Thesis (doctoral)--Karolinska Institutet, Stockholm, 1993. / Added t.p. with thesis statement inserted. Includes bibliographical references.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18643号 / 医博第3942号 / 新制||医||1006(附属図書館) / 31557 / 京都大学大学院医学研究科医学専攻 / (主査)教授 木村 剛, 教授 三森 経世, 教授 山下 潤 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Many of the anabolic effects of growth hormone (GH) are indirect, occurring through GH-stimulated production of insulin-like growth factor-I (IGF-I) by the liver. As well as being GH regulated, plasma IGF-I concentrations have been demonstrated to be dependent upon protein nutrition, with low protein diets being associated with reduced plasma IGF-I concentrations. This effect cannot be reversed by GH, suggesting that liver sensitivity to GH is impaired. To investigate the mechanisms through which protein supply affects GH sensitivity, primary cultures of ovine hepatocytes were grown in defined media. In a first experiment the media contained various fractions (0.2, 1.0, 5.0) of portal vein amino acid concentrations in fed sheep. In the second 24h incubation period, unstimulated IGF-I secretion was highly sensitive the concentration of amino acids in the media, with significantly greater release of basal IGF-I in 5x compared to either 1x (P<0.05) or 0.2x amino acid containing media. In a second series of experiments the effects of specific amino acid depletions was examined. Methionine depletion of 0.2x portal amino acid concentrations ablated the GH response second 24h of culture without affecting basal IGF-I release. By comparison ³H-leucine incorporation into secreted protein, following 20 hours of culture in defined media was significantly reduced in 0.2x aa (P<0.01) and 1.0x aa (P<0.05) media compared with 5.0x aa media, however secretory protein synthesis was unaffected by methionine depletion to 0.2x portal concentrations. The results suggest that amino acid availability regulates both basal and GH stimulated IGF-I release in ovine hepatocytes. Furthermore reducing methionine concentrations in the culture media to 0.2x portal concentrations diminishes GH response without compromising protein secretion.

Although there is strong evidence that thyroid tumors occur more frequently in females than in males, few studies have investigated the role sex hormones play in thyroid carcinogenesis, especially the role of estrogen (E2). This laboratory has previously shown that estrogen receptors (ERs) exist in thyroid papillary carcinoma cells. Continuing along this line of research, we studied the role of E2 and its receptors on the regulation of human thyroid cancer. / In conclusion, we have demonstrated (1) a novel mechanism by which E2 contributes to the proliferation and growth of thyroid cancer cells, (2) that E2 influences the expression of ERalpha and ERbeta differently, causing an imbalance between them, which may change the biological behavior of thyroid cancer cells, giving them the ability to proliferate and resist apoptosis by influencing the level of ERK1/2 activity and subsequently the ratio of anti-apoptotic Bcl-2 to pro-apoptotic Bax, and (3) that the subcellular localization of ERalpha and ERbeta may be a factor that contributes to the differing pathogeneses of papillary and anaplastic thyroid cancers. / To further clarify the mechanism by which E2 promotes cellular proliferation in thyroid cancer cells, we studied the localization of ERalpha and ERbeta in both KAT5 and anaplastic carcinoma cells (FRO) by immunofluorescence staining and by immunoblotting of the proteins in subcellular fractions. Cell proliferation and apoptosis were examined together with the expression of selected apoptotic proteins such as Bax, AIF and cytochrome c. We showed that the subcellular localization of ERalpha and ERbeta differed in papillary and anaplastic thyroid cancer. E2 administration led to an increase in the level of ERalpha in the nuclei of papillary cancer cells while the levels of ERbeta remained unchanged. However, the level of mitochondrial ERbeta surpassed that of ERalpha in anaplastic cancer cells. We also showed that E2 affected caspase-dependent and/or independent apoptosis via ERs in thyroid cancers. / We first studied the molecular pathways by which E2 promotes cellular proliferation in thyroid cancer cells using a human thyroid cancer cell line (KAT5) treated with E2, a selective E2 alpha receptor (ERalpha) agonist (PPT), a selective E2 beta receptor (ERbeta) agonist (DPN), an ERalpha antagonist (MPP), an E2 antagonist (ICI182780) and siRNA, which blocks ERalpha and ERbeta, by MTT assay, DNA fragmentation ELISA, BrdU cell proliferation assay and Western blot. We found that E2 and PPT gradually promoted cell proliferation by increasing the expression of ERalpha and by up-regulating the expression of Bcl-2 and pERK1/2. In contrast, we found that DPN had a negative effect on cell growth by enhancing the expression of ERbeta and Bax and by down-regulating pERK1/2 expression. At the same time, blocking ERalpha significantly reduced the E2-mediated Bcl-2 and pERK1/2 expression. On the other hand, blocking ERbeta markedly enhanced their expression. These results suggest that E2 regulates cellular growth of KAT5 cells by an ER-ERK1/2-MAPK pathway and also that E2 affects mitochondrial homeostasis. / Zeng, Qiang. / "September 2007." / Adviser: George Gong Chen. / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4616. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 136-154). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

