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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.
71

Alzheimer: stress e qualidade de vida de cuidadores informais / Alzheimer: stress and life quality in informal caregivers

Horiguchi, Adriana Satomi 09 February 2010 (has links)
Made available in DSpace on 2016-04-04T18:27:51Z (GMT). No. of bitstreams: 1 Adriana Satomi Horiguchi.pdf: 1179274 bytes, checksum: 050e7a378439e733671628c42e01956e (MD5) Previous issue date: 2010-02-09 / Pontif?cia Universidade Cat?lica de Campinas / This study has the objective of analyzing and comparing the data of emotional stress, burden and life quality which were collected next to informal caregivers of patients with Alzheimer s disease and also comparing these data between Brazilian and Nippon-Brazilian cultures. The sample was composed by 20 caregivers, formed by 10 Brazilian caregivers and 10 Nippon-Brazilians. To collect the data it was used an Identification Form destined for the patient identification (answered by the caregiver), the Identification Form destined for the caregivers, the Stress Symptoms Inventory for Adults, the Life Quality Inventory and the Burden Interview. The general results point out that 75% of informal caregivers present stress, from whom 70% were in the resistance phase. It was detected a high level of failure in the life quality, in the health area, pointing out that this area is deeply affected. In the professional area it was also observed major failing scores. Comparing stress and burden, it was verified a significant difference between caregivers with and without emotional stress for privacy and burden feeling, having higher amounts of burden the participants with stress. Comparing the two groups there was a significant difference between the informal Brazilian caregivers and Nippon-Brazilians referring to the stress percentage. The Brazilian caregivers group obtained higher results of stress intensity in relation to the Nippon-Brazilian caregivers. / Este estudo tem por objetivo analisar e comparar os dados de stress emocional, sobrecarga e qualidade de vida, coletados junto a cuidadores informais de pacientes com a Doen?a de Alzheimer, e tamb?m, de comparar esses dados entre a cultura brasileira e nipo-brasileira A amostra foi composta por 20 cuidadoras, sendo 10 brasileiras e 10 nipo-brasileiras. Para a coleta de dados utilizou-se o Formul?rio de Identifica??o destinado ? identifica??o do paciente (respondido pela cuidadora), o Formul?rio de Identifica??o destinado ?s cuidadoras, o Invent?rio de Sintomas de Stress para Adultos, o Invent?rio de Qualidade de Vida e o Burden Interview. Os resultados gerais revelaram que 75% das cuidadoras informais apresentavam stress, das quais 70% encontravam-se na fase de resist?ncia. Foi constatado um alto n?vel de fracasso em qualidade de vida na ?rea da sa?de, revelando que esta se encontra profundamente afetada. Na ?rea profissional tamb?m foram observados maiores escores de fracasso. Comparando stress e sobrecarga, verificou-se diferen?a significativa entre as cuidadoras com e sem stress emocional para sa?de, privacidade e sentimento de sobrecarga, tendo maiores valores de sobrecarga as participantes com stress. Comparando-se os dois grupos, houve diferen?a significativa entre as cuidadoras informais brasileiras e nipo-brasileiras no que se refere ? porcentagem de stress. O grupo das cuidadoras brasileiras obteve maiores resultados de intensidade do stress em rela??o ao grupo de cuidadoras nipo-brasileiras.
72

Estudos estruturais e bioquímicos das septinas humanas bradeiona alfa e beta: moléculas relacionadas com o desenvolvimento de câncer do cólon, reto e melanoma maligno / Human SETPT4: heterologoes expression, Purification and biophysical characterization

