Cellular Aspects of Shigella Pathogenesis: Focus on the Manipulation of Host Cell Processes.

Shigella is a Gram-negative bacterium that is responsible for shigellosis. Over the years, the study of Shigella has provided a greater understanding of how the host responds to bacterial infection, and how bacteria have evolved to effectively counter the host defenses. In this review, we provide an update on some of the most recent advances in our understanding of pivotal processes associated with Shigella infection, including the invasion into host cells, the metabolic changes that occur within the bacterium and the infected cell, cell-to-cell spread mechanisms, autophagy and membrane trafficking, inflammatory signaling and cell death. This recent progress sheds a new light into the mechanisms underlying Shigella pathogenesis, and also more generally provides deeper understanding of the complex interplay between host cells and bacterial pathogens in general.

Effect of remifentanil on nucleotide-binding oligomerization domain 1 mRNA expression in rats with renal ischemia-reperfusion injury / 中华麻醉学杂志

Objective To investigate the effect of remifentanil on nucleotide-binding oligomerization domain 1 (NOD1) mRNA expression in rats with renal ischemia-reperfusion (I/R) injury.Methods Sixty male Sprague-Dawley rats,weighing 220-250 g,were randomly divided into 3 groups (n =20 each):sham operation group (S group),I/R group and remifentanil group (R group).Renal ischemia was induced by occlusion of bilateral renal arteries for 45 min followed by 24 h reperfusion in groups I/R and R.Remifentanil 1.0 μg· kg-1 · min-1 was infused until 30 min of reperfusion starting from 15 min before ischemia in group R,while the equal volume of normal saline was given instead in S and I/R groups.The animals were sacrificed at 15 min before ischemia and at 3,6,24 h of reperfusion and the kidneys were removed for microscopic examination and polymorphonuclear leukocyte (PMN) count and for measurement of NOD1 mRNA expression (by RT-PCR).The apoptotic rate was determined by flow cytometry double staining method.Results Compared with group S,NOD1 mRNA expression was up-regulated,and the apoptotic rate and PMN count were significantly increased at each time point during reperfusion in group I/R,and the apoptotic rate and PMN count were significantly increased at each time point during reperfusion,and NOD1 mRNA expression was up-regulated at 6 and 24 h of reperfusion in group R (P ＜ 0.01).Compared with I/R group,NOD1 mRNA expression was down-regulated,and the apoptotic rate and PMN count were significantly decreased at each time point during reperfusion (P ＜ 0.05 or 0.01),and the pathological changes were significantly attenuated in group R.Conclusion Remifentanil can reduce the renal I/R injury by down-regulating the expression of NOD1 mRNA and inhibiting inflammatory response and apoptosis.