Retinal surgery complicated by a spontaneously acquired factor VIII inhibitor

We studied a factor VIII inhibitor spontaneously occurring in an otherwise healthy patient who underwent retinal reattachment. The clotting defect first manifested itself as a delayed hemorrhagic choroidal detachment. His bleeding diathesis was successfully managed by infusion of factor VIII concentrate, prednisone, and cyclophosphamide. Surgical procedures in patients with severe bleeding disorders present a difficult therapeutic problem which can be effectively managed by the close cooperation of the surgeon, hematologist, coagulation laboratory, and blood bank.

Metabolic properties of maintained oligodendroglia purified from brain

Oligodendroglia isolated in bulk from dissected white matter of lamb or calf brain can now be maintained in culture for several days. The cells remain intact and viable during this time. The in vitro incorporation of various radiolabeled precursors into lipids or proteins was examined, and its was found that oligodendroglia synthesize the lipids which are predominant in brain, and especially in myelin. They actively synthesize cholesterol, cerebrosides, sulfatides, and all of the phospholipids, especially phosphatidylcholine. In addition, they produce a variety of radiolabeled proteins, with those of high molecular weight exhibiting the most radioactivity. Thus the cells are metabolically very active in vitro and can be used as a model system to study turnover of lipids in the cell, as well as the synthesis of myelin-specific components.

Phosphorylation of proteoglycans in human articular cartilage

A study of human articular cartilage indicated that componenet proteoglycans can be phosphorylated. Phosphorylation, also found in a specimen of human epiphysial cartilage, occurred when [gamma-32P]-ATP or 32Pi was included in the in vitro incubation medium. Treatment of the phosphorylated proteoglycans with chondroitinase and chondrosulfatases effectively removed the chondroitin sulfate without dephosphorylating the remaining molecule. Since phosphorylation could be effected in a totally chemically defined medium, it appears that the necessary enzyme systems for this reaction are contained entirely within chondrocytes.

Ultrastructure of the lung in the rat following exposure to crocidolite asbestos and quartz

Lung tissue from rats that had inhaled U.I.C.C. crocidolite asbestos or quartz particles showed thickening of the interstitial tissue and the presence of collagen fibres. Aggregates of macrophages in the alveolar spaces were a dominant feature of all the sections examined from asbestos exposed rats. According to the ultrastructural studies described here, all the macrophages were mature cells, indicating that the ingested crocidolite asbestos was non-toxic. Lung sections of rats exposed to quartz particles were significantly different. Single cells were found in the alveolar spaces and many macrophages showed a characteristic pattern of vacuole formation. Other cells contained intracellular membranous lamellated bodies, similar to those found in Type II pneumocytes. Cells containing lamellated bodies were also found in the interstitial tissue. These findings suggest that the two mineral dusts have quite different biological effects on the macrophage and that the development of pulmonary fibrosis may, to some extent, be caused by a different mechanism in each instance.

Calcium and cancer

For many years the calcium ion has repeatedly cropped up in research work concerning the transformation of the normal cell to the malignant state. When these results are collected together they indicate that calcium may hold the key to the solution of many of the problems concerning the cancer cell.

The in vivo effects of quartz on rat thoracic lymph nodes

The histological changes in the regional thoracic lymph nodes of rats exposed to silica dust by inhalation are recorded. A dual response is noted involving both inflammatory and immune mechanisms, resulting in a fibroblastic connective tissue reaction and a plasma-cell-macrophage interaction. It is proposed that the progressive silicotic lesions obstruct the lymphatic channels in the lymph nodes, thus interfering with the lymph drainage from the lung and aggravating the silicotic process in the lung itself.

Immune adherence reactivity of rat alveolar macrophages following inhalation of crocidolite asbestos

The immune adherence phenomenon was used to demonstrate the in vivo deposition of complement on membranes of alveolar macrophages from rats chronically exposed to crocidolite asbestos dust. Pre-treatment of macrophage cualtures with anti-C3 antiserum greatly diminished the level of immune adherence reactivity. Alveolar macrophages exposed to crocidolite asbestos in vitro did not exhibit significant levels of immune adherence reactivity. These results may reflect an in-vivo antigen-antibody-complement interaction on the surface of a alveolar macrophages from animals which have inhaled asbestos dust.

Breakdown products of C3 and factor B in hemolytic-uremic syndrome

Serum concentrations of Clq, C4, C3, and Factor B but not properdin were significantly decreased in patients with HUS compared to values in normal control subjects (p value less than 0.01). Sera from 13 HUS patients obtained early after the onset of the disease showed breakdown products of Factor B (Ba, Bb) by immunoelectrophoresis; 12 of these sera showed C3 breakdown products (C3c, C3d). Sera from seven patients studied 1 month to 3 years later no longer demonstrated any breakdown products of Factor B or C3. These data suggest that the complemented system is activate in HUS. The concept that immunological mechanisms play a major role in this disease is additionally supported by the occurrence of IgM, C3, and fibrin in glomeruli and renal vessels.

