Hours In Normal Subjects Research Articles

Ultraviolet Radiation and Psoriasis

The macroscopic and microscopic reactions of nonpsoriatic and clinically uninvolved psoriatic skin to ultraviolet radiation (UVR) showed no gross differences. The erythema threshold was decreased in subjects whose psoriasis was in an acute, eruptive stage. On the basis of studies of epidermal DNA synthesis, ultraviolet radiation resulted in an injury response at 48 hours in normal subjects and in psoriatic patients in whom the disease was in an acute, eruptive stage. The injury response to UVR was significantly decreased in those subjects with chronic, nonerutive psoriasis and the reason for this is unexplained.

Neural, hematologic and bacteriologic effects of nitrofurantoin in renal insufficiency

Eleven subjects with normal kidney function and six with renal insufficiency were given nitrofurantoin, 100 mg orally; urine concentrations of the drug sufficient to inhibit growth of sensitive microorganisms were obtained during the next six hours in normal subjects but not in those with azotemia. Despite decreased excretion, the serum drug concentration did not increase in patients with renal failure. In nine uremic patients with urinary tract infection treated with nitrofurantoin, control peripheral nerve and/or sensory nerve conduction velocities were at the lower limits of normal in all but one. After nitrofurantoin at a lower dose as recommended by the manufacturer had been given, three had a minimal further decrease in conduction velocities, three others did not. In the three affected patients, normal conduction velocities were regained within two weeks of discontinuation of therapy. Serum ascorbate and folate concentrations were not influenced by treatment nor did their control values discriminate patients who had altered nerve function. Blood counts and erythrocyte methemoglobin reduction did not vary significantly during this study. Our findings suggest that when renal function is seriously compromised, nitrofurantoin can be used in reduced dosage without affecting peripheral nerve function, but effective antimicrobial levels in the urine cannot be achieved. On the other hand, if dosage is raised to attain effective antimicrobial levels, neurologic side effects may be anticipated.

Experience with a simple procedure for the determination of plasma and urine free 11-hydroxycorticosteroids

Plasma and urine free 11-hydroxycorticosteroids were measured by a simple fluorometric procedure. Precision and recovery of cortisol were excellent. The 8 to 9 a.m. mean plasma 11-hydroxycorticosteroid value was 17 ± 4.9 (S.D.) μg. 100 ml. and agrees well with those reported using the Porter-Silber chromogen technic for measurements of plasma nonconjugated corticosteroids in normal subjects. Dexamethasone 2 mg. every 6 hours for 24 hours resulted in plasma levels of 2.2 to 4.9 μg. 100 ml. ACTH 25 mg. I.V. over a 6 hour period in normal subjects gave a mean plasma value of 58.8 ± 10.9 (S.D.) μg. 100 ml. The mean plasma half-life of injected cortisol of 127 minutes is in good agreement with the values reported using other technics to measure cortisol. The mean urinary free 11-hydroxycorticosteroid excretion was 86.8 ± 29.5 (S.D.) μg. 24 hours in normal subjects. Dexamethasone suppression did not lower this below the normal range. The day of the ACTH infusion the mean urinary value rose to 895 ± 323 (S.D.) μg. 24 hours with only one value less than 470 μg. 24 hours . The technic applied to the plasma appears to offer a simple and rapid measurement of adrenal function that is adequate for most clinical purposes. Further studies are necessary to judge the urinary findings.

Comparative Utilization of Intravenous Fructose and Invert Sugar

Summary 1.Total 24-hour urinary losses of sugar were studied following inf usion of 10 per cent fructose and of 10 per cent invert sugar at rates of 1000 ml. per hour and 1000 ml. per 2.5 hours in normal subjects on alternate days, each patient thus serving as his own control. The average losses were 3.8 per cent to 7.1 per cent of the total amount infused, with a maximum of 11.4 per cent in any single patient. 2.The average amount of sugar excreted in the urine is less at the slowerrate of infusion with both sugars. 3.At each infusion rate, less sugar is excreted with fructose than with invertsugar, and the difference is largely due to the larger loss of glucose in the urine following infusion of invert sugar. Fructose given at a rate of 1000 ml. per 2.5 hours was most efficiently retained. 4.The results of this study suggest that 10 per cent invert sugar is notutilized as if the 5 per cent fructose and 5 per cent glucose components were treated independently by the body, but rather that the urinary sugar losses lie between those anticipated with 10 per cent fructose alone and 10 per cent glucose alone. There is certainly no suggestion of a favorable effect of one sugar on the other and retention of fructose is even less than would be expected had it been given alone. 5.Fructose and invert sugar infused into patients with widespread cancerbehave much as they do in normal subjects, although losses are somewhat greater, particularly at more rapid infusion rates. However, losses of glucose far in excess of those seen in normal patients after infusions of fructose were observed in 2 cases, suggesting abnormal conversion of fructose to glucose. 6.After major operations, infusions of both fructose and invert sugar areefficiently retained, just as in the case of normal patients. One patient excreted an unusual amount of glucose in the urine after infusions of fructose. 7.Postoperative urinary losses of sodium and potassium are of the ordernoted in previous studies with glucose infusion or with no infusion. Average losses of sodium were slightly higher with fructose than with invert, but in neither case is the loss exceptional (56.9 mEq. and 39.8 mEq.).