Influence of paradoxical sleep deprivation and sleep recovery on testosterone level in rats of different ages.

This study was performed to assess serum testosterone alterations induced by paradoxical sleep deprivation (PSD) and to verify their attenuation during sleep recovery (SR) based on different durations and ages. Wistar male rats aged 12 weeks for the younger group and 20 weeks for the elder group were randomly distributed into one of the following groups: a control group (cage and platform), 3-day SD, 5-day SD, 7-day SD, 1-day SR, 3-day SR and 5-day SR groups. For PSD, the modified multiple platform method was used to specifically limit rapid eye movement (REM) sleep. Differences in the testosterone and luteinizing hormone levels between the younger group and the elder group according to duration of PSD and SR recovery were analysed. Testosterone continued to fall during the sleep deprivation period in a time-dependent manner in both the younger (P=0.001, correlation coefficient r=-0.651) and elder groups (P=0.001, correlation coefficient r=-0.840). The elder group showed a significantly lower level of testosterone compared with the younger group after PSD. Upon SR after 3 days of PSD, the testosterone level continued to rise for 5 days after sleep recovery in the younger group (P=0.013), whereas testosterone concentrations failed to recover until day 5 in the elder group. PSD caused a more detrimental effect on serum testosterone in the elder group compared to the younger group with respect to decreases in luteinizing hormone (LH) levels. The replenishment of serum testosterone level was prohibited in the elder group suggesting that the effects of SD/SR may be age-dependent. The mechanism by which SD affects serum testosterone and how age may modify the process are still unclear.

Magnetic resonance urethrography to assess obliterative posterior urethral stricture: comparison to conventional retrograde urethrography with voiding cystourethrography.

PURPOSE: We prospectively evaluated magnetic resonance urethrography for depicting obliterative posterior urethral stricture. MATERIALS AND METHODS: A total of 25 men with a mean age of 48.7 years (range 21 to 72) with complete posterior urethral stricture were studied preoperatively with axial and sagittal turbo spin-echo T2, sagittal T1 and contrast enhanced sagittal T1-weighted images. Of the 25 patients 22 underwent conventional retrograde urethrography with voiding cystourethrography. For magnetic resonance urethrography aseptic lubricant was infused through the external urethral meatus to dilate the distal urethra up to the stricture. Each imaging result was compared with a surgical specimen or a description of the surgical findings. Measurement errors were analyzed using the Wilcoxon signed rank test. The relationship between true and measured stricture length was evaluated by linear regression analysis. RESULTS: Based on magnetic resonance urethrography findings 2 patients with a less than 1 cm stricture were treated with internal urethrotomy, 21 with a more than 1 cm stricture underwent open urethroplasty and 2 with prostatic displacement and a 4 cm stricture needed the combined perineal and transpubic approach. The mean +/- SD measurement error on magnetic resonance urethrography imaging was significantly lower than that on conventional retrograde urethrography combined with voiding cystourethrography (0.4 +/- 0.4 vs 1.4 +/- 1.1 cm, p <0.001). Linear regression analysis showed a stronger linear relationship between magnetic resonance urethrography and surgical measurement (r(2) = 0.62, p <0.01). CONCLUSIONS: Magnetic resonance urethrography is more effective for evaluating obliterative posterior urethral stricture than retrograde urethrography combined with voiding cystourethrography.

The role of vesicoureteral reflux in acute renal cortical scintigraphic lesion and ultimate scar formation.

PURPOSE: We assessed whether differences exist in the rates of acute photon defect and scar formation using dimercapto-succinic acid scintigraphy according to the presence and grade of vesicoureteral reflux. MATERIALS AND METHODS: A total of 389 patients with a first febrile urinary tract infection were enrolled. For all patients ultrasonography, dimercapto-succinic acid scintigraphy and voiding cystourethrography were performed. Dimercapto-succinic acid scintigraphy was performed within 5 days of and 6 months after diagnosis of urinary tract infection. Voiding cystourethrography was performed after the acute phase of urinary tract infection. The rates of acute photon defect and scar formation on dimercapto-succinic acid scintigraphy according to the presence and grade of vesicoureteral reflux were assessed. RESULTS: A total of 125 females and 264 males were included in the study. Of the patients 93 had refluxing urinary tract infection and 296 had nonrefluxing infection. The rate of acute photon defect (74.2% vs 32.1%, p = 0.0001) and the rate of ultimate scar change on followup dimercapto-succinic acid scintigraphy were significantly higher in patients with refluxing urinary tract infection (50% vs 18.3%, p = 0.0001). Positive linear association was noted between reflux grade and acute photon defect by linear association test (p = 0.002). No association was found between reflux grade and scar formation (p = 0.262). CONCLUSIONS: Although vesicoureteral reflux is not a prerequisite for development of acute photon defect and subsequent renal scarring, reflux itself might be an aggravating factor for acute photon defect and scar formation. There seems to be a correlation between reflux grade and frequency of acute photon defect on dimercapto-succinic acid scintigraphy but scar change occurs independently of reflux grade.

Practical management of nocturia in urology.

Until last decades, nocturia has been considered as an irritative symptom of benign prostatic hyperplasia (BPH), but the nocturia is unresponsive symptoms to various modalities of BPH treatment. More recently, it has been recognized that the prostate is not so quite important as previously believed, as nocturia is equally common in women. The understanding of nocturia has been much changed in last decade; it is a highly prevalent condition, and symptoms in men and women are really no different either quantitatively or qualitatively. The successful introduction of desmopressin (l-deamino-8-D-arginine vasopressin, DDAVP) to decrease nocturnal urine output in severe nocturia which resistant to conventional BPH treatment and in women demonstrated new perspectives in management of nocturia. We reviewed the definition and etiologies of nocturia, offering the current diagnostic procedures and standards of care.

Antidiuretic hormone in elderly male patients with severe nocturia: a circadian study.

OBJECTIVE: To investigate the circadian variation of plasma antidiuretic hormone (ADH) and urine output in patients with severe nocturia (> three times per night) and to assess the effect of oral desmopressin on nocturnal urine output in these patients. PATIENTS AND METHODS: Twelve patients with severe nocturia and five age-matched controls without were assessed over 24 h (circadian sampling) during a 72-h hospital admission. Blood levels of ADH and changes of urine output were measured in the patients before and after the oral administration of desmopressin (0.2 mg, at 22.00 hours in the second day), and in the controls not treated with desmopressin. RESULTS: Compared with the normal control, the patients had no diurnal variation in urine output and greater nocturnal urine production, associated with a lack of nocturnal increase in ADH level. Compared with the baseline urine output, desmopressin significantly decreased night-time (23.00-08.00 hour) urine output in the patients (P < 0.05). Desmopressin significantly increased the osmolality of night-time urine (P < 0.05), and there was no systemic adverse reaction. CONCLUSIONS: Severe nocturia in a large proportion of elderly men with lower urinary tract symptoms is caused by nocturnal polyuria and natriuresis, because they have no nocturnal increase in ADH. These results suggest that desmopressin may be effective in decreasing nocturnal urine production in patients with severe nocturia who do not respond to conventional treatment.