Silva, Wânius José Garcia da 08 June 2005 (has links)
Septinas constituem uma família de proteínas de ligação a GTP que foram inicialmente identificadas em levedura Saccharomyces cerevisiae, mas também estão presentes em outros eucariotos com exceção de plantas. Septinas são purificadas de leveduras, Drosophila e cérebros de mamíferos na forma de filamentos, porém o mecanismo através do qual acorre a formação destes filamentos ainda não é muito bem compreendido. Septinas são constituídas de três regiões principais: um N-terminal variável, um domínio central GTPase altamente conservado e um domínio coiled-coil C-terminal. O gene SEPT4 foi identificado por M. Tanaka e colaboradores a partir do cDNA de cérebro humano e apresentou duas distintas transcrições: Bradeiona ? e ?. Interessantemente, além de cérebro e coração, as proteínas Bradeiona Α e Β. são detectadas somente em câncer do cólon, reto, próstata e melanoma maligno. Neste trabalho, o gene da proteína Bradeiona Β foi subclonado em um vetor de expressão bacteriano, produzido em E. coli e purificado com sucesso. O espectro de dicroísmo circular (CD) mostrou o perfil característico de proteínas com hélices a na estrutura secundária. Resultados de cromatografia de exclusão molecular (SEC) e espalhamento dinâmico de luz (DLS) indicam que a septina Bradeina foi produzida na forma de um estável oligômero com características monodispersivas, que foi subseqüentemente cristalizado em PEG6000. A atividade GTPase da Bradeiona Β foi comprovada através da técnica de eletroforese capilar (CE), mostrando-se absolutamente dependente de íons Mg2+. Inibição da atividade GTPase foi verificada em altas concentrações de Mg2+ (maiores que 5 mM). Com a finalidade de caracterizar os domínios preditos da Bradeiona Β (Fragmento Conservado e domínio GTPase), essas regiões foram previamente definidas, expressas em E. cozi e purificadas com sucesso. Resultados de CD, SEC, espectroscopia de fluorescência e NMR-600MHz indicam que o FC foi produzido na forma de um estável monômero com pouca estrutura secundária regular. Resultados de DLS e CD indicam que a fusão 6xHis-DGTPase foi produzida na forma de um oligômero com a presença de hélices a na estrutura secundária. A fusão 6xHis-DGTPase mostrou-se instável a altas concentrações na ausência de imidazol. A atividade GTPase da fusão GST+DGTPase foi comprovada, similarmente a Bradeiona , através da técnica de CE. Novamente, verificou-se dependência de íons Mg2+ (para a atividade catalítica) e inibição em altas concentrações de Mg2+. A fusão GST+DGTPase também foi capaz de hidrolisar ATP. Espera-se que as informações relatadas neste estudo proporcionem um alicerce para estudos estruturais/funcionais futuros das proteínas Bradeiona Α e Βoutras septinas. / Septins form a class of eukaryoyic guanine nucleotide-binding proteins that were first identified in budding yeast. Septins purified from yeast, Drosophila and mammalian brain form filaments, however the mechanism by which the filaments assemble is unclear. Septins have a highly conserved structure, which includes a central GTP-binding domain, a variable N-terminal region, and most septins also contain a coiled coil domain at the Cterminus. Bradeion p is one of the splice variants of the human septin gene, SEPT4, recently isolated by expression screening of an adult human brain cDNA library. The Bradeion gene resides at 17q23, and has been shown to present specific expression in both human colorectal cancer, urologic cancers and malignant melanoma. In order to characterize the GTPase activity of Bradeion Β , the protein was successfully expressed in E. coli and purified. The recombinant protein was characterized by circular dichroism (CD), dynamic light scattering (DLS) and a novel non-radioactive enzyme assay, which utilizes capillary electrophoresis (EC) to monitor GTP hydrolysis. The CD spectrum exhibited the typical shape characteristic of the presence of helical elements of secondary structure and the DLS pattern was indicative of a monodisperse solution, which was readily crystallized in the presence of PEG6000. GTP hydrolysis was shown to be Mg2+ dependent within the low millimolar range but at 5 mM was inhibitory. In order to characterize the predicted domains of Bradeion Β, these defined regions were successfully expressed in E. cozi and purified. The CD spectrum of CF exhibited the shape typically found for non-regular structure. The results of fluorescence spectroscopy, gel filtration (SEC) and NMR-600MHz also corroborate with the CD results indicating an irregular structure. The fusion protein 6xHis-DGTPase exhibited a CD spectrum with the typical shape characteristic of the presence of helical elements but was show to be instable at high concentrations in the absence of imidazole. To characterize the GTPase activity of the fusion protein GST+DGTPase, the CE technique was used to monitor GTP hydrolysis. Analysis by CE showed that GST+DGTPase was functional, since both GTP and ATP hydrolysis was observed in a Mg2+ dependent manner. This work provides novel approaches, which should aid in the fbture study of the structure and fùnction of Bradeion Α e Β, others septins and related GTPases.
73

