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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.
521

O processo de degeneração dos partidos políticos no Brasil / Degeneration process of political parties in Brazil.

Pedro Rubez Jehá 23 June 2009 (has links)
Este trabalho é dedicado à análise do fenômeno partidário brasileiro. Mais especificamente, apresenta maiores detalhes de algumas de suas feições degeneradas e busca identificar, no ordenamento jurídico brasileiro, as possíveis principais causas normativas que expliquem este processo para, em seguida, propor alternativas possivelmente capazes de combatê-lo. O foco do estudo é essencialmente jurídico, visto que, os partidos políticos, após longa e deliberada omissão dos legisladores (constitucionais, principalmente), desde meados do século XX, vêm afirmando sua presença nos ordenamentos jurídicos de todo o mundo. Hoje, portanto, os partidos políticos são amplamente reconhecidos como um dos principais players do cenário político e, como tal, têm merecido uma atenção cada vez maior dos juristas. Pois se o direito em geral e o constitucional em particular - interessa-se por todos os principais aspectos que envolvem o processo de aquisição, exercício e perda do poder político dentro do Estado, nada mais natural que também passe a interessar-se em regular o funcionamento destas associações especificamente constituídas para este propósito. Entretanto, apesar de reconhecido e regulado pelo direito legislado, o fenômeno partidário está sujeito à incidência de uma série de dinâmicas próprias que só podem ser investigadas sob o prisma sociológico ou político. Esta é uma realidade que não pode ser ignorada pelo jurista que se aventurar em apontar a necessidade de realização de ajustes normativos nas regras do jogo político. Por este motivo, o trabalho, apesar de seu enfoque jurídico, busca na ciência política evidências empíricas que apontem para a adequação ou inadequação das normas vigentes e das propostas ao final formuladas. O primeiro capítulo focalizará, principalmente, a evolução histórica dos partidos políticos brasileiros. O segundo enumerará algumas das principais características degeneradas de nosso sistema partidário. Finalmente, o terceiro procurará apontar as causas normativas para as deficiências encontradas e proporá, quando necessários, ajustes na regulamentação partidária, eleitoral e institucional vigentes. / This work is dedicated to the analysis of the Brazilian partisan phenomenon. More specifically, it presents greater details of some of its depraved features and tries to identify, in the Brazilian legal system, the main possible normative causes that explain this process for, after that, to consider altematives possibly capable to fight it. The focus of the study is essentially legal, since, the political parties, afier long and deliberated omission of the legislators (constitutional, mainly), since middle of century XX, come affirming its presence in the legal systems of the whole world. Today, therefore, the political parties are widely recognized as one of the main players of the politician scene and, as such, have deserved more and more attention from the jurists. Therefore, if the law in general - and specially the constitutional law - are interested for all the main aspects that involve the process of acquisition, exercise and loss of the politician power within the State, nothing more natural than also interest itself in regulating the functioning of these associations specifically constituted for this intention. However, although recognized and regulated for the legislated law, the partisan phenomenon is put under the incidence of a special dynamic series that only can be investigated under the sociological or politician prisms. This is a reality that cannot be ignored by the jurist who ventures himself in pointing the necessity of accomplishment of normative adjustments in the rules of the politician game. For this reason, the work, although its legal approach, searches in science politics empirical evidences that indicates the adequacy or inadequacy of the effective norms and of the proposals formulated at the end. The first chapter will focus, mainly, the historical evolution of the Brazilian political parties. The second will enumerate some of the main depraved characteristics of our partisan system. Finally, the third will try to point the normative causes related to the joined deficiencies and will consider, when necessary, adjustments in partisan, electoral and institutional effective rules.
522

Efeitos da somatotropina recombinante bovina sobre as características espermáticas, concentrações de testosterona e IGF1 no plasma seminal de touros (Bos taurus taurus) submetidos à degeneração testicular / Recombinant bovine somatotropin effects on testosterone and IGF1 levels of bulls (Bos taurus taurus) under testicular degeneration

