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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.
141

Polimorfismo por Random Amplified Polymorphic DNA (RAPD) em metacestódeos de Taenia solium provenientes de diferentes áreas geográficas do Brasil e a reatividade de anticorpos IgG séricos de pacientes com neurocisticercose frente aos isolados obtidos

Barcelos, Ivanildes Solange da Costa 07 April 2006 (has links)
Neurocysticercosis (NC) is a polymorphic disease and the immune response in human carrier is heterogenic. In this study, 35 primers were used for amplifications by Random Amplified Polymorphic DNA (RAPD) of Taenia solium metacestodes, from five different geographic areas in Brazil: 1) Distrito Federal (DF), Center West; 2) Barreiras (BA), Northeast and Southeast; 3) Hydro Basin of the Mosquito River (North of Minas Gerais, RM-MG), 4) São Paulo (SP) and 5) Uberaba (Minas Gerais, UB-MG). Metacestodes saline crude extracts of four populations (DF, BA, RM-MG e SP) were used for the detection of specific IgG antibodies by ELISA and Western Blotting (WB). A total of 157 serum samples of three groups, (G1): 49 NC patients; (G2): 68 patients with other helminthiasis: hydatidosis (10), taeniasis (20), strongyloidiasis (20), schistosomiasis (10) and hymenolepiasis (8); and (G3): 40 healthy individuals; were analyzed by ELISA. From these, the 98 serum samples were assayed by WB; G1 (49), G2 (39) and G3 (10). The genetic distances, in disagreement percentage, between the metacestode populations were calculated from of 15 RAPD markers and showed 49.5% (DF), 48% (BA), 38.5% (UBMG) and 28% (RM-MG and SP) of genetic distances. Six primers identified polymorphic fragments and the primers 26 (GGGTTTGGCA) and 29 (TCGCCAGCCA) allowed a better differentiation of populations. The fragments of 1000, 500 and 326 pb (pairs of bases) in the UB-MG and of 600 and 244 pb in RM-MG were amplified by primer 26. The fragments generated by primer 29 were 500, 800 and 1191 pb, 300 and 1377 pb, 1000 pb and 244 and 434 pb in SP, UB-MG, DF and BA populations, respectively. In G1, the positivity by ELISA was: 90% (DF), 69% (BA), 71% (MG) and 67% (SP). The DF extract was more antigenic than others (p=0.02). In WB, the 64-68 kDa antigens were recognized in all extracts, exclusively, in serum samples from active NC patients (p=0.001). Variation in banding pattern was detected between the extracts (p<0.05). In G2, the serum samples of hydatidosis patients presented from 70 to 90% positivity by ELISA in antigenic extracts (p<0.05); however, the bands recognition pattern in WB was different from that presented in G1 samples. The 77 kDa band was significantly identified in hydatidosis samples (p=0.0001). In conclusion, the T. solium populations analyzed showed genetic variability and antigenic differences. / A neurocisticercose (NC) constitui doença polimórfica, apresentando heterogeneidade da resposta imune no hospedeiro humano. Nesse estudo, o teste Random Amplified Polymorphic DNA (RAPD) foi utilizado com 35 primers na detecção de polimorfismo em metacestódeos de Taenia solium provenientes de cinco áreas geográficas distintas do Brasil: 1) Distrito Federal (DF), região Centro-Oeste; 2) Barreiras (BA), região nordeste e da região sudeste: 3) Bacia Hidrográfica do Rio Mosquito (norte de Minas Gerais, RM-MG), 4) São Paulo (SP) e 5) Uberaba (Minas Gerais, UB-MG). Os extratos salinos totais de metacestódeos de quatro populações (DF, BA, RM-MG e SP) foram utilizados na detecção de anticorpos IgG específicos pelo ELISA e Western Blotting (WB). As 157 amostras de soro de três grupos (G) de indivíduos: G1: 49 pacientes com NC; G2: 68 pacientes com outras helmintíases, sendo hidatidose (10), teníase (20), estrongiloidíase (20), esquistossomose (10) e himenolepíase (8) e G3: 40 indivíduos saudáveis (controles); foram analisadas pelo ELISA. Foram ensaiadas 98 amostras de soro: G1 (49), G2 (39) e G3 (10) pelo WB. As distâncias genéticas, por porcentagem de desacordo, foram de 49,5% (DF), 48% (BA), 38,5% (UB-MG) e 28% (RM-MG e SP) nas populações de metacestódeos, calculadas a partir de 15 marcadores de RAPD. Seis primers geraram fragmentos polimórficos nos isolados analisados, sendo que os primers 26 (GGGTTTGGCA) e 29 (TCGCCAGCCA) permitiram melhor diferenciação entre as populações, o primer 26 gerou os fragmentos de 1000, 500 e 326 pb (pares de bases) na amostra de UB-MG, e de 600 e 244 pb em RM-MG. O 29 gerou fragmentos em quatro das populações analisadas, sendo 500, 800 e 1191 pb em SP, 300 e 1377 pb em UBMG, 1000 pb no DF e 244 e 434 pb na BA. No G1, as freqüências de positividade no ELISA, foram: 90% (DF), 69% (BA), 71% (MG) e 67% (SP), sendo o extrato do DF mais antigênico que os demais (p = 0,02). No WB, o peptídeo de 64-68 kDa foi reconhecido em todos os extratos, exclusivamente, em amostras de pacientes com NC ativa (p=0,001). Detectou-se variação no padrão de reconhecimento de bandas entre os extratos (p<0,05). No G2, as amostras de soro de pacientes com hidatidose apresentaram de 70 a 90% de positividade no ELISA frente aos extratos analisados (p<0,05); porém, o padrão de reconhecimento de bandas no WB diferiu do apresentado pelas amostras do G1, sendo que a banda de 77 kDa foi significativamente identificada pelas amostras de pacientes com hidatidose (p=0,0001). Concluiu-se que as populações de T. solium analisadas nesse estudo, apresentaram variabilidade genética e diferenças de antigenicidade. / Doutor em Imunologia e Parasitologia Aplicadas
142

