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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.
11

Determination of Membrane Fluidity And Correlate Its Effect in Bulk Bacterial Cell Respiration

Ojha, Krishna Raj 15 July 2020 (has links)
No description available.
12

Intraepiteliniai gimdos kaklelio pokyčiai ir žmogaus papilomos viruso integracija / Cervical intraepithelial lesions and integration of human papillomavirus

Šepetienė, Agnė 07 March 2011 (has links)
Disertacijoje nagrinėjama sąsaja tarp žmogaus papilomos viruso (ŽPV) integracijos į gimdos kaklelio epitelio ląstelių genomą ir intraepitelinių gimdos kaklelio pokyčių. Pagrindinis darbo tikslas – nustatyti, kaip 16 tipo ŽPV DNR integracijos laipsnis (ŽPV E2 geno iškrita) susijęs su intraepiteliniais gimdos kaklelio pokyčiais. Ištyrus 253 moteris nustatyta, kad dauguma moterų buvo infekuotos 16 tipo ŽPV. Dažniausiai nustatyta II laipsnio šio tipo ŽPV integracija. Statistiškai reikšmingo skirtumo analizuojant sąsajas tarp ŽPV E2 geno integracijos pobūdžio ir intraepitelinių gimdos kaklelio pokyčių laipsnio nenustatyta. Tai, kad integruotų 16 tipo ŽPV formų nustatyta esant nežymių arba net nesant intraepitelinių gimdos kaklelio pokyčių, rodo, jog viruso integracija yra ankstyvasis kancerogenezės įvykis. Pažymėtina, kad pakartotinio patikrinimo metu 50 proc. ŽPV infekuotų moterų konstatuota mRNR raiška, kas rodo besitęsiančią aktyvią ŽPV infekciją. Atliktas tyrimas yra svarbus gerinant patikros dėl gimdos kaklelio patologijos programas: derinant Pap testą ir ŽPV DNR bei kitų ŽPV žymenų nustatymą (mRNR, E2 geno iškrita) galima atrinkti infekuotas ŽPV moteris, kurioms dar nėra klinikinių požymių, tačiau jos priklauso didelės rizikos susirgti gimdos kaklelio vėžiu grupei. / This dissertation observes the association between human papillomavirus (HPV) integration into the host cell genome and cervical intraepithelial lesions. The aim of this study is to determine how the grade of HPV16 DNA integration into the host cell genome (HPV E2 gene deletion) is related to cervical intraepithelial lesions. 253 women were screened for HPV infection and the majority was diagnosed with HPV type 16. The most frequently determined was HPV grade II integration. No statistically significant difference was defined while analyzing the relations between the status of HPV E2 gene integration and the grade of cervical intraepithelial lesions. The fact that integration of HPV type 16 was determined in low grade cervical squamous intraepithelial lesions or in cases with no intraepithelial lesions shows that virus integration occurs at the early stage of carcinogenesis. It is noteworthy that during the follow-up (secondary visit after 6 month) 50% of HPV positive women were identified with mRNR expression which probably establishes the presence of persistent active HPV infection. The research provided is highly significant for improvement of cervical cancer screening programms. Adjusting Pap smear, HPV DNA detection and determination of other HPV biomarkers (such as E2 gene deletion mRNR), it becomes possible to separate out HPV positive women with no clinical signs, although, belonging to the of high risk group for cervical carcinoma developing.
13

Estudo funcional do gene gluc31 que codifica uma β-1,3-glucanase da família GH16 de Trichoderma harzianum / Functional characterization of the gluc31 gene that encodes an β-1,3-glucanase of the GH16 family of Trichoderma harzianum