Luiz Waldemar de Oliveira Souza 01 September 2004 (has links)
Dentre os diversos fatores que provocam diminuição no desempenho reprodutivo, a degeneração testicular térmica é o motivo mais freqüente de baixa fertilidade em Bos taurus no Brasil. Baseados nos efeitos sobre a secreção de hormônios hipofisários e gonadais, o GH vem sendo estudado para o tratamento da infertilidade masculina. Um delineamento experimental tipo blocos ao acaso utilizou dezesseis touros adultos submetidos a 4 tratamentos em esquema fatorial 2x2 (0 e 96 horas de insulação testicular, 0 e 1,2 mg bST/kg PV), com o objetivo de testar os efeitos da bST no tratamento de touros submetidos a insulação testicular. Motilidade, alterações de acrossoma, defeitos de cauda e cabeça, gota protoplasmática proximal e defeitos espermáticos totais aumentaram em conseqüência da insulação testicular. As concentrações seminais de Testosterona foram temporariamente diminuídas em resposta a insulação testicular. A ocorrência de gota protoplasmática distal, anomalias de peça intermediária e concentrações seminais de IGF1 não foram afetadas pela insulação testicular. A somatotropina recombinante bovina não afetou as características espermáticas ou concentrações seminais de Testosterona e IGF1. / Testicular heat degeneration is the most common cause of poor fertility of Bos taurus bulls in the tropics. The Growth Hormone has been studied in man infertility treatment with some progress. A randomly blocks experimental design used 16 mature bulls allotted in 4 treatments in a 2x2 factorial arrangement (0 e 96 hours of scrotal insulation, 0 e 1,2 mg bST/kg BW) was performed to asses the effects ob bulls submitted to scrotal insulation. Motility, abnormal acrosome, tail and head defects, proximal droplet, and abnormal sperm increased, and seminal plasma Testosterone was temporally increased in response to scrotal insulation. Distal droplet, midpiece and seminal plasma IGF1 were not affected by bST. The bST did not affect sperm characteristics or seminal Testosterone and IGF1.
523

Estudo da regeneração simpática pós simpaticotomia seletiva experimental (ramocotomia) / Study of sympathetic regeneration post experimental selective sympathicotomy (ramicotomy)

Humberto Alves de Oliveira 06 March 2009 (has links)
Introdução: A simpatectomia torácica é o único tratamento, definitivo e eficaz, para a hiperidrose primária. A ramicotomia é um procedimento cirúrgico tão eficaz, mais conservador e com menos efeitos adversos que a simpatectomia convencional, contudo foi abandonada pela alta taxa de recidiva, atribuída, até então, à secção incompleta dos ramos comunicantes, ao desenvolvimento de outras vias de condução para o estímulo central e à regeneração neural. A avaliação histológica dos ramos comunicantes simpáticos após a ramicotomia, pode ajudar a entender o processo de recidiva dos sintomas da hiperidrose e, dessa forma contribuir para o desenvolvimento de estratégias para evitá-la. MATERIAL E MÉTODOS: 28 suínos foram submetidos à ramicotomia por videotoracospia e divididos randomicamente em 5 grupos, sacrificados com 15, 45, 90, 135 e 180 dias de pós-operatório (DPO). Os segmentos operados foram removidos cirurgicamente e submetidos à avaliação macroscópica da regeneração assim como análise histológica dos ramos comunicantes brancos e cinzentos para quantificação da reação inflamatória, deposição de fibras de colágeno grossas e finas, fibras reticulares e células de Schwann por imuno-histoquímica. Os dados foram comparados ao grupo controle, composto por segmentos intactos, não operados. RESULTADOS: Não houve regeneração macroscópica no grupo de 15 DPO sendo presente em 41,6% dos casos no grupo 180 DPO (p < 0,05). A reação inflamatória foi determinante no processo de degeneração Walleriana, com presença importante das células de Schwann nos ramos pré-ganglionares (p < 0,05), as células de Schwann apresentaram evolução semelhante nos dois ramos a partir do grupo de 45DPO, mantendo-se em menor número nos ramos cinzentos. As fibras de colágeno foram cruciais na cicatrização e as fibras reticulares importantes na regeneração neural, com correlação negativa entre elas (r = - 0,414; p < 0,01). A deposição de fibras de colágeno foi maior nos ramos cinzentos, apresentando pico de deposição no grupo 135 DPO e declínio importante no grupo 180 DPO (p < 0,05). CONCLUSÕES: A ramicotomia permite a secção completa de todos os ramos comunicantes do gânglio simpático. A taxa de regeneração histológica deve ser maior que a taxa de recidiva dos sintomas no humano, devido a regenerações não funcionais. O processo regenerativo é similar nos ramos brancos e cinzentos, com tendências menores para os últimos. A regeneração dos ramos comunicantes deve ser um dos principais fatores de recidiva da hiperidrose após a ramicotomia / INTRODUCTION: Thoracic sympathectomy is the only definitive and efficient treatment for primary hyperhidrosis. The ramicotomy is a surgical procedure that is as efficient as conventional sympathectomy but more conservative, having less adverse effects then conventional sympathectomy. This procedure was abandoned on account of the high recurrence rate, attributed to the incomplete section of the rami communicantes and to the development of new pathways of conduction to the central stimuli. MATHERIAL AND METHODS: Twenty-eight swine underwent bilateral videothoracoscopic ramicotomy and were randomly divided into 5 groups. The animals were sacrificed at 15, 45, 90, 135 and 180 days post-operative POD. The segments were removed and evaluated for macroscopic regeneration and histological analysis of the white and gray rami communicantes analyzing the inflammatory reaction, deposition of thin and thick collagen fibers, reticular fibers and Schwann cells. The data was compared to intact segments of sympathetic trunk as a positive control. RESULTS: There was neither macroscopic nor microscopic regeneration at the 15 POD group. The remaining groups had an average of 41,6% of regeneration, more significant at the 180 POD group (p<0.05). The inflammatory reaction was crucial in the process of Wallerian degeneration, with an important participation of the Schwann cells in the pre-ganglionic rami (p<0.05). The Schwann cells presented a similar evolution in both rami beginning at the 45 POD group, with a smaller count in the gray rami. The collagen fibers were significant in the cicatrization and the reticular fibers were important in neural regeneration, with a meaningful negative correlation between them (r = - 0,414; p < 0,01). The rate of deposition of the collagen fibers was greater in the white rami when compared to the gray rami in the first trimester and less important in the second trimester (p<0.05). CONCLUSIONS: Ramicotomy allows complete section of all rami communicantes of the sympathetic ganglia. The histological regeneration might be greater than the recurrence rates of clinical symptoms as seen in the human being due to non-functional regenerations. The restoration process is similar in both white and gray rami, with smaller tendencies in the last one. The regeneration of the could be one of the main factors for recurrence of hyperhidrosis following ramicotomy
524

