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The creation of synthetic reservoirs for bladder replacement has been limited by challenges of interfacing synthetic materials and native tissue. We sought to overcome this challenge by utilizing a novel bilayer silk fibroin scaffold (BLFS) as an intermediary towards the development of an acellular prosthetic reservoir.Under institutionally-approved protocols, 3D-printed reservoirs were implanted in six juvenile female pigs after cystectomy. BLFS was attached to the in-situ prosthetic reservoir serving as an intermediary to native ureteral and urethral tissue anastomoses. Our first protocol allowed four pigs to be survived up to seven days, and the second protocol allowed two pigs to be survived for up to one year. At the first sign of functional decline or the end of the study period, the animals were euthanized, and kidneys, ureters, prosthetic bladder, and urethra were harvested en-bloc for histopathology.The first two pigs had anastomotic urine leaks due to design flaws resulting in early termination. The third pig had acute renal failure resulting in early termination. The artificial bladder design was modified in subsequent iterations. The fourth pig survived for seven days and upon autopsy, had intact urethral and ureteral anastomoses. The fifth and sixth pigs survived for 11 and 12 weeks, respectively, before they were sacrificed due to failure to thrive. One animal developed an enteric fistula. The other animal had an intact anastomosis, and the BLFS was identified at the ureteral and urethral anastomoses on histopathogic analysis.Replacing the porcine bladder with a prosthetic bladder was successfully achieved for up to three months, the second longest survival period for a nonbiological bladder alternative. Bilayer silk fibroin scaffold was used for the first time to create an interface between synthetic material and biologic tissue by allowing ingrowth of urothelium onto the acellular alloplastic bladder.

INTRODUCTION AND OBJECTIVES Conventional renal stone dusting is challenging; the holmium laser (Ho:YAG) and holmium with MOSES Effect (Ho:YAG-MOSES) fail to uniformly produce fragments

Although percutaneous nephrolithotomy (PCNL) is less morbid than open surgery, it still carries risks of significant complications as well as injury to the renal parenchyma. Flexible ureteroscopic stone removal, although causes no appreciable damage to the renal parenchyma, has limitations, most notably, a lower stone-free rate than PCNL. Advances in our knowledge regarding ureteral physiology combined with technical developments applied to ureteral access sheath deployment and size may well propel retrograde intrarenal surgery to the forefront of kidney stone removal, regardless of stone size or location.

Introduction: We sought to examine the intrarenal fluid and tissue temperature alterations during dusting and fragmentation with the thulium fiber laser (TFL) in an in vivo porcine kidney. Material...

We sought to compare the effectiveness and efficiency of the superpulse thulium fiber laser (sTFL to the holmium laser (Ho:YAG) for ureteroscopic "dusting" of implanted renal stones in an in-vivo porcine model.Twenty-four porcine kidneys (12 juvenile female Yorkshire pigs) were randomized to Ho:YAG or sTFL treatment groups. Canine calcium oxalate stones were scanned with computed tomography to calculate stone volume and stone density; the stones were randomized and implanted into each renal pelvis via an open pyelotomy. In all trials, a 14Fr, 35 cm ureteral access sheath was placed. With a 9.9F dual lumen flexible ureteroscope, laser lithotripsy was performed using dusting settings: Ho:YAG 200µm laser fiber at 16W (0.4J, 40Hz) or sTFL 200µm laser fiber at 16W (0.2J, 80Hz). Lithotripsy was continued until no fragments over 1mm were observed. No stone basketing was performed. Throughout the procedures, intra-renal and renal pelvis temperatures were measured using two percutaneously positioned K-type thermocouples, one in the upper pole calyx and one in the renal pelvis. After the lithotripsy, the ureteropelvic junction was occluded, the kidneys were bi-valved and all residual fragments were collected, dried, weighed, and then measured with an optical laser particle sizer.Implanted stones were similar in volume and density in both groups. Intraoperative collecting system temperatures were similar for both groups (all44ºC). Compared to Ho:YAG, sTFL ablated stones faster (9min vs. 27min, p0.001) with less energy expenditure (8kJ vs. 26kJ, p0.001), and a greater stone clearance rate (73% vs. 45%, p=0.001). After sTFL lithotripsy, 77% of the remaining fragments were ≤1 mm versus 17% of fragments ≤1 mm after Ho:YAG treatment (p0.001).In an in-vivo porcine kidney, using dusting settings, sTFL lithotripsy resulted in shorter ablation times, higher stone clearance rates, and markedly smaller stone fragments than Ho:YAG lithotripsy.

