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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.
121

Awareness of memory functioning and quality of life for people with dementia and their caregivers

Weavers, Thomas January 2016 (has links)
Background: Unawareness of memory functioning is a key symptom of Alzheimer’s disease and dementia that has been demonstrated to be related to a number of important factors for the person with dementia (PwD) and their family caregivers including quality of life and depression. Understanding more about how awareness relates to these factors will help inform how PwD and their caregivers are best supported. Objective: A meta-analysis was conducted in order to examine the relationship between Awareness and depression in dementia. An empirical study was conducted to examine the contribution awareness provides to explaining PWDs’ Quality of Life (QoL). PwD have been found to be aware of factors that affect their caregiver and so caregiver wellbeing and quality of life and the quality of the caregiving relationship were also investigated as well as more established predictors of quality of life for PwD. Both PwD self-ratings and caregiver ratings of the PwD they care for of QoL were examined as they have been shown to be affected by different factors. Method: Meta-analysis: A search of electronic databases Psycinfo, Embase and Medline was conducted. A meta-analysis of correlations was undertaken examining the relationship between awareness and depression in dementia. Empirical study: 27 PwD and their caregivers were recruited. In order to assess the research aims the PwD completed measures of: Quality of life (Quality Of Life-Alzheimer’s Disease scale), awareness of memory functioning (Memory Awareness Rating Scale-Adjusted), cognitive functioning (Addenbrooke’s Cognitive Exam-R), depression and anxiety (Hospital Anxiety and Depression Scale). The caregiver completed measures of: PwD Quality of life (Quality Of Life-Alzheimer’s Disease scale proxy), Memory Functioning Scale (from MARSA), self-ratings of depression and anxiety (Hospital Anxiety and Depression Scale), activities of daily living (Disability Assessment in Dementia), Neuropsychiatric symptoms (Neuropsychiatric symptoms inventory-Questionnaire), caregiver burden (Zarit Burden Inventory), and rating of relationship quality with PwD (Burns Relationship Satisfaction Scale). Results: Meta-analysis: Thirty-one studies were identified. A small association was found between awareness and depression with substantial amount of heterogeneity (- 0.23). Analysing the studies that excluded major depression demonstrated that mild depression had a moderate negative relationship with awareness (-0.42). Subgroup analysis showed that the different measures of awareness used seemed to suggest different effects with depression for different measures. Empirical study: Awareness was not found to predict PwD rated or caregiver rated QoL. No caregiver variables predicted PwD QoL. Depression and neuropsychiatric symptoms predicted PwD QoL. Caregiver rated QoL was predicted by activities of daily living and caregiver rated quality of caregiving relationship. Conclusions: Meta-analysis: The effect between mild depression and lack of awareness but not major depression supports the assertion that unawareness is a psychological response to decline in memory functioning in dementia. Neither depression nor awareness appear to be unitary constructs in PwD. Empirical study: Awareness not related to PwD QoL. The quality of caregiving relationship is important to QoL in a dementia context. PwD and their caregivers rate the QoL of PwD differently.
122

Närståendes upplevelser : I vårdandet av familjemedlemmar med Alzheimers sjukdom En litteraturöversikt / Relatives’ experiences : In caring for family members with Alzheimer's disease A literature review

El-Tai Abdel-Rehim, Aisha, Thörn, Erik January 2018 (has links)
Bakgrund: Enligt WHO drabbas ungefär tio miljoner människor av demens varje år varav 60 till 70 procent av Alzheimers sjukdom. I Sverige är upp emot var femte vuxen en regelbunden informell vårdgivare till någon i sin omgivning. Informell vård innebär den omsorg som närstående ger till vårdtagaren. Behovet av närståendes närhet ökar ofta under insjuknandet i Alzheimers sjukdom. Sjuksköterskan har en hälsofrämjande och sjukdomsförebyggande funktion och har en roll som rådgivare där denne vägleder vårdtagare och deras närstående. Syfte: Syftet var att belysa närståendes upplevelser kring vårdandet av familjemedlemmar med Alzheimers sjukdom. Metod: En litteraturöversikt genomfördes där tio artiklar med kvalitativ design granskades och analyserades enligt Friberg. Dessa artiklar framkom ur databaserna Cinahl Complete, Pubmed, Medline och PsykINFO. Sökord som användes var ”Alzheimers disease”, ”experience”, ”relatives” och ”family”. Resultat: Fyra huvudteman konstruerades. Transitionen från närstående till att bli vårdgivare, här framkom det att närstående upplevde maktlöshet, tvivel och en förlust av autonomi. Älta det förflutna och känna oro för framtiden, närstående upplevde en känsla av oro inför framtiden både för vårdtagaren och dem själva. Upplevelsen av stigmatisering och isolering, närstående upplevde att de blev isolerade och kände av en stigmatisering i samhället. Att förlora samhörigheten och stärka den, närstående belyste att relationen med vårdtagaren förändrades till följd av sjukdomens inverkan.  Diskussion: Resultatet diskuterades utifrån Callista Roys teori om adaption. Diskussionen fördes kring hur upplevelserna hos närstående kan förstås utifrån denna teori och det som framkom i resultatet. Närstående genomgår en övergång till att bli en vårdgivare och befinner sig i en föränderlig miljö där adaption eftersträvas för att finna en balans i livet. En diskussion fördes kring sjuksköterskans roll i samspelet med närstående. / Background: According to WHO, approximately ten million people are affected by dementia each year, of which 60 to 70 percent are suffering from Alzheimer's disease. In Sweden, every fifth adult is an informal caregiver to someone in their environment. Informal care involves the care that relatives give to their care recipient. At the onset of Alzheimer's disease, the need of closeness to the relatives often increases. The nurse has a health promoting and disease preventing function and has a role as an adviser in which he/she guides the care recipient and their relatives. Aim: The aim was to illustrate the experiences of relatives in caring for family members with Alzheimer´s Disease.  Method: A literature review was conducted where ten articles of qualitative design were examined and analyzed according to Friberg. These articles came from the databases Cinahl Complete, Pubmed, Medline and PsychInFO. Keywords used were "Alzheimers Disease", "Experience," "Relatives," and "Family." Results: Four main themes were constructed. The transition from relative to becoming a caregiver, here it emerged that relatives experienced powerlessness, doubt and a loss of autonomy. Dwelling on the past and Feeling worried about the future, relatives experienced a sense of concern for the future both for the care recipient and for themselves. The experience of stigmatization and isolation, relatives felt that they were isolated and felt stigma in society. The loss of togetherness and strengthen it, relatives explained that the relationship with the care recipient changed as a result of the effect of the disease.  Discussion: The results was discussed based on Callista Roys theory of adaptation. The discussion was conducted in relation to how the experiences of relatives can be understood based on this theory, and other findings that emerged from the results. Relatives undergo a transition to becoming a caregiver and are in a changing environment where adaptation is sought to find a balance in life. A discussion was held about the nurse's role in the interaction with relatives.
123

