Tesis para optar al Título Profesional de Ingeniero Agrónomo. Tesis para optar al Grado de Magíster en Enología y Vitivinicultura / Los compuestos fenólicos provienen del metabolismo secundario de las plantas y se les ha asociado con propiedades antibacterianas. Entre las bacterias mas estudiadas por su alta prevalencia y efectos detrimentales sobre la salud humana se encuentran Escherichia coli y Helicobacter pylori, esta última asociada directamente con el cáncer gástrico. A pesar de lo anterior, existe limitada información acerca del efecto de la aplicación individual y en conjunto de polifenoles ampliamente distribuidos en los vegetales, sobre el crecimiento de E. coli y H. pylori. Así, la mayoría de los estudios han evaluado el efecto de los polifenoles contenidos en matrices de alta complejidad como bebidas y alimentos. Es por ello, que el objetivo de este estudio fue evaluar el efecto de la aplicación individual y en conjunto de kaempferol y (-)-epicatequina sobre H. pylori y E. coli en cultivos líquidos, sólidos y co-cultivos con células AGS. Para ello, se utilizaron pruebas de viabilidad de las bacterias en medio líquido, con el posterior recuento de UFC/mL; se realizaron pruebas de viabilidad en medio sólido, con la medición del halo de inhibición formado; se hicieron curvas de cinética de la inhibición de crecimiento en presencia de los compuestos y una evaluación del efecto de la (-)-epicatequina sobre la infección de H. pylori en células epiteliales (AGS). Los resultados demostraron que los compuestos (-)-epicatequina y kaempferol poseen actividad antibacteriana sobre las bacterias, siendo más efectiva, la (-)-epicatequina que el kaempferol. Además, se demostró que la bacteria H. pylori fue más sensible a ambos compuestos que E. coli. En los estudios de aplicación conjunta de los compuestos fenólicos, se observó que hubo un efecto sinérgico de kaempferol con (-)-epicatequina a bajas dosis, efecto que no fue observado a las concentraciones mayores probadas en los demás estudios. Finalmente, se observó que (-)-epicatequina posee una propiedad protectora sobre células AGS infectada con H. pylori.

The objectives of this dissertation are to (1) propose a conceptual framework describing the role of water in H. pylori transmission; (2) construct a database of water system and environmental characteristics using a geographic information system (GIS); (3) investigate the prevalence and incidence of H. pylori-related illnesses; and (4) examine the association between water system and environmental variables and H. pylori infection. The setting for this work was the Township of Langley, British Columbia. Based on findings from epidemiological and microbiological studies, a conceptual model of water’s role in H. pylori transmission was developed (Chapter 2). A population-based approach was employed in the construction of the GIS database to assign the risk factors outlined in the model to each Township resident (Chapter 3). Using administrative health services records for H. pylori-related illness, the average annual prevalence of gastric cancer, peptic ulcer disease and gastritis was 20, 450 and 1,777 cases per 100,000 population respectively, and average annual incidence was 13, 268 and 899 cases per 100,000 respectively. There was a significant decrease in the prevalence and incidence of peptic ulcer disease and the incidence of gastritis in the study population over the follow-up period, however, the costs to the health care system remained high (Chapter 4). In a nested case-control study, variables from the GIS database were linked to a database of serological results used to ascertain positive H. pylori infection. H. pylori infection was associated with mixed water source (adjusted OR = 0.63, versus groundwater only) and non-residential land use (adjusted OR=1.58, versus residential) among younger cases (Chapter 5). Odds ratios diminished in the older age groups, suggesting the presence of a cohort effect and that the exposures investigated were most relevant for younger individuals. The findings highlight possible transmission routes, relevant within the Canadian (and North American) context and evidence for public health interventions with regards to water supply and land use. Further, the methodology linked a variety of administrative data to cover all residents of the study area and assigned environmental variables over time, and can serve as a model for other environmental epidemiologic studies. / Medicine, Faculty of / Population and Public Health (SPPH), School of / Graduate

