32 results on '"Stefoni S"'
Search Results
2. Platelet activation and PDGF-AB release during dialysis.
- Author
-
Donati, G, Cianciolo, G, D'Addio, F, Colì, L, La Manna, G, Feliciangeli, G, and Stefoni, S
- Published
- 2002
- Full Text
- View/download PDF
3. Is ß2-Microglobulin-Related Amyloidosis of Hemodialysis Patients a Multifactorial Disease? a New Pathogenetic Approach
- Author
-
Cianciolo, G., Colì, L., La Manna, G., Donati, G., D'addio, F., Comai, G., Ricci, D., Dormi, A., Wratten, M., Feliciangeli, G., and Stefoni, S.
- Abstract
Purpose ß2-microglobulin amyloidosis (Aß2M) is one of the main long-term complications of dialysis treatment. The incidence and the onset of Aß2M has been related to membrane composition and/or dialysis technique, with non-homogeneous results. This study was carried out to detect: i) the incidence of bone cysts and CTS from Aß2M; ii) the difference in Aß2M onset between cellulosic and synthetic membranes; iii) other risk factors besides the membrane.Methods 480 HD patients were selected between 1986 to 2005 and grouped according to the 4 types of membranes used (cellulose, synthetically modified cellulose, synthetic low-flux, synthetic high-flux). The patients were analyzed before and after 1995, when the reverse osmosis treatment for dialysis water was started at our center, and the incidence of Aß2M was compared between the two periods. Routine plain radiography, computer tomography (CT) and nuclear magnetic resonance imaging (MRI) as well as electromyography were used to investigate the clinical symptoms.Results Bone cysts occurred in 29.2% of patients before 1995 vs. 12.2% after 1995 (p<0.0001). CTS occurred in 24% of patients before 1995 vs. 7.1% after 1995 (p<0.0001). Bone cysts and CTS occurred in older patients, who began dialysis at a late age, with high CRP, low albumin, low residual GFR, and low Hb. Cox regression analysis showed that the risk factor for bone cysts was high CRP (RR 1.3, p<0.01), while albumin (RR 0.14, p<0.0001) and residual GFR (RR 0.81, p<0.0001) were revealed to be protective factors. Cox analysis for CTS confirmed CRP as a risk factor (RR 1.2, p<0.01), and albumin (RR 0.59, p<0.0001) and residual GFR (RR 0.75, p<0.0001) as protective factors. The comparison obtained between membranes did not suggest any protective effect on Aß2M.Conclusions The findings that the inflammatory status as well as low albumin and the residual GFR of the uremic patient are predictive of Aß2M lesions suggests that Aß2M has a multifactorial origin rather than being solely a membrane- or technique-related side effect.
- Published
- 2007
- Full Text
- View/download PDF
4. A Mathematical Model for the Prediction of Solute Kinetics, Osmolarity and Fluid Volume Changes during Hemodiafiltration with On-Line Regeneration of Ultrafiltrate (HFR)
- Author
-
Ursino, M., Colì, L., Magosso, E., Capriotti, P., Fiorenzi, A., Baroni, P., and Stefoni, S.
- Abstract
Hemodiafiltration with on-line regeneration of ultrafiltrate (HFR) is a technique indicated for the treatment of dialysis patients affected by inflammatory syndrome and malnutrition. In the present work, a mathematical model, which describes intradialytic fluid and solute kinetics during standard diffusive dialysis, has been adapted to analyze solutes and fluid dynamics during HFR. The model is an improved version of our previous ones, and represents a good compromise between simplicity and reliability. It considers the intradialytic kinetics of sodium, potassium and urea, and two body fluid compartments: intracellular and extracellular. Moreover, the model includes simple equations to predict the intradialytic time pattern of osmolarity.The model has been experimentally validated by using 9 HFR sessions on 9 patients (one per each patient), comparing the time course of plasma solutes and osmolarity measured every 30 minutes during HFR, with those predicted by the model. Predictions are performed a priori, i.e., without any parameter adjustment, but just starting from knowledge of a few quantities (plasma sodium, potassium, urea, osmolarity and body weight) at the beginning of the session.The average deviations between model and real data (sodium: 1.9 mEq/L; potassium: 0.32 mEq/L; urea: 1.04 mmol/L; osmolarity: 5.02 mosm/L) are of the same order as measurement errors and similar to those obtained using our previous models in standard and profiled hemodialysis. Moreover, the prediction on sodium concentration only scarcely worsens (from 1.9 to 2.02 mEq/L) if default values are used for the initial value of other solutes in blood (i.e., if the algorithm uses only initial body weight and initial sodium concentration in plasma).The results confirm the good predictive capacity of the model in HFR, and suggest its possible innovative use to optimize sodium balance in HFR, from knowledge of only the sodium concentration in the ultrafiltrate. (Int J Artif Organs 2006; 29: 1031–41)
- Published
- 2006
- Full Text
- View/download PDF
5. Molecular Adsorbent Recirculating System (MARS) Application in Liver Failure: Clinical and Hemodepurative Results in 22 Patients
- Author
-
Stefoni, S., Colì, L., Bolondi, L., Donati, G., Ruggeri, G., Feliciangeli, G., Piscaglia, F., Silvagni, E., Sirri, M., Donati, G., Baraldi, O., Soverini, M.L., Cianciolo, G., Boni, P., Patrono, D., Ramazzotti, E., Motta, R., Roda, A., Simoni, P., Magliulo, M., Borgnino, L.C., Ricci, D., Mezzopane, D., and Cappuccilli, M.L.
