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Sobrevida e fatores que influenciam a morbi-mortalidade na terapêutica cirúrgica e adjuvante do adenocarcinoma da junção esôfago-gástrica / Survival and morbidity-mortality factors in the surgical and adjuvant treatment of the adenocarcinoma of esophagogastric junctionTercioti Junior, Valdir, 1975- 05 February 2013 (has links)
Orientadores: Nelson Adami Andreollo, Luiz Roberto Lopes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-22T11:50:25Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: Nos últimos anos a literatura médica tem registrado aumento progressivo da prevalência do adenocarcinoma da junção esôfago-gástrica. O tratamento cirúrgico é a melhor opção, entretanto, vários fatores podem interferir na morbimortalidade. O objetivo do presente estudo é avaliar retrospectivamente a sobrevida e os fatores prognósticos dos pacientes operados por adenocarcinoma da junção esôfago-gástrica submetidos ou não a radioterapia e quimioterapia adjuvantes. Foram revistos os prontuários médicos dos pacientes tratados no Hospital de Clínicas da Universidade Estadual de Campinas no período de 1986 a 2009, para obtenção de informações referentes ao pré e pós-operatório. Assim, os pacientes foram divididos: a) um grupo submetido a tratamento cirúrgico exclusivo; e b) um grupo submetido a cirurgia seguida por radioterapia e quimioterapia adjuvantes. Foram analisados os fatores de morbimortalidade e da sobrevida entre os grupos. Análises de regressão univariada e multivariada de Cox dos fatores de risco para o prognóstico destes pacientes foram realizadas. O nível de significância estatística adotado foi de 5 %. No estudo foram incluídos 103 (N) pacientes assim distribuídos: 1) 78 (75,7%) submetidos a tratamento cirúrgico exclusivo e 2) 25 (24,3%) submetidos a tratamento cirúrgico com radioquimioterapia adjuvante. Todos os pacientes foram submetidos a ressecção cirúrgica com intenção curativa. xxvi Os grupos foram comparáveis quanto a cor, sexo, idade, procedência, classificação de Siewert, tipo histológico, T patológico, N patológico, estadiamento patológico, recidiva tumoral, sintomas pré-operatórios (exceto dor retroesternal), complicações pós-operatórias, técnica de ressecção cirúrgica e técnica de reconstrução do trânsito alimentar. Os resultados mostraram que os grupos foram diferentes quanto ao grau de diferenciação tumoral e ao número de linfonodos. O estudo não mostrou aumento da sobrevida no grupo submetido a tratamento adjuvante em comparação ao grupo submetido a tratamento cirúrgico exclusivo. A análise multivariada de regressão de Cox de toda a casuística concluiu que a recidiva tumoral, a presença de metástase linfonodal e a presença de broncopneumonia no pós-operatório foram fatores de piora no prognóstico / Abstract: In recent years the medical literature has reported a progressive increase in the prevalence of adenocarcinoma of the esophagogastric junction. Surgical treatment is the best option, however, several factors can affect the morbidity and mortality. The aim of this study is to evaluate retrospectively survival and prognosis of patients operated for adenocarcinoma of the esophagogastric junction, undergoing or not postoperative radiotherapy and chemotherapy. We reviewed the medical records of patients treated at Hospital de Clinicas of State University of Campinas from 1986 to 2009, to obtain data about pre- and post-operative treatment. The patients were divided into: a) patients undergoing surgical treatment alone; and b) patients undergoing surgery followed by adjuvant radiotherapy and chemotherapy. We analysed morbidity, mortality and survival between groups. Univariate and multivariate Cox regression analyzes of risk factors for prognosis of these patients were performed. The level of significance was 5%. The study included 103 (N) patients as follows: 1) 78 (75.7%) undergo surgical treatment only; and 2) 25 (24.3%) underwent surgical and adjuvant treatment. All patients underwent surgical resection with curative intent. The groups were comparable in terms of color, sex, age, origin, Siewert classification, histological type, pathological T, pathological N, pathological stage, tumor recurrence, preoperative symptoms (except retrosternal pain), xxviii postoperative complications, technique of surgical resection and technique of reconstruction of the alimentary tract. The groups differed in the degree of tumor differentiation and the number of lymph nodes. The study did not show increase in survival in the group undergoing adjuvant treatment compared to the group treated with surgery alone. Multivariate Cox regression of the whole sample found that tumor recurrence, lymph node metastasis and the presence of postoperative pneumonia were factors worsened prognosis / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências
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Efeitos do veneno de Rhinella schneideri sobre a junção neuromuscular / Effects of Rhinella schneideri poison on neuromuscular junctionFerreira, Sandro Rostelato, 1982- 19 August 2018 (has links)
