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Sulfate, activation

Molybdate is also known as an inhibitor of the important enzyme ATP sulfurylase where ATP is adenosine triphosphate, which activates sulfate for participation in biosynthetic pathways (56). The tetrahedral molybdate dianion, MoO , substitutes for the tetrahedral sulfate dianion, SO , and leads to futile cycling of the enzyme and total inhibition of sulfate activation. Molybdate is also a co-effector in the receptor for steroids (qv) in mammalian systems, a biochemical finding that may also have physiological implications (57). [Pg.475]

In general, phase I reactions, such as oxidation and ra-demethylation are delayed in the neonate but are fully operational at or above adult levels by 4-6 months of age in the full-term neonate [27a-30]. Conjugation pathways, such as glucuronidation, do not approach adult values until 3 or 4 years of age. Sulfation activity does appear to reach adult levels in early infancy. For drugs that are subject to metabolism by both pathways, such as acetaminophen, the efficient activity of the sulfation pathway allows infants and children to compensate for low glucuronidation ability... [Pg.668]

Minoxidil (Loniten) is an orally effective vasodilator. It is more potent and longer acting than hydralazine and does not accumulate significantly in patients with renal insufficiency. It depends on in vivo metabolism by hepatic enzymes to produce an active metabolite, minoxidil sulfate. Minoxidil sulfate activates potassium channels, resulting in hyperpolarization of vascular smooth muscle and relaxation of the blood vessel. [Pg.229]

There is much concern about the emissions which result when fuel sulfur combusts (i.e., sulfur oxides). These gaseous products further react to form environmental pollutants such as sulfuric acid and metal sulfates. Active sulfur and certain sulfur compounds can corrode injection systems and contribute to combustion chamber deposits. Under low-temperature operating conditions, moisture can condense within the engine. Sulfur compounds can then combine with water to form corrosive acidic compounds. [Pg.60]

DMSO, Sodium azide, DINA, Methylene chloride. Sodium sulfate. Activated alumina Methyl green. Sodium picramate. Hydrochloric acid. Sodium nitrate... [Pg.136]

Coagulants and coagulant aids iron and aluminum sulfates, activated silicates, alginates, synthetic polyelectrolytes and their impurities, silica, and aluminum electrolyte monomers. [Pg.714]

In the same vein as the cyclic sulfate activation of diols, cyclic sulfamidates have been prepared from 1,2- and 1,3-amino alcohols for the purpose of activating the carbinol toward nucleophilic attack [85-88]. (S)-Prolinol [85], A-benzyl serine t-butyl ester [86], and 2-(2-hy-... [Pg.389]

Denning, M., Kazanietz, M., Blumber, P., and Yuspa, S., Cholesterol sulfate activates multiple protein kinase C isoenzymes and induces granular cell differenation in culture murine keratinoyctes, Cell Growth Differ., 6, 1619, 1995. [Pg.94]

Kawabe, S., Ikuta, T., Ohba, M., Chida, K., Ueda, E., Yamanishi, K., and Kuroki, T., Cholesterol sulfate activates transcription of transglutaminase 1 gene in normal human keratinocytes, J. Invest. Dermatol., Ill, 1098, 1998. [Pg.94]

