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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Doença de Alzheimer: estudos sobre acurácia diagnóstica nos pacientes em uso de anticolinesterásicos e a percepção dos familiares quanto aos seus benefícios.

Piovesana, Magda Cristina Flaitt Sanches 03 December 2010 (has links)
Made available in DSpace on 2016-01-26T12:51:28Z (GMT). No. of bitstreams: 1 magdacristinaflaittsanchespiovesana_dissert.pdf: 1394131 bytes, checksum: c999c1d2fcb99fa0db69afa796196ce4 (MD5) Previous issue date: 2010-12-03 / This study was realized in the Neurogeriatrics Clinic Base Hospital of Medicine Faculty in Sao Jose do Rio Preto. Objective: To study the diagnostic accuracy in Alzheimer's disease in patients treated with cholinesterase inhibitors available by Pharmacy of Exceptional Medicines and verify the impact of this therapy by the perception of families or caregivers. Methods: Cross-sectional study (prospective) the sample selection was random, in the period between May 2008 and February 2010. The certification of the diagnosis of Alzheimer's disease followed NINCDS-ADRDA, complemented by Scale Clinical Evaluation of Dementia (CDR), Scale for the Assessment of Disability in Dementia (DAD) and interviews with family and / or caregiver (structured questionnaire). Statistically used - to cross-frequency tables, chi-square test, Fisher exact test, Kruskal-Wallis test, t-test and principal component analysis, a significance level of 5%. Results: Participants 106 patients, categorized into Group MC, when met criteria for AD and the DNMC when not fulfilled. In the MC Group was observed, higher age (mean 78anos), 85% of patients with MMSE lower than expected, worse performance on the DAD (median 25), according to the severity 37% were in the mild stage, 48% at moderate and 15% at severe stage, the treatment time was larger and in full doses of anticholinesterase. In the DNMC Group ages were younger (mean 74anos), 50% of patients with MMSE lower than expected, better performance in the DAD (median 75) with less treatment time and at subtherapeutic doses. In EQ, in relation to the memory of the MC Group all patients showed a deficit, 18% improved and 54% worsened; 13% in the DNMC Group showed no deficit, 48% improved and 13% xii worsened. In the assessment of temporal orientation in the MC group, 8% of the patients had no disorientation, 8% improved and 62% worsened, since the DNMC Group, 37% had no disorientation, 30% improved and 16% worsened. In Topographical orientation, in the patients in MC Group, 77% did not go out alone and in the DNMC Group 54% had no difficulty in orienting themselves. In the MC Group, 14 of the 15 neuropsychiatric symptoms were more often, only depression was higher in the DNMC. In carrying out activities of daily living, patients of MC Group worsened in all the items in relation to the DNMC Group. Conclusions: It was observed that 51% of patients using anticholinesterases did not meet criteria for the diagnosis of AD likely, older age was associated with the MC Group, which had downgraded MMSE, worse performance in DAD and in the QE. In Structured Questionnaire the patients of DNMC Group showed a different behavior, perhaps by having other diagnoses, presented better performance. / Estudo realizado no Ambulatório de Neurogeriatria do Hospital de Base da Faculdade de Medicina de São José do Rio Preto. Objetivos: Estudar a acurácia diagnóstica na Doença de Alzheimer nos pacientes em tratamento com anticolinesterásicos disponibilizados pela Farmácia de Medicamentos Excepcionais e verificar o impacto desta terapêutica pela percepção dos familiares ou cuidadores. Métodos: Estudo transversal (prospectivo); a seleção da amostra ocorreu de forma aleatória, no período compreendido entre maio de 2008 e fevereiro de 2010. A certificação do diagnóstico da Doença de Alzheimer obedeceu critérios do NINCDS-ADRDA, complementada pela Escala de Avaliação Clínica da Demência (CDR), Escala para Avaliação de Incapacidades na Demência (DAD) e entrevista com familiar e ou cuidador (Questionário estruturado). Estatisticamente utilizaram-se tabelas de frequências cruzadas, teste Qui-Quadrado, teste exato de Fisher, teste de Kruskal-Wallis, teste t e análise de componentes principais, nível de significância 5%. Resultados: Participaram 106 pacientes, categorizados em Grupo PC, quando preenchiam os critérios para DA e Grupo ÑPC quando não preenchiam. O Grupo PC constituiu-se de 52 pacientes e o Grupo ÑPC de 54 pacientes. No Grupo PC observou-se idade elevada (média 78anos), 85% dos pacientes com MEEM abaixo do esperado, desempenho pior na DAD (mediana 25); de acordo com a gravidade 37% estavam na fase leve, 48% na fase moderada e 15% na fase grave, o tempo de tratamento era maior e com doses plenas de anticolinesterásicos. No Grupo ÑPC as idades eram menores (média de 74anos), 50% dos pacientes com MEEM abaixo do esperado, desempenho x melhor na DAD (mediana 75), com menos tempo de tratamento e em doses subterapêuticas. No Questionário estruturado (QE), em relação à memória todos pacientes do Grupo PC apresentaram déficit, 18% melhoraram e 54% piorou e no Grupo ÑPC 13% não apresentaram déficit, 48% melhoraram e 13% piorou. Na avaliação da orientação temporal no Grupo PC, 8% dos pacientes não apresentaram desorientação, 8% melhoraram e 62% pioraram, já no Grupo ÑPC, 37% não apresentavam, 30% melhoraram e 16% pioraram. Na orientação topográfica, nos pacientes do Grupo PC, 77% não saíam sozinhos e no Grupo ÑPC 54% não apresentavam dificuldade em orientar-se. No Grupo PC, 14 dos 15 sintomas neuropsiquiátricos apresentavam maior freqüência; apenas depressão foi maior no Grupo ÑPC. No desempenho das Atividades de Vida Diária, os pacientes do Grupo PC pioraram em todos os itens em relação ao Grupo ÑPC. Conclusões: Foi observado que 51% dos pacientes que utilizavam anticolinesterásicos não preencheram os critérios para o diagnóstico de DA provável, idade elevada foi associada ao Grupo PC, que apresentou MEEM rebaixado, desempenho pior na DAD e no QE. No Questionário Estruturado os pacientes do Grupo ÑPC mostraram um comportamento diferente, talvez por ter outros diagnósticos, apresentaram desempenho melhor.
362

