The risk factors and clinical outcomes in hepatitis B seropositive and seronegative renal transplant patients

INTRODUCTION

Hepatitis B virus (HBV) infection is prevalent in Asia including Taiwan. We retrospectively evaluated the risk of HBV reactivation and clinical outcomes in HBV+ and HBV- kidney transplant recipients.

METHODS

Patients who underwent kidney transplantation between January 2004 and December 2021 were reviewed. The outcomes of interest included risks of HBV reactivation and patient/graft survival.

RESULTS

We identified 337 patients (47.5 ± 12 years) were enrolled in our final cohort. Fifty-two (15.4%) had HBsAg positive at the time of transplantation. Seventeen developed viral reactivations, with 41.2% of them accompanied by active hepatitis. The graft survival, acute rejection rate, and cancer development after kidney transplantation did not differ in terms of HBsAg status. The Cox multivariate analysis indicated the HBV reactivation risk was increased by a lack of pre-transplant anti-HBV medication [hazard ratio (HR), 5.95; 95% confidence interval (CI), 1.31-27.02; P = 0.021 or an absence of lifelong antiviral therapy [HR, 3.14; 95% CI, 1.01-9.74; P = 0.047] Conclusion: Individuals, independent of HBsAg status, had similar prognosis in terms of patient and graft survival, acute rejection rate, and cancer development. The absence of either pre-transplant anti-HBV medication or lifelong antiviral therapy was significantly associated with an increased risk of HBV reactivation.

Survival benefit of a third dose of the COVID-19 vaccine among hemodialysis patients: A prospective cohort study

BACKGROUND

Hemodialysis (HD) patients are particularly vulnerable to severe coronavirus disease 2019 (COVID-19) due to their immunocompromised state and comorbid conditions. Timely vaccination could be the most effective strategy to reduce morbidity and mortality. However, data on the survival benefit of the COVID-19 vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and death among HD patients are limited, especially during the Omicron-dominant period.

METHODS

In this prospective hospital-based cohort study, we identified HD patients from July 1, 2021, to April 29, 2022. The patients were divided into fully vaccinated and partially vaccinated groups. We compared the humoral response, risk of developing SARS-CoV-2 infection, and all-cause mortality between the two groups.

RESULTS

Among the 440 HD patients included, 152 patients were fully vaccinated, and 288 patients were partially vaccinated. Patients in the fully vaccinated group exhibited higher anti-spike protein receptor-binding domain (S protein RBD) antibody levels and lower risks of all-cause mortality (adjusted hazard ratio, 0.35; 95% confidence interval, 0.17-0.73; p = 0.005) than the partially vaccinated group. However, the risk for SARS-CoV-2 infection did not significantly differ between the two groups. Irrespective of the number of vaccinations, the risk of all-cause mortality was lower in patients with anti-S protein RBD antibody levels in the higher tertile.

CONCLUSION

A third dose of the COVID-19 vaccine was associated with a decreased risk of all-cause mortality among HD patients during the Omicron-dominant period. A higher post-vaccination anti-S protein RBD antibody level was also associated with a lower risk of mortality.

Circulating Osteocalcin Fractions are Associated with Vascular Calcification and Mortality in Chronic Hemodialysis Patients

BACKGROUND

Vascular calcification, a component of chronic kidney disease-mineral and bone disorder (CKD-MBD), is prevalent in patients with end-stage kidney disease (ESKD) and contributes to high mortality. However, the association between the blood level of total osteocalcin (OC) and vascular calcification and mortality remains inconclusive. We, therefore, investigated whether different OC fractions can serve as biomarkers of vascular calcification and mortality in the ESKD population.

METHODS

This observational cohort study enrolled patients on maintenance hemodialysis. Plasma carboxylated OC (cOC), uncarboxylated OC (ucOC), and intact parathyroid hormone (PTH) were measured. The percentage of carboxylated OC (%cOC) was calculated as dividing cOC by total OC. The vascular calcification severity was defined by an aortic calcification grade. The patients were followed for three years and one month.

RESULTS

A total of 184 patients were enrolled. In the multivariable logistic regression, plasma %cOC, but not cOC or ucOC, was independently associated with the severity of vascular calcification (OR 1.019, p = 0.036). A significant U-shaped correlation was found between plasma %cOC and PTH (p = 0.002). In the multivariable Cox regression, patients with higher plasma %cOC had a higher risk of mortality (quartiles Q4 versus Q1-Q3, HR 1.991 [95% CI: 1.036-3.824], p = 0.039).

CONCLUSIONS

In patients undergoing chronic hemodialysis, plasma %cOC positively correlated with vascular calcification and exhibited a U-shaped correlation with PTH. Furthermore, a higher plasma %cOC was associated with increased mortality. These findings suggest that plasma %cOC may serve as a biomarker for CKD-MBD and a predictor of clinical outcomes in chronic hemodialysis patients.

Lifetime prediction of encapsulated CdSexS1-x quantum platelets for color conversion in high luminance LED microdisplays

The LED technology is seen today as the most promising approach to manufacture high luminance color microdisplays for augmented reality application. So far, it mostly involves blue micro-LED technology and quantum dots-based layers for green and red color generation by light down-conversion. Despite significant progress, the viability of this technology still raises many questions. Among them, the stability of the color conversion layer under nominal display operating conditions is still an issue which has not been thoroughly addressed yet. This paper provides experimental data on the aging behavior of CdSe_xS_1-x quantum platelets (QP) for blue-to-red conversion, under a wide range of blue irradiation power. A modeling of the photoluminescence (PL) decrease versus aging time is proposed, that enables to reliably predict the lifetime of a color LED microdisplay in real operating conditions. At room temperature, the alumina encapsulated CdSe_xS_1-x QPs exhibit a lifetime (t₇₀) of 35,000 h under operating conditions representative of a microdisplay emitting 100,000 nits white light, in video mode. With an average daily use of 3 hours, it would represent for a microdisplay more than 30 years. In addition, the study highlights that display heating induces a lifetime decrease related to a thermally activated enhancement of the annihilation rate of PL emission centers. As a result, a display operated at 100,000 nits and 45°C would see its lifetime t₇₀ reduced by a factor 4 (∼8 years), which remains acceptable for most micro-display applications.

Prediction of the risk of developing end-stage renal diseases in newly diagnosed type 2 diabetes mellitus using artificial intelligence algorithms

OBJECTIVES

Type 2 diabetes mellitus (T2DM) imposes a great burden on healthcare systems, and these patients experience higher long-term risks for developing end-stage renal disease (ESRD). Managing diabetic nephropathy becomes more challenging when kidney function starts declining. Therefore, developing predictive models for the risk of developing ESRD in newly diagnosed T2DM patients may be helpful in clinical settings.

METHODS

We established machine learning models constructed from a subset of clinical features collected from 53,477 newly diagnosed T2DM patients from January 2008 to December 2018 and then selected the best model. The cohort was divided, with 70% and 30% of patients randomly assigned to the training and testing sets, respectively.

RESULTS

The discriminative ability of our machine learning models, including logistic regression, extra tree classifier, random forest, gradient boosting decision tree (GBDT), extreme gradient boosting (XGBoost), and light gradient boosting machine were evaluated across the cohort. XGBoost yielded the highest area under the receiver operating characteristic curve (AUC) of 0.953, followed by extra tree and GBDT, with AUC values of 0.952 and 0.938 on the testing dataset. The SHapley Additive explanation summary plot in the XGBoost model illustrated that the top five important features included baseline serum creatinine, mean serum creatine within 1 year before the diagnosis of T2DM, high-sensitivity C-reactive protein, spot urine protein-to-creatinine ratio and female gender.

CONCLUSIONS

Because our machine learning prediction models were based on routinely collected clinical features, they can be used as risk assessment tools for developing ESRD. By identifying high-risk patients, intervention strategies may be provided at an early stage.

Unintrusive multi-cancer detection by circulating cell-free DNA methylation sequencing (THUNDER): development and independent validation studies

BACKGROUND

Early detection of cancer offers the opportunity to identify candidates when curative treatments are achievable. The THUNDER study (THe UNintrusive Detection of EaRly-stage cancers, NCT04820868) aimed to evaluate the performance of ELSA-seq, a previously described cfDNA methylation-based technology, in the early detection and localization of six types of cancers in the colorectum, esophagus, liver, lung, ovary and pancreas.

PATIENTS AND METHODS

A customized panel of 161,984 CpG sites was constructed and validated by public and in-house (cancer: n=249; non-cancer: n=288) methylome data, respectively. The cfDNA samples from 1,693 participants (cancer: n=735; non-cancer: n=958) were retrospectively collected to train and validate two multi-cancer detection blood test models (MCDBT-1/2) for different clinical scenarios. The models were validated on a prospective and independent cohort of age-matched 1,010 participants (cancer: n=505; non-cancer: n=505). Simulation using the cancer incidence in China was applied to infer stage-shift and survival benefits to demonstrate the potential utility of the models in the real world.

RESULTS

MCDBT-1 yielded a sensitivity of 69.1% (64.8%‒73.3%), a specificity of 98.9% (97.6%‒99.7%) and tissue origin accuracy of 83.2% (78.7%‒87.1%) in the independent validation set. For early stage (I‒III) patients, the sensitivity of MCDBT-1 was 59.8% (54.4%‒65.0%). In the real-world simulation, MCDBT-1 achieved the sensitivity of 70.6% in detecting the six cancers, thus decreasing late-stage incidence by 38.7%‒46.4%, and increasing 5-year survival rate by 33.1%‒40.4%, respectively. In parallel, MCDBT-2 was generated at a slightly low specificity of 95.1% (92.8%-96.9%) but a higher sensitivity of 75.1% (71.9%-79.8%) than MCDBT-1 for populations at relatively high risk of cancers, and also had ideal performance.

