Xie, Xinhui. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 163-193). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Graduation date: 1993

No description available.

Understanding the effect of food abundance on feeding behavior can benefit conservation efforts in many ways, such as to determine whether impacted environments need food supplementation, whether different locations of threatened species contain different food abundances, or whether reintroduction sites are missing key components of a species’ diet. I studied the relationship between feeding behavior and food abundance in the Lower Keys marsh rabbit (Sylvilagus palustris hefneri), an endangered subspecies endemic to the lower Florida Keys. Specifically, my study set out to measure the relative abundance of the primary plants within the natural habitat of the Lower Keys marsh rabbit and estimate the proportion of each of these plants within the rabbit’s diet. With this information, I tested the following hypotheses: first, the Lower Keys marsh rabbit selectively feeds on specific plants; second, that diet does not differ among sites; and third, that diet is not affected by food abundance. Using stable isotope analysis, I determined that two plants were prominent in the rabbit’s diet: a shrub, Borrichia frutescens, and a grass, Spartina spartinae. These two species were prominent in the rabbit’s diet in most patches, even where they were relatively rare, suggesting the rabbits are indeed selectively feeding on these species. In addition, although diet did differ among patches, selective feeding was apparent in all cases. Overall, this study determined that certain food types are important food sources for the federally endangered Lower Keys marsh rabbit and that these rabbits do not feed on plants based on plant abundance. This knowledge can be directly applied to reintroduction and restoration efforts for the Lower Keys marsh rabbit. More generally, the methods used in this study can be applied to other species of concern in order to address questions associated with diet requirements and foraging behavior.

Subspecific taxonomic designations solely based on morphological characters can often lead to erroneous assumptions about the evolutionary history of populations. This study sought to investigate evolutionary questions and conservation implications associated with morphological subspecific designations of island populations. To this end, I focused my attention on the Lower Keys of Florida, a unique chain of islands with well-known geologic history and rich in endemic, endangered subspecies. I employed genetic analyses to evaluate historical variation and contemporary restriction of gene flow between the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) and its sister mainland taxa. A Bayesian phylogeny using 1063 base pairs of the mitochondrial cytochrome b gene did not recover reciprocal monophyly of the three named subspecies, and a 95% statistical parsimony haplotype network showed haplotypes being shared among subspecies. Furthermore, clustering analyses using 10 microsatellite loci identified a break within the Lower Keys, separating the western Lower Keys from the island of Big Pine Key. Surprisingly, Big Pine Key grouped with mainland populations and exhibits higher genetic diversity than the western Lower Keys islands. These unexpected findings suggest either a stepping-stone colonization pattern or recent gene flow between the mainland and Big Pine Key via natural dispersal or undocumented man-mediated transfers. Although these results suggest that subspecies designations within S. palustris are unwarranted, this study supports the designation western Lower Keys population as a discrete unit of conservation with regard to both DPS and ESU criteria. The importance of using several lines of evidence to uncover the evolutionary history of populations and implications for the conservation of island populations are discussed.

