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The effect of high temperature stress (27°C or 37°C for 24 h) on total gene expression profiles in the annual-fruiting raspberry (Rubus idaeus L.) cultivars 'Autumn Bliss', 'Autumn Treasure', 'Erika', and 'Polka' were evaluated at the floral initiation stage using a customised Rubus microarray. Significantly affected genes were obtained by pairwise t-tests using 'volcano plots' for each cultivar x treatment. A 10°C elevation in temperature altered levels of expression, in at least one cultivar, of 644 differentially expressed genes in total, with 'Erika' and 'Autumn Treasure' showing elevated expression of 38 genes compared to 'Autumn Bliss' and 'Polka'. We identified 12 common candidate genes that were modulated differentially in 'Autumn Bliss' and 'Erika' at 37°C compared to 27°C. In addition, two aquaporin genes (PIP1 and TIP2) were down-regulated in 'Autumn Bliss', but up-regulated in 'Autumn Treasure', 'Polka', and 'Erika' at 37°C. Other down-regulated genes from the list of 38 genes included those encoding major latex-like proteins, plasma membrane proteins, cysteine rich proteins, and other stress-related proteins. Validation by real-time quantitative RT-PCR (RT-qPCR) indicated subtle changes in differential gene expression, suggesting a mild response to heat stress. This study used molecular tools to increase our understanding of, and to identify candidate genes involved in, the heat stress response of four annual-fruiting raspberry cultivars. [ABSTRACT FROM AUTHOR]

Background: Peptic ulcer epidemiology has changed considerably within the past century. The aim of this study was to assess the 11-year cumulative incidence of peptic ulcer disease and examine the relationship between ulcer incidence and psychosocial and genetic factors. Methods: A random sample of 2416 Danish adults with no history of peptic ulcer disease residing in Copenhagen County, Denmark, attended a population-based prospective cohort study in 1983 and 1994. All participants reported whether they had had an ulcer diagnosed within the observation period. Information on socio-economic factors, family history of peptic ulcer disease (PUD) and lifestyle practices was obtained from a questionnaire. Lewis blood group antigens were assessed from blood samples and Helicobacter pylori infection status was determined with an in-house IgG ELISA. Results: The overall 11-year cumulative incidence proportion of PUD was 2.9% (95% CI (2.2; 3.6)), i.e. 1.6% (95% CI (1.1; 2.1)) for duodenal ulcer, and 1.3% (95% CI (0.8; 1.7)) for gastric ulcer. Poor socio-economic status increased the risk of PUD independently of H. pylori infection (odds ratio 2.7, 95% CI (1.1; 6.1)) and accounted for 17% of all ulcer cases. High physical activity at work increased the risk of PUD in people infected with H. pylori (odds ratio 2.6, 95% CI (0.8; 8.0)). Family history of PUD or Lewis blood group antigens did not relate to ulcer incidence. Conclusions: Poor socio-economic status is an important risk factor for PUD that exerts its effect independently of H. pylori infection. Strenuous work may increase the risk of PUD in people with H. pylori infection. Genetic factors do not influence the risk of PUD in Danish adults. [ABSTRACT FROM AUTHOR]

Background: Infection with Helicobacter pyloriin childhood may be the initiation of a lifelong coexistence between microorganisms and epithelial cells resulting in chronic inflammation. The adhesion pattern of H. pylori found in antral biopsies from a group of H. pylori-infected children with recurrent abdominal pain was compared with a group of H. pylori-infected adults suffering from dyspepsia, in an attempt to reveal differences in the type of adhesion. Methods: The histology of antrum biopsies and the ultrastructure of adherent H. pylori in biopsies from 26 children (median age, 10.1 years) were compared with organisms in biopsies from 19 adults (median age, 54.4 years). Results: More than 1000 adherent H. pylori were studied and divided into four types of adhesion: 1) contact to microvilli; 2) connection to the plasma membrane via filamentous material; 3) adhesive pedestal formation; and 4) abutting or making a depression in the plasma membrane. Contact to microvilli was significantly higher (69% versus 39%; P = 0.002) in children compared with adults and comprised two-thirds of all adherent organisms in children. The more intimate adhesion types as abutting or adhesive pedestals dominated in adults. Conclusions: These results indicate a change in contact types between H. pylori and gastric epithelial cells in adults compared with children and this may be a natural development in the lifelong infection of humans. [ABSTRACT FROM AUTHOR]

