Expression of regional brain amyloid-ß deposition with [18F]Flutemetamol in Centiloid scale -a multi-site study.

PURPOSE: The Centiloid project helps calibrate the quantitative amyloid-ß (Aß) load into a unified Centiloid (CL) scale that allows data comparison across multi-site. How the smaller regional amyloid converted into CL has not been attempted. We first aimed to express regional Aß deposition in CL using [18F]Flutemetamol and evaluate regional Aß deposition in CL with that in standardized uptake value ratio (SUVr). Second, we aimed to determine the presence or absence of focal Aß deposition by measuring regional CL in equivocal cases showing negative global CL. METHODS: Following the Centiloid project pipeline, Level-1 replication, Level-2 calibration, and quality control were completed to generate corresponding Centiloid conversion equations to convert SUVr into Centiloid at regional levels. In equivocal cases, the regional CL was compared with visual inspection to evaluate regional Aß positivity. RESULTS: 14 out of 16 regional conversions from [18F]Flutemetamol SUVr to Centiloid successfully passed the quality control, showing good reliability and relative variance, especially precuneus/posterior cingulate and prefrontal regions with good stability for Centiloid scaling. The absence of focal Aß deposition could be detected by measuring regional CL, showing a high agreement rate with visual inspection. The regional Aß positivity in the bilateral anterior cingulate cortex was most prevalent in equivocal cases. CONCLUSION: The expression of regional brain Aß deposition in CL with [18F]Flutemetamol has been attempted in this study. Equivocal cases had focal Aß deposition that can be detected by measuring regional CL.

Concurrent JCPyV-DNAemia Is Correlated With Poor Graft Outcome in Kidney Transplant Recipients with Polyomavirus-associated Nephropathy.

BACKGROUND: Co-infection of JC polyomavirus (JCPyV) and BK polyomavirus (BKPyV) is uncommon in kidney transplant recipients, and the prognosis is unclear. This study aimed to investigate the effect of concurrent JCPyV-DNAemia on graft outcomes in BKPyV-infected kidney transplant recipients with polyomavirus-associated nephropathy (PyVAN). METHODS: A total of 140 kidney transplant recipients with BKPyV replication and PyVAN, 122 without concurrent JCPyV-DNAemia and 18 with JCPyV-DNAemia were included in the analysis. Least absolute shrinkage and selection operator regression analysis and multivariate Cox regression analysis were used to identify prognostic factors for graft survival. A nomogram for predicting graft survival was created and evaluated. RESULTS: The median tubulitis score in the JCPyV-DNAemia-positive group was higher than in JCPyV-DNAemia-negative group (P = 0.048). At last follow-up, the graft loss rate in the JCPyV-DNAemia-positive group was higher than in the JCPyV-DNAemia-negative group (50% versus 25.4%; P = 0.031). Kaplan-Meier analysis showed that the graft survival rate in the JCPyV-DNAemia-positive group was lower than in the JCPyV-DNAemia-negative group (P = 0.003). Least absolute shrinkage and selection operator regression and multivariate Cox regression analysis demonstrated that concurrent JCPyV-DNAemia was an independent risk factor for graft survival (hazard ratio = 4.808; 95% confidence interval: 2.096-11.03; P < 0.001). The nomogram displayed favorable discrimination (C-index = 0.839), concordance, and clinical applicability in predicting graft survival. CONCLUSIONS: Concurrent JCPyV-DNAemia is associated with a worse graft outcome in BKPyV-infected kidney transplant recipients with PyVAN.

Ultrasound-guided percutaneous high-frequency irreversible electroporation in porcine livers using four electrode needles: A feasibility and safety study.

