Genomic changes during chronic Helicobacter pylori infection.

The gastric pathogen Helicobacter pylori shows tremendous genetic variability within human populations, both in gene content and at the sequence level. We investigated how this variability arises by comparing the genome content of 21 closely related pairs of isolates taken from the same patient at different time points. The comparisons were performed by hybridization with whole-genome DNA microarrays.

Genome-wide analysis of transcriptional hierarchy and feedback regulation in the flagellar system of Helicobacter pylori.

The flagellar system of Helicobacter pylori, which comprises more than 40 mostly unclustered genes, is essential for colonization of the human stomach mucosa. In order to elucidate the complex transcriptional circuitry of flagellar biosynthesis in H. pylori and its link to other cell functions, mutants in regulatory genes governing flagellar biosynthesis (rpoN, flgR, flhA, flhF, HP0244) and whole-genome microarray technology were used in this study.

Helicobacter pylori flagellins have very low intrinsic activity to stimulate human gastric epithelial cells via TLR5.

Helicobacter pylori is a flagellated chronic pathogen, which colonizes the gastric mucus and mucosal cell surfaces. Flagella and motility are essential for the survival of this bacterium in the stomach environment. Flagellins of several bacterial species are potent activators of the human innate immune system by binding to TOLL-like receptor 5 (TLR5).

Inhibition of LPS-induced splenocyte proliferation by ortho-substituted polychlorinated biphenyl congeners.

Polychlorinated biphenyls (PCBs) are persistent environmental contaminants, and their ubiquitous nature has prompted studies of their potential health hazards. As a result of their lipophilic nature, PCBs accumulate in breast milk and subsequently affect the health of offspring of exposed individuals. Biological effects of PCBs in animals have mostly been attributed to coplanar congeners, although effects of ortho congeners also have been demonstrated.