Orientador: Léa Rodrigues Simioni / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T21:13:03Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: Rhinella schneideri, conhecido previamente como Bufo paracnemis, é um sapo comum em muitas regiões do Brasil. O veneno destas espécies exerce importante efeito cardiovascular em humanos e animais, mas pouco se sabe sobre sua atividade neuromuscular. Neste trabalho, nós avaliamos a neurotoxicidade do veneno de R. schneideri em preparações neuromusculares de pintainho e camundongo. Através da compressão manual das glândulas parótidas localizadas atrás dos olhos, coletou-se a secreção e então realizada a extração com metanol. O extrato metanólico foi liofilizado e testado em preparações biológicas. Preparações biventer cervicis (BC) de pintainho e nervo frênico diafragma (NFD) de camundongo foram utilizadas para o registro miográfico através de estimulação elétrica indireta para medidas eletrofisiológicas, análise morfológica e microscopia eletrônica de transmissão. Frações ativas do extrato metanólico foram obtidas submetendo-se à coluna de fase reversa Luna PFP (250 x 4,6 mm). O extrato metanólico (50 ?g/ml) causou somente facilitação da neurotransmissão em preparações NFD. Ao contrário, causou bloqueio neuromuscular significativo em preparações BC que foram concentração-dependente (3, 10 and 30 ?g/ml; a 37º C) com tempo para 50% de bloqueio, média ± erro padrão: 84±10, 51±3 e 12±0,8 min com 3, 10 e 30 ?g/ml, respectivamente; n=6-8 cada, precedido por facilitação da neurotransmissão. Não houve inibição significativa das respostas contraturantes à ACh (110 ?M) ou KCl (20 mM) após bloqueio completo em qualquer concentração testada. Em preparações BC incubadas com o extrato metanólico (10 ?g/ml) a 22º C por 70 min não observou-se qualquer alteração das respostas musculares (117±3%; n=5), mas quando a temperatura do banho foi elevada a 37º C, 50% de bloqueio ocorreu após 92±3 min (n=5; p<0.05). A incubação de preparações BC curarizadas (d-Tc, 1 ?g/ml) com o extrato metanólico (10 ?g/ml) resultou em completo e irreversível bloqueio enquanto que as preparações tratadas somente com curare mostraram a reversão completa da resposta contrátil após várias lavagens. Não houve aumento significativo nos níveis de liberação de creatinoquinase (90±21 vs. 80±15 U/l, antes e após 120 min de incubação com o extrato, respectivamente, n=5) além da ausência de alterações na morfologia das fibras musculares ou na porcentagem de danos na fibra (2.4±0.9 vs. 2.3±0.5 %, antes e após 120 min de incubação com o extrato, respectivamente, n=5). O extrato metanólico (50 ?g/ml) aumentou a resposta contrátil mas não alterou o potencial de membrana em repouso (-81±1 mV e -78±1 mV para controle e preparação tratada após 60 min). Registros eletrofisiológicos mostraram que houve um aumento progressive na frequência dos potenciais de placa terminal em miniatura (PPTM) de 34±3,5 (controle) para 88±15 (após 60 min de incubação com o extrato); houve também um aumento nos valores do conteúdo quântico, de 128±13 (controle) para 272±34 e 171±11 após 5 min e 60 min, respectivamente, em preparações tratadas com o extrato metanólico. A microscopia eletrônica de transmissão mostrou que o volume ocupado pelas vesículas sinápticas foi significativamente reduzida (32±5%; p<0.05) após 5 min mas este efeito foi reversível após 60 min de incubação para as preparações tratadas com 50 ?g/ml do extrato metanólico. Não houve dano estrutural distinguível na membrana do terminal nervoso e nas mitocôndrias das preparações tratadas com o extrato, quando comparada com as preparações controle. O pré-tratamento das preparações NFD com ouabaína (1 ?g/ml), um inibidor da bomba de Na+/K+-ATPase, por 5 min antes da incubação com o extrato, preveniu o aumento do conteúdo quântico comparado com preparações controle (118±18, 117±18 e 154±33 para preparações controle-ouabaína e tratadas com ouabaína e incubadas com o extrato por 5 min e 60 min, respectivamente). A cromatografia por HPLC do extrato metanólico resultou em 24 frações, das quais 4 (frações 20, 21, 22 e 24) causaram bloqueio neuromuscular em preparações BC. A fração 20 (3 ?g/ml) foi escolhida por ser 3 vezes mais potente que as demais e causou bloqueio neuromuscular significativo (p<0.05; tempo para 50% de bloqueio: 43±4 min; n=4) precedido por facilitação em preparações BC a 37º C. A fração 20 não inibiu as respostas contraturantes à ACh (110 ?M) ou KCl (20 mM) após completo bloqueio neuromuscular em preparações BC. Em preparações NFD, a fração (15 ?g/ml) aumentou significativamente os valores do conteúdo quântico de 117±18 (controle) para 236±44 após 5 min de incubação (n=4; p<0.05). Estes resultados indicam que o extrato metanólico do veneno de R. schneideri é capaz de interferir com a neurotransmissão por ativar e/ou bloquear a liberação da acetilcolina nos sítios pré-sinápticos, provavelmente envolvendo a bomba de Na+-K+-ATPase, sem causar qualquer