Cuprúria em pais de pacientes com doença de Wilson antes e depois da administração oral de d-penicilamina / Cupriuresis in parents of patients with Wilson disease before and after oral intake of d-penicillamine

Jakeliny Vieira 31 May 2007 (has links)
A doença de Wilson (DW) é distúrbio da excreção biliar de cobre, de herança autossômica recessiva, devido a mutações no gene ATP7B. O cobre que não se liga à apoceruloplasmina circula no organismo ligado a aminoácidos, deposita-se principalmente no fígado e no cérebro e é excretado pelos rins. A cuprúria maior que 100ug/24h pode auxiliar no diagnóstico, embora cerca 20% dos pacientes com DW apresentem níveis anormais de cuprúria basal. A administração da d-penicilamina (DPA) pode promover, em crianças, valores maiores que 1.600ug/24h. A fim de se conhecer os níveis de cuprúria de possíveis indivíduos heterozigotos adultos, foram avaliados 25 pais e 25 mães de pacientes (média 61 anos em homens; 57 anos em mulheres) com diagnóstico de DW. Foram obtidos os níveis séricos de enzimas hepáticas, cobre e ceruloplasmina, e quantificada a cuprúria de 24h. A seguir, os indivíduos receberam DPA 1,0g por via oral dividido em duas tomadas, durante nova coleta de urina para dosagem de cuprúria de 24h. Esta análise foi realizada pelo método de espectrometria de absorção atômica eletrotérmica. Os níveis de enzimas hepáticas foram semelhantes nos dois grupos, exceto o nível médio de fosfatase alcalina que foi maior nas mulheres (H= 68,72 UI/L; M=81,68 UI/L). Os níveis de ceruloplasmina (H=21,72mg/dL; M=27,78mg/dL) e de cobre sérico (H=71,38 ?g/dl; M=88,0 ug/dl) foram maiores em mulheres do que em homens (p<0,001). Os níveis de cuprúria basal foram 22,43ug/24h (média) e 21,40ug/24h (mediana); e, após a DPA, de 523,54 ug/24h (média) e 511,5 ug/24h (mediana). A cuprúria média basal masculina foi de 26,19. ug/24h, enquanto a feminina foi de 18,28. ug/24h (p=0,005). Com o presente estudo, ficou definida possível faixa de variação da cuprúria antes e depois da administração de dpenicilamina em pais de portadores com doença de Wilson; que os pais apresentaram cupremia e níveis de ceruloplasmina menores e cuprúria basal maior do que as mães; que as faixas de variação de normalidade para os parâmetros ceruloplasmina, cobre sérico e urinário deveriam ser diferenciadas de acordo com o sexo. / Wilson disease is a biliary copper excretion disturbance, of recessive autossomic heritage, due to ATP7B gene mutations. The copper not bound to apoceruloplasmin circulates in the organism bound to amino acids and accumulates mainly in the liver and brain being excreted by the kidneys. Urinary copper higher than 100ug/24h can be useful in the diagnosis, but only about 20% of Wilson disease patients have abnormal basal levels. In this case, d-penicillamine (DPA) administration can lead, in children, to levels higher than 1.600ug/24h. Twenty five fathers and twenty five mothers of wilson disease patients (mean 61 years for male, and 57 years for female) were assessed in order to obtain urinary copper levels of probable heterozygote adults. Fasting liver enzymes, copper and ceruloplasmin serum levels were obtained along with 24h urinary copper excretion. After, patients got DPA 1.0g by oral route, twice a day, while collecting urine for 24h urinary copper excretion dosage. These analyses were performed by elethrotermic atomic absortion spectrometry method. Liver enzyme levels were similar in men and women but those of alkaline phosphatase were higher in women (M= 68.72 UI/L; F=81.68 UI/L). Serum ceruloplasmin (F=21.72mg/dl; F=27.78mg/dl) and copper (M=71.38 ug/dl; F=88.0 ug/dl) levels were higher in women than in men (p<0.001). Urinary copper levels before DPA were, 43ug/24h (mean) and 21.40 ug/24h (median); and, after DPA, 523.54 ug/24h (mean) and 511.5 ug/24h (median). Basal urinary copper levels in men were 26.9 ug/24h, and in women were 18.67 ug/24h (p=0.005). With the results of this study, we defined a possible range for urinary copper before and after oral intake of DPA in parents of Wilson disease patients. Furthermore, fathers had lower levels of serum copper and of ceruloplasmin, and greater levels of baseline cupriuresis than mothers; and finally the normal range for serum copper and ceruloplasmin, and urinary copper should be differentiated according to the gender.
525

