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【Objective】 To investigate the clinical characteristics and prognostic factors of small cell carcinoma of bladder (SCCB), and to explore the efficacy of neoadjuvant therapy. 【Methods】 Clinical information of 47 SCCB patients were retrospectively collected, and the clinical and pathological features were compared with those of urothelial carcinoma (UBC). The prognostic factors and efficacy of neoadjuvant therapy were also investigated. 【Results】 SCCB had higher baseline tumor staging, and was more likely to invade the muscle (100%) and metastasize distantly (21.3%). The overall survival was poor (median: 13.1 months, 1-year survival rate: 53.7%, 5-year overall survival rate: 15.4%). Tumor T staging was a risk factor for SCCB, while neoadjuvant therapy was an independent protective factor that significantly reduced the risk of recurrence and metastasis (HR: 0.189, 95%CI: 0.051-0.697, P=0.012) and death (HR: 0.177, 95%CI: 0.045-0.698, P=0.013), and significantly improved disease-free survival and overall survival. In addition, compared with neoadjuvant chemotherapy alone, neoadjuvant chemotherapy combined with immunotherapy could improve the pathological complete response rate. 【Conclusion】 SCCB is highly malignant and prone to metastasis, and has a poor prognosis. Neoadjuvant therapy combined with radical cystectomy is recommended as the first-line treatment.
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Objective:To investigate the diagnosis, treatment and prognosis of squamous cell carcinoma of renal pelvis.Methods:The clinic data of 28 cases with squamous cell carcinoma of renal pelvis confirmed by pathologic examination treated during June 2007 and September 2019 was retrospectively analyzed. There were 19 male and 9 female patients, with a median age of 56 years. Hematuria was present in 18 cases, flank pain was present in 11 cases, and abdominal mass was present in 1 case. All 28 cases accepted CT or MRI examination. Renal pelvis or renal tumors were found in 26 cases, and severe hydronephrosis was observed in 2 cases. 2 cases underwent PET/CT, and bone metastasis was found in 1 case. Preoperative diagnoses were renal pelvic tumor in 13 cases, renal tumor in 13 cases and renal abscess in 2 cases. Coexisting renal calculi or renal pelvic calculus was detected in 19 cases. All 28 cases underwent surgical excision, including radical nephroureterectomy in 13 cases, radical nephrectomy in 12 cases, palliative resection in 1 case, and pyonephrenectomy in 2 cases. Enlarged lymph nodes were found in 9 cases during the surgery, and local lymph node dissection was performed in these cases.Results:The mean diameter of the tumors was 8.5 cm. Histopathological examination revealed that 9 cases were well differentiated, 11 cases were moderately differentiated, and 8 case was poorly differentiated. 1 case had pT 2 stage, 15 cases had pT 3 stage and 12 cases had pT 4 stage. 9 cases had lymph node metastasis. 5 cases had renal vein thrombosis. Immunohistochemistry staining exhibited consistent characteristics including CK5(+ ), 34βE12(+ ), p63(+ ), CK20(-) and GATA3(-). Postoperatively, 12 cases received adjuvant therapy including chemotherapy, radiotherapy and/or immunotherapy. Within a median follow-up of 6.0 months (ranging 1-80 months), median overall survival was 10.0 months. 15 cases died of tumor progression. Conclusion:Squamous cell carcinoma is a rare and highly aggressive neoplasm, typically associated with long-lasting renal calculi, hydronephrosis and chronic inflammation. The diagnosis should be established on pathologic examination.CK5, 34βE12 and p63 positivity contribute to the diagnosis of squamous cell carcinoma. Surgery is the foremost choice of treatment, but the risk of recurrence and metastasis is high. The prognosis is extremely poor as the majority of patients are diagnosed with advanced stages.
