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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

Transcriptome and Proteome Analysis using Signature Tags

Agaton, Charlotta January 2003 (has links)
<p>With the full sequence of the human genome now available, anexciting era in biomedical research has started. The sequenceprovides information about all our genes and greatly increasesthe scope to compare genetic activities in different cells, toanalyze genetic variation between individuals and betweendifferent species and, most importantly, to investigatesystematically the whole genome in a gene-by-gene manner, andthus increase our understanding of gene function.</p><p>This thesis describes studies in which developments weremade in several areas of functional genomics. Messenger RNAlevels were analyzed by the use of an amplification procedure,in which the 3´-ends of the transcripts were selected inorder to amplify the mRNA population in an unbiased fashion. Bysonicating cDNA originating from expressed mRNA, uniformlysized representatives of the transcripts,“signaturetags”, were obtained. The mRNA levels in the original mRNApopulation correlated well with the levels in the amplifiedmaterial, as verified by microarray analysis and realtimequantitative PCR. The expressed transcripts can be identifiedusing pyrosequencing, by comparing the obtained sequenceinformation from the signature tags to information contained invarious sequence databases. In one of the articles, the use ofpyrosequencing is illustrated by efforts to find genes involvedin the disease progression of atherosclerosis.</p><p>More challenging than the study of mRNA levels is to analyzewhen, where and how proteins fulfill their wide-ranging rolesin all the various cellular processes. Proteins are morecomplex biomolecules than mRNA, each having unique properties.Current techniques for studying proteins need much improvement,and are often limited to investigations of a specific portionof the proteome. One approach for studying the whole proteomeis to systematically generate reagents with specific affinityfor the proteins encoded by the genome, one by one. Theaffinity reagents can be used as flags for their targets,providing a flag-specific detection system, so that the targetproteins can be sub-cellularly localized in the majority ofhuman tissues in an array format. One of the articles includedin the thesis presents a pilot project for large-scale affinityreagent production. The aim was to provide a sound basis forwhole proteome studies, but as a pilot study this investigationwas limited to the proteins encoded by human chromosome 21. Allputative genes on the chromosome were subjected to antibodygeneration in a systematic manner. Small, uniform, and easilyproduced representative portions of the full-length proteinswere expressed. These were denoted“Protein EpitopeSignature Tags”and were designed to be unique for theirfull-length counterparts. The antibodies were produced inrabbits and two of the articles in the thesis discuss differentapproaches for affinity purification of the antibodies toachieve the highest possible specificity towards the targets.The resulting“mono-specific”, but still“multi-epitope”, antibodies can be used for a widerange of additional biochemical studies, such as protein arrayand protein pull-out analyses.</p><p><b>Keywords:</b>functional genomics, 3´-end signaturetags, pyrosequencing, amplification, PrEST, chromosome 21,polyclonal antibodies, dual expression, affinitypurification.</p>
12

Efeito de diferentes dosagens do preparado de anticorpos policlonais específicos sobre as variáveis ruminais, degradabilidade in situ e digestibilidade in vivo de bovinos alimentados com dieta de alto concentrado

Bastos, João Paulo Sigolo Teixeira [UNESP] 07 December 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-07Bitstream added on 2014-06-13T20:17:03Z : No. of bitstreams: 1 bastos_jpst_me_botfmvz.pdf: 410858 bytes, checksum: 65d4c4f6f1d9565cc9e57b146657bfd7 (MD5) / Universidade Estadual Paulista (UNESP) / O objetivo do presente estudo foi avaliar os efeitos de diferentes doses do preparado de anticorpos policlonais (PAP) produzido contra diferentes cepas de bactérias ruminais sobre parâmetros de fermentação ruminal (pH, AGCC, nitrogênio amoniacal e lactato) em bovinos recebendo dieta de alto concentrado. Foram utilizadas oito fêmeas bovinas, canuladas no rúmen, alimentadas (ad libitum) duas vezes ao dia com dieta de alto concentrado. O delineamento experimental utilizado foi o quadrado latino 4 x 4, replicado duas vezes. Os quatro tratamentos foram estruturados de acordo com as diferentes doses do produto (T1: 0,0 g/animal/dia, “controle”; T2: 1,5 g/animal/dia; T3: 3,0 g/animal/dia e T4: 4,5 g/animal/dia) e em diferentes períodos experimentais. Cada período experimental foi constituído de 21 dias, sendo que as colheitas de líquido ruminal foram realizadas a cada duas horas nos tempos de 0 a 12 horas, após a alimentação, no último dia de cada período e posteriormente analisadas. Não foi observado efeito de interação entre tempo e tratamento (p > 0,05) para os dados de pH. Independentemente do tempo de amostragem, não foi observado efeito linear ou quadrático dos níveis de administração do PAP sobre o pH ruminal. Não foram observados efeitos significativos (p > 0,05) sobre a concentração de AGCC total, nitrogênio amoniacal ou proporções molares dos ácidos acético, propiônico e butírico e lactato. Também não foram observados efeitos nos parâmetros de degradabilidade in situ para as três diferentes fontes alimentares utilizadas e para os valores de digestibilidade in vivo. Com isso, pode-se concluir que as diferentes doses do PAP não foram suficientes para alterar o ambiente ruminal sendo necessária à realização de mais testes que refutem ou não essa resposta. / Due the prohibition of antibiotics in ruminants diets arouse the necessity to find new alternatives for ionophores utilization without hazard to human health. The objective of the present study was to evaluate the effects of different doses of polyclonal antibody preparation (PAP) on ruminal fermentation parameters (pH, short chain fatty acids, ammonia nitrogen and lactate) in cattle fed high concentrate diets. Eight rumen cannulated cows were used in a latin square 4x4, twice replicated. The treatments were T1: 0.0 g/animal/day, “control”; T2: 1.5 g/animal/day; T3: 3.0 g/animal/day; T4: 4.5 g/animal/day with four experimental periods with 21 days each. Sample collection was carried out at the last day of each period with two hours of interval between each collection. There was no interaction between time and treatment (p > 0.05) for pH data. Independently from time of sampling there was no linear or quadratic effect on total short chain fatty acids (tSCFA), ammonia nitrogen (NH3-N) or molar proportion of acetate, propionate and butirate. There were no significant differences to degradability and digestibility values in this trial. Thus, it can be concluded that different levels of PAP were not sufficient to alter rumen environment with the necessity of more studies to validate or not this observation.
13

