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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.
261

Approche physiologiques et pharmacologiques dans un modèle murin de la sclérose latérale amytrophique / Physiological and pharmaceutical approaches in a mouse model of amyotrophic lateral sclerosis

Gerber, Yannick 13 December 2011 (has links)
La sclérose latérale amyotrophique (SLA) est une maladie neurodégénérative caractérisée par une mort sélective des motoneurones. Les mécanismes impliqués dans cette pathologie sont encore mal connus. Il apparait néanmoins que la SLA est une maladie multifactorielle impliquant différents partenaires tels que les motoneurones, les cellules gliales et musculaires. Le modèle murin SOD1G93A développe un phénotype semblable à celui observé chez les patients SLA. L'étude précise du patron locomoteur des SOD1G93A nous a permis de re-définir la date d'apparition des symptômes à 2 mois d'âge soit 1 un mois avant la date communément admise. Nous corrélons cette donnée fonctionnelle à des modifications histologiques au niveau médullaire, en particulier sur la composante gliale, et musculaire. Sur cette base, nous avons développé deux approches in vivo, l'une physiologique et l'autre pharmacologique. D'une part nous avons caractérisé les effets d'exercices physiques de différentes intensités chez les souris SOD1G93A. Cette étude à mis en évidence le rôle primordial de l'environnement et ne démontre pas d'effet de l'exercice sur la survie des souris SOD1G93A. D'autre part, nous rapportons une augmentation de survie des souris SOD1G93A après traitement chronique à faible dose d'une molécule anti-glutamatergique, la gacyclidine. A forte dose cette molécule semble avoir un effet néfaste.En parallèle, nous avons décrit la répartition anatomique de la sérotonine et d'un de ses récepteurs dans la moelle épinière humaine. Nous observons de grandes similarités topographiques avec les murins et primates, et validons ainsi l'utilisation future de ces modèles animaux dans les pathologies affectant la locomotion tel que la SLA. / Amytrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by a selective death of motoneurons. Pathogenesis and mechanisms of selective vulnerability are not yet fully understood although there is growing evidences that ALS is a complex multi-factorial disease that involves several partners such as neuron, glial and muscle cells. Transgenic mice over-expressing a human mutated form of the gene coding for SOD1 develop a dominantly inherited adult-onset paralytic disorder that mimics human ALS symptoms. The precise description of the SOD1G93A mice locomotor pattern using a gait analysis method allowed us to refine symptoms onset at two months of age. This is one month earlier than described in the literature. We correlate these functional modifications to histological alterations of (1) the glial component of the spinal cord, and (2) muscles. From this referent study, we have then developed and evaluated a physiological and pharmacological in vivo approaches. In our first study, we have characterized the effect of different intensities of physical exercise on SOD1G93A mice. Our study not only demonstrates the crucial role of the environment but also that exercise does not have an impact on the survival of SOD1G93A mice. In the second part of our work, we report an increase in SOD1G93A mice survival when they had been chronically treated with a low dose of gacyclidine, an anti-glutamatergic molecule. At higher dose, this molecule seems to be detrimental.In a parallel study, we have carried out the anatomical description of serotonin and one of its receptor in the adult human spinal cord. We observe topographic similarities with rodents and primates, thus validating their further use as animal models, to study motor pathologies such as ALS.
262

Från Anhörig till Vårdare : En kvalitativ litteraturstudie om att vårda en närstående med ALS / From family member to family carer : A qualitative literature study about caring for a relative with ALS