Fatores associados à hidrocefalia em pacientes com mucopolissacaridose

Dalla Corte, Amauri January 2017 (has links)
Introdução: As mucopolissacaridoses (MPS) constituem um grupo de doenças lisossômicas caracterizadas pela deficiência de uma das enzimas responsáveis pela degradação dos glicosaminoglicanos (GAGs). É difícil determinar a incidência precisa de hidrocefalia em pacientes com MPS, pois não possui uma definição formal por consenso. Além disso, é difícil distinguir a hidrocefalia comunicante da dilatação ventricular secundária à atrofia cerebral, porque ambas apresentam características clínicas e neuroradiológicas comuns. Embora várias técnicas sejam usadas para identificar pacientes com MPS com maior probabilidade de ter hidrocefalia e responder ao tratamento cirúrgico, não existe um método definitivo para provar o diagnóstico. Objetivos: Avaliar a relação entre ventriculomegalia, volume cerebral e liquórico, fluxo de líquor aquedutal e cervical e pressão de abertura liquórica em pacientes com MPS, e detectar potenciais biomarcadores para as alterações da circulação liquórica. Métodos: Quarenta e três pacientes com MPS (12 MPS I, 15 MPS II, 5 MPS III, 9 MPS IV A e 2 MPS VI) realizaram testes clínicos e de desenvolvimento neurológico, ressonância magnética (RM) nas sequências T1, T2, FLAIR e por contraste de fase, seguidas por punção lombar para avaliação da pressão de abertura liquórica. Para a análise das variáveis da RM, foram medidos: volume cerebral e liquórico, carga de lesões na substância branca (LSB), índice de Evans, largura do terceiro ventrículo, ângulo do corpo caloso, espaços perivasculares dilatados (EPVD), estenose da junção craniocervical, volume de stroke aquedutal e cervical, e concentração de GAGs no líquor. Resultados: As formas graves e a macrocefalia estiveram significativamente associadas com a ventriculomegalia, principalmente com o índice de Evans (p = 0.004 e p = 0.008, respectivamente). A carga de LSB apresentou uma forte correlação com as medidas ventriculares e o volume liquórico ventricular (rs = 0.51, p = 0.001). A dilatação ventricular supratentorial e o volume de líquor ventricular apresentaram uma correlação moderada com o volume de stroke aquedutal (VSA) (rs = 0.46, p = 0.002). A pressão de abertura liquórica não se correlacionou nem com as três medidas da ventriculomegalia, nem com a volumetria liquórica, nem com o VSA. O prejuízo cognitivo e os EPVD mostraram uma associação significativa com a ventriculomegalia, especialmente com a largura do terceiro ventrículo (p = 0.019 e p = 0.001, respectivamente). Os EPVD em quantidade aumentada também apresentaram uma significativa associação com o VSA elevado (p = 0.007). Conclusões: Nos pacientes com MPS, a ventriculomegalia está associada a um fenótipo grave da doença, maior declínio cognitivo e maior extensão das LSB e EPVD. Existem associações entre as medidas de fluxo liquórico e as medidas relacionadas à volumetria liquórica. Além disso, as medidas volumétricas estão associadas a quantidade de EPVD. / Background: The mucopolysaccharidoses (MPS) are a group of lysosomal diseases characterized by a deficiency in one of the lysosomal enzymes responsible to degrade glycosaminoglycans (GAGs). The precise incidence of hydrocephalus in patients with MPS is hard to determine, because it lacks a formal, consensus-based definition. In addition, it is difficult to distinguish communicating hydrocephalus from ventricular dilatation secondary to brain atrophy, because both share common clinical and neuroradiological features. Although various techniques are used to identify MPS patients who are most likely to have hydrocephalus and respond to surgical treatment, no definitive method exists to prove diagnosis. Objectives: To assess the relationship between ventriculomegaly, brain and cerebrospinal fluid (CSF) volumes, aqueductal and cervical CSF flows, and CSF opening pressure in MPS patients, and to provide potential biomarkers for abnormal CSF circulation. Methods: Forty-three MPS patients (12 MPS I, 15 MPS II, 5 MPS III, 9 MPS IV A and 2 MPS VI) performed clinical and neurodevelopmental tests, and T1, T2, FLAIR and phase-contrast magnetic resonance imaging (MRI) followed by a lumbar puncture with the CSF opening pressure assessment. For the analysis of MRI variables, the following measures were performed: brain and CSF volumes, white matter (WM) lesion load, Evans’ index, third ventricle width, callosal angle, dilated perivascular spaces (PVS), craniocervical junction stenosis, aqueductal and cervical CSF stroke volumes, and CSF GAGs concentration Results: The severe forms and the macrocephaly were significantly associated with the ventriculomegaly, mainly with the Evans’ index (p = 0.004 and p = 0.008, respectively). The WM lesion load presented a high correlation with the ventricular measurements and the ventricular CSF volume (rs = 0.51, p = 0.001). The supratentorial ventricular dilation and the ventricular CSF volume presented a moderate correlation with the aqueductal CSF stroke volume (ACSV) (rs = 0.46, p = 0.002). The CSF opening pressure did not correlate with either the three measures of ventriculomegaly, either with the CSF volumetry or with the ACSV. The cognitive impairment and the dilated PVS showed a significant association with the ventriculomegaly, especially with the width of the third ventricle (p = 0.019 and p = 0.001, respectively). Increased amount of dilated PVS also had a significant association with the elevated ACSV (p = 0.007). Conclusions: In MPS patients ventriculomegaly is associated with a severe phenotype, increased cognitive decline, WM lesion severity and enlarged PVS. There are associations between CSF flow measurements and measurements related to CSF volumetrics. Also, the volumetric measurements are associated with the degree of dilated PVS.
143