CONCLUSION

In this large-scale clinical validation study, MCDBT-1/2 models showed a high sensitivity, specificity, and accuracy of predicted origin in detecting six types of cancers.

Echocardiographic features of left ventricular dysfunction and outcomes in chronic kidney disease

OBJECTIVE

Heart failure (HF) imposes a substantial burden and the prevalence of HF is high in patients with chronic kidney disease (CKD). HF results in multiple hospital admissions, but whether HF subtypes worsen long-term outcomes and renal function in patients with CKD remains inconclusive.

METHODS

The study comprised 10 904 patients with CKD aged ≥20 years who underwent echocardiography between 1 January 2011 and 31 December 2018. The patients were stratified into four groups: non-HF, HF with reduced ejection fraction (HFrEF), HF with mildly reduced ejection fraction (HFmrEF) and HF with preserved ejection fraction (HFpEF). The primary end points were all-cause mortality, major adverse cardiovascular events (MACEs) and adverse renal outcomes.

RESULTS

In inverse probability of treatment weighting-adjusted method, the risk of all-cause mortality and MACEs relative to the non-HF group was greatest in the HFrEF group (HR 3.18 (95% CI 2.57 to 3.93) and HR 3.83 (95% CI 3.20 to 4.59)), followed by the HFmrEF (HR 2.75 (95% CI 2.22 to 3.42) and HR 3.08 (95% CI 2.57 to 3.69)) and HFpEF (HR 1.85 (95% CI 1.59 to 2.15) and HR 2.43 (95% CI 2.16 to 2.73) groups. In addition, the HFrEF group had the greatest risks of end-stage renal disease (HR 2.58 (95% CI 1.94 to 3.44)) compared with other groups.

CONCLUSIONS

HF is associated with subsequent worse clinical outcomes, which may be more pronounced in patients with HFrEF, followed by those with HFmrEF and those with HFpEF relative to non-HF group.

[Clinical epidemiological survey of primary liver cancer in Yunnan province from 2005 to 2014]

Objective: To investigate the clinical characteristics and changing trends of primary liver cancer in Yunnan province from 2005 to 2014, in order to provide theoretical basis for the prevention and treatment of liver cancer in this region. Methods: A retrospective survey was used to select inpatient cases of liver cancer who were initially diagnosed and treated in our hospital from 2005 to 2014 with simple random sampling. Patients socio-demographic and clinicopathological characteristics were extracted by a unified and standardized questionnaire, and the data were statistically analyzed. Results: A total of 1000 cases with liver cancer were included, aged (53.2±11.2) years, with a male-to-female ratio of 5.99/1.00. There was no significant change in the gender and age composition ratio of patients in the past 10 years. The proportion of patients with lower education level (primary or junior high school) were increased from 21.8% to 23.4%, and the proportion of patients with relatively higher education level were decreased from 58% to 38.2% (P<0.001). Smokers and non-smokers patients were decreased and increased from 58.8% to 44.4%, and 41.2% to 55.6% (P<0.001). The proportion of drinker patients were decreased from 46.4% to 35.2%. The proportion of patients with advanced liver cancer (stage C and D) were increased, while the proportion of patients with stage A and B showed a downward trend (P<0.001). The proportion of HBsAg-positive patients showed an upward trend, that is, rising from 69% in 2005 to 82% in 2014 (P=0.043). The proportion of HBeAg-positive patients showed a steady trend (P=0.008). The use rate of ultrasound examination in patients with liver cancer were decreased from 91.0% to 58.0% (P=0.001), while the use rate of computed tomography (CT), MRI, and PET/CT examinations were increased from 81.0% to 84.0% (P=0.05), 0 to 22% (P<0.001), and 0 to 3% (P=0.026) between 2005 to 2014. The proportion of surgical patients were increased (P=0.005), but the proportion of interventional patients did not change significantly (P=0.590). Surgery and interventional therapy were the most common treatment methods, and the proportion of patients treated with surgery over the past 10 years showed an upward trend (P=0.005), while the proportion of interventional therapy remained at a high level with no significant change (P=0.590). Conclusion: In Yunnan province, the incidence of liver cancer increases with age, and the proportion of male with liver cancer is almost six times that of women. Moreover, the low positive rate of alpha-fetoprotein levels and advanced clinical stage in this region are presently the main challenges against the liver cancer prevention and treatment. The application scope of CT, magnetic resonance imaging, PET-CT and other examination methods has gradually expanded, but the treatment methods are still mainly surgery and interventional therapy.

Urinary Galectin-3 as a Novel Biomarker for the Prediction of Renal Fibrosis and Kidney Disease Progression

Plasma galectin-3 (Gal-3) is associated with organ fibrosis, but whether urinary Gal-3 is a potential biomarker of kidney disease progression has never been explored. Between 2018 and 2021, we prospectively enrolled 280 patients who underwent renal biopsy and were divided into three groups based on their urinary Gal-3 levels (<354.6, 354.6−510.7, and ≥510.8 pg/mL) to assess kidney disease progression (defined as ≥40% decline in the estimated glomerular filtration rate or end-stage renal disease) and renal histology findings. Patients in the highest urinary Gal-3 tertile had the lowest eGFRs and highest proteinuria levels. In multivariate Cox regression models, patients in the highest tertile had the highest risk of kidney disease progression (adjusted hazard ratio, 4.60; 95% confidence interval, 2.85−7.71) compared to those in the lowest tertile. Higher urinary Gal-3 levels were associated with more severe renal fibrosis. Intrarenal mRNA expression of LGALS3 (Gal-3-encoded gene) was most correlated with the renal stress biomarkers (IGFBP7 and TIMB2), renal function biomarkers (PTGDS) and fibrosis-associated genes (TGFB1). The urinary Gal-3 level may be useful for the identification of patients at high risk of kidney disease progression and renal fibrosis, and for the early initiation of treatments for these patients.

Artificial Intelligence for Risk Prediction of End-Stage Renal Disease in Sepsis Survivors with Chronic Kidney Disease

Sepsis may lead to kidney function decline in patients with chronic kidney disease (CKD), and the deleterious effect may persist in patients who survive sepsis. We used a machine learning approach to predict the risk of end-stage renal disease (ESRD) in sepsis survivors. A total of 11,661 sepsis survivors were identified from a single-center database of 112,628 CKD patients between 2010 and 2018. During a median follow-up of 3.5 years, a total of 1366 (11.7%) sepsis survivors developed ESRD after hospital discharge. We adopted the random forest, extra trees, extreme gradient boosting, light gradient boosting machine (LGBM), and gradient boosting decision tree (GBDT) algorithms to predict the risk of ESRD development among these patients. GBDT yielded the highest area under the receiver operating characteristic curve of 0.879, followed by LGBM (0.868), and extra trees (0.865). The GBDT model revealed the strong effect of estimated glomerular filtration rates <25 mL/min/1.73 m2 at discharge in predicting ESRD development. In addition, hemoglobin and proteinuria were also essential predictors. Based on a large-scale dataset, we established a machine learning model computing the risk for ESRD occurrence among sepsis survivors with CKD. External validation is required to evaluate the generalizability of this model.

Identification of Galectin-3 as Potential Biomarkers for Renal Fibrosis by RNA-Sequencing and Clinicopathologic Findings of Kidney Biopsy

Background: Galectin-3 (Gal-3) is a multifunctional glycan-binding protein shown to be linked to chronic inflammation and fibrogenesis. Plasma Gal-3 is associated with proteinuria and renal dysfunction, but its role has never been confirmed with kidney biopsy results. In our study, we aimed to explore the expression of Gal-3 in biopsy-proven patients, and we tested the hypothesis that chronic kidney disease (CKD) leads to upregulation of plasma Gal-3 expression in corresponding biopsy findings and RNA sequencing analysis. Method: In 249 patients (male/female: 155/94, age: 57.2 ± 16.3 years) who underwent kidney biopsy, plasma levels of Gal-3 were measured to estimate the association of renal fibrosis. Relationships between plasma Gal-3 levels, estimated glomerular filtration rate (eGFR) and renal histology findings were also assessed. We further examined the gene expression of Gal-3 in RNA-sequencing analysis in biopsy-proven patients. Results: Compared to patients without CKD, CKD patients had higher levels of plasma Gal-3 (1,016.3 ± 628.1 pg/mL vs. 811.6 ± 369.6 pg/ml; P = 0.010). Plasma Gal-3 was inversely correlated with eGFR (P = 0.005) but not with proteinuria. Higher Gal-3 levels were associated with interstitial fibrosis, tubular atrophy and vascular intimal fibrosis. RNA-sequencing analysis showed the upregulation of Gal-3 in fibrotic kidney biopsy samples, and the differentially expressed genes were mainly enhanced in immune cell activation and the regulation of cell-cell adhesion. Conclusions: Plasma Gal-3 levels are inverse correlated with eGFR but positively correlated with renal fibrosis, which may be involved in the immune response and associated pathways. These findings support the role of Gal-3 as a predictive marker of renal fibrosis.

