Dissertationen: „Bone and Bones – anatomy – histology“

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Xynos, Ioannis D. „Bioactive glasses for the in vitro synthesis of bone tissue“. Thesis, Imperial College London, 2001. http://hdl.handle.net/10044/1/11494.

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Hankey, David Patrick. „Characterisation of osteoblasts in culture and analysis of bone specific proteins“. Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317508.

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Saxena, Anita. „Histological techniques for estimating age at death from human bone : an Indian case study“. Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363129.

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Afzal, Faiza. „The role of nitric oxide in the control of osteoblast metabolism and maintenance of bone integrity“. Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271576.

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Souza, Caio Gonçalves de. „Análise histomorfométrica do colo femoral em pacientes com e sem fratura do colo do fêmur“. Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5140/tde-24012008-142245/.

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Foi analisada a parte trabecular do colo do fêmur de 13 pacientes do sexo feminino, com idade acima dos 60 anos, com o método da histomorfometria óssea. Sete destas pacientes tiveram fratura do colo do fêmur. Todas foram submetidas a artroplastia do quadril. O exame de densitometria óssea não mostrou diferença significativa. Na espessura média das trabéculas não houve diferença significativa, porém o número de trabéculas foi menor e a separação entre elas foi maior no grupo com fraturas.
A histomorphometry evaluation of the trabecular part of the femoral neck was performed in 13 women over 60 years old submitted to hip arthroplasty. Seven of these patients had a femoral neck fracture. The bone mineral density showed no difference between both groups. The average thickness did not have significant between both groups, but the trabecular separation was higher and the number of trabecular bone was lower in the fracture group.

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Crowe, Nicole M. Crowe. „Histomorphometric Analysis of Elderly Ribs at Various Locations“. The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1503304250839703.

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Cole, Mary Elizabeth. „Optimizing Bone Loss Across the Lifespan: The Three-Dimensional Structure of Porosity in the Human Femoral Neck and Rib As a Metric of Bone Fragility“. The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1559033566505566.

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Pereira, Marcos Alexandre da Franca. „Descompressão dos segmentos timpânico e labiríntico do nervo facial via fossa craniana média“. Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5143/tde-02052016-090526/.

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Introdução: A paralisia facial periférica caracteriza-se pela interrupção, definitiva ou temporária, do funcionamento da musculatura facial. Decorre de lesão ou mau funcionamento das fibras do nervo facial. É uma enfermidade que causa enorme impacto estético e funcional. O topodiagnóstico e o tratamento da paralisia facial periférica pode requer abordagem médica e fonoaudiológica; ser exclusivamente medicamentoso ou associado à terapia de reabilitação, ou ainda, medicamentoso e cirúrgico, seguido da reabilitação da mímica facial. A via FCM tem sido usada para a descompressão do NF quando a audição precisa ser preservada. Esse acesso pode ser realizado de forma isolada, ou combinado à via transmastóidea. Objetivo: Descrever uma técnica inovadora para a descompressão do nervo facial via fossa craniana média que permite a exposição direta dos segmentos labiríntico e timpânico do nervo facial, com a preservação da função da orelha interna. Métodos: Vinte cabeças extraídas de cadáveres adultos de ambos os gêneros, sem sinais de malformação, traumatismo, doença ou manipulação cirúrgica prévia foram usados neste estudo. Os pontos de referência utilizados foram a artéria meníngea média, o nevo petroso superficial maior, a eminência arqueada, o seio petroso superior, e o plano meatal seguido no ápice petroso a partir da sua porção mais anterior e medial. Foi feita a dissecação do plano meatal, com visualização do meato acústico interno, seguido no ápice petroso a partir da sua porção mais anterior e medial até a região do gânglio geniculado. Foi aberto o tégmen timpânico e identificada a porção timpânica do nervo facial. A dissecação seguiu no sentido retrógrado da porção timpânica do nervo facial em direção ao gânglio geniculado, até a sua porção labiríntica. A aracnoide do meato acústico interno era aberta, e depois de identificado o nervo facial, a bainha deste nervo era aberta em extensão exposta. Resultados: As distâncias médias, entre o canal semicircular lateral e a porção média do cabo do martelo eram similares em ambos os lados (4,0mm±0,5mm). As distâncias médias, da porção timpânica do nervo facial até metade do cabo do martelo foram determinadas e resultaram em 2,0mm ± 0,44mm, e em 2,2mm ± 0,48mm para os lados direito e esquerdo, respectivamente. O segmento timpânico do nervo facial apresentou, em média, comprimento total de 11mm ± 0,67mm para o lado direito, e 11,5mm±0,60mm para o esquerdo. Os comprimentos longitudinais da janela óssea confeccionada no tégmen timpânico foram, em média, 16,8mm±1,67mm para o lado direito, e 16,8mm ± 1,20mm para o lado esquerdo. Já os comprimentos transversais da janela óssea confeccionada no tégmen timpânico foram, em média, 5,5mm ± 1,20mm e 5,0mm ± 1,75mm para os lados direito e esquerdo, respectivamente. O valor médio da área elíptica formada pelos comprimentos longitudinal e transversal da janela óssea confeccionada no tégmen timpânico foram 72,5mm2 ± 22,5mm2 à direita, e 65,9mm2 ± 30,3mm2 à esquerda. Conclusão: A técnica proposta pode ser utilizada para a cirurgia de descompressão do nervo facial via fossa craniana média, pois permite acesso aos segmentos timpânico, labiríntico e metal desse nervo, sem impor risco à audição. Pela possibilidade de acessar a porção timpânica do nervo, sem a necessidade da abertura da mastoide, o procedimento permite que se reduza o tempo cirúrgico e os riscos aos pacientes
Background: Peripheral facial palsy is characterized by the permanent or temporary interruption of the functioning of the facial muscles. The middle cranial fossa (MCF) approach has been used for the decompression of the facial nerve (FN) when hearing needs to be preserved. In this work, we describe an innovative technique for the decompression of the FN through the MCF approach that allows the direct exposure of the labyrinthine and entire tympanic segment of the FN, with the preservation of inner ear function. Methods: Twenty cadavers heads were used in this study. The reference landmarks used were the middle meningeal artery, the greater superficial petrosal nerve, the arcuate eminence, the inferior petrosal sinus and the meatal plane following the petrous apex from its most anterior and medial portion. Results: The tympanic segment of the FN presented, on average, a total length of 11 ± 0.67mm to the right, and 11.5 ± 0.60mm to the left. The longitudinal lengths of bone window in the tegmen tympani were 16.8±1.67mm to the right, and 16.8 ± 1.20mm to the left. The cross-sectional lengths of the bone window in the tegmen tympani were 5.5 ± 1.20mm and 5.0±1.75mm to the right and left sides, respectively. The average value of elliptical area formed by the longitudinal and transversal lengths of the bone window made in the tegmen tympani were 72.5 ± 22.5mm2 to the right, and 65.9 ± 30.3mm2 to the left. Conclusion: The proposed technique can be used for the surgical decompression of the tympanic, labyrinthine and meatal segments of the FN through the MCF, without imposing a risk to hearing, in addition to reducing the surgical time and the risk to patients

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Balabuszko, Rachel. „A Study of the Impact of a High Fat and High Cholesterol Diet on Cortical Bone in Captive Baboons“. The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1514721084433706.

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Pacheco, Andrielle de Bitencourt. „AVALIAÇÃO ANTROPOSCÓPICA E CEFALOMÉTRICA DO PERFIL E DA TENDÊNCIA FACIAL E SUA RELAÇÃO COM AS FUNÇÕES ESTOMATOGNÁTICAS“. Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/6547.

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Introduction: the profile and the facial tendency constitute the variation of bone and muscle structures of the individual, and may influence directly in the chewing, swallowing and breathing functions. Thus, the evaluation of these aspects is essential for Orofacial clinical work. The aim of this study was to investigate the correlation between the cephalometric and anthrophoscopic evaluation on the classification of profile and facial tendency, as well as to evaluate the association of these skeletal features with the functions of the stomatognathic system. Method: the sample consisted of 35 childrens, aged between six and twelve years, undergoing anthroposcopic evaluation with photographic documentation, with cephalometric and otorhinolaryngology evaluation. To verify the agreement between cephalometric and anthroposcopic evaluation was used the Kappa test. The association between profile and the facial tendency with the stomatognathic changes was analyzed using the Qui-square and Fisher Exact Test. Was adopted a significance level of p <0.05 for all tests. Results: the concordance among the judges in the classification of profile and the facial tendency was moderate. The concordance between the cephalometric and anthroposcopic evaluation as to profile was not possible as to analyze and the tendency was weak. Was observed good concordance between judges for the chewing variables and weak concordance for the swallowing variables. Was not found significant association between stomatognathic function and no association was found between stomatognathic functions with the facial profile and tendency. Conclusion: concludes that assessments and cephalometric antroposcópica differ and that changes stomatognathic not depend only on a few isolated variables.
Introdução: o perfil e a tendência facial constituem a variação de estruturas ósseas e musculares do indivíduo podendo influenciar diretamente nas funções de mastigação, deglutição e respiração. Por essa razão, a avaliação destes aspectos é essencial para a atuação clínica em motricidade orofacial. O objetivo deste estudo foi verificar a concordância entre a avaliação antroposcópica e cefalométrica quanto à classificação do perfil e da tendência facial, bem como, analisar a associação dessas características esqueléticas com as funções do sistema estomatognático. Metodologia: a amostra foi constituída por 35 crianças, com idades entre seis e doze anos, submetidas à avaliação antroposcópica com documentação fotográfica, avaliação cefalométrica e otorrinolaringológica. Para verificar a concordância entre as avaliações antroposcópica e cefalométrica utilizou-se o teste Kappa. A associação entre perfil e tendência facial com as alterações estomatognáticas foi analisada através dos testes Qui-Quadrado e Teste Exato de Fischer. Adotou-se nível de significância p<0,05 para todos os testes. Resultados: a concordância entre as juízas na classificação do perfil e da tendência facial foi moderada. A concordância entre as avaliações antroposcópica e cefalométrica quanto ao perfil não foi possível analisar e, quanto à tendência, foi fraca. Observou-se boa concordância entre juízas para as variáveis da mastigação e concordância fraca para as da deglutição e não foi encontrada associação entre funções estomatognáticas com o perfil e a tendência facial. Conclusão: conclui-se que as avaliações antroposcópica e cefalométrica diferem em relação ao perfil e à tendência facial e que as alterações estomatognáticas não dependem apenas das variáveis analisadas.