BACKGROUND: Malignant liver tumors seriously endanger human health. Among different therapeutic approaches, high-frequency irreversible electroporation (H-FIRE) is a recently emerging tumor ablation technique. The objective of this study was to evaluate the feasibility and safety of ultrasound-guided percutaneous H-FIRE using four electrode needles in porcine livers. METHODS: Twelve experimental pigs underwent percutaneous H-FIRE ablation using a compound steep-pulse therapeutic device. Liver tissues adjacent to the gallbladder, blood vessels, and bile ducts were selected as the ablation targets. Pigs were randomly divided into three groups: (1) immediately after ablation (N = 4), (2) 2 days after ablation (N = 4), and (3) 7 days after ablation (N = 4). Blood routine, liver and kidney function, and myocardial enzyme levels were measured before and after ablation. Ultrasound, contrast-enhanced ultrasound (CEUS), contrast-enhanced magnetic resonance imaging (MRI), and hematoxylin-eosin staining were performed to evaluate the ablation performance. RESULTS: Ultrasound-guided percutaneous H-FIRE ablations using four electrode needles were successfully performed in all 12 experimental pigs. The general conditions of the pigs, including postoperative activities and feeding behaviors, were normal, with no significant changes compared with the preoperative conditions. The imaging features of ultrasound, CEUS, and MRI demonstrated no significant changes in the gallbladder walls, bile ducts, or blood vessels close to the ablation areas. Laboratory tests showed that liver function indices and myocardial enzymes increased temporarily after H-FIRE ablation, but decreased to normal levels at 7 days after ablation. Histopathological examinations of porcine liver specimens showed that this technique could effectively ablate the target areas without damaging the surrounding or internal vascular systems and gallbladder. CONCLUSIONS: This study demonstrated the feasibility and safety of ultrasound-guided percutaneous H-FIRE ablation in porcine livers in vivo, and proposed a four-needle method to optimize its clinical application.

Development of a clinical nomogram for prediction of response to neoadjuvant chemotherapy in patients with advanced gastric cancer.

BACKGROUND: The efficacy of neoadjuvant chemotherapy (NAC) in advanced gastric cancer (GC) is still a controversial issue. AIM: To find factors associated with chemosensitivity to NAC treatment and to provide the optimal therapeutic strategies for GC patients receiving NAC. METHODS: The clinical information was collected from 230 GC patients who received NAC treatment at the Central South University Xiangya School of Medicine Affiliated Haikou Hospital from January 2016 to December 2020. Least absolute shrinkage and selection operator logistic regression analysis was used to find the possible predictors. A nomogram model was employed to predict the response to NAC. RESULTS: In total 230 patients were finally included in this study, including 154 males (67.0%) and 76 females (33.0%). The mean age was (59.37 ± 10.60) years, ranging from 24 years to 80 years. According to the tumor regression grade standard, there were 95 cases in the obvious response group (grade 0 or grade 1) and 135 cases in the poor response group (grade 2 or grade 3). The obvious response rate was 41.3%. Least absolute shrinkage and selection operator analysis showed that four risk factors significantly related to the efficacy of NAC were tumor location (P < 0.001), histological differentiation (P = 0.001), clinical T stage (P = 0.008), and carbohydrate antigen 724 (P = 0.008). The C-index for the prediction nomogram was 0.806. The calibration curve revealed that the predicted value exhibited good agreement with the actual value. Decision curve analysis showed that the nomogram had a good value in clinical application. CONCLUSION: A nomogram combining tumor location, histological differentiation, clinical T stage, and carbohydrate antigen 724 showed satisfactory predictive power to the response of NAC and can be used by gastrointestinal surgeons to determine the optimal treatment strategies for advanced GC patients.

Hidden Valley Polarization, Piezoelectricity, and Dzyaloshinskii-Moriya Interactions of Janus Vanadium Dichalcogenides.

Due to the lack of inversion symmetry and the discovery of room-temperature ferromagnetism, two-dimensional semiconducting vanadium-based van der Waals transition-metal dichalcogenides (V-TMDs) are drawing attention for their possible application in spintronics and valleytronics. Here, we show the functional properties enriched by the broken inversion, out-of-plane mirror, and time-reversal symmetries of Janus H-VXY TMDs (X, Y = S, Se, Te). By first-principles calculations, we reveal the intrinsic xy easy-plane magnetism of the Janus vanadium-based TMD monolayers and systematically study their hidden valley polarization and giant magneto band structure. Their strong nearest-neighbor exchange strengths lead to near-room-temperature magnetic phase transitions. The Janus H-VXY system also exhibits piezoelectricity with nonzero e31 and e21. Interestingly, it is found that the right-handed Dzyaloshinskii-Moriya interaction has nonzero in-plane components in our Janus system, with fluctuating magnitudes determined by competence between relaxed bond-angle and atomic index of ligands.