Antithrombotic Therapy for Chronic Kidney Disease Patients With Concomitant Atrial Fibrillation and Coronary Artery Disease

Background: Oral anticoagulants (OAC) plus antiplatelets is recommended for patients with atrial fibrillation (AF) and coronary artery disease (CAD) to reduce thromboembolism. However, there is limited evidence regarding antithrombotic therapy for patients with concomitant chronic kidney disease (CKD), AF, and CAD, especially those not undergoing percutaneous coronary intervention. We aimed to use real-world data assessing the efficacy and safety of antithrombotic regimens in this population.

Methods: We used a single-center database of 142,624 CKD patients to identify those receiving antithrombotic therapy for AF and CAD between 2010 and 2018. Patients taking warfarin or direct OAC (DOAC) alone were grouped in the OAC monotherapy (n = 537), whereas those taking OAC plus antiplatelets were grouped in the combination therapy (n = 2,391). We conducted propensity score matching to balance baseline covariates. The endpoints were all-cause mortality, major adverse cardiovascular events, and major bleedings.

Results: After 1:4 matching, the number of patients in OAC monotherapy and combination therapy were 413 and 1,652, respectively. Between the two groups, combination therapy was associated with higher risks for ischemic stroke (HR 2.37, CI 1.72–3.27), acute myocardial infarction (HR 6.14, CI 2.51–15.0), and hemorrhagic stroke (HR 3.57, CI 1.35–9.81). The results were consistent across CKD stages. In monotherapy, DOAC users were associated with lower risks for all-cause mortality, AMI, and gastrointestinal bleeding than warfarin, but the stroke risk was similar between the two subgroups.

Conclusions: For patients with concomitant CKD, AF and CAD not undergoing PCI, OAC monotherapy may reduce stroke and AMI risks. DOAC showed more favorable outcomes than warfarin.

Dose-response effects of physical activity on all-cause mortality and major cardiorenal outcomes in chronic kidney disease

AIMS

Physical activity has a protective effect against mortality and cardiovascular events in chronic kidney disease (CKD) patients. Nonetheless, how different levels of physical activity affect the health benefits in CKD remains unclear. This study aimed to investigate the dose-response effects of physical activity on mortality and major cardiorenal events in CKD.

METHODS AND RESULTS

We evaluated a longitudinal cohort of 4508 Taiwanese CKD patients between 2004 and 2017. Physical activity was assessed by the NHANES questionnaire and quantified in metabolic equivalent-hours per week (MET-hour/week). Patients were categorized into highly active (≥7.5 MET-h/week), low-active (0.1 to <7.5 MET-h/week), or inactive (0 MET-h/week) groups. Cox regression and restricted cubic spline models were utilized to explore the association between physical activity and the risks of study outcomes, including all-cause mortality, end-stage renal disease (ESRD), and major adverse cardiovascular events (MACE, a composite of cardiovascular death, myocardial infarction, ischaemic stroke, and hospitalized heart failure). During a median follow-up of 686 days, 739 death, 1059 ESRD, and 521 MACE events occurred. Highly active group had the lowest chance of all study outcomes, followed by low-active and inactive groups (P < 0.001). Multivariable Cox regression showed that only highly active group was independently associated with lower risks for all-cause mortality [hazard ratio (HR) 0.62; 95% confidence interval (CI) 0.53-0.74], ESRD (HR 0.83, 95% CI 0.72-0.96), and MACE (HR 0.63, 95% CI 0.51-0.76) compared to the inactive group. The risks of MACE did not further decrease once physical activity surpassed 15 MET-h/week, indicating a U-shaped association. The results were consistent in the subgroup and sensitivity analyses.

CONCLUSION

Physical activity of 7.5 to <15 MET-h/week is associated with lower risks of adverse cardiorenal outcomes and should be integrated into the care of CKD.

[Analysis of EGFR mutation and clinical features of lung cancer in Yunnan]

Objective: To analyze the EGFR mutation profile of lung cancer patients in Yunnan, and to provide evidence for clinical personalized treatment. Methods: Demographic and clinical data of 2 967 lung cancer patients undergoing EGFR identification were collected and analyzed from January 2014 to August 2019 in Yunnan Cancer Hospital. Results: The proportion of EGFR mutation in 2 967 patients with lung cancer was 46.2%. Univariate analysis showed that the proportion of EGFR mutation in women was higher than that in men (P<0.001) and displayed a downward trend with age (P=0.03). The mutation rate of ethnic minorities was higher than Han (P=0.012). Mutation rate in patients without smoking history was higher than those with smoking history (P<0.001), and patients without drinking history was higher than patients with drinking history (P<0.001). Mutation rate in patients without family history of lung cancer was higher than those with family history (P=0.008). The mutation rate of adenocarcinoma was higher than other pathological types (P<0.001). The mutation rate was different among stages, and it was higher in early patients than that in advanced patients (P<0.001). The mutation rate of tissue specimens was higher than those of cytology and peripheral blood samples (P<0.001). The mutation rate of Xuanwei area was lower than that in non-Xuanwei area (P<0.001). Multivariate analysis showed that gender (P<0.001), age (P=0.036), smoking history (P<0.001), pathological type (P<0.001), specimen type (P<0.001), and whether or not Xuanwei area (P<0.001) were the independent factors of EGFR mutation.The EGFR mutation was more common in female, non-smokers, adenocarcinoma, non-Xuanwei area, tissue specimen and young lung cancer patients.The mutation types of EGFR in 1 370 cases mainly included 19-Del and L858R. The predominant mutation of EGFR in Xuanwei area was L858R, while in non-Xuanwei area was 19-Del.The mutation rates of G719X, G719X+ L861Q, G719X+ S768I, and S768I in Xuanwei were higher while the mutation rates of 19-Del, L858R, and 20-ins were lower than non-Xuanwei area (P<0.05). The 19-Del mutation rate of ethnic minorities is higher than that of Han (P<0.001). The combined mutation rate of G719X, L861Q in Han was higher than that of ethnic minorities (P=0.005). Conclusions: The EGFR mutation rate in lung cancer patients in Yunnan is similar to Asian and Chinese, and higher in female, non-smokers, adenocarcinomas, young and non-Xuanwei area patients. The most common types of EGFR mutation in Yunnan are 19-Del and L858R. The predominant mutation of EGFR in Xuanwei area is L858R, while in non-Xuanwei area is 19-Del. The mutation rates of G719X, G719X+ L861Q, G719X+ S768I and S768I are higher in Xuanwei patients than those in non-Xuanwei patients. The combined mutation rate of G719X and L861Q in Han nationality is higher than that of ethnic minorities.

The Anastomotic Angle of Hemodialysis Arteriovenous Fistula Is Associated With Flow Disturbance at the Venous Stenosis Location on Angiography

The juxta-anastomotic stenosis of an arteriovenous fistula (AVF) is a significant clinical problem in hemodialysis patients with no effective treatment. Previous studies of AV anastomotic angles on hemodynamics and vascular wall injury were based on computational fluid dynamics (CFD) simulations using standardized AVF geometry, not the real-world patient images. The present study is the first CFD study to use angiographic images with patient-specific outcome information, i.e., the exact location of the AVF stenotic lesion. We conducted the CFD analysis utilizing patient-specific AVF geometric models to investigate hemodynamic parameters at different locations of an AVF, and the association between hemodynamic parameters and the anastomotic angle, particularly at the stenotic location. We analyzed 27 patients who used radio-cephalic AVF for hemodialysis and received an angiographic examination for juxta-anastomotic stenosis. The three-dimensional geometrical model of each patient's AVF was built using the angiographic images, in which the shape and the anastomotic angle of the AVF were depicted. CFD simulations of AVF hemodynamics were conducted to obtain blood flow parameters at different locations of an AVF. We found that at the location of the stenotic lesion, the AV angle was significantly correlated with access flow disturbance (r = 0.739; p < 0.001) and flow velocity (r = 0.563; p = 0.002). Furthermore, the receiver operating characteristic (ROC) curve analysis revealed that the AV angle determines the lesion's flow disturbance with a high area under the curve value of 0.878. The ROC analysis also identified a cut-off value of the AV angle as 46.5°, above or below which the access flow disturbance was significantly different. By applying CFD analysis to real-world patient images, the present study provides evidence that an anastomotic angle wider than 46.5° might lead to disturbed flow generation, demonstrating a reference angle to adopt during the anastomosis surgery.

Absence of Modulating Effects of Cytokines on Antioxidant Enzymes in Peritoneal Mesothelial Cells

Objective

To investigate the modulation of superoxide dismutase, glutathione peroxidase, and catalase by cytokines and endotoxin in human peritoneal mesothelial cells.

Design

Cultured human peritoneal mesothelial cells were treated with various concentrations of interleu kin-1 α, tumor necrosis factor-α(TNFα), interleukin-6, interleukin-8, transforming growth factor-β (TGFβ), and lipopolysaccharide. Cell morphology was observed and the activities of superoxide dismutase, catalase, and glutathione peroxidase were assayed. The antioxidant enzyme activities of human peritoneal mesothelial cells were also compared with those of human liver and kidney tissues.

Results

Interleukin-1α, TNFα, TGFβ, and lipopolysaccharide caused dose-dependent cytotoxicities in mesothelial cells. The activities of these three antioxidant enzymes did not change after treatment with cytokines and endotoxin. The total superoxide dismutase activity of confluent human peritoneal mesothelial cells was found to be greater than that of human liver and kidney tissues and was composed mostly of manganese superoxide dismutase activity. Furthermore, glutathione peroxidase and catalase activities of human peritoneal mesothelial cells were lower than those of human liver and kidney tissues.

