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BACKGROUND Studies suggested the association between blood flow rate (BFR) and mortality might be beyond dialysis adequacy. This study aimed to explore if BFR is an independent predictor of clinical outcomes in Chinese hemodialysis (HD) patients. METHODS This study included data from patients in China Dialysis Outcomes and Practice Patterns Study (DOPPS) Phase 5. Patients with a record of BFR were included, and demographic data, comorbidities, hospitalization, and death records were collected. Associations between BFR and all-cause mortality and hospitalization were analyzed using Cox regression models. RESULTS One thousand four hundred twelve (98.9%) patients were included. Most patients were with BFR

Stimuli-responsive hydrogels are flourishing; however, a multiresponsive luminescent hydrogel actuator in which the stimuli do not interfere with each other is still difficult to produce. Here, a smart luminescent bilayer hydrogel actuator with shape memory and reversible luminescence switch behaviors under the co-stimulation of pH and heating is reported. Under alkaline condition, chitosan-containing layer generates physical microcrystals to fix the temporary shape of the actuator while lanthanide emits bright luminescence. Upon acid treatment, the actuator recovers to its original shape and the luminescence is quenched since the "antenna effect" between organic ligand and lanthanide ions is disrupted. It is to be noticed that this multiresponsive cycle can be repeated several times without interfering each other. This work is expected to have potential application prospects in the fields of biomimetic soft robots, sensors, and camouflage.

A comprehensive analysis of the intake valve opening duration (IVOD) effects on the performance of an Atkinson cycle engine is conducted in this work using numerical simulation and experimental validation. Through one-dimensional simulation, the relationship between the range of IVOD and the compression ratios is firstly investigated under the constraint of compression pressure. Two representative IVOD, 295 and 314°CA, are then respectively applied to the performance simulation and experiment of a practical Atkinson cycle engine. The simulation shows the combination of a late intake valve opening timing (IVO) angle and a late exhaust valve opening timing (EVO) angle is profitable for improving the fuel economy under part load operating conditions (i.e. 2000 rpm@2 bar and 3000 rpm@3 bar). The experimental results present the Atkinson cycle engine under both IVOD scenarios considerably improves the brake specific fuel consumption (BSFC) and reduces the pumping mean effective pressure (PMEP) compared to those of the original Otto cycle engine. Meanwhile, the comparison between two IVOD scenarios show that the shorter IVOD leads to an improvement of indicated thermal efficiency, especially at lower load. Considering fuel economy, a shorter IVOD is more favorable at part load for the Atkinson cycle engine. Two main contributions of this work are to numerically quantify the IVOD range for the Atkinson cycle engine under part load, and to experimentally validate the effectiveness of simulation. The findings of this work are expected to support the design of Atkinson cycle engines and provide a guideline of IVOD optimization under part load.

Background: Hemodialysis (HD) patients usually have impaired physical function compared with the general population. Self-reported physical function is a simple method to implement in daily dialysis care. This study aimed to examine the association of self-reported physical function with clinical outcomes of HD patients. Methods: The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective cohort study. Data on 1,427 HD patients in China DOPPS5 were analyzed. Self-reported physical function was characterized by 2 items of “moderate activities limited level” and “climbing stairs limited level.” Demographic data, comorbidities, hospitalization, and death records were collected from patients’ records. Associations between physical function and outcomes were analyzed using COX regression models. Results: Compared to “limited a lot” in moderate activities, “limited a little” and “not limited at all” groups were associated with lower all-cause mortality after adjusted for covariates (HR: 0.652, 95% CI: 0.435–0.977, and HR: 0.472, 95% CI: 0.241–0.927, respectively). And, not limited in moderate activities was associated with lower risk of hospitalization than the “limited a lot” group after adjusted for covariates (HR: 0.747, 95% CI: 0.570–0.978). Meanwhile, compared to “limited a lot” in climbing stairs, “limited a little” and “not limited at all” groups were associated with lower all-cause mortality (HR: 0.574, 95% CI: 0.380–0.865 and HR: 0.472, 95% CI: 0.293–0.762, respectively) but not hospitalization after fully adjusted. Conclusion: Higher limited levels in self-reported physical function were associated with higher risk of all-cause mortality and hospitalization in HD patients.

