Tesi: "GST" – Grafiati

1

Atar, Murat [Verfasser]. "Synthese und photophysikalische Untersuchung von phthalimidbasierten modularen Fluoreszenzsonden zur Detektion von ROS, GSH/GST und Cyanid / Murat Atar". München : Verlag Dr. Hut, 2018. http://d-nb.info/1161250433/34.

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Irtem, Kartal Deniz. "The Expression Of Gst Genes In Diabetic Rat Liver Tissues". Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610081/index.pdf.

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Free radicals which have critical roles in living systems through their beneficial and detrimental effects play an important role in medical revolution in health. Radicals are produced in the cells and tissues of our bodies by various processes and reactions. Diabetes mellitus is an extremely common disease in the world which seems to be accompanied by a shortage of antioxidants and an increase in free radicals, the end result of oxidative stress. Glutathione S-Transferases (GST
EC 2.5.1.18) are found in enzymatic defense system which has a role in defending cells against potentially toxic and/or carcinogenic compounds. In this study, the changes in the activities and expressions of various GST isozymes in the liver of diabetic rats related to oxidative stress were studied. The effects of antioxidants, Vitamin C and &
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-Lipoic acid on GST isozyme activities and mRNA expressions were also investigated. According to our results, diabetic rats exhibited decreased mRNA expressions of both GSTA2 and GSTM1 genes, but the activities of only GST Mu isozyme decreased in diabetic rats, compared to controls and GST Alpha isozyme activity remained unchanged in diabetic animals. Our results also showed that &
#945
-Lipoic acid individually has no significant effect on both GSTA2 and GSTM1 gene expressions and activities. Furthermore, although the administration of Vitamin C alone showed no significant effect on all GST isozyme activities, it decreased GSTA2 mRNA expression significantly. The administration of Vitamin C and &
#945
-Lipoic acid together affected both GSTA2 and GSTM1 mRNA expressions in control rats, but only GST Mu activity showed a significant change. The results of this study showed that, the administration of two antioxidants, &
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-Lipoic acid and Vitamin C alone and together did not reverse the results of diabetes at the level of both gene expression and activities of GST isozymes.

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3

Salmonowicz, Daniel J. "Creation of a Unique GST-FAK Plasmid for Protein Expression". Ohio Dominican University Honors Theses / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=oduhonors1588678705964411.

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4

Utiumi, Kiyoko Uemura. "Avaliação da resposta imune humoral em camundongos para a proteína glutationa s-transferase de Rhipicephalus (Boophilus) microplus (GST-Bm), e de haemaphysalis longicornis (GST-HI)". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/12432.

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O carrapato Rhipicephalus (Boophilus) microplus é um ectoparasito hematófago que infesta os rebanhos bovinos de regiões tropicais e subtropicais, e é um dos principais causadores de prejuízos econômicos à pecuária. O principal método de controle baseia-se no uso de acaricidas. No entanto, devido à crescente preocupação com os problemas criados pela poluição química do meio ambiente, ao alto custo e toxicidade das drogas e ao aparecimento de carrapatos resistentes aos acaricidas, métodos alternativos para o controle do R. microplus devem ser encontrados. Um dos métodos alternativos estudados é o uso de vacinas. As glutationa S-transferases (GST) são enzimas que estão presentes em organismos animais e vegetais e entre suas funções podem-se destacar transporte intracelular, participação em processos digestivos, síntese de prostaglandinas, e detoxificação de substâncias tóxicas e proteção contra estresse oxidativo. Neste estudo foi analisada a resposta imunológica comparativa de camundongos para a GST de R. microplus (GST-Bm) e para a GST de Haemaphysalis longicornis (GST-Hl). Ambas as proteínas foram expressas em Escherichia coli linhagem AD494, e purificadas por cromatografia de afinidade por glutationa utilizando a coluna GSTrap FF. Para verificar a imunogenicidade das proteínas, foram utilizados 25 camundongos Balb/c divididos em 12 grupos. As condições testadas foram as inoculações das proteínas GST-Bm e GST-Hl com os adjuvantes Montanide, saponina ou sem adjuvantes. Camundongos controle foram inoculados com extrato de E. coli ou somente com os adjuvantes. Foi coletado sangue de todos os animais com intervalos de sete dias durante 70 dias. Os soros foram analisados por ELISA para acompanhar a cinética da produção de anticorpos de todos os animais imunizados. Os camundongos inoculados com GST-Hl emulsificada com Montanide mostraram aumento dos níveis de anticorpos a partir do dia 21. O nível máximo de anticorpos foi detectado no dia 42, e diminuiu após o dia 56. Todos os outros animais não apresentaram aumento nos níveis de anticorpos.
Rhipicephalus (Boophilus) microplus tick is a hematophagous ectoparasite that infests cattle in tropical and subtropical regions and is one of the principal causes of economic losses in the cattle farm. The principal method of control is the use of acaricides. However, due to increased worry about environmental chemical pollution, high costs and drugs toxicity and the selection of ticks resistant to acaricides, alternative methods for R. microplus control should be developed. One of these methods is vaccination. Glutathione S-transferases (GSTs) enzymes are present in animal and vegetal organisms and the functions are intracellular transport, participation in digestive process, synthesis of prostaglandins and detoxification of toxic substances and protection against oxidative stress. In this study the immunological response of mice inoculated with R. microplus GST (GST-Bm) and with Haemaphysalis longicornis GST (GST-Hl) was analysed. Both proteins were expressed in Escherichia coli strain AD494 and were purified by affinity chromatography using GSTrap FF columm. To verify the protein immunogenicity, 25 Balb/c mice divided into 12 groups were used. The tested conditions were inoculation of GST-Bm, GST-Hl proteins with Montanide and saponin adjuvants or without adjuvant. Control mice were inoculated with E. coli extract or the adjuvant alone. Blood from all animals were collected with intervals of seven days during seventy days, the sera were analyzed by ELISA to verify the kinetic of antibodies production of all immunized animals. Mice inoculated with GST-Hl emulsified with Montanide showed an increase in the antibodies levels from day 21. The maximum level of antibodies was detected on day 42 and decreased after day 56. The other animals did not show an increase in antibodies levels.

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Ribeiro, Junior Anicezio de Paula. "ANÁLISE DOS POLIMORFISMOS DO GENE GSTM1 EM AMOSTRAS DE PTERÍGIO EM GOIÂNIA-GOIÁS". Pontifícia Universidade Católica de Goiás, 2014. http://localhost:8080/tede/handle/tede/2378.

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The first reports about pterygium date back to Hippocrates. This disease still hides mysteries about its pathogenesis in a way that even today it threaten vision health of many people around the world. It is a formation of fibrous tissue that grows excessively and with an abnormal shape on the cornea The anomaly consists of epithelial and subepithelial tissue and it is highly vascularized. A large number of factors are associated with the pathogenesis of pterygium such as physical factors: heat, dust and other particles in the atmosphere; and biological factors such as immunological mechanisms, mechanisms that involve the reorganization of the extracellular matrix, growth factors, cytokines, apoptosis, and angiogenic factors. The pterygium affects individuals who mainly inhabit tropical countries located near the equator and who working out in the sun; thus, the incidence is higher in the region between 40 degrees latitude north and south of the Equator. Considering the need to further investigate the association between GSTM1 polymorphisms and the formation of pterygium, this paper aims to analyze this relationship. The analysis of the null polymorphism of the GSTM1 gene for the case group found a significant difference between the GSTM1 null genotype in case and control groups. The null genotype of the GSTM1 gene is statistically significant in males, but not in female. The null genotype of the GSTM1 gene is statistically significant in Caucasians, but not in Brown or Black. The GSTM1 null genotype is not related to the risk factors analyzed: cases in family, occupational exposure, smoking, hypertension and diabetes.
Os primeiros relatos sobre pterígio datam da época de Hipócrates, mesmo assim essa condição ainda esconde mistérios sobre sua patogenia de forma tal que ainda nos dias de hoje pode ameaçar a saúde da visão de inúmeras pessoas. É uma formação fibrosa de conjuntiva cresce exageradamente e de forma anormal sobre a córnea, sendo composta por tecido epitelial e subepitelial, e altamente vascularizada. Um grande número de fatores está relacionado com a patogenia do pterígio tais como, aspectos físicos, calor, poeira e outras partículas presentes na atmosfera; e fatores biológicos como certos mecanismos imunológicos, mecanismos que envolvem a reorganização da matriz celular, fatores de crescimento, citocinas, apoptose e fatores angiogênicos. O pterígio acomete indivíduos que habitam principalmente países de clima tropical, localizados próximo à linha do Equador e que trabalham expostos ao sol; assim, a incidência é maior na região entre 40 graus de latitude ao norte e ao sul do Equador. Considerando a necessidade de investigar melhor a associação entre os polimorfismos do GSTM1 e a formação do pterígio, o presente trabalho tem o objetivo analisar essa relação. A análise do polimorfismo do gene GSTM1 para o grupo caso constatou que há diferença significativa entre o genótipo nulo do gene GSTM1 nos grupos caso e controle. O genótipo nulo do gene GSTM1 é estatisticamente significante na população masculina, mas não na feminina. O genótipo nulo do gene GSTM1 é estatisticamente significante na etnia branca, mas não na parda ou negra. O genótipo nulo do gene GSTM1 não está relacionado aos fatores de risco analisados: casos na família, exposição ocupacional, fumo, hipertensão e diabetes.

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6

Sheppard, Hilary Morna. "Characterisation of cis-elements in the GST-27 promoter of Zea mays". Thesis, University of Leicester, 1996. http://hdl.handle.net/2381/35150.

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The ability to control the expression of selected genes has many applications both in industry and academic research. The 27 kDa subunit of the glutathione S-transferase II (GST-27) gene in maize is not transcribed in the aerial organs of maize during normal growth and development. However, it can be induced by treatment with herbicide safeners (e.g. dichlormid) resulting in high levels of expression. Since the promoter of this gene may be useful as a tool to control the expression of other genes, we have investigated the molecular basis of its induction by the identification of the cis-acting promoter elements involved. Safeners also induce the production of enzymes and substrates which are involved in a plant's defense against pathogen attack and in combating oxidative stress. Thus, information relating to GST-27 induction may also add to our knowledge relating to these other responses. Deletion analysis of the GST-27 promoter was carried out by transient expression of GST- 27::GUS transcriptional fusions in Black Mexican Sweet (BMS) maize cells. These experiments indicated that a 378 base pair region of the promoter can confer safener-inducibility on GUS expression. This region of the promoter was in vivo footprinted and four putative safener-responsive elements were thus identified (regions in which G residues are protected when the gene is expressed). These elements are similar to each other and to an ethylene responsive element in the GST1 gene of carnation. Electrophoresis mobility-shift assays indicated that one or more nuclear proteins from maize leaves specifically interact with all of the elements. These elements were mutated in GST-27::GUS constructs, which were tested in transient assays in BMS cells in order to obtain direct evidence for their involvement in safener-dependent transcription. The transient assay technique was, however, found to be insufficiently sensitive for this purpose. The GST-27::GUS constructs containing mutations of the putative elements were therefore tested in transgenic tobacco. The 570 base pairs of the wild type GST-27 promoter upstream of the transcription start point was found to retain inducibility in transgenic tobacco plants, but a 378 base pair GST-27::GUS transcriptional fusion (which was inducible in BMS maize cell lines) was not inducible when tested in tobacco. In order to test for loss of function, mutations of the putative safener-responsive elements were introduced into the 378 base pair truncated promoter; in order to test for a gain of function the putative elements were fused to the -60 and -90 35S cauliflower mosaic virus minimal promoters and tested in stable tobacco transformants. These experiments did not, however, prove that these elements play a role in safener-dependent transcription. Surprisingly, the -90 minimal promoter itself was found to be responsive to safener. A previously characterised cis-element, activation sequence-1 (as-1), is contained within the -90 minimal promoter and may account for its inducibility; a similar element is present in the GST-27 promoter but its role in safener-dependent transcription, if any, is unclear.

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NASCIMENTO, Luiz Eduardo Alves Bezerra do. "Efeitos letais e subletais do fenantreno e pireno em recém-nascidos do peixe Poecilia vivipara". Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/17375.

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Poecilia vivipara apresenta distribuição ampla na costa brasileira, e sua reprodução por viviparidade viabiliza a utilização de jovens recém-nascidos com 24 horas de vida em estudos ecotoxicológicos para avaliar o potencial de toxicidade de contaminantes ambientais. Este trabalho teve por objetivos avaliar os efeitos letais e subletais nestes estágios iniciais de vida do peixe estuarino Poecilia vivipara após exposição a diferentes concentrações dos HPAs fenantreno e pireno dissolvidos na água. Os jovens recém-nascidos foram obtidos de plantel de reprodutores mantidos em laboratório, expostos ao fenantreno nas concentrações 0, 10, 50, 200 e 500 μg L-1 durante 7 dias, e ao pireno nas concentrações 0, 1, 10, 50 e 100 μg L-1 durante 14 dias. Após a exposição foi avaliada a taxa de mortalidade, e nos sobreviventes foram quantificados os parâmetros subletais atividade da Glutationa S-Transferase (GST), velocidade de natação espontânea, captura de presas e crescimento. Jovens expostos a 500 μg fenantreno L-1 apresentaram 40% de mortalidade, e não foi detectada mortalidade nas demais concentrações. Jovens expostos ao pireno nas concentrações 50 e 100 μg L-1 apresentaram 44% e 33% de mortalidade, respectivamente, e não foi detectada mortalidade nas demais concentrações. Com relação aos parâmetros subletais, a concentração de efeito observado (CEO) para atividade de GST, velocidade média de natação, distância linear nadada e incremento de peso foi igual a 500 μg fenantreno L-1. Já para a exposição ao pireno a (CEO) para atividade de GST foi igual a 10 μg pireno L-1, 50 μg pireno L-1 para velocidade média de natação e distância linear nadada, e 1 μg pireno L-1 para incremento de peso. O aumento da atividade da GST após exposição a 500 μg fenantreno L-1 sugere um aumento dos gastos energéticos com os processos de biotransformação de fase 2, e esta alteração esteve associada a decréscimos na atividade locomotora, na habilidade de capturar presas, e também no crescimento. A exposição ao pireno também apresentou um padrão semelhante, com alterações detectadas em concentrações menores, indicando uma maior potência do pireno comparado ao fenantreno para induzir a GST, gerar hipoatividade locomotora e inibir o crescimento, parâmetro de maior relevância para o recrutamento da espécie. Estes resultados sugerem que o uso de jovens recém-nascidos de Poecilia vivipara como modelos ecotoxicológicos para a compreensão dos efeitos de contaminantes em parâmetros de diferentes níveis de organização biológica relacionados ao recrutamento de peixes é promissor.
Poecilia vivipara has a wide distribution pattern along the Brazilian coast, and its reproduction by viviparity enables the use of newborn in ecotoxicological studies to evaluate the potential toxicity of environmental contaminants. This study aimed to assess the lethal and sublethal effects on these early stages of life of the estuarine fish Poecilia vivipara after exposure to different concentrations of the PAHs phenanthrene and pyrene dissolved in water. The newborn were obtained from a breeding stock kept under controlled conditions, and exposed to phenanthrene concentrations of 10, 50, 200 and 500 μg L-1 and control for 7 days, and pyrene concentrations of 1, 10, 50 and 100 μg L-1 and control for 14 days. After exposure, the mortality rate was calculated, and the survivors were evaluated for the sublethal parameters glutathione S-transferase activity (GST), spontaneous swimming speed, prey capture rate and growth. Young individuals exposed to 500 μg phenanthrene L-1 exhibited 40% mortality, only detected in this concentration. Juveniles exposed to pyrene concentrations of 50 and 100 μg pyrene L-1 exhibited 44% and 33% mortality, respectively, and no mortality was detected in other tested concentrations. Regarding sublethal parameters, the lowest observed effect concentration (LOEC) for GST activity, average swimming speed, linear swimming distance and weight increase was equal to 500 μg phenanthrene L-1. Already for an exposition to pyrene the LOEC for GST activity was equal to 10 μg pyrene L-1, 50 μg pyrene L-1 for average swimming speed, and 1 μg pyrene L-1 for weight increase. The increase in GST activity after exposure to 500 μg phenanthrene L-1 suggests an increase in energy expenditure with the biotransformation processes of phase 2, and this change was associated with decreases in locomotor activity, the ability to catch prey, and also in growth. Exposure to pyrene also exhibited a similar pattern, with changes detected in lower concentrations, indicating a greater pyrene potency compared to phenanthrene to induce GST and to generate locomotor hypoactivity and inhibit growth, the most relevant parameter for the recruitment of the species. These results suggest the potential use of newborn young Poecilia vivipara as ecotoxicological models for understanding the effects of contaminants on parameters of distintic biological organization levels related to the recruitment of fish.