Discusses the possible clinical importance of the transformation of Helicobacter pylori (H. pylori) into coccoid forms. Role of the coccoid forms in the survival of the bacterium outside the human body; Treatment of H. pylori infections; Morphology of spiral and coccoid forms; Viability of coccoid forms; Pathologic changes caused by spiral and coccoid forms; Pathogenic properties; Induction in vitro.

Background: Helicobacter pylori plays an important role in peptic ulcer disease, although not all H. pylori-infected persons will develop a peptic ulcer. Currently, H. pylori strains cannot be divided into commensals and pathogens. Methods: Fifty H. pylori strains were cultured from patients divided into five groups on the basis of upper endoscopic findings: gastric ulcer, duodenal ulcer, gastritis, esophagitis, or normal. The ultrastructural adherence pattern in vivo, autoagglutination, hemagglutination, adhesion to human gastric adenocarcinoma (AGS) cells, and the lipopolysaccharide (LPS) profile of H. pylori strains were recorded; randomly amplified polymorphic DNA (RAPD) and urease gene typing were performed and correlated with diagnostic groups. Results: Electron micrographs showed that H. pylori strains from patients with gastric ulcers adhered more frequently through filamentous strands and were less frequently found free in mucus than any other diagnostic group (P < 0.0001). Neither median hemagglutination titer nor median adhesion capacity to a human gastric adenocarcinoma cell line was related to endoscopic findings. Nevertheless, H. pylori strains from patients with gastric ulcers were more prone to autoagglutinate than were strains from the other diagnostic groups (P = 0.03). H. pylori strains from gastric ulcer patients were found to be more homogeneous, as determined by RAPD and urease gene typing, than strains from the other diagnostic groups (P < 0.01). In addition, a positive correlation was found between a patient's age and the adhesion to AGS cells of the patient's H. pylori strain (P = 0.006). Conclusion: A combination of an H. pylori autoagglutination test, RAPD, and urease gene typing may be useful in separating gastric ulcer-related strains from duodenal ulcer-related and non-ulcer dyspepsia-related strains. [ABSTRACT FROM AUTHOR]

Background: It has been debated which diagnostic test should be preferred for the diagnosis of Helicobacter pylori in patients with gastroduodenal diseases. Methods: The H. pylori infection was diagnosed prospectively in 97 untreated patients. H. pylori was diagnosis by means of tests based on five different principles: 1) culture, 2) microscopy (HLO), 3) urease activity (urea breath test (UBT) and urease test on biopsy specimens (CLO test)), 4) DNA detection (polymerase chain reaction (PCR)), and 5) IgG antibody detection (enzyme-linked immunosorbent assay (EIA) and Western blotting (WB)). Results: This study showed that two positive tests out of five tests, based on different principles, were most reliable for predicting the H. pylori infection. Most tests had specificities and predictive values for a negative result greater than 90%. The most important difference between the tests was the sensitivity and the predictive value for a positive result (PPV). WB, HLO, UBT, and PCR had sensitivities and PPV greater than 75%. Conclusions: The non-invasive tests UBT and WB are reliable, both alone and in combination, and they are recommended for the pre-endoscopic diagnosis of H. pylori. WB is recommended as a confirmative test for antibody detection by EIA. When patients have an upper endoscopy, we recommend taking biopsy specimens for culture and histology because of the additional information obtained about susceptibility, virulence determinants, and morphology, including the degree of inflammation. [ABSTRACT FROM AUTHOR]