No description available.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 128-140).

Thesis (Ph.D. in Microbiology) -- University of Colorado at Denver and Health Sciences Center, 2005. / Typescript. Includes bibliographical references (leaves 201-223).

Cystinuria is defined as an inherited disorder characterized by increased urinary excretion of cystine and the dibasic amino acids arginine, lysine and ornithine. The only clinical manifestation of cystinuria is renal cystine stone formation due to the low solubility of cystine in the urine. Cystinuria can be attributed to mutations in the SLC3A1 and SLC7A9 genes in the majority of all cases and it has been a common expectation that molecular genetic studies of cystinuria would aid in understanding of the varying clinical outcome seen in the disease. Besides human, the disease has been most extensively studied in the domestic dog. The present study was undertaken to investigate the molecular genetic basis of cystinuria in patients from Sweden and to correlate genetic findings with phenotypes produced regarding cystine and dibasic amino acid excretion. Further, attempts were made to elucidate the molecular genetics of cystinuria in the dog. The entire coding sequences of the SLC3A1 and SLC7A9 genes were analysed by means of SSCA and DNA sequencing in 53 cystinuria patients and genetic findings were related to urinary excretion of cystine and dibasic amino acids in a subset of the patient group. We detected a total number of 22 different mutations in the SLC3A1 and SLC7A9 genes, 18 of which were described for the first time. We have found a probable genetic cause of cystinuria in approximately 74 % of our patients and a possible contribution to the disease in another 19 %. Mutations in the SLC3A1 gene is the major cause of cystinuria in our group, with only a minor contribution of SLC7A9 mutations. The group of patients presenting SLC3A1 mutations in a heterozygous state or lacking mutations in both genes had higher values of total urinary cystine and dibasic amino acids compared to patients homozygous for SLC3A1 mutations. The reason for this discrepancy remains unclear, but the possible impact of medical treatment with sulfhydryl compounds on total cystine values was ruled out. Sequencing of the full-length canine SLC7A9 cDNA was accomplished using the RACE technology and results from mutation analyses of SLC7A9 and SLC3A1 in cystinuric dogs showed that only two out of 13 dogs have mutations with possible impact on protein function in these genes. DNA sequencing was used for all exons of both genes in the dog, and in human cystinuria patients, all samples lacking mutations or showing heterozygosity after SSCA screening were sequenced in both genes as well. This implies that all point mutations present have been detected, but the possibility of mutations escaping PCR based methods as well as mutations in regulatory parts of the SLC3A1 and SLC7A9 genes remains in cases lacking a full molecular genetic explanation of the disease. Finally, clinical and genetic data from our study of cystinuria both in man and dog exemplifies that manifestation and clinical severity of cystinuria is not determined by genetic alterations in the SLC3A1 and SLC7A9 alone. Environmental factors, congenital malformations and modulating genetic factors are all possible contributors to the clinical outcome of cystinuria.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2007. / Härtill 4 uppsatser.

O metabolismo da glutamina (Gln) é alvo de atenções recentes para a compreensão da reprogramação metabólica para o suprimento energético das células tumorais em proliferação e para o desenvolvimento de novas estratégias terapêuticas em câncer. Tanto a absorção de glutamina quanto a taxa de glutaminólise, o catabolismo da Gln para gerar adenosina trifosfato (ATP) e lactato na mitocôndria estão aumentados em diferentes tumores. A Gln e glicose participam do processo da proliferação de células tumorais tanto na produção de (ATP) como no fornecimento de produtos intermediários utilizados na síntese de macromoléculas e Gln é utilizado para anaplerose do ciclo do ácido tricarboxílico. Nesse estudo, nosso objetivo foi analisar a expressão dos genes envolvidos na glutaminólise: ASCT2, LAT1, GLS, GLSISO1, GLSISO2, GLS2, GOT1, GOT2, GLUD1 e GPT2 em astrocitomas de diferentes graus de malignidade (AGI-AGIV), classificados de acordo com a Organização Mundial de Saúde (OMS), em relação às expressões em tecidos cerebrais não neoplásicos e correlacionar os níveis de expressão destes genes aos dados clínicos. PCR quantitativo em tempo real (qRT-PCR) foi realizado em 175 amostras, sendo 22 dentre estes de tecidos não neoplásicos. Observou-se tempo de sobrevida menor entre os pacientes com hiperexpressão de LAT1, na presença de hipoexpressão de ASCT2. A expressão de GLS foi comparativamente maior que a expressão de GLS2 entre os astrocitomas de diferentes graus de malignidade, corroborando descrições prévias de que GLS relaciona-se à proliferação tumoral e GLS2 à supressão do crescimento tumoral. Observou-se, adicionalmente, o aumento da associação das expressões destes genes conforme o aumento do grau de malignidade, culminando em GBM, onde estas correlações foram estatisticamente significativas. Apesar da demonstração da ativação gradativa desta via da glutaminólise com o aumento da malignidade, a hiperexpressão dos genes relacionados a esta via mostrou-se hiperexpressa em apenas um subgrupo de pacientes com GBM. Esta observação ressalta a heterogeneidade observada em GBM e a elegibilidade restrita deste subgrupo a eventuais estratégias terapêuticas que forem desenvolvidas com alvos nesta via / The metabolism of glutamine (Gln) is the target of recent attentions to understand the metabolic reprogramming of cancer cell for the energetic needs for cell proliferation, and to develop new cancer therapeutic strategies. Glutamine absortion and glutamine conversion to ATP and lactate in the mitochondria through glutaminolysis are both increased in different cancer types. Gln and glucose participate in metabolic pathways which provide ATP and intermediate substrats for synthesis of macromolecules, and Gln is used for anaplesoris of tricyclic acid cycle. The aims of the present study were to analyze the differential mRNA expressions of genes involved in the glutaminolysis pathways: ASCT2, LAT1, GLS, GLSISO1, GLSISO2, GLS2, GOT1, GOT2, GLUD1 e GPT2 in astrocytomas of different grades of malignancy (WHO grades I to IV) compared to non-neoplastic brain tissues, and to correlate these expression data to clinical outcome. Shorter overall survival time was observed among a subset of GBM patients presenting hyperexpression of LAT1 while ASCT2 was hypoexpressed. GLS expression was comparatively higher than GLS2 expression among astrocytomas of different grades of malignancy, which corrobates previous reports relating GLS to tumor proliferation and GLS2 to suppression of tumor growth. Additionally, increased gene expression correlation was observed in parallel to the increase of malignancy, and these associated expressions were significant among GBM. Although a stepwise increase of the glutaminolysis pathway was demonstrated with the increase of malignancy in astrocytomas, the hyperexpression of genes involved in this pathway were detected only in a subset of GBM patients. This finding confirm the heterogeneity observed among GBM, and highlights the fact that any therapeutic strategy aiming this pathway will be restricted to a subset of GBM patients

