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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.
151

Caracterização da microbiota e efeito do preparo químico-mecânico e da medicação intracanal na redução de microrganismos, endotoxinas e citocinas pró-inflamatórias em dentes com insucesso do tratamento endodôntico e presença de lesão periapical / Characterization of microbiota and effect of chemo-mechanical preparation and intracanal medication in reducing microrganisms, endotoxins and proinflammatory cytokines in root-filled teeth persistent infection failure and the presence of apical periodontitis

Barbosa-Ribeiro, Marlos 1986- 02 June 2015 (has links)
Orientadores: Brenda Paula Figueiredo de Almeida Gomes, Caio Cezar Randi Ferraz / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-27T00:47:36Z (GMT). No. of bitstreams: 1 Barbosa-Ribeiro_Marlos1986-_M.pdf: 4792753 bytes, checksum: 592cb57914c07a67f1cf0d83a084cbe7 (MD5) Previous issue date: 2015 / Resumo: O conhecimento da comunidade microbiana e do seu potencial antigênico é importante para o entendimento da patogênese da periodontite apical em dentes endodonticamente tratados. Os objetivos do presente estudo foram: 1) Caracterizar a microbiota associada ao insucesso endodôntico através do teste bioquímico, Nested PCR e sequenciamento parcial do gene 16S rRNA; 2) Quantificar endotoxinas (LPS) por meio do teste Limulus Amebocyte Lysate (LAL) e citocinas pró-inflamatórias IL-1?, IL-1?, TNF-? e PGE2 através do ensaio imunoenzimático (ELISA), correlacionando-as com aspectos clínicos e radiográficos dos pacientes; 3) Avaliar o efeito do preparo químico-mecânico (PQM) e medicação intracanal (MIC) na redução de microrganismos, LPS e de citocinas pró-inflamatórias. Foram coletadas amostras do conteúdo endodôntico de 20 dentes unirradiculares antes (C1), após o PQM (C2), após o uso de EDTA 17% (C3) agitado com ultrassom, e após a MIC (C4). Utilizaram-se materiais estéreis e/ou apirogênicos e técnicas assépticas durante as coletas. Após o processamento laboratorial das amostras, os dados foram tabulados e analisados pelos testes estatísticos Qui-quadrado, Correlação de Spearman e ANOVA (Tukey-Kramer). Os resultados apontaram a presença de uma microbiota mista contendo bactérias Gram positivas e Gram negativas. Quatro diferentes filos foram identificados: Actinobacteria, Firmicutes, Fusobacteria e Proteobacteria. Enterococcus faecalis foi a espécie mais prevalente, identificada fenotipicamente (19/158) e genotipicamente (42/158). O sequenciamento conseguiu identificar 10,12% das amostras em nível de gênero e 89,88% em nível de espécie, enquanto que o teste bioquímico identificou 13,29% e 51,26%, respectivamente. As bactérias mais prevalentes identificadas por Nested PCR foram: Enterococcus faecalis (97,5%), seguido de Porphyromonas gingivalis (88,75%), Fusobacterium nucleatum (56,25%) e Aggregatibacter actinomycetemcomitans (37,5%). O PQM reduziu bactérias em 96,69% (p<0,05), com percentual de redução para Clorexidina (CLX) 2% gel em 99,3% e para NaOCl 6% em 92,1% (p>0,05). O EDTA 17% somente mostrou efeito complementar na redução bacteriana no grupo do NaOCl 6% (p<0,05). Apenas a CLX 2% gel foi efetiva na redução de endotoxinas comparado ao NaOCl 6% e EDTA 17% (P<0,05). O PQM, independentemente da substância química utilizada, foi efetivo na redução dos níveis das citocinas pró-inflamatórias Il-1? (88,14%), Il-1? (89,33%), TNF-? (89,85%) e PGE2 (48,60%) (p<0,05). A MIC não mostrou efeito aditivo na redução de bactérias