dano à musculatura / Abstract: Rhinella schneideri, previously known as Bufo paracnemis, is a common toad in many regions of Brazil. The venom of this species exerts important cardiovascular effects in humans and animals, but little is known of its neuromuscular activity. In this work, we examined the neurotoxicity of R. schneideri venom in chick and mouse neuromuscular preparations. Venom was collected by manual compression of the large parotid glands behind the eyes and then extracted with methanol. The extract was lyophilized prior to testing in biological preparations. Chick biventer cervicis (BC) and mouse phrenic nerve-diaphragm (PND) preparations were mounted for conventional twitch-tension recording in response to indirect stimulation, for electrophysiological measurements, morphological analysis and transmission electronic microscope. Also, an active fraction of this methanolic extract obtained by reverse phase HPLC on a Luna PFP (250 x 4.6 mm) column. The methanolic extract (50 ?g/ml) caused facilitation but no neuromuscular blockade in PND preparations. In contrast, significant (p<0.05) concentration-dependent (3, 10 and 30 ?g/ml) neuromuscular blockade (time for 50% blockade, mean±S.E.M.: 84±10, 51±3 and 12±0.8 min with 3, 10 and 30 ?g/ml, respectively; n=6-8 each) preceded by facilitation was seen in BC preparations at 37oC. There was no inhibition of contractures to exogenous ACh (110 ?M) or KCl (20 mM) after complete blockade by any of the concentrations tested. Incubation of BC preparations with methanolic extract (10 ?g/ml) at 22oC for 70 min did not affect neuromuscular transmission (117±3%; n=5), but when the bath temperature was increased to 37oC, 50% blockade occurred within 92±3 min (n=5; p<0.05). Incubation of curarized (d-Tc, 1 ?g/ml) BC preparations with methanolic extract (10 ?g/ml) resulted in complete, irreversible blockade whereas preparations treated with curare alone showed complete reversion in the twitch-tension after washing. There was no significant increase in creatine kinase levels (90±21 vs. 80±15 U/l, before and after a 120 min incubation with extract, respectively; n=5) and no significant alterations in muscle fiber morphology or in the percentage of damaged fibers (2.4±0.9 vs. 2.3±0.5 % before and after a 120 min incubation with extract, respectively; n=5). The methanolic extract (50 ?g/ml) increased the twitch-tension but did not alter the membrane resting potential (-81±1 mV and -78±1 mV for control and poison-treated preparations after 60 min). Electrophysiological measurements showed that there was a progressive increase in the frequency of miniature end-plate potentials (MEPPs) from 34±3.5 (control) to 88±15 (after a 60 min incubation with extract); there was also an increase in the end-plate potentials (based on the quantal content) from 128±13 (control) to 272±34 and 171±11 after 5 min and 60 min, respectively, in extract-treated preparations. TEM showed that the fractional volume occupied by synaptic vesicles was significantly reduced (32±5%; p<0.05) after a 5 min but this effect was reversible after 60 min of incubation to 50 ?g/ml of methanolic extract. There was no structural damage to the membrane of the terminal boutons and the mitochondria of extract-treated preparations were indistinguishable from those of control preparations. Pretreatment of the preparations with ouabain (1 ?g/ml), a Na+/K+-ATPase pump inhibitor, for 5 min prior to incubation with methanolic extract prevented the increase in quantal content compared to preparations without extract (118±18, 117±18 and 154±33 for ouabain-treated controls and ouabain-treated preparations incubated with venom for 5 min and 60 min, respectively). HPLC of the methanolic extract resulted in 24 fractions, of which four (fractions 20, 21, 22 and 24) produced blockade in BC preparations. Fraction 20 (3 ?g/mL) was chosen because was the most potent of the four fractions and caused significant (p<0.05) neuromuscular blockade (time for 50% blockade: 43±4 min; n=4; mean±SEM) preceded by facilitation in BC preparations at 37oC. Fraction 20 did not inhibit contractures to exogenous ACh (110 ?M) or KCl (20 mM) after complete neuromuscular blockade in BC preparations. In PND preparations, fraction 20 (15 ?g/mL) significantly increased the quantal content value from 117±18 (control) to 236±44 after 5 min (n=4; p<0.05). These results indicate that the methanolic extract of R. schneideri is capable to interfere with the neurotransmission by activing and/or blocking the pre-synaptic acetylcholine release by an activity involving the Na+-K+-ATPase pump, without damaging the muscle membrane / Doutorado / Farmacologia / Doutor em Farmacologia
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Características estruturais da junção osteotendínea do músculo tríceps sural de ratos Wistar adultos e idosos: estudo aos microscópicos de luz, microscópico eletrônico de varredura e de transmissão / Structural characteristics of the bone-tendon junction of triceps surae muscle of the adult and old Wistar rats: Light microscope, scanning electron microscope and transmission electron microscope studyDiego Pulzatto Cury 18 December 2013 (has links)
