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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.
341

Non-Motor Symptoms in Patients Suffering from Motor Neuron Diseases

Günther, Rene, Richter, Nicole, Sauerbier, Anna, Chaudhuri, Kallol Ray, Martinez-Martin, Pablo, Storch, Alexander, Hermann, Andreas 19 January 2017 (has links) (PDF)
Background The recently postulated “disease spreading hypothesis” has gained much attention, especially for Parkinson’s disease (PD). The various non-motor symptoms (NMS) in neurodegenerative diseases would be much better explained by this hypothesis than by the degeneration of disease-specific cell populations. Motor neuron disease (MND) is primarily known as a group of diseases with a selective loss of motor function. However, recent evidence suggests disease spreading into non-motor brain regions also in MND. The aim of this study was to comprehensively detect NMS in patients suffering from MND. Methods We used a self-rating questionnaire including 30 different items of gastrointestinal, autonomic, neuropsychiatric, and sleep complaints [NMS questionnaire (NMSQuest)], which is an established tool in PD patients. 90 MND patients were included and compared to 96 controls. Results In total, MND patients reported significantly higher NMS scores (median: 7 points) in comparison to controls (median: 4 points). Dribbling, impaired taste/smelling, impaired swallowing, weight loss, loss of interest, sad/blues, falling, and insomnia were significantly more prevalent in MND patients compared to controls. Interestingly, excessive sweating was more reported in the MND group. Correlation analysis revealed an increase of total NMS score with disease progression. Conclusion NMS in MND patients seemed to increase with disease progression, which would fit with the recently postulated “disease spreading hypothesis.” The total NMS score in the MND group significantly exceeded the score for the control group, but only 8 of the 30 single complaints of the NMSQuest were significantly more often reported by MND patients. Dribbling, impaired swallowing, weight loss, and falling could primarily be connected to motor neuron degeneration and declared as motor symptoms in MND.
342

Eficácia de diferentes dispositivos de interação em tarefa virtual na esclerose lateral amiotrófica / Efficacy of different task virtual interaction devices in amyotrophic lateral sclerosis

Isabela Lopes Trevizan 06 July 2016 (has links)
Introdução: A Esclerose Lateral Amiotrófica (ELA) é uma neuronopatia de curso progressivo, caracterizada pela morte dos neurônios motores superiores e inferiores. Devido a rápida progressão da doença e ao aparecimento dos sintomas de incapacidade funcional os indivíduos com ELA buscam uma forma alternativa de comunicação e interação. Com isso, o desenvolvimento tecnológico utilizando programas de realidade virtual com ajuda de dispositivos de interação pode viabilizar mais função e auxiliar indivíduos com ELA a obter autonomia, independência, melhor qualidade de vida e inclusão. Objetivo: Identificar qual dispositivo de interação virtual é melhor para propiciar desempenho e funcionalidade em uma tarefa de realidade virtual para indivíduos com ELA. Método: Participaram do estudo 30 indivíduos que formaram o grupo ELA e 30 indivíduos com desenvolvimento típico que formaram o grupo controle, com idade entre 44 a 74 anos, pareados por idade e sexo. A tarefa utilizada, foi um jogo no computador, que consiste em estourar o maior número de bolhas possíveis durante 30 segundos. Os indivíduos foram separados em 3 grupos, cada qual utilizando uma interface diferente (Kinect, Leap Motion Controller ou Touchscreen) na fase de aquisição e retenção da tarefa. Após essas fases, foi realizada a fase de transferência com a troca de dispositivos e assim todos os grupos tiveram contato com todas as interfaces. Para análise estatística utilizou-se o número de bolhas alcançadas para cada participante, durante as fases de aquisição, retenção e transferências. Resultados: Todos os participantes, tanto do grupo ELA como do grupo controle, apresentaram melhor performance motora na utilização do dispositivo Touchscreen, porém o grupo ELA apresentou desempenho inferior com a prática de todos os dispositivos. A prática com o dispositivo Touchscreen não permitiu a transferência para os dispositivos Leap Motion Controller e Kinect, isso significa que a prática com dispositivo de característica mais real (Touchscreen) não permitiu a transferência para os dispositivos com características mais virtuais (Kinect® e Leap Motion Controller®), porém considerando a prática com os dispositivos virtuais essa transferência ocorre. Conclusão: O trabalho apresenta um avanço na compreensão de dispositivos apropriados para a utilização na reabilitação da funcionalidade de indivíduos com ELA. O dispositivo Touchscreen foi o que apresentou melhor desempenho funcional para essa população, podendo oferecer mais funcionalidades para os indivíduos na execução de tarefas virtuais / Introdution: Amyotrophic Lateral Sclerosis (ALS) is a progressive course of neuronopathy, characterized by the motor neurons death (MN) upper and lower. Due to rapid disease progression and the onset of symptoms of functional disability individuals with ALS seek an alternative form of communication and interaction. Technological development using virtual reality programs with the help of interaction devices can offer more function and assist individuals with ALS to obtain autonomy, independence, quality of life and inclusion. Objective: to identify which low-cost non-immersive interaction device, using a virtual task, is better for providing performance and functionality for individuals with ALS. Method This is an analytical cross-sectional study. A total of 60 people participated in this study, 30 individuals with ALS (18 men and 12 women, mean age = 59 years, range 44-74 years), while 30 people with normal development that were matched for age and gender with individuals with ALS formed the control group. The task used was a computer game, which consists of blowing the largest possible number of bubbles for 30 seconds. The subjects were divided into 3 groups, each using a different interface (Kinect®, Leap Motion Controller® or Touchscreen) in the task acquisition and retention stage. After these phases was carried out the transfer phase with the switching devices, then all groups had contact with all interfaces. For statistical analysis we used the number of bubbles achieved for each participant during the phases of acquisition, retention and transfer. Results: All participants, both the ALS group, both the control group showed better motor performance in the use of the Touchscreen device, but the ALS group had underperformed the practice of all devices. Practice with the touchscreen device did not allow the transfer to the Leap Motion Controller® and Kinect® devices, this means that the practice more real feature device (Touchscreen) did not allow the transfer to devices with more virtual features (Kinect® and Leap Motion controller®), but considering the practice with virtual devices that transfer occurs. Conclusion: This work presents a breakthrough in the understanding of appropriate devices for use in the rehabilitation of people with ALS functionality. The Touchscreen device showed the best functional performance for this population and can offer more features for individuals in executing virtual tasks
343

