Steroid vitamins

The common name vitamin D is used throughout the pharmaceutical kidustry for simplicity. The trivial name calciferol has also been used extensively with the prefix ergo- and chole-, which kidicate vitamin D2 (2) and vitamin (4), respectively (see Steroids). Vitamin D2 was originally named calciferol in 1931 by Angus and co-wotkets (2). Historically, a number of substances were referred to as vitamin D and were distinguished from one another by a subscript numeral, eg, vitamin D2, vitamin D, etc. 

In the case of carbohydrates blue chromatogram zones are produced on a yellow background that slowly fades [2]. Steroids, vitamins, antioxidants, phenols and aromatic amines yield, sometimes even at room temperature, variously colored chromatogram zones [5]. -Blockers and laxatives also acquire various colors [7, 10]. The detection hmits are in the nanogram to microgram range [5]. 

Erythromycin is extracted by an organic solvent such as pentyl acetate. Similarly, steroids, vitamin B12, morphine and codeine are extracted with organic solvents. 

Signals that enter the cell (steroids, vitamin D, thyroid hormone, and retinoids)... 

Several biologic ligands are sufficiently lipid-soluble to cross the plasma membrane and act on intracellular receptors. One class of such ligands includes steroids (corticosteroids, mineralocorticoids, sex steroids, vitamin D), and thyroid hormone,... 

Three hormones serve as the principal regulators of calcium and phosphate homeostasis parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23), and the steroid vitamin D (Figure 42-2). Vitamin D is a prohormone rather than a true hormone, because it must be further metabolized to gain biologic activity. PTH stimulates the production of the active metabolite of vitamin D, l,25(OH)2D. l,25(OH)2D, on the other hand, suppresses the production of PTH. l,25(OH)2D stimulates the intestinal absorption of calcium and phosphate. l,25(OH)2D and PTH promote both bone formation and resorption in part by stimulating the proliferation and differentiation of osteoblasts and osteoclasts. Both... 

Mammals have several classes of hormones, distinguishable by their chemical structures and their modes of action (Table 23-1). Peptide, amine, and eicosanoid hormones act from outside the target cell via surface receptors. Steroid, vitamin D, retinoid, and thyroid hormones enter the cell and act through nuclear receptors. Nitric oxide also enters the cell, but activates a cytosolic enzyme, guanylyl cyclase (see Fig. 12-10). 

Steroid, vitamin D, retinoid, and thyroid hormones enter target cells and alter gene expression by interacting with specific nuclear receptors. 

Reversed-phase chromatography is the most popular mode for the separation of low molecular weight (<3000), neutral species that are soluble in water or other polar solvents. It is widely used in the pharmaceutical industry for separation of species such as steroids, vitamins, and /3-blockers. It is also used in other areas for example, in clinical laboratories for analysis of catecholamines, in the chemical industry for analysis of polymer additives, in the environmental arena for analysis of pesticides and herbicides, and in the food and beverage industry for analysis of carbohydrates, sweeteners, and food additives. 

Vitamin A (retinol) improves the humoral and cellular tolerance of a person who suffers from an infection. By affecting the differentiation of cells and regulating the metabolism of steroids, vitamin A stimulates the activity of macrophages and T-cytotoxic lymphocytes. It also raises secretion of cytokines and production of antibodies (Hughes 1999, Pfahl and Chytil 1996). 

UPS results are also available for the amino acids and their methyl esters, peptides, porphyrins, steroids, vitamins, opiate narcotics, biogenic amines, tranquilizers, antipyretic and antiinflammatory agents, quinonoid molecules (which are important for electron... 

Fermentation [16]. Some important pharmaceuticals, including steroids, antibiotics, and certain food additives (such as vitamins) are produced by fermentation. In fermentation, microorganisms (e.g., bacteria, yeast, or fungi) are inoculated in a liquid broth supplemented with nutrients (e.g., temperature, pH, oxygen). These microorganisms produce the desired product (e.g., antibiotic, steroid, vitamin, and so on) as a by-product of normal metabolism. The process of fermentation includes three steps ... 

Nucleosides, nucleotides, pestiddes, phenols, purine derivatives, steroids, vitamins... 

International Union of Pure and Applied Chemistry, /. Am. Chem. Soc. 82, 5575-84 (I960) Definitive rules for the nomenclature of amino acids, steroids, vitamins, and carotenoids (lUPAC). 

Cholecalciferol is metabolized to produce other steroidal vitamins/hormones. How and in which tissues does this occiu ... 

Fluorescence detection is often used where no other property of the solute (e.g. UV of RI detection) is convenient and can be either an intrinsic property of the solute itself or a derivatised form of the solute. Solution studies have indicated that the sensitivity of detection can be increased by up to three orders of magnitude over UV. This has increased the popularity of post-column fluorescence detection methods for may compounds, including physiological fluids, catecholamines, and other polyamines. A popular use of fluorescence detection is in peptide chemistry where no convenient intrinsic chro-mophore is present. Derivatising agents such as orthophthalaldehyde and fluorescamine are used extensively in both pre- and post-column systems allowing detection of low picomole quantities (Chapter 11). In addition, detection can be performed using the intrinsic fluorescence of many compounds such as steroids, vitamins, and nucleotides. 

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