Química e atividades antioxidante e anticolinesterásica de espécies da família lycopodiaceae / Chemistry, antioxidant and anticholinesterasic activities of Huperzia and Lycopodium species

Konrath, Eduardo Luis January 2011 (has links)
A doença de Alzheimer é uma doença neurodegenerativa que causa perdas de memória, danos cognitivos e no comportamento, sendo considerada uma das causas principais de demência entre a população. Esta doença é caracterizada por uma intensa perda neuronal colinérgica, de forma que tanto os inibidores da enzima acetilcolinesterase (AChE) quanto compostos antioxidantes possam ser empregados como neuroprotetores. Nesse sentido, plantas da família Lycopodiaceae vêm sendo estudadas como fonte de novos alcalóides anticolinesterásicos desde a descoberta da huperzina A, isolada a partir da planta chinesa Huperzia serrata. Este trabalho foi realizado com o objetivo de caracterizar e isolar os alcalóides majoritários de Huperzia acerosa, H. heterocarpon, H. quadrifariata, H. reflexa, Lycopodiella cernua, Lycopodium clavatum e L. thyoides, de ocorrência no estado do Rio Grande do Sul, bem como avaliar as atividades anticolinesterásicas e antioxidantes in vitro e in vivo para os extratos. Extratos de alcalóides totais de espécies de L. clavatum e L. thyoides ocorrentes no Brasil e Argentina foram comparados quanto ao seu conteúdo químico, aliado à atividade anticolinesterásica. A atividade inibitória para AChE e butirilcolinesterase (BuChE) dos alcalóides isolados também foi ensaiada, juntamente com a determinação das propriedades citotóxicas exercidas pelos extratos sobre uma linhagem de gliomas C6. Todos os extratos de alcalóides foram analisados através de CG-EM, sendo os perfis de fragmentação dos compostos comparados através de dados da literatura. L. clavatum e L. thyoides possuem perfil químico similar, com licopodina e acetildiidrolicopodina como alcalóides principais, enquanto que L. cernua possui apenas dois alcalóides, cernuína e licocernuína. Os extratos de alcalóides de H. acerosa, H. quadrifariata e H. reflexa também foram analisados, sendo detectados tanto compostos do grupo licopodano quanto do grupo flabelidano, juntamente com outros alcalóides cujas estruturas ainda são desconhecidas. Os alcalóides encontrados em H. heterocarpon não puderam ser elucidados a partir de dados de fragmentação, uma vez que eles não coincidiram com nenhum perfil da literatura. Nesse estudo verificamos que dentre os extratos analisados, H. quadrifariata e H. reflexa promoveram a maior inibição para a enzima AChE obtida de eritrócitos humanos, com IC50 de 2,0 e 0,11 μg/mL, respectivamente, enquanto que H. heterocarpon foi o único extrato com maior seletividade para a BuChE (IC50 = 8,3 μg/mL). Além disso, dentre os alcalóides isolados licopodina, acetildiidrolicopodina, cernuína, licocernuína e clavolonina, apenas acetildiidrolicopodina e cernuína possuem inibição importante, sendo que nenhum deles possui efeito butirilcolinesterásico significativo. Também foi estimada a atividade anticolinesterásica para os extratos de alcalóides totais de L. clavatum e L. thyoides empregando-se homogenatos de córtex, hipocampo e estriato de ratos como fonte enzimática, sendo determinadas suas curvas de inibição com distintos tempos de incubação em uma faixa de concentrações. Também foi verificada para os dois extratos uma inibição do tipo competitiva/não-competitiva, bem como seu perfil antioxidante in vitro pelos métodos de descoloração do radical DPPH, degradação da 2-deoxirribose, TRAP e óxido nítrico. Após um tratamento agudo em camundongos de 14 meses com os extratos, foram verificados os efeitos antioxidantes através do método de TBA-RS, e para as enzimas catalase e superóxido dismutase. Do mesmo modo, verificamos que os mesmos extratos promoveram uma diminuição na atividade da acetilcolinesterase, quando administrados por via intraperitoneal. Nessa metodologia, os extratos mais potentes foram H. quadrifariata e H. reflexa, corroborando o efeito in vitro encontrado para os mesmos. Os extratos purificados de alcalóides de L. clavatum e L. thyoides com habitat no Brasil e Argentina foram comparados quanto ao seu perfil químico e biológico. Nesse estudo, foi verificado que os alcalóides licopodina e acetildiidrolicopodina