Modulação atencional da percepção de tempo e suas relações com o envelhecimento e a doença de Alzheimer. / The effects of aging and Alzheimer\'s disease on the attencional modulation of time perception.

Campanha, Eduardo Vilodres 16 February 2009 (has links)
Os objetivos deste trabalho são avaliar o papel da atenção na percepção de tempo em jovens, idosos e pacientes com a doença de Alzheimer (DA). Nosso trabalho experimental consiste em 4 experimentos. Os experimentos 1 e 2 avaliaram a percepção de tempo em jovens, empregando tarefas de reprodução e de discriminação de durações temporais, respectivamente. Os resultados mostram um efeito atencional nas durações curtas com menor d. Os experimentos 3 e 4 compararam a percepção de tempo entre jovens, idosos e pacientes com DA, empregando tarefas de reprodução e de discriminação de tempo, respectivamente. Os resultados mostram um pior desempenho de idosos e pacientes com DA em relação aos jovens, que parece corresponder a uma deficiência atencional. Concluímos que a modulação da atenção apresenta papel fundamental e crítico na percepção de tempo e os déficits na percepção de tempo em idosos e em pacientes com DA parecem estar associada a uma menor quantidade de recursos atencionais ou a uma dificuldade de focar a atenção. / Our work focused on the attentional modulation of the perception of time. Additionally, other objective was to study the effect of aging and Alzheimers disease (DA) on temporal perception. We have performed four experiments. The first and the second experiments evaluated time perception in young volunteers, by means of the reproduction and discrimination of time intervals, respectively. The results showed an effect of attention on short durations, confirmed by d. The third and fourth experiments had the objective to compare time perception among young volunteers, elderly and DA patients, utilizing reproduction and discrimination of time intervals, respectively. Our findings showed a worse performance in both elderly volunteers and patients with DA in comparison with the group of young volunteers. Our conclusion is that time perception deficits in elderly and patients with DA are associated either to lesser attentional resources or to an increased difficulty in focusing attention on the target, which is more evident in patients suffering of DA.
74

Bone and Aluminium

Hellström, Hans-Olov January 2007 (has links)
<p>Osteoporosis is a major health care problem, by reason of its devastating consequences, in particular hip fractures. Worldwide it has been estimated that the incidence of hip fracture will increase to more than 6 million per year by 2050 compared to 1.7 million per year in 1990. Osteoporosis can be caused by various factors namely, genetic, lifestyle and environmental factors, and since the rising incidence of its consequences is not fully explained by the growing age of the population, there is an urgent need to identify individual causal factors of this condition. </p><p>The present research has focused on aluminium, one potential environmental factor of importance for bone disease, and its possible relation to osteoporosis, since it is known to cause osteoporosis-like bone disease and has been associated with induction of progressive central nervous system diseases.</p><p>Aluminium is the third most common element in the earth’s crust and the most abundant metal (8%). It is widely utilized industrially and it is also naturally present in many foods. Although aluminium is ubiquitous in the human environment, evolution has not given it an essential biological function.</p><p>The aluminium content of bone was measured by inductively coupled mass spectrometry in a large group of patients suffering from hip fractures, high energy fractures and osteoarthrosis. An exponential increase in aluminium content of bone with age was found (p=0.0004). However, no significant association of aluminium in bone with occurrence of hip fracture or dementia could be found, and no indirect evidence was obtained, e.g. through bone mineral density or biomechanical properties, that aluminium is involved in the pathogenesis of osteoporosis. Although we accumulate aluminium in bone throughout our lives, and there are experimental suggestions that aluminium induces premature cell death, the body content of this metal does not seem to influence the overall mortality risk. </p>
75

