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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.
41

Identification of a transducin (beta)-like 3 protein as a potential biomarker of prediabetes from rat urine using proteomics

Mofokeng, Henrietta Refiloe January 2010 (has links)
<p>Obesity is a globally increasing disease particularly in developing countries and among children. It is mainly caused by intake of diets high in fat and the lack of physical activity. Obesity is a risk factor for diseases such as type II diabetes, high blood pressure, high cholesterol and certain cancers. Prediabetes is a condition where blood glucose levels are above normal but have not&nbsp / reached those of diabetes. It is difficult to diagnose, as there are no signs or symptoms. Some type II diabetes patients bear no symptoms at all and the disease is discovered late. Proteomics is a field that can provide opportunities for early diagnosis of diseases through biomarker discovery. The early diagnosis of diabetes can assist in the prevention and treatment of diabetes. Therefore there is a need for the early diagnosis of diabetes. Twenty Wistar rats were used. The rats were initially fed a CHOW diet, which is the standard balanced diet for rats, for 4 weeks. The rats were then divided into 2 groups of 10 where 1 group was fed CHOW and another was fed a high fat (HF) diet in order to induce obesity. The two groups were fed their respective diets for 18 weeks. Rats were weighed. Rats were placed in metabolic chambers and 24 hour urine samples were collected. Ketone levels were measured by Ketostix. Urine proteins were precipitated by acetone, quantified and separated on both the 1D SDS-PAGE and the 2D SDS-PAGE. Protein expression changes between CHOW and HF fed rats were determined and identified using MALDI-TOF mass spectrometry. Protein spots intensities increased and decreased between the CHOW and HF fed rats. Transducin (beta)-like 3 was identified as the only differentially expressed protein, which might serve as a potential biomarker for prediabetes.</p>
42

Effekter av kolhydraträkning vid diabetesdebut hos barn och ungdomar : En registerstudie

Lavin, Ingela, Wänman, Anna January 2014 (has links)
Abstract   Aims and objectives. To examine whether an intervention with carbohydrate- counting at onset of type 1 diabetes in children, has had any effect on metabolic indicators such as HbA1c , BMI-sds and total daily insulin / kg, 2 months and 1 year after onset by age and gender .Background. The pediatric department at the university hospital of Norrland in Umeå (NUS), has since several years a higher average HbA1c among children 0-17 years, compare with pediatric departments in the rest of Sweden.  Therefore, in autumn 2011, an intervention was made to teach children with diabetes and their parents to count carbohydrates from the onset of diabetes. Using this method they can regulate their insulin doses depending on the amount of carbohydrates they are eating. Design. This is an empirical registry study done on the basis of a quantitative method. It is retrospective controlled non- randomized with comparison group .Methods. The study included 46 children aged 0-17 years diagnosed with type 1 diabetes. Those who fell ill in 2009 (n=22) did not learn to use carbohydrate counting and served as a control group. The intervention group were diagnosed 2011-2012, (n=24), began using carbohydrate counting at the onset of diabetes.Results. The study shows with significant security that carbohydrate counting lowers HbA1c two months and one year after onset of type 1 diabetes. No significant difference was found in BMI-sds. The study shows no significant difference in HbA1c between the sexes.Conclusion.  Carbohydrate-counting from onset of diabetes gives a significant reduction of HbA1c without affecting BMI-sds significantly.Relevance to clinical practice. It is important that health professionals continue to teach and support families in carbohydrate counting from the onset of diabetes.Keywords. children, HbA1c, BMI- sds , type 1 diabetes , carbohydrate counting
43

Biochemical And Genetic Characterization Of Halobacterium Salinarium Strain Isolated From Tuz Lake In Central Anatolia

