PubMed Health⌕ Search

Biomedical subjects

F A Medvedev

Publications and source records attributed to F A Medvedev.

At least 19 recordsLinked to original sources
PubMed2006

[The influence of diet with including amaranth oil on lipid metabolism in patients with ischemic heart disease and hyperlipoproteidemia].

It was investigated the influence of a diet supplemented with amaranth oil on dynamic of lipid profile and composition of fatty acids of erythrocytes in patients with ischemic heart disease and hyperlipoproteidemia. The efficacy of diet with different contents of squalene (100, 200, 400 and 600 mg per day) was compared. It was shown that antiatherosclerotic diet with including 600 mg squalene has promoted the most positive changes of the serum cholesterol and triglycerides level and fatty acid composition of erythrocytes membranes as well.

Amaranthus↗
PubMed2006

[Amaranths oil: peculiarities of chemical composition and influence on lipid metabolism by rats].

In experiment on rats it was shown a hypocholesterolemic effect of amaranth oil. The decrease of cholesterol lever in rat blood was not accompanied by its increasing in a liver. The turn from a model of hypercholesterolemia to the diet with amaranth oil also prodused decreasing of cholesterol lever in rat plasma and liver as compared with control animals. In the composition of rat liver sterins the increasing of plant sterins was observed that probably was due to squalene presense in amaranth oil.

Amaranthus↗
PubMed1988

[Selective incorporation of polyunsaturated fatty acids of the omega-3 family in the diet into the cerebellar phospholipids of rats].

TLC, GLC and GC-MS methods were applied for studying the fatty acid composition of rat cerebellum phospholipids. 75 male Wistar rats had a diet without fat for 6 weeks and then a diet with linseed oil, fish oil in combination with lard and mixture of sunflower oil with lard (control group) for 3 months; PUFA omega 6/omega 3 rations were 0.27; 0.5 and 45.0. PUFA omega 3 in all fractions were represented mainly by 22:6 omega 3 (0.2-12.0%) acid and its share depends on the total PUFA omega 3 amount in the diet. The absence of 18:3, 20:5 and 22:5 omega 3 in cerebellum lipids, fed in great amount with test diets, suggested that these acids are rapidly desaturated and elongated to 22:6 omega 3 at the blood-brain barrier. Established competitive inhibition of desaturases responsible for the synthesis of tissues PUFA omega 6 and omega 3 proves the expressed regulatory effect of alimentary factor on brain lipids.

Animals↗
PubMedDate not supplied

[Composition of sterols from arthrospores and mycelia of the fungus Mucor hiemalis].

Sterol composition of the arthrospores and mycelium of the fungus Mucor hiemalis 1156 was studied by the method of chromatography-mass spectrometry. Along with ergosterol, the major sterol of the culture studied, ten minor sterol were identified, which were either precursors or products of ergosterol degradation. The content of individual sterols differed substantially in arthrospores and mycelium, which represent different stages of ontogenetic development of the fungus. In arthrospores, the content of ergosterol was lower than in mycelium (55.9 and 78%, respectively). Among the precursors of ergosterol, methylated sterols predominated in arthrospores (24.1% versus 11.6% in mycelium). Eburicol and 4,4-dimethylfecosterol were the major methylated sterols of arthrospores (10.6 and 8.1%, respectively). In addition, two uncommon and extremely rare sterols, 1-dihydro-dehydroneoergosterol and dehydroneoergosterol, were identified (for the first time in M. hiemalis). These substances, containing a complex system of conjugated double bonds in their A and B rings, are the products of ergosterol degradation. The data on sterol composition are discussed in terms of their morphogenetic implication.

Chromatography, Gas↗
PubMedDate not supplied

[The characteristics of lipid ligand binding by serum albumin in athletes].

The ability of serum albumin to bind lipids, fatty acids and products of their peroxidation was studied in well trained sportsmen during a competitive period. Detected quantitative and qualitative alterations point to a protein involvement in metabolic changes in an adaptation to work loads.

Bicycling↗
PubMedDate not supplied

[A method of determining the levels of deoxynivalenol (vomitoxin) and its metabolites].

A method has been developed for assay of deoxynivalenol (DON) and its metabolite desepoxideoxynivalenol (DOM-1) in animal excrements with the use of reversed-phase high-performance liquid chromatography with UV-detection (218 nm). The method includes purification in the mini-column with activated carbon and aluminium oxide. The detection limit was 50 ng/g, relative standard deviation--0.05-0.1, the degree of toxin isolation--76-89%. DON isolated from Fusarium macroceras, strain 579a, cultivated in rice under laboratory conditions, and DOM-1 obtained as a result of DON incubation with the contents of the beef first stomach, were used in the study. The structure of toxins isolated has been proved by the mass-spectrometry method. The method developed by the authors was used in the study of DON metabolism in vivo in monkeys.

Animals↗
PubMedDate not supplied

[Characteristics of the binding by serum albumin of fatty acids and products of their peroxidation during intensive muscular work].

