[Physiological and biochemical in vivo study of polyphenols and 20-hydroxyecdisone from quinoa grains effect on resistance to physical exercise in Wistar rats].

Increasing the ability of the human body to adapt to physical stress is relevant from the standpoint of using foods for special uses containing functional food ingredients (FFI) with effectiveness proven in vivo. The purpose of this study was to evaluate the effect of FFI from Chenopodium quinoa grains with a high content of polyphenols and phytoecdysteroids on the physical endurance of male Wistar rats. Material and methods. The experiment was carried out during 36 days using 50 weaned male Wistar rats. The animals were randomly divided into 3 groups (n=12): Control, Run and Run-FFI. Rats of the Control and Run groups received a standard semisynthetic diet during the experiment. Rats of the Run-FFI group received a semi-synthetic diet with the addition of FFI in an amount of 0.055±0.003%, containing phytoecdysteroids (50.4±0.6 mg/g) and polyphenols (212.0±2.0 mg/g). During the experiment, the rats were assessed for their neuromotor function (grip strength of front paws), memory, and behavioral reactions in the "Elevated Plus Maze" (EPM), "Conditioned Passive Avoidance Reflex" (CPAR) and "Open Field" (OF) tests. Once a week, animals from the Run and Run-FFI groups were subjected to moderate physical load on a "Treadmill". On the 36th day of the experiment, the animals of these groups were subjected to exhausting physical load. Immediately after running, the animals were placed in metabolic cages to collect daily urine. At the end of the experiment, the content of corticosterone, the activity of catalase, indicators of protein, lipid and mineral metabolism, indexes of the liver functional state and antioxidant defense system parameters were analyzed in the blood serum; the level of prostaglandin E2 and dopamine were determined in daily urine. Results. Physiological tests (CRAR, OF) showed that weekly exercise increased anxiety in laboratory animals. The FFI introduction into the diet led to normalization of the assessed parameters (EPM). As a result of 36-day consumption of FFI against the background of physical loads, a significant decrease by 22% in the main stress marker, corticosterone, was revealed in the blood of rats, as well as significant increase by 23% in the stress inhibitor - prostaglandin E2 urinary excretion, compared with animals of the Run group to the level not differed from the indicators of the control animals. There were no differences in endurance performance between the Run and Run-FFI groups on the results of the exhaustive exercise. Consumption of FFI prevented the formation of excess ammonia, significantly reducing the level of urea in the blood and normalizing its excretion to control levels in the urine, which was increased in the Run group by 19%. Conclusion. The results obtained demonstrated the adaptogenic properties of the developed FFI in response to stress caused by weekly moderate and acute exhaustive physical activity. The obtained data on the biological effect of the developed FPI on the adaptive potential of laboratory animals will serve as an experimental basis for its inclusion in the composition of specialized foods.

[Innovative methods for extracting biolactive сompounds from plant materials].

Modern methods for extracting bioactive сompounds (BAC) from various raw materials are focused on efficacy and environmental awareness, involve the use of mathematical and statistical optimization methods, the choice of green solvents, and the use of additive extraction technology. The aim of this review was to present and briefly discuss up-to-date information on modern technological approaches to the production of plant BAС extracts for applying in food ingredients and foods for special dietary uses. Material and methods. For the main search of sources, the PubMed bibliographic database, Scopus and Web of Science databases, and the Google Scholar search engine were used. The search depth was 15 years. Results. The article presents a brief review of modern approaches to the extraction, concentration and purification of polyphenolic compounds from various plant materials. As an additive extraction technology aimed at destroying/increasing the permeability of the plant cell wall, a wide range of physical methods has been successfully used: ultrasound, microwave radiation, homogenization, application of a pulsed electric field, high hydrostatic pressure, cryo-crushing. A brief description of each method, its advantages and disadvantages are presented. Improving food safety and compliance with environmental regulations requires the choice of a safe, environmentally friendly and yet efficient extraction process. For these purposes enzymatic extraction, environmentally friendly solvents, such as deep eutectic solvents, supercritical fluid extraction and membrane technology are successfully used. The use of mathematical and statistical methods can reduce the total number of experimental trials and reduce the cost and time of experiments. The use of these methods together makes it possible to vary deliberately the process parameters in relation to a specific plant material and the final product, which provides the opportunity to isolate BAS concentrates from plant raw materials with a high yield. Conclusion. The introduction of innovative technological approaches for obtaining extracts of BAC of plant origin determines the prospects for the production of a wide range of foods for special dietary uses that meet high safety and efficiency requirements.

