Abstract in English:Death caused by scorpion envenoming (Buthidae family) is a common event in tropical and subtropical countries. Severe scorpion envenoming causes an autonomic storm resulting in a massive release of catecholamines, angiotensin II, glucagon, cortisol, and changes in insulin secretion. As a consequence of these changes in the hormonal milieu, scorpion envenoming results in a syndrome of fuel energy deficits and an inability of the vital organs to utilize the existing metabolic substrates, which causes myocardial damage, cardiovascular disturbances, peripheral circulatory failure, pulmonary oedema, and many other clinical manifestations alone or in combination, producing multi-system-organ-failure (MSOF) and death. Insulin-glucose infusion or antivenom administration through the release of insulin seems to be the physiological basis for the control of the metabolic response when that has become a determinant to survival of scorpion sting victims.
Abstract in English:Toads (order: Anura; family: Bufonidae; genus: Bufo) are distributed throughout the world, but more species are found in areas of tropical and humid temperate climates. Although toads do not have a venom inoculation system, they are venomous animals because the glands covering the whole surface of their bodies secrete a milk-like venom of which composition is not yet completely known. Some of these glands are the bilateral glands located in post-orbital position. These glands, which are somewhat diamond-shaped and can be seen by the naked eye, are known as parotids. Toad envenoming in dogs may cause local and systemic alterations and may cause death by cardiac ventricular fibrillation. The electrocardiographic alterations observed consist of gradual deterioration of the normal standards with progressive appearance of negative ventricular deflections that can result in ventricular fibrillation and death if the envenomed dog is not promptly treated. Traditional therapy consists mainly of administration of atropine and propranolol; the latter used to prevent ventricular fibrillation.
Abstract in English:Some properties of a Africanized honeybee venom proteases were determined by enzymatic assays in solution, electrophoresis in SDS-PAGE, and gel filtration. Bee venom extracts were obtained by reservoir disruption, selective dialysis (cut off 12 kDa) to eliminate small components, such as the protease inhibitor present in the venom, and then fractionation of the dialyzed extract by gel filtration on a Sephadex G-100 column. The optimal conditions for the caseinolytic assays were pH 9.5, 2-hour digestion at 37 °C, and 1% casein concentration. The proteolytic activity was also determined by electrophoresis in SDS-PAGE with co-polymerized gelatin with three major bands of 66.0, 41.6, and 25.1 kDa. A principal serine-protease-like mechanism was revealed in the enriched fraction of proteolytic activity.
Abstract in English:Lethal Toxin Neutralizing Factor (LTNF), isolated from opossum with having molecular weight 63 kDa, is a potent antidote for animal, plant, and bacterial toxins. This communication deals with the identification of a small fragment of LTNF eliciting the anti-lethal activity of animal, plant, and bacterial toxins when tested in mice. Purified LTNF was treated with trypsin to cause fragmentation at the arginine and lysine sites. The fragments were separated by high-performance liquid chromatography (HPLC) and were tested against anti-LTNF for binding affinity by enzyme-linked immunosorbent test (ELISA). The fragment showing the most binding to anti-LTNF was sequenced. Synthetic peptides consisting of 15 and 10 amino acids from the N-terminal were constructed and designated as LT-15, with amino acid sequence Leu-Lys-Ala-Met-Asp-Pro-Thr-Pro-Pro-Leu-Trp-Ile-Lys-Thr-Glu, and LT-10, with sequence Leu-Lys-Ala-Met-Asp-Pro-Thr-Pro-Pro-Leu. Death due to intramuscular (IM) injection of predetermined lethal doses of toxins derived from animal, plant, and bacteria was prevented treating the mice with synthetic peptides LT-15 and LT-10. The lethality was inhibited when the treatment was given before or after the toxin injection. Synthetic LTNF can be made in abundance and should become a universal therapy against intoxication caused by animal, plant, and bacteria.
Abstract in English:This paper analyzes the summer and winter total protein content of 7, 14, 21, 28, 35, and 40-day old Apis mellifera L. worker venom glands before (control) and 24 and 96 hours after applying electrical shocks for venom extraction (experimental). During venom extraction, 7-day old workers responded more slowly and weakly to electrical shocks. This response intensifies with age, so that the workers approaching 20 days old respond faster and more aggressively to the shocks. Statistical analysis, using the non-parametric Wilcoxon and Kruskall-Wallis tests and complemented by the Jonckheere test, showed that the protein content varied from one age to another in the experimental group, which was well distinguishable from the values in the control Group in summer and winter. Summer values at all ages were always higher than those detected in winter in both groups. This variation seems to indicate the occurrence of more than one winter glandular development cycle. Histological studies showed secretion in the lumen of the control Group secretory tubes and reservoirs. The experimental group only showed vestigial secretion in the collapsed reservoirs at all ages, except at 7 days. These workers, which reacted less efficiently to electrical shocks, showed secretion in the lumen, reservoir, and tubes, even after the application of electrical shocks. During the 96 hours following the electrical shocks, a slight protein replacement was seen at some ages. This, although higher in summer than in winter, was much lower than the level detected in the control group at all ages. The significantly lower values were frequent in the older workers 96 hours after extraction and could reflect reabsorption or degradation of proteins from glandular secretion due to aging. Our results show that venom extraction is more productive in summer using older workers. However, their capacity of replacing protein eliminated during stinging of the substrate, in response to shocks is shown to be low, as demonstrated for other analyzed bees.
Abstract in English:This paper describes a new species of scorpion of the Tityus genus, Tityus caripitensis (Scorpionida: Buthidae). This species can be found in Caripito, Bolívar municipality of Monagas State, Venezuela. The number of species of Tityus genus in Venezuela has increased to 37 with the inclusion of Tityus caripitensis. A diagnosis of the most significant morphological characteristics of both males and females of this new species, which has been causing serious envenomings in the Bolívar and Punceres municipalities, has been carried out.