Investigative urology最新文献

In isolated human urethra, prazosin competitively inhibited contractions induced by noradrenaline, but had no effect on contractions elicited by potassium (127 mM), suggesting an action solely on alpha-adrenoceptors. Seven patients with lower motor neuron lesions and micturition disturbances were treated with 2 mg of prazosin twice daily. Five were investigated by simultaneous urethrocystometry before and during treatment. Prazosin reduced the intraurethral pressure, the intravesical pressure during bladder filling, and autonomous bladder waves. Voiding and incontinence improved in five patients. In one, voiding was facilitated, but continence deteriorated, and in one, no clinical effects were observed. In all patients, residual urine decreased. There were no side effects, except one case of nasal congestion. It is concluded that prazosin effectively reduces alpha-adrenoceptor mediated hyperactivity in the smooth muscle of the lower urinary tract, and that it may be an effective treatment of micturition disturbances in patients with lower motor neuron lesions.

Peripheral blood leukocytes were cultured from patients with renal cell carcinoma and compared with those from normal volunteers. The number of macrophage precursor cells recovered was 17.99 +/- 11.65 X 10(3) cells per ml of blood in patients with renal cell carcinoma, whereas the number recovered in normal individuals was 72.0 +/- 20.0 X 10(3) cells per ml of blood. The low macrophage yield in patients with renal cell carcinoma was not associated with serum factors, and there was no difference in the number of monocytes in the mononuclear cell preparations. Therefore, there seems to be an intrinsic defect in the macrophage maturation process in vitro in patients with renal cell carcinoma.

The radiosensitizing properties of misonidazole (Ro-07-0582; NSC-26137) were evaluated in a leg transplanted model of N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) induced transitional cell bladder carcinoma in C3H/He mice. Animals bearing tumor received fractionated radiation of 400 rads X 5 or 600 rads X 5. Other groups with the same radiation doses were treated with misonidazole (0.75 mg per g) before each radiation fraction. Radiation alone was effective in prolonging Mean Survival Time, 17 per cent for 400 rads X 5 and 45 per cent for 600 X 5, with an associated delay in tumor growth. Misonidazole in the 600 rads X 5 group showed a radiosensitizing effect by further slowing tumor growth and prolonging Mean Survival Time by 80 per cent over the control and 24 per cent over radiation alone. Misonidazole alone did not show notable cytotoxic effects.

Two fistulae were created in each of 26 adult male New Zealand rabbits. In six, no closure was carried out. In 20 rabbits subsequent closure was carried out using, alternately, a macroscopic and microscopic technique. We were then able to evaluate a total of 26 repaired fistulae using several parameters. Patency of the fistulae was present after 3 months in all six rabbits in which no closure was carried out. Comparison of the two techniques showed nine recurrences or persistent fistulae in the ten repaired by standard macroscopic techniques, and one fistulae still present after closure of 16 fistulae using microsurgical principles. This preliminary study emphasizes the potential improvement in urethral fistula repair using the operating microscope. Direct transfer into the clinical setting is underway with the use of techniques used in the Microsurgical Laboratory at the University of British Columbia.

We employed an experimental hyperoxaluric protocol involving the administration of 1 per cent ethylene glycol drinking water to rats to determine (i) the location and mechanism of retention of renal tubular calcium oxalate crystals, and (ii) how this tubular deposition is modified by magnesium deficiency and contributes to stone formation. Calcium oxalate monohydrate deposition was found predominantly within the lumina of proximal tubules, and was markedly accelerated by magnesium deficiency. Sheet- and strandlike mucoid appearing material attached the crystals to the luminal surface of the renal tubules. The structure of stones found in the renal pelvis suggested that tubular deposits aggregate to form the nidus of the calculus.

Electron and light microscopic observations were made on experimentally induced cystitis in rats with particular emphasis on the role of polymorphs in the wall of the urinary bladder. Polymorphs appear from the time of invasion of bacteria to the epithelial cells of the bladder, aggregate primarily around infected epithelial cells, which become surrounded and isolated from healthy epithelial cells, and accelerate the desquamation of the infected epithelial cells. In the submucosal layer, all invading bacteria are phagocytized by polymorphs. Although polymorphs found in the intercellular space of the epithelial cells do not show phagocytosis, those that are released into the lumen of the urinary bladder do.

From 21 dogs kidneys removed at 0, 1, 2, and 4 weeks after ureteral blockage we found the expected early increase, than subsequent decrease, in pressure and the expected continuing increase in volume and thinning of the walls. However the calculated wall stress builds up continuously with time as does the elastic modulus of the wall. By the 4th week, the wall material has become approximately 3 times as resistant to stretch as the normal ureter.

The blood testis barrier has been implicated in the pathogenesis of testicular relapse of childhood acute leukemia by forming a "sanctuary site" for leukemic cells. Experiments were conducted to test the transport of carbon 14 cyclophosphamide and tritiated vincristine across the blood testis barrier. Both cyclophosphamide and vincristine crossed the blood testis barrier. However, other factors such as the transport of immunoglobins and leukocytes across the blood testis barrier may interact in the pathogenesis of leukemic testicular relapse.

We developed a surgical model in the cat, in which the bladder was completely separated from the urethra, in order to examine the changes in urethral resistance during bladder filling. An increase in urethral resistance occurred in two phases: an "initial" increase attributable to the activity of both the striated sphincter and the sympathetically innervated smooth muscle, and a "late" increase that is alpha-sympathetically mediated. The latter was secondary to trigonal distension. We concluded that the increased urethral activity during bladder filling is reflexly mediated and that the trigone plays a role in its control.