Morphometry of the human hippocampus from MRI and conventional MRI high field / Morphométrie de l'hippocampe humain à partir d'IRM conventionnelles et d'IRM à très haut champ

Gerardin, Emilie 13 December 2012 (has links)
L’hippocampe est une structure de substance grise du lobe temporal qui joue un rôle fondamental dans les processus de mémoire ainsi que dans de nombreuses pathologies (maladie d’Alzheimer, épilepsie, dépression...).Le développement de modèles morphométriques est essentiel pour étudier l’anatomie fonctionnelle de cette structure et les altérations associées à différentes pathologies. L’objectif de cette thèse est de développer et de valider des méthodes de morphométrie de l’hippocampe dans deux contextes distincts : l’étude de la forme externe de l’hippocampe à partir d’IRM conventionnelles (1.5T ou 3T) à résolution millimétrique, l’étude de sa structure interne à partir d’IRM 7T à très haute résolution spatiale. Ces deux contextes correspondent aux deux parties principales de la thèse.Dans une première partie, nous proposons une méthode pour la classification automatique de patients à partir de descripteurs morphométriques. Cette méthode repose sur une décomposition en harmoniques sphériques qui est combinée à un classifieur de type support vectormachine (SVM). La méthode est évaluée dans le contexte de la classification automatique de patients avec une maladie d’Alzheimer (MA), de patients mild cognitive impairment (MCI) et de sujets sains âgés. Elle est également comparée à d’autres approches et une validation plus exhaustive est proposée dans une population de 509 sujets issus de la base ADNI. Nous présentons enfin une autre application de la morphométrie pour l’étude des altérations structurelles associées au syndrome de Gilles de la Tourette.La seconde partie de la thèse est consacrée à la morphométrie de la structure interne de l’hippocampe à partir d’IRM à 7 Tesla. En effet, la structure interne de l’hippocampe est riche et complexe mais inaccessible à l’IRM conventionnelle. Nous proposons tout d’abord un atlas de la structure interne de l’hippocampe à partir de données postmortem acquises à 9.4T. Ensuite, nous proposons de modéliser la corne d’Ammon et le subiculum sous la forme d’un squelette et d’une mesure locale d’épaisseur. Pour ce faire, nous introduisons une méthode variationnelle originale utilisant des espaces de Hilbert à noyaux reproduisants. La méthode est ensuite validée sur l’atlas postmortem et évaluée sur des données in vivo de sujets sains et de patients avec épilepsie acquises à 7T. / The hippocampus is a gray matter structure in the temporal lobe that plays a key role in memory processes and in many diseases (Alzheimer's disease, epilepsy, depression ...).The development of morphometric models is essential for the study of the functional anatomy and structure alterations associated with different pathologies. The objective of this thesis is to develop and validate methods for morphometry of the hippocampus in two contexts: the study of the external shape of the hippocampus from conventional MRI (1.5T or 3T) with millimeter resolution, and the study of its internal structure from 7T MRI with high spatial resolution. These two settings correspond to the two main parts of the thesis.In the first part, we propose a method for the automatic classification of patients from shape descriptors. This method is based on a spherical harmonic decomposition which is combined with a support vector machine classifier (SVM). The method is evaluated in the context of automatic classification of patients with Alzheimer's disease (AD) patients, mild cognitive impairment (MCI) patients and healthy elderly subjects. It is also compared to other approaches and a more comprehensive validation is available in a population of 509 subjects from the ADNI database. Finally, we present another application of morphometry to study structural alterations associated with the syndrome of Gilles de la Tourette.The second part of the thesis is devoted to the morphometry of the internal structure of the hippocampus from MRI at 7 Tesla. Indeed, the internal structure of the hippocampus is rich and complex but inaccessible to conventional MRI. We first propose an atlas of the internal structure of the hippocampus from postmortem data acquired at 9.4T. Then, we propose to model the Ammon’s horn and the subiculum as a skeleton and a local measure thickness. To do this, we introduce a variational method using original Hilbert spaces reproducing kernels. The method is validated on the postmortem atlas and evaluated on in vivo data from healthy subjects and patients with epilepsy acquired at 7T.
363

Exploring Uncaria rhynchophylla and its chemical constituents for the treatment of Alzheimer's disease.