Hydrogen is regarded as a promising alternative fuel in the future. The direct-injection (DI) hydrogen engine has been demonstrated to offer large power without the risk of abnormal combustion. For the engine test of combustion analysis, the piezoelectric transducer measures the dynamic cylinder pressure data rather than the absolute one. The traditional method of absolute cylinder pressure correction is normally based on the polytropic index. This paper investigated the polytropic index effects by injection duration, start timing of injection and speed based on a 2.0 L direct-injection hydrogen engine. The experiments found that, since the injection of large volume hydrogen leads to approximately 0.8 bar increase of cylinder pressure in the compression stroke, the traditional correct method is not suitable for the DI hydrogen engine. What's more, the polytropic index drops from 2.2 to 1.22 with the changes of the crank angle and is sensitive to the concentration of the hydrogen. The study of the instantaneous polytropic index can not only be used to calculate the accurate heat release rate but also guide the research of the heat transfer of the DI hydrogen engine. The average polytropic index of 1.32 provides a new reference for the absolute cylinder pressure correction of the DI hydrogen engine.

Introduction Long-term use of unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) causes bone loss and osteoporosis in patients not receiving hemodialysis. This study aimed to investigate the effect of UFH and LMWH on bone mineral density (BMD) in patients undergoing maintenance hemodialysis (MHD). Methods Patients undergoing MHD using UFH or LMWH as anticoagulants were enrolled. BMD (in g/cm2 ), T-score and Z-score (BMDs) were measured at the lumbar spine and femur neck using dual-energy X-ray absorptiometry (DXA) at baseline and 2 years later. Patient demographics and clinical indices were collected. Correlation analysis was used to identify significant predictors of bone loss. Multiple linear regression was used to explore the relationship between heparin type and bone loss progression. Findings A total of 104 patients were enrolled and completed the baseline BMD test; 72 completed the test again 2 years later. Six patients were excluded because they used both UFH and LMWH. Although BMD decreased in some patients in the UFH group, a slight increase in the BMD was observed on an average in the LMWH group after 2 years. The mean change in BMD (in g/cm2 ) [0(-0.03,0.04) vs. 0.04(0,0.06), P = 0.023], T-score [0(-0.40,0.30) vs. 0.35(-0.03,0.53), P = 0.038], and Z-score [0.10(-0.30,0.40) vs. 0.45(0.08,0.63), P = 0.031] in the lumbar spine in the UFH group was lower than those in the LMWH group. Femur neck BMD did not change significantly. In a linear regression model, after adjusting for diabetes mellitus, parathyroid hormone, and serum phosphate, we did not find an association between heparin substances and BMD. Discussion UFH might be associated with loss of lumbar spine BMD in patients undergoing MHD.

(1) Background: Recently more and more Chinese clinical studies have been conducted to compare the efficacy and safety of roxadustat with erythropoiesis-stimulating agents (ESAs) in hemodialysis (HD) patients. We aimed to assess the efficacy and safety of roxadustat in Chinese HD patients. (2) Methods: The PubMed, Embase, the Cochrane Library, Web of Science, WanFang, China National Knowledge Infrastructure (CNKI), SinoMed, and VIP databases were searched from their inception to July 2022 for randomized controlled trials (RCTs) that compared the efficacy and safety of roxadustat to those of ESAs in treating anemia in Chinese HD patients. (3) Results: Twenty-one RCTs involving 1408 patients were enrolled. Our study showed that the improvement of hemoglobin (Hb) levels and iron metabolism were significantly higher in the roxadustat group than in the ESA group. Additionally, the total adverse events risk was significantly lower in the roxadustat group. (4) Conclusions: In this meta-analysis, we found that roxadustat was more effective and safer than ESAs in treating anemia in Chinese HD patients.