são os compostos majoritários para todas as espécies, tendo L. clavatum maior atividade anticolinesterásica em relação a L. thyoides, tanto a espécie brasileira quanto a espécie argentina. / Alzheimer’s disease is a neurodegenerative disease which causes memory loss, cognitive and behavioral damages, considered to be the leading cause of dementia among the elderly. This disease is characterized for an intense cholinergic loss, and the use of acetylcholinesterase (AChE) inhibitors together with antioxidant compounds as neurprotectors is a strategy for the treatment. In this sense, Lycopodiaceae plants are well studied as a source of new anticholinesterasic alkaloids since the discovery of huperzine A, isolated from Chinese Huperzia serrata. This work was conducted with the objective of characterize and isolate the main alkaloids from Huperzia acerosa, H. heterocarpon, H. quadrifariata, H. reflexa, Lycopodiella cernua, Lycopodium clavatum and L. thyoides, with occurrence in Rio Grande do Sul state, and also evaluate the anticholinesterasic and antioxidant activities in vitro and in vivo for the extracts. Alkaloidal extracts from L. clavatum and L. thyoides species with habitat in Brazil and Argentina were compared to their chemical content, together with their anticholinesterasic activity. The inhibitory effect for AChE and butyrylcholinesterase (BuChE) for the isolated alkaloids was also evaluated, together with the determination of the cytotoxic properties exherced by the extracts in a gliome C6 cell line. Every alkaloidal extract was analyzed by means of GC-MS, and the fragmentation patterns for the compounds were compared with those from literature. L. clavatum and L. thyoides have similar chemical profile, with lycopodine and acetyldihydrolycopodine as main alkaloids, while L. cernua has only two alkaloids, cernuine and lycocernuine. The alkaloidal extracts of H. acerosa, H. quadrifariata e H. reflexa were also analyzed, and compounds from lycopodane and flabellidane groups were detected, along with other alkaloids whose structures are still unknown. The alkaloids found in H. heterocarpon could not be elucidated with fragmentation dates so far, since they did not coincide with those found in literature. We also verified that among the extracts, H. quadrifariata and H. reflexa promoted a higher inhibition for AChE obtained from human erythrocytes, with a IC50 value of 2,0 e 0,11 μg/mL, respectively, while H. heterocarpon extract was the only more selective for BuChE (IC50 = 8,3 μg/mL). Moreover, among the isolated alkaloid lycopodine, acetyldihydrolycopodine, cernuine, lycocernuine and clavolonine, only acetyldihydrolycopodine and cernuine possess an important inhibition, and none significantly inhibited butyrylcholinesterase. It was also assessed the anticholinesterase effect for the alkaloidal extracts of L. clavatum and L. thyoides employing cortex, hippocampus and striatum rat brain homogenates as enzymatic sources, being determined the incubation time-inhibition curves over a concentrations range. It was also verified for both extracts an inhibitory effect of the competitive/non competitive mixed type, as well as their in vitro antioxidant profile using the methods of DPPH radical decoloration, 2-deoxyrribose degradation, TRAP and nitric oxide. After an acute treatment in 14 months-aged mice, we verified the antioxidant effects though TBA-RS and also the enzymes catalase and superoxide dismutase. In the same way, we found out that the same extracts reduced the acetylcholinesterase activity when administered by intraperitoneal injection. Using this methodology, the most potent extracts were H. quadrifariata and H. reflexa, corroborating the in vitro effect found for them. The purified alkaloidal extracts of L. clavatum and L. thyoides with habitat in Brazil and Argentine were compared to their chemical and biological profile. In this study, we found out that lycopodine and acetyldihydrolycopodine are the main alkaloids found for all species, and L. clavatum possesses a better inhibition against AChE when compared to L. thyoides for both Brazilian and Argentinean collected species.
124

Estudo da natureza do prejuízo na fluência e nomeação de verbos na doença de Alzheimer e na afasia progressiva primária não-fluente

