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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
621

Fator de crescimento endotelial vascular (VEGF): concentrações séricas e teciduais em gestações ectópicas ampulares e a profundidade da invasão trofoblástica / Vascular endothelial growth factor (VEGF): Serum and tissue concentration in ampular pregnancies and the depth of trophoblastic invasion

Décio Roberto Kamio Teshima 11 November 2015 (has links)
Objetivo: Avaliar a correlação entre a concentração sérica e a expressão tecidual do fator de crescimento endotelial vascular (VEGF) na interface materno embrionária e avaliar a associação entre a profundidade da invasão trofoblástica e a expressão tecidual do VEGF em gestações ectópicas ampulares. Métodos: Estudo prospectivo com 34 mulheres com o diagnóstico de gestação ectópica ampular espontaneamente concebidas, submetidas à salpingectomia no período de 11 de julho de 2012 a 19 de agosto de 2013. Os critérios de exclusão foram: diagnóstico de gestação tubária não ampular, impossibilidade de coleta de sangue para a dosagem do VEGF sérico, da análise anatomopatológica ou da dosagem do VEGF na peça cirúrgica. Após a confirmação diagnóstica de gestação tubária e antes da realização da salpingectomia foram dosadas as concentrações séricas maternas de VEGF pela técnica de luminex. Após o procedimento cirúrgico foi analisada a expressão tecidual de VEGF por imuno-histoquímica e pela técnica de point-counting. Histologicamente, a invasão trofoblástica na parede tubária foi classificada em grau I: limitada à mucosa da tuba uterina; grau II: até a camada muscular; grau III: invasão de toda a espessura da tuba uterina. Resultados: 8 pacientes apresentaram invasão grau I, 7 pacientes com grau II e 19 com invasão grau III. Não se observou diferença estatisticamente significativa na associação entre o VEGF tecidual e os diferentes graus de invasão trofoblástica (p= 0,621) e a correlação do VEGF tecidual com a sua dosagem sérica pelo coeficiente de Spearman (Rho = -0,057) foi fraca (p= 0,748). Foi realizado modelo de regressão logística para comparar o desempenho do VEGF tecidual como fator de predição da profundidade da invasão do trofoblasto na parede tubária, comparando o grau I vs II e III e o grau III vs I e II e não houve diferença estatisticamente significativa. Conclusões: em gestações ectópicas ampulares, a profundidade da invasão do tecido trofoblástico na parede tubária não está associada com a concentração tecidual do VEGF e não há correlação entre as suas dosagens sérica e tecidual / Objetive: To evaluate the correlation between serum concentration and tissue expression of vascular endothelial growth factor (VEGF) at the feto-maternal interface and to associate the depth of trophoblastic invasion into the tubal wall with tissue VEGF in ampullary pregnancies. Methods: A prospective study was conducted on 34 spontaneously conceived ampullary ectopic pregnancies that were submitted to salpingectomy between July 11th, 2012 and August 19th, 2013. Exclusion criteria were: diagnosis of not ampullary pregnancy, impossibility of collecting blood sample for serum VEGF determination, impossibility of either anatomopathological or tissue VEGF analysis. Maternal serum VEGF concentrations were measured after the diagnosis confirmation and before salpingectomy. After surgery, tissue VEGF expression was measured by immunohistocemistry and point counting technique. Histologically, trophoblastic invasion into the tubal wall was classified as grade I when limited to the tubal mucosa, grade II when reaching the muscle layer and grade III when comprising the full thickness of the tubal wall. Results: 8 patients had tubal infiltration grade I, 7 had grade II and 19 had grade III infiltration. Depth of trophoblastic invasion was not associated with tissue VEGF expression (p= 0.621). The correlation between tissue expression and serum VEGF concentration was not present (Spearman\'s coefficient, Rho = -0.057) (p= 0.748). Logistic regression showed that tissue VEGF expression was not predictor of trophoblastic invasion and there was not statistically significant difference when comparing grade I vs II and III and grade III vs I and II. Conclusions: in ampullary pregnancies, the depth of trophoblastic penetration into the tubal wall is not associated with tissue VEGF expression. Serum VEGF do not show any correlation with tissue expression
622