Qualidade de vida visual em pacientes com degeneração macular relacionada à idade neovascular tratados com antiangiogênicos / Vision-related quality of life in neovascular age-related macular degeneration patients treated with antiangiogenics

Reinaldo Flávio da Costa Ramalho 07 August 2018 (has links)
INTRODUÇÃO: A degeneração macular relacionada à idade (DMRI) é a principal causa de perda de visão irreversível e cegueira mundialmente. A perda da visão central interfere nas atividades de vida diária, como o reconhecimento facial, leitura e escrita, direção de veículos automotores e em atividades funcionais e de lazer. Esta perda de visão relaciona-se também com o desencadeamento de quadros de ansiedade e depressão. Este estudo avaliou a qualidade de vida visual em pacientes com degeneração macular relacionada à idade neovascular por meio do questionário de função visual 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25). MÉTODOS: Estudo clínico observacional de 87 pacientes de ambos os sexos, com idade >= 50 anos e com o diagnóstico de DMRI neovascular unilateral ou bilateral. Todos os pacientes responderam ao questionário de função visual NEI VFQ- 25 no final do tratamento em regime Tratar e Estender ou PrONTO, com as drogas antiangiogênicas ranibizumabe ou aflibercepte. RESULTADOS: A idade dos pacientes foi a variável que menos influenciou a qualidade de vida visual dos pacientes. O gênero teve uma influência um pouco maior que a idade, no entanto, a lateralidade da doença demonstrou maior influência na qualidade de vida visual, comparada ao gênero e idade dos pacientes e foi significante para oito dos 12 domínios do questionário de função visual NEI VFQ-25. Os pacientes com acometimento bilateral tiveram pontuações mais baixas que os com doença unilateral em todos os domínios do questionário. A acuidade visual corrigida (AVc) foi a variável que apresentou o maior número de domínios com valores significantes e, portanto, foi a variável que mais se correlacionou com a qualidade de vida visual. A AVc do melhor olho (MO) foi significante para a maioria dos domínios relacionados com a visão, ao contrário do pior olho (PO) que não foi significante para nenhum domínio do questionário. CONCLUSÃO: Todas as variáveis testadas afetaram a qualidade de vida visual dos pacientes, onde a lateralidade teve uma maior influência, seguida pela idade e sexo dos pacientes. Na tomada de decisão para o tratamento de pacientes com DMRI neovascular, pelo menos para esta população, a manutenção da AVc do MO >= 0,5 (escala decimal de Snellen) foi essencial para a manutenção de boa qualidade de vida visual, independente da AVc do PO, que não teve efeito significante em nenhum domínio do questionário de função visual NEI VFQ-25 / INTRODUCTION: The neovascular age-related macular degeneration (AMD) is the main cause of irreversible loss of vision and blindness woldwide. The loss of the central visual field interferes on daily activities such as facial recognition, reading and writing, driving as well as functional and leasure activities. This loss of vision may also increases anxiety and depression for this age group. To evaluate the impact of neovascular AMD on the visual quality of life of patients using the 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25). METHODS: This was an observational clinical, with 87 patients of both genders, with age >= 50 years and a clinical diagnosis of unilateral or bilateral neovascular age related macular degeneration. All patients answered the visual functioning questionaire NEI VFQ-25 at the end of the treatment with the Treat and Extend or PrONTO regimen using antiangiogenic drugs ranibizumab or aflibercept. RESULTS: The age of patients was the variable with the lower influence on the quality of life of the patients. Gender had an influence slightly higher then the age, however, the laterality of the disease had the highest influence on the quality of life, compared with age and gender, and was significant for 8 of the 12 domains of the visual functioning questionaire NEI VFQ-25. The patients with bilateral age-related macular degeneration had lower scores than patients with unilateral disease for all domains of the questionaire. Visual acuity was the variable with the higher number of domains with significant values, and therefore the variable with the higher correlation with the quality of life. The visual acuity of the best eye (BE) was significant for most of the vision related domains, in opposition the the visual acuity of the worst eye (WE) which was not significant for any domain of the questionaire. CONCLUSION: All variables tested affected the visual quality of life, where the laterality of the disease had the highest influence, followed by the age and gender of the patients. The decision process for the treatment of patients with neovascular AMD, at least for this population, keeping the visual acuity of the BE >= 0,5 (Snellen\'s decimal scale) was essential to maintain a long term quality of life, despite the visual acuity of the worst eye, that had no significant effect on any domain of the visual functioning quaestionaire NEI VFQ-25
526

