica??o das amostras realizada por cromatografia liquida de alta efici?ncia semi-preparativa apresentou o mesmo n?mero de fra??es para ambas as esp?cies. A determina??o estrutural foi determinada por LC-MS/MS apenas para A. brunoi e revelou alta incid?ncia de col?geno e outras prote?nas n?o caracterizadas. Os ensaios biol?gicos foram realizados nas concentra??es de 1 ?g.mL-1 e 10 ?g.mL-1 para ambas as esp?cies. O ensaio de viabilidade celular n?o apresentou redu??o da sobreviv?ncia das leveduras, assim como a dosagem de peroxida??o lip?dica n?o mostrou rea??o com malonalde?do, em todos os casos testados. Por outro lado, o ensaio de dano mitocondrial revelou toxicidade na concentra??o de 10 ?g.mL-1, reduzindo de forma discreta a viabilidade celular, em ambas as amostras. Conclu?mos ent?o que as duas esp?cies possuem prote?nas como seu principal componente e, a n?vel celular, n?o s?o nocivas em 1 ?g.mL-1, mas podem promover danos quando em 10 ?g.mL-1. Al?m disso, como os perfis revelados para ambos os extratos, tanto nos ensaios qu?micos como nos biol?gicos, foram muito pr?ximos, a exist?ncia de um padr?o na composi??o qu?mica das secre??es cut?neas em anf?bios de um mesmo g?nero pode ser refor?ada, ainda que as esp?cies se encontrem em condi??es ambientais distintas.
480

Association study of transcription factors regulating insulin secretion and action in type 2 diabetes in Chinese.