Beber, Bárbara Costa January 2014 (has links)
Introdução: Indíviduos com danos cerebrais podem apresentar dissociação na produção de verbos e substantivos. Há uma maior diversidade de transtornos neurológicos que apresentam prejuízo na produção de verbos do que de substantivos, e esses transtornos normalmente apresentam danos em circuitos cerebrais frontais. No entanto, pouco se sabe sobre a natureza do prejuízo na produção de verbos em cada transtorno neurológico. Objetivo: A presente tese de doutorado teve como objetivo investigar a produção de verbos em diferentes doenças neurodegenerativas e no envelhecimento normal através das tarefas de fluência e nomeação de verbos. Métodos: para atingir o objetivo geral, foram realizados três estudos que originaram três artigos científicos. O primeiro artigo realizou uma adaptação da tarefa de fluência de verbos para o português brasileiro, obteve a performance de 62 brasileiros idosos saudáveis para esta tarefa e a influência de fatores demográficos, clínicos e da aplicação de outras tarefas de fluência verbal previamente à fluência de verbos. O segundo artigo investigou a natureza dos déficits da produção de verbos na doença de Alzheimer (DA). Para isso 35 pacientes com DA em fase leve e moderada foram avaliados para as tarefas de fluência e nomeação de verbos, assim como 35 idosos saudáveis (controles). Também analisou-se a influência da frequência das palavras nas tarefas estudadas. O terceiro artigo, investigou a natureza dos déficits na produção de verbos na Afasia Progressiva Primária (APP) não-fluente. Foram avaliados 12 pacientes com APP não-fluente e 9 sujeitos controle. Todos partcipantes foram avaliados através de tarefas de nomeação e fluência de verbos e de substantivos. Um efeito de manipulabilidade foi estudado na tarefa de nomeação. Correlatos neurais foram investigados utilizado a técnica de Voxel Based Morphometry (VBM) a partir de imagens de ressonância magnética (RM) estrutural dos pacientes. Resultados: No primeiro artigo obteve-se a performance dos idosos saudáveis na fluência de verbos (11,73±5,80), a correlação com a escolaridade (r=0,616), MEEM escore total (r=0,399), MEEM Atenção e Cálculo (r=0,393), e MEEM Linguagem (r=0,322). Não houve influência da aplicação prévia de tarefas de fluência verbal na fuência de verbos. No segundo artigo, os pacientes com DA mostraram prejuízo tanto na tarefa de nomeação de verbos (p<0,000; F=36,983) quanto na fluência de verbos (p<0,000; F=21,460), porém a primeira foi mais comprometida que a segunda. A performance dos pacientes com DA na nomeação de verbos foi influenciada pela severidade da doença e pela frequência das palavras. No terceiro artigo, os pacientes com APP não-fluente foram comprometidos em todas tarefas de nomeação e de fluência verbal, porém foram significativamente piores em verbos do que em substantivos. Não houve efeito de manipulabilidade. As áreas atróficas Broadmann 44 (p<0,001) e giro pré-central (p<0,001) se correlacionaram com o prejuízo na nomeação de verbos, enquanto as áreas atróficas 44 e 45 de Broadman (p<0,001, ambas) se correlacionaram com o prejuízo na fluência de verbos. Conclusões: Nossos achados indicam que o prejuízo na produção de verbos parece ter uma natureza predominantemente semântica na DA e prodominantemente gramatical na APP não fluente. As evidências levantam questões importantes também para a neurobiologia da linguagem. / Background: Individuals with brain damage may show dissociation in the verb and noun production. There is a larger diversity of neurological disorders that show impairment in verbs rather in nouns, and these disorders use to present damage in the frontal brain circuits. However, little is known about the nature of the verb production impairment in each one of these neurological disorders. Objective: The current doctoral thesis had the aim of investigating the verb production in different neurodegenerative diseases and in the normal elderly, using verb fluency and verb naming tasks. Methods: to reach the main aim, we carried out three studies that resulted in three articles. In the first article we adapted the verb fluency task for Brazilian Portuguese, we obtained the performance of 62 healthy elderly people for this task, and we verified the influence of demographic and clinical factors as well as of the previous application of other verbal fluency tasks. The second article investigated the nature of the verb production deficits in the Alzheimer’s disease (AD). Thirty-five mild and moderate AD patients and 35 healthy controls were evaluated for verb fluency and verb naming tasks. It also analyzed the influence of word frequency in the used tasks. The third article investigated the nature of verb production deficits in the nonfluent variant of Primary Progressive Aphasia (nfPPA). Twelve patients with nfPPA and 9 healthy controls were evaluated for verb and noun fluency and naming tasks. A manipulability effect was studied in the naming task. Neural correlates were investigated by Voxel Based Morphometry (VBM) of structural Magnetic Ressonance Imaging (MRI) of the patients. Results: The first article obtained the healthy elderly people performance for verb fluency (11.73±5.80), a correlation with education (r=0.616), MMSE total score (r=0.399), MMSE Attention and Calculation (r=0.393), and with MMSE Language (r=0.322). There was no influence of previous application of verbal fluency tasks on the verb fluency. In the second article, the AD patients showed deficits in the verb naming (p<0.000; F=36.983) and in the verb fluency (p<0.000; F=21.460), however the first task was more impaired than the second one. The AD patients performance in the verb naming was influenced by the disease severity and by word frequency. In the third article, the nfPPA patients were impaired in all naming and fluency tasks, however they were significantly worse in verbs than in nouns. There was no effect of manipulability. Atrophy on BA 44 (p<0.001) and on precentral gyrus (p<0.001) correlated with impairment in verb naming. Atrophy on BA 44 and 45 (p<0.001 for both) correlated with impairment in verb fluency. Conclusions: Our findings indicate the verb production deficits seem to have a more predominant semantic nature in AD and more predominant grammatical nature in nfPPA. This evidence brings up important questions for the neurobiology of language.
125

Linking social, psychological and lifestyle factors to cognitive decline in aging: pathways and challenges to optimal function