Cakici, Ozgur 01 January 2004 (has links) (PDF)
In this study, a halophilic archaea Halobacterium salinarium TG13 which is isolated from Tuz Lake in Central Anatolia was characterized biochemically and genetically. Halobacterium salinarium DSM3754 and Halobacterium salinarium S9 strains were used as a reference strain through the experiments. In biochemical characterization / total protein profiles of strains was compared by using 1D SDS PAGE. Total protein profile of the isolated strain has shown differences. The SDS-PAGE profile of the purified purple membrane showed only single band by coomassie staining. Molecular weight and pI values of the protein isolated from Halobacterium salinarium TG13 and Halobacterium salinarium S9 were estimated by 2D SDS-PAGE as 22 kD and 5.4, respectively. Photoactivity of purple membrane of the strains was investigated. pH change of the purple membranes were observed upon illumination. This protein might be corresponded to bacteriorhodopsin. In genetical characterization / polymorphism of genomic DNA of strains was scanned with RAPD-PCR. Plasmid DNA profiles of strains was determined to make use of RFLP technique. RAPD-PCR and RFLP analyses have shown that Halobacterium salinarium TG13 is different strain from reference Halobacterium salinarium strains (H.s. S9 and H.s. DSM3754).
44

Estudo da cinética e dos mecanismos da fototransformação de corantes ciânicos com dois cromóforos em interação com sistemas biomiméticos sob a ação da luz visível / Study of the kinetics and mechanisms of phototransformation of the interaction of cyanine dyes with two chromophores with biomimetic systems under the action of visible light

Érika Ribeiro e Silva 28 August 2015 (has links)
A Terapia Fotodinâmica (TFD) é um método de tratamento em que um composto fotossensibilizador (FS) é introduzido no organismo do paciente e, posteriormente, a região de tratamento é irradiada com luz. A combinação de oxigênio, luz e FS produz espécies que geram um efeito curativo. Os FS utilizados atualmente, embora eficazes, apresentam desvantagens. Neste trabalho, foram estudados os corantes ciânicos com dois cromóforos ou biscianinas (BCD) que apresentam características favoráveis na aplicação como FS na TFD. O objetivo deste trabalho foi analisar os efeitos da concentração, da composição do ambiente e da própria estrutura de três BCDs, com ângulos entre os seus cromóforos de 180°, 150° e 90°, nas características das suas fototransformações em tampão e na interação com micelas de SDS e DNA. A fototransformação pode causar a perda da fotoatividade do FS e gerar fotoprodutos (FPs) que tanto podem ser tóxicos como fotoativos. Os processos de tratamento na TFD e os de fototransformação são paralelos. Isso permite utilizar o monitoramento do processo de fototransformação para determinar o grau do processo de tratamento em tempo real. Por esse motivo, também foi estudada a fototransformação dos FPs formados durante a irradiação. A análise da fototransformação foi realizada utilizando técnicas espectroscópicas de absorção óptica e de fluorescência estática. Mudanças nos espectros de absorção óptica dos corantes indicaram a formação de agregados. A agregação diminui a velocidade de fototransformação devido ao aumento da probabilidade de dissipação da energia de excitação por processos não radiativos. Não houve formação de agregados na irradiação dos FPs, pois estes possuem menor tendência de agregação em comparação com o próprio corante. Semelhanças nos espectros dos FPs dos três corantes indicaram que eles possuem a mesma estrutura do cromóforo. Na ausência do oxigênio a velocidade de fototransformação diminui. Este fato juntamente com a relação entre os tempos da fotólise e os rendimentos quânticos do estado tripleto dos BCDs sugeriram a participação do oxigênio singleto na fototransformação. Na presença de sistemas biomiméticos em altas concentrações, os corantes estão em suas formas monoméricas. Nestas interações, os corantes também sofreram fototransformação, com velocidades diferentes daquelas em tampão, com formação de fotoprodutos. Na fototransformação dos corantes na presença de micelas de SDS, sugerimos que as moléculas dos corantes ficam mais protegidas do contato do oxigênio. Por outro lado, na interação com o DNA, as moléculas dos corantes ligadas na superfície do DNA se tornam mais suscetíveis ao ataque do oxigênio, fazendo com que a fototransformação seja mais rápida. / Photodynamic therapy (PDT) is a treatment that a photosensitizer compound (PS) is inserted into the patient\'s body and, subsequently, the treatment area is irradiated with light. The combination of oxygen, light and FS produce species that generate a curative effect. The FS currently used, although can be effective, have disadvantages. In this study, the cyanine dyes with two chromophores (BCD) or biscyanines that have favorable characteristics in the application as FS in PDT were studied. The aim of this study was to analyze the effects of concentration, environmental composition and the structure of three BCDs, with angles between chromophores 180, 150 and 90 degrees, in the characteristics of phototransformation of the dyes molecules in phosphate buffer and in the interaction with SDS micelles and DNA. The phototransformation can cause the loss of the FS photoactivity and generate photoproducts (PPs) that are both toxic as photoactive. The treatment processes in PDT and phototransformation are parallel. It allows the use of phototransformation monitoring process to determine the degree of realtime treatment process. For this reason, it was also studied the phototransformation of PPs formed during irradiation. The phototransformation analysis was performed using optical absorption and fluorescence spectroscopies. Changes in the optical absorption spectra of the dyes indicated the formation of aggregates. The aggregation reduces phototransformation rate due to the increased probability of dissipation of the excitation energy by non-radiative processes. There was no aggregate formation on irradiation of PPs because they have less tendency to aggregate compared with the dye. Similarities in the spectra of the three PPs indicated that they have the same structure of the chromophore. In the absence of oxygen phototransformation rate decreases. This fact together with the relationship between photolysis time and the quantum yields of the triplet state of the BCDs suggested the involvement of singlet oxygen in their phototransformation. The dyes were in their monomeric form at high SDS and DNA concentrations. In these interactions, the dyes also were phototransformed, with different rates compared with phosphate buffer, with formation of photoproducts. In the phototransformation of dyes in the presence of SDS micelles, we suggest that the dye molecules were more protected from oxygen contact. On the other hand, in the interaction of dyes and DNA molecules, the dye molecules bound on DNA surface become more available to oxygen attack, and the phototransformation becomes faster.
45

