Comparison of micronuclei frequencies in mono-, bi- and poly-nucleated lymphocytes from subjects of a residential suburb and subjects living near a metallurgical plant.

Spontaneous baseline frequencies of micronuclei in mono-, bi- and poly-nucleated lymphocytes were analyzed, using the cytokinesis-block technique, in 103 subjects living in a residential suburb (Genova-Nervi), and in 203 subjects living in an urban industrialized area near a metallurgical plant and a coke factory (Genova-Cornigliano). Statistical analysis showed that the average frequency of micronucleated binucleated lymphocytes (MnBNL) was significantly higher (1.42-fold) in donors of Nervi than in donors of Cornigliano living in a contaminated environment. In contrast, the average frequency of micronucleated polynucleated lymphocytes (MnPNL) was significantly higher (1.66-fold) in donors of Cornigliano than in donors of Nervi. The existence in the whole population examined of a positive correlation between frequency of MnBNL and frequency of MnPNL and the absence of a positive correlation between frequency of bi- and poly-nucleated lymphocytes and frequency of MnPNL suggest that the formation of MnPNL is a consequence of genetic damage and not of mitotic errors arising during the division of bi- and poly-nucleated cells. In agreement with previous findings the frequency of MnBNL increased with age and was significantly higher in females than in males; unexpectedly it was higher in non-smokers/non-drinkers than in smokers/drinkers.

Long-term influence of dialysis treatment on beta 2-microglobulin, interleukin-2 R and tumour necrosis factor.

Recently much interest has been focused on the phenomena produced by the interaction between blood and dialytic membranes. The aim of this study was to evaluate beta 2-M, Il-2 and TNF changes in relation to the long-term use of different membranes (CU, PAN-AN69, PMMA, PS) and different dialytic treatments (HD, HDF, AFB). Plasma beta 2-M was significantly increased in patients dialysed with CU compared to synthetic membranes, and decreased in AFB compared to HD and HDF. Intradialytic changes of beta 2-M, corrected for haemoconcentration, resulted in a significant increase with CU and PMMA, while a decrease was found with PAN-AN69 and PS and during convective treatments, more evident during haemofiltration performed with sterile dialysate without acetate. I1-2R was increased in all patients compared to normal subjects, without any intradialytic change, regardless of the type of membrane used. TNF was in the normal range. The different decrease of beta 2-M observed with synthetic membranes, the stable intradialysis I1-2 R values during HD performed with membranes non-permeable to endotoxins and during AFB, and the absence of detectable TNF support the hypothesis that dialysate plays an important role in activating beta 2-M and cytokines, together with other factors.