Conclusion

In human peritoneal mesothelial cells, lack of induction of antioxidant enzymes by inflammatory cytokines, as well as high superoxide dismutase activity accompanied by insufficient glutathione peroxidase and catalase activities may both contribute to the susceptibility of these cells to oxidative damage. Therefore, appropriate management to decrease oxidative injury to the peritoneum should be taken into consideration when treating long-term continuous ambulatory peritoneal dialysis patients.

[Analysis of colorectal cancer screening results in Kunming from 2014 to 2017]

This study analyzed the distribution of high-risk population, the compliance and detected lesions of colorectal cancer screening from the Cancer Screening Program in urban areas of Kunming,Yunnan Province from 2014 to 2017. A total of 127 960 residents were included,of which 14 791 (11.70%) cases were diagnosed with high risk of colorectal cancer by the National Cancer Center High Risk Population Assessment System. A total of 3 484 cases completed colonoscopy clinical screening and the rate of participation was 23.55%. The screening results showed that 592 positive cases were detected, and the positive rate was 17.17%. The detection rates of polyps,adenomas,advanced adenomas,precancerous lesions and colorectal cancer were 16.27%,13.12%,7.18%,7.63% and 0.26%, with 567, 457, 250, 266 and 9 cases, respectively.

Increased Nighttime Pulse Pressure Variability but Not Ambulatory Blood Pressure Levels Predicts 14-Year All-Cause Mortality in Patients on Hemodialysis

Increased short-term blood pressure (BP) variability is associated with adverse cardiovascular outcomes in patients with hypertension. The present study investigated the long-term prognostic significance of the short-term blood pressure variability in patients on hemodialysis. A total of 149 patients (53.0% male; mean age: 54.5±15.1 years) receiving regular hemodialysis for >6 months were enrolled. They completed a 44-hour (excluding the hemodialysis session) ambulatory BP monitoring and comprehensive hemodynamic assessments, including carotid-femoral pulse wave velocity and pressure waveform decomposition (forward and backward wave amplitude). Blood pressure variability parameters, including average real variability (ARV) of systolic BP, diastolic BP, and pulse pressure (ARVp) during daytime, nighttime, and overall 44 hours were calculated. During a median follow-up of 14 years, 78 deaths (52.4%) were confirmed. In multivariable Cox regression analysis, none of the ambulatory BP parameters were predictive of mortality. In contrast, nighttime ARVp was consistently and significantly associated with all-cause mortality in multivariable Cox models adjusting for age, sex, albumin, hemodialysis treatment adequacy, and 44-hour systolic BP (continuous variable analysis, per 1-SD, hazard ratio=1.348; 95% CI, 1.029-1.767; categorical variable analysis, ≥8.5 versus <8.5 mm Hg; hazard ratio=1.825; 95% CI, 1.074-3.103). Forward wave amplitude and 44-hour systolic BP were identified as the 2 most important determinants of nighttime ARVp. Addition of nighttime ARVp to the base model significantly improved prediction of all-cause mortality (Net reclassification improvement =0.198; P=0.0012). In hemodialysis patients, increased short-term nighttime pulse pressure variability but not ambulatory BP levels were significantly predictive of long-term all-cause mortality.

Tissue Doppler imaging predicts outcomes in hemodialysis patients with preserved left ventricular function

BACKGROUND

Cardiovascular disease is a major cause of mortality in patients with end-stage renal disease (ESRD). In addition to arteriosclerosis (arterial stiffness) and atherosclerosis, left ventricular (LV) hypertrophy and LV systolic dysfunction are the major cardiac determinants of cardiovascular mortality in hemodialysis patients. Although LV diastolic dysfunction is common in patients with ESRD, its prognostic value is yet to be established.

METHODS

A total of 103 ESRD patients (52 females, 51 males, age 51 ± 14 years) receiving regular hemodialysis and with preserved LV systolic function were prospectively enrolled in the current study. A comprehensive cardiovascular evaluation was performed at baseline. LV diastolic function was assessed using Doppler mitral inflow velocity and tissue Doppler imaging (TDI) of the mitral annulus velocity. Predictors for hospitalization and all-cause mortality were identified via Cox proportional hazards analysis.

RESULTS

There were 20 deaths and 46 hospitalizations during a follow-up period of 67.9 ± 20.2 months. After adjusting for age, aortic pulse wave velocity (PWV), and carotid intima media thickness, Cox analysis demonstrated that ratio of early ventricular filling velocity (E) to early diastolic tissue velocity mitral annulus (E') (E/E') was a significant predictor for hospitalization (hazard ratio [HR] 1.235 and 95% CI 1.115-1.368 per-1SD). E' also independently predicted mortality (HR 0.682, 95% CI 0.472-0.985). The TDI parameters significantly correlated with the LV mass index and PWV.

CONCLUSION

The findings of the current study suggest that diastolic function, as indexed by TDI, is an independent predictor of hospitalization and mortality in ESRD patients receiving regular hemodialysis and with preserved LV systolic function. The TDI parameters may reflect the impairment of arterial function and LV pressure overload.

Hyperuricemia Predicts an Early Decline in Renal Function among Older People: A Community-Based Cohort Study

Whether elevated serum uric acid levels (SUA) predict renal dysfunction remains controversial in the elderly. Therefore, we investigated the association between SUA and early renal function decline defined as an estimated glomerular filtration rate (eGFR) reduction ≥30% over 2 years. From 2001 to 2010, we conducted a longitudinal cohort study comprising 44,078 participants aged ≥65 years in the Taipei City Elderly Health Examination Database. Participants were classified by 1-mg/dL increment of SUA. We used multivariable logistic and Cox regression analyses to compare the risk of early renal function decline in different SUA groups. Compared to the reference SUA group of 5.0–5.9 mg/dL, hyperuricemic participants had increased risks of eGFR decline, starting at SUA ≥6.0 mg/dL (adjusted odds ratio [aOR] = 1.21, 95% confidence interval [CI] = 1.00–1.45). The risk progressively elevated as SUA increased, with the highest in the SUA ≥10.0 mg/dL group (aOR = 3.20, CI = 2.39–4.28). Multivariable Cox regression further confirmed that hyperuricemia was 1.12-fold (CI = 1.03–1.22, SUA ≥6.0 mg/dL) to 1.6-fold (CI = 1.37–1.86, SUA ≥10.0 mg/dL) more likely to develop early eGFR decline. Hyperuricemia-associated increased risks for early eGFR decline were consistent across subgroup and sensitivity analyses. Collectively, SUA ≥6.0 mg/dL independently predicted early renal dysfunction with eGFR decline ≥30% over 2 years in older people.

[Clinical outcomes of cervical disc herniation treated by posterior percutaneous endoscopic cervical discectomy]

Objective: To evaluate the clinical outcomes of posterior percutaneous endoscopic cervical discectomy (PPECD) for cervical disc herniation. Methods: A total of 23 patients who underwent PPECD for cervical disc herniation at Department of Spine Surgery, Guangdong Provincial Hospital of Chinese Medicine from August 2014 to April 2016 were reviewed. The mean age of the 17 males and 6 females was 49.5 years (range from 31 to 61 years). All patients had unilateral upper limb radiating symptoms, 13 patients with right upper limb radiating pain and 10 patients with left upper limb radiation pain, 17 patients with neck pain symptoms. Responsible segment: left C(4-5) 1 case, right C(4-5) 2 cases, left C(5-6) 4 cases, right C(5-6) 8 cases, left C(6-7) 5 cases, right C(6-7) 3 example.Operating time, length of hospitalization, complications, neck and arm Visual analog scale(VAS), and Neck Disability Index(NDI) were evaluated. The excellent and good rate of surgery was evaluated by using the Odom criteria. Harrison method was used to measure cervical curvature. The Cobb angle of the surgical segment was measured on the X-ray, and the range of motion (ROM) was calculated. The changes of the cervical curvature and the surgical segment ROM were compared pre- and post-operation. Results: The operation time was 94.1 min (range from 80 to 150 min). The average length of hospital stay was 4.8 days. The mean follow-up period was 23.5 months (range from 15 to 35 months). The preoperative arm VAS score was 6.95±0.88, 1-week postoperative arm VAS score was 2.09±0.67, the last follow-up arm VAS score was 1.04±0.98. The preoperative neck VAS score was 3.04±0.77, 1-week postoperative neck VAS score was 1.52±0.51 and the last follow-up neck VAS score was 0.61±0.78. The 1-week postoperative and last follow-up arm and neck VAS scores were significantly reduced compared with pre-operation (P<0.01). Compared with 1 week after surgery, the last follow-up of the arm and neck VAS score further reduced, the difference was statistically significant (P<0.01). The preoperative NDI was (58.52±4.98)%, the 1-week postoperative NDI was (33.74±4.72)%, the last follow-up NDI was (19.22±3.23)%. The 1-week postoperative and last follow-up NDI was significantly improved compared with pre-operation (P<0.01). Compared with 1 week after surgery, the last follow-up of the NDI further improved, the difference was statistically significant (P<0.01). The 1-week postoperative cervical curvature was (14.65±2.89)°, and it was improved compared with preoperative(14.23±3.06)°, the difference was statistically significant (P<0.05) . The last follow-up was cervical curvature(14.64±2.68)°, there was no significant difference compared with preoperative (P> 0.05). The preoperative surgical ROM was(5.37±1.83)°, 1-week postoperative was(5.53±1.52)°, and the last follow-up was (5.62±1.48)°, there was no significant difference pre-operative and post-operation (P> 0.05). The excellent and good rate was 91.3% (excellent in 16 cases, good in 5 cases, 2 cases). There was no nerve root injury, cerebrospinal fluid leakage, wound infection, and other complications. Conclusions: PPECD is a sufficient and safe supplement for cervical disc herniation, its recent clinical efficacy was good. And it has no significant effect on cervical stability.