e citocinas pró-inflamatórias em ambos os grupos (p<0,05); e somente apresentou ação sobre LPS no grupo Ca(OH)2 + CLX 2% gel (p<0,05). Houve correlação positiva ente bactérias, LPS, citocinas pró-inflamatórias e os aspectos clínicos e radiográficos dos pacientes (P<0,05). Conclui-se que o PQM apresentou efeito significante na redução do conteúdo infeccioso de canais radiculares de dentes com insucesso do tratamento endodôntico, enquanto que a MIC não mostrou efeito aditivo significante na redução desses níveis / Abstract: The knowledge of the microbial community and its antigenic potential is important for understanding the pathogenesis of apical periodontitis in endodontically treated teeth. The objectives of this study were: 1) Characterize the microbiota associated to endodontic failure through the biochemical test, Nested PCR and partial sequencing of gene 16S rRNA.; 2) Quantify endotoxin (LPS) by Limulus Amebocyte Lysate test and pro-inflammatory cytokines IL-1?, IL-1?, TNF-? and PGE2 by enzyme-linked immunosorbent assay, correlating them with the patients' clinical and radiographic features; 3) To evaluate the effect of chemo-mechanical preparation (CMP) and intracanal medications (ICM) in reducing microorganisms, LPS and pro-inflammatory cytokines. Samples of endodontic content of 20 single-rooted teeth were collected before (C1), after CMP (C2), after the use of 17% EDTA (C3) agitated with ultrasound, and after ICM (C4). Sterile/apyrogenic materials and a aseptic techniques were used during the samples' collection. After processing the samples, the data were tabulated and analyzed by statistical testes Chi-square, Spearman correlation, and analysis of variance (Tukey-Kramer). The results indicated the presence of a mixed microbiota presenting Gram positive and Gram negative bacteria. Four different phyla were identified: Actinobacteria, Firmicutes, Proteobacteria and Fusobacterium. Enterococcus faecalis was the most prevalent species, identified phenotypically (19/158) and genotypically (42/158). Sequencing was able to identify 10.12% of the samples at the genus level and 89.88% at the species level, whereas the biochemical test identified 13.29% and 51.26%, respectively. The most prevalent bacteria by Nested PCR were: Enterococcus faecalis (97.5%), followed by Porphyromonas gingivalis (88.75%), Fusobacterium nucleatum (56.25%) and Aggregatibacter actinomycetemcomitans (37.5%). CMP reduced bacteria in 96.69% (p<0.05), with a percentage reduction in 99.3% for 2% CLX gel and in 92.1% for 6% NaOCl (p>0.05). EDTA 17% showed only a further effect on bacterial reduction in the 6% NaOCl group (p<0.05). Only 2% CLX gel was effective in reducing endotoxin compared to 6% NaOCl and 17% EDTA (p<0.05). CMP regardless of chemical substance used, was effective in reducing the levels of pro-inflammatory cytokines IL-1? (88.14%), IL-1? (89.33%), TNF-? (89.85%) and PGE2 (48.60%) (p<0.05).The intracanal medication not show additive effect in reducing bacteria and proinflammatory cytokines in both groups (p<0.05); and only presented action against LPS in the Ca(OH)2 + 2% CLX gel group (p<0.05). There was a positive correlation between bacteria, LPS, pro-inflammatory cytokines and clinical and radiographic features (p<0.05). In conclusion, CMP presented a significant effect in reducing the infectious content of root canal of teeth with endodontic failure, while ICM showed no significant additive effect in reducing these levels / Mestrado / Endodontia / Mestre em Clínica Odontológica
152

