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Objective To investigate the preparation of a polycaprolactone (PCL)/poly (lactic acid-glycolic acid) (PLGA) degradable ureteral stent and its degradation ability in vitro.Methods From December 2010 to September 2012,degradable ureteral stent was fabricated by electrospinning,using different concentration of PCL/PLGA (5％,10％,15％,20％,25％,30％).The structure of stent was scanned by electron microscopy (SEM).The Instron system was used to test the mechanical property of those stents.The PCL/PLGA stents of different concentration (5％,15％,25％) were immerged into the urine to assess their degradable ability 7,14,21,28,35,42,49,56 days later.Results The inner diameter of the white tubular scaffold was 1.5 mm and the outer diameter was 2.0 mm.The SEM results showed that the scaffold had been made by nanofiber with the structure of multi-porous.The tension test showed that the mechanical property was enhanced with the increasing in the proportion of the PCL.The lowest stress at break was found in 5％ PCL/PLGA stent,while it was still sufficient for the mechanical criteria of degradable biomaterial.The degradation curves of different ratio of PCL/PLGA stent were close to a straight line.The 5％ PCL/PLGA stent collapsed into pieces within 28 d.The 15％ and 25％ PCL/PLGA collapsed within 42 d and 56 d,respectively.Conclusion The PCL/PLGA biodegradable ureteral stent has a good mechanical property and the degradation time can fully meet the demand of a ureteral stent.
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Objective The present study was designed to investigate the risk factors affecting bleeding during percutaneous nephrolithotomy. Methods The records of 218 patients with percutaneous nephrolithotomy procedure by a single surgeon were retrospectively reviewed.The mean age was 48 years ( range,19 -70).One hundred and forty six patients had staghore stones,and 7 patients had previous open or percutaneous nephrolithotomy histories.Forty-one patients had concomitant diabetes mellitus,and 89 cases had hypertension.The following factors including age,sex,BMI,diabetes status,hypertension status,stone type,calix of puncture,previous open or percutaneous nephrolithotomy history,number of accesses,size of accesses,operative time,and surgeon experience were analyzed.Univariate analysis and multivariate step regression analysis were used for statistical assessment. Results 207 procedures were successfully performed,and 11 patients failed because of difficulty to establish the accesses.Single-tract was used in 176 cases and multiple-tract was used in 31 cases.163 cases were performed via a 18 F access and 44 cases via a 24 F access.The mean operative time was 78.4 min.The overall blood transfusion rate was 7.7％,and stone type ( P =0.034),diabetes ( P =0.030),number of accesses ( P =0.019 ),size of accesses ( P =0.008) and operative time (P =0.001 ) were the risk factors affecting blood transfusion requirement.The average hemoglobin (Hb) drop after percutaneous nephrolithotomy procedures was 11.2 g/L,and stone type ( P ＜ 0.001 ),diabetes ( P =0.015 ),number of accesses ( P =0.016),size of accesses ( P ＜ 0.001 ) and operative time ( P ＜ 0.001 ) were the risk factors affecting Hb drop.The following covariates including Hb drop:age,sex,BMI,previous open or percutaneous nephrolithotomy history,hypertension status,calix of puncture and surgeon experience were not risk factors affecting blood transfusion requirement and Hb drop.Multivariate stepwise regression analysis showed that diabetes ( OR =1.75 ),stone type ( OR =1.92),number of accesses ( OR =2.45 ),size of accesses ( OR =1.32) and operative time ( OR =1.66) significantly increased risk of bleeding. Conclusions Stone type,diabetes,number of accesses,size of accesses and operative time were the risk factors affecting blood loss during percutaneous nephrolithotomy.
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Objective To study the expression of enhancer of zeste homolog 2 (EZH2) gene in transitional cell carcinoma (TCC) of the bladder celt lines, carcinoma tissues and normal bladder tis-sues and to evaluate the roles of EZH2 in the development and progression of bladder carcinoma. Methods RT-PCR, Western-blot and immunocytochemistry were used to analyze the expression of EZH2 of the bladder cell lines (T24, EJ, MGH-U1, BIU-87). The prostate cancer cell line PC-3M was used as an EZH2-positive cell line. EZH2 gene expressions in 45 cases of bladder carcinoma and 12 cases of normal bladder mueosa were detected by RT-PCR. Of cancer cases, 31 were superficial tumors and 14 were invasive tumors; 13 were G1, 21 were G2 and 11 were G3. Results EZH2 was detected in the 4 TCC cell lines. The EZH2 expression rate of TCC (82.2%) was significantly higher than that of normal bladder tissues (8.3%, P<0.05). The expression rate in superficial tumors was 74.2% and in invasive tumors was 100.0%, but there was no significant difference (P>0.05). The expression rates increased with tumor cell grade increase, but there was no significant difference (P> 0.05). Conclusions EZH2 could play an important role in the development and progression of blad-der carcinoma. It could be used as a potential gene therapy target of bladder cancer.
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0.05) . In the later stage (8～12 weeks), the tissue reaction nearly subsided in PLGA stented ureters after degradation of the device. Whereas, the tissue reaction induced by UROVISION stent had lasted throughout the observation period, even deteriorated with time going(P