Análise da dinâmica da melatonina liquórica. / Analysis of the dynamic of liquoric melatonin.

Rosana Fátima Dantas Ferreira 15 December 2010 (has links)
O hormônio melatonina é produzido pela glândula pineal de mamíferos de forma circadiana e sua secreção é mais elevada durante a noite. Melatonina é liberada no sistema ventricular cerebral através do recesso pineal do 3º ventrículo. Sabe-se que a concentração de melatonina é maior nos ventrículos cerebrais que no plasma e no líquido cerebroespinhal lombar. Para avaliar a dinâmica da melatonina liquórica no rato Wistar, coletamos, através de microdiálise, amostras do líquor do terceiro ventrículo cerebral de animais jovens. Para avaliar a variação ontogenética em sua produção e liberação compararam-se as concentrações de melatonina liquórica em animais jovens e idosos. Observou-se também o perfil da melatonina liquórica em animais pinealectomizados. Esses procedimentos darão base para uma análise sistemática da dinâmica da melatonina no líquido cerebroespinal ventricular. / The hormone melatonin is produced by the mammalian pineal gland in a circadian way and its secretion is higher at night. Melatonin is released to the cerebral ventricular system through the pineal recess of the III ventricle. We know that the concentration of melatonin is higher in the cerebral ventricles than in plasma and lumbar cerebrospinal fluid. To evaluate the dynamic of melatonin in the cerebrospinal fluid (CSF) in Wistar rats, we collected, using microdialisys, samples of cerebrospinal fluid in the III ventricle of young animals. To estimate the ontogenetic decrease in melatonin production and release we compared the concentrations of CSF melatonin in young and aged animals. The concentration of CSF melatonin was also evaluated in pinealectomized rats. These procedures will elucidate the dynamic of ventricular CSF melatonin.
144