- Abstract
Purpose Acute liver failure (ALF) and acute on chronic liver failure (ACLF) still show a poor prognosis. MARS was used in 22 patients with ALF or ACLF to prolong patient survival for liver function recovery or as a bridge to transplantation.Design Evaluation of depurative efficiency, biocompatibility, hemodynamics, encephalopathy (HE) and clinical outcome.Procedures During 71 five-hour sessions we evaluated (0', 60', 120', 180', 240', 300'): bilirubin, ammonia, cholic acid (CCA), chenodeoxycholic acid (CCDCA), leukocytes, platelets, hemoglobin and mean arterial pressure (MAP). Serum creatinine, electrolytes, cardiac output, cardiac index (bioimpedence) and HE (West Haven Criteria score) were evaluated at 0' and 300'. Statistical methods and outcome measures: Student's t-test for pre- vs. end-session values was used. For bilirubin and ammonia the correlation test was made between pre- and end-session values and between pre-session values and removal rates (RRS).Main Findings Survival was 90.9% at 7 days, 40.9% at 30 days. Pre- vs. end-session: bilirubin from 37.2±12.5 mg/dL to 24.9±8.9 mg/dL (p<0.01), ammonia from 88.0±60.4 µmol/L to 43.6±32.9 µmol/L (p<0.01), CCA from 42.8±21.0 µmol/L 18.2±9.8 µmol/L (p<0.01), CCDCA from 26.3±6.3 µmol/L to 15.7±7.6 µmol/L (p<0.01). The correlation test between pre-session values of bilirubin and ammonia vs. RRSwas respectively 0.32 (p=0.01) and 0.30 (p=0.04). Leukocytes, platelets and hemoglobin remained stable. MAP increased from 82.0±12.0 mmHg to 87.0±13.0 mmHg (p<0.05), West Haven Criteria score decreased from 2.7±0.7 to 0.7±0.7 (p<0.001).Conclusion MARS treatment led in all patients to an improvement of clinical, hemodynamic and neurological conditions, with significant reduction in the hepatic toxins blood level. Treatment biocompatibility and tolerance were satisfactory
- Published
- 2006
- Full Text
- View/download PDF
6. Clinical Application of Sodium Profiling in the Treatment of Intradialytic Hypotension
- Author
-
Colì, L., Ursino, M., Donati, G., Cianciolo, G., Soverini, M.L., Baraldi, O., La Manna, G., Feliciangeli, G., Scolari, M.P., and Stefoni, S.
- Abstract
Background Intradialytic hypotension is mainly induced by the removal of extracellular sodium during dialysis, which impairs intravascular fluid refilling and reduces blood volume. To counter this complication we tested a new kind of profiled hemodialysis (PHD) consisting of the intradialytic modulation of dialysate sodium concentration according to individual profiles set up using a new mathematical model for intradialytic solutes and water kinetics. The clinical aim of this PHD is to stabilize blood pressure maintaining higher blood volume values than standard dialysis treatments. We clinically validated PHD in comparison with constant dialysate sodium dialysis (CHD).Methods Twenty hypotensive dialysis patients underwent one PHD and one CHD session maintaining the same dialysis length, sodium mass removal and body weight decrease. A new mathematical model was used to define both the dialysate sodium profiles for PHD and the constant dialysate sodium for CHD. Percent blood volume variation (Crit-line), mean blood pressure, heart rate, cardiac output (Doppler-echocardiography) were monitored intradialitically.Results Cardiovascular stability improved on PHD as compared with CHD sessions; blood volume and cardiac output during PHD showed a lower decrease than on CHD, the differences statistically significant (from 30' and 60' respectively). Mean blood pressure was, at all time intervals, more stable on PHD than on CHD and was accompanied, on PHD, by a lower heart rate increase (differences statistically significant).Conclusions This study shows that PHD performed using dialysate sodium profiles elaborated by our mathematical model obtains, in hypotensive patients, a higher hemodynamic intradialytic stability than CHD, probably due to a higher stabilization of blood volume.
- Published
- 2003
- Full Text
- View/download PDF
7. Inflammatory Response of a New Synthetic Dialyzer Membrane. a Randomised Cross-over Comparison between Polysulfone and Helixone
- Author
-
Stefoni, S., Colì, L., Cianciolo, G., Donati, G., Ruggeri, G., Ramazzotti, E., Pohlmeier, R., and Lang, D.
- Abstract
Hemodialysis patients suffer from chronic inflammation due to intradialytic contact of blood with artificial materials. The FX 60 dialyzer which belongs to the new FX-class series of dialyzers is composed of the new membrane Helixone®. This membrane is derived from the original Fresenius Polysulfone®membrane. The FX-class design is based on modified geometry of fibres and housing and has resulted in a new dialyzer with improved efficiency, safety and ease of handling compared to the F series (F 60S) dialyzer.The aim of the study was to investigate whether the biocompatibility pattern in terms of inflammatory parameters of the new type of polysulfone dialyzer has changed compared to the standard. A clinical in vivo study was conducted to compare the intradialytic inflammatory response of the two dialyzers, FX 60 and F 60S. Eight chronic dialysis patients were selected for the study: mean age 65.5±15.5 years, mean time on dialysis 100±95 months. The randomized cross-over study involved a treatment period of 2 weeks (total 6 sessions), one week with each dialyzer, starting with one or the other according to the randomization scheme. Blood samples were taken at 0 (T0), 15, 60, and 240 minutes to evaluate white blood cell (WBC) count, complement factor C5a, leukocyte elastase, soluble intercellular adhesion molecule 1 (sICAM-1), platelet count, C-reactive protein (CRP).At 15 min, WBC count showed a comparably, low decrease for both dialyzers: -7.6 % for FX 60 versus -6.6 % for F 60S, p=not significant (ns). At the same time the C5a concentration decreased from 15.0±7.5 ng/ml to 13.5±6.7 ng/ml (p=ns) for FX 60, and from 15.1±12.5 ng/ml to 14.9±25.0 ng/ml for F 60S (p=ns). The elastase concentration progressively increased over time with no statistical difference between the two dialyzers. The levels of sICAM-1, CRP, and platelet count were similar at each time point for both dialyzers, varying around the baseline values (p=ns).No significant difference emerged in terms of inflammatory response between the two dialyzers, demonstrating that the biocompatibility of the F-series was maintained in the FX-class series of dialyzers and is independent of design factors.
