In commercial preparations

CmC, a preservative in commercial preparations of some intravenous drugs, activates CICR in a way similar to that of caffeine. 4-CmC is more potent than caffeine and shows isoform-dependent activation profiles it is much less effective in RyR3 than RyRl or RyR2. 

PCDFs are similar in many respects to PCDDs but have been less well studied, and will be mentioned only briefly here. Their chemical structure is shown in Figure 7.1. Like PCDDs, they can be formed by the interaction of chlorophenols, and are found in commercial preparations of chlorinated phenols and in products derived from phenols (e.g., 2,4,5-T and related phenoxyalkanoic herbicides). They are also present in commercial polychlorinated biphenyl (PCB) mixtures, and can be formed... 

Recently, Robach et al. ( ) investigated the effects of various concentrations of sodium nitrite and potassium sorbate on N-nitrosamine formation in commercially prepared bacon. 

Sato, M. et al.. Effect of sodium copper chlorophyUin on lipid peroxidation. IX. On the antioxidative components in commercial preparations of sodium copper chlorophyUin, Chem. Pharm. Bull, 34, 2428, 1986. 

Purity levels of commercial preparations have also been estimated based on their Cu contents and compared with the theoretical values expected for fuUy coppered chlorophyllin based on the two major compounds Cu(ll) chlorin e4 (disodium salt) and Cu(ll) chlorin e6 (trisodium salt). The expected theoretical content of copper in a pure Cu chlorophyllin complex is 9.2%, which has never been found in commercial preparations. The sodium copper chlorophyllin from Sigma-Aldrich (St. Louis, MO) has a 4.5% copper content, specified by the manufacturer with respect... 

Analysis of nitrogen contents could be an aid for estimating the chlorophyllin concentration, complementing the copper analysis. The Cu N ratio of 1.1 calculated based on a Cu content of 9.2% and N content of 8.1% must be re-evaluated because both Cu and N levels found in commercial preparations are significantly lower than theoretical values. 

The aim of this chapter is to give a general overview of the methods available for producing "industrial" quantities -i.e. amounts of at least some kilograms- of enantiomerically pure substances which can be used as "active" materials in commercial preparations (pharmaceuticals, drugs or medicines, pesticides, etc.). 

Nutraceuticals are used by the medical profession as part of the treatment of specific conditions. (Many are available in commercial preparations.) They include glutamine, arginine, nucleosides and polyunsaturated fatty acids. The explanation for their benefit is described in Chapter 18. 

Inhibitors of lactic dehydrogenase have been reported in commercial preparations of NAD+ and NADH (B4, M6, S28). The concentration of inhibitory substances varied from lot to lot. In a serum lactic dehydrogenase study with NAD+ from 8 sources, activities were found to vary from 145 to 75 units (B4). Inhibitors of lactic dehydrogenase activity have also been observed in dialyzates in uremic patients (W8) and in human urine (G8). The purity of available substrate can also effect enzyme activity. Schwartz and Bodansky observed that, in 6 batches of fructose 6-phosphate, all weighed to a 0.5 mM concentration, the actual concentration varied from 0.13 mAf to 0.55 mM (S14). 

The pesticide rotenone and five other rotenoids were determined in formulations by using RPC (597, 598). The assay of warfarin in rodenti-cide preparations has been reported by Billings et al. (599). Methiocarb (3,5-dimethyl-4-(methylthio)phenylmethylcarbamate) has been determined in commercial preparations (666). The diaistereomers of sumicidin. 

Williamson BL, Tomlinson AJ, Naylor S, et al. Contaminants in commercial preparations of melatonin [Letter]. Mayo Clin Proc 1997 72 1094-1095. 

Williamson, B. L. Tomlinson, A. I Mishra, P. K. Gleich, G. J. Naylor, S. 1998. Structural characterization of contaminants found in commercial preparations of melatonin similarities to case-related compounds from L-tryptophan associated with eosinophilia-myalgia syndrome. Chem. Res. Toxicol., 11,234-240. 

Currently, about 70 percent of the coal mined east of the Mississippi River is cleaned in commercial preparation plants (27). This includes both metallurgical and steam coal. Although coal cleaning has not traditionally been a means to control SO2 emissions but rather has been a way to control coal quality, it can... 

High concentrations of sodium chloride and azides are used frequently as preservatives in commercial preparations, but these components can reduce antibody reactivity. Excessive ionic strength can decrease specific staining by interfering with antibody-antigen binding. 

Approximately six years ago vanadate was identified as a contaminant in commercially prepared (Sigma) ATP56, that inhibits the sodium- and potassium-stimulated... 

In commercial preparations, several fractions of the dye are always separated since different consumers have quite different requirements as to the appearance of the product. The oxalate of malachite green corresponds to the formula, 2 C2 )H24N2 + 3 CaHi-O. The crystallization requires several days and frequently crystals of great beauty are obtained. The addition of ammonium oxalate to promote crystallization is reminiscent of similar procedures in alkaloid chemistry and was discovered purely empirically. 

Petritis, K. et al. Validation of ion-interaction chromatography analysis of underivatized amino acids in commercial preparation nsing evaporative light seattering detection. Chromatographia 2004, 60, 293-298. 

Bovine trypsin can also be chromatographed on CM-cellulose at pH 3.2 in an ionic strength gradient (115). In this way, active trypsin begins to separate from inactive proteins present in commercial preparations or formed during trypsinogen activation in the absence of calcium. After... 

Polynucleotides. Poly (dG-m dC). poly (dG-m dC). This polynucleotide is available from Pharmacia, Inc., Piscataway, NJ or other biochemical companies. Dissolve the polynucleotide at a concentration of 0.5-1 mg/ mL in 50 mMNaCl buffer. Dialyze the polynucleotide solution with this buffer three times to remove the excess salt and MgClg that are usually present in commercial preparations. 

When employing high specific activity radionuclides, care should be taken to be sure that the iodine atom is in the form of iodide (I ). Oxidized forms of iodine, such as periodate or iodate which commonly occur in commercial preparations, are not incorporated into proteins by the procedures outlined here. 

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