Ribeiro, Marcela Suriani 28 April 2017 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-05-18T19:09:17Z No. of bitstreams: 2 Tese - Marcela Suriani Ribeiro - 2017.pdf: 1795199 bytes, checksum: fb63e9f789cfefb42f31cba029a29f4f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-19T10:43:53Z (GMT) No. of bitstreams: 2 Tese - Marcela Suriani Ribeiro - 2017.pdf: 1795199 bytes, checksum: fb63e9f789cfefb42f31cba029a29f4f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-19T10:43:53Z (GMT). No. of bitstreams: 2 Tese - Marcela Suriani Ribeiro - 2017.pdf: 1795199 bytes, checksum: fb63e9f789cfefb42f31cba029a29f4f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The genus Trichoderma includes species that have the ability to antagonize plant pathogens in a complex process ranging from antibiosis, competition for nutrients, mycoparasitism and induction of defense mechanisms in plants or a combination of these. Trichoderma species are known for their ability to produce lytic enzymes such as exoglucanases, endoglucanases, chitinases, and proteases that is essential for phytopathogen cell wall degradation. In the development and differentiation processes of Trichoderma, β-glucanases contributes significantly to the morphogenetic-morphological process that lead to the presence of β-glucans as the main component of fungi wall. In this work, we studied the functional role of the gluc31 gene that encodes an endo β-1,3-glucanase of the GH16 family of Trichoderma harzianum ALL42 through the deletion of this gene. This study demonstrated that the absence of Δgluc31 gene did not affect the in vivo mycoparasitism ability of the mutant T. harzianum ALL42, however the involvement of this gene in cell wall remodeling and synthesis were demonstrated. In the absence of the gluc31 gene, a higher deposition of chitin polymers on the cell wall of the mutant hyphae was observed. The absence of the gluc31 gene in T. harzianum also demonstrated an effect on the expression of other genes belonging to the family 16 of glycosyl hydrolases, due to the function redundancy found among the glucanases. / O gênero Trichoderma inclui espécies que possuem habilidade de antagonizar patógenos de plantas em um processo complexo que vão desde antibiose, competição por nutrientes, micoparasitismo, indução de mecanismos de defesa em plantas ou ainda uma combinação desses. Espécies de Trichoderma são conhecidas por sua capacidade de produzir enzimas líticas tais como exoglucanases, endoglucanases, quitinases e proteases que desempenham papéis importantes na degradação da parede de fitopatógenos. Nos processos de desenvolvimento e diferenciação de Trichoderma, as β-glucanases contribuem de forma significativa no processo morfogenéticomorfolítico uma vez que a β-glucanas é o componente principal da sua parede. Nesse trabalho, realizou-se o estudo do papel funcional do gene gluc31 que codifica uma endo β-1,3-glucanase da família GH16 de Trichoderma harzianum ALL42, através da deleção deste gene. Observamos que a ausência do gene gluc31 não afetou a capacidade de micoparasitismo, in vitro, da espécie mutante de T. harzianum ALL42, entretanto, o envolvimento deste gene na síntese e remodelamento da parede celular foi demonstrado. Na ausência do gene gluc31, uma maior quantidade de polímero de quitina na parede celular das hifas da linhagem mutante Δgluc31 foi observado. A ausência do gene gluc31 em T. harzianum demonstrou ainda um efeito sobre a expressão dos outros genes pertencentes à família 16 de glicosil hidrolases em ensaios de RT-qPCR, devido a redundância de função entre as glucanases.
14

Caracterização fenotípica e molecular de linhagens atenuadas de Salmonella enterica Typhimurium = Phenotipic and molecular characterization of attenuated strains of Salmonella enterica Typhimurium / Phenotipic and molecular characterization of attenuated strains of Salmonella enterica Typhimurium

