Dissertations / Theses: 'Tissue Bank'

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Lipworth, Wendy Louise. "Reconfiguring tissue banking consent through enrichment of a restricted debate." University of Sydney. History and Philosophy of Science, 2005. http://hdl.handle.net/2123/683.

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Tissue banks are thought to be an essential resource for medical research in the post-genomic age. Collections of tissue, usually removed in the course of diagnostic or therapeutic procedures, enable laboratory-based epidemiological studies to be carried out, linking abnormalities in the tissue to disease aetiology, prognosis and treatment responsiveness. There are, however, a number of technical, regulatory and ethical concerns that challenge those wishing to engage in tissue banking research. It is becoming increasingly apparent that tissue banking research is not without risk of harms, even though there is no direct physical risk to donors. This is because, in order to be most useful, banked specimens need to be linked to personal information about tissue donors and this poses the risk of inadvertent disclosure of personal─ particularly genetic─ information to those who might exploit such information (eg. insurance companies and employers). Furthermore, the long-term storage of specimens, and the impossibility of predicting all potential types of research programs for which they might be useful, raises the possibility that future projects will be carried out that are unacceptable to some (past) tissue donors. The ethical principles of autonomy and respect for persons demand that research subjects be informed of such risks and of the nature of the research, and that they participate willingly. On the other hand, there is a desire for science to progress unhindered by stringent consent requirements. For these reasons, a debate has emerged in the academic (bioethical and biomedical) literature and in the legal (law reform) sphere over what would constitute adequate consent. Despite an extensive discourse, it is still unclear whether it is permissible to carry out research on archival tissue that was originally taken for diagnostic purposes and whether project-specific (as opposed to open-ended) consent is required for research on tissue collected today. This lack of clarity is of concern to researchers, ethics committees and research subjects, all of whom recognise the importance of tissue banking research, yet fear that current consent procedures may be ethically or legally inadequate. Thus it is important that the consent dilemma be resolved as quickly and definitively as possible. Ongoing controversy and regulatory ambiguity are appropriate when morally contentious issues are at stake, and their existence does not, on its own, signal any flaws in the discourse process. There are, however, two reasons to suspect that the current �consent to tissue banking� debate, as portrayed in the academic literature and law reform documentation, is problematic. Firstly, the debate appears to be mired in an intractable conflict between those who want to maximise personal autonomy through stringent consent requirements, and those who want the scientific endeavour to progress in a manner that is unconstrained by what are viewed as arduous consent procedures. Secondly, the possible practical options (consent models) being generated by the debate are all limited because they are underpinned by a restricted notion of consent as an individualistic, legalistic and static activity, without consideration of any alternative conceptualisations of consent. Through a thematic analysis of the current �consent to tissue banking� debate in the academic and law reform literature (Section 3), this thesis shows that debate is essentially occurring between those who see individual autonomy (and stringent consent) as being of primary importance, and those who see unimpeded, market-driven scientific progress as the more important social good, which should not be impeded by unnecessarily stringent consent. Thematic analysis also confirms the existence of the two problems described above, and a failure of those engaged in the debate to reflect on, and challenge, the value-level assumptions underpinning their arguments and those of their opponents. It is argued that this lack of reflection accounts for the two problems: � Firstly, it precludes recognition of the cause of─ and, therefore, ways of resolving─ the intractable conflict at the centre of the debate. Value-level reflection shows that this is a result of the logical and moral conflict within western liberalism, between two modernist goods: individual freedom and scientific progress. � Secondly, it precludes the generation of varied conceptions of consent. Value-level reflection shows that the current range of consent models is restricted to procedures which are individualistic, abstract, static and legalistic, since they are underpinned by western liberal notions of autonomy and scientific progress. This recognition paves the way to consideration of alternative notions of autonomy, scientific progress and, therefore, consent, such as those derived from communitarian and feminist systems of values. A conceptually enriched model of tissue banking consent is then developed (Section 4). This model incorporates dominant (liberal) conceptions of autonomy and scientific progress as well as alternative notions of autonomy and scientific progress espoused by communitarian and feminist systems of values. It is argued that this conceptually-enriched model provides a practical solution to the two problems associated with the standard �consent to tissue banking� debate. In relation to the philosophically intractable conflict─ or what is termed the �modernist dilemma�─ between those privileging autonomy and those privileging scientific progress, it shows how the two apparently conflicting �modernist� goods can both be accommodated at a practical level, thus making the �consent to tissue banking� debate more tractable and fruitful. In relation to the restricted range of consent models being generated by the current debate, it provides new insights into the ways in which consent might be obtained such that a broader range of community values can be accommodated. More specifically, it stimulates the construction of a model that 1) involves communities, as opposed to merely individuals, in all stages of the scientific process; 2) is flexible and able to adapt consent procedures to specific contexts, rather than predefining procedures in abstract terms; and 3) is transactional and relational rather than static and legalistic. This outcome has interesting philosophical as well as practical implications. It shows that despite apparently unresolved, and possibly irresolvable, normative-level conflicts between the two modernist elements of western liberalism (autonomy and scientific progress), and between liberal, feminist and communitarian systems of values, a multi-perspectival, inclusive, model-building approach provides a practical solution that circumvents these normative-level conflicts.

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Murtomaa-Hautala, M. (Mari). "Species-specific effects of dioxin exposure on xenobiotic metabolism and hard tissue in voles." Doctoral thesis, Oulun yliopisto, 2012. http://urn.fi/urn:isbn:9789514297830.

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Abstract The evaluation of the effects and levels of contaminants in wildlife is an essential part of assessing risks for chemical exposure in the environment. Although the circumstances are not as controlled as in laboratory, wildlife studies offer the concept of environmental exposure in its entirety, with all the natural variation. In the present study, two wild vole species, bank vole (Myodes glareolus) and field vole (Microtus agrestis), were used in assessing environmental levels of dioxins. The effects of dioxin exposure on tooth and bone development were studied in order to determine whether they could be used as biomarkers for environmental exposure. Xenobiotic metabolism activity after dioxin exposure – both natural and experimental – was studied by quantifying selected cytochrome P-450 (CYP) enzymes. The results confirmed the fact that dioxins are ubiquitous in the environment, also in areas far from contaminant sources and human activity. The development of the third molar in bank vole was found to be a sensitive biomarker for dioxin exposure. The two vole species under study do not respond similarly to environmental concentrations of dioxins; there were significant differences in body burdens and activity levels of xenobiotic metabolizing enzymes
Tiivistelmä Haitallisten kemikaalien tason ja vaikutusten arviointi ympäristössä on olennainen osa kemikaalien riskin arviointia. Vaikka laboratoriossa olosuhteita kontrolloidaan ja tutkimukseen vaikuttava variaatio on paremmin hallittavissa, luonnonvaraisten lajien tutkiminen luo kokonaisvaltaisen ja todenmukaisen kuvan ympäristön kemikaalialtistuksesta kaikkine todellisine vaihteluineen. Tässä väitöskirjassa tarkastellaan kahden luonnonvaraisen pikkunisäkkään, metsämyyrän (Myodes glareolus) ja peltomyyrän (Microtus agrestis), käyttöä ympäristön kemikaalitason arvioinnissa. Pääpaino on dioksiinien kaltaisissa yhdisteissä. Työssä tutkitaan yhdisteiden kertymistä myyriin kahdessa ympäristössä: voimakkaasti dioksiineilla saastuneella maa-alueella sekä kaukana ihmistoiminnasta sijaitsevassa erämaassa. Herkiksi tiedettyjä vasteita – hampaiden ja luiden kehitystä – käytetään dioksiinialtistuksen indikaattoreina. Vierasainemetaboliasta vastaavien entsyymien (sytokromi P450 eli CYP) aktiivisuutta kartoitetaan molemmilla myyrälajeilla, jotta saadaan tietoa entsyymien indusoinnista luonnonvaraisilla myyrillä yleensä ja selvitetään havaittuja lajien välisiä eroja dioksiinivasteissa. Tulokset vahvistavat, että dioksiinit ovat laajalle levinneitä yhdisteitä, joita löytyy paitsi läheltä päästölähdettä myös kaukana ihmistoiminnasta olevilta alueilta. Metsämyyrällä kolmannen poskihampaan kehitys osoittautuu herkäksi dioksiinialtistuksen biomarkkeriksi. Samasta elinympäristöstä huolimatta tutkituista myyrälajeista mitatut dioksiinipitoisuudet eroavat huomattavasti toisistaan, samoin kuin vierasainemetaboliasta vastaavien entsyymien aktiivisuus ja niiden induktio TCDD-altistuksen jälkeen

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Triglia, Concetta. "Interpretive Phenomenological Analysis: Exploring the Experiences of Eye Bank Coordinators When Approaching Families of Decedents for Eye Donation." Diss., NSUWorks, 2018. https://nsuworks.nova.edu/hpd_hs_stuetd/9.

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This dissertation was used to addresses a group of individuals who work as eye bank coordinators. These individuals call families and approach them for eye donations from a loved one who has just passed away. An interpretative phenomenological analysis (IPA) was used to explain the lived experience of eye bank coordinators who call families for consent of eye tissue. The focus was to understand the dedication of the coordinators to giving the gift of sight and exploring the positive and negative experiences of eye bank coordinators. IPA is used for a keen understanding of eye bank coordinators, and the investigator gained insight as to why their role and well-being is important to eye banks by conducting and analyzing the interviews through the lived experiences of eye bank coordinators. The theoretical underpinnings of this research were based on the theory of planned behavior and self-perception theory. Four participants were interviewed as to their positive and negative experiences in their daily work. The research questions were What are the positive and negative experiences of eye bank coordinators when requesting permission for eye donations from bereaved families (RQ1)? and How do the positive and negative lived experience of eye bank coordinators influence their adjustment of strategies when requesting permission for eye donations from bereaved families (RQ2)? Encountering positive and enthusiastic family donors, needing to understand the situation or grief of family members, encountering closed-minded family members, and limited negative encounters experienced were the main themes that addressed RQ1. The main themes that addressed RQ2 were having the energy and motivation to seek for more donors, ensuring the right information was conveyed to the families, feeling more relaxed and comfortable, continuing to explain and ensure the correct information was conveyed, coaching and collecting oneself back, knowing how to read the actions and reactions of families, and learning from experiences and becoming more cautious.

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Santin, Stéfany Plumeri. "Avaliação morfológica e biomecânica dos efeitos da radiação gama em osso humano liofilizado ou congelado." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-04022014-153012/.

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Diversos pacientes são beneficiados com ossos armazenados em Bancos de Tecidos e utilizados em cirurgias reconstrutivas ortopédicas e em implantodologia como aloenxertos. No entanto, há uma intensa preocupação em garantir segurança na esterilidade do aloenxerto para proporcionar eficácia no transplante. Para minimizar possíveis contaminações utiliza-se a radiação ionizante como forma de esterilização final, desde que esta seja feita de maneira controlada, evitando possíveis modificações na matriz óssea. No presente trabalho, utilizamos as técnicas de colorimetria para avaliar modificações estéticas, Tomografia por Coerência Óptica, Tomografia por Coerência Óptica sensível à polarização, espectroscopia Raman e ensaios mecânicos de compressão para identificar as possíveis alterações na matriz óssea, ocasionadas pela forma de preservação, assim como, pelas diferentes doses de irradiação. Foram obtidas 8 amostras de fíbulas de 4 doadores, fracionadas de maneira a obter 48 amostras liofilizadas e 48 amostras congeladas. As amostras foram irradiadas com as doses de 15, 25 e 50 kGy comparando os resultados com o controle não irradiado. Observamos uma diminuição na intensidade das cores iniciais, mais relacionada com o processamento e preservação das amostras, e para as amostras irradiadas somente foi observado um aumento da coloração amarelada na dose de 50 kGy. A forma de preservação por liofilização ocasionou maiores modificações na estrutura terciária do colágeno dos ossos irradiados nas diferentes doses, principalmente nas doses acima de 25 kGy, porém estas modificações não foram suficientes para alterar a organização das fibras de colágeno. Quanto à resistência mecânica, verificou-se que as amostras liofilizadas foram menos resistentes que as congeladas e nas doses de 15 kGy e 25 kGy em ambas as formas de preservação ocorreu uma tendência a diminuir a resistência mecânica em relação ao controle.
Several patients are benefited with bones stored in Tissue Banks and used in orthopedic reconstructive surgery and implantodology as allografts. However, there is a strong concern to ensure safety in sterile allograft transplantation in order to provide efficacy. To minimize a probable contamination, ionizing radiation is used as a form of final sterilization, since the procedure is done in a controlled manner, avoiding possible changes in the bone matrix. In this dissertation, the techniques of colorimetry were used to evaluate aesthetic modifications; Optical Coherence Tomography, Optical Coherence Tomography sensitive to polarization, Raman spectroscopy and mechanical compression was carried out to identify possible changes in the bone matrix, caused by the preservation method, as well as the different irradiation doses. Eight fibulae from four donors were fractionated and from that forty-eight lyophilized samples and forty-eight frozen samples were obtained. The samples were irradiated with doses of 15, 25 and 50 kGy and the results were compared with the non-irradiated control. A decrease in the intensity of the initial colors was noticed and it was more related to the processing and preservation of the samples; for the irradiated samples, only an increase in the yellowness was observed, in the 50 kGy doses. The lyophilization preservation method caused major changes in the tertiary structure of the bone collagen irradiated at different doses, particularly at doses above 25 kGy, but these changes were not enough to change the organization of collagen fibers. Regarding the mechanical strength, were detected that lyophilized samples were less resistant than those which were frozen. With doses of 25 kGy and 15 kGy, in both forms of preservation, the mechanical strength tended to decrease, compared to the control. Therefore, it was observed that the aesthetic and structural changes caused by the different irradiation doses depend on the processing used in the Tissue Banks, besides the preservation method selected.

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Funari, Ana Paula. "Avaliação morfológica e biomecânica de tecido tendinoso humano esterilizado por radiação ionizante." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-23042018-093927/.

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O crescente aumento do interesse no desenvolvimento em técnicas cirúrgicas menos invasivas, como nas reconstruções tendíneas e ligamentares, tem levado ao aumento das pesquisas referentes ao uso de aloenxertos esterilizados por radiação ionizante. O processamento por radiação ionizante é um método seguro e não deixa resíduos, sendo utilizado como esterilização final. O presente estudo teve como proposta avaliar os efeitos da aplicação de radiação ionizante, produzida por fonte de 60Co, em amostras de tendões humanos pré processados de doadores multiorgãos obtidas por meio de colaboração com Bancos de Tecidos. O pré-processamento das amostras deu-se por métodos químicos e preservação por congelamento em -80 °C. As doses aplicadas no processamento por radiação foram de 12,5 kGy, 15,0 kGy e 25,0 kGy, cada uma com seu respectivo controle não irradiado. As amostras foram avaliadas por meio de testes histológicos, ópticos e biomecânicos, com o objetivo de analisar possíveis modificações morfológicas e estruturais. Os resultados apresentados demonstraram que o processamento por ultrassom e peróxido de hidrogênio causaram alterações na morfologia dos tecidos, o que ocasionou danos à sua estrutura, inviabilizando as amostras. Nas amostras processadas por álcool e antibiótico não foram observados danos na rede de colágeno pela aplicação da radiação. Os resultados dos testes biomecânicos apresentaram diferenças significativas entre os métodos aplicados. As amostras processadas com álcool e antibiótico apresentaram perda pouco significativa no módulo de elasticidade, comparadas às amostras processadas por ultrassom e peróxido de hidrogênio que mantiveram a propriedade viscoelástica. Contudo na dose de 12,5 kGy foi observado um aumento no módulo elástico e na viscoelasticidade. Com base nas análises, podemos concluir que o método de processamento com álcool, antibiótico e irradiação demonstrou menor dano, tanto na biomecânica quanto na esterilização, sendo que as amostras irradiadas a 15,0 e 25,0 kGy apresentaram características semelhantes ao controle não irradiado.
The increasing interest of development in less invasive surgical techniques, such as reconstructions of ligament tendon, has led to the increase of the research concerning the use of Allografts sterilized by ionizing radiation. Processing by ionizing radiation is a safe method and leaves no residues, being used as final sterilization. The present study was to evaluate the effects of proposed application of ionizing radiation, produced by 60Co source in human tendon pre-samples processed multiorgans donors obtained through collaboration with tissue banks. The pre-processing of samples given by chemical methods and preserved by freezing at -80 °C. The doses applied in radiation processing were 12.5, 15.0 and 25.0 kGy, each with your corresponding non-irradiated control. The samples were evaluated by means of histological and biomechanical testing, with the purpose of analyzing possible structural and morphological changes. The results showed that the ultrasound processing and hydrogen peroxide caused changes in the morphology of the tissues, which caused damage to the structure, making your samples. In the samples processed by alcohol and antibiotics were not observed damage on the network of collagen by the application of radiation. The results of biomechanical tests showed significant differences between the methods used. The samples processed with alcohol and antibiotics showed negligible loss in modulus of elasticity compared with the samples processed by ultrasound and hydrogen peroxide which kept the viscoelastic property, however in 12.5 kGy dose was observed an increase in elastic modulus and viscoelasticity. Based on the analysis we can conclude that the method of processing with alcohol, antibiotics and irradiation showed less damage, both in biomechanics and sterilization, in the samples irradiated with 15.0 and 25.0 kGy, showing results similar to the non-irradiated control.

