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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.
81

Análise do consumo de extato hidrossolúvel de soja na qualidade do tecido ósseo de ratos jovens adultos / Analysis of soybean´s hydro soluble extact on the quality of the bone tissue of young adults rats

Andrade, Carolina de Matos Figueiredo de [UNESP] 18 January 2016 (has links)
Submitted by CAROLINA DE MATOS FIGUEIREDO null (carolinaf.nutri@hotmail.com) on 2016-01-24T19:05:39Z No. of bitstreams: 1 Dissertação PDF.pdf: 691008 bytes, checksum: 2cf64d69340e51ebd81408264bdb85d9 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-01-25T16:38:45Z (GMT) No. of bitstreams: 1 andrade_cmf_me_araca.pdf: 691008 bytes, checksum: 2cf64d69340e51ebd81408264bdb85d9 (MD5) / Made available in DSpace on 2016-01-25T16:38:45Z (GMT). No. of bitstreams: 1 andrade_cmf_me_araca.pdf: 691008 bytes, checksum: 2cf64d69340e51ebd81408264bdb85d9 (MD5) Previous issue date: 2016-01-18 / A soja é uma leguminosa rica em proteínas, fonte de cálcio e isoflavonas. Um dos possíveis efeitos das isoflavonas é de reduzir a perda óssea quando há uma deficiência de estrogênio. A proposta desse estudo foi analisar a influência da dieta suplementada com extrato hidrossolúvel de soja (EHS) na massa óssea de ratos adultos jovens de ambos os sexos. Foram utilizados 40 ratos Novergicus Albinus linhagem Wistar adultos jovens e saudáveis, aleatoriamente separados em quatro grupos: macho controle (MC), macho suplementado (MS), fêmea controle (FC) e fêmea suplementada (FS) que permaneceram por 11 semanas em gaiola comum recebendo 500 mL de água e 300g de ração diariamente, os grupos suplementados (MS e FS), ao qual foi oferecido além de água e ração, 500 ml de EHS, durante o mesmo período experimental do controle. O consumo de ração e a ingestão de líquidos foram mensurados, bem como a massa dos animais. Ao final do período os animais foram eutanasiados. Os ossos foram submetidos à densitometria óssea– DXA (osso inteiro e região cortical) e ensaio mecânico, para avaliação da densidade mineral óssea - DMO (g/cm2), Força Máxima (N) e Rigidez (kN/m). Na análise de grau de mineralização foi utilizado as cinzas para quantificar de concentração de cálcio e fósforo. O consumo de EHS provocou diminuição da DMO no grupo MS, porém não houve alteração nas propriedades biomecânicas, força máxima e rigidez. A concentração de cálcio e fósforo nas cinzas dos fêmures do grupo MS foi significantemente menor que o grupo controle. Conclui-se assim, que o extrato hidrossolúvel de soja influenciou negativamente o conteúdo mineral ósseo de ratos machos jovens adultos diminuindo a mineralização, sem alterar as características mecânicas. / Soybeans are a rich legume protein, a source of calcium and isoflavones. One of the possible effects of isoflavones is to reduce bone loss when it was estrogen deficiency. The purpose of this study was to analyze the influence of diet supplemented with soybean’s hydro soluble extract (SHE) in bone mass in young adults rats of both genders. Were used 40 rats Novergicus Albinus Wistar young and healthy, randomly separated into four groups: male control (MC) and female control(FC), which remained for 11 weeks in common cage receiving 500 ml of water and 300 g of feed daily, and the others supplemented groups; male supplemented (MS) and female supplemented, that was offered in addition to water and feed 500ml of SHE. During the experimental period, feed intake and intake of liquids were measured as well as the mass of animals. At the end, the animals were euthanized. The bones underwent bone densitometry – DXA(whole bone and cortical area) and mechanical testing for bone mineral density - BMD (g / cm 2) Maximum Strength (N) and stiffness (kN / m), respectively. To analyze the mineralization degree was used bone ashes to quantify calcium and phosphorus concentration. The consumption of SHE caused decreased of BMD in MS group, but there were no changes in the bone biomechanical properties, maximum strength and rigidity. Concluding that the water extract of soy beans negatively affected the bone mineral content of young adult males rats decreasing the mineralization degree without changing the mechanical characteristics.
82