Fator de crescimento endotelial vascular (VEGF): concentrações séricas e teciduais em gestações ectópicas ampulares e a profundidade da invasão trofoblástica / Vascular endothelial growth factor (VEGF): Serum and tissue concentration in ampular pregnancies and the depth of trophoblastic invasion

Teshima, Décio Roberto Kamio 11 November 2015 (has links)
Objetivo: Avaliar a correlação entre a concentração sérica e a expressão tecidual do fator de crescimento endotelial vascular (VEGF) na interface materno embrionária e avaliar a associação entre a profundidade da invasão trofoblástica e a expressão tecidual do VEGF em gestações ectópicas ampulares. Métodos: Estudo prospectivo com 34 mulheres com o diagnóstico de gestação ectópica ampular espontaneamente concebidas, submetidas à salpingectomia no período de 11 de julho de 2012 a 19 de agosto de 2013. Os critérios de exclusão foram: diagnóstico de gestação tubária não ampular, impossibilidade de coleta de sangue para a dosagem do VEGF sérico, da análise anatomopatológica ou da dosagem do VEGF na peça cirúrgica. Após a confirmação diagnóstica de gestação tubária e antes da realização da salpingectomia foram dosadas as concentrações séricas maternas de VEGF pela técnica de luminex. Após o procedimento cirúrgico foi analisada a expressão tecidual de VEGF por imuno-histoquímica e pela técnica de point-counting. Histologicamente, a invasão trofoblástica na parede tubária foi classificada em grau I: limitada à mucosa da tuba uterina; grau II: até a camada muscular; grau III: invasão de toda a espessura da tuba uterina. Resultados: 8 pacientes apresentaram invasão grau I, 7 pacientes com grau II e 19 com invasão grau III. Não se observou diferença estatisticamente significativa na associação entre o VEGF tecidual e os diferentes graus de invasão trofoblástica (p= 0,621) e a correlação do VEGF tecidual com a sua dosagem sérica pelo coeficiente de Spearman (Rho = -0,057) foi fraca (p= 0,748). Foi realizado modelo de regressão logística para comparar o desempenho do VEGF tecidual como fator de predição da profundidade da invasão do trofoblasto na parede tubária, comparando o grau I vs II e III e o grau III vs I e II e não houve diferença estatisticamente significativa. Conclusões: em gestações ectópicas ampulares, a profundidade da invasão do tecido trofoblástico na parede tubária não está associada com a concentração tecidual do VEGF e não há correlação entre as suas dosagens sérica e tecidual / Objetive: To evaluate the correlation between serum concentration and tissue expression of vascular endothelial growth factor (VEGF) at the feto-maternal interface and to associate the depth of trophoblastic invasion into the tubal wall with tissue VEGF in ampullary pregnancies. Methods: A prospective study was conducted on 34 spontaneously conceived ampullary ectopic pregnancies that were submitted to salpingectomy between July 11th, 2012 and August 19th, 2013. Exclusion criteria were: diagnosis of not ampullary pregnancy, impossibility of collecting blood sample for serum VEGF determination, impossibility of either anatomopathological or tissue VEGF analysis. Maternal serum VEGF concentrations were measured after the diagnosis confirmation and before salpingectomy. After surgery, tissue VEGF expression was measured by immunohistocemistry and point counting technique. Histologically, trophoblastic invasion into the tubal wall was classified as grade I when limited to the tubal mucosa, grade II when reaching the muscle layer and grade III when comprising the full thickness of the tubal wall. Results: 8 patients had tubal infiltration grade I, 7 had grade II and 19 had grade III infiltration. Depth of trophoblastic invasion was not associated with tissue VEGF expression (p= 0.621). The correlation between tissue expression and serum VEGF concentration was not present (Spearman\'s coefficient, Rho = -0.057) (p= 0.748). Logistic regression showed that tissue VEGF expression was not predictor of trophoblastic invasion and there was not statistically significant difference when comparing grade I vs II and III and grade III vs I and II. Conclusions: in ampullary pregnancies, the depth of trophoblastic penetration into the tubal wall is not associated with tissue VEGF expression. Serum VEGF do not show any correlation with tissue expression
623

