Increased spontaneous apoptosis of CD4+CD25+ T cells in patients with active rheumatoid arthritis is reduced by infliximab.

Increased secretion of tumor necrosis factor-alpha (TNF-alpha), along with interleukin-1 (IL-1) and interleukin-6 (IL-6), is important in the pathogenesis of rheumatoid arthritis (RA). T regulatory CD4(+)CD25(+) cells play a role in maintaining self-tolerance by downregulating Th1-induced proinflammation. This function has been found to be altered in active RA, whereas anti-TNF-alpha therapy has been found to improve the suppressive abilities of these cells.

Photoinhibition in vivo of photosystem II reactions during development of the photosystems of wheat seedlings.

Photoinhibition of O2 evolution and reactions leading to millisecond-delayed light emission (ms-DLE) of chlorophyll by illumination of leaves with excess white light were investigated in wheat seedlings greened for different times in a special chamber with constant conditions (20 degrees C; CO2 and humidity). A sharp reduction in initial and steady state rates of O2 evolution and in the intensity of different components of ms-DLE under excess light on the stage of lag-phase of chlorophyll biosynthesis (4-6h of greening) were observed. An increasing stability of the oxygen-evolving process and ms-DLE of chlorophyll during formation of the thylakoid membrane photosystems (12-24 h of greening) was shown.