Aplastic anemia in association with gold therapy for rheumatoid arthritis

Over a ten year period five patients developed aplastic anemia in association with gold therapy for rheumatoid arthritis. None of these patients was suitable for bone marrow transplantation due to the lack of a compatible sibling. Four patients with severe aplastic anemia died, despite intensive haemopoietic support and trials of gold chelating agents. Survival ranged from 22 to 103 days (mean 55 days) with death in each case being due to a combination of bleeding and infection. The remaining patient with moderate aplasia survived, recovering over a period of two to three years.

Import of proteins into mitochondria. The precursor of cytochrome c1 is processed in two steps, one of them heme-dependent

The apoprotein of yeast cytochrome c1 is made outside the mitochondria as a larger precursor which is then processed in at least two steps. In the first step, it is transported across both mitochondrial membranes and converted by a matrix-localized protease to an intermediate form whose molecular weight is between that of the precursor and the mature form. The intermediate form is bound to the outer face of the inner membrane. This first step requires an energized mitochondrial inner membrane, but no heme. In the second step, the intermediate form is converted to the mature cytochrome. This second step requires heme; it is blocked in a heme-deficient mutant or in wild type cells treated with an inhibitor of heme synthesis. Import of cytochrome c1 into mitochondria thus proceeds via two distinct heme-free precursors and at least two maturation steps, one of them dependent on heme.

Interstitial deletion of chromosome 7: a case report and review of the literature

A de novo deletion 7q11 leads to q21.2 was identified in a newborn with genital and other minor clinical abnormalities and some degree of psychomotor retardation. A review of the literature revealed a number of cases of deletion 7q, which can be categorized into three groups according to their breakpoints. Attempts to correlate phenotype with genotype in these cases have been only moderately successful, and as yet only deletion 7q32 leads to qter can be associated with a definite clinical syndrome, although a tentative syndrome may be postulated in association with deletion of region 7q22 leads to 7q31.

Clobazam in catamenial epilepsy. A model for evaluating anticonvulsants

The cyclical exacerbations of epilepsy (catamenial epilepsy) were used to assess the antiepileptic effect of a benzodiazepine, clobazam. Doses of 20 mg, and in some cases 30 mg, per day were compared with placebo over predetermined ten-day periods in a double-blind cross-over study. The results were evaluated by preference in a sequential procedure. In 14 of 18 patients who received both treatments clobazam was superior to placebo, and in 4 patients no preference was established. Clobazam completely prevented seizures in most of the patients, and toxic effects were of low frequency and severity.

Imported mitochondrial proteins cytochrome b2 and cytochrome c1 are processed in two steps

Cytochrome b2 of yeast is located in the space between the inner and outer mitochondrial membranes whereas cytochrome c1 is bound to the outer face of the mitochondrial inner membrane. Both proteins are made outside the mitochondria as larger precursors that are processed to their mature forms in two steps. In the first step, at least a segment of the precursor polypeptide chain penetrates into the mitochondrial matrix and is cleaved to an intermediate form by a matrix-localized soluble protease. This step requires an electrochemical gradient across the mitochondrial inner membrane. In the second step, the intermediate form is converted to the mature form. For cytochrome c1, this second step requires heme. Import of these two cytochromes thus involves a "detour" across the inner membrane.

Proximal tubular necrosis associated with maleic acid administration to the rat

Administration of maleic acid to the rat is used as an experimental model of Fanconi's syndrome. To determine the site and extent of morphologic injury within the kidney after maleic acid administration, we systematically examined renal tissue using light, transmission electron, and scanning electron microscopy. Tissue was studied either immediately or 24 hours after rats received maleic acid, 200 mg. or 400 mg. per kg. of body weight, and was compared with tissue from controls. In kidneys of maleic acid-treated rats, evidence of injury was observed only in cells of the late pars convoluta and the pars recta in the medullary rays of the cortex and in the outer stripe of the medulla. Injured cells were characterized by an increase in cytoplasmic density, accumulation of numerous small vesicles in the apical region of the cells, abnormal-appearing mitochondria with compressed cristal membranes and flocculent densities, and focal loss of microvilli. Injury was apparent immediately after maleic acid administration and progressed to extensive necrosis by 24 hours after either the 200- or 400-mg. per kg. dose. Except for the presence of granular and hyaline casts in the lumena, the loops of Henle and distal convoluted tubules were normal. Collecting ducts in the outer medulla, but not in the cortex, medullary rays, or inner medulla, had significantly increased numbers of dark cells per total cell population when compared with controls (p less than 0.005). This increase in dark cells may represent an adaptive response of the medullary collecting duct to the functional abnormalities of maleic acid-induced Fanconi's syndrome. Collecting ducts showed no evidence of cell injury or necrosis. These observations provide evidence that maleic acid, like many other renal toxins, produces tubular injury and necrosis only in the proximal tubules, primarily in the medullary rays, and outer stripe of the medulla, and not in the distal tubules.