Holmquist, Rebecka, Andersson, Simon January 2020 (has links)
Bakgrund: Amyotrofisk lateralskleros (ALS) är progredierande sjukdom som drabbar nervcellerna vilka styr muskulaturen med koldioxidnarkos vilket är den vanligast dödsorsaken inom tre till fem år. Det är vanligt att anhöriga agerar vårdare till den sjuke vilket kan leda till ökad stress och börda för anhörigvårdaren.   Syfte: Syftet var att beskriva anhörigvårdares upplevelser av att vårda närstående med ALS.Metod:Kvalitativ litteraturstudie av tio vetenskapliga artiklar från databaserna; PubMed, CINAHL, PsyHub, Web of Science som analyserades utifrån Fribergs femstegsmodell.  Resultat: Tre huvudteman identifierades samt ten subteman. Framtagna huvudteman var; Omvälvande Känslor, Att förändras i sin roll samt Strategier för att orka. Slutsats: Anhörigvårdare till närstående med ALS upplevde ständigt nya problem, ökad börda och fler uppoffringar. Förhållandet till den sjuke förändrades när relationen gick från anhörig till vårdare och känslan av normalitet blev svår att upprätthålla. Upplevelserna av extern vårdpersonal var splittrad med både goda och sämre erfarenheter. Familjecentrerat förhållningsätt bör användas inom vården för att anhörigvårdares behov ska mötas. / Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative neuromuscular disease affecting the motor neurons with eventual death due to respiratory failure within three to five years. It is common for family members or friends to nurse patients which can lead to increased stress and burden for the family carers.   Aim: The aim of this study was to describe family carers experiences of caring for a relative with ALS.Methods:Qualitative literature study of ten scientific papers taken from four databases; “PubMed”, “CINAHL”, PsyHub” and “Web of Science”. These were analysed using Fribergs five step model. Results: 3 main themes were identified alongside 10 subthemes. The main themes consisted of; Turbulent Emotions, The change in one’s role, Strategies to manage.  Conclusion: Family carers with relatives inflicted with ALS experienced increased burden of new responsibilities, increased strain, and forfeiture of one’s normality. The relationship with the afflicted individual changed from family member/friend to carer. Family carers found that the quality of care given by external care staff was inconsistent. Family focus care needs to be more prevalent to meet the needs of family carers.
263

Brain-Computer Interface (Bci) Evaluation in People With Amyotrophic Lateral Sclerosis

McCane, Lynn M., Sellers, Eric W., Mcfarland, Dennis J., Mak, Joseph N., Carmack, C. Steve, Zeitlin, Debra, Wolpaw, Jonathan R., Vaughan, Theresa M. 01 January 2014 (has links)
Brain-computer interfaces (BCIs) might restore communication to people severely disabled by amyotrophic lateral sclerosis (ALS) or other disorders. We sought to: 1) define a protocol for determining whether a person with ALS can use a visual P300-based BCI; 2) determine what proportion of this population can use the BCI; and 3) identify factors affecting BCI performance. Twenty-five individuals with ALS completed an evaluation protocol using a standard 6 × 6 matrix and parameters selected by stepwise linear discrimination. With an 8-channel EEG montage, the subjects fell into two groups in BCI accuracy (chance accuracy 3%). Seventeen averaged 92 (± 3)% (range 71-100%), which is adequate for communication (G70 group). Eight averaged 12 (± 6)% (range 0-36%), inadequate for communication (L40 subject group). Performance did not correlate with disability: 11/17 (65%) of G70 subjects were severely disabled (i.e. ALSFRS-R < 5). All L40 subjects had visual impairments (e.g. nystagmus, diplopia, ptosis). P300 was larger and more anterior in G70 subjects. A 16-channel montage did not significantly improve accuracy. In conclusion, most people severely disabled by ALS could use a visual P300-based BCI for communication. In those who could not, visual impairment was the principal obstacle. For these individuals, auditory P300-based BCIs might be effective.
264

RNAi Knockdown of Par-4 Inhibits Neurosynaptic Degeneration in ALS-Linked Mice

Xie, Jun, Awad, Keytam S., Guo, Qing 01 January 2005 (has links)
Evidence from human amyotrophic lateral sclerosis (ALS) patients and ALS-linked Cu/Zn superoxide dismutase (Cu/Zn-SOD) transgenic mice bearing the mutation of glycine to alanine at position 93 (G93A) suggests that the pro-apoptotic protein prostate apoptosis response-4 (Par-4) might be a critical link in the chain of events leading to motor neuron degeneration. We now report that Par-4 is enriched in synaptosomes and post-synaptic density from the ventral horn of the spinal cord. Levels of Par-4 in synaptic compartments increased significantly during rapid and slow declining stages of muscle strength in hSOD1 G93A mutant mice. In the pre-muscle weakness stage, hSOD1 G93A mutation sensitized synaptosomes from the ventral horn of the spinal cord to increased levels of Par-4 expression following excitotoxic and apoptotic insults. In ventral spinal synaptosomes, Par-4-mediated production of pro-apoptotic cytosolic factor(s) was significantly enhanced by the hSOD1 G93A mutation. RNA interference (RNAi) knockdown of Par-4 inhibited mitochondrial dysfunction and caspase-3 activation induced by G93A mutation in synaptosomes from the ventral horn of the spinal cord, and protected spinal motor neurons from apoptosis. These results identify the synapse as a crucial cellular site for the cell death promoting actions of Par-4 in motor neurons, and suggest that targeted inhibition of Par-4 by RNAi may prove to be a neuroprotective strategy for motor neuron degeneration.
265

