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The Mexican black-tailed rattlesnake Crotalus molossus nigrescens is distributed in the Mexican plateau. Its venom is known to cause hemolysis and presents fibrinogen coagulase, collagenase and fibrinolytic activities. These activities may be associated with hemostatic alterations, such as platelet aggregation, hemolysis and fibrinolysis, often described in ophidic accidents. However, the mechanisms of action of the C. m. nigrescens venom remain unclear. In this study we investigated the in vitro hemotoxic, neurotoxic, and vasculotoxic effects of the venom. We found that this venom produces two types of hemolytic responses, Oxyhemoglobin release and Methemoglobin formation. As a result of the cytotoxicity to endothelial cells produces morphological biphasic toxicity. The first step in this process is characterized by morphological changes, as well as the loss of cellular adhesion and reduction in thickness. The second phase is characterized by massive cellular aggregation and death. It also induced laminin, type IV collagen, perlecan and nidogen degradation. However, the venom did not modulate the muscular fetal and neuronal nicotinic acetylcholine receptors activity. Thus, we concluded that the C. m. nigrescens venom produced hemolysis and hemorrhages via degradation of the basement membrane components and endothelial cell cytotoxicity, but not by neurotoxicity at the receptor level in nicotinic acetylcholine receptors.

Entre las especies del género Acacias, la Acacia melanoxylon o aromo australiano y la Acacia dealbata o aromo chileno, son dos especies aclimatadas en Chile con un interesante potencial industrial. En este trabajo, se estudian programas de secado a temperaturas convencionales y la calidad de la madera seca de A. melanoxylon y A. dealbata. Experimentalmente son realizados 8 ensayos de secado a temperaturas convencionales, usando un horno de secado convectivo de 0.3 m³ de capacidad. El diseño experimental incluye como factores variables la especie (A. melanoxylon y A. dealbata), el espesor de la madera (25 y 50 mm) y el tipo de corte (tangencial y radial). Los resultados indican que para 25 o 50 mm de espesor, la A. melanoxylon y la A. dealbata, en corte radial y tangencial se dejan secar satisfactoriamente bajo un mismo programa de temperaturas convencionales. La calidad de la madera seca se ve favorecida por la carencia de colapso y la baja anisotropía de la contracción transversal. Acacia melanoxylon and Acacia dealbata are two Australian species well acclimated in Chile, both wood species with an interesting industrial potential. In this work, has been studied kiln drying runs and the wood drying quality of the sawn wood of Acacia melanoxylon and Acacia dealbata during kiln drying at conventional temperatures. Eight tests of kiln drying to conventional temperatures are made, using a convective drying of 0,3 m³ of capacity. The experimental design includes as variable the species (A. melanoxylon an A. dealbata), the wood thickness (25 and 50 mm) and the cut-type (flatsawn-wood and quartersawn-wood). The wood drying quality on the basis of European and Chilean standards is evaluated. The results show that for a same thickness, both species A. melanoxylon and A. dealbata, in flatsawn and quartersawn-wood could be satisfactorily kiln dryied under a similar program of conventional temperatures. The wood drying quality is performed due to both species are free of collapse and they are an low transversal shrinkage.