PubMed Health⌕ Search

Biomedical subjects

L E Panin

Publications and source records attributed to L E Panin.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Activation of nucleolar DNA and ribosome biosynthesis in hepatocytes under the effect of glucocorticoids and high density lipoproteins].

The structural bases of cooperative effect of glucocorticoids and HDL brings about the activation of protein biosynthesis in hepatocytes. Using surviving rat liver it was shown that these two compounds together activate the gene expression which was indicated by increased 3H-uridine incorporation into the total RNA pool. The enhanced incorporation of 14C-leucine into proteins in these experiments confirms protein biosynthesis acceleration. With the use of liver perfusion technique it was morphologically demonstrated that the earliest changes in hepatocyte genome take place in nucleoli. The increase of nucleolar dimensions and granular component reflects the activation of ribosomal precursors synthesis. Considerable number of ribosomes in the hepatocyte perinuclear space indicates their active transport across the numerous nuclear membrane pores into the cytoplasm. In the first place and more prominently in hepatocytes the protein synthesis "for export" is stimulated, which was proved by the dynamics of ribosome accumulation on the membranes of endoplasmic reticulum according the perfusion duration. The kupffer cells play a significant role in HDL transcytosis and in the realization of their cooperative effect with glucocorticoids.

Animals↗
PubMed2000

[Lipid metabolism, features of nutrition and risk factors of ischemic heart disease in cohorts of Canadian Inuits and Taimyr Nganasans].

Lipids metabolism and blood lipid profiles in native populations of Northern Asia (Nganasans, n = 43) and Northern Canada (Inuits, n = 151) have been studied. Estimation of serum PUFA of omega-6 and omega-3 series in Nganasans testifies to shifting of their diet to "western" type. Three types of dietary patterns have been observed in inuits: traditional one (among age group of 40-69), "western" (among age group of 18-29) and intermediate, transitional (among age group of 30-39). Age differences in concentrations of total cholesterol, summarized fraction of low density and very low density lipoproteins in Nganasans and Inuits were similar, however, Inuits had higher levels of blood lipids including HDL-cholesterol. Concentrations of apoB lipoproteins were significantly higher in Inuits, however, apoA-1/apoB ratios were estimated as more than 1.0 in both groups and the differences were not significant. Correlation between fatty acid composition and lipid profiles in Inuits who followed traditional diet testify to non-atherogenic type of nutrition. Despite to favorable blood lipid profiles in Northern native population, hypercholesterolemia was found in 2% of Nganasans and 10% of Inuits, while hypo-alpha-cholesterolemia was found in 25% Nganasans and in 5% of Inuits. Thus, changes in dietary patterns of native populations of the Far North have a great influence on blood concentrations of PUFAs of omega-3 series. Changes in the dietary fatty acid composition are considered to be one of the possible reasons of dislipoproteinemia.

Adolescent↗
PubMed1999

[Effect of long-term cold exposure on apoprotein A-I, B, and E levels in the rat serum].

An increase in the quantity of triglyceride-rich VLDL as well as the total fraction VLDL and LDL occurred following the cold adaptation. The contents of apoB and apoE, respectively, increased. However, a 5-15-day exposure to cold decreased the LDL2 and apoA-1 content. In 49 days of the experiment, the LDL2 and apoA-1 content was restored.

Adaptation, Physiological↗
PubMed1999

Gadolinium chloride-induced Kupffer cell blockade increases uptake of oxidized low-density lipoproteins by rat heart and aorta.

Oxidized low-density lipoproteins (LDL) play a key role in the formation of atherosclerotic lesions of arteries. We analyzed the effect of hepatic resident macrophage (Kupffer cell) blockade on oxidized [125I]LDL accumulation in different organs and tissues of the rat. Kupffer cell blockade was induced by gadolinium chloride (GdCl3) which was injected intravenously 24 h prior to injection of oxidized [125I]LDL into the rats. Ten minutes after administration to intact animals, oxidized [125I]LDL was accumulated in the liver (86.8% of the dose administered), muscles (4.7%), spleen (2.1%), lungs (0.8%), kidney (0.6%), adrenal glands (0.2%), heart (0.15%), and thymus (0.04%). Kupffer cell blockade significantly decreased the clearance rate of oxidized [125I]LDL from the blood. Specific radioactivity (per g tissue) decreased in the liver (1.3-fold compared to control), but increased in the aorta (2.5-fold), heart (2-fold), lungs (1.6-fold), and kidney (1.3-fold). The results indicate that the accumulation of oxidized LDL in heart and aorta significantly depends on the functional state of the mononuclear phagocyte system in the liver.

Animals↗
PubMed1998

Determination of the fraction composition of blood lipoproteins by the small-angle X-ray scattering technique.

A new method for analyzing the fraction composition of blood lipoproteins (LP) was developed based on the small-angle X-ray scattering (SAXS) technique. The method allows quantitative determination of the contents of basic LP fractions (high-density LP, low-density LP, very low-density LP and their subfractions) in the blood plasma or serum. The results of LP analysis by the new method were compared with electron microscopy, ultracentrifugation and gel electrophoresis data. The results obtained by SAXS correlated with those obtained by traditional methods. The new method for the determination of the LP fraction composition in the blood is rapid (1-1.5 h), uses only one reagent (e.g., sucrose) and features a high accuracy and resolution up to LP subfractions. A total of 0.05 ml of the blood plasma or serum is required for an assay. The assays can be carried out in purified preparations or in the blood plasma or serum. The method developed can be used in clinical practice for diagnostics and in scientific research.

