Topic
Echis
About: Echis is a research topic. Over the lifetime, 87 publications have been published within this topic receiving 1873 citations.
Papers published on a yearly basis
Papers
TL;DR: Examination of stomach and hindgut contents revealed extreme variation between the major clades of Echis in the proportion of arthropod prey consumed, providing strong evidence that variation in snake venom composition results from adaptive evolution driven by natural selection for different diets.
Abstract: 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 Echis in the proportion of arthropod prey consumed. The toxicity (median lethal dose, LD50) of representative Echis venoms to a natural scorpion prey species was found to be strongly associated with the degree of arthropod feeding. Mapping the results onto a novel Echis phylogeny generated from nuclear and mitochondrial sequence data revealed two independent instances of coevolution of venom toxicity and diet. Unlike venom LD50, the speed with which venoms incapacitated and killed scorpions was not associated with the degree of arthropod feeding. The prey-specific venom toxicity of arthropod-feeding Echis may thus be adaptive primarily by reducing venom expenditure. Overall, our results provide strong evidence that variation in snake venom composition results from adaptive evolution driven by natural selection for different diets, and underscores the need for a multi-faceted, integrative approach to the study of the causes of venom evolution.
358 citations
TL;DR: The phylogeny of the medically important and taxonomically unresolved viper genus Echis is analyzed using four mitochondrial gene fragments, showing that the populations of the genus fall into four main clades: the EChis carinatus, E. coloratus,E.
141 citations
TL;DR: Echis carinatus is the most important cause of morbidity and mortality from snake bite in Nigeria and in many other parts of the world, and patients with systemic poisoning by this snake were given echis antivenom made either by the South African Institute for Medical Research (S.A.M.I.R.R.) or by Behringwerke (North and West African polyvalent antivenoms).
Abstract: Echis carinatus is the most important cause of morbidity and mortality from snake bite in Nigeria and in many other parts of the world. Forty-six patients with systemic poisoning by this snake were given echis antivenom made either by the South African Institute for Medical Research (S.A.I.M.R.) or by Behringwerke (North and West African polyvalent antivenom). A simple test of blood coagulability was used to assess whether an adequate neutralizing dose of antivenom had been given. An average of 15·2 ml S.A.I.M.R. antivenom restored normal coagulability permanently in all 23 patients in one group, but in the other group receiving an average dose of 37·9 ml Behringwerke antivenom normal clotting resulted in only 18 out of 23 patients. Local tissue swelling was similar in both groups, but local necrosis occurred in three patients treated with Behringwerke antivenom and in none given S.A.I.M.R. antivenom.
109 citations
TL;DR: A new polyvalent anti-ophidian antivenom (Antivipmyn((R)) Africa) designed for use in the region is developed and employed in the field in a pragmatic Phase III clinical trial in the Republic of Benin.
80 citations
TL;DR: It is concluded that EchiTAb-Plus-ICP has a good preclinical neutralizing profile against homologous and heterologous viperid venoms from other sub-Saharan African locations and constitutes a promising therapeutic option for the treatment of snakebite envenoming in this region.
80 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 2 |
| 2020 | 2 |
| 2019 | 3 |
| 2017 | 4 |
| 2015 | 1 |
| 2014 | 1 |