Half-life of serum alpha-fetoprotein in prepubertal testicular yolk sac tumors: an index significantly associated with prognosis.

PURPOSE: To evaluate the association between serum alpha-fetoprotein (AFP) half-life (HL) and prognosis in prepubertal children with elevated AFP values 3 to 4 weeks after surgery for testicular yolk sac tumors (YST). METHODS: Prepubertal patients with testicular YST treated with radical orchiectomy between January 2016 and December 2022 were retrospectively reviewed. Negative outcomes were defined as relapse, metastasis or death. Univariate and multivariate logistic regression analyses were conducted to select risk factors for negative outcomes. RESULTS: A total of 42 patients were eventually enrolled into the study. Patients were divided into non-negative and negative outcomes groups, consisting of 35 and 7 patients, respectively. Thirty-five patients were stage I, two cases were stage II, and five cases were stage IV, according to the Children's Oncology Group staging system. The overall survival (OS) rate was 100%. Average AFP values significantly decreased after resection (P < 0.001). A significant positive correlation was shown between pre- and postoperative AFP values (r = 0.60, P < 0.001). Long AFP HL was considered as an independent risk factor for negative outcomes in YST patients underwent radical orchiectomy (P = 0.04). The cut-off value for AFP HL was 5.78 days, regardless of age division. CONCLUSION: Testicular YST is a relatively rare disease in children with an OS of 100%, and salvage chemotherapy is effective even in grade IV patients. The postoperative AFP HL was significantly associated with prognosis in prepubertal patients with testicular YST. The cut-off value for AFP HL is 5.78 days regardless of the effect of physiological AFP elevation.

Inserting colloidal quantum dots into GaN mesa-array subsurface porous structures through electrochemical etching for display color conversion application.

High-efficiency photon color conversion is an approach of great potential for implementing color display. Inspired by the observation of emission enhancement in a nanoscale cavity, a novel technique to fabricate an array of color converter by mixing colloidal quantum dots (QDs) with the electrolyte of an electrochemical etching (ECE) process is demonstrated. In this process, QDs flow with the electrolyte into the etched subsurface nanoscale porous structure (PS) and settle inside. Since the PS formation and hence QD insertion are controlled by the flow path of the applied electric current in the ECE process, this technique can be used for fabricating any graphic pattern. The nanostructure of such a QD-inserted mesa is examined to confirm QD insertion. Although only single-color mesa arrays are demonstrated in this paper, this technique can be used for fabricating a multiple-color mesa array if a QD or a light-emitting nanoparticle of higher thermal stability is available.

Photon color conversion enhancement of colloidal quantum dots inserted into a subsurface laterally-extended GaN nano-porous structure in an InGaN/GaN quantum-well template.

To improve the color conversion performance, we study the nanoscale-cavity effects on the emission efficiency of a colloidal quantum dot (QD) and the Förster resonance energy transfer (FRET) from quantum well (QW) into QD in a GaN porous structure (PS). For this study, we insert green-emitting QD (GQD) and red-emitting QD (RQD) into the fabricated PSs in a GaN template and a blue-emitting QW template, and investigate the behaviors of the photoluminescence (PL) decay times and the intensity ratios of blue, green, and red lights. In the PS samples fabricated on the GaN template, we observe the efficiency enhancements of QD emission and the FRET from GQD into RQD, when compared with the samples of surface QDs, which is attributed to the nanoscale-cavity effect. In the PS samples fabricated on the QW template, the FRET from QW into QD is also enhanced. The enhanced FRET and QD emission efficiencies in a PS result in an improved color conversion performance. Because of the anisotropic PS in the sample surface plane, the polarization dependencies of QD emission and FRET are observed.

Surface plasmon coupling effects on the photon color conversion behaviors of colloidal quantum dots in a GaN nanoscale hole with a nearby quantum-well structure.

