Steroids hydrocortisone

The present type of thermosensitive gel has been applied in the immobilization of Arthrobacter simplex cells, and the bioconversion of a steroid (hydrocortisone -> prednisolone by 3-ketosteroid-A1-dehydrogenase in A. simplex) was examined using the thermal cycling method [65]. In this case, the thermal cycling was... 

Steroids (hydrocortisone, prednisolone, betamethasone, adrenosterone, fluocortolone,...)... 

Aminoglutethimide blocks even earlier, preventing the conversion of cholesterol to pregnenolone. It therefore blocks synthesis of aU steroids, hydrocortisone, aldosterone and sex hormones (including the conversion of androgens to oestrogens) it has a use in breast cancer. 

The effects of corticotropin are those of the steroids (hydrocortisone, androgens) liberated by its action on the adrenal cortex. Prolonged heavy dosage causes the clinical picture of Cushing s syndrome. 

The health-care provider has prescribed the topical steroid hydrocortisone for a client experiencing allergic dermatitis. Which instruction should the nurse discuss with the client ... 

The role of the sample matrix is of vital importance. It is quite incorrect to say, for example, that a polarographic method exists for the determination of the steroid, hydrocortisone. One can speak only of a polarographic method for a particular analyte in a specific type... 

The temperature-responsive colunans used for the separation of steroids were produced by grafting pNIPAM to the adsorbent (Kanazawa et al, 1996). At temperatures above the transition point the pNIPAM-modified surface becomes hydrophobic. This provides better separation of the steroid molecules according to their log P values, where P is the partition coefficient of the substance in an octanol/water system. The separation of steroid molecules depends on the hydrophobicity of the stationary phase, which could be regulated by the temperature change. The temperature rise increases hydrophobicity of the modified stationary phase resulting in longer retention times and better separation of steroids according to their hydrophobicity. This is illustrated in Fig. 13.1, which presents elution profiles of five steroids hydrocortisone, prednisolone, dexamethasone, hydrocortisone acetate and testosterone at different temperatures. 

See also rusting, cathodic protection, cortisol See hydrocortisone, cortisone, CjjHjaOs. M.p. 215 C. A steroid. 

This publication provides several examples of the use of solid-phase extractions for separating analytes from their matrices. Some of the examples included are caffeine from coffee, polyaromatic hydrocarbons from water, parabens from cosmetics, chlorinated pesticides from water, and steroids from hydrocortisone creams. Extracted analytes maybe determined quantitatively by gas (GC) or liquid chromatography (LG). 

Hydrocortisone and Prednisolone. Following the discovery of the antiinflammatory actions of cortisone (1) and cortisol (2), there was a need not only to develop highly efficient routes to the corticoids, but to discover novel stmctures with fewer side effects than those of the corticoids, eg, sodium and water retention, reduced carbohydrate tolerance (steroid diabetes), osteoporosis, and depressed host defense. 

Sobering investigators uncovered a second significant breakthrough in microbial biotechnology of steroid production. They discovered that Corynebacterium simplex converted hydrocortisone (cortisol) (29) to prednisolone via a 1,2-dehydrogenation reaction. This A -3-ketosteroid is a highly active antiinflammatory commercial product (162). 

A third advancement in microbial biotechnology of steroid production was the abiUty to introduce a 16a-hydroxyl group microbiologicaHy (163). Modifications of the liP-hydroxylation, 16a-hydroxylation 1,2-dehydrogenation microbial processes are used for the synthesis of hydrocortisone, prednisolone, triamcinolone, and other steroid pharmaceuticals. A few microbial transformations that have been used to manufacture steroids are Hsted in Table 1 (164). 

When in the late 1940 s the remarkable therapeutic effects of the glucocorticoids cortisone and hydrocortisone were discovered, new raw materials had to be developed to produce these complicated molecules, and new synthetic methods devised to convert either a 20-ketopregnane or 21-acetoxy-20-ketopregnane to the dihydroxyacetone side-chain characteristic of these corticoids. This latter challenge produced some extremely useful new organic chemical reactions, many of which have wider application outside of steroids. 

Whole microbial cells as well as microbially derived enzymes have played a significant role in the production of novel antibiotics. The potential of microorganisms as chemical catalysts, however, was first fully realized in the synthesis of industrially important steroids. These reactions have assumed increasing importance following the discovery that certain steroids such as hydrocortisone have anti-inflammatory activity, whilst derivatives of the steroidal sex hormones are nsefiil as oral contraceptive agents. More recently, chiral inversion of non-steroidal anti-inflammatory dmgs (NS AIDs) has been demonstrated. 

APA from penicillin G, 7-ACA from cephalosporin C, 7-ADCA from desaacetoxy cephalosporin G Biotransformation in steroids, e.g. cortexolone to hydrocortisone and prednisolone Food additives Lactic Acid (now a bulk chemical for making polylactate). Citric acid, L-Glutamate, L-Lysine, etc. Vitamines C, B2, B12 Acarbose (antidiabetic drug)... 

Electron impact ionization, also known as particle beam ionization, has been applied to the online determination of steroids such as hydrocortisone, cortisone, prednisolone and prednisone. Polymer additives such as NC-4, Irga-nox 1076,1-octadecanol and Naugard -XL were identified and quantitated online by electron impact and, separately, by atmospheric pressure chemical ionization methods.78... 

A thin layer of hydrocortisone cream (0.25% to 1%) applied twice a day for no more than 2 weeks is an appropriate treatment regimen. The use of higher-potency steroids or use extending beyond 2 weeks should be at the discretion of a physician only. 

The summary of Pe values for the steroids as a function of stirring rates is found in Table 11 and their correlations with log PC (n-octanol-water) in Figure 20. The transport kinetics of the relatively hydrophilic hydrocortisone and dexa-methasone are controlled by passive diffusion across the cell monolayer. On the other hand, the Pe values of testosterone and progesterone are highly dependent on stirring rate. The results for testosterone are used to obtain the relationships between the effective permeability coefficients of the ABL on the donor and receiver sides and the stirring rate, using the linear expression (see Eq. (69)]... 

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