Etude des propriétés antiplasmodiales, antitrypanosomales et inhibitrices d'acetylcholinesterase de Triclisia sacleuxii (Pierre) Diels "Menispermaceae". / Study of antiplasmodial, antitrypanosomal and acetylcholinesterase inhibitory properties of Triclisia sacleuxii (Pierre) Diels "Menispermaceae"

Murebwayire, Sengabo 09 June 2008 (has links)
RESUME Le paludisme, la maladie la plus dévastatrice des régions tropicales fait l’objet de nombreuses recherches ayant pour but de trouver des médicaments préventifs, du matériel de protection, de nouveaux traitements, des vaccins, … Notre travail s’est inscrit dans la recherche des composés naturels actifs sur l’agent pathogène, le Plasmodium. Nos investigations phytochimiques et pharmacologiques ont porté sur Triclisia sacleuxii, une plante utilisée en médecine traditionnelle pour traiter diverses maladies dont deux parasitaires: la schistosomiase et l’ascardiose. Elle est aussi employée dans la préparation du poison de flèche. De plus, T. sacleuxii appartient à la famille des Menispermaceae, une famille riche en alcaloïdes bisbenzylisoquinoléiques (BBIQ). Ces composés ont de nombreuses propriétés biologiques dont l’activité antipaludique et trypanocide. Plusieurs autres espèces appartenant au genre Triclisia sont utilisées en médecine traditionnelle pour traiter la fièvre, le paludisme et d’autres pathologies. Ces éléments ont motivé la recherche dans cette plante des composés à activité antiplasmodiale. En effet, la plupart des composés que nous en avons isolés (p 12) sont actifs aussi bien sur la souche chloroquino-sensible (3D7) que sur la souche chloroquino-résistante (W2) que nous avons testées. Deux d’entre eux ont en plus une activité plus élevée vis-à-vis de la souche choroquino-résistante. Les composés actifs sur Plasmodium falciparum ont également montré une toxicité à l’égard de Trypanosoma brucei brucei, une sous-espèce apparentée à celles qui sont à la base de la maladie du sommeil en Afrique Centrale et de l’Est. A part les usages mentionnés précédemment, T. sacleuxii est en plus employée comme antidote contre les morsures de serpents. Ce qui voudrait dire qu’elle pourrait renfermer des inhibiteurs d’enzymes. Aussi, des BBIQ ont déjà démontré une activité inhibitrice de l’acétylcholinéstérase (AChE) et des phospholipases A2. Sur base de ces informations, nous avons assigné un troisième objectif à notre investigation qui cible l’AChE en correlation avec la maladie d’Alzheimer (MA). La MA est une pathologie neurodégénérative qui affecte en général les personnes âgées de plus de 60 ans, caractérisée entre autres par une perte progressive de la mémoire, une détérioration de plusieurs fonctions cognitives, de troubles neurologiques et du comportement, … Les différents extraits alcaloïdiques ont montré un degré d’inhibition de l’AChE élevé ( 80 - 90%) à une concentration de 100 μg/ml. Avec les composés purs, l’inhibition est très variable (30 - 90 %) suivant la structure. Enfin, nous avons effectué des investigations pour déterminer le mode d’action antiplasmodiale des BBIQ majeurs isolés de T. sacleuxii. Il apparaît que non seulement toutes les BBIQ n’agissent pas par un même mode d’action, mais aussi un même composé pourrait agir simultanément suivant deux ou plusieurs mécanismes différents. SUMMARY Malaria, the most devastating disease in tropical areas, is currently a target of numerous researches, aiming to find preventive medicines, protective tools, new treatments and vaccines. In a search for antiplasmodial natural compounds, we have undertaken phytochemical and pharmacological investigations on Triclisia sacleuxii, used in traditional medicine to treat various ailments including two parasitological diseases; schistosomiasis and ascariasis. It is also used as an arrow poison. Triclisia sacleuxii belongs to the Menispermaceae family, which is known to contain bisbenzylisoquinolines. These components have shown various biological activities among which antimalarial and trypanocidal activity. Furthermore, many Triclisia species are used in traditional medicine for treating fever and malaria along with other disorders. With this background the research was set out to investigate on possible antiparasitic compounds active against Plasmodium falciparum. Most of the compounds isolated in this work were active towards both chloroquine sensitive strain (3D7) and chloroquine resistant Plasmodium strain (W2). Interestingly some of them demonstrated selectivity for the resistant strain. The compounds which displayed antiplasmodial activity also showed toxicity against Trypanosoma brucei brucei, a parasite related to those which cause sleeping sickness. Besides Triclisia sacleuxii traditional uses mentioned above, it is also used as a snakebites antidote. This suggests that it might contain enzymes inhibitors. Additionally, in previous works, bisbenzylisoquinolines which are believed to be present in T. sacleuxii, have displayed phospholipases A2 and acetylcholinesterase inhibitory activity. On the basis of these informations, the third aim of our investigation targeted acetylcholinesterase (AChE), an enzyme involved in Alzheimer’s disease (AD). AD is a neurodegenerative disease occurring mostly in people aged beyond 60 years, characterised by a progressive loss of memory, impairement of multiple cognitive functions, neurological and behavior disorders,.... Our results have demonstrated that leaves, stems and roots alkaloidal fractions have high anti-AChE activity. Pure compounds exhibited a structure-dependent activity ranging from 30 up to 90% at a concentration of 100μg/ml). Finally, we have undertaken an investigation on the antiplasmodial mode of action of the major alkaloids. It appears that not only the BBIQ do not act by a same mechanism, but also a single compound may act by more than one mode of action.
76