O metabolismo da glutamina (Gln) é alvo de atenções recentes para a compreensão da reprogramação metabólica para o suprimento energético das células tumorais em proliferação e para o desenvolvimento de novas estratégias terapêuticas em câncer. Tanto a absorção de glutamina quanto a taxa de glutaminólise, o catabolismo da Gln para gerar adenosina trifosfato (ATP) e lactato na mitocôndria estão aumentados em diferentes tumores. A Gln e glicose participam do processo da proliferação de células tumorais tanto na produção de (ATP) como no fornecimento de produtos intermediários utilizados na síntese de macromoléculas e Gln é utilizado para anaplerose do ciclo do ácido tricarboxílico. Nesse estudo, nosso objetivo foi analisar a expressão dos genes envolvidos na glutaminólise: ASCT2, LAT1, GLS, GLSISO1, GLSISO2, GLS2, GOT1, GOT2, GLUD1 e GPT2 em astrocitomas de diferentes graus de malignidade (AGI-AGIV), classificados de acordo com a Organização Mundial de Saúde (OMS), em relação às expressões em tecidos cerebrais não neoplásicos e correlacionar os níveis de expressão destes genes aos dados clínicos. PCR quantitativo em tempo real (qRT-PCR) foi realizado em 175 amostras, sendo 22 dentre estes de tecidos não neoplásicos. Observou-se tempo de sobrevida menor entre os pacientes com hiperexpressão de LAT1, na presença de hipoexpressão de ASCT2. A expressão de GLS foi comparativamente maior que a expressão de GLS2 entre os astrocitomas de diferentes graus de malignidade, corroborando descrições prévias de que GLS relaciona-se à proliferação tumoral e GLS2 à supressão do crescimento tumoral. Observou-se, adicionalmente, o aumento da associação das expressões destes genes conforme o aumento do grau de malignidade, culminando em GBM, onde estas correlações foram estatisticamente significativas. Apesar da demonstração da ativação gradativa desta via da glutaminólise com o aumento da malignidade, a hiperexpressão dos genes relacionados a esta via mostrou-se hiperexpressa em apenas um subgrupo de pacientes com GBM. Esta observação ressalta a heterogeneidade observada em GBM e a elegibilidade restrita deste subgrupo a eventuais estratégias terapêuticas que forem desenvolvidas com alvos nesta via / The metabolism of glutamine (Gln) is the target of recent attentions to understand the metabolic reprogramming of cancer cell for the energetic needs for cell proliferation, and to develop new cancer therapeutic strategies. Glutamine absortion and glutamine conversion to ATP and lactate in the mitochondria through glutaminolysis are both increased in different cancer types. Gln and glucose participate in metabolic pathways which provide ATP and intermediate substrats for synthesis of macromolecules, and Gln is used for anaplesoris of tricyclic acid cycle. The aims of the present study were to analyze the differential mRNA expressions of genes involved in the glutaminolysis pathways: ASCT2, LAT1, GLS, GLSISO1, GLSISO2, GLS2, GOT1, GOT2, GLUD1 e GPT2 in astrocytomas of different grades of malignancy (WHO grades I to IV) compared to non-neoplastic brain tissues, and to correlate these expression data to clinical outcome. Shorter overall survival time was observed among a subset of GBM patients presenting hyperexpression of LAT1 while ASCT2 was hypoexpressed. GLS expression was comparatively higher than GLS2 expression among astrocytomas of different grades of malignancy, which corrobates previous reports relating GLS to tumor proliferation and GLS2 to suppression of tumor growth. Additionally, increased gene expression correlation was observed in parallel to the increase of malignancy, and these associated expressions were significant among GBM. Although a stepwise increase of the glutaminolysis pathway was demonstrated with the increase of malignancy in astrocytomas, the hyperexpression of genes involved in this pathway were detected only in a subset of GBM patients. This finding confirm the heterogeneity observed among GBM, and highlights the fact that any therapeutic strategy aiming this pathway will be restricted to a subset of GBM patients