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Lipworth, Wendy. "Reconfiguring tissue banking consent through enrichment of a restricted debate." Connect to full text, 2005. http://hdl.handle.net/2123/683.

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Thesis (M. Sc.)--University of Sydney, 2005.
Title from title screen (viewed 21 May 2008). Submitted in fulfilment of the requirements for the degree of Master of Science to the Unit for the History and Philosophy of Science and Centre for Values, Ethics and Law in Medicine. Includes bibliographical references. Also available in print form.

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Oliveira, Márcia Maria Benevenuto de. "A representação social de mulheres doadoras de leite humano." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/83/83131/tde-12052017-114529/.

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O leite humano pasteurizado vem sendo apresentado como a alternativa mais eficaz para alimentar prematuros e também recém-nascidos cujas mães estejam com alguma dificuldade para amamentar. Para suprir essa demanda, aumentou significativamente a implantação de bancos de leite humano no Brasil e no mundo. O objetivo desta pesquisa foi conhecer as representações sociais sobre a doação de leite entre mulheres colaboradoras do banco de leite humano em um hospital universitário público. Os referenciais teórico e metodológico utilizados foram, respectivamente, a Teoria das Representações Sociais e a Análise de Conteúdo. Para os dados quantitativos, foi utilizada a análise estatística descritiva. Foram entrevistadas 30 mulheres cadastradas como doadoras no Banco de Leite Humano do Hospital Universitário de Londrina, no Paraná. A idade variou de 18 a 44 anos, a maioria teve seus filhos por cesariana, 96,7% estavam com o companheiro, 86,7% possuíam curso superior completo ou pós-graduação, 76,7% exerciam trabalho remunerado fora de casa, o maior volume de leite doado foi 88 litros, o tempo médio de doação foi 155 dias e o tempo médio de aleitamento materno foi de 371 dias. Das falas dessas mulheres emergiram quatro temas com suas respectivas categorias: A experiência de amamentar; O banco de leite humano: lugar de acolhimento e aprendizagem; A doação dá trabalho e exige compromisso e Ser doadora é compartilhar o que tem e ajudar a quem precisa. A gênese para uma mulher se tornar doadora é estar amamentando seu filho e esse processo, proveniente da sua vivência familiar, apresenta-se como tendo um lado bom e outro que exige desafios, mas ela percebe que seu leite é único, que sua produção é mais do que suficiente para seu filho, levando essa mulher a procurar o banco de leite para compartilhar esse alimento com outras crianças. O banco de leite se torna para ela um local de acolhimento, apoio e aprendizado e ela se torna divulgadora desse serviço. Também passa a conhecer as histórias de doação e constata que doar seu leite dá trabalho, mas o compromisso assumido supera tal dificuldade; o apoio da família é essencial e ela descobre a sua maneira de ordenhar esse leite. Expressa que sente muito orgulho por ser uma doadora e, ao se perceber nessa condição, as suas representações sociais vinculam-se à construção social da solidariedade e de um sentimento mais profundo do significado da maternidade, que lhes propicia o sentimento de ampliar, para além de seu filho, o sentir ser mãe de muitos, em que compartilhar o que tem e ajudar a quem precisa resulta na sensação de ver mulptiplicado o papel materno e conhcer que doar vale a pena. Os elementos aqui identificados oferecem subsídios importantes para a condução de campanhas e projetos de melhoria de adesão de doadoras nos trabalhos dos Bancos de Leite Humano.
Pasteurized human milk has presented itself as the most effective alternative to feed preterm babies as well as newborns whose mothers are having some difficulty to breastfeed. In order to supply this demand, the number of human milk banks has significantly increased worldwide and in Brazil as well. The aim of this study was to acknowledge the social representation of human milk donation among women who donated to a human milk bank from a public hospital. The Social Representation Theory and Content Analysis were used as theoretical and methodological approaches, respectively. Quantitative data was assessed using descriptive statistical analysis. Thirty women were interviewed, all were donors at the Human Milk Bank from Londrina´s University Hospital, in Paraná State. Their age ranged from 18 to 44 years old, most had caesarean-sections, 96.7% had a companion; 86.7% had higher education or were postgraduates; 76.7% had a paid job; the biggest amount of donated milk was 88 liters; average donation period was 155 days; and average breastfeeding period was 371 days. Four themes and categories emerged from the women´s speeches: The breastfeeding experience; The human milk bank: a welcoming and learning place; Donating is hard-working and demands commitment; and Being a donor is sharing what I have and helping with others need. What motivates a woman to become a human milk donor involves the experience of breastfeeding her baby, which presents itself as a positive attitude, however posing some challenges. She realizes that her milk is unique, that she produces more than her baby can take, so she goes to the milk bank to share this nourishment with other children. The human milk bank becomes a welcoming, supportive and learning place for her, who spreads the word about this service/facility. These women also become aware of donation stories and comprehends that donating their milk is hardworking, but the commitment overcomes the difficulties; family support is essential; and they find out their own way to express the milk. These donating women reveal that they are proud to be a donor, and by acknowledging themselves as such, their social representations link to the social construction of solidarity and a deeper feeling of what maternity means. This allows them to amplify the motherhood feeling, beyond their own child, as they feel they are the mother of many. Also, sharing what they have and helping those in need results in the visualization of the multiplication of the mother´s role and understanding that donating milk is worthwhile. The elements identified in this study offer important ground to implement campaigns and projects to improve compliance in Human Milk Bank donations.

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Junior, Antonio Carlos Martinho. "Estudo dos efeitos da radiação ionizante em cartilagem costal humana por meio de Termogravimetria e Tomografia por Coerência Óptica." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-05112012-091524/.

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Bancos de Tecidos de diversas regiões do mundo têm estocado cartilagens humanas obtidas de doadores post mortem para uso em diversos tipos de cirurgias reconstrutivas. Para garantir que tais tecidos não estejam contaminados, estes têm sido esterilizados com radiação ionizante. Entretanto, altas doses de radiação gama podem causar efeitos indesejáveis nos tecidos. No presente trabalho, avaliamos a viabilidade de utilizar duas técnicas, Tomografia por Coerência Óptica (OCT) e Termogravimetria (TGA), para identificar possíveis modificações estruturais causadas na cartilagem costal humana em decorrência dos métodos de preservação e doses de radiação ionizante utilizadas. As cartilagens obtidas de doadores cadavéricos foram congeladas a -70 ºC ou preservadas em glicerol. A seguir, as amostras foram irradiadas por fontes de 60Co com doses de 15, 25 e 50 kGy. Nos resultados de TGA verificamos que as cartilagens preservadas em glicerol e irradiadas com diferentes doses de radiação não apresentaram diferenças estatisticamente significantes quando comparadas ao grupo controle, no que tange a taxa de desidratação do tecido, sendo que o mesmo não ocorre com cartilagens congeladas a -70 ºC e irradiadas com doses de 15 kGy. Em relação ao uso da técnica de OCT, por meio do cálculo do coeficiente de atenuação óptica total, verificamos que doses de 15 kGy promovem a criação de ligações cruzadas entre as fibrilas de colágeno, corroborando os resultados de TGA. Ainda, os valores do coeficiente de atenuação óptica total são diretamente proporcionais à tensão de ruptura das cartilagens, o que nos possibilitará, em um futuro próximo, predizer a qualidade de um enxerto sem a necessidade de perda de material biológico, visto ser o OCT um método não destrutivo. Por meio das imagens de PS-OCT podemos verificar que as doses de radiação utilizadas para esterilizar as amostras não provocam danos à rede de colágeno a ponto de que sua birrefringência seja perdida. Assim, o TGA e OCT são técnicas que podem ser utilizadas por bancos de tecidos de forma a verificar a qualidade dos tecidos antes de serem transplantados em pacientes.
Tissue Banks around the world have stored human cartilages obtained from post mortem donors for use in several kinds of reconstructive surgeries. To ensure that such tissues are not contaminated, they have been sterilized with ionizing radiation. However, high doses of gamma radiation may cause undesirable changes in the tissues. In this work, we evaluated the possibility of use Optical Coherence Tomography (OCT) and Thermogravimetric Analysis (TGA) to identify possible structural modifications caused by both preservation methods of cartilage and gamma irradiation doses. Cartilages were obtained from cadaveric donors and were frozen at -70 ºC or preserved in glycerol. Irradiation was performed by 60Co source with doses of 15, 25 and 50 kGy. Our TGA results showed that glycerolized cartilages irradiated with different doses of radiation does not presented statistical differences when compared to the control group for the dehydration rate. However, the same was not observed for deep-fronzen cartilages irradiated with 15 kGy. The results of OCT associated to total optical attenuation coefficient showed that doses of 15 kGy promote cross-link between collagen fibrils, corroborating the results obtained from TGA. Moreover, total optical attenuation coefficient values are proportionals to stress at break of cartilages, what will be very useful in a near future to predict the quality of the allografts, without unnecessary loss of biological tissue, once OCT is a nondestructive technique. By PS-OCT images, we found that high doses of ionizing radiation does not promote sufficient impairments to promote complete loss of tissue birefringence. Thus, TGA and OCT are techniques that can be used for tissue banks to verify tissue quality before its transplant.

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Almeida, Hirlana Gomes. "Transplante de córnea no Brasil: progresso e dificuldades em 16 anos." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5149/tde-28092018-104410/.

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Introdução: As doenças da córnea são responsáveis por cerca de 5% da cegueira reversível no mundo e o transplante de córnea (TC) é importante para o tratamento dessas enfermidades. A partir de fontes de dados oficiais e públicas, foram analisados o progresso e as dificuldades relacionados ao TC no Brasil nos últimos 16 anos, bem como desigualdades regionais, gastos do Sistema Único de Saúde (SUS) e indicadores de qualidade dos bancos de tecido ocular (BTOs). Métodos: Estudo retrospectivo e analítico com dados sobre TCs e BTOs no Brasil, no período de janeiro de 2001 a dezembro de 2016, divulgados pelo Sistema Nacional de Transplantes (SNT), pela Associação Brasileira de Transplante de Órgãos (ABTO) e pela Agência Nacional de Vigilância Sanitária (ANVISA). Para verificação de existência de tendência, comparação de médias entre as regiões e verificação da diferença de médias, foram utilizados o teste de Cochran-Armitage, a Análise de Variância e as comparações múltiplas de Duncan, respectivamente. Em todos os testes foi utilizado um nível de significância de 5%. Resultados: No Brasil, houve aumento: de 2,4 vezes no número de TCs (de 6.193 - 35,2 pmp para 14.641 - 71,0 pmp - p < 0,001); de 50,7% na eficácia do atendimento à demanda populacional por TCs (de 35,3% para 53,2% - p < 0,001); de 27,8% no número de globos e córneas in situ doados (de 24.608 - 127,1 pmp para 31.450 - 152,6 pmp - p < 0,001); de 31,7% nas córneas preservadas (de 21.012 para 27.674); de 2,4 vezes no gasto financeiro total com TCs (de R$ 9.179.688 para R$ 22.060.973); e de 2,2 vezes no gasto unitário com TC (de R$ 716 para R$ 1.603). A fila de espera para TC reduziu em 45,4% (de 23.549 - 123,0 pmp para 12.865 - 62,4 pmp - p < 0,001). As duas principais causas para a não doação foram as contraindicações médicas (média de 42,5%) e a recusa familiar (média de 36,6%). As principais causas de descarte de córneas foram a sorologia positiva para hepatite B (média de 33%), validade tecidual (média de 30,9%) e qualidade imprópria do tecido (16,8%). A Eficácia na Preservação de Córnea (EPC), o Coeficiente de Descarte de Córnea (CDC) e a Eficácia no Fornecimento de Córnea para Transplante (ECT) foram em média 88%, 37% e 63% ao longo dos anos, respectivamente. Os melhores índices foram apresentados nas regiões Sul, Centro-Oeste e Sudeste e os piores no Norte e Nordeste. Conclusão: No Brasil, o pequeno número de doações e a grande taxa de descarte de córneas são as principais dificuldades ao adequado atendimento à demanda populacional por TCs. Contudo, o país aumentou a capacidade de transplantar córneas e reduziu as filas de espera em 16 anos
Introduction: Corneal diseases account for about 5% of reversible blindness in the world and Corneal Transplantation (CT) is important for the treatment of these diseases. From official and public data sources, the progress and difficulties related to CT in Brazil in the last 16 years were analyzed, as well as regional inequalities, expenses for the Unified Health System (SUS) and quality indicators of ocular tissue banks (OTBs). Methods: A retrospective and analytical study with data on CT and OTB in Brazil, from January 2001 to December 2016, published by the National Transplantation System (SNT), the Brazilian Organ Transplantation Association (ABTO) and the National Surveillance Agency Sanitary (ANVISA). The Cochran-Armitage test, the Analysis of Variance and the Duncan\'s multiple comparisons were used to verify the existence of trend, comparison of means between regions and verification of the mean difference, respectively. A significance level of 5% was used in all tests. Results: In Brazil, there was an increase: of 2.4 times in the number of CTs (from 6,193 - 35.2 pmp to 14,641 - 71.0 pmp - p < 0.001); of 50.7% in the efficacy of meeting the population demand for CTs (from 35.3% to 53.2% - p < 0.001); of 27.8% in the number of donated globes and corneas in situ (from 24,608 - 127.1 pmp to 31,450 - 152.6 pmp - p < 0.001); of 31.7% in preserved corneas (from 21,012 to 27,674); of 2.4 times in the total finance expense with CTs (from R$ 9,179,688 to R$ 22,060,973); and 2.2 times the unit expense with CT (from R$ 716 to R$ 1,603). The waiting list for CT decreased by 45.4% (from 23,549 - 123.0 pmp to 12,865 - 62.4 pmp - p < 0.001). The two main causes for non-donation were medical contraindications (mean of 42.5%) and family refusal (mean of 36.6%). The main causes of corneal discard were positive serology for hepatitis B (mean of 33%), tissue validity (mean of 30.9%) and inadequate tissue quality (16.8%). Efficacy in Corneal Preservation (EPC), Corneal Discarding Coefficient (CDC) and Efficacy Supply of Corneas for Transplantation (ECT) averaged 88%, 37%, and 63% over the years, respectively. The best indexes were presented in the South, Midwest and Southeast regions and the worst in the North and Northeast. Conclusion: In Brazil, the small number of donations and the high rate of discard of corneas are the main difficulties to the adequate attendance to the population demand by CTs. However, the country increased the ability to transplant corneas and reduced waiting lists in 16 years

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Viana, Cristiano Ribeiro. "Avaliação do impacto da implantação do controle de qualidade em um banco de amostras teciduais criopreservadas." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-28052013-105525/.

