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Shinichi Ohshima

Publications and source records attributed to Shinichi Ohshima.

At least 19 recordsLinked to original sources
PubMed2006

Constructing a tissue-engineered ureter using a decellularized matrix with cultured uroepithelial cells and bone marrow-derived mononuclear cells.

This study investigated the efficacy of the ureteral decellularized matrix (UDM) as a scaffold material for a tissue-engineered ureter, and the effect of bone marrow-derived mononuclear cells (BM-MNC) on the neovascularization of the scaffold. Canine ureters were treated with deoxycholic acid to remove all cells. Uroepithelial cells (UEC) were obtained from canine bladders, cultured, and then seeded onto the inner surface of the UDM before transplantation into the subcutaneous space of nude mice or the omentum of nude rats. The cultured UECs began showing vacuolar degeneration 3 days after transplantation and gradually disappeared thereafter. To facilitate neovascularization in the implant, BM-MNCs were seeded around the UDM before transplantation. This facilitated the survival of the UECs, which formed three to five cellular layers after 14 days. The mean microvessel density was significantly increased in tissues seeded with BM-MNCs. However, cell-tracking experiments revealed that the increased number of capillaries in the experimental group was not due to the direct differentiation of transplanted endothelial progenitor cells. Our results demonstrate that the UDM is a useful scaffold for a tissue-engineered ureter, especially when seeded with BM-MNCs to enhance angiogenesis.

Animals↗
PubMed2006

Pathophysiology and subjective symptoms in women with impaired bladder emptying.

AIM: To assess the pathophysiology and subjective symptoms in female patients with impaired bladder emptying. METHODS: Eighty-three consecutive female patients attending a urology clinic with postvoid residual urine of more than 100 mL were recruited. Free uroflowmetry, measurement of postvoid residual urine and pressure-flow study were performed in all patients. The detailed assessment of subjective symptoms and their bothersomeness to the patients were assessed using a self-administered questionnaire comprising 12 items: five associated with voiding symptoms, five with storage symptoms, and two with discomfort and pain on voiding. The questionnaire was applied to 83 patients with impaired bladder emptying, 41 patients with urinary incontinence, and 21 normal controls. RESULTS: Although 77% of the patients with impaired bladder emptying consulted a urology clinic because of voiding symptoms, the remaining 23% complained of storage symptoms or symptoms other than lower urinary tract symptoms (LUTS). The pressure-flow study revealed the pathophysiology of impaired bladder emptying as impaired detrusor contraction in 68 patients (81.9%), and bladder outlet obstruction in 12 patients (14.8%). The assessment of subjective symptoms using the questionnaire revealed that the patients with urinary incontinence showed a high frequency only in storage symptoms; however, those with impaired bladder emptying revealed a high frequency not only in voiding but also in storage symptoms. CONCLUSIONS: Female patients with impaired bladder emptying present with a wide range of lower urinary tract symptoms associated with both voiding and storage symptoms. To determine an appropriate treatment modality, the correct diagnosis of the underlying pathophysiology of impaired bladder emptying by pressure-flow study is of primary importance.

Adult↗
PubMed2006

[Endoscopic trigonoplasty II for primary vesico-ureteral reflux].

PURPOSE: We report a technique and outcome of endoscopic trigonoplasty II (ET II), anti-reflux surgery via a transvesicostomy transurethral approach and discuss its usefulness. MATERIALS AND METHODS: Fifteen female patients, aged 5 to 64, with 23 refluxing ureters (grade I : 5, II : 2, III : 14, IV : 2) underwent the ET II. The principle of this surgery is tightening the muscular backing and elongating the intramural ureter. The operation consists of three steps: 1) two 5 mm locking trocars are placed into the bladder, 2) irrigating with 3% D-sorbitol solution, the bladder wall is incised upward along each side of the ureter using a resectoscope, to make a 2 to 3 cm U-shaped bladder flap including the ureter, 3) under a pneumobladder, the incised wall is sutured to make a muscular bed with a needle-holder via the urethra and forceps via the abdominal trocar. The U-shaped flap is fixed with two distal anchor sutures and four additional mucosal sutures. Urethral catheter is indwelled and the operation is finished. In recent four cases, we closed the tracts endoscopically. RESULTS: The average operative time was 144 minutes per ureter. In one patient with unilateral reflux, we switched to open surgery because of bleeding. Of 22 refluxing ureters, the reflux disappeared in 18 ureters (82%) and improved grade III to I in 1 ureter (5%) after 3 months and disappeared in 19 ureters (86%) after 12 months postoperatively. Ureteral injury was occurred in 3 patients during the transurethral incision of the bladder. Though we repaired it by placing a double-J stent in the 2 patients, reflux recurred in 12 months postoperatively in one of them. In the other patient cystoscopy revealed a vesicoureteral fistula in the injured portion. She subsequently underwent successful open Politano-Leadbetter ureteroneocystostomy. The average duration of indwelling catheter was shortened from 4.3 to 3.0 days by closing the tracts endoscopically. CONCLUSIONS: The overall cessation rate of the ET II was inferior to those of open anti-reflux surgeries or laparoscopic extravesical ureteral reimplantation. We do not recommend ET II for vesicoureteral reflux.