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Margolis, Julie Anna. „Tetracycline Labeled Bone Content Analysis of Ancient Nubian Remains from Kulubnarti“. The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429808453.

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Reiff, Rodrigo Bezerra de Menezes. „Reparo de defeito osteocondral no joelho de coelhos utilizando centrifugado de medula óssea autóloga“. Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/5/5140/tde-27092010-155257/.

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A cartilagem articular, por sua natureza avascular, apresenta uma capacidade limitada de regeneração. Uma abordagem terapêutica para o tratamento de defeitos da cartilagem consiste na utilização de células ou tecidos aplicados ao local da lesão. O objetivo deste estudo foi avaliar o efeito da aplicação de centrifugado de medula óssea autóloga em lesões osteocondrais no joelho de coelhos, em comparação com um grupo controle de lesões osteocondrais sem preenchimento, analisando o comportamento histológico destes grupos em função do tempo. Foram utilizados doze coelhos da raça Nova Zelândia, albinos, machos, adultos, submetidos a uma lesão osteocondral, de 4 mm de diâmetro e 3 mm de profundidade, em ambos os joelhos, na região da tróclea femoral. Nos joelhos direitos, que constituíram o Grupo Estudo, o defeito osteocondral foi preenchido por um coágulo de células mesenquimais, obtidas por centrifugação de um aspirado da medula óssea e selado com cola de fibrina. Nos joelhos esquerdos, que constituíram o Grupo Controle, o defeito osteocondral não recebeu qualquer preenchimento. Os animais foram divididos em três grupos de quatro coelhos, estudados após oito, 16 e 24 semanas. Os resultados foram descritos com base em uma escala de pontuação histológica que avaliou a morfologia celular, a reconstrução do osso subcondral, o aspecto da matriz, o preenchimento do defeito, a regularidade da superfície e a conexão das margens. A análise estatística foi realizada pelo Teste t-student para dados pareados na comparação entre Grupo Estudo e Grupo Controle. Para as comparações através do fator temporal, utilizou-se o Teste ANOVA one way. Com 5% de confiança, rejeitou-se a hipótese de igualdade entre os Grupos Estudo e Controle. Notou-se uma distância decrescente entre os escores dos Grupos Estudo e Controle com o aumento do tempo, bem como uma tendência crescente do valor da escala para o Grupo Controle. Concluiu-se que a aplicação de centrifugado de medula óssea em defeitos osteocondrais no joelho de coelhos mostrou melhor resultado na avaliação histológica, em comparação ao Grupo Controle. Analisando a evolução dos grupos através do tempo, houve uma aproximação de seus escores histológicos, sobretudo pelo aumento observado no Grupo Controle
The articular cartilage, due to its avascular nature, presents a limited regeneration capacity. A therapeutical approach to the treatment of cartilage defects consists of the utilization of cells or tissues applied to the lesion site. The aim of this study was to evaluate the effect of applying autologous bone marrow centrifuged in osteochondral lesions in the knees of rabbits, compared to a control group of osteochondral lesions without any filling, analyzing the behavior of these groups in terms of time. Twelve adult albino male New Zealand rabbits were used being submitted to an osteochondral lesion of 4 mm in diameter and 3 mm deep in both knees, at the femoral trochlea area. On the right knees, which comprised the Study Group, the osteochondral defect was filled by a clot of mesenchymal cells, obtained by centrifugation of an aspirate from bone marrow and sealed with fibrin glue. On the left knees, which comprised the Control Group, the osteochondral defect did not get any filling. The animals were divided into 3 groups of 4 rabbits, and studied after eight, 16 and 24 weeks. The results were described based on a histological grading scale which took into account the cell morphology, the subchondral bone reconstruction, the matrix staining, the filling of the defect, the surface regularity and the bonding of the edges. The statistical analysis was made by the t-student Test for paired data in the comparison between the Study Group and the Control Group. For the comparisons made by the time factor, it was used the ANOVA Test one way. With 5% level of confidence, the hypothesis of equality between the Study and Control Groups was rejected. It was observed a decreasing distance between scores of the Study and Control Groups as time increased, as well as an increasing tendency of the scale value for the Control Group. It was concluded that the application of autologous bone marrow centrifuged in osteochondral defects in the knees of rabbits showed better result in histological evaluation, in comparison to the Control Group. By analyzing the evolution of the groups through time, there was an approach of their histological scores, especially by the increase observed in the Control Group

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Patullo, Ive Maria Falcone. „Efeito da hipofunção mastigatória na massa óssea da mandíbula de ratas Wistar submetidas ou não a ovariectomia“. Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5166/tde-24092009-150336/.

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Objetivo: Examinar o efeito da hipofunção mastigatória e deficiência estrogênica no osso da mandíbula e comparar esta região com o osso da coluna e fêmur. Métodos: Vinte e quatro ratas Wistar foram ovariectomizadas (OVX) ou Sham-operadas (Sham) e analisadas após alimentação com dietanormal (Pellet) ou dieta-pó (Pó), divididas em 4 grupos: (GI) Sham-Pellet; (GII) OVX-Pelllet; (GIII) Sham-Pó; (GIV) OVX-Pó. A densidade mineral óssea (DMO) foi medida na coluna lombar e fêmur ao início e final do estudo, e a DMO (DMO inicial - DMO final) foi calculada. A DMO do osso mandibular e a histomorfometria foram analisadas ao final do experimento. Resultados: Os animais dos grupos Sham apresentaram DMO maior na coluna (GI:13.5% vs. GII:0.74%, p<0.01; GIII:10.67% vs. GIV:- 4.36%, p<0.001) e fêmur (GI:14.43% vs. GII:4.42%, p<0.01; GIII:10.58% vs. GIV:0.49%, p<0.001) que os dos grupos OVX, mas nenhuma diferença foi observada na DMO da mandíbula entre esses grupos (p>0,05). Por outro lado, os animais dos grupos de dieta-Pó mostraram diminuição da DMO da mandíbula quando comparados com os dos grupos de dieta-Pellet, (GIV vs. GII, p<0,01; GIII vs. GI, p<0,01). Semelhantemente, a análise histomorfométrica do côndilo mandibular mostrou que os grupos de dieta-Pó, apresentaram significante diminuição na espessura e volume trabecular quando comparado com os grupos de dieta-Pellet (GIV vs. GII, p<0,05; GIII vs. GI, p<0,01). Conclusão: Nossos resultados sugerem que a perda óssea mandibular foi resultado da diminuição da carga mecânica durante a mastigação, e a mandíbula não foi afetada pela supressão de estrogênio
Objectives: This study was designed to examine the effect of masticatory hypofunction and estrogen deficiency on mandible bone mass and compare this site with spine and femoral bone. Methods: Twenty-four rats were ovariectomized (OVX) or Sham-operated (Sham) and analyzed after feeding with hard-diet (Hard) or soft-diet (Soft). They were divided into 4 groups: (GI) Sham-Hard; (GII) OVX-Hard; (GIII) Sham-Soft and (GIV) OVX-Soft. Bone mineral density (BMD) was measured in the spine and femur in the baseline and at the end of the study, and BMD (final BMD baseline BMD) was calculated. In mandible bone, BMD and histomorphometry were analyzed at the end of the experiment. Results: Sham rats showed higher spine (GI: 13.5% vs. GII:0.74%, p<0.01; GIII:10.67% vs. GIV: - 4.36%, p<0.001) and femur BMD (GI:14.43% vs. GII:4.42%, p<0.01; GIII:10.58% vs. GIV:0.49%, p<0.001) than OVX but no difference was observed in mandible BMD among these groups (p>0.05). Soft-diet groups showed decreased mandible BMD compared with hard-diet groups (GIV vs. GII, p<0.01; GIII vs. GI, p<0.01). Similarly, mandibular condyle histomorphometry showed that soft-diet groups presented a significant decrease in trabecular thickness and volume (GIV vs. GII, p<0.05; GIII vs. GI, p<0.01) compared to hard-diet. Conclusions: Our results suggest that mandibular bone loss resulted from decreased mechanical loading during mastication, and was not affect by estrogen depletion

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Agnew, Amanda Marie. „Histomorphometry of the Elderly Rib: A methodological approach with implications for biomechanics, function, and fracture risk“. The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1305558389.