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Bancos de tumores foram criados para organizar a coleta, arm azenamento e distribuição de amostras biológicas de pacientes oncológicos, favorecendo seu uso nas pesquis as sobre o cân cer. Amostras ade quadas devem ter RNA, DNA e proteínas de boa qualidade. RNA de boa qualidade deve estar íntegro e puro e DNA deve ter boa c oncentração e pur eza. Basea do em norm as in ternacionais, f oi elaborado e implantado um abrangente sistema de controle de qualidade no banco de tumores do Hospital de Câncer de Barretos, que para fins de estudo foi dividido em banco pré-controle de qu alidade (den ominado b anco pré) e em ban co pós- controle de qualidade (denominado banco pós). Objetivando comparar a qualidade das amostras n os dois bancos, atra vés d a extração d e R NA total e d e DNA (utilizando-se homogeneizador de tecidos e Kits), selecionou-se de forma aleatória 200 a mostras tumorais, distribuídas ig ualitariamente entre mama, co lorreto, estômago, pulmão e tireóide, sendo 100 do banco pré e 100 do banco pós. Para se avaliar a influência do tempo de isquemia fria (tempo entre a excisão do e spécime cirúrgico e o congelamento rápido da amostra armazenada) na qualidade do RNA total de amostras tumorais do banco pós, foram coletadas 200 amostras tumorais, distribuídas igualitariamente entre mama, co lorreto, estômago, pulmão e ti reóide, de 100 doadores diferentes, metade com o tempo de isquemia fria (TIF) de até 30 minutos e a o utra metade do mesmo espécime com TIF de 45 minutos. Extraiu-se RNA total dessas amostras (com maceração manual e Trizol) e comparou-se a sua qualidade, através do núm ero de i ntegridade do RNA (RIN), dentr o dos d ois intervalos de tempo e nas diferentes top ografias. Ao c omparar-se amostras com RIN acima de 7 (consideradas ideais para experimentos de microarray), do banco pré e do b anco pó s, for am enc ontrados 73 (73%) no p rimeiro e 87 (87%) no segundo (p=0,013). Ao comparar-se o intervalo de TIF de até 30 minutos com o de 45 minutos, encontrou-se respectivamente 63 (64,3%) e 3 6 (36%) amostras com RNA total intacto, 11 (11,2%) e 17 (17 %) com RNA tot al parcialmente degradado e 24 (24, 5%) e 47 (47%) com RNA t otal degradado (p<0,001). Amostras tireoidianas e colorretais f oram mais sensíveis ao a umento d o T IF (p=0,006 e p=0,03, respectivamente), e as de estômago e pulmão menos sensíveis (p=0,919 e p=0,384, resp ectivamente). Ao comparar-se a s 200 amostras dos dois ban cos, constatou-se que a grande maioria apresentava boa qualidade, porém o banco pós se destacou ao avaliar-se o número de amostras ideais para estudos de microarray, por provável interferência d o TIF, ainda não controlado no banco pr é. Constatou-se também que algumas amostras do banco pré, armazenadas há mais de ci nco anos em freezer a -80ºC, apresentaram excelente qualidade. O presente estudo também mostrou que o TIF é muito importante para a preservação da qualidade do RNA total, por isso, deve-se sempre respeitar o tempo máximo de 30 minutos. Ainda se observou que a de gradação do RNA é tecido dependente e qu e amostras processadas com homogeneizador de tecidos e extraídas com RNeas y Mini Kit apresentaram melhor q ualidade do RNA, qu e as macer adas manualmente e extraídas com Trizol
Tumor banks were created to or ganize the collection, storage and d istribution of biological samples of cancer pa tients, favoring it\'s use in cancer rese arches. Appropriate samples should have good quality of RNA, DNA and p roteins. RNA of good quality should be intact and pure and DNA should have good concentration and pu rity. Ba sed on international sta ndards, we elabo rated and imp lanted an comprehensive s ystem of qu ality control in the tu mor bank of Ba rretos Cancer Hospital, w hich was divided for st udy purposes i n pre bank quality control (denominated pre bank) and post bank qu ality control (denominated post bank). Aiming to compare the quality of the samples in two banks, through the extraction of total RNA and DNA (b y tissue homogenizer and Kits), we se lected 200 tumor samples in a random way, distributed equally among breast, colorectal, stomach, lung and thyroid, being 100 of the pre-bank and 100 of the post bank. To evaluate the influence o f cold ischem ia time (time b etween t he ex cision o f the su rgical specimen and the fast freezing of the stored sample) in the quality of total of RNA tumor sa mples of th e po st bank , we collected 2 00 t umor s amples, distrib uted equally among breast, colorectal, stom ach, lung and th yroid, fro m 100 different donors, half with the cold ischemia time (CIT) up to 30 minutes and the other ha lf of the sam e specimen with CIT exact ly 45 minutes. We ex tracted total RNA of these samples (with manual maceration and T rizol) and c ompared their qu ality, through the RNA integri ty number (RIN), ins ide tw o intervals of time a nd in different topographies. Comparing samples with RIN above 7 (considered ideals for microarray experiments), of the pre bank and of the post bank, we found 73 (73%) in the first and 87 (87%) in the second (p=0,013). Comparing the interval of CIT up to 30 m inutes with the ex actly 45 minutes, we found respectively 63 (64,3%) and 36 (36%) samples with total RNA intact, 11 (11,2%) and 17 (17%) with total RNA partially degraded and 24 (2 4,5%) and 47 (47%) wit h total RNA de graded (p<0,001). Thyroid and colorectal samples were more sensitive to the increase of CIT (p =0,006 and p=0,03, respectively), a nd s tomach and lun g samples less sensitive (p=0,919 and p=0,384, respectively). C omparing the 200 samples from the two b anks, we v erified that the great ma jority had good qu ality; however the post bank stood out the evaluating number of the id eal samples for m icroarray studies, for probable interference of CIT, still n o controlled in the pre bank. We also verified that some samples of the pre bank, stored more than 5 years in freezer at -80 ºC presented e xcellent qu ality. T he stu dy still sho wed that CIT is ver y important to preserve the quality of total RNA, for that, we sh ould always respect the maximum time of 30 minutes. We still observed that the degradation of RNA is tissue dependent and that samples processed with tissue homogenizer and extracted using RNeasy Mini Kit showed better quality of RNA that macerated manually and extracted with Trizol

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Antebi, Uri. "Efeitos da radiação ionizante nas proteínas presentes em ossos humanos desmineralizados, liofilizados ou congelados." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-06102015-102027/.

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Os tecidos ósseos alógenos são utilizados nas cirurgias de reconstrução ortopédicas e odontológicas. O número crescente de transplantes de ossos na última década beneficia diversos pacientes. Os profissionais dos Bancos de Tecidos utilizam protocolos que reduzem os riscos de transmissão de doenças infectocontagiosas, entretanto, não eliminam esta possibilidade. Portanto, é importante que tecidos sejam esterilizados por um método eficaz, sendo usualmente aplicada a radiação ionizante. Porém, a radiação ionizante pode acarretar alterações estruturais e biológicas nos ossos em relação à dose. O objetivo deste trabalho foi estudar os efeitos da aplicação da radiação gama e de feixe de elétrons, nas doses de 15 kGy, 25 kGy e 50 kGy nos tecidos ósseos desmineralizados preservados liofilizados ou congelados e avaliar as possíveis alterações no colágeno, na concentração de proteínas totais, BMP-2 e BMP-7. Para tanto foram utilizadas as técnicas de espectroscopia Raman, Bradford e ELISA. Foram utilizadas 5 diáfises de femur humano e parte das amostras foram desmineralizadas. As proteínas ósseas foram extraídas e quantificadas. Com os resultados da espectroscopia Raman, observamos que a eficiência da desmineralização foi de 85 a 90% porém com alterações na estrutura do colágeno. Alterações também foram observadas nos ossos congelados e irradiados nas doses de 25 kGy e 50 kGy. Nos resultados da quantificação de proteínas totais e específicas, ocorreram diminuições gradativas das concentrações médias das proteínas em relação à dose de radiação nos grupos estudados. Nas doses de radiação usualmente aplicadas aos tecidos ósseos, 15 kGy ou 25 kGy, as reduções nas concentrações das BMP-2 e BMP-7, foram menores que 20%. As reduções na dose de 50 kGy foram entre 27% a 53%, sendo influenciadas pelo tipo de radiação e pelo tipo de preservação dos ossos.
Allogenic bone tissues are used in orthopedic and dental reconstructive surgery. The growing number of bone transplants in the last decade benefits many patients. The professionals of Tissue Banks use protocols that reduce the risk of transmission of infectious diseases, however do not eliminate this possibility. Therefore, it is important that tissues are sterilized by an effective method, usually being applied ionizing radiation. However, ionizing radiation can cause structural and biological changes in the bones relative to the dose. The objective of this work was to study the effects of the application of gamma radiation and electron beam at doses of 15 kGy, 25 kGy and 50 kGy in the bone tissues demineralized preserved freeze-dried or frozen and to evaluate possible changes in collagen, the protein concentration total, BMP-2 and BMP-7. For both Raman spectroscopy techniques, Bradford and ELISA were used. They used 5 diaphyses human femur and part of the samples was demineralized. Bone proteins were extracted and quantified. With the results of Raman spectroscopy, we found that the efficiency of demineralization was 85-90% but with changes in the structure of collagen. Changes were also observed in frozen and irradiated bone at doses of 25 kGy and 50 kGy. The results of quantification of total and specific proteins, there were gradual decreases in average concentrations of proteins in relation to radiation dose in both groups. In the radiation doses usually applied to the bone tissue (15 kGy and 25 kGy) reductions in concentrations of BMP- 2 and BMP-7, were lower than 20%. The reductions at a dose of 50 kGy were between 27% to 53%, being influenced by the type of radiation and the kind of preservation of the bones.

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Tsoumpekos, Georgios. "big bang, a novel regulator of tissue growth in Drosophila melanogaster." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-201276.

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Multicellular organisms need to control their size throughout development and adult life in the face of challenges such as rapid growth. Unraveling the mechanisms that regulate tissue growth in epithelial tissues, in order to generate organs of correct size and proportion, remains a crucial goal of developmental biology. A suitable epithelial tissue for studying tissue growth in Drosophila, is the proliferative monolayer epithelial sheet of imaginal wing discs, which gives rise to the adult wing. The Hippo signaling pathway regulates tissue growth in wing development. There are several observations that link tissue growth/Hippo signaling with cell polarity and the actin cytoskeletal organization. The aim of this thesis was the study of the interplay between cell polarity, cytoskeletal organization and tissue growth. To gain further insight into how apical polarity proteins regulate tissue growth, an enhancer/suppressor screen that was previously conducted in our lab by Linda Nemetschke, was used. The screen was based on the modification of a dominant smaller wing phenotype induced upon overexpression of CrbextraTM-GFP. One of the enhancers identified in this screen is a gene called big bang (bbg). The absence of bbg results in smaller wings with a slower cell cycle and increased apoptosis in wing discs. bbg encodes a protein expressed in the apical cortex in wing disc cells and is required for the proper localization of apical proteins, like Crb, in wing disc epithelia. Bbg is also in the same complex with Spaghetti Squash (Sqh) in the apical cortex of the wing disc epithelia. sqh encodes an actin-binding protein that has actin cross-linking and contractile properties. Bbg stabilizes Sqh in the apical compartment of the cell. It is reported that both Crb and Sqh regulate tissue growth through the Hippo signaling pathway. In conclusion, Bbg regulates wing tissue growth, acting as a scaffolding molecule, through the proper localization of apical components of the cells like Crb and the cytoskeletal component Sqh.

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Gabrielsson, Gustav. "Tissue Compression Flossing - A systematic review." Thesis, Linnéuniversitetet, Institutionen för idrottsvetenskap (ID), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-104249.

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Background: Compression Tissue Flossing (CTF) is getting more and more popular. However, it is still unclear about the usability and function of CTF. Objective: The main objective was to investigate the current evidence on the function and usability of CTF by doing a systematic review. Methods: A PRISMA checklist was used to write this systematic review. Inclusion criteria; studies that examined CTF and its different effects published 2013-2021. The exclusion criteria were studies that were not published in English. The information sources used in this systematic review was done on PubMed and EBSCO (MEDLINE, CINAHL, SPORTDiscus) and as hand research. The methodological quality was assessed using the Physiotherapy Evidence Database scale and the AMSTAR. The method used to present the results is by organized tables where the study results are shown. Results: A total of 25 articles was included in the review. A total of 509 participants (mean age 22,6) was included. The average physiotherapy database score was 56% (range= 18,1%-81,8%). 15 studies were considered as high quality, 10 as low quality. Compression Tissue Flossing showed many different significant effects as increased range of motion, countermovement jump, rate of force development, increased torque, jump height, jump velocity, reduced muscle contraction time, and perception of flexibility. Conclusions: The results of this study suggest that compression tissue flossing has a good potential to be used in different contexts of sports performance/medicine. More studies are needed to validate the use of different floss bands and use them in bigger epidemiological settings as it right now seems to lack in its consistency depending on the pressure and application.

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Pruß, Axel. "Chemische und physikalische Verfahren zur Inaktivierung von pathogenen Mikroorganismen in allogenen Knochentransplantaten." Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2004. http://dx.doi.org/10.18452/13951.

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In allogeneic bone transplantation, the transmission of viral and non-viral infectious pathogens is the most severe undesirable concomitant phenomenon. The investigations published were examined regarding the inactivating capacity of inactivation procedures that are presently performed in bone banks (peracetic acid/ethanol, gamma irradiation, moist heat) against clinically relevant pathogens (aiming at a virus titer reduction of at least 4 log10 TCID50/ml or titer reduction of non-viral micro-organisms of at least 5 log10 cfu/ml). In the suspension experiments, treatment with peracetic acid/ethanol (peracetic acid 2%, ethanol 96%, aqua ad iniectabilia 2:1:1, 4 hours, 200 mbar, agitation) achieved a titer reduction of > 4 log10 already after 5 minutes for a number of viruses (PSR, PV, BVDV). HIV-2 was also inactivated within 5 minutes below the level of detection ( 4 log10 TCID50/ml was only reached after 4 hours. The results mentioned could be confirmed in the carrier test (contaminated spongiosa cuboids used as ‘worst case’ scenario). In the suspension experiment as well as in the carrier test, the HAV titer was reduced after 4 hours by only 3.7 log10 and 2.87 log10, respectively. The preceding step of defatting the spongiosa tissue by chloroform/ethanol was validated using cell-associated HAV and showed an HAV titer reduction of 7 log10. In the investigations regarding non-viral pathogens, all test organisms were completely inactivated by more than 5 log 10 steps (cfu/ml). Gamma irradiation was the second procedure examined. D10 values (irradiation dose required to reduce 90% of the pathogen titers by one log10 step) that were determined in inactivation kinetics experiments (irradiation conditions: –30°C, 60Co source) corresponded to data published so far. In order to provide for maximal safety, an irradiation dose of 34 kGy was recommended for allogeneic bone transplants using BPV and a diaphysis model from human femurs. The ‘Marburg bone bank system’ was the third procedure examined (thermal disinfection, guaranteed temperature of at least 82.5°C for a minimum of 15 min) using centrally contaminated human femoral heads. All viruses were completely inactivated and their titer reduced by more than 4 log10 steps. Vegetative bacteria and fungi were also completely inactivated (>= 6 log10 in the supernatant). As expected, spores and spore-forming pathogens were not sufficiently inactivated and not inactivated, respectively (titer reduction of less than 2 log10 cfu/ml). However, the latter group can be disregarded, since femoral heads are procured in the operation room under sterile conditions and the following production process rules out a secondary contamination with spores. It could be shown in the investigations presented that all three procedures examined guarantee an inactivation of the viruses investigated according to the recommendations by the senior federal authorities. The three treatment procedures offer additional biosafety by a comprehensive inactivation of non-viral pathogens.