Neurocisticercose: relação entre dosagem de antígenos de Taenia no líquido cefalorraquidiano e imagem através de ressonância magnética / Neurocysticercosis: relationship between Taenia antigen detection in the cerebrospinal fluid and magnetic resonance imaging

Ronaldo Abraham 17 November 2006 (has links)
Neurocisticercose (NC) é a doença parasitária mais comum do SNC, representando grave problema de saúde pública em nosso país. O diagnóstico da NC é baseado em dados clínicos e epidemiológicos, reações sorológicas no soro e LCR, além de exames de neuroimagem. A detecção de antígenos de Taenia através de teste de ELISA, mediante a utilização de anticorpos altamente purificados, constitui metodologia recente capaz de informar sobre a vigência de atividade clínica da doença. O objetivo deste estudo foi determinar a relação entre a dosagem de antígenos de Taenia mo LCR com as imagens obtidas através da RM, em pacientes com o diagnóstico definido de NC segundo os critérios diagnósticos atuais. Sessenta e três pacientes foram submetidos a exame detalhado do LCR, além de pesquisa de antígeno de Taenia através de teste de ELISA, utilizando anticorpos de soro de coelhos imunizados com líquido vesicular de Taenia crassiceps. Uma amostra de sangue foi colhida simultaneamente à coleta do LCR, e um exame de RM encefálica foi realizado em todos os pacientes. Observamos relação significativa entre a detecção de antígenos de Taenia e o número total de lesões e do número de cistos íntegros detectados pela RM. Quando comparados dois ou mais cistos em degeneração com apenas um cisto, observamos detecção significativamente mais alta no primeiro grupo. Encontramos também detecção de antígenos significativamente mais alta quando as lesões se localizavam na profundidade dos hemisférios cererbrais, mas não na presença de cistos calcificados. Os resultados demonstram que a detecção de antígenos de Taenia se mostra congruente com os achados de neuroimagem. Algumas outras variáveis estudadas no LCR, como número de células, teor de globulinas gama e teste de ELISA, também se mostraram concordantes, demonstrando que a resposta inflamatória na NC mobiliza tanto a imunidade celular quanto a imunidade humoral. / Neurocysticercosis (NC) is the most common parasitic infection of the nervous system, remaining a serious public health in our country. NC diagnosis is supported by clinical and epidemiological data, specific serological reactions in the blood and CSF, and neuroimaging findings. Detection of anti-Taenia antigens using ELISA techniques is a recent methodology that provides information about clinical activity of the disease. The objective of the study was to determine relationship between Taenia antigen detection in the CSF and MRI in patients with definite diagnosis of NC according to current diagnostic criteria. Sixty-three patients were submitted to a thorough CSF examination and Taenia antigen research. Antigens were detected in CSF samples by ELISA assay obtained from rabbit sera antibodies immunized with Taenia crassiceps cysticerci vesicular fluid. A blood sample was simultaneously collected and a MRI was performed in every patient. We observed a significant relationship between Taenia antigen detection and the total number of lesions and intact cysts detected by MRI. When comparing two or more degenerating cysts with only one we observed a significant higher antigen detection in the first group. We also found a significant higher antigen detection when cysts were deeply located in the cerebral hemispheres, but not in the presence of calcified cysts. Results demonstrate that Taenia antigen detection is congruent with neuroimaging findings. Some CSF characteristics, like number of cells, gamma globulin concentration and ELISA assay were also concordant with Taenia antigen detection, indicating that inflammatory reaction in NC comprise cellular and humoral immunological factors.
145

CXCL13: A Prognostic Marker in Multiple Sclerosis

Havervall, Carolina January 2010 (has links)
In the demyelinating autoimmune disease multiple sclerosis (MS) there is a great need for validated prognostic biomarkers that can give information about both prognosis and disease course. So far only clinical parameters have been shown to predict future outcome. CXCL13 is a potent B cell chemoattractant that has been suggested to be a potential biomarker candidate. The aim of this study was to investigate the usefulness of CXCL13 as a prognostic biomarker for MS. Clinical, paraclinical, laboratory and MRI data about a large group of MS patients and controls were collected. CXCL13 levels in cerebrospinal fluid (CSF) samples from these patients were determined by standard enzymelinked immunosorbent assay (ELISA). In general CXCL13 were increased in CSF in MS, especially in relapsing-remitting MS during relapses, i.e. with ongoing inflammations in the central nervous system. CXCL13 is a good candidate prognostic marker for MS, since newly diagnosed MS with high CXCL13 levels showed worsened disease course within five years. Most importantly, MS conversion occurred in higher rate in possible MS patients with high concentrations of CXCL13 in CSF, and in a shorter time point. This observation may support an early treatment decision in these patients. In conclusion, this study provides support for an association between CXCL13 levels in the CSF and later development of disease severity in MS.
146

