Complement activation in dialysis: effects on cytokines, lymphocyte activation and beta 2 microglobulin.

Anaphylatoxins generated by complement activation by filter membranes are present in plasma during hemodialysis (HD). In the presence of endotoxins which may contaminate the dialysate, they can trigger monocytes to produce interleukin-1 (IL-1) and tumor necrosis factor (TNF), with detrimental effects for the patients. We have investigated whether or not the use of complement activating (cuprophan) and non- (or less-) activating membranes (polysulfone, polymethylmethacrylate or polyacrylonitrile) per se influences cytokine levels in HD patients. Our results indicate that if a sterile bicarbonate solution is used as dialysate, there are no significant increases in IL-1, TNF, interleukin-2 (IL-2) and soluble IL-2 receptors (sIL-2r) throughout HD, even with cuprophan membranes. Moreover even a prolonged use of this membrane (three months) did not change pre-dialysis levels of cytokines and receptors. Use of complement activating membranes also does not influence beta 2 microglobulin levels.

Characterization of the response of in vitro cultured Myrtus communis L. plants to high concentrations of NaCl.

Effect of salt stress was examined in in vitro shoot cultures of Myrtus communis L. a species of the Mediterranean maquis. To determine the effects of high salt concentrations on myrtle plantlets and contribute toward understanding the mechanisms adopted from this species to counteract soil salinity, in vitro rooted shoots were transferred to a liquid culture medium containing 0, 125 or 250 mM NaCl for 30 days. After 15 and 30 days of in vitro culture, shoot and root growth, chlorosis and necrosis extension, chlorophylls, carotenoids, proline, arginine, cysteine and total sugars content, as well as guaiacol peroxidase (G-POD, EC 1.11.1.7) and ascorbate peroxidase (APX, EC 1.11.1.11) activities were determined. In treated plants shoot and root growth, as well as chlorophyll content, significantly decreased, while carotenoids content was not affected by the NaCl treatment. Among osmolytes, proline did not significantly increase, arginine and cysteine decreased, while total sugars were found to be higher in the treated plants than in the control. Enhancement of G-POD and APX activities was positively related to increasing salt concentrations in the culture media, regardless of the exposure time. Salt-treated plants did not show significant changes in lipid peroxidation or DNA fragmentation after 30 days salt treatment, regardless of the NaCl concentrations applied. The results represent a contribution towards understanding the mechanisms adopted by this species to high salinity.

Periodic acid Schiff (PAS) positivity in fetal erythroblasts.

The smears of 26 fetal blood samples taken for prenatal diagnosis were stained for the PAS reaction. Twelve out of 26 cases were subsequently found to be normal and 14 were found to be affected by different abnormalities; 83.4% of normal cases and 92.8% of abnormal cases showed moderate positivity to the PAS reaction. A higher percentage of PAS positive erythroblasts was found in the abnormal cases (p less than 0.01). Five cases with a percentage greater than 10% also showed a very high percentage of erythroblasts. No linear correlation was found between PAS positivity and erythroblastosis either in the normal or the abnormal cases, but pooling them resulted in a correlation between PAS positivity and erythroblastosis (r = 0.536; p less than 0.005). PAS positivity was most often diffuse and scored 1+. Since erythroblastosis is considered an indirect sign of fetal liver erythropoiesis, the hepatic environment and its peculiar hemopoiesis could play a role in producing a cohort of PAS positive erythroblasts.

Effect of UVB plus tar therapy on serum levels of interleukin-2 receptors in patients with psoriasis.

Baseline serum levels of interleukin-2 receptor (IL2R) were measured in 65 patients with active psoriasis. IL2R levels in psoriatic patients were significantly higher than in healthy controls (582.4 +/- 289.23 u/ml vs. 369.64 +/- 111.10 u/ml; P less than 0.05), but did not differ statistically from values found in an atopic dermatitis control group (619.88 +/- 254.27 u/ml). Sex, age and severity of the disease do not affect levels of IL2R. The same IL2R levels were measured in 26 psoriatic patients receiving UVB plus tar therapy. This therapy, continued until clinical remission, lowered IL2R levels to values comparable to controls. This decrease may be due to an immunosuppressive effect of therapy.