Human brain function evaluated with rCBF-SPECT : memory and pain related changes and new diagnostic possibilities in Alzheimer’s disease

Sundström, Torbjörn January 2006 (has links)
The aim of this doctoral thesis was to study the influence of memory, pain, age and education on the regional cerebral blood flow (rCBF), i.e. brain function, in early Alzheimer's disease (AD) and in chronic neck pain patients in comparison to healthy controls and in healthy elderly per se. This was done by optimizing single photon emission computed tomography (SPECT) as a method to study rCBF with the tracer Technetium-99m (99mTc) hexamethylpropyleneamine oxime (HMPAO) and by matching all image data to a brain atlas before evaluation. The rCBF-SPECT was evaluated and developed to obtain higher diagnostic accuracy in AD and in chronic neck pain patients it was used to study basic pain related cerebral processes in chronic pain of different origin. A new semimanual registration method, based on fiducial marker, suitable for investigations with low spatial resolution was developed. The method was used to reconstruct images with an improved attenuation and scatter correction by using an attenuation-map calculated from the patients' previously acquired CT images. The influence of age and education on rCBF was evaluated with statistical parametric mapping, SPM in healthy elderly. The main findings were age related changes in rCBF in regions close to interlobar and interhemispheric space but not in regions typically affected in early AD, except for the medial temporal lobe. The theory of a 'cognitive reserve' in individuals with a longer education was supported with findings in the lateral temporal lobe, a region related to semantic memory, and in the frontal lobe. A cross-sectional study of chronic neck pain patients showed extensive rCBF changes in coping related regions in a non-traumatic pain patients compared to both healthy and a pain group with a traumatic origin, i.e. whiplash syndrome. The whiplash group displayed no significant differences in rCBF in comparison with the healthy controls. This suggests different pain mechanisms in these groups. The AD-patients showed a significantly lower rCBF in temporoparietal regions including left hippocampus. These changes were associated to episodic memory performance, and especially to face recognition. The diagnostic sensitivity for AD was high. The face recognition test (episodic memory) was used in AD patients to improve the sensitivity of method, i.e. memory-provoked rCBF-SPECT (MP-SPECT). The results were compared to healthy controls and the reductions of rCBF in temporoparietal regions were more pronounced in mild AD during provocation. Memory provocation increased the sensitivity of AD-related rCBF changes at group level. If a higher sensitivity for AD at the individual level is verified in future studies, a single MP-SPECT study might then be of help to set diagnosis earlier. In conclusion rCBF in temporoparietal regions are associated to an impaired episodic memory in early AD. Changes in these regions do not have a strong connection to chronological age. The diagnostic sensitivity of rCBF-SPECT in AD is high and there is a potentially higher sensitivity if memory provoked investigations are used. The findings in this thesis have given an increased knowledge of underlying cerebral pain processing in non-traumatic and traumatic (whiplash) neck pain. Preliminary results supporting the theory of 'cognitive reserve' by showing a correlation between long education and preserved rCBF was found in healthy elderly.
77