Background Mortality risk for hemodialysis (HD) patients varies by country and ethnicity. Here, mortality rate and its related risk factors in Chinese HD patients from the Dialysis Outcomes and Practice Patterns Study (DOPPS) were investigated.Methods Data from China DOPPS phase 5 (2012–2015) were used. Patients’ demographics, assigned primary causes of end stage Kidney disease (ESKD), comorbidities, dialysis prescription, laboratory values, date and cause for death were analyzed. Cox proportional hazards models were used to assess the association of patient characteristics and treatments with mortality.Results 1427 HD patients were enrolled. The mean age was 59.4 ± 14.9 years. The median follow-up time was 1.9 (1.1–2.1) years. There was total 205 deaths with at least 103 from cardiovascular disease (50.2%). The overall mortality rate was 8.8 per 100 patient-years. In the multivariate COX model, older, serum albumin (Alb 9/L, pulse pressure (PP) > 63mmHg, and congestive heart failure history were independent risk factors for all-cause mortality.Conclusions Attention should be paid to patients who were older, with lower Alb and blood platelets level, higher PP and congestive heart failure history. Our results highlighted that there might be some modifiable risk factors for patients’ survival, such as Hgb, Alb, blood platelets, and blood pressure management.

Objective: To investigate the occurrence of vascular calcification (VC) in different types of arteries in patients with maintenance peritoneal dialysis (PD) patients and its influencing factors. Methods: This study enrolled PD patients with stable status who has received PD treatment for more than 6 months in Peking University People’s Hospital. We used plain X-ray films of abdomen, pelvis, and hands to quantitatively evaluate VC of large artery (abdominal aorta, iliac artery), medium artery (femoral artery, radial artery), and small artery (finger arteries). Two radiologists read and scored radiographs blindly. Demographic data, clinical characteristics, Charlson comorbidity index (CCI), baseline and time-average laboratory indices including parameters of calcium phosphorus metabolism, serum albumin, PD adequacy were collected. A logistic regression model was used to estimate the influencing factors of different sites of VC. Results: (1) 154 PD patients were enrolled in this study: seventy-eight males, mean age was 60.4 ± 13.9 years, and median PD duration was 24 (16.39) months. The major primary disease was diabetic nephropathy (39%). (2) Among the 154 PD patients, the proportion of calcification of large artery was the highest (found in 100 patients, accounting for 64.9%); then the medium artery (66, 42.9%); and 15 of small artery, accounting for 9.7%. (3) Logistic regression showed that older age, longer dialysis duration, lower baseline serum intact parathyroid hormone (iPTH), and higher CCI scores were independent risk factors of large artery calcification (p < 0.05), and higher CCI scores, higher baseline serum triglycerides (TG), lower baseline serum iPTH, and time-average iPTH were independent risk factors of medium and small arteries. Conclusions: In PD patients, the occurrence of large artery calcification was higher than others. Among different sites of VC, the abdominal aortic calcification was most likely to occur, and the proportion of small artery calcification was low. Calcification of medium and small arteries can exist alone without calcification of large artery. Large artery calcification was more likely to occur in patients with older age, longer dialysis duration, lower baseline serum iPTH levels and higher CCI scores. Patients with higher CCI scores, higher baseline TG and lower baseline iPTH, and time-average iPTH were more likely to develop small and medium artery calcification.

The number of patients on hemodialysis (HD) is rapidly increasing in China. As an Asian country with a large number of HD patients, understanding the status of Chinese HD patients has a special significance. We reported here the baseline data for China Dialysis Outcomes and Practice Pattern Study Phase 5 (DOPPS5). The DOPPS is an international prospective, observational cohort study. Patients were restricted to the initial sample of patients who participated in China DOPPS5. We summarized the baseline demographic and clinical data of patients. Results were weighted by facility sampling fraction. 1186 patients were initial patients in China DOPPS5. The mean age was 58.7 ± 3.5 years, with 54.6% males. The median dialysis vintage was 3.4 (1.5, 6.3) years. The main assigned primary end-stage kidney disease (ESKD) causes was chronic glomerulonephritis (45.9%), followed by diabetes (19.9%). 17.6% patients had hepatitis B infection, and 10.0% patients had hepatitis C infection. 25.9% patients had a single-pooled Kt/V 3.5 g/dl. 18.8% patients had hemoglobin

