(n.) A binary compound of selenium, or a compound regarded as binary; as, ethyl selenide.
Example Sentences:
(1) From this work it can be concluded that diallyl selenides are readily cleaved by mild oxidation, whereas dialkyl selenides and benzyl alkyl selenides can only be cleaved when the alkyl part of the selenide has an electron-withdrawing group next to the beta-carbon from selenium.
(2) This assay employed high pressure liquid chromatography separation and quantitation of the trimethylselenonium ion produced by thioether methyltransferase acting on S-adenosylmethionine and dimethyl selenide.
(3) The results support the hypothesis that H2Se or a similarly reduced selenide is the product of selenite metabolism by rat erythrocytes.
(4) It was concluded that Fraction C contains a methyltransferase acting on small amounts of hydrogen selenide produced non-enzymically by the reaction of selenite with GSH, and that stimulation by Fraction A results partly from the NADPH-linked formation of hydrogen selenide catalyzed by glutathione reductase present in Fraction A.
(5) The dependence of reaction velocity on ATP concentration shows sigmoidal kinetics, whereas dependence on selenide concentration obeys Michaelis-Menten kinetics indicating a Km value of 46 microM for selenide.
(6) Both appear to inhibit Se volatilization by reacting with the selenide product(s).
(7) The selenium found in the liver subcellular organelle fractions was present in at least three oxidation states: acid-volatile selenium, assumed to be selenide, zinc-hydrochloric acid-reducible selenium, assumed to be selenite, and higher oxidation states of selenium and organic derivatives, called selenate for convenience.
(8) Investigation by energy-dispersive analysis of X-rays (EDAX) indicated the precipitation of silver as selenide.
(9) Considering the effects of diet on the various enzymes known from our previous studies to be involved in dimethyl selenide synthesis, it was concluded that the enhanced ability of rats fed stock diet to synthesize dimethyl selenide results from the induction of a liver microsomal enzyme, apparently a Se-methyltransferase, caused by unknown substances in the stock diet.
(10) Short-term toxicity tests were carried out for sulfide, selenide, and their methylated derivatives; the monomethylated forms were somewhat more toxic than the nonmethylated or dimethylated compounds.
(11) The microsomal activity apparently results from a Se-methyltransferase, possibly a dithiol protein, that methylates hydrogen selenide produced enzymically by the soluble fraction or non-enzymically when a sufficiently high concentration of GSH is used.
(12) The former is characterized by an increase in a 58 K selenoprotein, whereas the latter by an increase in volatile selenides.
(13) Intracerebral injections of both sodium selenide (Na2Se) and sodium selenite (Na2SeO3) have been successfully used; however, sodium selenite had a rather toxic effect on the injected tissue.
(14) In vitro experiments suggested that trace amounts of hydrogen selenide, which is an intermediate of selenite metabolism, probably induced hemolysis.
(15) Although arsenic decreased selenium toxicity under most conditions, there is a pronounced synergistic toxicity between arsenic and two methylated selenium metabolites, trimethylselenonium ion or dimethyl selenide.
(16) Sodium selenide is therefore recommended as the compound of choice.
(17) The production of acid-volatile selenide (apparently H2Se) was catalyzed by glutathione reductase in an anaerobic system containing 20 mM glutathione, 0.05 mM sodium selenite, a TPNH-generating system, and microgram quantities of highly purified yeast glutathione reductase.
(18) By using isolated guinea-pig taenia coli preparations, the effects of methylmercuric chloride and bis (methylmercuric) selenide on contractile responses to nerve and direct stimulation were investigated.
(19) These results are consistent with the hypothesis that the active form of Se may be selenide and that the selenide may form part of the active centre of an uncharacterized class of catalytically active non-haem-iron proteins that are protected from oxidation in vivo by vitamin E.
(20) The comparison between the 2-chloroethyl sulfides and selenides 1-4 revealed the markedly enhanced nucleophilicity of selenium (Se) over sulfur (S) by two or more orders of magnitude.
Selenite
Definition:
(n.) A salt of selenious acid.
(n.) A variety of gypsum, occuring in transparent crystals or crystalline masses.
Example Sentences:
(1) After a resuscitation period of 4 h, the medium was made selective by addition of either sodium thiosulfate, bile salts and iodine, or sodium selenite and L-cystine.
(3) This inhibition was partially reversed on addition of the translocated substrates sulphate or selenate to the external medium: selenite which is not translocated does not protect against DIDS inhibition.
(4) Pregnant hamsters were treated with selenite, selenate, and selenomethionine during the critical stages of embryogenesis.
(5) The less toxic seleno-di-N-acetylglycine was needed in larger molar doses and did not act as rapidly as selenite.
(6) DNA methylase isolated from selenite treated animals had only 43% of the activity as enzyme from control rats.
(7) The deposition of selenium (Se) in erythrocyte proteins was studied in rats fed Se as sodium selenite, selenocystine, selenomethionine (Se-Met), high Se wheat or selenium-enriched yeast.
(8) The effects of cadmium as cadmium acetate and selenium as sodium selenite on glucose output, cell viability, and glutathione levels in rat hepatocytes were evaluated.
(9) Thus, selenite gave higher radioactivity in myelin, then followed by the light synaptosomal and the vesicular fraction.
(10) The pre-incubation with sodium selenite reduces the respiratory index in guinea-pig cardiac mitochondria when alpha-ketoglutarate and glutamate are used as substrates.
(11) The severity of ischaemic lesion could be reduced by FRLP inhibition using antioxidative agents of sharply differing chemical nature (sodium selenite, alpha-tocopherol a.o.).
(12) An initial series of experiments, with hepatocytes in suspension, indicated that selenite-induced DNA fragmentation was oxygen dependent and could be inhibited by cyanide, HgCl2 and CuDIPS.
(13) Selenomethionine (10 ppm Se) resulted in an incidence of 13.1% malformations that were often multiple, whereas sodium selenite (10 and 25 ppm Se) resulted in 3.6 and 4.2% malformations.
(14) The increase or decrease of the sodium selenite dose by the factor ten had no effect on the preservation of the contractility of fragments of the heart-muscle after storage -196 degrees C in comparison to the control group.
(15) Percent hemolysis is marked decreased after a three-hour incubation of the whole blood with addition of selenomethionine as well as sodium selenite with tocopherole in combination before cryopreservation.
(16) The Food and Drug Administration gave approval in 1974 for the oral administration of supplemental selenium as either sodium selenite or sodium selenate to certain classes of swine and poultry.
(17) The cause of death by selenite was apparently due to the respiratory failure.
(18) Nevertheless, DNA and RNA polymerases, the enzymes responsible for this synthesis, are insensitive to inhibition by selenite.
(19) Sodium selenite is able to reduce it towards the normal level.
(20) is able to grow well up to 3% sodium selenite-containing media.