Determinação da estrutura terciária do peptídeo Cn-AMP1 isolado da água do coco verde, por Ressonância Magnética Nuclear (RMN) / Determining the tertiary structure of the peptide Cn-AMP1 isolated from coconut water by Nuclear Magnetic Resonance (NMR)

Santana, Mábio João 12 March 2013 (has links)
Submitted by Luanna Matias (lua_matias@yahoo.com.br) on 2015-03-27T16:12:44Z No. of bitstreams: 2 Dissertação - Mábio João Santana - 2013.pdf: 6762200 bytes, checksum: b7132dc5dcb7ad5864728fd4aa01e879 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-04-06T10:49:21Z (GMT) No. of bitstreams: 2 Dissertação - Mábio João Santana - 2013.pdf: 6762200 bytes, checksum: b7132dc5dcb7ad5864728fd4aa01e879 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-04-06T10:49:21Z (GMT). No. of bitstreams: 2 Dissertação - Mábio João Santana - 2013.pdf: 6762200 bytes, checksum: b7132dc5dcb7ad5864728fd4aa01e879 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-03-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aims to determine and analyze the three-dimensional structure in the lowest energy conformation of the peptide Cn-AMP1, isolated from green coconut water by 1H NMR. The determination of the 3D structure of the peptide under study was performed by homonuclear 2D 1H NMR experiments COSY, TOCSY and NOESY, using a 1 mM solution of the peptide Cn-AMP1 on Bruker AVANCE III 500 MHz (for 1H). The analysis of the correlation maps were made using the software NMRView, and the methodology adopted was the allocation sequence described by Wüthrich, where 200 structures were generated and selected the 20 lowest energy conformations to represent the overall three-dimensional structure Cn-AMP1 peptide. The peptide showed helical structure between residues Ser-1and Ala-6 in SDS- d25 micelles, 100 mM being structured randomly between residues Gln-7 and Met-9. However, under conditions of physiological pH, as in the absence of SDS micelles d25, the peptide showed no helix structure, predominating is randomly. / O presente trabalho tem como objetivo determinar e analisar a estrutura tridimensional em conformação de menor energia do peptídeo Cn-AMP1, isolado da água de coco verde por RMN de 1H. A determinação da estrutura 3D do peptídeo em estudo foi realizada através de experimentos de RMN de 1H homonuclear de COSY, TOCSY e NOESY, utilizando uma solução 1 mM do peptídeo Cn-AMP1, em espectrômetro BRUKER AVANCE III de 500 MHz, para o núcleo de hidrogênio. A análise dos mapas de correlação foram feitas usando o software NMRView, e a metodologia adotada foi a atribuição sequencial descrita por Wüthrich, onde foram geradas 200 estruturas e escolhidas as 20 conformações de menor energia global para representar a estrutura tridimensional do peptídeo Cn-AMP1. O peptídeo apresentou estruturação em hélice entre os resíduos Ser-1 e Ala-6, em micelas de SDS-d25, 100 mM, se estruturando randomicamente entre os resíduos Gln-7 e Met-9. No entanto, em condições de pH fisiológico, assim como na ausência de micelas de SDS-d25, o peptídeo não apresentou estrutura em hélice, prevalecendo a forma randômica.
46

