BackgroundCalcium oxalate (CaOx) nephrolithiasis is closely associated with metabolic dysregulation, while current risk assessment based on 24-h urine analysis is time-consuming and inconvenient. This study aimed to develop a noninvasive predictive model for CaOx stones using morning urine organic acid and inorganic ion profiles combined with machine learning, and to identify metabolomic biomarkers related to CaOx stone formation.MethodsA total of 232 CaOx stone formers and 238 healthy controls were enrolled. Organic acids and inorganic ions in morning urine were quantified by gas chromatography–mass spectrometry and ion chromatography, respectively. Participants were randomly divided into training and testing sets (8:2). Diagnostic models were constructed using random forest, support vector machine, logistic regression, and extreme gradient boosting, with 10-fold cross-validation for optimization. Model performance was evaluated using AUC, accuracy, sensitivity, specificity, F1-score, and G-mean. Differential metabolite screening based on p-values and fold change, together with SHAP-based feature prioritization across multiple machine learning models, was integrated to identify candidate metabolites. The selected metabolites, together with BMI, were then incorporated into a multivariable logistic regression model to construct a nomogram.ResultsNo significant differences in age or sex were observed between groups, whereas BMI was higher in the CaOx group (p < 0.05). Twenty differential metabolites were identified (|log₂FC| > log₂ [1.5], p_adj < 0.05). SHAP analysis consistently highlighted seven metabolites across algorithms. Integration of differential and SHAP-based selection yielded five key metabolites, which, combined with BMI, produced a model with an AUC of 0.8439 (95% CI: 0.8071–0.8806), outperforming any single indicator.ConclusionThis study integrates morning urine organic acid and inorganic ion profiling with machine learning to establish a predictive model for CaOx nephrolithiasis. Five urinary metabolites were identified as potential biomarkers, providing a convenient tool for risk assessment and new insights into CaOx stone pathogenesis.

Background:Multiparametric magnetic resonance imaging (mpMRI) has been widely utilized in clinical practice for identifying clinically significant prostate cancer (csPCa). Although mpMRI demonstrates a pooled negative predictive value (NPV) of 90%, additional clinical parameters require evaluation to enhance this metric specifically for the Chinese population-given the rising incidence of PCa in China, as well as ethnic differences in average prostate volume (PV) and chronic prostatitis prevalence that may impact mpMRI's diagnostic performance. Methods:A retrospective analysis was conducted on 543 patients who underwent transrectal ultrasound-guided prostate biopsy at Beijing Tsinghua Changgung Hospital between November 2014 and March 2025. After applying exclusion criteria, 412 patients were enrolled, all of whom had completed prebiopsy mpMRI within 1 month prior to biopsy. Patients were stratified into four groups based on the results of MRI examination and the pathological outcomes of biopsy: MRI (-) PCa (-), MRI (+) PCa (-), MRI (-) PCa (+), and MRI (+) PCa (+) groups. Multivariate logistic regression analyses were used to assess the odd ratios (ORs) of potential predictors for csPCa, comparing the MRI (-) PCa (+) and MRI (-) PCa (-) groups. Receiver operating characteristic curves were generated to analyze the predictive values of total PSA (tPSA), free PSA (fPSA), free-to-total (f/t) PSA, PV, PSA density (PSAD), and adjusted PSAD (PSADadj, defined as PSAD × weight) for csPCa in patients with negative MRI. Results:The patient distribution was as follows: MRI (-) PCa (-) group: 27.9% (115/412), MRI (+) PCa (-) group: 36.9% (152/412), MRI (-) PCa (+) group: 2.4% (10/412), and MRI (+) PCa (+) group: 32.8% (135/412). The NPV of MRI for csPCa was 92%. Multivariate analyses indicated that PV was negatively associated with the presence of csPCa (OR = 0.940, 95% CI: 0.896-0.986, p = 0.012), while PSAD and PSADadj were positively associated with csPCa occurrence (OR = 10.288, 95% CI: 1.569-67.46, p = 0.015; OR = 1.027, 95% CI: 1.001-1.053, p = 0.043, respectively). For MRI-negative patients, PV > 55.25 mL (sensitivity = 100%, specificity = 63.2%), PSAD < 0.100 ng/mL2 (sensitivity = 100%, specificity = 25.4%), or PSADadj < 7.24 ng/mL (sensitivity = 100%, specificity = 28.1%) enhanced MRI's NPV to 100%, while PSAD < 0.205 ng/mL2 (sensitivity = 77.8%, specificity = 71.9%) and PSADadj < 24.97 ng/mL (sensitivity = 55.6%, specificity = 90.4%) improved NPV to 97.6% and 92.6%, respectively. Conclusion:In Chinese men with negative prostate MRIs, PV > 55.25 mL, PSAD < 0.100 ng/mL2, or PSADadj < 7.24 ng/mL may elevate mpMRI's NPV from 92% to 100%, enabling safe avoidance of unnecessary biopsies. Prospective multicenter validation is required to confirm these findings.

