The toxicity of Cnidaria is a subject of concern due to its influence on humans. In particular, jellyfish blooms can highly affect human economical activities, such as bathing, fishery, tourism, etc., as well as the public health. Stinging structures of Cnidaria (nematocysts) produce remarkable effects on human skin, such as erythema, swelling, burning and vesicles, and at times further severe ...

Cnidarian medusae, commonly known as jellyfish, represent the earliest known animal taxa to achieve locomotion using muscle power. Propulsion by medusae requires the force of bell contraction to generate forward thrust. However, thrust production is limited in medusae by the primitive structure of their epitheliomuscular cells. This paper demonstrates that constraints in available locomotor mus...

There is now strong evidence that myxozoans have evolved from free-living cnidarians but until recently their higher level relationships have been the subject of considerable controversy. This chapter reviews the morphological and molecular evidence that has contributed to problems in placement and how further collective support has finally resolved their cnidarian affinity. We then consider th...

The production of natural toxins is an interesting aspect, which characterizes the physiology and the ecology of a number of marine species that use them for defence/offence purposes. Cnidarians are of particular concern from this point of view; their venoms are contained in specialized structures--the nematocysts--which, after mechanical or chemical stimulation, inject the venom in the prey or...

Phospholipase A2 (PLA2) is an enzyme present in snake and other venoms and body fluids. We measured PLA2 catalytic activity in tissue homogenates of 22 species representing the classes Anthozoa, Hydrozoa, Scyphozoa and Cubozoa of the phylum Cnidaria. High PLA2 levels were found in the hydrozoan fire coral Millepora sp. (median 735 U/g protein) and the stony coral Pocillopora damicornis (693 U/g...

Cellular motility is essential for microscopic parasites, it is used to reach the host, migrate through tissues, or evade host immune reactions. Many cells employ an evolutionary conserved motor protein- actin, to crawl or glide along a substrate. We describe the peculiar movement of Sphaerospora molnari, a myxozoan parasite with proliferating blood stages in its host, common carp. Myxozoa are ...

The Zoanthids are an order of cnidarians whose venoms and toxins have been poorly studied. Palythoa caribaeorum is a zoanthid commonly found around the Mexican coastline. In this study, we tested the activity of P. caribaeorum venom on voltage-gated sodium channel (NaV1.7), voltage-gated calcium channel (CaV2.2), the A-type transient outward (IA) and delayed rectifier (IDR) currents of KV chann...

About 4,000 to 6,000 venomous snakebites occur each year in the United States. Although these envenomations (also known as envenomings) are rarely fatal, about 70 percent require antivenom therapy. Few evidence-based guidelines are available for the management of envenomation. Antivenom therapy is the cornerstone of management for hemorrhagic or coagulopathic envenomation from pit vipers (with ...

Jellyfish venoms are rich sources of toxins designed to capture prey or deter predators, but they can also elicit harmful effects in humans. In this study, an integrated transcriptomic and proteomic approach was used to identify putative toxins and their potential role in the venom of the scyphozoan jellyfish Chrysaora fuscescens. A de novo tentacle transcriptome, containing more than 23,000 co...