22 resultados para Helicobacter pylori Teses
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
There is substantial evidence that infection with Helicobacter pylori plays a role in the development of gastric cancer and that it is rarely found in gastric biopsy of atrophic gastritis and gastric cancer. On advanced gastric tumors, the bacteria can be lost from the stomach. Aims - To analyze the hypothesis that the prevalence of H.pylori in operated advanced gastric carcinomas and adjacent non-tumor tissues is high, comparing intestinal and diffuse tumors according to Laurens classifi cation. Methods - A prospective controlled study enrolled 56 patients from Hospital Universitrio, Federal University of Rio Grande do Norte, Natal, RN, Brazil, with advanced gastric cancer, treated from February 2000 to March 2003. Immediately after partial gastrectomy, the resected stomach was opened and several mucosal biopsy samples were taken from the gastric tumor and from the adjacent mucosa within 4 cm distance from the tumor margin. Tissue sections were stained with hematoxylin and eosin. Laurens classifi cation for gastric cancer was used, to analyse the prevalence of H. pylori in intestinal or diffuse carcinomas assessed by the urease rapid test, IgG by ELISA and Giemsa staining. H. pylori infected patients were treated with omeprazole, clarithromycin and amoxicillin for 7 days. Follow-up endoscopy and serology were performed 6 months after treatment to determine successful eradication of H. pylori in non-tumor tissue. Thereafter, follow-up endoscopies were scheduled annually. Chi-square and MacNemar tests with 0.05 signifi cance were used. Results - Thirty-four tumors (60.7%) were intestinal-type and 22 (39.3%) diffuse type carcinomas. In adjacent non-tumor gastric mucosa, chronic gastritis were found in 53 cases (94.6%) and atrophic mucosa in 36 patients (64.3%). All the patients with atrophic mucosa were H. pylori positive. When examined by Giemsa and urease test, H. pylori positive rate in tumor tissue of intestinal type carcinomas was higher than that in diffuse carcinomas. In tumor tissues, 34 (60.7%) H. pylori-positive in gastric carcinomas were detected by Giemsa method. H. pylori was observed in 30 of 56 cases (53.5%) in tissues 4 cm adjacent to tumors. This difference was not signifi cant. Eradication of H. pylori in non-tumor tissue of gastric remnant led to a complete negativity on the 12th postoperative month. Conclusions - The data confi rmed the hypothesis of a high prevalence of H. pylori in tumor tissue of gastric advanced carcinomas and in adjacent non-tumor mucosa of operated stomachs. The presence of H. pylori was predominant in the intestinal-type carcinoma
Resumo:
The expression of human leukocyte antigen G (HLA-G) and human leukocyte antigen E (HLA-E) in physiological and pathological processes remains unknown, it is believed that these molecules play a fundamental role in the establishment and maintenance of immune tolerance by inhibiting the functions of immunocompetent cells. In literature we found no published study involving the bacterium Helicobacter pylori (H. pylori) with expression of HLA-G and HLA-E. The objective this study is investigated the expression of this protein in gastric biopsies of patients with the bacterium H. pylori. Sixty-four biopsies of the patients with diagnosis of infection by H. pylori were evaluated to expression of HLA-G and HLA-E. The samples were stratified according to the presence of carcinoma or peptic ulcers. Patients without H. pylori were used to control. To investigate the expression of this protein were used immunohistochemistry technique with monoclonal antibody anti-HLA-G and anti-HLA-E. Other criteria such as analysis of the inflammatory infiltrate (hematoxylin-eosin) and identification of H. pylori (Giemsa) were analyzed. We detected HLA-G and HLA-E molecules in the most samples containing ulcer and gastric carcinoma. In negative control group was not detected the presence of HLA-G and HLA-E. The presence of H. pylori seems modulate the expression of HLA-G and HLA-E, favoring the evolution of infection, giving different degrees of gastric lesion in epithelium of these patients
