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131.
Santis WF Sullivan MP Gobet R Cisek LJ McGoldrick RJ Yalla SV Peters CA 《The Journal of urology》2000,163(3):980-984
PURPOSE: Ureteral dysfunction is a significant sequela of congenital bladder outlet obstruction. However, the structural and functional alterations associated with ureteral dysfunction are not well defined. A model of fetal bladder obstruction in sheep was used to characterize the changes in ureteral smooth muscle, extracellular matrix (ECM) and functional properties in response to bladder outlet obstruction. MATERIALS AND METHODS: Partial bladder outlet obstruction was created in fetal sheep at gestational age 95 days via placement of a metal ring around the proximal urethra as well as ligation of the urachus. Ureters were harvested at 109 and 135 days (full term = 140 days) to determine the relative composition of smooth muscle, ECM and urothelium by morphometric analysis and to measure DNA and protein concentrations. Ureteral tissue from 135 day gestation obstructed and control sheep was harvested and immediately placed in Krebs solution. Smooth muscle strips (2-3 mm. x 7-8 mm.) were suspended in organ baths. The frequency and amplitude of spontaneous ureteral contractions was as well as the response to electric field stimulation (EFS) were determined. RESULTS: Bladder outlet obstruction caused a significant increase in ureteral weight, smooth muscle mass and total ECM at both 109 and 135 days gestation. Total ureteral DNA was greater in obstructed compared with sham ureters at 135 days gestation. Obstructed ureters demonstrated greater amplitude and frequency of spontaneous contractions as well as more pronounced response to EFS when compared to sham ureters. CONCLUSIONS: The fetal ureter responds to bladder obstruction with smooth muscle hyperplasia and hypertrophy which is associated with increased spontaneous activity and augmented response to EFS. ECM content is markedly increased indicating a shift in the balance of connective tissue synthesis and degradation. Congenital post-obstructive ureteral dysfunction therefore appears to be the result of dysregulated smooth muscle cell growth and altered ECM homeostasis producing abnormal ureteral contractility. 相似文献
132.
Cell-cell adhesion molecules and signaling intermediates and their role in the invasive potential of prostate cancer cells 总被引:1,自引:0,他引:1
PURPOSE: The highly variable natural history of prostate carcinoma may be reflected in heterogeneity of invasive potential between tumors. MATERIALS AND METHODS: We have examined two prostate cancer cell lines of low invasive potential (CAHPV10 and PZHPV7) and three cell lines of high invasive potential (DU-145, PC-3, LNCapFGC), to determine whether specific adhesion molecule profiles correlated with their invasive behavior. RESULTS: Using an in vitro invasion assay, we demonstrated that DU-145, LNCapFGC and PC-3 cells were highly invasive compared with CA-HPV-10 and PZ-HPV-7 cells. LNCapFGC cells expressed high levels of E-cadherin, alpha-, beta- and gamma-catenin, desmoglein, desmoplakin and GSK3beta using immunoblotting. This was, in general, comparable to immunohistochemical staining. PC-3 cells had no E-cadherin or alpha-catenin, but expressed a high level of the HGF/SF receptor c-Met. In contrast, DU-145 cells were found to express E-cadherin and low levels for all other protein molecules, except c-Met. The DU-145 cell line also lacked alpha-catenin expression. In CA-HPV-10 and PZ-HPV-7 cells, there was no detection of APC, PECAM-1, P-cadherin or Wnt-1. DU-145, LNCapFGC and PC-3 cells formed cell-cell aggregates, which were reduced by inclusion of anti-E-cadherin antibody and the motogen HGF/SF. CONCLUSION: These results show that prostate cancer cells exhibit a diverse expression of cell-cell adhesion molecules and their signaling intermediates. The expression of these adhesion molecules bears an important relationship with the invasive phenotype of these cells. 相似文献
133.