Brown, Cassandra Lynn 02 January 2019 (has links)
The possibility that lifestyle factors may delay or accelerate cognitive decline in aging has garnered significant attention and a considerable body of research has formed. However, investigating the relations between social engagement and cognitive function in aging have been somewhat equivocal in their findings and there is a lack of understanding of the mechanisms by which social engagement may impact cognitive function and the role of factors limiting social engagement. The aim of this dissertation was to build on current understanding of how specific aspects of social relationships relate to cognitive functioning in older adulthood and how these aspects are affected by challenges and barriers to social participation. This dissertation is comprised of three studies addressing several specific research questions. Study one (Chapter 2) examined whether relations with cognitive performance over time differ for structural aspects of social relationships (social network and social contact) versus functional/subjective aspects of social relationships (loneliness and social support) and whether the associations are between cognitive performance and stable, “trait-like” components of social relationships or fluctuating “state-like” components of these constructs, using autoregressive latent trajectory modeling of data from the Health and Retirement Study. Study two (Chapter 3) used a multilevel modeling approach to examine whether the spouses/partners of individuals diagnosed with Alzheimer’s disease or dementia experience a within person decline in cognitive performance and whether changes in structural and functional/subjective aspects of social relationships interacted with a spouses’ diagnosis of memory disease to predict within person change in cognitive performance. Study three (Chapter 4) investigated whether rejection sensitivity, social avoidance, and fears of negative social evaluations were predictive of lack of social participation and loneliness in a sample of Vancouver Island older adults. These factors have previously been investigated in younger adults as risk factors for loneliness and social withdrawal, but social isolation in older adulthood is often attributed to lack of social opportunities. This dissertation demonstrates the importance of considering precise aspects of social relationships, including barriers to social participation, and their relations to cognitive functioning. / Graduate / 2019-12-12
126

Entropy-based nonlinear analysis for electrophysiological recordings of brain activity in Alzheimer's disease

Azami, Hamed January 2018 (has links)
Alzheimer’s disease (AD) is a neurodegenerative disorder in which the death of brain cells causes memory loss and cognitive decline. As AD progresses, changes in the electrophysiological brain activity take place. Such changes can be recorded by the electroencephalography (EEG) and magnetoencephalography (MEG) techniques. These are the only two neurophysiologic approaches able to directly measure the activity of the brain cortex. Since EEGs and MEGs are considered as the outputs of a nonlinear system (i.e., brain), there has been an interest in nonlinear methods for the analysis of EEGs and MEGs. One of the most powerful nonlinear metrics used to assess the dynamical characteristics of signals is that of entropy. The aim of this thesis is to develop entropy-based approaches for characterization of EEGs and MEGs paying close attention to AD. Recent developments in the field of entropy for the characterization of physiological signals have tried: 1) to improve the stability and reliability of entropy-based results for short and long signals; and 2) to extend the univariate entropy methods to their multivariate cases to be able to reveal the patterns across channels. To enhance the stability of entropy-based values for short univariate signals, refined composite multiscale fuzzy entropy (MFE - RCMFE) is developed. To decrease the running time and increase the stability of the existing multivariate MFE (mvMFE) while keeping its benefits, the refined composite mvMFE (RCmvMFE) with a new fuzzy membership function is developed here as well. In spite of the interesting results obtained by these improvements, fuzzy entropy (FuzEn), RCMFE, and RCmvMFE may still lead to unreliable results for short signals and are not fast enough for real-time applications. To address these shortcomings, dispersion entropy (DispEn) and frequency-based DispEn (FDispEn), which are based on our introduced dispersion patterns and the Shannon’s definition of entropy, are developed. The computational cost of DispEn and FDispEn is O(N) – where N is the signal length –, compared with the O(N2) for popular sample entropy (SampEn) and FuzEn. DispEn and FDispEn also overcome the problem of equal values for embedded vectors and discarding some information with regard to the signal amplitudes encountered in permutation entropy (PerEn). Moreover, unlike PerEn, DispEn and FDispEn are relatively insensitive to noise. As extensions of our developed DispEn, multiscale DispEn (MDE) and multivariate MDE (mvMDE) are introduced to quantify the complexity of univariate and multivariate signals, respectively. MDE and mvMDE have the following advantages over the existing univariate and multivariate multiscale methods: 1) they are noticeably faster; 2) MDE and mvMDE result in smaller coefficient of variations for synthetic and real signals showing more stable profiles; 3) they better distinguish various states of biomedical signals; 4) MDE and mvMDE do not result in undefined values for short time series; and 5) mvMDE, compared with multivariate multiscale SampEn (mvMSE) and mvMFE, needs to store a considerably smaller number of elements. In this Thesis, two restating-state electrophysiological datasets related to AD are analyzed: 1) 148-channel MEGs recorded from 62 subjects (36 AD patients vs. 26 age-matched controls); and 2) 16-channel EEGs recorded from 22 subjects (11 AD patients vs. 11 age-matched controls). The results obtained by MDE and mvMDE suggest that the controls’ signals are more and less complex at respectively short (scales between 1 to 4) and longer (scales between 5 to 12) scale factors than AD patients’ recordings for both the EEG and MEG datasets. The p-values based on Mann-Whitney U-test for AD patients vs. controls show that the MDE and mvMDE, compared with the existing complexity techniques, significantly discriminate the controls from subjects with AD at a larger number of scale factors for both the EEG and MEG datasets. Moreover, the smallest p-values are achieved by MDE (e.g., 0.0010 and 0.0181 for respectively MDE and MFE using EEG dataset) and mvMDE (e.g., 0.0086 and 0.2372 for respectively mvMDE and mvMFE using EEG dataset) for both the EEG and MEG datasets, illustrating the superiority of these developed entropy-based techniques over the state-of-the-art univariate and multivariate entropy approaches. Overall, the introduced FDispEn, DispEn, MDE, and mvMDE methods are expected to be useful for the analysis of physiological signals due to their ability to distinguish different types of time series with a low computation time.
127