Study on the cerebrospinal fluid volumes / Étude des volumes du liquide cérébrospinal

Lebret, Alain 05 December 2013 (has links)
Cette thèse contribue au manque d'outils informatiques pour l'analyse d'images médicales et le diagnostic, en particulier en ce qui concerne l'étude des volumes du liquide cérébrospinal. La première partie concerne la mesure du volume des compartiments du liquide à partir d'images corps entier, pour une population composée d'adultes sains et de patients atteints d'hydrocéphalie. Les images sont obtenues à partir d'une séquence IRM développée récemment et mettant en évidence le liquide par rapport aux structures voisines, de manière à faciliter sa segmentation. Nous proposons une méthode automatique de segmentation et de séparation des volumes permettant une quantification efficace et reproductible. Le ratio des volumes des compartiments sous-arachnoïdien et ventriculaire est constant chez l'adulte sain, ce qui permet de conserver une pression intracrânienne stable. En revanche, il diminue et varie fortement chez les patients atteints d'hydrocéphalie. Ce ratio fournit un index physiologique fiable pour l'aide au diagnostic de la maladie. La seconde partie de la thèse est consacrée à l'analyse de la distribution du liquide dans le compartiment sous-arachnoïdien intracrânial supérieur. Il convient de souligner que ce compartiment, particulièrement complexe d'un point de vue anatomique, demeure peu étudié. Nous proposons deux techniques de visualisation de la distribution du volume liquidien contenu dans ce compartiment, qui produisent des images bidimensionnelles à partir des images d'origine. Ces images permettent de caractériser la distribution du volume liquidien et de son réseau, tout en distinguant les adultes sains des patients souffrant d'hydrocéphalie / This work aims to contribute to the lack of computational methods for medical image analysis and diagnosis about the study of cerebrospinal fluid volumes. In the first part, we focus on the volume assessment of the fluid spaces, from whole body images, in a population consisting of healthy adults and hydrocephalus patients. To help segmentation, these images, obtained from a recent "tissue-specific" magnetic resonance imaging sequence, highlight cerebrospinal fluid unlike its neigh borhood structures. We propose automatic segmentation and separation methods of the different spaces, which allow efficient and reproducible quantification. We show that the ratio of the total subarachnoid space volume to the ventricular one is a proportionality constant for healthy adults, to support a stable intracranial pressure. However, this ratio decreases and varies significantly among patients suffering from hydrocephalus. This ratio provides a reliable physiological index to help in the diagnosis of hydrocephalus. The second part of this work is dedicated to the fluid volume distribution analysis within the superior cortical subarachnoid space. Anatomical complexity of this space induces that it remains poorly studied. We propose two complementary methods to visualize the fluid volume distribution, and which both produce two-dimensional images from the original ones. These images, called relief maps, are used to characterize respectively, the fluid volume distribution and the fluid network, to classify healthy adults and patients with hydrocephalus, and to perform patient monitoring before and after surgery
147

Physiological inputs to cerebrospinal fluid-contacting neurons / Apports physiologiques des neurones au contact du liquide céphalorachidien