[Physiological and biochemical evaluation of the effectiveness of a new food ingredient - blueberry polyphenol concentrate].

Extracts from bilberry leaves and blueberries containing a wide range of biologically active compounds, including polyphenols, are of particular interest due to their antioxidant, hypoglycemic and hypolipidemic properties. In this regard, The aim of this research was to investigate in vivo the effect of a concentrate of blueberrie polyphenolic compounds with buckwheat flour on some physiological and biochemical parameters in C57Bl/6 mice with impaired carbohydrate and lipid metabolism induced by the consumption of a high fat high carbohydrate (HFHC) diet. Material and methods. The polyphenol concentrate was obtained by sorption of blueberry extract on grinded buckwheat flour. Total polyphenol content was determined by Folin-Ciocalteu method, profiles of anthocyanins, flavonoids and easily digested carbohydrates were determined by HPLC. An in vivo experiment was carried out using 84 male mice C57Bl/6 for 109 days. Animals were divided into 3 groups: control fed standard semisynthetic diet, control treated with HFHC diet and experimental group treated with HFHC diet with addition of blueberry polyphenol concentrate (60 mg-eq. of gallic acid/kg body weight). Food intake, body weight gain and fasting blood glucose levels were measured during the experiment. Grip strength of the front paws of the animals was measured weekly. Oral glucose tolerance and insulin resistance tests were carried out twice. Common physiological tests (Elevated Plus Maze and Passive Avoidance Test) were used to assess the anxiety and memory of animals. Glycated hemoglobin level was determined in blood, plasma was collected for leptin and insulin level determination. The hepatic levels of triglycerides and cholesterol were assessed. Results. The concentrate of polyphenols extracted from blueberries and sorbed on grinded buckwheat flour was obtained under conditions that made it possible to exclude the sorption of easily digested carbohydrates - glucose, fructose and sucrose on the flour. The total concentrate content of polyphenols was 65.5±0.7 mg-eq. gallic acid/g, anthocyanins - 27.3±2.7 mg/g, flavonoids - 1.2±0.1 mg/g. The consumption of the concentrate by C57Bl/6 male mice with carbohydrate and lipid metabolism disorders induced by a HFHC diet had a significant (p<0.05) hypoglycemic and hypolipidemic effect, reducing the area under the curve in the insulin resistance test by 5.7% and decreasing the insulin and leptin levels by 31.3 and 15.9%, respectively (relative to the animals of comparison group fed HFHC diet). The consumption of the concentrate had a significant (p<0.05) anxiolytic effect, reducing the anxiety of animals by 2.2 times, as determined in the Elevated Plus Maze test. Conclusion. The results of the study indicate the prospects for using the developed blueberry polyphenol concentrate adsorbed on buckwheat flour as part of specialized foods for the prevention of such alimentary dependent diseases as metabolic syndrome, obesity, and diabetes mellitus.

[Physiological and biochemical studies as a necessary component of the algorithm for assessing the effectiveness of food minor biologically active substances].