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Bloomer, Daniel John. "Sediment sorting in the gravel-sand transition along rivers : a field and modelling investigation". Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341852.

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9

Beasley, Steven Ari. "Expression of the Pasteurella haemolytica O-sialoglycoprotein endopeptidase as a GST fusion protein". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ33205.pdf.

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Santos, Stéphanie Piacenti dos. "Marcadores moleculares GST e CYP relacionados com fatores clínicos em câncer de mama". Faculdade de Medicina de São José do Rio Preto, 2016. http://hdl.handle.net/tede/420.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Breast cancer is a leading cause of death in women worldwide. The etiology of this disease is multifactorial, including factors such as habits and lifestyle, hormonal, environmental and genetic. The xenobiotic metabolism contribute to the development of breast carcinoma and polymorphisms in genes encoding enzymes in this pathway, such as GST (GSTM1 and GSTT1) and CYPs (CYP1A1*2A and CYP1A1*2C) have been associated to breast cancer. Objectives: To investigate the influence of the GSTM1, GSTT1, CYP1A1*2A and CYP1A1*2C polymorphisms at the risk for developing breast cancer; to evaluate the association of polymorphisms and risk factors (age, smoking, alcohol, clinical features), tumor clinical and histopathologic features in breast cancer. Methods: This case-control study included 752 women, 219 patients and 533 controls. Molecular analysis were performed by PCR-multiplex (GSTM1 null and GSTT1 null), PCR-RFLP (CYP1A1*2A) and real-time PCR (CYP1A1*2C). For the statistical analysis, the MINITAB 16.0 (Multiple Logistic Regression Test), SNPstats (Inheritance Model tests) and BioEstat 5.0 (Hardy-Weinberg test) tests were used. Results: Women with old age and the alcohol consumption had increased risk for developing breast cancer. Women with breast cancer had slightly higher frequency (51%) of the GSTM1 null genotype than women without cancer (49%), however this difference was not significant statistically. GSTT1 null genotype was also not associated with breast cancer. CYP1A1*2A polymorphism was associated with the risk for breast cancer and CYP1A1*2C polymorphism was more frequent in tumors with no distant metastases. Conclusions: Women with age advanced and who drink alcohol present increased risk for developing breast cancer. CYP1A1*2A polymorphism is associated with breast cancer and CYP1A1*2C polymorphism is related to women with no distant metastases. The polymorphisms of the GSTM1 and GSTT1 genes are not associated with the development of breast cancer.
O câncer de mama é uma das principais causas de morte em mulheres no mundo. A etiologia desta doença é multifatorial e inclui fatores como hábitos, estilo de vida, hormonais, ambientais e genéticos. O metabolismo de xenobióticos contribui para o desenvolvimento do carcinoma mamário, e polimorfismos nos genes que codificam enzimas desta via, tais como GSTs (GSTM1 e GSTT1) e CYPs (CYP1A1*2A e CYP1A1*2C) têm sido associados ao câncer de mama. Objetivos: Investigar a influência dos polimorfismos GSTM1, GSTT1, CYP1A1*2A e CYP1A1*2C no risco de desenvolvimento de câncer de mama; avaliar a associação dos polimorfismos e fatores de risco (idade, fumo, álcool, características clínicas) no câncer de mama, assim como características clínicas e histopatológicas do tumor. Casuística e Métodos: O presente estudo caso-controle incluiu 752 mulheres, 219 pacientes e 533 controles. Para análise molecular foram realizadas as técnicas de PCR-Multiplex (GSTM1 e GSTT1), PCR-RFLP (CYP1A1*2A) e PCR em tempo real (CYP1A1*2C). Para a análise estatística foram utilizados os programas MINITAB 16.0 (teste de Regressão Logística Múltipla), SNPstats (testes de Modelos de Herança) e BioEstat 5.0 (teste de Equílibrio de Hardy-Weinberg). Resultados: Mulheres com idade avançada e com o hábito etilista apresentaram risco aumentado para o desenvolvimento de câncer de mama. Mulheres com carcinoma mamário apresentaram frequência discretamente maior (51%) do genótipo nulo GSTM1 em relação a mulheres sem câncer (49%), no entanto essa diferença não foi estatisticamente significante. O genótipo nulo de GSTT1 também não foi associado ao câncer de mama. O polimorfismo CYP1A1*2A foi associado ao risco para câncer de mama e o polimorfismo CYP1A1*2C foi mais frequente em tumores com ausência de metástase à distância. Conclusões: Mulheres com idade avançada e que ingerem bebida alcoólica apresentam risco aumentado para desenvolver câncer de mama. O polimorfismo CYP1A1*2A está associado ao câncer de mama e o polimorfismo CYP1A1*2C está relacionado às mulheres com ausência de metástase à distância. Os polimorfismos dos genes GSTM1 e GSTT1 não apresentam associação com o desenvolvimento do câncer de mama.

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McHugh, Thomas Erik. "Metabolism of aflatoxin epoxide by glutathione S-transferase : new insights into GST function /". Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/8446.

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12

SILVA, Juliana Scanoni. "HPAs biliares e biomarcadores bioquímicos na carapeba Eugerres brasilianus em quatro estuários tropicais do Nordeste brasileiro". Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/16475.

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Hidrocarbonetos policíclicos aromáticos (HPAs) são compostos derivados de petróleo conhecidos por seu potencial de toxicidade a organismos aquáticos. Regiões estuarinas são frequentemente contaminadas por HPAs em decorrência de processos de urbanização e atividades industriais, incluindo a cadeia produtiva do petróleo. O trabalho teve o objetivo de avaliar a bioconcentração e efeitos bioquímicos de HPAs em Eugerres brasilianus coletados em quatro estuários no litoral sul de Pernambuco, a fim de obter um diagnóstico da poluição por estes contaminantes nestas regiões. As coletas foram realizadas no rio Ariquindá, sistema estuarino do rio Formoso (AR-SERF), no rio Massangana, no complexo estuarino de Suape (MA-CES), no sistema estuarino de Barra de Jangada (SEBJ), e no complexo estuarino da bacia do Pina (CEBP). A bile dos peixes foi analisada por Fluorescência Fixa para estimar a concentração em equivalentes dos HPAs naftaleno, fenantreno e criseno. Amostras de fígado foram utilizadas para análise de biomarcadores enzimáticos de fase I (etoxiresorufina orto-deetilase, EROD), fase II (glutationa S-transferase, GST), e defesa antioxidante (catalase, CAT, e glutationa redutase, GR). A análise de HPAs na bile e atividades enzimáticas em peixes coletados num ciclo anual em MA-CES e AR-SERF indicou uma semelhança na contaminação por HPAs na bile e nos níveis de atividades enzimáticas dos biomarcadores avaliados entre estes estuários, apesar da diferença do padrão de atividades antrópicas destas regiões. O CES comporta um complexo portuário com alta atividade industrial enquanto o SERF possui baixa densidade populacional e atividades turísticas. Os peixes coletados em SEBJ e CEBP apresentaram bile com concentrações do HPA criseno entre 13 x e 19 x maiores que AR-SERF, respectivamente. Foi detectado aumento das atividades da EROD, GST e CAT das regiões do SEBJ e CEBP, chegando a 30 x para a EROD, e aproximadamente 2 x para GST e CAT em comparação com AR-SERF. A maior bioconcentração de HPAs na bile e maior indução enzimática nos peixes E. brasilianus do SEBJ e CEBP indicam que estes estão dispendendo energia para tentar se adaptar a esta contaminação, o que pode ter consequências para o seu crescimento e sobrevivência nestas regiões. Os resultados indicam que SEBJ e CEBP recebem um maior aporte de HPAs, associado a maior densidade populacional e atividades antrópicas nas bacias desses rios. Os parâmetros utilizados serão úteis para o monitoramento destes sistemas estuarinos, em especial do CES, em franco processo de urbanização e industrialização.
Polycyclic aromatic hydrocarbons (PAHs) are oil derived compounds known for their toxicity potential towards aquatic organisms. Estuarine regions are frequently contaminated with PAHs as a result of urbanization processes and industrial activities, including the oil productive chain. The work aimed to evaluate the bioconcentration and the biochemical effects of PAHs in Eugerres brasilianus sampled from four estuaries in the south coast of Pernambuco, in order to obtain a pollution diagnosis by these contaminants in such regions. The data collection was made in the Aquirindá river, Rio Formoso estuarine system (AR-RFES), in the Massangana river, in the Suape’s estuarine complex (MA-SEC), in the Barra de Jangada estuarine system (BJES) and in the Bacia do Pina estuarine complex (BPEC). The fish’s bile were analyzed using fixed fluorescence to estimate the equivalent concentrations of the PAHs naphthalene, phenanthrene and chrysene. Liver samples were used for phase 1 enzymatic biomarkers analysis (Ethoxyresorufin-O-deethylase, EROD), phase II (glutathione S-transferase, GST) and antioxidant defense (catalase, CAT, and glutathione reductase, GR). The analyzes of PAHs in bile and enzymatic activity in fish that were sampled in an annual cycle in MA-SEC and AR-RFES indicated a similarity between PAHs contamination in bile and the enzymatic activity levels of the biomarkers evaluated among these estuaries, despite the different anthropogenic activity patterns. The SEC comprises a port complex with high industrial activity, while the RFES has low population density and touristic activities. The bile of the fish sampled in BJES and BPEC showed chrysene concentration between 13 x and 19 x higher than AR-RFEC, respectively. An increase in EROD, GST and CAT activities was detected in the regions of BJES and BPEC, reaching 30 x for EROD, and approximately 2 x for GST and CAT. The high PAHs bioconcentration in the bile and the high enzymatic induction in E. brasilianus fish from BJES and BPEC indicate that these fish are wasting energy to try to become adapted to this contamination, which may have consequences to their growth and survival in such regions. The results indicate that BJES and BPEC receive a greater input of PAHs, associated with the higher population density and anthropogenic activities in these rivers’ basins. The parameters used will be useful for the monitoring of these estuarine systems, especially in SEC, which suffers with a rapid urbanization and industrialization process.

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13

Harbottle, Andrew. "Assessment of the relative contribution of metabolism and transport to cellular protection from the xenobiotics doxorubicin and benzo[a]pyrene". Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327204.

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14

Bisset, Louise Clair. "Fluorescence of a DNA-binding protein". Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320129.

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15

Thompson, Andrew D. "Design and Implementation of an Embedded H.264 Color Video Encoding Pipeline for a Mobile Processing Platform". University of Dayton / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1462221103.

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16

Kano, Mayuko, Yasuyuki Goto, Yoshiko Atsuta, Mariko Naito e Nobuyuki Hamajima. "Smoking Cessation After Genotype Notification: Pilot Studies of Smokers Employed by a Municipal Government and Those on Nagoya University Medical Campus". Nagoya University School of Medicine, 2007. http://hdl.handle.net/2237/9191.

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17

DAWOOD, KUTAYBA F. "New physiological roles of glautathione transferases". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/923.

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Glutathione transferases (GSTs) are enzymes able to conjugate GSH to a lot of toxic compounds thereby favoring their excretion. Recently, other protective roles of these enzymes have been discovered. In particular, it has been observed that a peculiar and strong interaction exists between some mammalian GSTs and an endogenous carrier of nitric oxide, the dinitrosyl-diglutathionyl iron complex (DNDGIC). This iron complex is a paramagnetic molecule with a characteristic EPR spectrum centered at g = 2.03, that is spontaneously formed when NO enters the cell. This complex is a strong irreversible inhibitor of glutathione reductase. The present work explores the possible role of GSTs like a protection system against DNDGIC. Actually, mammalian GSTs bind DNDGIC with extraordinary affinity (KD = 10-9-10-10 M). When rat hepatocytes are incubated in the presence of GSNO, a natural source of NO, a rapid formation of 0.1 - 0.2 mM intracellular DNDGIC has been observed. This concentration would be lethal for glutathione reductase. However the complex does not appear like a free species but completely bound to GSTs, that are present at the cytosolic level of 0.8 mM. In this form the complex is completely harmless for glutathione reductase. Surprisingly, electron paramagnetic data, reveal that DNGIC-GST is partially associated to subcellular fractions and in particular to nuclei. Our data indicate that about 10% of the cytosolic pool GST is electrostatically associated with the outer nuclear membrane, and a similar quantity is compartmentalized inside the nucleus. Mainly Alpha class GSTs, in particular GSTA1-1, GSTA2-2 and GSTA3-3, are involved in this double modality of interaction. Confocal microscopy and immunofluorescence experiments have been used to detail the electrostatic association in hepatocytes. A quantitative analysis of the membrane-bound Alpha GSTs suggests the existence of a multilayer assembly of these enzymes at the outer nuclear envelope that could represent a potent protection shell for the nucleus and an amazing novelty in cell physiology. A second target of this study is represented by the particular GST isoenzyme expressed by the Plasmodium falciparum (PfGST), the parasite causative of malaria. This enzyme is characterized by a peculiar dimer/tetramer transition that occurs in the absence of GSH and that causes a total loss of its enzymatic activity. Moreover PfGST binds hemin with high affinity and this interaction is finalized to the protection of the parasite against this toxic compound. Binding of hemin is regulated by a cooperative mechanism and does not occur in the tetrameric enzyme. Side directed mutagenesis, steady-state kinetic experiments, fluorescence anisotropy and X-ray crystallography were used to verify the involvement of some protein segment in the tetramerization process and in the cooperative phenomenon. Actually the loop 113-118 represents one the most prominent structural difference between PfGST and other GSTs. Our results demonstrate that truncation, increased rigidity or even a simple point mutation of this loop cause a dramatic change of the tetramerization kinetics that becomes hundred times slower than that observed in the native enzyme. Furthermore all mutants loose the positive cooperativity for hemin binding found in the native structure suggesting that the integrity of this peculiar loop is essential for intersubunit communication. Interestingly, the tetramerization process, that is very fast in the absence of GSH in the native enzyme, is prevented not only by GSH but even by GSSG. This result indicate that the protection of the parasite against free hemin is independent of the redox status of the cell.