Etude des déterminants de l'exposition aux nuisances agricoles et leurs effets sur le cancer du poumon / Occupational exposures in farming and lung cancer risk

Boulanger, Mathilde 03 June 2019 (has links)
Contexte. La population agricole française, dans son ensemble, présente un plus faible risque de Cancer BronchoPulmonaire (CBP) par rapport à la population générale. Ce constat, retrouvé au niveau international, s’explique au moins en partie par un tabagisme plus faible notamment chez les plus âgés et chez les femmes ; un effet « protecteur » des endotoxines est également suspecté. Néanmoins le milieu professionnel agricole peut exposer à de nombreux cancérogènes pulmonaires avérés ou suspectés ; malgré cela, à l’exception de certains secteurs d’élevage, il n’existe que très peu de données sur les associations entre expositions ou situations de travail précises en milieu agricole et le risque de CBP. Objectifs. Le premier objectif de ce travail de thèse était d’étudier les associations, au sein de la cohorte AGRICAN (AGRIculture et CANcer), entre (1) CBP et exposition aux activités et tâches de cultures ; (2) CBP et utilisation de pesticides arsenicaux et herbicides dinitroanilines, et de mettre à profit le nombre important de sujets inclus et de cas de CBP pour réaliser ces analyses par sous-type histologique. Le deuxième objectif était d’initier un projet de métrologie de divers aérocontaminants en milieu professionnel agricole. Méthodes. Les analyses ont été menées en utilisant les données de l’étudeAGRICAN et de la matrice culture-exposition aux pesticides PESTIMAT. Nous avons utilisé un modèle de Cox, ajusté sur le sexe, le tabagisme, les élevages bovin et équin. Le projet métrologique AirExpA s’est limité à la Normandie, avec mesures personnelles des poussières totales (en temps réel), endotoxines et 38 mycotoxines (en cumulé), en élevage bovin, lors des foins et des moissons de blé/orge et pois fourrager/féverole. Résultats et discussion. Nous avons retrouvé une association inverse entre l’activité de culture de maïs et le risque de CBP, une association positive entre adénocarcinomes et viticulture, ainsi qu’entre carcinomes à petites cellules et culture de pois fourragers/féveroles. Les éléments de plausibilité d’un lien entre ces secteurs d’activité et le risque de CBP sont encore des hypothèses : la culture de maïs, par le stockage du grain, pourrait exposer aux endotoxines ; à l’inverse, la récolte de pois fourragers a été décrite comme empoussiérante, mais cet élément doit être confirmé par une caractérisation des poussières. Nous n’avons pas retrouvé d’association entre utilisation de pesticides arsenicaux, ni de dinitroanilines, et risque de CBP ; cependant les analyses stratifiées sur le sexe et le statut tabagique, montraient des associations positives chez les non-fumeurs et chez les femmes (en particulier pour les adénocarcinomes). Enfin, le projet AirExpA a permis de documenter un gradient d’exposition aux poussières et endotoxines en fonction de différentes tâches en élevage bovin, et une exposition plus modérée mais réelle, aux endotoxines, lors des activités de culture. Les analyses de mycotoxines sont toutes revenues inférieures aux limites de quantification. L’analyse des pics d’exposition, l’étude d’autres aérocontaminants et d’autres secteurs agricoles, sont des perspectives de ce projet. Conclusion. Notre travail soulève de nouvelles questions de recherche quant à des associations possibles entre certaines expositions professionnelles en milieu agricole (cultures et tâches, utilisation de certains pesticides) et risque de CBP, et contribue à une meilleure connaissance des expositions professionnelles des agriculteurs aux aérocontaminants. / Background. Farmers are at lower risk of lung cancer, compared to the general population, at least partly because of a reduced rate of smoking among the elderly and women. A “protective” effect of endotoxins has also been hypothesized. Even though some of the occupational exposures occurring during farming-related activities are well-known or suspected lung carcinogens, there is scarce data in the literature, about the associations between specific occupational exposures or tasks in farming, and the risk of lung cancer. Objectives.The first aim was to analyse, in the AGRICAN cohort, the associations between lung cancer and (1) occupational exposure to various crops and related tasks; (2) arsenical pesticides and dinitroaniline herbicides use in farming. We also aimed at stratifying our analysis by histological subtypes of lung cancer. The second aim was to initiate a metrological project, to assess farmers’ occupational exposure to various airborne pollutants, in relation with the risk of lung cancer. Methods. We used the data from the French AGRIculture and CANcer cohort (AGRICAN) and from the PESTIcide MATrix project (PESTIMAT), to assess the associations between occupational farming exposures and lung cancer. A Cox model was performed, with adjustment on gender, smoking intensity, cattle and horses breeding. Our metrological project AirExpA was first launched in Normandy and focused on a few exposures – total dusts in real-time ; endotoxins and 38 mycotoxins, cumulative – in cattle breeding, wheat/barley and peas harvesting, and haymaking. Results and discussion. We reported a negative association between lung cancer and corn growing, and positive associations between (1) vineyard growing and adenocarcinoma; (2) peas growing and small cell lung cancer. Corn growing, especially grain handling, might expose to significant levels of endotoxins, thus explaining the inverse association. Peas growing, especially harvesting, is reportedly a dusty task; the AirExpA project will enable us to better characterize the dusts. We found no association between arsenicals use and lung cancer, nor with dinitroaniline herbicides use. However, stratifying on gender and smoking status showed positive associations among women and never-smokers, especially for adenocarcinomas. The AirExpA project showed dust and endotoxins exposure gradients in cattle breeding, depending on the task, and a mild but real exposure to endotoxins in various tasks in crop growing. All samples for mycotoxins were below the limit of quantification. Analysing exposure peaks, extending the project to other breedings/crops and air pollutants are among the perspectives. Conclusion. Our results raise new research questions about possible associations between occupational agricultural exposures and lung cancer, and contribute to a better knowledge and understanding of farmers’ occupational exposure to air pollutants.
153

Effects of proinflammatory agents on oxygen species production by bovine mammary epithelial and immune cells

Boulanger, Véronique. January 2000 (has links)
No description available.
154

Remoção de endotoxina presente em meio fermentado contendo biomoléculas utilizando sistemas micelares de duas fases aquosas / Endotoxin removal from fermentation broth containing biomolecules using two-phase micellar system

