Gly cation

Glutathione S-transferases 550, 682 Glycans 169 -180. See also Polysaccharides N-linked 183 Gly cation 169 Glyceraldehyde 163s... 

Wang, X., Desai, K., Clausen, J.T., and Wu, L. 2004. Increased methylglyoxal and advanced gly-cation end products in kidney from spontaneously hypertensive rats. Kidney Int 66 2315-2321. 

However, first both the formation of Amadori compounds and of advanced gly-cation endproducts in vivo must be considered. 

O Brien, R., and Timmins, K. (1994). The role of oxidation and gly cation in the pathogenesis of diabetic atherosclerosis. Trends Eiidocrinoi. Metob, 5, 32 334. 

Evidence of selective oxidative damage, resulting from redox imbalance, involving neurons tied to AD is accumulating. The advanced gly-cation end products, nitration, lipid peroxidation adduction products, carbonyl-modified neurofilament protein, and free carbonyls belong to the list (200). The question remains whether the oxidative damage is caused by A)3, known to possess oxidative and hydrolytic properties (286, 287), or by other factors, whereas Aj3 is released as an antioxidant in response to oxidative stress (200). As in other groups of potential AD therapeutics there is a noticeable difference between their behavior in vitro and in vivo. A number of potential antioxidants are or have been in clinical trials... 

The term immunoreactive insulin is used in reference to assays that may recognize, in addition to insulin, substrates that share antigenic epitopes with insulin. Examples include proinsulin, proinsuHn conversion intermediates, and insulin derivatives, produced by gly-cation or dimerization. 

The elevated serum levels of LDL cholesterol found in patients such as Ivan Applebod who have type 2 diabetes meUitus is multifactorial. One of the mechanisms responsible for this increase involves the presence of chronically elevated levels of glucose in the blood of poorly controlled diabetics. This prolonged h5 perglycemia increases the rate of nonenzy-matic attachment of glucose to various proteins in the body, a process referred to as gly-cation or glycosylation of proteins. 

Peng, X., Cheng, K.W., Ma, J., Chen, B., Ho, C.T., Lo, C., and Wang, M. 2008. Cinnamon bark proanthocyanidins as reactive carbonyl scavengers to prevent the formation of advanced gly-cation endproducts. Journal of Agricultural and Food Chemistry, 56(6), 1907-11. 

Figure 10.15 N on-enzymic gly cation of proteins by high concentrations of glucose in poorly controlled diabetes mellitus.

Water is, of course, a solvent with marked and frequently discussed structural features. The majority of recent work on complex formation kinetics in which water is involved has been concerned with mixed solvents, containing smaller or greater amounts of organic components added to modify the structure of the water, and is therefore referenced in the following section. One reaction in aqueous solution in which solvent structure is thought to be an important factor is that of the exchange of glycine with the [VOH(gly)] + cation. Here there are some deviations from normal kinetic behaviour, which may be ascribed to solvent structural effects. 

Stereoselective cis-dihydroxylation of the more hindered side of cycloalkenes is achieved with silver(I) or copper(II) acetates and iodine in wet acetic acid (Woodward gly-colization J.B. Siddall, 1966 L. Mangoni, 1973 R. Criegee, 1979) or with thallium(III) acetate via organothallium intermediates (E. Glotter, 1976). In these reactions the intermediate dioxolenium cation is supposed to be opened hydrolytically, not by Sn2 reaction. 

In aqueous solutions at pH 7, there is little evidence of complex formation between [MesSnflV)] and Gly. Potentiometric determination of the formation constants for L-Cys, DL-Ala, and L-His with the same cation indicates that L-Cys binds more strongly than other two amino acids (pKi ca. 10,6, or 5, respectively). Equilibrium and spectroscopic studies on L-Cys and its derivatives (S-methyl-cystein (S-Me-Cys), N-Ac-Cys) and the [Et2Sn(IV)] system showed that these ligands coordinate the metal ion via carboxylic O and the thiolic 5 donor atoms in acidic media. In the case of S-Me-Cys, the formation of a protonated complex MLH was also detected, due to the stabilizing effect of additional thioether coordination. ... 

Small ACTH fragments related to ACTH-(4-10) have also been investigated for the presence of ordered structure. CD of ACTH--(5-10) in TFE showed a random structure (50) as was found with H-NMR for fragment 4-10 (51). The addition of anionic or cationic surfactants to an aqueous solution of ACTH-(4-11) dit not promote any a-helix or 3-form in this peptide (CD experiments S2). When ACTH-(1-14) and 1-10 were measured by CD and NMR respectively, indications for a helical or ordered structure were found (90, ). Thus it seems that the addition of the non-helix "prone" fragment 1-3 or 1-4 can promote the formation of a helical structure in the adjacent sequence. Arguments in favour of this come from the theoretical work of Argos and Palau (53) on amino acid distribution in protein secondary structures. They found that Ser and Thr frequently occur at the N-terminal helical position (cf. Ser in ACTH) to provide stability the position adjacent to the helical C-terminus is often occupied by Gly or Pro (adjacent toTrp in ACTH we have Gly ) acidic amino acid residues are frequently found at the helix N-terminus (cf. Glu in ACTH) and/or basic residues at the C-terminus (cf. Arg ). 

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