January 2013 (has links)
鉤藤是眾多用於治療神經性退行性疾病的傳統中藥複方的組成成份之一。文獻研究發現鉤藤提取物能夠顯著抑制β澱粉樣蛋白纖維的形成和拆卸預製β澱粉樣蛋白纖維。然而鉤藤作用於老年性癡呆模型的實驗研究還未見報道。本課題的研究目的是探討鉤藤提取物對認知功能的改善作用,從而篩選出鉤藤抗老年性癡呆的有效化學成份及探討鉤藤抗老年性癡呆有效化學成份的神經保護作用及其作用機理。 / 首先我們探討了70%乙醇鉤藤提取物對D-半乳糖引起小鼠認知功能障礙的改善作用。水迷宮試驗結果顯示鉤藤提取物(200 和400毫克/千克)能顯著改善D-半乳糖處理小鼠的空間學習和記憶能力。此外,鉤藤提取物(200 和400毫克/千克)還顯著提高D-半乳糖處理小鼠腦組織中乙醯膽鹼和還原型穀胱甘肽的含量,以及超氧化物歧化酶和過氧化氫酶的活性,同時也能降低D-半乳糖處理小鼠腦組織中乙醯膽鹼酯酶的活性和丙二醛的含量。以上研究結果表明鉤藤提取物能改善D-半乳糖處理小鼠認知功能障礙的作用可能是通過抑制腦組織中乙醯膽鹼酯酶的活性和提高腦組織的氧化能力而達成的。 / 其次,我們選用β澱粉樣蛋白引致PC12細胞神經毒性的體外細胞模型來跟蹤篩選出鉤藤提取物中抗老年性癡呆的有效活性成分。結果顯示從鉤藤提取物中分離出六個生物鹼,分別為柯諾辛堿,柯諾辛堿B,去氫鉤藤堿,異鉤藤堿,異去氫鉤藤堿和鉤藤堿。在這六個生物鹼中,只有鉤藤堿和異鉤藤堿具有顯著降低β澱粉樣蛋白導致PC12細胞的死亡,而異鉤藤堿是鉤藤提取物中對β澱粉樣蛋白所致的PC12細胞損傷有最強的保護作用。 / 在明確異鉤藤堿是鉤藤提取物中抗老年性癡呆的主要有效成分的研究基礎上,我們應用β澱粉樣蛋白所致PC12細胞的神經毒性的體外實驗模型來探討異鉤藤堿的神經保護作用及其作用機理。實驗結果顯示異鉤藤堿對β澱粉樣蛋白引起PC12細胞的神經毒性的保護作用呈良好的量效關係。異鉤藤堿對β澱粉樣蛋白引起PC12細胞的神經毒性的保護作用是通過抑制細胞內鈣離子的超載,氧化應激,tau蛋白的過度磷酸化和線粒體細胞凋亡。 此外,異鉤藤堿還顯著抑制3β糖原合成酶激酶的活性,同時啟動磷酸化磷脂醯肌醇3-激酶底物Akt,提示異鉤藤堿對β澱粉樣蛋白所致的PC12細胞的神經毒性的保護作用與PI3K/Akt/GSK3信號通路相關密切相關。 / 最後,我們進一步探討了異鉤藤堿對β澱粉樣蛋白致大鼠認知功能障礙的改善作用及其作用機理。研究結果表明異鉤藤堿(20和40毫克/千克/天)能顯著改善β澱粉樣蛋白所致的大鼠認知功能障礙(用水迷宮試驗來評價)及明顯增加海馬CA1區錐體細胞數目。同時,異鉤藤堿能顯著抑制β澱粉樣蛋白導致大鼠海馬的氧化應激,神經元凋亡以及tau蛋白過度磷酸化。此外,異鉤藤堿能顯著抑制3β糖原合成酶激酶的活性,啟動磷酸化磷脂醯肌醇3-激酶底物Akt,提示異鉤藤堿改善β澱粉樣蛋白導致大鼠認知功能障礙的作用機理與PI3K/Akt/GSK3信號通路相關。 / 綜上所述,鉤藤和異鉤藤堿具有顯著的抗老年癡呆的作用。異鉤藤堿的神經保護作用與其抑制β澱粉樣蛋白導致PC12細胞和大鼠海馬的氧化應激,神經元凋亡以及tau蛋白的過度磷酸化有關。異鉤藤堿神經保護的作用機理與PI3K/Akt/GSK3信號通路密切相關。以上研究結果提示異鉤藤堿具有很好的進一步開發成新的抗老年性癡呆製劑的應用前景。 / The stem with hooks of Uncaria rhynchophylla (Ramulus Uncariae cum Uncis) is a component herb of many traditional formulae for the treatment of neurodegenerative diseases. Previous studies have demonstrated that the extract of U. rhynchophylla inhibited beta-amyloid (Aβ) fibril formation and disassemble preformed Aβ fibrils. However, scientific evidence concerning the efficacy of U. rhynchophylla in Alzheimer’s disease (AD) experimental models is lacking. The present study aimed at investigating the cognition-improving effect of U. rhynchophylla, identifying the active anti-AD chemical constituents and elucidating the underlying mechanisms of neuroprotective action. / Firstly, we investigated whether 70% aqueous ethanol extract of U. rhynchophylla (EUR) could protect against D-galactose (D-gal)-induced cognitive deficits in mice. Mice were given a subcutaneous injection of D-gal (50 mg/kg) and orally administered EUR (100, 200, or 400 mg/kg) daily for 8 weeks. The results showed that EUR (200 or 400 mg/kg) significantly improved spatial learning and memory function in D-gal-treated mice as assessed by the Morris water maze test. In addition, EUR (200 or 400 mg/kg) significantly increased the levels of acetylcholine and glutathione, and the activities of superoxide dismutase and catalase, while it decreased the activity of acetylcholinesterase and the level of malondialdehyde in the brains of D-gal-treated mice. These results indicate that EUR was able to ameliorate cognitive deficits induced by D-gal in mice, and the observed pharmacological action may be mediated, at least in part, by the inhibition of acetylcholinesterase activity and the enhancement of the antioxidant status of the brain tissues. / Secondly, we tried to identify the active ingredients of U. rhynchophylla by a bioassay-guided fractionation approach using beta-amyloid (Aβ)-induced neurotoxicity in rat pheochromocytoma (PC12) cells, a well established cellular model of AD. As a result of this work, six alkaloids, namely corynoxine, corynoxine B, corynoxeine, isorhynchophylline, isocorynoxeine and rhynchophylline were isolated from the extract of U. rhynchophylla. Among them, only rhynchophylline and isorhynchophylline could significantly decrease Aβ-induced cell death in PC12 cells. Moreover, isorhynchophylline (IRN) was found to be the most active ingredient responsible for the protective action of U. rhynchophylla against Aβ₂₅₋₃₅-induced cell death. / Thirdly, the neuroprotective effects and its action mechanism of IRN against Aβ₂₅₋₃₅-induced neurotoxicity in PC12 cells, an in vitro experimental model of AD, were examined. The results showed that treatment with IRN dose-dependently protected PC12 cells against Aβ₂₅₋₃₅-induced neurotoxicity. The neuroprotective effect of IRN may be mediated, at least in part, by inhibiting the intracellular calcium overloading, oxidative stress, tau protein hyperphosphorylation and mitochondrial cellular apoptosis induced by Aβ₂₅₋₃₅. Moreover, IRN also inhibited the activity of glycogen synthase kinase (GSK)-3β, an important kinase responsible for tau protein hyperphosphorylation in the development of AD; and activated the phosphorylation of phosphatidylinositol 3-kinase (PI3K) substrate Akt, suggesting that the neuroprotective action of IRN is associated with inhibition of GSK-3β activity and activation of PI3K/Akt signaling pathway. / Finally, the ameliorating effect on cognitive deficits of IRN and its underlying mechanism of action in Aβ₂₅₋₃₅-treated rats were investigated. The results showed that oral administration of IRN with two different doses (20 or 40 mg/kg) for 21 days significantly ameliorated cognitive impairments and suppressed the oxidative stress, neuronal apoptosis, and tau protein hyperphosphorylation in the hippocampus of Aβ₂₅₋₃₅-treated rats. In addition, IRN also inhibited the activity of GSK-3β, and activated phosphorylation of phosphatidylinositol 3-kinase (PI3K) substrate Akt, suggesting that the amelioration of cognitive deficits by IRN is associated with inhibition of GSK-3β activity and activation of PI3K/Akt signaling pathway. / Taken together, these results confirmed the anti-AD effects of U. rhynchophylla and IRN. The neuroprotective action of IRN may be mediated via inhibition of oxidative stress, neuronal apoptosis and hyperphosphorylation tau protein induced by Aβ₂₅₋₃₅ in vitro and in vivo. The neuroprotective action of IRN is associated with the inhibition of GSK-3β activity and the activation of PI3K/Akt signaling pathway. These experimental findings render IRN a promising candidate worthy of further development into anti-AD pharmaceutical agents. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xian, Yanfang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 242-278). / Abstracts also in Chinese. / Abstract (English) --- p.I / 摘要 --- p.IV / Publications --- p.VII / Acknowledgements --- p.IX / Table of Contents --- p.X / List of Figures --- p.XXI / List of Tables --- p.XXVI / List of Abbreviation --- p.XXVII / Chapter Chapter One --- General Introduction / Chapter 1.1 --- Alzheimer’s Disease --- p.2 / Chapter 1.1.1 --- Symptoms --- p.2 / Chapter 1.1.2 --- Epidemiology --- p.4 / Chapter 1.1.3 --- Pathology --- p.5 / Chapter 1.1.4 --- Risk factors --- p.6 / Chapter 1.2 --- Pathogenesis of AD --- p.10 / Chapter 1.2.1 --- Neurotransmitter dysfunction --- p.10 / Chapter 1.2.1.1 --- Cholinergic system dysfunction --- p.10 / Chapter 1.2.1.2 --- Glutamatergic system dysfunction --- p.11 / Chapter 1.2.2 --- Hippocampus atrophy --- p.15 / Chapter 1.2.3 --- “Amyloid Cascade hypothesis --- p.18 / Chapter 1.2.4 --- Increased oxidative stress --- p.21 / Chapter 1.2.5 --- Increased neuronal apoptosis --- p.23 / Chapter 1.2.6 --- Mitochondrial dysfunction --- p.27 / Chapter 1.2.7 --- Calcium dysregulation --- p.31 / Chapter 1.2.8 --- Increased tau protein hyperphosphorylation --- p.34 / Chapter 1.2.9 --- GSK3 hypothesis of AD --- p.37 / Chapter 1.3 --- Animal Models of AD --- p.41 / Chapter 1.3.1 --- Non-transgenic animal models of AD --- p.42 / Chapter 1.3.1.1 --- Spontaneous models --- p.42 / Chapter 1.3.1.2 --- Scopolamine-induced rodent models --- p.43 / Chapter 1.3.1.3 --- Aluminum-induced rodent models --- p.44 / Chapter 1.3.1.4 --- D-galactose-induced rodent models --- p.45 / Chapter 1.3.1.5 --- Aβ infusion rodent models --- p.46 / Chapter 1.3.2 --- Transgenic animal models of AD --- p.48 / Chapter 1.3.2.1 --- Transgenic rodent models for AD --- p.49 / Chapter 1.3.2.2 --- AD models in D. rerio --- p.53 / Chapter 1.3.2.3 --- AD models in D. melanogaster --- p.54 / Chapter 1.3.2.4 --- AD models in C. elegans --- p.54 / Chapter 1.4 --- Treatments for AD --- p.55 / Chapter 1.4.1 --- Current symptomatic treatments --- p.56 / Chapter 1.4.1.1 --- AChEIs --- p.56 / Chapter 1.4.1.2 --- NMDA antagonist --- p.57 / Chapter 1.4.2 --- Disease-modifying approaches --- p.61 / Chapter 1.4.2.1 --- Amyloid-directed therapies --- p.61 / Chapter 1.4.2.2 --- Tau-directed therapies --- p.61 / Chapter 1.4.2.3 --- Anti-oxidant agents --- p.62 / Chapter 1.4.2.4 --- NSAIDs --- p.63 / Chapter 1.4.2.5 --- Estrogen replacement therapy (ERT) --- p.64 / Chapter 1.4.3 --- Herbal medicines --- p.67 / Chapter 1.5 --- Uncaria rhynchophylla --- p.69 / Chapter 1.5.1 --- Chemical constituents --- p.69 / Chapter 1.5.2 --- Alkaloids --- p.72 / Chapter 1.6 --- Pharmacological Activities of Uncaria rhynchophylla and Its Alkaloids --- p.75 / Chapter 1.6.1 --- Effects on cardiovascular system --- p.75 / Chapter 1.6.2 --- Effects on central nervous system --- p.77 / Chapter 1.6.3 --- Antioxidant activities --- p.79 / Chapter 1.6.4 --- Anti-inflammatory and analgesic effects --- p.80 / Chapter 1.6.5 --- Effects on platelet aggregation and thrombosis --- p.81 / Chapter 1.6.6 --- Other pharmacological effects --- p.81 / Chapter 1.7 --- Hypothesis and Objectives of the Present Study --- p.83 / Chapter Chapter Two --- Uncaria rhynchophylla Ameliorates Cognitive Deficits Induced by D-galactose in Mice / Chapter 2.1 --- Introduction --- p.86 / Chapter 2.2 --- Materials and Methods --- p.88 / Chapter 2.2.1 --- Drugs and chemical reagents --- p.88 / Chapter 2.2.2 --- Plant materials and extraction --- p.89 / Chapter 2.2.3 --- Animals --- p.90 / Chapter 2.2.4 --- Experimental design and drugs treatment --- p.90 / Chapter 2.2.5 --- Morris water maze test --- p.91 / Chapter 2.2.6 --- Preparation of brain tissue samples --- p.92 / Chapter 2.2.7 --- Measurement of intracellular ROS level --- p.92 / Chapter 2.2.8 --- Assay of MDA level --- p.92 / Chapter 2.2.9 --- Assay of GSH level --- p.93 / Chapter 2.2.10 --- Measurement of SOD activity --- p.93 / Chapter 2.2.11 --- Measurement of CAT activity --- p.94 / Chapter 2.2.12 --- Assay of Ach level --- p.94 / Chapter 2.2.13 --- Measurement of AChE activity --- p.95 / Chapter 2.2.14 --- Statistical analysis --- p.95 / Chapter 2.3 --- Results --- p.95 / Chapter 2.3.1 --- Quality determination of EUR --- p.95 / Chapter 2.3.2 --- Effects of EUR on Morris water maze in D-gal-treated mice --- p.97 / Chapter 2.3.3 --- Effects of EUR on the level of intracellular ROS in the brains of D-gal-treated mice --- p.101 / Chapter 2.3.4 --- Effects of EUR on the levels of GSH and MDA in the brains of D-gal-treated mice --- p.103 / Chapter 2.3.5 --- Effects of EUR on the activities of SOD and CAT in the brains of D-gal-treated mice --- p.105 / Chapter 2.3.6 --- Effects of EUR on the level of ACh and the activity of AChE in the brains of D-gal-treated mice --- p.107 / Chapter 2.4 --- Discussion --- p.109 / Chapter Chapter Three --- Bioassay-Guided Isolation of Neuroprotective Compounds from Uncaria rhynchophylla Against Beta-Amyloid-Induced Neurotoxicity / Chapter 3.1 --- Introduction --- p.113 / Chapter 3.2 --- Materials and Methods --- p.114 / Chapter 3.2.2 --- Drugs and chemical reagents --- p.114 / Chapter 3.2.2 --- Preparation of aggregated Aβ₂₅₋₃₅ --- p.115 / Chapter 3.2.3 --- Extraction, fractionation, isolation and identification processes --- p.115 / Chapter 3.2.4 --- Cell culture and drug treatment --- p.119 / Chapter 3.2.5 --- Cell viability assay --- p.119 / Chapter 3.2.6 --- Statistical analysis --- p.120 / Chapter 3.3 --- Results --- p.120 / Chapter 3.3.1 --- Isolation and structural determination of the isolated compounds --- p.120 / Chapter 3.3.2 --- Effects of different fractions and isolated compounds on Aβ₂₅₋₃₅-induced cells death in PC12 cells --- p.122 / Chapter 3.4 --- Discussion --- p.126 / Chapter Chapter Four --- Neuroprotective Effects of Isorhynchophylline Against Beta-Amyloid-Induced Neurotoxicity in PC12 Cells and Its Possible Mechanisms / Chapter 4.1 --- Introduction --- p.130 / Chapter 4.2 --- Materials and Methods --- p.131 / Chapter 4.2.1 --- Drugs and chemical reagents --- p.131 / Chapter 4.2.2 --- Cell culture and drugs treatment --- p.134 / Chapter 4.2.3 --- Cell viability assay --- p.134 / Chapter 4.2.4 --- Lactate dehydrogenase (LDH) activity assay --- p.135 / Chapter 4.2.5 --- Measurement of intracellular ROS production --- p.135 / Chapter 4.2.6 --- Malondialdehyde (MDA) and glutathione (GSH) assay --- p.136 / Chapter 4.2.7 --- Measurement of SOD activity --- p.137 / Chapter 4.2.8 --- Measurement of CAT activity --- p.137 / Chapter 4.2.9 --- Measurement of intracellular calcium concentration --- p.138 / Chapter 4.2.10 --- Measurement of mitochondrial membrane potential --- p.139 / Chapter 4.2.11 --- Quantification of DNA fragmentation --- p.139 / Chapter 4.2.12 --- Cytochrome c assay --- p.140 / Chapter 4.2.13 --- Western blotting analysis --- p.140 / Chapter 4.2.14 --- Real time-polymerase chain reaction (RT-PCR) analysis --- p.141 / Chapter 4.2.15 --- Statistical analysis --- p.142 / Chapter 4.3 --- Results --- p.143 / Chapter 4.3.1 --- Effects of IRN on Aβ₂₅₋₃₅-induced cytotoxicity in PC12 cells --- p.143 / Chapter 4.3.2 --- Effects of IRN on the level of intracellular ROS in Aβ₂₅₋₃₅-treated PC12 cells --- p.145 / Chapter 4.3.3 --- Effects of IRN on the levels of GSH and MDA in Aβ₂₅₋₃₅-treated PC12 cells --- p.147 / Chapter 4.3.4 --- Effects of IRN on the activities of SOD and CAT in Aβ₂₅₋₃₅-treated PC12 cells --- p.149 / Chapter 4.3.5 --- Effects of IRN on intracellular calcium level in Aβ₂₅₋₃₅-treated PC12 Cells --- p.151 / Chapter 4.3.6 --- Effects of IRN on MMP in Aβ₂₅₋₃₅-treated PC12 cells --- p.153 / Chapter 4.3.7 --- Effects of IRN on DNA fragmentation in Aβ₂₅₋₃₅-treated PC12 cells --- p.155 / Chapter 4.3.8 --- Effects of IRN on the release of cytochrome c in Aβ₂₅₋₃₅-treated PC12 cells --- p.157 / Chapter 4.3.9 --- Effects of IRN on the protein and mRNA levels of the ratio of Bcl-2/Bax in Aβ₂₅₋₃₅-treated PC12 cells --- p.159 / Chapter 4.3.10 --- Effects of IRN on the protein and mRNA levels of cleaved caspase-3 and caspase-9 in Aβ₂₅₋₃₅-treated PC12 cells --- p.162 / Chapter 4.3.11 --- Effects of IRN on the protein of pro-caspase-8 and mRNA levels of the full length of caspase-8 in Aβ₂₅₋₃₅-treated PC12 cells --- p.165 / Chapter 4.3.12 --- Effects of IRN on tau protein hyperphosphorylation in Aβ₂₅₋₃₅-treated PC12 Cells --- p.168 / Chapter 4.3.13 --- Effects of IRN on Aβ₂₅₋₃₅-induced activation of GSK-3β in PC12 cells --- p.170 / Chapter 4.3.14 --- Effects of IRN on Aβ₂₅₋₃₅-induced inactivation of PI3K/Akt pathway --- p.173 / Chapter 4.4 --- Discussion --- p.177 / Chapter Chapter Five --- Isorhynchophylline Treatment Improves Cognitive Deficits Induced by Beta-Amyloid in Rats: Involvement of PI3K/Akt Signaling Pathway / Chapter 5.1 --- Introduction --- p.186 / Chapter 5.2 --- Materials and Methods --- p.187 / Chapter 5.2.1 --- Drugs and chemical reagents --- p.187 / Chapter 5.2.2 --- Animals --- p.188 / Chapter 5.2.3 --- Aβ₂₅₋₃₅ injections --- p.188 / Chapter 5.2.4 --- Experimental design and drugs treatment --- p.189 / Chapter 5.2.5 --- Morris water maze test --- p.190 / Chapter 5.2.6 --- Nissl’s staining for neurons --- p.193 / Chapter 5.2.7 --- Preparation of brain tissue samples --- p.193 / Chapter 5.2.8 --- Measurement of intracellular ROS level --- p.194 / Chapter 5.2.9 --- Assay of MDA level --- p.194 / Chapter 5.2.10 --- Assay of GSH level --- p.195 / Chapter 5.2.11 --- Measurement of SOD activity --- p.195 / Chapter 5.2.12 --- Measurement of CAT activity --- p.195 / Chapter 5.2.13 --- Cytochrome c assay --- p.196 / Chapter 5.2.14 --- Western blotting analysis --- p.196 / Chapter 5.2.15 --- RT-PCR analysis --- p.197 / Chapter 5.2.16 --- Statistical analysis --- p.198 / Chapter 5.3 --- Results --- p.199 / Chapter 5.3.1 --- IRN treatment rescued behavioral impairment in the Morris water maze test --- p.199 / Chapter 5.3.2 --- Effects of IRN on the number of pyramidal neuronal cells in the hippocampal CA1 region of Aβ₂₅₋₃₅-treated rats --- p.203 / Chapter 5.3.3 --- Effects of IRN on the intracellular ROS level in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.205 / Chapter 5.3.4 --- Effects of IRN on the levels of GSH and MDA in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.207 / Chapter 5.3.5 --- Effects of IRN on the activities of SOD and CAT in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.209 / Chapter 5.3.6 --- Effects of IRN on cytochrome c in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.211 / Chapter 5.3.7 --- Effects of IRN on the protein and mRNA level of the ratio of Bcl-2/Bax in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.213 / Chapter 5.3.8 --- Effects of IRN on the protein and mRNA levels of cleaved caspase-3 and caspase-9 in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.216 / Chapter 5.3.9 --- Effects of IRN on the protein and mRNA levels of caspase-8 in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.219 / Chapter 5.3.10 --- Effects of IRN on the tau protein hyperphosphorylation in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.222 / Chapter 5.3.11 --- Effects of IRN on the activation of GSK-3β in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.224 / Chapter 5.3.12 --- Effects of IRN on the PI3K/Akt pathway in the hippocampus of Aβ₂₅₋₃₅-treated rats --- p.226 / Chapter 5.4 --- Discussion --- p.228 / Chapter Chapter Six --- General Discussion and Future Perspectives / Chapter 6.1 --- General Discussion and Conclusions --- p.237 / Chapter 6.2 --- Future Perspectives --- p.243 / References by Alphabetical Order --- p.246
364

