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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.
151

MAPT mutation associated with frontotemporal dementia and parkinsonism (FTDP-17)

Haussmann, Robert, Wysocki, Marek, Brandt, Moritz D., Hermann, Andreas, Donix, Markus 03 June 2020 (has links)
We present a 56-year-old patient suffering from frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17). The history included a three-generation pedigree and the patient was found to be a mutation carrier. The diagnosis was hindered by late appearance of the hypokinetic movement disorder. For clinicians, it is important to consider rare neurodegenerative disease variants in early-onset familial dementia syndromes with behavioral, cognitive, and motor symptoms
152

Analýza fonace u pacientů s Parkinsonovou nemocí / Analysis of phonation in patients with Parkinson's disease

Kopřiva, Tomáš January 2015 (has links)
This work deals with analysis of phonation in patients with Parkinson’s disease (PD). Approximately 90% of patients with Parkinson’s disease suffer from speech motor dysfunction called hypokinetic dysarthria. System for Parkinson’s disease analysis from speech signals is proposed and several types of features are examined. Czech Parkinson’s speech database called PARCZ is used for classification. This dataset consists of 84 PD patients and 49 healthy controls. Results are evaluated in two ways. Firstly, features are individually analysed by Spearman correlation, mutual information and Mann-Whitney U test. Classification is based on random forests along with leave-one-out validation. Secondly, SFFS algorithm is employed for feature selection in order to get the best classification result. Proposed system is tested for each gender individually and both genders together as well. Best result for both genders together is expressed by accuracy 89,47 %, sensitivity 91,67% and specificity 85,71 %. Results of this work showed that the most important vowel realizations for phonation analysis are sustained vowels pronounced with maximum or minimum intensity (not whispering).
153

The effect of selected medicinal plants on rotenone-induced toxicity in SH-SY5Y neuroblastoma cells

Seoposengwe, K.M. (Keabetswe Millicent) January 2013 (has links)
Parkinson's disease (PD) is the second most common chronic neurodegenerative disease characterized by dopamine decrease in the substantia nigra. Currently, there is no promising cure for PD and this has resulted in extensive research into alternative medicines. The aim of this study was to investigate the effect of methanol and ethyl acetate extracts of Lannea schweinfurthii (Engl. Engl) (Anacardiaceae), Zanthoxylum capense (Thunb. Harv) (Rutaceae), Scadoxus puniceus ((L.) Friis & Nordal) (Amaryllidaceae) and Crinum bulbispermum (Burm. f.) Milne-Redh. & Schweick) (Amaryllidaceae) on rotenone-induced toxicity in SH-SY5Y neuroblastoma cells. The latter which mimics PD symptoms in vitro. Cytotoxicity of the plant extracts was assessed using sulforhodamine B (SRB) assay. Intracellular reactive oxygen species (ROS) were measured fluorometrically with the use of the fluorescent dye 2‟,7‟-dichlorodihydrofluorescein diacetate (H2DCF-DA). Intracellular glutathione content was measured fluorometrically after staining with monochlorobimane (MCB). Fluorescent dye 5,5‟ ,6,6‟ -tetrachloro-1,1‟ ,3,3‟ -tetraethylbenzimidazolcarbocyanine iodide (JC-1) was used to assess the mitochondrial membrane potential (MMP) status of cells. Apoptosis was assessed by determining caspase-3 activity through detection of 7-amino-4-methylcoumarin (AMC) which is a product of caspace-3 substrate, acetyl-Asp-Glu-Val-Asp 7-amino-4-methylcoumarin (Ac-DEVD-AMC), cleaved by the caspase-3 enzyme. Rotenone was used as an in vitro model to induce PD-like symptoms. Cytotoxicity studies for methanol extract of Zanthoxylum capense revealed the highest IC50 value of 121.3 μg/mL, indicating low toxicity. The ethyl acetate extract of Crinum bulbispermum was observed to have no effect on the normal proliferation of the SH-SY5Y cells and produced an IC50 value >100 μg/mL. The calculated IC50 value obtained from rotenone cytotoxicity studies was 112 iv nM. Zanthoxylum capense and Scadoxus puniceus plant extracts were observed to be neuroprotective against rotenone-induced toxicity. A decrease in intracellular glutathione content as well as MMP was also observed in cells exposed to rotenone alone (50 nM). There was no intracellular ROS generation observed in cells exposed to rotenone alone (50 nM) after 24 h and 72 h. However, apoptotic cell death was observed in cells treated with rotenone (50 nM). Intracellular ROS production was observed to be elevated by methanol and ethyl acetate extracts of C. bulbispermum. Methanol extracts of Z. capense was observed to increase intracellular glutathione content. MMP was increased effectively following treatment with ethyl acetate extract of C. bulbispermum. Moreover, both methanol and ethyl acetate plant extracts were found to decrease caspase-3 activity significantly (p<0.05), in cells exposed to 50 nM rotenone. Z. capense methanol extract reduced caspase-3 activity the most effectively. Treatment with plant extracts was protective and decreased cell death. Furthermore, L. schweinfurthii, Z. capense, S. puniceus and C. bulbispermum, demonstrated strong antioxidant and anti-apoptotic effects against rotenone-toxicity, making them potential agents in developing therapies for treating PD. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Pharmacology / unrestricted
154

