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The babA2 and cagA genes were investigated in 208 Brazilian Helicobacter pylori strains. A strong association between babA2 and duodenal ulcer or gastric carcinoma was observed, even after adjusting for confounding factors, such as age, gender, and cagA status. cagA-positive strains were also independently associated with H. pylori-related diseases.Helicobacter pylori infection is one of the most common chronic bacterial infections worldwide. Although most infected persons remain asymptomatic, 15 to 20% of H. pylori-positive individuals will develop a peptic ulcer, gastric carcinoma, or mucosa-associated lymphoid tissue lymphoma (19). However, it remains unclear why only a minority of infected patients develop the severe associated diseases. This phenomenon may be due to differences in host genetics, environmental factors, and the virulence of bacterial strains.There is now evidence for the existence of different strains of H. pylori with different degrees of virulence (2,3,18). The cytotoxin-associated gene cagA was the first gene found to be differentially present in H. pylori isolates and is considered a marker for the presence of the cag pathogenicity island (4). In addition to other putative virulence properties encoded by the cag pathogenicity island, several genes of the island encode proteins, such as interleukin-8, that enhance the gastric inflammatory response to the infection.A cagA-positive status has been associated with severe clinical outcomes in some Western countries (3,14,18). Conversely, since the majority of H. pylori-infected individuals in Asian countries harbor cagA-positive strains, associations of cagA status and diseases are not observed in Asia (11,20). The recently described blood group antigen-binding adhesin BabA has been shown to mediate adherence of H. pylori to Lewis b (␣-1,3/4-difucosylated) receptors on gastric epithelium (8). Although three bab alleles have been identified (babA1, babA2, and babB), only the babA2 gene product is necessary for Lewis b binding activity (8,16). Studies in Western countries have demonstrated associations between babA2-positive status and duodenal ulcer as well as gastric carcinoma (7). However, in Asian countries, most of the circulating H. pylori strains are babA2 positive, whether or not they were isolated from asymptomatic or diseased patients (9,10,12,20). In addition to these differences between Western and Eastern countries, the prevalence of babA2-positive H. pylori strains also seems to vary among the Western populations, being much lower in patients from Portugal (13) than in those from Germany, the United States, or Colombia (7, 20). Since there are few studies on this subject, specifically evaluating patients with gastric carcinoma, the frequency of babA2 H. pylori strains may vary around the world and because the clinical relevance of babA2-positive strains has not been determined in Brazil, we investigated associations between babA2 and cagA genotypes and different H. pylori infection outcomes, adjusting for confounding factors.H Two ...

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Comparison of gastric carcinoma and gastritis isolates showed the presence of genes, probably carcinoma associated (JHP947 and JHP940), that are situated in a Helicobacter pylori genome region (45 kb in J99 and 68 kb in 26695) called the "plasticity region." This region presents a great variability of DNA sequences. We investigated, by PCR, the presence of the JHP940 and JHP947 genes, as well as the presence of a third gene which seems to be associated with gastritis (HP986), on H. pylori strains isolated from 200 Brazilian patients, 79 of whom had gastric carcinomas and 53 of whom had duodenal ulcers, to confirm this association. Gastritis isolates (n ‫؍‬ 68) were included as a control. We also evaluated if these genes were related to the virulenceassociated cagA genotype. The present methodology did not permit definitive conclusions to be reached regarding the association between the JHP940 gene and gastric carcinoma or between the HP986 gene and gastritis. However, we showed that the JHP947 gene might be implicated in the development of both duodenal ulcer and gastric carcinoma. The presence of the JHP947 gene was associated with the cagA-positive genotype. The JHP947 gene is a novel virulence marker candidate of H. pylori.

Male rats, 30 d old, were treated with the antiestrogen ICI 182,780 (3-150 d) to determine sequences of events leading to testicular atrophy and infertility. Plasma testosterone and LH concentrations were unchanged. ICI 182,780 induced dilation of efferent ductules as early as 3 d post treatment, and the dilation increased over time, resulting in an overall increase of 200% in tubule diameter. A gradual reduction in height of the ductule epithelium was observed; however, the microvilli height increased up to d 73 but subsequently decreased. A transient increase in lysosomes in nonciliated cells was seen from d 15 to d 100. Testicular weight increased by d 45 and seminiferous tubules were dilated by d 52. These effects on testes persisted until d 100, but on d 150 the weight decreased and severe atrophy was observed. These testicular effects were probably owing to accumulation of fluid following inhibition of reabsorption in the efferent ductules, similar to the ER-alpha knockout mouse. In agreement with this conclusion, there was a decrease in Na+-H+ exchanger-3 mRNA and protein, which is consistent with previous studies showing that ER is required for expression of Na+-H+ exchanger-3 and ultimately fluid reabsorption in the efferent ductules.