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Wright, Jessica. "What influences the harmonisation of cancer tissue banks in the UK? : an ethnographic study." Thesis, University of Leicester, 2015. http://hdl.handle.net/2381/31806.

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Persuasive arguments exist as to why the harmonisation of tissue banks is important. Yet harmonisation has not happened on a large scale and empirical research has not investigated the reasons for this in detail. This thesis presents the results of ethnographic research using the case study of cancer tissue banks to identify influences on harmonisation. The research involved 40 interviews and over 117 hours of observations with professionals working across 15 organisations. Data analysis was based on the constant comparative method with use of sensitising constructs from literatures on standards and diffusion of innovation. A new model of the tissue supply chain was developed and refined against the findings. Harmonisation depends on the creation, implementation and outcome of standards. The empirical work showed that a complex picture of harmonisation emerges when the creation, implementation and outcome of standards are considered separately. Different factors act as barriers or facilitators, or as both, at each stage. Standard creation in cancer tissue banks is obstructed by a lack of agreement between organisations and professionals, who may have differing interests and views on the appropriate type and scope of standards, who should create them and how. Standard implementation can be enabled or hindered by standard design, the actions and features of organisations, and individual and professional factors. Critically, the outcome of implementing standards has not always increased harmonisation; in some cases the result is fragmentation, duplication or exclusion. The thesis describes cross-cutting political, social and technical issues that arise during the tissue supply chain and throughout the stages of standard creation and implementation, making harmonisation complicated and difficult to achieve. Eight recommendations are offered for how harmonisation can be facilitated in practice.

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Smith, Abraham Jeffrey. "Tissue Loss Syndromes in Acropora cervicornis off Broward County, Florida: Transmissibility, Rates of Skeletal Extension and Tissue Loss." NSUWorks, 2013. http://nsuworks.nova.edu/occ_stuetd/154.

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The high latitude thickets of Acropora cervicornis off Broward County flourish despite the presence of natural and anthropogenic impacts. These populations provided a unique study area in contrast to disease-stricken populations of the Florida Keys. This study used time-sequenced photographs to examine how A. cervicornis was affected by tissue loss attributed to white-band disease during 2007–2008. Variables monitored included healthy colony skeletal extension rates, diseased colony skeletal extension rates, and tissue loss. The transmissibility of the three white-band syndromes found in the Scooter and Oakland thickets was examined through tissue grafting experiments. Skeletal extension rates of healthy and diseased colonies were generally not significantly different. Mean skeletal extension for A. cervicornis colonies in Broward County was observed to be 9.6 cm/y (SD=3.95, Range: 1.02–19.9). Mean linear tissue loss from disease signs was 2.6 mm/d (SD=4.3, Range: 0.023–16.8). Although the majority of active disease lesions caused severe tissue loss upon contact with healthy branches, in 25% of the cases there was no tissue loss. Disease signs were also observed in 10% of the control grafting trials. A. cervicornis thickets in Broward County were growing at rates similar to those observed in this species elsewhere in Florida, but faster than other areas of the Western Atlantic. Tissue loss rate from disease lesions was lower than reported elsewhere. White-band disease and/or other tissue loss syndromes are always present in Broward County, but the low prevalence of affected colonies, inconsistent transmission of a presumptive agent that causes the disease signs, and optimum branch skeletal extension seems to limit effects on the thickets. Results of this research are significant as the current protected status of acroporid corals no longer allows manipulative research such as coral grafting for transmissibility of potential disease pathogens.

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Lutze, Ashleigh. "Back in the cycle: A review of the taphonomy of biomineralised tissues." Thesis, Lutze, Ashleigh (2022) Back in the cycle: A review of the taphonomy of biomineralised tissues. Masters by Coursework thesis, Murdoch University, 2022. https://researchrepository.murdoch.edu.au/id/eprint/65639/.

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After death, bones and teeth, biomineralized tissues composed of an organic and an inorganic part, are often the last remaining structures of an organism. The processes that affect biological tissues post-mortem is collectively defined as taphonomy. Forensic taphonomy studies the post-mortem modifications of remains in relation to a variety of physical, chemical, or biological agents, with the aim of assisting forensic investigations. Current research has typically focused on taphonomic effects observed in single depositional environments. This review summarizes the to-date information on the known taphonomic agents present across five depositional environments (burial, subaerial exposure, aquatic environments, burnt and frozen remains), and the effects generated on biomineralized tissues. Taphonomy is a relatively new sub-discipline of forensic anthropology and includes several areas where research is limited, such as the taphonomic processes in frozen and aquatic environments and the post-mortem alterations of teeth. As more research is conducted, the benefit of incorporating forensic taphonomy into forensic investigations have become increasingly evident. Each depositional environment features a range of characteristic taphonomic effects, which may be used to generate an accurate description of the post-mortem histories of remains. By providing training in forensic taphonomy investigative techniques, and incorporating them into investigations, more precise information may be gathered, potentially leading to faster turnaround times and case resolutions. The information presented in this review will prove useful in assisting the forensic community and may stimulate future research.

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Wiswedel, Klaus. "Sperm cryopreservation and artificial insemination at Groote Schuur Hospital." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/25895.

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The diagnosis and therapy managed by the specialities of infertile couples is traditionally of Gynaecology and Andrology. The latter is a subspeciality, which should combine the knowledge of urologists and gynaecologists in the treatment of sub or infertile men.

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Wan, Simon. "Self-assembling peptide hydrogel for intervertebral disc tissue engineering." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/selfassembling-peptide-hydrogel-for-intervertebral-disc-tissue-engineering(1f931e1e-6b9b-49a7-bd30-2572ff0338fa).html.

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The intervertebral disc (IVD), situated between adjoining vertebrae, consists of the gelatinous nucleus pulposus (NP) in the centre surrounded by the tougher annulus fibrosus (AF). Its main roles are to distribute loads and to act as joints. With aging, degenerative disc disease (DDD) occurs due to an imbalance in anabolic and catabolic events in the IVD, which results in a loss of function. Lower back pain (LBP) affects 84% of people at some point in their lifetime and is strongly associated with DDD. Current LBP treatments have limited long term efficacy and are symptomatic rather than curative. Cell-based therapies are regarded to hold great potential for the treatment of DDD as it has been hypothesised that they could regenerate the damaged tissue and alleviate LBP. A number of natural and synthetic biomaterials have been investigated as NP tissue engineering scaffolds with varying results. In this study, a self assembling peptide hydrogel (SAPH) was investigated for its potential as a cell carrier and/or scaffold for NP tissue engineering. SAPHs display the advantages of natural polymer hydrogels such as biocompatibility and biodegradability whilst combining the advantages of synthetic materials such as controlled structural and mechanical propertiesCharacterisation determined that the SAPH nanofibrous architecture had features that were of similar scale to extracellular matrix (ECM) components of the human NP. The mechanical properties of the SAPH could be optimised to closely match the native tissue. The system could shear thin and self-heal making the system ideally suited to delivery via minimally invasive procedure. The three dimensional (3D) culture of bovine NP cells (bNPCs) in the SAPH demonstrated that the NP phenotype could be restored after de-differentiation during monolayer culture. Gene expression results demonstrated that ‘traditional’ and ‘novel’ NP markers were highly expressed throughout in vitro culture. Cell viability was high, cell population remained stable and bNPCs adopted the characteristic rounded morphology of native NPCs. Finally, type II collagen and aggrecan, the main ECM components of the NP, were deposited with increasing production over culture period. Growth differentiation factor 6 (GDF-6) has been identified as the most promising current growth factor for inducing discogenic differentiation from human bone marrow mesenchymal stem cell (h-BMMSCs). After samples were stimulated with GDF-6, gene expression results confirmed that a NP-like phenotype could be induced with high expression of ‘traditional’ and ‘novel’ NP markers. Cell viability was high, cell population remained stable and NP associated ECM components were deposited with cells displaying a rounded morphology. Interestingly, when h-BMMSCs were cultured without GDF-6, it was strongly suggested that spontaneous discogenic differentiation occurred after culture in the SAPHs as ‘traditional’ and ‘novel’ NP markers were highly expressed, morphology was comparable to native NPCs and type II collagen and aggrecan were deposited extracellularly. If these findings were accurate then this is the first study to demonstrate that a NP-like phenotype could be induced from MSCs without use of an exogenous growth factor or a discogenic bioactive motif. Despite exciting and novel results, further work is required to confirm the potential of SAPHs for NP tissue engineering scaffolds.

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Tsoumpekos, Georgios [Verfasser], Elisabeth [Akademischer Betreuer] Knust, and Christian [Akademischer Betreuer] Dahmann. "big bang, a novel regulator of tissue growth in Drosophila melanogaster / Georgios Tsoumpekos. Betreuer: Elisabeth Knust. Gutachter: Christian Dahmann." Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://d-nb.info/1097048926/34.

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Benedict, Timothy Mark. "TISSUES AND TRAUMA: PAIN NEUROSCIENCE EDUCATION FOR VETERANS WITH POST-TRAUMATIC STRESS AND LOW BACK PAIN." UKnowledge, 2018. https://uknowledge.uky.edu/rehabsci_etds/51.

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Low back pain (LBP) is the top reason for Soldiers to seek medical care and one of the top reasons to be medically discharged. Mental health problems and psychosocial stressors have been increasing in Soldiers and are also top causes for medical discharge. Dysregulated stress has contributed to many Soldiers and Veterans to develop chronic LBP as well as mental health disorders like post-traumatic stress disorder (PTSD). Research suggests that psychosocial characteristics, as opposed to physical factors or tissue health, contribute to chronic pain the most. Focusing entirely on tissues for individuals seeking care for LBP can increase disability and vulnerability. Attributing physical pain to mental health concerns, however, risks stigmatizing patients or making them feel dismissed. The purpose of this dissertation was to develop a pain neuroscience education (PNE) program for Veterans and Soldiers with LBP and stress and determine if PNE is more effective in improving disability, PTSD symptoms, and beliefs about pain compared to traditional education about back pain and stress. This dissertation demonstrated that Veterans with PTSD can comprehend the neuroscience of pain and PTSD at a comparable level to a highly educated Veteran and medical panel without PTSD when adjusting for education. Since a proportion of participants were concerned that using military examples in PNE might increase PTSD symptoms, however, results from pilot testing suggested that the PNE materials developed for this dissertation should be tested in a clinical trial to ensure they do not increase PTSD symptoms. A systematic review and meta-analysis demonstrated that Veterans with PTSD have higher depression and pain-catastrophizing beliefs for a large effect size compared to Veterans without PTSD. Furthermore, Veterans with PTSD have significantly lower pain self-efficacy with a large effect size. Compared to Veterans without PTSD, Veterans with PTSD have higher pain and disability. These results, however, were not confirmed in Veterans presenting to a Physical Therapy clinic. In fact, this dissertation revealed that many of the negative outcomes previously attributed to PTSD in the literature may be due to the correlation between PTSD symptoms and pain-catastrophizing beliefs rather than from trauma. Furthermore, Veterans with chronic LBP do not appear to have different sensitivity levels to pressure based on PTSD symptoms. Finally, the results from a randomized controlled trial provide evidence that PNE greatly improves the confidence of Veterans and Soldiers to increase participation in social, work, and life roles despite the pain as measured by the pain self-efficacy questionnaire. Participants in the experimental group were more likely to achieve a meaningful reduction in disability at the 8-week follow-up compared to the control group. Furthermore, Veterans and Soldiers with LBP were more satisfied with how PNE explains pain and believed the PNE curriculum connected with their military experiences better than traditional psychosocial education about stress. Participants in the experimental arm were less likely to believe that exercise is harmful compared to traditional education. Finally, PNE improved PTSD symptoms beyond the clinically meaningful threshold in the experimental arm. In conclusion, PNE appears to be an effective treatment for PTSD, disability, and pain-related beliefs in Veterans and Soldiers with chronic LBP. These results should be replicated in a larger sample to ensure generalizability beyond the current study.

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Mirra, Inês Martins Pereira. "Influência das diferentes granulometrias na composição química das cascas de Eucalyptus globulus Labill., Betula pendula Roth, Picea abies (L.) Karst, Pinus sylvestris L. e Pinus pinea L." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4187.

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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
The goal of this report is to characterize the bark of five industrially important forest species in Europe - Eucalyptus globulus, Betula pendula, Picea abies, Pinus sylvestris e Pinus pinea and to define their potential use as a source of value added chemical products. It was performed the anatomical characterization of bark tissues (dissociated elements), the selective fractionation (size distribution, characterization of particle shape, separation of density and determination of bulk density), the average of basic chemical composition and particle size of three reference fractions (ash, extractives, suberin, Klason lignin, acid soluble lignin, holocellulose and 1% NaOH extraction). The anatomical study shows that there is no differential separation of the cellular elements of the tissues of the bark in seven particle size fractions. The physical process of fractioning showed that, for all barks, over 50% of the mass of material consisted of coarse particles with 6 mm average diameter. On the other hand, there was no direct correlation between the values of bulk density and particle diameter. It has only been possible to separate the birch bark and scots pine by difference in density fluctuations in water. The mean values of the chemical composition brought out that the barks of softwood showed higher content of total extractives, lignin and yield of 1% NaOH extraction. Considering the three different particle size fractions, the fine fraction showed a higher content of ash, total extractives and 1% NaOH extraction. There was no significant change in the content of suberin and holocellulose.

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Lakstins, Katherine S. "Investigating the human cartilage endplate in chronic low back pain: from mechanisms of degeneration to molecular, cell and tissue level characterization." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1584627459584403.

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Pompeu, Maria Helena. "Aspectos intervenientes na efetivação da doação do tecido ósseo durante o acolhimento e a entrevista familiar para doação de órgãos e tecidos." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/22/22131/tde-28012019-151736/.