Efeito de diferentes dosagens do preparado de anticorpos policlonais específicos sobre as variáveis ruminais, degradabilidade in situ e digestibilidade in vivo de bovinos alimentados com dieta de alto concentrado /

Bastos, João Paulo Sigolo Teixeira, 1983- January 2009 (has links)
Orientador: Mário de Beni Arrigoni / Banca: Paulo Henrique Mazza Rodrigues / Banca: Rafael da Costa Cervieri / Resumo: O objetivo do presente estudo foi avaliar os efeitos de diferentes doses do preparado de anticorpos policlonais (PAP) produzido contra diferentes cepas de bactérias ruminais sobre parâmetros de fermentação ruminal (pH, AGCC, nitrogênio amoniacal e lactato) em bovinos recebendo dieta de alto concentrado. Foram utilizadas oito fêmeas bovinas, canuladas no rúmen, alimentadas (ad libitum) duas vezes ao dia com dieta de alto concentrado. O delineamento experimental utilizado foi o quadrado latino 4 x 4, replicado duas vezes. Os quatro tratamentos foram estruturados de acordo com as diferentes doses do produto (T1: 0,0 g/animal/dia, "controle"; T2: 1,5 g/animal/dia; T3: 3,0 g/animal/dia e T4: 4,5 g/animal/dia) e em diferentes períodos experimentais. Cada período experimental foi constituído de 21 dias, sendo que as colheitas de líquido ruminal foram realizadas a cada duas horas nos tempos de 0 a 12 horas, após a alimentação, no último dia de cada período e posteriormente analisadas. Não foi observado efeito de interação entre tempo e tratamento (p > 0,05) para os dados de pH. Independentemente do tempo de amostragem, não foi observado efeito linear ou quadrático dos níveis de administração do PAP sobre o pH ruminal. Não foram observados efeitos significativos (p > 0,05) sobre a concentração de AGCC total, nitrogênio amoniacal ou proporções molares dos ácidos acético, propiônico e butírico e lactato. Também não foram observados efeitos nos parâmetros de degradabilidade in situ para as três diferentes fontes alimentares utilizadas e para os valores de digestibilidade in vivo. Com isso, pode-se concluir que as diferentes doses do PAP não foram suficientes para alterar o ambiente ruminal sendo necessária à realização de mais testes que refutem ou não essa resposta. / Abstract: Due the prohibition of antibiotics in ruminants diets arouse the necessity to find new alternatives for ionophores utilization without hazard to human health. The objective of the present study was to evaluate the effects of different doses of polyclonal antibody preparation (PAP) on ruminal fermentation parameters (pH, short chain fatty acids, ammonia nitrogen and lactate) in cattle fed high concentrate diets. Eight rumen cannulated cows were used in a latin square 4x4, twice replicated. The treatments were T1: 0.0 g/animal/day, "control"; T2: 1.5 g/animal/day; T3: 3.0 g/animal/day; T4: 4.5 g/animal/day with four experimental periods with 21 days each. Sample collection was carried out at the last day of each period with two hours of interval between each collection. There was no interaction between time and treatment (p > 0.05) for pH data. Independently from time of sampling there was no linear or quadratic effect on total short chain fatty acids (tSCFA), ammonia nitrogen (NH3-N) or molar proportion of acetate, propionate and butirate. There were no significant differences to degradability and digestibility values in this trial. Thus, it can be concluded that different levels of PAP were not sufficient to alter rumen environment with the necessity of more studies to validate or not this observation. / Mestre
14

Vliv interferonu gama (IFN-\recke{gamma})a specifických polyklonálních protilátek na průběh experimentální perorální infekce \kur{Encephalitozoon cuniculi in vivo} / The influence of interferon gamma and specific antibodies on the p.o. infection with \kur{Encephalitozoon cuniculi in vivo}

JELÍNEK, Jiří January 2007 (has links)
The influence of interferon gamma and specific antibodies on the infection with E. cuniculi in vivo has been studied. Reconstruction of SCID mice with CD4+ T-lymphocytes from BALB/c mice and from mice with defect gene for interferon gamma was used. Effects of the treatment with mouse recombinant interferon gamma and anti-E. cuniculi sera on survival of E. cuniculi infected SCID mice were monitored. The influence of the immunization with E. cuniculi antigen on the survival of E. cuniculi infected mice with defect gene for interferon gamma was examined.
15

Efeito da Tensão de Oxigênio e da Densidade de Oócitos na Maturação In Vitro de Oócitos Bovinos e a Relação com o Estresse Oxidativo / Effect of Oxygen Tension and Oocyte Density Utilized on In Vitro Maturation of Bovine Oocytes and the Relationship with the Oxidative Stress