NFκB independent pathway activation of rheumatoid arthritis FLS by macrophage migration inhibitory factor (MIF)

Lacey, Derek January 2003 (has links)
Abstract not available
624

Complementary investigations of the molecular biology of cancer : assessment of the role of Grb7 in the proliferation and migration of breast cancer cells; and prediction and validation of microRNA targets involved in cancer

Webster, Rebecca January 2008 (has links)
[Truncated abstract] For this thesis, the molecular biology of cancer was approached from two directions. Firstly, an investigation was conducted on the role of growth factor receptor-bound protein 7 (Grb7) in breast cancer. Grb7 is an adapter molecule that binds to a variety of proteins, including the growth factor receptor and proto-oncogene, ErbB2, and mediates signalling to downstream pathways. It has been linked to cell migration and an invasive phenotype, and is of interest as a therapeutic target. To investigate the role of Grb7 in breast cancer, preliminary experiments were performed that, firstly, determined the expression of wild-type Grb7 and a splice variant, Grb7V, in a range of cell lines, and secondly, aided the development of a protocol for treating cells with short interfering RNA (siRNA) against Grb7 and the ErbB ligand, heregulin (HRG), in a cell system appropriate for measuring the functional outcomes. Using this protocol in conjunction with CellTitre (CT) proliferation assays, it was demonstrated that Grb7 does not play a role in the proliferation of either unstimulated or HRG-stimulated SK-BR-3 breast cancer cells. Furthermore, using the protocol in conjunction with Boyden chamber migration assays, it was shown that inhibition of Grb7 expression has a slight stimulatory effect on HRG-stimulated SK-BR-3 cell migration. Thus, Grb7 was found to play only a minor role in the migration of SK-BR-3 cells, suggesting that it is not an ideal anti-cancer target for breast cancers modelled by this cell system. Concurrently, a second investigation was conducted, which similarly sought insight into the molecular biology of cancer, but adopted a more strategic approach. ... These results provide evidence for a biologically significant role for the miR-7-mediated regulation of EGFR expression. A microarray experiment was also performed to identify genes that were down-regulated following treatment with miR-7 compared to NS precursor. Of 248 down-regulated genes, including EGFR, 37 promising new miR-7 target candidates were identified. Functional clustering of down-regulated genes and promising target candidates suggested that miR-7 may have functionally-related targets involved in processes including cell motility and brain-associated functions. This investigation thus yielded a program capable of accurately predicting a miRNA target not predicted by any other target prediction program, verified a previously unknown miRNA:target interaction with functional consequences in cancer cells and provided the first steps towards investigating miR-7-mediated regulation in greater depth. Furthermore, EGFR was, to our knowledge, the first example of a verified miRNA target with target sites that are not conserved across mammals, an observation with important implications for computational target prediction and the evolution of miRNA regulatory systems. In addition, the demonstrated growth inhibitory and cytotoxic effects of miR-7 on lung cancer cells raise the possibility of a miR-7-based therapeutic for the treatment of EGFR-overexpressing tumours.
625