OBJECTIVES:Urinary stone composition critically influences treatment selection and recurrence prevention, yet current intraoperative assessment remains imprecise. This study aims to achieve intraoperative prediction of stone composition by applying a deep convolutional neural network (CNN) to routinely captured endoscopic images. METHODS:We retrospectively studied endoscopic images from stone-breaking surgeries in Beijing Tsinghua Changgung Hospital during 2022-12-2024-12. Images were captured before and after laser lithotripsy. Based on postoperative infrared spectroscopy, stones were divided into five categories. In total, 1780 images (1167 from RIRS, 613 from PCNL) were included and split into training and testing sets at an 8:2 ratio. Using ResNet-50 as the base model, only endoscopic digital images and stone classification data were input for minimal-supervision learning. After training, the model accuracy for each stone category surpassed 95%. The model was then tested on 20% of RIRS and RIRS+PCNL images, with 3D PCA and Grad-cam for visual analysis. RESULTS:For the RIRS image test set: The precision was 93.8% for the calcium oxalate group (n = 147), 96.3% for the calcium oxalate mixed with a uric acid group (n = 30), 91.8% for the calcium oxalate mixed with carbonate apatite group (n = 106), 88.9% for the struvite mixed with calcium oxalate and carbonate apatite group (n = 16), and 100% for the stone free control group (n = 26) (Table 1). Total accuracy for CNN modeling is:94.16%, AUC:0.99, weighted F1-Score: 0.9353, weighted F1-score 95% CI: (0.9089, 0.9599), weighted Kappa: 0.9122, weighted Kappa 95% CI: (0.8523, 0.9569).For the RIRS+PCNL image test set: The precision was 94.9% for the calcium oxalate group (n = 195), 98.7% for the calcium oxalate mixed with a uric acid group (n = 80), 92.2% for the calcium oxalate mixed with carbonate apatite group (n = 111), 100% for the struvite mixed with calcium oxalate and carbonate apatite group (n = 29), and 93.8% for the stone free control group (n = 26) (Table 2).Total accuracy: 95.92%, AUC: 0.99, weighted F1-Score: 0.9508, weighted F1-score 95% CI: (0.9304, 0.9708) weighted Kappa: 0.9357, weighted Kappa 95% CI: (0.8907, 0.9678).The 3D PCA projection results are as follows: PC1: 0.2723 (27.23%), PC2: 0.1102 (11.02%), PC3: 0.0801 (8.01%), Cumulative: 46.26%. CONCLUSIONS:This study shows deep CNNs can identify renal stone compositions from intraoperative endoscopic images, differentiating pure and mixed components. This analysis is an alternative to traditional methods and has the potential to improve treatment effectiveness.

To characterize the relationship between irrigation flow and intrarenal pressure (IRP), and determine the maximum irrigation flow rate for maintaining IRP below threshold of 30 mmHg during retrograde intrarenal surgery (RIRS) with the flexible navigable suction ureteral access sheath (FANS). Fresh ex vivo porcine kidney model were used to establish a manometric system for measuring IRP. IRP was measured through needle tubes punctured into the upper and lower calyces. Flexible ureteroscopes (F-URS) and FANS with varying scope-to-sheath ratios were used to simulate RIRS. The FANS was connected to a vacuum suction device with a suction pressure set at 0.02 MPa (150 mmHg). IRPs were recorded at different irrigation flow rates under no-suction, vent-open, and vent-close conditions, while adjusting the positions of the F-URS and sheath within the kidney. At a scope-to-sheath ratio of 0.716, IRPs exceeded the safe threshold of 30 mmHg at irrigation flow rates of 150 and 250 ml/min under no-suction and vent-open conditions. However, at a flow rate of 300 ml/min, IRPs remained below the safe threshold under vent-closed conditions. At a scope-to-sheath ratio of 0.75, IRPs exceeded 30 mmHg at irrigation flow rates of 150, 250, and 300 ml/min under no-suction, vent-open, and vent-close conditions, respectively. The maximum irrigation flow rate to maintain IRP below the 30 mmHg threshold for the FANS during RIRS increased with the application of negative pressure. Furthermore, under the same negative pressure conditions, the maximum irrigation flow rates decreased as the scope-to-sheath ratio increased.