Lopes, André Moreni 20 August 2010 (has links)
Foi investigada a utilização de Sistema Micelar de Duas Fases Aquosas (SMDFA) para remoção de lipolissacarídeos (LPS) de preparações contendo proteínas recombinantes de interesse farmacêutico, como a proteína verde fluorescente (GFPuv). Os SMDFA são constituídos por soluções de tensoativos contendo micelas e oferecem ambientes hidrofóbico e hidrofílico, que possibilitam seletividade na partição de biomoléculas de acordo com sua hidrofobicidade, permitindo a remoção de LPS contaminante. Neste trabalho, foi realizada a implementação do método para a quantificação de LPS em amostras contaminadas e a obtenção de LPS e GFPuv puros a partir de cultivo de E. coli recombinante. Além disso, foi estudada a influência do Triton X-114 na metodologia de quantificação de LPS, e a adição de MgSO4, CaCl2, KI e (NH4)2SO4 na partição de GFPuv e LPS puros em SMDFA. E ainda, realizou-se um planejamento experimental (22) para avaliar os maiores KGFPuv e %RECGFPuv. O homogeneizado celular de E. coli foi testado nas melhores condições obtidas com o planejamento experimental. E finalmente, o processo por cromatografia de afinidade por íons metálicos (IMAC) foi empregado para investigar a adsorção de LPS em matriz IDA-Ca2+. Conforme os resultados obtidos, o TX-114 causou elevada interferência no método cinético cromogênico, em função da similaridade desta molécula com os LPS. Os LPS apresentaram partição preferencial para a fase concentrada em micelas, com altos valores de remoção, %REMLPS>98,0%. Ao contrário, a GFPuv foi recuperada preferencialmente na fase diluída, na qual existe maior volume disponível, resultando em valores de KGFPuv>1. A adição de sais ocasionou diminuição nos valores KGFPuv, provavelmente por causa da carga negativa que GFPuv adquiriu nas condições avaliadas. Os resultados do planejamento experimental mostraram que a melhor condição de partição obtida foi na região do ponto central, 4,0% (p/p) a 60,0°C, com KGFPuv>10. O processo por IMAC apresentou as maiores capacidades de adsorção de LPS-IDA-Ca+2 nas condições de menor pH e maior força iônica 4,0 e 1,0 mol/L, respectivamente. O processo de purificação por SMDFA empregado para a remoção de LPS contaminante presente em meio fermentado contendo GFPuv, demonstrou ser eficiente em recuperar a biomolécula-alvo na fase diluída e separar o principal contaminante na fase rica em micelas. Portanto, pode ser empregado como primeira etapa para a remoção de altas concentrações de LPS na purificação de proteínas hidrofílicas como a GFPuv. / The Aqueous Two-Phase Micellar System (ATPMS) was investigated for endotoxin (LPS) removal from preparations containing recombinant proteins of pharmaceutical interest, such as the green fluorescent protein (GFPuv). These systems usually consist of micellar surfactants solutions and offer both hydrophobic and hydrophilic environments, providing selectivity to the biomolecules partitioning according to its hydrophobicity. In this work, the implementation of the method for LPS quantification in contaminated samples was accomplished, as well as the obtaining of pure LPS and GFPuv from recombinant E. coli. Furthermore, the influence of Triton X-114 in the methodology for LPS quantification was studied, as the addition of MgSO4, CaCl2, KI, and (NH4)2SO4 into the partition of pure GFPuv and LPS in ATPMS. In addition, a statistical design (22) was carried out to evaluate the highest KGFPuv and %RECGFPuv. The E. coli cell lysate was tested under optimum conditions obtained with the statistical design. And, finally, the process by ionmetal affinity chromatography (IMAC) was used to investigate the adsorption of LPS in IDA-Ca2+ matrix. The results showed that the TX-114 caused high interference in the kinetic chromogenic method, according to the similarity of this molecule to LPS. The LPS showed preferential partitioning to the micellerich phase, with high values of removal, %REMLPS>98.0%. In the other hand, the GFPuv was preferentially recovered in the micelle-poor phase, in which there is greater volume available resulting in values of KGFPuv>1. The addition of salts caused a reduction in the values KGFPuv, probably because of the negative charge that the GFPuv acquired at the conditions evaluated. The results of the statistical design showed that the best partitioning condition obtained was in the central point region, 4.0% (wt/wt) at 60.0°C, with KGFPuv>10. The process by IMAC showed the highest adsorption of LPS-IDA-Ca+2 capacities at the conditions of lower pH and higher ionic strength 4.0 and 1.0 mol/L, respectively. The purification process for the LPS contaminant removal from E. coli fermentation containing GFPuv by ATPMS proved to be efficient in the recovering of target biomolecule in the micelle-poor phase, and separating the main contaminant in the micelle-rich phase. Furthermore, this system can be exploited as the first step for removal of higher LPS concentrations from hydrophilics protein purification.
155

