The effects of 6 weeks feeding with diets low in methionine, choline, or proteins on the biotransformation and retention of 76As-labelled arsenite (0.4 mg As/kg bw) in rabbits have been studied. All test diets caused a significant decrease in the urinary excretion of dimethyl[76As]-arsinic acid, the main metabolite of inorganic arsenic. This gave rise to an increased retention of arsenic in the...

myokinase. A disadvantage of the method is the slow hydrolysis of adenosinetriphosphate in the final stages of the reaction. 2. Metallic salts of adenosinetriphosphate are shown to be unstable and break down on storage to adenylic acid and inorganic pyrophospShate, and to a less extent to adenosinediphosphate and inorganic phosphate. 3. The best preparations of adenosinetriphosphate are at leas...

BACKGROUND Sulfiting agents are widely used as food additives. Limits are set on their use in foods because they may adversely affect health. Sulfiting agents are excreted in urine as sulfate, which is indistinguishable from sulfate derived from sulfur amino acids. OBJECTIVE The objective was to assess the contribution of inorganic sulfur to urinary sulfate excretion and of dietary protein to...

The determination of arsenic(III) and arsenic(V), as inorganic arsenite and arsenate, was investigated by CE with capacitively coupled contactless conductivity detection (CE-C(4)D). It was found necessary to determine the two inorganic arsenic species separately employing two different electrolyte systems. Electrolyte solutions consisting of 50 mM CAPS/2 mM L-arginine (Arg) (pH 9.0) and of 45 m...

The leaching kinetics of a low-grade zinc oxide ore in different acid media was investigated with respect to the experimental variables including acid concentration, temperature, liquid to solid (L/S) ratio, and stirring speed. The results obtained showed that the leaching reagent concentration and the reaction temperature exerted significant effects on the extraction of zinc, whereas the L/S r...

Experimentally induced calcification within mitochondria has been studied electron rnicroscopically. Cells investigated comprise hepatic cells damaged by CCl(4) intoxication, myocardial cells damaged by prolonged dihydrotachysterol (DHT) administration, and cells from skeletal muscle (gastrocnemius) damaged by DHT sensibilization and local injury. Cells from a human bowel carcinoma were studied...

In the accompanying paper (2) it was shown that Neisseria meningitidis, strain 1908 (Group C), forms N-acetylneuraminic acid by the condensation of N-acetyl-n-mannosamine and phosphoenolpyruvate with elimination of the phosphate group. In a preliminary communication we have reported a neK type of reaction carried out by another enzyme of Ncisserio meningitidis, strain 1998, which might be consi...

Infant rice cereals were analyzed for total arsenic, inorganic arsenic (i-As) and the organic arsenic species monomethylarsonoic acid (MMA) and dimethylarsinic acid (DMA) using liquid chromatography inductively coupled plasma mass spectrometry (LC-ICP-MS). Total arsenic concentrations in the samples ranged from 110 ng/gup to 420 ng/g. The i-As in the rice cereals accounted for 33% to 77% of the...

Hemoglobin Abruzzo is an abnormal human hemoglobin with a substitution at a residue known to be involved in the binding of 2,3-diphosphoglyceric acid. It has increased oxygen affinity and reduced heme-heme interaction in the absence of organic or inorganic phosphate cofactors. In inorganic phosphate buffers the Bohr effect and heme-heme interaction are normal, but the oxygen affinity remains hi...