Bone Metabolism in Men

Gillberg, Peter January 2001 (has links)
<p>In this thesis, the importance of the growth hormone (GH)/insulin-like growth factor (IGF) system and sex steroids for male bone metabolism has been investigated, and the effects of continuous low dose GH replacement in GH deficient (GHD) adults. In a population-based sample of men, positive correlations were found between bone mineral density (BMD) and IGF-I, IGF-II, IGF binding protein (IGFBP)-3 and the testosterone/sex hormone binding globulin (SHBG) ratio. Serum IGFBP-3 and testosterone levels and weight accounted for 34% to 48% of the variation in BMD at different sites. Compared to healthy age matched controls, men with idiopathic osteoporosis had lower estradiol/SHBG ratio and higher SHBG levels. There were no differences between the groups in serum levels of IGF-I, IGFBP-3, 24 hour cumulated GH secretion or peak GH secretion. In the patients, there was a positive correlation between the estradiol/SHBG ratio and BMD in femoral neck. Treatment of patients and controls with GH 0.8 mg/day for one week resulted in similar increases in serum markers for bone turnover in both groups. Several positive correlations between indices of GH secretion and markers for bone turnover were found in the patients. Men with idiopathic osteoporosis were treated with GH, continuously (0.4 mg/day) or intermittently (0.8 mg/day for two weeks every third month), for two years followed by one year of follow-up. After two years, the BMD and bone mineral content in lumbar spine and total body and serum osteocalcin levels were increased in both groups. This increase was sustained one year post treatment. Treatment of GHD adults with a low fixed dose of GH (0.17 mg/day) for three months, resulted in increases in serum IGF-I and IGFBP-3 levels and lean body mass, and a reduction in fat mass and total and low-density lipoprotein cholesterol levels. These beneficial effects were accomplished without serious side effects. These findings indicate that: i) the sex hormone and GH/IGF systems are important in male bone metabolism, ii) a combination of subtle disturbances in these two systems could contribute to the development of male idiopathic osteoporosis, iii) GH treatment could be considered as a treatment option in this condition.</p>
626

Osteoporosis in chronic liver disease

Ormarsdóttir, Sif January 2001 (has links)
<p>Ormarsdóttir, S. 2001. Osteoporosis in Chronic Liver Disease. Acta Universitatis Upsaliensis. <i>Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine</i> 1037. 60 pp. Uppsala. ISBN 91-554-5021-0. </p><p>Osteoporosis is a well-known and frequently reported complication of chronic liver disease (CLD) with a high fracture rate contributing to significant morbidity after liver transplantation. The pathogenesis is unknown and controversy exists about many risk factors for osteoporosis in CLD. </p><p>In the present thesis, bone mineral density (BMD) was found to be significantly lower at the lumbar spine (<i>p</i><0.01) in a cohort of patients with CLD compared with age- and gender -matched individuals. Osteoporosis was found in 30% of the patients and 15% of the controls, respectively. Low body mass index (BMI), corticosteroid treatment, prothrombin time, age and female gender were independent risk factors for osteoporosis in the patients. </p><p>In a follow-up study, 43 of 72 patients were available for a second BMD measurement 25 months (median) after the first. Bone loss at the femoral neck was 1.5 ± 2.4% in females and 2.9 ± 2.0% in males with a significant decrease in BMD Z-score over time (<i>p</i>=0.005 and <i>p</i>=0.02 for females and males, respectively), indicating increased bone loss at this site. Hyperbilirubinaemia and low circulating levels of 25-hydroxy vitamin D<sub>3</sub> predicted increased bone loss at the femoral neck. These findings suggest that cortical bone, in addition to trabecular bone, may be affected in CLD and bilirubin and vitamin D<sub>3</sub> may be involved in the pathophysiology of osteoporosis in CLD. </p><p>In order to elucidate the suggested role of insulin-like growth factors (IGFs) and leptin in the pathophysiology of osteoporosis in CLD, we studied the relationship between these factors and BMD. Levels of IGFs were extremely low (<i>p</i><0.0001 compared with the controls) and related to liver function but no correlation was found between the IGFs and BMD. Serum leptin adjusted for BMI correlated negatively with BMD in female patients (<i>p</i>=0.003 and <i>p</i>=0.04 at the lumbar spine and the femoral neck, respectively) and in male patients at the femoral neck (<i>p</i>=0.04). Thus, the IGFs appear not to be involved in the pathophysiology of osteoporosis in CLD but a role of circulating leptin is possible. </p>
627