Assessment of brainstem function with auricular branch of vagus nerve stimulation in Parkinson’s disease

Weise, David, Adamidis, Melanie, Pizzolato, Fabio, Rumpf, Jost-Julian, Fricke, Christopher, Classen, Joseph January 2015 (has links)
Background: The efferent dorsal motor nucleus of the vagal nuclei complex may degenerate early in the course of Parkinson’s disease (PD), while efferent nucleus ambiguous, the principal source of parasympathetic vagal neurons innervating the heart, and afferent somatosensory nuclei remain intact.
155

Idiopathic Phantosmia: Outcome and Clinical Significance

Landis, Basile N., Reden, Jens, Hähner, Antje January 2010 (has links)
Background/Aim: Little is known about the clinical significance of phantosmia. The literature on phantosmia indicates that this symptom has a wide range of differential diagnoses. However, most cases of phantosmia remain of unknown origin. Our goal was to follow up patients with idiopathic phantosmia, with special regard to improvement rates and possible severe health conditions preceded by phantosmia of unknown origin. Methods: Forty-four patients with idiopathic phantosmia which had consulted our Ear-Nose-Throat Smell and Taste Clinic over the last 10 years were contacted by telephone and underwent a structured medical interview. Results: None of the patients had eveloped any severe health condition or Parkinson’s disease. More than 5 years after the occurrence of hantosmia, more than 50% of the patients experienced disappearance (31.8%) or improvement (25%). In the remaining cases, phantosmia did not change (38.7%) or became worse ( ! 5%). Conclusion: The main findings of the present study were that idiopathic phantosmia improves or disappears in almost two thirds of the patients after more than 5 years, and that idiopathic phantosmia seems to be more likely a harmless symptom rather than a reliable predictor of early Parkinson’s disease or other severe diseases. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
156

Nicotine, Neural Plasticity, and Nicotine’s Therapeutic Potential

Brown, Russell W., Gill, W. Drew 01 January 2019 (has links)
This review is a brief summary of the effects of nicotine on neural plasticity and behavior, with a focus on the preclinical literature and the effects of nicotine on neurotrophic factors. Focus areas include underlying mechanisms of nicotine addiction and the therapeutic potential for nicotine and nicotinic receptor agonists in Parkinson’s disease, Alzheimer’s disease, traumatic brain injury, as well as cutting across these different areas of research with a brief review of the antiinflammatory effects of nicotine. It is clear that agonists at nicotinic receptors have therapeutic potential, but this should be weighed in the context of the effects of nicotine across the brain and its enhancement of neurotrophic factors. Although nicotine may have neuroprotective properties, it is important to keep in mind that these same effects underlie its addictive characteristics.
157