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Objective:To study the pathological characteristics, diagnosis and treatment of primary adenocarcinoma of renal pelvis and ureter.Methods:The clinical pathological characteristics, treatment and prognosis of 5 patients with adenocarcinoma of upper urinary tract treated between January 2007 and May 2019 was retrospectively reviewed. There were 4 male and 1 female patients, with a median age of 60 years. The major symptoms were hematuria in 5 cases and low back pain in 4 cases. All cases underwent B-ultrasound and CT examination, and 4 cases accepted cystoscopy. Preoperative diagnoses were ureter tumor in 2 cases, renal pelvis tumor in 1 case, renal tumor in 1 case and renal calculus in 1 case.Results:5 cases were treated with surgery. Radical nephroureterectomy was performed in 3 cases, and nephrectomy in one case. 1 case underwent first-stage percutaneous nephrolithotomy and second-stage radical nephroureterectomy due to the discovery of tumor. 1 case was treated with radiotherapy and immune checkpoint inhibitor postoperatively. The mean diameter of the tumors was 4.4 cm. There were 3 renal pelvis adenocarcinomas and 2 ureter adenocarcinomas confirmed by pathologic examination, including 3 cases of pT 3 stage and 1 case of pT 4 stage. Lymph node metastasis was found in 2 cases. Immunohistochemistry revealed that CDX2(+ ), p63(-), GATA3(-), β-catenin(-)were the common features of five cases. The median survival was 12 months with a median follow-up of 6 months. 2 cases died of tumor progression within 1 year. Conclusions:Adenocarcinoma is an extremely rare malignancy, typically associated with long-standing calculi and chronic inflammation. Given the fact that clinical and imaging findings are nonspecific, the diagnosis is based on pathologic examination, supported by glandular structure of histology. Immunohistochemical staining exhibited CDX2 and CK20 positivity and β-catenin negativity, moreover, GATA3, p63 and CK7 was usually negative or partially positive. Surgery is the foremost choice of treatment. The prognosis is correlated with subtypes, whereas the overall prognosis is poor due to high rates of recurrence and metastasis.
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Objective To investigate the prognostic significance of the lymphovascular invasion (LVI) in patients with upper tract urothelial carcinoma (UTUC) after radical nephmureterectomy (RNU).Methods A retrospective review was performed on 812 patients who underwent radical nephroureterectomy for UTUC in our hospital from January 1998 to March 2016.Among all the patients,534 were male and 278 female,with median age 67 years old (ranged 25 to 89 years).Three hundred and three patients had hypertension and 119 patients had diabetes.Hydronephrosis was present in 393 patients.445 patients had tumor in left side and the remaining 367 in right side.The tumor was located in the renal pelvis in 422 patients and was ureteric in 319 patients and multifocal in 71 patients.Low pathological grade and high pathological grade was diagnosed in 239 and 573,respectively.The x2 test was used to detect the association between lymphovascular invasion (LVI) and several clinicopathological features.Kaplan-Meier method with the log-rank test was used to assess overall survival (OS) and cancer-specific survival (CSS).Multivariate analysis was conducted using Cox proportional-hazards regression model.Results There were 396 cases with pathological stage Tis +Ta +T1,135 cases T2,257 cases T3 and 24 cases T4.Of all patients,52 had lymph node metastasis.The median follow-up time was 41 months (ranged 2 to 206 months).Of all 812 patients included,110 patients (13.5%) had LVI,while 702 patients (86.5%) were LV1 negative.The 5-year OS and CSS was 44.8% and 48.9% for LVI positive group while 70.1% and 76.0% for LVI negative group (P < 0.001).Furthermore,there were statistically significant differences between LVI positive group and LVI negative group in hydronephrosis,tumor grade,tumor stage,muscle invasion and lymph node metastasis (P<0.05).Cox regression showed LVI,advanced age (≥65 year),higher tumor grade,advanced tumor stage (≥ pT2),lymph node metastasis and multifocal tumor were significant prognostic factors in patients with UTUC after RUN.Conclusion UTUC may have a poor prognosis and LVI could be an independent predictor of both OS and CSS.