Adolescent↗
PubMed2005

Factors predicting long-term graft survival after kidney transplantation: multicenter study in Japan.

A multicenter retrospective study was conducted in 936 living donor kidney transplant recipients treated with cyclosporine (CsA) or tacrolimus (FK) from April 1982. The influences of acute rejection, hyperlipidemia, and hypertension were estimated by Kaplan-Meier's analysis and Wilcoxon's analysis. Of 916 recipients, 532 (58.1%) had acute rejections. The 5- and 10-year graft survival rates in the recipients with acute rejection were 75.2% and 55.2%, respectively. The corresponding rates of the recipients without acute rejection were 80.2% and 70.6%, respectively. The graft survival rate was worse in recipients with late-phase rejection and multiple rejection episodes (p < 0.00006). Of 451 recipients, 176 (39.0%) had hypercholesterolemia 3 years after kidney transplantation. The 5- and 10-year graft survival rates in the recipients with hypercholesterolemia were 88.7% and 68.7%, respectively. Those of the recipients without hypercholesterolemia were 95.2% and 83.9%, respectively. The graft survival rate in the recipients with hypercholesterolemia was lower than that in the recipients without hypercholesterolemia (p = 0.003). Of 323 recipients, 123 (38.1%) had hypertriglyceridemia 3 years after kidney transplantation. The 5- and 10-year graft survival rates in the recipients with hypertriglyceridemia were 93.7% and 80.5%, respectively. Those in the recipients without hypertriglyceridemia were 95.1% and 86.5%, respectively. The graft survival rate in the recipients with hypertriglyceridemia was lower than that in the recipients without hypertriglyceridemia (p = 0.371). Of 367 recipients, 151 (41.1%) had systolic hypertension 3 years after kidney transplantation. The 5- and 10-year graft survival rates in the recipients with hypertension were 85.6% and 64.7%, respectively. Those of the recipients without hypertension were 95.6% and 83.8%, respectively. The graft survival rate in the recipients with hypertension was lower than that in the recipients without hypertension (p < 0.001). Acute rejection, hyperlipidemia (hypercholesterolemia and hypertriglyceridemia), and hypertension are predictive factors for long-term graft survival. Especially the onset time, number of rejections, and efficacy of treatment for acute rejection would have a significant influence on long-term graft survival.

Adolescent↗
PubMed2005

The current status of perioperative chemotherapy for invasive bladder cancer: a multiinstitutional retrospective study in Japan.