OBJECTIVE:The pressure fluctuations during retrograde intrarenal surgery (RIRS) can cause related complications, so precise monitoring and control of intrarenal pressure (IRP) play an important role. This study aimed to assess the clinical value of a Chinese-made disposable pressure-measuring flexible ureteroscope in monitoring IRP during RIRS for upper urinary tract stones <2 cm, and analyze factors affecting IRP. METHODS:In this prospective single-arm study, 35 patients (38 renal units) underwent RIRS. Mean age was 42.3 ± 6.1 years, body mass index (BMI) 24.2 ± 2.6 kg/m², and maximum stone diameter 1.6 ± 0.4 cm. Stones were located in the ureter (21.1%), kidney and ureter (15.8%), or kidney only (63.2%). IRP threshold was 30 mmHg; irrigation used gravity or low-pressure pump. Ureteral access sheath (UAS) size (Fr11-13 or Fr12-14) was selected based on ureteroscopy. Outcomes included safe IRP (<30 mmHg), high/maximum IRP, cumulative time above threshold, influencing factors, infection markers, fever incidence, operative time, stone-free rate, and Visual Analogue Scale (VAS) score. RESULTS:All procedures succeeded. Mean safe IRP was 10.9 ± 3.4 mmHg, high IRP 63.6 ± 13.5 mmHg, and maximum IRP 181.2 ± 50.5 mmHg. Mean cumulative time above threshold was 485.2 ± 61.3 s. Low-position UAS placement led to significantly higher high IRP, maximum IRP, and longer high-pressure time compared to conventional placement (all p < 0.05). UAS size did not significantly affect IRP. Postoperative infection markers showed no difference between mean IRP subgroups (0-30 mmHg vs. 30-60 mmHg). Overweight patients had higher mean IRP than normal BMI patients (26.1 ± 4.2 vs. 15.9 ± 5.7 mmHg, p < 0.05). Postoperative fever occurred in 3 cases (8.6%), all with high IRP and prolonged high-pressure exposure. Operative time averaged 45.2 ± 8.3 min, stone-free rate was 92.1%, and mean VAS score was 2.52 ± 0.21. No major complications occurred. CONCLUSIONS:The disposable pressure-measuring flexible ureteroscope enables real-time IRP monitoring during RIRS, allowing surgical strategy adjustments to improve safety. Low UAS position and high BMI are risk factors for elevated IRP.

Background:The existing scoring systems for percutaneous nephrolithotomy fail to adequately consider the influence of renal anatomy, leading to limited predictive accuracy. This study introduces and validates a novel B.T.C.H. nephrolithometry score, designed to better predict stone-free rates and complexity for ultrasound-guided percutaneous nephrolithotomy. Methods:B.T.C.H. nephrolithometry score evaluates four variables including stone burden, type of renal pelvis, calyces involved, and hydronephrosis. 134 patients who underwent ultrasound-guided percutaneous nephrolithotomy at Beijing Tsinghua Changgung Hospital were retrospectively analyzed. The inter-observer agreement was assessed using the linearly weighted kappa coefficient. The accuracy in predicting the stone-free rate was evaluated using receiver operating characteristic curve analysis. Spearman's correlation analysis and Kendall's W test were employed to examine the correlation between the scores of each scoring system and operative time, the number of tracts and CDC scores. Results:The overall stone-free rate was 52.99%. The stone-free rates in low (4-8 points), medium (9-12 points), and high (13-15 points) B.T.C.H. scores were 91.9, 24.6, and 0%, respectively. The B.T.C.H. nephrolithometry score had an AUC of 0.909 for predicting stone-free rate, outperforming both the GSS (AUC = 0.761) and the S.T.O.N.E. nephrolithometry score (AUC = 0.763). The B.T.C.H. nephrolithometry score were positively correlated with operative time, the number of tracts and CDC scores. Conclusion:B.T.C.H. nephrolithometry score is a suggested novel scoring system for ultrasound-guided percutaneous nephrolithotomy, which had superior prediction of stone-free rate and positive correlation with operative time, the number of tracts, and postoperative CDC scores.