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18

Navarro-Quezada, Aura R. "Molecular evolution of tropinone-reductase-like and tau GST genes duplicated in tandem in Brassicaceae". Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-76812.

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19

Bakas, Iolie C. "Cytochrome c peroxidase : its role in nitrosative stress and purification as a GST-fusion protein". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0006/MQ43634.pdf.

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20

Vrable, David Joseph. "A recombinant GST-EMBP440 fusion protein from sea urchin embryos that has myosin binding capabilities /". Connect to online version, 1997. http://hdl.handle.net/1989/3741.

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21

Giovanardi, Fabio <1984&gt. "Analysis of charge-transport properties in GST materials for next generation phase-change memory devices". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5583/4/giovanardi_fabio_tesi.pdf.

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Abstract (sommario):

The quest for universal memory is driving the rapid development of memories with superior all-round capabilities in non-volatility, high speed, high endurance and low power. The memory subsystem accounts for a significant cost and power budget of a computer system. Current DRAM-based main memory systems are starting to hit the power and cost limit. To resolve this issue the industry is improving existing technologies such as Flash and exploring new ones. Among those new technologies is the Phase Change Memory (PCM), which overcomes some of the shortcomings of the Flash such as durability and scalability. This alternative non-volatile memory technology, which uses resistance contrast in phase-change materials, offers more density relative to DRAM, and can help to increase main memory capacity of future systems while remaining within the cost and power constraints. Chalcogenide materials can suitably be exploited for manufacturing phase-change memory devices. Charge transport in amorphous chalcogenide-GST used for memory devices is modeled using two contributions: hopping of trapped electrons and motion of band electrons in extended states. Crystalline GST exhibits an almost Ohmic I(V) curve. In contrast amorphous GST shows a high resistance at low biases while, above a threshold voltage, a transition takes place from a highly resistive to a conductive state, characterized by a negative differential-resistance behavior. A clear and complete understanding of the threshold behavior of the amorphous phase is fundamental for exploiting such materials in the fabrication of innovative nonvolatile memories. The type of feedback that produces the snapback phenomenon is described as a filamentation in energy that is controlled by electron–electron interactions between trapped electrons and band electrons. The model thus derived is implemented within a state-of-the-art simulator. An analytical version of the model is also derived and is useful for discussing the snapback behavior and the scaling properties of the device.
Lo sviluppo dei sistemi di memoria di futura generazione è guidato principalmente dalla ricerca di una tecnologia in grado di superare quelle attuali in ogni loro specifica di funzionamento, dalla ritenzione di dato alla velocità di accesso, migliorandone la durata e riducendo il dispendio energetico. Il sottosistema delle memorie assorbe una parte significativa delle risorse del macro sistema costituito dal calcolatore, tanto da aver quasi raggiunto il limite tecnologico nel caso delle odierne memorie di tipo DRAM. La soluzione più promettente sembra essere quella delle memorie a cambiamento di fase (PCM), in grado di colmare anche i limiti mostrati dalla tecnologia Flash nell’ambito della durata e scalabilità. I materiali che consentono di realizzare dispostivi a cambiamento di fase pilotato elettricamente appartengono alla famiglia dei calcogenuri. Tra i diversi composti calcogenuri quello attualmente identificato come soluzione più promettente è il Ge2Sb2Te5 (GST). Il trasporto di carica all’interno di dispositivi di memoria realizzati con tali materiali è stato modellato considerando l’azione di due contributi differenti: hopping di cariche intrappolate e moto di elettroni liberi in stati estesi. Il GST mostra un comportamento elettrico pressoché Ohmico in fase cristallina mentre, in fase amorfa, risulta essere poco conduttivo per basse correnti fino al superamento di una tensione di soglia oltre la quale si assiste al passaggio da uno stato altamente resistivo ad uno altamente conduttivo, caratterizzato da un andamento a resistenza differenziale negativa (NDR). Il meccanismo retroattivo che induce il fenomeno di snapback viene descritto come filamentazione in energia controllata dalle interazioni tra elettroni liberi ed elettroni intrappolati. Il modello fisico ricavato è stato implementato all’interno di un simulatore di dispositivi di ultima generazione ed è stato in seguito riprodotto in una versione analitica semplificata in grado, però, di permettere una prima analisi del comportamento elettrico del dispositivo e delle sue proprietà di scaling.

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22

Giovanardi, Fabio <1984&gt. "Analysis of charge-transport properties in GST materials for next generation phase-change memory devices". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5583/.

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Abstract (sommario):

The quest for universal memory is driving the rapid development of memories with superior all-round capabilities in non-volatility, high speed, high endurance and low power. The memory subsystem accounts for a significant cost and power budget of a computer system. Current DRAM-based main memory systems are starting to hit the power and cost limit. To resolve this issue the industry is improving existing technologies such as Flash and exploring new ones. Among those new technologies is the Phase Change Memory (PCM), which overcomes some of the shortcomings of the Flash such as durability and scalability. This alternative non-volatile memory technology, which uses resistance contrast in phase-change materials, offers more density relative to DRAM, and can help to increase main memory capacity of future systems while remaining within the cost and power constraints. Chalcogenide materials can suitably be exploited for manufacturing phase-change memory devices. Charge transport in amorphous chalcogenide-GST used for memory devices is modeled using two contributions: hopping of trapped electrons and motion of band electrons in extended states. Crystalline GST exhibits an almost Ohmic I(V) curve. In contrast amorphous GST shows a high resistance at low biases while, above a threshold voltage, a transition takes place from a highly resistive to a conductive state, characterized by a negative differential-resistance behavior. A clear and complete understanding of the threshold behavior of the amorphous phase is fundamental for exploiting such materials in the fabrication of innovative nonvolatile memories. The type of feedback that produces the snapback phenomenon is described as a filamentation in energy that is controlled by electron–electron interactions between trapped electrons and band electrons. The model thus derived is implemented within a state-of-the-art simulator. An analytical version of the model is also derived and is useful for discussing the snapback behavior and the scaling properties of the device.
Lo sviluppo dei sistemi di memoria di futura generazione è guidato principalmente dalla ricerca di una tecnologia in grado di superare quelle attuali in ogni loro specifica di funzionamento, dalla ritenzione di dato alla velocità di accesso, migliorandone la durata e riducendo il dispendio energetico. Il sottosistema delle memorie assorbe una parte significativa delle risorse del macro sistema costituito dal calcolatore, tanto da aver quasi raggiunto il limite tecnologico nel caso delle odierne memorie di tipo DRAM. La soluzione più promettente sembra essere quella delle memorie a cambiamento di fase (PCM), in grado di colmare anche i limiti mostrati dalla tecnologia Flash nell’ambito della durata e scalabilità. I materiali che consentono di realizzare dispostivi a cambiamento di fase pilotato elettricamente appartengono alla famiglia dei calcogenuri. Tra i diversi composti calcogenuri quello attualmente identificato come soluzione più promettente è il Ge2Sb2Te5 (GST). Il trasporto di carica all’interno di dispositivi di memoria realizzati con tali materiali è stato modellato considerando l’azione di due contributi differenti: hopping di cariche intrappolate e moto di elettroni liberi in stati estesi. Il GST mostra un comportamento elettrico pressoché Ohmico in fase cristallina mentre, in fase amorfa, risulta essere poco conduttivo per basse correnti fino al superamento di una tensione di soglia oltre la quale si assiste al passaggio da uno stato altamente resistivo ad uno altamente conduttivo, caratterizzato da un andamento a resistenza differenziale negativa (NDR). Il meccanismo retroattivo che induce il fenomeno di snapback viene descritto come filamentazione in energia controllata dalle interazioni tra elettroni liberi ed elettroni intrappolati. Il modello fisico ricavato è stato implementato all’interno di un simulatore di dispositivi di ultima generazione ed è stato in seguito riprodotto in una versione analitica semplificata in grado, però, di permettere una prima analisi del comportamento elettrico del dispositivo e delle sue proprietà di scaling.

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23

Gorzitze-Maxey, Adrian Dale. "Development of a Fluorescence-Based Screen for Glutathione-S-Transferase Inhibitors". Ohio Dominican University Honors Theses / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=oduhonors1449612834.

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24

Rubensam, Jane Maria. "Estudos sobre atividade de calpastatina em carne bovina e obtenção de anticorpo policlonal anti GST-calpastatina". [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255369.

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Orientadores: Pedro Eduardo de Felicio, Carlos Termignoni
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-07-25T14:10:21Z (GMT). No. of bitstreams: 1 Rubensam_JaneMaria_D.pdf: 3334187 bytes, checksum: 061c9d779e7f5da6e43706dd56bfc44e (MD5) Previous issue date: 1999
Resumo: Este trabalho teve como objetivo estudar a relação da atividade de calpastatina e a força de cisalhamento da carne bovina bem como produzir anticorpo policlonal anti-calpastatina para futuro uso em estudos do potencial da calpastatina como indicador da maciez tendo em vista que esta característica é considerada como a mais importante para a qualidade sensorial da carne bovina. Foram realizados dois experimentos. No primeiro, estudou-se a influência do genótipo B0S indicus na atividade de calpastatina e na textura do músculo longissimus dorsi de novilhos criados no Sul do Brasil e a variabilidade destas características. A atividade de calpastatina foi determinada pelo ensaio de inibição da m-calpaína e a textura através da força de cisalhamento (Warner Bratzler Shear). Amostras de contrafilé (músculo L. dorsi) provenientes de 26 bovinos, sendo 14 Polled Hereford (HH), sete ¾ Hereford 1/4Nelore (3/4H1/4N) e cinco S/8Hereford 3/8Nelore (S/8H3/8N), machos castrados, abatidos aos dois anos de. idade, foram coletadas 24 h após o abate e analisadas quanto à atividade de calpastatina e textura, tanto no 1 ° dia post moriem quanto após um período de maturação de 10 dias a 2° C. A carne de novilhos S/8H3/8N apresentou, no 1° dia, maior (p0,05) entre os grupos HH e 3/4H1/4N para as mesmas características. Após 10 dias, houve uma diferença na atividade de calpastatina, porém não significativa (p>O,OS), entre o grupo 5/8H3/8N (1,S7U/g) e os demais (HH=1,23U/g; 3/4H1/4N=1,35U/g), e diferença significativa entre os grupos HH e S/8H3/8N para força de cisalhamento (3,67 e 5,00kg, respectivamente).Neste experimento, concluiu-se que a atividade de calpastatina determinada 24 horas post moriem, pode ser útil para a previsão da textura da carne, maturada ou não. Além disso, a participação do genótipo B.os indicus nos rebanhos bovinos da Região Sul poderá resultar em carne de pior textura. No segundo experimento, o gene contendo os domínios 2, 3, 4 e a região não traduzida 3' da calpastatina muscular bovina, inserido no vetor pGEX-5X-2, denominado pBSA1 (Killefer & Koohmaraie, 1994), gentilmente cedido pelo Dr. Mohammad Koohmaraie, pesquisador líder do Meat Animal Research Center, Clay Center, Nebraska, EUA, foi utilizado para expressão da calpastatina na forma de GST-calpastatina, em células de Escherichia coli AD202 DH5a. Após purificação em coluna de Glutathione-Sepharose 4B, inoculou-se 100 µg de GSTcalpastatina em coelho, via subcutânea, por 4 vezes, com intervalos de 21 dias. O anticorpo policlonal anti GST -calpastatina, purificado em Proteína G HiTrap, reconheceu calpastatina de extrato muscular bovino aquecido, com 67 kDa, através do método Western Blot. Através do teste ELlSA (Enzyme Linked Immunosorbent Assay) de. competição, o anticorpo policlonal anti GSTcalpastatina, em concentrações de 60 a 230 µg IgG/poço, reconheceu 70 mU da calpastatina muscular presente no extrato aquecido numa concentração dez vezes maior. GST -calpastatina também foi expressada em E. coli XL 1 Blue e, após purificação em cromatografia de afinidade, foi inoculada em coelho para obtenção de anticorpo policlonal. Este anticorpo foi utilizado em teste ELISA de captura de anticorpos para identificação da calpastatina muscular bovina em extrato muscular aquecido. A concentração de anticorpo policlonal anti GST -calpastatina, igual a 45 µg/ml, apresentou resposta proporcional à quantidade de calpastatina no extrato muscular. A produção e purificação de anticorpo policlonal anti GST -calpastatina constituirá um importante passo rumo ao desenvolvimento de testes, para determinação direta da atividade de calpastatina em amostras de músculos bovinos coletados por biópsia
Abstract: The objective of this work was to study the relationship between the longissimus dorsi muscle calpastatin activity and the shear force trom steers of different genotypes as well to produce polyclonal anti-calpastatin antibodies to be used as meat tenderness predictor in further research. Tenderness is considered the most important sensory quality attribute of beef. Two experiments were conducted. In the first, it was studied the Bos indicus genotype influence on calpastatin activity and texture of boneless rib steaks (longissimus dorsi muscle) at 24 hours after slaughter and at the 10th day of aging at 2°C from steers raised in thé South of Brazil. Calpastatin activity was determined by m-calpain inhibition assay anel texture by shear force (Warner-Bratzler). Beef rib samples from 26 steers, being 14 Polled Hereford (HH), seven 3/4 Hereford 1/4 Nelore (3/4H1/4N) and five 5/8 Hereford 3/8 Nelore (5/8H3/8N) were analysed. Rib samples from 5/8H3/8N steers showed higher (p<0.05) calpastatin activity and shear force values than beef trom HH and 3/4H1/4N steers in the 1st day. No differences (p>0.05) were detected in the same traits between groups HH and 3/4H1I4N. After 10 days of aging, there was a difference in calpastatin activity, although non-significant (p>0.05), amongst group 5/8H3/8N (1.57U/g) and others (HH=1.23U/g; 3/4H1/4N=1.35U/g), and a significant difference in shear force between groups HH and 5/8H3/8N (3.67 and 5.00kg, respectively). It was concluded that the calpastatin activity determined 24 hs post mortem can be useful to predict the texture of beef, aged or not. Also, the increasing participation of Bos indicus genotype in the South Region cattle herds, besides the productivity advantages, may result in beef of lower texture quality. In the second experiment, polyclonal antibodies were raised in rabbits from a cloned pBSA1 (vector pGEX-5X-2, Pharmacia) encoding domains 2, 3, 4 and the 3' untranslated region of bovine calpastatin gene, kindly provided by Or. Mohammad Koohmaraie, leader researcher trom Meat Animal Research Center Roman L. Hurska, Clay Center, Nebraska, USA.. The cloned pBSA1 (KILLEFER & KOOHMARAIE, 1994) was used to expression of a GST-calpastatin form in Escherichia coli AD202 and DH5a cells. After purification in Glutathione Sepharose 4B column, aliquot of 100 µg GST-calpastatin was inoculated in rabbit, four times with 21 day intervals. The polyclonal antibodies purified in Protein G HiTrap recognized a 67 kDa protein from prerigor bovine heated muscle homogenates by Western blot method. By ELlSA competition assay, polyclonal anti-GST-calpastatin antibodies within the range of 60 to 230µg IgG/well detected until 70 mU of calpastatin trom bovine prerigor longissimus dorsi muscle homogenate in which original activity was ten times higher. GST -calpastatin was also expressed in E. coli XL 1 Blue that after an affinity purification was used to raise polyclonal antibodies in rabbits. The polyclonal antibodies anti-GST-calpastatin were used to perform an antibodies capture ELlSA test to identify calpastatin from a heated muscle homogenate. A 45 J..lg/ml of antiGST -calpastatin polyclonal antibodies concentration presented a proportional response in relation to the muscle heated homogenate calpastatin concentration. The polyclonal anti-GST -cal pastati n antibodies obtained in this work could be used to develop field tests useful to determine calpastatin activity in bovine muscles collected by biopsy
Doutorado
Doutor em Tecnologia de Alimentos