Análises de genomas de Bacillus thuringiensis subsp. israelensis isolados em Tocantins com toxicidade para mosquitos de interesse em saúde pública

Alves, Giselly Batista 14 August 2017 (has links)
Bacillus thuringiensis subsp. israelensis é uma bactéria gram positiva, amplamente utilizada no controle de insetos Diptera, família Culicidae, tais como Aedes aegypti e Culex quinquefasciatus. O sequenciamento de genomas completos de estirpes de B. thuringiensis tem permitido a identificação e caracterização de proteínas inseticidas, assim como a realização de estudos de genômica comparativa, permitindo evidenciar diferenças funcionais e filogenéticas. Neste contexto, o presente estudo teve como objetivo realizar análises genômicas de quatro isolados de B. thuringiensis subsp. israelensis que apresentam diferentes toxicidades para larvas de A. aegypti e C. quinquefasciatus. O sequenciamento dos genomas dos isolados T0124, T0131, T0137 e T0139 foi realizado a partir da plataforma MiSeq-Ilumina, e a montagem e anotação foram feitas utilizando ferramentas do programa de bioinformática Geneious. As análises resultaram em cromossomos com tamanhos aproximados de 5.414 Kb, conteúdo G+C de 35,2% e 5.358 regiões codificantes. Com relação ao conteúdo extracromossomal, foram montados três plasmídeos menores de 5,4; 6,8 e 7,6 Kb, e três plasmídeos maiores de 127, 235 e 359 Kb para todos os isolados, e estes foram enumerados de 1 a 6. A anotação revelou que apenas os plasmídeos de número 4, que correspondem ao pBtoxis, possuem proteínas inseticidas, sendo elas Cry4Aa, Cry4Ba, Cry11Aa, Cry10Aa, Cyt1Aa, Cyt2Ba e Cyt1Ca. A análise comparativa entre os genomas demonstra que os cromossomos T0124, T0131, T0137 e T0139 apresentam sequências colineares e com 99% de identidade, e seus respectivos plasmídeos 1, 2, 3, 4, 5 e 6 compartilham todas as suas regiões codificantes, incluindo aquelas relacionadas a δ-endotoxinas. A comparação de sequências de enterotoxinas, metaloproteases e fosfolipases demonstra que estes também são conservados entre os genomas. Na análise filogenética, os cromossomos T0124, T0131, T0137 eT0139 agruparam-se juntamente com os genomas dos isolados AM65-52 e HD-789 disponíveis no GenBank, sugerindo uma estreita relação genética entre estirpes de B. thuringiensis subsp. israelensis. Os isolados T0124, T0131, T0137 e T0139 apresentam diferentes concentrações letais para larvas de A. aegypti e C. quinquefasciatus, e a adição de dados proteômicos aos dados genômicos, aqui obtidos, poderão auxiliar na compreensão destas diferenças de toxicidade. Contudo as análises comparativas entre os genomas dos isolados T0124, T0131, T0137 e T0139 mostram alto grau de conservação genética a nível de nucleotídeos de B. thuringiensis subsp. israelensis. / Bacillus thuringiensis subsp. israelensis is a gram-positive bacterium widely used to control insects of the order Diptera, such as Aedes aegypti (Diptera: Culicidae) and Culex quinquefasciatus (Diptera: Culicidae). The sequencing of complete genomes of B. thuringiensis strains has allowed the identification and characterization of insecticidal proteins, as well as the comparative genomic studies, allowing the identification of functional and phylogenetic differences. In this context, the present study aimed to perform genomic analysis of four isolates of B. thuringiensis subsp. israelensis having different toxicities for larvae of A. aegypti and C. quinquefasciatus larvae. Sequencing of genomes of the isolates T0124, T0131, T0137 and T0139 was performed from the MiSeq-Ilumina platform, and assembly and annotation were done using tools from the Geneious bioinformatics program. The analyzes resulted in chromosomes with approximate sizes of 5,414 Kb, G + C content of 35.2% and 5,358 coding regions. Regarding extrachromosomal content, three smaller plasmids of 5.4, 6.8 and 7.6 Kb, and three larger plasmids of 127, 235 and 359 Kb were assembled for all the isolates, and these were enumerated from 1 to 6. The annotation revealed that only the plasmids of number 4, corresponding to pBtoxis, possess insecticidal proteins, being Cry4Aa, Cry4Ba, Cry11Aa, Cry10Aa, Cyt1Aa, Cyt2Ba and Cyt1Ca. Comparative analysis between the genomes demonstrates that chromosomes T0124, T0131, T0137 and T0139 have collinear sequences and 99% identity, and their respective plasmids 1, 2, 3, 4, 5 and 6 share all of their coding regions, including those related to δ-endotoxins. Comparison of enterotoxin, metalloprotease and phospholipase sequences shows that these are conserved among the genomes. In the phylogenetic analysis, chromosomes T0124, T0131, T0137 and T0139 were grouped together with the genomes of the isolates AM65-52 and HD-789 available in GenBank, suggesting a close genetic relation between strains of B. thuringiensis subsp. israelensis. The isolates T0124, T0131, T0137 and T0139 present different lethal concentrations to larvae of A. aegypti and C. quinquefasciatus, and the addition of proteomic data to the genomic data obtained here may help to understand these differences in toxicity. However, the comparative analyzes between the genomes of isolates T0124, T0131, T0137 and T0139 show a high degree of genetic conservation at the nucleotide level of B. thuringiensis subsp. israelensis.
156

