The insects of the order Hymenoptera (bees, wasps, and ants) are classified in two groups, based on their life history: social and solitary. The venoms of the social Hymenoptera evolved to be used as defensive tools to protect the colonies of these insects from the attacks of predators. Generally they do not cause lethal effects but cause mainly inflammatory and/or immunological reactions in th...

Venoms are the secretion of venomous animals, which are synthesized and stored in specific areas of their body i.e., venom glands. The animals use venoms for defense and/or to immo‐ bilize their prey. Most of the venoms are complex mixture of biologically active compounds of different chemical nature such as multidomain proteins, peptides, enzymes, nucleotides, lipids, biogenic amines and other...

Snake venoms are known to contain a number of enzymes (l-3). Attempts have been made to correlate the toxicity of snake venoms with their enzymic activity, e.g. between nucleases and toxicity (4), phospholipase A and neurotoxic action of cobra venom (5), and proteolytic and coagulant activity and toxicity (6-8). Most of these studies have been carried out on whole venoms or after elimination of...

Scorpions, at least the species of the family Buthidæ whose venoms are better known, appear as animals that have evolved very little over time. The composition of their venoms is relatively simple as most toxins have a common structural motif that is found in other venoms from primitive species. Moreover, all the scorpion venom toxins principally act on membrane ionic channels of excitable cell...

Background: Poisoning due to the bites and stings of venomous snakes and scorpions is a neglected public health problem, particularly in rural areas. Poor health facilities and inadequate knowledge of health care personnel are the major factors that result in envenomated human victims not receiving adequate care and medical attention. There is a great need for up-to-date and effective healthcar...

Cardiovascular effects (e.g., tachycardia, hypo- and/or hypertension) are often clinical outcomes of snake envenoming. Malayan krait (Bungarus candidus) envenoming has been reported to cause cardiovascular effects that may be related to abnormalities in parasympathetic activity. However, the exact mechanism for this effect has yet to be determined. In the present study, we investigated the in v...

Envenomation of humans by snakes is a complex and continuously evolving medical emergency, and treatment is made that much more difficult by the diverse biochemical composition of many venoms. Venomous snakes and their venoms also provide models for the study of molecular evolutionary processes leading to adaptation and genotype-phenotype relationships. To compare venom complexity and protein s...

The Myxozoa comprise over 2,000 species of microscopic obligate parasites that use both invertebrate and vertebrate hosts as part of their life cycle. Although the evolutionary origin of myxozoans has been elusive, a close relationship with cnidarians, a group that includes corals, sea anemones, jellyfish, and hydroids, is supported by some phylogenetic studies and the observation that the dist...

Cnidarian-dinoflagellate photosynthetic symbioses are fundamental to biologically diverse and productive coral reef ecosystems. The hallmark of this symbiotic relationship is the ability of dinoflagellate symbionts to supply their cnidarian host with a wide range of nutrients. Many aspects of this association nevertheless remain poorly characterized, including the exact identity of the transfer...