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25

Nishimura, Deborah Sanae. "Caracterização molecular da glutationa S-transferase de cana-de-açúcar (Saccharum spp.) em resposta a aplicação de herbicidas". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/64/64133/tde-18122007-142749/.

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A glutationa S-transferase (GST) tem a capacidade de conferir resistência do tipo não-alvo aos efeitos danosos de certos herbicidas em várias culturas, principalmente gramíneas. Entretanto, o papel das GSTs em relação aos herbicidas em cana-de-açúcar é desconhecido, e tal elucidação poderia auxiliar na redução de perdas de produtividade e/ou aumento na eficiência de produção. O objetivo desse trabalho foi caracterizar as diversas classes de GST de cana-de-açúcar por análise filogenética e padrão de expressão por amplificação quantitativa de transcritos reversos (RT-qPCR). Foi realizada no banco de dados de Saccharum Gene Index a busca completa das seqüências codificadoras de GST referentes às classes Phi, Tau, Theta e Zeta, baseando-se nos 61 genes de GST de arroz; estas foram traduzidas e empregadas em análise filogenética. Foram identificados 18 agrupamentos de ESTs codificando GSTs, totalizando 355 transcritos das 255.635 seqüências disponíveis no banco de dados. A análise filogenética identificou 7 agrupamentos como pertencentes à classe Phi (denominados ScGSTF), 7 como Tau (ScGSTU), 1 como Theta (ScGSTT), e 3 como Zeta (ScGSTZ); respectivamente. As classes Phi e Tau, consideradas planta-específica, foram as mais representativas em termos de número de agrupamentos de ESTs em relação à Theta e Zeta (mamífero-específica). Os 18 agrupamentos de cana-de-açúcar equivalem aos genes mais expressos em termos de número de ESTs individuais em arroz. Foram extraídos RNA de diversos tecidos/órgãos, e de tecido foliar das cultivares \'SP87-365\' e \'SP80-3280\' coletados a 0 e 48 h após tratamento com herbicidas, seguida da síntese de cDNA e RT-qPCR. O gene da proteína ribossômica rpl35-4 foi determinado como referência nas análises de expressão. A expressão nos tecidos/órgãos mostraram que os genes ScGSTF3, ScGSTU8 e ScGSTU13 foram menos expressos no colmo, inflorescência, meristema e raiz em relação ao limbo foliar; ScGSTF4, ScGSTF6, ScGSTF14 e ScGSTF15 foram mais expressos no colmo; ScGSTF5, ScGSTU1, ScGSTU17, ScGSTU31, ScGSTU39 e ScGSTT1 na inflorescência; e ScGSTZ1 foi único mais expresso no meristema. De forma geral, todas as classes tiveram expressão detectada nos tecidos, mas os genes da Phi e Tau foram os mais expressos. Os genes da classe Phi foram mais expressos no colmo em relação aos demais; os da classe Tau e Theta na inflorescência; e os da Zeta no meristema. A validação a 0 h determinou que os genes ScGSTF3, ScGSTF4, ScGSTU8, ScGSTU13 e ScGSTU17 foram os mais expressos na cultivar \'SP80-3280\' em relação à \'SP87-365\'. As evidentes diferenças na expressão basal entre as cultivares foram dos genes das classes Phi e Tau. Com relação à expressão das GSTs 48 h após aplicação dos herbicidas, foi observado que a aplicação de Ametryn ou Diuron, os genes de GST foram induzidos, enquanto foram reprimidos com Imazapic ou Isoxaflutole. Os genes ScGSTF3, ScGSTF4, ScGSTU13 e ScGSTU17 foram os mais expressos nas cultivares tratadas com os herbicidas; e foram considerados possíveis candidatos a associação em resposta a desintoxicação desses herbicidas. O Southern blot determinou que o maior número de cópias de GST em cana-de-açúcar foi os pertencentes às classes Phi e Tau, sendo nas classes Zeta e Theta, menos freqüentes
Glutathione S-transferase (GST) has the ability to confer non-target tolerance to damaging effects of certain herbicides in various crops, especially grasses. However, the role of GSTs in relation to herbicide tolerance in sugarcane s is unknown, and its elucidation could help in reducing yield losses and/or increase in production efficiency. The objective of this work was to characterize the various classes of sugarcane GSTs by phylogenetic analyses and expression profile using RTqPCR. A complete search at the Saccharum Gene Index database was conducted for sequences encoding GSTs from the classes Phi, Tau, Theta and Zeta, based on 61 rice GST genes; the conceptually translated sequences were used in the phylogenetic analyses. Eighteen EST clusters encoding GSTs were identified, in a total of 355 transcripts out of the 255,635 available sequences at the database. Phylogenetic analysis identified 7 groups as belonging to Phi class (denominated ScGSTF), 7 as Tau (ScGSTU), one as Theta (ScGSTT), and 3 as Zeta (ScGSTZ); respectively. The Phi and Tau classes, considered plant-specific, were the most frequent in terms of number of EST clusters in comparison to Theta and Zeta (mammal-specific). The 18 groups of sugarcane ESTs were equivalent to the mostly expressed ortologues in rice. Total RNA from various tissues and organs, and from leaves from cultivars \'SP87-365\' and \'SP80-3280\', collected at 0 and e 48 h after treatment with herbicides were obtained and converted into cDNA, and analyzed by RT-qPCR. The transcript of the ribosomal protein rpl35-4 was established as gene reference for the RT-qPCR analyses. The analyses of expression in tissues/organs demonstrated that the genes ScGSTF3, ScGSTU8 and ScGSTU13 were less expressed in stem, inflorescence, meristem and roots in relation to leaf blades; ScGSTF4, ScGSTF6, ScGSTF14 and ScGSTF15 were more expressed in stems; ScGSTF5, ScGSTU1, ScGSTU17, ScGSTU31, ScGSTU39 and ScGSTT1 in the inflorescence; and ScGSTZ1 was the only more expressed in the meristem. In general, all classes had gene member expression detected in the tissues, but the genes from Phi and Tau were the most expressed. The genes from class Phi were more expressed in the stem in comparison to the others; genes from classes Tau and Theta were more expressed in the inflorescence; and the ones from Zeta in meristem. Gene expression validation at 0 or 48 h after treatment with herbicides determined that ScGSTF3, ScGSTF4, ScGSTU8, ScGSTU13 and ScGSTU17 were more expressed in cultivar \'SP80-3280\' than \'SP87-365\'. The more evident differences in basal expression between cultivars were for genes from classes Phi and Tau. In response to herbicides treatment, GSTs expression was higher in response to Ametryn or Diuron in comparison to Imazapic or Isoxaflutole. Genes ScGSTF3, ScGSTF4, ScGSTU13 and ScGSTU17 displayed more difference in expression at 48 h between cultivars, and might be associated with differences in herbicide detoxification. Southern blot analyses determined that a larger number of GST gene copies in sugarcane from classes Phi and Tau, with less copies from classes Zeta and Theta

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26

Hernandez, Gerardo Rodriguez. "Study of mixed mode electro-optical operations of Ge2Sb2Te5". Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:5bb8c1f5-2f4b-4eb0-a61a-3978af04211f.

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Chalcogenide based Phase Change Materials are currently of great technological interest in the growing field of optoelectronics. Ge₂Sb₂Te₅ (GST) is the most widely studied phase change material, and it has been commercially used in both optical and electronic data storage applications, due to its ability to switch between two different atomic configurations, at high speed and with low power consumption, as well as its high optical and electrical contrast between amorphous and crystalline states. Despite its well-known optical and electrical properties, the operation in combination of optical and electrical domains has not yet been fully investigated. This work studies the operation of GST nano-devices exposed to a combination of optical and electrical stimuli or mixed mode by asking, is it possible to electrically measure an optically induced phase change, or vice versa? If so, how do the optical and electrical responses relate to each other, and is it possible to operate GST with a combination of optical and electrical signals? What are the technical constraints that need to be considered in order to fabricate GST devices that could be operated either optically or electrically? In order to answer these questions, experiments that characterized the optical and electrical responses of GST based nano-devices were performed. It was found that different crystallization mechanisms may have influence in the response, and that the thermal and optical design characteristics of the device play a key role in its operation. Finally a proof of principle, of an opto-electonic memory device that can be read electrically, reset optically and write electrically, is presented. This opens up possibilities for the development of new opto-eloectronic applications such as non-volatile interfaces between future photonics and electronics, high speed optical communication detectors, high speed cameras, artificial retinas and many more.

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27

Maia, Rafael Trindade. "Análise in silico e polimorfismo genético das glutationa stransferases da classe epsilon de anopheles gambiae (diptera: culicidae): possíveis implicações na resistência a inseticidas químicos". Universidade Federal de Pernambuco, 2013. https://repositorio.ufpe.br/handle/123456789/11996.

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Submitted by Milena Dias (milena.dias@ufpe.br) on 2015-03-11T17:49:05Z No. of bitstreams: 2 Tese Rafael Trindade Maia.pdf: 4595214 bytes, checksum: 9e51b91025a00458c05287160877d452 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5)
Made available in DSpace on 2015-03-11T17:49:05Z (GMT). No. of bitstreams: 2 Tese Rafael Trindade Maia.pdf: 4595214 bytes, checksum: 9e51b91025a00458c05287160877d452 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2013
O mosquito Anopheles gambiae (Diptera: Culicidae) é considerado o principal vetor do Plasmodium, o agente etiológico da malária, a doença parasitária que mais leva ao óbito em todo o mundo. O uso intensivo de alguns inseticidas químicos, entre os quais o DDT, direcionados para o controle desse vetor, levou à seleção de linhagens resistentes de An. gambiae. Desta forma, os mecanismos de resistência aos inseticidas vêm sendo amplamente estudados com o intuito de desenvolver novas estratégias de controle populacional do vetor. As glutationa s-transferases (GSTs) são enzimas de detoxificação celular que desempenham um importante papel biológico no metabolismo de xenobióticos através da conjugação da glutationa reduzida (GSH), tornandoos mais solúveis e facilmente excretados da célula. As GSTs da classe epsilon em An. gambiae (AgGSTE) apresentam atividade anti-DDT, especialmente a AgGSTE2, cuja estrutura encontra-se disponível no PDB. Também já foi demonstrado que a enzima AgGSTE5, cuja estrutura tridimensional ainda não foi elucidada, apresentou super expressão em presença do DDT. Assim, o objetivo do presente trabalho foi construir e validar um modelo tridimensional para elicidação da estrutura da AgGSTE5 através da modelagem comparativa e simular a dinâmica molecular da AgGSTE2 e AgGSTE5 e de uma isoforma mutante (AgGSTE2mut). Nas simulações de Dinâmica Molecular (DM) foram feitas por um período de 50 nanossegundos com e sem o ligante (GSH). Após a dinâmica, as três enzimas foram submetidas ao docking molecular contra os compostos DDT, CDNB, carbaril, malation e cipermetrina. Também foi analisado o polimorfismo genético e a taxa de mutação para os genes AgGSTE2 e AgGSTE5. A análise da seqüência dos genes apontou seleção purificadora para o AgGSTE2 e seleção positiva para o AgGSTE5 em populações de sete países da África. Os resultados demonstraram que as proteínas têm dinâmicas diferentes e interagem com os substratos de modo diferente. As mutações da AgGSTE2mut alteram sua dinâmica e modo de ação, sendo esta enzima particularmente capaz de se ligar ao DDT, com energia de ligação menor que as outras. Finalmente, os resultados do presente trabalho sugerem que estas enzimas desempenharam um papel crucial na adaptação de An. gambiae ao seu habitat e possivelmente a evolutibilidade destas GSTs teve participação neste processo evolutivo, sendo portanto alvos potenciais para o desenvolvimento de novas ferramentas de controle. Conclui-se que o papel da AgGSTE2 e AgGSTE5 na metabolização de inseticidas é importante para a adaptação do An. gambiae e o modo de ação destas enzimas deve ser entendido como uma importante via metabólica a ser interferida com o propósito de melhorar os inseticidas e métodos de controle. Os resultados permitem concluir que o modelo teórico é válido e que a AgGSTE2, AgGSTE2mut e AgGSTE5 apresentam diferenças na dinâmica e no modo de ligação aos compostos químicos estudados, o que provavelmente reflete em uma divergência funcional destas enzimas.