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Bittencourt, Aline Gomes. „Referências anatômicas ao giro basal da cóclea no assoalho da fossa craniana média para o implante coclear“. Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5143/tde-05082014-151655/.

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Introdução: A técnica clássica para o implante coclear é realizada por meio de mastoidectomia seguida de timpanotomia posterior. O acesso pela fossa craniana média provou ser uma alternativa valiosa, embora seja usada para o implante coclear, ainda sem normatização. Objetivo: Descrever um novo acesso pela fossa craniana média que expõe o giro basal da cóclea para o implante coclear. Métodos: Estudo anatômico de ossos temporais. Foram dissecados 50 ossos temporais. A cocleostomia foi realizada mediante um acesso via fossa craniana média, na porção mais superficial do giro basal da cóclea, usando o plano meatal e seio petroso superior como as principais referências anatômicas. Foi determinada a distância entre os pontos de referência, o ângulo entre o plano meatal e a cocleostomia, e a distância entre esta estrutura e a janela redonda. Foi realizada tomografia computadorizada em 5 dos ossos temporais utilizados neste estudo. Resultados: Em todos os 50 ossos temporais, apenas a porção mais superficial do giro basal da cóclea foi aberta e tanto as escalas timpânica como a vestibular foram visualizadas. As distâncias médias ± DP, menores e maiores, entre a cocleostomia e o plano meatal foram estimadas em 2,48±0,88mm e 3,11±0,86mm, respectivamente. A distância média da cocleostomia até a janela redonda foi de 8,38±1,96mm, e daquela até o seio petroso superior 9,19±1,59mm. As distâncias médias, menores e maiores, entre a cocleostomia e o eixo longo do plano meatal a partir da sua porção mais proximal foram estimadas em 6,63±1,38mm e 8,2±1,43mm, respectivamente. O valor médio do ângulo entre a cocleostomia e o plano meatal foi igual a 22,54±7,400. As tomografias computadorizadas demonstraram a inserção do feixe de eletrodos por meio do giro basal da cóclea até o seu ápice em todas as peças submetidas a este exame. Conclusão: A técnica proposta para identificar o giro basal da cóclea é simples e confiável. Igualmente, permite a visualização da escala timpânica e a inserção do feixe de eletrodos do implante coclear através desta câmara
Introduction: The classic technique for cochlear implantation uses mastoidectomy followed by posterior tympanotomy. The middle cranial fossa approach has proved to be a valuable alternative for cochlear implantation, although the standardization of this technique is still needed. Objectives: To describe a novel approach through the middle cranial fossa for exposing the cochlear basal turn for cochlear implantation. Materials And Methods: Anatomical temporal bone study. Fifty temporal bones were dissected. A cochleostomy was performed via a middle fossa approach on the most superficial part of the cochlear basal turn, using the meatal plane and superior petrous sinus as the main landmarks. The distance between the landmarks, the angle between the cochleostomy and the meatal plane, and the distance between this structure and the round window were measured. A computed tomography was performed on 5 of the studied temporal bones. Results: In all 50 temporal bones, only the superficial portion of the cochlear basal turn was uncovered. The cochlear exposure allowed both the scala tympani and vestibule to be exposed. The mean ± SD minor and major distances between the cochleostomy and the meatal plane were estimated to be 2.48±0.88mm and 3.11±0.86mm, respectively. The mean distance from the cochleostomy to the round window was 8.38±1.96mm, and that to the superior petrosal sinus was 9.19±1.59mm. The mean minor and major distances between the cochleostomy and the long axis of the meatal plane from its most proximal portion were estimated to be 6.63±1.38mm and 8.29±1.43mm, respectively. The mean angle between the cochleostomy and the meatal plane was 22.54±7.400. The computed tomography of all 5 temporal bones demonstrated the insertion of the implant array from the cochlear basal turn towards its apex. Conclusion: The proposed technique for identifying the cochlear basal turn is simple and trustworthy. Additionally, it enables visualization of the scala tympani, facilitating the insertion of the cochlear implant array through this chamber

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Schorr, Fabíola. „Colapsabilidade da faringe durante o sono induzido: comparação entre descendentes de Japoneses e indivíduos Brancos“. Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5150/tde-06082015-143937/.

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Introdução: A patogênese da apneia obstrutiva do sono (AOS) é complexa e pode variar de acordo com a etnia. O componente anatômico que predispõe à AOS é resultado da interação entre a estrutura óssea e partes moles da via aérea superior (VAS), e pode ser acessado através da pressão crítica de fechamento da faringe (Pcrit). Hipotetizamos que os descendentes de Japoneses e Caucasianos apresentam diferentes preditores para a colapsabilidade da VAS, sugerindo diferentes vias que levam ao desenvolvimento da AOS nestes dois grupos étnicos. Métodos: Homens descendentes de Japoneses (n=39) e Caucasianos (n=39), pareados para idade e gravidade da AOS, foram avaliados através de polissonografia (PSG), Pcrit e tomografia computadorizada (TC) da VAS e abdome para estudo da anatomia da via aérea e gordura abdominal, respectivamente. Resultados: Pcrit foi similar entre descendentes de Japoneses e Caucasianos (-1.0 ± 3.3 vs -0.4 ± 3.1 cmH20). Descendentes de Japoneses apresentaram menores dimensões ósseas craniofaciais (comprimento da base do crânio, maxila e mandíbula), enquanto que os Caucasianos apresentaram maior tamanho das partes moles da VAS (comprimento e volume da língua) e maior desbalanço entre o volume da língua e da mandíbula (razão entre o volume da língua e o volume da mandíbula). O ângulo da base do crânio apresentou associação com a Pcrit somente entre os descendentes de Japoneses (r=-0.535, p < 0.01). A razão volume da língua/volume mandibular se associou com a Pcrit somente nos Caucasianos (r=0.460, p < 0.01). Variáveis relacionadas à obesidade (IMC, circunferências cervical e abdominal, gordura visceral) mostraram correlação semelhante com a Pcrit em ambos os grupos. Conclusões: Descendentes de Japoneses e Caucasianos apresentam diferentes preditores da colapsabilidade da VAS. Enquanto a restrição óssea craniofacial foi determinante para a Pcrit somente entre os descendentes de Japoneses, o desbalanço anatômico entre o volume da língua e da mandíbula foi importante para a Pcrit nos Caucasianos. Estes achados podem ter implicações terapêuticas no tocante à melhora da predisposição anatômica para a AOS entre as etnias
Introduction: Obstructive sleep apnea (OSA) pathogenesis is complex and may vary according to ethnicity. The anatomical component predisposing to OSA is the result of the interaction between bony structure and upper airway soft tissues and can be assessed using passive critical closing pressure (Pcrit). We hypothesized that Japanese-Brazilians and Caucasians present different predictors to upper airway collapsibility, suggesting different causal pathways to develop OSA in these two groups. Methods: Male Japanese-Brazilians (n=39) and Caucasians (n=39) well matched for age and OSA severity were evaluated by full polysomnography, Pcrit and upper airway plus abdomen CT scans for determination of upper airway anatomy and abdominal fat, respectively. Results: Pcrit was similar between Japanese-Brazilians and Caucasians (-1.0 ± 3.3 vs -0.4 ± 3.1 cmH20). Japanese-Brazilians presented smaller upper airway bony dimensions (cranial base, maxillary and mandibular length) while Caucasians presented larger upper airway soft tissue (tongue length and volume) and greater imbalance between tongue and mandible (tongue/mandibular volume ratio). Cranial base angle was associated with Pcrit only among Japanese-Brazilians (r=-0.535, p < 0.01). Tongue/mandibular volume ratio was associated with Pcrit only among Caucasians (r=0.460, p < 0.01). Obesity-related variables (visceral fat, BMI, neck and waist circumferences) showed similar correlation with Pcrit in Japanese-Brazilians and Caucasians. Conclusions: Japanese-Brazilians and Caucasians present different predictors of upper airway collapsibility. While craniofacial bony restriction was determinant to Pcrit only in the Japanese-Brazilians, anatomical imbalance between tongue and mandible volume was important to Pcrit among Caucasians. These findings may have therapeutic implications regarding how to improve anatomical predisposition to OSA across ethnicities

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Lesser, Juan Carlos Cisneros. „Avaliação do trauma intracoclear causado pela inserção do feixe de eletrodos do implante coclear via fossa média em ossos temporais“. Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5143/tde-03052017-152606/.