A VAPB e a Esclerose Lateral Amiotrófica / VAPB and Amyotrophic Lateral Sclerosis

Melinda Santos Beccari 23 September 2015 (has links)
A Esclerose Lateral Amiotrófica (ELA) é uma doença crônica, progressiva e neurodegenerativa causada pela morte dos neurônios motores. O diagnóstico destes pacientes pode levar até 12 meses para acontecer, sendo que estes vão à óbito entre 3-5 anos do início dos sintomas. Há, porém, grande variabilidade de quadro clínico, com alguns pacientes falecendo com menos de 1 ano do início dos primeiros sinais, e outros que sobrevivem por décadas. A identificação da ELA8, causada por uma mutação missense no gene VAPB (c.C166T, p.P56S), tem contribuído significativamente com o conhecimento dos mecanismos moleculares por trás da ELA. A literatura recente tem evidenciado que a diminuição dos níveis de VAPB está presente em modelos celulares e murinos da doença, e também em amostras de pacientes, sugerindo que esta proteína teria papel central na doença e uma contribuição significativa para a morte dos neurônios motores. O presente trabalho buscou três objetivos principais: (1) o diagnóstico molecular através de um painel de sequenciamento de nova geração que inclui os genes SOD1, FUS, TARDBP, SETX, SPG11, FIG4 e VAPB; (2) a avaliação dos níveis de RNAm de VAPA, VAPB e EPHA4 em pacientes de ELA8, controles familiares e outros pacientes de ELA, com o intuito de investigar possíveis papéis destes genes na doença; e por fim, (3) o desenvolvimento de um ensaio quantitativo para as proteínas VAPA, VAPB e VAPC baseado em cromatografia líquida acoplada à espectrometria de massas em tandem (LC-MS/MS), para a posterior avaliação de VAPB como possível biomarcador em ELA, e de suas isoformas VAPA e VAPC como modificadores da doença. Para a análise genômica, foram avaliados 67 pacientes, sendo que 31 (ou 46%) apresentaram a mutação c.C166T em VAPB; 4 pacientes (6%) em SOD1, sendo que um destes apresentou uma mutação também em FIG4; 1 paciente (1.5%) foi identificado uma mutação patogênica em FUS; outro, duas mutações deletérias em trans em SPG11. Os níveis de RNAm de VAPB, VAPA e EPHA4 não são estatisticamente distintos entre pacientes e controles; porém, os níveis de EPHA4 estavam significativamente elevados em dois pacientes de início bulbar da doença. Para o desenvolvimento do método quantitativo por LC-MS/MS, foram escolhidos 8 peptídeos inequívocos para análise, estabelecidos dos parâmetros de corrida, e desenvolvidos dois padrões internos (linhagens SILAC e VAPB recombinante) para a quantificação. Esta ferramenta desenvolvida poderá auxiliar não apenas os estudos moleculares que envolvem os mecanismos por trás ELA8, responsável por uma elevada taxa dos casos familiais brasileiros, mas também poderá determinar o potencial de VAPB como biomarcador para Esclerose Lateral Amiotrófica / Amyotrophic Lateral Sclerosis is a chronic, progressive neurodegenerative disorder caused by the death of motor neurons. Diagnosis can take up to 12 months, with no molecular marker to expedite this process. In this scenario, patients die within 3 to 5 years of symptom onset, although a large clinical variability is seen, with severe patients dying less than one year after onset, and others surviving for decades. The identification of ALS8, caused by a missense mutation in the VAPB gene (c.C166T; p.P56S), has contributed significantly to the knowledge of molecular mechanisms behind ALS. Recent literature has evidenced that the decrease of VAPB levels is present in cellular and murine models, and also in patient samples, suggesting a central role in motor neuron death in ALS. The present work sought three main objectives: (1) a molecular diagnosis through a NGS sequencing panel including the SOD1, FUS, TARDBP, SETX, SPG11, FIG4 and VAPB genes; (2) analyze the expression levels of VAPA, VAPB and EPHA4 in patients, family controls and other forms of ALS, in order to investigate their possible roles in ALS8; and (3) the development of a targeted quantitative mass spectrometry based assay, gold standard in protein quantification due to its precision and sensitivity, for the VAPA, VAPB and VAPC proteins, seeking the analysis of VAPB as a potential biomarker in ALS and of its isoform\'s potential roles as modifiers in the disease. The genomic analyses revealed that out of 67 patients, 31 presented the ALS8 mutation in VAPB, 4 patients (6%) presented a mutation in SOD1, with one patient carrying a second mutation in FIG4; 1 (1.5%) patient was identified with a pathogenic mutation in FUS; and another presented two pathogenic mutations in trans in the SPG11 gene. Thus, we were able to diagnose over half of the patients included in this study with a panel of only 7 genes. VAPB, VAPA and EPHA4 mRNA levels are not statistically different between patients and controls; however, EPHA4 was shown to be highly elevated in two bulbar-onset non-ALS8 patients. For the development of the LC-MS/MS targeted assay, 8 surrogate peptides were chosen for analysis, run parameters were established, and two internal standards for quantification were developed (SILAC cell lines and recombinant VAPB). This tool will prove to be useful not only towards elucidating the molecular mechanisms behind ALS8, one of the most prevalent forms of familial ALS in Brazil, but also to determine VAPB\'s potential as a biomarker for ALS
344