Estudo de densiometria óssea de cães SRD com propriedades físicas e químicas

Grossklauss, Dany Bruno Borella dos Santos [UNESP] 31 October 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-10-31Bitstream added on 2014-06-13T19:28:41Z : No. of bitstreams: 1 grossklauss_dbbs_me_botib.pdf: 317271 bytes, checksum: 8e3c70720316db38477d53932edfcfa5 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Existem enfermidades em animais vertebrados associadas à estrutura do tecido ósseo que afetam diretamente o sistema locomotor do animal. Tratando-se de um endo-esqueleto, o diagnóstico dessas patologias torna-se abstruso in vivo. A caracterização física da estrutura do tecido ósseo de animais sadios torna-se uma grande ferramenta no diagnóstico comparativo de animais vivos. Existem várias técnicas para determinação da densidade mineral óssea, e uma delas que merece destaque é a densitometria óptica; que vem desenvolvendo muito com o avanço da informática e possui um baixo custo. O objetivo desse trabalho foi avaliar e discutir a metodologia da densitometria óptica, realizando uma comparação com o método de imersão em água. O método de imersão em água também foi utilizado para avaliar os efeitos do peso, sexo e idade do grupo de animais na densidade mineral óssea de cães sem raça definida (SRD). As amostras foram cedidas pelo Departamento de Patologia da Faculdade de Medicina Veterinária e Zootecnia de Botucatu-SP e pelo canil municipal da cidade de Araras, sendo de cães machos e fêmeas. Foram utilizadas as partes dos membros anteri-ores direitos da região da articulação úmero-rádio-ulnar de cada animal e submetidas aos métodos citados acima para obtenção da densidade mineral óssea. Posteriormente as amostras foram moídas para a realização da análise química para a determinação das concentrações de cálcio nessas amostras e determinar-se uma possível correlação com a densidade óssea. O trabalho apresentou para densidade mineral óssea média em cães SRD um va-lor de 3,080 ± 0,582 milímetros de alumínio para o método de densitometria óptica e de 1,630 ± 0,125 g/cm3 para... / There are some diseases in vertebrates associated with the structure of bone tissue that directly affect the locomotor system of the animal. In the case of an endoskeleton, the diagnosis of these diseases becomes abstruse “in vivo”. The characterization of the physical structure of the bone tissue of healthy animals becomes a great tool in comparative diagnosis in live animals. There are several techniques for determining bone mineral density, and one that deserves mention is the optical density. It is a technique that has been developing a lot with the advancement of information technology and has a low cost. The objective of this study was to evaluate and discuss the methodology of optical density, doing a comparison with the method of immersion in water. The water im-mersion method was also used to further evaluate the effect of weight, sex and age on bone mineral density of mongrel dogs. The samples were provided by the Department of Pathology, Faculty of Veteri-nary Medicine of Botucatu and the kennel in the city of Araras, being male and female dogs. Were used the share rights of former members of the joint area humerus radio-ulnar of each animal and subjected to the above methods to obtain bone mineral density. Subsequently, the samples were ground for holding the chemical analysis for the deter-mination of calcium concentrations in these samples and to determine a possible corre-lation with bone density. The work presented for average bone mineral density in mongrel dogs a value of 3.080 ± 0.582 mm aluminum for the method of optical densitometry and 1.630 ± 0.125 g/cm3 for the immersion method, and the correlation between the methods given by the following equation: y = 0.197 x + 0.824, and bone mineral density in millimeters of aluminum is represented by... (Complete abstract click electronic access below)
83