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Atualmente existe uma lacuna de conhecimento referente à doação e ao transplante do tecido ósseo, já que muitas publicações concentram-se, principalmente, na temática \'doação e transplante de órgãos sólidos\'. O objetivo deste estudo foi compreender os aspectos intervenientes na efetivação da doação do tecido ósseo durante o acolhimento e a entrevista familiar, realizada pelos profissionais da Organização de Procura de Órgãos, na ótica do profissional e do familiar do potencial doador. Método: Este estudo de abordagem qualitativa, apoiado em conceitos do interacionismo simbólico, constituiu-se de familiares de doadores de órgãos e tecidos que autorizaram a doação do tecido ósseo no período de janeiro a dezembro de 2016, iniciando-se a partir de pesquisa nos prontuários da Organização de Procura de Órgãos localizada no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto/SP. Selecionaram-se todos os prontuários dos doadores de tecido ósseo, totalizando doze doadores Ainda, foram convidados a participar do estudo os quatro enfermeiros responsáveis pelo acolhimento e entrevista para solicitação dos órgãos e tecidos pertencentes à Organização de Procura dos Órgãos citada, por meio de uma entrevista gravada e realizada em seu contexto de trabalho. Foram entrevistados nove familiares e quatro enfermeiros mediante roteiro de entrevista contendo dados sociodemográficos e questões sobre a vivência de todo o processo de doação do tecido ósseo. O material foi transcrito e submetido a análise de conteúdo indutiva em três categorias temáticas: contexto onde se dá o processo de solicitação da doação, fatores que facilitaram a decisão pela doação do tecido ósseo e o resultado do processo de doação para o familiar. Observamos que os familiares, ao refletirem sobre o momento de decisão pela doação do tecido ósseo, revelaram que, apesar do desconhecimento desse tipo de doação, os aspectos que contribuíram para o consentimento foram a satisfação com o atendimento hospitalar humanizado, bem como o profissionalismo dos enfermeiros da Organização de Procura de Órgãos ao explicarem quais ossos seriam retirados e como seria reconstituído o corpo do doador; o conhecimento prévio da vontade do ente querido em ser um doador e o pensamento de estar \"fazendo o bem\". Observamos ainda que os enfermeiros, ao refletirem sobre seu papel na entrevista para solicitação da doação do tecido ósseo, revelaram que, inicialmente, o desconhecimento dos familiares quanto à possibilidade de doação do tecido ósseo, faz com que os mesmos reajam negativamente devido ao medo da deformidade do corpo. Objetivando superar esse momento difícil, os enfermeiros explicam todo o processo de captação do tecido ósseo, até a forma como seria entregue o corpo do familiar para o velório. Sugerem-se capacitações futuras à equipe de enfermeiros contribuindo para a otimização de todo o processo de doação do tecido ósseo para transplante. Acreditamos ser evidente a necessidade de educação voltada à população por meio de ações governamentais, em que futuras campanhas na divulgação da existência da doação do tecido ósseo possam promover um maior entendimento, resultando em uma reação menos traumática das pessoas no momento da solicitação do tecido ósseo
Currently there is a lack of knowledge regarding donation and transplantation of bone tissue, due many publications to focus primarily on donation and transplantation of solid organs. The aim of this study was to understand the intervening aspects on the effectiveness of bone tissue donation during approach and family interview, carried out by professionals of the Organ Procurement Organization, from perspective of professionals and potential donor relatives. Methods: It is a qualitative study, based on symbolic interactionism concepts; the sample was composed for relatives of donors of organs and tissues that authorized the donation of bone tissue in the period from January to December of 2016,.The first part was characterized for a data collection in the medical records from Organ Procurement Organization located in a Brazilian School Hospital. There were twelve donors during the selected period which medical records were selected to analyze. In addition, four nurses belonging to Organ Procurement Organization were invited to participate in study. They were responsible for the approach and interview with relatives to request organs. The data collection strategy was a structured interview which was recorded and performed in their workplace. Nine families and four nurses were interviewed using an interview script containing sociodemographic data and questions about the experience of entire process of donating bone tissue. The interviews were transcribed and submitted to analysis of inductive content in three thematic categories: the context where the donation request process happens, factors that facilitated the decision by the donation of the bone tissue and the donation process result to the relative. Results: It was observed that family members reflected on the moment of decision of bone tissue donation. They revealed that, despite the lack of knowledge about this type of donation, there were some aspects that contributed to the consent satisfaction with humanized hospital care as well as the nurses of the Organ Procurement Organization professionalism. These nurses explained which bones would be removed and how the donor\'s body would be reconstituted. Another contributed factor was the relatives prior knowledge of the being´s desire to be an organ donor and the \"doing good\" feeling. Meanwhile, the nurses interviewed revealed that initially there was family members\' lack of knowledge about the possibility of donation of the bone tissue, causes them to react negatively due to the fear of deformity of the body. The nurses explained the whole process of bone tissue withdrawal and the way which the deceased´s body would be delivered to the funeral. The aims of this approach were to overcome this difficult moment and family insecurity to make decision. Conclusions: Future nurses team training is suggested to improve all bone tissue donation for transplantation process. It is extremely important a population-oriented education through governmental actions, campaigns about bone tissue donation to promote a better understanding. It could result in less traumatic people reaction at the moment of bone tissue demand

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Barrezueta, Luis Fernando Mesias [UNIFESP]. "Imuno-expressão das proteínas da família BCL-2 (BCL-2. BCL-XL, BAX, BAK, BAD) em câncer gátrico, preparados em arranjo em matriz (TMA)." Universidade Federal de São Paulo (UNIFESP), 2009. http://repositorio.unifesp.br/handle/11600/9724.

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Made available in DSpace on 2015-07-22T20:50:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-01-28
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Em casos de carcinoma gástrico, para contribuir ao conhecimento do processo de carcinogênese: Objetivo: Estudar a expressão das proteínas da família Bcl-2 (BcI-2, Bcl-xl, Bak, Bad, Bax). Correlacionar a expressão destas proteínas com 0 índice apoptótico mediante a expressão da proteína Caspase 3 clivada, com 0 índice mit6tico mediante a expressão da proteína Ki-67 e com a expressão da proteína p53. Método: Técnica de arranjo em matriz de amostras teciduais (TMA): em 87 amostras de adenocarcinomas gástricos (grupo teste) e de mucosa gástrica não tumoral (grupo controle) foi avaliada a imuno-expressão das proteínas da família BcI-2 (BeI-2, Bcl-xl, Bak, Bad, Bax), da proteína p53, da proteína caspase 3 e da proteína Ki-67. Resultados: Todas as proteínas examinadas foram observadas nos adenocarcinomas e mucosa não tumoral, porem com diferenças de expressão em relação à porcentagem de positividade e intensidade. Observamos: i) Houve associação entre 0 tamanho do tumor e a proteína p53. ii) Houve associação da proteína Bad no adenocarcinoma com a idade dos pacientes. iii) Associação das proteínas Bax, Bad e Ki-67 com 0 adenocarcinoma de tipo intestinal. iv) As proteínas Bcl-xl, Bak, Bad, p53 e Ki-67 apresentaram diferenças estatisticamente significantes entre a imuno-expressão no tumor e na mucosa não tumoral. v) Associação das proteínas Bax, Bak e Bad na mucosa não tumoral. vi) Não houve correlação da imunoexpressão das proteínas com a sobrevida dos pacientes. Conclusão: A expressão aumentada da proteína Bcl-xl nos adenocarcinomas, com evidente diferença de expressão entre 0 grupo teste e 0 grupo controle, esta relacionada com 0 efeito anti-apoptótico da proteína. A expressão reduzida das proteínas Bak e Bad e a expressão aumentada das proteínas p53 e Ki-67 nos adenocarcinomas demonstram 0 desequilíbrio entre morte e proliferação celular, permitindo 0 crescimento descontrolado das células neoplásicas.
Purpose: To study the immunoexpression of Bcl-2 family proteins (Bcl-2, Bcl-xl, Bax, Bak, Bad) and to evaluate the correlation between the immunoexpression of these proteins with the cleaved caspases 3, Ki-67 and p53 immuno-expression. Methods: A TMA paraffin block was constructed with gastric carcinoma tissue (test group) and normal gastric adjoining mucosa (control group) of 87 patients. The TMA block was submitted to immunohistochemistry for Bcl-2, Bcl-xl, Bax, Bak, Bad, p53 and-cleaved Caspase 3. Results: All studied proteins were present in tumor and normal gastric adjoining mucosa, but with different intensity and amount of positive cells. i) There was an association between tumor size and p53 expression. ii) association between Bad expression in the tumor and patient’s age. iii) Intestinal type adenocarcinoma was positively correlated with the expression of Bax, Bad and Ki-67. iv) The protein Bcl-xl, Bak, Bad, p53 and Ki-67 showed statistically significant differences between the immuno-expression in tumor and normal gastric adjoining mucosa. v) There was an association between the proteins Bax, Bak and Bad expression in the normal gastric adjoining mucosa. vi) No correlation between patient’s survival rates and the expression of the proteins was observed. Conclusions: The higher expression of Bcl-xl protein in adenocarcinoma, the difference of Bcl-xl expression between test group and control group, might be related with the anti-apoptotic effect of this protein. The lower expression of Bak and Bad and the increased expression of p53 protein and Ki-67 protein in adenocarcinomas demonstrate the imbalance between death and cellular proliferation, which allows the uncontrolled tumor cell proliferation.
FAPESP: 04/09932-4
FAPESP: 06/54187-0
TEDE

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Goldsmith, Lee Huntington Trebbien. "Freezing tolerance and dehydrin protein expression in 'Frontenac' and 'Seyval blanc' grapevine bark and xylem cane tissues during acclimation, midwinter, and deacclimation." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1473210.

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Augustine, Robin. "Electromagnetic modelling of human tissues and its application on the interaction between antenna and human body in the BAN context." Phd thesis, Université Paris-Est, 2009. http://tel.archives-ouvertes.fr/tel-00499255.

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Les réseaux BAN (Body Area Network) révolutionnent le concept de la surveillance et de la prise en charge à distance de la santé du patient. Le BAN fournit des informations sur l'état de santé du patient en temps réel quelque soit l'endroit où il se trouve. Dans le « télé monitoring », des capteurs de mouvement, de respiration ou du rythme cardiaque placés à l'intérieur ou sur le corps humain transmettent des données via le réseau sans fil constituant le BAN, une antenne étant associée à chaque nœud du réseau. La communication peut être in/on, on/on ou on/off selon que les antennes sont placées à l'intérieur, sur ou à l'extérieur du corps. Le développement des BAN nécessite la réalisation de modèles (ou fantômes) simulant au mieux les propriétés électromagnétiques du corps humain. Des antennes portables, miniaturisées doivent être réalisées avec des contraintes d'intégration d'une part (aux vêtements, à des objets type montre ou badge), des contraintes de résistance ou de prise en compte de l'influence du corps d'autre part. La réduction de l'impact des antennes sur les tissus en terme de SAR (Specific Absorption Rate) doit également être considérée. Dans ce travail, l'objectif est de développer des fantômes valables pour les communications dans et sur le corps. Les matériaux de base sélectionnés sont d'origine biologique (biocéramiques et biopolymères) avec des propriétés proches de celles des tissus humains. Ces fantômes étant biocompatibles, ils sont essentiellement non toxiques alors que les fantômes usuels le sont en général. D'autre part, différents types d'antennes conformables, fonctionnant dans la bande ISM 2.4 GHz ont été développées et étudiées dans la perspective du BAN. Les antennes voient leur adaptation et leur efficacité chuter au contact ou à proximité du corps, ce qui constitue un écueil majeur pour établir une bonne communication. Différentes méthodes permettant de réduire l'influence du corps (plan de masse à l'arrière, surface haute impédance, feuille de ferrite polymère) sont testés et leurs avantages et inconvénients développés. Des mesures de SAR permettent aussi de démontrer l'efficacité de ces méthodes sur la réduction de la puissance absorbée par les tissus. Au final, ce travail apporte une contribution à l'étude théorique et expérimentale de l'interaction entre corps humain et antenne dans le cadre des réseaux BAN appliqués à la télésurveillance de la santé

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Di, Lauro Steven. "Time-Series Evaluation of Suspect Rickettsiales-like Bacteria Presence in Acropora cervicornis off of Broward County from Years 2001–2012." NSUWorks, 2015. http://nsuworks.nova.edu/occ_stuetd/379.

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Rickettsiales-like organisms (RLOs) are thought to be related to bacteria in the order Rickettsiales. They have been reported to occur in the staghorn coral (Acropora cervicornis), and this study investigated trends of infection over time, and in relation to the health of infected corals. This study focuses on tissue samples taken mostly from visibly healthy A. cervicornis thickets in Broward County, Florida, and processed for histological examination. Samples were originally collected and analyzed to document reproduction during years 2001 through 2012, and tissue loss diseases (white-band disease [WBD] types I and II, and rapid tissue loss). The presence of suspect RLOs, the presence of ovoid bacterial aggregates in the basal body wall, and the condition of the coral tissue were examined in hematoxylin and eosin (H&E) and Giemsa-stained sections. Determination was made as to whether suspect RLO infection severity, location, or the presence of bacterial aggregates are correlated with changes in tissue condition associated with WBD. To better understand progression, trends, and periodicity in bacterial presence and coral tissue health, these data were then further analyzed for potential correlation with the month, year, and average monthly nighttime sea surface temperatures (categorized into ranges above, within, or below 24–29°C) when samples were collected. The severity of suspect RLO infections and the presence of bacterial aggregates in A. cervicornis varied over time, with no correlation with the location of suspect RLOs within the polyp. High suspect RLO prevalence was correlated with normal tissue conditions, while low suspect RLO prevalence was correlated with abnormal tissue conditions. However, high prevalence of bacterial aggregates was correlated to abnormal tissue conditions. Epidermal RLO and overall suspect RLO prevalence severity scores were significantly higher among samples collected when monthly average nighttime sea surface temperatures were below 24°C in contrast to samples collected when temperatures were between 24–29°C, suggesting direct or indirect effects of sea surface temperatures on infection severity. The areas of suspect RLO intracellular bodies within infected mucocytes were measured using digital image analysis software and found to be positively correlated with worsening coral tissue condition. Semiquantitative variable scores for histoslides stained with H&E were significantly different from those stained with Giemsa, indicating that these stains cannot be used interchangeably to study the presence of bacteria and the condition of coral tissue. Overall, the results of this study indicate that infection severity of suspect RLOs and the presence of bacterial aggregates are variable and correlated with the incidence of WBD-I in A. cervicornis. However, the exact nature of this relationship remains unclear. Further studies are necessary to interpret trends detected during this analysis to develop a better understanding of what contributes to the severe tissue-loss outbreaks and mortalities of A. cervicornis.

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Croft, Emily C. "Alterations in Active and Passive Behavior of Lower Back Tissues Following Six Sessions of High Velocity Low Amplitude Spinal Manipulative Therapy for Healthy Participants." UKnowledge, 2016. http://uknowledge.uky.edu/cbme_etds/37.

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Non-specific low back pain (LBP) is a major health problem affecting a substantial portion of the population. The current treatments offered for non-specific LBP are oftentimes unsuccessful because the acting mechanism(s) of most treatment options are unknown. Obtaining a better understanding about the acting mechanism behind existing treatment options is, therefore, essential for the improvement of non-specific LBP treatment and management. The objective of this study was to gain a more comprehensive understanding about the acting mechanism of high velocity low amplitude spinal manipulative therapy, specifically the impact that high velocity low amplitude spinal manipulative therapy may have on the active and passive spinal musculoskeletal stabilizing subsystems along with the resultant spinal stability for healthy participants. A pre-post intervention study design completed by six healthy participants was used to quantify changes in the above noted aspects of spinal stability using a series of tests performed both before and after six sessions of high velocity low amplitude spinal manipulative therapy. The tests included seated balancing tests, lower back range of motion tests, and stress relaxation test. The six sessions of high velocity low amplitude spinal manipulative therapy did not significantly affect any of the test measurements among our healthy participant group.

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Joseph, Laya. "Development of Ultra-Wide band 500 MHz – 20 GHz Heterogeneous Multi-Layered Phantom Comprises of Human Skin, Fat and Muscle Tissues for Various Microwaves Based Biomedical Application." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-402458.

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In biomedical applications realistic phantoms are becoming more useful for validation and testing of precursor systems. These artificial phantoms require stable and flexible tissue-mimicking materials with realistic dielectric properties in order to properly model human tissues. We have fabricated a low-water-content, low cost, mechanically and electrically stable, good shelf life and multi-layered heterogeneous phantom consisting of skin, fat and muscle tissues. We have chosen semi-solid type phantom for each tissue layer. The size and thickness of the each layer is chosen based on the average thickness of human tissue. Altering the ingredient composition wisely we can alter its dielectric properties also. By reason of no osmosis occurrence, the tissues can be employed to construct heterogeneous phantoms or even anthropomorphic phantoms without causing any changes in geometry or electrical properties. The performance of the fabricated phantom is carried out using an open-ended coaxial slim probe system by Agilent Technologies. Nearly all previous studies were based on very high frequency( VHF), so we present ultra-wide band (UWB), 500MHz-20GHz multilayered phantoms. We have measured our phantom after 2 month time period and we got quite good results for the dielectric properties without having significant variations. Thus, our fabricated sets of ATE phantom have good long lasting properties with good physical and dielectric stability.