Danos em DNA promovidos pela enzima Cu,Zn-superóxido dismutase. Implicações para a apoptose em um modelo celular de esclerose lateral amiotrófica / DNA damage promoted by Cu,Zn-Superoxide Dismutase. Implications to apoptosis in a cellular model of Amyotrophic Lateral Sclerosis

Lívea Fujita Barbosa 10 November 2008 (has links)
Mutações na enzima Cu,Zn-superóxido dismutase (SOD1) estão associadas a casos familiares de Esclerose Lateral Amiotrófica (ELA), uma doença neurodegenerativa motora fatal. Entretanto, a toxicidade das SOD1s mutantes não está totalmente compreendida. Sabe-se que o desenvolvimento da doença está associado ao acúmulo de lesões oxidativas em biomoléculas, mas o papel da SOD1 neste processo não está claro. Estudos com sistemas modelo são, ainda, necessários para desvendar os mecanismos envolvidos. Para contribuir na compreensão dos mecanismos de danos em DNA promovidos pela SOD1, foram realizados estudos in vitro com SOD1/H2O2/HCO3-, e estudos com neuroblastomas em cultura transfectados com SOD1 mutante G93A, característica de ELA. Através da quantificação de quebras em DNA plasmidial e dos níveis de 8-oxo-7,8-dihidro-2´-desoxiguanosina (8-oxodGuo) e 1,N2-eteno-2\'-desoxiguanosina (1,N2-εdGuo) em DNA de timo de bezerro, concluiu-se que o cobre liberado da SOD1 tem um papel central na formação de lesões no DNA promovidas pela SOD1 na presença de H2O2, e que o bicarbonato pode modular a reatividade do cobre liberado. Níveis aumentados de quebras no DNA, 8-oxodGuo e 1,N2-εdGuo foram encontrados nos neuroblastomas transfectados com SOD1 G93A. Maior atividade de p53 foi também observada nestas células, indicando que o acúmulo de lesões no DNA pode desencadear o processo de apoptose neste modelo celular de ELA. Observou-se que a SOD1 pode estar associada à cromatina, e que a SOD1 G93A possui maior afinidade pelo DNA e maior atividade peroxidásica no núcleo. Estes resultados indicam que as lesões no DNA observadas no modelo celular de ELA podem ser diretamente promovidas pela SOD1 mutante. / Mutations in the gene encoding Cu,Zn-superoxide dismutase (SOD1) have been linked to familial Amyotrophic Lateral Sclerosis (ALS), a fatal motor neuron disease. However, the toxicity of mutant SOD1s was not completely understood. It is known that the development of the disease is associated with oxidative damage to biomolecules, but the role of SOD1 in this process is not clear. Model studies are still necessary to reveal the mechanisms involved. To understand the mechanism of DNA damage promoted by SOD1, in vitro studies with SOD1/H2O2/HCO3-, and studies with neuroblastoma cells transfected with the G93A ALS-mutant SOD1, were performed. Through the quantification of strand breaks in plasmid DNA and the quantification of 8-oxo-7,8-dihydro-2´-deoxyguanosine (8-oxodGuo) and 1,N2-etheno-2\'-deoxyguanosine (1,N2-εdGuo) levels in calf thymus DNA, it was concluded that copper liberated from SOD1 has a central role in DNA damage promoted by SOD1 in the presence of H2O2, and that bicarbonate can modulate the reactivity of released copper. Increased levels of DNA strand breaks, 8-oxodGuo and 1,N2-εdGuo were found in neuroblastoma cells transfected with G93A SOD1. Increased p53 activity was also observed in these cells, indicating that accumulation of DNA damage can lead to apoptosis in this ALS cellular model. Western blot analysis showed that G93A SOD1 is present in the nucleus, being associated to the DNA. Nuclear G93A SOD1 has identical superoxide dismutase-activity but displays increased peroxidase activity, when compared to wild-type. These results indicate that DNA damage observed in this ALS cellular model may be directly promoted by mutant SOD1.
345