This research seeks to evaluate the worldwide burden, health inequities, and projected trends of pediatric urolithiasis from 1990 through 2021. We calculated age-standardized incidence rates, prevalence rates, and disability-adjusted life years rates from the 2021 Global Burden of Disease database. Joinpoint regression was applied for time-trend analysis. Health disparities were measured by using Spearman correlation analysis, Relative Concentration Index, and Slope Index of Inequality. Bayesian Age-Period-Cohort models predicted future global age-standardized incidence rates trends. Global age-standardized incidence rates declined from 79 (95

OBJECTIVE To evaluate the application of Mixed Reality technology in the planning of ultrasoundguided percutaneous nephrolithotomy (PCNL) for special types of complex upper urinary stones. METHODS Clinical data of 15 patients with complex upper urinary stones undergoing ultrasound-guided PCNL were analyzed which included pelvic ectopic kidney, horseshoe kidney, spinal deformity, and transplant kidney. Based on preoperative computed tomography urography (CTU) data, digital 3-dimensional reconstruction is performed, and AI mixed reality is used to project 3dimensional images in real space. This facilitates preoperative design and planning. The consistency rate of target calyx and channel numbers, stone-free rate, total operative time, percutaneous renal access establish time, decrease in hemoglobin level, surgical complications, and postoperative hospital stay are analyzed. RESULTS All patients underwent preoperative planning using mixed reality and successfully completed PCNL. Based on the preoperative planning, we utilized S-PCNL alone or combined with Needle-perc or antegrade/retrograde flexible ureteroscopic surgery. The consistency rate between preoperative planning and intraoperative completion was 87.6%. The stone-free rate was 80%. The average time for establishing the main tract was 2.3 +/- 0.3 minutes, and the average total operative time was 61.5 +/- 12.2 minutes. The mean decrease in hemoglobin level was 9.6 +/- 1.2 g/L, and the average postoperative hospital stay was 4.6 +/- 0.5 days. There were no occurrences of Clavien-Dindo grade >= II complications. CONCLUSION Preoperative quantification and analysis of imaging data through mixed reality enable 3-dimensional visualization and facilitate surgical plans, and effectively avoid the risks of surrounding organ injury in these special urinary stones cases, make complex surgeries smoother and more controllable. UROLOGY 196: 40-47, 2025. (c) 2024 Published by Elsevier Inc.

BACKGROUND:Percutaneous nephrolithotomy is the standard treatment for large or irregularly shaped kidney stones, especially staghorn calculus. However, establishing a precise and safe puncture is challenging and requires extensive training for the surgeon. Navigation surgery is a commonly employed technique that facilitates the puncture through generating a path before surgery. One critical challenge for navigation is skin-kidney path planning due to the complex anatomical deconstruction of the kidney as well as the irregular shape of kidney stones. METHOD:In this paper, we propose a hybrid strategy puncture path planning algorithm, where we follow a 2-step flow path that considers the selection of puncture renal calyces and planning of a B-spine curve path. We imitate the decision-making process of the clinician in selecting the puncture calyx based on the projective area of the calculi to be cleared. We summarize subjective judgment and clinical experience during puncture, where parametric optimization indicators are proposed to realize the optimization of puncture path. RESULTS:An optimal frontier consisting of puncture pathways focused on different puncture factors can be generated from the proposed algorithm, where the physician can choose the path that works best under real circumstances. Results in 2D simulation show that the planned pathway is similar to that planned by a urologist. CONCLUSIONS:The proposed 2-Step hybrid strategy reaches a balance on both optimal effect and efficiency. This automatic planning method based on the long axis section of the kidney can quickly and autonomously provide physicians with a series of optimized puncture paths, and provide auxiliary guidance for clinicians, especially young physicians. Nevertheless, the proposed method shows considerable potential in percutaneous nephrolithotomy surgical demonstration and teaching, and can integrated into robotic surgical navigation system.

