Mechanical Properties of Railway High-strength Manufactured Sand Concrete: Typical Lithology, Stone Powder Content and Strength Grade

In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand lithology(tuff,limestone,basalt,granite),stone powder content(0,5%,10%,15%)and concrete strength grade(C60,C80,C100)as variables.The evolution of mechanical properties of HMC and the correlation between cubic compressive strength and other mechanical properties are studied.Compared to river sand,manufactured sand enhances the cubic compressive strength,axial compressive strength and elastic modulus of concrete,while its potential microcracks weaken the flexural strength and splitting tensile strength of concrete.Stone powder content displays both positive and negative effects on mechanical properties of HMC,and the stone powder content is suggested to be less than 10%.The empirical formulas between cubic compressive strength and other mechanical properties are proposed.

Role of variation coefficient of stone density in determining success of shock wave lithotripsy in urinary calculi

BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes.

PbrMYB4,a R2R3-MYB protein,regulates pear stone cell lignification through activation of lignin biosynthesis genes

Pear(Pyrus bretschneideri)fruit stone cells are primarily composed of lignin and have strongly lignified cell walls.The presence of stone cells has a negative influence on fruit texture and taste,and thus the reduction of stone cell content in pear fruit is a key goal of breeding efforts.However,research into the key transcription factors and regulatory networks associated with pear fruit stone cell formation have been limited.We here used a combination of co-expression network and expression quantitative trait locus(eQTL)analyses in 206 pear cultivars with different stone cell contents to identify relevant genes;these analyses uncovered the gene PbrMYB4,a R2R3 MYB transcription factor gene.There was a strong positive correlation between relative PbrMYB4 expression levels in the fruit flesh and stone cell/lignin contents.Overexpression of PbrMYB4 significantly increased the lignin contents,whereas silencing of PbrMYB4 had the opposite effect,decreasing the contents of lignin.PbrMYB4 overexpression in pear calli significantly promoted lignin biosynthesis.In Arabidopsis thaliana,PbrMYB4 overexpression resulted in increasing lignin deposition,cell wall thickness of vessels and xylary fiber,and accelerating expression level of lignin biosynthetic genes.PbrMYB4 was found to activate 4-Coumarate:Coenzyme A Ligase(Pbr4CL1)by binding to AC-I elements in the promoter regions,as demonstrated with dual-luciferase reporter assays and a yeast one-hybrid assay.These results demonstrated that PbrMYB4 positively regulated lignin biosynthesis in pear fruit stone cells by activating lignin biosynthesis genes.This study improves our understanding of the gene regulatory networks associated with stone cell formation in pear fruit,providing guidance for molecular breeding of pear varieties with low stone cell content.

Critical assessment of the reported bidirectional associations between gallstone, non-alcoholic fatty liver, and kidney stone diseases

The recent article by Jiang et al published in World Journal of Gastroenterology reports substantial bidirectional associations between gallstone disease(GSD),non-alcoholic fatty liver disease(NAFLD),and kidney stone disease(KSD),based on multicenter cross-sectional studies and a systematic review with meta-analysis.While the findings have the potential to significantly impact clinical and pre-ventive strategies,several methodological issues merit closer examination.This letter critiques key aspects of the study,including sample population hetero-geneity,potential confounding variables,and the reliance on cross-sectional data that may limit causal inferences.We also discuss the generalizability of these results to broader populations given the study's focus on the Chinese demogra-phic.By addressing these concerns,we suggest a more nuanced interpretation of the associations between GSD,NAFLD,and KSD,advocating for longitudinal studies to validate these findings and enhance their applicability in global health contexts.

Exploring the links between gallstone disease, non-alcoholic fattyliver disease, and kidney stones: A path to comprehensiveprevention

The recent study exploring the bidirectional associations between gallstone disease,non-alcoholic fatty liver disease,and kidney stone disease highlights a critical concern in chronic disease management.Given the rising global prevalence of these conditions,understanding their interconnections is essential.The study emphasizes the importance of shared risk factors,such as obesity,type 2 diabetes,dyslipidemia,and oxidative stress,and calls for multidisciplinary screening strategies.This approach would improve patient outcomes and reduce the socio-economic burden.While the study contributes valuable insights from a Chinese population,further research across diverse populations is necessary to validate and extend these findings globally.Ultimately,the research underscores the need for integrated prevention programs to better manage these interconnected diseases and improve health outcomes.

