Envenoming by Echis saw-scaled viper is the leading cause of death and morbidity in Africa due to snake bite. Despite its medical importance, there have been few investigations into the toxin composition of the venom of this viper. Here, we report the cloning of cDNA sequences encoding four groups or isoforms of the haemostasis-disruptive Serine protease proteins (SPs) from the venom glands of ...

Platelet aggregation inhibitory effect and anticoagulant properties of fractions separated from the venoms of Cerastes persicus fieldi and Echis carinatus were investigated. The partial fractionation was performed on a Sephadex G-100 column. Two fractions separated from Cerastes persicus fieldi showed anti platelet aggregation activity on ADP (200 μM)-induced platelet aggregation (ca 80% inhibi...

A reptile holder based in the Czech Republic was bitten into his hand and foot by the Northeast saw-scaled viper (Echis pyramidum). The person arrived at the health institution after twenty hours for anuria. Despite the antivenom against the Asian Echis carinatum - the Echis pyramidum's close relative - was readily available and administered repea...

The processes that drive the evolution of snake venom variability, particularly the role of diet, have been a topic of intense recent research interest. Here, we test whether extensive variation in venom composition in the medically important viper genus Echis is associated with shifts in diet. Examination of stomach and hindgut contents revealed extreme variation between the major clades of Ec...

Envenoming by Echis ocellatus is potentially life-threatening due to severe hemorrhage, renal failure and capillary leakage. These effects are attributed snake venom metalloproteinases (SVMPs). ...

It is shown that Echis carinatus venom activates both coagulation factor II and coagulation factor X. The activation of both proenzymes by the venom is Ca++-dependent; phospholipids are not necessary. The activation of factor II by the venom is a slow process and, in the absence of factor X, the clotting activity towards fibrinogen is generated only very slowly. Because Echis carinatus venom cl...

H EMORRHAGE is the outstanding phenomenon observed following the bite by snakes of the Viperidae and Crotalidae families. Subjects bitten by these snakes show local hemorrhage near the site of the bite, slowly extending proximally, and, after death, widespread hemorrhage in many internal organs. In the explanation of the hemorrhage, two mechanisms have been invoked; damage to the vessel wall ca...

H EMORRHAGE is the outstanding phenomenon observed following the bite by snakes of the Viperidae and Crotalidae families. Subjects bitten by these snakes show local hemorrhage near the site of the bite, slowly extending proximally, and, after death, widespread hemorrhage in many internal organs. In the explanation of the hemorrhage, two mechanisms have been invoked; damage to the vessel wall ca...

The composition of snake venoms shows a high degree of variation at all taxonomic levels, and natural selection for diet has been implicated as a potential cause. Saw-scaled vipers (Echis) provide a good model for studying this phenomenon. The venoms of arthropod feeding species of Echis are significantly more toxic to natural scorpion prey than those of species which feed predominantly upon ve...