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Objective:To explore the relationship between low serum albumin levels and its duration on first episode of peritonitis in peritoneal dialysis (PD) patients.Methods:PD patients who were regularly followed up in the Pearl River Delta region from September 1, 2000 to July 6, 2021 in Shunde Hospital of Southern Medical University, Nanfang Hospital of Southern Medical University, and Foshan First People′s Hospital were retrospectively selected. The patients were divided into low serum albumin group (LSA group, mean albumin<35 g/L), moderate serum albumin group (MSA group, 35 g/L≤mean albumin<40 g/L) and high serum albumin group (HSA group, mean albumin≥40 g/L) according to the mean albumin of the patients, and the differences among the three groups were compared. The Kaplan-Meier survival analysis method was used to compare the risk of peritonitis events in different mean albumin groups and different durations of hypoalbuminemia. The multivariate Cox regression model was used to analyze the relationship between serum albumin levels and duration of hypoalbuminemia and new-onset peritonitis.Results:A total of 1 853 PD patients were included in this study, aged (49.72±15.34) years, and 1 036(55.9%) males. There were 551 patients (29.7%) in the LSA group, 920 patients (49.7%) in the MSA group, and 382 patients (20.6%) in the HSA group. The median follow-up was 37 (15, 66) months and there were 508 patients (27.4%) with new-onset peritonitis during the follow-up. Compared with the LSA group, the incidence of new peritonitis in the MSA group and HSA group was lower ( χ2=14.053, P<0.001; χ2=21.857, P<0.001), but there was no significant difference in the incidence of new peritonitis between the HSA group and MSA group. The Kaplan-Meier survival analysis showed that the cumulative incidence of peritonitis in the LSA group was significantly higher than that in the MSA group and HSA group (Log-rank χ2=22.128, P<0.001). Compared with PD patients with normal serum albumin, the patients with longer duration of hypoalbuminemia tended to have a higher incidence of new peritonitis. Multivariate Cox regression analysis showed that the mean albumin<35 g/L (LSA group/MSA group, HR=1.495, 95% CI 1.198-1.866, P<0.001; LSA group/HSA group, HR=1.459, 95% CI 1.104-1.928, P=0.008) was an independent risk factor of new-onset peritonitis in PD patients and the prolongation of duration of hypoalbuminemia had a significantly higher risk of new-onset peritonitis ( HR=1.013, 95% CI 1.003-1.024, P=0.014). Conclusion:The mean albumin<35 g/L and prolong duration of hypoalbuminemia are independent risk factors of PD-related peritonitis in PD patients.
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Objective:To explore the relationship between metabolic acidosis and cardiac valve calcification in maintenance hemodialysis (MHD) patients in the Pearl River Delta Region.Methods:Patients on MHD greater than 3 months who were treated in 10 blood purification centers in the Pearl River Delta Region from July 1 to September 30, 2019 were selected for this multicenter cross-sectional study. Based on a Doppler ultrasound, MHD patients were further divided into non-valve calcification group and valve calcification group. The demographics data, frequency of dialysis, blood pressure, single pool Kt/V(spKt/V), dialysis medications and laboratory data were collected and compared. Spearman correlation analysis was used to analyze the correlation between serum carbon dioxide combining power (CO 2CP) and cardiac valve calcification. Multivariate logistic regression model was used to analyze the influencing factors of cardiac valve calcification. Results:A total of 664 MHD patients were included in this study, with age of (57.0±14.2) years old and dialysis age of 43.0 (22.3, 71.7) months, including 395 males (59.5%) and 269 females (40.5%). Among them, there were 119 patients (17.9%) with diabetes and 186 patients (28.0%) with dialysis 2 times per week. There were 329 patients (49.5%) in the valve calcification group, and 335 patients (50.5%) in the non-valve calcification group. Compared to those in non-valve calcification group, valve calcification group had longer duration of dialysis, higher proportion of patients with dialysis 2 times per week, higher levels of diastolic blood pressure, fasting blood glucose, intact parathyroid hormone and ferritin, higher proportion of patients with blood CO 2CP<19 mmol/L (median CO 2CP), higher proportion of patients on usage of calcium channel blocker, angiotensin converting enzyme inhibitor/angiotensin receptor blocker, α-receptor blocker, β-receptor blocker, calcitriol and lanthanum carbonate (all P<0.05), while the levels of spKt/V, hemoglobin, serum CO 2CP, corrected calcium, blood phosphorus, blood alkaline phosphatase, albumin, total cholesterol, triacylglycerol, low-density lipoprotein, high-density lipoprotein, transferrin saturation, and the proportion of patients on usage of sevelamer and cinacalcet were lower (all P<0.05). Spearman analysis showed significant negative correlation between serum CO 2CP and valve calcification ( rs=-0.697, P<0.001). Multivariate logistic regression analysis showed that dialysis performed twice a week ( OR=2.789, 95% CI 1.232-6.305, P=0.014), blood total cholesterol ( OR=1.449, 95% CI 1.014-2.071, P=0.042), CO 2CP<19 mmol/L ( OR=22.412, 95% CI 10.640-47.210, P<0.001) were the influencing factor of valve calcification in MHD patients. Conclusions:MHD patients with cardiac valve calcification have significant acid loading. Metabolic acidosis is an independent influencing factor for cardiac valve calcification in MHD patients.