Resumo:
Helicobacter pylori is the main cause of gastritis, gastroduodenal ulcer disease and gastric cancer. The most recommended treatment for eradication of this bacteria often leads to side effects and patient poor compliance, which induce treatment failure. Magnetic drug targeting is a very efficient method that overcomes these drawbacks through association of the drug with a magnetic compound. Such approach may allow such systems to be placed slowed down to a specific target area by an external magnetic field. This work reports a study of the synthesis and characterization of polymeric magnetic particles loaded with the currently used antimicrobial agents for the treatment of Helicobacter pylori infections, aiming the production of magnetic drug delivery system by oral route. Optical microscopy, scanning electron microscopy, transmission electron microscopy, x-ray powder diffraction, nitrogen adsorption/desorption isotherms and vibrating sample magnetometry revealed that the magnetite particles, produced by the co-precipitation method, consisted of a large number of aggregated nanometer-size crystallites (about 6 nm), creating superparamagnetic micrometer with high magnetic susceptibility particles with an average diameter of 6.8 0.2 μm. Also, the polymeric magnetic particles produced by spray drying had a core-shell structure based on magnetite microparticles, amoxicillin and clarithromycin and coated with Eudragit S100. The system presented an average diameter of 14.2 0.2 μm. The amount of magnetite present in the system may be tailored by suitably controlling the suspension used to feed the spray dryer. In the present work it was 2.9% (w/w). The magnetic system produced may prove to be very promising for eradication of Helicobacter pylori infections
Resumo:
Helicobacter pylori is a spiral, Gram negative, mobile, and microaerophilic bacteria recognized as a major cause of gastritis, ulcer, gastric cancer, and gastric low grade, B cell, mucosa associated lymphoid tissue (MALT) lymphoma, constituting an important microorganism in medical microbiology. Its importance comes from the difficulty of treatment because the requirement of multiple drugs use, besides the increasing emergence of resistant and multiresistant strains to antibiotics used in th e clinic. In order to expand safe and effective therapeutic options , chemical studies on medicinal plants by obtaining extracts, fractions, isolated compounds or essential oils with some biological activity has been intensified . Given the above, the objective was to evaluate the inhi bitory activity of organic extracts derived from Syzygium cumini and Encholirium spectabile, with antiulcer history, and the essential oil, obtained from S. cumini, against H. pylori (ATCC 43504) by the disk diffusion method, for qualitative evaluation, an d determination of minimum inhibitory concentration (MIC) using the broth microdilution method, for quantitative analysis. Also was evaluated the extracts in vitro toxicity by a hemolytic assay using sheep red blood cells, and VERO and HeLa cells using the MTT assay to analyze cell viability. The extracts of both plant used in antimicrobial assays did not inhibit bacterial growth, however the essential oil of S. cumini (SCFO) proved effective, showing MIC value of 205 g/mL (0.024 % dilution of the original oil). In the hemolytic assay, the same oil shows moderate toxicity, by promote 25% hemolysis at 1000 g/mL. Regarding the cytotoxicity in cell culture, the SCFO, at 260 g/mL, affected the cell viability around 80% of HeLa and 50% of VERO cells. So the oi l obtained from S. cumini leaves has antimicrobial activity against H. pylori and cytotoxicity potential, suggesting a source of new molecule drug candidates, since new stages of toxicity in vitro and in vivo, as well, chemical characterization be evaluate d. Moreover, the development of a prospective drug delivery system can result in a prototype to be used in preclinical tests.