Background and Aims Mortality risk for maintenance hemodialysis (MHD) patients varies by country and ethnicity. Here, mortality rate and its related risk factors in Chinese HD patients from Dialysis Outcomes and Practice Patterns Study (DOPPS) were studied. Method Data from the China DOPPS phase 5 (2012-2015) were used. All included patients were followed to the end of the study. Patients’ demographics, primary cause of end stage renal disease (ESRD), comorbidities, abstracted dialysis prescription, laboratory values, date of death, and causes for death were analyzed. All-cause mortality (per 100 patient-years) was calculated. We examined clinical and laboratory differences between died and survived patients. Cox regression was used to explore risk factors of death, accounting for facility clustering and adjusted for case-mix (age, sex, vintage, and comorbid conditions), and laboratory values (albumin, hemoglobin, white blood count, sodium). Results There were 1427 MHD patients were enrolled. The mean age at dialysis initiation was 59.4±14.9 years (table 1). The median follow-up time was 1.9 years (IQR 1.1-2.1). There were total 205 deaths. The overall mortality rate was 8.8 per 100 patient-years. Death from cardiovascular disease (CVD) occurred in 50.2% of the patients. Compared with survived patients, patients with mortality were older (58.5 Vs. 70.0 y), more likely with diabetes, with lower pre-dialysis albumin level (Pre-ALB) or hemoglobin level (Pre-HGB), with lower pre or post dialysis diastolic blood pressure (DBP), with some comorbidities and less likely with fistula as their blood access (table 2). Cox regression revealed that risk factors for higher mortality were older age, lower Pre-ALB level, higher pre-dialysis DBP and with CHF, hepatitis, hypertension, and lung disease. Conclusion CVD constituted half of the death reasons for Chinese dialysis patients. Our analysis highlighted that there are some modifiable risk factors for patients’ survival. Attention should be paid to patients who were older, with lower Pre-ALB level, higher pre-dialysis DBP and with CHF, hepatitis, hypertension, and lung disease.

Background: Hemodialysis (HD) patients usually have impaired physical function compared with general population. Self-reported physical function is a simple method to implement in daily dialysis care. This study aimed to examine the association of self-reported physical function with clinical outcomes of HD patients.Methods: Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective cohort study. Data on 1427 HD patients in China DOPPS5 were analyzed. Self-reported physical function was characterized by 2 items of ‘moderate activities limited level’ and ’climbing stairs limited level’. Demographic data, comorbidities, hospitalization and death records were collected from patients’ records. Associations between physical function and outcomes were analyzed using COX regression models. The generalized linear mixed models were used to examine correlates of physical function limited level.Results: Compared to ‘limited a lot’ in moderate activities, ‘limited a little’ and ‘not limited at all’ groups were associated with lower all-cause mortality after adjusted for covariates (HR: 0.652, 95% CI: 0.435-0.977 and HR: 0.472, 95% CI: 0.241-0.927, respectively). And not limited in moderate activities was associated with lower risk of hospitalization compared with ‘limited a lot’ group after adjusted for covariates (HR: 0.747, 95% CI: 0.570-0.978). Meanwhile, compared to ‘limited a lot’ in climbing stairs, ‘limited a little’ and ‘not limited at all’ groups were associated with lower all-cause mortality (HR: 0.574, 95% CI: 0.380-0.865 and HR: 0.472, 95% CI: 0.293-0.762, respectively) but not hospitalization after fully adjusted. Factors including old age, female gender, longer dialysis vintage, catheter use, low serum albumin and combining with diabetes, coronary artery disease and cerebrovascular disease were related to higher limited levels of physical function (P < 0.05).Conclusion: Higher limited levels in self-reported physical function were associated with higher risk of all-cause mortality and hospitalization in HD patients.

Additional file 1.