Elaboração e estabilidade de bebida láctea acidificada, carbonatada, aromatizada e enriquecida com luteína

Bastos, Gabriel Gomes 26 August 2016 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-08-28T13:10:36Z No. of bitstreams: 0 / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-30T14:36:00Z (GMT) No. of bitstreams: 0 / Made available in DSpace on 2017-08-30T14:36:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-08-26 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / O soro de leite, proveniente da fabricação de queijos diversos, ainda é um grave problema na indústria de laticínios, tendo em vista que seu descarte tem um impacto negativo no meio ambiente e seu tratamento por vezes se torna economicamente inviável. Diante do exposto, o presente trabalho visa produzir uma bebida láctea acidificada, aromatizada, carbonatada e enriquecida com luteína. A fim de aproveitar este produto disponível na indústria láctea, altamente rico em proteínas, vitaminas e minerais, para a fabricação de uma bebida refrescante, adicionada de dióxido de carbono (CO2), e considerada de possível uso funcional, uma vez que foi adicionado o extrato de luteína. O soro para a fabricação da bebida foi obtido a partir da fabricação do queijo Minas Frescal. O produto foi produzido em 4 repetições e cada repetição foi analisada ao longo do período máximo de 120 dias, sendo aplicados dois tratamentos: sob refrigeração e em temperatura ambiente. O produto apresentou estabilidade microbiológica durante todo o tempo de estocagem (120 dias) nas diferentes temperaturas, não apresentando contagem de microrganismos, confirmando a eficácia das barreiras microbiológicas aplicadas (pH, CO2 e tratamento térmico). As análises sensoriais demonstraram que o produto apresentou boa aceitação e que o mais aceito foi aquele armazenado sob refrigeração, bem como a aceitação se mostrou inversamente proporcional ao tempo de estocagem, sendo que a viscosidade aumentou ligeiramente em função do tempo de estocagem, para o produto conservado sob refrigeração. O extrato de luteína foi adicionado ao produto aumentando sua atividade antioxidante, o que pode auxiliar no fortalecimento do tecido formador da mácula ocular, prevenindo sua degeneração e aumentando a sua resistência contra doenças relacionadas. O produto apresentou teor de proteínas preconizado pela legislação além de gordura, minerais e elevada atividade antioxidante devido à adição de luteína, ou seja, o produto mostrou-se nutricionalmente superior se comparada à outras bebidas carbonatadas (como refrigerantes). A bebida láctea desenvolvida possui baixo custo de fabricação podendo agregar valor ao soro e permitindo o seu uso adequado e sustentável por parte das indústrias de laticínios. / The whey, from the production of various cheeses, it is still a serious problem in the dairy industry, with a view to its disposal have a negative impact on the environment and treatment sometimes becomes uneconomic. Given the above, this work aims to produce an acidified milk drink, flavored, carbonated and enriched with lutein. In order to make this product available in the dairy industry, with protein, vitamins and minerals, for the manufacture of a refreshing drink, due to the added CO2 and considered functional use, once it has been added lutein extract. The whey for the manufacture of the drink was obtained from the manufacture of Minas Frescal cheese. The product was produced in 4 replicates and each replicate was analyzed over a maximum period of 120 days, the two treatments being applied: under refrigeration and at room temperature. The product had physical chemical and microbiological stability during the storage time (120 days) at different temperatures, showing no count of microorganisms, confirming the effectiveness of the microbiological barrier (pH, CO2 and heat treatment). The sensory analysis showed that the product had good acceptance and that the most widely accepted is the one stored under refrigeration, and the acceptance was inversely proportional to the storage time, and the viscosity increased slightly as a function of storage time for the product kept under refrigeration. The lutein extract was added to the product in order to increase its antioxidant activity, which can help strengthen the forming fabric of the eye macula, preventing degeneration and increasing their resistance against diseases. The product showed levels of protein according to the legislation, fat and minerals, in addition to high antioxidant activity due to the addition of lutein. The product was found to be nutritionally superior if compared to other carbonated drinks (such as soda). The developed milk drink has low manufacturing cost and can add value to the whey and allowing its proper and sustainable use by the dairy industry.
527

Diffusion-weighted MRI and delayed contrast enhancement of degenerated intervertebral disc