Urease of Helicobacter pylori is an important virulence factor implicated in the pathogenesis of many clinical conditions, such as chronic gastritis, peptic ulceration, and gastric cancer. Many urease inhibitors have been discovered, like phosphorodiamidates, hydroxamic acid derivatives, and imidazoles. Despite good activities at the enzyme level and excellent kinetic properties most of them have not been used as therapeutic agents in vivo because of their side effects, toxicity and instability. This has led to much attention to focus on exploring the novel urease inhibitory activities of natural products because of their low toxicity and good bioavailability. Honey, a natural product has been used in folk medicine due to its antitumor, antioxidant, antimicrobial and anti-inflammatory properties. The aims of this study were to isolate, characterise, purify urease produced by H. pylori and investigate the inhibitory effects of solvent honey extracts on its enzymatic activity. Urease was found to be both surface-associated and cytoplasmic. Maximum cytoplasmic urease activity was found to occur after 72 hr whereas maximum extracellular urease activities were found to occur after 96 hr. Characterization of the crude cytoplasmic urease revealed optimal activity at a pH of 7.5 and temperature of 40°C. The kinetic parameters Vmax and Km were 45.32 U ml-1 and 61.11 mM respectively.The honey extracts inhibited the activity of the crude urease in a concentration dependent manner. The Lineweaver-Burk plots indicated a non-competitive type of inhibition against H. pylori urease. The two honey extracts gave promising inhibitory activities against urease of H. pylori. Thus the results of this study delineates that inhibition of urease can ease development in therapeutic and preventative approaches based on the enzymatic activity of this Helicobacter protein.

Helicobacter pylori classified as a class 1 carcinogen is a common human pathogen implicated in certain gastrointestinal diseases. Helicobacter pylori infection is acquired mainly in childhood, especially in developing countries. H. pylori infection causes peptic ulcer, duodenitis, gastritis and cancer. The growing resistance of H. pylori to antibiotics used in its treatment as well as other innate limitations of the triple therapy has necessitated a search for alternative treatment from natural sources which could be readily available, less cost effective. The antimicrobial activity of solvents (acetone, ethanol, methanol, chloroform and water) crude extracts of Lippia javanica were investigated against 31 H. pylori strains by the agar well diffusion technique. The minimum inhibitory concentration (MIC) was determined by spectrophotometric analysis at 620 nm using the broth micro dilution method and the rate of kill by broth dilution method. Phytochemical analysis was also performed. H. pylori standard strain NCTC 11638 was included as a positive control. Metronidazole and amoxicillin were used as positive control antibiotics. The ANOVA test was used to analyze the results using SPSS version 17.0. The strains were inhibited by all the extracts with inhibition zones of diameter ranging from 0-36 mm and 0-35 mm for the control antibiotic, clarithromycin. The MIC90 ranged from 0.039- 0.625 mg/mL for acetone; 0.039-1.25mg/mL for methanol, 0.00195-0.313 mg/mL for ethanol; 0.01975-2.5 mg/mL for metronidazole and 0.0048-2.5 mg/mL for amoxicillin. Acetone extract completely inhibited strain PE369C at MIC (0.1 mg/mL) and 2× MIC (0.2 mg/mL) in 18h and at ½× MIC (0.05 mg/mL) in 36h. Strain PE466C was completely inhibited at 4× MIC in 72h. Phytochemical analysis revealed the presence of flavonoids, saponins, tannins, steroids and alkaloids. The results indicate that the extracts of the leaves of L. javanica may contain compounds with anti-H. pylori activity and merits further study to identify the compounds.