Os tendões são tecidos de transição das forças contráteis geradas pelos músculos e as transferindo para os ossos, podendo assim gerar movimento. A região em que o tecido tendíneo se insere ao ósseo é chamada de junção osteotendínea ou entese. Estas junções podem ser classificadas como fibrosas ou fibrocartilaginosas, as fibrosas são aquelas em que os tendões e/ou ligamentos se inserem no eixo (diáfise) dos ossos longos e as fibrocartilaginosas a inserção ocorre nas epífises dos ossos longos ou nos ossos curtos. Este estudo tem como propósito analisar as fibras colágenas e as células presentes na junção osteotendínea, utilizando microscopia de luz com as colorações de Hematoxilina-eosina, Azocarmim, Picro-sírius e Tricromo de Masson e os aspectos ultraestruturais empregando os métodos de microscopia eletrônica de varredura e de transmissão. Foram utilizados 30 ratos Wistar machos, sendo 15 adultos com idade de 4 meses (grupo A) e 15 idosos com idade de 18 meses (grupo B), sendo utilizados 5 ratos de cada grupo para microscopia de luz, 5 para microscopia eletrônica de varredura e 5 para microscopia eletrônica de transmissão. Os membros posteriores dos ratos foram retirados, dissecados e desmineralizados com EDTA a 7% para microscopia de luz e EDTA 0,15M pH 7,4 para microscopia eletrônica de transmissão durante 4 semanas, não foi necessário desmineralizar as amostras para microscopia eletrônica de varredura. Cortes de 6 m foram realizados e montados em lâminas histológicas para análise em microscópio de luz, a técnica de criofratura em nitrogênio líquido foi realizada para análises em microscópio eletrônico de varredura e cortes de 60 nm foram realizados, montados em telas de cobre de 200 mesh (EMS) para análises em microscópio eletrônico de transmissão. O processo de envelhecimento mostrou alterações das fibrilas colágenas, em que o tipo I predomina no grupo adulto e o tipo III no idoso, diminuição na quantidade de células de fibrocartilagem, processos citoplasmáticos destas células curtos e em número reduzido e uma diminuída capacidade de síntese devido a aparelhos de Golgi menores, poucas cisternas de retículo endoplasmático granular e escassas mitocôndrias. / Tendons are transition tissues of contractile forces generated by muscles and transferring to bone, generating this way move. The region where tendon attach to bone is called bone-tendon junction or enthesis. These junctions can be classified as fibrous or fibrocartilaginous, the fibrous are those in which tendons/ligaments are attached in the shaft (diaphysis) of the long bones and fibrocartilaginous attachment occur in the epiphyses of the long bones or short bones. This study aims to analyze collagen fibers and the cells present in the bone-tendon junction, using light microscope with Hematoxylineosin, Azocarmine, Picrosirius red and Masson\'s trichrome staining and ultrastructural aspects using scanning electron microscope, transmission electron microscope methods. Thirty male Wistar rats were using, 15 adults rats at 4 months-old (A group) and 15 old rats at 18 months-old (B group), were used 5 rats of each group to light microscopy, 5 rats to scanning electron microscopy and 5 rats to transmission electron microscopy. The hind limbs of the rats were removed, dissected and demineralized using 7% EDTA solution to light microscopy and 0,15M pH 7,4 EDTA solution to transmission electron microscopy for 4 weeks, was not necessary demineralize the samples to scanning electron microscopy. Cut in slices 6 m thickness were made and mounted on histological slides to analyze in light microscope, freeze-fracture technique with liquid nitrogen was performed to analysis in scanning electron microscope and cuts in slices 60 nm thickness were made, mounted on copper grids (200-mesh - EMS) to analysis in transmission electron microscope. The aging process showed changes of the collagen fibrils, in which type I predominates on adult groups and the type III on the old group, decrease in the amount of the fibrocartilage cells, few and short cytoplasmic processes of this cells and a decreased synthesis capacity due a small Golgi apparatus, a few cisternae of rough endoplasmatic reticulum and few mitochondria.
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Experimental study of acute pancreatitis in a porcine model, especially tight junction structure and portal vein cytokinesMeriläinen, S. (Sanna) 05 February 2013 (has links)
Abstract
Acute pancreatitis is a common disease, Finland being among the countries with the highest incidence. The majority of patients have a mild, self-limiting disease. However, 20% of these patients develop severe necrotizing pancreatitis with a mortality rate of 7 to 25%. The mechanisms for developing the severe disease are not known, it is not possible to accurately forecast the severity of the disease and there is no curative treatment yet.