Modificações em proteínas induzidas por compostos eletrofílicos. possível papel em esclerose lateral amiotrófica / Modifications in proteins induced by electrophilic compounds. Possible role in amyotrophic lateral

Adriana Pereira Domarques de Menezes 13 November 2017 (has links)
Danos em biomoléculas podem ocorrer a partir de uma interação direta entre as biomoléculas e espécies reativas de oxigênio e nitrogênio como também, pela reação de produtos secundários dessas espécies como eletrófilos gerados na peroxidação lipídica. Alguns desses produtos secundários possuem estabilidade química maior que as espécies reativas das quais foram derivadas e podem se ligar covalentemente as biomoléculas comprometendo o funcionamento normal das mesmas. Portanto, modificações em proteínas por aldeídos gerados na lipoperoxidação têm sido investigadas por suas implicações com desordens patológicas relacionadas à agregação proteica, e modificações em diversas vias de sinalização amplificando os efeitos deletérios em sistemas biológicos. Os objetivos desse trabalho foi contribuir na elucidação dos mecanismos moleculares associados ao desenvolvimento da esclerose lateral amiotrófica (ELA) através da identificação, caracterização e quantificação de modificações póstraducionais em proteínas pelos aldeídos 4-hidroxi-2-hexenal (HHE) e trans-4-hidroxi-2-nonenal (HNE) in vitro (citocromo c) e in vivo (modelo ELA) a partir de técnicas de Western blot, imunoprecipitação e espectrometria de massa com abordagem proteômica de \"shotgun\" em ratosSOD1G93A modelo de esclerose lateral amiotrófica (ELA). Estudos com citocromo c mostraram a ligação dos aldeídos ao citocromo c e mecanismos de reação foram propostos. Foram encontrados seis peptídeos modificados por HHE e um para o HNE, e o peptídeo TGPNLHGLFGR se mostrou modificado pelos dois aldeídos paralelamente. Foi demonstrado que a histidina 33 é um \"hot spot\" frente as adições pelos aldeídos. Nas análises por western blot das proteínas ligadas a aldeídos foi possível observar uma tendência de aumento na concentração de proteínas ligadas ao HNE nos animais ELA, mais acentuada nas amostras de 70 dias comparadas ao controle. Com relação aos resultados obtidos com HHE tanto os animais pré-sintomáticos quanto os sintomáticos não apresentaram diferenças de HHE-proteína, tantonos controles quanto nos animais ELA. Nas amostras dos animais sintomáticos não detectamos diferença significativa na concentração de aldeído-proteína entre os grupos. Já as análises proteômicas revelaram 24 proteínas diferencialmente expressas, com destaque para proteínas com os maiores valores de significância (p-value), como a ubiquitina no grupo dos pré- sintomáticos e a neurogranina, no grupo dos animais sintomáticos e várias proteínas de metabolismo energético, de neurofilamentos, proteínas de processos redox e proteínas ligadas o metabolismo de cálcio (fundamentais na fisiopatologia em ELA). Algumas proteínas importantes foram encontradas com exclusividades nos grupos pré-sintomáticos e sintomáticos pelo diagrama de Venn. Com relação a proteínas modificadas pelos aldeídos, foram encontradas algumas relevantes como a proteína 2 de interação com a polimerase delta que foi modificada por HNE via adição de Michael encontrada nos animais ELA pré-sintomáticos e sintomáticos, a catalase que foi encontrada modificada por HNE via base de Schiff apenas nos ELA pré- sintomáticos, e a tiol redutase induzível por interferon gama no grupo dos animais ELA sintomáticos. Com relação a proteínas modificadas por HHE, foram encontradas a Janus quinase e proteína 3 de interação com microtúbulo, modificadas tanto por adição de Michael quanto via base de Schiff nos animais ELA sintomáticos. É interessante ressaltar que algumas modificações encontradas em proteínas não caracterizadas podem indicar proteínas novas ainda não descritas como modificadas por esses aldeídos. Os resultados mostram que algumas das proteínas modificadas por HNE e HHE encontradas neste trabalho, estão relacionadas ao estresse redox, vias metabólicas energéticas, proteínas envolvidas na resposta a