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Introdução: O acesso pela via da fossa craniana média para colocação do implante coclear provou ser uma alternativa valiosa em pacientes com otite média crônica e cavidades de mastoidectomia instáveis, cócleas parcialmente ossificadas e em alguns casos de displasia do ouvido interno. Até hoje não existem pesquisas que descrevam se a inserção do feixe de eletrodos pela via da fossa média pode ser feita com um mínimo de traumatismo intracoclear, comparável ao observado nas inserções pela janela redonda. Objetivo: Avaliar o trauma intracoclear com dois modelos distintos de implante quando o feixe de eletrodos é inserido por cocleostomia na fossa craniana média em ossos temporais. Método: 20 ossos temporais retirados antes de 24 horas pós-óbito, foram implantados através do local da cocleostomia no giro basal da cóclea identificado no assoalho da fossa cerebral média. Dez peças receberam um implante reto e dez um pré-curvado, e foram fixadas em resina epóxi. Foi realizada tomografia computadorizada para determinar a colocação adequada do feixe eletrodos, profundidade de inserção e a distância entre a janela redonda e a cocleostomia. Por último, as peças foram polidas em série, tingidas e visualizadas por estereomicroscópio para avaliar a posição do feixe e trauma intracoclear. Resultados: A tomografia mostrou um posicionamento intracoclear do feixe de eletrodos nas 20 peças. No grupo dos implantes retos a média de eletrodos inserido foi 12,3 (10 a 14) e dos pré-curvados 15,1 (14 a 16) com uma diferença significativa (U=78, p=0,0001). A mediana de profundidade de inserção foi maior para o eletrodo pré-curvado (14,5mm) que para o reto (12,5mm) com diferenças estatisticamente significativas (U = 66, p = 0,021). Só uma das 20 inserções foi atraumática e 70% tiveram graus de trauma altos (grau 3 ou 4). Não foram observadas diferenças significativas do grau de trauma entre os dois tipos de feixes nem quando as inserções foram no sentido da janela redonda, comparado com o sentido do giro médio. Conclusões: A técnica cirúrgica utilizada permitiu a inserção do feixe de eletrodos na cóclea em todas as peças, porém sem garantir uma inserção na escala timpânica e com alto risco de trauma nas microestruturas da cóclea
Introduction: In recent years, a middle fossa approach has been described for the insertion of cochlear implants, and it proved to be a reliable alternative for implantation in patients with chronic supurative otitis media, unstable mastoid cavities with recurrent otorrhea, partially ossified cochlea and in some cases of inner ear dysplasia. Until now, no research has been done to describe if this approach allows for anatomic preservation and non-traumatic insertions comparable to those through the round window. Objective: To evaluate cochlear trauma when the cochlear implant electrode is inserted through a middle fossa approach by means of histologic and imaging studies in temporal bones. Methods: 20 temporal bones retrieved before 24 hours after death were implanted through a middle cranial fossa cochleostomy in the basal turn of the cochlea. Ten received a straight electrode and 10 a perimodiolar electrode. After reducing the bone size with preservation of the inner ear structures, the temporal bones were fixed, dehydrated and embedded in an epoxy resin. CT scans were performed to determine if an adequate direction of insertion was attained, the depth of insertion and the distance between the cochleostomy and the round window. At last, the samples were polished by micro-grinding technique and microscopically visualized to evaluate intracochlear trauma. Results: The CT-scan showed an adequate intracoclear position of the electrode in all the samples. In the straight electrode group the average number of inserted electrodes was 12.3 (10 to 14) against 15.1 (14- 16) for the perimodiolar (U=78, p=0.0001). The median depth of insertion was significantly larger for the perimodiolar electrode group (14.4mm vs. 12.5mm U=66, p = 0.021). Only one atraumatic insertion was achieved and 70% of the samples had important trauma (grades 3 and 4). No differences were identified for the trauma grades between the two groups of electrodes. Also, there were no differences in trauma if the cochlear implants were inserted in the direction of the basal turn of the cochlea or in the direction of the middle and apical turns. Conclusions: The surgical technique that was used allowed for a proper intracochlear insertion of the electrodes in all 20 temporal bones but it does not guarantee a correct scala tympani position and carries high trauma risk for the intracochlear microstructures

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Hanie, Elizabeth Anne. „Comparison of healing of full-thickness cartilage vs. full- thickness cartilage and subchondral bone defects in the equine third carpal bone“. Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040427/.

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Martins, Graziela de Souza Queiroz. „Avaliação do trauma intracoclear causado pela inserção do feixe de eletrodos do implante coclear via janela redonda em ossos temporais“. Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5143/tde-24062014-150219/.

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INTRODUÇÃO: A ampliação dos critérios de indicação para cirurgia do implante coclear e os benefícios da preservação da audição residual no pósoperatório estimularam o desenvolvimento de técnicas cirúrgicas atraumáticas. Minimizar os traumas intracocleares durante a inserção do feixe de eletrodos do implante coclear é um passo fundamental para este intuito. O objetivo deste trabalho é avaliar se o trauma intracoclear é diferente quando o feixe de eletrodos do implante coclear é inserido através do quadrante anterossuperior ou anteroinferior da membrana da janela redonda. MÉTODOS: Vinte e cinco ossos temporais frescos de cadáveres humanos foram submetidos à timpanomastoidectomia padrão. Após exposição adequada da membrana da janela redonda, em metade dos ossos o feixe de eletrodos do implante coclear foi inserido via quadrante anterossuperior da membrana da janela redonda, e na outra metade via quadrante anteroinferior. Os ossos temporais foram desidratados e embebidos em epóxi, com o feixe de eletrodos in situ. As peças foram serialmente polidas, tingidas e visualizadas por meio de estereomicroscópio para avaliar o trauma intracoclear causado pela inserção do feixe de eletrodos. As imagens foram fotografadas. RESULTADOS: Em treze ossos temporais o feixe de eletrodos do implante coclear foi inserido via quadrante anterossuperior da membrana da janela redonda, e em doze ossos via quadrante anteroinferior. Obteve-se 372 superfícies. As análises histológicas revelaram diferentes graus de traumas às estruturas intracocleares. Os resultados mostraram que a inserção do feixe de eletrodos via quadrante anterossuperior ou anteroinferior acarretam a mesma frequência de trauma intracoclear. CONCLUSÕES: A presença de trauma intracoclear e a severidade dos traumas ocorridos no tocante à inserção do feixe de eletrodos de implante coclear pelo quadrante anterossuperior e anteroinferior da membrana da janela redonda não apresentou diferença estatisticamente significativa. Observou-se, porém, maior facilidade para exposição cirúrgica do quadrante anterossuperior em relação ao quadrante anteroinferior
INTRODUCTION: The expansion of the indication criteria for cochlear implant surgery and the benefits of preserving residual hearing postoperatively have stimulated the development of atraumatic surgeries. Minimizing the intracochlear traumas during the electrodes insertion is a critical step for this aim. The objective of this study is to assess whether there is a difference in intracochlear trauma when the cochlear implant electrode array is inserted through the anterior-superior or anterior-inferior quadrants of the round window membrane. METHODS: Twenty-five fresh human temporal bones were submitted to standard tympanomastoidectomy. After adequate exposure of the round window membrane, in half of the bones the cochlear implant electrode array was inserted via anterior-superior quadrant of round window membrane and in the other half via anterior-inferior quadrant. The temporal bones were dehydrated and embedded in epoxy with the electrodes array in situ. The specimens were serially polished, stained and viewed through a stereomicroscope to assess the intracochlear trauma caused by insertion of the electrode array. Resulting images were documented. RESULTS: In thirteen temporal bones the cochlear implant electrode array was inserted via anterior-superior quadrant of round window membrane and in twelve bones via anterior-inferior quadrant. Three hundred and seventy two surfaces were obtained. Histological examinations revealed varying degrees of damage to the intracohlear structures. The results showed that the insertion of the electrode array via anterior-superior or anterior-inferior quadrant lead to the same frequency of intracochlear trauma. CONCLUSIONS: The presence of intracochlear trauma and severity of traumas regarding the insertion of cochlear implant electrode array via anterior-superior and via anterior-inferior quadrant of the round window membrane showed no statistically significant difference. However, it was observed that surgical exposure of anterior-superior quadrant was easier than surgical exposure of anterior-inferior quadrant

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Legendre, Lucas. „Les crocodiles sont-ils devenus secondairement ectothermes ? : étude paléohistologique“. Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066307/document.