January 2008 (has links)
Ho Sin Ka Janice. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 105-119). / Abstracts in English and Chinese. / Chapter CHAPTER 1. --- Introduction / Chapter 1.1. --- Epidemiology of Type 2 Diabetes --- p.1 / Chapter 1.2. --- Risk factors contributing to Type 2 Diabetes --- p.3 / Chapter 1.2.1. --- Environmental and physiological factors --- p.3 / Chapter 1.2.2. --- Genetic factors --- p.3 / Chapter 1.3. --- Disruption of energy homeostasis in the pathogenesis of type 2 diabetes --- p.6 / Chapter 1.3.1. --- Clinical spectrum of diabetes --- p.6 / Chapter 1.3.2. --- Insulin as a key regulator of energy homeostasis --- p.7 / Chapter 1.3.3. --- Insulin secretion and glucose metabolism --- p.8 / Chapter 1.3.4. --- Insulin action and lipid metabolism --- p.9 / Chapter 1.3.5. --- Lipotoxicity and glucotoxicity --- p.12 / Chapter 1.3.6. --- Role of transcription factors as metabolic switch --- p.13 / Chapter 1.4. --- Candidate genes implicated in type 2 diabetes susceptibility --- p.15 / Chapter 1.4.1. --- Candidate genes involved in insulin secretion pathway --- p.15 / Chapter 1.4.1.1. --- HNF4A --- p.15 / Chapter 1.4.1.2. --- HNF1A --- p.16 / Chapter 1.4.1.3. --- PDX1/PBX1 --- p.17 / Chapter 1.4.1.4. --- NEUROD1 --- p.17 / Chapter 1.4.1.5. --- GCK --- p.17 / Chapter 1.4.1.6. --- KCNJ11/ABCC8 --- p.18 / Chapter 1.4.2 --- Candidate genes involved in insulin action pathway --- p.19 / Chapter 1.4.2.1. --- PPARG --- p.19 / Chapter 1.4.2.2. --- PPARA --- p.20 / Chapter 1.4.2.3. --- PPARGC1A --- p.20 / Chapter 1.4.2.4. --- ADIP0Q --- p.21 / Chapter 1.4.2.5. --- LPL --- p.21 / Chapter 1.4.2.6. --- UPC --- p.22 / Chapter 1.5. --- Hypothesis and objectives of the study --- p.23 / Chapter CHAPTER 2. --- Materials and methods / Chapter 2.1. --- Study design --- p.25 / Chapter 2.1.1. --- Two-stage candidate gene association design --- p.25 / Chapter 2.1.2. --- Power calculation --- p.27 / Chapter 2.2. --- Study cohort --- p.29 / Chapter 2.2.1. --- Subject recruitment --- p.29 / Chapter 2.2.2. --- Clinical and biochemical measurements --- p.30 / Chapter 2.2.3. --- Clinical definitions --- p.31 / Chapter 2.3. --- Genetic study --- p.32 / Chapter 2.3.1. --- Candidate gene selection --- p.32 / Chapter 2.3.2. --- SNP selection --- p.32 / Chapter 2.3.3. --- DNA sample preparation --- p.35 / Chapter 2.3.4. --- Genotyping methods --- p.36 / Chapter 2.3.4.1. --- Allele specific Tm shift assay --- p.36 / Chapter 2.3.4.2. --- Mass spectrometry assay --- p.40 / Chapter 2.4. --- Data quality control --- p.42 / Chapter 2.4.1. --- Stage 1 --- p.42 / Chapter 2.4.2. --- Stage 2 --- p.42 / Chapter 2.5. --- Statistical analysis --- p.45 / Chapter 2.5.1. --- Stage 1 analysis --- p.45 / Chapter 2.5.2. --- Stage 2 analysis --- p.45 / Chapter 2.5.3. --- Stage 1 and 2 combined analysis --- p.46 / Chapter CHAPTER 3. --- Results / Chapter 3.1. --- Clinical characteristics of subjects in stages 1 and 2 studies --- p.48 / Chapter 3.2. --- Case-control associations in stage 1 --- p.51 / Chapter 3.2.1. --- Association with T2D --- p.51 / Chapter 3.2.2. --- Association with T2D subset by metabolic syndrome --- p.54 / Chapter 3.3. --- Case-control associations in stage 2 --- p.60 / Chapter 3.3.1. --- SNP selection for genotyping --- p.60 / Chapter 3.3.2. --- Association with T2D --- p.63 / Chapter 3.3.3. --- Association with T2D subset by metabolic syndrome --- p.64 / Chapter 3.4. --- Case-control associations in combined stages 1 and 2 --- p.66 / Chapter 3.4.1. --- Association with T2D --- p.66 / Chapter 3.4.2. --- Association with T2D subset by metabolic syndrome --- p.70 / Chapter 3.4.3. --- Association with T2D subset by age at diagnosis --- p.74 / Chapter 3.4.4. --- Association with T2D subset by gender --- p.76 / Chapter 3.4.5. --- Genetic epistasis for T2D association --- p.79 / Chapter 3.5. --- Metabolic traits associations in control subjects in combined stages 1 and 2 studies --- p.83 / Chapter CHAPTER 4. --- Discussion --- p.86 / Chapter 4.1. --- Role of insulin secretion genes in type 2 diabetes --- p.87 / Chapter 4.2. --- Role of insulin action genes in type 2 diabetes --- p.92 / Chapter 4.3. --- Combined genetic effects on risk for type 2 diabetes --- p.97 / Chapter 4.4. --- Summary --- p.98 / Chapter 4.5. --- Limitation of this study and future direction --- p.101 / REFERENCES --- p.104 / APPENDICES --- p.119 / Chapter Appendix 1: --- Gene structure and linkage disequilibrium of genotyped SNPs of candidate genes --- p.119 / Chapter Appendix 2: --- Information of SNPs genotyped in stage 1 --- p.130 / Chapter Appendix 3: --- T2D association results (additive model) of 152 SNPs for stage 1 case- control samples --- p.137 / Chapter Appendix 4: --- T2D association results (additive model) of 152 SNPs for stage 1 case- control samples subset by metabolic syndrome status in cases --- p.144 / Chapter Appendix 5: --- T2D association results (additive model) of 22 SNPs for stage 2 case- control samples --- p.151 / Chapter Appendix 6: --- T2D association results (additive model) of 22 SNPs for stage 2 case- control samples subset by metabolic syndrome status in cases --- p.153

Page generated in 0.0615 seconds