Study of neuroprotective effect of cryptotanshinone, an acetylcholinesterase inhibitor, in cell and animal models. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Alzhemier's disease (AD) is a common form of dementia which is characterized by the deposition of amyloids in affected neurons and a cholinergic neurotransmission deficit in the brain. Current therapeutic intervention for AD is primarily based on inhibition of brain acetylcholinesterase (AChE) to restore the brain acetylcholine level. Cryptotanshinone (CT) is a diterprene which is extracted from the root of Salvia miltiorrhiza, an herb that is commonly prescribed in Chinese medicine to treat cardiovascular disease. The present study is aimed at verifying CT's property as an AChE inhibitor using different models. By AChE activity assay, CT was found to be a dual inhibitor which inhibits both human acetylcholinesterase (AChE) and butylcholinesterase (BuChE) with similar IC50. CT inhibited human AChE in a reversible manner, and the inhibition showed the characteristics of mixed-type. To human BuChE, CT is an uncompetitive inhibitor. CT can also inhibit AChE from rat cortical neurons. Apart from AChE inhibition, CT was demonstrated to have ameliorating effect on glutamate excitotoxicity, which is a cause of neuron death in AD. Further study showing that CT treatment can reduce cellular tau phosphorylation, which is the downstream effector of glutamate-induced excitotoxicity. In animal model, the effect of CT on learning impairment in scopolamine-treated rats was also evaluated by the acquisition protocol of Morris water maze. The task learning ability of scopolamine-treated rats was significantly reversed by CT, and the CT-fed rats were able to develop spatial searching strategy comparable to the control animals. Chronic administration of CT at effective doses did not cause significant hepatotoxicity. Cholinergic side effect of muscle weakness was not observed in CT treated rats. On the contrary CT was found to increase the locomotor activity of NIH mice in forced swimming test through reducing the lactic acid in the circulation. Data in this study gives further support on CT's potential as a therapeutic drug for treating AD. / by Wong, Kin Kwan Kelvin. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 144-167). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
365

