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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Isolation, characterization and adhesion performance of sorghum, canola and camelina proteins

Li, Ningbo January 1900 (has links)
Doctor of Philosophy / Department of Biological and Agricultural Engineering / Donghai Wang / Sorghum distillers dried grains with solubles (DDGS), canola and camelina meals are the main co-products resulting from grain-based ethanol or oil production. The main objective of this research was to study physicochemical properties of proteins isolated from DDGS, canola and camelina meals and their adhesion performance. Acetic acid-extracted sorghum protein (PI) from DDGS had superior adhesion performance in terms of dry, wet and soak adhesion strength compared to acetic acid-extracted sorghum protein (PF) from sorghum flour and aqueous ethanol-extracted sorghum protein (PII) from DDGS. PI had a significantly higher wet strength (3.15 MPa) than PII (2.17 MPa), PF (2.59 MPa), and soy protein without modification (1.63 MPa). The high content of hydrophobic amino acids in PI (57%) was likely the key factor responsible for high water resistance. Canola protein was extracted from canola meal and modified with different concentrations of NaHSO3 (0 to 15 g/L) during protein isolation. Unmodified canola protein showed the highest wet shear strength of 3.97 MPa cured at 190 °C. Adhesion strength of canola protein fractions extracted at pH 5.5 and pH 3.5 (3.9-4.1 MPa) was higher than the fraction extracted at pH 7.0. NaHSO3 slightly weakened adhesion performance of canola protein; however, it improved handling and flow-ability due to breaking of disulfide bonds in proteins. Albumin, globulin, and glutelins were isolated from camelina meal. Adhesion performance of globulin fraction behaved better than glutelin fraction. The greatest wet shear strength of globulin was 3.3 MPa at curing a temperature of 190 °C. Glutelin had a more protein aggregation compared with globulin, as indicated by higher crystallinity and thermal stability, and dense protein aggregate. This compact structure of glutelins may partially contribute to lower adhesion strength as compared to globulin.
2

Heterologní exprese a izolace lidského cytochromu P450 1B1 / Heterologous expression and isolation of human cytochrome P450 1B1

Sojka, Pavel January 2015 (has links)
Cytochromes P450 are heme enzymes with very broad substrate specificity, they can oxidize tens to hundreds of different substrates including both eobiotics and xenobiotics, but with varying efficiencies and kinetics. They are responsible for the metabolic activation of many carcinogens resulting in formation of reactive intermediates, these reactive species participate in the formation of DNA adducts and also increase of oxidative stress. Eukaryotic cytochromes P450 are membrane bound enzymes found mostly in the endoplasmic reticulum. In vertebrates, they are expressed in a variety of tissues mostly in the liver, but also in kidney, lung, skin and others. The cytochrome P450 1B1 is an inducible enzyme which occurs mainly in the lung and skin. Its expression is induced predominantly by the presence of polycyclic aromatic hydrocarbons, dioxins and heterocyclic amines. The human cytochromes P450 are typically obtained using heterologous expression and isolated as a C-terminally modified hexa-histaq constructs using immobilized metal affinity chromatography. This thesis focuses on effect of C-terminal modifications on activity of human cytochrome P450 1B1. First, the two expression vectors encoding the human form of cytochrome P450 1B1 were prepared, one contained a classical C-terminal hexa-histaq...
3

Estudo da biodegradação da blenda poli (epsilon-caprolactona) / amido modificado/proteina isolada de soja em diferentes solos : caracterização dos produtos formados e avaliação da toxicidade