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Davies, Warren Raymond, e warren davies@optusnet com au. "Effects of the Cyanobacterium Nodularia spumigena on Selected Estuarine Fauna". RMIT University. Applied Sciences, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080415.164533.

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Nodularia spumigena is an estuarine cyanobacteria that produces the toxin nodularin. This toxic cyanobacteria is known to have caused death to domestic and wild animals and is recognised as dangerous to human health. N. spumigena causes harmful algal blooms in many parts of the world including Australia. The toxic solutes of N. spumigena are potentially dangerous when contact is made to contaminated water bodies or is ingested by primary consumers. In Australia blooms of N. spumigena are common in the Gippsland Lakes in South-eastern Victoria and cause socio - economic hardships to the local communities. This PhD investigates the toxic effects of N. spumigena and its solutes to a range of aquatic life. A method known as SPME - HPLC showed promise in environmental monitoring of N. spumigena toxins by measuring nodularin from water samples. Other research presented study into the lethal and sublethal effects of on an extract from N. spumigena to aquatic fauna. Resu lts showed the N. spumigena extract was not lethal to many aquatic fauna although zooplankton from the Gippsland Lakes showed mortality at environmental relevant levels. Biochemical studies focusing on animal detoxification and antioxidation enzymes and DNA integrity showed sublethal effects to the N. spumigena extract. Results presented in this thesis show that an extract of N. spumigena elicited detoxification and antioxidation responses in animals tested. Furthermore, the use of the COMET assay showed increased damage to DNA of animals tested. Results also showed that different organs in animals tested responded differently to the aqueous extract, suggesting mode of uptake maybe important in toxicosis. Further, feeding studies with N. spumigena help elucidate mode of uptake using enzyme response biomarkers. The overall results of this research provided an assessment of the toxic affects of N. spumigena on aquatic fauna with special reference to the Gippsland Lakes, Victoria, Australia.

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Ulusoy, Gulen. "Association Of Cyp2e1, Nqo1 And Gst Genetic Polymorphisms With Risk Of Acute Lymphoblastic Leukemia In Turkish Children". Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610470/index.pdf.

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Acute lymphoblastic leukemia (ALL) is the most common type of cancer affecting children in the world and in our country. The exact molecular etiology of the disease still remains to be elucidated. This study hypothesized that four genes, namely CYP2E1*5B, *6, and *7B, NQO1*2 SNPs, GSTM1 null and GSTT1 null, alone or in combination, could contribute to the risk of development of childhood ALL. Also interactions of these polymorphisms with non-genetic risk factors were investigated. The genotyping of these polymorphisms were done on 209 healthy subjects, and 185 patients with childhood ALL, in Turkish population. Venous blood samples were collected and genomic DNA was isolated from these samples. Genotyping was done by PCR-RFLP techniques. In the case-control analyses for the risk of development of childhood ALL, only GSTT1 null was found to be associated with the development of disease (OR= 1.8, p=0.01). CYP2E1*5B and *6 combination showed an increased risk of 2.7 fold (p= 0.04). Also co-presence of CYP2E1*6-GSTT1 and CYP2E1*7B-GSTT1 polymorphisms increased the risk significantly above 4.0 fold. The risk increased more to 7.6 fold, when CYP2E1*5B,*6 and GSTT1 null were considered together, with borderline significance (p=0.04). When interaction of exposure to cigarette smoke and genetic polymorphisms were investigated, NQO1*2 and GSTM1 null were turned out to be significant risk factors for the development of disease when the parental or child&rsquo
s postnatal exposure to cigarette smoke was considered. This study presented several new findings to the literature in terms of genetic epidemiology of childhood ALL. The present work would also contribute to public health in determining the susceptibility of the Turkish population to childhood ALL.

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GuimarÃes, Antonio Walter Gadelha. "Impact of changes in gdp in the collection of the state of gst by economic sectors PiauÃ". Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7512.

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nÃo hÃ
This work aims at analyzing the impact of changes in Gross Domestic Product (GDP) on the collection of VAT in the State of PiauÃ, studying separately the fluctuations of the collections in the primary, secondary and tertiary. Used in developing this work ICMS and GDP data, which were analyzed using econometric regression model for time series with panel data, to identify the elasticities of the PIB variable that will affect the ICMS variable. The results show clearly that the growth rate of the ICMS follows the growth rate of GDP, the total level, and specifically, this behavior was repeated in the secondary and tertiary sectors of the economy of the state of Piaui.
O presente trabalho possui como objetivo principal analisar o impacto das alteraÃÃes do Produto Interno Bruto (PIB) sobre a arrecadaÃÃo do ICMS no Estado do PiauÃ, estudando, separadamente, as oscilaÃÃes das arrecadaÃÃes nos setores primÃrio, secundÃrio e terciÃrio. Foram utilizados no desenvolvimento desse trabalho dados de ICMS e PIB, os quais foram analisados atravÃs de modelo economÃtrico de regressÃo por sÃries temporais com dados em painel, visando identificar as elasticidades da variÃvel PIB que afetarÃ a variÃvel ICMS. Os resultados obtidos demonstram que a taxa de crescimento do ICMS segue a taxa de crescimento do PIB, a nÃvel total, e, especificamente, esse comportamento repetiu-se nos setores secundÃrio e terciÃrio da economia do Estado do PiauÃ.

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Mendonça, Rafaela Silva. "O papel da insularina, uma disintegrina recombinante (GST-INS), em processos de progressão tumoral: estudos in vitro". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/42/42133/tde-12092016-104116/.

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Plaquetas e células tumorais interagem em uma reação cruzada com proteínas do plasma, via integrina αIIbβ3 e αvβ3, respectivamente. A integrina αvβ3 também encontra-se presente na angiogênese tumoral. O objetivo desse trabalho foi avaliar a GST-INS, uma disintegrina recombinante do veneno de Bothrops insularis em eventos da progressão tumoral. Em condições estáticas, GST-INS foi capaz de inibir totalmente a adesão de células HUVECs e SK-MEL-28 às plaquetas em comparação ao controle e ao Aggrastat® (inibidor seletivo da integrina αIIbβ3). Além de inibir a TCIPA (agregação plaquetária induzida por células tumorais) a GST-INS também inibiu a invasão de SK-MEL-28 em substrato de matrigel. Células t.End.1 ou SK-MEL-28 pré-incubadas com GST-INS não formaram túbulos no substrato de matrigel. Análise por microscopia confocal mostrou que GST-INS liga-se a integrina αv presente nas células SK-MEL-28. Nossos resultados sugerem que essa disintegrina pode ser utilizada como potencial ferramenta no estudo e desenvolvimento de antiangiogênicos e antimetastáticos.
Platelets and tumor cells interact in a cross-react with plasma proteins via integrin αIIbβ3 and αvβ3 , respectively.The integrin αvβ3 is also strongly stimulated in tumor angiogenesis. The aim of this study was to evaluate the ability of GST-INS, a recombinant disintegrin from Bothrops insularis venom on events of tumor progression. Under static conditions, GST-INS was able to completely inhibit the adhesion of endothelial cells (HUVECs) and melanoma cells (SK-MEL-28) to platelets compared to control and Aggrastat® (selective inhibitor of integrin αIIbβ3). In addition, GST-INS inhibit TCIPA (platelet aggregation induced by tumor cells) GST-INS also inhibited SK-MEL-28 on matrigel invasion substrate. t.End.1 cells or SK-MEL-28 pre-incubated with GST-INS were not able to form tubules in matrigel substrate. Analysis by confocal microscopy showed that GST-INS binds to integrin αv present in SK-MEL-28 cells. The results suggest that disintegrin can be used as a potential tool in the study and development of antiangiogenic and antimetastatic.

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32

Manduzio, Hélène. "Étude des modifications d'expression protéique sous l'effet d'un stress environnemental chez deux bivalves estuariens, la moule zébrée (Dreissena polymorpha) et la moule bleue (Mytilus edulis) : suivi de marqueurs de défense cellulaire et approche protéomique". Le Havre, 2004. http://www.theses.fr/2004LEHA0006.

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Ce travail de thèse a été initié dans le but d'étudier les modifications d'expression protéique induites chez des organismes sentinelles soumis à différentes conditions de stress environnementaux. Il a pour objectif principal d'identifier les acteurs impliqués dans la réponse aux contaminants aquatiques et de mieux comprendre les mécanismes cellulaires et moléculaires mis en jeu, qu'il s'agisse de modifications liées à la toxicité du xénobiotique ou les réponses adaptatives des organismes. Deux modèles biologiques ont été choisis, la moule zébrée (Dreissena polymorpha) et la moule bleue (Mytilus edulis). La première approche a été ciblée sur l'étude du stress oxydant, abordée par la mesure des activités antioxydantes glutathion réductase, glutathion peroxidase et superoxyde dismutase et d'une enzyme de détoxication, la glutathion S-transferase. La deuxième approche est ouverte et consiste en une étude protéomique réalisée sur des animaux soumis à différentes situations de stress
This research was initiated in order to study the modifications of protein expression induced in sentinel organisms exposed to various conditions of environmental stress. The main goal was to identify molecular actors involved in the response of bivalves to contaminants and to better understand the cellular and molecular mechanisms activated being either alterations related to the toxicity of xenobiotics or adaptive answer of the organisms. Two bivalve models were chosen, the zebra mussel Dreissena polymorpha, a freshwater species, and the blue mussel Mytilus edulis, a marine water species. The first approach was targeted on the study of oxidative stress by measuring the activity levels of the antioxidant enzymes glutathione reductase, glutathione peroxidase and superoxide dismutase, and of the detoxification enzyme, glutathione S-transferase. The second approach was open-framed and consisted in a proteomic study carried out on blue mussels submitted to various environmental conditions

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33

Ozcelik, Aysun. "Association Of The Cyp2e1, Fmo3, Nqo1, Gst And Nos3 Genetic Polymorphisms With Ischemic Stroke Risk In Turkish Population". Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613933/index.pdf.

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Stroke, a major cause of death and disability, is described as interruption or severe reduction of blood flow in cerebral arteries. Oxidative stress plays an important role in the pathogenesis of atherosclerosis and carotid atherosclerosis is a risk factor for stroke. Combination of multiple environmental and genetic risk factors is thought to increase susceptibility to the development of this disease. Therefore, investigation of the polymorphisms of drug metabolizing enzymes is of crucial importance to determine the molecular etiology of the disease. The main objective of this study was to investigate the possible association between polymorphisms of enzymes causing oxidative stress (CYP2E1, FMO3 and NOS3) and enzymes protecting against oxidative stress (GST and NQO1), and the pathogenesis of atherosclerosis and ischemic stroke risk. The study population consisted of 245 unrelated ischemic stroke patients and 145 healthy control subjects. There was no statistically difference between the patient and control groups in terms of age and gender. Hypertension, diabetes, smoking and obesity were found to be at least 2 times more common in stroke patients than controls. While total cholesterol, triglyceride and LDL-cholesterol level were higher in stroke patients, HDL-cholesterol level was lower in stroke patients when compared to controls. In the case-control analyses for the risk of ischemic stroke, CYP2E1*5B mutant allele, *5B was found to be associated with the development of disease (Odds Ratio
OR=7.876, 95%CI=1.025-60.525, P=0.019). In addition, significant difference was observed between stroke patients and controls with respect to CYP2E1*5B genotype distribution (OR=0.869, 95%CI=1.044-62.339, P=0.017). On the other hand, in the NQO1*2 polymorphism, together with NQO1 heterozygote (*1*2), NQO1 homozygote mutant (*2*2) genotype was found protective against ischemic stroke (OR=0.627, 95%CI=0.414-0.950, P=0.027). The risk of hypertensive individuals having stroke was highest in the FMO3 472GA group (OR=6.110, P=0.000). In diabetics, GSTP1 313AG genotype was found to be the highest risk factor for stroke (OR=3.808 P=0.001). On the other hand, NQO1 *1*2 heterozygote genotype was associated with 5 times increased risk for stroke in smokers (OR=5.000, P=0.000). In addition GSTM1 present genotype constituted 8 times increased stroke risk in obese individuals (OR=8.068, P=0.001). Logistic regression analysis revealed that hypertension, diabetes mellitus, obesity and smoking were significant risk factors for stroke. On the other hand, HDL-cholesterol and having NQO1 *1*2 heterozygote genotype were found to be protective factors against stroke.

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34

Barroso, SÃrgio Ricardo RebouÃas. "The computerization of the Secretary of the State of CearÃ and its effects on the collection of GST". Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=3872.

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nÃo hÃ
The Finance Department of CearÃ State â SEFAZ/CE passed in the last 14 years by several programs of structural and technological modernization and through them the computer science was more and more introduced in the institution. With resources caught through financing with the BID â Banco Interamericano de Desenvolvimento and own resources of the State it was invested only in the area of computer science around 115 millions of reals in this period. From 1994, when there was created officially the Centre of Data Processing of the SEFAZ, several systems of information were developed and started making easy not only the access of the taxpayers and accountants to the services of the institution, but also the work of the officials themselves in which it refers to the control of the processes, storage of data and tools for inspection. In this sense, this work proposes to analyse the effect of these investments on the tax revenue of ICMS for the SEFAZ. Through a model economic, it was come to the conclusion that the investments in informatization, when controlled for other factors, did not present any impact on the amount of ICMS collected by the SEFAZ in the period between 1995 and 2008.
A Secretaria da Fazenda do Estado do CearÃ (SEFAZ) passou, nos Ãltimos 14 anos, por vÃrios programas de modernizaÃÃo estrutural e tecnolÃgica e, atravÃs deles, a informÃtica foi sendo cada vez mais implantada na instituiÃÃo. Com recursos captados de financiamentos junto ao Banco Interamericano de Desenvolvimento (BID) e, com aporte tambÃm de recursos prÃprios do Estado, foram investidos somente na Ãrea de informÃtica cerca de 115 milhÃes de reais nesse perÃodo. Desde 1994, quando foi criado oficialmente o Centro de Processamento de Dados da SEFAZ, vÃrios sistemas de informaÃÃo foram desenvolvidos e postos em funcionamento, facilitando nÃo sÃ o acesso dos contribuintes e dos contadores aos serviÃos da instituiÃÃo, mas tambÃm o trabalho dos prÃprios funcionÃrios, no que se refere ao controle dos processos, da armazenagem de dados e das ferramentas para fiscalizaÃÃo. Neste sentido, este trabalho se propÃe a analisar o efeito desses investimentos sobre a arrecadaÃÃo de ICMS pela SEFAZ e, atravÃs de um modelo economÃtrico, chegou-se Ã conclusÃo de que tais investimentos em informatizaÃÃo, quando controlados por outros fatores, nÃo apresentaram nenhum impacto sobre o montante arrecadado de ICMS, no perÃodo entre 1995 e 2008.