Böhm, Urs Lucas 16 September 2016 (has links)
Les neurones au contact du liquide céphalorachidien (CSF-cNs) sont des cellules ciliées présentes tout autour du canal central de la moelle épinière. Ces cellules sont GABAergiques, déploient une brosse de microvillosités à l'intérieur de la lumière du canal et sont caractérisées par une expression du canal ionique Pkd2l1. Ceci les désigne comme de potentielles cellules sensorielles. Il a été montré que les CSF-cNs peuvent moduler la locomotion et qu'elles réagissent aux variations de pH in vitro. Cependant les modalités sensorielles transmises par ces cellules et leur implication dans la fonction locomotrice nous échappent encore. Dans ma thèse, j'étudie la fonction sensorielle des CSF-cNs dans la moelle épinière de la larve de poisson zèbre. En combinant le relargage de proton et l'imagerie pH avec l'imagerie calcique, nous avons pu montrer que les CSF-cNs répondent à des pics d'acidification in vivo et que cette réponse persiste dans des mutants pkd2l1. Nous démontrons également que les CSF-cNs ne sont pas activés de façon coordonnée lors de la locomotion fictive. Les mouvements actifs ou passifs de la queue conduisent toutefois à l'activation spécifique des CSF-cNs ipsilatérales de la contraction musculaire. Ces observations suggèrent que les CSF-cNs sont recrutées par une stimulation mécanique. Les mutants pkd2l1 ont montré une diminution de la réponse à la flexion active et passive de la queue et une diminution de la fréquence de battement de la queue. Dans son ensemble, le travail présenté ici met donc en évidence que les CSF-cNs répondent aux variations de pH in vivo et révèle leur rôle d'organe mécanosensoriel permettant la modulation du réseau locomoteur spinal. / Cerebrospinal fluid-contacting neurons (CSF-cNs) are ciliated cells surrounding the central canal. These cells are GABAergic, extend a brush of microvilli into the lumen and are specified by the expression of the transient receptor potential ion channel Pkd2l1. The atypical morphology of CSF-cNs and their location make them candidates for sensory cells. It has been shown that CSF-cNs modulate locomotion by projecting onto the locomotor central pattern generators (CPGs) and that CSF-cNs can react to changes of pH in vitro, but the sensory modality these cells convey to spinal circuits and their relevance to locomotion remain elusive. In my thesis I investigate the sensory function of CSF-cNs in the zebrafish larva spinal cord. By combining proton uncaging together with pH imaging and calcium imaging, we could show that CSF-cNs respond to pulses of acidification in vivo and that this response persists in pkd2l1 mutants. Using genetically encoded calcium sensors we showed that CSF-cNs are not coordinately activated during fictive locomotion. Active or passive tail movement, however, led to CSF-cN activation restrained to cells ipsilateral to muscle contraction. These observations suggest that CSF-cNs are recruited by ipsilateral muscle contraction and/or tail torsion. Pkd2l1 mutants showed a decreased response to active and passive bending of the tail and a subtle but consistent decrease of tail-beat frequency was observed in the startle response. Altogether, the presented work shows evidence that CSF-cNs respond to changes in CSF pH and reveals that CSF-cNs constitute a mechanosensory organ which operates during locomotion to modulate spinal CPGs.
148

Rôle du système plexus choroïde-liquide céphalorachidien dans la distribution des cellules immunes au sein du système nerveux central, exemple de l’encéphalomyélite auto-immune expérimentale / The choroid plexus-cerebrospinal fluid system are involved in the early infiltration of immune cells in central nervous system inflammation

Schmitt, Charlotte 11 January 2012 (has links)
Le système nerveux central est un site particulier vis-à-vis du système immunitaire, en raison de la présence de la barrière hémato-encéphalique et de la barrière sang-liquide céphalorachidien. Les plexus choroïdes ont été considérés comme une voie d’entrée de certains lymphocytes dans le système nerveux central. Et le liquide céphalo-rachidien a été considéré comme une voie préférentielle de circulation des cellules immune au cours de la surveillance neuro-immunitaire de l’ensemble des compartiments cérébraux, puisque le LCR circule des ventricules, aux espaces sous-arachnoïdiens ainsi qu’aux velum et citernes internes. L’implication du système plexus choroïdes-liquide céphalorachidien dans l’infiltration cellulaire et la distribution des différents effecteurs immuns a été évaluée. Premièrement, nous avons analysé la relation entre le LCR et la répartition des différentes cellules immune au sein du système nerveux central, dans deux modèles d’encéphalite autoimmune expérimentale, utilisé comme modèle de la sclérose en plaque. Deuxièmement, nous avons recherché les partenaires moléculaires pouvant être impliqués dans la mise en place d’une inflammation, tels que les molécules d’adhésion exprimés par l’épithélium choroïdien, et les chimiokines pouvant être sécrétées dans le liquide céphalorachidien. Nos résultats identifient les plexus choroïdes comme une source de chimiokines sécrétées dans le liquide céphalorachidien, ce dernier orchestrant la distribution des différents effecteurs immunitaire au cours de l’inflammation / The central nervous system is an immunologically specialized site, because of the blood-brain barrier and the blood-cerebrospinal fluid barrier. The choroid plexuses had been considered as a preferential site for the entry of lymphocytes into the CNS. And the cerebrospinal fluid has been considered as a preferential pathway of circulation for immune cells during physiological neuroimmune surveillance, in all cerebral compartments, as the cerebrospinal fluid circulates from the ventricles to the subarachnoid spaces as well as the velum and internal cisterns. We evaluate the involvement of the choroid plexus-cerebrospinal fluid system in the cerebral infiltration and distribution of immune cells in CNS inflammation. First we realized a time course analysis of the different type of immune cell association with the CSF-containing compartments in two experimental autoimmune encephalomyelitis, models of multiple sclerosis. Secondly, we analyzed the molecular partners that could be involved in CNS inflammation development, such as adhesion molecules expressed on the choroid plexus, and chemokines secreted into the cerebrospinal fluid. Results identified the choroid plexuses as a source of chemokines, released into the cerebrospinal fluid that orchestrates the immune cell invasion during CNS inflammation
149