Giotto, Angelo Bertani 02 August 2013 (has links)
Submitted by Sandro Camargo (sandro.camargo@unipampa.edu.br) on 2015-03-08T18:55:13Z No. of bitstreams: 1 117110032.pdf: 700015 bytes, checksum: 794f9c0fa96f18e2200227f043531c61 (MD5) / Made available in DSpace on 2015-03-08T18:55:13Z (GMT). No. of bitstreams: 1 117110032.pdf: 700015 bytes, checksum: 794f9c0fa96f18e2200227f043531c61 (MD5) Previous issue date: 2013-08-02 / A maturação in vitro (MIV) é um dos pontos críticos da produção in vitro de embriões bovinos, sendo que vários fatores podem interferir na MIV, como a tensão de oxigênio e a densidade de oócitos por volume de meio. O objetivo deste estudo foi avaliar o efeito da tensão de oxigênio associada a diferentes densidades de oócitos durante a MIV. Para tanto, três experimentos foram conduzidos com oócitos bovinos obtidos de ovários de abatedouro. O experimento I consistiu na avaliação da maturação citoplasmática e nuclear, o experimento II na avaliação da produção de espécies reativas de oxigênio (ROS) e atividade antioxidante, e o experimento III na avaliação das taxas de fecundação in vitro. Após a seleção, os oócitos foram submetidos a MIV distribuídos aleatoriamente em 4 tratamentos: Tratamento 1:10/5%: 1 oócito em 10μl de meio de MIV em 5% de O 2 ; Tratamento 1:10/20%: 1 oócito em 10μl de meio em 20% de O 2 ; Tratamento 1:20/5%: 1 oócito em 20μl em 5% de O 2 e Tratamento 1:20/20%: 1 oócito em 20μl de meio em 20% de O 2 . A MIV foi conduzida em grupos de 15 oócitos em meio TCM 199 modificado, acrescido de FSH, LH, EGF, soro de égua em estro (SEE) e piruvato por 24h. Decorrido o período de MIV foi conduzida a fecundação in vitro em gotas de 300μl de meio Fert-TALP, sendo realizada pelo co-cultivo de oócitos e espermatozóides (2x10 6 sptz/mL) selecionados por gradientes de mini-Percoll por 18h. No experimento I, as taxas de maturação nuclear (69,66%) e maturação citoplasmática (71,55%) foram similares entre os tratamentos (P>0,05). No experimento II, a produção de ROS foi avaliada nos oócitos e no meio de MIV, assim como a atividade antioxidante foi avaliada após 24 h de MIV. A produção de ROS pelos oócitos foi superior nos tratamentos com baixa tensão de oxigênio (5%; 13,3UF) em relação a alta tensão de oxigênio (20%; 7,0UF) independentemente da densidade de oócitos (P<0,05). Os níveis de ROS detectados no meio de MIV foram superiores nos tratamentos com alta densidade de oócitos (1:10) independentemente da tensão de oxigênio (P<0,05). A atividade da SOD (21,3UI) e os níveis de GSH (6,95 nmol GSH/ml) mensurados nos oócitos foram similares entre os tratamentos (P>0,05). As taxas de fecundação e penetração foram superiores nos tratamentos com 20% de O 2 e com alta densidade de oócitos (1:10; 48,8%) em relação aos tratamentos 1:10/5% (29,5%) e 1:20/20% (29,1%; P<0,05). Adicionalmente a taxa de polispermia foi maior no tratamento com alta tensão de oxigênio e baixa densidade de oócitos. (1:20/20%; 27.8%) em relação ao tratamento 1:10/20% (13,41%; P<0,05). Os resultados deste estudo mostram interação entre a tensão de oxigênio e a densidade de oócitos aumentando a produção de ROS em determinadas associações e influenciando posteriormente as taxas de fecundação in vitro de oócitos bovinos. / The in vitro maturation is one of the critical points on in vitro production of bovine embryos so many factors can do an interference on IVM, like oxygen tension and oocyte density by volume of medium. The aim of this study was evaluate the effects of association of oxygen tension with different oocyte density during IVM Three experiments were performed with bovine oocytes obtained from abattoir ovaries, on experiment I was performed the nuclear and cytoplasmic evaluation, on the experiment III the biochemical assay of ROS production and antioxidant activity and on experiment III was realized the evaluation of in vitro fertilization. After selection, the oocytes were randomly distributed in 4 treatments: Treatment 1:10/5%: 1:10µl in 5% of O2; Treatment 1:10/20%: 1:10µl in 20% of O2; Treatment 1:20/5%: 1:20µl in 5% of O2; Treatment 1:20/20%: 1:20µl in 20% of O2. The IVM was performed in droplets (150µl or 300µl) of TCM 199 plus FSH, LH, EGF, EMS and pyruvate. The IVF were performed in droplets (300µl) of Fert-TALP. Was realized IVF with oocytes and spermatozoa (2x106 sptz/mL) selected by Percoll density gradients for 18h. On experiment I, the nuclear maturation rates (69.66%) and reorganization mitochondrial (71.55%) rates were similar among treatments (P>0.05). In Experiment II, the ROS production in oocytes, IVM medium and antioxidant activity were evaluated after 24 h of IVM. ROS production in oocytes was higher on treatments with low tension (5%; 13.3 UF) than 20% oxygen tension (7.0 UF) independently of oocyte density (P<0.05). ROS levels on IVM medium was higher on treatments with high oocyte density (1:10) independently of oxygen tension (P<0.05). The GSH levels (6.95 nmol GSH/ml) and SOD activity (21.3UI) were similar among treatments (P>0.05). The rates of normal fertilization and normal penetration were higher in treatments with 20% of O2 with high oocyte density (1:10;48.8%) than treatments 1:10/5% (29.5%) and 1:20/20% (29.1%; P<0.05). In addiction the polysperm rates were higher on treatment with high oxygen tension and low oocyte density (1:20/20%; 27.8%) than treatment 1:10/20% (13.4%; P<0.05). The results of this study show an interaction between oxygen tension and oocyte density, that increase ROS production on certain associations and subsequently affects the IVF rates. / The viruses are significant important pathogenic agents of several animal species, including cattle. In Brazil, several viral agents causing infections have been described in cattle and they produce significant economic losses. The identification of animals infected by a virus can be performed in different ways; however, definitive confirmation requires demonstration of the agent or immune response. For this purpose, various methods with the capacity to detect the viral particle, biological activity, genome, viral antigens, or specific immune response have been developed. Immunoassays are widely used in laboratory routine for detection of viral antigens in clinical or research. These assays exhibit good sensitivity, specificity and easy for implantation. The immunoassay methodologies are based on the employment of monoclonal or polyclonal antibodies specific to the viral antigens. Therefore, the aim of this study was to produce polyclonal antibodies for some bovine virus, and evaluate their reactivity in immunofluorescence, immunoperoxidase and slot blot tests. For this purpose, strains and/or isolates of bovine herpesvirus type 1 (BoHV-1), bovine herpesvirus type 2 (BoHV-2), bovine herpesvirus type 5 (BoHV-5), bovine herpesvirus type 5 gE deleted (BoHV-5 gEΔ), bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV), bluetongue virus (BTV), and vaccinia virus (VACV) were amplified in cell culture and the supernatant were used to immunize rabbits. The animals were immunized five times by the subcutaneous route, and five days after the last boost the blood was collected. The serum was obtained by centrifugation. The serum was diluted (1:100 a 1:204.800) and used as primary antibodies in the immunofluorescence, immunoperoxidase and slot blot assays. The working dilution was selected among those produced specific reaction with infected cells and absent or weak background in control cells. The antiserum showed higher reactivity in immunoperoxidase technique than the immunofluorescence and slot blot. The antiserum of the BoHV-1, BoHV-5, BVDV and BRSV presented the reactivity when tested with heterologous isolates in immunofluorescence, immunoperoxidase assays. In summary, that the polyclonal antibodies raised in rabbits have high concentrations of specific antibodies, which were demonstrated by the reactivity in immunofluorescence, immunoperoxidase and slot blot assays. Additionally, these reagents can be considered an important tool for the detection and characterization of various bovine viruses in diagnostic and research routine.
16

