This report describes a method of preparing samples of phosphodiesterase suitable for some chemical studies of desoxyribonucleic acid. A study of the use of purified phosphodiesterase in hydrolyzing thymonucleic acid has already been made (1). The source of our phosphodiesterase (snake venoms) was suggested by the work of Gulland and Jackson (2), although it now seems to us that their conclusio...

There are 4 genera of venomous snakes in Latin America: Bothrops, Crotalus, Lachesis, and Micrurus. Acute kidney injury (AKI) has been reported consistently after Bothrops and Crotalus envenomations. In fact, these 2 genera of snakes are responsible, along with the Russell's viper, for the majority of cases of snakebite-induced AKI reported worldwide. Although the Bothrops snakes are the leadin...

BACKGROUND Serine proteases are a major component of viper venoms and are thought to disrupt several distinct elements of the blood coagulation system of envenomed victims. A detailed understanding of the functions of these enzymes is important both for acquiring a fuller understanding of the pathology of envenoming and because these venom proteins have shown potential in treating blood coagula...

The initial step in the activation of Factor X by a tissue factor-Factor VII complex has been shown to involve hydrolysis of the same peptide bond as is hydrolyzed by Russell’s viper venom. The product, designated a-X&, undergoes autocatalytic conversion to a lower molecular weight form of equal coagulant activity, P-X,. The rate of this conversion is markedly enhanced by phospholipid which is ...

The mechanisms by which antivenom neutralizes the venom are still poorly understood. In the present work, we studied the effects of antivenom, constituted with either F(ab')2 or Fab, on the processes of absorption and elimination of Vipera aspis venom in experimentally envenomed rabbits. We first concluded from this study that during the few hours after intramuscular injection, the venom rapidl...

Sir,?Almost 40 years ago Calmette (1908) noted that lesions resulting from the injection of viper venom ' Strangely resembled those _ observed in the case of individuals who have died from yellow fever'. Calmette further remarks that this observation was made by several scientists, notably Sanarelli. and that it had probably led Dyer and Bettincour 'to treat?? without much success?yellow fever ...

as a powerful local haemostatic agent in the treatment of haemophilia. Fullerton (1940) substituted Russell's viper venom for rabbit-brain thromboplastin in his modification of Quick's one-stage prothrombin time, since viper venom could be obtained in a more convenient and more stable form than brain extract It soon became apparent, however, that the two methods gave widely different results. W...

experiments upon animals. The greater part of the book deals with the physiological action of venoms, proving the practically identical character of the poison of both colubrine and viperine snakes, though the local action of the latter is shown to be more pronounced. This corresponds with clinical experience, the bite of a viper causing intense pain, with extravasation and swelling, going on t...

Salivary gland extracts of the deerfly contain a potent inhibitor of platelet aggregation, which assists the insect in obtaining a blood meal. The extract prevents platelet aggregation induced by ADP, thrombin, and collagen and inhibits fibrinogen binding to the glycoprotein IIb/IIIa receptor on platelets. The active component in deerfly salivary gland extract appears to be a protein that is co...