Weimin Yu

Minimally Invasive Tract in Percutaneous Nephrolithotomy for Renal Stones

AIM The aim of this study was to assess the efficacy, safety, and morbidity of minimally invasive tract in percutaneous nephrolithotomy (Mini-PCNL) for renal stones in comparison with the standard PCNL. PATIENTS AND METHODS In a randomized trial, 69 patients (72 renal units) undergoing Mini-PCNL (group 1) from May 2004 to December 2007 were compared with a similar group of 111 (115 renal units) patients undergoing standard PCNL (group 2). Patients who needed more than one percutaneous tract or who had simultaneously undergone the two techniques on the same renal unit were excluded from the study group. Chi-square test was performed for statistical analysis of qualitative variables, and Students t-test for quantitative variables. A p-value of <0.05 was considered significant. RESULTS The two groups had comparable demographic data and some outcome of characteristics such as time of stay in hospital, postoperative pain, dose of postoperative analgesics, ratio of positive fever, and stone-free rates for some types of stones (e.g., staghorn stone and simple renal pelvis stone). The stone-free rate for multiple caliceal stones (85.2% vs. 70.0% in group 1 and group 2) was significantly higher in the Mini-PCNL group (p < 0.05). The incidence of bleeding necessitating transfusion (1.4% vs. 10.4% in group 1 and group 2) was significantly lower in the Mini-PCNL group (p < 0.05). In group 1, operative time for different stone types such as staghorn stone, simple renal pelvis stone, and multiple caliceal stones were 134.3 ± 19.7, 89.4 ± 21.5, and 113.9 ± 20.3 minutes, respectively, which were significantly longer than that for group 2 (118.9 ± 21.5, 77.0 ± 17.6, and 101.2 ± 19.1 minutes) (p < 0.05). CONCLUSION Mini-PCNL is safe and effective for managing renal calculi in adult patients. Although smaller working sheath is associated with longer operative time, Mini-PCNL has significantly lower incidence of bleeding necessitating transfusion and higher stone-free rate for multiple caliceal stones in comparison with the standard PCNL.

p130Cas, E-cadherin and β-catenin in human transitional cell carcinoma of the bladder: Expression and clinicopathological significance

Objectives:  To investigate the effects of junction protein, p130 Crk‐associated substance (p130Cas), and adhesion molecules, E‐cadherin and β‐catenin, on the biological behavior of transitional cell carcinoma of the bladder.

Retrograde ureteroscopic treatment for upper ureteral stones: a 5-year retrospective study.

PURPOSE To review our 5-year experience with retrograde ureteroscopic treatment for patients with upper ureteral stones and to compare the outcome, safety, and efficiency of pneumatic and holmium laser lithotripsy in managing upper ureteral stones. PATIENTS AND METHODS We retrospectively analyzed the hospital records of 372 patients who underwent 384 retrograde ureteroscopic procedures for upper ureteral stones at our center from January 2003 to December 2007. Patient and stone characteristics, treatment variables. and clinical outcomes were assessed. Factors such as failure of the procedure, stone clearance, intraoperative and postoperative morbidity, procedure duration, and hospital stay were analyzed and compared between pneumatic (group 1) and laser lithotripsy (group 2). RESULTS Overall, the stone-free rate was 90.4%, the mean operative duration was 41.2 ± 10.7 minutes, the mean postoperative hospital stay was 2.7 ± 0.9 days, and the rates of intraoperative and postoperative complications were 14.6% and 3.9%, respectively, for groups 1 and 2. In comparing group 1 and group 2, the significantly higher number of intraoperative complications coincide with a significantly lower stone-free rate. Nevertheless, the incidence of intraoperative and postoperative complications between the two groups was not statistically significant except in the case of stone upward migration. The mean operative time of group 2 was 43.3 ± 11.1 minutes, which was significantly longer than that for group 1, which was 38.7 ± 9.1 minutes (P < 0.05). CONCLUSION Retrograde ureteroscopy is a safe and effective method for managing upper ureteral stones. A high postoperative stone-free rate is associated with the refined use of a holmium laser lithotriptor to ensure thoroughness while avoiding migration of the stones into the renal pelvis. Although laser lithotripsy has a longer operative time, it remains the more appropriate choice for managing upper ureteral stones.

Detection of Prostate Stem Cell Antigen Expression in Human Prostate Cancer Using Quantum-Dot-Based Technology

Quantum dots (QDs) are a new class of fluorescent labeling for biological and biomedical applications. In this study, we detected prostate stem cell antigen (PSCA) expression correlated with tumor grade and stage in human prostate cancer by QDs-based immunolabeling and conventional immunohistochemistry (IHC), and evaluated the sensitivity and stability of QDs-based immunolabeling in comparison with IHC. Our data revealed that increasing levels of PSCA expression accompanied advanced tumor grade (QDs labeling, r = 0.732, p < 0.001; IHC, r = 0.683, p < 0.001) and stage (QDs labeling, r = 0.514, p = 0.001; IHC, r = 0.432, p = 0.005), and the similar tendency was detected by the two methods. In addition, by comparison between the two methods, QDs labeling was consistent with IHC in detecting the expression of PSCA in human prostate tissue correlated with different pathological types (K = 0.845, p < 0.001). During the observation time, QDs exhibited superior stability. The intensity of QDs fluorescence remained stable for two weeks (p = 0.083) after conjugation to the PSCA protein, and nearly 93% of positive expression with their fluorescence still could be seen after four weeks.