This study was aimed at analyzing the early phase of acute experimental porcine oedematous and necrotizing pancreatitis. In Study I, the pancreatic microcirculatory changes were measured and the expression of tight junction proteins (claudins-2, -3, -4, -5 and -7) and the rate of apoptosis in the pancreas were all measured. In Study II, bacterial translocation to the blood in the portal vein blood or to the mesenteric lymph nodes was analyzed and the intestinal expression of tight junction proteins (claudins-2, -3, -4, -5 and -7) and the intestinal apoptosis/ proliferation rates were measured. The basic histology of the jejunum and colon were analyzed. Study III analyzed which cytokines are released from the pancreas to the portal venous blood. In Study IV, the ultrastructure of the epithelium of the jejunum and colon was analyzed and the expression of adherens junction proteins, E-cadherin and β-catenin, were measured from both jejunum and colon.
The first study (I) showed that membranous immunoreactivity of claudin-2 in acinar cells appeared in the pancreas during acute oedematous and necrotizing pancreatitis. The expressions of claudins -3, - 4, - 5 and 7 were unaffected. The second study (II) showed that bacterial translocation from the gut was not present at the beginning of acute porcine pancreatitis. The expressions of claudins-2 and -5 do not become altered; however, there might be some decrease in claudin-3 expression in the colon and decrease in the expression of claudins-4 and -7 in the jejunum in necrotizing pancreatitis. Performing the laparotomy itself caused increased apoptosis in the colon and the jejunum. In the third study (III), the initial inflammatory process was diverse in oedematous and necrotizing pancreatitis. Increased monocyte count in combination with elevated PDGF and IL-6 are characteristic of necrotizing pancreatitis in our model. The fourth study (IV) indicated that necrotizing pancreatitis caused damage to the epithelial and endothelial cells of the colon in the early stages of the disease. The expression of E-cadherin immunoreactivity showed a decreasing trend in the colon in both oedematous and necrotizing pancreatitis.
The results of this study suggest that claudin-2 increases in acinar cells during acute porcine pancreatitis. Bacterial translocation is not present during the early phase of acute porcine pancreatitis. Increased monocyte count and elevated PDGF and IL-6 are characteristic of early phase necrotizing porcine pancreatitis and necrotizing porcine pancreatitis causes damage to the epithelial and endothelial cells of the colon. / Tiivistelmä
Akuutti haimatulehdus on yleinen sairaus, jonka ilmaantuvuus Suomessa on verrattain suuri. Suurimmalla osalla potilaista tauti on lievä ja itsestään paraneva. Kuitenkin 20 %:lle potilaista kehittyy vaikea haimatulehdus, johon liittyy 7–25 %:n kuolleisuus. On epäselvää, miksi toisinaan kehittyy vaikea tautimuoto. Taudin vaikeusastetta ei voida etukäteen tarkasti ennustaa, eikä tautiin ole parantavaa hoitoa.
Väitöskirjatyön tarkoituksena oli tutkia lievän ja vaikean haimatulehduksen varhaisvaihetta kokeellisessa sikamallissa. Työssä I mitattiin haiman mikroverenkierron muutoksia, tutkittiin tiivisliitosproteiinien klaudiini-2:n, -3:n, -4:n, -5:n ja -7:n ilmenemistä sekä apoptoosin määrää haimassa. Toisessa työssä tutkittiin mahdollista bakteeritranslokaatiota porttilaskimovereen ja vatsaontelon imusolmukkeisiin, mitattiin suoliston tiivis liitos-proteiinien klaudiinien-2, -3, -4, -5 ja -7 ilmenemistä ja suoliston apoptoosin ja soluproliferaation määrää. Mahdollisia muutoksia ohut- ja paksusuolen perushistologiassa analysoitiin. Kolmannessa työssä mitattiin sytokiinipitoisuuksia porttilaskimoverestä. Neljännessä työssä analysoitiin ohut- ja paksusuolen mikrorakennetta elektronimikroskopian avulla ja mitattiin vyöliitosproteiinien E-cadherin ja β-catenin määrää.
I työssä todettiin klaudiini-2:n ilmaantuvan haiman asinaarisolujen solukalvoille lievässä ja vaikeassa kokeellisessa haimatulehduksessa. Klaudiinien 3,- 4,- 5 ja 7 esiintyminen haimassa ei muuttunut. II työssä todettiin, että bakteeritranslokaatiota ei tapahtunut seuranta-aikana. Suolistossa klaudiinien-2 ja -5 ilmenemisessä ei tapahtunut muutoksia. Klaudiini-3:n ilmenemisessä paksusuolessa ja klaudiinien -4 ja -7 ilmenemisessä ohutsuolessa saattaa tapahtua vähenemistä vaikeassa haimatulehduksessa. Tutkimustoimenpide itsessään aiheutti ohut- ja paksusuolen apoptoosin lisääntymistä. III työn mukaan tulehdusvaste oli erilainen akuutissa lievässä ja vaikeassa kokeellisessa haimatulehduksessa. Monosyyttimäärän sekä PDGF:n ja IL-6:n pitoisuuksien lisääntyminen, olivat tyypillisiä vaikealle haimatulehdukselle tässä mallissa. IV työssä todettiin, että vaikea haimatulehdus vaurioittaa paksusuolen epiteeli- ja endoteelisoluja. E-cadherin: n määrässä todettiin jonkin verran vähentymistä sekä lievässä että vaikeassa haimatulehduksessa.