Orientador: Maria José Hitomi Nagata / Banca: Mário Taba Junior / Banca: Álvaro Francisco Bosco / Banca: Ronaldo Célio Mariano / Banca: Valdir Gouveia Garcia / Resumo: O objetivo do presente trabalho foi avaliar, histologicamente, a influência da associação do plasma rico em plaquetas (PRP) ao enxerto de osso autógeno (OA) no reparo ósseo de defeitos de tamanho crítico (DTC) em calvárias de coelhos. Sessenta coelhos foram divididos em 3 grupos: C (controle), OA (osso autógeno) e OA/PRP (osso autógeno associado ao plasma rico em plaquetas). Um defeito de tamanho crítico, com 15 mm de diâmetro, foi criado na calvária de cada animal. No Grupo C, o defeito foi preenchido somente com coágulo sanguíneo. No Grupo OA, o defeito foi preenchido com osso autógeno particulado. No Grupo OA/PRP, o defeito foi preenchido com osso autógeno particulado associado ao PRP. Todos os grupos foram divididos em subgrupos (n = 10) para eutanásia aos 30 ou 90 dias pós-operatórios. Foram realizadas análises histológica e histométrica. A quantidade de osso neoformado foi calculada como uma porcentagem da área total do defeito original. Os dados em porcentagem foram transformados em raiz quadrada para análise estatística (ANOVA, teste t, p<0,05). Aos 30 dias pós-operatórios, o Grupo OA/PRP apresentou uma quantidade significativamente maior de osso neoformado que o Grupo OA (64,44% e 46,88%, respectivamente). Aos 90 dias, todos os espécimes dos Grupos OA/PRP e OA mostraram fechamento ósseo completo do defeito, com quantidades similares de osso neoformado (77,9% e 75%, respectivamente). Dentro dos limites deste trabalho, pode-se concluir que o PRP acelerou o processo de reparo do enxerto de osso autógeno em defeitos de tamanho crítico em calvária de coelhos. / Abstract: The purpose of this study was to histologically analyze the effect of platelet-rich plasma (PRP) on bone healing in an autogenous bone graft placed in surgically created criticalsize defects (CSD) in rabbit calvaria. 60 rabbits were divided into 3 groups: C (control); AB (autogenous bone graft) and AB/PRP (autogenous bone graft with platelet-rich plasma). A 15 mm diameter CSD was created in the calvarium of each animal. In Group C the defect was filled by blood clot only. In Group AB the defect was filled with particulate autogenous bone. In Group PRP it was filled with particulate autogenous bone in combination with platelet-rich plasma. All groups were divided into subgroups (n=10) and euthanized at either 30 or 90 days post-operative. Histometric, using image analysis software, and histologic analyses were performed. Amount of new bone was calculated as a percentage of the total area of the original defect. Percentage data were transformed into square root for statistical analysis (ANOVA, t test, p<0.05). At 30 days post-op, Group AB/PRP had a statistically greater amount of bone formation than Group AB (64.44% and 46.88%, respectively). At 90 days, complete bone regeneration of the defect was seen in all specimens of Groups AB/PRP and AB, with similar amounts of newly formed bone (77.9% and 75%, respectively). Within the limits of this study, it can be concluded that PRP accelerated the healing of autogenous bone graft in critical-size defects in rabbit calvaria. / Doutor

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2006. / Härtill 4 uppsatser.