- Published
- 2003
- Full Text
- View/download PDF
8. Mathematical Modeling of Solute Kinetics and Body Fluid Changes during Profiled Hemodialysis
- Author
-
Ursino, M., Colì, L., Brighenti, C., De Pascalis, A., Chiari, L., Dalmastri, V., La Manna, G., Mosconi, G., Avanzolini, G., and Stefoni, S.
- Abstract
A mathematical model of solute kinetics oriented to improve hemodialysis treatment is presented. It includes a two-compartment description of the main solutes (K+, Na+, Cl–, urea, HCO–3, H+, CO2), acid-base equilibrium through two buffer systems (bicarbonate and non-carbonic buffers) and a three-compartment model of body fluids (plasma, interstitial and intracellular). The main model parameters can be individually assigned a priori, on the basis of body weight and plasma concentration values measured before beginning the session.Model predictions are compared with clinical data obtained during 11 different hemodialysis sessions performed on six patients with profiled sodium concentration in the dialysate and profiled ultrafiltration rate. In all cases, the agreement between the time pattern of model solute concentrations in plasma and clinical data turns out fairly good as to urea, sodium, chloride and potassium kinetics. Finally, the time patterns of plasma bicarbonate concentration and pH can be reproduced fairly well with the model, provided CO2concentration remains constant. Only in two sessions, blood volume was directly measured in the patient, and in both cases the agreement with model predictions was good.In conclusion, the model allows a priori computation of the amount of sodium removed during hemodialysis, and may enable the prediction of plasma volume changes and plasma osmolarity changes induced by a given sodium concentration profile in the dialysate and by a given ultrafiltration profile. Hence, it can be used to improve the dialysis session taking the characteristics of individual patients into account, in order to minimize intradialytic imbalances (such as hypotension or disequilibrium syndrome).
- Published
- 1999
- Full Text
- View/download PDF
9. Effects of Dialysis Membrane Nature on Intradialytic Phagocytizing Activity
- Author
-
Colì, L., Tumietto, F., De Pascalis, A., La Manna, G., Zanchelli, F., Isola, E., Perna, C., Raimondi, C., De Sanctis, L.B., Marseglia, C.D., Costigliola, P., and Stefoni, S.
- Abstract
Blood-membrane contact in the extracorporeal circuit affects the activation of many biological systems. Among these, phagocytizing activity has been reported to be influenced by the nature of the hemodialysis membrane used, whether cellulosic or synthetic.This work reports on an ex-vivo, comparative test between cellulosics and synthetics concerning the effects of blood-membrane contact on the polymorphonucleate and monocyte phagocytizing function, both during and after the hemodialysis session.By means of flow cytometry, we evaluated the capacity for phagosoma formation and oxidative burst both in polymorphonucleates and monocytes. Ten hemodialysis patients were included in the study. Six separate dialysis procedures for each patient were considered, one per dialyzer (3 cellulosic and 3 synthetic membranes). Tests were performed at 15', 60', 210’ and 4 hours after the session end. Comparative evaluation was made according to Student's t test.Polymorphonucleate phagocytosis and oxidative burst activation were globally more marked for synthetic than cellulosic membranes, tending to level out in the post-dialysis. This result could be affected by their functional exhaustion following pulmonary sequestration. Monocyte intradialytic phagocytosis and oxidative burst proved more activated by cellulosic membrane. All differences tended to vanish in the post-dialysis.
- Published
- 1999
- Full Text
- View/download PDF
10. Severe Gastrointestinal Bleeding in a Uremic Patient Treated with Estrogen-Progesterone Therapy
- Author
-
Mosconi, G., Mambelli, E., Zanchelli, F., Isola, E., Perna, C., De Pascalis, A., Raimondi, C., Ventrucci, M, and Stefoni, S.
- Abstract
Gastrointestinal bleeding is a frequent complication in hemodialysis patients; angiodysplasia is a potential cause, with a higher incidence in uremic patients. We describe a case of severe anemia (Hemoglobin up to 3.5 g/dl) secondary to diffuse angiodysplastic lesions in a hemodialysis patient with mixed connective tissue disease. The case is characterised both by the severity of the clinical picture (extension and entity of angiodysplastic lesions, frequency of bleeding episodes) and by the patient's religious faith which made her reject blood transfusions. We underline the efficacy of estrogen-progesterone therapy in view of the modest results obtained with other therapeutic strategies on bleeding.
- Published
- 1999
- Full Text
- View/download PDF
11. Hemoperfusion with a New Anion Exchange Resin Corrects the Metabolic Alkalosis in Pyloric Stenosis: An Experimental Demonstration
- Author
-
Faenza, S., Balestri, M., Martinelli, G., Spighi, M., Fini, M., Giardino, R., Colì, L., Cianciolo, G., Stefoni, S., and Bonomini, V.
