Effects of acute methionine loading and vitamin C on endogenous fibrinolysis, endothelium-dependent vasomotion and platelet aggregation.

We assessed forearm blood flow and plasma fibrinolytic factors in eight healthy males who received unilateral brachial artery infusions of the endothelium-dependent vasodilator, substance P, and the endothelium-independent vasodilator, sodium nitroprusside. These measurements, together with platelet aggregation studies, were performed on four occasions after double-blind randomized ingestion of placebo, methionine (0.1 mg/kg), vitamin C (2 g) and methionine plus vitamin C. Blood flow and platelet aggregation responses were unaffected by methionine loading. Substance P caused dose-dependent increases in plasma tissue plasminogen activator (t-PA) antigen (from 3.0+/-0.1 to 4.7+/-0.4 ng/ml; P<0.001) and activity (from 1.2+/-0.2 to 4.2+/-0.4 i.u./ml; P<0.001), which were augmented during acute methionine loading (4.7+/-0.4 to 5.6+/-0.5 ng/ml and 4.2+/-0.4 to 5.5+/-0.9 i.u./ml respectively; P

Successful treatment of feline pyothorax associated with an Actinomyces species and Bacteroides melanogenicus.

A cat was presented to a veterinary clinic with a severe pleural effusion from which an organism later identified as an Actinomyces spp., probably A. odontolyticus, was isolated along with Bacteroides melanogenicus. It was successfully treated with surgical drainage and a combination of amoxycillin and sulphadiazine/trimethoprim. The fluid was cytologically examined to obtain a provisional diagnosis and to allow treatment to be initiated while the organisms were cultured and identified. The cat is now clinically normal except for slight abdominal respiration, presumably resulting from adhesions following the severe infection.