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Les archosaures sont un clade de vertébrés comprenant les oiseaux, les crocodiliens, ainsi que de nombreux groupes fossiles. Ce groupe fait depuis plusieurs décennies l'objet d'un important débat parmi les paléontologues quant à l'évolution du thermométabolisme au sein de ses différentes lignées. L'hypothèse classique considère que seuls les oiseaux modernes sont endothermes, tandis que tous les autres archosaures sont ectothermes. L'histologie osseuse permet d'étudier plusieurs traits relatifs au thermométabolisme impossibles à mesurer sur des spécimens fossiles ; c'est pourquoi nous avons utilisé des caractères mesurés sur des coupes histologiques d'os longs.Nous nous sommes consacrés dans une première partie à une revue détaillée de la mesure du signal phylogénétique pour des caractères ostéohistologiques dans deux clades de vertébrés, ce qui nous a permis de mieux définir l'approche à suivre dans la construction de nos modèles prédictifs.Après une étude préliminaire consacrée à l'élaboration d'un modèle prédictif du taux de croissance osseuse, nous avons construit un modèle global capable de prédire directement le taux métabolique de nos spécimens fossiles. Nos résultats montrent que la majorité des archosaures de notre échantillonnage étaient endothermes. Cela implique que le dernier ancêtre commun des archosaures était probablement endotherme, et que les crocodiliens sont donc devenus secondairement ectothermes, probablement en réponse aux contraintes du milieu aquatique. Des études plus spécifiques sur la lignée des pseudosuchiens devraient permettre de déterminer à quel niveau de l'arbre phylogénétique s'est effectué le retour à cet état ectotherme
Archosaurs are a clade of vertebrates that includes birds, crocodiles, and numerous fossil groups. This clade has been a matter of debate among paleontologists for decades concerning the evolution of thermometabolism in its different lineages. The classical hypothesis considers that only modern birds are true endotherms, whereas all other archosaurs are ectotherms. Bone histology allows to study several traits linked to bone growth rate and thermometabolism, otherwise impossible to estimate on fossil specimens; for this reason, we used characters measured on long bone histological sections.In the first section, we extensively reviewed the measure of phylogenetic signal for osteohistological features in two clades of vertebrates, which was then used to define the methodology for building our predictive models.After a preliminary study during which we built a predictive model for bone growth rate, we built a global model to predict the metabolic rate of our fossil specimens, using both histological features and phylogenetic information for each specimen. Our results show that a majority of archosaurs in our sample were endotherms. This implies that the last common ancestor of archosaurs was likely an endotherm, and that modern crocodiles became secondarily ectothermic, probably in response to their aquatic environment. More specific studies on pseudosuchians should allow to precisely identify the level of the phylogenetic tree at which the ectothermic state was acquired, as well as adaptive constraints behind this acquisition

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Saxon, Leanne, und mikewood@deakin edu au. „The role of exercise in the development of bone strength during growth“. Deakin University. School of Health Sciences, 2002. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20051125.095337.

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Exercise during growth may increase peak bone mass; if the benefits are maintained it may reduce the risk of fracture later in life (1). It is hypothesised that exercise will preferentially enhance bone formation on the surface of cortical bone that is undergoing bone modeling at the time (2). Therefore, exercise may increase bone mass accrual on the outer periosteal surface during the pre- and peri-pubertal years, and on the inner endocortical surface during puberty (3). An increase in bone formation on the periosteal surface is, however, more effective for increasing bone strength than medullary contraction (4). While exercise may have a role in osteoporosis prevention, there is little evidential basis to support this notion. It is generally accepted that weight-bearing exercise is important, but it is not known how much, how often, what magnitude or how long children need to exercise before a clinically important increase in bone density is obtained. In this thesis, the effect of exercise on the growing skeleton is investigated in two projects. The first quantifies the magnitude and number of loads associated with and in a moderate and low impact exercise program and non-structured play. The second project examines how exercise affects bone size and shape during different stages of growth. Study One: The Assessment of the Magnitude of Exercise Loading and the Skeletal Response in Girls Questions: 1) Does moderate impact exercise lead to a greater increase in BMC than low impact exercise? 2) Does loading history influence the osteogenic response to moderate impact exercise? 3) What is the magnitude and number of loads that are associated with a moderate and low impact exercise program? Methods: Sixty-eight pre-and early-pubertal girls (aged 8.9±0.2 years) were randomised to either a moderate or low impact exercise regime for 8.5-months. In each exercise group the girls received either calcium fortified (-2000 mg/week) or non-fortified foods for the duration of the study. The magnitude and number of loads associated with the exercise programs and non-structured play were assessed using a Pedar in-sole mobile system and video footage, respectively. Findings: After adjusting for baseline BMC, change in length and calcium intake, the girls in the moderate exercise intervention showed greater increases in BMC at the tibia (2.7%) and total body (1.3%) (p ≤0.05). Girl's who participated in moderate impact sports outside of school, showed greater gains in BMC in response to the moderate impact exercise program compared to the low impact exercise program (2.5 to 4.5%, p ≤0.06 to 0.01). The moderate exercise program included -400 impacts per class, that were applied in a dynamic manner and the magnitude of impact was up to 4 times body weight. Conclusion: Moderate-impact exercise may be sufficient to enhance BMC accrual during the pre-pubertal years. However, loading history is likely to influence the osteogenic response to additional moderate impact exercise. These findings contribute towards the development of school-based exercise programs aimed at improving bone health of children. Study Two: Exercise Effect on Cortical Bone Morphology During Different Stages of Maturation in Tennis Players Questions: 1) How does exercise affect bone mass (BMC) bone geometry and bone strength during different stages of growth? 2) Is there an optimal stage during growth when exercise has the greatest affect on bone strength? Methods: MRI was used to measure average total bone, cortical and medullary areas at the mid- and distal-regions of the playing and non-playing humerii in 47 pre-, peri- and post-pubertal competitive female tennis players aged 8 to 17 years. To assess bone rigidity, each image was imported into Scion Image 4.0.2 and the maximum, minimum and polar second moments of area were calculated using a custom macro. DXA was used to measure BMC of the whole humerus. Longitudinal data was collected on 37 of the original cohort. Findings: Analysis of the entire cohort showed that exercise was associated with increased BMC and cortical area (8 to 14%), and bone rigidity (11 to 23%) (all p ≤0.05). The increase in cortical bone area was associated with periosteal expansion in the pre-pubertal years and endocortical contraction in the post-pubertal years (p ≤0.05). The exercise-related gains in bone mass that were accrued at the periosteum during the pre-pubertal years, did not increase with advanced maturation and/or additional training. Conclusion: Exercise increased cortical BMC by enhancing bone formation on the periosteal surface during the pre-pubertal years and on the endocortical surface in the post-pubertal years. However, bone strength only increased in response to bone acquisition on the periosteal surface. Therefore the pre-pubertal years appear to be the most opportune time for exercise to enhance BMC accrual and bone strength

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Nor, Faridah M. „A comparative microscopic study of human and non-human long bone histology“. Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4463.

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Identification of human or nonhuman skeletal remains is important in assisting the police and law enforcement officers for the investigation of forensic cases. Identification of bone can be difficult, especially in fragmented remains. It has been reported that 25 to 30% of medicolegal cases, which involved nonhuman skeletal remains have been mistaken for human. In such cases, histomorphometric method was used to identify human and nonhuman skeletal remains. However, literature has shown that histomorphometric data for human and nonhuman bone were insufficient. Additionally, age estimation in bone may help in the identification of human individual, which can be done by using a histomorphometric method. Age estimation is based on bone remodeling process, where microstructural parameters have strong correlations with age. Literature showed that age estimation has been done on the American and European populations. However, little work has been done in the Asian population. The aims of this project were thus, to identify human and nonhuman bone, and to estimate age in human bones by using histomorphometric analysis. In this project, 64 human bones and 65 animal bones were collected from the mortuary of the Universiti Kebangsaan Malaysia Medical Centre and the Zoos in Malaysia, respectively. A standard bone preparation was used to prepare human and nonhuman bone thin sections for histomorphometric assessment. Assessments were made on the microstructural parameters such as cortical thickness, medullary cavity diameter, osteon count, osteon diameter, osteon area, osteon perimeter, Haversian canal diameter, Haversian canal area, Haversian canal perimeter, and Haversian lamella count per osteon by using image analysis, and viewed under a transmitted light microscope. The microstructural measurements showed significant differences between human and nonhuman samples. The discriminant functions showed correct classification rates for 81.4% of cases, and the accuracy of identification was 96.9% for human and 66.2% for animal. Human age estimation showed a standard error of estimate of 10.41 years, comparable with those in the literature. This study project offers distinct advantages over currently available histomorphometric methods for human and nonhuman identification and human age estimation. This will have significant implications in the assessment of fragmentary skeletal and forensic population samples for identification purposes.

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Nor, Faridah Mohd. „A comparative microscopic study of human and non-human long bone histology“. Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4463.

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Identification of human or nonhuman skeletal remains is important in assisting the police and law enforcement officers for the investigation of forensic cases. Identification of bone can be difficult, especially in fragmented remains. It has been reported that 25 to 30% of medicolegal cases, which involved nonhuman skeletal remains have been mistaken for human. In such cases, histomorphometric method was used to identify human and nonhuman skeletal remains. However, literature has shown that histomorphometric data for human and nonhuman bone were insufficient. Additionally, age estimation in bone may help in the identification of human individual, which can be done by using a histomorphometric method. Age estimation is based on bone remodeling process, where microstructural parameters have strong correlations with age. Literature showed that age estimation has been done on the American and European populations. However, little work has been done in the Asian population. The aims of this project were thus, to identify human and nonhuman bone, and to estimate age in human bones by using histomorphometric analysis. In this project, 64 human bones and 65 animal bones were collected from the mortuary of the Universiti Kebangsaan Malaysia Medical Centre and the Zoos in Malaysia, respectively. A standard bone preparation was used to prepare human and nonhuman bone thin sections for histomorphometric assessment. Assessments were made on the microstructural parameters such as cortical thickness, medullary cavity diameter, osteon count, osteon diameter, osteon area, osteon perimeter, Haversian canal diameter, Haversian canal area, Haversian canal perimeter, and Haversian lamella count per osteon by using image analysis, and viewed under a transmitted light microscope. The microstructural measurements showed significant differences between human and nonhuman samples. The discriminant functions showed correct classification rates for 81.4% of cases, and the accuracy of identification was 96.9% for human and 66.2% for animal. Human age estimation showed a standard error of estimate of 10.41 years, comparable with those in the literature. This study project offers distinct advantages over currently available histomorphometric methods for human and nonhuman identification and human age estimation. This will have significant implications in the assessment of fragmentary skeletal and forensic population samples for identification purposes.