- Abstract
An experimental model of hypertrophic pyloric stenosis was made by suture of the pyloric wall and gastrostomy in 10 rabbits under general anesthesia. Blood sampling indicated severe alkalosis and hypochloremia 3h 30 min after surgery. To correct the derangement, we tested an ion exchange resin (Dowex SAR), coated with a methacrylic hydrogel. A cartridge containing 18 g of this resin was inserted in an extracorporeal circuit. This chloride charged resin achieved uptake of HCO−3ions, and elution of CI−ions. The electrolytic balance was fully restored after 10 min of treatment.
- Published
- 1992
- Full Text
- View/download PDF
12. Biocompatibility of Charcoal Hemoperfusion. Effects of Long-Term Treatment on Lymphocyte Characteristics and Function
- Author
-
Stefoni, S., Costa, A. Nanni, D'Arcangelo, G. Liviano, Biavati, M., lannelli, S., and Bonomini, V.
- Abstract
Biocompatibility of charcoal hemoperfusion was studied in a group of 15 uremic patients, evaluating the effects of long-term treatment on some structural and functional parameters of circulating lymphocytes: in vivo distribution of T-cell subsets; surface T3, T4 and T8 antigen expression, in vivo and in vitro DNA synthesis. A comparative analysis was performed with patients on conventional dialysis using cuprophan membranes.
- Published
- 1986
- Full Text
- View/download PDF
13. Hemoperfusion in Reduced-Time Programmes for Chronic Uremia. Long-Term Results
- Author
-
Stefoni, S., Colì, L., Feliciangeli, G., Scolari, M.P., and Bonomini, V.
- Abstract
This paper reports the Authors' 8 year experience in the clinical use of charcoal hemoperfusion as a means to reduce the weekly time of treatment in chronic uremic patients. Two different programmes were applied. Programme A (34 patients) which involved substituting the 3 procedures per week of standard dialysis (4 hours duration each) by 2 procedures of combined hemodialysis and hemoperfusion, again of 4 hours duration each. Programme B (18 patients) which involved substituting the 3 procedures per week of 4 hours duration by 3 procedures of 3 hours each, 2 of combined hemodialysis and hemoperfusion, 1 of conventional dialysis. The net weekly reduction was 33% for Programme A and 25% for Programme B. The efficacy of the two Programmes was evaluated by clinical, hematochemical, nutritional and instrumental parameters.
- Published
- 1986
- Full Text
- View/download PDF
14. Combined Hemodialysis-hemoperfusion Treatment Reduces the time of Substitutive Therapy in Chronic Uremia
- Author
-
Stefoni, S., Feliciangeli, G., Colì, L., Scolari, M.P., and Bonomini, V.
- Abstract
Charcoal hemoperfusion has long been used in chronic uremia as an adjunct or substitute for conventional hemodialysis.In this study a regular combination of hemoperfusion and hemodialysis was used to cut down the weekly substitutive sessions from 3 to 2. Ten RDT patients were treated with the reduced-time schedule for 5–56 weeks. Clinical and metabolic conditions remained stable in all patients and no sign of inadequate treatment appeared. Long-term charcoal hemoperfusion was confirmed to be a safe and risk-free procedure. No change in platelets, white cells, red cells, fibrinogen and other hematochemical parameters were detected.
- Published
- 1981
- Full Text
- View/download PDF
15. Regular Hemoperfusion in Regular Dialysis Treatment. A Long-Term Study
- Author
-
Stefoni, S., Colì, L., Feliciangeli, G., Baldrati, L., and Bonomini, V.
- Abstract
The capacity of activated charcoal to remove toxins from the blood is well established. Its poor biocompatibility, inability to remove urea, electrolytes and water, and high cost have so far been the major objection to a wider use of charcoal with chronic uremic patients.The availability of a charcoal coated by a new highly hydrophilic methacrylate based membrane enabled us to keep 18 uremic patients on a combined hemodialysis-hemoperfusion schedule for 4–52 weeks. Investigations concerned patients in whom relapsing signs of uremia occurred despite technically adequate dialysis, and other cases where dialysis was both technically and clinically adequate. In the first group of patients, the conbined programme led to an improvement of the dialysis resistent clinical signs, while certain positive metabolic effects were also observed. In the second group, the hemodialysis-hemoperfusion treatment allowed a reduction of about 30% in time of treatment per week.Tolerance of the new coated charcoal was good throughout treatment in terms both of biocompatibility and of side effects.
- Published
- 1980
- Full Text
- View/download PDF
16. Evidence of Profiled Hemodialysis Efficacy in the Treatment of Intradialytic Hypotension
- Author
-
Colì, L., La Manna, G., Dalmastri, V., De Pascalis, A., Pace, G., Santese, G., Stefanio, C., Ursino, M., Zacà, F., and Stefoni, S.
- Abstract
In the last 10 years the percentage of dialysis patients suffering from clinical intradialytic intolerance has greatly increased.Profiled hemodialysis (PHD) is a new technical approach, alternative to standard hemodialysis (SHD) for the treatment of intradialytic symptomatic hypotension. It is based on intradialytic modulation of the dialysate sodium concentration, using a dialysate sodium concentration profile elaborated by a new mathematical kinetic model.The aim of PHD is to reduce the intradialytic blood volume decrease, thanks to a dialysate sodium profile, which allows a reduction in the plasma osmolarity decrease, thereby boosting intravascular fluid refilling.This work aims at clinically validating the PHD technique, by testing its ability, against SHD, to maintain a more stable intradialytic blood volume; this evaluation was supported by monitoring some hemodynamic parameters.Twelve dialysis patients on SHD treatment were selected because of their intradialytic symptomatic hypotension. Twelve SHD (one per patient) and 12 PHD sessions (one per patient) were performed to achieve the same sodium mass removal and body weight decrease on both PHD and SHD. During these sessions we monitored the blood volume variation % by the critline (a non invasive blood volume monitoring device), the mean blood pressure and heart rate directly and, finally, the stroke volume and cardiac output indirectly by bidimensional doppler-echocardiography.Comparison of the results obtained with the two techniques shows PHD to achieve a significantly more stable blood volume, blood pressure and cardiovascular function than SHD, in particular during the second and the third hour of the dialysis session.