Desenvolvimento de um teste rápido de aglutinação em látex para o diagnóstico de Escherichia coli enteropatogênica e Escherichia coli produtora da toxina de Shiga / Development of a rapid latex agglutination test for the diagnosis of enteropathogenic Escherichia coli and Shiga toxin-producing Escherichia coli

Santos, Anna Raquel Ribeiro dos 09 May 2014 (has links)
Globalmente ocorrem cerca de 800.000 mortes de crianças menores de cinco anos associadas à diarreia, principalmente na África subsaariana, sul da Ásia e América Latina. Dentre os patógenos causadores de diarreia, Escherichia coli diarreiogênica (DEC) é o agente etiológico bacteriano mais comum, incluindo E. coli enteropatogênica (EPEC) e E. coli produtora da toxina de Shiga e seu subgrupo enterohemorrágica (STEC/EHEC). Os dados epidemiológicos indicam a importância do diagnóstico precoce e sua realização em locais com pouca infraestrutura. Desta forma o objetivo deste trabalho foi o desenvolvimento de um teste rápido, sensível e específico para o diagnóstico de EPEC e STEC/EHEC. Primeiramente, foram definidas diferentes condições do cultivo bacteriano: Dulbecco\'s modified Eagle\'s (DMEM), DMEM contendo 1% de triptona e DMEM pré-condicionado para o cultivo dos isolados de EPEC/EHEC e avaliação da produção/secreção das proteínas secretadas EspA e EspB, utilizando anticorpos monoclonais (MAb) e policlonais (PAb) anti-EspA ou anti-EspB por ELISA indireto. Para a avaliação da liberação das toxinas de Shiga para o sobrenadante do cultivo bacteriano de STEC/EHEC, foram testados diferentes condições de tratamento, o cultivo bacteriano foi tratado com Triton X-100 e o sedimento foi tratado com tampão de lise B-PER utilizando MAb e PAb anti-Stx1 ou anti-Stx2 por ELISA de captura. Subsequentemente, foi desenvolvido e avaliado o teste de aglutinação em látex para a detecção de EspB em isolados de EPEC/EHEC, e Stx1 e Stx2 em isolados de STEC/EHEC. EspB foi definida como biomarcador, o MAb anti-EspB como ferramenta para o diagnóstico de EPEC/EHEC, e a condição ideal para a produção/secreção de EspB foi o cultivo em DMEM. Para o diagnóstico de STEC/EHEC a condição ideal para liberação das toxinas Stx foi o tratamento do cultivo com Triton X-100. Tanto o ELISA, como a aglutinação em látex apresentaram sensibilidades e especificidades exigidas para testes diagnósticos de doenças negligenciadas em países em desenvolvimento e os testes de aglutinação em látex para a detecção destes patógenos foram precisos, rápidos e fáceis de executar, sendo portanto promissores para a utilização em laboratórios com mínima infraestrutura. / There are 800,000 deaths associated with diarrhea worldwide in children under five, and these are mainly in sub-Saharan Africa, Southeast Asia and Latin America. Among the causative pathogens of diarrhea, diarrheagenic Escherichia coli (DEC) is the most common bacterial etiological agent, including enteropathogenic E. coli (EPEC) and Shiga toxin-producing E. coli and its subgroup enterohemorrhagic E. coli (STEC/EHEC). Epidemiological data indicate the importance of early diagnosis and its realization in places with limited resources. Therefore, the objective of this work was to develop a rapid, sensitive and specific test for the diagnosis of EPEC and STEC/EHEC. First, different bacterial growth conditions were evaluated: Dulbecco\'s modified Eagle\'s medium (DMEM) or DMEM containing 1% tryptone, and DMEM pre-conditioned with EPEC/EHEC isolates. The production/secretion of the secreted proteins EspA and EspB was determined by indirect ELISA utilizing anti-EspA or anti-EspB monoclonal (MAb) and polyclonal (PAb) antibodies. Different treatments were tested for their effect on the release of Shiga toxins into the medium of STEC/EHEC bacterial cultures. The bacterial culture supernatant was treated with Triton X-100, and the sediment was treated with B-PER lysis buffer. The toxins release was determined by capture ELISA using anti-Stx1 or anti-Stx2 MAb and PAb. Subsequently, a latex agglutination test was developed and evaluated for the detection of EspB in EPEC/EHEC isolates and of Stx1 and Stx2 in STEC/EHEC isolates. EspB was defined as the biomarker and anti-EspB MAb as the tool for the diagnosis of EPEC/EHEC. The ideal conditions for the production/secretion of EspB were cultivation in DMEM. For the diagnosis of STEC/EHEC, the ideal conditions for the release of Stx were Triton X-100 treatment. ELISA as well as latex agglutination showed the sensitivities and specificities required for diagnostic tests of neglected diseases in developing countries. The latex agglutination test for the detection of these pathogens was precise, rapid and easy to perform, thereby being promising for their utilization in laboratories with limited resources.
17