Fetal metachromatic leukodystrophy: pathology, biochemistry and a study of in vitro enzyme replacement in CNS tissue

Brain tissue from a fetus with the diagnosis of metachromatic leukodystrophy (MLD) became available at autopsy. Pathologic studies of the CNS showed inclusion bodies within oligodendroglia. The morphology of myelin was normal. Cells and myelin were isolated from the cerebrum; there was an increased level of sulfatide present in both fractions. In vitro studies of enzyme replacement in cultured MLD brain cells indicated that it may be possible to correct the abnormal sulfatide accumulation.

Immunopathology of renal extracellular membranes in diabetes mellitus. Specificity of tubular basement-membrane immunofluorescence

This study documents the presence of marked immunofluorescence for IgG and albumin in renal extracellular membranes, especially tubular basement membranes (TBM), of patients with severe diabetic nephropathy. A comprehensive immunofluorescent analysis was carried out on kidney tissue from 83 patients--Group I: 24 living normal renal allograft donors and two infants less than one week of age. Group II: 24 patients with severe nephropathy who had juvenile onset of diabetes 16 to 30 years previously and who ranged in age from 20 to 47 years. Group III: 33 patients with severe kidney disease of varied etiologies with an age range of five to 63 years. The sections were assayed for a variety of proteins (immunoglobulins, complement components, and tissue antigens). Kidney sections of all patients with severe diabetic nephropathy were readily distinguished from kidneys of other patients and normals by the intense linear staining of the extracellular membranes, especially the tubular basement membrane for IgG and and albumin. Dual-labeled studies using FITC anti-basement membrane (BM) and tetramethyl rhodamine (TMR) antialbumin demonstrated localization of the albumin predominantly to the outer but also the inner TBM while the BM antisera reacted more intensely with the inner membrane. There is no evidence that an immunologic process is responsible for these findings. These immunofluorescent findings are specific for severe diabetic nephropathy and may reflect structural changes in the renal extracellular membranes that permit entrapment of serum proteins, possibly due to changes in permeability.

Immunopathology of renal extracellular membranes in kidneys transplanted into patients with diabetes mellitus

Kidneys of patients with severe diabetic nephropathy demonstrate marked linear immunofluorescent staining of extracellular membranes, including the tubular and glomerular basement membranes (TBM and GBM) and Bowman's capsule. Immunofluorescent studies were carried out on kidney tissue obtained from 12 diabetic and 17 nondiabetic patients from two to 12 years following renal transplantation. The frequency and intensity of SgG and albumin staining of these membranes were significantly greater in the diabetic than in the nondiabetic patients (P less than 0.0005). TBM, GBM, and Bowman's capsule staining did not occur in any of the seven kidneys studies at the time of their transplantation into diabetic recipients. Thus, the abnormalities leading to the deposition or trapping of proteins in renal extracellular membranes occur early after the placement of normal kidneys into the abnormal metabolic environment of the diabetic transplant recipient. The present study supports the concept that basement membrane alterations in diabetes are a consequence of the biochemical perturbations of diabetes rather than a separately inherited genetically linked disorder.

Immunopathology of the end-stage kidney. Immunoglobulin and complement component deposition in nonimmune disease

Seventy nephrectomy specimens from patients with end-stage renal disease, four renal biopsies from patients with focal sclerosing glomerulonephropathy (FSGN) and normal renal function, and 17 control biopsies from normal renal allograft donors (Group I) were studied by immunofluorescence with respect to deposition of immunoglobulins and classic and alternative complement (C) pathway components. The end-stage kidneys were divided into three groups according to etiology: 16 patients with immune-mediated glomerulonephritis (Group II), 22 patients with congenital and/or familial renal disease (Group III), and 32 patients with systemic or primary renal disease in which an immune-mediated injury could not be established (Group IV). The pattern of immunoprotein deposition in glomeruli in Groups II, III, and IV, and in biopsies of patients with FSGN was similar: peripheral lobular, globular and/or granular, focal and segmental; it was limited to dying glomeruli or abnormal glomerular segments. A statistically significant correlation existed between the percent of properdin-containing glomeruli and the percent of glomeruli undergoing hyalinization in Groups II, III and IV (II, r=0.67; III, r=0.92; IV, r=0.78). No deposition was observed in normal or completely fibrotic glomeruli. In vitro heterologous complement fixation was demonstrated in 17/19 end-stage kidneys in a similar distribution. Early classic C components, C1q and C4, were detected in a somewhat higher frequency in Group II (14/16) than Group III (11/22) and Group IV (20/32) (Group II vs. III, P=.02 and II vs. IV, P=.07). C3 and properdin were detected in 77 to 100% of all 3 groups; in 18 patients, C3 and properdin were present without detectable C1q and C4. Immunoglobulins, primarily IgM, and components of the classic and alternative C pathways are regularly present in hyalinizing glomeruli irrespective of the etiology of the renal failure. These observations suggest that an immune process is operative in glomerular obsolescence regardless of the underlying etiology of the renal disease.