- Published
- 1998
- Full Text
- View/download PDF
17. An Algorithm for the Rational Choice of Sodium Profile during Hemodialysis
- Author
-
Ursino, M., Colì, L., Dalmastri, V., Volpe, F., La Manna, G., Avanzouni, G., Stefoni, S., and Bonomini, V.
- Abstract
The incidence of intradialytic disequilibrium syndrome and symptomatic hypotension has increased significantly among dialysis patients over the last ten years. Profiled hemodialysis (PHD) is a new technique, based on the intradialytic modulation of dialysate sodium concentration, which aspires to reduce to previous imbalances.This paper presents a new algorithm for the determination of a rational dialysate sodium profile during PHD. A mathematical model of solute kinetics, monocompartmental for sodium and bicompartmental for urea is used. The algorithm allows the sodium profile to be elaborated a priori before each dialysis session, respecting the individual sodium mass removal and weight gain. A procedure allowing the adjustment of the method to the individual characteristics, on the basis of routine measurements performed before each session is also presented.The method was validated during seven dialysis sessions. Comparison between data measured in vivo and those predicted by the model showed standard deviations corresponding to the range of laboratory measurement errors: 1.50 mEq/L for sodium and 0.87 mmol/L for urea. In vivo implementation of PHD by our algorithm allows one to remove an amount of sodium close to that established a priori on the basis of patient's need.
- Published
- 1997
- Full Text
- View/download PDF
18. Effect of Different Dialysis Membranes on Platelet Function. A Tool for Biocompatibility Evaluation
- Author
-
De Sanctis, L.B., Stefoni, S., Cianciolo, G., Colì, L., Buscaroli, A., Feliciangeli, G., Borgnino, L.C., Bonetti, M., Gregorini, M.C., De Giovanni, P., and Buttazzi, R.
- Abstract
Intradialytic coagulative and platelet activation, one of the main consequences of blood-membrane contact, was studied in a group of 5 RDT patients with a comparative evaluation of 3 different dialytic membranes: Cuprophan (CU), Polysulfone (PS) and Cellulose Triacetate (CT). Each patient underwent 5 consecutive dialysis sessions with the above mentioned membranes. Intradialytic platelet activation was studied through a morpho-functional evaluation between the mean platelet volume (MPV) and Serotonin (S), ß-Thromboglobulin (ß-TG) and Platelet Factor 4 (PF4) serum levels. These determinations were made before HD (time 0) and after 30', 120’ and 240'. We also checked the intradialytic status of thrombogenesis and fibrinolysis determining aPTT, thrombin time, fibrinogen, antithrombin III (AT III), α-2 antiplasmin and plasminogen, at the same time intervals. All membranes tested (CU, PS, CT) caused appreciable intradialytic platelet activation, above all after 15’ and at the end of dialysis sessions, more marked for CU than PS or CT. In particular MPV showed a decrease throughout the session (-5% at 30’ and -9% at 240') while S, ßTG and PF4 peripheral blood levels showed a significant increase at the same intervals with CU membrane. Lastly coagulative and fibrinolytic parameters showed no significant differences among any of the membranes tested.
- Published
- 1996
- Full Text
- View/download PDF
19. A Simple Mathematical Model of Intradialytic Sodium Kinetics: “in vivo”Validation During Hemodialysis with Constant or Variable Sodium
- Author
-
Ursino, M., Colì, L., La Manna, G., Cicilioni, M. Grilli, Dalmastri, V., Giudicissi, A., Masotti, P., Avanzolini, G., Stefoni, S., and Bonomini, V.
- Abstract
A simple mathematical model of the intradialytic relationship between natraemia and dialysate sodium concentration is presented. The model includes a bicompartmental description of sodium, urea and fluid kinetics and an algebraic characterization of diffusive/convective mass-transfer across the dialysis membrane. Its ability to provide realistic responses has been validated comparing model predictions by a priori parameter tuning against quantities measured during in vivo sessions with both constant and variable dialysate sodium concentration. A quantitative analysis of model predictions indicates that the mean deviation between data calculated by the model and those measured in vivo is 1.32 mEq/l for sodium and 0.76 mmol/l for urea, values which do not greatly exceed the measurement errors of current instruments. The model's predictive capacity thus proves reliable. The ability of the model to calculate the amount of sodium removed and the time course of intra-extracellular volumes during the dialysis session makes it possible to forecast the patient's clinical tolerance to a given sodium dialysate concentration.
- Published
- 1996
- Full Text
- View/download PDF
20. Strategies in Renal Failure and the Impact of Lipids
- Author
-
Bonomini, V., Scolari, M.P., Mosconi, G., Todeschini, P., Cianciolo, G., and Stefoni, S.
