Effect of furosemide on renal excretion of oxypurinol and purine bases

To examine whether furosemide affects the plasma concentration and urinary excretion of purine bases and oxypurinol, we administered allopurinol (300 mg) orally to 6 healthy subjects and then administered furosemide (20 mg) intravenously 10 hours later. Furosemide (20 mg) decreased the urinary excretion of uric acid by 40% (P < .01), oxypurinol by 39% (P < .05), and xanthine by 43% (P < .05) and the fractional clearance of uric acid by 45% (P < .01) and oxypurinol by 34% (P < .05) when measured 1 to 2 hours after administration. Moreover, furosemide increased the plasma concentration of uric acid by 6% at 1.5 hours after administration. These results indicate that furosemide may decrease the urinary excretion of uric acid and oxypurinol by acting on their common renal transport pathway(s). In addition, it is suggested that the effect of furosemide on oxypurinol is clinically important, since the hypouricemic effect of allopurinol may become more potent as a result.     

Mantle cell lymphoma of the rectum at an early stage: a case report.

We report a very rare early-stage case of mantle cell lymphoma, which arose from the rectum. A 60-year-old man presented with a small elastically hard polypoid lesion in the rectum. The lesion was 1.2 x 1.2 cm in size. As a preoperatively barium enema and endoscopy suggested a benign tumor of the rectum, he underwent local excision of a rectal polypoid mass transanally under spinal anesthesia. However, histological examination revealed a malignant lymphoma, because the lesion was histologically characterized by solid growths of small to medium-sized round cells. Furthermore, immunohistochemical tests revealed B-cell marker positivity and CD5 positivity, but cyclin D1 negativity. Since it was reported that lymphomas with a mantle cell lymphoma morphology and CD5 expression, but without cyclin D1 overexpression, exist in about 10% of mantle cell lymphoma cases, we diagnosed his disease as mantle cell lymphoma. To our knowledge, this is the first reported case of an early-stage mantle cell lymphoma, originating from the rectum.     

Effects of a low dose of indapamide, a diuretic, given daily or every-other-day on blood pressure and metabolic parameters.

To investigate the effects of the diuretic, indapamide, on blood pressure (BP) and metabolic parameters, thirty hypertensive patients were treated with 1 mg of indapamide either every day or every other day. BP, fasting plasma glucose, lipids, serum potassium and uric acid were determined at baseline and after 3 months of a stable regimen of the drug. At the termination of the study, 48-h ambulatory blood pressure monitoring (ABPM) was performed. Three patients received only indapamide, while other patients were treated in combination with additional antihypertensive medications. Patients treated with daily indapamide showed a BP reduction from 162 +/- 2.9/85 +/- 2.4 mmHg to 134 +/- 2.4/71 +/-2.6 mmHg (p < 0.001). The BP reduction was similar in those patients receiving the drug every other day (137 +/- 3.4/71 +/- 3.6 mmHg). While plasma lipids and serum potassium did not differ significantly with the intervention, uric acid increased significantly with daily treatment and normalized with every-other-day treatment. Glycosylated hemoglobin A1c (HbA1c) was not altered (5.6 +/- 0.1% vs. 5.4 +/- 0.2%), and did not differ between patients with and without diabetes mellitus. ABPM revealed an average 24-h BP of 134 +/- 3.3/75 +/- 1.7 mmHg on days in which patients received the medication and 139 +/- 4.9/78 +/- 2.6 mmHg on the intervening day without indapamide (no significant difference). These results suggest that a low dose of indapamide given every day or every other day is effective in lowering BP and does not result in metabolic derangements.     

Induction of islet B-cell regeneration in partially pancreatectomized rats by poly(ADP-ribose) synthetase inhibitors

In order to clarify the mechanism of the prevention of diabetes mellitus developing after subtotal pancreatectomy, we examined regenerative activities of islet B-cells in 90% pancreatectomized and poly (ADP-ribose) synthetase inhibitor-treated rats by using autoradiographic and stathmokinetic techniques. Thirty days after 90% pancreatectomy, islets of rats without 3-aminobenzamide treatment were decreased in number, small in size and had irregular contour. Degranulation of the B-cells and fibrotic degeneration were frequently encountered. On the contrary, islets of remaining pancreas in rats receiving 3-aminobenzamide were increased in number, and their diameters ranged from 0.3-0.6 mm, being about two fold larger than those of normal rats. The labeling index of 3H-thymidine autoradiography and the mitotic indices in islet B-cells were increased in a temporally correlated manner in the 3-aminobenzamide treated rats. The mitotic indices of the 3-aminobenzamide-treated group on the 5th, 7th, 10th and 15th days were significantly larger than those in the control group. These results indicate that poly (ADP-ribose) synthetase inhibitors can induce self-replication or regeneration of B-cells in partially pancreatectomized rats.