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2018-09-25T16:51:04Z No. of bitstreams: 1 texto completo.pdf: 950177 bytes, checksum: b83dd272b596a399531e767b4a5521e6 (MD5) / Made available in DSpace on 2018-09-25T16:51:04Z (GMT). No. of bitstreams: 1 texto completo.pdf: 950177 bytes, checksum: b83dd272b596a399531e767b4a5521e6 (MD5) Previous issue date: 2018-06-18 / A infecção gástrica pelo Helicobacter pylori afeta até 50% da população mundial e está fortemente associada à doença ulcerosa péptica e ao câncer gástrico. Já existe evidência de que a terapia de erradicação desse patógeno diminua a incidência dessas duas doenças. O segundo e o terceiro Consensos Brasileiros sobre H. pylori indicam a combinação de um inibidor de bomba de prótons (IBP) com amoxicilina e claritromicina como terapia de primeira escolha para o primeiro tratamento e a combinação de IBP com amoxicilina e levofloxacino como alternativa preferencial para o segundo tratamento, mas esses protocolos têm sido criticados pela diminuição recente de sua efetividade em vários pontos do globo. Como existem poucos dados sobre a efetividade dos esquemas de erradicação de H. pylori no Brasil, este estudo buscou por meio de análise de uma coorte retrospectiva composta de pacientes da zona da mata de Minas Gerais, descrever os tratamentos prescritos para erradicação de H. pylori com suas respectivas efetividades e suas correlações com características sociodemográficas. Foram analisados 5.010 prontuários, tendo sido encontrados 314 pacientes com informações completas sobre os tratamentos para erradicação de H. pylori, repartidos em dois períodos (2007 a 2011 e 2013 a 2016). Foram encontradas 264 prescrições de primeiros tratamentos para erradicação de H. pylori, com uso de IBP associado a amoxicilina e claritromicina por sete dias em 88,25% dos casos, com uma taxa de efetividade deste esquema de 54,07%. Não foram encontradas diferenças de efetividade conforme a escolha do IBP e entre os dois períodos analisados. Foram realizadas análises univariada e multivariada e por mineração de dados buscando correlacionar as variáveis idade, sexo, escolaridade, estado civil, naturalidade, local de residência e profissão com a efetividade dos primeiros e segundos tratamentos. Não foram encontradas associações consistentes entre a efetividade dos tratamentos e as variáveis mencionadas. Os dados apresentados demonstraram que, nessa coorte, as taxas de efetividade dos esquemas recomendados pelos Consensos Brasileiros sobre Helicobacter pylori foram inferiores às anteriormente descritas pela literatura brasileira. Mais estudos são necessários para aprimoramento dos esquemas terapêuticos empregados, considerando inclusive a emergência da resistência antimicrobiana do H. pylori. / Helicobacter pylori gastric infection affects almost 50% of the population worldwide. It is strongly associated to peptic ulcer disease and gastric cancer. There is evidence that H. pylori eradication reduces the incidence of both conditions. The second and third Brazilian Consensus on H. pylori indicate the combination of a proton pump inhibitor (PPI) with amoxicillin and clarithromycin as first line therapy for the first treatment and the combination of PPI with amoxicillin and levofloxacin as a preferred alternative for the second treatment. However, these protocols have been criticized recently because a decrease in their effectiveness has been observed worldwide. As we have little data on the H. pylori eradication therapy effectiveness in Brazil, this study has analyzed retrospectively a cohort composed by patients living in southeast Minas Gerais State, southeast Brazil, to describe the rate of H. pylori eradication and its correlation to sociodemographic characteristics. Five thousand and ten medical records were analyzed and 314 patients with complete information on H. pylori eradication therapy, from two periods (2007 to 2011 and 2013 to 2016), were included. Two hundred sixty-four prescriptions were found for first attempt to eradicate H. pylori with an effectivity rate of 54.07% for the scheme using PPIs associated with amoxicillin and clarithromycin for seven days. No statistical differences were observed about treatment effectiveness according to the choice of IBP and between the two analyzed periods. Univariate, multivariate and data mining analyses correlating age, gender, schooling, marital status, naturality, place of residence and profession with the effectiveness of the first and second treatments were performed. No correlations among these features were found. In this cohort, H. pylori eradication rate using the protocols recommended by the Brazilian consensus on Helicobacter pylori were inferior to those previously described by Brazilian literature. More studies are needed to find the best protocols, considering the emerging H. pylori drug resistance.