- Abstract
The main points to note in terms of strategies in renal failure and the impact of lipids are: 1) Timing and typing of dyslipidemia; 2) Occurrence of dyslipidemia in the course of strategies (conservative, dialysis and transplantation); 3) How the strategies can handle the impact of lipids. Analysis of point 1 confirms what a complex profile uremic dyslipidemia presents, involving the type, class, composition and enzyme systems involved in lipid metabolism. In conservative and dialysis, type IV (triglycerides) predominates; in transplantation, type II (cholesterol). Examination of point 2 shows the non obligatory relationship between dyslipidemia and the various strategies of treatment. Lipid abnormalities, type IV or II, occur in 50-60% of patients. Uremic factors for dyslipidemia include: 1) enhanced hepatic stimulation or altered removal in conservative strategies; 2) the same causes plus “specific” promotors in dialysis (dialysis fluid, plasticizer leaching; bioincompat-ibility, etc.); 3) steroid therapy and other “accessories” in transplantation. A genetic predisposition is very likely present in all patients. Point 3, finally, analyzes the various “supplements” that each strategy requires to cope with the lipid impact. Generic rules (ranging from doing nothing, to diet, drugs, etc.) are of value in all strategies when dyslipidemia occurs. More specific rules include: a) Conservative strategies: appropriate dietetic optimization and modulation (protein-lipid-carbohydrate ratio in terms of calories); b) Dialysis: timing treatment and improving biocompatibility; c) Transplantation: reducing steroids as much as possible.
- Published
- 1993
- Full Text
- View/download PDF
21. Fibroblast proliferation over dialysis membrane: an experimental model for “tissue” biocompatibility evaluation
- Author
-
Biagini, G., Stefoni, S., Solmi, R., Castaldini, C., Buttazzi, R., Rossetti, A., Belmonte, M. Mattioli, Costa, A. Nanni, Lannelli, S., Borgnino, L.C., and De Sanctis, L.
- Abstract
The present study reports on a biological model based on fibroblast proliferation applied to 3 different types of flat-plate dialysis membrane, in order to ascertain whether the artificial materials currently used in hemodialysis cause in vitro cellular proliferation. The study plan we followed involved plate membrane isolation from non-used dialyzers and used dialyzers, observed through scanning electron microscopy (SEM) both before and after testing with human fibroblasts by means of cell culture. Fibroblast growth was assessed by phase contrast light microscopy examination and cytometric DNA content evaluation. Our investigations proved that the artificial materials we considered interact with fibroblast cultures. Noticeable proliferative response was observed both after contact with unused material and on mediation by the protein layer absorbed on the membrane surface at the end of dialysis sessions. In this last case fibroblast proliferative activity appeared higher than that observed with unused membranes, showing that the soluble molecules entrapped in the protein layer appeared able to exert a biological activity even in in vitro tests
- Published
- 1994
- Full Text
- View/download PDF
22. Mechanical effects of heart pulse propagation on a vessel-graft suture line stress
- Author
-
Selezov, I., Avramenko, O., Fratamico, G., Pallotti, G., Pettazzoni, P., Sanctis, L.B. DE, Coì, L., Stefoni, S., and Bonomini, V.
- Abstract
The effects of vessel joint where the both sides have different wall properties on the heart pulse propagation are investigated. Such a local disturbance can influence post-transplantion pathology and evolution of the organ inconsistence.Using a mathematical model, developed in a previous article, we perform analytical analysis and present some qualitative and quantitative estimations. The effects of jointed vessels with different thicknesses and radii on the local concentration of the pressure, radial wall displacement, bending moment and shear force are analyzed in detail. In particular, it is obtained that the bending and shear stresses at a joint sharply and strongly increase in comparison with the uniform vessel ones. (Int J Artif Organs 1998; 21: 114–8)
- Published
- 1998
- Full Text
- View/download PDF
23. The First Case of Ureteral Duplication in a Combined Liver-Kidney Transplantation
- Author
-
Nardo, B., Montalti, R., Pacilè, V., Bertelli, R., Beltempo, P., Cavallari, G., Puviani, L., Licursi, M., Stefoni, S., Cavallari, A., and Faenza, A.
- Abstract
Aim Kidney transplantation with ureteral duplication may represent a doubled risk factor in terms of ureteral stenosis or necrosis with urinary leakage usually from the site of ureteroneocystostomy. The incidence of complete duplication is very low at 0.19%. We report a kidney with ureteral duplication in the specific setting of multiorgan transplantation since it could be considered a adjunctive risk factor for urological complications.Methods The recipient was a 67-year old man, suffering from terminal renal insufficiency. He was also affected by HCV-related cirrhosis. The patient had been waiting for the combined transplantation for 27 months and in the last two months his hepatic function dramatically worsened. The donor was a 53-year old man who died of non-traumatic subarachnoid hemorrhage. Good HLA compatibility was observed between donor and recipient. During harvest both kidneys presented a complete ureteral duplication. So the ureters were freed together with a wide cuff of periureteral tissue and dissected distally. No vascular abnormalities were noted during the removal of either kidney. The grafts were flushed with University of Wisconsin solution and stored in the same solution.Results The liver was reperfused after 9 hours of cold ischemia. Subsequently the kidney was vascularized after 15 hours of cold ischemia. Urine production occurred immediately after revascularization. Two separated ureteroneocystostomies with a single antireflux technique were performed. Cyclosporine and steroids were given. Post-operative course was uneventful and liver and kidney function were normal. The 7-day cystography was normal. The 6, 12, 24 month ultrasonographies showed no signs of hydronephrosis or hydroureter. After 28 months renal cancer was diagnosed and the patient underwent a right nephrectomy. The liver-kidney recipient had excellent hepatic and renal function for 84.7 months. He died of malignancy from de novo tumor.Conclusions On the basis of this experience, a kidney with an ureteral duplication, while rare, can be satisfactorily used also in combined liver-kidney transplantation.
- Published
- 2006
- Full Text
- View/download PDF
24. Immunosuppression in Renal Transplantation
- Author
-
Bonomini, V., Scolari, M.P., Buscaroli, A., D'arcangelo, G. Liviano, and Stefoni, S.