Common bile duct stump stones and recurrent acute pancreatitis after Roux-en-Y choledochojejunostomy in a child:A case report

BACKGROUND Pancreaticobiliary maljunction(PBM)is a rare congenital abnormality in pancreaticobiliary duct development.PBM is commonly found in children,and it often leads to acute pancreatitis and other diseases as a result of pancreaticobiliary reflux.Roux-en-Y choledochojejunostomy is a common surgical method for the treatment of PBM,but there are several associated complications that may occur after this operation.CASE SUMMARY The patient,a 12-year-old female,was hospitalized nearly 20 times in 2021 for recurrent acute pancreatitis.In 2022,she was diagnosed with PBM and underwent laparoscopic common bile duct resection and Roux-en-Y choledochojejunostomy in a tertiary hospital.In the first year after surgery,the patient had more than 10 recurrent acute pancreatitis episodes.After undergoing abdominal computed tomography and other examinations,she was diagnosed with“residual bile duct stones and recurrent acute pancreatitis”.On January 30,2024,the patient was admitted to our hospital due to recurrent upper abdominal pain and was cured through endoscopic retrograde cholangiopancreatography.CONCLUSION This article reports a case of a child with distal residual common bile duct stones and recurrent acute pancreatitis after Roux-en-Y choledochojejunostomy for PBM.The patient was cured through endoscopic retrograde cholangiopancreatography.

Endoscopic retrograde cholangiopancreatography,endoscopic papillary balloon dilation,and laparoscopic hepatectomy for intraand extrahepatic bile duct stones

BACKGROUND Intrahepatic and extrahepatic bile duct stones(BDSs)have a high rate of residual stones,a high risk of recurrence,and a high rate of reoperation.It is very important to take timely and effective surgical intervention for patients.AIM To analyze the efficacy,postoperative rehabilitation,and quality of life(QoL)of patients with intra-and extrahepatic BDSs treated with endoscopic retrograde cholangiopancreatography(ERCP)+endoscopic papillary balloon dilation(EPBD)+laparoscopic hepatectomy(LH).METHODS This study selected 114 cases of intra-and extrahepatic BDSs from April 2021 to April 2024,consisting of 55 cases in the control group receiving laparoscopic common bile duct exploration and LH and 59 cases in the observation group treated with ERCP+EPBD+LH.Efficacy,surgical indicators[operation time(OT)and intraoperative blood loss(IBL)],postoperative rehabilitation(time for body temperature to return to normal,time for pain relief,and time for drainage to reduce jaundice),hospital stay,medical expenses,and QoL[Gastrointestinal Quality of Life Index(GIQLI)]were comparatively analyzed.Further,Logistic regression analysis was conducted to analyze factors influencing the QoL of patients with intra-and extrahepatic BDSs.RESULTS The data demonstrated a higher overall effective rate in the observation group compared to the control group(P=0.011),together with notably reduced OT,less IBL,shorter body temperature recovery time,pain relief time,time for drainage to reduce jaundice,and hospital stay(all P<0.05).The postoperative GIQLI of the observation group was more significantly increased compared to the control group(P<0.05).The two groups demonstrated no marked difference in medical expenses(P>0.05).CONCLUSION The above indicates that ERCP+EPBD+LH is effective in treating patients with intra-and extrahepatic BDSs,which is conducive to postoperative rehabilitation and QoL improvement,with promising prospects for clinical promotion.

Clip-stone and T clip-sinus post laparoscopic biliary surgery:Two case reports and review of the literature

BACKGROUND Laparoscopic cholecystectomy(LC)and laparoscopic common bile duct exploration(LCBDE)are widely used in gallbladder and biliary tract diseases.During these procedures,vessels or tissues are commonly ligated using clips.However,postoperative migration of clips to the common bile duct(CBD)or Ttube sinus tract is an overlooked complication of laparoscopic biliary surgery.Previously,most reported cases of postoperative clip migration involved metal clips,with only a few cases involving Hem-o-lok clips and review of the literature.CASE SUMMARY This report describes two cases in which Hem-o-lok clips migrated into the CBD and the T-tube sinus tract following laparoscopic surgery.Case 1 is a 68-year-old female admitted due to abdominal discomfort,and two Hem-o-lok clips were found to have migrated into the CBD 17 months after LC and LCBDE with T-tube drainage,and were removed using a stone extraction balloon.The patient was discharged smoothly after recovery.Case 2 is a 74-year-old male who underwent LC and LCBDE with T-tube drainage and laparoscopic biliary tract basket stone extraction.Nine weeks postoperatively,following T-tube removal,a Hem-o-lok clip was found in the sinus tract,and was extracted from the T-tube sinus tract.The patient recovered smoothly postoperatively.This study also reviews the literature from 2013 to July 2024 on using Hem-o-lok clips in LC and/or LCBDE treatment of gallbladder and biliary diseases and the postoperative migration of these clips into the CBD,T-tube sinus tract,or duodenum.CONCLUSION In patients with a history of LC and/or LCBDE,clip migration should be considered as a differential diagnosis.