Niinimäki, J. (Jaakko) 01 September 2009 (has links)
Abstract Magnetic resonance imaging (MRI) provides methods to study the microstructure and functional properties of tissues that can be utilized to acquire information about the degenerative processes in the spine. The purpose of the current study was to evaluate the value of diffusion-weighted MRI and quantification of delayed gadolinium enhancement in assessing intervertebral disc degeneration. An experimental degeneration model was used to evaluate the sensitivity of diffusion-weighted MRI and T2 relaxation time measurements in detecting early degenerative changes in the disc. In six pigs, an annular disc lesion was induced surgically, after which the discs were repeatedly MR imaged for up to eight weeks. T2 relaxation time of the lesioned discs decreased postoperatively, whereas apparent diffusion coefficient (ADC) initially increased, but at eight weeks decreased when compared to the control discs. The value of ADC in degeneration of human discs was evaluated by imaging 228 voluntary middle-aged men. ADC values of the three lowest lumbar intervertebral discs were measured and disc degeneration was visually graded. The reduction in ADC between visually normal and moderately degenerated discs was 4%, whereas severely degenerated discs showed 5% higher ADC values than normal discs. T2 signal intensity of the discs was significantly correlated with the ADC values. Because of a considerable overlap between ADC values of normal and degenerated discs the clinical relevance of the ADC measurements of lumbar intervertebral discs remains questionable. A method to quantify delayed enhancement of the nucleus pulposus after intravenous gadolinium contrast agent injection was developed to evaluate the diffusion of small solutes into the disc. Twenty male volunteers were imaged in order to correlate the measured change in the T1 relaxation rate with visually evaluated degenerative changes. The percentual change of T1 relaxation rate for individual discs was up to 126%, and a positive trend was observed between the delayed enhancement and the disc degeneration grades. In order to study the factors that determine the intensity of delayed enhancement, T1 relaxation rate measurements were further correlated with lumbar artery stenosis, bone marrow changes adjacent to endplates, endplate defects, and ADC of the disc. Lumbar artery stenosis and ADC values of the discs were not correlated with enhancement, while disc space narrowing and the presence of degenerative endplate changes had a strong correlation, suggesting an important role for the endplate in maintaining the integrity of the disc.
528

Association of impaired blood supply with painful lumbar disc degeneration

Kurunlahti, M. (Mauno) 23 May 2003 (has links)
Abstract The purpose of this study was to evaluate the role of diminished arterial blood flow in painful disc degeneration. Diffusion in intervertebral discs of 37 asymptomatic adults measured by magnetic resonance imaging (MRI) and their lumbar arterial blood supply measured by magnetic resonance angiography (MRA) correlated significantly. End plate degeneration in intervertebral discs evaluated with MRI was analysed with reference to disc distress evaluated with computed tomography (CT) discography, and a significant correlation between end plate degeneration and disc degeneration was found among 36 low back pain patients. Intradiscal pain caused by discography did not correlate with end plate degeneration. There were significantly more atheromatous plaques in the abdominal aorta among 29 chronic low back pain patients compared to 52 asymptomatic people, especially in the age group under 50 years. Occlusion of lumbar arteries in MRA correlated significantly with disc degeneration in MRI among 113 sciatica patients. Furthermore, the disc degeneration and the occlusion of lumbar arteries were severe among 41 sciatica patients and 41 asymptomatic people. During a three-year follow-up, the occlusion of lumbar arteries in MRA correlated significantly with physical and mental ability measured by a self-efficacy questionnaire at every assessment point (1,2,3 years). Furthermore, the intensity of back pain at 1 year and leg pain at 2 years correlated with the occlusion of lumbar arteries. Re-stenosis of lumbar arteries within 3 years correlated significantly with medical consultations for low back pain, prolonged low back pain and prolonged sciatica during one year before the baseline assessment.
529

The heritability and morphology of lumbar Modic changes and their association with pain