- Published
- 1997
- Full Text
- View/download PDF
25. Is Ace Inhibitor Treatment a Possible Cause of Better Cardiovascular Remodelling in Well Functioning Kidney Transplant?
- Author
-
LA Manna, G., Campieri, C., Dalmastri, V., Buscaroli, A., Tarquinii, M., Giudicissi, A., Neri, L, Pace, G., Mosconi, G., Scolari, M.P., Stefoni, S., and Bonomini, V.
- Abstract
Diseases of the cardiovascular system are a common cause of death in renal transplanted patients. In this study we assessed the echocardiographic morphological and functional findings after renal transplantation of two homogenous groups of transplanted patients with normal renal function. The first (A) with spontaneously normotensive patients, the second (B) with moderate hypertension treated mainly with Ace inhibitors. Analysis of these data highlights two noteworthy results: the similar left ventricle hypertrophy found in both groups and the existence of better diastolic compliance among the hypertensive transplanted patients. If this is confirmed by studies currently in progress, the importance of Ace-inhibitors treatment in remodelling cardiac dysfunction after long term dialysis treatment might be seriously considered.
- Published
- 1995
- Full Text
- View/download PDF
26. Double Kidney Transplantation: Initial Experience of the Bologna Transplant Center
- Author
-
Nardo, B., Pacilè, V., Bertelli, R., Beltempo, P., Montalti, R., Puviani, L., Neri, F., Mosconi, G., Scolari, M.P., Liviano D'Arcangelo, G., Stefoni, S., and Faenza, A.
- Abstract
Aim Double-kidney transplantation is performed using organs from marginal donors with a histological score not suitable for single kidney transplantation. The aim of the study is to verify the results obtained with double-kidney transplantation in terms of graft and patient survival and complications.Methods Between September 2001 and September 2004, 16 double-kidney transplantations were performed in our center. The kidneys were all perfused with Celsior solution and the mean cold ischemia time was 17.6 ± 2.7 hours. In all cases a pre-transplant kidney biopsy was performed to evaluate the damage. Immunosuppression was tacrolimus based for all patients.Results Eight patients had good renal postoperative function while the other eight had acute tubular necrosis. Two of the patients who had severe acute tubular necrosis never recovered renal function. There was only one episode of acute rejection, while the incidence of urinary complications was 31.2%; there were two surgical revisions for intestinal perforation. The graft and recipient survival was 78.1% and 100% and 78.1% and 93.7% at 3 and 36 months.Conclusions Double-kidney transplantation is a safe way to face the organ shortage. Moreover the score used in this study is useful to determine whether a kidney should be refused or suitable for single or dual-kidney transplantation. The results of our initial experience are encouraging, but this series is too small in number to consent a conclusive statement.
- Published
- 2006
- Full Text
- View/download PDF
27. Welcome Address
- Author
-
Buscaroli, A. and Stefoni, S.
- Published
- 2005
- Full Text
- View/download PDF
28. Incidence and prevalence of cancer in kidney transplantation waiting list patients: an Italian experience.
- Author
-
Mosconi G, Centofanti F, Capelli I, Ricci A, Persici E, Gandolfini I, Rubbiani E, Buzio C, Cappelli G, Costa AN, and Stefoni S
- Subjects
- Adolescent, Adult, Aged, Female, Humans, Incidence, Italy epidemiology, Kidney Failure, Chronic epidemiology, Male, Middle Aged, Neoplasms diagnosis, Prevalence, Retrospective Studies, Time Factors, Young Adult, Kidney Failure, Chronic surgery, Kidney Transplantation, Neoplasms epidemiology, Waiting Lists
- Abstract
Introduction: Evaluation of kidney transplant candidates is based on strict exclusion of major pathologies, such as neoplastic disease. The aim of this study is to evaluate epidemiological and clinical impact of tumor disease in an Italian renal transplant waiting list and to propose a screening schedule for neoplastic detection. , Materials and Methods: We retrospectively observed data of patients enrolled on the Emilia-Romagna kidney transplant waiting list between 1st August 2008 and 31st December 2010, evaluating the different causes of getting out from the list, the histologic type and incidence of cancer and the correlation between cancer onset and clinical features. The ratio of observed to expected cancer numbers (standardized incidence ratio, SIR), was estimated., Results: We observed 2345 patients; 1297 got out from the waiting list; 57 of them (4,4%) got out because the onset of tumor. The overall incidence rate of cancer was 1354.8 (x 100,000 person-year) (1045.9 person-year in patients awaiting for first transplant(FT), 1851.5 person-year in patients awaiting for second transplant(ST)). The overall prevalence of cancer was 2,43% (2.2% in FT, 3.4% in ST) with a SIR of 1.8; In our population the prevalence of cancers related to ESKD was 52.6% with a SIR of 15.8. , Conclusion: Kidney transplant waiting list patients present a higher incidence and prevalence of cancer compared to general population; it could be important to evaluate them for ESKD related malignancies because of their high incidence.