Figure 2.13. Solubility diagrams showing the pH range for the most stable A1-0H-S04 minerals for a potassium activity of 10-4 M and a sulfate activity of (a) 10 4 M and (b) 10-2 M (from Nordstrom, 1982b, with permission). Figure 2.13. Solubility diagrams showing the pH range for the most stable A1-0H-S04 minerals for a potassium activity of 10-4 M and a sulfate activity of (a) 10 4 M and (b) 10-2 M (from Nordstrom, 1982b, with permission).
Several membrane-bound ATPases occur in the genus Sulfolobus. There are two ATP-hydrolyzing activities in S. acidocaldarius strain 7. One has a pH optimum at 6.5 in the absence of sulfate, and the presence of that anion activates the enzyme and shifts the pH optimum to 5.0. ATP hydrolysis is unaffected by DCCD, azide, NEM, /7-hydroxymercuribenzoate, or vanadate [59]. The other ATPase is most active at pH 2.5, is inhibited by sulfate, and appears to be a pyrophosphatase [16]. The purified sulfate-activated ATPase (M, 360000) is composed of three subunits (Mr 69000, 54000, and 28000). It is most active at 85 C, stimulated some three-fold by sulfate, sulfite, and bicarbonate, but is unaffected by chloride. There are two pH optima. One is located at pH 5 and the other at pH 8.5 and neither is affected by sulfite. ATPase activity is inhibited by nitrate (63% at 20 mM) and NBD-Cl (90% at 1 mM) but is not significantly affected by azide (5mM), vanadate (100 pM), and NEM (100pM)[28]. [Pg.302]

Activation of the latent hydraulic properties of foundry sand can also be achieved with gypsum (sulfate activation). Mixtures of foundry sand with a high aluminum oxide and lime content with ca. 15% calcium sulfate (as raw gypsum or natural anhydrite) are known as supersulfated cement. [Pg.410]

Figure 12.29 Stability fields of phases in the system K -AP -SO -H O at 25°C and I bar pressure, as a function of pH and sulfate activity for K+ = 10" moi/kg. The following p/Tsp values are assumed 33.96 for gibbsite, 88.4 foralunite, 17.8 for jurbanite, and 116 for basaluminite. Dashed lines denote metastable equilibria. The arrows labeled Drying show that the stability field of alunite increases in size with decreasing water activity (drying) at the expense of the jurbanite and gibbsite fields. Figure 12.29 Stability fields of phases in the system K -AP -SO -H O at 25°C and I bar pressure, as a function of pH and sulfate activity for K+ = 10" moi/kg. The following p/Tsp values are assumed 33.96 for gibbsite, 88.4 foralunite, 17.8 for jurbanite, and 116 for basaluminite. Dashed lines denote metastable equilibria. The arrows labeled Drying show that the stability field of alunite increases in size with decreasing water activity (drying) at the expense of the jurbanite and gibbsite fields.
G12. Guyda, H. J., Corvol, M. T., Rappaport, R., and Posner, B. I., Radioreceptor assay for insulin-like peptides in human plasma Growth hormone dependence and correlation with sulfation activity by two bioassays. /. Clin. Endocrinol. Metab. 48, 739-747 (1979). [Pg.104]

Schlumpf, U., Heimann, R., Zapf, J., and Froesch, E. R., Non-suppressible insulin-like activity and sulfation activity in serum extracts of normal subjects, acromegalics and pituitary dwarfs. Acta Endocrinol. (Copenhagen) 81, 28—42 (1976). [Pg.112]

ATP sulfurylase, catalyzes the primary step of intracellular sulfate activation, essential for assimilatory reduction of sulfate to sulfide, involved in methionine metabolism... [Pg.332]

The recovered lead paste is a mixture of the positive (lead dioxide) and negative (lead sulfate) active materials, small metallic fractions from the grid and other materials that have been added to the battery paste such as carbon black, expanders, and reinforcing fibres. A typical range of components in recovered battery paste is given in Table 15.1. [Pg.495]

Ferric iron in solution exists in several forms. The more important forms ass Fe(SO)f. FeSOd+. FE OH), and FeOH2+. The sulfate complexes are greatly favored over the hydroxyl complexes, To illustrate the imponance of iron complex formation, a typical leach solution will be considered in equilibrium with precipitated hydrogen jarosile, having an approximate ftee-sulfate activity of 0.02. The equilibrium is represented by... [Pg.507]

Antineuritic Factor Kinnersly and Peters86 studied methods for concentrating thiamine (torulin) an antineuritic factor present in yeast. In one procedure, neutral lead acetate is added to an aqueous yeast extract to precipitate certain impurities. The filtrate is treated with barium hydroxide to precipitate gums—the excess barium hydroxide being removed with sulfuric acid. Other impurities are removed from the solution with mercuric sulfate. Activated carbon is added to the filtrate to adsorb the active principle which is subsequently extracted with 0.1 N hydrochloric acid in 50% alcohol. [Pg.291]