Peritonitis is the most common complication in patients undergoing peritoneal dialysis (PD). Peritoneal dialysis-related peritonitis caused by Brucella species has been reported in only 7 patients before. Here, we report a further case of Brucella peritonitis. This patient was successfully treated with both intraperitoneal and prolonged oral antibiotics, without removal of the PD catheter. We review relevant literature and make recommendations for the diagnosis and treatment of Brucella PD-related peritonitis from the cumulative published clinical experience.

Luminescent hydrogels have shown great potential in many fields, such as lighting, display, imaging, and sensing, because of their unique optical properties, biocompatibility, and easy processing. Organic-inorganic hybrid self-assembly can not only enhance the hydrogels' mechanical strength, but also retain their self-healing ability. Herein, a luminescent supramolecular hydrogel is reported, which is formed via self-assembly of the negatively charged Laponite nanosheets and cationic lanthanide coordination polymer. The corresponding results reveal that the multiple binding interaction between Laponite and the polymeric binder is vital for improving the mechanical performance of the obtained luminescent supramolecular hydrogel.

Background In recent years, there has been a growing concern that abdominal aortic calcification (AAC) has a predictive effect on the prognosis of patients with end-stage renal disease (ESRD). However, whether other vascular calcification (VC) can predict the occurrence of adverse events in patients, and whether it is necessary to assess the calcification of other blood vessels remains controversial. This study aimed to assess VC in different sites using X-ray films, and to investigate the predictive effects of VC at different sites on all-cause mortality and cardiovascular (CV) mortality in peritoneal dialysis (PD) patients. Methods The data of Radiographs (lateral abdominal plain film, frontal pelvic radiograph and both hands radiograph) were collected to evaluate the calcification of abdominal aorta, iliac artery, femoral artery, radial artery, and finger arteries. Patients’ demographic data, clinical characteristics, laboratory data were recorded. The total follow-up period was 8 years, and the time and cause of death were recorded. Survival curves were estimated using Kaplan-Meier analysis. COX regression analysis was used to examine independent predictors of all-cause mortality and CV mortality. Results One hundred fifty PD patients were included, a total of 79 patients (52.7%) died at the end of follow-up. After adjusting variables in the multivariate COX regression analysis, AAC was an independent predictor of all-cause mortality in PD patients (HR = 2.089, 95% CI: 1.089–4.042, P = 0.029), and was also an independent predictor of CV mortality (HR = 4.660, 95% CI: 1.852–11.725, P = 0.001). We also found that femoral artery calcification had a predictive effect on all-cause and CV mortality. But the calcification in iliac artery, radial artery, and finger arteries were not independent predictors of patients’ all-cause and CV mortality in PD patients. Conclusion AAC was more common in PD patients and was an independent predictor of all-cause mortality and CV mortality. The femoral artery calcification also can predict the mortality, but the calcification of iliac artery, radial artery, and finger arteries cannot predict the mortality of PD patients.

Aim Several studies have verified that unfractionated heparin (UFH) and low molecular heparin (LWMH) can induce bone loss, and bone mineral density has been inversely associated with vascular calcification in some clinical researches. But few have focused on the relationship between types and dosages of heparin and the progression of vascular calcification. We observed the progression of coronary artery calcification (CAC) in maintenance haemodialysis (MHD) patients who were treated with UFH and LMWH. Methods This was a prospective prevalent cohort study of MHD patients. Computed tomography was performed at enrolment and 2 years after enrolment, and CAC score was obtained. Demographic and clinical data, baseline and time‐average laboratory indices were collected. Multiple linear regression and logistic regression were used to estimate the influencing factors of progression of CAC. Results In this study, (i) we initially enrolled 69 HD patients, and then 56 patients finished the follow‐up. (ii) Among the total 56 patients, 27 patients (48.2%) were treated with UFH, 14 (25.0%) with LMWH and 15 (26.8%) with both. The median baseline CAC scores of three groups (UFH, LMWH and both users) were 91.0 (1.0, 1052.0), 134.0 (0, 1292.0) and 250.5 (27.0, 1139.0), respectively, with no significant difference (P = 0.663); the median CAC progression scores were 42.0 (0, 364.0), 172.0 (7.0, 653.0) and 118.5 (0, 434.0), respectively, with no significant difference (P = 0.660). (iii) Pearson and spearman correlation analysis shown that the progression of CAC was not associated with cumulative dosage of heparin used. (iv) After adjusted for diabetes mellitus, time‐averaged intact parathyroid hormone, phosphate and alkaline phosphatase, logistic regression analysis showed using different types of heparin was not an independent risk factor for CAC progression; and multiple linear regression analysis showed that the type of heparin used was not associated with CAC progression. Conclusion There were no significant differences in the effects of the types and dosages of heparin on CAC progression in patients on haemodialysis., SUMMARY AT A GLANCE This study shows no significant effects of different types and dosages of heparin on baseline and progression of coronary artery calcification in hemodialysis patients.

