The Relationship Between Serum Folate Level and Residual Renal Function in CAPD Patients.

Objective: To investigate the relationship between serum folate (FA) levels and residual renal function (RRF) in continuous ambulatory peritoneal dialysis (CAPD) patients. Methods: Clinical data were collected from 180 hospitalized patients who received CAPD regularly. Patients were divided into the FA deficiency group and the FA non-deficiency group according to serum FA level. Data on age, sex, PD vintage, hemoglobin, mean corpuscular volume, serum FA, total Kt/V, residual kidney Kt/V, peritoneum Kt/V, creatinine clearance (Ccr), ultrafiltration volume, cystatin C (cytC), serum creatinine (Scr), urea nitrogen, retinol-binding protein and the primary disease were gathered from 2 groups. Statistical methods were used to analyze the relationship between serum FA level and RRF. Results: Peritoneal Kt/V, cytC, Scr were higher, and residual kidney Kt/V was lower in FA deficiency group than in non-deficiency group. Univariate correlation showed the peritoneal Kt/V, cytC, Scr negatively correlated with serum FA while residual kidney Kt/V positively correlated with serum FA, and there was a simple linear regression relationship between serum FA and residual kidney Kt/V. Differences were statistically significant (P<0.05). Conclusion: There is a relationship between serum FA and RRF in CAPD patients. Prospective studies or trials should be performed to clarify the importance of FA supplementation on RRF during peritoneal dialysis.

Effects of Zinc Smelting Waste Slag Treated with Root Organic Acids on the Liver of Zebrafish (Danio rerio).

Vegetation reconstruction was widely adopted for the waste slag site. But the toxic elements may be made public from slag due to the organic acid secreted by plant roots, which will pollute the surrounding environment and harm human health. The purpose of the study was to evaluate the harm of toxic substances released from zinc (Zn) smelting waste slag to zebrafish. The effect was simulated by adding organic acid to slag, and the toxicity of the slag was evaluated through the enzyme activity, genetic toxicity, tissue sections of zebrafish liver tissue. The results showed that more heavy metals were made public from the slag, as the concentration of organic acids increased. Exposure to toxic substances for 14 days, the antioxidant enzyme activities, termed as superoxide dismutase (SOD) and catalase (CAT), were significantly affected, which caused obvious malondialdehyde (MDA) accumulation. A comet assay revealed dose-dependent DNA damage in hepatocytes. Depending on the histopathological analysis, atrophy and necrosis of cells and increased hepatic plate gap were observed. The obtained results highlighted that toxic substances from slag may be deleterious to zebrafish.

Evidence for Chronic Kidney Disease-Mineral and Bone Disorder Associated With Metabolic Pathway Changes.

Abnormalities in the levels of calcium, phosphorus, and parathyroid hormone (PTH) in serum are typical for patients with chronic kidney disease (CKD). They are used routinely to predict the onset of CKD-mineral and bone disorder (MBD). However, CKD-MBD associated with metabolic pathway imbalance is not well understood.The objective of the study was to identify endogenous metabolic signatures in patients with intact PTH using mass spectrometry-based metabolomics. This study was a cross-sectional study. Ultra performance liquid chromatography-Quadrupole Time-of-Flight/mass spectrometry-based metabolic profiling was employed to analyze serum samples from 19 disease controls (DCs) (intact parathyroid hormone [iPTH] 150-300 pg/mL) and 19 secondary hyperparathyroidism (SHPT) patients (iPTH >300 pg/mL) (the training data set) to identify metabolic biomarkers for CKD-MBD. Then, another set of samples including 19 DCs (iPTH 150-300 pg/mL) and 19 SHPT patients (iPTH >300 pg/mL) (the test data set) were used to validate the potential biomarkers identified.Metabolic profiling analyses revealed different patterns of endogenous metabolites between the SHPT and the DC groups. A total of 32 unique metabolites were identified and 30 metabolites were elevated in the iPTH compared with control serum pools. Cytidine and L-phenylalanine were downregulated in the SHPT patients. The metabolic signatures identified were assessed respectively by an internal 10-fold cross validation with an accuracy of 91.4% and an external validation with an accuracy of 71.1%, a sensitivity of 73.7%, and a specificity of 68.4%.Mass spectrometry-based metabolomic analyses for SHPT patients promises immense potential for early diagnosis and therapy monitoring. Our results indicated that the onset of CKD-MBD is associated with pathway changes of protein synthesis and metabolism, amino acid metabolism, energy metabolism, and steroid hormone metabolism, with obvious promise for better understanding the pathogenesis of this disease. Several metabolic biomarkers were identified, which warrant further development.

Predictors of poor sleep quality and excessive daytime sleepiness in peritoneal dialysis patients.

To explore the possible impact factors on daytime sleepiness among peritoneal patients from a single center in China. A cross-sectional study was conducted in 98 prevalent peritoneal dialysis (PD) patients using both the Pittsburgh Sleep Quality Index (PSQI) questionnaire of sleep quality and the Epworth Sleepiness Scale (ESS) questionnaire of excessive daytime sleepiness (EDS). Biochemical differences between daytime sleepiness and non-daytime sleepiness population were evaluated, following univariate and multivariable analysis to find the risk factors on sleep disturbance. The prevalence of "poor sleep quality" (PSQI > 5) was 74.49%, while daytime sleepiness (ESS ≥ 9) occurred in 22.45%. Mean PSQI was 9.06 ± 4.60 and EES was 6.31 ± 4.98. Compared to non-EDS cases, patients with ESS ≥ 9 had worse residual renal function (RRF), higher serum creatinine, higher serum magnesium and elevated serum ferritin. In univariate analysis, ESS correlated with serum albumin (r = 0.346, p = 0.015), phosphate (r = 0.313, p = 0.029), magnesium (r = 0.376, p = 0.008) and urinary Kt/V (r = -0.341, p = 0.029). Finally, multivariable linear regression indicated that urinary Kt/V, PSQI and magnesium were independent predictors of ESS score. EDS does exist in PD patients and is associated both with poor nighttime sleep quality and lower RRF. Hypermagnesemia may be a treatable risk factor to improve daytime tiredness.