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Objective To discuss the necessity of closing the peritoneum during the operation of ileal conduit after the radical cystectomy.Methods We retrospectively analyzed the clinical data of 395 patients with bladder cancer who received radical cystectomy from Jan.2014 to Sep.2016.The amount of male was 327,female was 68.The mean age was (65.8 ± 9.7) years old.Patients were divided into four groups according to the surgical method of cystectomy and urinary diversion.In group A,patients,including 78 males and 9 females,were received open radical cysectomy (ORC) with extraperitoneal ileal conduit.The mean age was (67.8 ± 9.2) years old.In the preoperative clinical staging,66 cases were less than T2 and 21 cases were more than T2.Preoperative pathological grade in 83 cases and low grade in 4 cases.In group B,patients,including 31 males and 2 females,were accepted ORC with ileal conduit without peritoneum closure.The mean age was (67.3 ± 8.7) years old.Preoperative clinical staging showed less than T2 in 25 cases,more than T2 in 8 cases,The preoperative pathological grade showed high grade in 33 cases.In group C,patients,including 112 males and 27 females,were accpeted LRC with ileal conduit without peritoneum closure.The mean age was (64.3 ± 10.5)years old.The preoperative clinical staging showed less than T2 in 107 cases and more than T2 in 32 cases.The preoperative pathological grade showed high grade in 135 cases and low grade in 4 cases.In group D,patients,including 106 males and 30 females,were accepted RARC with ileal conduit without peritoneum closure.The mean age was (65.9 ±10.0)years old.Preoperative clinical staging showed less than T2 in 103 cases and more than T2 in 33 cases.The preoperative pathological grade showed high grade in 132 cases and low grade in 4 cases.Ileal conduit without peritoneum closure means completely open the peritoneum after anastomosis of the ureter and intestine in the urinary diversion surgery without shutting down the peritoneum,which is different from the extraperitoneal ileal conduit.The operating time,blood loss,blood transfusion rate,recovery time of intestinal function and perioperative complications and rate of hydronephrosis were analyzed.Results The 395 cases completed operation successfully,no LRC or RARC had been converted to ORC.The operative time was (280.1 ± 92.3) min,(233.6 ± 99.4) min,(304.8 ± 108.9) min,(364.6 ± 86.4) min in four groups,respectively (P < 0.05).The blood loss in four groups were (489.1 ± 285.6) ml,(431.8 ± 233.1) ml,(373.0 ±213.7) ml,(205.6 ± 137.8) ml,respectively (P <0.05).The transfusion rate in four groups were 18 (20.7%),16 (48.0%),15 (10.8%),14 (10.3%),respectively (P < 0.05).The mean time to flatus in four groups were (3.7 ±1.8)d,(3.6±1.0)d,(3.5±1.2)d,(2.2±1.7)d,respectively (P < 0.05).While ileal obstruction rate had no statistical difference in four groups [group A 17 cases(19.5%),group B 6 cases(18.2%),group C 27 cases(19.4%),group D 19 cases(14.0%),P =0.678].Urine leakage,intestinal leakage,lymphocyst were only occurred in group A [7 cases (8.0%),2 cases (2.3%),2 cases (2.3%)].Pyelonephritis was noticed in each group,including 14 cases(16.1%)in group A,2 cases(6.1%)in group B,9 cases (6.5%)in group C,6 cases(4.4%)in group D (P < 0.05).Hydronephrosis 6 months after surgery was observed in four groups,including 15 cases(17.2%)in group A,3 cases(9.1%)in group B,7 cases(5.0%)in group C,5 cases(3.7%)in group D (P < 0.05).Conclusions Ileal conduit without peritoneum closure would not increase the incidence of complications,on the contrary,it would relieve the tension of anastomosis,and reduce the occurrence of complications such as urine leakage.