BACKGROUND: We conducted a multiinstitutional analysis to clarify the clinical significance of perioperative chemotherapy, in invasive bladder cancers in Japan, and to identify the patient subpopulations who could benefit from perioperative chemotherapy. METHODS: A total of 913 consecutive patients aged less than 80 years who underwent radical cystectomy for invasive bladder cancer from 1990 to 2000 at 32 Japanese hospitals were retrospectively analyzed. Median follow-up was 3.8 years (range, 0.1 to 11.8 years). RESULTS: In total, 341 patients (37.3%) were treated with perioperative chemotherapy, including neoadjuvant chemotherapy (n = 174), adjuvant chemotherapy (n = 114), or a combination of both chemotherapies (n = 53). With cisplatin-based combination chemotherapy, the MVAC (methotrexate, vinblastine, doxorubicin, and cisplatin) regimen was the one most frequently used for perioperative chemotherapy, but the average number of cycles was distinctly less than that in reported randomized trials. MEC (methotrexate, epirubicin, and cisplatin) chemotherapy had efficacy similar to that of the MVAC regimen. On analysis of patients stratified by stage, the overall survival of patients with adjuvant chemotherapy was significantly better than that of those without adjuvant chemotherapy, in patients with pT2b, pN0 or pT3, pN0 (P = 0.016 or 0.020, respectively), but adjuvant chemotherapy had no, or the opposite, effect on patients with pT2a, pN0, pT4, pN0, or pTany, pN+. On the other hand, neoadjuvant chemotherapy provided a statistically significant survival benefit only for patients with clinical T3N0 (P = 0.015). Of note, in the high-risk subgroup, the overall survival rate for patients with complete response (CR) after neoadjuvant chemotherapy was significantly better than that of patients with partial response (PR) or no change (NC)/progressive disease (PD) (P = 0.043). CONCLUSION: In Japan, cisplatin-based combination chemotherapy has been the main modality adopted perioperatively for high-risk patients with radical cystectomy. This study's clinical results indicated that perioperative chemotherapy may improve survival in patients with T3N0 or pT2b/pT3, pN0 bladder cancer.

Adult↗
PubMed2005

Laparoscopic pyeloplasty using endoscopic GIA stapler for ureteropelvic junction obstruction.

PURPOSE: We applied laparoscopic pyeloplasty in 10 patients with ureteropelvic junction (UPJ) obstruction. To evaluate the efficiency and safety of this procedure using an endoscopic GIA stapler, the clinical outcomes and our procedures are presented. PATIENTS AND METHODS: From August 1996 to March 2003, eight female and two male patients with a mean age of 22.3 years suffering from UPJ obstruction diagnosed by various combinations of ultrasonography, excretory urography, retrograde ureteropyelography, CT, and MRI were treated with laparoscopic dismembered Anderson-Hynes pyeloplasty with resection of a dilated redundant renal pelvis. In six cases, an endoscopic gastrointestinal automatic stapler (Endo-GIA) was used. The procedure was performed via an extraperitoneal approach in two cases and a transperitoneal approach in eight. RESULTS: Laparoscopic pyeloplasty was successful in all patients, including the six treated using an Endo- GIA stapler. The mean operating time was 291 minutes, and the mean anastomotic time was 105 minutes, with a mean estimated blood loss of 44 mL. Postoperative complications occurred in five cases: anastomotic urinary leakage in two and pyelonephritis in three. The mean time to full convalescence in the entire series was 22 days. No urolithiasis occurred in the patients treated with the Endo-GIA stapler during the follow-up period of 2 to 76 (mean 22) months. CONCLUSIONS: Laparoscopic dismembered pyeloplasty including the Endo-GIA stapler technique is an efficient and safe procedure that provides excellent results for extrinsic or complicated UPJ stenosis. The risk of stone formation has not yet been determined.

Adolescent↗
PubMed2005

Relationship between prostate specific antigen and indexes of prostate volume in Japanese men.

PURPOSE: We determined the relationship between serum prostate specific antigen (PSA) and indexes of prostate volume in Japanese men, and compared that relationship with the one in white men. MATERIALS AND METHODS: Data on a clinical cohort of 535 Japanese men with at least moderate lower urinary tract symptoms (LUTS) and clinical benign prostatic hyperplasia were examined. PSA, and total and transition zone prostate volume were related to age and linear regression analyses were performed to analyze the relationship between PSA and volume indexes. RESULTS: The group of 535 men with a median age of 68 years had a median serum PSA of 1.5 ng/ml, and a median total and transition zone volume of 26.8 and 8.8 ml, respectively. PSA, total prostate volume and transition zone volume increased almost linearly with age. On univariate regression with age with each successive decade total prostate volume increased by 10.65% (95% CI 5.4 to 16.2), transition zone volume increased by 20.84% (95% CI 11.84 to 30.56) and the transition zone index increased by 3.1% (95% CI 1.66 to 4.57). On multivariate analysis the PSA-total prostate volume relationship was statistically independent of age. The study suggests that Japanese men might produce or release more PSA per unit prostate volume than white men. CONCLUSIONS: Japanese men with LUTS and clinical benign prostatic hyperplasia but no evidence of prostate cancer might produce and/or release more PSA per unit prostate volume than white men. To our knowledge the cutoffs for PSA and prostate volume to predict the response to LUTS therapy and the development of complications in Japanese men are unknown. Future studies in Japanese men are needed to identify these cutoffs.