Made available in DSpace on 2016-01-26T18:55:32Z (GMT). No. of bitstreams: 1 DISSERTACAO_ Magda - 21-08-2011- corrigido.pdf: 2313731 bytes, checksum: 7e4161e3e3a18ed9159672a8d9d78833 (MD5) Previous issue date: 2011-06-30 / The aim of this study was to evaluate the effectiveness of the linseed oil (OL) in different preparations (oral, topically, oral and topically combined) in the treatment of the kerato-conjunctivitis sicca (KCS) experimentally induced in rabbits. Twenty white male rabbits of the New Zeland race were used. They were divided in 4 groups of 5 animals each: Group C (Control); Group OLO (OL oral); Group OLT (OL topically); and Group OLOT (OL oral and topically). The rabbits were evaluated weekly by the Shirmer Tear Test (TLS), Flourescein Test (TF) and the Rose-Bengal Test (TRB), and a ocular impression cytology exam was done once a month, and at the end of the experiment the rabbits were sacrificed to a histopathological analysis. There was a significant improvement in the parameters analysed (TLS,TF and TRB) in all the groups that used OL, but there was differences in the performance of each group. In the TLS the groups OLO and OLT showed larger values than the OLOT group from the 7th week to the end of the experiment. In TF the group OLT reverted the incidence of corneal ulcers earlier than the other groups starting on the 5th week. In TRB, the group OLO and also the OLT showed normal values starting on the 9th week, while the group OLOT only on the last week. In the cytological findings the group OLT showed a more advanced stage of inflammation on the 4th and 8th week and also on the hispathological findings of this group showed a more advanced stage of edema, degeneration and necrosis than the other groups. It wasn´t observed any collateral damage due the use of OL. The results analyzed showed that the OL, topically or oral, was efficient on the treatment of CCS experimentally induced in rabbits and can be and excellent adjuvant, natural and safe, in the treatment of this illness / O objetivo deste estudo foi avaliar a eficácia do óleo de semente de linhaça (OL) em várias preparações (oral, tópica, oral e tópica associadas) no tratamento da ceratoconjuntivite seca (CCS) induzida experimentalmente em coelhos. Foram utilizados vinte coelhos brancos machos da raça Nova Zelândia. Os animais foram divididos em 4 grupos com 5 animais cada: Grupo C (controle) animais hígidos; Grupo OLO (OL via oral); Grupo OLT (OL por via tópica) e Grupo OLOT (OL via oral e tópica). Os coelhos foram avaliados semanalmente pelo Teste de Lágrima de Schirmer (TLS), Teste de Fluoresceína (TF) e Teste de Rosa Bengala (TRB), uma vez por mês pelo exame de citologia de impressão ocular, e ao final do experimento foram sacrificados para análise histopatológica. Houve melhora clínica significativa nos parâmetros analisados (TLS, TF e TRB) em todos os grupos que usaram OL, porém, houve diferenças no desempenho de cada grupo. Os Grupos OLO e OLT apresentaram valores superiores do TLS, quando comparado com o Grupo OLOT a partir da 7ª semana até o final da observação. No TF o grupo OLT reverteu mais precocemente, a partir da 5ª semana, a incidência de úlceras na córnea, do que os demais grupos. Os Grupos OLO e OLT apresentaram TRB negativos para CCS a partir da 9ª semana, enquanto o grupo OLOT somente na última semana. Nos achados citológicos o grupo OLT apresentou um maior grau de inflamação na 4ª e 8ª semana e também nos achados histopatológicos esse grupo apresentou um maior grau de edema, degeneração e necrose do que os demais grupos. Não foi observado nenhum efeito colateral com o uso do OL. Os resultados analisados demonstraram que o OL, tanto por via oral como tópica, foi eficaz no tratamento de CCS induzida experimentalmente em coelhos e pode ser um adjuvante, natural, no tratamento desta enfermidade.