Näiden tulosten mukaan klaudiini-2 lisääntyy sian haiman asinaarisoluissa akuutissa haimatulehduksessa. Sialla ei tapahdu bakteerien translokaatiota haimatulehduksen varhaisvaiheessa. Sian vaikeaan haimatulehdukseen liittyy monosyyttien, PDGF:n ja IL-6:n lisääntyminen. Kokeellisessa vaikeassa haimatulehduksessa paksusuolen epiteeli- ja endoteelisolut vaurioituvat jo varhaisvaiheessa.
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Comparative DNA‐Protein Interaction and Epithelial Tight Junctions Modulation Potential of Immunosuppressive RegimeKhan, Niamat 14 January 2016 (has links)
No description available.
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Effects of beta-2 adrenergic receptor agonists in DOK7 congenital myasthenic syndromeClausen, Lisa January 2015 (has links)
Congenital myasthenic syndromes (CMS) are a rare group of heterogeneous disorders, characterised by compromised neuromuscular transmission and symptoms of fatiguable muscle weakness. CMS is caused by mutations in genes that affect the structure and function of the neuromuscular junction (NMJ). In about 20% of CMS cases, patients have mutations in the gene DOK7; the protein product, DOK7, is crucial for maintaining the dense aggregation of acetylcholine receptor (AChR) clusters at the NMJ. DOK7-CMS patients do not respond to treatment with acetylcholinesterase inhibitors which are the first line treatment for most forms of CMS. Instead, a dramatic response to beta-2 adrenergic receptor (ADRB2) agonists, such as salbutamol, is observed. The aim of this project was to investigate the molecular mechanisms that underlie the beneficial effects of ADRB2 agonists. Firstly, NMJ functioning was modelled in vitro by studying AChR clusters formed on cultured C2C12 mouse myotubes in the presence of WT DOK7. Overexpression of mutant DOK7 led to a significant reduction in the number of AChR clusters, explaining the pathogenic effect of the mutation. Importantly, incubation of myotubes with salbutamol increased the number of AChR clusters and their stability. The results provide the first evidence that ADRB2 agonists directly affect proteins located at the NMJ. However, this disease model suffers from limitations. The rest of the thesis focussed on developing alternative cell culture models to explore the AChR clustering pathway. The first model combined optogenetics and fluorescence lifetime microscopy to study the effects of ADRB2 activation on AChR cluster stability in single live cells. The second used CRISPR/Cas9 genome editing tools to directly introduce Dok7 mutations to the genome of C2C12 cells, thereby overcoming some of the drawbacks associated with DOK7 overexpression. Further manipulations of these novel model systems will be used in the future to examine in more detail the molecular events underlying the pathogenic effects of DOK7 mutations and the mechanisms of ADRB2 agonists.
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Fonctionnement des jonctions âmes-membrures en Béton Fibrés à Ultra-Hautes Performances (BFUP) / Behavior of web-flange junction in UHPFRC structuresHerrera, Amaury 20 June 2017 (has links)
Dans le cadre de l’utilisation de plus en plus courante des BFUP dans des structures techniquement ou architecturalement complexes et de la recherche d’optimisation de la quantité de matériau mis en œuvre, cette thèse s’intéresse au fonctionnement des jonctions en BFUP. Son objectif principal est de mettre en évidence les phénomènes physiques qui interviennent dans la jonction et de mieux les retranscrire dans les méthodes de calcul afin de mieux en maîtriser la sécurité et d’optimiser la matière mise en oeuvre.Le travail de thèse s’articule en quatre étapes :- Une étude bibliographique a permis d’établir les bases de connaissances permettant de dimensionner les campagnes expérimentales et de proposer une structure de modélisation des jonctions âme-membrure.- Le développement d’un modèle analytique avancé permettant de prédire le comportement d’une poutre en Té soumise à une sollicitation combinée de flexion longitudinale (et donc de cisaillement longitudinal dans la table) et de flexion transversale.- L’étude expérimentale, à l’échelle du matériau, du comportement des BFUP sous sollicitation de cisaillement pur. Cette étude permet d’enrichir les connaissances sur le comportement des BFUP (données encore indisponibles dans la carte d’identité des différents matériaux) et constitue également une donnée d’entrée pour la compréhension quantitative des phénomènes qui interviennent dans la jonction, à l’échelle de la structure, lorsqu’elle est sollicitée en cisaillement longitudinal.