The immunology of asbestosis

Forty-one employees with varying degrees of asbestosis have been tested for any alteration in the immunological profile. Of these, twenty-two employees showed evidence of pleural thickening and nineteen parenchymal asbestotic fibrosis. Those employees showing pleural thickening gave a strong reaction to different skin tests and a few of those with a parenchymal asbestotic fibrosis showed depressed cutaneous reactivity. Lymphocytotoxic antibodies were present in the sera of 60% of those with pleural thickening and 94% of those with parenchymal asbestosis. An immunological screening schedule is suggested for those employees who show pleural thickening.

Metabolism and temperature regulation in young harbor seals Phoca vitulina richardi

Metabolism and the ability to regulate core and peripheral temperatures under a variety of ambient conditions were studied in five unrestrained pups (less than 5 wk old) and four 3- to 5-mo-old harbor seals. Pups born with nonlanugo (adultlike) hair and little fat were able to swim in 5 degrees C water for several hours without becoming hypothermic. They were also found to tolerate 5 degrees C air temperature with the fur wet and exposed to a 35-knot wind. Basal metabolism in pups averaged 0.8 ml O2 g-1 h-1, which is 2.6 times the predicted value for an adult mammal of the same weight. Lower critical temperature in air was about 3 degrees C. Oxygen uptake in 3- to 5-mo-old seals under basal conditions was 0.5 ml g-1 h-1. Minimal thermal conductance values were .02 and .015 ml O2 g-1 h-1 degrees C-1 in pumps and 3- to 5-month-old seals, respectively. Appendages, and to a lesser extent the skin on the torso, cooled appreciably at lower air temperatures, and the flippers were kept just above freezing in subzero air. Tissue insulation provided by low peripheral temperatures and a high resting metabolic rate enable newborn and developing harbor seals to tolerate the low temperatures encountered in their natural environment.

A developmental complex including supravalvular stenosis of the aorta and pulmonary trunk

A developmental complex is described characterized by (1) supravalvular stenosis of the aorta and pulmonary trunk, (2) dysplasia of valves and (3) stenosis of ostia of coronary arteries and branches of the aortic arch. From the four cases described, it is evident that not all of the features of the complex need be present in a given case and, when present, some lesions are not of functional significance. The variations underly the potential for differences in the hemodynamic states of affected subjects.

Galactokinase: evidence for a new racial polymorphism

Activities of galactokinase and galactose-1-phosphate uridyltransferase in red cells were assayed in a mixed racial population of 645 pregnant women. The distribution of individual transferase activities for black subjects was the same as that for whites. In contrast, the distributions of individual galactokinase activities differed significantly in blacks and whites, the mean for the black population being 30 percent lower than the mean for the white population. The same racial difference was found when red cell galactokinase activity was examined in males and in newborns. Because low-, intermediate-, and high-galactokinase activities appear to segregate within several black families, this observed difference suggests a new, racially determined enzyme polymorphism.

Metabolic response to oral glucose in healthy South African white, Indian, and African subjects

The response of serum insulin, growth hormone, plasma free fatty acids, triglycerides, and blood glucose to an oral glucose load was investigated in healthy White, African, and Indian subjects. Serum cholesterol, uric acid, platelet adhesiveness, and urine insulin clearance were also measured. Each racial group responded differently. Most striking were the differences between Africans and Whites; despite similar mean blood glucose values at all times during the test, the Africans had lower serum insulin levels, a lower urine insulin clearance, a much greater rise of growth hormone, a more definite and prolonged suppression of free fatty acid release, lower serum cholesterol and uric acid levels, and a trend towards lower plasma triglyceride values.The Indians tended to resemble Whites rather than Africans with respect to their insulin, growth hormone, cholesterol, and triglyceride levels. Their glucose tolerance was decreased compared with that of the other two groups, but suppression of their free fatty acids was enhanced. Platelet adhesiveness was similar in all three groups.The reasons for these differences are unknown, but must be related to genetic and environmental differences among the three races.