Adult↗
PubMed2005

The long-term outcome of tacrolimus in cadaveric kidney transplantation from non-heart beating donors.

Tacrolimus (Tac), developed in 1990, has been applied as an immunosuppressive agent for liver, heart, and kidney transplantation and is known to have more powerful immunosuppressive effects than cyclosporine (CyA). To evaluate the efficacy of Tac in cadaveric kidney transplants from non-heart beating donors, we present the long-term outcome of patients receiving kidneys with ischemic damage, and compared it with that of CyA. Between July 1990 and December 2000, 55 patients with end-stage renal disease received kidneys from non-heart beating donors (Maastrichy category 3) and were treated with Tac and steroid immunosuppressive therapy. During the same period, we also performed 137 non-heart beating cadaveric renal transplants treated with CyA-based immunosuppressive therapy. The patient survival rate was 98% at 1 yr and 96% at 3-10 yr in the Tac group, and 97% at 1-3 yr, 93% at 5 yr and 85% at 10 yr in the CyA group. The graft survival rate was 91% at 1 yr, 80% at 3 yr, 63% at 5 yr and 34% at 10 yr in the Tac group, and 88% at 1 yr, 75% at 3 yr, 63% at 5 yr and 49% at 10 yr in the CyA group. There was no significant difference in either patient or graft survival rates between the two groups. Acute early rejection in the Tac group was less than that in the CyA group but acute tubular necrosis was the same in both groups. This indicates that Tac is available for cadaveric kidney transplants from non-heart beating donors. In conclusion, Tac is available as an immunosuppressive agent even for kidney transplants from non-heart beating donors.

Adult↗
PubMed2005

A prospective trial of steroid withdrawal after renal transplantation treated with cyclosporine and mizoribine in children: results obtained between 1990 and 2003.

A prospective trial of adrenocorticostertoid (steroid) withdrawal after pediatric renal transplantation was begun in 1990. Ninety-four pediatric renal transplant recipients were enrolled in our multicenter study. Immunosuppressive therapy with cyclosporine (CyA), methylprednisolone (MPL), and mizoribine (MZ) was started after transplantation. MPL was reduced to administration on alternate days in 69 patients (73.4%) and was withdrawn in 27 patients (28.7%). Rejection episodes occurred in nine patients (33.3%) after withdrawal of MPL. It occurred within 3 months after withdrawal of MPL in two patients and more than 6 months in the others. Among them, two patients lost the grafts. Thirteen-year patient survival rate and graft survival rate were 94.6 and 83.1%, respectively. Forty-four of the 94 patients reached their final height. Mean final height was 155.0 cm in males and 146.3 cm in females and their height standard deviation score was -2.6 s.d., the same as that at the time of transplantation. Management of growth retardation before transplantation and further reduction in the steroid dose after transplantation will increase the final height of children with chronic renal failure.

Adolescent↗
PubMed2005

Determination of the relative probability for prostate cancer to avoid unnecessary biopsy.

BACKGROUND: To investigate whether using a new concept of relative probability for prostate cancer (RPpca) can increase sensitivity and specificity in detecting prostate cancer. METHODS: For 217 patients with total prostate-specific antigen (PSA) level of 4-20 ng/mL, prostate volume and free to total PSA (F/T) ratio were measured. From the fitted curves between positive predictive values for prostate cancer and age, prostate volume, total PSA or the F/T ratio, each function predicting prostate cancer was determined. RPpca defined by the combined functions of age, prostate volume, total PSA and F/T ratio was calculated for each individual patient. The probability of prostate cancer was also calculated, using logistic regression analysis (LRPpca). Receiver-operating characteristic analysis was performed to elucidate the areas under the curve (AUC), sensitivities and specificities and cutoff values of the conventional and new parameters. Finally, we investigated the applicability of the above parameters in the other patient group using a different PSA assay kit (AxSYM). RESULTS: Although RPpca had the largest AUC in the total PSA range of 4-20 ng/mL, it did not reach statistical significance between RPpca and F/T ratio or LRPpca. The cutoff values of F/T ratio, LRPpca and RPpca were determined as 0.15, 0.12 and 0.20, respectively. Using these cutoff values in AxSYM data, RPpca had the highest sensitivity (91%) and specificity (57%). CONCLUSIONS: RPpca can provide more precise information to avoid unnecessary biopsy than LRPpca or F/T ratio. RPpca could be valuable to decide whether to perform prostate biopsy when using various PSA kits.