Prospective, case matched comparison of hand assisted laparoscopic and open surgical live donor nephrectomy 总被引:13,自引:0,他引:13
PURPOSE: The technical difficulty of standard laparoscopic live donor nephrectomy has limited its application. Hand assistance, which takes advantage of the incision necessary for organ removal, facilitates laparoscopy without significant impact on patient recovery. We prospectively compared open surgical and hand assisted laparoscopic donor nephrectomy. MATERIALS AND METHODS: Our first 10 laparoscopic live donor nephrectomies were matched with 40 open donor nephrectomies by gender, age and body mass index. Data were obtained by pain scales, SF-12 survey instruments, questionnaires and chart abstraction. RESULTS: Operative time was longer for the laparoscopic approach (mean 95 versus 215 minutes). However, laparoscopic group patients had a shorter hospital stay compared to those undergoing open surgery (mean 2.9 versus 1.8 days), returned sooner to nonstrenuous activity (mean 19.0 versus 9.9 days) and reported less pain 6 weeks postoperatively (mean 2.3 versus 0.6) (p =0.03 for all). There were no differences between groups in terms of donor complications, allograft function and ureteral complications. Mean hospital cost was 23% greater in the laparoscopic group (p = 0.005) but global cost, which accounted for estimated loss of income from work during the recovery period, was only 15% greater (p = 0.10). Mean operative time was significantly improved for our second compared to our first 5 laparoscopic group patients (177 versus 254 minutes). CONCLUSIONS: Laparoscopic live donor nephrectomy appears to be a safe and effective alternative to open donor nephrectomy. Indexes of patient recovery suggest patient morbidity similar to that reported following standard laparoscopic donor nephrectomy and significantly less than after open nephrectomy. Improvement in operative time in the first 10 cases suggests that hand assistance "shortens" the learning curve, which might encourage more surgeons to offer laparoscopic live donor nephrectomy. 相似文献
134.
PURPOSE: We analyze a group of patients who presented with mechanical dysfunction of the reservoir and/or efferent limb of a continent colonic urinary diversion, and establish an evaluation and management algorithm. MATERIALS AND METHODS: A total of 16 patients with a mean age of 58 years and 1 or more symptoms related to continent colonic urinary diversion were evaluated. Presenting symptomatology included difficult catheterization in 8 cases (50%), disabling incontinence in 8 (50%) and recurrent urinary tract infections in 6 (37.5%). All patients had normal, nonobstructed, nonrefluxing upper tracts and none presented with stone disease. Urological evaluation consisted of catheterization, fluoroscopy and urography of the pouch, retrograde urography of the external limb and urodynamics (enterocystometrogram and outlet pressure profilometry). RESULTS: Of the 8 patients with difficulty with catheterization 4 had stomal stenosis, 2 had an elongated and redundant external limb, and 2 had a false passage. Diagnosis was established by the inability to catheterize, fluoroscopy of the pouch and retrograde urography. Disabling incontinence occurred in 8 patients, including 7 who presented with an incompetent outlet and 2 with high pressure intestinal contractions of the reservoir. The aforementioned abnormalities were diagnosed by a combination of retrograde urography, urography of the pouch and urodynamics. Recurrent symptomatic urinary infections were observed in 5 patients of the previous groups and in another with an hourglass reservoir, which was primarily diagnosed by urography of the pouch. Surgical correction in 15 patients included outlet reinforcement, reservoir revision, stomal or external limb revision and conversion to a urinary conduit. Surgical treatment was successful in 14 of 15 patients (93%). CONCLUSIONS: Catheterization difficulty requires retrograde urography to define possible anatomical abnormalities (false passage, conduit elongation) if catheterization and fluoroscopy of the pouch do not demonstrate stomal stenosis. Urinary incontinence benefits from enterocystometry and outlet pressure measurement to determine reservoir and external limb function. Recurrent urinary tract infections not related to ureteral obstruction or reflux requires fluoroscopy of the pouch and external limb to determine abnormalities in patients with detubularization and localization of areas of urine pooling. 相似文献
135.