Chemistry, Clinical↗
PubMed1998

[New method for diagnosis of lipid metabolic disturbances].

A new analytical procedure for determining the fraction composition (FC) of lipoproteins (LP) is developed on the basis of the physical method small-angle X-ray scattering (SAXS). This method quantitatively determines the levels of the basic fractions of LP and their subfractions in plasma or serum to analyze LP FC and to diagnose lipid metabolic disturbances. The results obtained by this procedure were compared with those of gel-electrophoresis, biochemistry, and medical diagnosis. There was a good agreement of SAXS and routine methods. The new procedure shows extremely rapid (1.0-1.5 hr) analysis, uses a single reagent (such as the saccharose type), has a high accuracy, and resolution. The analysis requires as high as 0.05 ml of plasma or serum. LP FC may be analyzed both in protein-free and whole native plasma and sera. The findings may be used in clinical care for diagnosis of dyslipidemias and for researches.

Adult↗
PubMed1998

Distribution of tocopherol and apolipoprotein A-I immunoreactivity in rat liver chromatin.

[125I]Labelled lipoproteins (HDL, LDL, and VLDL) are actively taken up by the rat liver. The uptake rate in nonparenchymal liver cells was significantly higher than that in hepatocytes. Analysis of the distribution of the labelled lipoproteins in liver subcellular structures showed the presence of these compounds in the nuclei. The presence of apoA-I, apoB and apoE immunoreactivity in liver cell nuclei was demonstrated by immunochemical methods (ELISA and dot immunoassay). The nuclear matrix and transcriptionally active chromatin displayed the highest apoA-I levels, which considerably exceeded those in the total and transcriptionally inactive chromatins. A similar distribution pattern was observed for alpha-tocopherol. It is concluded that blood serum lipoproteins, primarily HDL, may transport tocopherol and other lipids into cell nuclei.

Animals↗
PubMed1998

[Estimation of physiological nutrient and energy requirements for children of North Asian regions].

In this article it is given an analysis of dependence of the physical development, health and adaptional processes by the children of the North according to the structure of their nutrition. In accordance with the results of this analysis the standards of nutrition and daily food sets are worked out for the children at the age of 6-17 years living on the Asiatic North. Principal difference of recommendations of the Biochemistrycal Institute is that they take in account the features of physical development and metabolism of the children's organism on the North.

Adolescent↗
PubMed1997

[Evaluation of modern child nutrition in boarding schools in Taimyr].

The given reference includes an information about a nourishment, an average daily nutrient and energetic content of foodstuffs in the menu of students in boarding schools on Tajmir. It is determined that there is a disbalance of the main components and the fatty acid, mineral, vitamin contents in the menu of the children of all the ages. The nourishment of the children living in the condition of the Far North has been demonstrated to need correcting.

Adolescent↗
PubMed1997

[Synthesis of insulin fragments and study of their physicochemical and immunological properties].

A two-chain peptide was predicted as a receptor binding site of insulin on the basis of theoretical conformational analysis. This dimeric peptide, consisting of the C-terminal A18-A21 tetrapeptide of the insulin A-chain and the C-terminal B17-B30 tetradecapeptide of the insulin B-chain connected with a disulfide bridge, was synthesized along with the C-terminal nonadecapeptide. The analysis of the aggregation state of human insulin and the synthesized linear and dimeric peptides was performed by the small-angle X-ray scattering method. Specific antibodies were produced after rabbit immunization with the dimeric peptide-BSA conjugate. The immunochemical identity of the model dimeric peptide and the corresponding fragment of the insulin molecule were shown by immunoenzyme analysis.

Amino Acid Sequence↗
PubMed1996

[Effect of plasma lipoproteins and apolipoprotein A-I on lipopolysaccharide-induced production of reactive oxygen metabolites by Kupffer cells of the rat].

The effects of plasma lipoproteins on LPS-induced production of reactive oxygen intermediates (ROI) in Kupffer cells isolated from livers of zymosan-treated rats, have been studied. ROI production was low in normal Kupffer cells but increased 18-fold by LPS in Kupffer cells from zymosan-treated rats. However, preincubation of LPS with rat serum, low density lipoproteins, high density lipoproteins (HDL3) and apolipoprotein A-I (apoA-I) decreased the LPS-induced production of ROI by 1.2-, 1.3-, 2.8-, and 1.5-fold, respectively. In contrast, very low density lipoproteins and HDL2 had no significant effect on the LPS-induced production of ROI. These results provide evidence for LPS-HDL3 complex formation and suggest that HDL3 and apoA-I play an important role in host defense against endotoxemia and infection.

Animals↗
PubMed1996

[The role of the cells of the hepatic sinusoid in regulating protein biosynthesis in hepatocytes].

The protein synthesis in hepatocytes has been shown to be regulated by nonparenchymal (sinusoidal) liver cells. The rate of 14C-leucine incorporation into hepatic proteins and serum proteins was increased during in vivo stimulation of Kupffer cells by lipopolysaccharide (LPS) from Serratia marcescens. Similar results were obtained during a simultaneous cultivation of hepatocytes with nonparenchymal cells, and after the cultivation of hepatocytes in a conditioned medium containing nonparenchymal cells treated with LPS, high density lipoprotein (HDL) and hydrocortisone. The induction of protein synthesis in hepatocytes is presumably associated with the cooperative action of HDL and glucocorticoids.

Animals↗