Mariani, Pilar Drummond Sampaio Correa 15 August 2018 (has links)
Orientadores: Lucia Helena Innocentini Mei, Elke Jurandy Bran Nogueira Cardoso / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-15T18:48:38Z (GMT). No. of bitstreams: 1 Mariani_PilarDrummondSampaioCorrea_D.pdf: 18147924 bytes, checksum: 325f49ef8840be70ed59254449097128 (MD5) Previous issue date: 2010 / Resumo: O desenvolvimento de polímeros biodegradáveis tem como objetivo contribuir com a redução do volume de lixo plástico descartado no meio ambiente. Em vista disso, a utilização de polímeros naturais na confecção de blendas tem proporcionado o aproveitamento de recursos de fontes renováveis como e o caso do amido e da soja. Nesse trabalho, dando continuidade as pesquisas realizadas anteriormente no grupo de materiais biodegradáveis da Profa. Lucia H. Innocentini-Mei (FEQ/UNICAMP),foram utilizadas blendas a base de poli (e-caprolactona), amido de milho modificado, proteína isolada de soja (PIS) e sorbitol. As blendas foram preparadas através de extrusão em extrusora mono-rosca e prensagem a quente e as amostras assim obtidas foram submetidas a caracterização e estudo da biodegradação em diferentes solos, com o apoio do Laboratório de Microbiologia do solo da ESALQ/USP, sob a supervisão da Profa. Elke J.B. Cardoso. A caracterização dos materiais obtidos deu enfoque as propriedades térmicas, mecânicas, morfológicas e capacidade de biodegradação em solos de diferentes texturas, e com ou sem a adição de N-fertilizante. Observou-se que a incorporação de amido modificado e proteína isolada de soja foram responsáveis pela redução das propriedades térmicas e mecânicas dos materiais, mas, para muitas aplicações estas propriedades não são requisitos indispensáveis. Com relação à proteína isolada de soja, esta proporcionou a redução da relação carbono/nitrogênio (C/N) da blenda como esperado, atributo que foi decisivo durante o processo de biodegradacao das formulacoes em diferentes solos. A mineralizacao das formulações foi maior em solo de textura arenosa, com maior conversão de carbono a dióxido de carbono (CO2); por outro lado, o solo de textura argilosa não apresentou taxas altas de conversão de carbono a dióxido de carbono para as blendas, mas foi mais eficiente na formação de biomassa microbiana, comparado ao solo arenoso. / Abstract: The development of biodegradable polymers came to reduce the volume of plastic waste discarded in the environment. As a result, the use of natural polymers in the manufacture of blends has provided the use of renewable resources such as starch and soy. In this work, continuing the research done previously in the biodegradable materials group of School of Chemical Engineering School at State University of Campinas/ Brazil, supervised by Prof. Lucia H. Innocentini-Mei, blends of poly (e-caprolactone)/modified starch, soy protein isolate (SPI) and sorbitol were prepared by extrusion in single-screw extruder and hot pressing machine. The samples obtained were subjected to characterization and study of biodegradation in different soils, with the support of the Laboratory of Soil Microbiology (ESALQ/USP), under the supervision of Professor Elke J. B. N. Cardoso. The characterization of the material has focused on thermal, mechanical and morphological properties, and also on the biodegradation capacity in soils of different textures, and with or without the addition of N-fertilizer. It was observed that the incorporation of modified starch and soy protein isolate were responsible for the reduction of thermal and mechanical properties of materials but, for many applications, these properties are not necessaries. With respect to soy protein isolate (SPI), it reduced the carbon / nitrogen (C/N) of the blend as expected, an attribute which was decisive in the process of biodegradation of the studied formulations in different soils. Mineralization of the formulations was higher in sandy soil, with the higher conversion of carbon to carbon dioxide (CO2) compared to the clay soil, which did not show high rates of conversion but was more efficient in the formation of microbial biomass. / Doutorado / Ciencia e Tecnologia de Materiais / Doutor em Engenharia Química
4

Studium sekrečních granulí buněčných linií a tkání produkujících insulin. / Study of secretory granules from insulin-producing tissues and cell lines.