PURPOSE: We prospectively examined the incidence of recurrence and progression in patients with stage pT1, grade 3 carcinoma of the bladder following complete transurethral resection of the bladder tumor and adjuvant immunotherapy with bacillus Calmette-Guerin (BCG). MATERIALS AND METHODS: Between July 1987 and March 1999, 123 patients presenting to our clinic with superficial urothelial carcinoma (stage pT1, grades 1 to 3) received adjuvant intravesical immunotherapy with BCG after histologically confirmed complete transurethral tumor resection. Disease was stage pT1, grade 3 in 44 patients (36%). Median followup was 28 months (mean 43, range 5 to 141). RESULTS: Of the patients 36 (82%) with bladder preservation remained tumor-free during followup after 1 or 2 cycles of BCG. Superficial tumor recurred in 5 patients (11%) and muscle invasive progression was noted in 7 (16%). Radical cystectomy was performed in 4 cases (9%). Of the patients 5 (11%) died of cancer. Tumor-free survival for all patients was 89% (39 of 44). CONCLUSIONS: Adjuvant immunotherapy with BCG after complete transurethral resection of bladder tumor represents a highly effective primary treatment of stage pT1, grade 3 carcinoma of the bladder. Immediate radical cystectomy does not appear necessary. 相似文献
136.
PURPOSE: We evaluate our experience with de novo reimplantation of the artificial genitourinary sphincter with a particular emphasis on mechanical and nonmechanical failure rates. De novo reimplantation is defined as implantation of an artificial sphincter following removal of a previously placed sphincter for erosion and/or infection and a waiting period of several months. MATERIALS AND METHODS: A retrospective analysis of more than 400 patients with an artificial sphincter revealed 23 who underwent de novo reimplantation between January 1983 and October 1998. All patients were men with a mean age of 66.5 years (range 16 to 88) and all had a urethral cuff. Reasons for cuff removal were erosion in 12 cases (52.2%), infection in 10 (43.5%) and intraoperative urethral injury in 1 (4.3%). Mean waiting period was 6.8 months (range 1.5 to 32) between explantation and de novo reimplantation. Mean followup was 32.6 months (range 1 to 108). RESULTS: Of the 23 patients 20 (87%) had no mechanical or nonmechanical failures and 3 (13%) had nonmechanical failures, including 2 patients (8.7%) whose cuff eroded into the urethra and 1 (4.3%) who had recurrent urinary incontinence which was successfully treated with implantation of a tandem cuff. There were no mechanical failures or infections in this group of patients. CONCLUSIONS: Our study suggests that de novo artificial sphincter reimplantation is an excellent treatment option. It is safe and associated with complication rates that are comparable to those of primary implantation. 相似文献
137.
Montorsi F Salonia A Maga T Bua L Guazzoni G Barbieri L Barbagli G Chiesa R Pizzini G Rigatti P 《The Journal of urology》2000,163(6):1704-1708
PURPOSE: We assessed the long-term outcome of plaque incision and vein grafting in select patients with Peyronie's disease by extensive preoperative and postoperative subjective and objective analysis. MATERIALS AND METHODS: From January 1995 to June 1998, 50 men 28 to 62 years old (mean age 44) underwent surgery. Patients were evaluated preoperatively, 3 months after surgery and at a mean long-term followup of 32 months by sexual history, physical examination, determination of penile length and degree of curvature, dynamic color power Doppler sonography of the penile vessels and nocturnal RigiScan* evaluation for 3 nights. Study inclusion criteria were penile curvature 45 degrees or greater that made vaginal intromission impossible, stable disease for at least 6 months, patient reported normal penile rigidity, normal penile hemodynamics on color power Doppler ultrasound, normal nocturnal penile rigidity with at least 1 erection nightly (including base and tip rigidity greater than 60%, and a duration of 10 minutes) and absent base-tip discrepancies. Plaque was usually approached via a combined subcoronal and midline sagittal scrotal incision. Maximal rigidity was created intraoperatively and 1 to 3 plaque incisions were made. Saphenous vein patches were then grafted at the incision sites. Postoperatively patients were systemically treated with neurotrophic factors and low molecular weight heparin. Local vacuum supported corporeal stretching was done and weekly alprostadil injections were given to optimize corporeal oxygenation. RESULTS: At long-term followup complete penile straightening was achieved in 40 cases (80%), minor residual curvature of 30 degrees or less persisted in 7 (14%) and significant disease recurred in 3 (6%). Penile rigidity was equal to that preoperatively in 47 patients (94%), while 3 (6%) reported clinically significant decreased potency. Penile length was equal to that preoperatively in 30 patients (60%), while 20 (40%) noticed slight penile shortening. Postoperatively penile color power Doppler sonography showed vascular impairment in 5 men (10%) and nocturnal RigiScan testing revealed a significant decrease in nightly erections in 5 (10%). Surgical complications included penile hypoesthesia in 1 case (2%), penile hematoma in 2 (4%), wound infection in 1 (2%) and glandular ischemia in 1 (2%). CONCLUSIONS: Plaque incision and vein grafting achieved satisfactory clinical results in the majority of patients with severe and stable Peyronie's disease, intact penile rigidity preoperatively, normal penile color power Doppler ultrasound and normal nocturnal RigiScan testing. 相似文献
138.