To improve color conversion performance for color display application, we study the near-field-induced nanoscale-cavity effects on the emission efficiency and Förster resonance energy transfer (FRET) under the condition of surface plasmon (SP) coupling by inserting colloidal quantum dots (QDs) and synthesized Ag nanoparticles (NPs) into surface nano-holes fabricated on a GaN template and an InGaN/GaN quantum-well (QW) template. In the QW template, the inserted Ag NPs are close to either QWs or QDs for producing three-body SP coupling to enhance color conversion. Time-resolved and continuous-wave photoluminescence (PL) behaviors of the QW- and QD-emitting lights are investigated. The comparison between the nano-hole samples and the reference samples of surface QD/Ag NP shows that the nanoscale-cavity effect of the nano-hole leads to the enhancements of QD emission, FRET between QDs, and FRET from QW into QD. The SP coupling induced by the inserted Ag NPs can enhance the QD emission and FRET from QW into QD. Its result is further enhanced through the nanoscale-cavity effect. The relative continuous-wave PL intensities among different color components also show the similar behaviors. By introducing SP coupling to a color conversion device with the FRET process in a nanoscale cavity structure, we can significantly improve the color conversion efficiency. Simulation results confirm the basic observations in experiment.

Failure in Double-J stent inserting in laparoscopic pyeloplasty of ureteropelvic junction obstruction: the clinical features and outcomes.

BACKGROUND: Double-J (DJ) stent placement is an important procedure during laparoscopic pyeloplasty (LP). Failing to insert the DJ stent may indicate the patient was also complicated with uretero-vesical junction obstruction (UVJO), and surgeons have to change to another alternative drainage method. In the present study, we analyzed the risk factors of failure of DJ stent placement during the LP and reviewed the clinical outcomes of these challenging pyeloplasties. METHODS: We retrospectively analyzed the clinical data of patients with ureteropelvic junction obstruction (UPJO) who underwent LP in our department from January 2016 to September 2020. For patients who developed a difficult process of inserting the DJ stent, the externalized uretero-pyelostomy (EUP) stent was indwelled. Patients were finally divided into two groups: DJ group and EUP group. The primary outcomes were recurrent UPJO, postoperative uretero-vesical junction obstruction (UVJO) and complications. RESULTS: A total of 535 patients were included in the study, of which 37 patients (6.9%) failed to insert the DJ stent. Age was younger, and weight was lower (P < 0.05) in the EUP group. Within follow-up, recurrent UPJO occurred in ten (1.87%) patients, nine in the DJ group and one in the EUP group (P > 0.05). The incidence of postoperative UVJO in the EUP group was significantly higher than in the DJ group (10.8% vs. 0.2%, P < 0.01). 74 patients (13.8%) developed complications after surgery, 12 patients (32.4%) in the EUP group, significantly higher than that in the DJ group (32.4% vs. 12.4%, P < 0.01). Compared with the DJ group, the larger APD were observed in the EUP group at three months postoperatively (3.50 [3.02;4.58] vs. 2.20 [1.50;2.88], P < 0.05), but the difference vanished in further follow-up. CONCLUSION: The failure of DJ stent placement tends to occur in patients with younger age, lower weight, and larger preoperative APD. Failure may not increase the recurrent UPJO rate, but may indicate a higher probability of postoperative UVJO and may develop more postoperative complications and slower recovery.

Nanoscale-cavity enhancement of color conversion with colloidal quantum dots embedded in the surface nano-holes of a blue-emitting light-emitting diode.

Although the method of inserting colloidal quantum dots (QDs) into deep nano-holes fabricated on the top surface of a light-emitting diode (LED) has been widely used for producing effective Förster resonance energy transfer (FRET) from the LED quantum wells (QWs) into the QDs to enhance the color conversion efficiency, an important mechanism for enhancing energy transfer in such an LED structure was overlooked. This mechanism, namely, the nanoscale-cavity effect, represents a near-field Purcell effect and plays a crucially important role in enhancing the color conversion efficiency. Here, we demonstrate the results of LED performance, time-resolved photoluminescence (TRPL), and numerical simulation to elucidate the nanoscale-cavity effect on color conversion by inserting a photoresist solution of red-emitting QDs into the nano-holes fabricated on a blue-emitting QW LED. Based on the TRPL study of the inserted QDs in a nano-hole structure fabricated on an un-doped GaN template of no QW, it is found that the emission efficiency of the inserted QDs is significantly increased due to the nanoscale-cavity effect. From the simulation study, it is confirmed that this effect can also increase the FRET efficiency, particularly for those radiating dipoles in the QWs oriented perpendicular to the sidewalls of the nano-holes. In the nanoscale-cavity effect, the enhanced near field distribution inside a nano-hole excited by a light emitter modifies its own radiation behavior through the Purcell effect such that its far-field emission becomes stronger.

Enhancement of the Modulation Response of Quantum-Dot-Based Down-Converted Light through Surface Plasmon Coupling.