Outcomes of Robotic Versus Laparoscopic Pancreatoduodenectomy Following Learning Curves of Surgeons: A Multicenter Study on 2255 Patients.

OBJECTIVE: This study aimed to compare robotic pancreatoduodenectomy (RPD) with laparoscopic pancreatoduodenectomy (LPD) in operative and oncologic outcomes. BACKGROUND: Previous studies comparing RPD with LPD have only been carried out in small, single-center studies with variable quality. METHODS: Consecutive patients from nine centers in China who underwent RPD or LPD between 2015 and 2022 were included. A 1:1 propensity score matching (PSM) was used to minimize bias. RESULTS: Of the 2,255 patients, 1158 underwent RPD and 1097 underwent LPD. Following PSM, 1006 patients were enrolled in each group. The RPD group had significantly shorter operative time (270.0 vs. 305.0 minutes, P<0.001), lower intraoperative blood transfusion rate (5.9% vs. 12.0%, P<0.001), lower conversion rate (3.8% vs. 6.7%, P=0.004), and higher vascular reconstruction rate (7.9% vs. 5.6%, P=0.040) than the LPD group. There were no significant differences in estimated blood loss, postoperative length of stay, perioperative complications, and 90-day mortality. Patients who underwent vascular reconstruction had similar outcomes between the two groups, although they had significantly lower estimated blood loss (300.0 vs. 360.0 mL; P=0.021) in the RPD group. Subgroup analysis on pancreatic ductal adenocarcinoma (PDAC) found no significant differences between the two groups in median recurrence-free survival (14.3 vs. 15.3 mo, P=0.573) and overall survival (24.1 vs. 23.7 mo, P=0.710). CONCLUSIONS: In experienced hands, both RPD and LPD are safe and feasible procedures with similar surgical outcomes. RPD had the perioperative advantage over LPD especially in vascular reconstruction. For PDAC patients, RPD resulted in similar oncological and survival outcomes as LPD.

Short-term outcomes of robotic versus open hepatectomy among overweight patients with hepatocellular carcinoma: a propensity score-matched study.

BACKGROUND: Robotic hepatectomy (RH) has gradually been accepted as it has overcome some of the limitations of open hepatectomy (OH). This study was to compare short-term outcomes in RH and OH for overweight (preoperative body mass index ≥ 25 kg/m²) patients with hepatocellular carcinoma (HCC). METHODS: Perioperative and postoperative data from these patients who underwent RH or OH between January 2010 and December 2020 were retrospectively analyzed. Propensity score matching (PSM) analysis was performed to determine the impact of RH versus OH on the prognosis of overweight HCC patients. RESULTS: All 304 overweight HCC patients were included, 172 who were underwent RH, and 132 who were underwent OH. After the 1:1 PSM, there were 104 patients in both RH and OH groups. After PSM, the RH group of patients had a shorter operative time, less estimated blood loss (EBL), a longer total clamping time, a shorter postoperative length of stay (LOS), less chance of surgical site infection and less rates of blood transfusion (all P < 0.05) compared to the OH patients. The differences between operative time, EBL and LOS were more significant in obese patients. RH was found to be an independent protective factor of EBL ≥ 400ml relative to OH in overweight patients for the first time. CONCLUSIONS: RH was safe and feasible in overweight HCC patients. Compared with OH, RH has advantages in terms of operative time, EBL, postoperative LOS, and surgical site infection. Carefully selected overweight patients should be considered for RH.

Early and late recurrence patterns of pancreatic ductal adenocarcinoma after pancreaticoduodenectomy: a multicenter study.