Adult↗
PubMed2005

Measurement of prostate specific antigen complexed to alpha1-antichymotrypsin to avoid unnecessary biopsy in patients with serum prostate specific antigen levels 4-20 ng/mL.

AIM: To investigate whether measuring prostate specific antigen complexed to alpha1-Antichymotrypsin (PSA-ACT) can increase sensitivity and specificity in detecting prostate cancer. METHODS: In this prospective study, we measured serum total PSA, PSA-ACT, free PSA, prostate volume and transition zone volume on 210 patients with total PSA level of 4-20 ng/mL. From fitted curves between positive predictive values for prostate cancer and age, prostate volume, transition zone volume, total PSA, PSA-ACT or F/T ratio, each function predicting prostate cancer was determined. Relative probabilities for prostate cancer (RPpca) which were defined by combined functions of age, F/T ratio, prostate volume or transition zone volume, and total PSA or PSA-ACT were calculated. Furthermore, using logistic regression, analysis was performed to determine the probability of prostate cancer. Receiver-operating characteristic analysis was performed to clarify the areas under the curve (AUC) for conventional single parameters, RPpca and logistic regression probability. RESULTS: F/T ratio showed the largest AUC among conventional parameters. The AUC of RPpca was larger than those of F/T ratio and logistic regression probability. RPpca using the functions of age, transition zone volume, PSA-ACT and F/T ratio showed the largest AUC and highest specificity at sensitivity 95% level, however, specificities at sensitivity 90% and 85% were identical to those of RPpca using the functions of age, prostate volume, total PSA and F/T ratio. CONCLUSIONS: RPpca using the functions of age, transition zone volume, PSA-ACT and F/T ratio was the best way to detect prostate cancer, however, the usefulness of PSA-ACT appears limited, considering the cost.

Aged↗
PubMed2005

Comparison of tamsulosin and naftopidil for efficacy and safety in the treatment of benign prostatic hyperplasia: a randomized controlled trial.

OBJECTIVES: To compare the efficacy and safety of two alpha1a/alpha1d adrenoceptor (AR) antagonists with different affinity for the alpha1AR subtypes, tamsulosin and naftopidil, in the treatment of benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: Patients with BPH were randomized to receive either tamsulosin or naftopidil. The primary efficacy variables were the changes in the total International Prostate Symptom Score (IPSS), maximum flow rate on free uroflowmetry, and residual urine volume. The secondary efficacy variables were average flow rate, changes in the IPSS storage score, IPSS voiding score, and quality-of-life (QoL) Index score, from baseline to endpoint (12 weeks). Data on all randomized patients were included in the safety analyses for adverse effects and changes in blood pressure. RESULTS: Of the 185 patients enrolled data for 144 who were eligible for inclusion in the efficacy analysis were analysed (75 from the tamsulosin and 69 from the naftopidil group). There was no significant difference in any variable at baseline between the groups. There were statistically significant improvements for all primary and secondary variables in both groups, except for residual urine in the tamsulosin group. However, there was no significant intergroup difference in the improvement of any efficacy variable between the groups. The adverse effects were comparable, with no significant differences in systolic and diastolic blood pressure after treatment in both groups. CONCLUSIONS: This study suggests that naftopidil is as effective and safe as tamsulosin. Both drugs were effective in improving storage and voiding symptoms. However, there was no difference in clinical efficacy or adverse effects between the alpha1 AR antagonists with different affinity to alpha1 subtypes, alpha1a and alpha1d.

Adrenergic alpha-Antagonists↗
PubMed2005

[Donor action program].

