Geometria dell’anello di distribuzione e materiale utilizzato

La qualità chimica e microbiologica delle acque di dialisi è un requisito fondamentale per la biocompatibilità del trattamento emodialitico. Numerosi lavori in letteratura mostrano infatti come la composizione del liquido di dialisi rappresenti uno dei fattori responsabili dello stato microinfiammatorio cronico del paziente emodializzato con importanti conseguenze cliniche Al fine di garantire al paziente un trattamento dialitico con elevati standard di qualità e sicurezza si dovrebbe giungere oggi alla produzione di un dialisato che si definisce ultrapuro (carica batterica <0.1 UFC/ml e concentrazione endotossinica <0.03 UI/ml). Questo ha particolare importanza nelle metodiche “on-line” che consentono l’autoproduzione del liquido di sostituzione durante i trattamenti convettivi

Accuracy of eight-polar bioelectrical impedance analysis for the assessment of total and appendicular body composition in peritoneal dialysis patients

Objective: To establish the accuracy of bioelectrical impedance analysis (BIA) for the assessment of total and appendicular body composition in peritoneal dialysis (PD) patients. Design: Cross-sectional study. Setting: University Nephrology Clinic. Subjects: In all, 20 PD patients and 77 healthy controls matched for gender, age and body mass index. Methods: Whole-body fat-free mass (FFM) and appendicular lean tissue mass (LTM) were measured by dual-energy X-ray absorptiometry. Resistance ( R) of arms, trunk and legs was measured by eight-polar BIA at frequencies of 5, 50, 250 and 500 kHz. Whole-body resistance was calculated as the sum of R of arms, trunk and legs. The resistance index ( RI) was calculated as the ratio between squared height and whole-body or segmental R. Results: RI at 500 kHz was the best predictor of FFM, LTMarm and LTMleg in both PD patients and controls. Equations developed on controls overestimated FFM and LTMarm and underestimated LTMleg when applied to PD patients. Specific equations were thus developed for PD patients. Using these equations, the percent root mean-squared errors of the estimate for PD patients vs controls were 5 vs 6% for FFM, 8 vs 8% for LTMarm and 7 vs 8% for LTMleg. Conclusion: Eight-polar BIA offers accurate estimates of total and appendicular body composition in PD patients, provided that population-specific equations are used

Lipoprotein glomerulopathy treated with LDL-apheresis (Heparin-induced Extracorporeal Lipoprotein Precipitation system): a case report.

INTRODUCTION: Lipoprotein glomerulopathy is a glomerulonephritis which was described for the first time by Saito in 1989 and is currently acknowledged as a separate nosological entity. It is histologically characterized by a marked dilatation of the glomerular capillaries and the presence of lipoprotein thrombi in the glomerular lumens. The dyslipidemic profile is similar to that of type III dyslipoproteinemia with Apolipoprotein E values that are often high; proteinuria and renal dysfunction are present. Proteinuria often does not respond to steroid and cytostatic treatments. The phenotypic expression of lipoprotein glomerulopathy is most probably correlated to a genetic alteration of the lipoprotein metabolism (mutation of the Apolipoprotein E coding gene). In literature, lipoprotein glomerulopathies have mainly been reported in Japanese and Chinese subjects, except for three cases in the Caucasian race, reported in France and the USA.CASE PRESENTATION: We describe the case of a 60-year-old female, Caucasian patient suffering from lipoprotein glomerulopathy, carrier of a new mutation on the Apolipoprotein E gene (Apolipoprotein E(MODENA)), and treated successfully with low density lipoprotein-apheresis with the Heparin induced extracorporeal lipoprotein precipitation system. After a first phase of therapeutic protocol with statins, the patient was admitted for nephrotic syndrome, renal failure and hypertension. Since conventional treatment alone was not able to control dyslipidemia, aphaeretic treatment with heparin-induced Extracorporeal Lipoprotein Precipitation - apheresis (HELP-apheresis) was started to maintain angiotensin converting enzyme inhibitor therapy for the treatment of hypertension. Treatment with HELP-apheresis led to a complete remission of the proteinuria in a very short time (four months), as well as control of hypercholesterolemia and renal function recovery.CONCLUSION: According to this case of lipoprotein glomerulopathy, we believe that renal damage expressed by proteinuria correlates to the levels of lipids and, furthermore, the treatment with HELP-apheresis, by lowering low-density lipoprotein cholesterol and triglycerides, may be considered as a therapeutic option in synergy with pharmacological treatment in the treatment of lipoprotein glomerulopathy