Biomarcadores na doença de Alzheimer: GSK3B e PLA2 na resposta aos inibidores de colinesterase / Biomarkers in Alzheirmer\'s disease: GSK3B and PLA2 in response to cholinesterase inhibitors

Leda Leme Talib 23 May 2014 (has links)
A Doença de Alzheimer (DA) é uma desordem neurodegenerativa progressiva que causa comprometimento cognitivo e demência. O diagnóstico é baseado em parâmetros clínicos, mas sua confirmação é post-mortem, após avaliação patológica durante a autópsia. Os tratamentos disponíveis para a DA são os inibidores da colinesterase (IChEs) e os antagonistas de receptores de N-metil-D-aspartato (NMDA), sendo que os IChEs compõe o principal grupo. Diversos estudos tem mostrado um efeito neuroprotetor dos IChEs, levando a alterações na patogênese da DA. Avaliar e mensurar essas alterações são papeis atribuídos aos biomarcadores. Neste sentido podemos destacar a fosfolipase A2 (PLA2), a principal responsável pelo metabolismo de fosfolípides de membrana, e que tem sido achada diminuída na DA, assim como a glicogênio sintase-quinase (GSK), responsável pela fosforilação da proteína Tau, que é um dos processos alterados na DA. O objetivo deste trabalho foi avaliar o efeito do tratamento com IChE sobre a atividade da PLA2 e expressão da GSK3B em plaquetas de 30 pacientes com DA após 3 e 6 meses de tratamento. Como grupo controle foram investigados 42 individuos idosos sem doença neurodegenerativa. Encontramos nos pacientes com DA antes do tratamento uma diminuição da atividade da iPLA2 quando comparada ao grupo controle. Após três e seis meses de tratamento a PLA2 aumentou, voltando ao nível dos controles. Os pacientes que apresentaram um aumento maior da iPLA2 apos 3 meses de tratamento apresentaram melhora cognitiva mais marcante após seis meses de tratamento, avaliado pelo CAMCOG. Apos 6 meses de tratamento encontramos um inativação da GSK3B, medida por um aumento em sua forma fosforilada. Nossos resultados sugerem que o donepezil apresenta propriedades modificadoras na doença de Alzheimer, e ainda que a medida da atividade da iPLA2 poderia ser usada como marcador de resposta terapêutica ao donepezil e, possivelmente, a outros IChEs, na doença de Alzheimer / Alzheimer\'s disease (AD) is a progressive neurodegenerative disorder that causes dementia and cognitive impairment. The Diagnosis is based on clinical parameters, but confirmation is post-mortem after pathologic evaluation during autopsy. The treatments available for AD are cholinesterase inhibitors (IChEs) and N-methyl-D-aspartate (NMDA) antagonists. The main group comprises the IChEs. Several studies have shown a neuroprotective effect of IChEs, leading to alterations in the pathogenesis of AD. Evaluate and measure these changes are assigned to biomarkers. In this regard we can highlight the phospholipase A2 (PLA2) the main enzyme in membrane phospholipids metabolism and that has been found decreased in AD as well as Glycogen Synthase kinase (GSK), a major responsible for tau phosphorylation which is one processes altered in AD. The objective of this study was to evaluate the effect of treatment with IChE on PLA2 activity and GSK3B expression in platelet of 30 AD patients after 3 and 6 months of treatment. The control group comprised 42 elderly individuals without neurodegenerative disease The results obtained were a decreased iPLA2 activity in patients with AD before treatment as compared to controls. After 3 and 6 months of treatment, we observed a significant increase in iPLA2 activity, restoring enzymatic activity similar to that observed among control. The patients who showed higher iPLA2 activity in the first three months were those showing cognitive improvement after six months of treatment, measured by CAMCOG. After 6 months of treatment a GSK3B inactivation were found, measured by an increase in its phosphorylated form. Our results suggest that donepezil present modifying properties in Alzheimer disease and that iPLA2 activity measurement could be used as a marker of therapeutic response to donepezil and possibly other IChEs in Alzheimer\'s disease
366