Detecções moleculares de infecções herpéticas em pacientes imunocompetentes com disfunções neurológicas / Molecular detection of herpetic infections in immunocompetent patients with neurological disorders

Rimerio, Carla Aparecida Tavares, 1981- 28 August 2018 (has links)
Orientadores: Sandra Helena Alves Bonon, Anamarli Nucci, Sandra Cecilia Botelho Costa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-28T03:54:34Z (GMT). No. of bitstreams: 1 Rimerio_CarlaAparecidaTavares_D.pdf: 6984397 bytes, checksum: e5297c2f56a94baa8a9eb6aed8b782ee (MD5) Previous issue date: 2015 / Resumo: Atualmente, pacientes imunocompetentes e idosos estão recebendo maior atenção em relação às infecções virais. A reativação dos herpesvírus pode ocorrer eventualmente no sistema nervoso e a ausência de tratamento adequado pode causar sequelas. O teste padrão para a confirmação laboratorial da presença do DNA dos herpesvírus no sistema nervoso é a PCR no líquor e, neste trabalho utilizamos também o plasma como amostra-teste. Nosso objetivo foi determinar a incidência dos herpesvírus em pacientes com suspeita de infecções no sistema nervoso utilizando a nested PCR no líquor e comparar os resultados obtidos com a nested PCR realizada em DNA extraído de plasma, verificando a concordância entre eles. Foram incluídos no estudo 52 amostras de líquor e 52 amostras de plasma de pacientes imunocompetentes com sintomas clínicos de distúrbios no sistema nervoso. Os dados clínicos foram obtidos a partir das informações constantes dos prontuários médicos. Como resultados, em 27/52 (52%) pacientes, o DNA dos herpesvírus foi detectado pelo menos uma vez nas amostras de líquor pela nested PCR. Destas amostras 15/27 (55%) tinham hipótese diagnóstica inicial de encefalite. A ocorrência de monoinfecção foi de 10/27 (37%) dos pacientes. Coinfecção ocorreu em 17/27 (63%) dos pacientes positivos. Os vírus mais encontrados foram o Epstein-Barr e o citomegalovírus humano, com 12/27 (44%) e 15/27 (55%), respectivamente. Um paciente com hipótese inicial de encefalite que apresentou positividade para estes dois vírus foi a óbito por insuficiência aguda respiratória, epilepsia e encefalite. O Herpesvírus 1 foi observado em 5/27 (18%); herpesvírus 2 em 2/27(7%); varicela-zoster, 3/27 (11%); herpesvírus 6, 10/27 (37%) e herpesvírus 7, 9/27 (33%). O Herpesvírus 8 não foi detectado. Nas amostras de DNA extraído de plasma, a positividade para os herpesvírus foi de 32/52 (61%). Monoinfecção ocorreu em 13/32 (41%) e coinfecção ocorreu em 19/32 (59%). Herpesvírus tipo 1 ocorreu em 1/32 (3%); herpesvírus 2 em 2/32 (6%); Epstein-Barr em 5/32 (16%); citomegalovírus humano em 11/32 (34%); herpesvírus tipo 6 em 7/32 (22%); herpesvírus 7 em 5/32 (16%) e herpesvírus 8 em 1/32 (3%). Utilizando o teste de McNemar para análise de concordância entre os exames realizados com amostras de DNA extraídas de líquor com as de plasma, observamos que para os herpesvírus 1, 2, Epstein-Barr, citomegalovírus, herpesvírus tipos 6 e 7 positivos estudados, não houve diferença estatisticamente significativa entre os testes. Para os herpesvírus VZV e HHV-8, não foi possível avaliar, devido ao baixo número de casos positivos. A detecção qualitativa do DNA dos herpesvírus no plasma por nested PCR pode ser tão útil quanto a detecção do líquor ao longo do tempo para identificar os pacientes que apresentam distúrbios neurológicos causados por esses vírus, tanto imunocompetentes quanto imunodeprimidos. Sendo assim, neste estudo verificamos o papel que os herpesvírus humanos desempenham nas infecções do sistema nervoso em pacientes imunocompetentes, com foco nas hipóteses diagnósticas de infecção viral no sistema nervoso central e periférico. Com a detecção do DNA viral, o tratamento antiviral precoce poderá ser instituído para os vírus ao qual existem antivirais disponíveis. Avaliando a eficiência dos métodos de diagnóstico laboratorial baseado na detecção do DNA dos herpesvírus no plasma, os valores obtidos podem ser considerados em relação à especificidade, assim como os valores verdadeiros negativos podem ser detectados e o tratamento empírico pode ser evitado. Esses achados sugerem que mesmo ocorrendo resultados falso negativos, este