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Among extra-hepatic manifestations of hepatitis C virus (HCV) infection particular interest is focused on some dermatological diseases such as: leukocytoclastic vasculitis, oral lichen planus, pruritus-urticaria, psoriasis. Aim of this paper is to analyze these typical dermatoses in a population of patients with HCV infection and describe the characteristic clinical pictures. These clinical pictures confirm the importance of liver examination in presence of skin diseases not related to other pathogenetic mechanisms.

A method for the analysis and identification of the principal related substances in 9 alpha-fluoroprednisolone acetate is described. This compound has been chosen as a model for the investigation of related substances which can be originated in the general procedure for introducing a fluorine substituent at position 9 of a corticosteroid molecule. HPLC procedures, both in reversed and in normal phase were used; a rapid scanning UV detector which allows direct spectrophotometric data to be obtained on chromatographic peaks, proved to be a tool of great importance. Thus, after reversed-phase chromatographic separation and observation of the UV spectra and their respective second derivatives, it was possible to characterize some of the principal effective and potential related substances such as 9 alpha-fluorohydrocortisone acetate, 9 alpha-bromoprednisolone acetate, 9 beta, 11 beta-epoxyprednisolone acetate and 9(11)-dehydroprednisolone acetate, emerging as chromatographic peaks. Identification of 9 alpha-bromoprednisolone acetate and of 9 alpha-fluorohydrocortisone acetate which proved to be the most significant impurities, was confirmed by means of an exhaustive study of the mass spectra of these substances conveniently isolated by normal-phase HPLC. The chromatographic, spectrophotometric and mass-spectrometric characteristics of the studied compounds are reported.

Some HPLC procedures with isocratic or gradient elution are reported for the identification and determination of most of the characteristic components of cortical extracts. The proposed solvent systems were: A) for normal phase chromatography, mixtures of chloroform-methanol-water on silica columns. B) For reversed phase chromatography, mixtures of methanol-water or acetonitrile-water or tetrahydrofuran-water on octadecyl silica columns of different brands. With these systems it was possible to identify and determine, in addition to the principal corticosteroids, some minor components of the cortical extracts as the 20β-dihydroderivatives of compounds F, E, A, B, the 17-ketosteroids adrenosterone, 11β-hydroxyandrostendione and androstendione and finally, progesterone and 17-OH progesterone. In reversed phase chromatography it was also possible, by monitoring the effluent at 205 nm, to reveal the 5α- and 5β-tetrahydroderivatives of the main corticosteroids and to separate them from most of the steroidal components of the adrenal extracts; in these conditions it was also possible to reveal some characteristic, unknown components of the cortical extracts. Some results of quantitative analysis of cortical extracts are also reported, comparing different analytical procedures.

A reversed-phase high-performance liquid chromatographic method was developed for the assay of medroxyprogesterone acetate and for the detection and determination of related steroids present as impurities in the drug. The method was compared with the normal-phase technique of the USP XX and was also applied to the analysis of tablets and injectable suspensions.

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In a previous paper a method was described by which sulphuric esters and glucuronides of steroids could be separated by paper electrophoresis and chromatography. This method was applied to the separation and quantitative determination of the 17-ketosteroids present in urinary extracts after they had been converted to the corresponding sulphuric esters. The present paper deals with the application of the above-mentioned technique to the separation and quantitative determination of the conjugated 17-ketosteroids, directly extracted from urine by means of n -butanol. A sample of 200 ml of 24-hour urine is sufficient for the determination; the conjugated 17-ketosteroids are separated from the pigments and fractionated in two zones corresponding to sulphates and glucuronides, respectively.

An oral load of beta-carotene (500 mg) was administered to four normal, four hypo and four hyperthyroid subjects. Plasma beta-carotene content was determined at the 2nd, 4th, 6th, 8th, 10th, 12th and 24th hour after administration and at every 24th hour thereafter for 5 consecutive days. Plasma assays were performed by HPLC. No significant differences were revealed by Student's T test for one group to the other. The authors sustain that, as there is no impairment in intestinal uptake of beta-carotene in disthyroid subjects, the elsewhere described increase in carotinemia in hypothyroids is due to other mechanisms.

The article describes a new method to determine the quantity of mestranol and of norethisterone in a combined oral contraceptive. Gas chromatography was used simultaneously to detect both agents, after they were extracted with ethyl acetate from the total compound of the tablet.