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Landais, Florence. "Les glutathion s-transférases : étude de la GST mu chez les sujets sains et chez les alcooliques cirrhotiques". Bordeaux 2, 1990. http://www.theses.fr/1990BOR23023.

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36

Kiouseloglou, Athanasios. "Caractérisation et conception d' architectures basées sur des mémoires à changement de phase". Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT128/document.

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Les mémoires à base de semi-conducteur sont indispensables pour les dispositifs électroniques actuels. La demande croissante pour des dispositifs mémoires fortement miniaturisées a entraîné le développement de mémoires non volatiles fiables qui sont utilisées dans des systèmes informatiques pour le stockage de données et qui sont capables d'atteindre des débits de données élevés, avec des niveaux de dissipation d'énergie équivalents voire moindres que ceux des technologies mémoires actuelles.Parmi les technologies de mémoires non-volatiles émergentes, les mémoires à changement de phase (PCM) sont le candidat le plus prometteur pour remplacer la technologie de mémoire Flash conventionnelle. Les PCM offrent une grande variété de fonctions, comme une lecture et une écriture rapide, un excellent potentiel de miniaturisation, une compatibilité CMOS et des performances élevées de rétention de données à haute température et d'endurance, et peuvent donc ouvrir la voie à des applications non seulement pour les dispositifs mémoires, mais également pour les systèmes informatiques à hautes performances. Cependant, certains problèmes de fiabilité doivent encore être résolus pour que les PCM se positionnent comme un remplacement concurrentiel de la mémoire Flash.Ce travail se concentre sur l'étude de mémoires à changement de phase intégrées afin d'optimiser leurs performances et de proposer des solutions pour surmonter les principaux points critiques de la technologie, ciblant des applications à hautes températures. Afin d'améliorer la fiabilité de la technologie, la stœchiométrie du matériau à changement de phase a été conçue de façon appropriée et des dopants ont été ajoutés, optimisant ainsi la stabilité thermique. Une diminution de la vitesse de programmation est également rapportée, ainsi qu'un drift résiduel de la résistance de l'état de faiblement résistif vers des valeurs de résistance plus élevées au cours du temps.Une nouvelle technique de programmation est introduite, permettant d'améliorer la vitesse de programmation des dispositifs et, dans le même temps, de réduire avec succès le phénomène de drift en résistance. Par ailleurs, un algorithme de programmation des PCM multi-bits est présenté. Un générateur d'impulsions fournissant des impulsions avec la tension souhaitée en sortie a été conçu et testé expérimentalement, répondant aux demandes de programmation d'une grande variété de matériaux innovants et en permettant la programmation précise et l’optimisation des performances des PCM
Semiconductor memory has always been an indispensable component of modern electronic systems. The increasing demand for highly scaled memory devices has led to the development of reliable non-volatile memories that are used in computing systems for permanent data storage and are capable of achieving high data rates, with the same or lower power dissipation levels as those of current advanced memory solutions.Among the emerging non-volatile memory technologies, Phase Change Memory (PCM) is the most promising candidate to replace conventional Flash memory technology. PCM offers a wide variety of features, such as fast read and write access, excellent scalability potential, baseline CMOS compatibility and exceptional high-temperature data retention and endurance performances, and can therefore pave the way for applications not only in memory devices, but also in energy demanding, high-performance computer systems. However, some reliability issues still need to be addressed in order for PCM to establish itself as a competitive Flash memory replacement.This work focuses on the study of embedded Phase Change Memory in order to optimize device performance and propose solutions to overcome the key bottlenecks of the technology, targeting high-temperature applications. In order to enhance the reliability of the technology, the stoichiometry of the phase change material was appropriately engineered and dopants were added, resulting in an optimized thermal stability of the device. A decrease in the programming speed of the memory technology was also reported, along with a residual resistivity drift of the low resistance state towards higher resistance values over time.A novel programming technique was introduced, thanks to which the programming speed of the devices was improved and, at the same time, the resistance drift phenomenon could be successfully addressed. Moreover, an algorithm for programming PCM devices to multiple bits per cell using a single-pulse procedure was also presented. A pulse generator dedicated to provide the desired voltage pulses at its output was designed and experimentally tested, fitting the programming demands of a wide variety of materials under study and enabling accurate programming targeting the performance optimization of the technology

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37

Yilmaz, Duygu. "Mechanism Of Inhibition Of Cytochrome P4501a1 Associated 7-ethoxyresorufin O-deethylase (erod) Activity And Glutathione S-transferase (gst) Activities In Fish Liver By Phenolic Compounds/flavonoids". Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611497/index.pdf.

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Flavonoids, present in fruits, vegetables and beverages derived from plants, have been described as health-promoting, disease-preventing dietary supplements, and have activity as cancer preventive agents. The cancer protective effects of flavonoids have been attributed to a wide variety of mechanisms, including modulating enzyme activities resulting in the decreased carcinogenicity of xenobiotics. Cytochrome P4501A1 (CYP1A1) is a Phase I enzyme which is known to be involved in the activation of procarcinogens and Glutathione S-Transferase (GST) is a Phase II enzyme which is largely responsible for the detoxification of carcinogens. In this study, it was aimed to investigate the mechanisms of inhibition of CYP1A1 and GST activities of fish by phenolic compounds/flavonoids. Leaping mullet (Liza saliens), captured from highly polluted sites of izmir Bay, expressing high levels of CYP1A, were used in order to investigate these effects. It was demonstrated that all of the phenolic compounds/flavonoids used, exert an inhibitory effect on both CYP1A1 associated 7-Ethoxyresorufin-O-deethylase (EROD) activity and GST activities of fish, although the degree of inhibition was varied with the flavonoid used. Of the flavonoids tested, the most potent inhibitor of CYP1A1 associated EROD activity was found to be quercetin. The potency of the phenolic compounds/flavonoids to inhibit CYP1A1 associated EROD activity follow the sequence of quercetin >
resveratrol >
naringenin >
hesperidin >
rutin with IC50 values of 1.32 µ
M, 3.59 µ
M, 9.78 µ
M, 98.5 µ
M and 0.64 mM respectively. Quercetin, resveratrol, hesperidin and rutin were found to inhibit EROD activity in a competitive manner, on the other hand, naringenin was found to inhibit EROD activity in a non-competitive manner. Inhibition constant (Ki) values of quercetin, resveratrol, naringenin, hesperidin and rutin were calculated from Dixon plots as 0.12 µ
M, 0.67 µ
M, 2.63 µ
M, 18 µ
M and 0.1 mM, respectively. In the case of GST enzyme, it was demonstrated that all of the phenolic compounds/flavonoids used, exert an inhibitory effect on both total GST and GST-Mu activities of fish. Of the flavonoids tested, the most effective inhibitor of total GST activity was found to be resveratrol. The potency of the phenolic compounds/flavonoids to inhibit total GST activity follow the sequence of resveratrol >
quercetin >
rutin >
naringenin >
hesperidin with IC50 values of 7.1 µ
M, 24.5 µ
M, 89 µ
M, 116 µ
M and 118 µ
M respectively. Resveratrol, quercetin and hesperidin were found to inhibit total GST activity in a competitive manner, on the other hand, rutin and naringenin were found to inhibit GST activity in a mixed type manner. Ki values of resveratrol, quercetin, hesperidin, naringenin and rutin were calculated from Dixon plots as 3.2 µ
M, 12.5 µ
M, 45 µ
M, 128 µ
M and 150 µ
M respectively. In the case of GST-Mu activity, the most potent inhibitor was found to be rutin. The potency of the phenolic compounds/flavonoids to inhibit GST-Mu activity follow the sequence of rutin >
resveratrol >
quercetin >
naringenin >
hesperidin with IC50 values of 66.5 µ
M, 72.3 µ
M, 113.5 µ
M, 135.5 µ
M and 196 µ
M, respectively. In conclusion, this study indicated that flavonoids were the strong inhibitors of CYP1A1 associated EROD activity and GST activities of mullet liver. The modulation of drug-metabolizing enzymes by flavonoids is important in terms of human health, since these enzymes can activate or inactivate carcinogens. The potential role of xenobiotic metabolizers CYP1 family in the activation of carcinogens and inactivation of chemotherapeutics suggests a potential therapeutic benefits in inhibiting these enzymes. The results of the present study support the hypothesis that flavonoids may be involved in the prevention of malignant transformation, by reducing the formation of carcinogens through inhibition of enzymes such as CYP1A1 which is known to be involved in carcinogen activation.

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38

White, Natalie. "Optimization of Expression and Purification Methods for the Study of Protein-Based Magnetic Resonance Imaging Contrast Agents". Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/chemistry_theses/42.

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Magnetic Resonance Imaging instruments rely on a contrast agent to provide high-resolution images of tissues in vivo. However, current clinical contrast agents are hindered by low relaxivity and fast correlation time, necessitating high injection dosages. These concerns, among others, have driven the development of a class of protein-based contrast agents (ProCAs), by design of lanthanide binding sites into a scaffold protein. ProCA1 has a higher reported relaxivity and dosage efficiency than current contrast agents. In this study, expression and Glutathione-S-Transferase purification procedures were optimized, and a refolding method for rapid production of ProCA1 has been developed to enable studies of conformation, metal binding, relaxivity, and in vivo applications. Several ProCA1 variants with 4-5 charged ligand residues were shown to have strong gadolinium binding affinity (Kd of 10-12 M) and metal selectivity. Several options to improve ProCA1 have been explored, including addition of a polyethylene chain or a bombesin tag.

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39

Barrett, J., A. Dawber, B. Klugman, I. Obery, J. Shindler e J. Yawitch. "Vukani Makhosikazi South African Women Speak". Catholic Institute for International Relations, 1985. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000713.

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On 9 August 1984, African, White, Coloured and Indian women took to the streets of Johannesburg. They held placards saying,"Women unite against Botha's new deals, and Our sons won't defend apartheid, "You have struck a rock, you have touched the women, GST is killing us. The women were saying - these are our problems. They are caused by apartheid and the system of racial and economic exploitation in South Africa. Why do these problems exist in South Africa and where did they come from? In this book we try to give answers. In their own words, African women talk about their lives. They speak of their families, their jobs, their joys and hardships.

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Hoarau, Charles Pascal. "Etude des isoformes de GST chez deux mollusques marins Ruditapes decussatus et Mytilus galloprovincialis : Application à la surveillance de l'environnement". Aix-Marseille 2, 2002. http://www.theses.fr/2002AIX22040.

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41

Moura, Katia Franco Quaresma de [UNIFESP]. "Análise do polimorfismo de interleucina 6, GST e do gene dos receptores de progesterona relacionados à osteoporose após a menopausa". Universidade Federal de São Paulo (UNIFESP), 2006. http://repositorio.unifesp.br/handle/11600/39353.

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Objetivo: Avaliar alguns fatores genéticos relacionados ao desenvolvimento de osteoporose na pós-menopausa. Casuística e Métodos: Foram avaliadas 110 mulheres , nos primeiros cinco anos após a menopausa, sem uso de terapia hormonal prévia. O grupo foi analisado quanto à presença de polimorfismo de interleucina 6, GSTM1 do gene do receptor de progesterona, denominado PROGINS. Os dados clínicos foram registrados por meio de entrevistas com as pacientes. Avaliou-se a densitometria óssea de todas as pacientes, feita em aparelho Lunar para análise da densidade mineral óssea e do T escore em coluna lombar (L2-L4). As genotipagens de interleucina 6, GSTM1 e PROGINS foram realizadas pela reação em cadeia da polimerase (PCR) com DNA proveniente de raspado bucal. Utilizou-se, para análise estatística, o teste não paramétrico de Mann-Whitney ou o teste t de Student, a depender da variável estudada. Para cálculo da razão de chances, ou odds ratio (OR), para a ocorrência da doença, aplicou-se modelo de regressão logística. O nível de significância adotado foi de 5% (p < 0,05) e o intervalo de confiança foi de 95% (95% IC). Resultados: A idade média foi de 51,96 anos. Em relação ao polimorfismo de IL6, 58,2% das pacientes eram homozigotas (GG) e 41,8% apresentaram a presença do alelo C (heterozigoto ou GC + homozigoto mutante ou CC). Quanto ao genótipo PROGINS, 58,2% eram negativas (homozigoto selvagem ou P1/P1) e 41,8% eram positivas (heterozigoto ou P1/P2). No que tange ao polimorfismo GSTM1, 72,7% das pacientes mostraram a presença do alelo (1/1) e 27,3% ausência. Conclusão: O polimorfismo do gene da IL-6 correlacionou-se com baixa densidade óssea, ao passo que o polimorfismo PROGINS e do gene GSTM1 não se relacionaram com a densidade mineral óssea.
Objective: Evaluate the relation of genetic factors to the development of osteoporosis in post menopause. Methods: One hundred and ten women were evaluated in their first three post menopause years without the use of hormone therapy. The group was investigated for the presence of Interleucin 6 polymorphism, GSTM1 and the presence of a polymorfism of the progesterone receptor gene, PROGINS. The clinical data were obtained through pacient interviews and the genotypes were analyzed through polimerase chain (PCR) with DNA from mouth raspado. The statistical analysis used the Mann-Whitney nonparametric test or the T-Student test, depending on the tested variable. The Logistical Regression model was used to obtain the odds ratio for the disease. The significance level adopted was 5% and the confidence interval was 95%. Results: Average age was 51.96 years. 58.2% of patients were homozygous (GG) for the IL6 polymorphism and 41.8% presented the C alelus. 58.2% were negative negative PROGINS genotype and 41.8% were positive. 72.7% presented the alelus (1/1) for polymorphism GSTM1 and 27.3% did not. Conclusion: The IL6 gene polymorphism correlated with low bone mass, while PROGINS and GSTM1 polymorphisms did not.

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42

Farias, Luciana Fortes. "SISTEMA MULTIAGENTE PARA MONITORAMENTO AMBIENTAL DO COMPLEXO PORTUÁRIO DA ILHA DE SÃO LUÍS-MARANHÃO". Universidade Federal do Maranhão, 2009. http://tedebc.ufma.br:8080/jspui/handle/tede/423.