Diagnostic findings from testis fine needle aspiration mapping in obstructed and nonobstructed azoospermic men 总被引:3,自引:0,他引:3
PURPOSE: Although helpful for defining extratesticular obstruction, the testis biopsy offers limited information on nonobstructive azoospermic testes. Guided by diagnostic biopsies, testis sperm extraction procedures fail in 25% to 50% of patients with nonobstructive azoospermia, largely because it is clinically difficult to know where sperm are located. To provide a more complete assessment of spermatogenesis in nonobstructive azoospermic patients and to simplify the confirmation of sperm production in men with obstruction, we use a systematic, fine needle aspiration "mapping" procedure. We summarize the diagnostic findings in a series of azoospermic men. MATERIALS AND METHODS: From 118 azoospermic infertile men (22 with obstructed and 96 with nonobstructed azoospermia) fine needle aspiration data were used to generate location specific, sperm frequency maps for obstructed and nonobstructive azoospermic testes to determine if "sperm rich" locations existed. RESULTS: Fine needle aspiration map analysis revealed that all aspiration locations from obstructed cases showed sperm. In men with nonobstructive azoospermia, sperm was identified in the right testis in 134 of 652 (20.5%) and in the left testis in 151 of 716 (21.1%) separate aspirations. Rates of sperm detection among various intratesticular sites were not statistically different. In 27.1% of cases the fine needle aspiration map found sperm in men with sperm negative biopsies. The likelihood of heterogeneity in fine needle aspiration sperm findings was 25% within individual nonobstructive azoospermic testes and 19.2% between testis sides. At post-procedure followup of 88 patients (74%), no clinical or surgical complications were observed. CONCLUSIONS: Testis fine needle aspiration mapping is a simple, reliable and informative diagnostic tool in the evaluation of azoospermic infertile men. 相似文献
139.
PURPOSE: We performed a prospective study to determine the incidence and spectrum of metabolic abnormalities predisposing to stone formation in patients with ureteropelvic junction obstruction and renal calculi. MATERIALS AND METHODS: A total of 47 consecutive patients with congenital ureteropelvic junction obstruction underwent metabolic evaluation of stone risk factors. Of these patients 21 had associated stones (study group), while 26 did not (control group). Logistical regression, Wilcoxon rank sum and Fisher's exact tests were performed to determine whether there was a significant difference between these groups in regard to the presence of metabolic risk factors. RESULTS: Demographically and symptomatically the 2 groups were equivalent except that the study patients were older. The 24-hour urinary excretion of calcium was significantly higher in study than in the control patients (p = 0.007). While the incidence of hypercalciuria and hyperuricosuria was also higher in the study population, these differences were not significant (p = 0.08 and 0.07, respectively). CONCLUSIONS: Metabolic abnormalities predisposing to stone formation are present more frequently in patients with ureteropelvic junction obstruction who have associated stones compared to those who do not. As such, urinary stasis alone does not explain stone formation in these cases. Rather, the local physiological environment of urine likely has a predisposing role. In addition to restoring unobstructed urinary flow, consideration should be given to metabolic evaluation and prophylactic treatment for affected patients. 相似文献
140.
通过对重庆医科大学各类重点实验室现状的概括和分析,找出存在的主要问题,并提出具体的改进措施。 相似文献