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Rodriguez, Roberta Diehl. "Doença por grãos argirofílicos." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-18062015-113849/.

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Introdução: A doença por grãos argirofílicos (DGA) é uma tauopatia esporádica distinta, bastante frequente, com uma prevalência atingindo 31,3% em centenários, porém pouco reconhecida A manifestação clínica mais comum da DGA é de um comprometimento cognitivo de lenta evolução associado a uma alta frequência de sintomas psiquiátricos. O diagnóstico de DGA é possível somente através da análise do encéfalo post-mortem com os achados das três principais alterações patológicas: grãos argirofílicos, corpúsculos em embrião e pré-emaranhados neuronais. O presente estudo investigou as características demográficas, clínicas e neuropatológicas dos indivíduos com DGA e possíveis associações clínico-patológicas. Métodos: Foram estudados 983 casos (acima de 50 anos de idade) provenientes da amostra do Banco de Encéfalos do Grupo de Estudos em Envelhecimento Cerebral. A avaliação clínica e funcional foi realizada através de uma ampla entrevista semiestruturada respondida por um informante com contato próximo com o paciente. Os participantes foram estratificados conforme a presença de comprometimento cognitivo (de acordo com Escala de Avaliação Clinica da Demência) e, posteriormente, pela presença de DGA em quatro grupos: DGA com e sem comprometimento cognitivo e não-DGA com e sem comprometimento cognitivo. Análise descritiva foi realizada para dados socioeconômicos, genótipo de APOE e variáveis clínico-funcionais, neuropsiquiátricas e neuropatológicas na amostra DGA e em cada grupo. Foi utilizado um modelo de regressão logística multivariada para investigar as associações entre perfil cognitivo e sintomas neuropsiquiátricos com DGA. Resultados: DGA foi identificada em 150 indivíduos (15,1%). Idade avançada e baixo nível socioeconômico foram associados com DGA independente da presença de comprometimento cognitivo. A presença de DGA foi associada a uma redução de 60% na probabilidade de um escore >= 3.8 no Questionário do informante sobre o Declínio Cognitivo do Idoso (OR=0,40; IC de 95% 0,22-0,74; p=0,004). Adicionalmente, o subitem apetite do inventário neuropsiquiátrico foi associado à DGA em indivíduos cognitivamente normais (OR=1,85; IC de 95% 1,09-3,12; p=0,02). Conclusão: A DGA pode preservar a cognição em indivíduos com patologias neurodegenerativas associadas em particular nos casos com patologia tipo Alzheimer concomitante. A investigação dos mecanismos subjacentes a esse efeito pode auxiliar no desenvolvimento de novos tratamentos para a Doença de Alzheimer
Background: Argyrophilic grain disease (AGD) is an underrecognized, distinct, highly frequent sporadic tauopathy, with prevalence reaching 31.3% in centenarians. The most common presentation of AGD is a slowly progressive amnestic mild cognitive impairment, accompanied by high frequency of neuropsychiatric symptoms. AGD can only be diagnosed postmortem by the finding of its three main pathologic features: argyrophilic grains, oligodendrocytic coiled bodies and neuronal pretangles. The present study investigated demographic, clinical, and neuropathological profiles and analyzed clinicopathological associations. Methods: We studied 983 participants (over 50 years of age) from the Brain Bank of the Brazilian Aging Brain study group sample. Clinical and functional evaluation included demographics and a semi-structured interview covering various cognitive domains conducted with a knowledgeable informant. Participants were stratified by cognitive status (based on Clinical Dementia Rating scale), followed by the presence of AGD in four groups: AGD with and without cognitive impairmet, and non-AGD with and without cognitive impairment. Descriptive statistics were used for sociodemographic data, APOE genotypes, and the clinical, cognitive, neuropsychiatric, functional, and neuropathological variables in AGD samples and in each group. We used multivariate logistic regression models to investigate the association between the cognitive status and neuropsychiatric symptoms with AGD. Results: AGD was identified in 150 participants (15.1%). Older age and lower socioeconomic status were associated with AGD independent of cognitive status. Multivariate analyses revealed that AGD was associated with a 60% reduction in the odds of having an IQCODE >= 3.8 (OR = 0.40, 95% CI 0.22-0.74, p = 0.004) and that the NPI sub-item \"appetite and eating abnormalities\" was associated with AGD in controls (OR = 1.85, 95% CI 1.09-3.12, p = 0.02). Conclusion: AGD might preserve cognition in individuals with coexistent neurodegenerative pathologies, in particular those of the Alzheimer-type. Investigating whether the mechanisms underlying this effect could provide novel therapeutic approaches to the treatment of Alzheimer´s disease

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Nascimento, Camila Fernandes. "Caracterização das alterações da proteína TDP-43 durante o envelhecimento normal: uma análise em cérebros humanos postmortem." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-18062015-114710/.

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INTRODUÇÃO: A proteína TDP-43 (Transactive DNA-binding protein 43) é o principal agregado proteico anormal verificado em casos de Degeneração Lobar Frontotemporal (DLFT) e Esclerose Lateral Amiotrófica (ELA). Apesar dos avanços na área, o papel da TDP-43 no envelhecimento normal ainda é pouco compreendido. A falta de indivíduos controles em estudos de associação clinicopatológica com tecido cerebral humano é resultado do alto custo da prática de autópsia mundialmente. O que é um diferencial do Brasil, onde essa prática é obrigatória em casos de morte natural sem causa definida. O Banco de Encéfalos Humanos do Grupo de Estudos em Envelhecimento Cerebral (BEHGEEC) possui grande número de encéfalos de sujeitos sem déficit cognitivo com alta miscigenação étnica e variação de graus de escolaridade. O que possibilita estudos mais aprofundados sobre envelhecimento cerebral humano não-patológico. OBJETIVOS: (1) investigar de maneira sistemática a distribuição dos achados neuropatológicos da TDP-43 no envelhecimento humano normal; (2) caracterizar a distribuição dessa proteína em diferentes áreas encefálicas; (3) explorar associação de características, clínicas, sociodemográficas ou neuropatológicas com o aparecimento das inclusões de TDP-43. MÉTODOS: Foram incluídos participantes com idade acima de 50 anos e classificados clinicamente e anatomopatologicamente como normais. Reação imunoistoquímica contra a conformação anormal da TDP-43 foi realizada em três regiões cerebrais de interesse córtex temporal, amígdala e hipocampo. RESULTADOS: Os agregados de TDP-43 estavam presentes em 10,5% dos indivíduos estudados (n=323). A região mais frequentemente acometida foi a amígdala (85,3% dos casos). O acúmulo de TDP-43 foi associado à idade e raça (p=0,002). Análise de regressão logística demonstrou que indivíduos da raça asiática possuem maior chance de apresentar os agregados de TDP-43 do que caucasianos, independente dos fatores gênero, idade, estágio de Braak para emaranhados neurofibrilares e escolaridade (odds ratio=3,5: intervalo de confiança: 1,41-8,69, p=0,007). CONCLUSÕES: Os resultados sugerem que o acúmulo anormal de TDP-43 aumenta com o avanço da idade e que a amígdala é a região cerebral mais susceptível ao acúmulo desse tipo de inclusão. Como os idosos estudados são cognitivamente normais, sugerimos que indivíduos asiáticos estão protegidos contra os efeitos deletérios da proteína TDP-43 no cérebro. Futuros estudos de associação clinicopatológica e genética em populações de diferentes raças poderão contribuir para identificação de possíveis fatores de proteção contra a expressão clínica dos achados da proteína TDP-43
BACKGROUND: Transactive DNA-binding protein 43 (TDP-43) is the major abnormal aggregate present in Frontotemporal Lobar Degeneration (FTLD) and Amyotrophic Lateral Slcerosis (ALS). Although all the efforts in research in this field, the role played by TDP-43 in normal aging is still unknown. The lack of normal controls in studies focusing on clinicopathological associations is a result of the high cost of autopsy practice worldwide. In Brazil, autopsy is mandatory by law in cases without a certificate. The Brain Bank of the Brazilian Aging Study Group (BBBASG) comprises a large number of cognitively normal elderly subjects highly ethnically admixtured and with broad education attainment. This allow us to further study the non-pathological process of the human aging brain. GOALS: (1) sistematically investigate the distrubution of neuropathological findings of TDP-43 in the normal human brain; (2) characterize the distribution of theses findings in different brain regions; (3) explore clinical, sociodemographics or neuropathological variables that could be associated with TDP-43 inclusion outcome. METHODS: We included participants over 50 years old previously classified cognitively and neuropathologically as normals. Imunnohistochemistry against abnormal form of TDP-43 was performed in three brain regions: temporal cortex, hippocampal formation and amygdala. RESULTS: TDP-43 aggregates were present in 10,5% of the study subjects (n=323). Amygdala was the most frequently affected brain region (85.3% of the cases). TDP-43 accumulation was associated with age at death and race (p=0.002). Logistic regression analysis showed that asians older adults have higher odds of presenting TDP-43 inclusions than caucasians, regardless of gender, age, Braak stage for neurofibrilarly tangles and education attainment (OD=3.5, CI: 1.41-8.69, p=0.007). CONCLUSIONS: Our results suggest that TDP-43 abnormal accumulation increases along aging process and the amygdala is the brain region most susceptible to these alterations. Because we studied cognitively normal elderlies, we suggest that Asians older adults are protected against deleterious effects of TDP-43 in the brain. Future clinicopathological and genetic studies in populations dwelling in different ethnical backgrounds may identify possible protecting factors against the clinical expression of TDP-43 neuropathological findings

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Pradier, Aline. "Evaluation des champs électromagnétiques induits dans les tissus biologiques pour les nouveaux usages et les nouvelles technologies sans fil." Paris 6, 2006. http://www.theses.fr/2006PA066545.

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Ce manuscrit présente une analyse des champs électromagnétiques induits dans les tissus biologiques par les nouveaux usages en télécommunication ainsi que les nouvelles technologies du type UWB. Pour les nouveaux usages, les terminaux se trouvent de plus en plus proches du buste. Ce positionnement doit être pris en compte par les normes. La composition du buste est différente d'une personne à l'autre. Pour cela une étude sur l'influence de la puissance absorbée en fonction de la composition de la personne est menée. Cette étude servira à déterminer un facteur correctif pour valider l'utilisation du liquide équivalent de la tête pour l'étude de la conformité des terminaux près du buste. De plus une nouvelle approche basée sur de l'homogénéisation de tissus et destinée à réduire le volume et le temps de calculs dans les problèmes de dosimétrie numérique sera présentée pour la méthode de la FDTD. Avec les nouvelles technologies comme l'UWB pour des applications dites BAN, les études sont plus en relation avec l'influence du corps sur la propagation du signal. D'un point de vue numérique, il a été nécessaire de trouver des méthodes numériques comme la FDTD pour des signaux UWB. Des mesures dans le cas d'un réseau BAN ont été réalisées.

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Santos, Luiz Augusto Ubirajara. "Efeito da utilização de plasma rico em plaquetas na osteointegração dos enxertos ósseos homólogos criopreservados: estudo histomorfométrico em coelhos." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5140/tde-16082007-160750/.

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As perdas ósseas em alguns seguimentos do sistema músculoesquelético têm sido motivo de grande preocupação na área da Ortopedia e Traumatologia. Propostas de tratamentos com uso de enxertos e fatores de crescimento são descritas ao longo dos anos. Neste estudo avaliamos o efeito do plasma rico em plaquetas -PRP na fase inicial do processo de osteointegração de enxertos ósseos homólogos criopreservados a - 80 °C, em forma de blocos, implantados no côndilo femoral de coelhos. Operamos 19 animais (38 fêmures), onde ambas as técnicas foram aplicadas no mesmo animal em lados alternados. De um lado aplicamos o aloenxerto isolado (Lado 1) e no outro associamos o aloenxerto ao PRP (Lado 2). Após 15 dias, os animais foram sacrificados e os côndilos femorais com as áreas de enxertia analisados pela histomorfometria com o método semiautomático. Não observamos efeito do plasma rico em plaquetas nas áreas de enxertias dos aloenxertos, pois a comparação dos parâmetros histomorfométricos estruturais, de formação e reabsorção não mostraram diferenças significativas.
Bone loss, in some segments of the muscle-skeleton system, are of great concern in the fields of Orthopedics and Traumatology. There are several options of treatment by means of bone grafts and growth factors. In this study we evaluate the effect of platelet rich plasma (PRP) in the initial phase of osteointegration of cryopreserved (- 80 °C) homologous bone grafts, in blocks, implanted in the femoral condyles of rabbits. We operated 19 animals (38 femurs). Both techniques were applied in the same animal in alternate sides. In one side we applied isolated allograft (side 1) and on the contralateral side we added PRP to the allograft (side 2). After 15 days, the animals were sacrificed and the femoral condyles, with the receptor area, were analyzed histomorphometrically (semi-automatic method). We found no effect of the PRP in the receptor. The comparison between the histomorphometric parameters of structural, formation and bone resorption showed no significant differences.

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Vehovský, Radek. "Vliv uživatele na miniaturní antény v mobilních aplikacích." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-219972.

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This master’s thesis deals with user influence on miniature antennas in mobile application. Electrically small antennas including fundamental performance properties and limitations are introduced in the theoretical section of this thesis. This section also deals with microstrip antennas and their common types. The accent is on PIFA antennas, their typical constructions and methods of miniaturization. In the practical section, dual-band PIFA antenna for operation at frequencies of systems GSM900 and GSM1800 is designed with the assistance of electromagnetic field simulator CST Microwave Studio. On this type of antenna, the user influence on impedance matching and radiation pattern in data mode (the user is typing message or browsing with the phone) is investigated. For this purpose the hand phantom, corresponding to author’s right hand, was made from agar based material. For typical position of human hand is designed matching network, which eliminate the user influence and ensure correct function of antenna.

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Spingarn, Camille. "Contribution à la biomécanique de la régénération osseuse : modélisation, simulation et applications." Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAD010/document.

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Cette thèse traite de la modélisation du remodelage osseux. Nous présentons tout d'abord un modèle général continu tenant compte de la réponse cellulaire à un stimulus mécanique. Ce modèle est appliqué à des géométries 2D et 3D macroscopiques afin de se rapprocher des problématiques réelles, ainsi que sur des géométries mésoscopiques d'os trabécullaires en 2D. Cependant la complexité du remodelage osseux ne permet pas d'avoir une approche unique de modélisation. Ainsi, dans un second temps, le cas particulier du remodelage osseux orthodontique est étudié. Un nouveau modèle spécifique est développé tenant compte de l'influence du ligament parodontal sur le remodelage osseux, et intégrant l'influence du taux d'oxygène qui contrôle les évolutions de densités cellulaires. Des données expérimentales in vitro sont extraites de la littérature et servent de données d'entrées du modèle développé afin d'obtenir l'évolution de la densité osseuse alentours d'une racine dentaire cylindrique en 3D
This work deals with modelization of bane remodeling. We present first a madel thal accounts for the cellular res panse to a mechanical stimulus in a general case at a continuous scale. This madel is applied to 2D and 3D geometries at macroscopic scale to mimic real cases, as weil as 2D trabecular-type geometries at mesoscopic scale. However, the complexity of bane remodeling does not allow a unique approach. Th us, the thesis work is focused on the particular case of orthodontie bane re mode ling. A new specifie madel is developed accounting for the influence of the periodontal ligament on orthodontie bane remodeling by integrating the oxygen concentration effect controling the evolutions of cellular densities. The cellular experimental data in vitro are extracted from the literature, and serve as input data of the developed madel in arder to ablain the evolution of bane density around the root of a 3D cylindrical tooth

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Bey, Marie Elena. "The Effect of Pregnancy on the Risk of Injury." Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/22139.