Desenvolvimento de um teste rápido de aglutinação em látex para o diagnóstico de Escherichia coli enteropatogênica e Escherichia coli produtora da toxina de Shiga / Development of a rapid latex agglutination test for the diagnosis of enteropathogenic Escherichia coli and Shiga toxin-producing Escherichia coli

Anna Raquel Ribeiro dos Santos 09 May 2014 (has links)
Globalmente ocorrem cerca de 800.000 mortes de crianças menores de cinco anos associadas à diarreia, principalmente na África subsaariana, sul da Ásia e América Latina. Dentre os patógenos causadores de diarreia, Escherichia coli diarreiogênica (DEC) é o agente etiológico bacteriano mais comum, incluindo E. coli enteropatogênica (EPEC) e E. coli produtora da toxina de Shiga e seu subgrupo enterohemorrágica (STEC/EHEC). Os dados epidemiológicos indicam a importância do diagnóstico precoce e sua realização em locais com pouca infraestrutura. Desta forma o objetivo deste trabalho foi o desenvolvimento de um teste rápido, sensível e específico para o diagnóstico de EPEC e STEC/EHEC. Primeiramente, foram definidas diferentes condições do cultivo bacteriano: Dulbecco\'s modified Eagle\'s (DMEM), DMEM contendo 1% de triptona e DMEM pré-condicionado para o cultivo dos isolados de EPEC/EHEC e avaliação da produção/secreção das proteínas secretadas EspA e EspB, utilizando anticorpos monoclonais (MAb) e policlonais (PAb) anti-EspA ou anti-EspB por ELISA indireto. Para a avaliação da liberação das toxinas de Shiga para o sobrenadante do cultivo bacteriano de STEC/EHEC, foram testados diferentes condições de tratamento, o cultivo bacteriano foi tratado com Triton X-100 e o sedimento foi tratado com tampão de lise B-PER utilizando MAb e PAb anti-Stx1 ou anti-Stx2 por ELISA de captura. Subsequentemente, foi desenvolvido e avaliado o teste de aglutinação em látex para a detecção de EspB em isolados de EPEC/EHEC, e Stx1 e Stx2 em isolados de STEC/EHEC. EspB foi definida como biomarcador, o MAb anti-EspB como ferramenta para o diagnóstico de EPEC/EHEC, e a condição ideal para a produção/secreção de EspB foi o cultivo em DMEM. Para o diagnóstico de STEC/EHEC a condição ideal para liberação das toxinas Stx foi o tratamento do cultivo com Triton X-100. Tanto o ELISA, como a aglutinação em látex apresentaram sensibilidades e especificidades exigidas para testes diagnósticos de doenças negligenciadas em países em desenvolvimento e os testes de aglutinação em látex para a detecção destes patógenos foram precisos, rápidos e fáceis de executar, sendo portanto promissores para a utilização em laboratórios com mínima infraestrutura. / There are 800,000 deaths associated with diarrhea worldwide in children under five, and these are mainly in sub-Saharan Africa, Southeast Asia and Latin America. Among the causative pathogens of diarrhea, diarrheagenic Escherichia coli (DEC) is the most common bacterial etiological agent, including enteropathogenic E. coli (EPEC) and Shiga toxin-producing E. coli and its subgroup enterohemorrhagic E. coli (STEC/EHEC). Epidemiological data indicate the importance of early diagnosis and its realization in places with limited resources. Therefore, the objective of this work was to develop a rapid, sensitive and specific test for the diagnosis of EPEC and STEC/EHEC. First, different bacterial growth conditions were evaluated: Dulbecco\'s modified Eagle\'s medium (DMEM) or DMEM containing 1% tryptone, and DMEM pre-conditioned with EPEC/EHEC isolates. The production/secretion of the secreted proteins EspA and EspB was determined by indirect ELISA utilizing anti-EspA or anti-EspB monoclonal (MAb) and polyclonal (PAb) antibodies. Different treatments were tested for their effect on the release of Shiga toxins into the medium of STEC/EHEC bacterial cultures. The bacterial culture supernatant was treated with Triton X-100, and the sediment was treated with B-PER lysis buffer. The toxins release was determined by capture ELISA using anti-Stx1 or anti-Stx2 MAb and PAb. Subsequently, a latex agglutination test was developed and evaluated for the detection of EspB in EPEC/EHEC isolates and of Stx1 and Stx2 in STEC/EHEC isolates. EspB was defined as the biomarker and anti-EspB MAb as the tool for the diagnosis of EPEC/EHEC. The ideal conditions for the production/secretion of EspB were cultivation in DMEM. For the diagnosis of STEC/EHEC, the ideal conditions for the release of Stx were Triton X-100 treatment. ELISA as well as latex agglutination showed the sensitivities and specificities required for diagnostic tests of neglected diseases in developing countries. The latex agglutination test for the detection of these pathogens was precise, rapid and easy to perform, thereby being promising for their utilization in laboratories with limited resources.
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Estudo da resposta imune sistêmica em camundongos após inoculação por diferentes vias de imunização com Escherichia coli O86:H34 vivas ou mortas por formalina / Study of the systemic immune response in mice after inoculation by different routes of immunization with Escherichia coli O86:H34 alive or killed by formalin