Removal of intrahepatic bile duct stone could reduce the risk of cholangiocarcinoma

Hepatolithiasis(HL)poses a significant risk for cholangiocarcinoma(CCA)development,with reported incidences ranging from 5%-13%.Risk factors include older age,smoking,hepatitis B infection,and prolonged HL duration.Chronic inflammation and mechanical stress on the biliary epithelium contribute to CCA pathogenesis.Hepatectomy reduces CCA risk by removing stones and atrophic liver segments.However,residual stones and incomplete removal increase CCA risk.Kim et al identified carbohydrate antigen 19-9,carcinoembryonic antigen,and stone laterality as CCA risk factors,reaffirming the importance of complete stone removal.Nonetheless,challenges remain in preventing CCA recurrence post-surgery.Longer-term studies are needed to elucidate CCA risk factors further.

Removal of intrahepatic bile duct stone could reduce the risk of cholangiocarcinoma: A single-center retrospective study in South Korea

BACKGROUND Intrahepatic duct(IHD)stones are among the most important risk factors for cholangiocarcinoma(CCC).Approximately 10%of patients with IHD stones develop CCC;however,there are limited studies regarding the effect of IHD stone removal on CCC development.AIM To investigate the association between IHD stone removal and CCC development.METHODS We retrospectively analyzed 397 patients with IHD stones at a tertiary referral center between January 2011 and December 2020.RESULTS CCC occurred in 36 of the 397 enrolled patients.In univariate analysis,chronic hepatitis B infection(11.1%vs 3.0%,P=0.03),carbohydrate antigen 19-9(CA19-9,176.00 vs 11.96 II/mL,P=0.010),stone located in left or both lobes(86.1%vs 70.1%,P=0.042),focal atrophy(52.8%vs 26.9%,P=0.001),duct stricture(47.2%vs 24.9%,P=0.004),and removal status of IHD stone(33.3%vs 63.2%,P<0.001)were significantly different between IHD stone patients with and without CCC.In the multivariate analysis,CA19-9>upper normal limit,carcinoembryonic antigen>upper normal limit,stones located in the left or both lobes,focal atrophy,and complete removal of IHD stones without recurrence were independent factors influencing CCC development.However,the type of removal method was not associated with CCC risk.CONCLUSION Complete removal of IHD stones without recurrence could reduce CCC risk.

Extracorporeal shockwave lithotripsy in the management of urinary stones: New concepts and techniques to improve outcomes

Objective: Extracorporeal shockwave lithotripsy (SWL) currently plays an important role in the treatment of urinary tract lithiasis. The purpose of this article was to describe new concepts and procedural strategies that would improve results using SWL as a treatment for urolithiasis, thereby achieving better clinical practice.Methods: A systematic review process was carried in PubMed/PMC from January 2003 to March 2023. A narrative synthesis of the most important aspects has been made.Results: The important recommendations for the adequate selection of the candidate patient for treatment with SWL are summarized, as well as the new strategies for a better application of the technique. Aspects about intraoperative position, stone localization and monitoring, analgesic control, machine and energy settings, and measures aiming at reduced risk of complications are described.Conclusion: To achieve the therapeutic goal of efficient stone disintegration without increasing the risk of complications, it is necessary to make an adequate selection of patients and to pay special attention to several important factors in the application of treatment. Technological development in later generation devices will help to improve current SWL results.

Natural history of asymptomatic gallbladder stones in clinic without beds:A long-term prognosis over 10 years

BACKGROUND Several studies have explored the long-term prognosis of patients with asymp-tomatic gallbladder stones.These reports were primarily conducted in facilities equipped with beds for addressing symptomatic cases.AIM To report the long-term prognosis of patients with asymptomatic gallbladder stones in clinics without bed facilities.METHODS We investigated the prognoses of 237 patients diagnosed with asymptomatic gallbladder stones in clinics without beds between March 2010 and October 2022.When symptoms developed,patients were transferred to hospitals where appropriate treatment was possible.We investigated the asymptomatic and survival periods during the follow-up.RESULTS Among the 237 patients,214(90.3%)remained asymptomatic,with a mean asymptomatic period of 3898.9279±46.871 d(50-4111 d,10.7 years on average).Biliary complications developed in 23 patients(9.7%),with a mean survival period of 4010.0285±31.2788 d(53-4112 d,10.9 years on average).No patient died of biliary complications.CONCLUSION The long-term prognosis of asymptomatic gallbladder stones in clinics without beds was favorable.When the condition became symptomatic,the patients were transferred to hospitals with beds that could address it;thus,no deaths related to biliary complications were reported.This finding suggests that follow-up care in clinics without beds is possible.