BACKGROUND: Survival after pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) remains poor because of high incidences of recurrence. The risk factors, patterns, and long-term prognosis in patients with early recurrence and late recurrence (ER and LR) for PDAC after PD were studied. METHODS: Data from patients who underwent PD for PDAC were analyzed. Recurrence was divided into ER (ER ≤1 years) and LR (LR >1 years) using the time to recurrence after surgery. Characteristics and patterns of initial recurrence, and postrecurrence survival (PRS) were compared between patients with ER and LR. RESULTS: Among the 634 patients, 281 (44.3%) and 249 (39.3%) patients developed ER and LR, respectively. In the multivariate analysis, preoperative CA19-9 levels, resection margin status, and tumor differentiation were significantly associated with both ER and LR, while lymph node metastasis and perineal invasion were associated with LR. Patients with ER, when compared with patients with LR, showed a significantly higher proportion of liver-only recurrence ( P <0.05), and worse median PRS (5.2 vs. 9.3 months, P <0.001). Lung-only recurrence had a significantly longer PRS when compared with liver-only recurrence ( P <0.001). Multivariate analysis demonstrated that ER and irregular postoperative recurrence surveillance were independently associated with a worse prognosis ( P <0.001). CONCLUSION: The risk factors for ER and LR after PD are different for PDAC patients. Patients who developed ER had worse PRS than those who developed LR. Patients with lung-only recurrence had a significantly better prognosis than those with other recurrent sites.

Single-Cell Transcriptome Identifies the Renal Cell Type Tropism of Human BK Polyomavirus.

BK polyomavirus (BKPyV) infection is the main factor affecting the prognosis of kidney transplant recipients, as no antiviral agent is yet available. A better understanding of the renal-cell-type tropism of BKPyV can serve to develop new treatment strategies. In this study, the single-cell transcriptomic analysis demonstrated that the ranking of BKPyV tropism for the kidney was proximal tubule cells (PT), collecting duct cells (CD), and glomerular endothelial cells (GEC) according to the signature of renal cell type and immune microenvironment. In normal kidneys, we found that BKPyV infection-related transcription factors P65 and CEBPB were PT-specific transcription factors, and PT showed higher glycolysis/gluconeogenesis activities than CD and GEC. Furthermore, in the BKPyV-infected kidneys, the percentage of late viral transcripts in PT was significantly higher than in CD and GEC. In addition, PT had the smallest cell-cell interactions with immune cells compared to CD and GEC in both normal and BKPyV-infected kidneys. Subsequently, we indirectly demonstrated the ranking of BKPyV tropism via the clinical observation of sequential biopsies. Together, our results provided in-depth insights into the renal cell-type tropism of BKPyV in vivo at single-cell resolution and proposed a novel antiviral target.

Derivation and validation of a preoperative prognostic model for resectable pancreatic ductal adenocarcinoma.

BACKGROUND: The prognosis of patients with pancreatic ductal adenocarcinoma (PDAC) remains poor even after radical pancreaticoduodenectomy (PD). The study aimed to develop and validate a novel preoperative prognostic model to accurately predict the long-term survival of patients with PDAC. METHODS: Patients with PDAC of pancreatic head from Chinese PLA General Hospital were included. The preoperative PDAC model with contour plots was developed using a non-linear model in the training cohort and then tested in the validation cohort. RESULTS: Of 421 patients who met the inclusion criteria, 280 were in the training cohort and 141 in the validation cohort. Contour plots for preoperative PDAC model were established to visually predict the survival probabilities of these patients, based on preoperative carbohydrate antigen 19-9, preoperative fibrinogen to albumin ratio and pain symptoms. This model stratified patients into low- and high-risk groups with distinctly different long-term survival in the training cohort [median overall survival (OS) 32.1 vs. 17.5 months; median recurrence-free survival (RFS) 19.3 vs. 10.0 months, both P < 0.001] and the validation cohort (median OS 28.3 vs. 19.0 months; median RFS 17.5 vs. 11.2 months, both P < 0.001). Time-dependent receiver operating characteristic and decision curve analyses revealed that the model provided higher diagnostic accuracy and superior net benefit compared to other staging systems. CONCLUSIONS: This study constructed and validated a novel preoperative prognostic model that can accurately and conveniently predict the long-term survival of patients with resectable PDAC of pancreatic head. Besides, the model can screen high-risk patients with poor prognosis, which may provide references for personal treatment strategies in the future.

Robotic pancreaticoduodenectomy for pancreatic ductal adenocarcinoma: Analysis of surgical outcomes and long-term prognosis in a high-volume center.