Made available in DSpace on 2016-07-18T17:53:08Z (GMT). No. of bitstreams: 1 DISSERTACAO_ Magda - 21-08-2011- corrigido.pdf: 2313731 bytes, checksum: 7e4161e3e3a18ed9159672a8d9d78833 (MD5) Previous issue date: 2011-06-30 / The aim of this study was to evaluate the effectiveness of the linseed oil (OL) in different preparations (oral, topically, oral and topically combined) in the treatment of the kerato-conjunctivitis sicca (KCS) experimentally induced in rabbits. Twenty white male rabbits of the New Zeland race were used. They were divided in 4 groups of 5 animals each: Group C (Control); Group OLO (OL oral); Group OLT (OL topically); and Group OLOT (OL oral and topically). The rabbits were evaluated weekly by the Shirmer Tear Test (TLS), Flourescein Test (TF) and the Rose-Bengal Test (TRB), and a ocular impression cytology exam was done once a month, and at the end of the experiment the rabbits were sacrificed to a histopathological analysis. There was a significant improvement in the parameters analysed (TLS,TF and TRB) in all the groups that used OL, but there was differences in the performance of each group. In the TLS the groups OLO and OLT showed larger values than the OLOT group from the 7th week to the end of the experiment. In TF the group OLT reverted the incidence of corneal ulcers earlier than the other groups starting on the 5th week. In TRB, the group OLO and also the OLT showed normal values starting on the 9th week, while the group OLOT only on the last week. In the cytological findings the group OLT showed a more advanced stage of inflammation on the 4th and 8th week and also on the hispathological findings of this group showed a more advanced stage of edema, degeneration and necrosis than the other groups. It wasn´t observed any collateral damage due the use of OL. The results analyzed showed that the OL, topically or oral, was efficient on the treatment of CCS experimentally induced in rabbits and can be and excellent adjuvant, natural and safe, in the treatment of this illness / O objetivo deste estudo foi avaliar a eficácia do óleo de semente de linhaça (OL) em várias preparações (oral, tópica, oral e tópica associadas) no tratamento da ceratoconjuntivite seca (CCS) induzida experimentalmente em coelhos. Foram utilizados vinte coelhos brancos machos da raça Nova Zelândia. Os animais foram divididos em 4 grupos com 5 animais cada: Grupo C (controle) animais hígidos; Grupo OLO (OL via oral); Grupo OLT (OL por via tópica) e Grupo OLOT (OL via oral e tópica). Os coelhos foram avaliados semanalmente pelo Teste de Lágrima de Schirmer (TLS), Teste de Fluoresceína (TF) e Teste de Rosa Bengala (TRB), uma vez por mês pelo exame de citologia de impressão ocular, e ao final do experimento foram sacrificados para análise histopatológica. Houve melhora clínica significativa nos parâmetros analisados (TLS, TF e TRB) em todos os grupos que usaram OL, porém, houve diferenças no desempenho de cada grupo. Os Grupos OLO e OLT apresentaram valores superiores do TLS, quando comparado com o Grupo OLOT a partir da 7ª semana até o final da observação. No TF o grupo OLT reverteu mais precocemente, a partir da 5ª semana, a incidência de úlceras na córnea, do que os demais grupos. Os Grupos OLO e OLT apresentaram TRB negativos para CCS a partir da 9ª semana, enquanto o grupo OLOT somente na última semana. Nos achados citológicos o grupo OLT apresentou um maior grau de inflamação na 4ª e 8ª semana e também nos achados histopatológicos esse grupo apresentou um maior grau de edema, degeneração e necrose do que os demais grupos. Não foi observado nenhum efeito colateral com o uso do OL. Os resultados analisados demonstraram que o OL, tanto por via oral como tópica, foi eficaz no tratamento de CCS induzida experimentalmente em coelhos e pode ser um adjuvante, natural, no tratamento desta enfermidade.

