Helicobacter pylori infection and associated factors

Background and Objectives: Helicobacter pylori is linked to gastroduodenal pathologies. To determine the frequency and potential risk factors of the H. pylori infection. Material and methods: A cross-sectional study was conducted, including 227 patients, submitted to upper gastrointestinal endoscopy. A questionnaire was applied to the patients, before endoscopy. The biopsy specimens were obtained from the antrum and gastric body for histology and PCR. The chi-square test was used for the categorical data analysis. P-values0.05). However, we observed a significant association between the number of persons per household and presence of H. pylori (p=0.04). A statistically significant relation also was found between H. pylori and the patient’s age (p=0.04) and between the histological and endoscopic diagnoses and the H. pylori infection (p≤0.01). Conclusions: We found a significant relation between household crowding and presence of H. pylori, which seems facilitate the person-to-person transmission H. pylori within families. Our results also suggest a cohort phenomenon. The increase in the frequency of H. pylori infection according to age may be due the acquisition of bacterium predominantly in childhood, when the sanitary conditions were deficient, and not during adulthood. Once acquired and untreated, the persistent H. pylori infection might have led to the development of severe gastroduodenal diseases

Study effect of additive on PVDF membrane for CO2/N2 gas separation process

Flat sheet asymmetric membranes were produced from homogenous solution of Poly(vinylideneflouride) (PVDF) via phase inversion method using N-methyl-2-pyrrolidone (NMP) as the solvent and Lithium Chloride (LiCl) as an additive. The effect of addition of different ratio of LiCl in the casting solution on the membrane properties and performance were studied. The morphology and cross section of the produced membranes were observed by Scanning Electron Microscope (SEM). Then, the membranes were tested for chemical analysis to define the presence of LiCl in the membrane by using Fourier Transform Infrared (FTIR) spectroscopy. The permeation performances of the membranes were evaluated in terms of permeability and selectivity of the membranes in separating the gaseous mixture by using single gas permeation test. The addition of LiCl into the casting solution definitely improved the morphology and structure of the membrane. The macrovoid formation was suppressed and very fine pores were formed at higher LiCl content. Increasing the LiCl content significantly increased the selectivity of the PVDF membrane to separate the CO2/N2 gases but decreased the amount of the gases that passed through the membrane

cagE as a biomarker of the pathogenicity of Helicobacter pylori

Introduction Helicobacter pylori infection is associated with gastro-duodenal diseases. Genes related to pathogenicity have been described for H. pylori and some of them appear to be associated with more severe clinical outcomes of the infection. The present study investigates the role of cagE as a pathogenicity biomarker of H. pylori compare it to cagA, vacA, iceA and babA2 genes and correlate with endoscopic diagnoses. Methods Were collected biopsy samples of 144 dyspeptic patients at the Hospital of the Federal University of Rio Grande, Rio Grande do Sul, Brazil. After collection, the samples were sent for histological examination, DNA extraction and detection of all putative pathogenicity genes by PCR. Results Of the 144 patients undergoing endoscopy, 57 (39.6%) presented H. pylori by histological examination and PCR by detection of the ureA gene. Based on the endoscopic diagnoses, 45.6% (26/57) of the patients had erosive gastritis, while 54.4% (31/57) had enanthematous gastritis. The genes cagA, cagE, vacAs1/m1, vacAs1/m2 and iceA1 were related to erosive gastritis, while the genes vacAs2/m2, iceA2 and babA2 were associated to enanthematous gastritis. We found a statistically significant association between the presence of cagE and the endoscopic diagnosis. However, we detect no statistically significant association between the endoscopic diagnosis and the presence of cagA, vacA, iceA and babA2, although a biological association has been suggested. Conclusions Thus, cagE could be a risk biomarker for gastric lesions and may contribute to a better evaluation of the H. pylori pathogenic potential and to the prognosis of infection evolution in the gastric mucosa

Epigenetics in Forest Trees: State of the Art and Potential Implications for Breeding and Management in a Context of Climate Change

Forest trees are long-lived organisms subject to repeated environmental constraints throughout their long lifetimes. They have developed various mechanisms enabling them to cope with fluctuating environmental conditions during their life span, and to survive to current climate change. Epigenetics has recently emerged as a powerful set of mechanisms regulating various developmental processes, plant growth and responses to environmental variations. Such epigenetic mechanisms, which may remain stable along tree life or across generations, constitute a source of rapid phenotypic variations potentially improving adaptation of the plants in situations in which naturally occurring mutations are very rare. In this review, we summarize recent advances in forest tree epigenomics. We first draw the particularities of trees and the available (epi) genomics resources and strategies. Then, we discuss the potential contributions of epigenetics to cope with global climate change and regulate various developmental processes, such as developmental transitions during the annual cycle, phenotypic plasticity in response to environmental variations and stress memory, as well as local adaptation. Finally, we propose some challenges for forest management and highlighted the need to take epigenetics into account in forest tree breeding strategies