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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.
201

Relationship Between Intelligibility and Response Accuracy of the Amazon Echo in Individuals with Amyotrophic Lateral Sclerosis Exhibiting Mild-Moderate Dysarthria

Layden, Caroline A. 27 June 2018 (has links)
There is an ever-growing and increasing amount of technology options that use speech recognition software. Currently, the market includes smartphones, computers, and individual smart home personal assistants that allow for hands-free access to this technology. Research studies have explored the utility of these assistive devices for the completion of activities of daily living; however, there is limited research looking at the accuracy of voice recognition software within smart home personal assistants in populations with disordered speech. In persons with amyotrophic lateral sclerosis (ALS), symptoms include changes to motor functions, speech in particular, and it is unknown how some of these devices may respond to their disordered speech. The present study aimed to examine the accuracy of the Amazon Echo to respond appropriately to commands given by dysarthric patients with ALS. Participants were asked to read a variety of commands to an Amazon Echo. The sentences and responses by the Amazon Echo were audio-recorded for transcription and intelligibility ratings, which were then analyzed to look for relationships between intelligibility, auditory-perceptual features of speech, and sentence type. Results revealed there was no significant relationship between command intelligibility and accuracy of response by the Amazon Echo, nor was there a significant relationship between any of the auditory-perceptual ratings and accuracy of response. There was, however, a significant and positive association between conversational intelligibility and accuracy of responses by the Amazon Echo. This study provides support for use of hands-free assistive technology in patients with ALS to aid in the maintenance of quality of life and activities of daily living.
202

Finding new genes causing motor neuron diseases

Gopinath, Sumana January 2007 (has links)
Doctor of Philosophy / Abstract Neurodegenerative disorders are a diverse group of disorders that affect specific subsets of neurons. Motor neuron diseases, neurodegenerative disorders of motor neurons, are seen commonly as sporadic cases and less frequently as familial disease forms. The familial forms show genetic and phenotypic heterogeneity. Clinically motor neuron diseases may be seen as rapidly progressive disorders like amyotrophic lateral sclerosis, ALS or slowly progressive disorders like hereditary motor neuropathies, HMN. The only proven causes for motor neuron diseases are gene mutations that lead to motor neuron degeneration in familial disease forms. Only some of these genes have been identified and have contributed greatly to our understanding of the neurobiology of familial and sporadic disease forms. Identification of additional disease causing genes would help enhance our knowledge of the pathophysiological mechanisms underlying all forms of motor neuron disorders, which would lead to early diagnoses, effective prophylaxis and efficient therapies for these disorders. This study aimed to find gene mutations that cause rapid and slowly progressive familial motor neuron disorders in Australian families and to determine their relevance to sporadic forms of motor neuron disease. The familial forms of ALS show reduced disease penetrance, that is, not all gene mutation carriers manifest the disease. This study examines ALS penetrance in a group of Australian families. The most frequently observed mutations in ALS families are cytosolic superoxide dismutase/SOD1 gene mutations. In a collection of ALS families in our centre, families without the common SOD1 gene mutations were genotyped for other ALS genes and loci and studied using genetic linkage and haplotype analyses. Studies in a large Australian ALS family further confirmed genetic heterogeneity in non-SOD familial ALS, all known autosomal dominant ALS genes and chromosomal loci were excluded as cause of disease in this family. Such families can be studied further to identify additional disease genes and loci mapped in other ALS families. These families represent powerful resources for identification of additional ALS genes. Identifying the pathogenic genes in families with reduced disease penetrance may be more relevant to sporadic forms of disease. dHMN is a chronic neurodegenerative disorder predominantly affecting motor neurons. In a large Australian dHMN family, all the known dHMN genes and chromosomal loci were excluded as cause of disease. A genome wide microsatellite screen was performed in this family and genetic linkage was established to a novel 12.98 Mb locus on chromosome 7q34.2-q36. Candidate genes in this large interval will be screened based on their function and expression profile. Identification of a new dHMN locus provides the basis for future identification of a novel gene involved in motor neuron degeneration. Genes in dHMN have been shown to be pathogenic in ALS and Charcot Marie Tooth syndromes. The new locus for dHMN mapped in this project would lead to identification of a novel dHMN gene, which may elucidate the pathogenesis underlying a wide range of neurodegenerative disorders.
203