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Körperliche Aktivität während der Schwangerschaft wirkt sich positiv auf die Gesundheit von Mutter und Kind aus. Trotzdem werden Schwangere häufig gewarnt, sich aufgrund der abnehmenden Muskelkraft, den nachgiebigeren Bändern und Sehnen sowie der verschlechterten Stabilität beim Sport verletzen zu können. Um Verletzungen während der Schwangerschaft vorbeugen zu können, wird in dieser Arbeit erstmalig der Einfluss von Schwangerschaft auf den Muskel-Sehnen-Komplex der unteren Extremitäten untersucht. Weiterhin werden der Effekt auf das statische Gleichgewicht und der Einsatz eines Schwangerschaftsgurtes als potentielle Präventionsmaßnahme gegen Sturzunfälle überprüft. Zur Untersuchung des Muskel-Sehnen-Komplexes wurde die Morphologie des m. vastus lateralis, die Muskelkraft der Knieextensoren und die Eigenschaften der Patellasehne am Anfang und am Ende der Schwangerschaft sowie ein halbes Jahr nach der Entbindung mittels Ultraschall und Dynamometrie analysiert. Das Gleichgewicht wurde anhand der Grenzen der Stabilität nach anterior und posterior und anhand des Körperschwankens im ruhigen Stand auf einer Kraftmessplatte bei Schwangeren in den unterschiedlichen Schwangerschaftstrimestern und bei Nicht-Schwangeren mit und ohne Schwangerschaftsgurt beurteilt. Diese Arbeit liefert relevante Erkenntnisse, die für die Beurteilung des Verletzungsrisikos von Schwangeren und für die Entwicklung geeigneter präventiver Maßnahmen nützlich sind. Es wurde zum wiederholten Male bestätigt, dass Schwangerschaft zu einer Verschlechterung der posturalen Stabilität führt. Ein Schwangerschaftsgurt stellt jedoch keine geeignete Methode zur Verbesserung der Stabilität dar. Während Muskelmorphologie und Sehnensteifigkeit keinen negativen Einfluss zeigen, könnte die zunehmende Sehnenruhelänge zu einer vergrößerten Gelenkbeweglichkeit beitragen und das Risiko für Verletzungen und Stürze erhöhen.
Physical activity during pregnancy has beneficial effects on maternal and fetal health. However, pregnant women are frequently cautioned when exercising since a loss in muscle strength, an increased compliance of ligaments and tendons as well as impairments in postural stability are assumed to lead to injuries in pregnant women. This thesis investigates for the first time the effect of pregnancy on the muscle-tendon unit of the lower extremities for the prevention of injuries during pregnancy. Furthermore, this thesis analyzes the effect of pregnancy on static postural stability and examines whether a maternity support belt is an appropriate method for fall prevention in pregnant women. To investigate the muscle-tendon unit, the morphology of the vastus lateralis muscle, muscle strength of the knee extensors and the properties of the patellar tendon were analyzed in the early and late stage of pregnancy as well as six months after delivery by means of ultrasound and dynamometry. Balance ability was assessed determining the limits of stability in the anterior and posterior directions and the postural sway during motionless upright standing on a force plate in pregnant women in different trimesters of pregnancy and in non-pregnant women with and without maternity support belt. This thesis provides relevant evidence for the assessment of the risk of injury in pregnant women and the development of appropriate prevention strategies. It confirmed that pregnancy is accompanied by impaired postural stability. However, a maternity support belt is not an appropriate method to improve stability. While muscle morphology and tendon stiffness were not negatively affected during pregnancy, the increase in tendon rest length might contribute to an increased joint mobility that may increase the fall and injury risk.

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Cunha, Rui Duarte Teixeira. "Estado da Arte na Utilização e Preservação dos Aloenxertos Osteocartilagíneos em Ortopedia." Master's thesis, 2019. http://hdl.handle.net/10316/89566.

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Trabalho Final do Mestrado Integrado em Medicina apresentado à Faculdade de Medicina
Osteochondral lesions represent one of the largest groups of injuries worldwide due to arthrosis, trauma, oncological surgery or joint infection.Cartilage damage is responsible for the morbidity associated with these lesions and the regenerative potential of articular cartilage is insufficient. Mainly because of the formation of fibrocartilage and its inability to restore normal joint function, with the lesion progressing and often the necessity of a total or partial arthroplasty as definitive treatment.The larger the area of the lesion, the lower the indication for autologous therapies by iatrogeny at the place of harvest. As an effective alternative, allogeneic transplants that preserve viable hyaline cartilage can restore the joint function.This hyaline cartilage must be mature, with viable chondrocytes, which can maintain metabolic activity and its extracellular matrix to be successful in the medium/long term.Several methods have been developed and tested which differences are based on the conservation protocol, temperature, medium and the duration of conservation that can ensure counts above 70% of viable chondrocytes.After a critical evaluation of the available literature it can be concluded that Missouri Osteochondral Allograft Preservation System (MOPS) has superior results when compared to the standard of care that is used worldwide by tissue banks and other protocols studied in this work. .
As lesões osteocartilagineas representam um dos maiores grupos de lesões a nível mundial sendo por artrose, trauma, cirurgia oncológica ou infeção articular.O dano cartilagíneo é responsável pela morbilidade associada a estas lesões e o potencial regenerativo da cartilagem articular é insuficiente. Principalmente pela formação de fibrocartilagem e pela sua incapacidade de restituir uma função articular normal, havendo progressão da lesão e recorrendo-se muitas vezes a artroplastias totais ou parciais como tratamento definitivo.Quanto maior a área da lesão, menor a indicação das terapêuticas autólogas por iatrogenia no local da colheita. Como alternativa eficaz, surgem os transplantes alógenos que apresentam cartilagem hialina viável e restituem a funcionalidade articular.Esta cartilagem hialina tem de ser madura, com condrócitos viáveis, que mantenham a atividade metabólica e a sua matriz extracelular para terem sucesso a médio/longo prazo. Foram desenvolvidos e testados vários métodos que se diferenciam pelo protocolo de conservação dos mesmos, no qual a temperatura, o meio e a duração da conservação com contagem condrocitária viável acima dos 70%, são pontos chave.Após uma avaliação crítica da literatura disponível conclui-se que Missouri Osteochondral Allograft Preservation System (MOPS) apresenta resultados superiores quando comparado ao método padrão utilizado pelos bancos de ossos a nível mundial e a outros protocolos estudados neste trabalho. .

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Tsoumpekos, Georgios. "big bang, a novel regulator of tissue growth in Drosophila melanogaster." Doctoral thesis, 2015. https://tud.qucosa.de/id/qucosa%3A29434.

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Multicellular organisms need to control their size throughout development and adult life in the face of challenges such as rapid growth. Unraveling the mechanisms that regulate tissue growth in epithelial tissues, in order to generate organs of correct size and proportion, remains a crucial goal of developmental biology. A suitable epithelial tissue for studying tissue growth in Drosophila, is the proliferative monolayer epithelial sheet of imaginal wing discs, which gives rise to the adult wing. The Hippo signaling pathway regulates tissue growth in wing development. There are several observations that link tissue growth/Hippo signaling with cell polarity and the actin cytoskeletal organization. The aim of this thesis was the study of the interplay between cell polarity, cytoskeletal organization and tissue growth. To gain further insight into how apical polarity proteins regulate tissue growth, an enhancer/suppressor screen that was previously conducted in our lab by Linda Nemetschke, was used. The screen was based on the modification of a dominant smaller wing phenotype induced upon overexpression of CrbextraTM-GFP. One of the enhancers identified in this screen is a gene called big bang (bbg). The absence of bbg results in smaller wings with a slower cell cycle and increased apoptosis in wing discs. bbg encodes a protein expressed in the apical cortex in wing disc cells and is required for the proper localization of apical proteins, like Crb, in wing disc epithelia. Bbg is also in the same complex with Spaghetti Squash (Sqh) in the apical cortex of the wing disc epithelia. sqh encodes an actin-binding protein that has actin cross-linking and contractile properties. Bbg stabilizes Sqh in the apical compartment of the cell. It is reported that both Crb and Sqh regulate tissue growth through the Hippo signaling pathway. In conclusion, Bbg regulates wing tissue growth, acting as a scaffolding molecule, through the proper localization of apical components of the cells like Crb and the cytoskeletal component Sqh.

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De, Carvalho Diana Elisa. "TIME VARYING GENDER AND PASSIVE TISSUE RESPONSES TO PROLONGED DRIVING." Thesis, 2008. http://hdl.handle.net/10012/3859.

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Background: Prolonged sitting in an automobile seat may alter the passive tissue stiffness of the lumbar spine differentially in males and females. Gender specific ergonomic interventions may be indicated for the automobile seat design. Purpose: To compare time-varying passive lumbar spine stiffness in response to a two hour simulated driving trial with time-varying lumbar spine and pelvic postures during sitting in an automobile seat. A secondary purpose was to investigate gender differences in lumbar spine stiffness, seat/occupant pressure profile, discomfort rating and posture. Methods: Twenty (10 males, 10 females) subjects with no recent history of back pain were recruited from a university population. Participants completed a simulated driving task for two hours. Passive lumbar range of motion was measured on a customized frictionless jig before, halfway through and at the end of the two-hour driving trial. Changes in the passive moment-angle curves were quantified using the transition zone slopes, breakpoints and maximum lumbar flexion angles. Lumbar spine and pelvic postures were monitored continuously during the simulated driving trial with average and maximum lumbar flexion angles as well as pelvic tilt angles being calculated. Results: Both men and women initially demonstrated an increase in transitional zone stiffness after 1 hour of sitting. After 2 hours of sitting, transitional zone stiffness was found to increase in males and decrease in females. During sitting, women were found to sit with significantly greater lumbar flexion than males and to significantly change the amount of lumbar flexion over the 2 hour period of simulated driving. Conclusions: Postural differences during simulated driving were demonstrated between genders in this study. In order to prevent injury to the passive elements of the spine during prolonged driving, gender specific ergonomic interventions, such as improved lumbar support, are indicated for the automobile seat.

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Mcnamara, Lorraine. "Nutrient concentration of inner bark tissue in pine trees in Mpumalanga in relation to baboon damage." Thesis, 2006. http://hdl.handle.net/10539/1493.

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Faculty of Science School of Animal Plant and Enviromental Sciences 0404336v lmcnamara@gpf.co.za
Pine saw timber plantation forestry on the Eastern Escarpment of South Africa contributes significantly to the economy of the country. Losses to plantation value through fire, insects and disease, and particularly over the last decade, losses due to baboon damage are of serious concern. Anecdotal evidence indicated that baboons damage pine trees shortly following pruning operations and at certain times of the year. A perception existed that damage has increased dramatically, yet no documented evidence to this effect is available. As a result two physiological studies were undertaken to investigate whether changes in nutrient concentration of inner bark tissues of pine trees on the Eastern Escarpment of South Africa, act as triggers for baboon damage. A literature review was also undertaken to document the extent of baboon damage, tree volume and associated economic costs. A comparison was made with Zimbabwe, where baboon damage is quoted to be a severe threat to the continued viability of plantation forestry. The first study investigated changes in nutrient concentration of the soft, inner bark tissue of Pinus patula, in response to pruning measured in five year old plantations in the Mpumalanga Province, South Africa. Samples of tissues were collected from pruned and unpruned trees at 2, 7, 14 and 28 days after 26% of the live crown had been removed in the pruning treatment. Results indicated that live pruning of Pinus patula did not influence nutrient concentration of inner bark tissues at set intervals post pruning. Treatment differences of aggregate data for sample interval showed that potassium concentration increased by 0.03% whereas magnesium concentration decreased by 0.02% following pruning. Aggregate data for treatment showed that phosphorus, carbohydrates (fructose, glucose, sucrose and starch), boron and nitrogen concentration, and moisture content of inner bark tissues varied during the short time period of the study. Variations are attributed to iv the commencement of growth, translocation of nutrients from needles and branches and possibly moisture stress. Results from the study do not support anecdotal evidence that baboon damage to pine plantations which increases shortly after pruning operations is as a direct physiological response to the pruning event. In this study it is much more likely that changes in nutrient concentrations coincided with a remobilization of resources in response to seasonal triggers. In the second study, nutrient concentrations of the inner bark of Pinus patula and Pinus taeda growing on the Eastern Escarpment of South Africa were studied over a seasonal cycle in order to investigate the allegations that baboon damage in the plantations was related to the degree of nutrient remobilization. Significant differences were found in phosphorus concentration and moisture content across seasons and between baboon damaged and undamaged trees. Undamaged Pinus taeda trees recorded the highest phosphorus levels in April 2003 (0.13%). Moisture content was lowest in damaged Pinus patula trees in August 2003 (57%). Anecdotal evidence that baboon damage to pine trees on the Eastern Escarpment of Mpumalanga increases prior to the growing season is supported by the significant changes in inner bark tissue concentration. Nutrient translocation prior to needle fall alters inner bark nutrient concentration, as does moisture stress and demand for nutrients prior to cambial activity. Pine bark is easier to peel during periods of peak cambial activity. These factors are discussed as they may trigger baboon damage. Significantly higher inner bark tissue concentrations of sucrose (4.25 versus 2.61%), starch (4.75 versus 2.84%) and nitrogen (0.61 versus 0.49%) in Pinus taeda compared with Pinus patula, supports anecdotal evidence that Pinus taeda is preferentially damaged by baboons. Baboon damaged trees contained higher concentrations of zinc (30.4 versus 22.3 ppm) and calcium (0.26 versus 0.20%), and lower concentrations of sucrose (2.95 versus 3.91%) and starch (3.21 versus v 4.39%) than undamaged trees, which was attributed to resource allocation to wound response and not that baboons selected trees with higher concentrations of zinc or calcium. The variability of inner bark tissue concentration due to a number of factors highlights that baboon damage in pine plantations is not readily answered, and remains a complex problem. A literature review was undertaken of reported baboon damage occurrence and intensity of damage, following statements that baboon damage to pine plantations is rapidly escalating in the Mpumalanga Province, South Africa. The extent and intensity of baboon damage from the first reported damage (1960’s) until current levels are documented. A comparison is made between Zimbabwe and South Africa where the baboon damage is viewed as a serious problem. The extent of baboon damage in Zimbabwe, expressed as the total percentage of area damaged by baboons as a function of the total area planted to pine for the period 2000-2004 has escalated from 10.8 to 13.3% despite harvesting activities removing damaged trees (Fergusson, 2004). The total area with reported baboon damage in Zimbabwe amounted to 5 317 hectares in 2004 (Fergusson, 2004). In South Africa baboon damage has increased markedly from the first reports of 300 hectares in 1980 (Bigalke, 1980) to 7 641 hectares in 2004. The average percentage of trees damaged in affected compartments is 20.4% with the percentage increasing from 17.2 to 23.6% from 2002-2004. Pinus taeda appears to be the most severely affected species with Pinus elliottii showing increasing levels of damage in many compartments in 2004. Quantifying the value lost by baboon damage to the industry requires reliable assessment methods that are cost effective to implement. Assessment methods need to take into account the position of the damage on the stem, and resultant saw log value that is lost. Assessment methods implemented in South Africa and Zimbabwe are described, and results given by method applied. A standard assessment method is required for comparisons to be made between areas vi with baboon damage. An investigation in Zimbabwe highlighted significant differences between standing tree volume estimations (4.98 – 7.59 m3/ha, with various methods), and actual volume losses (50.45 m3/ha) (Ngorima et. al., 2002). The associated Rand value loss determined by the South African assessment method in 2004 was in excess of 20 million Rand. This estimated loss in revenue does not include losses of incremental growth due to the damage, re-establishment costs, loss of thinning and clearfelling product revenue due to timber wastage, or losses experienced in down line processing at the saw mill. The extent of the baboon damage problem warrants proactive management, continued monitoring and investment into research in order to gain a better understanding of the problem. The increase in the extent of baboon damage from early documented figures is most alarming, showing that the baboon damage problem continues to grow.

