Blood Lines: Intraspecific and Interspecific Variations in Anticoagulant Actions of Viperid Venoms.

This study investigated the intraspecific and interspecific variability in the venom effects of viperid snake species and subspecies (eleven venoms total) on plasma clotting times, fibrinogen levels, and fibrin clot strength. Significant delays in plasma clotting time were observed for , , , , , and . Notably, the phylogenetically disjunct lineages , , and exhibited the most potent anticoagulant effects, indicating the independent amplification of a basal trait.

A Genus-Wide Bioactivity Analysis of (Viperinae: Viperidae) Viper Venoms Reveals Widespread Variation in Haemotoxic Properties.

The snake genus (Viperidae: Viperinae; Oppel, 1811) contains five species: , , and , found in Afro-Arabia, and the Russell's vipers and , found in Asia. Russell's vipers are responsible for a major proportion of the medically important snakebites that occur in the regions they inhabit, and their venoms are notorious for their coagulopathic effects. While widely documented, the extent of venom variation within the Russell's vipers is poorly characterised, as is the venom activity of other species within the genus.

Extensive Variation in the Activities of and Viper Venoms Suggests Divergent Envenoming Strategies Are Used for Prey Capture.

Snakes of the genera and (Viperidae: Viperinae) are known as the desert vipers due to their association with the arid environments of the Middle East. These species have received limited research attention and little is known about their venom or ecology. In this study, a comprehensive analysis of desert viper venoms was conducted by visualising the venom proteomes via gel electrophoresis and assessing the crude venoms for their cytotoxic, haemotoxic, and neurotoxic properties.

Differential coagulotoxicity of metalloprotease isoforms from Bothrops neuwiedi snake venom and consequent variations in antivenom efficacy.

Bothrops (lance-head pit vipers) venoms are rich in weaponised metalloprotease enzymes (SVMP). These toxic enzymes are structurally diverse and functionally versatile. Potent coagulotoxicity is particularly important for prey capture (via stroke-induction) and relevant to human clinical cases (due to consumption of clotting factors including the critical depletion of fibrinogen).

A Web of Coagulotoxicity: Failure of Antivenom to Neutralize the Destructive (Non-Clotting) Fibrinogenolytic Activity of and Spider Venoms.

Envenomations are complex medical emergencies that can have a range of symptoms and sequelae. The only specific, scientifically-validated treatment for envenomation is antivenom administration, which is designed to alleviate venom effects. A paucity of efficacy testing exists for numerous antivenoms worldwide, and understanding venom effects and venom potency can help identify antivenom improvement options.

Basal but divergent: Clinical implications of differential coagulotoxicity in a clade of Asian vipers.

Envenomations by Asian pitvipers can induce multiple clinical complications resulting from coagulopathic and neuropathic effects. While intense research has been undertaken for some species, functional coagulopathic effects have been neglected. As these species' venoms affect the blood coagulation cascade we investigated their effects upon the human clotting cascade using venoms of species from the Azemiops, Calloselasma, Deinagkistrodon and Hypnale genera.

Coagulotoxicity of (Lancehead Pit-Vipers) Venoms from Brazil: Differential Biochemistry and Antivenom Efficacy Resulting from Prey-Driven Venom Variation.

Lancehead pit-vipers ( genus) are an extremely diverse and medically important group responsible for the greatest number of snakebite envenomations and deaths in South America. (common lancehead), responsible for majority of snakebites and related deaths within the Brazilian Amazon, is a highly adaptable and widely distributed species, whose venom variability has been related to several factors, including geographical distribution and habitat type. This study examined venoms from four populations (Belterra and Santarém, PA; Pres.

Does size matter? Venom proteomic and functional comparison between night adder species (Viperidae: Causus) with short and long venom glands.

Night adders (Causus species within the Viperidae family) are amphibian specialists and a common source of snakebite in Africa. Some species are unique in that they have the longest venom glands of any viper, extending approximately 10% of the body length. Despite their potential medical importance and evolutionary novelty, their venom has received almost no research attention.

Factor X activating Atractaspis snake venoms and the relative coagulotoxicity neutralising efficacy of African antivenoms.

Atractaspis snake species are enigmatic in their natural history, and venom effects are correspondingly poorly described. Clinical reports are scarce but bites have been described as causing severe hypertension, profound local tissue damage leading to amputation, and deaths are on record. Clinical descriptions have largely concentrated upon tissue effects, and research efforts have focused upon the blood-pressure affecting sarafotoxins.