[Stimulation of regenerative processes and correction of the functional activity of the liver in its partial resection and toxic lesions]. / Stimuliatsiia protsessov regeneratsii i korrektsiia funktsional'noi aktivnosti pecheni pri ee chastichnoi rezektsii i toksicheskikh porazheniiakh.

The effects of hepatotropic growth factors (HGFs) and phospholipid drugs on the recovery of functions and the regeneration of the rat liver were studied in CC14-induced toxic damage and after partial hepatectomy (PHE). HGFs isolated from the cytoplasmic cells of the regenerating liver, as well as from the liver of the animals given prodigiozan and from the media taken after culturing the explants of the regenerating liver were found to stimulate DNA synthesis and hepatocytic proliferation following PHE and in the cirrhotic liver. Prodigiozan was shown to induce the formation of HGFs not only in the rat liver following PHE, but in the liver of intact animals. It was established that the covalently binding complex of albumin and bilirubin stimulated the synthesis of proteins and DNA in the regenerating liver, but non-covalently binding complex inhibited these processes. When CC14 was administered to the animals, the two complexes enhanced the reparative synthesis of DNA, without changing the level of replicating synthesis, the non-covalently binding complex completely eliminating the single-strand breaks in DNA. Phospholipid agents containing soybean and sunflower phosphatidylcholines increased the synthesis of RNA and albumin, which were decreased due to exposure to CC14 and had the property of stimulating the synthesis of total DNA and considerably enhancing that of mitochondrial DNA.

[The effect of phosphatidylcholine on repair processes in liver cells in acute CCl4 damage]. / Vliiane fosfatidilkhonlina na reparatsionnye protsessy v kletkakh pecheni pri ee ostrom povrezhdenii CCL4.

Effect of phosphatidylcholine, isolated from soy beans and sunflower seeds for laboratory use, on synthesis of RNA, DNA, albumin and content of newly synthesized mRNA in polyribosomes was studied in hepatocytes after chemical hepatectomy produced by single administration of CCl4 into rats; histological and histochemical studies of liver tissue were also carried out. Phosphatidylcholine from these plants was found to prevent hepatocyte dystrophy and necrosis development, to activate the macrophage response and to stimulate reparation inducing synthesis and secretion of the tumor necrosis factor. The rate of highly labelled RNA synthesis, mainly mRNA, decreased in liver tissue of rats treated with CCl4, was increased approximately 2-fold after the phospholipid administration. The phospholipid from soy beans restored the albumin synthesis as well as the content of newly synthesized mRNA in rat polyribosomes, while phosphatidylcholine from sunflower seeds restored effectively the mitochondrial DNA synthesis. Promising application of these phosphatidylcholines as hepatoprotectors is discussed.

[Preparation and use of an affinity sorbent containing phenylboric acid, for separation and quantitative determination of glycated hemoglobin]. / Poluchenie i ispol'zovanie afinnogo sorbenta, soderzhashchego fenilbornuiu kislotu, dlia razdeleniia i kolichestvennogo opredeleniia glikirovannogo gemoglobina.

m-Aminophenylboric acid, attached to epoxy-activated diasorb, developed a highly effective sorbent intended to separation and quantitative estimation of glycated hemoglobin. The procedure developed is reproducible, fast and may be used in mass scale examination of people for occult diabetes. Temperature and pH of buffers used did not affect significantly the data obtained.

[Behavior of ketoamine in animals]. / Povedenie ketoamina v organizme zhivotnogo.

A simple ketoamine 14C-fructosoglycine with all the fructose carbon atoms labelled was synthesized for studies of possible pathways of the ketoamines metabolism in animal body. The ketoamine bond in the fructosoglycine was not hydrolyzed during incubation with homogenates of rabbit liver, kidney, spleen and testicular tissues within 3 hrs at pH 4.8 and 7.3 as well as after hydrolysis with pancreatine (the enzymatic extract from bovine pancreas) at pH 8.4. 14C-fructosoglycine administered into rabbit circulation was mainly excreted with urine (about 70% of the label) within 8-14 days. The main part of the ketoamine was excreted as fructosoglycine and the lower amount--as glycated dipeptide; some amount of fructosoglycine was hydrolyzed liberating fructose or converted into aldimine which was hydrolyzed with formation of glucose. The ketoamine was metabolized also into non-reducing isosucrose-like glucofructoside, insensitive to acid and enzymatic hydrolysis.

[The effect of sorbitol on the determination of keto amines using a colorimetric method]. / Vliianie sorbita na opredelenie ketoaminov kolorimetricheskim metodom.

The presence of sorbitol in a concentration 11 mg/ml in a sample reduces by 68 percent the values of fructose glycine measured by colorimetry with thiobarbituric acid. Such sorbitol concentration has no effect on furfural production and on 5-hydroxymethylfurfural reaction with thiobarbituric acid. Measurements of glycolyzed hemoglobin have demonstrated that sorbitol in concentration 11 mg/ml completely inhibits hydrolysis. This fact should be borne in mind when measuring blood glycosylated hemoglobin by colorimetry with thiobarbituric acid and exclude sorbitol from patients' rations before measurements.