Identification of a transducin (beta)-like 3 protein as a potential biomarker of prediabetes from rat urine using proteomics

Mofokeng, Henrietta Refiloe January 2010 (has links)
Magister Scientiae - MSc / Obesity is a globally increasing disease particularly in developing countries and among children. It is mainly caused by intake of diets high in fat and the lack of physical activity. Obesity is a risk factor for diseases such as type II diabetes, high blood pressure, high cholesterol and certain cancers. Prediabetes is a condition where blood glucose levels are above normal but have not reached those of diabetes. It is difficult to diagnose, as there are no signs or symptoms. Some type II diabetes patients bear no symptoms at all and the disease is discovered late. Proteomics is a field that can provide opportunities for early diagnosis of diseases through biomarker discovery. The early diagnosis of diabetes can assist in the prevention and treatment of diabetes. Therefore there is a need for the early diagnosis of diabetes. Twenty Wistar rats were used. The rats were initially fed a CHOW diet, which is the standard balanced diet for rats, for 4 weeks. The rats were then divided into 2 groups of 10 where 1 group was fed CHOW and another was fed a high fat (HF) diet in order to induce obesity. The two groups were fed their respective diets for 18 weeks. Rats were weighed. Rats were placed in metabolic chambers and 24 hour urine samples were collected. Ketone levels were measured by Ketostix. Urine proteins were precipitated by acetone, quantified and separated on both the 1D SDS-PAGE and the 2D SDS-PAGE. Protein expression changes between CHOW and HF fed rats were determined and identified using MALDI-TOF mass spectrometry. Protein spots intensities increased and decreased between the CHOW and HF fed rats. Transducin (beta)-like 3 was identified as the only differentially expressed protein, which might serve as a potential biomarker for prediabetes. / South Africa
47

Influência do clima nas características do sêmen e na composição proteica do plasma seminal em zebus e taurinos / Season influence upon semen characteristics and seminal plasma proteins in zebu and taurine