In this paper, we first elaborate on the effects of surface plasmon (SP) coupling on the modulation responses of the emission of a light-emitting diode (LED) and its down-converted lights through colloidal quantum dots (QDs). The results of our past efforts for this subject are briefly discussed. The discussions lay the foundation for the presentation of the new experimental data of such down-converted lights in this paper. In particular, the enhancement of the modulation bandwidth (MB) of a QD-based converted light through SP coupling is demonstrated. By linking green-emitting QDs (GQDs) and/or red-emitting QDs (RQDs) with synthesized Ag nano-plates via surface modifications and placing them on a blue-emitting LED, the MBs of the converted green and red emissions are significantly increased through the induced SP coupling of the Ag nano-plates. When both GQD and RQD exist and are closely spaced in a sample, the energy transfer processes of emission-reabsorption and Förster resonance energy transfer from GQD into RQD occur, leading to the increase (decrease) in the MB of green (red) light. With SP coupling, the MB of a mixed light is significantly enhanced.

Förster resonance energy transfer in surface plasmon coupled color conversion processes of colloidal quantum dots.

Förster resonance energy transfer (FRET) from a green-emitting quantum dot (GQD) into a red-emitting quantum dot (RQD) is an important mechanism in a multiple-color conversion process, particularly under the surface plasmon (SP) coupling condition for enhancing color conversion efficiency. Here, the dependencies of FRET efficiency on the relative concentrations of GQD and RQD in their mixtures and their surface molecule coatings for controlling surface charges are studied. Also, the SP coupling effects induced by two kinds of Ag nanoparticles on the emission behaviors of GQD and RQD are demonstrated, particularly when FRET is involved in the coupling process. FRET efficiency is reduced under the SP coupling condition. SP coupling can enhance the color conversion efficiency of either GQD or RQD. The combination of SP coupling and FRET can be used for controlling the relative converted light intensities in a multiple-color conversion process.

Central precocious puberty should be taken seriously in children with Leydig cell tumors of the testis after surgical treatment: a tertiary center experience.

ABSTRACT: Central precocious puberty secondary to Leydig cell tumors is rare in children. We retrospectively analyzed the mid- to long-term follow-up data of patients with Leydig cell tumors. The clinical data of 12 consecutive patients who were treated at Beijing Children's Hospital, Capital Medical University (Beijing, China), between January 2016 and October 2023 were retrospectively reviewed. Clinical evaluations, including physical examination, hormone examination, serum tumor marker analysis, abdominal and scrotal ultrasound, chest X-ray, and bone age measurement, were conducted before surgery and at follow-up time points. Surgical approaches were selected according to the individual conditions. Patients with an abnormal hormonal status and suspected of having central precocious puberty were referred to endocrinologists to confirm the diagnosis. Subsequently, gonadotropin-releasing hormone analog therapy was proposed. The mean patient age was 81.3 (range: 40-140) months at the time of the operation. Ten patients had peripheral precocious puberty at admission. All patients had elevated preoperative testosterone levels, whereas tumor marker levels were normal. Testis-sparing surgery was performed in eleven patients, and radical orchiectomy was performed in one patient. The follow-up duration (mean ± standard deviation) was 36.2 ± 25.3 months. Five patients had central precocious puberty, with a mean duration of 3.4 (range: 1-6) months postoperatively. Three patients were receiving gonadotropin-releasing hormone analog therapy, and good suppression of puberty was observed. No risk factors were found for secondary central precocious puberty. There was a high prevalence of central precocious puberty secondary to Leydig cell tumors in our study. Gonadotropin-releasing hormone analog therapy has satisfactory treatment effects. Larger sample sizes and long-term follow-up are needed in future studies.

A dataset on energy efficiency grade of white goods in mainland China at regional and household levels.

To improve energy-saving management, the energy efficiency grade (EEG) was introduced by the Chinese government in the 2000s and mainly implemented for white goods (WGs) in early stages. However, due to the lack of actual statistics, how effective the promotion of high EEG WGs has been in China is still not clear. The China Energy Efficiency Grade (CEEG) of WGs dataset described here comprises (i) EEG-related data on 5 kinds of WGs at the regional (national, provincial) and household levels in China and (ii) predictions of future average EEG trends. By web crawling, retrieving and processing in SQL, the average EEG data weighted by sales in 30 provinces in mainland China from 2012 to 2019 are provided. Household WG survey data, including household information and average EEG, were collected by distributing questionnaires to 1327 households in Beijing, China. The CEEG dataset will facilitate the advancement of research on household energy consumption, household appliance consumer choice, and the assessment of energy efficiency-related policies.