Value of Excess Pressure Integral for Predicting 15-Year All-Cause and Cardiovascular Mortalities in End-Stage Renal Disease Patients

BACKGROUND

The excess pressure integral (XSPI), derived from analysis of the arterial pressure curve, may be a significant predictor of cardiovascular events in high-risk patients. We comprehensively investigated the prognostic value of XSPI for predicting long-term mortality in end-stage renal disease patients undergoing regular hemodialysis.

METHODS AND RESULTS

A total of 267 uremic patients (50.2% female; mean age 54.2±14.9 years) receiving regular hemodialysis for more than 6 months were enrolled. Cardiovascular parameters were obtained by echocardiography and applanation tonometry. Calibrated carotid arterial pressure waveforms were analyzed according to the wave-transmission and reservoir-wave theories. Multivariable Cox proportional hazard models were constructed to account for age, sex, diabetes mellitus, albumin, body mass index, and hemodialysis treatment adequacy. Incremental utility of the parameters to risk stratification was assessed by net reclassification improvement. During a median follow-up of 15.3 years, 124 deaths (46.4%) incurred. Baseline XSPI was significantly predictive of all-cause (hazard ratio per 1 SD 1.4, 95% confidence interval 1.15-1.70, P=0.0006) and cardiovascular mortalities (1.47, 1.18-1.84, P=0.0006) after accounting for the covariates. The addition of XSPI to the base prognostic model significantly improved prediction of both all-cause mortality (net reclassification improvement=0.1549, P=0.0012) and cardiovascular mortality (net reclassification improvement=0.1535, P=0.0033). XSPI was superior to carotid-pulse wave velocity, forward and backward wave amplitudes, and left ventricular ejection fraction in consideration of overall independent and incremental prognostics values.

CONCLUSIONS

In end-stage renal disease patients undergoing regular hemodialysis, XSPI was significantly predictive of long-term mortality and demonstrated an incremental value to conventional prognostic factors.

Association of warfarin with congestive heart failure and peripheral artery occlusive disease in hemodialysis patients with atrial fibrillation

BACKGROUND

The effect of warfarin on the risk of cardiovascular (CV) disease is unknown among chronic hemodialysis patients with atrial fibrillation (HD-AF).

METHODS

Population-based propensity score and prescription time-distribution matched cohort study including 6719 HD-AF patients with CHA₂DS₂-VASc score ≥ 2 were divided into warfarin users and nonusers and followed-up for CV events and death.

RESULTS

Warfarin treatment in HD-AF patients with AF preceding HD was associated with higher risks of developing congestive heart failure [hazard ratio (HR)=1.82, 95% confidence interval (CI)=1.29-2.58, p<0.01], peripheral artery occlusive disease (HR=3.42, 95% CI=1.86-6.31, p<0.01), and aortic valve stenosis (HR=3.20, 95% CI=1.02-9.98, p<0.05). Warfarin users were not associated with risks of ischemic or hemorrhagic stroke and all-cause mortality as compared to nonusers.

CONCLUSION

Warfarin may be associated with vascular calcification, increasing the risks of congestive heart failure and peripheral artery occlusive disease among HD-AF patients.

High Uric Acid Ameliorates Indoxyl Sulfate-Induced Endothelial Dysfunction and Is Associated with Lower Mortality among Hemodialysis Patients

High uric acid (UA) can act as a pro-oxidant in normal physiological conditions; however, emerging evidence is still debatable with regard to the association between high UA and poor outcomes among chronic hemodialysis (HD) patients. In the present study, 27,229 stable prevalent HD patients were enrolled and divided into four groups according to the quartiles of baseline UA concentration, and 5737 died during a median follow-up of 38 months. Multivariate Cox regression analysis showed that a UA level of <6.1 mg/dL was associated with a higher risk of all-cause mortality compared with a UA level of >8.1 mg/dL [HR, 1.20, 95% CI (1.10–1.31)] adjusting for baseline demographic and biochemical parameters. Moreover, a UA level of <6.1 mg/dL was associated with greater risks of cardiovascular mortality [HR, 1.26, 95% CI (1.13–1.41)] and stroke-related mortality [HR, 1.59, 95% CI (1.12–2.25)], respectively. In vitro experiments further showed an increase in oxidative stress and an inhibition nitric oxide synthesis by indoxyl sulfate (IS) in human aortic endothelial cells, which were significantly attenuated by UA in a dose-dependent manner. We concluded that higher UA in serum was associated with lower risk of all-cause and cardiovascular mortality among HD patients probably through its antioxidant property in ameliorating the IS-related vascular toxicity.

Comparative proteomic analysis of rat left ventricle in a subtotal nephrectomy model

BACKGROUND

Chronic kidney disease (CKD) is associated with cardiac hypertrophy that leads to increased cardiovascular morbidity and mortality. To date, use of the renin-angiotensin-aldosterone system blockade has been the main treatment modality. However, renin-angiotensin-aldosterone system blockade by the angiotensin converting enzyme inhibitors (ACEi) can only partially reverse the cardiac hypertrophy without having a significant impact on all-cause mortality as evidenced by meta-analyses from clinical trials. It is imperative to elucidate the molecular pathogenesis of CKD-related cardiomyopathy for potential targets in further treatment.

METHODS

Male Sprague-Dawley rats that underwent subtotal nephrectomy (SNX) rats were established as the CKD model. A hemodynamic study was used to evaluate the left ventricle (LV) structural and functional alterations. We used proteomic techniques to profile the LV protein changes among sham-operated rats, SNX rats, and SNX rats with 6 months of ACEi enalapril interventions. The differentially expressed proteins were further annotated by functional and network analyses.

RESULTS

As compared to the sham-operated rats, the SNX rats had 25 upregulated and 46 decreased protein expression. The top canonical pathways identified by ingenuity pathway analysis for the CKD cardiomyopathy were mitochondrial dysfunction, oxidative phosphorylation, fatty acid β oxidation, protein ubiquitination, and ketolysis. The most relevant functions extracted from these networks contained 27 and 23 focused proteins, respectively. They were related to cellular assembly and organization, RNA posttranscriptional modification, and protein synthesis. After ACEi intervention for 6 weeks, the residual canonical pathways identified by ingenuity pathway analysis that mediated the CKD-related cardiomyopathy were mitochondrial dysfunction, ketolysis, phenylalanine degradation IV, and putrescine degradation III. There were decreased Sirt3 and SNRNP, and increased monoamine oxidase and SAHH expression in the LV of SNX rats that could not be reversed by the ACEi.

CONCLUSION

Our studies provide a repertoire of potential biomarkers related to cardiac hypertrophy in CKD. There are still residual disturbed molecules/pathways despite ACEi intervention. Further studies are warranted to investigate these potential novel targets to alleviate CKD-related cardiomyopathy.

Erythropoiesis-stimulating agents in chronic kidney disease: what have we learned in 25 years?

Since the pioneering studies by Eschbach et al in 1987, erythropoiesis-stimulating agents (ESAs) have become the mainstay of anemia therapy in chronic kidney disease (CKD) patients. The introduction of ESAs 25 years ago markedly improved the lives of many patients with CKD, who until then had severe, often transfusion-dependent anemia. However, randomized controlled trials demonstrate an increased risk for cardiovascular events such as stroke, thrombosis, and death at nearly normal hemoglobin concentrations and higher ESA doses in CKD. By contrast, kidney transplant recipients may represent a unique population of CKD patients who may benefit from ESA therapy. This review discusses potential mechanisms involving the erythropoietic and nonerythropoietic effects of ESA treatment and ESA resistance. Further research aimed at elucidating the causal pathways is strongly recommended. Given current knowledge, however, clinical practice should avoid disproportionately high dosages of ESAs to achieve recommended hemoglobin targets, particularly in those with significant cardiovascular morbidity or ESA resistance. The key to CKD anemia management will be individualization of the potential benefits of reducing blood transfusions and anemia-related symptoms against the risks of harm.

Aldosterone and mortality in hemodialysis patients: role of volume overload

BACKGROUND

Elevated aldosterone is associated with increased mortality in the general population. In patients on dialysis, however, the association is reversed. This paradox may be explained by volume overload, which is associated with lower aldosterone and higher mortality.

METHODS

We evaluated the relationship between aldosterone and outcomes in a prospective cohort of 328 hemodialysis patients stratified by the presence or absence of volume overload (defined as extracellular water/total body water >48%, as measured with bioimpedance). Baseline plasma aldosterone was measured before dialysis and categorized as low (<140 pg/mL), middle (140 to 280 pg/mL) and high (>280 pg/mL).

