Flow-cytometric study of granulocyte activation during hemodialysis with different membranes.

Flow cytometry allows an easy quantitation of reactive oxygen intermediate production and of C3bi receptor expression by granulocytes, thus providing a clinical tool to evaluate the hemodialysis-related granulocyte activation. In this flowcytometric study, we analyzed the effects of cellulosic, synthetic polyacrylonitrile, and ethylene-vinyl-alcohol dialyzers on granulocyte membrane and function. Our results confirmed the data reported in the literature on granulocyte activation secondary to cellulosic membranes and the better biocompatibility of synthetic dialyzers that did not increase C3bi receptor expression and reactive oxygen intermediate generation by granulocytes. The flow-cytometric analysis of granulocyte activation might be the method of choice to identify the best patient/membrane interaction in every single patient.

The effects of prolonged cardiopulmonary bypass on cell-mediated immunity.

Studies of T-cell subsets (CD3+, CD4+, CD8+, CD8+ CD57+ cells), lymphocyte response to concanavalin A (Con A), phytohaemoagglutinin (PHA) and the alterations of white cell membranes shown by scanning electronic microscope (SEM) in 51 patients who underwent cardiac operation were performed. Out of these 51 unselected patients, for 16, duration of CPB was < or = 110 min (group A), while for the other 35 (group B) it was prolonged (> 110 minutes). Although variations of the lymphocyte subset observed between groups A and B were slightly significant (p < 0.05 before CPB and on postoperative day 7), the T-cell reactivity in group B in comparison to that of group A did not normalize by postoperative day 7 regardless of stimulation with PHA or with Con A. With the use of the SEM, the folded aspect of lymphocyte surface decreased after surgery in about 71% (group A) and 78% (group B) of the observed cells. The outcome of the immunological effects given by our studies could have been due to an elongated CPB even if there need to be taken into consideration multifactorial influences, i.e. biological, pharmacological and hormonal hypotheses, and rapid changes in CPB-micro-environment.

[Plasma levels of atrial natriuretic peptide and its relationship with arterial blood pressure before and after peritoneal dialysate infusion]. / Livelli plasmatici del peptide natriuretico atriale e rapporti con la pressione arteriosa prima e dopo il carico del liquido di dialisi peritoneale.

The acute modifications of atrial natriuretic peptide (ANP) plasma levels due to intraperitoneal dialysate infusion and the relationship between ANP and arterial blood pressure were studied in 17 patients on continuous ambulatory peritoneal dialysis (CAPD). ANP plasma levels were 159.18 +/- 87.06 pg/ml 30' minutes after 2.000 ml of peritoneal dialysate filling (t = 2.55; p less than 0.02). There was no correlation between ANP and arterial blood pressure neither before (r = -0.10; p = n.s.), nor after intraperitoneal dialysate infusion (r = 0.05; p = n.s.).

[Cardiac rhythm disorder in infection caused by cytomegalovirus in patients with kidney transplant]. / Turbe del ritmo cardiaco in corso di infezione da citomegalovirus nei trapianti di rene.

A higher incidence of arrhythmias was observed in 16 renal allograft recipients infected with Cytomegalovirus (CMV), as compared to 26 patients who were transplanted during the same period and did not contract the infection (43.7% vs. 3.8%; p less than 0.01). There was a highly significant difference in the incidence of sinus tachycardia (37.5% infected vs. 0% not infected; p less than 0.005), while the incidences of atrial fibrillation and ventricular ectopic beats were not significantly different. The arrhythmias always appeared in the early phases of the infection and disappeared after a certain period, lasting from one week to months. It is proposed that arrhythmias arising during CMV infection may be due to a myocardial CMV involvement.