Halušková, Petra January 2017 (has links)
Pancreas is known to be an organ producing a variety of exocrine and endocrine substances, where also insulin belongs. This hormone is produced in the body almost solely by specialized β-cells of the Langerhans islets and is stored here in secretory granules. As the β-cells contain large number of these vesicles, an organism can quickly respond to the glucose stimulation. Completely processed insulin is formed in the secretory granules probably as a hexamer, where six insulin molecules are coordinated along two zinc bivalent cations. Appropriate β-cell response to higher glucose level and following insulin secretion is one of the key processes that regulate metabolism in the body. In order to study insulin production, its effects or secretion, permanent pancreatic cell lines are often used as biological models, out of primary cells from islets of Langerhans. This diploma thesis is focused on two permanent cell lines INS-1E and BRIN-BD11. We searched for the ability of the cells to produce insulin, if the hormone is fully processed, as well as zinc content, which could have a great influence on insulin's processing. Using different methods we compared these two cell lines with cells from the Langerhans islets. We succeeded in isolation of secretory granules from all three cell types and we plan to...
5

Desenvolvimento de vacina terapêutica contra HPV16 / Development of a therapeutic vaccine against HPV16

Morale, Mirian Galliote 24 February 2010 (has links)
O câncer cervical é o segundo câncer mais comum entre mulheres no mundo. A maioria dos casos (83%) ocorre em países em desenvolvimento, onde são encontrados em estágios relativamente avançados e, conseqüentemente, a sobrevida média é de cerca de 49% após cinco anos. Portanto, uma vacina eficaz contra as infecções pelo HPV pode levar ao controle do câncer do colo do útero. Apesar de prevenir, a vacina profilática não é acessível em função do alto custo, além de não eliminar o vírus em mulheres já infectadas pelo HPV. Assim, propusemos o desenvolvimento de uma vacina terapêutica eficaz utilizando duas abordagens: VLPs (virus-like particles) quiméricas, que poderiam apresentar propriedades profiláticas e terapêuticas, obtidas da fusão das proteína L1 e E7; proteínas quiméricas obtidas a partir da fusão de epítopos das proteínas E6 e E7 do HPV16, com e sem ubiquitina. Após subclonagens, com a obtenção dos vetores pPICHOLI-L1ΔCE71-50 e pPICHOLI-L1ΔCE743-77, partiu-se para a indução da expressão das VLPs quiméricas em Pichia pastoris, das quais não foram detectadas expressão protéica. Realizaram-se inúmeras modificações no protocolo de indução. Mesmo após essas alterações não foi detectada nenhuma expressão das fusões L1ΔCE71-50 ou L1ΔCE743-77. Como alternativa de uma vacina terapêutica, nos propusemos a expressar em E. coli proteínas sintéticas originadas da fusão entre epítopos das proteínas E6 e E7 do HPV16, com ou sem Ubiquitina, visando aumentar a apresentação de peptídeos via MHC de classe I de modo a estimular a eliminação de células infectadas com HPV16, evitando e regredindo o desenvolvimento dessas células cancerosas. Com a proteína E6E7 solúvel e purificada, realizou-se um ensaio de imunização. Nesse experimento, 20% dos animais imunizados com a proteína E6E7 não apresentaram desenvolvimento de tumor após a inoculação de células TC1. Assim isso nos leva a crer que com o aumento da concentração de proteína e utilização de adjuvantes seria possível aumentar o número de animais resistentes ao desenvolvimento do tumor. Em um segundo experimento de imunização, comparamos as proteínas E6E7 e E6E7Ub, em duas concentrações, 15 e 40 µg, e também com ou sem o adjuvante whole cell pertussis (WCP). Independentemente da concentração e presença ou ausência de WCP, os grupos imunizados com E6E7Ub apresentaram proteção contra o tumor entre 80% e 100% dos camundongos, enquanto os grupos imunizados com E6E7 apresentaram proteção entre 0% e 25%. Esses resultados são promissores, ainda que preliminares, indicando um potencial de uso da proteína E6E7Ub como imunógeno para vacina terapêutica contra o câncer cervical induzido por HPV16 / Cervical cancer is the second most common cancer among women worldwide. Most cases (83%) occur in developing countries, where they are found in relatively advanced stages and, consequently, the median survival is about 49% after five years. Therefore, an effective vaccine against HPV infections can lead to control of cancer of the cervix. Although preventable, the prophylactic HPV vaccine is not accessible to all due to their high cost and in addition the vaccine does not eliminate the HPV in infected women. We have therefore proposed the development of effective therapeutic vaccines using two approaches: chimeric VLPs (virus-like particles), endowed with prophylactic and therapeutic properties, obtained from the fusion protein L1 and E7; chimeric proteins derived from the fusion of epitopes of proteins E6 and E7 of HPV16 with and without ubiquitin. After subcloning, we obtained the vectors pPICHOLI-L1ΔCE71-50 and L1 pPICHOLI- L1ΔCE743-77. After transformation of yeast Pichia pastoris with these constructions, the cells were induced, but it was not possible to detect any recombinant protein expression. As an alternative, we proposed the expression of synthetic proteins in E. coli derived from the fusion between epitopes of E6 and E7 proteins of HPV16 with or without Ubiquitin, in order to enhance the presentation of peptides through MHC class I to stimulate the elimination of HPV16-infected cells, preventing and regressing the development of cancer cells. Soluble E6E7 protein was purified and, 20% of the animals immunized with this protein did not develop tumor after inoculation of TC1 cells. In a second immunization experiment we compared the proteins E6E7 and E6E7Ub, in two concentrations, 15 and 40µg, with or without the adjuvant whole cell pertussis (WCP). Regardless of concentration and presence or absence of WCP, all the groups immunized with E6E7Ub showed protection against tumor between 80% and 100%, while the groups immunized with E6E7 showed protection from 0% to 25%. These results are promising and although preliminary, indicate the potential of E6E7Ub protein as an immunogen, for a therapeutic vaccine against cervical cancer induced by HPV16
6