- Enfin, l’essai à rupture de 6 poutres en Té à l’échelle 1 a permis d’étudier le comportement expérimental des jonctions soumises à des sollicitations de cisaillement longitudinal. Les résultats expérimentaux de cette étude ont été comparés aux différentes prédictions analytiques possibles, y compris le modèle proposé.Ces travaux de thèse ont permis d’apporter de nouveaux outils de dimensionnement (notamment dans le cadre de l’étude de la résistance des jonctions en BFUP sous sollicitation de cisaillement pur). Ils mériteraient d’être complétés par des essais de poutres soumis à une sollicitation concomitante de flexion longitudinale et de flexion transversale, pour mieux conforter les méhodes d’analyse proposées / Ultra-high performance fiber-reinforced concrete (UHPFRC) are increasingly used for technically or architecturally complex structures and research is going on to optimize design and save implemented material quantities. In this context, this thesis focuses on the mechanical behavior of junctions in UHPFRC structures. The main goal is to highlight physical phenomena occurring in the junctions in order to optimally transpose them into calculation methods. In this way, both safety and cost-efficience should be better controlled.This thesis is divided in four steps :- A literature review enabled to establish the background knowledge allowing to design the experimental campaigns and to suggest a modeling for web-flange junctions.- An advanced analytical model was developed in order to predict the behavior of a T-beam subjected to combined longitudinal bending (and therefore longitudinal shear in the table) and transverse bending.- The expérimental study, at the material scale, of UHPFRC behavior under pure shear stress, allowed enriching the knowledge in this field (data still unavailable in the identity card of current UHPFRC mixes). It also constituted an input for the quantitative understanding of the phenomena occuring in the junction, at the structure scale, when it is loaded in longitudinal shear.- Finally, the test of 6 full scale T-beams up to failure made it possible to study the experimental behavior of the junctions subjected to longitudinal shear stresses. The experimental results were compared with the various analytical predictions, including the proposed model.A new approch has thus been proposed to design junctions under longitudinal shear. It should be completed with experiments on T-beams under combined longitudinal and transverse bending to further validate the proposed analysis methods
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Analyse physique et simulations numériques avancées des écoulements de jonction sur les avions / Physical analysis and advanced numerical simulations of junction flowsBordji, Mehdi Mokhtar Paul 09 October 2015 (has links)
Le décollement de coin est un phénomène pouvant apparaître sur les avions au niveau par exemple de la jonction voilure/fuselage. Cela dégrade les performances de l'appareil. Considérant le peu de connaissances relatives à ce sujet, les avionneurs choisissent généralement des modifications empiriques pour y faire face. Cette thèse a consisté à étudier la dynamique d'un écoulement de jonction simplifié caractérisé par un décollement de coin modéré, et à évaluer des méthodes numériques couramment employées dans l'industrie pour la prévision de ces écoulements. Les travaux ont débuté avec une synthèse bibliographique. Les phénomènes présents au sein d'un écoulement de jonction simplifié ont été détaillés et les trois principaux sont le tourbillon en fer à cheval, le tourbillon de coin et le décollement de coin. Ensuite, à l'aide de l'approche numérique et de données expérimentales, il a été montré que le décollement de coin modifiait significativement le champ turbulent et que sa dynamique était apparentée à celle du tourbillon en fer à cheval. La comparaison de différents modèles de turbulence a confirmé que l'anisotropie de l'écoulement de coin devait être prise en compte dans la modélisation pour générer des simulations numériques comparables aux observations faites en soufflerie. L'étude du décollement de coin doit encore être poursuivie sur d'autres configurations pour permettre une éventuelle généralisation de ces résultats et les compléter. L'approche numérique doit aussi être améliorée afin de pourvoir à la complexification des situations, et l'utilisation de la ZDES mode 3 permettrait également de progresser dans la compréhension physique des écoulements de jonction. / Corner flow separation may occur on airplanes at the wing/fuselage junction for instance. Airplanes performances are then likely to be reduced. This issue is still not thoroughly understood and therefore, many wind-tunnel and flight tests are carried out in order to prevent the occurrence of this phenomenon. This thesis has consisted in studying the dynamics of a simplified junction flow characterized by the presence of a mild corner separation, and in investigating some of the standard CFD methods used in the industry for those kind of flows. First, a literature review showed that the main features of junction flows are the horseshoe vortex, the corner vortex and the corner separation. Thereafter, through the use of numerical and experimental data, it has been shown that the corner separation significantly influenced the turbulent field and its unsteady behavior was linked to the horseshoe vortex one. Comparisons between standard and advanced turbulence models have confirmed that second order closures are needed to accurately predict corner separations. Other juncture flows applications can still be further investigated in order to broaden the application spectrum of the present results. The understanding of the physics of juncture flows may also be improved, for instance using eddy resolving simulations such as ZDES mode 3. Robustness and accuracy of the advanced turbulent closures should be increased to allow reliable juncture flow computation at early design stages.