Pairing Electrocarboxylation of Unsaturated Bonds with Oxidative Transformation of Alcohol and Amine.

A parallel paired electrosynthetic method, coupling electrocarboxylation incorporating CO2 into ketone, imine, and alkene with alcohol oxidation or oxidative cyanation of amine, was developed for the first time. Various carboxylic acids as well as aldehyde/ketone or α-nitrile amine were prepared at the cathode and anode respectively in a divided cell. Its utility and merits on simultaneously achieving high atom-economic CO2 utilization, elevated faradaic efficiency (FE, total FE of up to 166 %), and broad substrate scope were demonstrated. The preparation of pharmaceutical intermediates for Naproxen and Ibuprofen via this approach proved its potential application in green organic electrosynthesis.

Residential water and energy consumption prediction at hourly resolution based on a hybrid machine learning approach.

Predicting water and energy consumption at high resolution over a short-term horizon is critical for water and energy resource management. Water and energy are shown to be closely interlinked in household consumption. However, hourly predictions are often based only on historical consumption data for the resource being predicted, with activity or appliance information and household attribution as additional information. Few studies have used aggregated water and energy consumption for predictions. Within this context, the current study proposed a novel hybrid machine learning model based on the Prophet time-series model, Gated Recurrent Unit network, and self-adaptive weights, called the Prophet-GRU model, which could jointly include historical water and electricity consumption as inputs for hourly water or electricity prediction. Data on hourly water and electricity consumption in six households in Beijing during January-March 2020 were used to train and validate the Prophet-GRU model. The goodness of fit indicator (R2) and prediction accuracy (mean squared error and mean absolute error) for the water and electricity predictions were evaluated. Compared with the single input of water or electricity, with the combined input of data of these two resources, the proposed Prophet-GRU model achieved improvements of 29.2 % and 48.5 % in R2, for water and electricity consumption prediction, respectively. Our results could help better understand water-energy linkages and promote collaborative water and energy management practices.

Febrile urinary tract infection after Double-J stent removal is associated with restenosis after laparoscopic pyeloplasty: A propensity score matched analysis of 503 children.

OBJECTIVE: To analyze the association between the febrile urinary tract infection (fUTI) after Double-J (DJ) stents removal and restenosis after laparoscopic pyeloplasty (LP). STUDY DESIGN: We retrospectively reviewed the clinical data of patients who were treated with transperitoneal LP for ureteropelvic junction obstruction from 2016 to 2020. Patients were divided into two groups according to whether they developed fUTI after DJ stent removal within 48 h. The 1:3 Propensity Score Matched (PSM) method was used to balance confounding variables. RESULTS: 503 patients were included in the study. 28 (5.57%) patients developed fUTI after DJ stent removal. Compared with the non-fUTI group, age was younger, and weight was lower (P < 0.05) in the fUTI group. Restenosis occurred in 11 (2.2%) patients, of which six patients developed fUTI after DJ stent removal. The revision surgery rate in the fUTI group was significantly higher than in the non-fUTI group (21.4% vs. 1.1%, P < 0.01). After PSM, the results remained consistent. For 492 patients without restenosis, 22 patients developed fUTI. Compared with the non-fUTI group, the larger anteroposterior diameter (APD) and higher APD/cortical thickness (P/C) ratio were observed in the fUTI group at three months and six months postoperatively (P < 0.05), but the difference vanished at 12 months and 24 months after surgery (Figure). DISCUSSION: FUTI after DJ stent removal is not uncommon after LP, and surgeons are often concerned about the possibility of restenosis. In the present study, although our results demonstrated a significant association between them, restenosis patients comprise only about 20% of fUTI patients. Based on our clinical observations, fUTI is often developed in children from 1 to 6 years of age, and the younger patients may be afraid of voiding because of the postoperative pain after DJ stent removal. Besides, intraoperative manipulation of DJ stent removal may lead to transient edema in the anastomotic site, causing the fUTI. For patients who develop fUTI after DJ stent removal but without persistent symptoms, the transient worsening of hydronephrosis during the early postoperative period may not impact long-term outcomes (As shown in Figure). Additional follow-up is needed to prevent the deterioration of renal function. CONCLUSIONS: Our result demonstrated that fUTI after DJ stent removal is associated with restenosis after LP. For fUTI patients without restenosis, APD and P/C ratio exhibited transient worsening at three months and six months postoperatively, decreasing gradually during follow-up. Patients who develop fUTI after DJ stent removal should be monitored.