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This work is discussed the conceptual model of a multi-agent system for environmental monitoring with the use of biomarkers of aquatic organisms present in the port complex of São Luís-Maranhão-Brasil, second most important in the country in cargo handling. Located in the São Marcos Bay, this complex have an estuarine ecosystems which have suffered attacks in the current process of economic development, caused by intense port handling, dumping of ballast water and washing the vessels, overfishing, introduction of exotic species in the middle pollution in urban and industrial effluents, subject to severe environmental impacts that should be monitored. Methodologically, the modeling of the monitoring solution, we used the existing environmental conditions and aquatic life caught in two different sites of the port complex, the first in a potentially contaminated area and the second in a contamination-free (control), proposing the creation of a network of sensors in these locations. Invest conceded data by Carvalho-Neta (2007) whose research includes to catch fish in these perimeters, then submitting them for laboratory analysis to measure the enzyme activity of glutathione S-transferase (GST) and Catalase (CAT), the result was processed and recorded in bio-ontology . The core of the solution of Multi-agent system is based on the results derived from the biochemical analysis of GST, inspiring the modeling software agent that simulates the behavior of this enzyme. The solution also includes an application running on mobile devices that makes the collection of environmental variables in the selected points, validates them and makes the inference of those who could not be collected. Multi-agent System for Environmental Monitoring of the Port Complex of the Island of São Luís-Maranhão- Brasil, therefore, is made up of the bio-ontology, sensor networking, mobile application collection and inference of data from environmental conditions, software agents to simulate biochemical analysis, calculation of GST activity and other staff related to the maintenance and security of the SMA.
Nesta dissertação é discutido o modelo conceitual de um sistema multiagente para monitoramento ambiental com uso de marcadores biológicos de organismos aquáticos presentes no complexo portuário de São Luís-MA, segundo mais importante do país em movimentação de carga. Situado na Baía de São Marcos, esse complexo possui um dos ecossistemas estuarinos que mais têm sofrido agressões no atual processo de desenvolvimento econômico, provocadas pela intensa movimentação portuária, despejo de água de lastro e lavagem dos navios, pesca predatória, introdução de espécies exóticas no meio, poluição por efluentes domésticos e industriais, sujeitando o ambiente a fortes impactos ambientais que devem ser monitorados. Metodologicamente, na modelagem da solução de monitoramento, utilizou-se o registro das condições ambientais e de organismos aquáticos capturados em dois pontos distintos do complexo portuário: o primeiro, em uma área potencialmente contaminada e o segundo em uma livre de contaminação (controle), propondo-se a criação de uma rede de sensores nesses locais. Empregou-se dados cedidos por Carvalho-Neta (2007) cuja pesquisa contou com a captura de peixes nesses perímetros, submetendo-os posteriormente a análise laboratorial para medição da atividade enzimática da Glutationa s- Transferase (GST) e Catalase (CAT), tendo todos os resultados processados e registrados em bio-ontologia. O núcleo da solução do Sistema Multiagente baseia-se nos resultados oriundos da análise bioquímica da GST, inspirando a modelagem de agente de software que simula o comportamento desta enzima. Todos esses dados foram registrados em bio-ontologia. A solução contempla também uma aplicação executada em dispositivos móveis que realiza a coleta das variáveis abióticas nos pontos selecionados, valida-as e realiza a inferência daquelas que não puderam ser coletadas. O Sistema Multiagente para Monitoramento Ambiental do Complexo Portuário da Ilha de São Luís, portanto, é constituído pelo conjunto da bio-ontologia, rede de sensores, aplicação móvel de coleta e inferência de dados das condições do meio ambiente, agentes de software para simulação de análise bioquímica, cálculo da atividade da GST e outros agentes relacionados à manutenção e segurança do SMA.

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Choi, Yook-Wah. "Structural and functional characterization of human DDX5 and its interaction with NS5B of hepatitis C virus". University of the Western Cape, 2011. http://hdl.handle.net/11394/5299.

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Philosophiae Doctor - PhD
Hepatitis C was first recognized as a transfusion-associated liver disease not caused by hepatitis A or hepatitis B virus after serological tests were developed to screen for their presence in the blood. The infectious agent was finally identified with the cloning of the cDNA of hepatitis C virus (HCV) using random polymerase chain reaction (PCR) screening of nucleic acids extracted from plasma of a large pool of chimpanzee infected with non-A non-B hepatitis. NS5B, a membrane-associated RNA-dependent RNA polymerase essential in the replication of HCV, initiates the synthesis of a complementary negative-strand RNA from the genomic positive-strand RNA so that more positive-strand HCV RNA can then be generated from the newly synthesised negative-strand template. The crystal structure of NS5B presented typical fingers, palm and thumb sub-domains encircling the GDD active site, which is also seen in other RNA-dependent RNA polymerases, and is similar to the structure of reverse transcriptase of HIV-1 and murine Moloney leukaemia virus. The last 21 amino acids in the C-terminus of NS5B anchor the protein to the endoplasmic reticulum (ER)-derived membranous web. NS5B has been shown to interact with the core, NS3/NS4A, NS4B and NS5A proteins, either directly or indirectly. Numerous interactions with cellular proteins have also been reported. These proteins are mainly associated with genome replication, vesicular transport, protein kinase C-related kinase 2, P68 (DDX5), α-actinin, nucleolin, human eukaryotic initiation factor 4AII, and human VAMP-associated protein. Previous studies have confirmed that NS5B binds to full-length DDX5. By constructing deletion mutants of DDX5, we proceeded to characterize this interaction between DDX5 and HCV NS5B. We report here the identification of two exclusive HCV NS5B binding sites in DDX5, one in the N-terminal region of amino acids 1 to 384 and the other in the C-terminal region of amino acids 387 to 614. Proteins spanning different regions of DDX5 were expressed and purified for crystallization trials. The N-terminal region of DDX5 from amino acids 1 to 305 which contains the conserved domain I of the DEAD-box helicase was also cloned and expressed in Escherichia coli. The cloning, expression, purification and crystallization conditions are presented in this work. Subsequently, the crystal structure of DDX5 1-305 was solved and the high resolution three-dimensional structure shows that in front of domain I is the highly variable and disordered N terminal region (NTR) of which amino acids 51-78 is observable, but whose function is unknown. This region forms an extensive loop and supplements the core with an additional α-helix. Co-immunoprecipitation experiments demonstrated that the NTR of DDX5 1-305 auto-inhibit its interaction with NS5B. Interestingly, the α-helix in NTR is essential for this auto-inhibition and seems to mediate the interaction between the highly flexible 1-60 residues in NTR and NS5B binding site in DDX5 1-305, presumably located within residues 79-305. Furthermore, co-immunoprecipitation experiments revealed that DDX5 can also interact with other HCV proteins, besides NS5B.

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44

Flamant, Cyril. "Mucoviscidose et système oxydant / anti-oxydant : étude de gènes modificateurs". Paris 6, 2005. http://www.theses.fr/2005PA066297.

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Carmo, Lílian Pires de Freitas do. "Avaliação da performance dos biomarcadores e da bioquímica urinária no diagnóstico de injúria renal aguda em pacientes críticos: coorte prospectiva". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5148/tde-06122016-104121/.

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Introdução: Injúria Renal Aguda (IRA) é uma patologia grave e com elevada incidência em pacientes críticos. Apesar do avanço no conhecimento fisiopatológico ocorrido nas últimas décadas, pouco desse conhecimento foi traduzido em terapia para IRA já instalada. Medidas preventivas para evitar a progressão da IRA em momentos iniciais da injúria continuam a ser o principal foco na terapia da IRA. Nesse contexto, o diagnóstico e determinação precoce da gravidade da injúria renal são fundamentais para evitar a progressão para estágios mais graves e diminuir a morbidade e a mortalidade associadas à síndrome. Objetivos: O objetivo principal deste estudo, foi avaliar se o padrão de elevação dos biomarcadores permite a detecção precoce do diagnóstico de IRA. E os objetivos secundários foram avaliar se os biomarcadores podem auxiliar na predição da gravidade da IRA, na necessidade de diálise e óbito. Métodos: Estudo prospectivo, unicêntrico, entre janeiro de 2012 e janeiro de 2015. Foram avaliados e incluídos pacientes com critérios de alto risco para IRA nas Unidades de Terapia Intensiva (UTI) clínicas e cirúrgicas. Características clínicas e demográficas foram avaliadas no início da internação e a evolução laboratorial e hemodinâmica dos pacientes foram acompanhadas durante as primeiras 48 horas de internação na UTI. Os biomarcadores precoces de injuria renal aguda séricos e urinários, assim como a bioquímica e microscopia urinária, foram analisados a cada 12 horas durante este período. IRA foi definida pelo critério da creatinina do KDIGO. Episódios de IRA com resolução em 3 dias foram definidos como transitória (IRAt) e episódios com duração maior que 3 dias como persistente (IRAp). Resultados: Durante o período estudado foram avaliados 376 pacientes, dos quais 70 preencheram os critérios de inclusão e 32 (46%) evoluiram com IRA. Noventa porcento dos pacientes incluídos no estudo foram pacientes em pós-operatorio. Não houve diferença nas características basais entre os grupos com IRA e sem IRA. A fração de excreção de sódio (FENa) foi maior no grupo com IRAp à admissão, entretanto foi menor que 1% em todos os grupos. O gradiente transtubular de potássio (TTKG) foi significativamente maior no 4º e 5º momentos no grupo com IRAp quando comparado aos outros grupos. Os níveis de Neutrophil Gelatinase-Associated Lipocalin (NGAL), tanto séricos como urinários foram significativamente maiores no grupo com IRAp em relação ao grupo IRAt e não IRA, assim como Liver-type Fatty Acid-Binding Protein (L-FABP) e o Kidney Injury Molecule-1 (KIM-1). Não se constatou diferença significativa entre os grupos em relação ao Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), alfa e pi-Glutathione-transferase (alfa- GST e pi-GST). Entre os pacientes com diagnóstico de IRA pela creatinina sérica nos primeiros 2 dias de UTI, o emprego do NGAL sérico e/ou urinário possibilitaram o diagnóstico mais precoce da IRA em relação à creatinina em 59,3 % e 27,6% dos pacientes, respectivamente. O NGAL sérico e urinário foram preditores independentes de mortalidade e de necessidade de terapia de substituição renal à análise multivariada. Conclusão: Na IRA persistente a bioquímica urinária apresentou diferenças em relação à FENa e ao TTKG. A performance do NGAL sérico e urinário nesta população conseguiu antecipar o diagnóstico da IRA em relação ao critério da creatinina. O NGAL sérico e urinário foram preditores independentes de necessidade de terapia de substituição renal e mortalidade
Background: Acute kidney injury (AKI) is a syndrome with high incidence in critical ill patients and associated with severe complications. Although important advances has been achieved in the understanding of its physiopathology, this knowledge have not resulted in improvements in therapy for AKI. Preventive measures to avoid AKI progress at the initial phases of injury are still the main goal of AKI therapy. Therefore, early diagnosis and assessment of disease severity are essential to prevent disease progression and to reduce morbidity and mortality. Objectives: The main goal of this study was to evaluate whether a panel of biomarkers would allow early detection of AKI. Secondary endpoints were to evaluate whether biomarkers can predict the severity of AKI, need for dialysis and mortality in high-risk critical ill patients. Methods: We performed a prospective study between January 2012 and 2015. We recruited patients admitted in intensive care unit (ICU) with high risk for AKI. Clinical and demographic characteristics were recorded. Urinary biomarkers and urine biochemistry were measured sequentially every 12 hours during the first two days of ICU stay. AKI was defined according to KDIGO creatinine criteria. Patients were classified as having transitory AKI (tAKI) or persistent AKI (pAKI). Results: Of the 376 patients initially evaluated, 70 met the inclusion criteria. Thirty-two patients (46 %) met KDIGO criteria for AKI. Ninety percent of the patients in this study were surgical. The baseline characteristics were similar among all groups. The fractional excretion of sodium (FENa) was higher in pAKI group, and it was < 1% in all groups. In patients who developed pAKI the transtubular potassium gradient (TTKG) was significantly higher at 36h and 48h. Plasma and urinary Neutrophil Gelatinase-Associated Lipocalin (NGAL), Liver-type Fatty Acid-Binding Protein (L-FABP) and Kidney Injury Molecule-1 (KIM-1) were significantly higher in the pAKI group as compared to the t AKI and non AKI groups in different times of evaluation. There was no difference in levels of Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), alfa and pi-Glutathione-transferase (alfa-GST and pi-GST) within the groups during the first 48 h of ICU admission. Based on the cutoff levels, plasma and urinary NGAL would determine earlier diagnosis in 59.3% and 27.6% patients in the first two days of ICU, respectively. In the multivariate analysis, plasma and urinary NGAL were independent predictors of need for dialysis and mortality. Conclusions: In this study population, persistent AKI have alterations in urinary physicochemical parameters such as FENa and TTKG. Plasma and urinary NGAL were early biomarkers for AKI diagnosis. Plasma and urinary NGAL were independent predictors of dialysis and mortality

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Forestiero, Francisco José. "Variantes genéticas da N-acetiltransferase 2, CYP2E1 e glutationa S-transferase: relação com a segurança terapêutica em pacientes com tuberculose". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-05072009-180443/.