Resumo:
There is substantial evidence that infection with Helicobacter pylori plays a role in the development of gastric cancer and that it is rarely found in gastric biopsy of atrophic gastritis and gastric cancer. On advanced gastric tumors, the bacteria can be lost from the stomach. Aims - To analyze the hypothesis that the prevalence of H.pylori in operated advanced gastric carcinomas and adjacent non-tumor tissues is high, comparing intestinal and diffuse tumors according to Laurens classifi cation. Methods - A prospective controlled study enrolled 56 patients from Hospital Universitrio, Federal University of Rio Grande do Norte, Natal, RN, Brazil, with advanced gastric cancer, treated from February 2000 to March 2003. Immediately after partial gastrectomy, the resected stomach was opened and several mucosal biopsy samples were taken from the gastric tumor and from the adjacent mucosa within 4 cm distance from the tumor margin. Tissue sections were stained with hematoxylin and eosin. Laurens classifi cation for gastric cancer was used, to analyse the prevalence of H. pylori in intestinal or diffuse carcinomas assessed by the urease rapid test, IgG by ELISA and Giemsa staining. H. pylori infected patients were treated with omeprazole, clarithromycin and amoxicillin for 7 days. Follow-up endoscopy and serology were performed 6 months after treatment to determine successful eradication of H. pylori in non-tumor tissue. Thereafter, follow-up endoscopies were scheduled annually. Chi-square and MacNemar tests with 0.05 signifi cance were used. Results - Thirty-four tumors (60.7%) were intestinal-type and 22 (39.3%) diffuse type carcinomas. In adjacent non-tumor gastric mucosa, chronic gastritis were found in 53 cases (94.6%) and atrophic mucosa in 36 patients (64.3%). All the patients with atrophic mucosa were H. pylori positive. When examined by Giemsa and urease test, H. pylori positive rate in tumor tissue of intestinal type carcinomas was higher than that in diffuse carcinomas. In tumor tissues, 34 (60.7%) H. pylori-positive in gastric carcinomas were detected by Giemsa method. H. pylori was observed in 30 of 56 cases (53.5%) in tissues 4 cm adjacent to tumors. This difference was not signifi cant. Eradication of H. pylori in non-tumor tissue of gastric remnant led to a complete negativity on the 12th postoperative month. Conclusions - The data confi rmed the hypothesis of a high prevalence of H. pylori in tumor tissue of gastric advanced carcinomas and in adjacent non-tumor mucosa of operated stomachs. The presence of H. pylori was predominant in the intestinal-type carcinoma
Resumo:
Magnetic targeting is being investigated as a means of local delivery of drugs, combining precision, minimal surgical intervention, and satisfactory concentration of the drug in the target region. In view of these advantages, it is a promising strategy for improving the pharmacological response. Magnetic particles are attracted by a magnetic field gradient, and drugs bound to them can be driven to their site of action by means of the selective application of magnetic field on the desired area. Helicobacter pylori is the commonest chronic bacterial infection. The treatment of choice has commonly been based upon a triple therapy combining two antibiotics and an anti-secretory agent. Furthermore, an extended-release profile is of utmost importance for these formulations. The aim of this work was to develop a magnetic system containing the antibiotic amoxicillin for oral magnetic drug targeting. First, magnetic particles were produced by coprecipitation of iron salts in alkaline medium. The second step was coating the particles and amoxicillin with Eudragit S-100 by spray-drying technique. The system obtained demonstrated through the characterization studies carried out a possible oral drug delivery system, consisting in magnetite microparticles and amoxicillin, coated with a polymer acid resistant. This system can be used to deliver drugs to the stomach for treatment of infections in this organ. Another important finding in this work is that it opens new prospects to coat magnetic microparticles by the technique of spray-drying.
Resumo:
The infection caused by Helicobacter pylori (H. pylori) is associated with gastroduodenal inflammation can lead to the development of gastritis, gastric or duodenal ulcer and gastric cancer (type 1 carcinogen for stomach cancer). Amoxicillin is used as first-line therapy in the treatment of H. pylori associated to metronidazole or clarithromycin, and a proton pump inhibitor. However, the scheme is not fully effective due to inadequate accumulation of antibiotics in gastric tissue, inadequate efficacy of ecological niche of H. pylori, and other factors. In this context, this study aimed to obtaining and characterization of particulate systems gastrorretentivos chitosan - amoxicillin aiming its use for treatment of H. pylori infections. The particles were obtained by the coacervation method / precipitation using sodium sulfate as precipitating agent and crosslinking and two techniques: addition of amoxicillin during preparation in a single step and the sorption particles prior to amoxycillin prepared by coacervation / precipitation and spray drying. The physicochemical characterization of the particles was performed by SEM, FTIR, DSC, TG and XRD. The in vitro release profile of amoxycillin free and incorporated in the particles was obtained in 0.1 N HCl (pH = 1.2). The particles have higher encapsulation efficiency to 80% spherical shape with interconnected particles or adhered to each other, the nanometric diameter to the systems obtained by coacervation / precipitation and fine for the particles obtained by spray drying. The characterization by FTIR, DSC and XRD showed that the drug was incorporated into the nanoparticles dispersed in the polymeric matrix. Thermal analysis (TG and DSC) indicated that encapsulation provides greater heat stability to the drug. Amoxicillin encapsulated in nanoparticles had slower release compared to free drug. The particles showed release profile with a faster initial stage (burst effect) reaching a maximum at 30 minutes 35% of amoxicillin for the system in 1: 1 ratio relative to the polymer and 80% for the system in the ratio 2: 1. Although simple and provide high encapsulation efficiency of amoxicillin, the process of coacervation, precipitation in one step using sodium sulfate as precipitant / cross-linker must be optimized in order to adjust the release kinetics according to the intended application.