Percutaneous antegrade management of large proximal ureteral stones using non-papillary puncture

Objective:To evaluate the feasibility and the safety of medial non-papillary percutaneous nephrolithotomy(npPCNL)for the management of large proximal ureteral stones.Methods:We evaluated prospectively collected data of 37 patients with large proximal ureteral stones more than 1.5 cm in diameter treated by prone npPCNL.Depending on stone size,in-toto stone removal or lithotripsy using the Lithoclast®Trilogy(EMS Medical,Nyon,Switzerland)was performed.Perioperative parameters including operative time(from start of puncture to the skin suturing),stone extraction time(from the first insertion of the nephroscope to the extraction of all stone fragments),and the stone-free rate were evaluated.Results:Twenty-one males and 16 females underwent npPCNL for the management of large upper ureteral calculi.The median age and stone size of treated patients were 58(interquartile range[IQR]:51-69)years and 19.3(IQR:18.0-22.0)mm,respectively.The median operative time and stone extraction time were 25(IQR:21-29)min and 8(IQR:7-10)min,respectively.One case(2.7%)of postoperative bleeding and two cases(5.4%)of prolonged fever were managed conservatively.The stone-free rate at a 1-month follow-up was 94.6%.Conclusion:The npPCNL provides a straight route to the ureteropelvic junction and proximal ureter.Approaching from a dilated portion of the ureter under low irrigation pressure with larger diameter instruments results in effective and safe stone extraction within a few minutes.

Comparative study of thulium fiber laser versus holmium:yttrium-aluminum-garnet laser for ureteric stone management with semi-rigid ureteroscopy: A prospective, single-center study

Objective:To compare the efficacy and safety of thulium fiber laser(TFL)and holmium:yttrium-aluminum-garnet(Ho:YAG)laser for ureteric stone management with semi-rigid ureteroscopy.Methods:In a prospective study from January 2020 to December 2021,we compared 40 patients in each group who underwent semi-rigid ureteroscopic lithotripsy with TFL and that with Ho:YAG laser.Stone volume,stone density,stone fragmentation rates,total lasing time,total operative time,endoscopic vision,retropulsion and stone free rates were analyzed in both groups and compared.Results:Mean stone volume was comparable in the TFL group and the Ho:YAG laser group(282.45[standard deviation,SD 139.79]mm3 vs.279.49[SD 312.52]mm3;p=0.964).Mean stone density was also comparable in the TFL group and the Ho:YAG laser group(1135.30[SD 317.04]Hounsfield unit vs.1131.75[SD 283.03]Hounsfield unit;p=0.959).The mean stone fragmentation rates calculated as stone volume divided by lasing time were 25.85(SD 10.61)mm3/min and 21.37(SD 14.13)mm3/min in the TFL group and the Ho:YAG laser group,respectively(p=0.113).The mean total lasing time(10.15[SD]4.69 min vs.11.43[SD 4.56]min;p=0.222),mean operative time(25.13[SD 9.51]min vs.25.54[SD 10.32]min;p=0.866),and mean total hospital stay(2.62[SD 0.77]days vs.2.61[SD 0.84]days;p=0.893)were comparable in the TFL group and in the Ho:YAG group.The vision was better and retropulsion was less in the TFL group.The stone-free rate at 1 month postoperatively was slightly better in the TFL group(100%vs.90%;p=0.095).