Plasma concentrations of beta-carotene and retinol, determined by HPLC, and of transport proteins, ascertained by immunodiffusion technique, in hypo and hyperthyroid subjects are reported. In hypothyroid subject a considerable increase in carotene was noted. This was not the case for retinol. In hyperthyroids both beta-carotene and retinol levels were found to be normal. Transport protein (PA and RBP) levels were found to be lower only in cases of hyperthyroidism but unchanged for hypothyroids. According to the Authors the results show that the alteration in plasma carotene levels to be found in hypothyroid subjects is not the direct consequence of a lack of thyroid hormone in the metabolism of vitamin A but the indirect effect of thyroid disease.

Ferritin, an iron-containing protein widely diffused in nature, has the important biochemical function of being the principal reserve and regulator for Fe3+ levels in blood and tissue. Due to its natural, effectively non-toxic iron content, ferritin has been the object of strong interest in the development of pharmaceutical products for use in iron deficiency treatment. Therefore, the need has arisen for the analytical characterization of this industrial product, be it in the hydroglyceric solution or dry powder form. The main considerations for the characterization of industrial ferritin are the following: a) iron content in both the unmodified product and the precipitated protein; b) protein content and protein/iron ratio; c) protein identification by means of polyacrylamide gel electrophoresis (PAGE); d) confirmation of protein identity and evaluation of molecular weight by means of size exclusion chromatography; e) identification and evaluation of other components of bulk ferritin preparations such as preservatives, excipients for lyophilization, water and concomitant proteins. Eight different samples were examined using the above considerations. Among the qualitative and quantitative results reported, of particular interest are those obtained by means of size-exclusion high performance liquid chromatography (SEC-HPLC). With a UV "diode array" detector it is possible to discern the peaks for ferritin and its molecular aggregates from those of concomitant proteins and preservatives; furthermore, it is possible to evaluate their molecular dimensions. Using this method, the ferritin monomer and other protein fractions can be quantitatively analyzed either by calculating area percent distribution of the chromatographic peaks or by comparing the sample with a highly pure external standard of ferritin.(ABSTRACT TRUNCATED AT 250 WORDS)

A rapid, simple and specific high performance liquid chromatographic procedure for assaying alpha- and beta-carotene is described. The method also enables the simultaneous determination of retinol and dl-alpha-tocopherol in human serum. The same chromatographic procedure can be used to assay the major carotenoids in human serum, provided analyses are replicated and the effluent is monitored at 450 nm. The conditions described also enable determination of licopene, cryptoxanthine and lutein with zeaxanthine. An aliquot of 0.5 ml serum is deproteinized with ethanol (0.5 ml) and extracted with petroleum ether (0.75 ml). The petroleum ether extract is evaporated until dry and then redissolved immediately with 0.5 ml of an eluent mixture consisting of methanol-hexane (85:15, v/v). Aliquots of 50 microl are then injected onto a 250 x 4.6 mm column packed with Spherisorb ODS-2. Owing to its good reproducibility, the procedure can be used for assays with external standards. Clinical applications are described for cases of hypercarotinemia associated with endocrine dysfunctions such as hypothyroidism and diabetes.

Plasma beta-carotene and retinol assay was performed by high pressure liquid chromatography (HPLC) in subjects with chronic renal failure or liver cirrhosis. In the same subjects blood prealbumin (PA) and retinol binding protein (RBP) were determined by immunological technique. A considerable increase of retinol and in a lesser extent of beta-carotene was noted in the blood of patients with renal insufficiency. In cirrhotic patients it was shown a marked decrease both of beta-carotene and retinol plasma concentrations. PA and RBP there were greatly increased in renal failure and decreased in liver cirrhosis. This results suggest that kidney and liver chronic failure interfere with vitamin A metabolism throughout their action on metabolic processes of synthesis and elimination of PA and RBP.

An experimental procedure is described in order to standardize a gaschromatographic method proposed for a collaborative study organised by the F.I.P. Committee for Laboratories and Official Drug Control Services, on the analysis of some oestro-progestinic formulations. The assayed combination was a standard mixture of lynestrenol, mestranol and d, 1-alpha-tocopherol: testosterone was included as internal standard; two combinations, differing only in the internal standard content as specified in the text, were used. The variability of the instrumental factor was investigated performing some sets of single experiments, each consisting of 5 successive injections of the same standard mixture, on the same day. For each single experiment and for each substance the mean value Rm of the ratios R (R=area of the peak for compound cpi/area of the peak of the internal standard) was estimated with its relative standard deviation (% s.d.). For each set of experiments the % s.d. values were elaborated, following the Bartlett test, in order to obtain the sigma intra % value for each set, as a measure of the instrumental factor. An experimental evidence was observed for the relationship existing between the instrumental factor value (sigma intra %) and the internal standard content, in the operating conditions fixed for the present gas chromatographic analysis, a lowering of the instrumental factor beeing observed with the higher level of testosterone content (internal standard) in the mixture.