Resumo:
VITULLO, Nadia Aurora Vanti. Avaliao do banco de dissertaes e teses da Associao Brasileira de Antropologia: uma anlise cienciomtrica. 2001. 143 f. Dissertaao (Mestrado) - Curso de Mestrado em Biblioteconomia e Cincia da Informao, Pontifcia Universidade Catlica de Campinas, Campinas, 2001.
Resumo:
OLIVEIRA, Raimundo Muniz de. Biblioteca digital de teses e dissertaoes: uma referencia fundamental. In: CINFORM ENCONTRO NACIONAL DE ENSINO E PESQUISA DA INFORMAAO,HUMANISMO E DESENVOLVIMENTO CIENTIFICO E TECNOLOGICO,7.,2007,Salvador. Anais...Salvador:UFBA, 2007.Disponivel em:www.cinform.ufba.br>. Acesso em: 27 set. 2007. Acesso em: 27 set. 2010.
Resumo:
CUNHA, Jacqueline de Arajo. Biblioteca Digital de Teses e Dissertaes: uma estratgia de preservao da memria cientfica. 2009. 141f. Dissertao (Mestrado)- Programa de Ps-Graduao em Cincia da Informao. Universidade Federal da Paraba, Joo Pessoa, 2009.
Resumo:
A pesquisa aborda o uso das Tecnologias de Informao e Comunicao, que vem revolucionando as atividades e ocasionando muitas mudanas relacionadas ao acesso e uso de informaes. O objetivo foi analisar o grau de utilizao do conhecimento cientfico produzido pelos Programas de Ps-Graduao das Universidades Pblicas Brasileiras, atravs da BDTD, pelos mestrandos dos referidos programas. Nos procedimentos metodolgicos realizados, procurou-se inicialmente analisar o amplo espectro da populao do corpus da pesquisa. Em razo da impossibilidade de trabalhar com os Programas de Ps-Graduao como um todo, optou-se por fazer um recorte, elegendo os cursos de Ps-Graduao em Cincia da Informao, vez que estes representam o principal segmento social de interesse da pesquisa. Foi utilizado o mtodo de estudo de usurios, onde se optou por adotar o grupo, estudos orientados aos usurios, que identifica as necessidades e comportamento de acesso e uso da informao. Para coletar os dados, elaborou-se um questionrio semi-estruturado com 25 questes, que versavam sobre o uso, dificuldades de acesso e recuperao da informao, bem como a satisfao na utilizao dessa fonte informacional. Dentre os vrios resultados obtidos, podemos destacar o fato de que a maioria dos mestrandos (71,8%) s teve contato com a BDTD somente no momento em que se encontrava cursando o mestrado e, somente 24,3%, tiveram contato durante a graduao. Estes resultados representam um problema, que pode afetar o bom desempenho do projeto BDTD, o qual consiste em disseminar e divulgar a produo cientfica dos Programas de Ps-Graduao das Universidades Pblicas Brasileiras para a sua comunidade. Foi observado tambm, que os mestrandos oriundos do curso de Biblioteconomia tende a ter contato com a BDTD bem mais cedo do que mestrandos de outros cursos de graduao. A fim de minimizar o problema detectado, prope-se uma divulgao mais eficaz na graduao atravs de dois procedimentos: Primeiro, o docente deve fazer uma divulgao mais eficaz da BDTD junto aos discentes de todos os cursos de graduao; segundo: dever ser feita a divulgao na mdia eletrnica, atravs da insero de cones da BDTD, nos portais dos Departamentos dos Cursos de Graduao das Universidades Pblicas Brasileiras. Acredita-se que com estes procedimentos seja possvel aperfeioar o uso dessa fonte de informao cientfica.
