Late ureteral obstruction and hematuria from de novo angiosarcoma in a renal transplant patient

A patient is described with a long-term functioning renal allograft who presented with ureteral obstruction and hematuria from an angiosarcoma. The diagnosis of ureteral obstruction was established preoperatively with computerized tomography guided anterograde pyelography. This represents the first documented case of an angiosarcoma occurring de novo in a renal allograft recipient. Continued awareness is needed of the increased risk of malignancy following transplantation.

Pyeloureteritis cystica

A case of pyeloureteritis cystica is presented. The incidental findings of an episode of hypertension focused attention on the urinary system. Urologic evaluation concluded a suspicious renal mass. The diagnosis was established only after histologic studies of the surgical specimen.

Re-evaluation of the relationship between the positive inotropic effect of ouabain and its inhibitory effect on (Na+ + K+)-dependent adenosine triphosphatase in rabbit and dog hearts

Previous studies have shown that in the ouabain-exposed rabbit heart, although positive inotropy and inhibition of (Na+ + K+)-dependent adenosine triphosphatase are induced concomitantly, the extent of inhibition of the enzyme remains constant when positive inotropy is washed out; and in the dog heart, if positive inotropy without arrhythmias is induced by ouabain, inhibition of the enzyme is not detected. The purpose of this work was the re-evaluation of these previous findings. Rapid recovery of the enzyme from small tissue samples was achieved by homogenization in 1 M KCl and centrifugation. When the enzyme was prepared by this method from ouabain-exposed rabbit and dog hearts, ouabain remained bound to the enzyme. The extent of inhibition of the enzyme was measured by the fluorimetric assay of K+-dependent 3-O-methylfluorescein phosphatase before and after removal of bound ouabain. Correlation between the extent of inhibition of this activity and that of (Na+ + K+)-dependent adenosine triphosphatase activity was established. Utilizing these refined methods, the following results were obtained. In the rabbit heart, positive inotropy and enzyme inhibition occurred concomitantly. Washout of the effect resulted in partial reactivation of the enzyme. In the dog heart, the previous findings were confirmed. The results are not inconsistent with the hypothesis that enzyme inhibition is the cause of the positive inotropic effects. They do suggest, however, the need for further testing of the hypothesis.

Prepubertal gonorrhea

Two cases of gonococcal urethritis in male children are presented and the records of 45 other children with gonorrhea are reviewed. The presentation, diagnosis and treatment are discussed. Data on the mode of transmission are presented with emphasis on the high incidence of gonorrhea in family members or close contacts of infected children, or a history of sexual abuse.

Localized scleroderma with cutaneous calcinosis. A distinctive variant

Two patients had a distinctive variant of localized scleroderma. Both have a history of sclerodermatous changes of the skin over the face developing relatively late in life and accompanied by hair loss, cutaneous calcification, and prominent beaking of the nose. A striking lack of systemic involvement also was noted.

(Na+ + K+)-ATPase: effects of detergents on the cross-linking of subunits in the presence of Cu2+ and o-phenanthroline

When (Na+ + K+)-ATPase is reacted with Cu2+ or Cu2+-phenanthroline, cross-linking of the two subunits (alpha and beta) occurs. The major products are alpha,beta- and alpha,alpha-dimers. The alpha,beta-dimer is unstable in the presence of EDTA, but becomes stable when it is first exposed to digitonin or Triton X-100. Conversion of alpha-CU2+-beta to alpha-S-S-beta is suggested. If the enzyme that is pretreated with these detergents is used, only the stable alpha,beta-dimer is obtained, and the formation of alpha,alpha-dimer is inhibited. The data are consistent with alpha 2 beta 2 quaternary structure of the enzyme.

Urinary zinc, copper, nitrogen, and potassium losses in response to trauma

The urinary losses of zinc, copper, nitrogen and potassium were measured for 14 trauma patients for periods ranging from nine to 30 days and for nine normal subjects over four days each. The mean losses per day as well as peak losses by patients were compared to the mean normal losses. The mean peak losses of all elements were 2 to 10 times greater than normal. The ratios of the urinary concentrations of these catabolites in relation to each other were calculated. Since nutritional support was predominantly by routine intravenous solutions, the large amounts of urinary zinc, copper, nitrogen and potassium excreted represent a severe drain on the body's reserves of these elements.

