Approaches to prevention of asbestos-induced lung disease using polyethylene glycol (PEG)-conjugated catalase

Asbestos-associated damage to cells of the respiratory tract in vitro can be prevented by the simultaneous addition of scavengers of active oxygen species to cultures. To determine if administration of scavenger enzymes to animals and humans is a plausible approach to the prevention of asbestos-induced lung disease, osmotic pumps were filled with various concentrations of PEG-coupled catalase and implanted subcutaneously into Fischer 344 rats over a 28-day period. At 3, 14, and 28 days after implantation of the pumps, the animals were evaluated for levels of catalase in serum and lung. In addition, lung tissue and lavage fluids were examined at 28 days for biochemical and morphologic indications of cell injury, inflammation, and fibrotic lung disease. At all time points examined, the administration of PEG-catalase caused a dosage-dependent increase in serum levels of catalase. The levels of lung catalase were evaluated at 28 days but not at earlier time periods. In comparison to control rats, the amounts of enzymes (lactic dehydrogenase, alkaline phosphatase), protein, and cells in lavage fluids from treated animals were unaltered. Moreover, the lungs showed no evidence of inflammation or fibrotic disease as determined by differential cell counts in lavage and measurement of hydroxyproline. These studies suggest that administration of PEG-catalase does not cause injury or other alterations in lung tissue and can be pursued as a feasible approach to prevention of asbestosis.

Empirical assessment of identity in anorexia and bulimia nervosa

Researchers have neglected the study of the self concept of individuals who develop anorexia and bulimia nervosa. Towards rectifying this situation, Identity Structure Analysis (ISA) is introduced as an appropriate framework allowing the specification and empirical testing of postulates regarding disturbed identity development in anorexic disorders. The data presented distinguish a common constellation of identity characteristics in those suffering from anorexia and bulimia nervosa that differentiate them from normal and psychiatric control groups. Their identity pattern tends to be anti-developmental and in a state of 'identity crisis', in which identification conflicts with the maternal metaperspective of self (me as my mother sees me) are especially significant. Further analysis suggest that anorexics are in a phase of 'plummeting' identity crisis, whilst the patients in the sample with bulimia nervosa are in a 'sustained' phase. Future directions for research are noted.

Hip dislocation in cerebral palsy: selection for treatment

Forty-five patients with cerebral palsy hip-dislocation were reviewed and it was found that some did well without treatment. For patients with hip pain, the best results were obtained with extensive resection arthroplasty: soft-tissue surgery alone was unsuccessful. Open reduction with femoral osteotomy achieved concentric reduction in all 15 patients who had this type of surgery: however, most retained their abnormal postural reflex activity to such a degree that subsequent scoliosis, pelvic obliquity, hip extension contractures and knee flexion deformities compromised the success of the hip surgery.

Lysergic acid diethylamide: evidence for stimulation of pituitary dopamine receptors

Lysergic acid diethylamide (LSD), 0.05 mg/kg and 0.20 mg/kg, significantly decreased plasma prolactin (PRL) levels in male rats. LSD, 0.20 mg/kg, also inhibits the increase in plasma PRL levels produced by chlorpromazine (CPZ), 5 mg/kg, and alpha-methyl-paratyrosine (AMPT), 50 mg/kg, both of which interfere with dopaminergic inhibition of PRL secretion. LSD was more potent than methysergide, a serotonin receptor blocker, in lowering plasma PRL levels and more potent than apomorphine, a known direct acting dopamine agonist, in blocking the increase in plasma PRL produced by quipazine, a 5-HT agonist. These results suggest LSD has potent dopamine agonist properties on the rat pituitary or hypothalamic dopamine receptors which directly or indirectly inhibit PRL secretion.

Differential uptake of tritiated digoxin in benign and malignant central nervous system neoplasms

The purpose of this study was to measure uptake of tritiated digoxin by neoplastic tissues known to have differential contents of sodium-potassium adenosine triphosphatase (Na + K + ATPase), the presumed receptor for digoxin. Tumor samples were removed at the time of craniotomy in seven patients with meningiomas (Group 1) and seven patients with more malignant central nervous system tumors (Group 2) (three astrocytomas, three glioblastomas, one meduloblastoma). Patients with meningiomas were found to have a significantly higher digoxin uptake (21.8 +/- 7.3 ng/gm tumor versus 5.7 +/- 5.2 ng/gm tumor; (p less than 0.01) and a significantly greater tissue/serum ratio (13.9 +/- 11.7 versus 3.26 +/- 3.7, p less than 0.0). This study provides the first demonstration of increased uptake of digoxin by noncardiac pathologic tissues. The results are most likely due to differences in the number of digoxin receptor sites.

Repression of the overproduction of porphyrin precursors in acute intermittent porphyria by intravenous infusions of hematin

In a patient with a severe attack of acute intermittent porphyria, hematin given intravenously caused marked diminution of serum delta-aminolevulinic acid and porphobilinogen. The decline of aminolevulinate was more rapid than that of porphobilinoge. After 2 days of hematin administration, about 5 days were required for delta-aminolevulinic acid, and 11 days for porphobilinogen to return to the concentrations that were detected before treatment. Urinary excretion of both compounds also decreased after hematin administration. Considerable amounts of porphobilinogen were also found in the cerebrospinal fluid of the patient.

Distribution of Radioactivity in Milk Resulting from Oral Administration of 14C—Labeled Carbarl

Carbonyl-1 'C-labeled carbaryl administered orally to a lactating cow at a dose of 3.05 mg/kg resulted in the appearance of radiolabeled materials in milk. About 1% of the administered dose of 14C was recovered in the whole milk with a maximum concentration of 2.6 ppm carbaryl equivalents found in 9 hr. Radiometric assay of the milk fat showed a maximum level of 4.1 ppm carbaryl equivalents. Analysis of the skim milk by thin layer chromatographic assay failed to show the presence of carbaryl