Alternativ splicing i mänsklig sjukdom

Edin, Joel January 2010 (has links)
<p>Exoner är de sekvenser i DNA vilka rymmer koden för proteiner i människan och i alla andra organismer. Intronerna, vilka utgör utrymmet mellan exoner, består av ickekodande sekvenser och kontrollelement. Exoner tillhörande en gen måste inte alltid inkluderas i den slutliga mRNA produkten, alternativ splicing tillåter exkludering av vissa sekvenser och gör att en gen kan ha mer än en mRNA produkt, därigenom kan en gen koda för flera olika proteiner. Alternativ splicing är ett fält som snabbt utvecklas och dess relevans för många sjukdomar har blivit uppenbar. Detta arbete går igenom ett flertal av dessa sjukdomar för att sammanställa ny forskning och tydliggöra rollen av alternativ splicing i dem. De sjukdomar som undersökts är cystisk fibros, ärftlig frontotemporal dementia, systemisk lupus erythematosus, aniridi, myotonisk dystrofi, amyotrophic lateral sclerosoch familial dysautonomia. Dessa sjukdomar har involvering av alternativ splicing, de genetiska processerna bakom dem är dock mycket olika och kan visa på de många sätt alternativ splicing kan påverka cell och kroppsfunktion. Målet med arbetet är en översiktlig bild av framstegen som gjorts och vilken forskning som nu bedrivs.</p>
204

ALS – a Clinical Thesis

Nygren, Ingela January 2005 (has links)
<p>Amyotrophic lateral sclerosis (ALS) is characterized by a progressive loss of upper and lower motor neurons, resulting in muscle weakness and death from respiratory failure within 3-5 years after onset. The incidence is 1.5-2.7/100,000 inhabitants. 5-10% of all cases are hereditary. The aetiology of sporadic ALS is still unknown. </p><p>The only neuroprotective drug approved for the treatment of ALS is riluzole, a glutamate-antagonist, which has shown to improve survival. We evaluated if riluzole sales statistics can be used as a method for estimating the prevalence of ALS/motor neuron disease in Sweden. We found that this method, which is less time consuming than conventional methods, could be used as a crude marker for the prevalence. </p><p>In a longitudinal study of overall Quality of Life (QoL) in ALS we found that QoL changes only slightly over time despite disease progression. ALS does not necessarily result in a low QoL. </p><p>Growth factors are important for the survival of neurons. In ALS we found increased or normal levels of GDNF mRNA and BDNF mRNA in muscle biopsies, VEGF in serum and spinal cord and FGF-2 in serum and cerebrospinal fluid. There is thus no deficit of these growth factors although there may be a relative lack because of high demands of the motor neurons. Polyamines are small aliphatic molecules that are important for the function of cells. The level of the polyamines spermidine and spermine were increased in red blood cells in both patients with ALS and patients with Parkinson’s disease, suggesting that polyamines may have a role for the neurodegenerative process. Polyamines in spinal cord were of the same level in the patients with ALS and in controls, indicating a maintained regulation of polyamines at the end-stage of the disease.</p>
205

Amyotrophic Lateral Sclerosis – A Study in Transgenic Mice

Wootz, Hanna January 2006 (has links)
<p>Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with an incidence of 1.5-2.7/100000 people/year. Today there is no cure for the disease and only symptomatic treatments are available. ALS progresses rapidly and only 50% of the patients are alive three years after the symptom debut. In ALS, the upper and lower motor neurons undergo degeneration in a process resembling apoptosis. This leads to muscle atrophy and paralysis. The causes of neuronal death are however unknown. In this thesis we have studied transgenic mice carrying human mutant superoxide dismutase, as a model for familial ALS. These mice develop ALS-like symptoms after four months of age with degeneration of the motor neurons. Our results show an involvement of endoplasmic reticulum stress, caspase-12, -9, -3 and procaspase-7 in the ALS mice spinal cord. Overexpression of the antiapoptotic protein XIAP in spinal cord neurons inhibited the activation of caspase-12 and reduced caspase-3 and calpain activity. Calpastatin, the regulator of calpain activity, was kept intact in the ALS-XIAP mice. These mice showed a 12% increase in the mean survival suggesting a beneficial effect of XIAP in ALS. The reason for the ultimate cell death of motor neurons in the ALS-XIAP mice may be due to the activation of additional cell death pathways. Thus, we observed that lysosomal proteases particularly, cathepsinB, -D, and -L were activated in the ALS mice spinal cord together with a less marked upregulation of the inhibitors, cystatinB and -C. We also found activation of astrocytes and microglial cells in the spinal cord of ALS mice indicating their involvement in the disease. The results show that both caspase-dependent and -independent pathways are activated during neuronal degeneration in the ALS spinal cord. The results obtained may help to identify novel drug targets for future treatments of ALS.</p>
206