BACKGROUND: Robotic pancreaticoduodenectomy (RPD) has been reported to be safe and feasible for patients with pancreatic ductal adenocarcinoma (PDAC) of the pancreatic head. This study aimed to analyze the surgical outcomes and risk factors for poor long-term prognosis of these patients. METHODS: Data from patients who underwent RPD for PDAC of pancreatic head were retrospectively analyzed. Multivariate Cox regression analysis was used to seek the independent prognostic factors for overall survival (OS), and an online nomogram calculator was developed based on the independent prognostic factors. RESULTS: Of the 273 patients who met the inclusion criteria, the median operative time was 280.0 minutes, the estimated blood loss was 100.0 mL, the median OS was 23.6 months, and the median recurrence-free survival (RFS) was 14.4 months. Multivariate analysis showed that preoperative carbohydrate antigen 19-9 (CA19-9) [hazard ratio (HR) = 2.607, 95% confidence interval (CI): 1.560-4.354, P < 0.001], lymph node metastasis (HR = 1.429, 95% CI: 1.005-2.034, P = 0.047), tumor moderately (HR = 3.190, 95% CI: 1.813-5.614, P < 0.001) or poorly differentiated (HR = 5.114, 95% CI: 2.839-9.212, P < 0.001), and Clavien-Dindo grade ≥ III (HR = 1.657, 95% CI: 1.079-2.546, P = 0.021) were independent prognostic factors for OS. The concordance index (C-index) of the nomogram constructed based on the above four independent prognostic factors was 0.685 (95% CI: 0.640-0.729), which was significantly higher than that of the AJCC staging (8th edition): 0.541 (95% CI: 0.493-0.589) (P < 0.001). CONCLUSIONS: This large-scale study indicated that RPD was feasible for PDAC of pancreatic head. Preoperative CA19-9, lymph node metastasis, tumor poorly differentiated, and Clavien-Dindo grade ≥ III were independent prognostic factors for OS. The online nomogram calculator could predict the OS of these patients in a simple and convenient manner.

A novel online calculator to predict early recurrence and long-term survival of patients with resectable pancreatic ductal adenocarcinoma after pancreaticoduodenectomy: A multicenter study.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is prone to relapse even after radical pancreaticoduodenectomy (PD) (including robotic, laparoscopic and open approach). This study aimed to develop an online nomogram calculator to predict early recurrence (ER) (within one year after surgery) and long-term survival in patients with PDAC. METHODS: Patients with PDAC after radical PD were included. Univariate and multivariate logistic regression analysis was used to identify independent risk factors. An online nomogram calculator was developed based on independent risk factors in the training cohort and then tested in the internal and external validation cohorts. RESULTS: Of the 569 patients who met the inclusion criteria, 310, 155, and 104 patients were in the training, internal and external validation cohorts, respectively. Multivariate analysis revealed that preoperative carbohydrate antigen19-9 (CA19-9) [Odds Ratio (OR) 1.002; 95% confidence interval (CI) 1.001-1.003; P = 0.001], fibrinogen/albumin (FAR) (OR 1.132; 95% CI 1.012-1.266; P = 0.029), N stage (OR 2.291; 95% CI 1.283-4.092; P = 0.005), and tumor differentiation (OR 3.321; 95% CI 1.278-8.631; P = 0.014) were independent risk factors for ER. Nomogram based on the above four factors achieved good C-statistics of 0.772, 0.767 and 0.765 in predicting ER in the training, internal and external validation cohorts, respectively. Time-dependent ROC analysis (timeROC) and decision curve analysis (DCA) revealed that the nomogram provided superior diagnostic capacity and net benefit compared with other staging systems. CONCLUSION: This multi-center study developed and validated an online nomogram calculator that can predict ER and long-term survival in patients with PDAC with high degrees of stability and accuracy.

Short- and long-term outcomes after robotic and open liver resection for elderly patients with hepatocellular carcinoma: a propensity score-matched study.

