Antibody repertoire sequencing (Rep-seq) has been widely used to reveal repertoire dynamics and to interrogate antibodies of interest at single nucleotide-level resolution. However, polymerase chain ...reaction (PCR) amplification introduces extensive artifacts including chimeras and nucleotide errors, leading to false discovery of antibodies and incorrect assessment of somatic hypermutations (SHMs) which subsequently mislead downstream investigations. Here, a novel approach named DUMPArts, which improves the accuracy of antibody repertoires by labeling each sample with dual barcodes and each molecule with dual unique molecular identifiers (UMIs)
minimal PCR amplification to remove artifacts, is developed. Tested by ultra-deep Rep-seq data, DUMPArts removed inter-sample chimeras, which cause artifactual shared clones and constitute approximately 15% of reads in the library, as well as intra-sample chimeras with erroneous SHMs and constituting approximately 20% of the reads, and corrected base errors and amplification biases by consensus building. The removal of these artifacts will provide an accurate assessment of antibody repertoires and benefit related studies, especially mAb discovery and antibody-guided vaccine design.
Heat shock protein 72 (HSP72) has been shown to attenuate unilateral ureteral obstruction–induced kidney fibrosis. It remains unknown whether HSP72 has direct effects on fibroblast proliferation in ...the renal fibrotic evolution. Herein, we first confirmed that increased HSP72 expression occurred in fibrotic human kidneys. Using three different animal models of kidney fibrosis, pharmacological down-regulation or genetic deletion of endogenous HSP72 expression exacerbated STAT3 phosphorylation, fibroblast proliferation, and tubulointerstitial fibrosis. In contrast, treatment with geranylgeranyl acetone, a specific inducer of HSP72, reduced phosphorylated STAT3 and protected animals from kidney fibrosis. In cultured renal interstitial fibroblasts, overexpression of HSP72 blocked transforming growth factor (TGF)-β1–induced cell activation and proliferation, as evidenced by inhibiting expression of α-smooth muscle actin, fibronectin, and collagen I/III, as well as by reducing cell numbers and DNA synthesis. Mechanical studies showed that overexpressed HSP72 attenuated TGF-β–induced phosphorylation and nuclear translocation of STAT3 and its downstream protein expression. However, siRNA knockdown of HSP72 increased TGF-β–induced STAT3 activity and fibroblast proliferation. Ectopic expression of a constitutively active STAT3 conferred resistance to HSP72 inhibition of fibroblast proliferation. Thus, HSP72 blocks fibroblast activation and proliferation in renal fibrosis via targeting the STAT3 pathway and may serve as a novel therapeutic agent for chronic kidney disease regardless of the etiology.
Introduction: Very early withdrawal from treatment in patients undergoing peritoneal dialysis (PD) is an increasingly important, but poorly understood, issue. Here, we identified the reasons and risk ...factors for very early withdrawal from PD.
Methods: Incident PD patients from The First Affiliated Hospital of Sun Yat-sen University above 18 years who started treatment between January 1 2006 and December 31 2011 were included. Cessation of PD therapy within the first 90 days after beginning dialysis was classified as very early withdrawal.
Results: Totally 1444 patients were enrolled. Of these, 71 (4.9%) withdrew from PD therapy during the first 90 days. Primary reasons for very early withdrawal included death (34 patients, 47.9%), transplantation (21 patients, 29.6%) and transfer to hemodialysis (14 patients, 19.7%). The leading reasons for death were cardiovascular and infectious disease, accounting for 41.2% (14 patients) and 23.5% (8 patients) of total deaths, respectively. Dialysate leakage (six patients, 42.9%) and catheter dysfunction (five patients, 35.7%) were the main reasons for transfer to hemodialysis. In multivariate analysis, predictors for very early PD withdrawal were older age (per decade increasing; hazard ratio HR, 1.22; 95% confidence interval CI, 1.03-1.45; p = .019), higher systolic blood pressure (per 10 mmHg increasing; HR, 1.35; 95% CI, 1.20-1.50; p < .001), lower hemoglobin (per 10 g/l increasing; HR, 0.67; 95% CI, 0.57-0.78; p < .001), lower high-density lipoprotein cholesterol (HR, 0.24; 95% CI, 0.10-0.54; p = .001) and lower residual urine volume (per 100 ml/d increasing; HR, 0.90; 95% CI, 0.84-0.95; p = .001).
Conclusions: Death was the primary reason for very early withdrawal from PD. Risk factors for very early withdrawal from PD were older in age, had higher systolic blood pressure, lower hemoglobin, lower high-density lipoprotein cholesterol and lower residual urine volume.