Renal tubular injury driven by calcium oxalate (CaOx)-induced oxidative stress constitutes a major contributor to kidney stone formation, while the regulatory role of circRNAs in this process remains poorly characterized. Through high-throughput circRNA sequencing using a calcium oxalate monohydrate (COM)-induced HK-2 cell model, we identified the evolutionarily conserved circEGLN1 as a critical protective factor against oxidative damage. Functional assays in a CaOx nephrolithiasis mouse model and in COM-treated cells, including rescue experiments, demonstrated that circEGLN1 reduces oxidative injury by sequestering miR-212-5p, thereby upregulating STARD7 and mitigating oxidative stress. In vivo experiments revealed that circEGLN1 overexpression attenuates oxidative stress and inhibits crystal deposition in renal tissues via miR-212-5p targeting, providing protection against CaOx-induced injury. RNA fluorescence in situ hybridization analysis of clinical specimens showed significantly lower circEGLN1 expression in stone-containing tissues than in non-stone normal counterparts, indicating its pathophysiological relevance. This study elucidates the circEGLN1/miR-212-5p/STARD7 axis as a novel regulatory mechanism for oxidative injury in nephrolithiasis. These findings not only advance the understanding of ncRNA-mediated renal protection but also highlight circEGLN1 as a promising therapeutic target for preventing CaOx-induced kidney stone formation.

Lightweight triangular mesh models have great potential for real-time 3D visualization of lesions during minimally invasive surgery (MIS). However, the blurred tissue boundaries, high imaging noise, and unoriented points in medical images seriously affect the accuracy and topological quality of surface reconstruction, which can lead to inaccurate lesion localization. In this paper, we present a robust and high-topology-quality triangular mesh reconstruction method that aims to provide a deformable expression model for real-time 3D visualization during surgery. Our approach begins by approximating the model prototype under the guidance of an unsigned distance field by simulating inflation. Then, we introduce a variance-controlled cylindrical domain projection search (VC-CDPS) method to achieve the final surface fitting. Additionally, we incorporate topology optimization into the iterative reconstruction process to ensure smoothness and good topology of the reconstruction model. To validate our method, we conduct experiments on a geometric model with high noise and a human organ model manually segmented by novice doctors. The results demonstrate that our reconstructed model exhibits better surface quality and noise immunity. Furthermore, we conduct a comparison experiment of model deformation and propose a metric to measure the topological quality of the model. Through in vitro tissue experiments, we explored the relationship between topological quality and deformation accuracy. The results reveal a positive correlation between deformation accuracy and topological quality.

Ureteral stenosis is the most common urological condition after renal transplantation that requires extensive technical knowledge and experience in placing thermo-expandable metal stents using a modified rendezvous procedure. The purpose of this study is to analyze the efficacy and safety of this procedure. A total of six female patients underwent a modified rendezvous operation to receive thermo-expandable metal stents between 2022 and 2024. Postoperative follow-up was undertaken for 1 to 24 months. All stents were successfully placed with a mean operative time of 173.0 minutes and an average hospital stay of 8.8 days. Considerable improvements in hydronephrosis were noted among all patients with no statistically significant variation in mean creatinine levels between preoperative and postoperative periods (P = 0.937). Despite a statistical difference in hemoglobin levels between preoperative measurements and those taken on the first postoperative day (P = 0.022), its clinical significance remains unclear. Moreover, we observed no statistically significant difference in preoperative versus postoperative leukocyte counts (P = 0.410). All stents currently remain suitably positioned and functionally stable. In summary, a modified rendezvous procedure in this study demonstrates both safety and efficacy in treating ureteral stenosis after renal transplantation using thermo-expandable metal stents.