[The effect of cholesterol esterase on low density lipoproteins. The effect of modified lipoproteins on the accumulation of cholesterol in cultured cells]. / Deistvie kholesterolésterazy na lipoproteidy nizkoi plotnosti. Vliianie modifitsirovannykh lipoproeidov na nakoplenie kholesterina v kul'turovannykh kletkakh.

Up to 5% of cholesterol esters were hydrolyzed after incubation of blood serum low density lipoproteins (LDL) with pancreatic cholesterol esterase free of proteinases and phospholipase activity in absence of detergents. The surface layer of the lipoprotein particles appears to contain about 5% of cholesterol esters. More active intracellular accumulation of cholesterol esters was found in fibroblasts cultivated in a medium containing modified LDL as compared with cultivation in presence of native LDL. Deterioration of normal interrelations between free cholesterol and its esters appears to be responsible for alterations in the LDL structure and contributed to more active transport of cholesterol into cells.

[Isolation and various properties of immobilized cholesterol esterase]. / Poluchenie i nekotorye svoistva immobilizovannoi kholesterolésterazy.

Immobilization of cholesterol esterase enabled to study the enzymatic modification of blood serum lipoproteins during their interaction with cells. Due to high affinity of octyl-Sepharose to cholesterol esterase large volumes of diluted enzyme preparations were immobilized without preliminary concentration. After immobilization the enzyme pH optimum was unaltered, whereas the activating effect of low NaCl concentrations and inhibitory effect of the salt high concentrations were not observed. The immobilized on octyl-Sepharose cholesterol esterase exhibited the greater stability as compared with the enzyme diluted preparation and was used repeatedly without distinct decrease in activity.

[The type of interaction of macrophages with serum low-density lipoproteins partially hydrolyzed by pepsin]. / Kharakter vzaimodeistviia makrofagov s syvorotochnymi lipoproteidami nizkoi plotnosti, chastichno gidrolizirovannymi pepsinom.

Effect of partial proteolysis of 125I-low density lipoproteins (LDL) from blood serum on their interaction with a culture of mice peritoneal macrophages was studied. Absorption and degradation of the LDL by macrophages was distinctly increased after 10% hydrolysis with pepsin. Degradation of 125I-LDL, hydrolyzed partially by pepsin, in the cells was less inhibited by unlabelled native LDL as compared with unlabelled but modified with pepsin LDL. Macrophages appear to contain specific sites for binding of LDL hydrolyzed partially by pepsin; these sites were distinct from receptors for acetylated LDL as shown by competitive analysis.

[Effect of the proteolysis of low-density serum lipoproteins on their interaction with macrophages]. / Vliianie proteoliza syvorotochnykh lipoproteidov nizkoi plotnosti na ikh vzaimodeistvie s makrofagami.

125I-labelled human serum low density lipoproteins (LDL) were incubated with cultured mouse peritoneal macrophages at 37 degrees C, with the following study of cellular uptake and 125I-LDL degradation by measuring the content of TCA-soluble products of LDL hydrolysis in the cultural medium. It was shown that limited pepsin proteolysis of LDL (10%) led to a more effective LDL uptake and degradation by macrophages. The data suggest that enzyme-induced modification of LDL may increase their atherogenicity.

[Isolation and various properties of cholesterol esterase from swine liver]. / Vydelenie i nekotorye svoistva kholesterolésterazy iz pecheni svin'i.

Neutral cholesterol esterase from cytosol of porcine liver tissue was isolated by means of ion-exchange chromatography on DEAE- and CM cellulose and gel filtration on Sepharose 6B. Specific activity of the isolated cholesterol esterase using cholesteryl-14C-oleate as substrate was 61.2 nmole/mg/hr. Total activity of the enzyme was increased during ion-exchange chromatography as a result of removing of possible inhibitors or endogenic lipids. The enzyme was separated by means of gel filtration on Sepharose 6B into 3 active forms with molecular masses, approximately 200,000, 60,000 and 30,000 daltons. Cholesterol esterase from porcine liver tissue was distinct from the pancreatic enzyme by its ability to hydrolyze substrate in absence of bile acids.

[Isolation of purified aspergillopepsin A]. / Poluchenie ochishchennogo aspergillopepsina A

Two methods of isolation of pure aspergillopepsin A have been developed. The first method is based on sequential chromatography of a crude preparation on gramicidin C-sepharose 4B and ECTEOLA-cellulose (35% yield, 100-fold purification). The second method consists in sequential chromatography of evaporated extract of Asp. awamori surface culture on Acrylex P-10, aminosilochrome and ECTEOLA-cellulose (40% yield, 430-fold purification). The methods discussed may be used to isolate pure aspergillopepsin A preparations in order to establish the primary structure of the enzyme.