Résurgence des traumatismes chez le sujet âgé, impact sur un processus démentiel et traitement : étude en institution auprès de sujets atteints de la maladie d'Alzheimer / Trauma resurgence in the elderly, impact on a dementia process and treatment : institutional study in patients with Alzheimer's disease

Delrue, Nicolas 01 December 2017 (has links)
Contexte – Cette recherche analyse les liens entre la pathologie démentielle de type maladie d’Alzheimer (MA) et le Trouble Stress Post Traumatique (TSPT) et vérifie si un traitement du TSPT chez les sujets souffrant de MA peut améliorer l’efficience de la mémoire épisodique, des fonctions cognitives globales et de la qualité de vie des patients. Méthode – Après avoir passé en revue la littérature sur les liens existants entre TSPT et pathologies de type MA, nous proposons l’hypothèse que la détection et le traitement d’un TSPT chez les sujets souffrant de MA pourrait améliorer la mémoire épisodique verbale et la mémoire autobiographique épisodique avec des effets positifs sur l’évolution de la pathologie démentielle. Nous présentons une recherche longitudinale, analysant les données recueillies auprès de 20 sujets cibles (TSPT et MA) et de 20 sujets témoins (MA sans TSPT). Durant trois sessions successives (T0, T1 et T2) séparées par des intervalles de six mois, les différentes composantes de la mémoire épisodique ont été suivies à l’aide de tests spécifiques. L’évolution d’une MA a été vérifiée avec le Mini-Mental State Examination (MMSE). Pour le groupe cible, la présence du TSPT et la qualité de vie ont été testées et un traitement du TSPT a eu lieu entre T0 et T1.Résultats – La littérature scientifique souligne des similitudes entre le TSPT et la MA, avec un rôle clé de la mémoire épisodique. Nos résultats confirment que le traitement d’un TSPT chez les sujets souffrant de MA améliore significativement tous les indicateurs testés : rappel et reconnaissance de mots, rappel immédiat et différé, rappel d’événements de vie, fonctionnement cognitif global et qualité de vie.Discussion/Conclusion – Des données solides existent en faveur de la proposition d’une détection systématique et d’un traitement du TSPT chez les patients avec MA. Cette recherche suggère une voie prometteuse pour les soins de patients atteints de MA et souffrant d’un traumatisme psychique non résolu. / Purpose – This research aims to analyze the links between Alzheimer’s disease (AD) and Post-Traumatic Stress Disorder (PTSD) and to verify if a PTSD treatment can improve episodic memory, global cognitive functioning and quality of life in AD patients.Methods – We review the literature about the links between PTSD and AD, building on several theoretical models. We propose the hypothesis that the treatment of PTSD in AD can improve verbal episodic memory and autobiographical episodic memory with some positive effects on AD evolution. We present a longitudinal study in order to confirm the likely benefits of such an approach. There were 20 participants in the target group (AD and PTSD) and 20 participants in the control group (AD without PTSD). During three sessions (T0, T1 and T2) separated by an interval of six months, different components of episodic memory were assessed with specific tests. AD evolution was assessed with the Mini-Mental State Examination (MMSE). For the target group, PTSD presence and quality of life were also assessed, and treatment for PTSD was undertaken between T0 and T1 for the target group.Results/Findings – The analysis of scientific literature highlighted some clinical, cognitive and neurobiological similarities between AD and PTSD with a key-role of episodic memory. The results of the research indicate that PTSD treatment in AD participants improves significatively all assessed indicators: word recall, word recognition, immediate recall, delayed recall, personal recent events recall, personal lifetime events recall, global cognitive abilities (MMSE) and quality of life.Discussion/Conclusion – There are strong theoretical and practical reasons to search for an effective intervention for PTSD in AD patients. This study indicate a promising avenue for therapeutic care of AD patients with involved trauma.
128

The role of N-truncated Aβ peptides in Alzheimer’s Disease

Lopez Noguerola, Jose Socrates 26 June 2018 (has links)
No description available.
129

Efeitos do treinamento com pesos nos sintomas depressivos e variáveis metabólicas em pacientes com doença de Alzheimer