Recent advances of organ transplantation accelerated shortage of organs. Donor Action Program (DAP) was developed to establish a proper donation process in a hospital using total quality management methodology. It has been demonstrated effective in increasing donation and has been introduced in 23 countries. In Japan preliminary study demonstrated that (1) DAP could be implemented and was likely to increase donation in Japan, (2) Japanese healthcare staffs were likely to underestimate social needs and clinical results of transplantation and to be suspicious about brain death, (3) they had limited knowledge and experience in communicating with family members of the deceased, and their needs for education were not satisfied. In order to implement DAP in Japan, an organization which is responsible for data management and development for educational program should be considered with high priority.

Japan↗
PubMed2004

Clinical outcome of a large-scale multi-institutional retrospective study for locally advanced bladder cancer: a survey including 1131 patients treated during 1990-2000 in Japan.

OBJECTIVE: We conducted a multi-institutional analysis to establish the contemporary clinical outcome of invasive bladder cancer treated with radical cystectomy in Japan. METHODS: A total of 1131 consecutive patients who underwent radical cystectomy for invasive bladder cancer between January 1990 and December 2000 at 32 hospitals were retrospectively analyzed. RESULTS: Histopathological analysis demonstrated that 1042 patients (92.1%) harbored transitional cell carcinomas (TCCs), whereas 89 patients (7.9%) presented non-TCCs, including squamous cell carcinoma and adenocarcinoma. Pelvic lymphadenectomy was performed in 1013 patients in total, and pathologically confirmed lymph node metastases were found in 162 (16.0%). The overall survival at 5 years was 68.0% and most deaths (79.0%) occurred within 3 years. Multivariate analysis demonstrated that gender, clinical stage, pathological stage, lymph node involvement and lymph node dissection were the independent predictive factors for survival, whereas histological type, sex and grade had no significant impact on survival. CONCLUSIONS: These clinical results demonstrate that radical cystectomy with lymph node dissection results in good survival for invasive bladder cancer, providing standard data with which other forms of therapy can be compared.

Adult↗
PubMed2004

Laparoscopic partial nephrectomy for renal tumor: Nagoya experience.

OBJECTIVES: To clarify the indication for a vascular clamp during laparoscopic partial nephrectomy, the clinical results of 17 patients who underwent the procedure for small renal tumors were reviewed. METHODS: Seventeen patients with renal tumors were enrolled in our laparoscopic partial nephrectomy program between October 1999 and November 2003. During laparoscopy, a vascular clamp was used to remove the tumor mass and suture the incised renal parenchyma and urinary collecting system in 8 patients who had less-than-1-cm-thick renal parenchyma between the mass and the renal sinus or calices. In the remaining 9 patients, who had 1-cm-or-more-thick renal parenchyma between the mass and sinus or calices, renal bleeding was controlled using ultrasonic scissors, gauze tampon, argon beam coagulator, and fibrin glue. RESULTS: Sixteen patients were successfully treated with laparoscopy; one required conversion to open surgery because of uncontrollable bleeding. The average operative time was 4.5 hours, and average estimated bleeding volume was 301 mL. In the 8 patients requiring vascular clamping by forceps, the average ischemic time was 25 minutes. In all patients, the tumor mass was completely removed with negative surgical margins, and renal function was preserved. Three patients had prolonged urinary leakage for a mean of 21 days. CONCLUSIONS: Laparoscopic partial nephrectomy offers many advantages, including surgery that is both nephron sparing and minimally invasive. A vascular clamp was indicated for patients with less-than-1-cm-thick renal parenchyma between the tumor mass and renal sinus or calices.

Adult↗
PubMed2004

Early experience of laparoscopic radical nephrectomy for T3b renal cell carcinoma.

We report our experience with laparoscopic radical nephrectomy for a 79-year-old man who had renal cell carcinoma (RCC) with a renal vein thrombus. For the transaction of the renal vein with the thrombus, we used an endoscopic gastrointestinal anastomosis stapler. The operating time was 4 h and blood loss was 400 mL. The patient could walk and drink on the first postoperative day. He recovered normal activity 30 days postoperatively. There were no intraoperative and postoperative complications. The present report demonstrates the feasibility of laparoscopic radical nephrectomy in patients with T3b RCC who suffer from tumor thrombus in the renal vein.

Aged↗