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Coraça, Debora Cristina. „Estudo experimental de implantes bioabsorviveis de poli(L-acido latico) / poli(oxido de etileno) associados ao cloridrato de vancomicina no reparo osseo“. [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313584.

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Orientador: Eliane Maria Ingrid Amstalden
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-06T03:49:09Z (GMT). No. of bitstreams: 1 Coraca_DeboraCristina_D.pdf: 21833278 bytes, checksum: d8fc3a57a4797f0daf7a2fca22979509 (MD5) Previous issue date: 2006
Resumo: A necessidade da utilização de enxertos naturais e/ou materiais sintéticos para auxiliar no reparo ósseo é diretamente proporcional a perda tecidual nas lesões. A administração de substâncias antibióticas é necessária para prevenir, ou mesmo combater a ação de agentes bacterianos que possam vir a retardar o reparo tecidual. Este estudo teve como objetivo avaliar a aplicação de um polímero bioabsorvível associado à uma droga antobiótica na regenereção óssea. Foram realizados implantes ósseos de microesferas da blenda de poli(L-ácido lático)PLLA/poli(óxido de etileno)PEO na composição 80:20 associadas ao cloridrato de vancomicina e não associados ao cloridrato de vancomicina em ratos. Os implantes foram colocados em cavidades de 3 mm de diâmetro realizadas em tíbias de ratos da linhagem Wistar. Grupos com 5 animais cada. foram submetidos a períodos experimentais de 2 e 4 dias e 1, 2, 4, 8, 16 e 32 semanas. Os achados morfológicos foram semelhantes em ambos grupos. Houve primeiramente a formação de malha de fibrina e hemorragia ao redor das microesferas, as quais foram gradualmente sendo substituídas por tecido de granulação. A partir do quarto dia, houve a formação inicial de matriz óssea envolvendo as microesferas centripetamente, tornando-se mais evidente e madura da primeira até a trigésima segunda semana de implantação. A comparação entre os achados histomorfométricos e semí-quantitativos, quanto à formação óssea, demonstraram não ter havido diferença significativa entre os dois grupos. Reações de rejeição tecidual não foram observadas. Pode-se concluir, portanto, que além da evidente osteointegração das microesferas de PLLA/PEO, a associação com o cloridrato de vancomicina não prejudicou a regeneração óssea podendo ser este material utilizado como enxerto, bem como ser útil na prevenção de infecções bacterianas
Abstract: The use of natural graft and synthetic materials to help bone regeneration is directly relative to cause of bone injury and bone requirement to compose a graft. The antibiotics drugs management is necessary to prevent and combat bacterial agents that could retard the tissue repair The aim of this study was to evaluate the bioabsorbable polymeric implants antibiotic associated behavior during the bone healing. Poly(L-lactic acid)PLLA/poly(ethylene oxide)PEO microspheres blends 80:20 vancomicyn associated bone implants, was compared with PLLA/PEO blend without vancomycin. The implants were inserted in a 3 mm proximal tibiae defect in adult Wistar rats. Periods from 2 and 4 days and 1. 2, 4, 8 16 and 32 weeks were evaluated in 5 animals per group. The histological findings were similar among groups. A fibrin net and hemorrhage were observed primarily around the microspheres and both were progressively replaced by granulation tissue. In four-day implant, the initial bone formation around microspheres was noted. The growth of bone tissue was initially characterized by wolven bone with progressive maturation to lamellar bone, centripetally to microspheres group. The quantity of new bone growth, measured by histomorphometric method and semi-quantitative analysis showed no differences between groups in each experimental interval. Therefore we conclude that mixing vancomycin chloridrate into PLLA/PEO microspheres did not affect the bone regeneration. Besides, the PLLA/PEO vancomycin associated microspheres allowed the osteointegration. For those reasons, the material could be used as bone graft, helping the bone repair In addiction, the associating with antibiotic drugs could be useful to prevent infections during bone healing
Doutorado
Ciencias Biomedicas
Doutor em Ciências Médicas

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Carvalho, Vanessa Graciela Gomes. „Ossos do sistema estomatognático e da articulação temporomandibular de cães e gatos: enfoque anátomo-cirúrgico“. Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-16062005-100126/.

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Sabe-se que o estudo da anatomia é de fundamental importância para todo e qualquer procedimento médico-cirúrgico, como também para o entendimento de toda a fisiologia e das doenças que acometem os seres vivos. Porém, para a prática da odontologia veterinária, especialidade que vem crescendo sobremaneira nos últimos anos, nota-se a ausência de uma compilação única do estudo anatômico da cabeça das espécies mais tratadas, especificamente cães e gatos. Considera-se, portanto, oportuno realizar um estudo geral dos ossos do crânio, dando ênfase ao sistema estomatognático e incluindo a articulação temporomandibular, visando descrever, ilustrar e correlacionar suas estruturas, aplicando este conhecimento na prática cirúrgica, ressaltando os pontos de maior importância para o desempenho da especialidade, disponibilizando uma base de conhecimento que atue como um \"guia" para o médico-veterinário que se interessa e pratica a odontologia veterinária. Para a realização das ilustrações, crânios de cães e gatos foram preparados pela técnica de maceração, fotografados e radiografados, com suas estruturas ósseas identificadas de acordo com as necessidades da correlação cirúrgica.
The study of anatomy is important to accomplish any kind of surgical and medical procedure and to understand the physiology and the diseases that happen in animals. Nowadays, veterinary dentistry is an important area of veterinary medicine which has been increasing and improving during the last years. However, currently, the veterinarian can not find any specific and exclusive literature about head anatomy of dogs and cats. It is therefore important to perform a study of the bones of the cranium, specially the bones of the stomatognathic system, including the temporomandibular joint, describing and illustrating the most important structures and correlating this knowledge with the surgical procedures. This paper serves the veterinarians that work with dentistry as a \"guide". The illustrations and the radiographs were made with macerated craniums of dogs and cats and had the structures identified according to the surgical necessities.

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Babinski, Monique da Silva Dias. „Análise morfométrica macroscópica e microscópica do fêmur da prole de ratas submetidas à desnutrição proteico-calórica no período de lactação“. Niterói, 2016. https://app.uff.br/riuff/handle/1/4701.

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Complexo Hospitalar de Niterói
O objetivo deste estudo foi avaliar os efeitos da restrição proteica e calórica materna durante a lactação, analisando se haveria recuperação, o conhecido “catch-up” das dimensões morfológicas femorais após a restauração da dieta nutricional. Ao nascimento da ninhada, as progenitoras foram divididas nos seguintes grupos: Controle (C) com dieta a 23% de proteína ad libitum; Restrição Proteico-Calórica (RPC) com dieta a 8% de proteína e Restrição Calórica (RC) com dieta a 23% de proteína, em quantidades restritas de acordo com a ingestão do grupo RPC. Após o desmame, todos os filhotes foram separados das mães e receberam livre acesso a uma dieta padrão de laboratório contendo 23% de proteína, até 180 dias, quando os ratos foram eutanasiados. O fêmur foi excisado e as dimensões femorais macroscópicas foram medidas usando pontos anatômicos pré-estabelecidos. Após a morfometria macroscópica, os fêmures foram fixados em formol 10% (24h) e descalcificados por EDTA. Foram realizadas secções transversais de 10μm de espessura no terço médio diafisário dos espécimes, corados com HE e levados ao microscópio para análise qualitativa e histomorfometria da cortical óssea. Os resultados morfométricos macroscópicos mostraram que a maioria das medidas nos grupos de RC e RPC foram significativamente menores do que no grupo controle. As maiores reduções ocorrendo no grupo de RPC e com várias anormalidades histoarquiteturais, eg., diminuição da área cortical e aumento da área medular. Cortical com lacunas aumentadas significativamente nos grupos RC e RPC. Nossos resultados mostram que a restrição proteico-calórica durante a lactação leva a uma recuperação incompleta na idade adulta. O fêmur mostrou redução significativa na maior parte dos parâmetros macro e microscópicos nos dois grupos tratados, em particular o grupo RPC, quando comparado com o grupo C
The aim of this study was to evaluate the effects of maternal protein and energy restriction during lactation, analyzing on morphological dimensions whether there was catch-up growth through normative nutrition restored, as well as on mechanical axis of femur of the offspring at adulthood. At parturition, Wistar rat dams were randomly assigned to the following groups: 1) control group (C) - free access to a standard laboratory diet containing 23 % protein, 2) protein-energy restricted group (PER) - free access to an isoenergetic, protein-restricted diet containing 8 % protein, and 3) energy-restricted group (ER) – fed with restricted amounts of a standard laboratory diet. At weaning, all pups were separated of dams and received free access to a standard laboratory diet containing 23% protein until 180 days, when the rats were anesthetized and sacrificed. The dimensions of excised pup femur were measured directly using pre-established anatomical points. After macroscopic morphometry, the femurs were fixed in 10% formalin (24h) and decalcified by EDTA. Cross sections of 10μm thickness were made in the middle third (diaphyseal) of the specimens stained with HE and taken to the microscope for qualitative analysis and histomorphometry of cortical bone. Morphometric analysis of the femur (macroscopic) showed that most of the measurements in the ER and PER groups were significantly lower than in the control group, with the greatest reductions occurring in the PER group and several histoarchitectural abnormalities, e.g., decrease in cortical area and increased medullary area. Cortical bone with gaps increased significantly in ER and PER groups. Our results show that protein and energy restriction during lactation leads to an incomplete catch-up growth in adulthood. The femur showed significant reduction in most of the parameters in the two treated groups, particularly the PER group, when compared to the control group

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Plasse, Martial. „Loi de Wolff et terrestrialisation : adaptation structure / fonction“. Thesis, Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=http://theses-intra.upmc.fr/modules/resources/download/theses/2019SORUS303.pdf.