Preclinical physiological and biochemical studies of the effectiveness of the tested biologically active substances in the conditions of simulated pathology in laboratory animals are an important stage preceding the assessment of the clinical effectiveness of the created specialized foods for therapeutic or preventive nutrition. The aim of this work is a brief review of the developed algorithm for preclinical assessment of the effectiveness of specialized foods, which includes a set of sequential stages of testing the safety, stability, bioavailability and effectiveness of biologically active substances in experiments on laboratory animals. Results. The paper presents a brief review of methodological approaches for in vivo preclinical assessment of the effectiveness of minor plant biologically active substances - polyphenols from bilberry fruits and leaves and phytoecdysteroids extracted from spinach. A beneficial effect of bilberry leaves' polyphenols on carbohydrate and lipid metabolism of male Zucker and Wistar rats was shown, which determined the necessity to increase the effectiveness of the developed polyphenolic ingredient by sorption on a food carrier. When evaluating the in vivo effects of polyphenols from blueberries and leaves sorbed on buckwheat flour, a pronounced hypoglycemic effect was found. The experiments aimed to the assessment of the adaptogenic effects of phytoecdysteroids from spinach leaves showed a significant decrease in the content of the main biomarkers of the stress system, which indicates a «smoothing¼ of the response of the animal organism to a strong stress impact. Conclusion. The inclusion of minor biologically active substances into the composition of foods for preventive and therapeutic nutrition is the necessary condition to improve their effectiveness. The scientific and practical significance of the preclinical evaluation to a decisive extent depends on the presence of a correctly selected biomodel. Thus, the adequacy of the assessment of the effects of minor biologically active substances as functional food ingredients in the composition of the specialized food products depends on the reproducibility of pathological processes (clinical, biochemical and morphological disorders) characteristic for the studied disease on the selected in vivo model.

[Spinach and quinoa - prospective food sources of biologically active substances].

Formally, phytoadaptogens extracted mainly from medicinal plants are not food substances, and their use in preventive nutrition is significantly limited. However, screening studies can detect phytoadaptogens in food plants, however in much smaller quantities. For example, phytoecdysteroids are biologically active substances (BAS), used to relieve chronic fatigue syndrome, reduce nervous and muscle fatigue, improve memory and attention processes. Phytoecdysteroids can be isolated not only from various medicinal plants, but also from food plants like spinach (Spinacia oleracea) and quinoa (Chenopodium quinoa). Researchers show interest in possible synergies in the manifestation of a wide range of pharmacological effects, determined by a combination of phytoecdysteroids and other biologically active substances of these food plants. The aim of this research is a brief analytical review of publications characterizing the spectrum of minor biologically active substances of spinach and quinoa, as well as those devoted to the experimental assessment of their pharmacological activity in experiments on laboratory animals. Results. An analysis of the publications presented in the review indicates that spinach and its extracts are promising food sources of phytoadaptogens, carotenoids, phenolic compounds, in particular quercetin, kempferol, phenolic acids (p-coumaric, ferulic), as well as lignans metabolized into biologically active phytoestrogens (enterolactone and enterodiol). The possible prophylactic effect of spinach is being actively studied in vivo in laboratory animals when modeling diseases such as diabetes mellitus, cardiovascular and cancer diseases. Numerous adaptogenic effects and the neuroprotective effect of spinach and its extracts are shown, expressed in improving the memory and learning of animals. Publications of the last decade indicate an increased interest in such a promising food source of high-grade protein and a wide spectrum of biologically active substances, including phytoecdysteroids, as quinoa grains. More than 20 phenolic compounds in free or conjugated forms were found in quinoa grains; tannins, saponins, sterols, phytic acid, and ecdysteroids are present in small quantities. The consumptionof quinoa can have a beneficial effect on the organism, normalizing carbohydrate and lipid metabolism, reducing body weight and preventing excessive lipid peroxidation. The anti-inflammatory effects and antioxidant effects of quinoa are widely discussed. Conclusion. Spinach, quinoa and their extracts are promising food sources of biologically active substances, their pharmacological action is confirmed from the standpoint of evidence-based medicine by in vivo experimental studies. Accordingly, it is advisable to expand the use of these food plants for inclusion in biologically active dietary supplements, functional food ingredients and specialized food products for various purposes.

[The impact of bilberry fruits polyphenols, sorbed on buckwheat flour, on the induced disorders of carbohydrate metabolism of male C57BL/6c mice].