Osteoporosis in chronic liver disease

Ormarsdóttir, Sif January 2001 (has links)
Ormarsdóttir, S. 2001. Osteoporosis in Chronic Liver Disease. Acta Universitatis Upsaliensis. Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine 1037. 60 pp. Uppsala. ISBN 91-554-5021-0. Osteoporosis is a well-known and frequently reported complication of chronic liver disease (CLD) with a high fracture rate contributing to significant morbidity after liver transplantation. The pathogenesis is unknown and controversy exists about many risk factors for osteoporosis in CLD. In the present thesis, bone mineral density (BMD) was found to be significantly lower at the lumbar spine (p&lt;0.01) in a cohort of patients with CLD compared with age- and gender -matched individuals. Osteoporosis was found in 30% of the patients and 15% of the controls, respectively. Low body mass index (BMI), corticosteroid treatment, prothrombin time, age and female gender were independent risk factors for osteoporosis in the patients. In a follow-up study, 43 of 72 patients were available for a second BMD measurement 25 months (median) after the first. Bone loss at the femoral neck was 1.5 ± 2.4% in females and 2.9 ± 2.0% in males with a significant decrease in BMD Z-score over time (p=0.005 and p=0.02 for females and males, respectively), indicating increased bone loss at this site. Hyperbilirubinaemia and low circulating levels of 25-hydroxy vitamin D3 predicted increased bone loss at the femoral neck. These findings suggest that cortical bone, in addition to trabecular bone, may be affected in CLD and bilirubin and vitamin D3 may be involved in the pathophysiology of osteoporosis in CLD. In order to elucidate the suggested role of insulin-like growth factors (IGFs) and leptin in the pathophysiology of osteoporosis in CLD, we studied the relationship between these factors and BMD. Levels of IGFs were extremely low (p&lt;0.0001 compared with the controls) and related to liver function but no correlation was found between the IGFs and BMD. Serum leptin adjusted for BMI correlated negatively with BMD in female patients (p=0.003 and p=0.04 at the lumbar spine and the femoral neck, respectively) and in male patients at the femoral neck (p=0.04). Thus, the IGFs appear not to be involved in the pathophysiology of osteoporosis in CLD but a role of circulating leptin is possible.
628

Bone Metabolism in Men

Gillberg, Peter January 2001 (has links)
In this thesis, the importance of the growth hormone (GH)/insulin-like growth factor (IGF) system and sex steroids for male bone metabolism has been investigated, and the effects of continuous low dose GH replacement in GH deficient (GHD) adults. In a population-based sample of men, positive correlations were found between bone mineral density (BMD) and IGF-I, IGF-II, IGF binding protein (IGFBP)-3 and the testosterone/sex hormone binding globulin (SHBG) ratio. Serum IGFBP-3 and testosterone levels and weight accounted for 34% to 48% of the variation in BMD at different sites. Compared to healthy age matched controls, men with idiopathic osteoporosis had lower estradiol/SHBG ratio and higher SHBG levels. There were no differences between the groups in serum levels of IGF-I, IGFBP-3, 24 hour cumulated GH secretion or peak GH secretion. In the patients, there was a positive correlation between the estradiol/SHBG ratio and BMD in femoral neck. Treatment of patients and controls with GH 0.8 mg/day for one week resulted in similar increases in serum markers for bone turnover in both groups. Several positive correlations between indices of GH secretion and markers for bone turnover were found in the patients. Men with idiopathic osteoporosis were treated with GH, continuously (0.4 mg/day) or intermittently (0.8 mg/day for two weeks every third month), for two years followed by one year of follow-up. After two years, the BMD and bone mineral content in lumbar spine and total body and serum osteocalcin levels were increased in both groups. This increase was sustained one year post treatment. Treatment of GHD adults with a low fixed dose of GH (0.17 mg/day) for three months, resulted in increases in serum IGF-I and IGFBP-3 levels and lean body mass, and a reduction in fat mass and total and low-density lipoprotein cholesterol levels. These beneficial effects were accomplished without serious side effects. These findings indicate that: i) the sex hormone and GH/IGF systems are important in male bone metabolism, ii) a combination of subtle disturbances in these two systems could contribute to the development of male idiopathic osteoporosis, iii) GH treatment could be considered as a treatment option in this condition.
629

Development of a protein-free fed-batch process for NS0 cells: studies on regulation of proliferation