Acute kidney injury induced by various pneumoperitoneum pressures in a rabbit model of mild and severe hydronephrosis.

Objective: Increased pneumoperitoneum pressure during laparoscopic surgery can result in acute kidney injury. We aimed to clarify whether intraabdominal pressure tolerance is modified in various degrees of unilateral kidney hydronephrosis in rabbits. Methods: A total 90 rabbits were randomly allocated to three groups (group PN, PM and PS, i.e. rabbits with no, mild and severe hydronephrosis, respectively, subjected to intraabdominal pressures). Rabbits in group PM (n = 30) and group PS (n = 30) underwent a surgical procedure inducing a mild or severe left hydronephrosis. Rabbits in all groups were then allocated to 5 subgroups. Then, they were subjected to intraabdominal pressures of 0, 6, 9, 12, and 15 mm Hg, respectively. Acute kidney injury was assessed by measuring serum creatinine (Scr), blood urea nitrogen (BUN), tubular cell apoptosis, kidney injury molecule-1 (KIM-1) and cysteine-rich 61 (Cyr-61/CCN1) expression. Results: Acute kidney injury with increased tubular apoptosis and KIM-1 and Cyr-61 expression occurred when intraabdominal pressure reached 15, 15 and 9 mm Hg in PN, PM and PS groups, respectively. The Scr and BUN levels were similar in all groups. Conclusions: In rabbits, kidneys with severe hydronephrosis were more likely to suffer acute injury when they were exposed to pneumoperitoneal pressure.

Quantum-dot-based technology for sensitive and stable detection of prostate stem cell antigen expression in human transitional cell carcinoma.

Quantum dots (QDs) as a biological labeling material for medical applications need to be evaluated for the sensitivity and stability of their fluorescence. Comparison of QD-based immunolabeling and commonly used immunohistochemical staining in detecting the expression of prostate stem cell antigen (PSCA) in bladder tumor tissues revealed that the two methods had similar sensitivity in the differential display of PSCA expression correlated with tumor stage and grade (kappa=0.92, p<0.001). In addition, the intensity of QD fluorescence remained stable for at least 10 days after conjugation to the PSCA protein and nearly 96% of the positive expression in samples lasted for one month.

Laparoscopic Varicocelectomy in Adolescents: Artery Ligation and Artery Preservation

OBJECTIVE To evaluate and compare the perioperative outcomes and improvements of testicular performance between artery preservation (AP) and artery ligation (AL) during laparoscopic varicocelectomy (LV) in adolescents. MATERIALS AND METHODS Data on 122 adolescents with unilateral varicocele who underwent laparoscopic varicocelectomy by a single urologist at our hospital were retrospectively studied. Age, varicocele grade, and testicular volume were collected, and postoperative data, including the operative time, recurrence, hydrocele, and catch-up growth, were assessed. Pre- and postoperative semen parameters in partial patients were compared between the groups. RESULTS The preoperative data were comparable between the groups, and there were no significant intergroup differences in the postoperative recurrence rate, hydrocele rate, or the 12th- and 24th-month catch-up growth rates; however, the 12th-month catch-up growth rate was relatively low in the AL group compared with the AP group. The postoperative semen parameters in terms of concentration, motility, and morphology were (62.5 ± 39.2) million/ml, (52.2 ± 16.6)%, and (11.5 ± 1.5)% in AP group, and (60.4 ± 38.2) million/ml, (49.1 ± 19.9)%, and (10.7 ± 1.5)% in AL group, respectively. The semen parameters were improved in both groups (P < .05) when compared with preoperative data, and there was no statistically significant difference between the two procedures (P > .05). CONCLUSIONS Considering the short-term impact on testicular restoration of the AL procedure, we suggest the AP procedure with fast and gentle dissection of the artery as the first choice. We also suggest a timely conversion to the AL procedure without hesitation when the first attempt fails.

Oxidative Damage and Mitochondrial Injuries Are Induced by Various Irrigation Pressures in Rabbit Models of Mild and Severe Hydronephrosis.