The ability of serum albumin to bind polyunsaturated fatty acids and products of their peroxidation in long-distance cyclists was investigated during their recovery period. In response to high workloads well trained athletes, when compared to lower class cyclists, showed a significant decrease of partial portions of linoleic, arachidonic, eicosapentaenic and other fatty acids. These findings indicate that albumin plays an important part in the transport of fatty acids and lipid peroxidation products as one of biochemical components of metabolic transformations in the course of adaptation to high workloads.

Adaptation, Physiological↗
PubMedDate not supplied

[Transport of fatty acids and products of their peroxidation by serum albumin in ischemic and non-coronary injury of the myocardium].

Functional ability of blood serum albumin to bind lipids, fatty acids and products of their peroxidation was studied in ischemic and non-coronary impairments of myocardium. Certain alterations were detected in the transport volumes of low molecular substances studied, which suggest the important function of albumin in biochemical shifts of bioenergetic and other metabolic reactions during myocardial impairments.

Biological Transport↗
PubMedDate not supplied

[Changes in the sterol content of soybean oil after its thermal processing].

A study was made of alterations in the composition of soybean oil sterols after thermal treatment. It was established that in heat-exposed oils, the content of total sterols dropped 20 to 50%. Analysis of a sample of free sterols from soybean oil heated for 13 h demonstrated a slight decrease in the content of stigmast-5-en-3 beta-ol at the expense of a rise in the concentration of delta 5-avenasterol, citrostadienol, and 24-methylene cycloartanol.

Chromatography, Thin Layer↗
PubMedDate not supplied

[Carbohydrates of the chicken egg yolk].

In the yolk of the eggs of hens receiving traditional feeding hydrocarbon mixtures contained in trace amounts therein were analyzed by a specially elaborated method. For identification and quantification the data of the gas liquid chromatography, chromato-mass-spectrometry and ultraviolet spectrophometry were used. In a complex hydrocarbon mixture chromato-mass-spectrometry helped identify the alkanes of the normal and isoprenoid structure, cycloalkanes, of terpene and sterene types. The alkanes and cycloalkanes fraction content was found to comprise 15-30 per 1 mg of the raw mass of the yolk, of the p-alkanes--1-3 mg, squalene--15-17 mg and of monocyclic arenes--about 1 mg.

Alkanes↗
PubMedDate not supplied

[Method of determining and the makeup of the aliphatic hydrocarbon fractions of sunflower, cottonseed and soya oils and of oil cakes].

To determine the content and composition of aliphatic carbohydrates in vegetable oils and oil cakes a method including alkaline hydrolysis, partition and thin-lower chromatography, gas-liquid chromatography and chromate-mass-spectrometry was devised. The content of n-isoalkans, isoprenoids, monocycloparaffins, bi-and tricyclic naphthenes, steranes and terpenes, olifines, squalene and other polyenes in sunflower, cotton, soya oils and oilcakes was measured.

Chromatography, Gas↗
PubMedDate not supplied

[Accumulation and transformation of dietary ergosterol in rats].

The results of experiments on rats given the ergosterol-containing diet for a long time indicate that ergosterol was incorporated in liver tissues in trace amounts which are not comparable with ergosterol concentrations exerting an effect in model experiments. Ergosterol was not detected in the liver after 3-day experiments. At the same time it was established that the proportion of unchanged ergosterol in rat feces was about 16% of the amount administered per os. The products of a possible ergosterol transformation (dehydroneoergosterol-24-methyl-1,3,5 (10), 6,8 (9), 22-hexaen-3 beta-ol; 24-methylcholesta-7,24 (28)-dien-3 beta-ol; 4-cholesta-7,22,25 (?)-trien-3 beta-ol; 4-methylcholesta-7,22 (?)-dien-3 beta-ol, and so forth were identified in feces.

Animal Feed↗
PubMedDate not supplied

[Determination of the N-nitrosamine content in meat and meat products].

Samples of meat and meat products for the content therein of carcinogenic N-nitrose-amines were subjected to a fluorometric analysis. In case of positive results the presence of NA was confirmed by cromate-mass-spectrometric and/or mass-spectrometric methods. The mean value for the concentrations of dimethyl-nitrose-amine, diethyl-nitrose-amine and nitrose-piperidine in meat products is within the ranges of 1.5-5.4, 1.0-6.1, 0.9-23.4 gamma/kg, respectively. NA was not found in meat.

Animals↗
PubMedDate not supplied

[Effect of storage and handling on the fatty acid composition of the Antarctic krill Euphausia superba].

Gas liquid chromatography and chromato-mass-spectrometry were used to study and compare the fatty acid composition of lipids from the Antarctic krill Euphausia superba shortly after catch and after storage for 6 months in the frozen form or thermally treated and then frozen. Fatty acid lipids were found to contain acids having a methyl group in the 2d position, and acids having an OH group in the 2d and 3d positions, which had not been reported before. The technological treatment did not produce any changes in fatty acid composition which might affect the biological value of the product under consideration.

Animals↗
PubMedDate not supplied

[N-nitrosamines in beer and nonalcoholic beverages].

The content of carcinogenic N-nitrosamines was examined in beer, kvas, kvas wort, in dried pear and drink prepared from the dried fruit. An analysis was made with the use of the fluorescence technique. It was found that only some of the beer grades contain a negligible amount of N-nitrosamines. The remaining products showed no N-nitrosamines.

Beer↗