Ureteral obstruction is a prevalent urological condition associated with significant complications. The purpose of our study was to assess the safety and efficacy of a novel self-expanding, large caliber, biocompatible polymer-coated ureteral stent (Allium) for the treatment of ureteral obstructions. We conducted a retrospective analysis of data from patients who underwent Allium ureteral stent placement at our institute between November 2018 and May 2023. Demographic, clinical, and perioperative parameters were collected and analyzed. Logistic regression analyses were performed to identify preoperative factors predicting Allium stent migration. The study cohort comprised 30 patients who received a total of 40 successfully implanted Allium stents. No significant adverse events related to the insertion procedure were observed. During a median follow-up period of 29 months (range: 1-60 months), migration occurred in 11 (27.5%) stents while encrustation was noted in 8 (20%) stents. The median functional duration of the Allium stents was found to be 22 months (range:1-60 months), with an overall functioning rate at last follow-up being recorded as 59.5%. Multivariate analysis revealed that the glomerular filtration rate of the ipsilateral kidney was the sole risk factor predictive of Allium stent migration. With its minimal invasiveness and good tolerability, the Allium stent represents a safe and viable management option for treating ureteric obstructions; however, it should not be considered as definitive treatment but rather as an alternative option for patients unwilling or unsuitable for definitive treatment, particularly high-risk individuals or elderly patients exhibiting decreased ipsilateral glomerular filtration rates.

To compare the safety and efficacy of needle-perc-assisted endoscopic surgery (NAES) and retrograde intrarenal surgery (RIRS) for the treatment of 1- to 2-cm lower-pole stones (LPS) in patients with complex infundibulopelvic anatomy. Between June 2020 and July 2022, 32 patients with 1- to 2-cm LPS and unfavorable lower-pole anatomy for flexible ureteroscopy were treated with NAES. The outcomes of these patients were compared with patients who underwent RIRS using matched-pair analysis (1:1 scenario). The matching parameters such as age, gender, body mass index, stone size, hardness, and pelvicalyceal anatomy characteristics including infundibular pelvic angle, infundibular length, and width were recorded. Data were analyzed using the Student’s t-test, Mann–Whitney U test, and Fisher’s exact test. The two groups had similar baseline characteristics and lower-pole anatomy. The stone burden was comparable between both groups. NASE achieved a significantly better initial stone-free rate (SFR) than RIRS (87.5

Objective:To summarize the preliminary clinical experience of utilizing ureteral balloon dilation catheter in the treatment of "difficult ureter" during ureteroscopic lithotripsy, and to discuss the efficacy and safety of the technique.Methods:Clinical data of 28 patients (30 sides) with upper urinary tract calculi admitted to Beijing Tsinghua Changgung Hospital Affiliated to Tsinghua University from April 2021 to July 2022 were retrospectively analyzed. There were 23 males (82.1%) and 5 females (17.9%), with age of (51.5±13.6) years. Among the 30 sides, 20 (66.7%) on the left and 10(33.3%) were on the right. Calculi were either located in the renal pelvis or calyxes in 7 sides (23.3%), upper ureter in 17 sides (56.7%), and lower ureter in 6 sides (20.0%). The maximum diameter of the stones was (9.4±4.2)mm, and 23 sides (76.7%) were combined with hydronephrosis before surgery. When "difficult ureter" was encountered during the procedure, that is, it was difficult to insert ureteroscope or ureteral access sheath (UAS) due to small ureteral lumen, balloon catheter was used for dilation in the first stage, in which the balloon diameter was 4 mm on 22 sides and 5mm on 8 sides. The instrument was retrogradely inserted through the working channel of F8 semi-rigid ureteroscope, and the small site of the ureteral lumen was dilated under direct endoscopic view. After a single dilation, the balloon catheter was withdrawn, and the effect of dilation was evaluated by semi-rigid ureteroscopy to determine whether to proceed with the following procedures. The intraoperative data were recorded, including surgical method, stage of "difficult ureter" occurred, site of the small part of the ureter, related data of utilizing ureteral dilatation balloon catheter, grade of ureteral injury after dilatation (according to the 0-4 grading classification of endoscopic ureteral injuries), total operation time, balloon catheter-related adverse events, stone-free rate, and time of removing ureteral stents.Results:Among the 30 sides, 29 (96.7%) had difficulty in the stage of ureteroscope insertion, and 1(3.3%) had difficulty in the stage of UAS insertion. A total of 37 small sites of ureter were involved, including 18 in the intramural segment, 10 in the lower part, 2 in the middle part, and 7 in the upper part. Each site was dilated once with a median time of 3 (0.5, 5.0) minutes and a median maximum balloon pressure of 1 215.9(1 215.9, 1 443.9)kPa[12.0(12.0, 14.3)atm]. There were 28 sites of grade Ⅰ injury, 8 sites of grade Ⅱinjury, and 1 site of grade Ⅲinjury. The total duration of unilateral procedure was (73.4±30.3) min. Ureteroscope or UAS insertion was successful in 28 sides(93.3%) after balloon dilation, and failed in 2 sides(6.7%), both of which were in the stage of inserting ureteroscope and ureteral stent was indwelled for the second-stage procedures. On the first day after surgery, the hemoglobin level was (134.1±12.9)g/L, which was significantly different from the preoperative parameters ( P<0.01), and serum creatinine level was (86.7±23.2)μmol/L, which showed no significant difference from the preoperative one ( P=0.263). The primary stone-free rate was 92.9% (26/28), and the total postoperative complication rate was 13.3% (4/30), including 3 of grade Ⅰ (lateral lower abdominal pain requiring additional analgesic drugs) and 1 of grade Ⅱ (postoperative hematuria requiring intravenous hemostatic drugs). Follow-up was conducted for 3 months. All of the 28 successful sides had their ureteral stents removed before the last follow-up, and the time of removal was (36.9±11.5) days. No hydronephrosis was found in the ipsilateral kidney by ultrasound 3 months after operation. Conclusions:Balloon dilation technique showed good efficacy and safety in the treatment of "difficult ureter" during ureteroscopic lithotripsy.