The use of rotating gratings for the treatment of amblyopia: a clinical trial

The use of rotating gratings for the treatment of amblyopia was subjected to a controlled clinical trial. A treatment group (N = 19) observed rotating gratings for 15 min per week for 10 weeks and a control group (N = 19) observed a blank rotating disk for the same period. Both groups of amblyopes performed visually guided tasks to maintain their interest during treatment. Data were acquired in a double-masked manner. A second control group (N = 4) underwent weekly acuity evaluation without any form of treatment. Visual acuity was evaluated before and after each session and analyzed with a linear regression fit to a probit transform by a minicomputer. By using a criterion change in acuity of 10% Snell Sterling, we found no significant change of acuity in any group or between groups. These results demonstrate that rotating gratings are an insignificant variable in the treatment of amblyopia.

Lipoprotein metabolism in nonresponders to increased dietary cholesterol

We have studied the effect of increased dietary cholesterol on production and degradation of plasma very low density lipoproteins and low density lipoproteins. We studied five unselected normal volunteers who were on weight-maintaining diets consisting of 45% carbohydrate, 40% fat, and 15% protein with a ratio of polyunsaturated to saturated fat of 0.4. Cholesterol content was 150 mg/1000 kcal in Period A and 500 mg/1000 kcal in Period B. Subjects were fed each diet for 4 to 5 weeks. The turnover of apoproteins B in very low density and low density lipoproteins and of triglyceride in very low density lipoproteins were measured during the last 2 weeks of each study period using 131I-labeled very low density lipoproteins and 125I-labeled low density lipoproteins and 2-3H-glycerol, respectively. There was no significant change in plasma total cholesterol or triglycerides or in low density lipoprotein cholesterol levels during the high cholesterol versus the low cholesterol diet. Similarly, high cholesterol intake had no effect on the rate of production or clearance of apo B in very low density and low density lipoproteins or of triglyceride in very low density lipoproteins. These data indicate that the flux of very low density lipoproteins does not change in nonresponders to high cholesterol diets.

Generalized van der Waals theory. VII. Interface profiles and surface tension

An equilibrium theory of fluids based on a simple free-energy density functional developed and tested in several preceding articles is here applied to estimate the shape and surface tension of a gas/liquid interface in a simple LJ(12-6) fluid. The calculation is carried out at several different levels of approximation. In the simplest case when a step function profile is assumed the surface tension is obtained analytically. It is too high by about 50%. By using a moment expansion of the nonlocal free energy functional, the surface tension can be reduced to a simple one-dimensional integral. The result is now only slightly high. Finally, a variational calculation assuming a tanh form for the profile has been carried out. The effect of nonlocal entropy is examined and found to cause a drop in the surface tension by 5-10%. The results for the surface tension and width of the profile are in good agreement with experiment and simulation (deviation c. 0%) when plotted against T/Tc.

1,2-Dichloropropane: metabolism and fate in the rat

1. The metabolism of 1,2-dichloropropane in the rat has been investigated. The major urinary metabolite has been isolated and identified as N-acetyl-S-(2-hydroxypropyl)cysteine. Two minor metabolites of 1,2-dichloropropane have been identified as beta-chlorolactate and N-acetyl-S-(2,3-dihydroxypropyl)cysteine. 2. The fate of 1-chloro-2-hydroxypropane, a proposed intermediate metabolite of 1,2-dichloropropane, has been investigated. Apart from its known urinary metabolite, N-acetyl-S-(2-hydroxypropyl)cysteine, two oxidative metabolites were detected. These were identified as beta-chlorolactaldehyde and beta-chlorolactate. 3. A pathway is proposed for the metabolism and fate of 1,2-dichloropropane in the rat. This accounts for previous observations made for the fate of radioactivity from administration of 1,2-dichloro[1-14C]propane. 4. The microbial and mammalian metabolism of several halogen-containing foreign compounds is discussed.

Appropriateness review: a planning function or a regulatory tool?

The appropriateness review process can be used as a planning function by hospitals; however, hospitals and their medical staffs should become involved in the process to ensure that it does not become a regulatory tool.

Enzyme-linked immunosorbent assay (ELISA): a study of antibodies to Mycobacterium tuberculosis in the IgG, IgA and IgM classes in tuberculosis, sarcoidosis and Crohn's disease

Enzyme-linked immunosorbent assay (ELISA) has been used to study the levels of antibody binding to the soluble antigens of Mycobacterium tuberculosis (BCG) in the IgG, IgM and IgA classes in sera from patients with tuberculosis, sarcoidosis and Crohn's disease. Of the patients with tuberculosis, 75% had significantly elevated levels of anti-M. tuberculosis antibodies in the IgG class. The levels of antibodies in the IgM and IgA classes were much less discriminative. Many of the patients with sarcoidosis and Crohn's disease had significantly elevated levels of antimycobacterial antibodies, principally in the IgM and IgA classes. These elevated levels of antibody were not related to the total levels of the immunoglobulin classes. For the purpose of serodiagnosis, an estimation of the antimycobacterial antibodies in the IgG class gives the most discriminative results.

The specificity of the humoral immune response to soluble mycobacterial antigens in tuberculosis

A high proportion of patient with tuberculosis have been shown to produce significant levels of antibodies to antigens unique to Mycobacterium tuberculosis, antigens restricted to the slowly growing mycobacteria and antigens common to all species in the genus. About 20% of patients with this disease do not have significantly elevated levels of antibodies to any of these groups of antigens. Consequently, the availability of highly purified soluble antigens specific for M. tuberculosis would not permit more cases of tuberculosis to be diagnosed serologically.