Anti-edematous effects of tolvaptan in experimental rodent models.

PURPOSE: The aim of this study was to evaluate the therapeutic efficacy of tolvaptan, a vasopressin V(2) receptor antagonist, on edema in two rat models: 1) histamine-induced vascular hyperpermeability of the dorsal skin and 2) carrageenan-induced paw edema. METHODS: In the skin vascular hyperpermeability model, 3 h after oral administration of tolvaptan or the natriuretic agent furosemide, rats were intravenously injected with Evans Blue (EB), followed by intradermal injection of 10 µg of histamine into the dorsal skin. One hour later, blood was collected to measure serum parameters. EB leakage area into the dorsal skin was also measured. Urine was collected for 4 h to determine urine parameters. In the paw edema model, edema was induced by injecting 1% w/v carrageenan into the right hind paw. Paw volume was measured hourly for 5 h. Tolvaptan or furosemide was orally administered 1 h before carrageenan injection. RESULTS: A single oral dose of tolvaptan (1-10 mg/kg) elicited marked and dose-dependent aquaresis, and improvements in edema. Similar effects were observed with furosemide (30 mg/kg). Tolvaptan tended to elevate the serum sodium level while furosemide caused a significant decrease. CONCLUSION: Tolvaptan had anti-edematous effects in two different rat models. By increasing free water excretion, tolvaptan may be more advantageous for certain patients than loop diuretics because it does not cause electrolyte loss, and may prevent electrolyte abnormities, such as hyponatremia. These results suggest that tolvaptan has potential clinical benefits for the treatment of edema.

Simultaneous determination of Zn, Cd, Pb, and Cu in urine of patients with blackfoot disease using anodic stripping voltammetry.

Blackfoot disease (BFD) is an endemic peripheral vascular disorder resulting in gangrene of the lower extremities, especially the feet, among residents in a limited area on the southwest coast of Taiwan. In the present study, the concentrations of zinc, cadmium, lead, and copper in urine of BFD patients with matched normal controls are investigated by differential pulse anodic stripping voltammetry (DPASV) on a hanging mercury drop electrode (HMDE). The analytical results indicate that urinary copper, cadmium, and lead of the BFD patients are significantly higher than those of the controls. In addition, the patients showed a significantly lower concentration of zinc in the urine than the normal controls. The possible connection of these elements with the etiology of the disease is discussed.

Tophaceous gout of the foot: an unusual presentation of severe chronic gout in an undiagnosed patient.

Tophaceous deposits are frequently noted within articular cartilage, synovium, tendons, tendon sheaths, pinnae and the soft tissue on the extensor surface of the forearms, feet, and bursae in patients with a history of chronic gout. The authors describe an unusual case of severe chronic tophaceous gout without prior diagnostic history or presence of acute attacks. They describe the procedure for the excision of these masses as well as the radiographic and pathological findings.

Physician documentation of diabetes care: use of a diabetes flow sheet and patient education clinic.

We assessed two interventions designed to improve the care of patients with diabetes mellitus by documenting the complications of their disease. These were a flow sheet, included with outpatient medical records, and a weekly patient education clinic, in which a nurse educator provided individualized instruction to patients with diabetes. Physician compliance with recommendations of the National Diabetes Advisory Board for diabetes care was measured before (n = 45) and after (n = 158) these interventions. The numbers of referrals to ophthalmologists increased from 22% to 46%, urinalyses increased from 58% to 77%, and lower extremity examinations increased from 36% to 61%. Nutrition education documentation increased from 51% to 69%, and diabetes education documentation increased from 31% to 61%. These results suggest that a significant improvement in physicians' documentation of care of patients with diabetes can be achieved by using a flow sheet and a diabetes patient education clinic.

EGF receptor-binding activity in the urine of normal horses and horses affected by chronic laminitis.

A heterologous radioreceptor binding assay (RRA) has been developed capable of detecting nanogram amounts of epidermal growth factor (EGF) receptor-binding activity in equine urine. The binding parameters of [125I]mEGF (murine EGF) to EGF receptors on equine plasma membranes are in good agreement with values from other EGF-RRA systems. The dissociation constant estimated from equilibrium methods (KD = 4 X 10(-10) M) is in reasonable agreement with that determined from the rate constants (KD = 6 X 10(-10) M) and is in good agreement with values determined in other species. The assay is specific for equine EGF (eEGF) receptor-binding activity and capable of detecting less than 0.34 nM eEGF receptor-binding activity in urine. Equine EGF receptor-binding activity in equine urine form adult horses varied widely between samples (8.5 +/- 6.5 nM). This variability was somewhat reduced when values were adjusted for dilutional effects using urine creatinine as an indicator (3.6 +/- 2.0 nanomoles/g creatinine). No significant differences were demonstrated between the means of EGF binding activity concentrations in clinically normal horses and horses affected by chronic laminitis.

Clinical laboratory studies for the podiatric surgical patient.

Doctor Arden emphasizes the mimportance of the preoperative history and physical examination, including clinical laboratory studies, on all podiatric surgical patients. He discusses the complete blood count, coagulation studies, blood chemistry, serologic tests for syphilis, and urinalysis. These clinical studies may give evidence of undetected disease which could have a major impact on the surgery to be performed.