Remoção de endotoxina presente em meio fermentado contendo biomoléculas utilizando sistemas micelares de duas fases aquosas / Endotoxin removal from fermentation broth containing biomolecules using two-phase micellar system

André Moreni Lopes 20 August 2010 (has links)
Foi investigada a utilização de Sistema Micelar de Duas Fases Aquosas (SMDFA) para remoção de lipolissacarídeos (LPS) de preparações contendo proteínas recombinantes de interesse farmacêutico, como a proteína verde fluorescente (GFPuv). Os SMDFA são constituídos por soluções de tensoativos contendo micelas e oferecem ambientes hidrofóbico e hidrofílico, que possibilitam seletividade na partição de biomoléculas de acordo com sua hidrofobicidade, permitindo a remoção de LPS contaminante. Neste trabalho, foi realizada a implementação do método para a quantificação de LPS em amostras contaminadas e a obtenção de LPS e GFPuv puros a partir de cultivo de E. coli recombinante. Além disso, foi estudada a influência do Triton X-114 na metodologia de quantificação de LPS, e a adição de MgSO4, CaCl2, KI e (NH4)2SO4 na partição de GFPuv e LPS puros em SMDFA. E ainda, realizou-se um planejamento experimental (22) para avaliar os maiores KGFPuv e %RECGFPuv. O homogeneizado celular de E. coli foi testado nas melhores condições obtidas com o planejamento experimental. E finalmente, o processo por cromatografia de afinidade por íons metálicos (IMAC) foi empregado para investigar a adsorção de LPS em matriz IDA-Ca2+. Conforme os resultados obtidos, o TX-114 causou elevada interferência no método cinético cromogênico, em função da similaridade desta molécula com os LPS. Os LPS apresentaram partição preferencial para a fase concentrada em micelas, com altos valores de remoção, %REMLPS>98,0%. Ao contrário, a GFPuv foi recuperada preferencialmente na fase diluída, na qual existe maior volume disponível, resultando em valores de KGFPuv>1. A adição de sais ocasionou diminuição nos valores KGFPuv, provavelmente por causa da carga negativa que GFPuv adquiriu nas condições avaliadas. Os resultados do planejamento experimental mostraram que a melhor condição de partição obtida foi na região do ponto central, 4,0% (p/p) a 60,0°C, com KGFPuv>10. O processo por IMAC apresentou as maiores capacidades de adsorção de LPS-IDA-Ca+2 nas condições de menor pH e maior força iônica 4,0 e 1,0 mol/L, respectivamente. O processo de purificação por SMDFA empregado para a remoção de LPS contaminante presente em meio fermentado contendo GFPuv, demonstrou ser eficiente em recuperar a biomolécula-alvo na fase diluída e separar o principal contaminante na fase rica em micelas. Portanto, pode ser empregado como primeira etapa para a remoção de altas concentrações de LPS na purificação de proteínas hidrofílicas como a GFPuv. / The Aqueous Two-Phase Micellar System (ATPMS) was investigated for endotoxin (LPS) removal from preparations containing recombinant proteins of pharmaceutical interest, such as the green fluorescent protein (GFPuv). These systems usually consist of micellar surfactants solutions and offer both hydrophobic and hydrophilic environments, providing selectivity to the biomolecules partitioning according to its hydrophobicity. In this work, the implementation of the method for LPS quantification in contaminated samples was accomplished, as well as the obtaining of pure LPS and GFPuv from recombinant E. coli. Furthermore, the influence of Triton X-114 in the methodology for LPS quantification was studied, as the addition of MgSO4, CaCl2, KI, and (NH4)2SO4 into the partition of pure GFPuv and LPS in ATPMS. In addition, a statistical design (22) was carried out to evaluate the highest KGFPuv and %RECGFPuv. The E. coli cell lysate was tested under optimum conditions obtained with the statistical design. And, finally, the process by ionmetal affinity chromatography (IMAC) was used to investigate the adsorption of LPS in IDA-Ca2+ matrix. The results showed that the TX-114 caused high interference in the kinetic chromogenic method, according to the similarity of this molecule to LPS. The LPS showed preferential partitioning to the micellerich phase, with high values of removal, %REMLPS>98.0%. In the other hand, the GFPuv was preferentially recovered in the micelle-poor phase, in which there is greater volume available resulting in values of KGFPuv>1. The addition of salts caused a reduction in the values KGFPuv, probably because of the negative charge that the GFPuv acquired at the conditions evaluated. The results of the statistical design showed that the best partitioning condition obtained was in the central point region, 4.0% (wt/wt) at 60.0°C, with KGFPuv>10. The process by IMAC showed the highest adsorption of LPS-IDA-Ca+2 capacities at the conditions of lower pH and higher ionic strength 4.0 and 1.0 mol/L, respectively. The purification process for the LPS contaminant removal from E. coli fermentation containing GFPuv by ATPMS proved to be efficient in the recovering of target biomolecule in the micelle-poor phase, and separating the main contaminant in the micelle-rich phase. Furthermore, this system can be exploited as the first step for removal of higher LPS concentrations from hydrophilics protein purification.
157