RESULTS

Overall, 36% (n = 119) of the hemodialysis patients had evidence of volume overload. Baseline aldosterone was significantly lower in the presence of volume overload than in its absence. During a median follow-up of 54 months, 83 deaths and 70 cardiovascular events occurred. Cox multivariate analysis showed that by using the low aldosterone as the reference, high aldosterone was inversely associated with decreased hazard ratios for mortality (0.49; 95% confidence interval, 0.25-0.76) and first cardiovascular event (0.70; 95% confidence interval, 0.33-0.78) in the presence of volume overload. In contrast, high aldosterone was associated with an increased risk for mortality (1.97; 95% confidence interval, 1.69-3.75) and first cardiovascular event (2.01; 95% confidence interval, 1.28-4.15) in the absence of volume overload.

CONCLUSIONS

The inverse association of aldosterone with adverse outcomes in hemodialysis patients is due to the confounding effect of volume overload. These findings support treatment of hyperaldosteronemia in hemodialysis patients who have achieved strict volume control.

Intravenous ferric chloride hexahydrate supplementation induced endothelial dysfunction and increased cardiovascular risk among hemodialysis patients

Background

The association between intravenous (IV) iron administration and outcomes in hemodialysis (HD) patients is still debated. Therefore, this study was aimed to assess the relationship between the IV administration of ferric chloride hexahydrate (Atofen®) and cardiovascular (CV) outcome and the interaction between iron-induced oxidative stress and endothelial dysfunction in chronic HD patients.

Methodology/Principal Findings

A cohort of 1239 chronic HD patients was recruited. In a follow-up of 12 months, Kaplan-Meier survival curves showed that higher doses of IV Atofen associated with higher risks for CV events and deaths in HD patients. In multivariate Cox models, compared to no iron supplementation, IV Atofen administration was an independent predictor for CV events and overall mortality. However, the nature of the observational cohort study possibly bears selection bias. We further found that IV Atofen enhanced the superoxide production of mononuclear cells (MNCs), the levels of circulating soluble adhesion molecules, and the adhesion of MNCs to human aortic endothelial cells (HAECs). In vitro experiments showed that Atofen increased the expression of intracellular cell adhesion molecule-1 and vascular cell adhesion molecule-1 in HAECs and aggravated the endothelial adhesiveness in a dose-dependent manner. These iron-induced changes were significantly attenuated by the co-treatment of HAECs with N-acetylcysteine and inhibitors of NADPH oxidase, nuclear factor κB, and activator protein-1.

Conclusion

A cumulative dose of IV Atofen >800 mg within 6 months was associated with an adverse CV outcome and a higher mortality among chronic HD patients. The detrimental effects of IV iron supplementation were partly due to the increased oxidative stress and induction of MNC adhesion to endothelial cells, a pivotal index of early atherogenesis.

Cardiovascular determinants of prognosis in normotensive hemodialysis patients

Background

Normotension has been hold to be the goal of hemodialysis. It remains obscure which cardiovascular parameter determines the prognosis in these normotensive hemodialysis patients.

Methods

We prospectively enrolled 145 hemodialysis patients, who had attained normotension without anti-hypertensive medications, and followed them for 72.6 ± 28.5 months. Important cardiovascular parameters were obtained at enrollment. Predictors for all-cause and cardiovascular mortalities were identified with the Cox model.

Results

There were 45 (18 cardiovascular/27 non-cardiovascular) deaths occurred during follow-up. Age, diabetes, left ventricular mass index (LVMI), left ventricular ejection fraction (LVEF), carotid intima-media thickness (CIMT), and aortic pulse wave velocity (PWV) were significant predictors for all-cause and cardiovascular mortalities. After adjustment for age and diabetes, only LVEF was significantly associated with all-cause mortality. LVEF was significantly associated with cardiovascular mortality. LVEF remained as a significant independent predictor of cardiovascular death after adjusting for age, diabetes, LVMI, CIMT, or PWV, respectively.

Conclusion

LVEF is the independent predictor for all-cause and cardiovascular mortalities in the normotensive hemodialysis patients.

Plasma protein characteristics of long-term hemodialysis survivors

Hemodialysis (HD) patients are under recurrent circulatory stress, and hemodialysis has a high mortality rate. The characteristics of plasma proteomes in patients surviving long-term HD remain obscure, as well as the potential biomarkers in predicting prognoses. This study reports the proteome analyses of patient plasma from non-diabetic long-term HD (LHD, dialysis vintage 14.9±4.1 years, n = 6) and the age/sex/uremic etiology-comparable short-term HD (SHD, dialysis vintage 5.3±2.9 years, n = 6) using 2-DE and mass spectrometry. In addition, a 4-year longitudinal follow-up of 60 non-diabetic HD patients was subsequently conducted to analyze the baseline plasma proteins by ELISA in predicting prognosis. Compared to the SHD, the LHD survivors had increased plasma vitamin D binding proteins (DBP) and decreased clusterin, apolipoprotein A-IV, haptoglobin, hemopexin, complement factors B and H, and altered isoforms of α1-antitrypsin and fibrinogen gamma. During the 45.7±15 months for follow-up of the 60 HD patient cases, 16 patients died. Kaplan-Meier analysis demonstrated that HD patients with the lowest tertile of the baseline plasma DBP level have a significantly higher mortality rate. Multivariate Cox regression analysis further indicated that DBP is an independent predictor of mortality. In summary, the altered plasma proteins in LHD implicated accelerated atherosclerosis, defective antioxidative activity, increased inflammation/infection, and organ dysfunction. Furthermore, lower baseline plasma DBP in HD patients is related to mortality. The results suggest that the proteomic approach could help discover the potential biomarker in HD prognoses.

Decoy receptor 3, a novel inflammatory marker, and mortality in hemodialysis patients

BACKGROUND AND OBJECTIVES

Inflammation is closely associated with cardiovascular disease, the leading cause of mortality in patients with CKD. Serum decoy receptor 3 (DcR3) is a member of the TNF receptor superfamily. CKD patients have higher levels of DcR3 than the general population, but whether DcR3 predicts mortality in CKD patients on hemodialysis has not been explored.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

DcR3 levels were measured in 316 prevalent hemodialysis patients who were followed up from November 1, 2004, to June 30, 2009, for cardiovascular and all-cause mortality.

RESULTS

The baseline DcR3 concentration showed a strong positive correlation with inflammatory markers including high-sensitivity C-reactive protein, IL-6, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1). During a follow-up period of 54 months, 90 patients died (34 cardiovascular deaths). Kaplan-Meier survival analysis showed higher cardiovascular and all-cause mortality in patients with higher DcR3 levels. The hazard ratios (95% confidence intervals) of the highest versus lowest tertiles of DcR3 were 2.8 (1.1-7.3; P for trend=0.04) for cardiovascular mortality and 2.1 (1.1-3.7; P for trend=0.02) for all-cause mortality, respectively. Based on the minimal increase in the area under the receiver operating characteristic curve from 0.79 to 0.80, the addition of DcR3 to established risk factors including VCAM-1, albumin, and IL-6 does not improve the prediction of mortality.

CONCLUSIONS

Higher DcR3 levels strongly correlate with inflammation and independently predict cardiovascular and all-cause mortality in CKD patients on hemodialysis.

Postdialysis blood pressure rise predicts long-term outcomes in chronic hemodialysis patients: a four-year prospective observational cohort study

BACKGROUND

The blood pressure (BP) of a proportion of chronic hemodialysis (HD) patients rises after HD. We investigated the influence of postdialysis BP rise on long-term outcomes.

METHODS

A total of 115 prevalent HD patients were enrolled. Because of the fluctuating nature of predialysis and postdialysis BP, systolic BP (SBP) and diastolic BP before and after HD were recorded from 25 consecutive HD sessions during a 2-month period. Patients were followed for 4 years or until death or withdrawal.

RESULTS

Kaplan-Meier estimates revealed that patients with average postdialysis SBP rise of more than 5 mmHg were at the highest risk of both cardiovascular and all-cause mortality as compared to those with an average postdialysis SBP change between -5 to 5 mmHg and those with an average postdialysis SBP drop of more than 5 mmHg. Furthermore, multivariate Cox regression analysis indicated that both postdialysis SBP rise of more than 5 mmHg (HR, 3.925 [95% CI, 1.410-10.846], p = 0.008) and high cardiothoracic (CT) ratio of more than 50% (HR, 7.560 [95% CI, 2.048-27.912], p = 0.002) independently predicted all-cause mortality. We also found that patients with an average postdialysis SBP rise were associated with subclinical volume overload, as evidenced by the significantly higher CT ratio (p = 0.008).

CONCLUSIONS

A postdialysis SBP rise in HD patients independently predicted 4-year cardiovascular and all-cause mortality. Considering postdialysis SBP rise was associated with higher CT ratio, intensive evaluation of cardiac and volume status should be performed in patients with postdialysis SBP rise.

Risk factors associated with elevated serum pancreatic amylase levels during hemodialysis

Elevated levels of serum pancreatic enzymes are frequently observed in hemodialysis (HD) patients. The complex hemodynamic, biochemical, and physiological alterations in uremia were speculated to cause excessive release of pancreatic enzymes beyond decreased renal clearance. However, hemodynamic factors are seldom explored in this aspect. We performed the study to evaluate the association between intradialytic hemodynamic change and elevated serum pancreatic amylase (SPA). Eighty-three prevalent HD patients without any clinical evidence of acute pancreatitis underwent pre-HD and post-HD blood sampling for serum pancreatic enzyme levels. Demographic, biochemical, and hematological data were collected from patient record review. Hemodialysis information including intradialytic blood pressure changes and ultrafiltration (UF) amount were collected and averaged for 1 month before the blood sampling day. Patients with elevated SPA during the HD session had greater mean systolic blood pressure and mean arterial pressure reduction, greater UF volume, greater pre-HD blood urea nitrogen and serum creatinine, higher serum phosphorus, lower pre-HD serum total CO2, and lower left ventricle ejection fraction (LVEF). Using multivariate linear and logistic regression analysis, the independent predictors of elevated SPA were determined to be mean arterial pressure reduction during HD, mean UF amount, pre-HD serum total CO2, and LVEF. Greater blood pressure reduction during HD, greater UF volume, lower pre-HD serum total CO2, and lower LVEF were significantly associated with elevated SPA during HD. This suggests that hemodynamic factors contribute to elevated serum pancreatic enzymes in HD patients.

