Green Tea Increases the Concentration of Total Mercury in the Blood of Rats following an Oral Fish Tissue Bolus.

Fish has many health benefits but is also the most common source of methylmercury. The bioavailability of methylmercury in fish may be affected by other meal components. In this study, the effect of green tea on the bioavailability of methylmercury from an oral bolus of fish muscle tissue was studied in rats and compared to a water treated control group and a group treated with meso-2,3-dimercaptosuccinic acid (DMSA), a compound used medically to chelate mercury.

Fatty acid profiles of commercially available finfish fillets in the United States.

Fillets of 76 finfish species (293 composites of three fish) were obtained from commercial seafood vendors in six regions of the United States (i.e., Great Lakes, Mid-Atlantic, New England, Northwest, Southeast, and Southwest).

Gamma-tocotrienol induces apoptosis and autophagy in prostate cancer cells by increasing intracellular dihydrosphingosine and dihydroceramide.

Although cell-based studies have shown that γ-tocotrienol (γTE) exhibits stronger anticancer activities than other forms of vitamin E including γ-tocopherol (γT), the molecular bases underlying γTE-exerted effects remains to be elucidated. Here we showed that γTE treatment promoted apoptosis, necrosis and autophagy in human prostate PC-3 and LNCaP cancer cells. In search of potential mechanisms of γTE-provoked effects, we found that γTE treatment led to marked increase of intracellular dihydroceramide and dihydrosphingosine, the sphingolipid intermediates in de novo sphingolipid synthesis pathway but had no effects on ceramide or sphingosine.

Gamma-tocotrienol and gamma-tocopherol are primarily metabolized to conjugated 2-(beta-carboxyethyl)-6-hydroxy-2,7,8-trimethylchroman and sulfated long-chain carboxychromanols in rats.

The metabolism of gamma-tocotrienol (gamma-TE) and gamma-tocopherol (gamma-T) was investigated in human A549 cells and in rats. Similar to gamma-T, A549 cells metabolized gamma-TE to sulfated 9'-, 11'-, and 13'-carboxychromanol and their unconjugated counterparts. After 72-h incubation with the cells, 90% of long-chain carboxychromanols in the culture media from gamma-TE, but <45% from gamma-T, were in the sulfated form.

Optimization of the enzymatic hydrolysis and analysis of plasma conjugated gamma-CEHC and sulfated long-chain carboxychromanols, metabolites of vitamin E.

Natural forms of vitamin E are metabolized by omega-hydroxylation and beta-oxidation of the hydrophobic side chain to generate urinary-excreted 2-(beta-carboxyethyl)-6-hydroxychroman (CEHC) and CEHC conjugates (sulfate, glucuronide, or glucoside). We recently showed that sulfated long-chain carboxychromanols, the conjugated intermediate beta-oxidation products, are formed from tocopherols and tocotrienols in human cells and in rats. CEHC conjugates have been quantified after being converted to its unconjugated counterpart by sulfatase/glucuronidase.

Long-chain carboxychromanols, metabolites of vitamin E, are potent inhibitors of cyclooxygenases.

Cyclooxygenase (COX-1/COX-2)-catalyzed eicosanoid formation plays a key role in inflammation-associated diseases. Natural forms of vitamin E are recently shown to be metabolized to long-chain carboxychromanols and their sulfated counterparts. Here we find that vitamin E forms differentially inhibit COX-2-catalyzed prostaglandin E(2) in IL-1beta-stimulated A549 cells without affecting COX-2 expression, showing the relative potency of gamma-tocotrienol approximately delta-tocopherol > gamma-tocopherol >> alpha- or beta-tocopherol.

Identification and quantitation of novel vitamin E metabolites, sulfated long-chain carboxychromanols, in human A549 cells and in rats.