Neves, Meiriele da Silva das, 1990- 27 August 2018 (has links)
Orientador: Marcelo Brocchi / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T16:38:13Z (GMT). No. of bitstreams: 1 Neves_MeirieledaSilvadas_M.pdf: 2620199 bytes, checksum: 70b2df72cfdb93196c91a87c813e12e9 (MD5) Previous issue date: 2015 / Resumo: O gênero Salmonella pertence à família Enterobacteriaceae que agrupa bacilos Gram-negativos, anaeróbios facultativos, fermentadores e geralmente flagelados. S. enterica é um dos patógenos de origem alimentar mais prevalente, sendo que infecções causadas por essa bactéria podem estar relacionadas a praticamente todos os tipos de alimentos. O trabalho foi proposto com o intuito de realizar a caracterização fenotípica e molecular de linhagens atenuadas de Salmonella enterica Typhimurium para genes codificadores de proteínas associadas ao nucleóide (NAPs Nucleoid associated Proteins). As características fenótipicas dos mutantes nulos de Salmonella enterica para os genes ihfA ou ihfB, codificadores das subunidades A e B de IHF, foram avaliadas através de crescimento in vitro, motilidade, sobrevivência frente ao estresse nutricional (sobrevivência em fase estacionária), sob condições ácidas, na presença de sais biliares e quanto à capacidade de invasão e sobrevivência em macrófagos (linhagem J774A.1). Testes de confirmação da atenuação e avaliação da capacidade de induzir proteção em caso de infecção por S. enterica foram realizados utilizando o modelo murino. Os mutantes não apresentaram diferença no crescimento in vitro e na capacidade de sobreviver na presença de sais biliares em comparação com a linhagem selvagem. As linhagens mutantes para os genes ihfA ou ihf ihf ihfB) apresentaram uma menor capacidade de sobrevivência sob condições ácidas quando comparadas com a linhagem selvagem. A motilidade dos mutantes simples também foi reduzida. Os mutantes simples e duplo apresentaram maior capacidade de sobreviver sob estresse nutricional quando comparados com a linhagem selvagem. O mutante para o gene ihfA e o duplo mutante apresentaram um aumento na capacidade de invadir macrófagos. ihf ihfB mostraram uma capacidade aumentada em sobreviver no interior de macrófagos quando comparadas com a linhagem selvagem. Os mutantes nulos viii de Salmonella enterica para os genes ihfA ou ihfB apresentam atenuação, em diferentes graus, quanto à virulência e apresentaram capacidade de induzir proteção no modelo murino de infecção por S. enterica. Esses resultados demonstram que essa proteína apresenta função relacionada com a virulência bacteriana, sendo um importante alvo de estudo na busca de linhagens atenuadas / Abstract: The genus Salmonella belongs to the Enterobacteriaceae family that comprises Gram-negative bacillus, facultative anaerobe, fermenting and generally flagellate. S. enterica is one of the most prevalent food-borne pathogen, and infections caused by this bacterium can be associated to almost all types of food. The work was proposed with the purpose of performing phenotypic and molecular characterization of attenuated strains of Salmonella enterica Typhimurium for genes encoding proteins associated with the nucleoid (NAPs - Nucleoid associated Proteins). The phenotypic characteristics of the null mutants of Salmonella enterica for genes ihfA or ihfB, encoding the A and B subunits of IHF, were evaluated by in vitro growth, motility, survival under nutritional stress (survival in the stationary phase), under acidic conditions, in the presence of bile salts and for the ability of invasion and survival in macrophages (J774A.1 strain). Attenuation tests and evaluation of the capacity to induce protection in case of infection by S. enterica were performed using the murine model. The mutants showed no difference in the in vitro growth and the ability to survive in the presence of bile salts in comparison with the wild type strain. The single mutant for ihfA or ihf ihf ihfB) showed decreased survival under acidic conditions when compared to the wild type strain. Motility of single mutants was also reduced. Single and double mutants showed higher ability to survive under nutritional stress when compared with the wild type strain. The mutant gene for ihfA and the double mutant showed an increased ability to invade ihf ihfB mutants showed an increased ability to survive within macrophages when compared with the wild type strain. Null mutants of Salmonella enterica for ihfA or ihfB genes exhibited attenuation, to varying degrees, for virulence and showed ability to induce protection in a murine model of infection by S. enterica. x These results demonstrate that this protein has function associated to bacterial virulence and is an important subject of study in search for attenuated strains / Mestrado / Genetica de Microorganismos / Mestra em Genética e Biologia Molecular
15

Chronic Granulomatous Disease, The Mcleod Phenotype and the Contiguous Gene Deletion Syndrome - a Review