Ana Patricia da Silva Oliveira 19 December 2001 (has links)
A Escherichia coli enteropatogênica (EPEC) é um dos principais agentes etiológicos da diarréia infecciosa tanto em crianças no primeiro ano de vida, como em adultos. As infecções por EPEC são prevalentes nos países em desenvolvimento, principalmente nas populações de baixo nível sócio-econômico, como as encontradas no Brasil. A resposta imune na infecção por EPEC permanece pobremente caracterizada. O uso das novas tecnologias no desenvolvimento de vacinas vem reforçar à importância de se levar em consideração a via natural de infecção do patógeno e utilizá-la como tema de estudo, quando se pretende estudar a resposta imune a um determinado agente infeccioso. O objetivo deste trabalho foi efetuar o estudo da resposta imune em animais inoculados com bactérias vivas ou mortas, por meio de diferentes vias de imunização. As bactérias em estudo foram: a cepa de E. coli O86:H34 e a cepa protótipo de E. coli O127:H6. A cepa de E. coli pertencente ao sorotipo O86:H34 foi isolada de fezes de crianças com diarréia. Foram empregadas as cepas : E2348/69, DH5&#945; e as mutantes E2348/69 flic-, E2348/69 &#916;tir, E2348/69 EscN-, CVD 206 &#916;eaeA, UMD 872 &#916;EspA, UMD 864 &#916;EspB, UMD 870 &#916;EspD. No presente estudo os camundongos BALB/c foram inoculados pela via intragástrica com a cepa de E. coli O86:H34 viva ou cepas O86:H34 e O127:H6 mortas por formol, que foram utilizadas nas imunizações pela via intragástrica e pela via intramuscular. Por meio de ELISA foram determinados os níveis de anticorpos específicos dos isotipos IgG, IgA e IgM, assim como o direcionamento da resposta imune para importantes antígenos que participam do mecanismo de patogenicidade da bactéria. De acordo com o perfil de reatividade no Immunoblot foi avaliada a especificidade dos anticorpos presentes nos soros imunes obtidos, frente aos antígenos de \"whole cells\" ou complexo de membrana externa bacteriana, empregados na técnica de \"immunoblotting\". A resposta imune a proteínas, como EspA, EspB, Tir, intimina, flagelos e BFP observada em camundongos, tem um importante papel no esclarecimento da infecção por este patógeno .Pela primeira vez foi realizado um estudo utilizando diferentes vias de imunização por EPEC em camundongos. Este estudo permitiu a análise de antígenos de E. coli reconhecidos pelos anticorpos produzidos pelas inoculações de bactérias vivas ou mortas por meio de vias intragástrica e intramuscular em camundongos, em comparação com aqueles reconhecidos na infecção natural ou experimental humana. Por conseguinte, os dados obtidos poderão auxiliar no esclarecimento desse complexo mecanismo de patogenicidade e orientar na seleção de peptídeos a serem utilizados no preparo de produtos vacinais específicos. / Enteropathogenic Escherichia coli is one of the major ethiologic agent that causes infectious diarrhoea in both infants and adults individuals. EPEC infections are prevalent in developing countries, mainly in low social-economic populations, as those found in Brazil. The immune response of this infection is still insufficiently known. Use of new technologies in the development of vaccines has been reinforced the importance of taking in account the natural route of infeccion of pathogens and use of it in investigation on immune response to be elicited against a certain to infectious agent. The aim of the present investigation was to study the immune response in mice inoculated with dead or alive bacteria, by means of diverse immunization routes. E. coli O86:H34 strain and E. coli O127:H6 prototype were employed for immunization. E. coli strain belonging to O86:H34 serotype was isolated from faeces from infants with diarrhoea. The strains: E2348/69, DH5 &#945; and the mutants strains E2348/69 flic-, E2348/69 &#916;tir, E2348/69 EscN-, CVD 206 &#916;eaeA, UMD 872 &#916;EspA, UMD 874 &#916;EspB, UMD 870 &#916;EspD were employed. BALB/c mice were inoculated by intragastric route with alive E. coli O86:H34 strain or formalin-killed O86:H34 and O127:H6 strains intragastric and intramuscular immunization routes. The specific antibodies of isotypes IgA, IgG and IgM were determinated by means of ELISA and the course of the immune response for important antigens that participate in the patogenicity mechanism of bacteria could be analysed. By means of reactivity profile on immunobloting, the specificity of antibodies present in obtained sera against whole cells or the outer membrane complex of the bacteria were analysed. Immune response to proteins like EspA, EspB, Tir, intimin, flagelin and BFP in immunized mice may have an important meaning for elucidation of infection in this pathogen At the first time a research using different routes of immunization with EPEC strains in mice has been conducted. This study allowed to compare antigens from E. coli recognized in natural or experimental human infection, and consequentently these data may help in the elucidation of this complex mechanism of pathogenicity, and also to orientate the selection of peptides to be used in preparation of specific vaccines.
19

