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The snake venom gland is the place for the synthesis, storage, and secretion of a complex mixture of proteins and peptides, i.e., the venom. The morphology of the gland has been revealed by classical histology and microscopic studies. However, knowledge about the gland's cellular secretory and functional processes is still incomplete and has so far been neglected by the omics disciplines. We used autofocusing atmospheric-pressure matrix-assisted laser desorption/ionization (AP-SMALDI) mass spectrometry imaging (MSI) to investigate endogenous biomolecular distributions in the venom glands of the saw-scaled viper, Echis carinatus sochureki , employing different sample preparation methods. Fresh-freezing and formalin-fixation were tested for the gland to obtain intact tissue sections. Subsequently, MSI was conducted with 12 μm pixel resolution for both types of preparations, and the lateral distributions of the metabolites were identified. Experiments revealed that lipids belonging to the classes of PC, SM, PE, PS, PA, and TG are present in the venom gland. PC (32:0) and SM (36:1) were found to be specifically located in the areas where cells are present. The snake venom metalloprotease inhibitor pEKW ( m / z 444.2233) was identified in the venom by top-down LC-MS/MS and localized by MALDI-MSI in the gland across secretory epithelial cells. The peptide can inhibit the venom's enzymatic activity during long-term storage within the venom gland. With a high degree of spectral similarities, we concluded that formalin-fixed tissue, in addition to its high ability to preserve tissue morphology, can be considered as an alternative method to fresh-frozen tissue in the case of lipid and peptide MS imaging in venom gland tissues.

The amount of venom that a snake can inject is related to its body size. The body size is related to head size and to the distance between fangs. To correlate snake body size, distance between fangs and distance between puncture wounds with the venom yield (and consequently with the venom dose potentially injected in a single snakebite), we studied these variables in two species of public health importance in South America, Bothrops (Rhinocerophis) alternatus, and Crotalus durissus terrificus. In all cases a positive correlation was observed between body length, fang separation distance, distance between puncture wounds and venom yield, with a regression coefficient over 0.5 for Bothrops alternatus and over 0.6 for Crotalus durissus terrificus in all cases, being the relation distance between punctures wounds and venom yield of 0.54 and 0.69 respectively. The difference between fang separation and puncture separation was never greater than 30%, with a mean difference around 13%. The strong relationships between body size, fang separation and venom yield may be useful for planning potential venom production in serpentariums. In addition, because puncture mark separation gives an approximate idea of the size of the snake, this provides a rough idea of the size of the snake that produced a bite and the potential amount of venom that could have been injected., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Envenoming by Protobothrops mucrosquamatus and Viridovipera stejnegeri accounts for the majority of venomous snakebites in Taiwan. We conducted a retrospective study to systematically examine the clinical manifestations and responses to antivenom therapy after P. mucrosquamatus and V. stejnegeri envenoming. Information on demographic characteristics, treatments, and systemic/local complications were abstracted from medical charts between 1991 and 2006. One hundred forty-nine patients with P. mucrosquamatus envenoming and 51 with V. stejnegeri envenoming were eligible for the final analysis, and they differed in terms of patient age, bite site, local bruising, proportion of patients needing >/= 3 vials of antivenom, and mean hospital stay. Univariate analysis revealed that P. mucrosquamatus envenoming had a higher risk of developing rhabdomyolysis, cellulitis, necrosis, and skin graft. Our findings suggested that P. mucrosquamatus envenoming was associated with a greater risk of severe clinical events, and monitoring for major clinical complications would be recommended.

In Kerala, south-western India, five patients developed systemic envenoming after bites by hump-nosed pit vipers (Hypnale hypnale), proved by identification of the snakes responsible. Two of the dead snakes had been misidentified as saw-scaled vipers (Echis carinatus), while three had remained unidentified. Symptoms of local envenoming were pain, swelling, haemorrhagic blistering, bruising and regional lymphadenopathy. Systemic symptoms included headache, nausea, vomiting and abdominal and chest pain. There was evidence of haemostatic dysfunction (coagulopathy, fibrinolysis, thrombocytopenia or spontaneous systemic haemorrhage) in all cases and of microangiopathic haemolysis in two. Two patients were haemodialysed for acute renal failure, one of whom developed pulmonary oedema requiring mechanical ventilation. In India, H. hypnale has not previously been regarded as a cause of frequent or potentially dangerous envenoming. Its medical importance has been overlooked throughout its geographical range, probably because of confusion with other small species. No specific antivenom exists, yet most patients are treated with non-specific antivenoms, risking reactions without hope of benefit. An effective antivenom is urgently needed in south India and in Sri Lanka, where this species is also a common cause of bites.

The primary culture of the Vipera berus poison-secretory parotid gland has been obtained. The morphology of the intact secretory epithelium and epithelial cells cultured in different conditions has been examined by light and electron microscopy. The secretory epithelium cells were able to survive in the cultural medium and to adapt to in vitro conditions maintaining their nearly normal ultrastructure corresponding to the stage of active poison secretion commonly observed in epithelial cells of the native gland.

Enzyme activities tested in the venom gland extract of Azemiops feae snake are similar to those of viperine venoms, except that Azemiops venom has no blood clotting, haemorrhagic or myolytic activities. The venom gland exhibits the characteristic feature of a viperine gland, but the fangs possess a ridge at the tip laterally to the venom orifice and a blade-like structure on the back seen only in some opisthoglyphous and Atractaspidae snakes.