teste poderá ser utilizado nos pacientes que enfrentam problemas relacionados à coleta do líquor / Abstract: Currently, immunocompetent and elderly patients are receiving more attention in relation to viral infections. Reactivation of herpesviruses may eventually occur in the nervous system and the absence of adequate treatment can cause sequels. The standard for laboratorial confirmation of the presence of herpesvirus DNA in the nervous system is PCR in the cerebrospinal fluid (CSF). In this study, it was also used plasma as a sample test. The aim was to determine the incidence of herpesviruses in patients with suspect of virus infections of the nervous system using nested PCR in cerebrospinal fluid and compare the results with nested PCR performed on DNA extracted from plasma, by checking the correlation between them. The study included 52 samples of CSF and plasma from 52 immunocompetent patients with clinical symptoms of disorders in the nervous system. Clinical data were obtained from the information contained in the medical records. As a result, in 27/52 (52%) patients, herpesvirus DNA was detected at least once in CSF samples by nested PCR. These samples, 15/27 (55%) had initial diagnosis of encephalitis. The occurrence of monoinfection was 10/27 (37%) patients. Coinfection occurred in 17/27 (63%) positive patients. The most prevalent viruses found were Epstein-Barr virus and human cytomegalovirus, with 12/27 (44%) and 15/27 (55%), respectively. A patient with initial hypothesis of encephalitis that was positive for these two viruses died due to acute respiratory failure, epilepsy and encephalitis. Herpesvirus simplex 1 was observed in 5/27 (18%); herpesvirus simplex 2 in 2/27 (7%); varicella-zoster, 3/27 (11%); herpesvirus 6, 10/27 (37%) and herpesvirus 7, 9/27 (33%). Herpesvirus 8 was not detected. In DNA samples extracted from plasma, herpesviruses were positive in 32/52 (61%). Monoinfection occurred in 13/32 (41%) and coinfection occurred in 19/32 (59%). Herpesvirus simplex 1 occurred in 1/32 (3%); herpesvirus simplex 2 in 2/32 (6%); Epstein-Barr 5/32 (16%); human cytomegalovirus in 11/32 (34%); herpesvirus 6 in 7/32 (22%); herpesvirus 7 in 5/32 (16%) and herpesvirus 8 in 1/32 (3%). Using McNemar's test for analysis of agreement between the tests performed with DNA samples extracted from CSF with the plasma were observed that for herpesvirus 1, 2, Epstein-Barr, cytomegalovirus, herpesvirus type 6 and 7 positive studied, there was no statistically significant difference between the tests. For VZV and HHV-8 herpesvirus, could not be assessed due to the low number of positive cases. The qualitative detection of herpesvirus DNA in plasma by nested PCR can be as useful as the detection of CSF over time to identify patients with neurological disorders caused by these viruses, both immunocompetent as immunocompromised. Therefore, in this study it was seem the role human herpesvirus infections play in the nervous system in immunocompetent patients, focusing on diagnoses of viral infection in the central and peripheral nervous system. With the detection of viral DNA, early antiviral therapy may be institute for the virus that are antivirals available. Evaluating the efficiency of laboratorial diagnostic methods based on detection of DNA of the herpesvirus in the plasma, values obtained can be considered in relation to specificity, as well as the true negative values can be detected and empiric treatment can be avoided. These findings suggest that even occurring false negative results, this test can be used in patients who have problems related to the collection of CSF / Doutorado / Clinica Medica / Doutora em Clínica Médica
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Two-Point Dynamic Observation of Alzheimer’s Disease Cerebrospinal Fluid Biomarkers in Idiopathic Normal Pressure Hydrocephalus / 特発性正常圧水頭症におけるアルツハイマー病脳脊髄液バイオマーカーの動的モニタリング

Jingami, Naoto 25 May 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22636号 / 医博第4619号 / 新制||医||1044(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 高橋 淳, 教授 古川 壽亮, 教授 村井 俊哉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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