Bone and Aluminium

Hellström, Hans-Olov January 2007 (has links)
Osteoporosis is a major health care problem, by reason of its devastating consequences, in particular hip fractures. Worldwide it has been estimated that the incidence of hip fracture will increase to more than 6 million per year by 2050 compared to 1.7 million per year in 1990. Osteoporosis can be caused by various factors namely, genetic, lifestyle and environmental factors, and since the rising incidence of its consequences is not fully explained by the growing age of the population, there is an urgent need to identify individual causal factors of this condition. The present research has focused on aluminium, one potential environmental factor of importance for bone disease, and its possible relation to osteoporosis, since it is known to cause osteoporosis-like bone disease and has been associated with induction of progressive central nervous system diseases. Aluminium is the third most common element in the earth’s crust and the most abundant metal (8%). It is widely utilized industrially and it is also naturally present in many foods. Although aluminium is ubiquitous in the human environment, evolution has not given it an essential biological function. The aluminium content of bone was measured by inductively coupled mass spectrometry in a large group of patients suffering from hip fractures, high energy fractures and osteoarthrosis. An exponential increase in aluminium content of bone with age was found (p=0.0004). However, no significant association of aluminium in bone with occurrence of hip fracture or dementia could be found, and no indirect evidence was obtained, e.g. through bone mineral density or biomechanical properties, that aluminium is involved in the pathogenesis of osteoporosis. Although we accumulate aluminium in bone throughout our lives, and there are experimental suggestions that aluminium induces premature cell death, the body content of this metal does not seem to influence the overall mortality risk.
78

Contribution of FDG-PET and MRI to improve Understanding, Detection and Differentiation of Dementia

Dukart, Jürgen 22 March 2011 (has links) (PDF)
Progression and pattern of changes in different biomarkers of Alzheimer’s disease (AD) and frontotemporal lobar degeneration (FTLD) like [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) and magnetic resonance imaging (MRI) have been carefully investigated over the past decades. However, there have been substantially less studies investigating the potential of combining these imaging modalities to make use of multimodal information to further improve understanding, detection and differentiation of various dementia syndromes. Further the role of preprocessing has been rarely addressed in previous research although different preprocessing algorithms have been shown to substantially affect diagnostic accuracy of dementia. In the present work common preprocessing procedures used to scale FDG-PET data were compared to each other. Further, FDG-PET and MRI information were jointly analyzed using univariate and multivariate techniques. The results suggest a highly differential effect of different scaling procedures of FDG-PET data onto detection and differentiation of various dementia syndromes. Additionally, it has been shown that combining multimodal information does further improve automatic detection and differentiation of AD and FTLD.
79

Pathological Alterations Induced by intraneuronal in Alzheimer’s Disease

Christensen, Ditte Zerlang 28 October 2009 (has links)
No description available.
80

Deciphering the Catalytic Mechanism of the Zn Enzyme Glutaminyl Cyclase and the Deduction of Transition-State Analog Inhibitors

Piontek, Alexander 25 April 2014 (has links)
No description available.

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