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<p><b>OBJECTIVE</b>To explore the value of baseline serum alkaline phosphatase (ALP) for predicting 2-year fracture in patients with chronic kidney disease (CKD) on maintenance dialysis.</p><p><b>METHODS</b>A total of 139 patients with CKD undergoing maintenance dialysis in our hospital were enrolled in this study. According to the median serum ALP level, the patients were divided into high ALP and low ALP groups. The demographic and clinical data of the patients including dialysis duration, serum calcium level, serum phosphorus level, and serum intact parathyroid hormone level were recorded, and their bone mineral density of the femur and the lumbar spine was measured using dual energy X-ray absorptiometry. The patients were followed up for 2 years and fracture events were recorded. The risk factors of fracture were analyzed using logistic regression analysis, and their predictive value for fracture was analyzed using receiver-operating characteristic (ROC) curve.</p><p><b>RESULTS</b>The mean baseline serum ALP level was 132.55±167.68 U/L in these patients, significantly higher than that in the normal population (=2.816, =0.006). Baseline serum ALP level was negatively correlated with the bone mineral density of the lumbar spine (=-0.203, =0.006) and the femur (=-0.196, =0.021). Fractures occurred in 21 (15.1%) of the patients during the 2-year follow-up, and the fracture rate was significantly higher in patients with high ALP levels. Logistic regression analysis identified serum ALP level as an independent risk factor of fracture (OR: 1.010, =0.001, 95%CI: 1.004-1.016). The areas under the ROC curve were 0.900 and 0.768 for serum ALP level and intact parathyroid hormone level in predicting 2-year fractures, respectively.</p><p><b>CONCLUSIONS</b>Serum ALP may serve as a good indicator for predicting 2-year fractures in patients with CKD on maintenance dialysis.</p>
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Objective To explore the role and mechanism of microRNA-15b in the regulation of epithelial-mesenchymal transition (EMT) of human peritoneal mesothelial cells (HPMCs).Methods PCR assay was used to determine the expression of microRNA-15b in the HMrSV5 induced by 138mmol/L high glucose for 24 h.MicmRNA-15b mimic or inhibitor was transfected into human peritoneal mesothelial cells (HMrSV5) to over-express or down-regulate microRNA-15b.The cells were then incubated with 138 mmol/L high glucose for 24 h,and the expressions of E-cadherin(E-Cad),Vimentin (VIM),Fibronectin(FN) and Smad7 were detected by real-time PCR and Western blotting respectively.Results microRNA-15b in the HMrSV5 ceils was over-expressed and down-regulated.Increased level of microRNA-15b was obtained in HMrSV5 cells treated with high glucose.In vitro,high glucose led to the up-regulation of vimentin as well as fibronectin and the down-regulation of E-cadherin in HMrSV5 cells (all P ＜ 0.05),which indicated EMT and fibrosis.Suppression of microRNA-15b by transfection with microRNA-15b inhibitor partially reversed the EMT and fibrosis changes (P ＜ 0.05),while over-expression of microRNA-15b by transfection with microRNA-15b mimic obviously enhanced the EMT and fibrosis changes (P ＜ 0.05).Conclusions MicroRNA-15b mediates high glucose induced EMT in human peritoneal mesothelial cells by the inhibition of Smad7 possibly.MicroRNA-15b maybe a new target for the prevention and treatment of peritoneal fibrosis during peritoneal dialysis (PD).
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Objective To investigate the role of protein phosphorylation in Pseudomonas aeruginosa (P.aeruginosa) strains in response to stress triggered by mouse macrophages.Methods The strong cation exchange-immobilized metal affinity chromatography (SCX-IMAC) was performed to enrich phosphopeptides.The nanoscale liquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS) was carried out to identify and analyze phosphoproteome.Results Fourteen phosphopeptides from twelve proteins were identified within thirty-one phosphorylation sites on serine,threonine and tyrosine residues.Fifty percent of these phosphorylated proteins were membrane proteins,indicating that their phosphorylation modification was more critical for bacteria in response to the stress.In terms of biological process of Gene Ontology,these identified proteins were involved in stress response,iron transport,anaerobic respiration,response to hydrogen peroxide and signal transduction by phosphorylation,etc.Conclusion These phosphorylated proteins in P.aeruginosa strains are necessary for signal transduction and their response to harsh environment within the macrophages,such as iron limitation,hypoxia and oxidative stress.This study provides evidence for further investigation on virulence and pathogenesis of P.aeruginosa.
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The neurotoxin peptide, hainantoxin-Ⅵ (HNTX- Ⅵ), has been isolated from the venom of Chinese tarantula Ornithoconus hainana by a combination of ion exchange chromatography and reverse phase HPLC. The toxin was found to contain 34 amino acid residues with 6 conserved cysteine residues. The effects of HNTX-VI on voltage-gated sodium channels were studied via whole-cell patch clamp techniques. Although several inhibitors of mammalian neuronal sodium channel activation (hainantoxin Ⅰ-Ⅴ) had been characterized from the same venom, the present study indicated that HNTX-Ⅵ had the ability to slow the inactivation kinetics of the sodium channels in Cockroach Periplaneta Americana dorsal unpaired median (DUM) neurons in a similar manner to δ-atractoxins. After HNTX-Ⅵ treatment, steady-state sodium channel inactivation became incomplete, leading to a non-inactivating component at potentials more positive than - 55 mV. The novel function of the tarantula toxin HNTX-Ⅵ not only supplies a useful tool for exploring the gating mechanisms of sodium channels but also provides theoretical foundations for exploiting novel and safe insecticides.