Vital, Thays Martins [UNESP] 05 October 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-10-05Bitstream added on 2014-06-13T19:08:26Z : No. of bitstreams: 1 vital_tm_me_rcla.pdf: 1077397 bytes, checksum: 994b5ff7ab0a7455f5c40b9182e0bc3c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A doença de Alzheimer (DA) é caracterizada por alterações cognitivas, psicológicas, comportamentais, funcionais e metabólicas. Dentre estas alterações, destacamos os sintomas depressivos e as alterações metabólicas. A prática de atividade física tem se mostrado uma importante ferramenta não farmacológica que auxilia no tratamento da DA. Este estudo foi dividido em duas partes. O estudo 1 teve como objetivo caracterizar o nível de atividade física; analisar se há associação do nível de atividade física e sintomas depressivos e entre nível de atividade física e variáveis metabólicas em pacientes com DA. Participaram deste estudo 37 pacientes nos estágios leve e moderado da DA. Os sintomas depressivos foram avaliados pela Escala de Cornell para Depressão em Demência e pela Escala Geriátrica de Depressão; o nível de atividade física foi avaliado pelo Questionário Baecke Modificado para Idosos. Para mensurar as variáveis metabólicas (colesterol total, HDL, LDL, VLDL, triglicérides, glicemia e homocisteina sérica) os pacientes foram encaminhados a um laboratório especializado. Para traçar o perfil cognitivo global utilizamos o Mini-Exame do Estado Mental e o Montréal Cognitive Assessment. Para análise dos dados utilizamos o teste de Shapiro Wilk para verificar a distribuição dos dados. O teste de correlação de Spearman foi utilizado para verificar possíveis relações entre as variáveis analisadas. Os testes de t student e U Mann Whitney foram utilizados para comparar os grupos com maior e menor nível de atividade física. Admitiu-se nível de significância de 5% para todas as análises. O nível de atividade física encontrado foi considerado baixo. Pacientes mais ativos apresentam menos sintomas depressivos e menor... / Alzheimer's disease (AD) is characterized by cognitive, psychological, behavioral, functional and metabolic. Among these changes, we can detach the depressive symptoms and metabolic changes. The practice of physical activity has proved to be an important tool as a non-pharmacological treatment of these changes. This study was divided into two parts. The study 1 aimed to characterize the level of physical activity, analyze whether there is an association of physical activity level and depressive symptoms and between physical activity level and metabolic variables in patients with AD. The study included 37 patients in mild and moderate stages of DA. Depressive symptoms were assessed by the Cornell Scale for Depression in Dementia and the Geriatric Depression Scale, and the level of physical activity was assessed by the Baecke Questionnaire Modified for the Elderly. To measure the metabolic variables (total cholesterol, HDL, LDL, VLDL, triglycerides, blood glucose and serum homocysteine) patients were referred to a specialized laboratory. To characterize the overall cognitive profile, it was used the Mini-Mental State Examination and the Montréal Cognitive Assessment. For data analysis was used the Shapiro Wilk test to verify the data distribution. The Spearman correlation test was used to verify possible relations between the variables. The Student’s t test and U Mann Whitney test was used to compare the groups with higher and lower levels of physical activity. The level of significance was set at 5% for all analyses. The level of physical activity was found to be low. Patients that were more active showed less depressive symptoms and lower serum homocysteine concentration. Relationships were found between physical activity level and depressive symptoms according to the patient response; between physical activity level... (Complete abstract click electronic access below)
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Efeito do treinamento aeróbio nos níveis do fator de crescimento semelhante à insulina-1 e funções cognitivas na doença de Alzheimer / Effect of aerobic training in levels of insulin-like growth factor-1 and cognitive functions in Alzheimer's disease