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Chen, Kai-Chia, and 陳楷佳. "The effectiveness of common physical therapy interventions on soft tissue hardness in patients with low back pain." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/59781969412157805422.

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碩士
國立陽明大學
物理治療暨輔助科技學系
101
Background and purpose: It was estimated that approximately 60% to 80% people experienced low back pain (LBP) and associated symptoms at least once in their lives. Symptoms including pain and back muscle hardness at the low back region may affect patients’ quality of life and even result in disability. Soft tissue mobilization (STM), stretching exercises (SE) and superficial heat (SH) are common interventions for treating the symptoms associated with LBP. The therapeutic effects of these interventions have been partially proven in the literature. However, no evidences were documented on their effects on decreasing soft tissue hardness in patients with LBP. In addition, the relationship between the improvement of pain intensity and decrease of the soft tissue hardness has not been investigated in previous studies. The purposes of this randomized controlled trial were 1) to determine which intervention had greatest improvement in decreasing soft tissue hardness, pain, pressure pain threshold, lumbar mobility, and perceived improvement in subjects with LBP; and 2) to examine the relationships between decrease of the soft tissue hardness and improvement of the pain intensity and pressure pain threshold. Methods: This study is a prospective, randomized control trial. We recruited sixty patients with LBP. All subjects were randomly assigned into either the STM group (N=20), SE group (N=20) or SH group (N=20). The STM group received soft tissue mobilization on low back region, including lumbar erector spinae, quadratus lumborum, and thoracolumbar fascia. The SE group was instructed by a physical therapist to perform seven stretching exercises (hold 15s in each movement, 10 times per movement). The SH group received heat therapy by a moist heating pad on the low back region with a one kilogram sandbag on top of the pad. The treatment session for all three groups lasted for twenty minutes. All subjects only received one treatment session. The outcome included soft tissue hardness measured by the Myotonometer, pain intensity recorded by a numeric rating scale (NRS), pressure pain threshold (PPT) measured by an algometer, and lumbar mobility measured by the Spinal Mouse. Statistical analysis: Two-way repeated measures analysis of covariance (ANCOVA) with appropriate post-hoc pairwise comparisons was used to compare the within- and between-groups differences for each outcome measure. The significant level was set at 0.017 by Bonferroni adjustment. Pearson correlation coefficients were used to examine the relationships between the decrease of the soft tissue hardness and improvement of the pain intensity and pressure pain threshold. The significant level was set at 0.05. Results: Sixty subjects met the inclusion criteria and agreed to participate in this study. There were 4 men and 16 women (mean age= 45.25 11.93 years) in the STM group; 7 men and 13 women (mean age= 49.10 11.04 years) in the SE group; 4 men and 14 women (mean age= 48.60 13.86 years) in the SH group. No statistical differences among three groups were found at the baseline. After one treatment session, all three groups demonstrated significant improvement in pain intensity when compared to the baseline data (p<0.001). The STM group demonstrated significantly better improvement on decreasing pain intensity than the SH group (p=0.001). The STM group and SE group also had significantly greater improvement on soft tissue hardness than the SH group (p<0.001 and p=0.007).The STM group had significantly more increase in PPT than both the ST group (p=0.001) and the SH group (p<0.001). No significant improvement of lumbar mobility could be found after one session of treatment in all three groups. In addition, the relationships between decrease of soft tissue hardness and improvement of pain intensity and pressure pain threshold were found statistically significant (p<0.05). Discussions and Conclusions: Soft tissue mobilization and stretching exercises influenced the soft tissue deeper than the superficial heat, so these two groups demonstrated significantly better treatment effects than the heat group on decreasing soft tissue hardness, reducing pain intensity, increasing pressure pain threshold, and achieving greater patient's perceived improvement. Therapeutic effect of soft tissue mobilization comes from biomechanical, neurophysiological, and psychological aspects. Studies suggest that a mechanical force is necessary to initiate a chain of neurophysiological responses which produce the outcomes associated with manual therapy. Stretching exercises exert a lower imposed load on tissues, which promotes an adaptation of the parallel elastic component. Reduction in the hardness might be attributed to an acute change in the rearrangement of collagen fibers. Stretching evoked a stress relaxation response that was characterized by a gradual decrease in passive torque from the stretched musculotendinous unit. Superficial heat may provide physiological benefits of increasing tissue circulation and temperature. However, it did not produce significant changes on pressure pain threshold and soft tissue hardness. In this study, we found positive relationships between decrease of soft tissue hardness and improvement of pain intensity. This finding also helps to explain the analgesic effects of soft tissue mobilization and stretching exercise interventions. In conclusion, soft tissue mobilization was the best intervention compared to stretching and heat for treating patients with low back pain.

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43

Lee, Wen-Li, and 李文立. "Ultrasonic Liver Tissues Analysis by Fractal Feature Vector based on M-band Wavelet Transform." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/74736330068163289006.

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博士
國立清華大學
電機工程學系
91
The focus of this dissertation is the feature extraction of ultrasonic liver images. The feature extraction is essential in a computer vision system for diagnosis of medical images. We propose a fractal feature vector based on M-band wavelet transform to classify ultrasonic liver images─normal liver, cirrhosis, and hepatoma. The proposed feature extraction algorithm is based on the spatial-frequency decomposition and fractal geometry. And, various classification algorithms based on respective texture measurements and filter banks are presented and tested. Classifications for the three sets of ultrasonic liver images reveal that the fractal feature vector based on M-band wavelet transform is trustworthy. A hierarchical classifier, which is based on the proposed feature extraction algorithm is at least 96.7% accurate in the distinction between normal and abnormal liver images and is at least 93.6% accurate in the distinction between cirrhosis and hepatoma liver images. Additionally, the criterion for feature selection is specified and employed for performance comparisons herein. In supervised classification, we also propose a modified computation of fractal dimension since the estimation of the fractal dimension is crucial in fractal geometry. The adopted estimation approach is based on box-counting. However, the scheme, which is easily disturbed by noise, produced many non-negligible plateaus that cause underestimate. A more robust and efficient computation of the fractal dimension is verified from experimental results. Finally, we applied the proposed multiresolution fractal feature vector to segment suspicious abnormal regions of ultrasonic liver images. Segmentation of various liver diseases reveals that the fractal feature vector based on multiresolution analysis is reliable. A quantitative characterization based on the proposed unsupervised segmentation algorithm can be utilized to establish an automatic computer-aided diagnostic system. As well, to increase the visual interpretation capability of ultrasonic liver image for junior physicians, an off-line learning system can be developed to investigate the visual criteria.

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Alhaddad, A. G., Khairun N. Ramli, Raed A. Abd-Alhameed, and Dawei Zhou. "Interaction Between Electromagnetic Field and Human Body for Dual Band Balanced Antenna Using Hybrid Computational Method." 2010. http://hdl.handle.net/10454/4788.

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yes
This paper describes a hybrid computational method which efficiently models the interaction between a small antenna placed in proximity with the human body. Results for several test cases of placed in different locations on the body are presented and discussed. The near and far fields were incorporated into the study to provide a full understanding of the impact on human tissue. The cumulative distribution function of the radiation efficiency and absorbed power is also provided. The antennas are assumed to be operating over the 2.4 GHz and 5.2 GHz WLAN frequencies.

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45

Kong, Deqing. "Dynamics of cell contacts during cell intercalation in epithelial tissue elongation of Drosophila embryos." Doctoral thesis, 2017. http://hdl.handle.net/11858/00-1735-0000-0023-3F72-5.

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46

Xing, Yi-ting, and 謝亦婷. "Effect of culture factors on callus induction and sporophyte regeneration and of tissue of Davallia mariesii Moore ex bak." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/17980743669465264940.

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碩士
大同大學
生物工程學系(所)
104
Davallia mariesii Moore ex Bak. is a slow-growing perennial medicinal fern. The rhizoma of Davallia contain with high antioxidants such as phenolic compound, triterpenes compound. A proliferation protocol of callus with high total phenolic content of Davallia mariesii Moore ex Bak by liquid culture has been established in this study. The rhizomes from sporophytes of D. mariesii cut into fine pieces were cultured in 1/2 Murashige and Skoog (MS) liquid media supplemented with different plant growth regulators combination of 2,4- dichlorophenoxy acetic acid (2,4-D), 6-benzyladenine (BA), thidiazuron (TDZ), gibberellic acid (GA), indolebutyric acid (IBA), and picloram. The green callus developed from tissue pieces when cultured in medium containing 4.54 μM TDZ and 0.9 μM 2,4-D has best result of 28 combinations after 30 days. The average growth rate was 2.5 times than the initial inoculation and total phenolic content was 31.8 μg gallic acid equivalent / mg DW. The average 1 g fresh weight of callus can regenerated approximately 1700 sporophytes after 4 months culture. The best inoculation density for sporophytes proliferation in 1L bubble column bioreactor was 1 % compared with 0.6、2、3 %. The growth ratio of sporophytes was 158.63 % and total phenolic content was 24. 4 μg gallic acid equivalent / mg DW. The total phenolic content in sporophytes was increased to 34.8 μg gallic acid equivalent / mg DW when the medium salt ratio of NH4NO3 / KNO3 μM was changed to 10/20 NH4NO3 / KNO3.

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47

Gomes, Adrian Neil. "A comparative study of spinal manipulative therapy and spinal manipulative therapy combined with soft tissue therapy in the management of mechanical low back pain." Thesis, 1997. http://hdl.handle.net/10321/2728.

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Dissertation submitted in partial compliance with the requirements for the Masters Degree in Technology: Chiropractic at Technikon Natal, 1997.
There have been few studies performed to determine the combined effects of spinal manipulative therapy with other modalities known to have beneficial physiological effects, especially in terms of mechanical low back pain (Ottenbacher and Difabio 1985).
M

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48

Daskalou, Dean. "Osteopathic treatments and the techniques used in the treatment of acute mechanical low back pain." Thesis, 2003. https://vuir.vu.edu.au/909/.

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The efficacy of osteopathic treatments used in acute low back pain (LBP) is largely unknown. The study examined the number of student osteopathic treatments for uncomplicated acute LBP, as well as the specific osteopathic techniques, and combinations of treatments most commonly used. One hundred and ninety nine patient files from the Victoria University (VU) student clinic were examined. The most popular combinations of techniques used were soft tissue (ST) and High Velocity Low Amplitude thrust (HVLA) 10.77%. The most commonly used individual technique was ST, incorporated in 75.4% of all treatments performed. This study illustrated the average number of treatments as well as treatment techniques and the combinations of techniques student osteopaths used in treating acute LBP at the VU student clinic. This minor thesis was written by a post-graduate student as part of the requirements of the Master of Health Science (Osteopathy) program.

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49

Van, Wyk Anna Susanna. "Exploring bridge-grafting as technique te restore growth in girdled Ocotea bullata and Curtisia dentata in the Southern Cape forest area." Diss., 2017. http://hdl.handle.net/10500/23277.

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In South Africa, there is a growing concern regarding the sustainability of bark harvesting due to the reduced availability of medicinal trees in natural areas and the slow growing and slow-reproducing nature of South Africa’s indigenous trees, of which some have specific habitat requirements and a limited distribution. With an estimated 80% of all Africans in South Africa still relying on plant material for their basic healthcare needs, approximately 200 000 traditional healers and an estimated 63 000 commercial harvesters, medicinal plants are being exploited to extinction. The aim of the study was to determine whether bridge-grafting could be used to restore growth in girdled Ocotea bullata and Curtisia dentata trees as these two medicinal tree species are listed on the South African Red List as ‘endangered’ and ‘near threatened’ due to overexploitation. These trees were also historically used in furniture production and general carpentry, which increased these trees’ vulnerability to extinction. Bridge-grafting is a technique widely described in horticultural literature but has not been used to restore growth in medicinal tree species with extensive harvesting damage. Metabolomics as analytical method is a relatively new science, but it is very useful, accurate and repeatable in obtaining knowledge on the metabolites present in a plant, and for determining the concentrations of metabolites. NMR metabolomics is, however, not sensitive enough to quantify metabolites with very low concentrations such as plant hormones. The results achieved showed that O. bullata and C. dentata responded differently to girdling and bridge-grafting regarding location of callus initiation, callus development, rate of callus development, basal shoot initiation and development and their sucrose source-sink relationships. NMR metabolomics showed that seasonality was an important factor affecting metabolite responses in both species. NMR metabolomics also showed that after one year, there were no differences in responses above and below the girdle wounds, nor were there differences between the grafted trees and the normal control trees. iv Although the method of bridge-grafting was successful in restoring the growth of O. bullata and C. dentata with this study, much more research needs to be conducted to prevent endangered girdled medicinal trees from becoming extinct, to maintain tree species diversity, genetic diversity and biodiversity.
School of Environmental Sciences
M. Sc. (Nature Conservation)

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50

Jayaprakash, *. "Automated Selection of Hyper-Parameters in Diffuse Optical Tomographic Image Reconstruction." Thesis, 2013. http://hdl.handle.net/2005/3276.

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Diffuse optical tomography is a promising imaging modality that provides functional information of the soft biological tissues, with prime imaging applications including breast and brain tissue in-vivo. This modality uses near infrared light( 600nm-900nm) as the probing media, giving an advantage of being non-ionizing imaging modality. The image reconstruction problem in diffuse optical tomography is typically posed as a least-squares problem that minimizes the difference between experimental and modeled data with respect to optical properties. This problem is non-linear and ill-posed, due to multiple scattering of the near infrared light in the biological tissues, leading to infinitely many possible solutions. The traditional methods employ a regularization term to constrain the solution space as well as stabilize the solution, with Tikhonov type regularization being the most popular one. The choice of this regularization parameter, also known as hyper parameter, dictates the reconstructed optical image quality and is typically chosen empirically or based on prior experience. In this thesis, a simple back projection type image reconstruction algorithm is taken up, as they are known to provide computationally efficient solution compared to regularized solutions. In these algorithms, the hyper parameter becomes equivalent to filter factor and choice of which is typically dependent on the sampling interval used for acquiring data in each projection and the angle of projection. Determining these parameters for diffuse optical tomography is not so straightforward and requires usage of advanced computational models. In this thesis, a computationally efficient simplex Method based optimization scheme for automatically finding this filter factor is proposed and its performances is evaluated through numerical and experimental phantom data. As back projection type algorithms are approximations to traditional methods, the absolute quantitative accuracy of the reconstructed optical properties is poor .In scenarios, like dynamic imaging, where the emphasis is on recovering relative difference in the optical properties, these algorithms are effective in comparison to traditional methods, with an added advantage being highly computationally efficient. In the second part of this thesis, this hyper parameter choice for traditional Tikhonov type regularization is attempted with the help of Least-Squares QR-decompisition (LSQR) method. The established techniques that enable the automated choice of hyper parameters include Generalized Cross-Validation(GCV) and regularized Minimal Residual Method(MRM), where both of them come with higher over head of computation time, making it prohibitive to be used in the real-time. The proposed LSQR algorithm uses bidiagonalization of the system matrix to result in less computational cost. The proposed LSQR-based algorithm for automated choice of hyper parameter is compared with MRM methods and is proven to be computationally optimal technique through numerical and experimental phantom cases.

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