Reis, Juliana Domingos Archanjo dos 23 September 2013 (has links)
Made available in DSpace on 2016-01-26T18:55:38Z (GMT). No. of bitstreams: 1 Juliana Domingos Archanjo dos Reis.pdf: 354121 bytes, checksum: 0cd34b34c6da8a41a0682be81e391638 (MD5) Previous issue date: 2013-09-23 / Seminal plasma is a complex of secretions of the accessory reproductive organs of males with effects on sperm function. The quality of seminal plasma proteins may contribute to the fertility of bulls. The aim of this study was to determine the influence of season on the morphologic characteristics of the testes, epididymis, sperm and seminal plasma proteins by SDS-PAGE in Bos taurus indicus and Bos taurus taurus, bulls raised extensively. In this study 5 Nellore and 2 Simmental bulls, wewe used evaluated the scrotal and testicular morphometry, semen quality and the seminal plasma protein profile in SDS-PAGE in the dry and rainy seasons. Was obtained for a testicular volume TV = 460.14 cm3 during the rainy season and TV = 571.26 cm3 in the dry season. With respect to Zebu, in the rainy season the TV was 524.75 cm3 and 515.13 cm3 in the dry season. Sperm motility in the dry season for the taurine and total sperm defects in the rainy season for this same group of animals, showed as critical situation in the seminal analysis, suggesting the same attention when selecting bulls for purposes of natural mating. it is observed in 100% of the samples of the protein bands of 14 kDa, 21 kDa and 65 kDa in two stations evaluated. The seasons influence on morphology, and semen. The subspecies taurine showed great plasticity testicular volumes reflected in the testicle that reduces the rainy season. With respect to morphology, we found that there were significant effects of the dry season, improving the quality of sperm morphology. For electrophoresis, it was verified the presence of a large diversity of protein bands present in seminal plasma, and the bands 14, 21 and 65 kDa present in all the animals studied subspecies stations. It is suggested that the three protein bands found in all samples probably have beneficial action in relation to the framework sperm of bulls, collaborating with fertility. / O plasma seminal é um complexo de secreções dos órgãos reprodutores acessórios dos machos e aparentemente exercem importantes efeitos sobre a função espermática. A qualidade das proteínas do plasma seminal pode colaborar com a fertilidade dos touros. O objetivo desse estudo foi de determinar a influência das estações do ano sobre as características morfológicas dos testículos, epidídimos, sêmen e das proteínas do plasma seminal por meio da eletroforese SDS PAGE em touros Bos taurus indicus e Bos taurus taurus, criados extensivamente. Foram utilizados 5 touros Nelore e 2 Simental, avaliou-se a morfometria testicular e escrotal, qualidade do sêmen e perfil proteico do plasma seminal em SDS-PAGE nas estações seca e chuvosa. Obteve-se para os taurinos um volume testicular VT = 460,14 cm3 na estação chuvosa e VT = 571,26 cm3 na estação seca. Com relação aos zebuínos, na estação chuvosa o VT foi de 524,75 cm3 e de 515,13 cm3 na estação seca. A motilidade espermática na estação seca para os taurinos e os defeitos espermáticos totais na estação chuvosa para esse mesmo grupo de animais, mostraram-se como pontos de estrangulamento dentro da análise do espermograma, sugerindo especial atenção dos mesmos quando da seleção de touros para fins de monta natural. As estações influenciaram nas características morfológicas e do sêmen. A subespécie taurina revelou uma grande plasticidade testicular, refletida na volumetria do testículo que se reduz na estação chuvosa. Com relação à morfologia espermática, verificou-se que houve efeito significativo da estação seca, melhorando a qualidade morfológica dos espermatozóides. Para a eletroforese, verificou-se a presença de grande diversidade de bandas proteicas presentes no plasma seminal, sendo as bandas de 14, 21 e 65 kDA presentes em todos os animais das duas subespécies nas estações estudadas. Sugere-se que as três bandas protéicas encontradas em todas as amostras, provavelmente, possuam ação benéfica em relação ao quadro espermático dos touros, colaborando com a fertilidade.
48

Influência do clima nas características do sêmen e na composição proteica do plasma seminal em zebus e taurinos / Season influence upon semen characteristics and seminal plasma proteins in zebu and taurine

