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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.
111

Transcriptional Regulatory Networks in the Mouse Hippocampus.

MacPherson, Cameron Ross January 2007 (has links)
<p> <p>&nbsp / </p> </p> <p align="left">This study utilized large-scale gene expression data to define the regulatory networks of genes expressing in the hippocampus to which multiple disease pathologies may be associated. Specific aims were: ident i fy key regulatory transcription factors (TFs) responsible for observed gene expression patterns, reconstruct transcription regulatory networks, and prioritize likely TFs responsible for anatomically restricted gene expression. Most of the analysis was restricted to the CA3 sub-region of Ammon&rsquo / s horn within the hippocampus. We identified 155 core genes expressing throughout the CA3 sub-region and predicted corresponding TF binding site (TFBS) distributions. Our analysis shows plausible transcription regulatory networks for twelve clusters of co-expressed genes. We demonstrate the validity of the predictions by re-clustering genes based on TFBS distributions and found that genes tend to be correctly assigned to groups of previously identified co-expressing genes with sensitivity of 67.74% and positive predictive value of 100%. Taken together, this study represents one of the first to merge anatomical architecture, expression profiles and transcription regulatory potential on such a large scale in hippocampal sub-anatomy.</p>
112

Mass Spectrometry of Non-protein Amino Acids : BMAA and Neurodegenerative Diseases

Jiang, Liying January 2015 (has links)
Neurodegenerative diseases have been shown to correlate positively with an ageing population. The most common neurodegenerative diseases are amyotrophic lateral sclerosis (ALS), Parkinson’s disease and Alzheimer’s disease. The cause of these diseases is believed to be the interaction between genetic and environmental factors, synergistically acting with ageing. BMAA (β-methylamino-L-alanine) is one kind of toxin present in our environment and might play an important role in the development of those diseases. BMAA was initially isolated from cycad seeds in Guam, where the incidence of ALS/Parkinsonism-dementia complex among the indigenous people was 50 – 100 times higher than the rest of the world in the 1950’s. BMAA can induce toxic effects on rodents and primates. Furthermore, it can potentiate neuronal injury on cell cultures at concentrations as low as 10 µM. BMAA was reported to be produced by cyanobacteria, and could bio-magnify through the food chain. In this thesis, work was initially focused on the improvement of an existing analytical method for BMAA identification and quantification using liquid chromatography coupled with tandem mass spectrometry.  Subsequently, the refined method was applied to environmental samples for probing alternative BMAA producer(s) in nature and to seafood samples for estimation of human exposure to this toxin. In Paper I, a systematic screening of the isomers of BMAA in a database was performed and seven potential isomers were suggested. Three of them were detected or suspected in natural samples. In Paper II, a deuterated internal standard was synthesized and used for quantifying BMAA in cyanobacteria. In Paper III, Diatoms were discovered to be a BMAA producer in nature. In Paper IV, ten popular species of seafood sold in Swedish markets were screened for BMAA. Half of them were found to contain BMAA at a level of 0.01 – 0.90 µg/g wet weight. In Future perspectives, the remaining questions important in this field are raised.
113

Treatment of prion diseases with camelid antibodies

Jones, Daryl Rhys January 2013 (has links)
No description available.
114

Prevalencia, fenotipo clínico y neuropatológico del parkinsonismo asociado a mutaciones en el gen LRRK2