danos oxidativos, e processos inflamatórios. Tais modificações ocorrem não só no modelo de neurodegeneração, mas foram previamente descritas em outros processos patológicos, como doença cardiovascular, lesão hepática por uso crônico de álcool. / Damage to biomolecules can occur from a direct interaction between biomolecules and reactive of oxygen and nitrogen species as well as from the reaction of secondary products of these species as electrophiles generated in lipid peroxidation. Some of these by-products have greater chemical stability than the derived reactive species and can bind to biomolecules compromising their normal function. Therefore, protein modifications by aldehydes generated during lipoperoxidation have been investigated for their implications with pathological disorders related to protein aggregation and modifications in signaling pathways amplifying the deleterious effects in biological systems. The aim of this work was to contribute to the elucidation of the molecular mechanisms associated with the development of amyotrophic lateral sclerosis (ALS) through the identification, characterization and quantification of posttranslational modifications in proteins by 4-hydroxy-2-hexenal (HHE) and trans-4-hydroxy-2- nonenal (HNE) in vitro, cytochrome c, and in vivo, rat model (SOD1G93A) of amyotrophic lateral sclerosis (ALS), throught Western blot techniques, and mass spectrometry with shotgun proteomics approach. The results showed the binding of aldehydes to cytochrome c. Six peptides were modified by HHE and one by HNE. The peptide TGPNLHGLFGR was modified by the two aldehydes. Histidine 33 has been shown to be a hot spot against aldehydes additions. By western blot analysis of the aldehyde-bound proteins, it was possible to observe a tendency of increase in the concentration of HNE-bound proteins in the ALS animals, more pronounced in the samples of 70 days compared to control samples. Regarding the results obtained with HHE, both pre-symptomatic and symptomatic animals did not show HHE-protein differences, both in controls and in ALS animals. We did not detect a significant difference in the aldehyde-protein concentration between the groups in the samples of the symptomatic animals. Proteomic analysis revealed 24 differentially expressed proteins, with emphasis on proteins with thehighest values of significance (p-value), such as the ubiquitin in the pre-symptomatic group and neurogranin in the group of the symptomatic animals and several proteins of the energetic metabolism pathways, neurofilaments, proteins of redox processes and proteins linked to calcium metabolism (fundamental in the pathophysiology of ALS). Some important proteins were found exclusivity in the pre-symptomatic and symptomatic groups by the Venn diagram. With regard to aldehyde-modified proteins, some relevant ones such as Delta-2 polymerase interaction protein, that was modified by HNE via the addition of Michael found in presymptomatic and symptomatic ELA animals, catalase that was found to be modified by HNE via Schiff\'s base only in pre-symptomatic ALS, and gamma interferon-inducible thiol reductase in the group of symptomatic ALS animals. Janus kinase and microtubule interaction protein 3, were found to be modified by Michael addition and Schiff base pathway respectively in symptomatic ALS animals. It is interesting to note that some modifications found in uncharacterized proteins may indicate new proteins not yet described as modified by these aldehydes. The results show that some of the proteins modified by HNE and HHE found in this work are related to redox stress, energetic metabolic pathways, proteins involved in the response to oxidative damage, and inflammatory processes. Such modifications occur not only in the neurodegeneration model, but were previously described in other pathological processes, such as cardiovascular disease, liver injury due to chronic alcohol use
346

Investigação de potenciais biomarcadores redox - um enfoque em aldeídos e seus produtos / Potential redox biomarkers investigation - focus on aldehydes and their products