Estudo de densiometria óssea de cães SRD com propriedades físicas e químicas /

Grossklauss, Dany Bruno Borella dos Santos. January 2011 (has links)
Orientador: Joel Mesa Hormaza / Coorientador: Marcos Antonio de Rezende / Banca: Paulo Roberto Rodrigues Ramos / Banca: Vânia Maria Vasconcelos Machado / Resumo: Existem enfermidades em animais vertebrados associadas à estrutura do tecido ósseo que afetam diretamente o sistema locomotor do animal. Tratando-se de um endo-esqueleto, o diagnóstico dessas patologias torna-se abstruso in vivo. A caracterização física da estrutura do tecido ósseo de animais sadios torna-se uma grande ferramenta no diagnóstico comparativo de animais vivos. Existem várias técnicas para determinação da densidade mineral óssea, e uma delas que merece destaque é a densitometria óptica; que vem desenvolvendo muito com o avanço da informática e possui um baixo custo. O objetivo desse trabalho foi avaliar e discutir a metodologia da densitometria óptica, realizando uma comparação com o método de imersão em água. O método de imersão em água também foi utilizado para avaliar os efeitos do peso, sexo e idade do grupo de animais na densidade mineral óssea de cães sem raça definida (SRD). As amostras foram cedidas pelo Departamento de Patologia da Faculdade de Medicina Veterinária e Zootecnia de Botucatu-SP e pelo canil municipal da cidade de Araras, sendo de cães machos e fêmeas. Foram utilizadas as partes dos membros anteri-ores direitos da região da articulação úmero-rádio-ulnar de cada animal e submetidas aos métodos citados acima para obtenção da densidade mineral óssea. Posteriormente as amostras foram moídas para a realização da análise química para a determinação das concentrações de cálcio nessas amostras e determinar-se uma possível correlação com a densidade óssea. O trabalho apresentou para densidade mineral óssea média em cães SRD um va-lor de 3,080 ± 0,582 milímetros de alumínio para o método de densitometria óptica e de 1,630 ± 0,125 g/cm3 para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: There are some diseases in vertebrates associated with the structure of bone tissue that directly affect the locomotor system of the animal. In the case of an endoskeleton, the diagnosis of these diseases becomes abstruse "in vivo". The characterization of the physical structure of the bone tissue of healthy animals becomes a great tool in comparative diagnosis in live animals. There are several techniques for determining bone mineral density, and one that deserves mention is the optical density. It is a technique that has been developing a lot with the advancement of information technology and has a low cost. The objective of this study was to evaluate and discuss the methodology of optical density, doing a comparison with the method of immersion in water. The water im-mersion method was also used to further evaluate the effect of weight, sex and age on bone mineral density of mongrel dogs. The samples were provided by the Department of Pathology, Faculty of Veteri-nary Medicine of Botucatu and the kennel in the city of Araras, being male and female dogs. Were used the share rights of former members of the joint area humerus radio-ulnar of each animal and subjected to the above methods to obtain bone mineral density. Subsequently, the samples were ground for holding the chemical analysis for the deter-mination of calcium concentrations in these samples and to determine a possible corre-lation with bone density. The work presented for average bone mineral density in mongrel dogs a value of 3.080 ± 0.582 mm aluminum for the method of optical densitometry and 1.630 ± 0.125 g/cm3 for the immersion method, and the correlation between the methods given by the following equation: y = 0.197 x + 0.824, and bone mineral density in millimeters of aluminum is represented by... (Complete abstract click electronic access below) / Mestre
84

Análise do consumo de extato hidrossolúvel de soja na qualidade do tecido ósseo de ratos jovens adultos /