Bibliotecas digitais de teses e dissertaes brasileiras: paradigma do acesso livre informao cientfica
Resumo:
A evoluo da comunicao cientfica ao longo do tempo e o impacto causado pela A evoluo da comunicao cientfica ao longo do tempo e o impacto causado pela A evoluo da comunicao cientfica ao longo do tempo e o impacto causado pela se analisar as contribuies da Biblioteca Digital de Teses e Dissertaes (BDTD)para a comunicao cientfica atual, destacando possibilidades emergentes e desafios a serem superados. Apresenta uma breve evoluo da comunicao cientfica ao longo do tempo; discute os impactos causados pela Internet na comunicao, disponibilizao e acessibilidade de informaes tcnico-cientficas; e caracteriza BDTD destacando os desafios a serem superados. Dentre eles esto, a questo dos direitos autorais que ocasionam a baixa adeso dos autores ao projeto piloto do IBICT para disponibilizar teses e dissertaes no meio eletrnico. Para este desafio, so apontadas sugestes.
Resumo:
As bibliotecas de teses e dissertaes tm um papel fundamental para o desenvolvimento cientfico e cultural de um pas. Nesse sentido, buscou-se, de modo geral, analisar o panorama brasileiro das bibliotecas digitais de teses e dissertaes. Especificamente, objetivou-se caracterizar a sociedade da informao enquanto contexto das BDTD; caracterizar os vrios tipos de bibliotecas surgidos a partir da insero das novas tecnologias de informao e comunicao; identificar as diretrizes norteadoras da implantao de BDTD; e levantar as BDTD existentes no Brasil. Para tato, alm de levantamento bibliogrfico, realizou-se uma pesquisa nos sites de instituies de ensino superior brasileiras que j dispe de bibliotecas digitais de teses e dissertaes em funcionamento. A anlise e interpretao destes dados nos permite considerar que no Brasil as BDTD encontram-se num estgio embrionrio, sendo relevante pesquisar a histrica implantao e configurao desse novo modelo de biblioteca.
Resumo:
This work has the main purpose of conducting a survey of educational products present in dissertations and doctoral theses focused on the use of history in mathematics teaching and Didactics of mathematics with a French foundation produced in graduate programs in the strict sense of the Brazil between 1990 and 2010, the areas of Education, Mathematics Education, school of Natural Sciences and Mathematics and related areas, according to the research proposal of Mendes (2010). Our interest was to select the products that present concrete proposals for educational activities that can be used in the classroom of Basic Education and Training of Teachers of Mathematics. The research was implemented through a bibliographic study documents the Bank of dissertations and theses from CAPES, libraries and archives of some Postgraduate programs in the country who focus their studies on the subject object of this research, besides the Brazilian Digital Library Theses and Dissertations (BDBTD). From this survey we selected works that present educational products materialized in blocks of activities based on the use of teaching history of mathematics to the classroom as well as the sequence of activities based on the Teaching of Mathematics. In possession of material, produce a CD-ROM containing the selected activities, in order to help support the work of teachers regarding the use of these activities, as a supplementary material to textbooks in their math classes
Resumo:
This research aims to make a reflective analysis about the academic production originated in the stricto sensu post graduation programs in the country, produced in the period of 1990 to 2010, in the field of History of Mathematics, especifically on works about the History of Mathematics in Mathematics education and that present pedagogical proposals that make use of the History of Mathematics in order to teach Mathematics. Defending the thesis that the researches on mathematics education with goals turned to the use of didactic proposals related to the history of mathematic that take in consideration the coherency between epistemological aspects inherent to mathematics history and anthological elements materialized on the conceptions of mathematics and mathematics history and of apprenticeship (implicitly or explicitly exposed) may originate significant contribution to the field of history of mathematics on education. Among these, nine were Masters Degree dissertations and five PHDs theses. The reflective analysis was accomplished from two matrixes; one from theoretical nature and the other, ontologic nature, elaborated from the pretexts of Sanches Gamboa, about the epistemological analysis from academic production in the field of Mathematics Education and the following theoretical perspectives in the field of History of Mathematics Education, that are: linear evolutionary theory, structural construtivist operative, evolutionary discontinuous, historical and socialcultural investigation and the use of activities estimulating the usage of verbal and nonverbal expressions. These perspectives were based on the works of Miguel and Miorim, Mendes and Radford. As results, we have detected some established dissonances between the categories related to theoretical and ontologic levels and the pedagogical proposal presented in these researches. On the other hand, we have discovered works that are able to establish consonances between the theoretical and ontological elements and the presented pedagogical proposal. These works carry significative contributions to the field of History of Mathematics applied to Mathematics pedagogical practice, inclusively presenting significative theoretical elements to the production of knowledge recognized as scientific in the Mathematics field