Florêncio Porto Freitas 23 May 2014 (has links)
As espécies reativas são associadas a processos toxicológicos e fisiopatológicos, agindo como importantes mediadores, por exemplo, na sinalização celular. Diversas classes de compostos têm sido utilizadas como possíveis biomarcadores de estresse redox, destacando-se os aldeídos &#945;,&#946;-insaturados, capazes de alquilar biomoléculas como o DNA. Para evitar efeitos deletérios, estes aldeídos são detoxificados por glutationilação e posterior metabolização a derivados mercaptúricos. Contudo, avaliar o estado redox em sistemas biológicos ainda é tarefa bastante complexa, sendo a dificuldade em quantificar de forma prática e acurada os efeitos de sinalização e/ou dano molecular o maior problema dos estudos redox. Assim, o objetivo deste trabalho foi desenvolver métodos acurados e sensíveis de análise de potenciais biomarcadores de estresse redox, isto é: nucleosídeos modificados, aldeídos endógenos e exógenos, glutationa e produtos de glutationilação, e avaliá-los em sistemas modelos, celular e animal, e em humanos. A avaliação dos níveis urinários de três nucleosídeos modificados por metodologia de HPLC-MS/MS desenvolvida pelo grupo em moradores da cidade de São Paulo - região com poluição atmosférica - demonstrou aumento significativo de 1,N2-propanodGuo comparado aos moradores de região não poluída. Ademais, comprova-se pela primeira vez que células deficientes em reparo de ligações cruzadas apresentam níveis basais elevados de 1,N2-propanodGuo, em duas linhagens independentes, colocando este aduto como potencial mediador de carcinogênese em pacientes portadores de Anemia de Fanconi. Utilizando cérebro de ratos SOD1G93A (modelo de Esclerose Lateral Amiotrófica - ELA), verificou-se aumento de 50% nos níveis de 1,N2-propanodGuo e de 100% nos de 1,N6-&#949;dAdo em fase sintomática, sugerindo influência do conteúdo lipídico cerebral, levando a comprometimento do metabolismo neuronal e morte celular. O perfil de aldeídos determinado em cérebro de ratos SOD1G93A demonstrou aumento de trans-hexa-2-enal e trans,trans-hexa-2,4-dienal em fase assintomática e de trans,trans-deca-2,4-dienal em fase sintomática, não sendo observada nenhuma alteração na medula. Conhecer estas variações permite direcionar estudos de modificações em biomoléculas, além de a metodologia per se corroborar com as áreas de análises lipidômicas. Técnicas distintas e o preparo de amostras refletiram nos níveis de glutationa reduzida (GSH) e oxidada (GSSG) relatados. A técnica de espectrometria de massas mostrou-se mais precisa que a detecção eletroquímica; e a alquilação do grupo tiol minimizou interferências de matriz. Por análise de HPLC-UV/Vis-ESI-MS/MS, a quantificação de trans-4-hidroxi-2-nonenal (HNE) e crotonaldeido conjugados com GSH demonstrou não haver alterações em cérebro e medula de ratos SOD1G93A. Contudo, há formação esteroespecífica dos adutos de HNE in vivo. Ressalta-se que a metodologia desenvolvida é extremamente sensível e específica e permite análise simultânea de GSH, GSSG, cisteína, cistina e dos adutos supracitados, servindo para análise de outros adutos de glutationilação de aldeídos que possam ser importantes em doenças associadas a estresse redox. / Free radicais and oxidant species are associated with toxicological and pathophysiological processes. It has been demonstrated that production of reactive oxygen species may be involved in cell signaling and regulation. Several biomarkers of redox processes have been used, including adducts formed through the reaction of &#945;,&#946;-unsaturated aldehydes with biomolecules such as DNA. In order to avoid these deleterious effects, aldehydes are detoxified through glutathionylation and further metabolized to mercapturic derivatives. However, assessing the redox status in biological systems is still a very complex task, and the difficulty in practical and accurate quantification of signaling effects and/or molecular damage is a major problem in redox studies. The objective of this work was to develop accurate and sensitive methods for analysis of potential biomarkers of redox stress, i.e., modified nucleosides, endogenous and exogenous aldehydes, glutathione and glutathionylation products, and their evaluation in cell, animal model and humans. Evaluation of urinary levels of 1,N2-propano-2\'-deoxyguanosine (1,N2-propanodGuo), 1,N2-etheno-2\'-deoxyguanosine and 8-oxo-7,8-dihydro-2\'-deoxyguanosine in residents of São Paulo City - polluted region - showed a significant increase (p<0.05) in 1,N2-propanodGuo levels compared to residents of an unpolluted region by a HPLC-MS/MS methodology developed by the group. Moreover, it was proven, for the first time, that repair deficient cells have basal levels of 1,N2-propanodGuo higher than proficient cells in two independent strains, placing 1,N2-propanodGuo as a potential mediator of carcinogenesis in Fanconi Anemia patients. In an Amyotrophic Lateral Sclerosis (ALS) animal model (SOD1G93A rat) , a 50% increase in the levels of 1,N2-propanodGuo and 100% in the 1,N6-etheno-2\'-deoxyadenosine in brain tissue in the symptomatic phase was observed, suggesting that the high brain lipid content may play a role, leading to impairment of cell metabolism and neuronal cell death. There is an increase of trans-hex-2-enal and trans,trans-hexa-2,4-dienal in asymptomatic SOD1G93A rats brain and of trans,trans-deca-2,4-dienal in symptomatic ones. However, no alteration was observed in spinal cord. Our approach contributes to a better understanding of the aldehyde status in vivo and allows us to predict biomolecule modifications. The developed methodology can contribute to lipidomic studies. The use of different techniques and sample preparation reflected in the reported levels of reduced (GSH) and oxidized glutathione (GSSG). The mass spectrometry technique proved to be more accurate than the electrochemical one, and the use of thiol alkylating agent minimizes matrix interference. No changes were observed in the levels of the GSH conjugates of trans-4-hydroxy-2-nonenal (HNE) and crotonaldehyde in brain and spinal cord of SOD1G93A rats quantified by HPLC-UV/Vis-ESI-MS/MS compared to controls. However, it was observed stereospecific HNE adducts formation in vivo. Note that this methodology is extremely sensitive and specific and allows simultaneous analysis of GSH, GSSG, Cys, cystine and the aforementioned adducts, serving for analysis of other aldehyde-glutathionylation adducts that may be important in pathologies associated with stress redox.
347