Määttä, J. (Juhani) 15 November 2016 (has links)
Abstract Low back pain (LBP) causes enormous costs to society. Certain magnetic resonance imaging (MRI) findings, including disc degeneration and disc herniation, have been associated with LBP in epidemiologic studies. Even though LBP should be considered a biopsychosocial condition, there is a need to define the possible existence of specific pathological conditions beyond LBP. One of these possible conditions is Modic change (MC). Modic changes are subchondral and vertebral bone marrow changes revealed by MRI. Although their association with LBP has been previously studied, some results remain contradictory, and we need to explore MC more thoroughly and to determine whether they are a feature of intervertebral disc degeneration or whether they exist in isolation. Moreover, it is unknown whether heritability is a contributing factor to MC. This study explored the heritability and morphology of MC and their association with severe, prolonged and disabling LBP. The data consisted of two general population samples, TwinsUK from the United Kingdom (mainly female), and the Hong Kong Disc Degeneration Cohort (HKDDC) from Hong Kong, China. The TwinsUK sample included a longitudinal ten-year follow-up, whereas the HKDDC sample was cross-sectional. The heritability of MC was found to be 30%. Modic changes were associated with other MRI findings such as disc degeneration, disc displacement and Schmorl’s nodes. A greater size of MC increased these associations. Type 1 MC were more strongly associated with disc displacement and disc degeneration than Modic type 2 change. Modic changes appeared to be independently associated with disabling LBP; severe, prolonged LBP; and back-related disability. Posterior MC and MC in the whole antero-posterior (AP) length of the vertebral body were more strongly associated with severe, prolonged LBP than other MC. A greater number and size of MC increased this association. In terms of disc degeneration, MC were independently associated with loss of disc height and disc signal intensity. Incident MC were independently associated with loss of disc height and disc bulge in a ten-year follow-up. Modic changes are heritable, and are associated with severe and disabling LBP. The location, size and number of MC affect the association of MC with other MRI findings, LBP and back-related disability. / Tiivistelmä Alaselkäkivusta aiheutuu valtavat kustannukset yhteiskunnalle. Tietyt magneettikuvauslöydökset, kuten välilevyrappeuma ja välilevytyrä, on yhdistetty alaselkäkipuun epidemiologisissa tutkimuksissa. Alaselkäkipua arvioidaan yleensä biopsykososiaalisen mallin avulla, koska sen syytekijät tunnetaan huonosti. Lannerangan Modic-muutoksia pidetään yhtenä mahdollisena alaselkäkivun syytekijänä. Modic-muutokset ovat rustonalaisia, nikaman luuytimen muutoksia, jotka näkyvät magneettikuvantamisella. Tulokset Modic-muutosten ja alaselkäkivun yhteydestä ovat kuitenkin ristiriitaisia. Modic-muutosten sijainnin, koon ja muodon vaikutus alaselkäkipuun tunnetaan edelleen puutteellisesti. Lisäksi niiden perinnöllisyys on epäselvä. Tässä tutkimuksessa tarkasteltiin Modic-muutosten perinnöllisyyttä ja tarkempaa morfologiaa, kuten sijaintia ja kokoa lannerangassa, sekä selvitettiin niiden yhteyttä haittaavaan ja voimakkaaseen alaselkäkipuun. Tutkimus perustui kahteen väestöperäiseen aineistoon: TwinsUK-kaksosaineistoon (pääosin naisia) Yhdistyneistä kuningaskunnista ja Hong Kong Disc Degeneration -kohorttiin Hongkongista, Kiinasta. TwinsUK-aineisto sisälsi seurantatietoja 10 vuoden ajalta, ja Hongkongin aineisto oli kerätty yhdestä aikapisteestä. Modic-muutosten perinnöllisen osuuden todettiin olevan 30 %. Modic-muutokset olivat yhteydessä muihin magneettikuvauslöydöksiin kuten välilevyrappeumaan, välilevypullistumaan ja Schmorlin keräsiin. Tyypin 1 Modic-muutokset olivat voimakkaammin yhteydessä välilevypullistumiin ja -rappeumaan kuin tyypin 2 muutokset. Modic-muutokset olivat yhteydessä toimintakykyä alentavaan ja voimakkaaseen, pitkittyneeseen alaselkäkipuun. Koko nikaman läpimitan käsittävät ja nikaman takaosassa sijaitsevat muutokset olivat voimakkaammin yhteydessä alaselkäkipuun. Muutosten suurempi koko ja yhteislukumäärä lannerangassa voimistivat sen yhteyttä alaselkäkipuun. Modic-muutokset olivat yhteydessä välilevyn madaltumiseen ja signaali-intensiteetin laskuun. Kymmenen vuoden seuranta-aikana ilmaantuneet Modic-muutokset olivat yhteydessä välilevyn madaltumiseen ja välilevypullistumaan. Modic-muutokset ovat perinnöllisiä ja ne ovat yhteydessä voimakkaaseen sekä toimintakykyä heikentävään alaselkäkipuun. Muutosten tyypin lisäksi niiden sijainti, koko ja lukumäärä tulee huomioida alaselkäkipua arvioitaessa.
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Cognitive and behavioral characteristics of frontotemporal lobar degeneration