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Polimorfismos nos genes da n-acetiltransferase 2 (NAT2), CYP2E1 e glutationa S-transferase (GST) têm sido associados a diferenças na resposta ao tratamento da tuberculose. O papel de variantes dos genes NAT2, CYP2E1 e GSTM1/GSTT1, no perfil de segurança do tratamento da tuberculose, foi avaliado em 99 pacientes com tuberculose, sem co-infecção por HIV ou vírus da hepatite, tratados por 6 meses. Amostras de sangue foram colhidas antes e durante o tratamento para avaliação de marcadores de lesão hepatocelular (ASLT e AST), colestase (ALP, GGT e bilirrubinas) e função renal (creatinina). O DNA genômico foi extraído de sangue colhido em EDTA pelo método precipitação salina. Os polimorfismos NAT2 foram analisados por PCR-RFLP e seqüenciamento de DNA. Os polimorfismos da região promotora do CYP2E1 foram detectados por PCR-RFLP e para a análise dos genótipos nulos de GSTM1 (GSTM1*0) e GSTT1 (GSTT1*0) foi utilizada a PCR multiplex. Durante o tratamento, 59,6% dos pacientes apresentaram reações adversas aos medicamentos (RAM) e alterações nos marcadores de lesão hepatocelular e colestase, com aumento de 1 a 4 vezes o limite superior de referência. Foi observada forte relação entre RAM e alterações nos marcadores séricos (p< 0,05) e também com o uso de medicação concomitante (p< 0,001). As freqüências dos alelos NAT2*4 e NAT2*6 foram maiores e menores, respectivamente, quando comparadas com outros estudos na população brasileira. O perfil de acetilador lento (alelos NAT2*5, NAT2*6 e NAT2*7) foi associado com manifestação de RAM e hepatotoxicidade. Os portadores dos genótipos NAT2*4/*5 e NAT2*5/*5 apresentaram, respectivamente, risco 2,4 e 5,0 vezes maior de RAM que os portadores dos demais genótipos NAT2 (p< 0,05). O genótipo funcional GSTM1*1/GSTT1*1 foi associado com alterações acentuadas de ALT, AST e ALP (p< 0,05). Enquanto que as variantes da CYP2E1 não foram associadas a alterações no perfil bioquímico ou com risco de RAM ou hepatotoxicidade. Em conclusão, o perfil de acetilação lenta de NAT2 e o genótipo funcional de GSTM1/GSTT1 aumentam a susceptibilidade de lesão hepatocelular e outras RAM induzidas pelos antimicobacterianos utilizados no tratamento da tuberculose.
Polymorphisms in N-acetiltransferase 2 (NAT2), CYP2E1 and glutatione S-transferase (GST) have been associated with differences in response to antituberculosis drugs. The role of the NAT2, CYP2E1 and GSTM1/GSTT1 variants on safety profile of the anti-tuberculosis therapy was evaluated in 99 tuberculosis patients, without co-infection by HIV or hepatitis virus, treated during 6 months. Blood samples were collected before and after the therapy to evaluate serum markers for hepatocelullar damage (ASLT and AST), cholestasis (ALP, GGT and bilirrubin) and kidney function (creatinine). Genomic DNA was extracted from EDTA-blood samples by salting-out method. NAT2 polymorphisms were analyzed by PCR-RFLP and DNA sequencing. CYP2E1 promoter region polymorphisms were detected by PCR-RFLP and for analysis of the null genotypes GSTM1 (GSTM1*0) e GSTT1 (GSTT1*0) PCR multiplex technique was used. During the therapy, 59.6% of the patients had adverse drug reactions (ADR) and alterations on hepatocellular damage and cholestasis serum markers, with increase of 1 to 4 times the upper limit reference level. There was a significant relationship between ADR and serum markers alterations (p< 0,05), as well as, the concomitant medicine (p< 0,001). The frequencies of the NAT2*4 and NAT2*6 alleles were higher and lower, respectively, when compared to other studies in the Brazilian population. The slow acetilator profile (NAT2*5, NAT2*6 and NAT2*7 alleles) was associated with ADR and hepatotoxicity manifestations. The NAT2*4/*5 and NAT2*5/*5 genotypes carriers had, respectively, 2.4 and 5.0 times higher risk for ADR than those carrying the other NAT2 genotypes (p< 0,05). The functional genotype GSTM1*1/GSTT1*1 was associated with enhanced variations on ALT, AST and ALP (p< 0.05). No relationship was found between CYP2E1 variants and variations on biochemical profile or risk for ADR or hepatotoxicity. In conclusion, the NAT2 slow acetilator profile and the GSTM1/GSTT1 functional genotype increase the susceptibility to hepatocellular damage and other ADR induced by antibiotics used in tuberculosis therapy.

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Carvalho, Graciana Souza Lordelo de. "Polimorfismo nos genes MTHFR, Glutationa S-transferase (GST) e Haptoglobina (HP) e sua relação na ocorrência da Leucemia Mielóide Crônica (LMC)". reponame:Repositório Institucional da UnB, 2011. http://repositorio.unb.br/handle/10482/9615.

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Dissertação (mestrado)-Universidade de Brasília, Programa de Pós-Graduação em Patologia Molecular, 2011.
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A leucemia mielóide crônica é uma doença de células hematopoiéticas na qual ocorre a proliferação celular descontrolada dos leucócitos. Embora os aspectos clínicos e biológicos estejam bem documentados, pouco se sabe sobre a susceptibilidade individual à doença. Neste trabalho foi realizado um estudo caso-controle analisando a prevalência dos polimorfismos MTHFR C6777T e A1298C, GSTM1, GSTT1 e haptoglobina em 105 pacientes com leucemia mielóide crônica (LMC) e em 273 controles saudáveis, por meio das técnicas de reação em cadeia da polimerase (PCR), seguida ou não por digestão com enzimas de restrição (RFLP). Uma associação com risco de desenvolver LMC foi encontrada para os genótipos MTHFR 1298AA (OR = 1,794 IC 95% = 1,14-2,83) e GSTM1 não nulo (OR = 1,649; IC 95% = 1,05-2,6; p = 0,031), enquanto os genótipos MTHFR 1298AC (OR = 0,630; IC 95% = 0,40-0,99, p=0,047) e GSTM1 nulo (OR = 0,606; IC 95% = 0,21-0,77, p = 0,031) diminuiram este risco. Verificou-se para o genótipo MTHFR 1298AA, um aumento do risco para o sexo feminino (OR=2,052; 95% CI=1,08-3,92; p=0,028), como também para faixa etária de 20-40 anos (OR=1,980; 95% CI=1,06-4,65; p=0,047) e para indivíduos de pele branca (OR=2,218; 95% CI=1,09-4,51; p=0,026). Em relação a GSTM1, o aumento do risco foi também associado ao sexo feminino (OR=2,505; 95% CI=0,21-0,77; p=0,031) e para indivíduos >60 anos (OR=6,222; 95% CI=1,63-23,76; p=0,006). Indivíduos Hp1F-1S de pele negra também apresentaram aumento do risco (OR=7,200; 95% CI=0,94-54,94; p=0,037).A diminuição do risco anteriormente apresentada para MTHFR 1298AC e GSTM1 nulo foram também relacionados ao sexo feminino, para MTHFR (OR=0,520; 95% CI=0,27-0,99; p=0,046) e para GSTM1 (OR=0,399; 95% CI=0,21-0,77; p=0,005). Também se observou para GSTM1 nulo, a diminuição do risco para >60 anos (OR=0,161; 95% CI=0,04-0,61; p=0,006). Uma diminuição do risco para indivíduos de pele negra foi observada para o genótipo Hp1S-2 da haptoglobina (OR=0,619; 95% CI=0,44-0,87; p=0,011). Uma diminuição do risco no sexo masculino ocorreu apenas para o genótipo MTHFR 677CC (OR=0,495; 95% CI=0,26-0,95; p=0,032).Os resultados indicaram também a seleção a favor dos heterozigotos para o loco MTHFR 1298. A variabilidade em populações humanas pode refletir, em parte, processos distintos de seleção natural e adaptação às condições ambientais variáveis. A população brasileira é muito heterogênea e miscigenada, e nossos resultados indicaram que, pelo menos para esta população, esses dois polimorfismos são importantes no contexto da LMC, necessitando de maiores investigações em associação com dosagens de folato e dados clínicos. _______________________________________________________________________________ ABSTRACT
Chronic myeloid leukaemia is a haematopoietic stem cell disorder causing uncontrolled cell proliferation of white blood cells. Although these clinical and biological aspects are well documented, little is known about individual susceptibility to the disease. We conducted a case-control study analysing the prevalence of the polymorphisms MTHFR C6777T, MTHFR A1298C,GSTM1, GSTT1 and Haptoglobin in 105 patients with chronic myeloid leukaemia (CML) and 273 healthy controls, using polymerase chain reaction (PCR)-based methods. An association with risk of developing CML was found for MTHFR 1298AA (OR= 1.794; 95% CI= 1.14−2.83) and GSTM1 non-null (OR= 1.649; 95% CI= 1.05−2.6; p=0.031) genotypes, while MTHFR 1298AC (OR= 0.630; 95% CI= 0.40−0.99; p=0.047) and GSTM1 null (OR= 0.606; 95% CI= 0.21−0.77; p=0.031) genotypes decreased this risk. For MTHFR 1298AA, this risk was particularly related to females (OR= 2.052; 95% CI= 1.08-3.92; p=0.028), age group of 20-40 years (OR= 1.980; 95% CI= 1.06-4.65; p=0.047) and white skin colour (OR= 2.218; 95% CI= 1.094.51; p=0.026); for GSTM1, it was related to females (OR=2.505; 95% CI= 0.210.77; p=0.031) and the age group >60 years (OR= 6.222; 95%CI= 1.63-23.76; p=0.006). Results also showed an increased risk for individuals of black skin colour carrying Hp1F-1S genotype, despite the small sample size and the large confidence interval (OR= 7.200; 95% CI= 0.94-54.94; p=0.037). A decreased CML risk was observed for the genotypes MTHFR 1298AC (OR= 0.630; 95% CI= 0.40-0.99; p=0.047) and GSTM1 null (OR= 0.606; 95% CI= 0.21-0.77; p=0.031), and both were also related to females (OR= 0.520; 95% CI= 0.27-0.99; p=0.046 for MTHFR; and OR= 0.399; 95% CI= 0.21-0.77; p=0.005 for GSTM1). For GSTM1 null genotype, it was also related to the age group >60 years (OR= 0.161; 95% CI=0.04-0.61; p=0.006). For males, a decreased risk was observed only for MTHFR 677CC genotype (OR= 0.495; 95% CI= 0.26-0.95; p=0.032). A decreased risk was also observed for individuals of black skin colour carrying Hp1S-2 genotype (OR= 0.619; 95% CI= 0.44-0.87; p=0.011). For males, a decreased risk was observed only for MTHFR 677CC genotype (OR= 0.495; 95% CI= 0.26-0.95; p=0.032).Results also indicated selection in favour of heterozygous for MTHFR 1298 loco. The considerable range of variation in human populations may reflect, in part, distinctive processes of natural selection and adaptation to variable environmental conditions. The Brazilian population is very mixed and heterogeneous, and our results indicated that, at least for this population, these two locus are important in the context of CML, needing further investigation in association with folate dosages and clinical data.

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Ivanoff, Nathalie. "Liposomes multilamellaires vecteurs de l'antigene rsm28 gst (schistosoma mansoni 28 kda glutathion s-transferase recombinante ) pour une vaccination par voie muqueuse". Lille 2, 1996. http://www.theses.fr/1996LIL2T008.

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49

Nascimento, Thaylla Horbylon. "Clonagem, expressão heteróloga e interações intermoleculares da proteína aspartato semialdeído desidrogenase de Paracoccidioides brasiliensis". Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/9114.

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Outro
Paracoccidioides comprises the genus of fungi causing paracoccidioidomycosis. The research of new treatments, especially those based on inhibition of metabolic pathways important for microorganisms has gained prominence and the aspartate pathway, necessary for the biosynthesis of threonine, isoleucine and methionine in microorganisms, is not found in humans. Catalyzing the second step of this pathway, we found aspartate semialdehyde dehydrogenase (ASADH), which has not yet been characterized in Paracoccidioides spp. and has no substituents in its catalytic function in the aspartate pathway. Thus, it is of interest the determination of its biological properties experimentally that their biological properties be determined experimentally. ASADH from Pb18 was cloned into vector pGEX-4T3, expressed in E. coli Stellar cells and purified on a glutathione-sepharose column. Then, antibodies were produced and used in Western blot assay to confirm protein expression. The pull-down-GST assay was performed and allowed the identification of complexes of interactions between ASADH and soluble proteins present in total protein extract of the yeast form of Pb18. Interactions with proteins of several functional categories, among them those related to the metabolism of threonine, isoleucine and methionine, were found, reinforcing the performance of ASADH in the amino acid biosynthesis of Pb18, as well as proteins related to substrate supply to the aspartate pathway and proteins that use metabolites of this pathway. Interactions with proteins involved in other metabolic pathways were also observed, as well as unprecedented interactions, suggesting the importance of ASADH in the functional processes of microorganisms.
Paracoccidioides compreende o gênero de fungos causadores da paracoccidioidomicose. A pesquisa de novos tratamentos, sobretudo aqueles baseados em inibição de vias metabólicas importantes para micro-organismos, tem ganhado destaque e a via do aspartato não é encontrada em humanos. A via do aspartato é necessária para a síntese de treonina, isoleucina e metionina. Catalisando o segundo passo dessa via, encontramos a aspartato semialdeído desidrogenase (ASADH), que ainda não foi caracterizada em Paracoccidioides spp. e não possui substituintes em sua função catalítica na via do aspartato. Assim, é de interesse que suas propriedades biológicas sejam determinadas experimentalmente. A ASADH proveniente de Pb18 foi clonada em vetor pGEX-4T3, expressa em células E. coli Stellar e purificada em coluna de glutationa-sefarose. Em seguida, anticorpos foram produzidos e utilizados em ensaio de Western-blot para confirmar a expressão proteica. O ensaio de pull-down-GST foi realizado e permitiu a identificação de complexos de interações entre a ASADH e proteínas solúveis presentes em extrato proteico total da forma de levedura de Pb18. Foram encontradas interações com proteínas de diversas categorias funcionais, dentre elas relacionadas ao metabolismo de treonina, isoleucina e metionina, reforçando a atuação da ASADH na biossíntese de aminoácidos de Pb18, bem como proteínas relacionadas ao fornecimento de substrato para a via do aspartato e proteínas que utilizam os metabólitos dessa via. Também foram observadas interações com proteínas envolvidas em outras vias metabólicas, assim como interações inéditas, sugerindo a importância de ASADH nos processos funcionais de micro-organismos.

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De, Pol Riccardo <1978&gt. "Inquinamento da metalli pesanti in relazione ai processi metabolici: importanza delle metodiche di speciazione". Doctoral thesis, Università Ca' Foscari Venezia, 2010. http://hdl.handle.net/10579/991.

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Sono state considerate le concentrazioni dei metalli pesanti in genere ed in particolare delle specie organiche ed inorganiche dell’arsenico in bioti, Mytilus galloprovincialis e Tapes philippinarum, campionati in siti a differente inquinamento nelle Lagune di Venezia e Grado-Marano. I risultati sono stati valutati assieme all’ambiente di vita (stato ecologico), alla relazionata disponibilità di cibo, allo stato di salute dei bioti, all’attività dell’enzima glutathione S-transferase (GST), alla dimensione delle branchie, ghiandole e resto del corpo, alla capacità filtrante ed all’idrodinamica dei siti di campionamento. Maggiore efficienza metabolica, maggiori concentrazioni di arsenobetaina (considerata non tossica) e maggiore attività delle GST sono state riscontrate in bioti campionati nelle zone meno inquinate. Le concentrazioni e la relativa abbondanza delle specie dell’arsenico nei bioti sono state quindi collegate a qualità ambientale, biodiversità e correlata attività degli enzimi di detossificazione, sottolineando l’importanza delle metodiche di speciazione per la corretta interpretazione dei dati.
In this study we analyzed organic and inorganic arsenic species in mussels, Mytilus galloprovincialis and Tapes philippinarum, collected in sites of the Venice and Marano Lagoons of different pollution levels. The obtained values were considered together with the life environment and health state of the mussels, the glutathione S-transferase (GST) activity, the size of gills, glands, and the rest of the body, the food abundance and variety. Furthermore, we considered the filtering capacity, the hydrodynamics of the various sampling sites and the environmental quality in general. Higher metabolic efficiency, higher percentages of arsenobetaine (considered non-toxic) and higher GST activity were found in mussels sampled at sites with low pollution. In conclusion, our results support the view that the concentrations and relative abundance of arsenic species in mussels are related to environmental quality, biodiversity and the detoxification enzyme activities in mussels underlining the importance of speciation methods to understand results.

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