Watkins, Casey E., Litchfield, John, Song, Eunkyung, Jaishankar, Gayatri B., Misra, Niva, Holla, Nikhil, Duffourc, Michelle, Krishnaswamy, Guha 23 November 2011 (has links)
Chronic Granulomatous Disease (CGD), a disorder of the NADPH oxidase system, results in phagocyte functional defects and subsequent infections with bacterial and fungal pathogens (such as Aspergillus species and Candida albicans). Deletions and missense, frameshift, or nonsense mutations in the gp91 phox gene (also termed CYBB), located in the Xp21.1 region of the X chromosome, are associated with the most common form of CGD. When larger X-chromosomal deletions occur, including the XK gene deletion, a so-called "Contiguous Gene Deletion Syndrome" may result. The contiguous gene deletion syndrome is known to associate the Kell phenotype/McLeod syndrome with diseases such as X-linked chronic granulomatous disease, Duchenne muscular dystrophy, and X-linked retinitis pigmentosa. These patients are often complicated and management requires special attention to the various facets of the syndrome. © 2011 Watkins et al; licensee BioMed Central Ltd.
16

Chronic Granulomatous Disease, the Mcleod Phenotype and the Contiguous Gene Deletion Syndrome- a Review

Watkins, Casey E., Litchfield, John, Song, Eunkyung, Jaishankar, Gayatri B., Misra, Niva, Holla, Nikhil, Duffourc, Michelle, Krishnaswamy, Guha 23 November 2011 (has links)
Chronic Granulomatous Disease (CGD), a disorder of the NADPH oxidase system, results in phagocyte functional defects and subsequent infections with bacterial and fungal pathogens (such as Aspergillus species and Candida albicans). Deletions and missense, frameshift, or nonsense mutations in the gp91 phox gene (also termed CYBB), located in the Xp21.1 region of the X chromosome, are associated with the most common form of CGD. When larger X-chromosomal deletions occur, including the XK gene deletion, a so-called "Contiguous Gene Deletion Syndrome" may result. The contiguous gene deletion syndrome is known to associate the Kell phenotype/McLeod syndrome with diseases such as X-linked chronic granulomatous disease, Duchenne muscular dystrophy, and X-linked retinitis pigmentosa. These patients are often complicated and management requires special attention to the various facets of the syndrome.
17

Characterization of human chromosome 22 : cloning of breakpoints of the constitutional translocation t(11;22)(q23;q11) and detection of small constitutional deletions by microarray CGH /

Tapia Páez, Isabel, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 6 uppsatser.
18

Dynamics of the bacterial genome rates and mechanisms of mutation /

Koskiniemi, Sanna, January 2010 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2010.
19

Inflammation-associated genes and genetic variations in colorectal cancer /

Elander, Nils, January 2009 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2009. / Härtill 5 uppsatser.
20

Estudo funcional do gene que codifica um transportador de membrana MFS em Colletotrichum lindemuthianum / Functional study of a gene that encodes a MFS membrane transporter in Colletotrichum lindemuthianum