Andrade, Carolina de Matos Figueiredo de. January 2016 (has links)
Orientador: Mario Jefferson Quirino Louzada / Banca: Paulo César Ciarlini / Banca: Cáris Maroni Nunes / Resumo: A soja é uma leguminosa rica em proteínas, fonte de cálcio e isoflavonas. Um dos possíveis efeitos das isoflavonas é de reduzir a perda óssea quando há uma deficiência de estrogênio. A proposta desse estudo foi analisar a influência da dieta suplementada com extrato hidrossolúvel de soja (EHS) na massa óssea de ratos adultos jovens de ambos os sexos. Foram utilizados 40 ratos Novergicus Albinus linhagem Wistar adultos jovens e saudáveis, aleatoriamente separados em quatro grupos: macho controle (MC), macho suplementado (MS), fêmea controle (FC) e fêmea suplementada (FS) que permaneceram por 11 semanas em gaiola comum recebendo 500 mL de água e 300g de ração diariamente, os grupos suplementados (MS e FS), ao qual foi oferecido além de água e ração, 500 ml de EHS, durante o mesmo período experimental do controle. O consumo de ração e a ingestão de líquidos foram mensurados, bem como a massa dos animais. Ao final do período os animais foram eutanasiados. Os ossos foram submetidos à densitometria óssea- DXA (osso inteiro e região cortical) e ensaio mecânico, para avaliação da densidade mineral óssea - DMO (g/cm2), Força Máxima (N) e Rigidez (kN/m). Na análise de grau de mineralização foi utilizado as cinzas para quantificar de concentração de cálcio e fósforo. O consumo de EHS provocou diminuição da DMO no grupo MS, porém não houve alteração nas propriedades biomecânicas, força máxima e rigidez. A concentração de cálcio e fósforo nas cinzas dos fêmures do grupo MS foi signific... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Soybeans are a rich legume protein, a source of calcium and isoflavones. One of the possible effects of isoflavones is to reduce bone loss when it was estrogen deficiency. The purpose of this study was to analyze the influence of diet supplemented with soybean's hydro soluble extract (SHE) in bone mass in young adults rats of both genders. Were used 40 rats Novergicus Albinus Wistar young and healthy, randomly separated into four groups: male control (MC) and female control(FC), which remained for 11 weeks in common cage receiving 500 ml of water and 300 g of feed daily, and the others supplemented groups; male supplemented (MS) and female supplemented, that was offered in addition to water and feed 500ml of SHE. During the experimental period, feed intake and intake of liquids were measured as well as the mass of animals. At the end, the animals were euthanized. The bones underwent bone densitometry - DXA(whole bone and cortical area) and mechanical testing for bone mineral density - BMD (g / cm 2) Maximum Strength (N) and stiffness (kN / m), respectively. To analyze the mineralization degree was used bone ashes to quantify calcium and phosphorus concentration. The consumption of SHE caused decreased of BMD in MS group, but there were no changes in the bone biomechanical properties, maximum strength and rigidity. Concluding that the water extract of soy beans negatively affected the bone mineral content of young adult males rats decreasing the mineralization degree without c... (Complete abstract click electronic access below) / Mestre
85

Caracterização eletroforética de proteínas musculares de aves de interesse comercial /

Figueira, Paulo Tadeu. January 2011 (has links)
Resumo: Na busca pela excelência sensorial de um produto, as características exigidas pelo consumidor são a maciez, a suculência e o odor, que estão diretamente ligadas a constituição proteica do produto, juntamente com os lipídeos e os carboidratos. Atualmente, o consumo de produtos cárneos no Brasil encontrase em constante crescimento, sendo que os de origem avícola são os principais expoentes. Para a análise da qualidade dos produtos, a avaliação da origem das proteínas musculares é fator de grande importância e algumas das técnicas que podem ser citadas para sua avaliação e quantificação são as técnicas eletroforéticas e densitométricas, muito utilizadas hoje como padrão para diversas pesquisas em alimentos. Para realização deste trabalho, partiuse de que as proteínas musculares de frangos, perus e avestruzes apresentam diferentes características estruturais devido à expressão gênica e suas estruturas primárias podem ser identificadas por técnicas eletroforéticas e, através da densitometria, quantificadas. Foram colhidos fragmentos de musculo peitoral de 10 aves de cada espécie abatidas em frigoríficos inspecionados. Realizou-se a extração proteica por maceração e centrifugação dos fragmentos, e posterior submissão a quatro técnicas eletroforéticas sendo elas a Eletroforese Nativa em Gel de Poliacrilamida, SDS-PAGE Não Denaturante, CELM-GEL® - Filme de Agarose Geral e Isoeletrofocalização em Phast-Gel. Os resultados obtidos demonstraram a obtenção de um padrão proteico para as espécies em estudo, podendo utilizá-las para diferenciação das espécies e com a densitometria demonstrou a ocorrência de variações quantitativas individuais que não comprometeram a padronização específica dos eletroferogramas / Abstract: In pursuit of a sensory product excellence, the characteristics required by consumers are tenderness, juiciness and smells, and all then linked directly to protein constitution of the product, along with lipids and carbohydrates. Currently, the consumption of meat products in Brazil is constantly growing, and the poultry origins are the main exponents. For the quality analysis of product, the evaluation of the origin of the proteins muscles is a factor of great importance and some of the techniques can be cited for their evaluation and quantification are the electrophoretic and densitometric techniques, widely used today as a standard for research on all food. For this study, we started with the muscle proteins of chickens, turkeys and ostriches have different characteristics due to structural gene expression and their primary structures be identified by electrophoretic techniques and by densitometry, it is quantified. Fragments from pectoral muscle were collected front of 10 birds of each species slaughtered in abattoirs inspected. The protein extraction was carried out by the maceration and centrifugation the fragments, and subsequent submission to four electrophoretic techniques with them: the Native Gel Electrophoresis, Polyacrylamide, SDS-PAGE not Denaturant, CELM-GEL ® - Film Agarose General and IEF in Phast-gel. The results obtained demonstrate the attainment of a standard protein for the species under review and may use them for differentiation of species and densitometry demonstrated the occurrence of individual quantitative variations did not affect the specific standardization of electropherograms / Orientador: Roberto de Oliveira Roça / Coorientador: Paulo Roberto Rodrigues Ramos / Banca: Germano Francisco Biondi / Banca: Nelson Massaru Fukumoto / Mestre
86