No description available.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

A insuficiência glótica é uma condição clínica caracterizada pelo fechamento inadequado das pregas vocais durante a fonação ou a deglutição. Nos casos mais leves, os pacientes são geralmente encaminhados para tratamento fonoterápico. Nos casos com sintomas mais importantes ou insucesso na fonoterapia, o tratamento cirúrgico se faz necessário. A melhor abordagem cirúrgica para a insuficiência glótica vem sendo debatida há mais de um século. As injeções laringoplásticas são procedimentos tecnicamente simples e com possibilidade de realização sob regime ambulatorial, no entanto seus resultados não são sempre previsíveis. Esses procedimentos também trazem consigo a possibilidade de rigidez da mucosa vocal por causa da reação inflamatória ao material utilizado. Apesar do crescente interesse por procedimentos ambulatoriais na laringologia e da popularização das injeções laringoplásticas, é sabido que se carece de materiais de melhor qualidade para resultados ainda mais consistentes. O surgimento do biopolímero de cana-de-açúcar (BPCA) e as pesquisas sobre seu uso em outras especialidades médicas apontaram para a possibilidade de que o referido material possa ser adequado ao uso nas injeções laringoplásticas. O presente trabalho foi desenvolvido para estudar a reação inflamatória causada pela injeção do BPCA na prega vocal de coelhos e comparar com a reação causada pela hidroxiapatita de cálcio (HCa). Para tal, foi procedida a injeção de 0,1mL HCa e BPCA na forma de gel nas pregas vocais direita e esquerda, respectivamente, de coelhos machos adultos da raça Oryctolagus cuniculus. Os coelhos foram divididos em dois grupos de 15, os quais foram sacrificados com 3 e 12 semanas. Após o sacrifício, foi feita a remoção e o processamento do material a ser estudado. Nos cortes histológicos foram avaliados os parâmetros de intensidade e composição celular do processo inflamatório, neovascularização, fibrogênese e alterações inflamatórias na mucosa vocal. Observou-se que a HCa e o BPCA desencadearam reação inflamatória por células do grupo linfomononuclear semelhantes em ambos os períodos analisados. A HCa desencadeou uma reação inflamatória por células gigantes intensa em todas as amostras e significativamente mais importante que o BPCA em ambos os períodos estudados. O BPCA apresentou reação inflamatória por células do grupo polimorfonucleares mais intensa do que a HCa apenas 3 semanas após a injeção. Não houve diferença entre as duas substâncias no que concerne à formação de tecido fibroso no leito cirúrgico após 3 e 12 semanas. Houve uma maior neoformação vascular com a injeção de BPCA comparado com a HCa após 3 semanas do procedimento. Não houve diferença estatística nessa variável após 12 semanas. Com relação às alterações inflamatórias da mucosa, não houve diferença significativa entre as substâncias nos três parâmetros estudados: integridade do epitélio, infiltrado inflamatório e presença de fibras colágenas na região submucosa. Conclui-se que, enquanto a HCa desencadeia uma reação inflamatória mediada por células gigantes, mais intensa e duradoura, o BPCA apresenta uma resposta por polimorfonucleares, assim como uma neoformação vascular mais importantes apenas após 3 semanas da injeção. Outros estudos devem ser realizados para avaliar o potencial do uso do BPCA no tratamento da insuficiência glótica / The glottal insufficiency is a clinical condition featured by abnormal closure of vocal folds during the process of phonation or deglutition. In most mild, cases patients are usually referred to speech therapy. In those cases presenting more relevant symptoms or failure in speech therapy, the surgical procedure is mandatory. The best surgical approach for glottal insufficiency has been debated over the past one hundred years. Laryngoplastic injections are technically simple procedures and possible to be performed in an outpatient basis, however their results are not always predictable. Such procedures may also present stiffness in the vocal mucosa due to the inflammatory reaction to the material which has been used. Despite of the fact that the growing interest in outpatient basis procedures in laryngology as well as the popularization of laryngoplastic injections, it is well known the lack of better quality materials for inducing much more consistent results. The arising of sugarcane biopolymer (SCB) along with researches on its use in other medical specialties demonstrated that there is a possibility for adequately using the mentioned material in laryngoplastic injections. The present work has been developed for the purpose of studying the inflammatory reaction which is caused by sugarcane biopolymer (SCB) injected in rabbits vocal folds as well as comparing to that reaction caused by calcium hydroxyapatite (HCa). For this experiment adult male rabbits from the race Oryctolagus cuniculus have been used, thus, 0.1 ml of HCa and of SCB in gel form were injected in their right and left vocal folds respectively. Rabbits have been divided into two groups of 15 each which were sacrificed at 3 and 12 weeks. After sacrifice, the vocal cords were removed and processed in order to be studied. Parameters as intensity and cellular composition in the inflammatory process, neovascularization, fibrogenesis as well as inflammatory alterations of vocal mucosa have been analyzed in histological pieces. It has been observed that HCa and SCB triggered an inflammatory reaction by lymphomononuclear group cells which are similar in the analysis of both periods. HCa triggered an inflammatory reaction by giant cells being intense in all of the samples and significantly more relevant as compared to SCB in the study of both periods. SCB presented an inflammatory reaction by polymorphonuclear group cells which was more intense as compared to HCa in just three weeks after injection. There was no difference between the two substances concerning the fibrous tissue building-up after three and twelve weeks. There was a larger vascular neoformation when injecting SCB as compared to HCa injection three weeks after procedure. There was no statistical difference in such a variable after twelve weeks. In respect of mucosa inflammatory changes, there was no significant difference between the substances by studying those three parameters as follows: epithelial integrity, inflammatory infiltrate and the presence of collagenous fibers in the submucosal region. In conclusion, while HCa triggers an inflammatory reaction mediated by giant cells which is more intense and lasting, SCB in its turn presents a more prevalent response by polymorphonuclear cells as well as by a vascular neoformation just three weeks after injection. Other studies should be done in order to evaluate the potential use of SCB in treating glottal insufficiency