Can carbon fiber implants substitute for collateral ligament?

The biomechanic and histologic changes following replacement of the medial collateral digit of the knee with carbon fiber filament prostheses of varying diameters were studied in young rabbits. Biomechanic testing showed changes with time in the mode of failure and force to failure of the replacements, but the initial differences in the force to failure of the three diameter groups diminished over the 12-week experimental period. Histologic studies with both light and electron microscopy revealed resorption of the carbon fibers and replacement by fibrosed ligaments. There was a correlation between the change in mode of failure and force to failure and increased production, orientation, and organization of new collagen fibrils, as well as simultaneous fragmentation of the carbon fibers.     

Action of Δ9-tetrahydrocannabinol on membrane-bound monoamine oxidase activity

In vivo administration (ip) of Δ⁹-tetrahydrocannabinol (Δ⁹-THC) to adult rats under acute conditions (10 and 50 mg/kg) produced a dose-dependent stimulation of monoamine oxidase (MAO; monoamine: O₂ oxidoreductase (deaminating), EC 1.4.3.4) activity in blood platelets and in mitochondrial preparations of hypothalamus and heart. Chronic treatment (10 mg/kg/day for 15 consecutive days) produced a smaller stimulating effect on MAO activity of these tissues. In vitro treatment with Δ⁹-THC produced (1) a stimulatory effect in hypothalamic MAO up to a concentration of 4 μg/mg of protein, (2) an inhibitory effect on heart MAO, and (3) a slight though not insignificant inhibitory effect on platelet MAO. Kinetic studies of in vivo and in vitroΔ⁹-THC-treated enzyme (MAO) are discussed on the basis of K_m and V_max values obtained from Linewwaver-Burk plots. When KSCN, KNO₃, and urea were used, they produced a significant inhibitory effect on MAO activity in all these tissues, even in the presence of Δ⁹-THC, indicating that a characteristic interaction between membrane-bound MAO and Δ⁹-THC can be disrupted by these chaotropic agents.     

A general hospital psychiatric unit inpatient facility

Summary Patients admitted to the inpatient ward of a psychiatric unit in a general hospital have been studied with regard to their clinical characteristics, reasons for admission and discharge patterns. The results indicate that patients are most often admitted for the management of acute disturbance and detailed diagnostic evaluation and they are discharged in a semi-improved state. Implications of such a service pattern are discussed.     

Urticaria in Children

Abstract: The etiologic factors responsible for urticaria were analyzed in 44 children seen In the Urticaria Clinic, a referral center of the Dermatology Department. Of these, 23 were girls and 21 boys. Nine (20.5%) had acute urticaria and 25 (79.5%) were diagnosed as having chronic urticaria. A definitive etiology factor was identified in 1B (40%) patients. Of these, 15 had physical urticarias; in 2 foods and in 1 drug was incriminated. Probable ettologlc factors were identified in 19 (43%) patients, in 5 (11.3%) of whom more than one factor was Identified. In 11 (25%) children, it was not possible to establish the cause. Our study suggests that etiologic factors of urticaria are more readily identifiable in children than in adults.     

Effects of emetine on the metabolism of ascorbic acid

Treatment with emetine lowered the ascorbic acid concentrations of serum, liver and kidney, while the ascorbic acid concentration of adrenal tissue remained unaffected. The ability of the liver to synthesize (-)-ascorbic acid from (+)-glucuronolactone was also reduced after emetine treatment. The reduced concentration of ascorbic acid in liver and serum after emetine treatment may result from the diminished synthesis of ascorbic acid by the liver.     

Changes in plasma urate concentration immediately after acute myocardial infarction.

The plasma urate concentration of 70 patients with acute myocardial infarction increased progressively up to the seventh day and was significantly higher than in a group of 23 patients with ischaemic changes only. Diuretic treatment might have accounted for an early rise in urate levels but the persistent increase seen at seven days could not be so explained.