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Le mode de vie des tétrapodes éteints est souvent difficile à évaluer sans adaptations morphologiques évidentes, comme des palettes natatoires. Selon l’hypothèse de l’adaptation fonctionnelle de l’os, l’architecture de l’os trabéculaire s’adapte avec précision aux chargements physiologiques. Les études précédentes ont déjà montré une relation claire entre l’architecture trabéculaire et le comportement locomoteur, principalement chez les mammifères et les oiseaux. Toutefois, le lien entre l’architecture trabéculaire et le mode de vie a rarement été étudié. Ici, l’architecture trabéculaire de différents reptiles a été mise en relation avec une large variabilité de modes de vie (aquatique, amphibie, terrestre). Les humeri de squamates, de tortues et crocodyliens ont été scannés par micro-tomographie à rayons X. L’analyse de volumes sphériques extraits de la métaphyse proximale de ces humeri a montré un signal phylogénétique significatif pour un seul des paramètres trabéculaires mesurés. Les analyses discriminantes linéaires suggèrent une bonne séparation des modes de vie selon les espaces morphologiques. De plus, une nouvelle méthode a permis d’estimer des chargements articulaires à partir de modèles d’éléments finis, issus de têtes humérales entières de tortues. Des biais liés aux fixations de ces modèles et à la forme de ces articulations ont été identifiés. Des chargements différents ont été calculés entre les nages et la marche de tortues amphibies. Enfin, les locomotions de deux tortues fossiles ont été inférées. Grâce à ces deux méthodes, l’architecture trabéculaire semble être un outil efficace pour inférer le mode de vie et la locomotion de tétrapodes éteints, spécialement ceux impliqués dans la terrestrialisation ou les retours au milieu aquatique
The lifestyle of extinct tetrapods is often difficult to assess when clear morphological adaptations, such as swimming paddles are absent. According to the hypothesis of bone functional adaptation, the architecture of trabecular bone adapts sensitively to physiological loadings. Previous studies have already shown a clear relation between trabecular architecture and locomotor behavior, mainly in mammals and birds. However, the link between trabecular architecture and lifestyle has rarely been examined. Here, trabecular architecture of different clades of reptiles has been correlated with a wide range of lifestyles (aquatic, amphibious, terrestrial). Humeri of squamates, turtles and crocodylians have been scanned with X-ray computed microtomography. The analysis of spherical volumes extracted from the proximal metaphyses of these humeri showed a significant phylogenetic signal for one of measured trabecular parameters. Linear discriminant analyses suggest a good separation of lifestyles in the morphological spaces. Furthermore, a new method allowed to estimate articular loadings for finite elements models from entire humeral heads of turtles. Biases related to fixations of these models and to their articular shapes has been identified. Different loadings has been calculated between the swimming and the walking of amphibious turtles. Finally, locomotions of two fossil turtles have been inferred. Thanks to these two methods, the trabecular architecture seems to be an effective tool to infer the lifestyle and the locomotion of extinct tetrapods, especially those involved in the terrestrialization and returns to aquatic environment

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Botha, Deona. „Histological age-at-death estimation in human bone: assessment of inter-population variation“. Thesis, 2019. https://hdl.handle.net/10539/29812.

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Original published work submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy, August 2019
Age-at-death estimates in skeletal remains are hampered by observer bias and error, as well as individual and population variation. This study aimed at improving accuracy and reliability of age estimates obtained from applying methods involving the assessment of histomorphometric variables of bone and bone mineral density (BMD). The assessment of osteon population density (OPD) and size (length, surface area and volume) of Haversian systems were investigated in three populations by means of stereology. Bone slides prepared from South African black (n = 99), South African white (n = 94) and Danish white (n = 30) individuals were analysed using MicroBrightField’s StereoInvestigator software. ANCOVA results revealed a statistically significant difference (p < 0.001) between the three groups in terms of OPD. No statistically significant difference was seen in the size of secondary osteons between the groups. Linear regression analysis was used to construct population-specific formulae for age-atdeath estimation in South African white and black individuals. The Danish sample was used as a comparative group for white South African standards established. Age mimicry appeared to play a role in the over-estimation of age in the Danish individuals, after which the problem was corrected by combining the two samples in order to achieve normal age distribution within the larger sample. Secondly, DXA scans of the proximal femur were done for a subgroup of South African black (n = 64) and white (n = 59) individuals for estimation of age-at-death from bone mineral density. Results displayed a significant difference between white and black groups for total and neck BMD. White males and females differed in total and neck BMD, although black males and females differed only in terms of neck BMD. Age could be significantly correlated with BMD in the white population, but not in the black population. Regression analysis was also done for the complete sample (white and black individuals pooled), as ancestry is unknown in some cases. A significant correlation was seen for age versus neck BMD in the total sample and in sex-specific groups. The outcome of this study suggested that the three population samples are somewhat dissimilar in bone microstructure, with differences related to OPD and BMD present between the groups. Based on this outcome, it should be emphasized that age estimation standards should be adapted to accommodate combined groups and create to more generally applicable standards. Further research involving various disciplines is needed to better understand the underlying reason(s) for these differences between these populations.
PH2020

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Wittwer-Backofen, U., J. Buckberry, A. Czarnetzki, S. Doppler, G. Grupe, G. Hotz, A. Kemkes et al. „Basics in paleodemography: a comparison of age indicators applied to the early medieval skeletal sample of Lauchheim“. 2008. http://hdl.handle.net/10454/6240.

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Recent advances in the methods of skeletal age estimation have rekindled interest in their applicability to paleodemography. The current study contributes to the discussion by applying several long established as well as recently developed or refined aging methods to a subsample of 121 adult skeletons from the early medieval cemetery of Lauchheim. The skeletal remains were analyzed by 13 independent observers using a variety of aging techniques (complex method and other multimethod approaches, Transition Analysis, cranial suture closure, auricular surface method, osteon density method, tooth root translucency measurement, and tooth cementum annulation counting). The age ranges and mean age estimations were compared and results indicate that all methods showed smaller age ranges for the younger individuals, but broader age ranges for the older age groups.

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Silveira, Geraldine Faccio da. „Considerações anatómicas sobre o envelhecimento do aparelho estomatognático“. Master's thesis, 2016. http://hdl.handle.net/10284/5590.

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Introdução: com o crescente aumento da expectativa de vida, o conhecimento das alterações anatómicas e fisiológicas que ocorrem no aparelho estomatognático durante o envelhecimento é de suma importância para a correta avaliação do paciente idoso. Objetivos: descrição e abordagem das principais estruturas anatómicas do indivíduo, adulto e idoso. Estabelece-se uma anatomia comparativa e evolutiva durante o processo de envelhecimento. Pretende-se contribuir para o conhecimento e reflexão sobre o tema em questão e demonstrar a aplicabilidade deste conhecimento em contexto clínico. Métodos: realizou-se pesquisa bibliográfica, nas bases de dados Pubmed, b-on SciElo e Elsevier, no período entre 2006-2016. Resultados: Maxila - ocorre reabsorção óssea, alteração no contorno do arco da maxila, retrusão maxilar, rotação da maxila no sentido horário, diminuição gradual e constante do ângulo maxilar e redução vertical da altura maxilar. Mandíbula - aumento do ângulo da mandíbula, diminuição da densidade e volume ósseo. Articulação gonfose e Articulação Temporo-Mandibular - pode ocorrer tanto anquilose, como perda das estruturas de suporte. Observa-se degeneração e/ou perfuração do disco radicular e alteração do formato do côndilo. Dentes - cáries radiculares, fraturas dentárias e desgaste dentário. Ocorrem modificações histológicas no esmalte, dentina e polpa dentária. Periodonto: reabsorção do osso alveolar, gengiva atrófica com tendência a migração apical, deposição apical das camadas incrementais e desgaste de cemento exposto, ligamento periodontal fino, irregular e diminuição do espaço periodontal. Conclusões: as alterações anatómicas decorrentes do envelhecimento fisiológico são múltiplas. O Médico Dentista diante de um paciente idoso, deverá conhecer e distinguir entre uma alteração decorrente do envelhecimento fisiológico e uma alteração patológica, para o correto diagnóstico clínico e uma excelente decisão terapêutica. O Médico Dentista deverá contribuir para o envelhecimento saudável e para tal deve ser conhecedor em pleno da temática do presente trabalho.
Introduction: Global average life expectancy is increasing. Understanding the normal age-related changes in the stomatognathic system is crucial practice in Geriatric Dentistry. Goals: description and approach of the main anatomical structures of the individual, adult and elderly. Establishing a comparative anatomy and evolving during the aging process. It is intended to contribute to knowledge and reflection on the topic in question and demonstrate the applicability of this knowledge in clinical context. Methods: Literature research in the Pubmed, b-on, SciElo and Elsevier. Inclusion of articles published between 2006-2016. Results: Maxillary - bone resorption, arch contour change, maxillary retraction, clockwise rotation, decrease angle and height reduction. Mandible - increase of angle and decreased of branch height, density and bone volume reduction. Gonfose joint and Temporomandibular joint - ankyloses or loss of support structures, degeneration and / or perforation of the disk and changes in the condyle format. Teeth - root caries, fractures and teeth wear. Histological changes in enamel, dentin and dental pulp. Periodontium - alveolar bone resorption, atrophic gum to apical migration, apical deposition of incremental layers and wear of exposed cementum, periodontal ligament thinning and periodontal space decrease. Conclusion: anatomical changes due to physiological aging are multiple. The dentist on an elderly patient should know and distinguish between a change resulting from normal aging and pathological change and an excellent therapeutic decision. The dentist should contribute to healthy aging and to do so must be knowledgeable in full the theme of this work.