Reis, Juliana Domingos Archanjo dos 23 September 2013 (has links)
Made available in DSpace on 2016-07-18T17:53:12Z (GMT). No. of bitstreams: 1 Juliana Domingos Archanjo dos Reis.pdf: 354121 bytes, checksum: 0cd34b34c6da8a41a0682be81e391638 (MD5) Previous issue date: 2013-09-23 / Seminal plasma is a complex of secretions of the accessory reproductive organs of males with effects on sperm function. The quality of seminal plasma proteins may contribute to the fertility of bulls. The aim of this study was to determine the influence of season on the morphologic characteristics of the testes, epididymis, sperm and seminal plasma proteins by SDS-PAGE in Bos taurus indicus and Bos taurus taurus, bulls raised extensively. In this study 5 Nellore and 2 Simmental bulls, wewe used evaluated the scrotal and testicular morphometry, semen quality and the seminal plasma protein profile in SDS-PAGE in the dry and rainy seasons. Was obtained for a testicular volume TV = 460.14 cm3 during the rainy season and TV = 571.26 cm3 in the dry season. With respect to Zebu, in the rainy season the TV was 524.75 cm3 and 515.13 cm3 in the dry season. Sperm motility in the dry season for the taurine and total sperm defects in the rainy season for this same group of animals, showed as critical situation in the seminal analysis, suggesting the same attention when selecting bulls for purposes of natural mating. it is observed in 100% of the samples of the protein bands of 14 kDa, 21 kDa and 65 kDa in two stations evaluated. The seasons influence on morphology, and semen. The subspecies taurine showed great plasticity testicular volumes reflected in the testicle that reduces the rainy season. With respect to morphology, we found that there were significant effects of the dry season, improving the quality of sperm morphology. For electrophoresis, it was verified the presence of a large diversity of protein bands present in seminal plasma, and the bands 14, 21 and 65 kDa present in all the animals studied subspecies stations. It is suggested that the three protein bands found in all samples probably have beneficial action in relation to the framework sperm of bulls, collaborating with fertility. / O plasma seminal é um complexo de secreções dos órgãos reprodutores acessórios dos machos e aparentemente exercem importantes efeitos sobre a função espermática. A qualidade das proteínas do plasma seminal pode colaborar com a fertilidade dos touros. O objetivo desse estudo foi de determinar a influência das estações do ano sobre as características morfológicas dos testículos, epidídimos, sêmen e das proteínas do plasma seminal por meio da eletroforese SDS PAGE em touros Bos taurus indicus e Bos taurus taurus, criados extensivamente. Foram utilizados 5 touros Nelore e 2 Simental, avaliou-se a morfometria testicular e escrotal, qualidade do sêmen e perfil proteico do plasma seminal em SDS-PAGE nas estações seca e chuvosa. Obteve-se para os taurinos um volume testicular VT = 460,14 cm3 na estação chuvosa e VT = 571,26 cm3 na estação seca. Com relação aos zebuínos, na estação chuvosa o VT foi de 524,75 cm3 e de 515,13 cm3 na estação seca. A motilidade espermática na estação seca para os taurinos e os defeitos espermáticos totais na estação chuvosa para esse mesmo grupo de animais, mostraram-se como pontos de estrangulamento dentro da análise do espermograma, sugerindo especial atenção dos mesmos quando da seleção de touros para fins de monta natural. As estações influenciaram nas características morfológicas e do sêmen. A subespécie taurina revelou uma grande plasticidade testicular, refletida na volumetria do testículo que se reduz na estação chuvosa. Com relação à morfologia espermática, verificou-se que houve efeito significativo da estação seca, melhorando a qualidade morfológica dos espermatozóides. Para a eletroforese, verificou-se a presença de grande diversidade de bandas proteicas presentes no plasma seminal, sendo as bandas de 14, 21 e 65 kDA presentes em todos os animais das duas subespécies nas estações estudadas. Sugere-se que as três bandas protéicas encontradas em todas as amostras, provavelmente, possuam ação benéfica em relação ao quadro espermático dos touros, colaborando com a fertilidade.
49

Caracterização proteômica do vinho espumante brasileiro e sua relação com a qualidade da formação de espuma / Characterization of brazilian sparkling wine proteomics and its relationship with the foaming formation quality

