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F Galli

Publications and source records attributed to F Galli.

104 records · Page 6Linked to original sources
PubMedDate not supplied

[Changes is Th1/Th2 balance in hemodialysis patients: effect of different membranes].

BACKGROUND: Hemodialysis (HD) patients present an immunodeficiency that is mainly related to the defect of cell-mediated immunity. We have previously shown the polarisation of T-helper cells toward the phenotype in HD treatment with cuprophan membrane. In the present study, we have examined the effect of a Vitamin E-coated dialyser (Excebrane, VE) on the activity of the two Th subsets. METHODS: We studied 8 healthy controls and 10 patients on RDT for at least 6 months with cellulose membrane (AC), then switched to HD-VE. Blood was collected from HD patients while on treatment with AC, and after 1 year of treatment with VE. CD4+ cells were isolated from peripheral blood mononuclear cells (PBMC) by negative selection, treating PBMC with a cocktail of anti-CD8, -CD16, -CD19, -CD36 and -CD56 antibodies labelled with magnetic beads, and passing them through a magnetic field. The collected Th cells were cultured for 48 h with and without phytohemagglutinin (PHA). IFNgamma and IL-4 were measured in the supernatant using the ELISA assay. RESULTS: The constitutive release of IL-4 by CD4+ cells was abated significantly by treatment with VE. IFNgamma released by mitogen-stimulated CD4+ recovered with VE. CONCLUSIONS: This study demonstrates that treatment with vitamin E-coated dialyser improves the defect of PBMC function associated with cellulose membrane dialyser consisting of altered spontaneous and mitogen-stimulated cytokine release. The effects of vitamin E-coated filter, in particular the recovery of reactive IFNgamma production by Th1 cells and the restriction of spontaneous IL-4 release by Th2 cells may have clinical importance.

Adult↗
PubMedDate not supplied

[A good vascular access allows an effective treatment].

Vascular access (VA) for dialysis is defined as the 'Achilles heel', but also the 'Cinderella' of dialysis, indicating the poor consideration of the problem whether in the surgical environment, or in incomprehensible way in that nephrologic. It can only aspire to the definition 'Fundamental detail'. However, presupposed effective dialysis is a blood flow rate of 300-350 mL/min. Good VA must be easy to prepare, long lasting, free from complications, and aesthetically acceptable and economical. The arteriovenous fistula (AVF) of Cimino and Brescia, from 1966, represents the gold standard and the model of comparison for other systems, more technologically advanced. It must be programmed with an adapted margin (1-2 months) to allow maturation and access certainty for the first puncture, and never carried out sooner than 14 days from the operation. It is known from hemodynamic studies that the good functional flow of the new fistula can already regain 400-500 ml/min in the first week, with cardiological implications like the increase in cardiac throw, in ejection fraction and in the cardiac index. Health workers, patients and dialysis staff must follow a continuous educational program to protect the VA and avoid 'routine and absent-minded management', a basis for its premature failure. The nephrologist must take the responsibility upon himself not to carry out 'medical malpractice'. In the Dialysis Center of Mantova, the VA 'road map' previews all patients (young and old, affections from mono or pluropathology), first the fistula to the wrist, then the cephalic proximal. It follows the basilic vein transposition, the vascular graft to the arm or to the groin, as an alternative to peritoneal dialysis. The permanent central venous catheter (CVCp) is the last choice in patients with reduced life expectancy, heart failure, neoplastic patients with vascular patrimony destroyed by chemotherapy and ischemic lesions produced by the fistula. There were 180 afferent prevailing patients at the Mantova Dialysis Center . The natural fistula rate was 91%, grafts 7% and CVCps 2%. Between 2000 and 31 March 2004 we prepared 367 VAs. Average patient age was 65 yrs, range 20-90 yrs; 59% male and 41% female. Eighty-eight percent of operations were performed by the nephrologist (distal fistula, rescue and cephalic proximal) and 12% by the vascular surgeon (basilic vein transposition, graft in PTFE stretch to the arm and to the groin and permanent catheter in the jugular vein). The fistula with native veins was the better solution, the graft must be prepared after the exhaustion of natural possibilities, and the CVCp, for serious complications (inadequate flow and infections), must be the last alternative.

Catheterization↗
PubMedDate not supplied

Bicarbonate versus lactate buffer in peritoneal dialysis solutions: the beneficial effect on RBC metabolism.

OBJECTIVE: Using the erythrocyte as a model for other kinds of cells not directly exposed to peritoneal dialysis (PD) solutions, we investigated the tolerance of the cell metabolism to lactate and bicarbonate buffers. DESIGN: We studied, in vivo (in two groups of 5 PD patients each) and in vitro, the Embden-Meyerhof pathway (EMP) because it represents a potential target for the unphysiological effects of lactate or bicarbonate buffers. The EMP is the main glucose-utilizing route in the red blood cell (RBC), producing energy and reducing power. METHODS: The enzymatic activities of the key steps in the glycolytic pathway and the energy charge (EC), determined by the levels of phosphorylated adenine nucleotides, were investigated spectrophotometrically and by high performance liquid chromatography (HPLC) in two groups of patients undergoing lactate (L-group) and bicarbonate (B-group) PD, respectively. The in vitro effects of both bicarbonate and lactate buffers on some EMP enzyme activities and energy production were determined. Cellular pH (pHi) was also investigated. RESULTS: The B-group showed an EC value near the control levels, while in the L-group a significantly lower EC value was observed (t-test: p < 0.05 vs both B-group and controls). The key enzymes in the EMP, and in particular hexokinase, were higher in the L-versus B-group (p < 0.03 for the comparison of the Hk mean values). As demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, the bound form of glyceraldehyde-3-phosphate dehydrogenase (G-3-PD), an inactive form of this EMP enzyme, was significantly higher in the L-group with respect to the B-group (p < 0.004). In the in vitro experiments, high lactate concentrations acutely inhibited the key enzymatic steps of glycolysis, producing a significant decrease in glucose consumption and adenosine triphosphate production. These effects were not observed when bicarbonate was used in the incubations. Both in vivo and in vitro lactate, but not bicarbonate, induce a significant drop in pHi (p < 0.05). Decreased levels of pHi like those observed in the lactate-incubated RBC were demonstrated to be able to inhibit G-3-PD activity (25 +/- 2%) here used as an indicator of the actual decrease in pH. CONCLUSION: This study provides evidence for a damaging action of lactate with respect to bicarbonate buffer on the RBC metabolism. This condition was demonstrated observing a cell energy depletion, which coincides in vitro with an acute EMP impairment; the lactate accumulation together with the consequent lowering of pHi seem to be responsible for this effect, which was not observed when bicarbonate was used instead of lactate.

Adenine Nucleotides↗