- Published
- 2013
- Full Text
- View/download PDF
29. Role of the hemodialysis vascular access type in inflammation status and monocyte activation.
- Author
-
Colì L, Donati G, Cappuccilli ML, Cianciolo G, Comai G, Cuna V, Carretta E, La Manna G, and Stefoni S
- Subjects
- Aged, Aged, 80 and over, Analysis of Variance, Biomarkers blood, Catheterization, Central Venous instrumentation, Cellular Senescence, Chi-Square Distribution, Female, Humans, Hyaluronan Receptors blood, Inflammation Mediators blood, Interleukin-6 blood, Italy, Lipopolysaccharide Receptors blood, Male, Middle Aged, Phenotype, Receptors, IgG blood, Risk Assessment, Risk Factors, Serum Albumin analysis, Tumor Necrosis Factor-alpha blood, Arteriovenous Shunt, Surgical adverse effects, Catheterization, Central Venous adverse effects, Catheters, Indwelling adverse effects, Inflammation immunology, Monocytes immunology, Renal Dialysis adverse effects
- Abstract
Purpose: The aim of this study was to ascertain the role of different vascular access types in inflammatory status, monocyte activation, and senescence in hemodialysis patients., Methods: We recruited 126 hemodialysis patients, including 51 with arterovenous fistula (AVF), 32 with arterovenous graft (AVG), and 43 with tunneled cuffed catheters (TCC). In dialysis patients enrolled in the study and in a control group of 40 healthy subjects, we measured the serum levels of albumin, CRP, IL-6, and TNF-a, the expression of CD14, CD44, and CD32 on monocyte surface, and the percentage of monocytes exhibiting a senescent phenotype (CD14+CD32+)., Results: The patients with AVG compared to those with AVF had: a) higher levels of CRP and TNF-a; b) increased expression of CD14 and CD32 on monocyte surface, with no difference in CD44 expression; c) no difference in the percentage of CD14+CD32+ monocytes. In the comparison of TCC vs. AVF group, we observed significantly higher values of: a) circulating inflammatory markers (CRP, IL-6, TNF-a); b) monocyte surface expression of cellular activation markers (CD14, CD44 and CD32); c) relative count of CD14+CD32+ monocytes. When comparing TCC vs. AVG group, we found: a) no difference in serum levels of CRP, IL-6, and TNF-a; b) no difference in the expression of CD14, CD44, and CD32 on monocyte surface; c) no difference in the percentage of CD14+CD32+ monocytes., Conclusions: These results suggest that the use of AVG and TCC for dialysis vascular access is associated with serological and cellular indexes of inflammatory reaction, also resulting in a higher degree of monocyte activation and senescence.
- Published
- 2011
- Full Text
- View/download PDF
30. A simple mathematical model of intradialytic sodium kinetics: "in vivo" validation during hemodialysis with constant or variable sodium.
- Author
-
Ursino M, Colì L, La Manna G, Grilli Cicilioni M, Dalmastri V, Giudicissi A, Masotti P, Avanzolini G, Stefoni S, and Bonomini V
- Subjects
- Adult, Aged, Cellulose chemistry, Cellulose metabolism, Dialysis Solutions metabolism, Female, Humans, Male, Middle Aged, Models, Theoretical, Sodium metabolism, Urea pharmacokinetics, Uremia therapy, Cellulose analogs & derivatives, Dialysis Solutions chemistry, Membranes, Artificial, Renal Dialysis, Sodium pharmacokinetics
- Abstract
A simple mathematical model of the intradialytic relationship between natraemia and dialysate sodium concentration is presented. The model includes a bicompartmental description of sodium, urea and fluid kinetics and an algebraic characterization of diffusive/convective mass-transfer across the dialysis membrane. Its ability to provide realistic responses has been validated comparing model predictions by a priori parameter tuning against quantities measured during in vivo sessions with both constant and variable dialysate sodium concentration. A quantitative analysis of model predictions indicates that the mean deviation between data calculated by the model and those measured in vivo is 1.32 mEq/l for sodium and 0.76 mmol/l for urea, values which do not greatly exceed the measurement errors of current instruments. The model's predictive capacity thus proves reliable. The ability of the model to calculate the amount of sodium removed and the time course of intra-extracellular volumes during the dialysis session makes it possible to forecast the patient's clinical tolerance to a given sodium dialysate concentration.
- Published
- 1996
31. Treatment of uremic patients with biofiltration: efficacy, biocompatibility and medium-term results.
- Author
-
Stefoni S, Colì L, Feliciangeli G, Scolari MP, Liviano D'Arcangelo G, Stagni B, and Bonomini V
- Subjects
- Acid-Base Equilibrium, Acrylic Resins, Adult, Bicarbonates administration & dosage, Biocompatible Materials, Female, Humans, Lymphocyte Activation, Male, Membranes, Artificial, Middle Aged, Renal Dialysis, T-Lymphocytes immunology, Blood, Ultrafiltration methods, Uremia therapy
- Abstract
The present report deals with a medium-term programme using biofiltration on a group of 10 patients, who underwent a regular reduced-time schedule (3 procedures per week, 3 hours duration each) lasting up to 12 months. A polyacrylonitrile AN 69 S membrane was used together with a substitution fluid containing Na and bicarbonate. Hematochemical and nutritional parameters were regularly checked to evaluate the efficacy of treatment. Biocompatibility of materials was evaluated by humoral and cellular immunological tests.
- Published
- 1986
32. Evaluation of a new coated charcoal for hemoperfusion in uremia.
- Author
-
Stefoni S, Feliciangeli G, Coli L, and Bonomini V
- Subjects
- Charcoal, Evaluation Studies as Topic, Humans, Polymethacrylic Acids, Renal Dialysis, Biocompatible Materials therapeutic use, Hemoperfusion instrumentation, Uremia therapy
- Abstract
A new coated charcoal for hemoperfusion in uremia was investigated in 14 patients with end stage renal disease who underwent hemoperfusion or combined hemodialysis-hemoperfusion (39 seances). Investigations concerned removal of small molecules, coagulation and hematological status and amino acids and some hormones equilibrium. Clinical observations were also made in all patients. The methacrylate-coated charcoal enabled the removal of "toxins" up to 5000 daltons and the total solute removal did not significantly differ from previous hemoperfusion systems. However, the new coating membrane showed improved biocompatibility, in terms of clinical side effects and/or platelet and fibrinogen alterations.
- Published
- 1979
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.