Identification of Novel Genetic Variations for Amyotrophic Lateral Sclerosis (ALS)

Xu, Guang 27 February 2018 (has links)
A list of genes have been identified to carry mutations causing familial ALS such as SOD1, TARDBP, C9orf72. But for sporadic ALS, which is 90% of all ALS cases, the underlying genetic variants are still largely unknown. There are multiple genome-wide association study (GWAS) for sporadic ALS, but usually a large number nominated SNP can hardly be replicated in larger cohort analysis. Also majority of GWAS SNP lie within noncoding region of genome, imposing a huge challenge to study their biological role in ALS pathology. With the rapid development of next-generation sequencing technology, we are able to sequence exome and whole-genome of a large number of ALS patients to search for novel genetic variants and their potential biological function. Here by analyzing exam data, we discovered two novel or extremely rare missense mutations of DPP6 from a Mestizo Mexican ALS family. We showed the two mutations could exert loss-of-function effect by affecting electrophysiological properties of Potassium channels as well as the membrane localization of DPP6. To our knowledge this is the first report of DPP6 nonsynonymous mutations in familial ALS patients. In addition, by analyzing whole-genome data, we discovered strong linkage disequilibrium between SNP rs12608932, a repeatedly significant ALS GWAS signal, and one polymorphic TGGA tetra-nucleotide tandem repeat, which is further flanked by large TGGA repetitive sequences. We also demonstrated rs12608932 risk allele is associated with reduced UNC13A expression level in human cerebellum and UNC13A knockout could lead to shorter survival in SOD1-G93A ALS mice. Thus the TGGA repeat might be the real underlying genetic variation that confer risk to sporadic ALS.
266

Functional Characterization of Novel PFN1 Mutations Causative for Familial Amyotrophic Lateral Sclerosis: A Dissertation

Wu, Chi-Hong 17 December 2015 (has links)
Amyotrophic lateral sclerosis (ALS) is a progressive adult neurodegenerative disease that causes death of both upper and lower motor neurons. Approximately 90 percent of ALS cases are sporadic (SALS), and 10 percent are inherited (FALS). Mutations in the PFN1 gene have been identified as causative for one percent of FALS. PFN1 is a small actin-binding protein that promotes actin polymerization, but how ALS-linked PFN1 mutations affect its cognate functions or acquire gain-of-function toxicity remains largely unknown. To elucidate the contribution of ALS-linked PFN1 mutations to neurodegeneration, we have characterized these mutants in both mammalian cultured cells and Drosophila models. In mammalian neuronal cells, we demonstrate that ALS-linked PFN1 mutants form ubiquitinated aggregates and alter neuronal morphology. We also show that ALS-linked PFN1 mutants have partial loss-of-function effects on actin polymerization in growth cones of mouse primary motor neurons and larval neuromuscular junctions (NMJ) in Drosophila. In Drosophila, we also observe that PFN1 level influences integrity of adult motor neurons, as demonstrated by locomotion, lifespan, and leg NMJ morphology. In sum, the work presented in this dissertation has shed light on PFN1- linked ALS pathogenesis by demonstrating a loss-of-function mechanism. We have also developed a Drosophila PFN1 model that will serve as a valuable tool to further uncover PFN1-associated cellular pathways that mediate motor neuron functions.
267

ALS-induced Excitability Changes in Individual Motorneurons and the Spinal Motorneuron Network in SOD1-G93A Mice at Symptom Onset

Draper, Christiana S.I. 19 May 2021 (has links)
No description available.
268

The effect of air pollution on aggravation of neurodegenerative diseases: an analysis of long-term exposure to fine particulate matter and its components