A radiomics nomogram for preoperative prediction of nephron-sparing surgery in patients with bilateral Wilms tumor.

Background: Bilateral Wilms tumor (BWT) is a relatively rare malignant renal tumor in children. Nephron-sparing surgery (NSS) is the preferred surgical approach for treating BWT, but lacks uniform surgical indications worldwide. This study aimed to summarize the clinical and imaging features of BWT children, establish a radiomics nomogram, and predict the feasibility of NSS for improving outcomes. Methods: A 12-year retrospective single-center review was conducted on clinical data and preoperative imaging features of BWT patients. The tumor kidneys were divided into NSS and non-NSS groups. Logistic regression analysis was performed to identify independent predictors and develop a prediction model of the feasibility of NSS in BWT patients. A radiomics nomogram was constructed and internally validated by the parametric bootstrapping method. Results: A total of 58 BWT patients (115 renal units) were included in this study. After evaluations based on preoperative imaging and clinical data, 94 renal units underwent NSS with negative resection margins and were included in the NSS group, whereas 16 renal units with positive resection margins, macroscopic residual, or total nephrectomies were included in the non-NSS group. Tumor size [odds ratio (OR): 0.540, 95% confidence interval (CI): 0.308-0.945], relationship with the collecting system (OR: 0.013, 95% CI: 0.0004-0.370), and remaining renal parenchyma (RRP) proportion (OR: 71.23, 95% CI: 1.632-3108.8) were identified as independent predictors for NSS. A nomogram was constructed based on these factors, which demonstrated great consistency between the predicted and observed feasibility of NSS. The model presented with good discriminative ability [area under the curve (AUC), 0.982]. The decision curve analysis (DCA) revealed the clinical usefulness of the model. Conclusions: This study analyzed the clinical and preoperative imaging data of BWT patients and identified three independent predictors for the feasibility of NSS, including tumor size, relationship with the collecting system, and residual renal parenchyma proportion. The radiomics nomogram established in this study can provide individualized predictions to assist clinicians in making better decisions and improving patient outcomes.

Effectiveness of penile ventral curvature correction and the trend of hypospadias repair: a prospective study of the national center in China.

BACKGROUND: Hypospadias repair is a complex surgical procedure that involves correcting penile ventral curvature (VC) and performing urethroplasty. This study aims to evaluate the effectiveness of different strategies for VC correction and analyse the trends in hypospadias repair at a national centre in China. METHODS: Prospective data collection was conducted from 2019 to 2020 for patients undergoing hypospadias repair. The effectiveness of VC correction was assessed based on the degree of VC change with different strategies. Furthermore, the choice of surgical techniques for different types of hypospadias repair was analysed. RESULTS: A total of 434 patients were included, with a median preoperative VC degree of 50° (35°, 70°). All patients achieved a straight penis postoperatively, with 15.2% undergoing degloving, 28.6% undergoing degloving and dorsal plication (DP), 13.1% undergoing degloving and urethral plate transection (UPT), and 43.1% undergoing degloving, UPT and DP. Degloving alone was effective in correcting VC in 57.6% of patients with VC less than 30°. In our analysis, DP after UPT resulted in a higher degree of correction (25°) compared with DP after degloving alone (20°) (p<0.001). The study identified the current trends in hypospadias repair, with tubularised incised plate urethroplasty (TIP) being the most common technique used in distal hypospadias repair (70.6% of patients) and transverse preputial island flap urethroplasty (TPIFU) being preferred for proximal hypospadias repair (63.0%). CONCLUSIONS: Degloving alone is effective for correcting VC less than 30°. The majority of patients in our centre underwent UPT, and DP after UPT yielded better results compared with DP after degloving alone. Distal hypospadias repair commonly used TIP, while TPIFU was favoured for proximal hypospadias repair. TRIAL REGISTRATION NUMBER: ChiCTR1900023055.

Reoperation frequency after transverse preputial Island flap urethroplasty "Duckett's technique" in treatment of severe hypospadias: A single center study.