Effects of Parkinson’s disease on motor asymmetry

Watson, Deborah Mazanek 08 August 2023 (has links) (PDF)
Introduction: Persons with Parkinson’s disease (PD) experience changes cortically, subcortically and behaviorally. This dissertation examines the asymmetry of motor behavior to explore the role of asymmetry in persons with PD and its connection to clinical symptoms. Purpose: Project 1: To assess the hand asymmetry difference in young adults versus older adults. Project 2: To investigate the difference in hand asymmetry in older adults and persons with PD. Project 3: To explore the correlation between function and clinical symptoms of persons with PD. Methods: 55 right-handed participants [Young Adults (YA) = 20, Female = 10; Older Adults (OA) = 20, Female = 10; Persons with PD = 15, Female = 5] were recruited and performed motor tasks: Purdue Pegboard test, grip strength test, response task, thumb opposition task, tapping task, three variations of timed-up-and-go test (TUG), single leg stance task (SLS), Weight Distribution test and Limits of Stability test. The two-way ANOVA was conducted to examine a variance between YA and OA. A separate two-way ANOVA was conducted comparing variance between OA and persons with PD. The purpose was to explore asymmetries, characterized by a significant difference between groups’ left and right sides. Pearson’s correlation was implemented to examine connection of clinical symptoms and motor behavior. Statistics: IBM SPSS 24 software was used. Two 2-way ANOVAs with the between group factor of group (Young vs. Older in Project 1; Older vs. PD in project 2), and within group factor of hand (Right vs. Left in Study 1 & Study 2) were used to examine if age (or PD) changes hand asymmetry. Pearson’s correlation coefficient was used to determine correlations between Unified Parkinson’s Disease Rating Scale (UPDRS) and motor tasks in PD patients (Study 3). Results: Project 1: Results indicate asymmetry reduces with age in fine motor tasks containing speed, dexterity and strength components. Project 2: The basal ganglia dysfunction does not overall further exacerbate the reduced asymmetry with age. Project 3: Clinical symptoms of PD measured by the UPDRS are generally not associated with fine motor tasks of this study.
158

Differenzierung neurodegenerativer Parkinsonsyndrome mittels vestibulär evozierter myogener Potentiale und Gleichgewichtsprüfung

Klunk, Dietrich 08 June 2023 (has links)
Objective: Vestibular Evoked Myogenic Potentials (VEMP) were investigated to differentiate between parkinsonian syndromes. We correlated balance and VEMP parameters to investigate the VEMP brainstem circuits as possible origin for postural instability. Methods: We assessed clinical status, ocular and cervical VEMP (oVEMP, cVEMP) and a balance assessment (posturography, Activities-specific Balance Confidence Scale, Berg Balance Scale, modified Barthel Index) in 76 subjects: 30 with Parkinson’s disease (PD), 16 with atypical parkinsonism (AP) and 30 healthy controls. VEMP were elicited by using a mini-shaker on the forehead. Results: Patients with PD had a prolonged oVEMP n10 in comparison to controls and prolonged p15 compared to controls and AP. Patients with AP showed reduced oVEMP amplitudes compared to PD and controls. CVEMP did not differ between groups. Postural impairment was higher in AP compared to controls and PD, particularly in the rating scales. No correlations between VEMP and posturography were found. A classifier using support vector machine was able to automatically classify controls and patient subgroups with moderate to good accuracy based on oVEMP latencies and balance questionnaires. Conclusions: Both oVEMP and posturography, but not cVEMP, may be differentially affected in PD and AP. We did not find evidence that impairment of the cVEMP or oVEMP pathways is directly related to postural impairment. Significance: OVEMP and balance assessment could be implemented in the differential diagnostic work-up of parkinsonian syndromes.:1. Einleitung 2. Publikationsmanuskript 3. Zusammenfassung 4. Literaturverzeichnis 5. Anlagen 6. Darstellung des eigenen Beitrages 7. Selbstständigkeitserklärung 8. Lebenslauf 9. Danksagung
159