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The surfaced enhanced Raman spectroscopy [SERS] of bladder cancer cells and tissues were measured in this paper Both depth SERS and map SERS of SCABER bladder cancer cells were measured with confocal Raman microscope using gold nanoparticles as the enhance substrate. We also measured SERS of normal bladder tissue and Wackier cancer tissue, and analyzed the difference of two different tissues. The SERS spectra of more samples need to be measured and analyzed for bladder cancer tissue and the normal bladder tissue in the future and the spectra will be helpful for bladder cancer diagnosis
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ObjectiveTo analyze the incidence of benign lesions in patients undergoing surgery for presumed renal cell carcinoma (RCC) and investigate the correlation of tumor size and histopathological characteristics.MethodsFrom Jan 2003 to Sep 2010,1531 patients (1042 males,489 females with average age of 55.1 years (15 -89 years) underwent nephrectomy.There were 1123 radical nephrectomies and 408 partial nephrectomies for solitary renal cortical neoplasms presumed to be RCC in preoperative imaging study.The pathological tumor size,the percentage of benign lesions and histologic subtypes were analyzed retrospectively.The correlation of Fuhrman grading and tumor size in clear cell type RCC and papillary RCC was investigated as well.Results Pathological examinations revealed that there were 81 (5.3%)benign lesions of 1531 patients.The incidence of benign lesions was 7.8% in renal masses smaller than 4.0cm,3.8% in masses with 4.1 - 7.0 cm,and 1.1% in masses larger than 7.0 cm ( P < 0.01 ).Angiomyolipoma was the most predominant histologic subtype in benign renal lesions with a frequency of 69.5%,52.6% and 33.3% in ≤4.0 cm,4.1 - 7.0 cm and > 7.0 cm subgroups,respectively.Oncocytoma was present in 13.6%,15.8% and 33.3% of the benign lesions in the above 3 subgroups (P =0.47).One thousand four hundred and fifty cases of malignancies (94.7%) were identified.The frequency of clear cell type RCC was 91.7% in malignant tumors smaller than 4.0 cm,88.1% in 4.1 - 7.0 cm malignancies,and 77.6% in tumors >7.0 cm; the frequency of papillary RCC was 4.0%,4.2% and 7.7% in the above 3 subgroups,and the frequency of chromophobe cell RCC was 3.6%,5.2% and 6.3% accordingly ( P <0.01 ).One thousand three hundred and seventeen cases of clear cell type RCC and papillary RCC with definite Fuhrman grading were identified.The probability of high grade tumors increased with size,while the probability of low-grade lesions decreased (r =0.94,P < 0.01 ),especially for tumors smaller than 11.0cm.ConclusionsPatients in the present study population show a low incidence of benign renal lesions.Benign lesions are less common in larger tumors than in smaller ones.The proportion of clear cell type RCC decreases in larger tumors,however papillary RCC and chromophobe cell RCC are increasing.The probability of high-grade tumors increases with size.The correlation between tumor size and histopathological characteristics may be helpful in patients counseling and decision-making.
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Objective To study the evolution of renal cell carcinoma treated in a single institution over the past 12 years.Methods A total of 1923 patients with renal cell carcinoma surgically treated from 1999 to 2010 were included in this study.Age at diagnosis,gender,symptoms,tumor size,TNM stage,histological subtype,Fuhrman grade and type of treatment were compared among 3 periods (Period 1:1999-2002,Period 2:2003-2006,Period 3:2007-2010).Results The number of patients grew fasty from 267 cases in the Period 1 to 1092 cases in the Period 3.The incidentally diagnosed cases increased significantly from 49.8% to 73.6% (P <0.01),while the mean age of patients at diagnosis,the male to female ratio and the proportion of young (<40 years old) patients were not statistically different.The tumor size at diagnosis gradually decreased from 6.1 cm to 4.8 cm (P < 0.01),and the proportion of small tumors less than 4 cm increased remarkably from 30.3% to 54.4% (P < 0.01).Concerning the surgical approach,open surgery decreased from 98.5% to 73.8% (P < 0.01),and laparoscopic surgery increased from 1.50% to 26.2% (P < 0.01).Overall,the rate of nephron-sparing surgery increased from 5.2% to 34.7% (P <0.01) in all cases.The use of nephron-sparing surgery increased significantly from 17.9% to 54.7% in T1a subset and from 0.00% to 14.8% in T1b subset respectively (P < 0.01).Furthermore,radiofrequency ablation was applied and the percent of this approach reached 2.47% in Period 3.Conclusions The evolution of clinical-pathological characteristics and surgical treatment for renal cell carcinoma in a single institution is apparent over the last 12 years.With the increase of incidentally diagnosed cases and small renal tumors,nephron-sparing surgery has been widely performed in T1 subset instead of traditional radical nephrectomy.