Severe temperature gradients and inhomogeneous strain distribution exist in the large cross-section of GCr15 bearing steel during the hot bar rolling process, resulting in a complex microstructure ...evolution in the bar. To promote the performance of the bar, a thermal-mechanical coupled finite element (FE) model was developed to capture the variations in temperature and deformation strain. A subroutine, considering the dynamic recrystallization (DRX), meta-dynamic recrystallization (MDRX), static recrystallization (SRX), and grain growth (GG) of austenite grains of GCr15 steel, was developed and coupled to the FE model to predict the microstructure’s evolution during rough rolling. The simulation implies that the inner part of the bloom is deformed at high temperatures due to the heat generated by plastic deformation and slow heat conduction, while the surface temperature decreases along with the passes. The heavy reduction design with 11 passes was found to introduce higher strains at the center regions than those of the same rough rolling reduction divided into 13 passes. The higher strains at the center regions refined the grain size and promoted microstructure homogeneity. The observation of the microstructures after hot bar rolling confirmed the refinement of the heavy reduction design for rough rolling. Furthermore, the heavy rough rolling reduction was found to be beneficial for alleviating the macrosegregation of the casting bloom.
The prevalence of chronic kidney disease (CKD) at high altitude is not known. We conducted a population-based survey in Tibet to identify the prevalence and associated risk factors of CKD in subjects ...living at altitudes of > 3500 m.
One thousand two hundred and eighty-nine Tibetans (≥ 18 years) from four districts of Lhasa city (altitude 3658 m) and eight villages of Dangxiong County (altitude 4200 m) were interviewed and tested for haematuria, albuminuria and estimated glomerular filtration rate (eGFR).
The adjusted prevalence of hypertension, albuminuria, haematuria and reduced eGFR were 38.8% (95% CI: 36.2-41.5%), 16.2% (95% CI: 14.1-18.2%), 3.9% (95% CI: 2.8-4.9%) and 2.1% (95% CI: 1.3-2.9%), respectively. Both the presence of hypertension and the presence of albuminuria were strongly and independently associated with hyperuricaemia and elevated haematocrit.
This is the first population-based epidemiological study of CKD in the Tibetan population. We found a higher prevalence of CKD and associated high prevalence of albuminuria, hypertension, hyperuricaemia and high haematocrit in the Tibetan population. The present study indicates the urgent need to develop comprehensive strategies targeted at reducing the CKD burden in this area and may lead to a better understanding of CKD in high-altitude populations.
Diabetic kidney disease (DKD) is a serious and common complication of diabetes. Extracellular vesicles (EVs) have emerged as crucial vectors in cell-to-cell communication during the development of ...DKD. EVs may mediate intercellular communication between podocytes and proximal tubules. In this study, EVs were isolated from podocyte culture supernatants under high glucose (HG), normal glucose (NG), and iso-osmolality conditions, and then co-cultured with proximal tubular epithelial cells (PTECs). MicroRNAs (miRNA) sequencing was conducted to identify differentially expressed miRNAs of podocyte EVs and bioinformatics analysis was performed to explore their potential functions. The results showed that EVs secreted from HG-treated podocytes induced apoptosis of PTECs. Moreover, five differentially expressed miRNAs in response to HG condition were identified. Functional enrichment analysis revealed that these five miRNAs are likely involved in biological processes and pathways related to the pathogenesis of DKD. Overall, these findings demonstrate the pro-apoptotic effects of EVs from HG-treated podocytes on PTECs and provide new insights into the pathologic mechanisms underlying DKD.
Urgent-start peritoneal dialysis (PD) can help patients with end-stage renal diseases (ESRD) that are referred late to dialysis. However, catheter patency and related complications of urgent-start PD ...have not been thoroughly clarified. We investigated the clinical outcomes of urgent-start PD in a Chinese cohort.
We enrolled ESRD patients who received urgent-start PD (starting PD within 14 days after catheter insertion) in our center from January 1, 2006 to December 31, 2014, and followed them up for 10 years. The primary outcome was catheter failure. Secondary outcomes included short-term and long-term complications related to urgent-start PD.
Totally 2059 patients (58.9% male, mean age 47.6 ± 15.9 years) were enrolled. Few perioperative complications were observed, including significant hemorrhage (n = 3, 0.1%) and bowel perforation (n = 0). Early peritonitis occurred in 24 (1.2%) patients (0.28 episodes per patient-year). Within the first month after catheter insertion, functional catheter malfunction occurred in 85 (4.1%) patients, and abdominal wall complications (including hernia, hydrothorax, hydrocele, and leakage) in 36 (1.7%) patients. During a median 36.5 (17.7-61.4) months of follow-up, 75 (3.6%) patients experienced catheter failure, and 291 (14.1%) had death-censoring technique failure. At the end of 1-month, 1 -year, 3-year, and 5-year, catheter patency rate was 97.6, 96.4, 96.2, 96.2%; and technique survival rate was 99.5, 97.0, 90.3, 82.7%, respectively. After adjusting for confounders, every 5-year increase in age was associated with 19% decrease of risk for catheter failure (hazard ratio HR: 0.81, 95% confidence interval CI: 0.73-0.89). Male sex (HR: 1.43, 95% CI: 1.00-2.04), diabetic nephropathy (HR: 1.56, 95% CI: 1.08-2.25) and low hemoglobin levels (HR: 0.89, 95% CI: 0.81-0.98) were independent risk factors for abdominal wall complications.