Desenvolvimento de vacina terapêutica contra HPV16 / Development of a therapeutic vaccine against HPV16

Mirian Galliote Morale 24 February 2010 (has links)
O câncer cervical é o segundo câncer mais comum entre mulheres no mundo. A maioria dos casos (83%) ocorre em países em desenvolvimento, onde são encontrados em estágios relativamente avançados e, conseqüentemente, a sobrevida média é de cerca de 49% após cinco anos. Portanto, uma vacina eficaz contra as infecções pelo HPV pode levar ao controle do câncer do colo do útero. Apesar de prevenir, a vacina profilática não é acessível em função do alto custo, além de não eliminar o vírus em mulheres já infectadas pelo HPV. Assim, propusemos o desenvolvimento de uma vacina terapêutica eficaz utilizando duas abordagens: VLPs (virus-like particles) quiméricas, que poderiam apresentar propriedades profiláticas e terapêuticas, obtidas da fusão das proteína L1 e E7; proteínas quiméricas obtidas a partir da fusão de epítopos das proteínas E6 e E7 do HPV16, com e sem ubiquitina. Após subclonagens, com a obtenção dos vetores pPICHOLI-L1ΔCE71-50 e pPICHOLI-L1ΔCE743-77, partiu-se para a indução da expressão das VLPs quiméricas em Pichia pastoris, das quais não foram detectadas expressão protéica. Realizaram-se inúmeras modificações no protocolo de indução. Mesmo após essas alterações não foi detectada nenhuma expressão das fusões L1ΔCE71-50 ou L1ΔCE743-77. Como alternativa de uma vacina terapêutica, nos propusemos a expressar em E. coli proteínas sintéticas originadas da fusão entre epítopos das proteínas E6 e E7 do HPV16, com ou sem Ubiquitina, visando aumentar a apresentação de peptídeos via MHC de classe I de modo a estimular a eliminação de células infectadas com HPV16, evitando e regredindo o desenvolvimento dessas células cancerosas. Com a proteína E6E7 solúvel e purificada, realizou-se um ensaio de imunização. Nesse experimento, 20% dos animais imunizados com a proteína E6E7 não apresentaram desenvolvimento de tumor após a inoculação de células TC1. Assim isso nos leva a crer que com o aumento da concentração de proteína e utilização de adjuvantes seria possível aumentar o número de animais resistentes ao desenvolvimento do tumor. Em um segundo experimento de imunização, comparamos as proteínas E6E7 e E6E7Ub, em duas concentrações, 15 e 40 µg, e também com ou sem o adjuvante whole cell pertussis (WCP). Independentemente da concentração e presença ou ausência de WCP, os grupos imunizados com E6E7Ub apresentaram proteção contra o tumor entre 80% e 100% dos camundongos, enquanto os grupos imunizados com E6E7 apresentaram proteção entre 0% e 25%. Esses resultados são promissores, ainda que preliminares, indicando um potencial de uso da proteína E6E7Ub como imunógeno para vacina terapêutica contra o câncer cervical induzido por HPV16 / Cervical cancer is the second most common cancer among women worldwide. Most cases (83%) occur in developing countries, where they are found in relatively advanced stages and, consequently, the median survival is about 49% after five years. Therefore, an effective vaccine against HPV infections can lead to control of cancer of the cervix. Although preventable, the prophylactic HPV vaccine is not accessible to all due to their high cost and in addition the vaccine does not eliminate the HPV in infected women. We have