Neurosteroid and somnogenic responses to endotoxin and hypoxia treatments in lambs

Billiards, Saraid Sheelagh January 2003 (has links)
Abstract not available
158

"The mode of action of Bacillus thuringiensis (Berliner) against the sheep louse, Bovicola ovis (Schrank)" / by Catherine Alexandra Hill.

Hill, Catherine Alexandra January 1998 (has links)
Bibliography: leaves 120-145. / vii, 145, [43] leaves, [23] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Reports Bt crystal protein toxicity to a phthirapteran species. Although Bt strain WB3516 may produce other unidentified toxins effective against B. ovis, the results provide strong evidence that the [delta]-endotoxin crystal proteins of strain WB3516 significantly contribute to the lousicidal toxicity of this strain. / Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 1998?
159

Studies of the pathogenesis of hemolytic uremic syndrome and thrombotic thrombocytopenic purpura

Karpman, Diana O. January 1997 (has links)
Thesis (doctoral)--Lund University, 1997. / Added t.p. with thesis statement inserted. Includes bibliographical references.
160

Efeito do ultrassom na eliminação de micro-oganismos e endotoxinas em dentes com infecção endodôntica primária / Ultrasound effect in eliminating microorganisms and endotoxins in teeth with primary endodontic infection

Flores Orozco, Esteban Isai [UNESP] 07 December 2016 (has links)
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No. of bitstreams: 1 floresorozco_ei_me_sjc.pdf: 3857078 bytes, checksum: 8192b396024e2af0be54f979f7662431 (MD5) Previous issue date: 2016-12-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os objetivos do presente estudo foram: a) Verificar a carga microbiana e quantificar endotoxinas presentes nos canais radiculares de dentes com infecção endodôntica primária; b) Comparar a efetividade antibacteriana e sobre endotoxinas do preparo biomecânico com dois métodos de irrigação final: com ou sem irrigação ultrassônica passiva; c) Correlacionar sinais e sintomas com a microbiota presente e complexos bacterianos; d) Relacionar níveis de endotoxinas e carga microbiana com sinais e sintomas clinicos. Foram selecionados para o estudo 20 dentes uniradiculares, que apresentavam infecção endodôntica primária e lesão periapical, sendo estes submetidos a TCFC. Os canais foram preparados com sistema reciprocante e irrigação com NaOCl 2.5%, seguido de dois protocolos de irrigação final: com e sem uso de ultrassom. Todos os canais foram preenchidos com MIC com hidróxido de cálcio + soro fisiológico e após 14 dias foram obturados com cones de guta-percha e cimento AH Plus. Foram realizadas coletas do conteúdo do canal, logo após a abertura coronária (1ª Coleta); após PBM (2ª Coleta) e após limpeza final dos canais com NaOCl seguido de EDTA por 5 min (grupo sem PUI); ou irrigação com NaOCl + PUI e EDTA + PUI (3ª Coleta) (grupo com PUI) . Foram avaliados sinais/sintomas clínicos previo ao tratamento.O conteúdo das coletas foi analisado a partir de sondas de DNA pelo método de hibridização DNA-DNA checkerboard e foi realizado teste de avaliação da atividade antimicrobiana por cultura microbiológica. Alem disso foi realizado quantificação de endotoxinas pelo Lisado de Amebócitos de Limulus (LAL). E a volumetria dos canais foi feita através da TCFC utilizando o software Nemotec®. Os resultados foram submetidos a análise estatístico pelos testes Mann Whitney e teste ANOVA a dois fatores de medidas repetidas (5%). Valor de p < 0.05 foi considerado estatisticamente significante. Houve associação entre dor à percussão e complexos laranja principal e laranja periférico. Fístula foi associada ao complexo laranja principal e laranja periférico. Foi observada redução de bactérias após o tratamento endodôntico. Ao utilizar o método de hibridização DNA-DNA checkerboard, as bactérias mais prevalentes foram S. constellatus, E faecalis, F. nucleatum, P. gingivalis, P. melaninogenica e S. intermedius na primeira coleta. Os métodos de irrigação diminuíram número de espécies bacterianas comparado à coleta inicial. A irrigação ultrassônica passiva apresentou diferença