Spens, Erika January 2006 (has links)
The overall objective of this study was to investigate how NS0 cell proliferation is regulated in protein-free media. The hypothesis was that during the adaptation to growth factor-free media, animal cell lines start to produce their own autocrine growth factors to support proliferation, and after some time in a culture the effects of these factors are lost which results in cessation of proliferation. A chemically defined, protein-free and animal component-free medium was developed for the NS0 cells. This medium was comprised of a basal hybridoma medium to which phosphatidyl¬choline, cholesterol, β-cyclodextrin, ferric citrate and amino acids were added. A fed-batch process was then developed in this medium. The feed profile was optimised in a step-wise manner with a final feed solution containing glucose, glutamine, lipids, amino acids, vitamins, sodium selenite and ethanolamine. Specifically, supplementation with lipids (cholesterol) had a drastic effect on cell growth. Calcium, magnesium and potassium were not depleted during culture and a feed containing also iron, lithium, manganese, phosphorous and zinc did not significantly enhance the cell yield further. More than 8 x 106 viable cells mL-1 and 600 mg antibody L-1 was obtained in the final fed-batch. This corresponded to a 4.3-fold increase in viable cell yield and an 11.4-fold increase in product yield compared to bioreactor batch culture when the dilution of the fed-batch culture was also accounted for. The presence of autocrine growth factors in NS0 cell cultures was initially investigated by studying the effects of conditioned medium (CM). Concentrated CM had a significant positive effect on cell growth and part of this effect could be attributed to factor(s) eluting from a gel-filtration column at 20-25 kDa. In the search for cell-derived factors affecting cell growth the following proteins were identified as released/secreted by the NS0 cells; cyclophilin A, cyclophilin B, cystatin C, D-dopachrome tautomerase, IL-25, isopentenyl-diphosphate delta-isomerise, macrophage migration inhibitory factor (MIF), β2-microglobulin, niemann pick type C2, secretory leukocyte protease inhibitor (SLPI), thioredoxin-1, TNF-α, tumour protein translationally controlled-1 and ubiquitin. Zymogram electrophoresis further identified aspartic acid, papain-like cysteine (including cathepsin L) and serine protease activity in the CM. Pro/cathepsin L, CypB, EGF, IFN-α/β/γ, IGF-I/II, leukaemia inhibitory factor, IL-6, IL-11, IL-25, MIF, oncostatin M, TGF-β and TNF-α were excluded as involved in autocrine regulation of NS0 cell proliferation. The serine protease activity was suggested to affect the cells negatively and since the serine protease inhibitor SLPI is also present in NS0 CM, a balance in serine protease activity may be crucial for optimal cell growth. Further, the receptor gp130, known to be associated with myeloma cell growth, was shown to be essential for NS0 cell proliferation as demonstrated by siRNA gene silencing. The results suggested that autocrine regulation of proliferation in NS0 cell cultures involves the receptor subunit gp130. / QC 20100920
630

Critical Evaluation Of Endogenous Regional Development Theories

Cicek, Huseyin 01 February 2013 (has links) (PDF)
Regional development discourses and theories have significantly changed since the born of regional science. Focus of regional development theories has shifted from industrialization efforts via large-scale enterprises and transfer of central government funds to disadvantaged regions to endogenous capabilities and potentials of innovation and knowledge creation. Endogenous factors and self-development capabilities are highly emphasized by recent development literature. Changes in the regional development discourses also affected regional policies, policy tools and actors / endogenous factors and self-development discourses became dominant in regional development policies and implementations. However, source of regional development for less developed regions that do not have endogenous potentials and self-development capability have not clearly defined and have not empirically tested. The thesis attempted to empirically define regional growth factors and the usefulness of theoretical frameworks. In the thesis, econometric model of Turkey is used for the empirical study. The theoretical framework discussed in the thesis is both economic theories and regional development models. The study shows that all theoretical models offer only partial explanations of regional growth. While study shows that factors emphasized by traditional theories support regional growth, the study has no evidence supporting that soft factors emphasized by recent theories support regional growth. The main findings of this study contribute to theoretical and empirical field by reintroducing role of government and interventions. Factors highlighted by recent regional development theories are not sufficient for explaining growth, since the regional policies at the national level continue to be important therefore factors emphasized by traditional theories still have significant contributions to growth.

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