Gerald L. Brody

Immunosuppression with medroxyprogesterone acetate.

A potent synthetic progestin, medroxyprogesterone acetate (MPG), was evaluated for immunosuppressive activity. The survival of dogs with renal allografts was significantly prolonged and serum creatinine was decreased in animals treated with large doses of MPG. Survival of dogs with renal allografts which received both medroxyprogesterone and azathioprine was markedly prolonged when compared with animals receiving azathioprine alone. In rabbits receiving MPG alone, skin allografts survived 1.7 to 2.8 times longer than controls. The primary humoral antibody response of rabbits to bovine γ-globulin was also suppressed. The influence of MPG on peripheral leukocyte count and the histology of lymph nodes, spleen, and thymus was studied in clogs. Although probably not as potent an immunosuppressive agent, as azathioprine or corticosteroids, MPG may be useful in humans because of its low toxicity.

Monarticular juvenile rheumatoid arthritis

A child with recent onset of arthritis in a single joint often presents a diagnostic problem of considerable magnitude. The diagnosis of rheumatoid arthritis may be made with certainty only after specific diseases such as tuberculosis have been clinically eliminated; even then, correct therapeutic management of this form of arthritis is complex. This report reviews 40 patients who had monarticular rheumatoid arthritis in childhood and examines the diagnostic and prognostic aspects of the disease.

Cystic Lymphangiectasis of Bone

This report describes an unsusual case of deniinerahizimsg bone disease imm ann adolescemit boy. Comisiderable difficulty ss’as enicounstered mi estahhishimig a dingmsosis umitil msumerous biopsy specimemns w’ere obtaimned. Maniy diffuse amid sharply localized areas of skeletal densimserahization s’ere isoted mi the roenntgemsogramsss (Figs. 1, 2, and 3). The roentgenographic picture w’as furthen’ comifused h)y the presence of rachitic-hike chaiiges ins several of the epiphyseal limses (Fig. 1). The left lower extrensity was lomiger than the right, amid then’e was defimsite thickening of the skins and subcutaiseous tissue of the left calf, thigh, amid external gemsitahia.

Effect of Prolonged Hypoxia Upon Granularity of Renal Juxtaglomerular Cells

The various experimental models used in previous studies of the juxtaglomerular apparatus do not permit the effect of changes in oxygen tension of the renal parenchyma to be separated from that of changes in distension of the renal arterial bed. To study the isolated effect of prolonged hypoxia, three groups of rats, matched for weight, were kept in low oxygen, room air, and high oxygen environment for two weeks. The animals were pair-fed with the hypoxic rats serving as the determinant group. Supplemental injections of sodium chloride were given daily to avoid the effect of sodium deprivation on the juxtaglomerular cells. It was found that the hematocrits and also the granularity of the juxtaglomerular cells were significantly increased in the hypoxic rats as compared to the other two groups. Blood pressures, serum sodium levels, and urinary excretion of sodium were comparable among the three groups. These findings demonstrate that increased granularity of the renal juxtaglomerular cells can be induced by prolonged hypoxia.

Prolongation of skin homografts in rabbits, using cyclophosphamide

Summary 1. Cyclophosphamide can significantly prolong the survival of skin homografts in rabbits. 2. The histologic immune response in the regional lymph node and spleen was suppressed. 3. These results appeared to be a direct and specific effect of cyclophosphamide upon the immune mechanism, and not a nonspecific inhibition arising from a toxic state of the animals.

Effect of prolonged hypoxia upon the granularity of renal juxtaglomerular cells

The various experimental models used in previous studies of the juxtaglomerular apparatus do not permit the effect of changes in oxygen tension of the renal parenchyma to be separated from that of changes in distension of the renal arterial bed. To study the isolated effect of prolonged hypoxia, three groups of rats, matched for weight, were kept in low oxygen, room air, and high oxygen environment for two weeks. The animals were pair-fed with the hypoxic rats serving as the determinant group. Supplemental injections of sodium chloride were given daily to avoid the effect of sodium deprivation on the juxtaglomerular cells. It was found that the hematocrits and also the granularity of the juxtaglomerular cells were significantly increased in the hypoxic rats as compared to the other two groups. Blood pressures, serum sodium levels, and urinary excretion of sodium were comparable among the three groups. These findings demonstrate that increased granularity of the renal juxtaglomerular cells can be induced by prolonged hypoxia.

Transcholesterin titers and their biological significance in experimental atherogenesis in rats.

Summary The rise in titer of transcholesterin in the sera of rats on different high-fat or atherogenic diets was demonstrated. The reactive component is a serum alpha globulin which appears to combine specifically with cholesterol in agar gel immunoelectrophoresis. The serum cholesterol levels rise in various degrees in relation to diets but they do not correlate directly with transcholesterin titers. The observations suggest that transcholesterin functions as a homeostatic mechanism to meet the excess demands in disposal of cholesterol. The prompt rise of serum transcholesterin titer in rats on the high-fat diets and the moderate hypercholesterolemia may represent the adequacy of transcholesterin function in these animals. On an atherogenic diet, extreme heights of serum total cholesterol are reached early, again with mobilization of transcholesterin, after which the latter declines suggesting the homeostatic effort is approaching exhaustion or that the transcholesterin has been so fully combined that little remains free for further combining. The fall in total serum cholesterol after the peak of transcholesterin titers would be in keeping with the idea that this serum protein (or proteins) has a transport or clearing function for excessive cholesterol. The failure of cholesterol levels to be reduced to a normal range while transcholesterin titers decline is in accord with the concept of homeostatic failure. There was observed further the probable effect of aging upon total serum cholesterol accumulation in some animals on the control diet; this, too, was accompanied by moderate increase in serum transcholesterin titers.

Lipid Mobilizer Hormone in Triton Hyperlipemia.

Summary Tests were performed on baseline and periodic blood samples obtained from rabbits treated with intramuscular injections of Triton WR-1339. The ensuing hyper-lipemia was characterized by marked elevation in total fatty acids, triglycerides, cholesterol, lipid phosphorus, and total lipids. Paper electrophoresis revealed a concomitant increase in β-lipoproteins. Lipid mobilizer (LM) also increased strikingly, as was determined indirectly by testing plasma aliquots for inhibition of heparin activated clearing lipase. On the basis of these and related studies, is is suggested that Triton hyper-lipemia is produced, at least in part, through sustained release of increased amounts of LM which mobilize triglycerides to the portal circulation. Furthermore, Triton modifies metabolic activity of the liver so that post-hepatic hyperphospholipidemia and hypercholester-emia ensue.