PubMed Health⌕ Search

Biomedical subjects

C Guastoni

Publications and source records attributed to C Guastoni.

7 recordsLinked to original sources
PubMed1992

Uremic inhibitors of erythropoiesis: a study during treatment with recombinant human erythropoietin.

The effects of increasing amounts of uremic sera (US) on the growth of erythroid progenitor cells [burst-forming unit erythroid (BFU-E)] collected from peripheral blood of normal subjects were evaluated to assess the potential role of uremic inhibitors of erythropoiesis during a treatment with recombinant human erythropoietin (r-HuEpo). US were collected from 8 patients on regular dialysis with marked anemia (Hb 6 +/- 0.5 g%) before and after a treatment with high doses of r-HuEpo (from 300 to 525 U/kg/week). Standard cultures for BFU-E were performed in alpha-metylcellulose with fetal calf serum (FCS) and 4 U/ml of r-HuEpo (Cilag, Ortho). In successive cultures, US were added at increasing amounts to the standard culture in order to assess a possible inhibitory effect on BFU-E growth. Finally, in order to assess a possible lack of stimulatory factors, we partially substituted FCS with US. The addition of US collected either before or after therapy with r-HuEpo to the standard culture had no effect on the growth of BFU-E. Vice versa, the number of cultured BFU-E decreased when FCS was partially substituted with US collected before r-HuEpo. This effect was not evident when FCS was partially substituted with US collected after r-HuEpo. No significant differences were recorded in the tested sera collected before and after therapy considering erythropoietin levels and amino acid levels. We hypothesized that some other factors with erythropoietic stimulatory activity (burst-promoting activity?) may be deficient in uremic patients with marked anemia and can be induced during therapy with r-HuEpo.

Adult↗
PubMed1991

High-flux acetate haemodialysis: a single-centre experience.

One hundred haemodialysed patients have been treated for 4 h thrice weekly by acetate haemodialysis with high-flux dialysers (HAHD) 1.4-1.8 m2 and automated ultrafiltration control for 18.9 +/- 8.3 months. The aim of the study was to evaluate the efficacy of treatment as regards urea and beta 2-microglobulin removal, cardiovascular stability, acid-base balance and plasma Il-1 variations. Moreover medium-term observation of both lipid profile and basal beta 2-microglobulin concentrations were performed. With our current adequacy criteria (urea clearance greater than or equal to 120 l/week; KT/V greater than or equal to 1.2; beta 2-microglobulin removal greater than or equal to 150 mg/treatment), the occurrence of hypotension was 6% during 24,500 treatments. Cardiovascular stability was preserved by the increase of total peripheral resistances in response to cardiac output decrease. No disturbances of acid-base parameters were observed in spite of plasma acetate concentrations greater than 6 mmol/l. No variations of plasma Il-1 occurred during the session or 2 h later.

Acetates↗
PubMed1990

Erythrocyte ferritin in patients on chronic hemodialysis treatment.

Serum ferritin (SF) and erythrocyte ferritin (EF) were evaluated in 35 patients on chronic hemodialysis treatment (CHD), in 45 healthy subjects and in 22 nonnephropathic females with iron deficiency anemia. Twenty-five CHD patients with basal SF less than 500 micrograms/l were treated orally with 200 mg of Fe2+ for 2 months and the positive (hemoglobin increase greater than 1 g/dl) or negative response to the therapy was correlated to the basal levels of SF and EF. Three groups of CHD patients could be defined on the basis of their basal SF levels (hypo-, normo- or hyperferritinemic). Nine patients with increased SF levels had also EF levels significantly higher than the other CHD patients and controls since they were probably iron-overloaded. In the other 2 groups of CHD patients, EF levels were significantly higher than in controls for each level of SF probably because of the reduced utilization of iron by uremic bone marrow. Among the 25 treated CHD patients, only 5 responded to the therapy: 3 were hypoferritinemic while the other 2 responders had basal SF within the normal range. Four hypoferritinemic patients did not respond to the therapy. Four out of five responders had the lowest EF levels among CHD patients. EF measurement could be an important and useful test in detecting the presence of an iron deficiency erythropoiesis in CHD patients.

Adult↗
PubMed1985

Is the dialysate fluid source of complement activating factors?

To distinguish between membrane-induced and dialysate-induced mechanism of complement activation attending hemodialysis (HD), the C3a plasma level and blood neutrophil count profiles have been determined during procedures performed with noncellulosic membranes, as PAN and PMMA (with minimal complement-activating potential) and, by comparison, with new cuprophane (that displays the greatest complement-activating potential). Furthermore, PAN and PMMA membranes have been used in 2 other blood purification methods: high efficiency hemofiltration (HEHF), in which there is no dialysate on the other side of the membrane, and hemofiltration without substitution fluid and with reinfusion of dialysis-regenerated hemofiltrate (HWSF), in which the dialysate is separated from the blood circuit by the hemofiltrate circuit. In addition, sequential dialysis-ultrafiltration (UFD) experiments with PAN membranes have been performed, where dialysate was present only in the second part of the procedure. In all the HD and UFD procedures LAL test assays were performed on dialysate at the same times as C3a and neutrophil determinations. Our findings seem to suggest that the dialysate can be a source of complement activating factors; complement activation detectable by C3a plasma levels can ensue when LAL test-positive material is present in the dialysate.

Blood↗
PubMed1985

Haemofiltration without substitution fluid.

Haemofiltration at its best is able to give excellent clearances of solutes in a wide molecular weight range, but the need of large amounts of reliable substitution fluid makes this technique too expensive for more widespread application. In order to give an 'adequate' treatment by a safe, well tolerated, effective and comparatively cheaper method, haemofiltration without substitution fluid (HWSF) has been carried out. This method, consisting of the regeneration of appropriate amounts of pure convected plasma water by highly permeable, high surface area dialysis membranes, has been utilised for several months in four patients, with encouraging clinical results.

Adult↗