Nunez, Yanelli January 2020 (has links)
Background: Air pollution is one of the leading environmental issues in the world today. In 2015, pollution-related diseases accounted for 16% of all deaths worldwide — that is an estimated 9 million premature deaths were linked to air pollution. In addition to the substantial effects on human health, air pollution-related diseases result in productivity losses that reduce countries’ gross domestic product. Although air pollution disproportionately affects middle- and low-income countries, it is still a major issue in high-income countries, such as the United States, where 25% of Americans breath air with pollutant levels above the national regulatory standards. Fine particle matter (particles with diameter ≤ 2.5 μm, PM₂.₅ ) is the most extensively studied air pollutant and it has been causally linked with a wide range of adverse health outcomes, including cardiovascular and pulmonary disease, myocardial infarction, hypertension, congestive heart failure, arrhythmias, chronic obstructive pulmonary disease, and lung cancer. Moreover, recent scientific evidence suggests that PM₂.₅ affects the nervous system and possibly contributes to the development and exacerbation of neurodegenerative diseases. This is increasingly relevant as populations are aging and the number of adults living with neurodegenerative diseases increases, negatively affecting families, communities, and health-care systems around the world. Although millions of people suffer from neurodegenerative diseases, there is currently no treatment that slows the progression of these conditions and no known cure or cause. Thus, determining whether a link exists between air pollution and neurodegenerative diseases is a goal of increasing importance. Objective: The research presented in this dissertation has two main objectives: (1) to characterize the relationship between long-term exposure to PM₂.₅ and disease aggravation in two of the most prevalent neurodegenerative diseases worldwide: Alzheimer’s (AD) and Parkinson’s disease (PD), as well as in the rare and devastating neurodegenerative motor disorder amyotrophic lateral sclerosis (ALS); (2) to identify the specific PM₂.₅ chemical components that are associated with disease aggravation in PD. Methods: We used data from the New York Department of Health Statewide Planning and Research Cooperative System from 2000–2014 to identify patients’ first hospitalization with a primary or secondary diagnosis of AD, PD, or ALS. With these data, we constructed annual AD, PD, and ALS first hospitalization county counts (total and sex- and age-stratified) for all of New York State (NYS). A patient’s first hospital admission was used as a surrogate for disease aggravation, indicating the crossing point into a more severe stage of the disease. We used prediction estimates from well-validated models that incorporate satellite information and ground-based monitoring data to estimate annual PM₂.₅ and PM₂.₅ chemical component (nitrate, sulfate, organic matter, sea salt, black carbon, and soil) concentrations across NYS at a high spatial resolution. In Chapter 2, we used outcome-specific (AD, PD, or ALS) mixed quasi-Poisson models with county-specific random intercepts to assess the relationship between long-term exposure to PM₂.₅ and disease aggravation. In Chapter 3, we used a multi-pollutant mixed quasi-Poisson model with county-specific random intercepts to identify specific PM₂.₅ components associated with disease aggravation in PD. In all analyses, we evaluated potential nonlinear exposure–outcome relationships using penalized splines and accounted for potential confounders. Results: We observed a total of 264,075 AD, 114,514 PD, and 5,569 ALS first admissions between 2000 and 2014. The hospitalization annual average counts per county were 284, 131, and 6 for AD, PD, and ALS, respectively. In Chapter 2, we found a nonlinear association between total PM₂.₅ exposure and PD hospitalizations, which plateaued at higher concentrations of PM₂.₅ (> 13 μg/m³, RR=1.08, 95% CI: 1.04–1.13 for a PM₂.₅ increase from 8 to 10 μg/m³, Figure 2.3). We also found that patients with a first PD hospitalization at age 70 or younger are at slightly higher risk for disease aggravation at lower PM₂.₅ concentrations relative to those age >70. In the case of AD, we observed evidence of a potential association between annual increases in PM₂.₅ exposure and disease aggravation, but only in a sensitivity analysis aiming to decrease outcome misclassification. We found no association for ALS in the main analysis, but we observed an unexpected negative association in those <70 years in the stratified analysis. We found no evidence of effect modification by sex for any of the outcomes. In Chapter 3, we observed a linear association between disease aggravation in PD and long-term exposure to the PM₂.₅ components nitrate (RR = 1.05, 95%CI: 1.02–1.09 per one standard deviation (SD) increase) and organic matter (RR = 1.05, 95%CI: 1.02– 1.07 per one SD increase), and a nonlinear association for black carbon with a negative association above the 96th percentile of the BC concentration distribution (Figure 3.4). We found no evidence of an association with sulfate, sea salt or soil. Conclusion: Overall, our studies provide an analysis of the potential association between long-term exposure to PM₂.₅ , both as an overall pollution mixture and by chem- ical composition, and disease aggravation in AD, PD, and ALS. Our findings suggest that annual increases in county-level PM₂.₅ concentrations are associated with disease aggravation in PD and possibly AD. We found that the PM₂.₅ components organic matter and nitrate are particularly harmful in the association between PM₂.₅ and dis- ease aggravation in PD. Additionally, our results indicate that current national PM₂.₅ standards may not be strict enough to safeguard the population’s neurological health. Specifically, in Chapter 2, we observed that the PM₂.₅ –PD association has a steeper slope at lower concentrations that are well below the current annual National Ambient Air Quality Standards for PM₂.₅ . Thus, our findings warrant further investigation into the potential link between long-term PM₂.₅ exposure and disease aggravation, particularly in the context of PD. Our results also indicate that the chemical composition of PM2.5 affects its neurotoxicity. Further research into how PM₂.₅ composition influences the overall PM₂.₅ adverse effects is needed to fully understand the mechanisms that underlie the association between exposure to PM₂.₅ and aggravation of neurodegenerative diseases.
269