"Polimorfismos da região promotora e codificadora do gene APOE e do gene LRP na doença de Alzheimer em indivíduos brasileiros" / Polymorphisms of the APOE and LRP and Alzheimer's disease in Brazilian individuals

Bahia, Valéria Santoro 15 September 2003 (has links)
Objetivos: Analisar a relevância dos polimorfismos da APOE, -491 e -219 e do LRP na ocorrência de doença de Alzheimer (DA) em indivíduos brasileiros. Metodologia: Realizou-se o estudo em 120 pacientes com DA provável e em 120 controles. Resultados: Houve diferença quanto à freqüência do alelo e4 da APOE, (31% dos pacientes e 10% dos controles). A presença do alelo e2 conferiu efeito protetor. Os polimorfismos das posições -219 e -491 da APOE e do gene LRP não mostraram correlação com DA. Conclusões: O alelo e4 do gene APOE mostrou-se associado a maior risco de DA e o alelo e2 conferiu efeito protetor. Não foi encontrada correlação entre DA e os outros polimorfismos / OBJETIVE: To investigate the role of polymorphisms APOE,-491 and -219 and LRP patients with Alzheimer's disease (AD) and controls in Brazilian individuals.METHODS: One hundred twenty patients and 120 controls were selected for the assessment. RESULTS: The frequency of the e4 allele was 0.31 in patients and 0.10 in controls. The presence of allele e2 was protective factor. No significant difference emerged for the polymorphisms of the localization -219 and -491 of APOE and of the LRP gene. CONCLUSION: These results confirm the relevance of the e4 allele like genetic risk factor and the protective role of the e2 allele in AD. We did not notice any difference in patients and controls for polymorphisms of the LRP and APOE promoter region polymorphism in this study
367