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Tight junction proteins and cancer-associated fibroblasts in ameloblastoma, ameloblastic carcinoma and mobile tongue cancerBello, I. O. (Ibrahim O.) 12 January 2010 (has links)
Abstract
Squamous cell carcinoma (SCC) of the mobile tongue is the most common type of cancer of the oral cavity, accounting for 30-40% of oral cancers. It behaves aggressively and almost half of the affected patients still die of the disease despite great advances in its medical and surgical care. Ameloblastomas are the most common clinically significant type of odontogenic tumors, constituting approximately 1% of all cysts and tumors of the jaw. They are benign but locally invasive tumors with a strong tendency to recur after surgery. Ameloblastic carcinoma combines the histological features of ameloblastoma with cytologic atypia irrespective of the presence or absence of metastasis.
The effectiveness of tight junction proteins (claudins 1, 4, 5, 7 and occludin) and cancer-associated fibroblasts (CAFs) as prognostic markers in OTSCC and as markers of malignancy in ameloblastomas was studied. Abundance of CAFs and Claudin 7 derangement was found to be associated with poor disease-specific survival in oral (mobile) tongue cancer. Appearance of CAFs within the epithelial islands of ameloblastoma was found to be a marker of malignancy in the tumor. The prognostic predictability of CAF density, Ki-67 (cell proliferation marker), maspin (tumor suppressor marker) and tumor DNA content (tumor ploidy using image cytometry) in tongue cancers was also tested. CAF density was the only marker strongly predictive of prognosis. In ameloblastomas, α-SMA (for CAFs), Ki-67, epithelial membrane antigen (EMA) and DNA content (using image and flow cytometry) were assessed as markers of ameloblastic carcinoma. Only α-SMA was able to predict ameloblastic carcinoma when found in the epithelial islands. In conclusion, staining for α-SMA and claudin 7 seems to be beneficial for prognostication in tongue cancer, while α-SMA staining may be beneficial in differentiating ameloblastoma from ameloblastic carcinoma.
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Surgically treated acute acalculous cholecystitis in critically ill patientsLaurila, J. (Jouko) 16 May 2006 (has links)
Abstract
Acute acalculous cholecystitis (AAC) is an insidious and increasingly recognized complication of critical illness, whose pathogenesis is poorly understood and clinical picture obscure. Diagnosis is difficult and there is no consensus on treatment.
The medical records of all ICU patients who had undergone open cholecystectomy due to AAC during the years 2000–2001 and 2003–2004 were examined for clinical and organ failure data. The indication for open cholecystectomy was a suspicion of AAC based on clinical signs and symptoms of sepsis or deteriorating multiple organ dysfunction without other obvious foci and/or radiological (computed tomography or ultrasound) findings indicative of cholecystitis.
A total of 73 patients had operatively treated AAC during the study periods, giving an incidence of 0.9% of all admissions (73/8184) and an incidence of 6.7% among the long-stayers (ICUstay >5 days). The hospital mortality of these patients was 43%. Infection was the most common admission diagnosis followed by cardiovascular surgery. The patients were severely ill, the mean (SD) APACHE II score being 25.5 (6.4) and the mean (SD) SOFA score 10.2 (3.5) on admission. In those patients who had AAC as the only intra-abdominal complication of multiple organ dysfunction, cholecystectomy was followed by a remarkable improvement of individual and total SOFA scores by the seventh postoperative day.
The AAC gallbladders were histologically and immunohistologically compared to normal gallbladders and to gallbladders of patients with acute calculous cholecystitis (ACC). The ACC patients were admitted into hospital because of primary acute gallbladder disease, were treated on a normal ward and did not have severe sepsis or multiple organ dysfunction. The typical histopathological features of AAC (34 cases) in the gallbladder wall were bile infiltration, lymphatic dilatation and leucocyte margination of blood vessels, while epithelial degeneration and defects, widespread occurrence of inflammatory cells and extensive and deep muscle layer necrosis were typical features of ACC (28 cases).
Tight junction proteins (claudin-1, -2, -3, -4, occludin, ZO-1 and E-cadherin) were uniformly expressed in normal gallbladder epithelium, with the exception of claudin-2, which was present in less than half of the cells. In AAC, the expression of cytoplasmic occludin and claudin-1 was decreased compared to control group. In ACC, the expression of claudin-2 was increased, but the expression of claudin-1, -3 and -4, occludin and ZO-1 was decreased compared to normal or AAC gallbladders.
In conclusion, AAC is associated with severe illness, infection, long intensive care unit stay and deteriorating multiple organ dysfunction. Open cholecystectomy is one important contributing factor to reverse the course of multiple organ dysfunction in these patients. Histological and immunohistological studies suggest that AAC is a manifestation of systemic inflammatory disease, while ACC is a local inflammatory and often infectious disease.
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