Gaig Ventura, Carles 25 March 2011 (has links)
Las mutaciones en el gen LRRK2, en especial la G2019S, parecen ser una causa relativamente frecuente de enfermedad de Parkinson (EP).Mutaciones en este gen se detectan en el 5-6% de los casos con EP familiar y en el 1-2 % de los casos esporádicos de diferentes poblaciones occidentales. La mutación R1441G del gen LRRK2 también es una causa frecuente de parkinsonismo en el País Vasco. Las hipótesis del presente trabajo son: 1) En Cataluña las mutaciones G2019S y R1441G del gen LRRK2 son causa de parkinsonismo tanto familiar como esporádico, 2) Las manifestaciones clínicas motoras y no motoras del parkinsonismo asociado a mutaciones en el gen LRRK2 son heterogéneas, y 3) El sustrato neuropatológico del parkinsonismo asociado a mutaciones en el gen LRRK2 es heterogéneo y determina el fenotipo clínico. En relación a estas hipótesis, los objetivos son: 1) Determinar la frecuencia de las mutaciones G2019S y R1441G del gen LRRK2 en pacientes con diagnóstico clínico de EP en un hospital terciario de Barcelona, 2) Definir el fenotipo clínico de los pacientes con EP portadores de una mutación en el gen LRRK2, y 3) Determinar la presencia de las mutaciones G2019S y R1441G del gen LRRK2 en cerebros diagnosticados de EP, de parkinsonimo degenerativo, o de degeneración lobar frontotemporal, y estudiar las características clínicas y patológicas de los casos portadores de una mutación en este gen. Los resultados y conclusiones son: 1) La frecuencia de mutaciones en el gen LRRK2 en pacientes con EP que atienden a una consulta especializada en un hospital terciario de Barcelona es del 5,3%, siendo la mutación G2019S la más frecuente (el 4,3% de los pacientes son portadores). La mutación R1441G es más infrecuente (0,7%). 2) Las mutaciones en el gen LRRK2 son más frecuentes en casos familiares de EP (un 9,6% de los casos son portadores) que en casos esporádicos (un 3,4% son portadores). Hasta en un 43,7% de los pacientes con mutaciones en el gen LRRK2 no existen antecedentes familiares de parkinsonismo. 3) Las características clínicas de los síntomas motores y no motores del parkinsonismo asociado a mutaciones en el gen LRRK2 es indistinguible de los observados en la EP clásica. 4) Las alteraciones neuropatológicas del parkinsonismo asociado a la mutación G2019S del gen LRRK2 son heterogéneas. Si bien el sustrato neuropatológico más frecuente es la patología tipo Lewy, describimos un caso que confirma que uno de los fenotipos neuropatológicos asociados a la mutación G2019S es la degeneración nigral inespecífica sin inclusiones distintivas. 5) No hemos detectado mutaciones en el gen LRRK2 en cerebros asociados a otro tipo de enfermedad neurodegenerativa diferente a la EP, como la demencia por cuerpos de Lewy, la parálisis supranuclear progresiva o la atrofia multisistémica. Su existencia habría que considerarla probablemente excepcional o coincidental. / LRRK2 G2019S mutation is a frequent cause of Parkinson’s disease (PD). This mutation is present in 5-6% of familial PD cases and 1-2 % of sporadic PD patients. LRRK2 R1441G is frequent in PD patients from the Basque country. We hypothesize that 1) In Catalonia, the G2019S and R1441G mutations are frequent in patients with familial as well as sporadic parkinsonism. 2) Clinical features in LRRK2-related parkinsonism are heterogeneous 3) The neuropathological substrate of LRRK2-related parkinsonism is pleomorphic and determines the clinical phenotype. We aim to assess 1) The frequency of the G2019S and R1441G mutations in patients with a clinical diagnosis of PD in Barcelona 2) The clinical phenotype of PD patients carrying a LRRK2 mutation, and 3) The presence of LRRK2 G2019S and R1441G mutations in brains diagnosed of PD, other neurodegenerative parkinsonism, as well as frontotemporal lobar degeneration, and assess the clinical and neuropathological features of those cases carrying a LRRK2 mutation. Results and conclusions: 1) LRRK2 mutations are frequent in PD patients from Barcelona (5.3% of them). The G2019S mutation is more frequent (4.3%) than the R1441G mutation (0.7%). 2) LRRK2 mutations are more frequent in familial PD cases (9.6% of them) than in sporadic cases (3.4%). Family history of parkinsonism is absent in up to 43.7% of patients with LRRK2 mutations. 3) Clinical features of motor and non-motor symptoms of LRRK2-related parkinsonism is indistinguishable from those of classical PD. 4) The neuropathological phenotype of LRRK2 G2019S-related parkinsonism is heterogeneous. Although the most frequent neuropathological substrate is Lewy boby type pathology, we describe a patient with non-specific nigral degeneration and the G2019S mutation. 5) We have not been able to identify LRRK2 mutations in brains of a neurodegenerative disease other than PD (e.g Lewy bodies dementia, Progressive supranuclear palsy or Multiple system atrophy). Presence of LRRK2 mutations in these neurodegenerative diseases would be exceptional or coincidental.
115