Estudo da resposta imune sistêmica em camundongos após inoculação por diferentes vias de imunização com Escherichia coli O86:H34 vivas ou mortas por formalina / Study of the systemic immune response in mice after inoculation by different routes of immunization with Escherichia coli O86:H34 alive or killed by formalin

Oliveira, Ana Patricia da Silva 19 December 2001 (has links)
A Escherichia coli enteropatogênica (EPEC) é um dos principais agentes etiológicos da diarréia infecciosa tanto em crianças no primeiro ano de vida, como em adultos. As infecções por EPEC são prevalentes nos países em desenvolvimento, principalmente nas populações de baixo nível sócio-econômico, como as encontradas no Brasil. A resposta imune na infecção por EPEC permanece pobremente caracterizada. O uso das novas tecnologias no desenvolvimento de vacinas vem reforçar à importância de se levar em consideração a via natural de infecção do patógeno e utilizá-la como tema de estudo, quando se pretende estudar a resposta imune a um determinado agente infeccioso. O objetivo deste trabalho foi efetuar o estudo da resposta imune em animais inoculados com bactérias vivas ou mortas, por meio de diferentes vias de imunização. As bactérias em estudo foram: a cepa de E. coli O86:H34 e a cepa protótipo de E. coli O127:H6. A cepa de E. coli pertencente ao sorotipo O86:H34 foi isolada de fezes de crianças com diarréia. Foram empregadas as cepas : E2348/69, DH5&#945; e as mutantes E2348/69 flic-, E2348/69 &#916;tir, E2348/69 EscN-, CVD 206 &#916;eaeA, UMD 872 &#916;EspA, UMD 864 &#916;EspB, UMD 870 &#916;EspD. No presente estudo os camundongos BALB/c foram inoculados pela via intragástrica com a cepa de E. coli O86:H34 viva ou cepas O86:H34 e O127:H6 mortas por formol, que foram utilizadas nas imunizações pela via intragástrica e pela via intramuscular. Por meio de ELISA foram determinados os níveis de anticorpos específicos dos isotipos IgG, IgA e IgM, assim como o direcionamento da resposta imune para importantes antígenos que participam do mecanismo de patogenicidade da bactéria. De acordo com o perfil de reatividade no Immunoblot foi avaliada a especificidade dos anticorpos presentes nos soros imunes obtidos, frente aos antígenos de \"whole cells\" ou complexo de membrana externa bacteriana, empregados na técnica de \"immunoblotting\". A resposta imune a proteínas, como EspA, EspB, Tir, intimina, flagelos e BFP observada em camundongos, tem um importante papel no esclarecimento da infecção por este patógeno .Pela primeira vez foi realizado um estudo utilizando diferentes vias de imunização por EPEC em camundongos. Este estudo permitiu a análise de antígenos de E. coli reconhecidos pelos anticorpos produzidos pelas inoculações de bactérias vivas ou mortas por meio de vias intragástrica e intramuscular em camundongos, em comparação com aqueles reconhecidos na infecção natural ou experimental humana. Por conseguinte, os dados obtidos poderão auxiliar no esclarecimento desse complexo mecanismo de patogenicidade e orientar na seleção de peptídeos a serem utilizados no preparo de produtos vacinais específicos. / Enteropathogenic Escherichia coli is one of the major ethiologic agent that causes infectious diarrhoea in both infants and adults individuals. EPEC infections are prevalent in developing countries, mainly in low social-economic populations, as those found in Brazil. The immune response of this infection is still insufficiently known. Use of new technologies in the development of vaccines has been reinforced the importance of taking in account the natural route of infeccion of pathogens and use of it in investigation on immune response to be elicited against a certain to infectious agent. The aim of the present investigation was to study the immune response in mice inoculated with dead or alive bacteria, by means of diverse immunization routes. E. coli O86:H34 strain and E. coli O127:H6 prototype were employed for immunization. E. coli strain belonging to O86:H34 serotype was isolated from faeces from infants with diarrhoea. The strains: E2348/69, DH5 &#945; and the mutants strains E2348/69 flic-, E2348/69 &#916;tir, E2348/69 EscN-, CVD 206 &#916;eaeA, UMD 872 &#916;EspA, UMD 874 &#916;EspB, UMD 870 &#916;EspD were employed. BALB/c mice were inoculated by intragastric route with alive E. coli O86:H34 strain or formalin-killed O86:H34 and O127:H6 strains intragastric and intramuscular immunization routes. The specific antibodies of isotypes IgA, IgG and IgM were determinated by means of ELISA and the course of the immune response for important antigens that participate in the patogenicity mechanism of bacteria could be analysed. By means of reactivity profile on immunobloting, the specificity of antibodies present in obtained sera against whole cells or the outer membrane complex of the bacteria were analysed. Immune response to proteins like EspA, EspB, Tir, intimin, flagelin and BFP in immunized mice may have an important meaning for elucidation of infection in this pathogen At the first time a research using different routes of immunization with EPEC strains in mice has been conducted. This study allowed to compare antigens from E. coli recognized in natural or experimental human infection, and consequentently these data may help in the elucidation of this complex mechanism of pathogenicity, and also to orientate the selection of peptides to be used in preparation of specific vaccines.
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Entwicklung immunchemischer Methoden zur Spurenanalytik der Sprengstoffe Nitropenta und Trinitrotoluol