The microRNA let-7d has been reported to be a tumor suppressor in renal cell carcinoma (RCC). Tumor-associated macrophages (TAM) are M2-polarized macrophages that can enhance tumor growth and angiogenesis in many human cancers. However, the role of let-7d in TAM-associated RCC progression remains elusive. First, we observed a strongly inverse correlation between let-7d expression and microvessel density in RCC tissues. Furthermore, the proliferation, migration, and tube formation of HUVECs were significantly inhibited by conditioned medium from a coculture system of the phorbol myristate acetate pretreated human THP-1 macrophages and let-7d-overexpressing RCC cells. Moreover, the proportion of M2 macrophages was significantly lower in the group that was cocultured with let-7d-overexpressing RCC cells. Subcutaneous xenografts formed by the injection of let-7d-overexpressing RCC cells together with THP-1 cells resulted in a significant decrease in the M2 macrophage ratio and microvessel density compared with those formed by the injection of control RCC cells with THP-1 cells. In silico and experimental analysis revealed interleukin-10 (IL-10) and IL-13 as let-7d target genes. Importantly, the addition of IL-10 and IL-13 counteracted the inhibitory effects of the conditioned medium from the coculture system with let-7d-overexpressing RCC cells in vitro. Additionally, overexpression of IL-10 and IL-13 reversed the effects of let-7d on macrophage M2 polarization and tumor angiogenesis in vivo. Finally, the expression of IL-10 and IL-13 were inversely correlated with the expression of let-7d in RCC clinical specimens. These results suggest that let-7d may inhibit intratumoral macrophage M2 polarization and subsequent tumor angiogenesis by targeting IL-10 and IL-13.

Purpose To investigate the safety and efficacy of ultrasound-guided renal access and tract dilation using balloon dilators, as well as to identify suitable patients for this technique. Methods Consecutive patients undergoing ultrasound-guided PCNL using balloon dilators between December 2019 and June 2020 in seven large medical centers from China were prospectively enrolled. Demographic and perioperative parameters of the patients were collected. Logistic regression analysis was used to analyze factors that would affect the success rate of tract establishment using ultrasound-guided renal access and balloon dilation. Results A total of 170 patients were included in this study, among whom, 91.18% of the (155/170) patients had a successful tract establishment under ultrasound guidance on the first attempt. The stone-free rate was 83.5% and postoperative complications occurred in 14 patients (8.23%). In univariate analysis, history of ipsilateral surgery (p = 0.026), and stone diameter (p = 0.01) were significantly associated with tract establishment failure, while a larger width of the target calyx (p = 0.016) and the presence of hydronephrosis (p = 0.001) were significantly associated with a successful tract establishment. In multivariate analysis, only hydronephrosis in target calyx (p = 0.027) was a favorable factor for successful tract establishment, and the history of ipsilateral renal surgery (p = 0.012) was the only independent risk factor for failure of tract establishment. Conclusion It was safe and effective to establish percutaneous renal access with balloon dilation under whole-process ultrasound monitoring during PCNL. Furthermore, patients with a hydronephrotic target calyx and without history of ipsilateral renal surgery were most suited to this technique. Trial registration CHiCTR1800014448.