Steroid myopathy in connective tissue disease

In eight women with polymyositis (three patients), systemic lupus erythematosus (SLE) (three patients), rheumatoid arthritis (one patient) and shoulder-hand syndrome (one patient), weakness developed during high dose prednisone therapy. These women were studied using serial functional and manual muscle tests, determination of serum glutamic oxaloacetic transminase (SGOT), creatine phosphokinase (CPK) and serum aldolase levels, and urinary excretion of creatine. Insidious onset of weakness was characteristic. Myalgias were seen in five patients and unusual sudden weakness in two. Weakness was always most severe in the pelvic girdle muscles; there was a lesser involvement of shoulder girdle and distal muscles. Serum muscle enzyme levels were normal in all cases, but urinary creatine excretion was invariably increased and proved to be the most sensitive laboratory indicator for clinical diagnosis and for monitoring patient improvement. Serial urinary creatine excretion and serum enzyme studies were of value in differenting steroid myopathy from a flare of myositis in patients with connective tissue disease. Diagnosis and effective management were achieved by the use of readily available laboratory and clinical procedures without resorting to muscle biopsy.

Studies on the mechanism of inhibition of the red cell metabolism by cardiac glycosides

The purpose of this work was to test the previously suggested hypothesis that the inhibitory effect of ouabain on lactate production in human red cells is due to an interaction between phosphoglycerate kinase and (Na+ + k+)-activated adenosine triphosphatase (Na+,K+ATPase). An antibody to red cell phosphoglycerate kingase caused complete inhibition of the purified enzyme, whereas a portion of the phophoglycerate kinase activity of the red cell membranes was resistant to the antibody. When increasing amounts of the purified enzyme were added to the membranes, the antibody-resistant portion of the activity increased. The effects of the antibody and ouabain on lactate production from fructose-6,6-diphosphate in red cell hemolysates were studied. Ouabain, at a maximally effective concentration, produced about 30% inhibition of lactate formation. This value was doubled in the presence of the antibody. Red cell membranes, and rat brain Na+,K+-ATPase, did not catalyze the hydrolysis of 1,3-diphosphoglycerate. Ouabain did not affect the reactions of the Rapport-Luebering pathway of the red cells. These findings provide further support for the view that in red cells a membrane pool of phosphoglycerate kinase is oriented in the vicinity of Na+,K+-ATPase in a way that the product of each enzyme may be used as the immediate substrate of the other and that ouabain inhibits glycolysis by removing the regulatory effect of Na+,K+-ATPase on that portion of glycolysis which is channeled through this pool of phosphoglycerate kinase.

Uptake of some quaternary ammonium ions by human erythrocytes

In many biophysical studies on erythrocytes some quaternary ammonium ions are used as replacements for Na⁺ and K⁺ of the physiological solutions. The object of this work was to study the possible uptake of quaternary ammonium ions by erythrocytes. Uptake of C¹⁴–choline chloride and C¹⁴–tetramethylammonium chloride by human erythrocytes was proved. It was shown that the compounds were neither incorporated into phospholipids of the cell nor converted to any other metabolites. Studies of uptake as a function of time, at several external concentrations of choline and tetramethylammonium, showed that within the first 4 hours uptake was a linear function of time regardless of the external concentration of the quaternary ammonium ions. The effects of various external concentrations of choline and tetramethylammonium ions on the rate of uptake by the cells were studied. The results showed the presence of two distinct mechanisms for the uptake of choline: one, a facilitated uptake mechanism which becomes saturated at low external concentrations of the ion; the other, a simple diffusion mechanism in which the rate of uptake is proportional to concentration. For the facilitated part of the uptake the external choline concentration at which half-maximum rate was obtained was found to be 0.02 mm. Although the kinetic studies with tetramethylammonium ion were not as extensive as those with choline, they did suggest the presence of similar mechanisms for the uptake of both ions. Tetramethylammonium and tetraethylammonium ions were shown to be competitive inhibitors of the facilitated choline uptake.