Epidemiological and clinical variability of amyotrophic lateral sclerosis between geographic areas and populations : focus on Africa and Latin America / Variabilité épidémiologique et clinique de la sclérose latérale amyotrophique entre les zones géographiques et les populations : focus sur l'Afrique et l'Amérique latine

Luna-Mendez, Jaime-Andres 25 October 2019 (has links)
La sclérose latérale amyotrophique (SLA) est une maladie neurodégénérative fatale. De récents travaux suggèrent une variabilité en termes d'incidence, de mortalité et de caractéristiques cliniques selon les régions géographiques et les populations. Cette thèse offre une mise à jour sur l'hétérogénéité de la SLA, accompagnée de deux études épidémiologiques et cliniques originales en Afrique et en Amérique latine. La première est une étude hospitalière multicentrique dans huit pays africains qui décrit et compare les caractéristiques sociodémographiques et cliniques, les traitements, les facteurs pronostics et la durée de survie chez les patients atteints de la SLA. Certaines caractéristiques sont plus spécifiques aux cas africains par rapport aux occidentaux, telles qu’une proportion plus élevée de patients masculins, un âge de début plus jeune, une proportion plus faible de début bulbaire et une survie plus courte que prévue. Le sous-continent et le traitement par riluzole sont des facteurs indépendamment liés à la survie du patient. La seconde étude en population générale a estimé les taux de mortalité en Équateur, pays composé d’une population majoritairement métisse. Ces résultats soutiennent l’hypothèse d’une survenue plus faible de cas SLA dans les populations métisses d’Amérique latine comparée aux populations caucasiennes d'Europe et d'Amérique du Nord. Les taux de mortalité standardisés ont été comparés entre les groupes ethniques, montrant des différences significatives entre le groupe métisse et le groupe comprenant les autres ethnies (indigènes, asiatiques et arabes). Ce travail fournit des données originales et fiables pour améliorer nos connaissances sur la SLA en Afrique et en Amérique latine. Une collaboration internationale et multidisciplinaire est cruciale pour comprendre la variabilité de la SLA dans différentes populations. / Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disorder with an invariable fatal outcome. Current evidence supports ALS variability in terms of incidence, mortality and clinical features between geographic areas and populations. This dissertation offers an updated review of ALS heterogeneity along with two original epidemiological and clinical studies in Africa and Latin America. First, a multicenter hospital-based study in eight African countries that described and compared the sociodemographic characteristics, clinical features, treatments, prognoses and survival times of patients with ALS. Certain specific characteristics were different in African cases compared to Western cases like higher proportion of male patients, younger age at onset, lower proportion of bulbar onset and shorter survival than expected. Subcontinental location and riluzole treatment are independently associated with survival. Second, a population-based study estimated ALS mortality rates in Ecuador, a predominant admixed population. The findings support a lower ALS occurrence in admixed populations from Latin America compared to European and Northern American populations. Standardized mortality rates were compared among ethnic groups with significant differences between admixed and other ethnic groups (Indigenous, Asians and Arabs). This work provides original and reliable data to improve our knowledge of ALS in Africa and Latin America. An international and multidisciplinary collaboration is crucial to understand ALS variability in different populations.
348

Étude des mécanismes neurophysiologiques de l'instabilité posturale dans la sclérose latérale amyotrophique à partir d'un modèle biomécanique de l'initiation de la marche / Neurophysiological mechanisms study of postural instability in amyotrophic lateral sclerosis from a biomechanical model of gait initiation