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Objective To discuss the feasibility and benefits of staged ureteroscopic laser lithotripsy in complicated cases. Methods From May 2005 to May 2008, the staged ureteroscopic procedure was done in 56 cases for ureteric stricture, kinking, spasm or high mobility of ureteric mucosa. Encountering difficulties, with the guide wire settled in place, the endoscopic procedure was ended and a ureteral stent was set. A second ureteroscopic procedure was carried out two weeks later. Results There was no difficulty for the insertion and the advancing of the ureteroscope two weeks later in all 56 cases. Among the 41 cases previously having the ureteric calculi, the stone was pushed into the kidney by the stent in 16 cases. There was no surgical complication during the second procedure. After three months the complete evacuation rate of the calculus was 96.4%. No patient experienced a fever >39.1 ℃ after the first attempt. Conclusions For complicated cases, such as ureteric stricture, spasm, kinking and high mobility of the ureteric mucosa which hinder the safe advancing of the ureteroscope, staged ureteroscopic procedure might be a safe and effective choice.
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Objective To study the natural history of renal cell carcinomas associated with von Hippel-Lindau disease (VHL). Methods An active surveillance strategy was carried out on 11 VHL cases(5 males and 6 females with average age of 45 years)with 32 renal masses. The mean maximum diameter of these masses at initial diagnosis was 2. 5 cm ranging from 0. 5 to 6.2 cm. Clinical materials, radiographic, and pathologic records were reviewed to determine tumor growth rate, subsequent interventions and outcome of follow-up. Results During a median follow-up of 70 months (range 32 to 258 months), bilateral solid renal tumors developed in 6 patients;13 surgical interventions were performed in 8 cases;tumor local recurrence occurred in 4 cases;3 cases died (2 of metastasis diseases and 1 of an unrelated disease) ;8 cases survived with 1 case taking regular hemodialysis.The median follow-up duration for 32 renal masses was 51 months (range 19 to 106 months). The mean tumor growth rate observed were 0. 55 cm/year (range 0. 04 to 1.75 em/year). Three tumors grew faster (1.13-1.75 cm/year), and the other 29 tumors grew slower (0. 17-0.88 cm/year).Among the 3 tumors, 1 was found to be grade Ⅱ at pathologic examination and another developed metastasis. Progression to metastatic disease was found in 2 patients. At the last follow-up, 27 (84 %)tumors were larger than 3 cm and no metastasis disease developed among tumors less than 4 cm.Conclusions The majority of enhanced renal masses with VHL disease may still be indolent and do not metastasize during long period of follow-up even in tumors larger than 3 cm. Active surveillance appears to be a reasonable option for VHL patients with enhanced renal masses less than 4 cm.
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Objective To discuss the management of renal vein trauma in the percutaneous ne-phrostomy (PCN) procedure.Methods Three cases with renal vein trauma by PCN or malposition of nephrostomic catheter were reviewed.Case 1 was a patient with staghorn calculi.There was mas-sive hemorrhage after the puncture and the dilatation during PCN.Then the nephrostomy catheter was clamped.The post-operative CT scan showed the nephrostomy catheter passed the inferior vena cava to the right external jugular vein.Case 2 was a patient with a 3 cm calculus in the inferior calice of the right kidney.A massive haemorrage occurred after the dilatation by the 16 F sheath guided by ultra-sound during PCN.The nephrostomic catheter was found in the renal vein by X-ray film.Case 3 was a patient with bilateral hydronephrosis complicating chronic renal failure,which caused by the meta-static of the gastric carcinoma.After the puncture,the massive hemorrage appeared and a nephros-tomic catheter was placed and then clamped.The catheter was seen in the renal vein confirmed by the X-ray.For all 3 patients,the catheter was withdrawn carefully monitored by the X-ray until the place of the renal vein perforation during the first 24-48h.Then it was withdrawn 3 to 4 cm each time un-til reach the pelvic.Results The hemorrhage was well controlled and nobody needed the surgical in-tervention.There was no renal function aggravation in these 3 patients.Conclusions The renal vein trauma during the echo-guide PCN procedure can be treated by clamping the nephrostomy catheter and withdrawing it gradually.Thus,the surgical intervention can be avoided and this method will not im-pair the renal function.