Oxalate regulates crystal-cell adhesion and macrophage metabolism via JPT2/PI3K/AKT signaling to promote the progression of kidney stones

Oxalate is an organic dicarboxylic acid that is a common component of plant foods.The kidneys are essential organs for oxalate excretion,but excessive oxalates may induce kidney stones.Jupiter microtubule associated homolog 2(JPT2)is a critical molecule in Ca^(2+)mobilization,and its intrinsic mechanism in oxalate exposure and kidney stones remains unclear.This study aimed to reveal the mechanism of JPT2 in oxalate exposure and kidney stones.Genetic approaches were used to control JPT2 expression in cells and mice,and the JPT2 mechanism of action was analyzed using transcriptomics and untargeted metabolomics.The results showed that oxalate exposure triggered the upregulation of JPT2,which is involved in nicotinic acid adenine dinucleotide phosphate(NAADP)-mediated Ca^(2+)mobilization.Transcriptomic analysis revealed that cell adhesion and macrophage inflammatory polarization were inhibited by JPT2 knockdown,and these were dominated by phosphatidylinositol 3-kinase(PI3K)/AKT signaling,respectively.Untargeted metabolomics indicated that JPT2 knockdown inhibited the production of succinic acid semialdehyde(SSA)in macrophages.Furthermore,JPT2 deficiency in mice inhibited kidney stones mineralization.In conclusion,this study demonstrates that oxalate exposure facilitates kidney stones by promoting crystal-cell adhesion,and modulating macrophage metabolism and inflammatory polarization via JPT2/PI3K/AKT signaling.

Cost-Effectiveness Analysis of Renalof® versus Extracorporeal Shockwave Lithotripsy (ESWL) for the Treatment of Kidney Stones ≤ 1 cm in Nicaragua

Objectives: To assess the efficiency in terms of cost-effectiveness (CE) of oral Renalof® treatment versus extracorporeal shockwave lithotripsy (ESWL) in the treatment of kidney stones ≤ 1 cm in Nicaragua. Methods: A cost-effectiveness economic evaluation was carried out based on the results obtained in the randomised, prospective, observational, single-blind, prospective, phase 2 clinical trial. Cost-effectiveness and the incremental cost-effectiveness ratio (ICER) were calculated. Economic data were obtained from the Economics Department of Clínica Senior in Managua, Nicaragua. The monetary cost was expressed in US dollars (USD). Results: Treatment with Renalof® yielded a CE of $1,323.08/% remission, while ESWL was $9,498.54/% remission. The ICER shows that, in order to achieve a high percentage of kidney stone remission with ESWL, an extra $4,734.70 per patient must be invested. Conclusions: The use of Renalof® is shown to be a more cost-effective option than ESWL. It is recommended for the treatment of kidney stones ≤ 1 cm in size.

Laparoscopic cholecystectomy plus common bile duct exploration for extrahepatic bile duct stones and postoperative recurrenceassociated risk factors

BACKGROUND There remain controversies regarding the surgical treatment of extrahepatic bile duct stones(EHBDSs)in clinical practice.AIM To explore the curative effect of laparoscopic cholecystectomy(LC)plus common bile duct exploration(CBDE)for the surgical treatment of EHBDSs and to analyze the risk factors that affect postoperative stone recurrence.METHODS Eighty-two patients with EHBDSs admitted between March 2017 and March 2023 were selected.Among them,patients treated with open choledocholithotomy plus LC or open cholecystectomy(OC)were set as the control group(n=40),and those treated with LC plus CBDE served as the observation group(n=42).The surgical outcomes of the two groups were compared,the surgical complications and Gas-trointestinal Quality of Life Index(GIQLI)scores were counted,and the one-year prognostic recurrence was recorded.Independent factors for postoperative re-currence were determined using univariate and multivariate analyses.RESULTS The two groups were comparable in the stone residual rate(P>0.05).The ope-ration time(P<0.05),intraoperative bleeding(P<0.05),and total complication rate(P=0.005)were lower in the observation group than in the control group.The observation group exhibited a marked increase in the GIQLI score,which was higher than the control group(P<0.05).A lower one-year recurrence rate was determined in the observation group vs the control group(P=0.027).Sphincter of Oddi dysfunction[odds ratio(OR)=5.712,P=0.007]and the treatment scheme of open choledocholithotomy plus LC or OC(OR=6.771,P=0.008)were the independent risk factors for one-year recurrence in patients after surgery.CONCLUSION LC plus CBDE for patients with EHBDSs can reduce stone residuals,intraoperative bleeding,complications,and postoperative recurrence.