BACKGROUND: Robotic liver resection (RLR) has increasingly been accepted as it has overcome some of the limitations of open liver resection (OLR), while the outcomes following RLR in elderly patients with hepatocellular carcinoma (HCC) are still uncertain. This study aimed to evaluate the short and long-term outcomes of RLR vs. OLR in elderly HCC patients. METHODS: Perioperative data of elderly patients (≥ 65 years) with HCC who underwent RLR or OLR between January 2010 and December 2020 were retrospectively analyzed. A 1:2 propensity score-matched (PSM) analysis was performed to minimize the differences between RLR and OLR groups. Univariable and multivariable Cox regression analyses were used to identify independent prognosis factors for overall survival (OS) and recurrence-free survival (RFS) of these patients. RESULTS: Of the 427 elderly HCC patients included in this study, 113 underwent RLR and 314 underwent OLR. After the 1:2 PSM, there were 100 and 178 patients in the RLR and the OLR groups, respectively. The RLR group had a less estimated blood loss (EBL), a shorter postoperative length of stay (LOS), and a lower complications rate (all P < 0.05), compared with the OLR group before and after PSM. Univariable and multivariable analyses showed that advanced age and surgical approaches were not independent risk factors for long-term prognosis. The two groups of elderly patients who were performed RLR or OLR had similar OS (median OS 52.8 vs. 57.6 months) and RFS (median RFS 20.4 vs. 24.6 months) rates after PSM. CONCLUSIONS: RLR was comparable to OLR in feasibility and safety. For elderly patients with HCC, RLR resulted in similar oncologic and survival outcomes as OLR.

Robotic versus open pancreaticoduodenectomy for distal cholangiocarcinoma: a multicenter propensity score-matched study.

BACKGROUND: Pancreatoduodenectomy is the only potentially curative treatment for distal cholangiocarcinoma (DCC). In this study, we sought to compare the perioperative and oncological outcomes of robotic pancreaticoduodenectomy (RPD) and open pancreaticoduodenectomy (OPD) based on a multicenter propensity score-matched study. METHODS: Consecutive patients with DCC who underwent RPD or OPD from five centers in China between January 2014 and June 2019 were included. A 1:1 propensity score matching (PSM) was performed. Univariable and multivariable Cox regression analyses were used to identify independent prognosis factors for overall survival (OS) and recurrence-free survival (RFS) of these patients. RESULTS: A total of 217 patients and 228 patients underwent RPD and OPD, respectively. After PSM, 180 patients in each group were enrolled. There were no significant differences in operative time, lymph node harvest, intraoperative transfusion, vascular resection, R0 resection, postoperative major morbidity, reoperation, 90-day mortality, and long-term survival between the two groups before and after PSM. Whereas, compared with the OPD group, the RPD group had significantly lower estimated blood loss (150.0 ml vs. 250.0 ml; P < 0.001), and a shorter postoperative length of stay (LOS) (12.0 days vs. 15.0 days; P < 0.001). Multivariable analysis showed carbohydrate antigen 19-9 (CA19-9), R0 resection, N stage, perineural invasion, and tumor differentiation significantly associated with OS and RFS of these patients. CONCLUSIONS: RPD was comparable to OPD in feasibility and safety. For patients with DCC, RPD resulted in similar oncologic and survival outcomes as OPD.

Trends of cancer mortality in Xi'an City, China: 2005-2020.

PURPOSE: Describe and predict the malignant tumor deaths in Xi'an so as to provide evidence for the government to formulate the prevention and treatment plans. METHODS: Overall malignant tumor death in Xi'an in the past 16 years was described. The multi-decrease life table was used to calculate cumulative mortality risk by cause and life expectancy reduction years by cause of malignant tumors in 2020. The join point regression models were used to analyze the change trend of standard mortality of malignant tumors in Xi'an from 2005 to 2020. The appropriate gray models were selected to predict the death of malignant tumors in Xi'an in the next decade. RESULTS: The mortality of total malignant tumors in Xi'an showed that men are higher than women and the elderly are higher than other groups. As for 2020, lung cancer had the highest risk of death for both men and women, while leukemia had the highest life expectancy reduction years by cause. From 2005 to 2020, standardized mortality of majority malignant tumors showed downward trends, which were particularly obvious in recent years. The prediction results of several major malignant tumors showed that in the next decade, the mortality of most malignant tumors had downward trends, but combined with the increase of population in the future, the number of malignant tumor deaths in Xi'an will continue to increase. CONCLUSIONS: Malignant tumors in Xi'an have decreasing mortality trends in recent years, and effective measures to prevent and treat tumors should be strengthened in the future.

Using Both Plasma and Urine Donor-Derived Cell-Free DNA to Identify Various Renal Allograft Injuries.