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Objective To study the histological classification,clinical stage,histological grade and prognosis of renal cell carcinoma by analyzing the records of the patients in Shanghai Renji hospital. Methods A consecutive series of 435 patients with renal cell carcinoma between 2003 and 2005derived from the renal cancer database were reviewed clinically and pathologically.The 1997 version of WHO histological classification for renal epithelial tumor,the 2002 version of AJCC clinical TNM staging system and the 1982 version of Fuhrmaffs system for nuclear grade were used.By survival analysis of 57 cases with advanced renal cell carcinoma using Kaplan-Meier method prognostic factors were confirmed using logrank test. Results Of a total 435 patients,cases were classified into 10(accounting for 2.4%of renal cell tumors)hereditary renal cancer in VHL disease,372(85.5%)clear cell renal cell carcinoma(CCRCC),13(3.0%)papillary renal cell carcinoma(PRCC),18(4.1%)chromophobe renal cell carcinoma(CRCC),4(0.9%)oncocytoma,4(0.9%)carcinoma of the collecting ducts of Bellini(CCDB),and 14(3.2%)renal cell carcinoma unclassified.There were 335(77%)patients undergone radical nephrectomy,74(17%)nephron sparing surgery and 26(6%)others,such as palliative nephrectomy.The patients with VHL disease come from 5 Chinese kindred and all had bilateral clear cell renal cell carcinomas and multifocal renal cysts.There were 7 paients of stage Ⅰ and 3 cases of stage Ⅱ and 6 cases of grade Ⅰ and 4 cases of grade Ⅱ.Genetic test revealed that all patients had VHL gene mutation.4 patients had recurrence while no evidence of local advance and distant metastasis were found during a mean of 28.6 months.Patients with chromophobe RCC are all of stage Ⅰ and 5 cases of grade Ⅰ and 13 cases of gradeⅡ.All patients are alive without recurrence or metastasis during a mean of 19.8 months.Collecting ducts RCC all presented with stage Ⅰ but grade Ⅲand with the median survival only 11.3 Months.Of clear cell and papillary RCC,260(67.6%),64(16.6%),32(8.3 %),29(7.5%)were stage Ⅰ,Ⅱ,Ⅲand Ⅳ,and of stage Ⅰ patients 147(38.2%),113(29.4%)were T1a and T1b respectively.124(32.2%),219(56.9%),40(10.4)and 2(0.5%)were grade Ⅰ,Ⅱ,Ⅲ,Ⅳ,respectively.Median survival of 57 advanced RCC is 16.0±1.3months,1-year survival is 55%,and 2-year survival is 31%,respectively.By using logrank test,clinical stage(<0.01),tumor size(<0.01),lymphadenopathy(<0.01),metastasis(<0.01)and tumor grade(<0.01)were anatomical and histological prognostic factors for advanced RCC. Coneluslons Different RCC subtypes have different clinical course.The RCC patients in VHL disease have VHL gene mutation and the tumors are often multifocal,bilateral,clear cell type with a low stage and grade which often recurrence but without metastasis.Chromophobe RCC may have a favorable prognosis but collecting duct RCC poor prognosis.In anatomical and histological level,clinical stage,tumor size,lymphadenopathy,metastasis and tumor grade are prognostic factors of survival for advanced RCC.