Purpose: Transverse Preputial Island Flap Urethroplasty (TPIFU) is one of the most common techniques for treating severe hypospadias. Studies on the reoperation frequency after TPIFU is lacking. In the present study, we reported our clinical outcomes of severe hypospadias treated with one-staged TPIFU and analyzed the operation frequency. Methods: We retrospectively analyzed the clinical data of severe hypospadias patients who underwent one-stage TPIFU from December 2018 to December 2019 in the department of Urology at Beijing Children's Hospital. A stepwise approach was used to manage the curvature. Severe hypospadias was defined as those residual curvature was higher than 30° after degloving. Urethroplasty complications included fistula, urethral stricture, and diverticulum. The short-term cure was identified as no complications occurring for 12 months after the date of last-time surgery. The reoperation rate and operation frequency of TPIFU were analyzed. Results: A total of 136 patients who underwent one-stage TPIFU were included in the study. The follow-up after primary urethroplasty ranged from 22 to 50 months. The median age at primary surgery was 22.5 months (range from 13 to 132 months). After primary TPIFU surgery, 53 (39%) patients underwent additional surgical interventions to treat postoperative complications. Among them, 24 patients (17.6%) developed fistula, 17 patients (12.5%) developed urethral stricture and 11 patients (8.1%) developed diverticulum. After the second surgery, five patients remained fistula, five patients remained urethral stricture, and seven patients remained diverticulum. Overall, 61% (85 patients) met the cured standard after the primary operation, and the two operations cure rate was 87.5% (119 patients). 91.2% (124 patients) were cured in three operations. Conclusions: Although the complication rates after primary TPIFU were relatively high, more than half of patients achieved short-term cured through a single operation, and the cure rate after two or three operations was acceptable.

Development of the prediction model for negative outcomes after primary laparoscopic pyeloplasty in children: a retrospective study of 535 patients.

Background: Laparoscopic pyeloplasty (LP) has been widely accepted as an effective method to treat ureteropelvic junction obstruction (UPJO) in pediatric patients. Limited studies focused on the relationship between risk factors and negative outcomes. Our study aimed to seek independent risk factors for negative outcomes and construct a prognostic nomogram to assist clinical decision-making and improve outcomes. Methods: A total of 535 patients with UPJO treated with primary LP between January 2016 and December 2020 were retrospectively reviewed. Negative outcomes were defined as restenosis requiring reoperation and grade III and IV complications based on the Clavien-Dindo grading system. Univariate and multivariate logistic regression analyses were used to select risk factors for negative outcomes after LP and developed the prediction model. The model was internally validated by the parametric bootstrapping method. Results: Among the 535 patients, 33 (6.2%) developed negative outcomes. Ten patients developed ureteropelvic junction (UPJ) restenosis and underwent secondary surgery. UPJ leakage (two cases), difficulty of urinating after the removal of the Double-J (DJ) stent (two cases), and ileus (two cases) were the most common grade IIIa complications, while distal ureteral stricture (five cases), hernia formation (three cases), and delayed wound healing around the fistula (two cases) were the most common grade IIIb complications. After univariate and multivariate logistic analyses, the patient's weight, preoperative anteroposterior pelvic diameter (APD), and difficulty of DJ stent insertion were independent risk factors for negative outcomes, and they were used to fit the prediction model. The Brier score was 0.048. The model was relatively well-calibrated. The area under the receiver operating characteristic curve was 0.831 (95% CI: 0.756-0.906). Decision curve analysis illustrated good clinical utility. Conclusions: Primary LP is a safe and effective method for pediatric patients with UPJO. The patient's weight, preoperative APD, and difficulty of DJ stent insertion were independent risk factors for negative outcomes after LP. We established and validated a predictive model for negative outcomes after LP. With the help of this model, clinicians can make better decisions and improve patient outcomes.

Redo laparoscopic pyeloplasty for recurrent ureteropelvic junction obstruction: Propensity score matched analyses of a high-volume center.