A comparison of cystatin C- and creatinine-based prediction equations for the estimation of glomerular filtration rate in black South Africans

BACKGROUND

Serum creatinine (S-Cr)-based prediction equations are commonly used for estimating glomerular filtration rate (GFR). However, S-Cr concentration is also affected by other factors such as tubular secretion, muscle mass, diet, gender and age. Serum cystatin C (S-Cys C)-based prediction equations have been proposed as an improved potential alternative as S-Cys C levels are not influenced by many of the factors that affect creatinine concentration other than GFR. This may be of great benefit to patients with low muscle mass such as those infected with human immunodeficiency virus who are at increased risk for the development of renal impairment. The aim of this study was to develop and evaluate a S-Cys C-based prediction equation for different stages of renal disease in black South Africans.

METHODS

One hundred patients with varying degrees of renal function were enrolled in the study. The plasma clearance of (51)Cr-EDTA, a gold standard method, was used to measure GFR (mGFR). In addition, serum was analysed for S-Cr and S-Cys C on each participant. This dataset was split into a development dataset (n = 50) and a test dataset (n = 50). The development dataset was used to formulate a S-Cys C- and S-Cr-based prediction equation using multiple linear regression analysis. These equations together with the four-variable MDRD and CKD-EPI equation were then tested on the test dataset.

RESULTS

In the test dataset, accuracy within 15% of measured GFR was 68% for the S-Cys C equation and 48% for the S-Cr equation. Root mean square error for S-Cr eGFR was 10.7 mL/min/1.73 m(2) for those patients with mGFR < 60 mL/min/1.73 m(2) and 25.5 mL/min/1.73 m(2) for those patients with mGFR > 60 mL/min/1.73 m(2). Root mean square error for S-Cys C eGFR was 10.2 mL/min/1.73 m(2) for those patients with mGFR < 60 mL/min/1.73 m(2) and 11.9 mL/min/1.73 m(2) for those patients with mGFR > 60 mL/min/1.73 m(2).

CONCLUSIONS

In this study, S-Cys C-based prediction equations appear to be more precise than those of S-Cr for those patients with mGFR > 60 mL/min/1.73 m(2) and may therefore be of benefit in the earlier detection of renal impairment.

Comparative proteomic analysis of rat aorta in a subtotal nephrectomy model

Although accelerated atherosclerosis and arteriosclerosis are the main causes of cardiovascular morbidity and mortality in chronic kidney disease (CKD) patients, the molecular pathogenesis remains largely obscure. Our study of the aortic function in a typical CKD model of subtotal nephrectomy (SNX) rats demonstrated phenotypes that resemble CKD patients with aortic stiffness. The 2-DE analysis of rat aortas followed by MS identified 29 up-regulated and 53 down-regulated proteins in SNX rats. Further Western blot and immunohistochemistry analyses validated the decreased HSP27 and increased milk fat globule epidermal growth factor-8 (MFG-E8) in SNX rats. Functional classification of differential protein profiles using KOGnitor revealed that the two major categories involved in aortic stiffness are posttranslational modification, protein turnover, chaperones (23%) and cytoskeleton (21%). Ingenuity Pathway Analysis highlighted cellular assembly and organization, and cardiovascular system development and function as the two most relevant pathways. Among the identified proteins, the clinical significance of the secreted protein MFG-E8 was confirmed in 50 CKD patients, showing that increased serum MFG-E8 level is positively related to aortic stiffness and renal function impairment. Drug interventions with an inhibitor of the angiotensin converting enzyme, enalapril, in SNX rats improved aortic stiffness and decreased MFG-E8 depositions. Together, our studies provide a repertoire of potential biomarkers related to the aortic stiffness in CKD.

A simulation-aided factorial analysis approach for characterizing interactive effects of system factors on composting processes

A simulation-aided 2-level factorial analysis approach is proposed to characterize the interactive effects of composting factors (i.e. temperature, moisture, oxygen content and initial biomass concentration) on composting processes. To screen the important effect factors when high-order interactions occur, normal probability plot is applied to the result analysis. The results show that the factors have various effects on the composting process in different stages. At the 24th hour, the factors do not show significant effects on the composting process. At the 72nd hour when the composting process reaches active stage, the factors have important effects on the composting process, and their interactive effects are also significant. At the 144th hour, temperature and oxygen content still have effects on the composting process, but not as significant as those at the active stage. These findings could be useful for guiding composting-process operation and management and developing associated control strategies in different composting stages.

Studies of SARS virus vaccines

1. Intranasal vaccination using inactivated SARS coronavirus (SARS-CoV) vaccine with adjuvant can induce strong systemic (serum immunoglobulin [Ig] G) and respiratory tract local (tracheal-lung wash fluid IgA) antibody responses with neutralising activity. 2. RBD-Fc (protein-based vaccine) is able to induce effective neutralising antibodies able to provide protection from SARS-CoV infection in animal models. 3. A single dose of RBD-rAAV vaccination can induce adequate neutralising antibody against SARS-CoV infection. 4. Additional doses of vaccine increased the production of neutralising antibody 5-fold compared with a single dose. 5. RBD-rAAV vaccination provoked a prolonged antibody response with continually increasing levels of neutralising activity. 6. Intranasal vaccination with RBD-rAAV induced local IgA and systemic IgG neutralising antibodies and specific T-cell responses, able to protect against SARS-CoV infection in animal models. 7. When compared with the RBD-rAAV prime/boost vaccination, RBD-rAAV prime/RBD-peptide boost induced similar levels of Th1 and neutralising antibody responses that protected vaccinated mice from subsequent SARS-CoV challenges,but stronger Th2 and CTL responses. 8. Overall, our findings suggest that the inactivated vaccine, RBD-Fc and RBD-rAAV, can be further developed into effective and safe vaccines against SARS and that intranasal vaccination may be the preferred route of administration.

Determinants of catheter loss following continuous ambulatory peritoneal dialysis peritonitis

BACKGROUND

Few patients are able to resume peritoneal dialysis (PD) therapy after an episode of peritonitis that requires catheter removal. PD catheter loss is therefore regarded as an important index of patient morbidity. The aim of the present study was to evaluate factors influencing catheter loss in patients suffering from continuous ambulatory PD (CAPD) peritonitis.

PATIENTS AND METHODS

We retrospectively reviewed 579 episodes of CAPD peritonitis from 1999 to 2006 in a tertiary-care referral hospital. Demographic, biochemical, and microbiological characteristics were recorded. Episodes resulting in PD catheter removal (n = 68; 12%) were compared by both univariate and multivariate analyses with those in which PD catheters were preserved.

RESULTS

The incidence of PD catheter loss increased as the number of organisms cultured increased (p = 0.001). Also, PD catheter removal was more likely to occur after peritonitis episodes with low serum albumin level (p = 0.004), those with long duration of PD effluent leukocyte count remaining above 100/microL (p < 0.001), those with concomitant tunnel infection (p < 0.001), those with concomitant exit-site infection (p = 0.005), and those with presence of catastrophic intra-abdominal visceral events (p < 0.001). Duration on PD preceding the peritonitis episode was of borderline significance (p = 0.080). On the contrary, initial PD effluent leukocyte count and serum level of C-reactive protein were not predictive of PD catheter loss. Micro-organisms of the Enterobacteriaceae family were the major pathogens responsible for PD catheter loss following polymicrobial peritonitis. Furthermore, we found that there was no association between polymicrobial peritonitis and the catastrophic intra-abdominal visceral event, although both resulted in a greater incidence of PD catheter loss. Among the single-organism group in our population, the microbiological determinants of PD catheter loss included fungi (p < 0.001), anaerobes (p = 0.018), and Pseudomonas sp (borderline significance: p = 0.095).

CONCLUSION

PD catheter loss as a consequence of peritonitis is related primarily to hypoalbuminemia, longer duration of PD effluent leukocyte count remaining above 100/muL, the etiologic source of the infection, and the organism causing the infection. Peritonitis associated with concomitant tunnel or exit-site infections and abdominal catastrophes were more likely to proceed to PD catheter loss. The microbiological determinants of PD catheter loss in the present study included polymicrobial infections caused by Enterobacteriaceae as well as monomicrobial pseudomonal, anaerobic, and fungal infections.

Determinants of Catheter Loss following Continuous Ambulatory Peritoneal Dialysis Peritonitis

Background

Few patients are able to resume peritoneal dialysis (PD) therapy after an episode of peritonitis that requires catheter removal. PD catheter loss is therefore regarded as an important index of patient morbidity. The aim of the present study was to evaluate factors influencing catheter loss in patients suffering from continuous ambulatory PD (CAPD) peritonitis.

