Yutaka Kurita

Expression and functional role of β-adrenoceptors in the human urinary bladder urothelium

We investigated the presence of β-adrenoceptor subtypes in human urinary bladder urothelium and examined whether β-adrenoceptors in the urothelium modulate the relaxation responses of isolated human detrusor strips to a β-adrenoceptor agonist. Expression of β1-, β2-, and β3-adrenoceptor mRNA in urothelium and detrusor smooth muscle was determined by reverse transcription-polymerase chain reaction, and the distribution of β1-, β2-, and β3-adrenoceptors in human urinary bladder urothelium were examined by immunohistochemistry. Paired human longitudinal detrusor strips with and without an intact urothelium were suspended in organ baths to construct concentration-response curves to isoproterenol. The possible involvement of urothelium-derived nitric oxide (NO) in this response was examined in additional experiments with urothelium-intact strips in the presence of NG-nitro-L-arginine methylester (L-NAME). Results confirmed the expression of β1-, β2-, and β3-adrenoceptors in the human urinary bladder urothelium. Further, the presence of the urothelium caused a parallel rightward shift of the concentration-response curve to isoproterenol with a significant reduction in potency (pEC50). L-NAME failed to exert any significant effect on the relaxation response to isoproterenol in the urothelium-intact strips. These results confirm the presence of β1-, β2-, and β3-adrenoceptors in human urinary bladder urothelium. Further, they suggest that urothelial β-adrenoceptors induce the release of a urothelium-derived factor which inhibits the β-adrenoceptor agonist-induced relaxation of the human detrusor smooth muscle and that this inhibitory mechanism might not involve NO.

Increased Circulating Levels of Natriuretic Peptides Predict Future Cardiac Event in Patients with Chronic Hemodialysis

Background/Aim: Cardiovascular events are the major determinant of the prognosis in patients with chronic hemodialysis. The present study was designed to investigate whether increased plasma levels of atrial or brain natriuretic peptides (ANP or BNP) predict future cardiac events in such patients. Methods: Fifty-three patients undergoing chronic hemodialysis without clinical symptoms suggestive of cardiac disorders were enrolled and their blood was sampled for ANP and BNP measurements. Electrocardiograms demonstrated left ventricular hypertrophy in 28 patients but no other abnormal findings. We followed them up for 11.3 ± 0.2 months. The endpoint was cardiac events. Results: Cardiac events occurred in 13 patients (CE group). Both ANP and BNP levels were higher in CE group than in patients without cardiac events (ANP: 118 ± 21 vs. 56 ± 5 pg/ml, BNP: 769 ± 204 vs. 193 ± 25 pg/ml, respectively). Receiver operating characteristics curve revealed that the cut-off levels of ANP and BNP were 58 and 390 pg/ml, respectively. Using the Kaplan-Meier method, the incidence of cardiac events was significantly greater in patients with higher levels of ANP (50.0 vs. 0.0%) or BNP (72.7 vs. 11.9%) than in those with lower levels of the peptides. Conclusion: Elevated levels of ANP or BNP indicate an increased risk of cardiac events and these peptides are clinically useful to predict cardiac events in patients with hemodialysis.

Transition Zone Index as a Risk Factor for Acute Urinary Retention in Benign Prostatic Hyperplasia

OBJECTIVES To examine the efficacy of various parameters obtained by transrectal ultrasonography (TRUS) as predictors of the onset of acute urinary retention in patients with benign prostatic hyperplasia (BPH). METHODS From April 1993 to March 1997, 331 men aged 51 to 84 years with symptoms of BPH were enrolled in this study. Among them, 64 patients presented to our clinic because of acute urinary retention. TRUS was used to calculate the transition zone (TZ) volume, the transition zone index (TZ index = TZ volume/total prostate volume), the total prostate volume, and presumed circle area ratio (PCAR). To compare the usefulness of the various indices, the area under the receiver-operator characteristic (ROC) curve was calculated for each index. RESULTS There were significant differences in the American Urological Association (AUA) symptom score, total prostate volume, TZ volume, TZ index, and PCAR between patients with and without acute urinary retention, but no significant differences in age and quality of life score. In patients with acute urinary retention, the area under the ROC curve was 0.924 for the TZ index, 0.834 for the TZ volume, 0.753 for the PCAR, 0.684 for the total prostate volume, and 0.628 for the AUA symptom score. CONCLUSIONS The TZ index is an accurate predictor of acute urinary retention in patients with BPH and may be a useful method for deciding between surgical intervention and antiandrogen treatment.

