Proteus mirabilis urease catalyzes the hydrolysis of urea to CO(2) and NH(3), resulting in urinary stone formation in individuals with complicated urinary tract infections. UreR, a member of the AraC family, activates transcription of the genes encoding urease enzyme subunits and accessory proteins, ureDABCEFG, as well as its own transcription in the presence of urea. Based on sequence homology...

The effect of urea as an electrophoretic buffer solution modifier on the ion-association (IA) capillary electrophoresis (CE) separation of four anionic metal complexes of Al(III), Co(III), Cr(III), and Fe(III) with 2,2'-dihydroxyazobenezene-5,5'-disulfonate (DHABS) using a hydrophobic ion-association agent, tetrapentylammonium bromide, was studied. The mutual separation of the four anionic meta...

or,-Cycloserine (5 to 10 mvl), when added to isolated hepatocytes, is shown to inhibit aspartate aminotransferase predominantly in the cytosol. At low concentrations (0.1 to 0.2 mu) it selectively inhibits alanine aminotransferase. Aminooxyacetate (0.5 mu) irreversibly inhibits all transaminase activity provided the inhibitor is added prior to substrate addition. Neither cycloserine nor aminoox...

GOLDSTEIN, LEON, AND KOY P. FORSTER. Osmoregulation and urea metabolism in the little skate Raja erinacea. Am. J. Physiol. 220(3) : 742-746. 197 1 .-Little skates, Raja erinacea, were transferred gradually (4 days) from full to approximately half-strength seawater. Steady-state conditions (with respect to solute and water balance) were established by the end of the dilution program. The skates ...

background: rupture of fetal membranes can occur at any gestational age. premature rupture of membranes (prom) means rupture of fetal membranes before the onset of labor. objective: the purpose of this study was to evaluate and compare the reliability of the vaginal washing fluid urea and creatinine for the diagnosis of prom and to determine cut-off values. materials and methods: a total of 179...

Excess urea fertilizer application to the agricultural fields causes severe environmental deterioration. Researchers actively seek safer alternatives, such as nanoparticles with unique properties, reduce chemical inputs without compromising output. In present study, three variants─hydroxyapatite–urea, magnesium-doped hydroxyapatite–urea, and zinc-doped hydroxyapatite–urea nanohybrids─have been ...

GOLDSTEIN, LEON, AND KOY P. FORSTER. Osmoregulation and urea metabolism in the little skate Raja erinacea. Am. J. Physiol. 220(3) : 742-746. 197 1 .-Little skates, Raja erinacea, were transferred gradually (4 days) from full to approximately half-strength seawater. Steady-state conditions (with respect to solute and water balance) were established by the end of the dilution program. The skates ...

in order to investigate the effects of applying three and five continuous periods of municipal solid waste (msw) with and without npk chemical fertilizer on the amount of micronutrient uptake by different parts of wheat, a pot experiment was conducted in split plot based on randomized complete block design with four replications in 2009. the main plot was a six-fertilizers level including contr...

Nitrogen was recognized over 200 yr ago as an element essential for normal function of farm animals. During the first half of the 19th century, the roles of proteins and urea in N metabolism were discovered. By the middle of the 20th century, the substrates, products, and enzymes of the urea cycle were elucidated. Work since then has quantified dietary crude protein requirements for specific pr...

The vasopressin-regulated urea transporter (UT)-A1 is a transmembrane protein with two glycosylated forms of 97 and 117 kDa; both are derived from a single 88-kDa core protein. However, the precise molecular sites and the function for UT-A1 N-glycosylation are not known. In this study, we compared Madin-Darby canine kidney cells stably expressing wild-type (WT) UT-A1 to Madin-Darby canine kidne...