Souza, Giselle Ribeiro de 15 February 2016 (has links)
Uma das características de qualidade dos vinhos espumantes, e que também impõe a sua identidade, é a aparência das borbulhas. Tradicionalmente, acredita-se que a capacidade de formação e estabilização dessas borbulhas depende de macromoléculas do vinho, em especial das proteínas, devido a sua ação tensoativa. Este trabalho de doutorado visou o estudo proteômico do vinho espumante brasileiro a fim de identificar quais proteínas estão presentes nesses vinhos para entender melhor a influência dessas na estabilização da espuma (perlage e colarinho), e com o intuito de potencializar essa característica em nossos produtos. Foram utilizados os métodos de extração de proteínas clássico, ácido tricloroacético/acetona e de última geração, biblioteca combinatória de ligantes peptídicos, sendo estas separadas por SDS-PAGE, 2DE e OFFGEL. As proteínas extraídas foram digeridas com tripsina e a mistura de peptídeos analisada por nLC-MS/MS com metodologia shotgun. Os resultados iniciais obtidos por eletroforese 2DE e OFFGEL, mostraram a presença de três grupos de proteínas de massa molecular distintas, sendo duas próximas a 25 kDa e uma próxima a 70 kDa. Estas proteínas parecem estar presentes nos vinhos em mais de uma isoforma evidenciado pelo espalhamento de todas as bandas de mesma massa molecular em diferentes pH. Foram identificadas 40 proteínas, sendo 17 proteínas de organismos do sub-reino Viridiplantae e 23 proteínas pertencentes ao gênero Saccharomyces, onde 10 e 6 proteínas, respectivamente, estão presentes em pelo menos duas amostras de espumantes nacionais. Dessas, seis proteínas foram identificadas pela primeira vez em vinhos. Três proteínas originárias da levedura Saccharomyces cerevisiae estão presentes em todos os produtos analisados, podendo essas proteínas serem as responsáveis pela melhor formação de espuma observada em nossos produtos em relação ao Champagne (vinho espumante tradicional da França). / The type of fizzy bubbles is one of the aspects that characterizes the quality of sparkling wines and also helps defining their identity. Traditionally, it is believed that the ability of these bubbles to form and stabilize depends on the macromolecules found in the wine, particularly proteins, due to their surfactant action. The aim of this work is the proteomic study of the brazilian sparkling wines in order to identify which proteins are present to better understand the influence of these molecules in the foam formation (perlage and collar), in order to improve our products. The protein extraction methods used were the classical TCA/acetone precipitation and the modern combinatory peptide ligand library. Then, proteins were separated by SDS-PAGE, 2DE and OFFGEL. The protein extracted were digested with trypsin and the peptide mixture were analyzed with nLC-MS/MS using the shotgun method. The first results obtained by electrophoresis 2DE and OFFGEL showed the presence of three groups of proteins with different molecular mass, two of them close to 25 kDa and the other one close to 70 kDa. These proteins appear to be present in wine in more than one isoform evidenced by spreading in all bands of similar molecular weight at different pH. In total, 40 proteins were identified, 17 protein from Viridiplantae sub-kingdom organisms and 23 proteins belonging to Saccharomyces genus, where 10 and 6 proteins, respectively, are present in at least two samples of domestic sparkling wines. Six of those proteins were identified in wine for the first time. Three proteins originating from Saccharomyces cerevisiae are present in all analyzed products, and those may be responsible for a better foam formation observed in our products in comparison to Champagne (traditional French sparkling wine).
50