Minoxidil (loniten) is efficacious in patients with the most severe and drug-resistant forms of hypertension. A small fraction of minoxidil is metabolized by hepatic sulfotransferase to the active molecule, minoxidil N-O sulfate. Minoxidil sulfate activates the ATP-modulated channel in smooth muscle, causing hyperpolarization and relaxation of arteriolar smooth muscle. Minoxidil produces arteriolar vasodilation with essentially no effect on capacitance vessels. Minoxidil preferentially increases blood flow to skin, skeletal muscle, the GI tract, and the heart. The disproportionate increase in blood flow to the heart may have a metabolic basis, in that administration of minoxidil is associated with a reflex increase in myocardial contractility and in cardiac output. The cardiac output can increase by as much as three- to fourfold, primarily due to enhanced venous return to the heart. The increased venous return probably results from enhanced flow in vascular beds with a fast response for venous return to the heart. The adrenergic increase in myocardial contractility contributes to the increased cardiac output, but is not the predominant factor. The renal effects of minoxidil are complex it dilates renal arteries, but systemic hypotension produced by the drug actually can decrease renal blood flow. Renal function usually improves in patients who take minoxidil for the treatment of hypertension, especially if renal dysfunction is secondary to hypertension. Minoxidil potently stimulates renin secretion, an effect mediated by renal sympathetic stimulation. [Pg.557]

Two sulfate complexes of aluminum A1S04 and Al( 804)2" also are reported (I). The same type of computation as that described for fluoride-hydroxide systems was used to prepare Figure 12, showing the predominant species to be expected at various pH s and sulfate activities. [Pg.112]

Figure 12, Predominant form of complex and ratio of free aluminum activity to total dissolved aluminum as a function of pH and sulfate activity... Figure 12, Predominant form of complex and ratio of free aluminum activity to total dissolved aluminum as a function of pH and sulfate activity...
Sulfate-activated TiOa or Zr02 or molecular sieve... [Pg.269]

Ti or Zr salts deposited on silicon dioxide the titanium or zirconium oxide supported on Si02 is sulfate-activated and physically blended with an acidic montmorillonite clay... [Pg.270]

Sulfate-activated Ti02 and Zr02 or a molecular sieve (LZ-Y52, 4A, AW-500, and AW-300) were used in the oligomerization of Cio-20 alkenes. Olefin conversion was 64% and dimer/trimer ratio 5.57, and 86% and 1.80 for sulfated Ti02 and Zr02, respectively. The AW-sulfate activated molecular sieve showed higher activity in comparison with the other molecular sieves. [Pg.274]

Magnesium oxide, y-aluminum oxide, synthetic rutile, thorium dioxide, silica gels, barium sulfate, activated carbons, metallic network supporting structures, various silicates (especially of Mg, Al), etc. [Pg.1611]

Chondroitin sulfates activate ECM-degrading enzymes, such as MMPs, and are therefore involved in the degradation of aggrecan by MMP-2 (30,31), MMP-13... [Pg.210]

Penc SF, Pomahac B, Eriksson E, Detmar M, GaUo RL. Dermatan sulfate activates nuclear factor-kappab and induces endothelial and circulating intercellular adhesion molecule-1. J Clin Invest 1999 103 1329-1335. [Pg.221]


See other pages where Sulfate, activation is mentioned: [Pg.650]    [Pg.222]    [Pg.531]    [Pg.190]    [Pg.178]    [Pg.47]    [Pg.24]    [Pg.644]    [Pg.252]    [Pg.316]    [Pg.11]    [Pg.289]    [Pg.189]    [Pg.270]    [Pg.274]   
See also in sourсe #XX -- [ Pg.189 ]

See also in sourсe #XX -- [ Pg.206 ]

See also in sourсe #XX -- [ Pg.330 , Pg.331 ]




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