Made available in DSpace on 2014-06-11T19:33:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-09Bitstream added on 2014-06-13T20:44:59Z : No. of bitstreams: 1 melo_lgn_dr_araca.pdf: 931001 bytes, checksum: c60fdb1de080f3e5dcb844fe719ab023 (MD5) / O objetivo do presente trabalho foi avaliar, histologicamente, a influência da associação do plasma rico em plaquetas (PRP) ao enxerto de osso autógeno (OA) no reparo ósseo de defeitos de tamanho crítico (DTC) em calvárias de coelhos. Sessenta coelhos foram divididos em 3 grupos: C (controle), OA (osso autógeno) e OA/PRP (osso autógeno associado ao plasma rico em plaquetas). Um defeito de tamanho crítico, com 15 mm de diâmetro, foi criado na calvária de cada animal. No Grupo C, o defeito foi preenchido somente com coágulo sanguíneo. No Grupo OA, o defeito foi preenchido com osso autógeno particulado. No Grupo OA/PRP, o defeito foi preenchido com osso autógeno particulado associado ao PRP. Todos os grupos foram divididos em subgrupos (n = 10) para eutanásia aos 30 ou 90 dias pós-operatórios. Foram realizadas análises histológica e histométrica. A quantidade de osso neoformado foi calculada como uma porcentagem da área total do defeito original. Os dados em porcentagem foram transformados em raiz quadrada para análise estatística (ANOVA, teste t, p<0,05). Aos 30 dias pós-operatórios, o Grupo OA/PRP apresentou uma quantidade significativamente maior de osso neoformado que o Grupo OA (64,44% e 46,88%, respectivamente). Aos 90 dias, todos os espécimes dos Grupos OA/PRP e OA mostraram fechamento ósseo completo do defeito, com quantidades similares de osso neoformado (77,9% e 75%, respectivamente). Dentro dos limites deste trabalho, pode-se concluir que o PRP acelerou o processo de reparo do enxerto de osso autógeno em defeitos de tamanho crítico em calvária de coelhos. / The purpose of this study was to histologically analyze the effect of platelet-rich plasma (PRP) on bone healing in an autogenous bone graft placed in surgically created criticalsize defects (CSD) in rabbit calvaria. 60 rabbits were divided into 3 groups: C (control); AB (autogenous bone graft) and AB/PRP (autogenous bone graft with platelet-rich plasma). A 15 mm diameter CSD was created in the calvarium of each animal. In Group C the defect was filled by blood clot only. In Group AB the defect was filled with particulate autogenous bone. In Group PRP it was filled with particulate autogenous bone in combination with platelet-rich plasma. All groups were divided into subgroups (n=10) and euthanized at either 30 or 90 days post-operative. Histometric, using image analysis software, and histologic analyses were performed. Amount of new bone was calculated as a percentage of the total area of the original defect. Percentage data were transformed into square root for statistical analysis (ANOVA, t test, p<0.05). At 30 days post-op, Group AB/PRP had a statistically greater amount of bone formation than Group AB (64.44% and 46.88%, respectively). At 90 days, complete bone regeneration of the defect was seen in all specimens of Groups AB/PRP and AB, with similar amounts of newly formed bone (77.9% and 75%, respectively). Within the limits of this study, it can be concluded that PRP accelerated the healing of autogenous bone graft in critical-size defects in rabbit calvaria.

Orientador: Maria José Hitomi Nagata / Banca: Maurício Guimarães Araújo / Banca: Luiz Alberto Milanezi / Resumo: Objetivo: O propósito deste estudo foi avaliar, histologicamente, a influência do Plasma Rico em Plaquetas (PRP) no reparo ósseo de defeitos de tamanho crítico (DTC) criados cirurgicamente em calvárias de ratos. Material e Método: 32 ratos foram divididos em 2 grupos: C (controle) e PRP (Plasma Rico em Plaquetas). Um DTC de 8 mm de diâmetro foi criado na calvária de cada animal. No Grupo C, o defeito foi preenchido somente com coágulo sangüíneo. No Grupo PRP, o defeito foi preenchido com Plasma Rico em Plaquetas. Cada grupo foi subdividido para eutanásia em 4 ou 12 semanas pós-operatórias (n=8). Foram realizadas análises histológica e histométrica. A quantidade de osso neoformado foi calculada como uma proporção da área total do defeito original. Esses valores foram transformados em arcoseno para a análise estatística (ANOVA, Tukey, p < 0.05). Resultados: Nenhum defeito reparou completamente com tecido ósseo. O Grupo PRP apresentou significativamente mais neoformação óssea que o Grupo C, tanto em 4 semanas (17,68% e 7,20%, respectivamente) como em 12 semanas (24,69% e 11,65%, respectivamente) pós-operatórias. Conclusão: Dentro dos limites deste estudo, pode-se concluir que o PRP aumentou significativamente o reparo ósseo de defeitos de tamanho crítico em calvárias de ratos. / Abstract: The purpose of this study was to histologically analyze the influence of Platelet Rich Plasma (PRP) on bone healing in surgically created critical-size-defects (CSD) in rat calvaria. 32 rats were divided into 2 groups: C (control) and PRP (Platelet Rich Plasma). An 8 mm diameter CSD was created in the calvarium of each animal. In Group C the defect was filled by blood clot only. In Group PRP it was filled with Platelet Rich Plasma. Both groups were divided into subgroups (n=8) and euthanized at either 4 or 12 weeks post-operative. Histometric, using image analysis software, and histologic analyses were performed. Amount of new bone was calculated as percentage of total area of original defect. Percentage data were transformed into arccosine for statistical analysis (ANOVA, Tukey, p < 0.05). No defect completely regenerated with bone. Group PRP had a statistically greater amount of bone formation than Group C at both 4 (17.68% and 7.20%, respectively) and 12 weeks (24.69% and 11.65%, respectively) post-operative. Within the limits of this study, it can be concluded that PRP significantly enhanced bone healing in critical-size-defects in rat calvaria. / Mestre