estatística significativa sobre bactérias anaeróbias. PUI não apresento diferença significativa sobre bactérias aeróbias nem endotoxinas comparado com irrigação convencional. Concluiu-se que todos os canais apresentaram micro-organismos sendo que anaeróbios estiveram presentes em grande quantidade. Após preparo biomecânico do canal radicular e irrigação com PUI, houve redução significante da carga de micro-organismos anaeróbios. Os micro-organismos mais resistentes ao preparo biomecânico com e sem PUI foram S. constellatus , E. faecalis, S. intermedius e L. bucalis. Houve associação positiva entre sinais e sintomas clínicos com complexo laranja e com micro-organismos. Os níveis de endotoxinas diminuíram após o preparo biomecânico não foram inferenciados por PUI a irrigação convencional. / The objective of this study were: a) to check the microbial load and to quantify endotoxin present in the root canals of teeth with primary endodontic infection; b) to compare the effectiveness of bacteria and endotoxin reduction of the biomechanical preparation with final irrigation methods: with or without passive ultrasonic irrigation (PUI); c) to correlate signs and symptoms with the present microbiota and bacterial complexes; d) to relate endotoxin and microbial load levels with signs and symptoms before biomechanical preparation. Twenty single-root teeth were selected for the study, presenting primary endodontic infections and periapical lesion, which underwent CBCT. The canals were prepared with reciprocating system and irrigation with 2.5% NaOCl, followed by two final irrigation protocols: with and without ultrasound. All canals were filled with MIC with calcium hydroxide + saline and after 14 days were filled with gutta percha and AH Plus. Samples from the content of canal were harvested, after coronal opening (1st Sample); after PBM (2nd Sample) and after final cleaning of the canals with NaOCl followed by EDTA for 5 min (group without PUI); or irrigation with NaOCl + PUI and EDTA + PUI (3rd Sample) (group with PUI). The contents of the samples were analyzed from DNA probes by the DNA-DNA checkerboard hybridization method and a test was performed to evaluate the antimicrobial activity by microbiological culture. In addition, quantification of endotoxins by Limulus Amebocyte Lysate (LAL) was performed. The canal volumetry was assessed through the CBCT using Nemotec® software. The results were submitted to statistical analysis by Mann Whitney and repeated measures two-way ANOVA (5%). Value of p <0.05 was considered statistically significant. There was an association between pain at percussion and main orange and peripheral orange complexes. Fistula was associated with the main orange and peripheral orange complex. A reduction of bacteria was observed after endodontic treatment. When using the DNA-DNA checkerboard hybridization method, the most prevalent bacterias were S. constellatus, E faecalis, F. nucleatum, P. gingivalis, P. melaninogenica and S. intermedius in the first collection. Irrigation methods decreased number of bacterial species compared to initial collection. The passive ultrasonic irrigation presents statistically significant difference on anaerobic bacteria. PUI did not present significant difference on aerobic bacteria or endotoxins compared to conventional irrigation. In conclusion, all canals had microorganisms, and anaerobes were present in large quantities. The most frequent microorganisms were S. constellatus, E. faecalis, F. nucleatum SP, P. gingivalis e S. intermedius. After biomechanical preparation of root canal and irrigation with PUI, there was a significant reduction of the anaerobic microorganism load. The microorganisms most resistant to biomechanical preparation with and without PUI were S. constellatus , E. faecalis, S. intermedius e L. bucalis. There was a positive association between clinical signs and symtoms with orange complex and with microorganisms. Endotoxin levels decreased after biomechanical preparation, while not influenced by PUI in comparison to conventional irrigation.

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