<i>IN VIVO</i> OXIDATIVE STRESS IN ALZHEIMER DISEASE BRAIN AND A MOUSE MODEL THEREOF: EFFECTS OF LIPID ASYMMETRY AND THE SINGLE METHIONINE RESIDUE OF AMYLOID-β PEPTIDE

Bader Lange, Miranda Lu 01 January 2010 (has links)
Studies presented in this dissertation were conducted to gain more insight into the role of phospholipid asymmetry and amyloid-β (Aβ)-induced oxidative stress in brain of subjects with amnestic mild cognitive impairment (aMCI) and Alzheimer disease (AD). AD is a largely sporadic, age-associated neurodegenerative disorder clinically characterized by the vast, progressive loss of memory and cognition commonly in populations over the age of ~65 years, with the exception of those with familial AD, which develop AD symptoms as early as ~30 years-old. Neuropathologically, both AD and FAD can be characterized by synapse and neuronal cell loss in conjunction with accumulation of neurofibrillary tangles and senile plaques. Elevated levels of oxidative stress and damage to brain proteins, lipids, and nucleic acids are observed, as well. Likewise, aMCI, arguably the earliest form of AD, displays many of these same clinical and pathological characteristics, with a few exceptions (e.g., no dementia) and to a lesser extent. Studies in this dissertation focused on the contributions of oxidative stress to the exposure of phosphatidylserine (PtdSer) to the outer-leaflet of the lipid membrane, how and when PtdSer asymmetric collapse contributes to the progression of aMCI, AD, and FAD, and the role played by methionine-35 (Met-35) of Aβ in oxidative stress and damage, as measured in a transgenic mouse model of Aβ pathology. Normally, the PtdSer is sequestered to the cytosolic, inner-leaflet of the bilayer by the adenosine triphosphate (ATP)-dependent, membrane-bound translocase, flippase, which unidirectionally transports PtdSer inward against its concentration gradient. Oxidative stress-induced modification of flippase and/or PtdSer, however, leads to prolonged extracellular exposure of PtdSer on the outer membrane leaflet, a known signal for both early apoptosis and selective recognition and mononuclear phagocytosis of dying cells. Within the inferior parietal lobule (IPL) of subjects with aMCI and AD, a significant collapse in PtdSer asymmetry was found in association with increased levels of both pro- and anti-apoptotic proteins, Bax, caspase-3, and Bcl-2. Moreover, a significant collapse in PtdSer asymmetry was also found in whole brain of human double-mutant knock-in mouse models of Aβ pathology, together with significantly reduced Mg2+ATPase activity, representing flippase activity, and increased levels of pro-apoptotic caspase-3. Significant PtdSer externalization corresponded to the age at which significant soluble Aβ(1-42) deposition occurs in this particular mouse model (9 months), and not of plaque deposition (12 months), suggesting that elevated levels of Aβ(1-42), together with increasing oxidative stress and apoptosis, may contribute to altered PtdSer membrane localization. Also in this dissertation, transgenic mice carrying Swedish and Indiana mutations on the human amyloid precursor protein (APPSw,In) and APPSw,In mice carrying a Met35Leu mutation on Aβ were derived to investigate the role of Met-35 in Aβ(1-42)-induced oxidative stress in vivo. Oxidative stress analyses revealed that Aβ-induced oxidative stress requires the presence of Met-35, as all indices of oxidative damage (i.e., protein carbonylation, nitration, and protein-bound 4-hydroxy-2-trans-nonenal [HNE]) in brain of Met35Leu mice were completely prevented. Moreover, immunohistochemical analyses indicated that the Met35Leu mutation influences plaque formation, as a clear reduction in Aβ-immunoreactive plaques in Met35Leu mice was found in conjunction with a significant increase in microglial activation. In contrast, behavioral analyses suggested that spatial learning and memory was independent of Met-35 of Aβ, as Met35Leu mice demonstrated inferior water-maze performance compared to non-transgenic mice. Differential expression and redox proteomic analyses to pinpoint proteins significantly altered by the APPSw,In and Met35Leu mutations was performed, as well. Expression proteomics showed significant increases and decreases in APPSw,In and Met35Leu mouse brain, respectively, in proteins involved in cell signaling, detoxification, structure, metabolism, molecular chaperoning, protein degradation, mitochondrial function, etc. Redox proteomics found many of these same proteins to be oxidatively modified (i.e., protein carbonylation and nitration) in both APPSw,In and Met35Leu mouse brain, providing additional insights into the critical nature of Met-35 of Aβ for in vivo oxidative stress in a mammalian species brain, and strongly suggesting similar importance of Met-35 of Aβ(1-42) in brain of subjects with aMCI and AD. Taken together, studies presented in this dissertation demonstrate the role of oxidative stress-induced alteration of PtdSer asymmetry and Met-35 in Aβ-induced oxidative stress in aMCI, AD, and FAD brain.
368

Aspects on clinical diagnosis of dementia, with focus on biological markers / Katarina Nägga.

Nägga, Katarina, January 2004 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 4 uppsatser.
369

Intracellular dynamics of Alzheimer disease-related proteins /

Selivanova, Alexandra, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
370

Neuronal dysfunction and degeneration in Alzheimer's disease and brain trauma

Payette, Daniel January 2008 (has links) (PDF)
Thesis (Ph. D.)--University of Oklahoma. / Includes bibliographical references.

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