Hesse, Almut 04 May 2017 (has links)
Der Sprengstoff PETN ist äußerst schwer zu detektieren. Ein verbesserter anti-PETN-Antikörper wurde durch Anwendung des Bioisosterie-Konzepts entwickelt. Diese polyklonalen IgGs sind sehr selektiv und sensitiv. Die Nachweisgrenze des ELISAs beträgt 0,15 µg/L. Der Messbereich des Immunoassays liegt zwischen 1 und 1000 µg/L. Die Antikörper sind recht pH-stabil als auch robust gegen Lösungsmittelzusätze. Für die Umweltanalytik von TNT wurde eine HPLC-kompatible Affinitätssäule mit porösem Glas als Trägermaterial hergestellt. Um die anti-TNT-Antikörper selektiv aus den TNT-Seren zu isolieren, wurde eine Trennung an einer Dinitrophenyl-Affinitätssäule durchgeführt. Zur Optimierung der Kopplungsmethode wurden orangefarbene Dabsyl-Proteine synthetisiert und auf der Oberfläche gebunden. Die Färbung wurde als Indikator für die Ligandendichte verwendet. Wegen der hohen Affinitätskonstanten der anti-TNT-IgGs lässt sich TNT nicht reversibel von der TNT-Affinitätssäule eluieren. Daher wurde eine neuartige Elutionsmethode entwickelt, die thermische Online-Elution. Die maximale Kapazität einer TNT- Affinitätssäule betrug 650 ng TNT bzw. 10 µg/mL Säulenvolumen. Um die Ligandendichte der TNT-Affinitätssäulen zu bestimmen, wurde ein neues Verfahren entwickelt, da die spektroskopischen Proteinbestimmungsmethoden nicht geeignet waren. Zur Proteinbestimmung wurde eine HPLC-Trennung der Aminosäuren Tyr und Phe ohne vorherige Derivatisierung entwickelt. Die Proteinhydrolysezeit wurde durch Einsatz einer Mikrowelle von 22 h auf 30 min verkürzt. Zur internen Kalibrierung wurden HTyr und FPhe verwendet. Die Nachweisgrenze bei 215 nm ist sowohl für Tyr als auch für Phe 0,05 µM (~ 10 µg/L). Dieses neue Verfahren, das als Aromatische Aminosäureanalyse (AAAA) bezeichnet werden kann, wurde zur Proteinbestimmung von homogenen Proben mit NIST-BSA validiert, wobei die Nachweisgrenze für Proteine 16 mg/L (~ 300 ng BSA) ist. Die relative Standardabweichung incl. der Hydrolysestufe beträgt 5%. / The explosive Pentaerythritol tetranitrate (PETN) is extremely difficult to detect. An improved antibody against PETN was developed by using the bioisosteric concept. These polyclonal antibodies are highly selective and sensitive. The limit of detection (LOD) of the ELISA was determined to be 0.15 µg/L. The dynamic range of the assay was found to be between 1 and 1000 µg/L. The antibodies are sufficiently pH-stable and resistant to solvent additives. An HPLC-compatible TNT-affinity column with porous glass as support material was prepared for the environmental analysis. In order to isolate the anti-TNT antibodies of the TNT sera a separation was carried out on a dinitrophenyl-affinity column. To optimize the immobilization method, orange-coloured dabsyl proteins were synthesized and bound to the surface. The colour intensity was found to be an indicator for the immobilization rate. In consequence of the high affinity constants of the anti-TNT antibodies, TNT can''t elute by a typical acidic elution step. Therefore, a novel separation approach, the thermal online-elution was developed. The maximum capacity of an affinity column was 650 ng TNT or 10 µg/mL of column volume. To quantify the immobilization rate of proteins, a new method has been developed, because the usual protein determination methods were unsuitable. Therefore an HPLC separation method of Tyr and Phe was developed without prior derivatization. Two internal standard compounds, HTyr and FPhe, were used for calibration. The LOD was estimated to be 0.05 µM (~ 10 µg/L) for Tyr and Phe at 215 nm. The protein hydrolysis time was reduced from 22 h to 30 min using microwave technique. This procedure, that was termed aromatic amino acid analysis (AAAA), has been validated for protein determination of homogeneous samples with NIST-BSA. The LOD for proteins was calculated to be below 16 mg/L (~ 300 ng BSA absolute). The relative standard deviation, including the hydrolysis step, is 5%.

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