ALS – a Clinical Thesis

Nygren, Ingela January 2005 (has links)
Amyotrophic lateral sclerosis (ALS) is characterized by a progressive loss of upper and lower motor neurons, resulting in muscle weakness and death from respiratory failure within 3-5 years after onset. The incidence is 1.5-2.7/100,000 inhabitants. 5-10% of all cases are hereditary. The aetiology of sporadic ALS is still unknown. The only neuroprotective drug approved for the treatment of ALS is riluzole, a glutamate-antagonist, which has shown to improve survival. We evaluated if riluzole sales statistics can be used as a method for estimating the prevalence of ALS/motor neuron disease in Sweden. We found that this method, which is less time consuming than conventional methods, could be used as a crude marker for the prevalence. In a longitudinal study of overall Quality of Life (QoL) in ALS we found that QoL changes only slightly over time despite disease progression. ALS does not necessarily result in a low QoL. Growth factors are important for the survival of neurons. In ALS we found increased or normal levels of GDNF mRNA and BDNF mRNA in muscle biopsies, VEGF in serum and spinal cord and FGF-2 in serum and cerebrospinal fluid. There is thus no deficit of these growth factors although there may be a relative lack because of high demands of the motor neurons. Polyamines are small aliphatic molecules that are important for the function of cells. The level of the polyamines spermidine and spermine were increased in red blood cells in both patients with ALS and patients with Parkinson’s disease, suggesting that polyamines may have a role for the neurodegenerative process. Polyamines in spinal cord were of the same level in the patients with ALS and in controls, indicating a maintained regulation of polyamines at the end-stage of the disease.
207

Amyotrophic Lateral Sclerosis – A Study in Transgenic Mice

Wootz, Hanna January 2006 (has links)
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with an incidence of 1.5-2.7/100000 people/year. Today there is no cure for the disease and only symptomatic treatments are available. ALS progresses rapidly and only 50% of the patients are alive three years after the symptom debut. In ALS, the upper and lower motor neurons undergo degeneration in a process resembling apoptosis. This leads to muscle atrophy and paralysis. The causes of neuronal death are however unknown. In this thesis we have studied transgenic mice carrying human mutant superoxide dismutase, as a model for familial ALS. These mice develop ALS-like symptoms after four months of age with degeneration of the motor neurons. Our results show an involvement of endoplasmic reticulum stress, caspase-12, -9, -3 and procaspase-7 in the ALS mice spinal cord. Overexpression of the antiapoptotic protein XIAP in spinal cord neurons inhibited the activation of caspase-12 and reduced caspase-3 and calpain activity. Calpastatin, the regulator of calpain activity, was kept intact in the ALS-XIAP mice. These mice showed a 12% increase in the mean survival suggesting a beneficial effect of XIAP in ALS. The reason for the ultimate cell death of motor neurons in the ALS-XIAP mice may be due to the activation of additional cell death pathways. Thus, we observed that lysosomal proteases particularly, cathepsinB, -D, and -L were activated in the ALS mice spinal cord together with a less marked upregulation of the inhibitors, cystatinB and -C. We also found activation of astrocytes and microglial cells in the spinal cord of ALS mice indicating their involvement in the disease. The results show that both caspase-dependent and -independent pathways are activated during neuronal degeneration in the ALS spinal cord. The results obtained may help to identify novel drug targets for future treatments of ALS.
208

紀錄片:看天花板的人 / Documentary:The ALS:The Choice

陳明輝, Chen, Ming Hui Unknown Date (has links)
「如果說人生是一列火車,每個人手上都有一張沒有標明終點站的車票,那麼沿路的每個站名對我們而言,都不重要,但是當終點站名出現時,你要怎麼面對下一站 。」 人生列車上,有你有我。只是我們都不知道彼此的終點站。有些人的終點來得很突然,有些人卻老早就知道自己即將在不遠的下一站下車。漸凍人就是如此。 每個漸凍人都有一條專屬於自己的病歷曲線,雖然每條線長相不同,但在曲線長尾都會面對同一件事-氣切。不願氣切的漸凍人可能隨時面臨列車靠站,被生命列車長趕下車的命運。即使願意氣切,許多漸凍人仍面臨下一站到站的威脅。 「看天花板的人」是三個忙碌漸凍人的故事。為何說他們忙碌?因為他們深怕沒有明天,因為他們害怕深夜的一口痰就把他們噎死。於是他們過得比誰都忙碌。 當社會上不時傳來貧瘠過活、甚至輕易了斷生命的新聞時,有一群隨時會被趕下生命列車的漸凍人,卻豐富每天的生命。當太陽照例從東邊升起時,他們嘴邊總是泛著笑意,「我又賺到一天了。」 但是病歷總會有走到曲線長尾的一天,面對呼吸中止的威脅,到底要不要氣切,要不要成為「看天花板的人」,這樣的抉擇,卻比度過漫漫長夜還要令人煎熬。 關鍵詞:紀錄片、生命教育、漸凍人、ALS、氣切
209