Feron, Maryse 16 December 2016 (has links)
L'instabilité posturale est souvent observée chez les patients atteints de la sclérose latérale amyotrophique (SLA). Cependant, les mécanismes neuronaux impliqués dans cette instabilité posturale demeurent largement inconnus. Comparés aux patients SLA sans instabilité postural, les patients atteints de SLA avec instabilité posturale présentent des APA altérés avec un déplacement postérieur du centre de pression du pied diminué (CP) et une durée des APA augmentée, la longueur et la vitesse du premier pas sont réduites, enfin, le contrôle postural dynamique est déficitaire avec une diminution spectaculaire de l'indice de freinage. A l'inverse, nous n’observons aucune modification des phases d’anticipation et d’exécution du pas chez les patients SLA sans instabilité posturale comparés aux sujets témoins. Le faible recul du CP au cours de la phase d’anticipation est corrélé positivement de façon significative à l’atrophie de la substance grise du PCC, SPL, PPN et le CN ; et la durée augmentée de la phase d’anticipation est corrélée négativement de façon significative à l’atrophie de la matière grise du AMS et du cervelet. Les réductions de la vitesse et de la longueur du premier pas sont liées de façon significative à l’atrophie de la matière grise dans le PMC, le PPN et le vermis cérébelleux, enfin, l’absence de freinage actif est corrélée à une diminution du volume de la matière grise du CUN. Ces résultats suggèrent que l'instabilité posturale des patients atteints de SLA est causée, au moins en partie, par le dysfonctionnement des régions et des réseaux connus pour être impliqués dans l'initiation de la marche et dans le contrôle de l’équilibre. / Postural instability is frequently reported in Amyotrophic Lateral Sclerosis (SLA) patients. However, the neural mechanisms that contribute to postural instability in SLA patients remain largely unknown. In comparison to both SLA patients without postural instability and controls, SLA patients with postural instability presented an altered anticipatory postural adjustment (APA) phase with a decreased posterior displacement of the center of foot pressure (CP) and a increased APA duration, decreased length and velocity of the first step and deficit of the dynamic postural control with a dramatic decreased braking index. Conversely, the gait initiation was not significantly modified in SLA patients without postural instability in comparison to controls. The reduced posterior CP displacement during the APA was significantly related to reduced grey matter volume of the left PCC, left SPL, right PPN and caudate nucleus, and the increased APA duration to the reduced grey matter volume of the left AMS and right cerebellum. The reduced velocity of the first step was significantly related to a decreased grey matter volume within the left PMC, right PPN and cerebellar vermis and the reduced braking index to decreased grey matter volume of the right CUN. These results suggest that postural instability of SLA patients result, at least partly, from dysfunction of brain regions and networks known to be involved in gait initiation and balance controls in human.
349

Génération de lignées de poissons-zèbres par génie génétique dans le cadre de l'étude du gène C9orf72

Emond, Alexandre 01 1900 (has links)
No description available.
350

Experiences of pain and associations between pain, disease severity and individual quality of life in people with motor neuron diseases

Åkerblom, Ylva January 2019 (has links)
Many people with the incurable and often times fatal motor neuron diseases have pain, but there is lack of knowledge about people’s experiences of living with pain. Further, the correlation between pain and their quality of life is not well understood, and previous studies have not used individual quality of life, namely that people with their own words express what quality of life is.   The aim of these studies was to explore the experiences of pain and the association between pain and quality of life in people with MND. Methods: Study I was explorative about the individual experience of pain, while study II was correlational between pain, pain severity, disease severity and IQOL. Study I was qualitative, whereas study II used both qualitative and quantitative analysis. Results and conclusions: People with motor neuron diseases experienced pain to have multiple characteristics and impact. However, the results emphasise that the individual experienced some pain characteristics as difficult and that pain could worsen functions that were already affected by the disease. The experience was also that it could be challenging to manage pain. However, the symptom of pain could pass unnoticed in contacts with healthcare professionals (study I). The three most important areas for individual quality of life in both participants with and without pain were: Social relations, followed by Activities for amusement and relaxations, and Being in the outdoor environment. Individual quality of life was noticed to be good regardless of pain. Pain and pain severity were not found to be associated with satisfaction of individual quality of life in patients with motor neuron diseases, neither was disease severity. The results support previous findings, that strong associations between symptoms of MND and IQoL are not obvious. However, this does not infer that pain in people with MNDs should be neglected and undertreated. On the contrary, it seems to be important for healthcare to pay more attention to pain in people with motor neuron diseases and that pain continuously is measured, individually treated and followed. Regardless of whether persons with MND have pain or not, the results point to the importance of healthcare professionals providing support to not only the patient but also the patient’s family and friends, as well as assisting in various forms of relaxing activities and possibility of being in the outdoor environment.

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