Objective We aimed to study whether tolerance to irrigation pressure could be modified by evaluating the oxidative damage of obstructed kidneys based on rabbit models experiencing different degrees of hydronephrosis. Methods A total of 66 rabbits were randomly divided into two experimental groups and a control group. In the experimental groups, the rabbits underwent a surgical procedure inducing mild (group M, n=24) or severe (group S, n=24) hydronephrosis. In each experimental group, the rabbits were then randomly divided into 4 subgroups (M0-M3 and S0-S3) consisting of 6 rabbits each. Group 0 received no perfusion. Groups 1 through 3 were perfused with 20, 60 and 100 mmHg fluid, respectively. For the control group, after a sham operation was performed, the rabbits were divided into 4 subgroups and were perfused with fluid at 0, 20, 60 or 100 mmHg of pressure. Kidney injuries was evaluated by neutrophil gelatinase associated lipocalin (NGAL). Oxidative damage was assessed by analyzing superoxide dismutase (Mn-SOD) activity, malondialdehyde (MDA) levels, glutathione reductase (GR), catalase (CAT) and peroxide (H2O2) levels, mitochondrial injuries was assessed by mitochondrial membrane potential (MMP), the mitochondrial ultrastructure and tubular cell apoptosis. Results In the experimental groups, all results were similar for groups 0 and 1. In group 2, abnormalities were observed in the S group only, and the kidneys of rabbits in group 3 suffered oxidative damage and mitochondrial injuries with increased NGAL, decreased Mn-SOD, GR and CAT,increased MDA and H2O2, lower levels of MMP, mitochondrial vacuolization and an increased apoptotic index. Conclusion In rabbits, severely obstructed kidneys were more susceptible to oxidative damage and mitochondrial injury than mildly obstructed kidneys when subjected to higher degrees of kidney perfusion pressure.

Acute Kidney Injuries Induced by Various Irrigation Pressures in Rat Models of Mild and Severe Hydronephrosis

OBJECTIVE To clarify whether tolerance to irrigation pressure could be modified over varying degrees of kidney obstruction during the endoscopic treatment of kidney stones in a rat model. METHODS A total of 126 rats were randomly allocated into 2 experimental groups and a control group. The experimental groups underwent a surgical procedure to induce mild (group M, n = 60) or severe (group S, n = 60) hydronephrosis. In each group, the rats were then randomly allocated into 4 subgroups (M0 to M3 and S0 to S3) of respectively 6, 18, 18, and 18 rats. Groups 0 to 3 were respectively perfused with 0 (no irrigation), 20, 60, and 100 mm Hg pressure fluid. The control group underwent no surgical procedures and was only perfused with 100 mm Hg pressure fluid. Acute kidney injuries were assessed by analyzing the kidney microstructure, tubular cell apoptosis, kidney injury molecule-1, and cysteine-rich 61 (Cyr61/CCN1) expression using immunohistochemistry. RESULTS No abnormalities were observed for the control group, groups 0, or 1. In group 2, abnormalities were observed only in the S group, whereas all kidneys in group 3 suffered acute kidneys injuries, along with occurrence of tubular cells necrosis, increased apoptosis, and increased expression of kidney injury molecule-1 and Cyr61. CONCLUSION Rats with severely obstructed kidneys were more likely to suffer acute kidney injuries than those with less obstructed kidneys when exposed to higher kidney irrigation pressures. This suggests that the pressure should be controlled and reduced when performing endourologic procedures in the context of kidney obstruction.

MALAT1 Promotes Cell Apoptosis and Suppresses Cell Proliferation in Testicular Ischemia-Reperfusion Injury by Sponging MiR-214 to Modulate TRPV4 Expression.

Background/Aims: Accumulating evidences has indicated that aberrant expression of long non-coding RNAs (lncRNAs) is tightly associated with the progression of ischemia-reperfusion injury (IRI). Previous studies have reported that lncRNA MALAT1 regulates cell apoptosis and proliferation in myocardial and cerebral IRI. However, the underlying mechanism of MALAT1 in testicular IRI has not been elucidated. Methods: The levels of MALAT1, some related proteins and apoptosis in the testicular tissues were determined by quantitative real-time PCR, HE staining, immunohistochemistry, western blot and TUNEL assays. Relative expression of MALAT1, miR-214 and related proteins in cells were measured by western blot and quantitative real-time PCR. Cell viability and apoptosis were examined using MTT assay and flow cytometry. Results: In the present study, we found that MALAT1 was up-regulated in animal samples and GC-1 cells. The expression level of MALAT1 was positively related to cell apoptosis and negatively correlated with cell proliferation as testicular IRI progressed. In gain and loss of function assays, we confirmed that MALAT1 promotes cell apoptosis and suppresses cell proliferation in vitro and in vivo. Furthermore, we found that MALAT1 negatively regulates expression of miR-214 and promotes TRPV4 expression at the post-transcriptional level. Consequently, we investigated the correlation between MALAT1 and miR-214 and identified miR-214 as a direct target of MALAT1. In addition, we found that TRPV4 acted as a target of miR-214. Over-expression of miR-214 efficiently abrogated the up-regulation of TRPV4 induced by MALAT1, suggesting that MALAT1 positively regulates the expression of TRPV4 by sponging miR-214. Conclusion: In sum, our study indicated that the lncRNA MALAT1 promotes cell apoptosis and suppresses cell proliferation in testicular IRI via miR-214 and TRPV4.