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<p><b>OBJECTIVE</b>To investigate an effective method to produce large numbers of pure corporal smooth muscle cells in vitro according to the requirement of study.</p><p><b>METHODS</b>In this study, we used the primary tissue culture technique to isolate and culture the corpus cavernosum smooth muscle cells (CCSM) from human males with normal erectile function and New Zealand white rabbits. The cells were identified in regard to morphological and growing characteristics via immunohistochemical methods (including alpha-smooth muscle actin, desmin, myocin and factor VIII related antigen), special dye techniques (including Masson and Van Gieson) and transmission electron microscope.</p><p><b>RESULTS</b>CCSM were isolated and cultured successfully with high purity. Morphologically, the cells were spindle shaped and grow on top of each other, resembling a "hill and valley" in appearance. When characterized in immunohistochemistry, the cells were stained with alpha-smooth muscle actin, desmin and myocin, but not with anti-factor VIII, an endothelial marker.</p><p><b>CONCLUSION</b>The CCSM, which can be isolated and cultured successfully, may be used for further studying their biological function. The CCSM cultured in vitro was proved to be useful to evaluate and investigate the effect of some new medicine for penile erection. There is also a clinical and theoretical significance in further studying the experimental mechanisms of erectile dysfunction.</p>
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Animals , Humans , Male , Rabbits , Cell Division , Cells, Cultured , Erectile Dysfunction , Immunohistochemistry , Myocytes, Smooth Muscle , Chemistry , Cell Biology , Penis , Cell BiologyABSTRACT
Objective To evaluate the efficacy of the flexible ureteroscopy and Holmium and FREDDY laser lithotripsy for renal calculi at various locations.Methods From May 2002 to May 2007,338 cases of renal calculi(sized less than 20 mm in diameter)were treated by flexible ureteroscopy and laser lithotripsy in our hospital.The data of the patients were analyzed retrospectively.Among the cases,the calculi were located at the upper or middle calyx or the renal pelvis in 288 patients,at the lower calyx in 37,and in multiple calyxes in 13.All the patients received KUB and IVU before the procedures.With the TerumoTM settled in place,a F8/9.8 Wolf rigid ureteroscope was inserted to observe and dilate the ureteral lumen.Then,an Olympus P3 6.9F flexible ureteroscope was used.When the insertion of the rigid ureteroscope was difficult,a re-ureteroscopy would be tried 2 weeks later with a pig-tail stent in place.The WOM U-100 FREDDY laser and the Lumenis Holmium laser were used to perform the procedure and a pig-tail stent would be set at the end of the procedure.The urethral catheter was removed in the first postoperative day and an intravenous antibiotic prophylaxis was administrated during the first 2 days postoperatively.A follow-up by KUB or non-contrast CT scan was done 4 weeks after the procedure to evaluate the result of the endoscopic nephrolithotripsy.Any residual calculi larger than 4 mm in diameter was taken significant.Results In 28 patients the rigid ureteroscope or the ureteral sheath couldn't be inserted in the first time,and the success rate of the ureteroscopic insertion was 91.7%(310/338).The re-ureteroscopy was successful in the patients after 2 weeks.The calculi were detected in 97.3%(329/338)of the patients,and the procedures succeeded in 306 of them(306/329,93.0%).The success rate of laser nephrolithotomy was 78.0%(32/41)for the lower calyx calculi,which was significantly lower than that for the middle,upper calyxes or renal pelvic calculi 95.1%(274/288),?2=13.601,P=0.000].After 4 weeks,the total evacuation rate of the calculi was 87.6%(296/338).For the calculi in the upper or middle pole or in the renal pelvis,the complete evacuation rate was 90.1%(264/293),which was significantly higher than that for the lower pole 71.1%(32/45),?2=12.929,P=0.000].No patient had ureteric perforation or active bleeding after the surgery.The mean operation time was 35 min(12-55 min).After the operation,11 cases developed nephritic colic.None of them had septicemia or acute renal failure.Gross hematuria disappeared in 1-2 days postperation.Conclusions The flexible ureteroscopy and Holmium and FREDDY laser lithotripsy are safe and effective for renal calculi sized less than 20 mm in diameter,especially for those in the upper,middle poles and renal pelvis.A re-ureteroscopy with the pig-tail stent in place is suggested in two weeks after the failure of the first procedure.