BACKGROUND: This study was designed to investigate the association between donor-derived cell-free DNA (dd-cfDNA) and renal allograft injuries. METHODS: This single-center study enrolled 113 adult kidney transplant recipients with kidney biopsies. Plasma and urine dd-cfDNA was detected by target region capture sequencing. RESULTS: Plasma dd-cfDNA fraction was increased in multiple types of injuries, but most significantly in antibody-mediated rejection. Plasma dd-cfDNA fraction in isolated antibody-mediated rejection (1.94%, IQR: 1.15%, 2.33%) was higher than in T cell-mediated rejection (0.55%, IQR: 0.50%, 0.73%, P = 0.002) and negative biopsies (0.58%, IQR: 0.42%, 0.78%, P < 0.001), but lower than in mixed rejection (2.49%, IQR: 1.16%, 4.90%, P = 0.342). Increased urine dd-cfDNA concentration was associated with several types of injury, but most significantly with BK polyomavirus-associated nephropathy. Urine dd-cfDNA concentration in BK polyomavirus-associated nephropathy (12.22 ng/mL, IQR: 6.53 ng/mL, 31.66 ng/mL) was respectively higher than that in T cell-mediated rejection (5.24 ng/mL, IQR: 3.22 ng/mL, 6.99 ng/mL, P = 0.001), borderline change (3.93 ng/mL, IQR: 2.45 ng/mL, 6.30 ng/mL, P < 0.001), and negative biopsies (3.09 ng/mL, IQR: 1.94 ng/mL, 5.05 ng/mL, P < 0.001). Plasma dd-cfDNA fraction was positively associated with glomerulitis (r = 0.365, P < 0.001) and peri-tubular capillaritis (r = 0.344, P < 0.001), while urine dd-cfDNA concentration correlated with tubulitis (r = 0.302, P = 0.002). CONCLUSIONS: Both plasma and urine dd-cfDNA are sensitive markers for renal allograft injuries. The interpretation of a specific disease by dd-cfDNA should be combined with other clinical indicators.

Endoplasmic Reticulum Stress Mediates Renal Tubular Vacuolation in BK Polyomavirus-Associated Nephropathy.

Objective: This study aimed to explore the molecular mechanism of cytoplasmic vacuolation caused by BK polyomavirus (BKPyV) and thus search for potential target for drug repurposing. Methods: Morphological features of BK polyomavirus-associated nephropathy (BKPyVAN) were studied under light and electron microscopes. Microarray datasets GSE75693, GSE47199, and GSE72925 were integrated by ComBat, and differentially expressed genes (DEGs) were analyzed using limma. Furthermore, the endoplasmic reticulum (ER)-related genes obtained from GenCLiP 2.0 were intersected with DEGs. GO and KEGG enrichment pathways were performed with intersection genes by R package clusterProfiler. The single-cell RNA sequencing (scRNA-seq) from a BKPyVAN recipient was analyzed with a dataset (GSE140989) downloaded from Gene Expression Omnibus (GEO) as control for gene set variation analysis (GSVA). Immunohistochemistry and electron microscopy of kidney sections from drug-induced ERS mouse models were performed to explore the association of ERS and renal tubular vacuolation. Protein-protein interaction (PPI) network of the intersection genes was constructed to identify hub target. AutoDock was used to screen Food and Drug Administration (FDA)-approved drugs that potentially targeted hub gene. Results: Light and electron microscopes exhibited obvious intranuclear inclusions, vacuoles, and virus particles in BKPyV-infected renal tubular cells. Transcriptome analysis revealed 629 DEGs between samples of BKPyVAN and stable transplanted kidneys, of which 16 were ER-associated genes. GO analysis with the intersection genes illustrated that ERS-related pathways were significantly involved, and KEGG analysis showed a prominent enrichment of MAPK, Toll-like receptor, and chemokine signaling pathways. GSVA analysis of the proximal tubule revealed similar pathways enrichment. An electron microscope image of the kidney from ERS mouse models showed an obvious renal tubular vacuolation with prominent activation of ERS markers verified by immunohistochemistry. Furthermore, DDIT3 was identified as the hub gene based on PPI analysis, and ZINCOOOOO1531009 (Risedronate) was indicated to be a potential drug for DDIT3. Conclusion: ERS was involved in renal tubular cytoplasmic vacuolation in BKPyVAN recipients. Risedronate was screened as a potential drug for BKPyVAN by targeting DDIT3.