Motor Sequence Learning Deficits in Idiopathic Parkinson’s Disease Are Associated With Increased Substantia Nigra Activity

Tzvi, Elinor, Bey, Richard, Nitschke, Matthias, Brüggemann, Norbert, Classen, Joseph, Münte, Thomas F., Krämer, Ulrike M., Rumpf, Jost-Julian 27 March 2023 (has links)
Previous studies have shown that persons with Parkinson’s disease (pwPD) share specific deficits in learning new sequential movements, but the neural substrates of this impairment remain unclear. In addition, the degree to which striatal dopaminergic denervation in PD affects the cortico-striato-thalamo-cerebellar motor learning network remains unknown. We aimed to answer these questions using fMRI in 16 pwPD and 16 healthy age-matched control subjects while they performed an implicit motor sequence learning task. While learning was absent in both pwPD and controls assessed with reaction time differences between sequential and random trials, larger error-rates during the latter suggest that at least some of the complex sequence was encoded. Moreover, we found that while healthy controls could improve general task performance indexed by decreased reaction times across both sequence and random blocks, pwPD could not, suggesting disease-specific deficits in learning of stimulus-response associations. Using fMRI, we found that this effect in pwPD was correlated with decreased activity in the hippocampus over time. Importantly, activity in the substantia nigra (SN) and adjacent bilateral midbrain was specifically increased during sequence learning in pwPD compared to healthy controls, and significantly correlated with sequence-specific learning deficits. As increased SN activity was also associated (on trend) with higher doses of dopaminergic medication as well as disease duration, the results suggest that learning deficits in PD are associated with disease progression, indexing an increased drive to recruit dopaminergic neurons in the SN, however, unsuccessfully. Finally, there were no differences between pwPD and controls in task modulation of the cortico-striato-thalamo-cerebellar network. However, a restricted nigral-striatal model showed that negative modulation of SN to putamen connection was larger in pwPD compared to controls during random trials, while no differences between the groups were found during sequence learning. We speculate that learning-specific SN recruitment leads to a relative increase in SN- > putamen connectivity, which returns to a pathological reduced state when no learning takes place
160

Alpha-Synuclein Pathology Coincides With Increased Number of Early Stage Neural Progenitors in the Adult Hippocampus

Bender, Hannah, Fietz, Simone A., Richter, Franziska, Stanojlovic, Milos 03 April 2023 (has links)
Alpha-synuclein pathology driven impairment in adult neurogenesis was proposed as a potential cause of, or at least contributor to, memory impairment observed in both patients and animal models of Parkinson’s disease (PD) and Dementia with Lewy Bodies (DLB). Mice overexpressing wild-type alpha-synuclein under the Thy-1 promoter (Thy1-aSyn, line 61) uniquely replicate early cognitive deficits together with multiple other characteristic motor and non-motor symptoms, alpha-synuclein pathology and dopamine loss. Here we report overt intracellular accumulation of phosphorylated alphasynuclein in the hippocampus of these transgenic mice. To test whether this alters adult neurogenesis and total number of mature neurons, we employed immunohistochemistry and an unbiased stereology approach to quantify the distinct neural progenitor cells and neurons in the hippocampal granule cell layer and subgranular zone of 6 (prodromal stage) and 16-month (dopamine loss) old Thy1-aSyn mice. Surprisingly, we observed an increase in the number of early stage, i.e., Pax6 expressing, progenitors whereas the numbers of late stage, i.e., Tbr2 expressing, progenitors and neurons were not altered. Astroglia marker was increased in the hippocampus of transgenic mice, but this was not specific to the regions where adult neurogenesis takes place, arguing against a commitment of additional early stage progenitors to the astroglia lineage. Together, this uncovers a novel aspect of alpha-synuclein pathology in adult neurogenesis. Studying its mechanisms in Thy1-aSyn mice could lead to discovery of effective therapeutic interventions for cognitive dysfunction in PD and DLB.

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