(1) Coelenterate and poriferan connective tissues were devoid of these acid polysaccharides.
(2) Many coelenterates can injure human skin by means of their nematocytes.
(3) The system of a related anthozoan coelenterate, the sea pansy Renilla reniformis, however, is oxygen dependent, requiring two organic components, luciferin and luciferase.
(4) A Ca2+-triggered luciferin-binding protein (BP-LH2) from the bioluminescent marine coelenterate, Renilla reniformis, has been purified by conventional methods.
(5) There are various types of photoproteins: the photoproteins of coelenterates, ctenophores and radiolarians require Ca2+ to trigger their luminescence; the photoproteins of the bivalve Pholas and of the scale worm appear to involve superoxide radicals and O2 in their light-emitting reactions; the photoprotein of euphausiid shrimps emits light only in the presence of a special fluorescent compound; the photoprotein of the millipede Luminodesmus, the only known example of terrestrial origin, requires ATP and Mg2+ to emit light.
(6) Glutamate dehydrogenases detected in tissue extracts of a broad sample of coelenterate species all require NADP(H) as a co-substrate, rather than being capable of using either NAD(H) or NADP(H).
(7) Mucus is an ubiquitous polymer hydrogel that functions as a protective coat on the surface of integument and mucosa of species ranging from simple animals (such as coelenterates) to mammals.
(8) In the hydrozoan coelenterate Obelia geniculata, epithelial cell action potentials trigger light emission from photocyte effector cells containing obelin, an endogenous calcium-activated photoprotein.
(9) We studied by immunohistochemistry three cases of delayed envenomation by coelenterates.
(10) These case histories demonstrate that multiple recurrent eruptions may follow solitary envenomations by different subphyla of coelenterates, that the initial eruption induced by the sting may be delayed by the administration of high doses of systemic corticosteroids, and that an immunologic reaction in both the B and T cell systems can follow jellyfish envenomation.
(11) The regeneration of coelenterate photoproteins in this manner probably takes place in vivo, utilizing stored coelenterazine.
(12) At least 100 of the approximately 9,000 species of coelenterates are dangerous to humans.
(13) Hydra viridis (= Chlorohydra viridissima) the freshwater coelenterate, is symbiotic.
(14) Some years ago our laboratory reported that the bioluminescence reaction in the ctenophores which had long eluded definition involved a calcium activated photoprotein similar in many respects to that found in other coelenterates, notably Aequorea.
(15) Skin tumor-promoting agents, including the 12-O-tetradecanoylphorbol-13-acetate (TPA)-type tumor promoters, such as diterpine phorbol esters, teleocidin and aplysiatoxin, and a non-TPA-type tumor promoter (the newly described palytoxin, present in the coelenterate of the genus Palythoa), stimulated arachidonic acid metabolism by rat liver cells in culture.
(16) Their distribution among lipids of a number of species of different classes of coelenterates from the northern and tropical seas, among neutral and polar lipids of these organisms was investigated.
(17) By using immunocytochemistry and radioimmunoassays, several substances resembling vertebrate or invertebrate neuropeptides have been found in the nervous systems of coelenterates.
(18) Sudden death following coelenterate envenomation is not uncommon in Australia where the Pacific box jellyfish is indigenous.
(19) The principal sources of these agents are bacteria, higher fungi, cnidarians (coelenterates) and the venoms of snakes, insects and other arthropods.
(20) The recurrent eruptions appeared several days after the primary exposure without contact with any offending coelenterate.
Nematocyst
Definition:
(n.) A lasso cell, or thread cell. See Lasso cell, under Lasso.
Example Sentences:
(1) Nematocyst capsules and everted threads from both species contained levels of glycine and proline-hydroxyproline characteristic of vertebrate collagens.
(2) Purified nematocyst capsules and threads are rich in hydroxyproline, and dissolved by disulfide reducing agents.
(3) Investigation on important medusae and the chemistry of their nematocyst venoms have been expanding.
(4) They are considered to be the principal toxins injected by C. fleckeri during nematocyst discharge and appear to be different from the C. fleckeri toxins described by other workers.
(5) A new cytolysin has been isolated from the nematocysts of the jellyfish, Rhizostoma pulmo, and named rhizolysin.
(6) A comparison of methods for preparing a jellyfish nematocyst suspension from sea nettle (Chrysaora quinquecirrha) fishing tentacles at the beachside was conducted.
(7) Evidence obtained from the osmotic behavior of nematocysts, as well as data from in vitro exchange of their cations, are consistent with a physicochemical model in which the internal osmotic pressure of nematocysts and thus their ability to discharge is governed by the cationic composition of the content and the salt concentrations in the environment.
(8) Cnidocytes, the stinging cells of cnidarians, discharge nematocysts in response to physical contact accompanied by the stimulation of specific chemoreceptors.
(9) In the tentacles, neurons with long processes contacted up to five different batteries of nematocysts.
(10) It is suggested that they may also be present as predominant components in nematocysts of other cnidarian species and thus might represent a class of compounds which is characteristic for a whole phylum of the animal kingdom.
(11) Electrophoretic characterization of nematocyst extracts allows resolution of small proline-rich polypeptides that correspond in size to the cloned sequences.
(12) The major protein component present in the capsule and thread of a sea anemone nematocyst consists of monomers of a collagen-like protein linked by disulfide bonds.
(13) First-aid measures designed to prevent additional nematocyst rupture are species-specific.
(14) One such defective strain, called nem-4, contains virtually no stenoteles, one of the four types of nematocysts present in hydra, in its tentacles.
(15) The CSMs become predisposed to initiate nematocyst discharge into static (i.e., nonvibrating) test probes in the presence of submicromolar free and conjugated N-acetylated sugars, a process referred to as sensitization.
(16) It is suggested that the high concentration of calcium in the nematocysts accounts for their staining by cobalt and morin.
(17) Crude extract prepared from isolated and purified nematocysts (stenoteles, desmonemes, isorhizas) of Hydra attenuata Pall.
(18) Contrary to some previous reports in the literature, it has been found that spirocysts normally discharge by eversion, as do nematocysts.
(19) Unlike most nematocysts, undischarged spirocyst threads bear hollow tubules rather than spines.
(20) The toxins are labile when released from nematocysts and they lose all myotoxic activity within 3 days at 5 degrees C. They can also be isolated chromatographically from crude extracts of the contents of mixed nematocysts of C. fleckeri.