Pereira, Monalessa Fábia 18 February 2011 (has links)
Made available in DSpace on 2015-03-26T13:51:54Z (GMT). No. of bitstreams: 1 texto completo.pdf: 4267302 bytes, checksum: e9b9d7cbe9f5e7cfd714ca533302e571 (MD5) Previous issue date: 2011-02-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Colletotrichum lindemuthianum is the causal agent of common bean antracnose. This fungus, like other phytopatogens, is constantly exposed to several toxic compounds from many sources, what makes indispensable the development of protection strategies against these products. One of these strategies is related to membrane transporters proteins like the Major Facilitator Superfamily (MFS), that could provide protection against toxic compounds or minimizing its action, being essential for the fungal cellular viability maintenance. In this context, this work aimed to inactivate the mfs1 gene encoding a MFS membrane transporter and investigate the phenotypic alterations entailed in an isolate C. lindemuthianum mutant LV49 (race 89) for this gene. To obtain the mutant, it was necessary to confirm if mfs1 gene was organized as a single copy in the C. lindemuthianum genome. The mfs1 gene can be organized in a cluster in view that a second open reading frame, which corresponds to a transcription factor superfamily containing a Zn2-Cys6 domain, identified as clft1, was observed in 3` downstream region of this gene. The mfs1 promoter analysis revealed a putative mfs1 element that is recognized by proteins of this family, what suggests that this protein could be related to the mfs1 expression regulation. The Split-Marker technique proved to be efficient in C. lindemuthianum mfs1 gene inactivation enabling the study of mfs1 function in a mutant by specific integrations without ectopic integrations. The Δmfs1 mutant showed no differences in drug sensibility profile when commonly drugs employed in antracnose control was used and in relation to pathogenicity, the mutant symptoms started earlier on susceptible bean leaves, showing a stress situation due to the genic product absence. It was also observed that mfs1 presents a primordial role in C. lindemuthianum cellular viability maintenance, what was confirmed by the altered conidiation observed, confirming that this gene encodes for a specific hexose membrane transporter, specifically carbon sources like glucose, mannose and fructose. The protein Mfs1 phylogenetic analysis allow us to conclude that this transporter is a SP family member and the MFS proteins are strongly related with the transported substance. Studies conducted with MFS transporters are important to broaden the knowledge of these proteins and to understand the cell viability in C. lindemuthianum. / O fungo Colletotrichum lindemuthianum é o agente causal da antracnose do feijoeiro comum. Este fungo, assim como outros fungos fitopatógenos estão constantemente expostos a uma grande variedade de compostos tóxicos provenientes de várias fontes, o que torna imprescindível para estes o desenvolvimento de mecanismos de proteção contra estes produtos. Uma dessas estratégias está relacionada com a presença de proteínas transportadoras de membrana, como as pertencentes à Principal Superfamília Facilitadora (MFS), que podem fornecer aos fungos proteção contra compostos tóxicos evitando ou minimizando a ação destes, sendo em sua maioria essenciais para a manutenção da viabilidade celular. Este trabalho teve como objetivo inativar o gene mfs1 que codifica para um transportador de membrana da família MFS e investigar as alterações fenotípicas ocasionadas em um mutante C. lindemuthianum isolado LV49 (raça 89) para este gene. Para a obtenção do mutante foi necessário confirmar que o gene mfs1 encontrava-se presente em cópia única no genoma de C. lindemuthianum. O gene mfs1 pode estar organizado em um conjunto de genes com funções relacionadas, uma vez que downstream à região 3’ deste foi identificada uma segunda janela aberta de leitura correspondente a uma proteína da superfamília de fatores de transcrição contendo o domínio Zn2-Cys6, identificado como clft1. A análise do promotor do gene mfs1 revelou um putativo cis elemento de reconhecimento por proteínas desta família, o que sugere que esta proteína possa estar relacionada à regulação da expressão de mfs1. A técnica de Split- Marker mostrou-se eficiente na inativação do gene mfs1 de C. lindemuthianum, possibilitando o estudo da função do gene mfs1, em um mutante com integração específica e livre de integrações ectópicas. O mutante Δmfs1 não mostrou diferenças no perfil de sensibilidade a drogas comumente empregadas no controle da antracnose e em relação à patogenicidade, o mutante induziu mais precocemente os sintomas em folhas de feijoeiro susceptível, evidenciando uma situação de estresse decorrente da ausência do produto gênico. Foi observado também que o gene mfs1 exerce um papel primordial na manutenção da viabilidade celular de C. lindemuthianum, fato este confirmado pela conidiação alterada e pela confirmação de que este gene codifica para um transportador de membrana específico no transporte de hexoses, especificamente glicose, manose e frutose, uma vez que o mutante Δmfs1 mostrou crescimento reduzido quando cultivado em meios contendo apenas glicose, manose e frutose como fontes de carbono. A análise filogenética da proteína Mfs1 associada aos outros resultados obtidos nos sugere que este transportador é um membro da família SP, e que as proteínas MFS estão fortemente relacionadas com o tipo de substância que é transportada. Estudos de natureza básica sobre transportadores MFS são importantes para ampliar os conhecimentos sobre estas proteínas e a viabilidade celular em C. lindemuthianum.

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