Development of solution NMR method for observation and analysis of proteins inside cells / 核磁気共鳴法による細胞内タンパク質の観測及び手法開発

Murayama, Shuuhei 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19003号 / 工博第4045号 / 新制||工||1622(附属図書館) / 31954 / 京都大学大学院工学研究科分子工学専攻 / (主査)教授 白川 昌宏, 教授 佐藤 啓文, 教授 梶 弘典 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
270

Patienters upplevelse av att leva med ALS : en litteraturöversikt / Patient's experience of living with ALS : a literature review

Cic, Ella, Kulmala, Camilla January 2020 (has links)
Bakgrund: ALS är en obotlig neurologisk sjukdom som leder till försvagning av muskler efter en nedbrytande process i nervsystemet. Det finns en ärftlig komponent, men i många fall går det inte att fastställa orsaken bakom sjukdomens uppkomst. Att diagnostiseras med en obotlig sjukdom där kroppsliga funktioner avtar samtidigt som de kognitiva förmågorna och känseln består innebär ofta ett stort lidande för patienterna. Att beskriva patienters erfarenheter av sjukdomen kan öka förståelsen och skapa en möjlighet att närma sig lidandet. Syfte: Syftet var att beskriva patienters upplevelse av att leva med ALS. Metod: Studien är en litteraturöversikt som baserades på 15 vetenskapliga artiklar. Dessa återfanns i databaserna Pubmed och CINAHL. Artiklarna granskades med hjälp av Sophiahemmets Högskolas formulär för kvalitetsgranskning och analyserades genom en integrerad analys. Resultat: Ur analysen framträdde tre kategorier: “Upplevelsen av maktlöshet”, “Upplevelsen av att vara en börda” och “Upplevelsen av att anpassa sig till en ny tillvaro”. I resultatet framkom att patienter med ALS upplevde ett lidande som de själva beskrev i olika termer, men likaså återgav de positiva erfarenheter och hur dem utvecklade strategier för att hantera sin nya tillvaro. Slutsats: Denna litteraturöversikt beskriver hur patienter med ALS hanterar sin verklighet, vilket till viss del skiljer sig åt. Lidandet som patienterna upplever kan bli del av personlig utveckling, samtidigt som risken finns att hela livsperspektivet påverkas negativt om patienterna fastnar i lidandet. Sjuksköterskan har en viktig roll i att lindra patienters lidande och litteraturöversikten upplyser om hur ett personcentrerat förhållningssätt, som bland annat innefattar lyhördhet till hur patienterna upplever sin tillvaro, kan bidra till detta. / Background: ALS is an incurable neurological disease that leads to muscle deterioration following a degrading process in the nervous system. There is a hereditary component, but in many cases it is not possible to determine the cause behind the onset of the disease. Being diagnosed with an incurable disease in which bodily functions decline at the same time as the cognitive abilities and tactile sense remains often results in great suffering for the patients. Describing patients' experiences of the disease can increase understanding and create an opportunity to approach suffering. Aim: The aim was to describe patients' experiences of living with ALS. Method: The study is a literature review based on 15 articles. These were found in the databases PubMed and CINAHL. The articles were reviewed with the use of Sophiahemmets Högskola's form for quality review and were analyzed through integrated analysis. Results: From the analysis three categories appeared: “The experience of powerlessness”, “The experience of being a burden” and “The experience of adapting to a new existence”. The results showed that patients with ALS experienced suffering that they themselves described in different terms, but they also portrayed positive experiences and how they developed strategies to manage their new situation. Conclusions: This literature review describes how patients with ALS manage their reality, which differs to some extent. The suffering that the patients experience may be part of personal development, while there is a risk that the entire life perspective will be adversely affected if the patients become stuck in the suffering. The nurse plays an important role in relieving patients suffering and the literature review informs how a person-centered approach, which includes, among other things, responsiveness to how patients experience their lives, can contribute to this.

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