京都大学 / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第22384号 / 社医博第106号 / 新制||社||医11(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 妹尾 浩, 教授 古川 壽亮, 教授 中川 一路 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM

The aim ofthis study was to reveal the presence ofHelicobacter pylori (HP) in the Waldeyers lymphatic tissue in the group ofchildren and adults, along with its possible role in the etiology of tonsillar carcinoma and benign diseases (chronic tonsillitis, OSAS, adenoids). In our study we have confirmed the hypothesis that HP is presented m the Waldeyers lymphatic tissue. as well as in the stomach and that the oropharynx and epipharynx are the an extragastric reservoir ofHP. Mucosa associated lymphatic tissue in the stomach is similar to lymphatic tissue ofWaldeyer ring. These conditions can be very favourable for the survival ofHP and thus can promote inflammation changes and immune changes as well as in the stomach. ln our study, using the real-time PCR method we have detected high incidence ofHP DNA in adenoids and tonsillar tissue. ln the group ofbenign diseases, the most frequent genotypes were CagA­ VacAsIbm1 and CagA-VacAslbm2. In the group of patients with tonsillar carcinoma, the most frequent genotype was CagA-VacAslbml. Genotyping identified strains ofHP showed differences in comparison with the predominant strains which are most frequently found in the stomach. Genotypic analysis ofI-IP strains showed that the less prevalent virulent strains ofHP, known as cagA negative and vacA positive....

Molecular typing of strains among the highly diverse population of Helicobacter pylori (H. pylori) is an important approach for both basic and clinical studies. Genomic DNAs prepared from 18 gastric biopsy specimens, 21 H. pylori clinical isolates obtained from gastric biopsy specimens, and five isolates collected from a single patient at weekly intervals, were subjected to a combined single- and double-stranded conformational polymorphism (SDSCP) assay. The results showed that 19 of 21 isolates tested were discriminated by SDSCP analysis. SDSCP analysis of five H. pylori isolates collected from the same patient at different times resulted in five identical profiles, suggesting the reproducibility of the method. When DNA preparations from 18 gastric biopsy specimens were subjected to SDSCP analysis, 18 unique profiles were generated that matched those of their corresponding cultured H. pylori isolates from each patient. For comparison, polymerase chain reaction (PCR)-based restriction fragment length polymorphism analysis yielded only nine profiles for 20 strains. The data suggest that SDSCP analysis may be an effective and reliable method for differentiation of H. pylori strains directly from gastric biopsy specimens without requiring isolation of the organisms by culture.

We have previously reported a high prevalence of H. pylori DNA in saliva. In this study, the cytotoxin genotypes of H. pylori strains from both stomach and saliva were compared in 31 patients with gastritis and peptic ulcer. The cagA, vacA m1, vacA m2, and vacA s1 genotypes were analyzed by PCR. The 417 bp PCR products from three patients were also subjected to DNA sequencing analysis. There was 95% agreement between stomach H. pylori isolates and their corresponding saliva DNA in at least one cytotoxin genotype; 86% agreement with two cytotoxin genotypes; 59% agreement with three cytotoxin genotypes; and 27% agreement with all four cytotoxin genotypes studied. DNA sequencing from three patients showed 78.0%, 64.0%, and 66.9% homology of H. pylori from both sources, respectively. The data suggest that more than one H. pylori strain may exist in the stomach and saliva in the same patient.

Background: The prevalence of H. pylori is greater than 50% in low development countries. In children, infection with H. pylori produces effects such as low height, impairment in growth especially in pubertal age. Polymerase Chain Reaction has a high sensitivity and specificity of 89.6% and 100% respectively, compared to other invasive methods. The objective of this study is to determine the frequency of patients with presence of H. pylori in asymptomatic children in a rural community in the north of Peru, using PCR technique in stool samples. Methods: A cross-sectional study with a convenience sampling was performed, resulting in 147 children aged between 6-14 years old of the district of San Pablo in Cajamarca, Peru. Using stool samples H. pylori DNA was obtained, then PCR amplification was done, and sequencing those with positive results, in an agreement with Macrogen, Seoul - Korea. Results: It was found a frequency of H. pylori positive cases of 21.1% with a CI 95% of 14.8 to 28.6. It was found a frequency (p=0.01) of positive for H. pylori among males (29% IC95: 19.1- 40.5) compared to women (12.7%; IC95: 6.0-22.7). There was no statistically significant differences between those positive and negative patients with H. pylori compared to age (p = 0.57), presence of overweight (p = 0.09), or excreta disposal (p = 0.71). It was not found significance difference among other variables. Conclusion: Our study found a high frequency of H. pylori determined by a molecular test with high sensitivity and specificity, demonstrating the feasibility of its implementation in rural communities. It can be considered as a tool for surveillance in areas of high prevalence of H. pylori infection. / Tesis