Of mice and men : SOD1 associated human amyotrophic lateral sclerosis and transgenic mouse models

Graffmo, Karin Sixtensdotter January 2007 (has links)
Amyotrophic lateral sclerosis, ALS, is a progressive fatal neurodegenerative disorder affecting motor neurones in motor cortex, brain stem and spinal cord. This inevitably leads to paralysis, respiratory failure and death. In about 5% of patients with ALS there is an association with mutations in gene for the abundant intracellular scavenging enzyme superoxide dismutase1, SOD1. The noxious property of SOD1 is proposed to be due to gain of function. In familial cases the inheritance is most commonly dominant. This study focus on two disparate SOD1 mutations occurring in Scandinavia. The recessive D90A mutation which has properties similar to that of the normal wild-type human SOD1. The dominantly inherited G127insTGGG mutation, G127X, causes a C-terminal truncation of the last 21 amino acids and is a highly unstable protein. Transgenic mice were created expressing D90A and G127X mutated human SOD1. Results from studies of tissue from the central nervous system of patients carrying either of these mutations were compared with similar tissue collected from transgenic mice generated with the same mutations. Tissue from the mice were also compared to central nervous tissue from several other transgenic mouse strains expressing human wild type SOD1 as well as other ALS associated human SOD1 mutations. The transgenic mice expressing D90A respectively G127X mutated human SOD1 develop motor neurone disease. Microscopic studies of central nervous tissues from G127X transgenic mice reveals inclusions of aggregated misfolded SOD1 in motor neurones and adjacent supporting cells. These inclusions are composed of detergent resistant aggregates and preceded by accumulations of minute quantities of detergent-soluble aggregates. The inclusions mimic those found in G127X patients. In D90A transgenic mice the progression, as in the humans, was slower and the mice, as the patients, showed bladder disturbance. In the D90A patients, the SOD1 inclusions mimic those found in sporadic ALS patients. Aggregation of SOD1 in central nervous tissue appears to be related to severity of disease. Degenerative features as vacuolization and gliosis precedes phenotypic alterations. Changes are seen not only in motor areas but also in higher centres of the telencephalon.
210

SOD1´s Law : An Investigation of ALS Provoking Properties in SOD1

Byström, Roberth January 2009 (has links)
Proteins are the most important molecules in the cell since they take care of most of the biological functions which resemble life. To ensure that everything is working properly the cell has a rigorous control system to monitor the proper function of its proteins and sends old or dysfunctional proteins for degradation. Unfortunately, this system sometimes fails and the once so vital proteins start to misbehave or to accumulate and in the worst case scenario these undesired processes cause the death of their host. One example is Amyotrophic Lateral Sclerosis (ALS); a progressive and always fatal neurodegenerative disorder that is proposed to derive from accumulation of aberrant proteins. Over 140 mutations in the human gene encoding the cytosolic homodimeric enzyme Cu/Zn-Superoxide Dismutase (SOD1) are linked to ALS. The key event in SOD1 associated ALS seems to be the pathological formation of toxic protein aggregates as a result of initially unfolded or partly structured SOD1-mutants. Here, we have compared the folding behaviour of a set of ALS associated SOD1 mutants. Based on our findings we propose that SOD1 mediated ALS can be triggered by a decrease in protein stability but also by mutations which reduce the net charge of the protein. Both findings are in good agreement with the hypothesis for protein aggregation. SOD1 has also been found to be able to interact with mitochondrial membranes and SOD1 inclusions have been detected in the inter-membrane space of mitochondria originating from the spinal cord. The obvious question then arose; does the misfolding and aggregation of SOD1 involve erroneous interactions with membranes? Here, we could show that there is an electrostatically driven interaction between the reduced apo SOD1 protein including ALS associated SOD1-mutants and charged lipid membrane surfaces. This association process changes the secondary structures of these mutants in a way quite different from the situation found in membrane free aqueous environment. However, the result show that mutants interact with charged lipid vesicles to lesser extent than wildtype SOD1. This opposes the correlation between decreased SOD1 stability and disease progression. We therefore suggest that the observed interaction is not a primary cause in the ALS mechanism.

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