Ischemia-Reperfusion Injury and Immunosuppressants Promote Polyomavirus Replication Through Common Molecular Mechanisms.

Background: BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN) causes renal allograft dysfunction and graft loss. However, the mechanism of BKPyV replication after kidney transplantation is unclear. Clinical studies have demonstrated that immunosuppressants and renal ischemia-reperfusion injury (IRI) are risk factors for BKPyV infection. Studying the pathogenic mechanism of BKPyV is limited by the inability of BKPyV to infect the animal. Mouse polyomavirus (MPyV) is a close homolog of BKPyV. We used a model of MPyV infection to investigate the core genes and underlying mechanism of IRI and immunosuppressants to promote polyomavirus replication. Materials and Methods: One-day-old male C57BL/6 mice were intraperitoneally injected with MPyV. At week 9 post-infection, all mice were randomly divided into IRI, immunosuppressant, and control groups and treated accordingly. IRI was established by clamping the left renal pedicle. Subsequently, kidney specimens were collected for detecting MPyV DNA, histopathological observation, and high-throughput RNA sequencing. Weighted gene correlation network analysis (WGCNA), protein-protein interaction network analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were used to screen for core genes and common signaling pathways involved in promoting MPyV replication by IRI and immunosuppressants. Results: After primary infection, MPyV established persistent infection in kidneys and subsequently was significantly increased by IRI or immunosuppressant treatment individually. In the IRI group, viral loads peaked on day 3 in the left kidney, which were significantly higher than those in the right kidney and the control group. In the immunosuppressant group, viral loads in the left kidney were significantly increased on day 3, which were significantly higher than those in the control group. Protein-protein interaction network analysis and WGCNA screened complement C3, epidermal growth factor receptor (EGFR), and FN1 as core genes. Pathway enrichment analysis based on the IRI- or immunosuppressant-related genes selected by WGCNA indicated that the NF-κB signaling pathway was the main pathway involved in promoting MPyV replication. The core genes were further confirmed using published datasets GSE47199 and GSE75693 in human polyomavirus-associated nephropathy. Conclusions: Our study demonstrated that IRI and immunosuppressants promote polyomavirus replication through common molecular mechanisms. In future studies, knockdown or specific inhibition of C3, EGFR, FN1, and NF-κB signaling pathway will further validate their critical roles in promoting polyomavirus replication.

Step-by-step and orderly lowering of the height of inferior vena cava tumor thrombus is the key to robot-assisted thrombectomy for Mayo III/IV tumor thrombus.

BACKGROUND: The surgical management of Mayo III/IV tumor thrombi is difficult and risky, and robotic surgery is even more difficult. The purpose of this study was to introduce the step-by-step and orderly lowering of the height of inferior vena cava tumor thrombus, which was the core technique of robot operation for Mayo III/IV tumor thrombus. METHOD: A total of 18 patients were included in this study. The average tumor thrombus height was 2.4 cm above the level of the second porta hepatis (SPH), and 9 patients were prepared for cardiopulmonary bypass (CPB) before surgery. During the operation, the height of the tumor thrombus was lowered orderly for 2-3 times, and the blood flow blocking method was changed sequentially. The CPB was required when tumor thrombus in the atrium; After the height of the thrombus was lowered to the atrium entrance, CPB was stopped and the blood flow was blocked in the upper- and retro-hepatic inferior vena cava (IVC); After the tumor thrombus continued to descend to the lower part of the SPH, liver blood flow could be restored, and then, the blood flow was simply blocked in the retro-hepatic IVC to complete the removal of the thrombus and the repair or resection of the IVC. Finally, the diseased kidney and renal vein were removed. RESULTS: All operations were successfully completed, and 2 cases were transferred to laparotomy. Seven cases received CPB, while the other 11 did not. 15 patients underwent two times of the lowering of the tumor thrombus, 2 patients underwent one time and 1 patient underwent three times. The mean liver/IVC dissociation and vascular suspension time was 22.0 min. All patients had less than Clavien-Dindo grade III complications, no serious complications occurred during operation, and no patient died within 90 days. CONCLUSIONS: The step-by-step and orderly decline of tumor thrombus height is the key to the success of robot Mayo III / IV tumor thrombus surgery. This method can shorten FPH and CPB time and improve the success rate of surgery.