Background. It is often tricky to differentiate cystic pituitary adenoma from Rathke cleft cyst with visual inspection because of similar MRI presentations between them. We aimed to design an MR-based radiomics model for improving differential diagnosis between them. Methods. Conventional diagnostic MRI data (T1-,T2-, and postcontrast T1-weighted MR images) were obtained from 215 pathologically confirmed patients (105 cases with cystic pituitary adenoma and the other 110 cases with Rathke cleft cyst) and were divided into training ( n = 172 ) and test sets ( n = 43 ). MRI radiomics features were extracted from the imaging data, and semantic imaging features ( n = 15 ) were visually estimated by two radiologists. Four classifiers were used to construct radiomics models through 5-fold crossvalidation after feature selection with least absolute shrinkage and selection operator. An integrated model by combining radiomics and semantic features was further constructed. The diagnostic performance was validated in the test set. Receiver operating characteristic curve was used to evaluate and compare the performance of the models at the background of diagnostic performance by radiologist. Results. In test set, the combined radiomics and semantic model using ANN classifier obtained the best classification performance with an AUC of 0.848 (95% CI: 0.750-0.946), accuracy of 76.7% (95% CI: 64.1-89.4%), sensitivity of 73.9% (95% CI: 56.0-91.9%), and specificity of 80.0% (95% CI: 62.5-97.5%) and performed better than multiparametric model ( AUC = 0.792 , 95% CI: 0.674-0.910) or semantic model ( AUC = 0.823 , 95% CI: 0.705-0.941). The two radiologists had an accuracy of 69.8% and 74.4%, respectively, sensitivity of 69.6% and 73.9%, and specificity of 70.0% and 75.0%. Conclusions. The MR-based radiomics model had technical feasibility and good diagnostic performance in the differential diagnosis between cystic pituitary adenoma and Rathke cleft cyst.

Purpose:Ureteral injury is a frequent complication of ureteral access sheath deployment. We sought to define the safe threshold of force for the passage of a ureteral access sheath using a novel ur...

Objective: It has been previously reported that warming irrigation fluid higher than body temperature may decrease ureteral spasm and thereby facilitate ureteroscopic access to the proximal ureter....

Introduction: The advent of single-use disposable flexible ureteroscopes allows for rapid prototyping of novel endoscopes. In this regard, we sought to develop a female-specific ureteroscope, with ...

Many major guidelines across the globe address the medical and surgical management of urolithiasis. We elected to compare and contrast the recommendations among the 5 most highly cited guidelines on stone disease to offer insights on where evidence has created a consensus and where there remains ongoing controversy and hence a need for the pursuit of studies that will provide a higher level of evidence.We reviewed the American Urological Association 2019 medical and 2016 surgical guidelines, the 2016 Canadian Urological Association guidelines, the 2020 European Association of Urology guidelines, the 2019 National Institute for Health and Care Excellence and the 2019 Urological Association of Asia guidelines. Tables correlating guideline statements by topic were created, and a comparative analysis was conducted to ascertain consensus and discordance.Comparative analysis of recommendations from the American Urological Association guidelines to the Canadian Urological Association, European Association of Urology, National Institute for Health and Care Excellence guidelines and Urological Association of Asia revealed a high consensus surrounding the medical management of stones. In terms of the surgical management of stones, there is high consensus regarding the treatment of ureteral stones including medical expulsive therapy using alpha blockers, not prestenting for uncomplicated ureteroscopy and employment of either ureteroscopy or shockwave lithotripsy as first line treatment. There is high consensus among the American Urological Association, European Association of Urology, National Institute for Health and Care Excellence and Urological Association of Asia guidelines regarding renal stone treatment. The Canadian Urological Association does not have guidelines on the management of renal stones. Unlike the American Urological Association and National Institute for Health and Care Excellence, the Canadian Urological Association and European Association of Urology make specific recommendations regarding selection of patients for shockwave lithotripsy procedures, including stone density, skin-to-stone distance, treatment rate, acoustic coupling and postshockwave lithotripsy use of medical expulsive therapy.There are many areas of consensus and only minor areas of conflict among the most up-to-date American Urological Association, Canadian Urological Association, European Association of Urology, National Institute for Health and Care Excellence and Urological Association of Asia guidelines on the medical and surgical management of stone disease. Conflicts among guidelines and areas of low evidence, such as followup imaging strategies and stone surveillance, the use of a ureteral access sheath in ureteroscopy and guidance on the use of miniaturized percutaneous nephrolithotomy, are opportunities for novel, impactful high grade clinical studies.

An actively Q-switched all-solid-state YVO4 Raman laser, which used a 885-nm side-pumped Nd:YAG laser as the fundamental wavelength and delivered yellow output, is demonstrated. An in-band pump scheme is adopted to mitigate the thermal effects in the laser crystal and a Z-shaped laser cavity is used to compensate thermal lensing further. By intracavity frequency doubling of the Stokes wave with KTP crystal, 13.7-W yellow output at a wavelength of 588 nm, with a pulse repletion frequency of 10 kHz, was obtained under a diode pump power of 233 W. Additionally, single-pulse energy was 1.37 mJ with the pulse-width of 12.5 ns, corresponding to a peak power of 110 kW.