Clinical efficacy of laparoscopic cholecystectomy combined with endoscopic papillary balloon dilation in treatment of gallbladder stones with common bile duct stones: A retrospective study

BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic papillary balloon dilation(EPBD)in patients with gallbladder stones(GS)with common bile duct stones(CBDS).METHODS The clinical data of 102 patients with GS combined with CBDS were selected for retrospective analysis and divided into either an LC+EPBD group(n=50)or an LC+endoscopic sphincterotomy(EST)group(n=52)according to surgical methods.Surgery-related indexes,postoperative recovery,postoperative complications,and expression levels of inflammatory response indexes were compared between the two groups.RESULTS Total surgical time,stone free rate,rate of conversion to laparotomy,and successful stone extraction rate did not differ significantly between the LC+EPBD group and LC+EST group.Intraoperative hemorrhage,time to ambulation,and length of hospitalization in the LC+EPBD group were lower than those of the LC+EST group(P<0.05).The rate of total complications of the two groups was 9.80%and 17.65%,respectively,and the difference was not statistically significant.No serious complications occurred in either group.At 48 h postoperatively,the expression levels of interleukin-6,tumor necrosis factor-α,high-sensitivity Creactive protein,and procalcitonin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).At 3 d postoperatively,the expression levels of aspartate transaminase,alanine transaminase,and total bilirubin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).CONCLUSION LC combined with EPBD and LC combined with EST are both effective procedures for the treatment of GS with CBDS,in which LC combined with EPBD is beneficial to shorten the patient’s hospitalization time,reduce the magnitude of elevated inflammatory response indexes,and promote postoperative recovery.

Is fluoroscopy-free single-use flexible ureteroscopy a feasible treatment for kidney stones with abnormal renal anatomy?

Objective:This study aimed to evaluate the feasibility of the fluoroscopy-free single-use flexible ureteroscopy procedure in the treatment of kidney stones with abnormal renal anatomy compared to normal renal anatomy.Methods:Forty patients with abnormal (Group A) and 80 patients with normal (Group B) renal anatomy who had 10–20 mm renal stones were included. They were treated with LithoVue single-use flexible ureteroscopy (Boston Scientific, Marlborough, MA, USA) after ureteric dilatation by two different size semi-rigid ureteroscopes. This technique was chosen as the aim was to exclude any ureteric pathology (e.g., stone or stricture), confirm the placement of a safe guidewire, avoid balloon dilatation of the ureter, and achieve safe insertion of a 12 Fr, 35/45 cm ureteric access sheath with optical and tactile sign and without fluoroscopy image for guidance.Results:The mean ages were 43 years and 45 years in Group A and Group B, respectively. The mean stone burden was 14.62 (standard deviation: 5.35) mm^(3) and 14.79 (standard deviation: 4.58) mm^(3) in Group A and Group B, respectively. There is no significant difference between both groups according to the mean operative time, hospital stay, or stone-free rate. The stone-free rate was about 93% in both groups when the stone size was between 10 mm and 15 mm, and less than 54% when the stone size was more than 15 mm to 20 mm. In the majority of cases (80.0% in Group A and 92.5% in Group B), we completed the procedure without fluoroscopy. The perioperative complication rates were comparable in the two groups.Conclusion:Fluoroscopy-free single-use flexible ureteroscopy, when performed by expert urologists, is a feasible treatment for pre-stented patients with kidney calculi of ≤15 mm with abnormal renal anatomy.

Bioleaching of vanadium from stone coal vanadium ore by Bacillus mucilaginosus:Influencing factors and mechanism

Vanadium and its derivatives are used in various industries,including steel,metallurgy,pharmaceuticals,and aerospace engineering.Although China has massive reserves of stone coal resources,these resources have low grades.Therefore,the effective extraction and recovery of metallic vanadium from stone coal is an important way to realize the efficient resource utilization of stone coal vanadium ore.Herein,Bacillus mucilaginosus was selected as the leaching strain.The vanadium leaching rate reached 35.5%after 20 d of bioleaching under optimal operating conditions.The cumulative vanadium leaching rate in the contact group reached 35.5%,which was higher than that in the noncontact group(9.3%).The metabolites of B.mucilaginosus,such as oxalic,tartaric,citric,and malic acids,dominated in bioleaching,accounting for 73.8%of the vanadium leaching rate.Interestingly,during leaching,the presence of stone coal stimulated the expression of carbonic anhydrase in bacterial cells,and enzyme activity increased by 1.335-1.905 U.Enzyme activity positively promoted the production of metabolite organic acids,and total organic acid content increased by 39.31 mg·L^(-1),resulting in a reduction of 2.51 in the pH of the leaching system with stone coal.This effect favored the leaching of vanadium from stone coal.Atomic force microscopy illustrated that bacterial leaching exacerbated corrosion on the surface of stone coal beyond 10 nm.Our study provides a clear and promising strategy for exploring the bioleaching mechanism from the perspective of microbial enzyme activity and metabolites.