The metabolism of vitamin E involves oxidation of the phytyl chain to generate the terminal metabolite 7,8-dimethyl-2-(beta-carboxyethyl)-6-hydroxychroman (CEHC) via intermediate formation of 13'-hydroxychromanol and long-chain carboxychromanols. Conjugated (including sulfated) metabolites were reported previously but were limited to CEHCs. Here, using electrospray and inductively coupled plasma mass spectrometry, we discovered that gamma-tocopherol (gamma-T) and delta-T were metabolized to sulfated 9'-, 11'-, and 13'-carboxychromanol (9'S, 11'S, and 13'S) in human A549 cells.

Electrochemical study of solvent extraction with 8-quinolinols as complexing agent-I. Distribution behavior of 8-quinolinols.

The distribution behavior of 8-quinolinols (HQ) in organic and acidic aqueous solutions (or alkaline solutions) was electrochemically examined by current scan polarography and chronopotentiometry. It follows from the results that the half wave potential of the observed polarographic waves, corresponding to the Faradaic transfer of quinolinolium ions (or oxinate ions) formed in the aqueous solution after distribution of quinolinols is dependent on the dissociation constant of H(2)Q(+) (or HQ) and the pH of the aqueous solution, but independent of the distribution constant of 8-quinolinols.

Electrochemical study of the mechanism of lanthanide extraction with thenoyltrifluoroacetone.

Current-scan polarography at the ascending-water electrode (AWE) was used to examine the electrochemical behavior of HTTA and La(3+), both in the absence and presence of neutral ligands, TOPO or MBDPO, and the light this sheds on the mechanism of extraction of lanthanides with HTTA, as well as the role played by mixed-ligand chelate formation.

The use of brilliant green in ion-pair chromatography.

Brilliant Green is used as the stationary phase in the ion-pair chromatography of butanoic, pentanoic, octanoic and lauric acids, with hexane-dichloromethane as eluent.

Formation constants of Cd(II) complexes with dithizone and related compounds.

The stability constants of cadmium complexes of compounds related to dithizone are reported. Substitution in the ortho position lowers the stability constant. It is probable that this is a consequence of deviation from coplanarity of the phenyl and chelate rings.

Sulphonated azo-dyes as extractive metallochromic reagents.

A survey has been made of analytically useful extractable ion-pair complexes that are formed by the use of a series of metallochromic indicator-metal complexes in conjunction with quaternary ammonium ions. The reagents were o,o'-dihydroxyazo dyes and azo-oxines.

Crystal and molecular structure of zinc dithizonate.

The structure of zinc(II) dithizonate has been determined by X-ray analysis. The co-ordination round the zinc is slightly distorted tetrahedral and the proximal phenyl rings have been shown to be almost coplanar with the chelate rings.

Analytical applications of mixed ligand extraction equilibria Nickel-ditbizone-phenanthroline complex.

The mixed ligand nickel-dithizone-phenanthroline complex provides a sensitive method for determination of nickel and also permits evaluation of the extraction constant for nickel dithizonate. The value log K(ex) = -0.7 was obtained, in agreement with a value of -0.

Reactions of 2',7'-bis(acetoxymercuri)- fluorescein with certain complexing anions.

Absorption and fluorescence emission spectra of 2',7'-bis (acetoxymercuri)-fluorescein (AMF) at various pH values and in the presence of mercury-complexing agents such as mercaptoacetic acid, cyanide and iodide have been employed in the study of the reactions of AMF with these ligands. The findings have been applied to the development of methods for the determination of submicrogram quantities of iodide and cyanide with a precision of better than 10%.

Determination of 2,3-dimercaptopropanol-l (BAL) by titration with zinc, with eriochrome black T as indicator.

A method is proposed for the titrimetric determination of BAL with zinc solution and Eriochrome Black T (EBT) as indicator. It is based on the difference of the stabilities of the Zn(BAL)a and Zn-EBT complexes. The accuracy of the method is very good and the interference of diverse mercaptans is limited to those compounds forming zinc complexes more stable than the Zn-EBT complex.