Stein, Angelica Miki [UNESP] 18 December 2017 (has links)
Submitted by Angelica Miki Stein null (angelica_stein@yahoo.com.br) on 2018-02-15T15:11:26Z No. of bitstreams: 1 Tese completa - Stein AM_DR .pdf: 7740796 bytes, checksum: ed16030624fe5ab04287eb42146f66b8 (MD5) / Approved for entry into archive by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br) on 2018-02-15T18:42:06Z (GMT) No. of bitstreams: 1 stein_am_dr_rcla.pdf: 7526722 bytes, checksum: 99f7c1d945c7338609585fc2899edee0 (MD5) / Made available in DSpace on 2018-02-15T18:42:06Z (GMT). No. of bitstreams: 1 stein_am_dr_rcla.pdf: 7526722 bytes, checksum: 99f7c1d945c7338609585fc2899edee0 (MD5) Previous issue date: 2017-12-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Para auxiliar o tratamento da doença de Alzheimer (DA), existem alternativas não farmacológicas, como o exercício físico. Efeitos do exercício físico em supostos mecanismos como o fator de crescimento semelhante a insulina (IGF-1), tem sido associado a melhoras encefálica, relacionadas à melhora de desempenho cognitivo, neurogênese, depuração do peptídeo beta-amilóide e redução da tau fosforilada. Dessa forma, o objetivo geral desta tese foi verificar a relação entre exercício físico, níveis circulantes de IGF-1 e DA. A tese foi estruturada em 6 capítulos, sendo Capítulo 1: descrição dos objetivos, revisão de literatura e delineamento do estudo; Capítulo 2: artigo de revisão sistemática sobre os estudos que investigaram o efeito do exercício físico nas funções cognitivas e IGF-1 circulante em idosos; Capítulo 3: estudo que teve como objetivo comparar a resposta ao exercício aeróbio agudo nos níveis de IGF-1 circulante de idosos cognitivamente preservados e idosos com DA; Capítulo 4: o objetivo deste estudo foi verificar o efeito do treinamento aeróbio nas funções cognitivas e níveis de IGF-1 em idosos com DA; Capítulo 5: estudo que teve como objetivo comparar a resposta ao exercício aeróbio agudo na cognição e atividade encefálica em camundongos selvagens, pré sintomáticos da DA e com deficiência de IGF-1; Capítulo 6: considerações gerais e conclusões da tese. No Capítulo 2 foram encontrados 7 estudos que verificaram o efeito do exercício nos níveis de IGF-1 e na função cognitiva de idosos em diferentes condições, como idosos cognitivamente preservados, idosos com comprometimento cognitivo leve e idosos pré-diabéticos. Os resultados apontaram que não há consenso entre melhor tipo de exercício, intensidade, frequência e duração para provocar melhora das funções cognitivas e regulação de IGF-1 circulante. O capítulo 3 traz um estudo em que participaram 74 idosos: 40 idosos cognitivamente preservados e 34 idosos com doença de Alzheimer. Todos os participantes responderam a uma avaliação cognitiva e foram submetidos a um teste incremental em esteira ergométrica. Sobretudo, foi demonstrado que idosos com DA e idosos cognitivamente preservados responderam ao exercício aeróbio agudo de maneira diferente: idosos com DA tiveram aumento dos níveis de IGF-1 e idosos cognitivamente preservados tiveram manutenção nestes mesmos níveis. No Capítulo 4, 16 idosos com DA compuseram o Grupo Controle (GC) e 18 idosos com DA, o Grupo Treinamento (GT). O GT participou de um protocolo de treinamento aeróbio, realizado a 80% da frequência cardíaca, com duração de 25-40 min/sessão, três vezes semanais, com duração de 12 semanas. Após o período experimental, não foram identificadas diferenças significativas entre grupos e momentos para as funções cognitivas e níveis de IGF-1. Porém, resultados clínicos na cognição e no controle de quadros de insulino-resistência foram observados no GT. No Capítulo 5 foi verificado camundongos selvagens tiveram aumento significativo na banda theta e desempenho cognitivo superior quando comparados aos outros grupos de animais. Por último, o Capítulo 6 traz as considerações gerais e conclusões da tese: não existe um protocolo único capaz de modificar os níveis de IGF-1 e provocar melhora cognitiva; idosos cognitivamente preservados e idosos com DA respondem de maneira diferente ao exercício aeróbio agudo quanto aos níveis de IGF-1; o treinamento aeróbio adotado não foi efetivo para melhora cognitiva, nem para modificações nos níveis de IGF-1; camundongos selvagens, pré-sintomáticos da DA e com deficiência de IGF-1 respondem de maneira diferente ao exercício aeróbio agudo na atividade encefálica, sendo que o exercício agudo se mostrou efetivo no desempenho cognitivo. / To help the treatment of Alzheimer's disease (AD), there are non-pharmacological alternatives, such as physical exercise. Possible effects of physical exercise on putative mechanisms, such as the insulin-like growth factor-1 (IGF-1), have been associated with improvements on brain health, related to cognition, neurogenesis, clearance of the protein beta-amyloid and p-tau. Thus, the objective of this thesis was to verify the relation among physical exercise, circulating IGF-1 and AD. The thesis was structured in 6 chapters - Chapter 1: description of the objectives, literature review and design of the study; Chapter 2: systematic review manuscript about studies that investigated the physical exercise effects on cognitive functions and circulating IGF-1 in elderlies; Chapter 3: the objective was to compare the response to aerobic acute exercise in circulating IGF-1 levels in cognitively preserved elderly and elderly with AD; Chapter 4: the objective was to verify the aerobic training effect on cognitive functions and IGF-1 levels in elderly with AD; Chapter 5: the objective was to compare the response to acute aerobic exercise on cognition and brain activity in wild mice, pre symptomatic AD mice and IGF-1 deficiency mice; Chapter 6: general considerations and conclusions. In the Chapter 2, 7 papers verified the exercise effect on IGF-1 levels and cognitive function in elderlies with different conditions, as cognitively preserved elderly, mild cognitive impairment and pre diabetes was found. The results pointed that there was no consensus about recommendation of best type of exercise, intensity, frequency and duration to induce improvement on cognition and circulating IGF-1 regulation. The Chapter 3 brings a study with transversal profile, with 74 participants: 40 cognitively preserved elderly and 34 elderly with AD. All participants responded to cognitive evaluation and they were submitted to a incremental test in ergometric treadmill. Mainly, elderly with AD and cognitively preserved elderlies responded to acute aerobic exercise in different ways. Elderly with AD had an increase on IGF-1 levels whereas cognitively preserved elderlies had a maintaining in this same levels. In the Chapter 4 in order to verify the training effect on cognitive functions and IGF-1, 16 elderlies with AD participated in Control Group (CG) and 18 elderlies with AD, in Training Group (TG). The TG participated in an aerobic training protocol, 75% of heart rate, 4 km/h, 25-40 min/session, 3 times weekly, during 12 weeks. After the experimental period, significant differences between groups and moments for cognitive functions and IGF-1 levels were not identified. However, interesting clinical results was observed in cognition and insulin-resistance control of TG. In Chapter 5, wild mice had a significant increase on theta rhythm and better cognitive performance when they were compared to another animal groups. Finally, the Chapter 6 brings us general considerations and conclusions of the thesis: there is not only one protocol capable to modify IGF-1 levels and induce cognition improvement; cognitively preserved elderly and elderly with AD responded differently to acute aerobic exercise in IGF-1 levels; the training protocol adopted in this study was not effective neither to improve cognition, nor to modified IGF-1 levels in elderlies with AD; wild mice, AD pre symptomatic mice and IGF-1 deficiency mice responded different to acute aerobic exercise in brain activity, considering acute exercise effective on cognitive performance. / FAPESP: 2013/19729-0 / CAPES: PDSE 99999.010743/2014-06

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