Correlação entre fatores de qualidade ossea mandibular e densidade ossea mineral em mulheres brasileiras / Correlation between mandibular bone quality factors and bone mineral density in brazilian women

Pedrosa, Esio Fortaleza Nascimento Chaves 13 August 2018 (has links)
Orientador: Plauto Christopher Aranha Watanabe / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-13T08:02:53Z (GMT). No. of bitstreams: 1 Pedrosa_EsioFortalezaNascimentoChaves_M.pdf: 2734521 bytes, checksum: ab04697c2441e91af05be90051625d6d (MD5) Previous issue date: 2009 / Resumo: Existem diversos métodos para avaliar a qualidade óssea através de sua densidade. Estes métodos variam no custo, disponibilidade e na dose de radiação. O cirurgião-dentista atua nos elementos dentários e nas estruturas de suporte dos maxilares e mandíbula, componentes do sistema estomatognático. Nas últimas décadas têm se pesquisado muito a respeito da qualidade óssea das estruturas de suporte dos elementos dentários, principalmente na mandíbula, com convincentes evidências de perda óssea bucal associada com a osteoporose, particularmente um aumento da porosidade cortical do osso alveolar e corpo mandibular. O Objetivo deste estudo foi avaliar a correlação de três aspectos da qualidade óssea mandibular, em radiografias panorâmicas, correlacionando-os com medidas de densidade óssea mineral (DOM) do DEXA realizados no radio, coluna e fêmur. Os resultados apresentaram correlação significante entre a classificação morfológica do córtex (CC) e a espessura da cortical basal mandibular com a DOM. Não houve correlação entre os fatores dimensão fractal (DF) e porcentagem de pixels pretos (ET) com a DOM. Pode-se concluir que é possível referenciar pacientes para o DEXA com a finalidade de pesquisar a baixa massa óssea mineral pelas análises da cortical inferior da mandíbula. / Abstract: There are several methods to evaluate the bone quality by the density. These methods vary in cost, availability and the radiation dose. The dentist works on teeth and in the maxilla and mandible support structures, components of the stomatognathic system. Recently, it has been searched too much about the bone quality of the teeth support structures, especially in the jaw with evidences of oral bone loss associated with osteoporosis, particularly an increase in cortical porosity of the alveolar bone and mandibular body. The aim of this study was to evaluate the interrelationship of three aspects of mandibular bone quality on panoramic radiographs, correlating them with measures of bone mineral density (BMD) of DEXA performed in radio, spine and femur. The results showed a significant correlation between the cortex morphological classification and cortex thickness with lower BMD. There was no correlation between the fractal dimension (FD) factors and black pixels (ET) percentage with the BMD. It could be concluded that it is possible to refer patients for DEXA in order to search for low bone mineral analysis of the lower mandibular cortex. / Mestrado / Radiologia Odontologica / Mestre em Radiologia Odontológica
87

Correlação do risco de fratura osteoporótica em 10 anos calculado pelo FRAX com e sem densitometria em mulheres brasileiras na pós menopausa = Correlation between osteoporotic fracture risk in 10 years calculated by FRAX with and without bone densitometry in post menopause brazilian women / Correlation between osteoporotic fracture risk in 10 years calculated by FRAX with and without bone densitometry in post menopause brazilian women