The Atkinson cycle engine plays a key role in the development of hybrid electronic vehicle (HEV) because of greater fuel economy than Otto cycle engine. The thermodynamic analysis shows Atkinson cycle has the significant advantage of cycle efficiency and the ratio of expansion ratio to effective compression ratio and pressure rise ratio have great influence on efficiency. A performance optimization strategy for the Atkinson cycle engine is proposed through analysis of compression ratio range according to cycle efficiency at small pressure rise ratio and optimization of the high compression ratio and the late intake valve closure (LIVC) under the compression pressure constraint. The experimental results show significant improvements in pumping losses and fuel economy are achieved, thus verifying verifies the effectiveness of the optimization strategy and brake specific fuel consumption (BSFC) of is improved by 9% at 2000 rpm@2 bar and 8% at 3000 rpm@3 bar, respectively. The fuel-saving mechanism is investigated in depth. The increase of mechanical efficiency due to the reduction in pumping mean effective pressure (PMEP) is the main reason for the fuel economy improvement at low and medium load, while the increase of indicated thermal efficiency is the main reason at high load. The increase in intake pressure is the main reason for the decrease in PMEP. The Atkinson cycle engine can achieve more obvious constant volume combustion and the combustion quality has been greatly improved. These findings can be used as guidelines for the development of new Atkinson cycle engines.

Background Abdominal aortic calcification (AAC) has a pretty high incidence in dialysis patients and may be associated with their prognosis. AAC can be assessed by abdominal CT or X-ray. We determined to investigate whether the occurrence of AAC is associated with all-cause mortality and cardiovascular (CV) events in dialysis patients through this meta-analysis and systematic review. Methods A comprehensive literature search was conducted using the PubMed, Cochrane library, Embase, Medline databases to collect cohort studies investigating whether AAC is associated with all-cause mortality and CV events of patients, and we also searched gray articles and conferences abstracts. Meta-analysis was performed by STATA software. Pooled results were expressed as hazard ratio (HR) with corresponding 95% confidence intervals (CI). Fixed-effect models were used to pool the HR of each trial. Results 10 studies (2,724 dialysis patients) were identified. The presence of AAC was associated with increased risk for all-cause mortality among dialysis patients (HR, 2.84; 95% CI, 2.03–3.98; I2 = 9.8%; P = 0.354). Meanwhile, there was an association between AAC and increased risk for all CV events (fatal and non-fatal) in patients (HR, 2.04; 95% CI, 1.51–2.76, I2 = 44.6%; P = 0.125). 3 studies presented their endpoint as CV mortality, and the pooled HR was 2.46 (95%CI 1.38–4.40; I2 = 0.0%; P = 0.952). There were also 2 studies that reported their primary endpoint as all-cause mortality and CV events, and the pooled HR was 5.72 (95% CI 3.24–10.10; I2 = 0.0%; P = 0.453). Conclusions Among patients treated with dialysis, AAC is associated with adverse outcomes, including all-cause mortality and CV events (fatal and non-fatal). The abdominal X-ray or CT scan can be used as a useful added method to evaluate the patient’s calcification. This may provide reasonable data for estimating the risk of adverse events in dialysis patients, which is helpful in guiding clinical treatment and improving the prognosis of dialysis patients.