MgNb2O6 ceramics doped with (Li2O–MgO–ZnO–B2O3–SiO2) glass were synthesized by the traditional solid phase reaction route. The effects of LMZBS addition on microwave dielectric properties, grain growth, phase composition and morphology of MgNb2O6 ceramics were studied. The SEM results show dense and homogeneous microstructure with grain size of 1.72 μm. Raman spectra and XRD patterns indicate the pure phase MgNb2O6 ceramic. The experimental results show that LMZBS glass can markedly decrease the sintering temperature from 1300 °C to 925 °C. Higher density and lower porosity make ceramics have better dielectric properties. The MgNb2O6 ceramic doped with 1 wt% LMZBS glass sintered at 925 °C for 5 h, possessed excellent dielectric properties: er = 19.7, Q·f = 67 839 GHz, τf = −41.01 ppm °C−1. Moreover, the favorable chemical compatibility of the MgNb2O6 ceramic with silver electrodes makes it as promising material for low temperature co-fired ceramic (LTCC) applications.

Exploration of noble-metal-free, highly-efficient and durable catalysts for Hydrogen evolution reaction (HER) remains a challenge. In this work, the development of carbon-coated cobalt-molybdenum-phosphide nanosheets supported on carbon cloth (Co-Mo-P@C) is successfully demonstrated. To obtain a better electrocatalystic performance, the different amount of glucose was added into the reaction system during hydrothermal process. Benefiting from the 2D structure, high electrical conductivity and sufficient active sites, the Co-Mo-P@C contained 0.5 mmol glucose exhibits relatively good catalytic activity for HER with low over poentials at −96 mV and −162 mV @ 10 mA cm−2 in acidic and alkaline medias respectively and the Tafel slope of 52.9 mV dec−1 and 34.3 mV dec−1. Additionally, the catalyst also shows good durability in the both electrolytes.

The linear demodulation range and background noise of the Michelson interferometer system are investigated with a laser phase noise measurement system. We have theoretically and experimentally analyzed the performance of the interferometer system by changing the frequency modulation amplitude of the laser and the optical path difference (OPD) of the interferometer, respectively. It is shown that the linear demodulation range of the Michelson interferometer system is finite, which depends on the parameters of the system, such as the sample frequency, the delay time between two interferometer arms, and the system bandwidth. Furthermore, the experimental results indicate that the background noise of the interferometer system can be reduced by using a sufficiently long OPD so that the smaller true phase information can be detected with the demodulation system. The parameters of the measurement system could be optimized to satisfy the demand of the phase demodulation with different levels, which is of great significance for the phase monitoring interrogator, such as fiber-optical interferometer sensors and distributed acoustic sensors.

Although percutaneous nephrolithotomy (PCNL) is less morbid than open surgery, it still carries risks of significant complications as well as injury to the renal parenchyma. Flexible ureteroscopic stone removal, although causes no appreciable damage to the renal parenchyma, has limitations, most notably, a lower stone-free rate than PCNL. Advances in our knowledge regarding ureteral physiology combined with technical developments applied to ureteral access sheath deployment and size may well propel retrograde intrarenal surgery to the forefront of kidney stone removal, regardless of stone size or location.

INTRODUCTION AND OBJECTIVE:Kidney stone composition is becoming increasingly important in treatment algorithms as the composition/hardness of stones impacts treatment success. Artificial intelligen...

INTRODUCTION AND OBJECTIVE:Ureteral access sheaths (UAS) are used during ureteroscopy to facilitate passage of the ureteroscope and the extraction of renal and ureteral stone fragments. Larger UAS ...

The goal of this paper is to evaluate the use of an office-based renal mass biopsy (RMB), whose feasibility could represent a paradigm shift in clinical practice. Despite the earlier diagnosis of patients with renal masses, the lack of evidence showing a reduction in cancer-specific mortality warrants an examination in treatment practices. RMB is underutilized when compared to biopsy practice for all other neoplasms in every other solid organ (except testis), and the majority of RMB performed are outsourced to interventional radiologists. Performing an ultrasound-guided, office-based RMB is safe, reproducible, and has a meaningful impact on management decisions. The use of percutaneous RMB in clinical practice is growing, and the use of RMB has meaningful impact on management decisions for renal masses. Incorporating ultrasound-guided biopsy of a renal mass into clinical practice is feasible, and in contemporary practice, the urologist has the skill set to perform the procedure reliably, with low morbidity, and with minimal patient discomfort.

Electrochemical hydrogen evolution reaction (HER) from water splitting is a promising way to promote the utilization of renewable energy. Designing and fabricating electrocatalysts with low cost, high catalytic activity and robust stability is desirable. In response, we prepared carbon shells encapsulating ultrafine β-Mo2C nanoparticles with N and P dual-doping as advanced electrocatalyst used for HER in both acidic and alkaline mediums. This paper gives a discussion on element doping and porosity which have influence on the HER performance. As introducing heteroatoms into carbon matrix to create active sites and enhance electron transfer capacity, the as-prepared electrocatalyst exhibits high catalytic activity with low overpotential of 117 mV and 121 mV to achieve current density of 10 mA cm−2 in acidic and alkaline solutions. Due to the strategy of carbon shells encapsulating, the catalyst presents robust stability for a long time at various applied potential. Furthermore, the design idea of using multiple strategies preparing catalysts may serve some inspiration to fabricate advanced electrocatalysts.