Proteinograma da secreção láctea de cabras / Goat milk proteinogram

Raimondo, Raquel Fraga e Silva 17 March 2011 (has links)
O objetivo do presente estudo foi estabelecer os valores de referência do proteinograma de soro lácteo por meio da técnica de eletroforese SDS-PAGE para a lactação plena e avaliar os efeitos do processo de secagem da glândula mamária, fase colostral e primeiro mês de lactação, fase de lactação, número de lactações, isolamento bacteriano e infecção pelo VCAE nas proteínas da secreção láctea de cabras da raça Saanen. Foram analisadas, entre 2007 e 2010, 545 amostras de leite provenientes de 185 cabras em diversas fases da lactação. Durante a lactação plena, baseado nos resultados dos intervalos de confiança, foram determinados os seguintes valores de referência: proteína total entre 2.940,0 e 3.050 mg/dL; proteína do soro lácteo entre 903,0 e 973,0 mg/dL; lactoferrina entre 68,0 e 77,0 mg/dL; albumina entre 88,0 e 97,0 mg/dL; imunoglobulina cadeia pesada entre 93,3 e 103,0 mg/dL; imunoglobulina cadeia leve entre 132,7 e 146,0 mg/dL; &beta;-lactoglobulina entre 299,0 e 329,0 mg/dL e &alpha;-lactoalbumina entre 213,0 e 229,5 mg/dL. Os valores absolutos de proteína total, proteína do soro e frações protéicas aumentam durante a secagem da glândula. Antes da secagem predominavam as frações de &beta;-Lg e &alpha;-La, a partir do 3&ordm; dia, ocorre o surgimento das novas frações e a alteração do perfil protéico sem que haja o predomínio de nenhuma fração. A fase colostral, primeiras 24 horas de lactação, determinam as maiores concentrações de proteína total, proteína do soro e frações protéicas que diminuem após as primeiras 12 horas de lactação estabilizando após o 5&ordm; dia. No colostro as imunoglobulinas são predominantes, e após o período de transição do colostro para o leite as frações &beta;-Lg e &alpha;-La são predominantes. Nos primeiros 15 dias de lactação, devido à influência da fase colostral, observa-se que as concentrações de proteína total e proteína do soro lácteo são maiores. A partir desse momento permanecem estáveis voltando a aumentar no final da lactação. As frações protéicas do soro de leite (lactoferrina, albumina sérica, imunoglobulina de cadeia pesada, imunoglobulina de cadeia leve, &beta;-Lg e &alpha;-La) também são máximas nos primeiros 15 dias de lactação e diminuem ao longo do período. A concentração de proteína do soro e suas frações em cabras primíparas foi menor quando comparadas com cabras pluríparas. O isolamento bacteriano não influencia as concentrações de proteína total do leite e proteína do soro lácteo de cabras, contudo a concentração de lactoferrina é maior e as concentrações de &beta;-Lg e &alpha;-La são menores em amostras com isolamento bacteriano. O CAEV não influencia as concentrações de proteína total do leite e proteína do soro lácteo de cabras, contudo a concentração de lactoferrina é maior e a concentração de e &alpha;-La é menor em cabras sororeagentes positivas ao VCAE. / The aim of this study was to establish reference values of the whey protein through the technique of SDS-PAGE for the full lactation and to evaluate the effects of the dry period of the mammary gland, colostral phase and first month of lactation, lactation, lactation number, bacterial isolation and VCAE infection in proteins of milk secretion in Saanen goats. Were analyzed between 2007 and 2010, 545 milk samples from 185 goats at different stages of lactation. During full lactation, based on the results of the confidence intervals were determined the following reference values: total protein between 2,940.0 and 3,050 mg / dL; whey protein between 903.0 and 973.0 mg / dL; lactoferrin between 68.0 and 77.0 mg / dL, serum albumin between 88.0 and 97.0 mg /dL, immunoglobulin heavy chain between 93.3 and 103.0 mg / dL, immunoglobulin light chain between 132.7 and 146, 0 mg / dL, &beta;-lactoglobulin between 299.0 and 329.0 mg / dL and &alpha;-lactalbumin between 213.0 and 229.5 mg / dL. The absolute values of total protein, whey protein and protein fractions increase during the dry period. Prevailed prior to dry period the fractions of &beta;-Lg and &alpha;-La from the 3rd day, occurs the emergence of new fractions and protein profile changes without the predominance of any fraction The colostral phase, the first 24 hours of lactation, determine the highest concentrations of total protein, whey protein and protein fractions that decrease after the first 12 hours of lactation stabilized after the 5th day. Immunoglobulin in colostrum is prevalent, and after the period of transition from colostrum to milk fractions &beta;-Lg and &alpha;-La are predominant. In the first 15 days of lactation, due to the influence of colostral phase, it is observed that the concentrations of total protein and whey protein are higher. From then remain stable before rising again in late lactation. The protein fractions of whey (lactoferrin, serum albumin, immunoglobulin heavy chain, immunoglobulin light chain, &beta;-Lg and &alpha;-La) are also maximal in the first 15 days of lactation and decrease during the period. The concentration of whey protein and protein fractions in heifers are smaller when compared with multiparous goats. Bacteria isolation does not influence the concentrations of total protein from milk and whey protein of goats, but the concentration of lactoferrin is increased and the concentrations of &beta;-Lg and &alpha;-La is smaller in samples with bacterial isolation. The CAEV does not influence the concentrations of total protein and whey protein in goat, but the concentration of lactoferrin is higher and concentration of &alpha;-La is less in goat positive by the CAEV.

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