Plasma exchange in acute and chronic hyperviscosity syndrome: a rheological approach and guidelines study

Therapeutic plasma exchange is an extra-corporeal technique able to remove from blood macromolecules and/or replace deficient plasma factors. It is the treatment of choice in hyperviscosity syndrome, due to the presence of quantitatively or qualitatively abnormal plasma proteins such as paraproteins. In spite of a general consensus on the indications to therapeutic plasma exchange in hyperviscosity syndrome, data or guide lines about the criteria to plan the treatment are still lacking. We studied the rheological effect of plasma exchange in 20 patients with plasma hyperviscosity aiming to give data useful for a rational planning of the treatment. Moreover, we verified the clinical applicability of the estimation of plasma viscosity by means of Kawai's equation. Plasma exchange decreases plasma viscosity about 20-30% for session. Only one session is required to normalize plasma viscosity when it is 2.2 till to 6 mPas. A fourth session is useless, especially if the inter-session interval is < 15 days. By means of a polynomial equation, knowing basal-plasma viscosity and the disease of a patient, we can calculate the decrease of viscosity obtainable by each session of plasma exchange then the number of session required to normalize the viscosity. Kawai's equation is able to evaluate plasma viscosity in healthy volunteers, but it is not clinically reliable in paraproteinemias. [Pubmed] [Scholar] [EndNote] [BibTex

Traction forces at the cytokinetic ring regulate cell division and polyploidy in the migrating zebrafish epicardium

Epithelial repair and regeneration are driven by collective cell migration and division. Both cellular functions involve tightly controlled mechanical events, but how physical forces regulate cell division in migrating epithelia is largely unknown. Here we show that cells dividing in the migrating zebrafish epicardium exert large cell–extracellular matrix (ECM) forces during cytokinesis. These forces point towards the division axis and are exerted through focal adhesions that connect the cytokinetic ring to the underlying ECM. When subjected to high loading rates, these cytokinetic focal adhesions prevent closure of the contractile ring, leading to multi-nucleation through cytokinetic failure. By combining a clutch model with experiments on substrates of different rigidity, ECM composition and ligand density, we show that failed cytokinesis is triggered by adhesion reinforcement downstream of increased myosin density. The mechanical interaction between the cytokinetic ring and the ECM thus provides a mechanism for the regulation of cell division and polyploidy that may have implications in regeneration and cancer

A mechanically active heterotypic E-cadherin/N-cadherin adhesion enables fibroblasts to drive cancer cell invasion

Cancer-associated fibroblasts (CAFs) promote tumour invasion and metastasis. We show that CAFs exert a physical force on cancer cells that enables their collective invasion. Force transmission is mediated by a heterophilic adhesion involving N-cadherin at the CAF membrane and E-cadherin at the cancer cell membrane. This adhesion is mechanically active; when subjected to force it triggers β-catenin recruitment and adhesion reinforcement dependent on α-catenin/vinculin interaction. Impairment of E-cadherin/N-cadherin adhesion abrogates the ability of CAFs to guide collective cell migration and blocks cancer cell invasion. N-cadherin also mediates repolarization of the CAFs away from the cancer cells. In parallel, nectins and afadin are recruited to the cancer cell/CAF interface and CAF repolarization is afadin dependent. Heterotypic junctions between CAFs and cancer cells are observed in patient-derived material. Together, our findings show that a mechanically active heterophilic adhesion between CAFs and cancer cells enables cooperative tumour invasion

Once-weekly epoetin-beta in renal anemia: the clinical evidence

No abstract available

Le alterazioni del volume e della composizione elettrolitica dei liquidi corporei.

Le alterazioni del volume e della composizione dei liquidi corporei sono manifestazioni frequenti di numerose malattie ed il loro rapido riconoscimento e trattamento diventa essenziale per ripristinare il normale stato di salute. Il bilancio corporeo dei liquidi, variabile dalla grave iperidratazione (anasarca) alla disidratazione, è strettamente collegato al contenuto elettrolitico corporeo; dalla loro interazione dipende la distribuzione dei fluidi tra i diversi compartimenti, l'osmolalità dell'extra e dell'intracellulare, e la funzione metabolica cellulare

Clinical Experience with PMMA Membrane

No abstract available