Purpose: Review the experience of redo laparoscopic pyeloplasty (RLP) in patients with recurrent ureteropelvic junction obstruction (UPJO) in comparison to primary laparoscopic pyeloplasty (PLP) and redo open pyeloplasty (ROP), and determine the feasibility and effectiveness of RLP for recurrent UPJO in children. Methods: We retrospectively reviewed the clinical data of patients treated with transperitoneal PLP, RLP, and ROP for UPJO from December 2015 to December 2022. The Propensity score matching (PSM) was used to balance confounding variables. RLP patients were 1:4 matched with PLP and 1:3 matched with ROP. The primary outcomes were failure and post-operative complications. Complications were classified according to the Clavien-Dindo grading system. Results: The study included ten patients who underwent RLP, 43 patients who underwent ROP, and 412 patients who underwent PLP. The follow-up time ranged from 6 to 36 months in the RLP group, 12 to 60 months in the PLP group, and 24 to 54 months in the ROP group. In the RLP group, no failure but three post-operative complications (Clavien grade II) were observed during the follow-up. Compared with the PLP group, the older age, higher weight, larger pre-operative anteroposterior diameter (APD) and APD/cortical thickness (P/C ratio), longer operation time, and post-operative length of stay (LOS) in the RLP group (P < 0.05). After PSM, longer operation time and post-operative LOS were observed in the RLP group (P < 0.05). Compared with the ROP group, the older age, higher weight, and longer post-operative LOS in the RLP group (P < 0.05). After PSM, longer post-operative LOS was observed in the ROP group (P < 0.05). The failure and complication rates were comparable between RLP and PLP or RLP and ROP (P > 0.05). Conclusions: Our result demonstrated that RLP performed as well as PLP except for a longer operation time. Compared with ROP, RLP has the advantages of a clearer surgical view, sufficient exposure, clearer anatomical landmark position, and minor trauma with a comparable clinical outcome. On experienced hands, RLP for recurrent UPJO after is a safe and effective procedure and should be considered an excellent alternative to the more commonly recommended ROP in select patients.

Do China's coal-to-gas policies improve regional environmental quality? A case of Beijing.

Clean energy transition has been considered as an indispensable way to attain sustainable development for China, where the coal-to-gas initiative plays a vital role towards the goal. This paper takes Beijing, China's political and economic center as well as a national pioneer in the energy transition, as a case to systematically analyze the co-mitigation of air pollution (PM2.5) and carbon emissions (CO2) achieved by the policy-driven natural gas-coal consumption substitution. Firstly, a qualitative analysis of the relationship of Beijing's coal-to-gas policies and its air quality has been conducted. Then, VAR and ARDL models are employed to quantitatively analyze the impacts of coal-to-gas policies on PM2.5 and CO2, respectively. Results show that (i) an innovation of natural gas/coal consumption ratio will reduce PM2.5 concentrations, and the effect decreases over time; and (ii) an increase of 1% in natural gas/coal consumption ratio in Beijing will cause a decrease of 0.0784% in CO2 emissions in the long run. Therefore, the coal-to-gas policies do increase the usage of natural gas and improve Beijing's air quality. The assessment methods and conclusions can be regarded as a reference for not only China's policymakers, but also other countries, especially nowadays when air quality is becoming more valued and GHGs are being tightly controlled.

Development and validation of a preoperative nomogram for predicting positive surgical margins after laparoscopic radical prostatectomy.

BACKGROUND: Positive surgical margins are independent risk factor for biochemical recurrence, local recurrence, and distant metastasis after radical prostatectomy. However, limited predictive tools are available. This study aimed to develop and validate a preoperative nomogram for predicting positive surgical margins after laparoscopic radical prostatectomy (LRP). METHODS: From January 2010 to March 2016, a total of 418 patients who underwent LRP without receiving neoadjuvant therapy at Peking University Third Hospital were retrospectively involved in this study. Clinical and pathological results of each patient were collected for further analysis. Univariable and multivariable logistic regression (backward stepwise method) were used for the nomogram development. The concordance index (CI), calibration curve analysis and decision curve analysis were used to evaluate the performance of our model. RESULTS: Of 418 patients involved in this study, 142 patients (34.0%) had a positive surgical margin on final pathology. Based on the backward selection, four variables were included in the final multivariable regression model, including the percentage of positive cores in preoperative biopsy, clinical stage, free prostate specific antigen (fPSA)/total PSA (tPSA), and age. A nomogram was developed using these four variables. The concordance index (C-index) of the nomogram was 0.722 in the development cohort and 0.700 in the bootstrap validations. The bias-corrected calibration plot showed a limited departure from the ideal line with a mean absolute error of 2.0%. In decision curve analyses, the nomogram showed net benefits in the range from 0.2 to 0.7. CONCLUSION: A nomogram to predict positive surgical margins after LRP was developed and validated, which could help urologists plan surgical procedures.