Bastos-Silva, Yasmin, 1990- 27 August 2018 (has links)
Orientador: Lúcia Helena Simões da Costa Paiva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-27T21:42:31Z (GMT). No. of bitstreams: 1 Bastos-Silva_Yasmin_M.pdf: 1080942 bytes, checksum: 7599dbea7c337dddf84a74226180fc92 (MD5) Previous issue date: 2015 / Resumo: O risco de fratura osteoporótica pode ser avaliado clinicamente baseado em fatores clínicos e pela densidade mineral óssea (DMO), entretanto esses parâmetros não são bons preditores do risco de fratura. Recentemente, o Brasil foi incluído no instrumento fracture risk assessment tool- FRAX-BRASIL, porém seu uso tem sido limitado na prática clínica. OBJETIVO: Avaliar o grau de concordância entre o risco de fratura em 10 anos calculado pelo FRAX-BRASIL com e sem densitometria em mulheres brasileiras na pós-menopausa. MÉTODO: Realizou-se um estudo de corte transversal no período de novembro de 2014 a fevereiro de 2015, com 402 mulheres em acompanhamento no Ambulatório de Menopausa do Hospital da Mulher Prof. Dr. José Aristodemo Pinotti em Campinas-SP. Foram incluídas mulheres com 40 anos ou mais, em amenorreia há pelo menos 12 meses e com exame de densitometria óssea prévio a qualquer tratamento medicamentoso para osteopenia ou osteoporose. As mulheres foram entrevistadas por um pesquisador durante a consulta de rotina, na qual foram coletadas informações sobre fatores de risco necessários para o questionário FRAX-BRASIL e dados da densitometria óssea. Os dados obtidos foram inseridos na plataforma online FRAX-BRASIL, em que foi calculado o risco para uma fratura maior e de quadril, utilizando-se somente os fatores de risco clínicos e o risco incluindo valores de DMO do colo do fêmur em g/cm2. ANÁLISE ESTATÍSTICA: Para análise do grau de concordância entre os riscos de fraturas com e sem densitometria óssea foi utilizado o coeficiente de correlação intraclasse (ICC). O Teste de Mann-whitney foi utilizado para comparação entre as médias do risco de fratura calculado com e sem DMO; para comparação entre as frequências de alto risco calculadas com e sem DMO foi utilizado o Teste de comparação entre duas proporções. Para análise da associação entre as variáveis clinico/demográficas e a variação do risco de fratura foi utilizada a análise de regressão linear. O nível de significância adotado foi <0,05. RESULTADOS: A probabilidade de fratura em 10 anos calculada pelo FRAX-BRASIL para fratura de quadril e para fratura maior somente pelos fatores de risco clínicos foi de 0,84% ±1,92 e 4,03% ±2,98 e com DMO foi de 0,83% ±1,76 e 4,05% ±2,98 respectivamente. O coeficiente de correlação intraclasse entre o FRAX-BRASIL com e sem DMO foi de 0,76 (IC95% 0,716-0,799) para uma fratura maior e de 0,644 (IC95% 0,583-0,698) para fratura de quadril. Ao avaliar as mulheres utilizando o FRAX com DMO 0,75% e 5,22% excederam os limiares de alto risco para fratura maior e de quadril, respectivamente. Sem o acréscimo da densidade óssea 1% e 11,44% apresentaram alto risco para fratura maior e de quadril, respectivamente. Dessa forma a recomendação de tratamento foi concordante entre o FRAX com e sem DMO em 99,75% dos casos de alto risco de fratura maior e de 93,78% para o quadril. Os fatores associados a menor variação FRAX com e sem foram maior idade, menor DMO, menor T-score e ausência de fratura previa tanto para fratura maior como para quadril. O menor IMC esteve associado a menor variação do FRAX apenas para fratura maior. CONCLUSÃO: O risco de fratura maior ou de quadril foi baixo na população estudada. O FRAX-BRASIL apresentou alta concordância para estimar o risco de fratura maior e concordância moderada para fratura de quadril apresentando uma estimativa de risco para fratura semelhante com ou sem DMO em nossa população / Abstract: The risk of osteoporotic fracture can be clinically evaluated based on clinical factors and by the bone mineral density (BMD), but these parameters are not good predictors of fracture risk. Recently, Brazil was included in the fracture risk assessment tool- FRAX-BRAZIL, but its use has been limited in clinical practice. GOAL: To evaluate the degree of correlation between the degree of correlation between the risk of fracture in 10 years calculated by FRAX-BRAZIL with and without densitometry in Brazilian postmenopausal women. METHODS: A cross-sectional study was conducted with 402 women followed up at the Menopause Ambulatory at the Women's Hospital Prof. Dr. José Aristodemo Pinotti in Campinas-SP. Women were included with 40 years or more in amenorrhea for at least 12 months and with bone densitometry exam prior to any drug treatment for osteopenia or osteoporosis. A researcher interviewed the women during a routine visit, where information about risk factors necessary for the FRAX-BRAZIL questionnaire and data of bone densitometry were collected. The collected data were inserted on the online platform FRAX-BRAZIL where the risk for major fractures and of the hip using only clinical risk factors and the risk including femoral neck BMD values in g / cm2. STATISTICAL ANALYSIS: To analyze the degree of correlation between the risk of fractures with and without bone densitometry was used the intraclass correlation coefficient (ICC). The Mann-Whitney test was used to compare the averages of fracture risk calculated with and without BMD; to compare the frequencies of high risk calculated with and without BMD was used the compare Test between two proportions. For analysis of the association between clinical / demographic variables and the change of the fracture risk was used linear regression analysis. The significance level was <0.05. RESULTS: The fracture probability calculated in 10 years by using the FRAX-BRAZIL for hip fracture and major fracture only by clinical risk factors was 0.84% ± 1.92 and 4.03 ± 2.98% and BMD was 0.83% ± 1.76 and 4.05 ± 2.98%, respectively. The intraclass correlation coefficient between the FRAX-BRAZIL with and without BMD was 0.76 (IC95% 0.716-0.799) for a major fracture and 0.644 (IC95% 0.583-0.698) for hip fracture. When evaluating women using FRAX with BMD 0.75% and 5.22% exceeded the high-risk thresholds for major and hip fracture, respectively. Without the increase of the bone density 1% and 11.44% presented high risk for major fractures and of hip, respectively. Then the treatment recommendation was consistent between the FRAX with and without BMD in 99.75% of cases of high risk of major fracture and 93.78% for the hip. Factors associated with less variation FRAX with and without were older, lower BMD, lower T-score, and no previous fracture both for major fracture as to hip fracture. The BMI was associated with lower variation in the FRAX only to major fracture. CONCLUSION: The risk of major fracture or of the hip was low in the study population. The FRAX-BRAZIL presented a high correlation to estimate the risk of major fractures and moderate agreement for hip fracture presenting a risk estimate for similar fracture with or without BMD in our population. The FRAX-BRAZIL presented a high correlation to estimate the risk of major fractures and moderate correlation for hip fracture presenting a risk estimate for similar fracture with or without BMD in our population / Mestrado / Fisiopatologia Ginecológica / Mestra em Ciências da Saúde
88