Urgent-start PD is a safe and efficacious option for unplanned ESRD patients. A well-trained PD team, a standardized catheter insertion procedure by experienced nephrologists, and a carefully designed initial PD prescription as well as comprehensive follow-up care, might be essential for the successful urgent-start PD program.
Previously, this study demonstrates the critical role of myeloid specific TLR4 in macrophage‐mediated progressive renal injury in anti‐glomerular basement membrane (anti‐GBM) crescentic ...glomerulonephritis (cGN); however, the underlying mechanism remains largely unknown. In this study, single‐cell RNA sequencing (scRNA‐seq), pseudotime trajectories reconstruction, and motif enrichment analysis are used, and macrophage diversity in anti‐GBM cGN under tight regulation of myeloid‐TLR4 is uncovered. Most significantly, a myeloid‐TLR4 deletion‐induced novel reparative macrophage phenotype (Nr4a1+Ear2+) with significant upregulated anti‐inflammatory and tissue repair‐related signaling is discovered, thereby suppressing the M1 proinflammatory responses in anti‐GBM cGN. This is further demonstrated in vitro that deletion of TLR4 from bone marrow‐derived macrophages (BMDMs) induces the Nr4a1/Ear2‐expressing anti‐inflammatory macrophages while blocking LPS‐stimulated M1 proinflammatory responses. Mechanistically, activation of the Nr4a1/Ear2‐axis is recognized as a key mechanism through which deletion of myeloid‐TLR4 promotes the anti‐inflammatory macrophage differentiation in vivo and in vitro. This is confirmed by specifically silencing macrophage Nr4a1 or Ear2 to reverse the anti‐inflammatory effects on TLR4 deficient BMDMs upon LPS stimulation. In conclusion, the findings decode a previously unidentified role for a myeloid‐TLR4 dependent Nr4a1/Ear2 negative feedback mechanism in macrophage‐mediated progressive renal injury, implying that activation of Nr4a1‐Ear2 axis can be a novel and effective immunotherapy for anti‐GBM cGN.
In this study, the authors discover that deletion of myeloid TLR4 inhibits immunologically mediated crescentic glomerulonephritis (cGN) by inducing a novel Nr4a1/Ear2‐expressing anti‐inflammatory macrophages while suppressing M1 proinflammatory responses. Findings from this study decode a previously unidentified role for a myeloid‐TLR4 dependent Nr4a1/Ear2 negative feedback mechanism in macrophage‐mediated progressive renal injury.
Technique failure is more likely to occur during the first 12 months after peritoneal dialysis (PD) initiation, which is a great challenge encountered in PD patients. The aim of this study was to ...investigate the incidence and risk factors associated with technique failure within the first year of PD patients in Southern China.
Incident PD patients who were followed up for at least one year at The First Affiliated Hospital of Sun Yat-sen University from January 1, 2006 to December 31, 2015 were included. Technique failure was defined as transferring to hemodialysis (HD) for more than 30 days or death within the first year after start of PD. A competitive risk regression analysis was used to explore the incidence and risk factors of the technique failure.
Overall, 2,290 incident PD patients were included in this study, with a mean age of 48.2 ± 15.7 years, 40.9% female and 25.2% with diabetes. A total of 173 patients (7.5%) had technique failure during the first year of PD. Among them, the patient death account for 62.4% (n = 108) and transferring to HD account for 37.6% (n = 65). The main reasons for death were cardiovascular diseases (n = 32, 29.6%), infection (n = 15, 13.8%) and for conversion to HD were mechanical cause (n = 28, 43.1%), infection cause (n = 22, 33.8%). The risk factors for the technique failure included advanced age (HR 2.78, 95%CI 1.82-4.30), low body mass index (BMI < 18.5 kg/m
: HR 1.77, 95%CI 1.17-2.67), history of congestive heart failure (HR 2.81, 95%CI 1.58-4.98), or time on HD before PD ≤ 3 months (HR 1.49, 95%CI 1.05-2.10), peritonitis (HR 2.02, 95%CI 1.36-3.01);while higher serum albumin (HR 0.93, 95%CI 0.89-0.96) and using employee medical insurance to pay expenses (HR 0.47, 95%CI 0.32-0.69) were associated with reduced risk.
Advanced age, poor nutritional status, history of HD or congestive heart failure, and peritonitis are related factors that increase the risk of technique failure in the first year of PD, while patients' type of medical insurance may also have an influence on early technique failure.
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