Patients and Methods

We retrospectively reviewed 579 episodes of CAPD peritonitis from 1999 to 2006 in a tertiary-care referral hospital. Demographic, biochemical, and microbiological characteristics were recorded. Episodes resulting in PD catheter removal ( n = 68; 12%) were compared by both univariate and multivariate analyses with those in which PD catheters were preserved.

Results

The incidence of PD catheter loss increased as the number of organisms cultured increased ( p = 0.001). Also, PD catheter removal was more likely to occur after peritonitis episodes with low serum albumin level ( p = 0.004), those with long duration of PD effluent leukocyte count remaining above 100/μL ( p < 0.001), those with concomitant tunnel infection ( p < 0.001), those with concomitant exit-site infection ( p = 0.005), and those with presence of catastrophic intra-abdominal visceral events ( p < 0.001). Duration on PD preceding the peritonitis episode was of borderline significance ( p = 0.080). On the contrary, initial PD effluent leukocyte count and serum level of C-reactive protein were not predictive of PD catheter loss. Micro-organisms of the Enterobacteriaceae family were the major pathogens responsible for PD catheter loss following polymicrobial peritonitis. Furthermore, we found that there was no association between polymicrobial peritonitis and the catastrophic intra-abdominal visceral event, although both resulted in a greater incidence of PD catheter loss. Among the single-organism group in our population, the microbiological determinants of PD catheter loss included fungi ( p < 0.001), anaerobes ( p = 0.018), and Pseudomonas sp (borderline significance: p = 0.095).

Conclusion

PD catheter loss as a consequence of peritonitis is related primarily to hypoalbuminemia, longer duration of PD effluent leukocyte count remaining above 100/μL, the etiologic source of the infection, and the organism causing the infection. Peritonitis associated with concomitant tunnel or exit-site infections and abdominal catastrophes were more likely to proceed to PD catheter loss. The microbiological determinants of PD catheter loss in the present study included polymicrobial infections caused by Enterobacteriaceae as well as monomicrobial pseudomonal, anaerobic, and fungal infections.

Differential effects of age on carotid augmentation index and aortic pulse wave velocity in end-stage renal disease patients

BACKGROUND

In healthy, normotensive individuals, age-related changes in carotid augmentation index (AI) are more prominent in younger individuals (< 50 years), whereas changes in aortic pulse wave velocity (PWV) are more marked in older individuals (> 50 years). We investigated whether the differential effects of age on AI and PWV also existed in end-stage renal disease (ESRD) patients.

METHODS

Two hundred and fifty-seven patients (50% male; mean age, 53.9 +/- 15.0 years) with ESRD and 260 normal controls (52% male; mean age, 51.4 +/- 17.8 years) received a comprehensive evaluation of cardiovascular structure and function.

RESULTS

The percent differences in PWV between the younger and older subjects were similar in both ESRD patients (+46.2%) and normal controls (+52.5%). The percent differences in PWV between normal controls and ESRD patients were also similar in both younger (+28.2%) and older (+22.9%) subjects. In contrast, the differences in AI between the younger and older subjects were small in ESRD patients (7.3%) but large in normal controls (19.7%). Furthermore, there was a large difference in AI between normal controls and ESRD patients in the younger (+13.3%) subjects, but no difference in the older subjects (+0.8%) (interaction between study groups and age: p < 0.001).

CONCLUSION

Markedly differential effects of age on AI and PWV were observed in ESRD patients. PWV increased with age similarly in both ESRD patients and normal controls, whereas AI increased markedly in the younger but only slightly in the older ESRD patients.

Modeling of substrate degradation and oxygen consumption in waste composting processes

A multi-component modeling system was developed to simulate substrate degradation and oxygen consumption in waste composting processes. Levels of soluble substrate (Ss), insoluble substrate (Si), active biomass (X), inert material, moisture, temperature, and oxygen concentration were considered as state variables. The relationships among these variables were also incorporated within the modeling framework. Three conversion reactions, including growth of aerobic biomass, decay of aerobic biomass, and solubilisation of insoluble substrate, were considered in the simulation system. The modeling inputs included temperature, moisture, oxygen concentration, and initial conditions of the state variables, while the outputs included oxygen uptake accumulation (OUA), oxygen uptake rate (OUR), Ss, Si, and X for representing the substrate degradation and oxygen consumption status. The effectiveness of the developed model was demonstrated through its application to a case study in a 30L vessel over 200h. Through verification-based composting experiments, it was shown that the modeling solutions were consistent with the experimental results with an acceptable accuracy level. Sensitivity analyses of the model showed that an increased maximum microbial growth rate would result in raised OUA, OUR, Ss, and X levels; a decreased biomass decay rate constant would help enhance the composting process. Moreover, variations in the maximum growth rate would affect the composting process more significantly than those of the biomass decay rate constant.

Separation method based on affinity reaction between magnetic and nonmagnetic particles for the analysis of particles and biomolecules

A separation method is reported for particle and biochemical analysis based on affinity interactions between particle surfaces under magnetic field. In this method, magnetic particles with immunoglobulin G (IgG) or streptavidin on the surface are flowed through a separation channel to form a deposition matrix for selectively capturing nonmagnetic analytes with protein A or biotin on the surface due to specific antigen (Ag)--antibody (Ab) interactions. This separation method was demonstrated using model reactions of IgG--protein A and streptavidin-biotin on particle surface. The features of this new separation method are (1) the deposited Ag-Ab complex can be examined and further analyzed under the microscope, (2) a kinetic study of complex binding is possible, and (3) the predeposited matrix can be formed selectively and changed easily. The detection limits were about 10(-11) g. The running time was less than 10 min. The selectivities of studied particles were 94% higher than those of label-controlled particles. This method extends the applications of analytical magnetapheresis to nonmagnetic particles. Preliminary study shows that this separation method has a great potential to provide a simple, fast, and selective analysis for particles, blood cells, and immunoassay related applications.

Electron beam computed tomography evidence of aortic calcification as an independent determinant of coronary artery calcification

BACKGROUND

Imaging of the aorta has received less attention than imaging of the coronary beds, despite the possible link between aortic and coronary artery disease (CAD). Electron beam computed tomography (EBCT) with 100 ms scanning speed can eliminate pulsation-related motion artifacts. The goals of this study were to evaluate EBCT-detected subclinical atherosclerosis over the whole aorta as in routine abdominal and thoracic CT scans and analyze whether or not the measurements of aortic calcification (AC) can independently predict the presence of coronary artery calcification (CAC), which is a surrogate marker of CAD.

METHODS

A consecutive series of 196 adults (male:female, 127:69; mean age, 65.9 +/- 10.5 years) were enrolled for EBCT examinations of the coronary arteries and whole aorta. CAC and AC were calculated by the Agatston method. Major cardiovascular risk factors were also recorded.

RESULTS

The greatest amount of AC was seen at the abdominal aorta, followed by the descending aortic arch, thoracic aorta, and ascending aorta. Total AC was significantly correlated with CAC (r = 0.51, p < 0.001). After adjustment for major cardiovascular risk factors of age, gender, diabetes, hypertension, hypercholesterolemia, and family history, the three independent significant determinants of CAC were abdominal AC, thoracic descending AC, and male gender (model r2 = 0.495, p < 0.001). For receiver operating characteristic analysis in predicting the presence of CAC, the threshold of descending AC was 11, with 68.3% sensitivity and 75.0% specificity. The optimal threshold of abdominal AC was 123, with 74.1% sensitivity and 67.9% specificity.

CONCLUSION

AC values in different portions of the aorta are independent predictors for the presence of CAC.

New method of blood typing using analytical magnetapheresis

We report a new method of blood typing based on the agglutination of red blood cell (RBC) with serum-treated magnetic particles in analytical magnetapheresis. Blood typing of ABO was demonstrated. The agglutination patterns of RBCs are different for different blood types and can be used to determine the ABO blood typing in analytical magnetapheresis. Six samples can be tested in each run. The running time was less than 10 min. Magnetic particles were prepared in the laboratory. The amount of RBCs needed for the agglutination test was about 1.0 microl of adult blood. The blood typing of ABO was used to illustrate the capable applications of analytical magnetapheresis to nonmagnetic samples like cells without magnetic labels. Analytical magnetapheresis has a great potential for cell related analysis.

Rapid recurrence of hyperparathyroidism from both nodularly hyperplastic autograft at forearm and residual tissues at neck after parathyroidectomy in a hemodialysis patient with calciphylaxis

A 42-year-old woman underwent hemodialysis secondary to diabetic nephropathy. Total parathyroidectomy with forearm autograft was performed due to secondary hyperparathyroidism (HPT) complicated with calciphylaxis. Rapidly progressive enlargement of autograft with unusual "gourd-shape" developed, and then it was removed. Pathologic examination of the autograft disclosed multinodular hyperplasia. Residual parathyroid gland in the retrothyroid region was found later. Rapidly recurrent HPT originating from both the residual parathyroid tissues and the enlarged autograft within such short time after parathyroidectomy is rare in the literature. The multinodular hyperplasia pattern of the parathyroid gland may be a major factor for such rapid recurrence. In addition to good control of calcium and phosphate, regular follow-up of parathyroid hormone level and imaging studies of not only autografted gland at the forearm but also possibly residual parathyroid tissues at the neck are important for monitoring recurrence in maintenance hemodialysis patients after parathyroidectomy with forearm autograft, especially in those with pathologic type of nodular hyperplasia and calciphylaxis.