Mixed-Metal Ruthenium-Platinum Polyazine Supermolecules: Synthesis, Characterization and Exploration of DNA Binding

Milkevitch, Matthew 09 July 2001 (has links)
The goal of this research was to design, prepare and study a new class of supermolecules coupling ruthenium and platinum, which would display covalent binding to DNA. Drawing upon the well-established efficacy of cis-diamminedichloroplatinum(II) (cisplatin) and the DNA-binding properties of select ruthenium polyazine complexes, the approach was to bind the cis-PtIICl2 active site of cisplatin to ruthenium light absorbers using the dpq and dpb bridging ligands (where dpq = 2,3-bis(2-pyridyl)quinoxaline, dpb = 2,3-bis(2-pyridyl) benzoquinoxaline). These complexes are potentially bifunctional, capable of DNA intercalation through the bridging ligand and covalent binding to DNA through the cis-PtCl2 site. Synthetic methods were developed to prepare the mixed-metal, bimetallic complexes [(bpy)2Ru(BL)PtCl2](CF3SO3)2 and [(phen)2Ru(BL)PtCl2](CF3SO3)2 (where bpy = 2,2¢-bipyridine, phen = 1,10-phenanthroline) in high purity and good overall yields. The DNA-binding ability of these complexes was probed by reaction with linearized plasmid DNA and subsequent analysis by native and denaturing gel electrophoresis. The known DNA binders, cisplatin and trans-{[PtCl(NH3)2]2(m-H2N(CH2)6NH2)}(NO3)2 (1,1/t,t), were examined under equivalent conditions and used as positive controls. Native gel electrophoresis was used to show that these complexes strongly bind DNA, retarding the migration of DNA through the gel in a fashion inversely proportional to the ratio of DNA base pairs (bp) to metal complex (mc). Analysis by denaturing gel electrophoresis determined that the Ru-Pt complexes bind to DNA in a fashion similar to cisplatin, forming primarily intrastrand adducts. However, these systems also appear to form interstrand adducts at a 10-fold lower metal concentration than cisplatin. In addition to affecting the migration rate, the bimetallic complexes also significantly reduced the fluorescence of DNA-intercalated ethidium bromide for the Ru-Pt reacted samples at low-DNA bp: mc ratios. This was not observed for the cisplatin and 1,1/t,t treated samples. This observation was quantitated by gel densitometry. Precipitation of the DNA by cisplatin, 1,1/t,t and all four Ru-Pt complexes was determined not to be the cause of reduced ethidium bromide fluorescence intensity. Homogenous solution fluorescence quenching studies have revealed that the Ru-Pt complexes quench the emission of ethidium bromide even in the absence of DNA, whereas cisplatin and 1,1/t,t do not. In order to compare the effects on DNA migration produced by cisplatin, 1,1/t,t and the Ru-Pt complexes, Rf values were calculated. This analysis has revealed that all four Ru-Pt complexes retard DNA migration to approximately the same degree. Calculation of theoretical DNA migration distances, based upon the molecular weight change of DNA caused by metal-complex binding, have revealed that the observed affect on DNA migration cannot be accounted for by an increase in molecular weight alone. This indicates that changes in charge and three-dimensional shape of the DNA upon binding of the Ru-Pt complexes may also contribute. / Ph. D.
89

