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6α- and 6β-Hemisuccinoxy derivatives of cortisol, 11-desoxycortisol, 21-desoxycortisol and 21-desoxycortisone were synthesized. The intermediate 6-hydroxy derivatives were prepared by the auto-oxidation of 3,5-dienol 3-alkyl ethers. During this step the dihydroxyacetone side-chain of cortisol and 11-desoxycortisol was protected by the 17,21-acetonide. Following hemisuccinylation the acetonide was removed with acetic acid. The selective synthesis of 3-O-(carboxymethyl)-oximes of cortisol and 11-desoxycortisol is described.  相似文献   

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The enzymes effecting the hydroxylation of steroids in bovine adrenal cortex mitochondria were isolated and their interaction and functioning studied. The results indicated that the sensitivity to ionic strength of the functioning of the hydroxylases studied may be the result of an effect on the transfer of electrons by the iron-sulphur protein, adrenodoxin, and adrenodoxin reductase to cytochrome P450.  相似文献   

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Corticosteroid binder IB, present in liver and kidney, is pronounced in liver cytosol after injection of [3H]triamcinolone acetonide. Following injection of the radioactive ligand, livers homogenized in the presence of 20 mm molybdate, 2 mm leupeptin hemisulfate, 2 mm antipain, or 2 mm phenylmethylsufonyl fluoride produce cytosols with Chromatographie profiles of binders II and IB identical to controls, as determined by DEAE-Sephadex chromatography, suggesting that IB is a cellular constituent rather than a product of protease action (sensitive to the above inhibitors) after cell breakage. Generation of IB in kidney cytosols in vitro appears to be unrelated to protease activity. Liver binder IB has an S value of 5–6 and a Stokes radius of about 26 Å producing a calculated range of molecular weight from 40,000 to 50,000 with frictional coefficient and axial ratio close to spherical values. As expected of a steroid receptor, IB, like II, binds to DNA and to liver cell nuclei but IB binds more tightly as evidenced by the fact that KCl is more effective in eluting II than IB from nuclei. Because recovery of bound radioactivity from acceptors is sometimes difficult to achieve, indirect experiments have been used frequently to determine the binding. Pyridoxal phosphate extracts liver IB and II equally from nuclei but spermidine is ineffective. While IB and II can be extracted partially from nuclei by pancreatic DNase I, more binder II is extracted by this method than IB. Micrococcal nuclease is poorly effective in either case. Binder II is extracted to a greater degree from DNA-cellulose than is IB by spermidine, MgCl2, pyridoxal phosphate, and NaCl. IB binds more extensively to homodeoxypolymers than II. The extent of binding of liver IB to homodeoxypolymers is in the order: poly(dC) ≥ poly(dG) > poly(dA) ? poly(dT), whereas the order for liver binder II is: poly(dG) ≥ poly(dT) > poly(dC) ? poly(dA). Binders IB and II may be separate gene products or IB may arise in the cell from post-translational action. In the latter case, the activity of a protease cannot be ruled out.  相似文献   

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In order to study the preservation of ischemic tissue, an in vivo end-artery model was designed using the rabbit ear. Ear surface-area necrosis and ear edema were quantitatively evaluated for 14 postoperative days in a total of 107 rabbits. The LD50 of ischemic injury was determined by effecting 8, 10, and 12 hours of circulatory arrest. Using a 12-hour ischemic interval in this model, methylprednisolone decreased edema formation (p less than 0.01) and dramatically halted the progression of ischemic injury to necrosis (p less than 0.05) when administered within 5 hours after the onset of ischemia and continued for 3 postoperative days. A single perioperative dose of methylprednisolone was ineffective in decreasing edema formation and preserving tissue. Administration of steroids greater than 5 hours after the onset of ischemia was similarly ineffective even when administered for 3 postoperative days.  相似文献   

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Therapy with systemic corticosteroids, despite attendant serious risks, is mandatory in diseases such as pemphigus, acute disseminated lupus erythematosus and some cases of exfoliative dermatitis that are ordinarily fatal, for in such cases life may be prolonged and the patients made comfortable. If no contraindications exist, therapy with corticosteroids is desirable, for diseases of short duration-contact dermatitis, serum sickness reactions and drug eruptions of all kinds-provided the causative factors have been removed and the reactions are causing severe distress.On the basis of encouraging reports in the literature corticosteroid therapy may be instituted with justification for a group of unrelated, intractable and discomforting diseases such as maddening pruritus ani, sclerema neonatorum, dermatomyositis, certain cases of sarcoidosis, berylliosis, Behcet's syndrome, universal calcinosis, Reiter's disease and ulcers of sickle-cell anemia. One must always bear in mind the well-defined contraindications to corticosteroid therapy and the hazards of its use, particularly if therapy is to be prolonged. Results from topical hydrocortisone therapy are particularly pleasing in chronic eczematous otitis externa and especially when it is combined with an antibiotic drug. Results are excellent also in nuchal eczema, dermatitis of the eyelids and in pruritus ani. More often than not, hydrocortisone ointment and lotions benefit more than do other standard remedies such diseases as atopic eczema, contact dermatitis, lichen simplex-chronicus and eczematized phases of conditions such as psoriasis and superficial mycotic infections. Preparations containing a combination of hydrocortisone and an antibiotic are more useful than hydrocortisone alone. When used with discrimination, with full attention to the selection of cases and proper concentration in the correct vehicle, hydrocortisone preparations in combination with antibiotics are excellent antieczematous agents.  相似文献   

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