Significant Prognostic Factors for 5‐Year Survival after Curative Resection of Renal Cell Carcinoma

Background: Renal cell carcinoma (RCC) patients occasionally die of RCC even after curative resection. In this study, we investigated prognostic factors between survivors for more than 5 years and patients who died within 5 years after curative resection.

Role of Doppler ultrasound and resistive index in benign prostatic hypertrophy

Background: The aim of the present study was to assess the resistive index in patients with benign prostatic hypertrophy (BPH) and the role of power Doppler ultrasonography.

Prognostic Factors for Renal Cell Carcinoma: A Multivariate Analysis of 320 Cases

Background We performed a multivariate analysis of clinical variables in 320 patients with renal cell carcinoma to identify important prognostic factors for long‐term survival.

PSA Value Adjusted for the Transition Zone Volume in the Diagnosis of Prostate Cancer

Background: The aim of the present study was to improve the accuracy of the prostate‐specific antigen (PSA) density for detecting prostate cancer by using the transition zone (TZ) volume instead of the total prostate volume.

Laparoscopic Nephrectomy for Atrophic Kidney Associated with Ectopic Ureter in a Child

An atrophic right kidney located in the pelvic cavity associated with an ectopic ureter was completely removed from a 4-year-old girl by laparoscopic surgery. There were no serious complications during the operation or the postoperative period. The light shining from the tip of a fine fiberscope inserted into the ureter was used to delineate this structure during laparoscopic surgery.

Resistive Index: A Newly Identified Predictor of Outcome of Transurethral Prostatectomy in Patients With Benign Prostatic Hyperplasia

OBJECTIVE To examine the usefulness of several preoperative parameters obtained through transrectal ultrasonography in predicting the outcome of transurethral resection of the prostate (TURP). METHODS A total of 572 men aged 51-85 years scheduled to undergo TURP for benign prostatic hyperplasia were prospectively enrolled, and 560 were ultimately evaluated. We preoperatively assessed International Prostate Symptom Score (IPSS), quality of life (QOL) score, maximum urinary flow rate (Q(max)), and postvoid residual urine volume (PVR), and measured total prostate volume (TPV), transition zone (TZ) index, and resistive index (RI) using transrectal ultrasonography. To compare the usefulness of the latter 3 indices, we calculated the area under the receiver operating characteristic (ROC) curve for each index and for IPSS. RESULTS IPSS (total, postmicturition symptoms, storage symptoms, voiding symptoms), QOL score, Q(max), and PVR were significantly improved after TURP. Significant differences between the effective and noneffective groups were observed with regard to age, IPSS (total, postmicturition symptoms, storage symptoms, voiding symptoms), QOL score, TPV, TZ index, RI, Q(max), and PVR. The area under the ROC curve was 0.663 for IPSS, 0.691 for TPV, 0.719 for the TZ index, and 0.845 for the RI. CONCLUSIONS The RI is a useful predictor of an effective outcome after TURP in patients with benign prostatic hyperplasia and may be useful for determining suitability for surgical intervention.

Resistance index in benign prostatic hyperplasia using power doppler imaging and clinical outcomes after transurethral vaporization of the prostate

Abstract  Background:  Using power Doppler ultrasonography (PDUS), we investigate the change of resistance index (RI) before and after transurethral vaporization of the prostate (TUVP) in benign prostatic hyperplasia (BPH) patients.