Changes in bone density in calcium supplemented adolescent female athletes experiencing menstrual dysfunction

Baer, Janine M. January 1988 (has links)
Ph. D. / incomplete_metadata
90

Clinical and phantom-based studies of the validity and value of quantitative radiological hip structural analysis

Khoo, Benjamin Cheng Choon January 2008 (has links)
[Truncated abstract] Areal bone mineral density (BMD) is measured routinely in the clinic by a quantitative radiological technique, dual-energy X-ray absorptiometry (DXA). BMD is used widely to assess non-invasively but indirectly the mechanical fragility of bone and consequently is able to predict fracture risk. While BMD correlates well with in vitro measurements of bone strength it does not directly measure a mechanical property; half of incident minimally traumatic fractures in women occur with BMD values above the World Health Organisation defined threshold for osteoporosis. This arises partly because the mechanical strength of bone is dependent on its structural geometry and material strength as well as bone mineral mass. Essentially, bones fracture when load stresses exceed the mechanical capacity of the material to withstand them. The structural geometry (i.e., the amount of bone tissue and its complex three-dimensional arrangement within the macroscopic bone envelope) defines the stresses produced by a given load, while the intrinsic load capacity of the material is defined by the composition and microstructure of the bone tissue itself. Hip structural analysis (HSA) is a technique that elucidates the structural geometric component of bone strength; essentially combining information available from conventional DXA images of the proximal femur with a biomechanical beam model based on the stresses arising in a combination of pure bending and axial compression. A version of HSA has recently been released commercially, and has obtained US Food and Drug Administration approval for its clinical application. ... Given the acknowledged limitations of the HSA method when applied to 2-D projection images, a 3-D approach to structural geometry, using imaging modalities such as pQCT and QCT or a recently introduced version of DXA that mimics QCT, is indicated for the future. With that in mind and the possibility of the anthropometric phantom being adopted for future accuracy and precision assessments, improvements in the design of this phantom are recommended. Studies to better understand and verify Contents v the relevance of the 'local buckling' phenomenon as a structural geometric factor in the genesis of macro-fractures are also recommended. In summary, it is essential that superior (compared to BMD) non-invasively determined clinical predictors of bone fragility leading to fracture be investigated. Structural geometric variables are potential candidates. This has led to consideration of; (i) the need to progress beyond BMD for a more sensitive and specific bone strength measurement; (ii) theoretical advantages of structural geometry over BMD; (iii) limitations of the current HSA technique based on DXA, including those introduced by its restrictive assumptions; (iv) the value of HSA in longitudinal studies, exemplified by the 'normal' but rapid skeletal changes seen in human lactation, with possible implications for an analogous study of the menopause; and (v) an investigation, using a custom-designed anthropometric phantom, of the adaptation of HSA to certain emerging imaging modalities and methods able to resolve bone structural geometry in three dimensions.

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