A Novel Formulation of Glucose-Sparing Peritoneal Dialysis Solutions with l-Carnitine Improves Biocompatibility on Human Mesothelial Cells

The main reason why peritoneal dialysis (PD) still has limited use in the management of patients with end-stage renal disease (ESRD) lies in the fact that the currently used glucose-based PD solutions are not completely biocompatible and determine, over time, the degeneration of the peritoneal membrane (PM) and consequent loss of ultrafiltration (UF). Here we evaluated the biocompatibility of a novel formulation of dialytic solutions, in which a substantial amount of glucose is replaced by two osmometabolic agents, xylitol and l-carnitine. The effect of this novel formulation on cell viability, the integrity of the mesothelial barrier and secretion of pro-inflammatory cytokines was evaluated on human mesothelial cells grown on cell culture inserts and exposed to the PD solution only at the apical side, mimicking the condition of a PD dwell. The results were compared to those obtained after exposure to a panel of dialytic solutions commonly used in clinical practice. We report here compelling evidence that this novel formulation shows better performance in terms of higher cell viability, better preservation of the integrity of the mesothelial layer and reduced release of pro-inflammatory cytokines. This new formulation could represent a step forward towards obtaining PD solutions with high biocompatibility.     

Association between patient psychosocial characteristics and receipt of in‐center nocturnal hemodialysis among prevalent dialysis patients

Introduction: Compared to traditional in‐center hemodialysis (HD), in‐center nocturnal dialysis (INHD) is characterized by longer sessions and nighttime administration, which may lead to better outcomes for some patients. Given the importance of patient choice in the decision to initiate INHD, we explored associations between patients’ psychosocial characteristics and their receipt of INHD. Methods: Among hemodialysis patients at a medium‐sized dialysis organization, we identified INHD patients as those for whom ≥80% of dialysis sessions were INHD sessions—starting at 6:30 pm or later and lasting ≥5 hours—over the 3 months (≥20 sessions total) after their first INHD session. We extracted dialysis session data from electronic medical records and psychosocial data from social worker assessments. We tested associations of patients’ psychosocial characteristics—as well as demographic and clinical characteristics—with INHD receipt among all hemodialysis patients (INHD and HD) in bivariate analyses and multivariable logistic regression models. Findings: Among 759 patients with complete data, we identified 47 (6.2%) as INHD patients. On average, these patients were more likely than HD patients to be employed (full‐time 10.6% vs. 5.2%; part‐time 17.0% vs. 4.2%; P < 0.001), and they were significantly less likely to require ambulatory assistance (14.9% vs. 39.6%, P < 0.001). In multivariable regressions, we found that part‐time employment (versus being unemployed) was associated with a 7.1 percentage‐point higher likelihood of being an INHD patient (P = 0.01), and the negative association with ambulatory assistance needs approached statistical significance (P = 0.056). No other psychosocial factors included in this main regression analysis were statistically significantly associated with INHD patient status. Discussion: Researchers comparing the outcomes of patients undergoing INHD versus other treatment modalities will need to account for differences in employment status—and other factors like requiring ambulatory assistance and age which may predict the ability to work—between INHD users and comparison patients to avoid bias in estimates.     

Branched Polyvinyl Alcohol Hybrid Membrane for Acid Recovery via Diffusion Dialysis

A branched polymer was prepared by grafting allyltrimethylammonium chloride onto polyvinyl alcohol (PVA) via free‐radical polymerization. Afterwards, a series of hybrid membranes were prepared by sol‐gel cross‐linking between quaternary ammonium‐PVA and tetraethoxysilane. The obtained membranes were characterized in terms of infrared spectroscopy, ion exchange capacity, water uptake, linear expansion ratio, and acid resistance. The thermal properties of the membranes were investigated as well. The diffusion dialysis performances of the membranes were tested by using a simulated feed solution containing HCl and FeCl₂. The diffusion dialysis coefficients and the separation factors were much better than those of the commercial DF‐120 membrane.     

Astragalus membranaceus Inhibits Peritoneal Fibrosis via Monocyte Chemoattractant Protein (MCP)-1 and the Transforming Growth Factor-β1 (TGF-β1) Pathway in Rats Submitted to Peritoneal Dialysis

Inflammation and transforming growth factor-β1 (TGF-β1) contribute to the development of peritoneal fibrosis (PF), which is associated with peritoneal dialysis (PD). Astragalus membranaceus (Astragalus) has anti-inflammatory and anti-fibrotic effects in many diseases. The goal of this study was to determine the anti-fibrotic effects of Astragalus on the PF response to PD. A rat model of PD was induced using standard PD fluid, and PF was verified by HE and Masson’s staining, as well as through the expression of fibroblast surface protein (FSP) and collagen III. The expression levels of monocyte chemoattractant protein (MCP)-1, F4/80 (macrophage/monocyte marker in rat), TGF-β1 and the downstream proteins phospho-SMAD 2/3 in dialyzed peritoneal tissue treated with or without Astragalus was evaluated using immunohistochemistry analysis. Overall correlations between MCP-1 and TGF-β1 staining were analyzed using both the Spearman and Pearson methods. The results showed that Astragalus could inhibit the recruitment and activation of monocytes/macrophages, thereby reducing the production of TGF-β1 in the dialyzed peritoneal membrane. PF was also significantly decreased following treatment with Astragalus. MCP-1 expression had a strong positive correlation with TGF-β1 sensitivity, suggesting that the anti-fibrotic function of Astragalus was mediated by MCP-1 and the TGF-β1 pathway. Our results indicate that Astragalus could be a useful agent against PD-induced PF.     

Water Quality for Renal Dialysis

Over 100000 renal failure patients are treated by dialysis in the European Community (EC), and the number is rapidly increasing due to better medical care. The full importance of the quality of water used for renal dialysis is only now being recognized. Aluminium intoxication, first described in the early 1970s, highlighted the need for adequate treatment of water used to prepare dialysate. Other materials harmful to dialysis patients, such as chloramines, may arise as a result of water treatment practice. The paper presents a European-wide assessment of the problems of trace contaminants in dialysis feed water, and examines some contaminant sources in mains water in the light of dialysis water standards and the current treatment techniques available.     

扩散渗析回收含铜退镀液中的硝酸

采用扩散渗析法回收含铜退镀液中的HNO3,考察流量、流量比、温度等因素对硝酸的回收率、回收液中硝酸浓度以及铜和镍离子截留率的影响.将单级扩散渗析仪改装成新的三级扩散渗析仪,考察了三级逆流扩散渗析对实验结果的影响.单级扩散渗析的结果表明,最佳条件:水/料的流比为1∶1、流量90 mL/h、温度19℃,其硝酸回收率为86.95％、回收浓度6.04 mol/L、Cu2+和Ni2+的截留率分别为90.19％、92.71％.相对于单级扩散渗析,自行改装的三级扩散渗析过程能达到更高回收酸浓度和单位时间内处理更多的料液.在含铜退镀液体系下,利用国产扩散膜实现了扩散渗析对于H+和金属离子具有良好的分离,同时达到了回收硝酸浓度高于原退镀液的效果.