Suhonen, N. M. (Noora- Maria) 29 August 2017 (has links)
Abstract Frontotemporal lobar degeneration (FTLD) is the second commonest cause of dementia after Alzheimer’s disease (AD) in patients &lt;65 years. Its most frequent clinical subtype is behavioral variant frontotemporal dementia (bvFTD) characterized by behavioral change and executive deficits. FTLD also encompasses two variants of primary progressive aphasia (PPA) characterized by language deficits. The majority of familial FTLD cases are linked to the C9ORF72 expansion mutation. As both cognitive and behavioral changes are core diagnostic features of FTLD, neuropsychological assessment is vital. However, neuropsychological literature is inconclusive regarding the most functional measures for detecting FTLD. Current knowledge on the cognitive profile of patients with the C9ORF72 expansion is scarce. The aims of this thesis were threefold: (1) to identify the cognitive measures that optimally serve the differential diagnosis of FTLD, (2) to characterize the neuropsychological profile of C9ORF72 expansion; and (3) to examine the utility of the Modified Frontal Behavioral Inventory (FBI-mod) in differentiating FTLD, AD, and mild cognitive impairment (MCI). The participants comprised FTLD, AD, and MCI patients diagnosed in the University Hospitals of Oulu and Kuopio. The patients underwent a detailed neuropsychological assessment including the CERAD neuropsychological battery (CERAD-NB) and the FBI-mod. While bvFTD was characterized by verbal fluency, working memory, and verbal comprehension deficits relative to AD, AD was associated with greater episodic memory impairments. The poorer delayed recall in AD was further evident on the memory tests of the CERAD-NB; however, its overall utility in the differentiation between FTLD and AD was limited. The C9ORF72 expansion carriers showed more severe executive deficits than non-carriers. The C9ORF72 expansion may further be associated with slowly progressing FTLD. On the FBI-mod, bvFTD was linked to amplified behavioral symptoms relative to AD, MCI, and PPA. Findings highlight the importance of incorporating a broad cognitive battery in the neuropsychological evaluation of FTLD. Though the clinical phenotype of C9ORF72 expansion appears broad, executive impairment likely is a core feature of bvFTD patients with the expansion. The use of the FBI-mod is recommended as a structured measure for behavioral symptoms of bvFTD. / Tiivistelmä Otsa-ohimolohkorappeumat on Alzheimerin taudin (AT) jälkeen yleisin työikäisten dementiaa aiheuttava sairausryhmä. Sen yleisin alamuoto on otsalohkodementia, jonka ensioireita ovat käyttäytymisen muutokset ja toiminnanohjauksen ongelmat. Sairausryhmään kuuluu myös kaksi kielellisin oirein ilmenevää alatyyppiä. C9ORF72-toistojaksomutaation on todettu selittävän suurimman osan perinnöllisistä tapauksista. Kognitiivisten ja käyttäytymiseen liittyvien muutosten arvioiminen on keskeinen osa taudin diagnostiikkaa. Tutkimustiedon perusteella on epäselvää, mitkä neuropsykologiset menetelmät soveltuvat parhaiten otsa-ohimolohkorappeumien tunnistamiseen. Tieto C9ORF72-mutaation kantajien kognitiivisesta profiilista on niukkaa. Tutkimuksen tavoitteena oli löytää neuropsykologisia menetelmiä, joista on hyötyä otsa-ohimolohkorappeumien erotusdiagnostiikassa ja selvittää C9ORF72-mutaation kantajien neuropsykologisia erityispiirteitä. Lisäksi haluttiin tutkia käytösoireita kartoittavan FBI-mod -läheiskyselyn hyödyllisyyttä otsa-ohimolohkorappeumien, AT:n ja lievän kognitiivisen heikentymän (MCI) erottamisessa. Aineisto koostui Oulun ja Kuopion yliopistosairaaloissa diagnosoiduista otsa-ohimolohkorappeuma-, AT- ja MCI-potilaista, joille oli tehty CERAD-tehtäväsarja, laaja neuropsykologinen tutkimus sekä FBI-mod. Otsalohkodementiaa sairastavat suoriutuivat AT-potilaita heikommin sanasujuvuutta, työmuistia ja kielellistä käsityskykyä arvioivissa tehtävissä, kun taas tapahtumamuisti oli heikompi AT:a sairastavilla. Myös CERAD-tehtäväsarjassa AT-potilaat suoriutuivat heikommin viivästetyn mieleenpalautuksen tehtävissä, mutta kokonaisuutena tehtäväsarjan kyky erotella otsa-ohimolohkorappeumaa ja AT:a sairastavat oli rajallinen. C9ORF72-mutaation kantajilla toiminnanohjauksen ongelmat olivat vaikeampia kuin ei-kantajilla. Lisäksi havaittiin, että C9ORF72-mutaatioon liittyvä sairaus voi edetä hyvin hitaasti. FBI-mod erotteli hyvin otsalohkodementiaa sairastavat AT- ja MCI-potilaista sekä otsa-ohimolohkorappeumien kielellistä muotoa sairastavista. Tulokset korostavat laajan neuropsykologisen tutkimuksen merkitystä otsa-ohimolohkorappeumien diagnostiikassa. Vaikka C9ORF72-mutaation kliininen kuva on vaihteleva, ovat toiminnanohjauksen ongelmat keskeinen osa taudinkuvaa. FBI-mod -kyselyn käyttö on suositeltavaa otsalohkodementiaan liittyvien käytösoireiden strukturoidussa arvioinnissa.

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