I n retrospect, the history of selenium biochemistry does not differ greatly from the study of a number of other trace elements in that it occurred over many years, progressing from periods of little general interest to widespread concern regarding toxicity problems and eventually to recognition of selenium as an essential nutrient for many forms of life. My involvement in studies on selenium m...

Increasing speciation demands in clinical chemistry, toxicology and nutrition have made the determination of the total elements in a sample inadequate; the amount of an element and the chemical forms in which it is present need to be known. Inductively coupled plasma mass spectrometry (ICP-MS) was used after high-performance liquid chromatographic (HPLC) separation, as was electrospray ionizati...

The generation of superoxide anion or hydroxyl radical derived from the organic selenium compounds selenomethionine, selenoethionine, selenocystine, selenocystamine and selenocysteine-glutathione selenenyl sulfide (CySeSG) was investigated by the electron spin resonance (ESR) technique with 5,5-dimethyl-1-pyrroline Noxide (DMPO) as a spin trapping agent. The intensity of ESR signals of DMPO-OOH...

The requirement of the trace element selenium for life and its beneficial role in human health has been known for several decades. This is attributed to low molecular weight selenium compounds, as well as to its presence within at least 25 proteins, named selenoproteins, in the form of the amino acid selenocysteine (Sec). Incorporation of Sec into selenoproteins employs a unique mechanism that ...

The 77Se NMR chemical shifts (δobsd(Se)) of p-YC6H4SeMe (1: Y ) H (a), OMe (b), Me (c), Cl (d), Br (e), COOR (f), and NO2 (g)) and p-YC6H4SePh (2) were determined or redetermined in chloroform-d. The δobsd(Se) values of 2, p-YC6H4SeR (R ) CN (3), Bz (4), H (5), Br (6), Et (7), C6H4Y-p (8), CHdCH2 (9), CHd CHCl-t (10), and CHCH2CCl2-cyclo (11)), 1,1′-[8-(p-YC6H4Se)C10H6Se]2 (12), and 1-(MeSe)-8-...

BACKGROUND As an essential trace element selenium plays a significant role in many physiological functions of the organs. It is found within muscles as selenocystein in selenoprotein N, which is involved in redox-modulated calcium homeostasis and in protection against oxidative stress. METHODS The effects of two different selenium compounds (selenate and NanoSe in 0.5 and 5 ppm concentration ...

Exposure of Escherichia coli or mammalian cells to H2O2 results in cell death due to iron-mediated DNA damage. Since selenium compounds have been examined for their ability to act as antioxidants to neutralize radical species, and inorganic selenium compounds are used to supplement protein mixes, infant formula, and animal feed, determining the effect of these compounds on DNA damage under cond...

Selenium-accumulating plants such as Brassica juncea (Indian mustard) concentrate the element in plant shoots and roots. Such behavior may provide a cost-effective technology to clean up contaminated soils and waters that pose major environmental and human health problems (phytoremediation). Such ability to transform selenium into bioactive compounds has important implications for human nutriti...

The keto-enol type tautomerism in anti-thyroid drugs and their selenium analogues are described. The commonly used anti-thyroid drug methimazole exists predominantly in its thione form, whereas its selenium analogue exists in a zwitterionic form. To understand the effect of thione/thiol and selone/selenol tautomerism on the inhibition of peroxidase-catalysed reactions, we have synthesized some ...