Cell death at the intestinal epithelial front line.

The intestinal epithelium represents the largest epithelial surface in our body. This single-cell-layer epithelium mediates important functions in the absorption of nutrients and in the maintenance of barrier function, preventing luminal microorganisms from invading the body. Due to its constant regeneration the intestinal epithelium is a tissue not only with very high proliferation rates but also with very prominent physiological and pathophysiological cell death induction.

Ventricular repolarization during uni and biventricular pacing in normal subjects.

Background: The cardiac depolarization-repolarization process (D-REPP) may differ among various modes of cardiac pacing depending on the paced chamber(s) and lead position. We intended to assess the effect of different modes of cardiac pacing (left, right and biventricular) on the D-REPP as expressed in QRS, QT, peak-to-end of the T wave (PETW) and PETW/QT intervals and their dispersion. These intervals were compared during pacing and sinus rhythm.

Dimerization of Smac is crucial for its mitochondrial retention by XIAP subsequent to mitochondrial outer membrane permeabilization.

Following the apoptotic permeabilization of the outer mitochondrial membrane, the inter-membrane space protein second mitochondria-derived activator of caspases (Smac) is released into the cytosol. Smac efficiently promotes apoptosis by antagonizing x-linked inhibitor of apoptosis protein (XIAP), an inhibitor of caspases-9, -3, and -7, via a short NH(2)-terminal inhibitor of apoptosis protein (IAP) binding motif (AVPI). Native Smac dimerizes to form a highly stable and inflexible elongated arch, however, a functional role for this outstretched structure so far remained unknown.

Dietary polyphenols protect against N-nitrosamines and benzo(a)pyrene-induced DNA damage (strand breaks and oxidized purines/pyrimidines) in HepG2 human hepatoma cells.

Background: Dietary polyphenols have been reported to have a variety of biological actions, including anticarcinogenic and antioxidant activities.

Aim Of The Study: In the present study we investigated the protective effect of dietary polyphenols against N-nitrosodimethylamine (NDMA), N-nitrosopyrrolidine (NPYR) and benzo(a)pyrene (BaP)-induced DNA damage (strand breaks and oxidized purines/pyrimidines) in HepG2 cells.

Methods: Human hepatocellular carcinoma (HepG2) cells, which retain many specialized liver functions and drug metabolizing enzyme activities, were used as in vitro model for human hepatocytes.