Genetic regulation of nerve injury-induced neurodegeneration and inflammation /

Swanberg, Maria, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
116

Excitotoxic neurodegeneration in mouse brain : roles of immune cells and cytokines /

Chen, Zhiguo, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
117

PTEN and Akt signalling in Alzheimer's disease /

Rickle, Annika, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.
118

Excitotoxicity in neurodegenerative disorders

Chen, Yongmei, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves : 176-210). Also available on the Internet.
119

The role of chronic traumatic encephalopathy on amyotrophic lateral sclerosis

Steen, Andrea Lee 08 April 2016 (has links)
It has been postulated that there could be a connection between traumatic brain injury (TBI) and motor neuron disease (MND), including amyotrophic lateral sclerosis (ALS). As chronic traumatic encephalopathy (CTE) is caused by repeated TBI and is a newly examined disease, there has been little evaluation of the potential relationship between CTE and ALS. It was proposed that CTE is a risk factor for not only MND, but also ALS. There is significant evidence that even a single TBI is a risk factor for Parkinson's disease (PD), thought to be invoked by the inflammatory process that the brain undergoes following a TBI. General rigorous physical activity with trauma to the trunk or extremities does not appear to be a risk factor for ALS. However, physical activity with associated head traumas, especially repeated head traumas, does seem to increase the likelihood of developing ALS. The biological mechanism for this is suspected to be increase in free radicals during exercise in individuals who are predisposed to decreased antioxidant function. Additionally, individuals who have suffered repeated head trauma, even amongst the general population in a non-athletic setting, has been shown to drastically increase the individual's chance of developing ALS. CTE, which is most common in athletes, is speculated to be caused by TAR DNA-binding protein 43 (TDP-43), tau neurofibrillary tangle (NFT), and beta-amyloid (A-Beta) protein inclusions in brain tissue following a multitude of TBI during high level sport activity. There are individuals who suffer initially CTE, followed by ALS, indicating CTE is clearly a risk factor for ALS. Anatomically, the TDP-43, NTF, and A-Beta; inclusions are present in the brain tissue of both individuals with CTE alone as well as the individuals with CTE and ALS. The anatomic difference between these two pathologies is the inclusion of these three proteins in the spinal cord of ALS patients as well. Unfortunately, there are indications that previous studies of professional athletes and their development of ALS have presented with significant issues including confounding factors of the subpopulation and sample sizing. Additionally, the anatomical cause of TBI leading to ALS is still unknown. Further evaluation on the relationship between head injury and ALS must be dedicated to investigating the mechanism involved in developed PD versus ALS following TBI. The biologic sequence following TBI that leads to ALS must be examined and compared to individuals whom develop ALS but did not suffer TBI. Moreover, an assessment must be made to determine what causes some individuals to develop protein inclusions solely in the brain tissue, leading to CTE, and some individuals to have an advancement of the protein inclusions into the spinal cord, leading additionally to CTE followed by ALS.
120

Polycyclic compounds as carriers for neuroactive non- steroidal anti-inflammatory drugs

Abaniwonda, Modupe January 2017 (has links)
Magister Pharmaceuticae - MPharm / Recent scientific findings have highlighted the beneficial roles of polycyclic cage compounds in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Further interest into the chemistry of these compounds is stimulated by their remarkable ability to improve the pharmacokinetics profile of known neuroprotective agents. As potent lipophilic scaffolds, they can be employed to target the brain delivery of desired compounds. Inflammation is a key mediator of neuronal cell's degeneration as activated microglia and other inflammatory mediators propagate oxidative damage and neuronal loss. Epidemiological and clinical evidence suggests that non-steroidal anti-inflammatory drugs (NSAIDs) slow down the progression and onset of neurodegenerative diseases. The beneficial effects of NSAIDs in ND can be attributed to their ability to inhibit cyclooxygenase enzymes thereby halting the biosynthesis of prostaglandins (PG) which are powerful mediators of inflammation. NSAIDs also inhibit the expression of pro- inflammatory genes. Despite their potential neuroprotective activity, NSAIDs are poorly lipophilic due to the presence of polar carboxylic acid groups and will therefore ionise at physiological pH, deterring them from reaching the desired site of action in the central nervous system (CNS).

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