therefore proposed the development of effective therapeutic vaccines using two approaches: chimeric VLPs (virus-like particles), endowed with prophylactic and therapeutic properties, obtained from the fusion protein L1 and E7; chimeric proteins derived from the fusion of epitopes of proteins E6 and E7 of HPV16 with and without ubiquitin. After subcloning, we obtained the vectors pPICHOLI-L1ΔCE71-50 and L1 pPICHOLI- L1ΔCE743-77. After transformation of yeast Pichia pastoris with these constructions, the cells were induced, but it was not possible to detect any recombinant protein expression. As an alternative, we proposed the expression of synthetic proteins in E. coli derived from the fusion between epitopes of E6 and E7 proteins of HPV16 with or without Ubiquitin, in order to enhance the presentation of peptides through MHC class I to stimulate the elimination of HPV16-infected cells, preventing and regressing the development of cancer cells. Soluble E6E7 protein was purified and, 20% of the animals immunized with this protein did not develop tumor after inoculation of TC1 cells. In a second immunization experiment we compared the proteins E6E7 and E6E7Ub, in two concentrations, 15 and 40µg, with or without the adjuvant whole cell pertussis (WCP). Regardless of concentration and presence or absence of WCP, all the groups immunized with E6E7Ub showed protection against tumor between 80% and 100%, while the groups immunized with E6E7 showed protection from 0% to 25%. These results are promising and although preliminary, indicate the potential of E6E7Ub protein as an immunogen, for a therapeutic vaccine against cervical cancer induced by HPV16
7

Vlastnosti expresních vektorů pro Corynebacterium glutamicum a jejich využití při studiu faktorů sigma RNA polymerasy / Characteristics of expression vectors for Corynebacterium glutamicum and their use for studies of sigma factors of RNA polymerase

Dvořáková, Pavla January 2017 (has links)
The aim of the thesis was to characterize chosen expression vectors used in biotechnologically important bacterial species, Corynebacterium glutamicum, and to test their use in studies of promoter activity control by sigma factors of RNA polymerase. Different properties of these vectors (level of expression of the cloned gene, leaky expression without inducer, dependence of expression level on inducer concentration and cell population homogeneity) were found by determination of expression level of the model gfpuv gene by fluorescence intensity assay of the produced protein and by gfpuv-expressing C. glutamicum cell population analysis using flow cytometry. The vector pEC-XT99A was chosen for testing the bi-plasmid system for assignment of a sigma factor to the chosen promoter. Although the level of expression provided by pEC-XT99A was not high, the vector showed no leaky expression, expression from the vector was comparable for a wide range of IPTG concentrations and the cell population was homogenous concerning the gene expression. Using pEC-XT99A from which individual stress sig genes were expressed, the σD factor was clearly assigned to the up-to-now unknown Pcg0420 promoter. Another vector for isolation and purification of C. glutamicum proteins was used to express the C. glutamicum sigM gene and to...

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