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Villa, C., J. Buckberry, C. Cattaneo und N. Lynnerup. „Technical note: Reliability of Suchey-Brooks and Buckberry-Chamberlain methods on 3D visualizations from CT and laser scans“. 2013. http://hdl.handle.net/10454/6226.

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Previous studies have reported that the ageing method of Suchey-Brooks (pubic bone) and some of the features applied by Lovejoy et al. and Buckberry-Chamberlain (auricular surface) can be confidently performed on 3D visualizations from CT-scans. In this study, seven observers applied the Suchey-Brooks and the Buckberry-Chamberlain methods on 3D visualizations based on CT-scans and, for the first time, on 3D visualizations from laser scans. We examined how the bone features can be evaluated on 3D visualizations and whether the different modalities (direct observations of bones, 3D visualization from CT-scan and from laser scans) are alike to different observers. We found the best inter-observer agreement for the bones versus 3D visualizations, with the highest values for the auricular surface. Between the 3D modalities, less variability was obtained for the 3D laser visualizations. Fair inter-observer agreement was obtained in the evaluation of the pubic bone in all modalities. In 3D visualizations of the auricular surfaces, transverse organization and apical changes could be evaluated, although with high inter-observer variability; micro-, macroporosity and surface texture were very difficult to score. In conclusion, these methods were developed for dry bones, where they perform best. The Suchey-Brooks method can be applied on 3D visualizations from CT or laser, but with less accuracy than on dry bone. The Buckberry-Chamberlain method should be modified before application on 3D visualizations. Future investigation should focus on a different approach and different features: 3D laser scans could be analyzed with mathematical approaches and sub-surface features should be explored on CT-scans.

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McGurk, Ross J. „Variation of image counts with patient anatomy and development of a Monte Carlo simulation system for whole-body bone scans : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Medical Physics, University of Canterbury /“. 2007. http://hdl.handle.net/10092/1586.

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Wolf, Henrike. „Kann die pränatale Gabe von Dexamethason Einfluss auf die skelettale Entwicklung haben?“ Doctoral thesis, 2015. http://hdl.handle.net/11858/00-1735-0000-0023-997A-A.

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Die vorliegende Arbeit beschäftigt sich mit der Frage, inwieweit die pränatale Knochenentwicklung von der Dexamethasongabe beeinflusst wird. Die Glukokortikoidtherapie ist weit verbreitet und ihre Nebenwirkungen sind hinreichend bekannt. Auch die Wirkung auf den Knochenstoffwechsel wurde intensiv erforscht, allerdings nicht in Bezug auf die pränatale Therapie. Die Verabreichung von Dexamethason zur Vorbeugung des Atemnotsyndroms betrieb man zeitweise sehr intensiv. Mit Zunahme der Forschung auf diesem Gebiet, stellten sich allerdings erhebliche Auswirkungen auf die prä- und postnatale Entwicklung der Kinder heraus. Deswegen ist der Einsatz zur RDS-Prophylaxe heute relativ zurückhaltend. Zu diesem Zweck wurden 30 männliche Nachkommen der Spezies Callithrix jacchus, deren Mütter während der Schwangerschaft zu unterschiedlichen Zeitpunkten eine Dexamethasonapplikation erhielten, untersucht. Es erfolgte eine Einteilung in drei Gruppen: frühe Applikation, späte Applikation und in die Kontrollgruppe. Während der ersten beiden Lebensjahre wurden Körpergröße und Körpergewicht in regelmäßigen Abständen dokumentiert. Im Alter von 2 Jahren wurden die Tiere euthanasiert. Als Untersuchungsobjekte dienten Oberschenkel- und Schienbein-knochen. Es wurden die Kortikalisdicke, die Flächenverhältnisse von Trabekeln, rotem Knochenmark und gelben Fettmark analysiert sowie die Knochendichte ermittelt. Die Ergebnisse zeigen eine deutlich reduzierte diaphysale Kortikalisdicke beider Knochen in der Gruppe mit früher Dexamethasonapplikation. In der späten Appli-kationsgruppe dagegen fand man eine stärker ausgeprägte Kortikalis diaphysal, aber eine reduzierte im metaphysalen Bereich. Diese Schwächung kann besonders im Alter Frakturen im Oberschenkelhals begünstigen, vor allem wenn eine hormonell bedingte Osteoporose als Begleiterkrankung hinzukommt. In beiden Versuchsgruppen kann eine deutliche Schwächung der Knochensubstanz im Bereich der Knie, in diesem Fall die Hauptbelastungszone der Tiere, bedingt durch den Vierfüßlergang, nachgewiesen werden. Der Oberschenkel reagiert auf die Dexamethasonapplikation am sensitivsten. Des Weiteren sind Veränderungen der Flächenverhältnissen aufgetreten. Bei der frühen Applikation von Dexamethason ist eine deutlich reduzierte Anzahl an rotem Knochenmark zu finden, während bei der späten Applikation eine vermehrte Anzahl nachweisbar ist. Dies zeigt, dass Dexamethason auch Auswirkungen auf die Blutbildung und das Immunsystem mit sich bringt. Die Ergebnisse dieser Arbeit sollten dazu anregen, weiter auf diesem Gebiet zu forschen, da die Anzahl an Publikationen noch limitiert ist. Bezüglich der RDS-Prophylaxe ist über eine strengere Indikationsstellung nachzudenken.

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Curtis, Courtney Lee. „Wnt signaling in zebrafish fin regeneration : chemical biology using a GSK3β inhibitor“. Thesis, 2014. http://hdl.handle.net/1805/4835.

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Indiana University-Purdue University Indianapolis (IUPUI)
Bone growth can be impaired due to disease, such as osteoporosis. Currently, intermittent parathyroid hormone (PTH) treatment is the only approved therapy in the United States for anabolic bone growth in osteoporosis patients. The anabolic effects of PTH treatment are due, at least in part, to modulation of the Wnt/β-catenin pathway. Activation of the Wnt/ β-catenin pathway using a small molecule inhibitor of GSK3β was previously shown to increase markers of bone formation in vitro. Our study utilized a zebrafish model system to study Wnt activated fin regeneration and bone growth. Wnt signaling is the first genetically identified step in fin regeneration, and bony rays are the main structure in zebrafish fins. Thus, zebrafish fin regeneration may be a useful model to study Wnt signaling mediated bone growth. Fin regeneration experiments were conducted using various concentrations of a GSK3β inhibitor compound, LSN 2105786, for different treatment periods and regenerative outgrowth was measured at 4 and 7 days post amputation. Experiments revealed continuous low concentration (4-5 nM) treatment to be most effective at increasing regeneration. Higher concentrations inhibited fin growth, perhaps by excessive stimulation of differentiation programs. In situ hybridization experiments were performed to examine effects of GSK3β inhibitor on Wnt responsive gene expression. Experiments showed temporal and spatial changes on individual gene markers following GSK3β inhibitor treatment. Additionally, confocal microscopy and immunofluorescence labeling data indicated that the Wnt signaling intracellular signal transducer, β-catenin, accumulates throughout GSK3β inhibitor treated tissues. Finally, experiments revealed increased cell proliferation in fin regenerates following LSN 2105786 treatment. Together, these data indicate that bone growth in zebrafish fin regeneration is improved by activating Wnt signaling. Zebrafish Wnt signaling experiments provide a good model to study bone growth and bone repair mechanisms, and may provide an efficient drug discovery platform.

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Dissertationen zum Thema „Bone and Bones – anatomy – histology“

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