The hypoglycemic properties of polyphenolic compounds of plant origin are confirmed by the results of numerous preclinical and clinical studies. However, the biological effects of these compounds are limited by their low bioavailability. This makes it urgent to develop methods for its increasing due to new methods of entering polyphenols into the organism, for example, by extracting them from natural sources in the form of extracts and concentrating extracts on food polymer matrices for subsequent use as a functional food ingredient (FFI). The aim of this study was to evaluate in vivo the possible effect of consumption of the obtained FFI in the form of a food matrix - buckwheat flour enriched with bilberry polyphenols - on carbohydrate metabolism disorders induced by a high-fat diet with a high content of easily digestible carbohydrates (sucrose) and anxiety level of male C57Bl/6c mice. Material and methods. The food matrix was obtained by sorption of the bilberry fruits polyphenol extract on buckwheat flour. The total polyphenol content in the composition of food matrix was 8.9±0.7 mg-eq gallic acid/g flour. Total anthocyanin content in the composition of food matrix was 4.6±0.1 mg/g flour. The experiment was conducted for 150 days using 48 male C57Bl/6c mice (weaners). The animals were divided into 3 groups: the control group K1 (n=16, the mice received a standard semi-synthetic diet (22.5% protein, 10% fat, 58% carbohydrates as starch, 362 kcal/100 g), the control group K2 (n=14) and the experimental group G3 (n=18). Disorders of carbohydrate and lipid metabolism in animals of groups K2 and G3 were modeled by feeding an iso-nitrogenous high-fat diet with a high content of easily digestible carbohydrates (HFHC-diet: 22.5% protein, 30% fat, 18% carbohydrates in the form of starch, 20% sucrose, 493 kcal/100 g). FFI, a food matrix in the amount of 6.6 g/100 g of feed, was introduced into the diet of animals of the experimental group G3, which corresponded to the amount of polyphenols equal to 58.7 mg-eq gallic acid/100 g of feed and the content of anthocyanins 30.4 mg/100 g of feed. Once every three weeks, the level of glucose in the blood of animals was monitored. On days 60 and 114 of the experiment, animals were tested on an elevated plus maze. Animals were decapitated under light ether anesthesia at the end of experiment. The content of glycated hemoglobin was determined in the blood. Results and discussion. Animals of both groups treated with HFHC-diet consumed significantly less feed compared with animals of the control group K1 (2.91±0.05 g/day per mouse). Moreover, animals of the experimental group G3 consumed significantly more food (2.51±0.04 g/day per mouse) compared with animals of the control group K2 (2.36±0.04 g/day per mouse). In contrast, the energy consumption of animals of both groups fed HFHC-diet was significantly higher compared to the K1 group (10.5±0.2 kcal/ day per mouse). Energy consumption by animals of group G3 (12.3±0.2 kcal/day per mouse) was significantly higher compared to animals of the control group K2 (11.5±0.2 kcal/day per mouse). The data obtained indicate that the consumption of FFI in the form of polyphenols adsorbed on the food matrix can contribute to increased appetite in animals treated with the high-fat diet. The results of the Elevated Plus Maze test indicated the absence of the effect of polyphenols in the composition of the food matrix on the anxiety level of animals. Starting from day 42 until the end of the experiment, the glucose level in animals of group G3 was significantly lower than the corresponding indicator for animals of the control group K2. Conclusion. In accordance with the results obtained, further studies of the safety and clinical efficacy of including the developed FFI in the form of a food matrix with polyphenols into the composition of specialized foods for the prevention of carbohydrate metabolism disorders are advisable.

[The complex of bilberry polyphenols, sorbed on the buckwheat flour as a functional food ingredient].

Blueberries, which contain a wide range of polyphenolic compounds, are used in traditional medicine for prevention and treatment of carbohydrate metabolism disorders. However, the high content of mono- and disaccharides in the juice significantly reduces the possibility of using in preventive nutrition by persons with impaired carbohydrate metabolism. In this regard, it is necessary to search for technological approaches aimed at obtaining functional food ingredients with a higher content of polyphenols and a low content of mono- and disaccharides, for subsequent inclusion in corresponding therapeutic foods. The aim of this study was to develop a technological approach to obtain a food matrix by enriching buckwheat flour with polyphenolic compounds extracted from blueberries. Material and methods. The work presents a method for producing a food matrix by sorption of polyphenolic compounds from an aqueous-alcoholic extract of blueberries on buckwheat flour. The concentration of total polyphenols and anthocyanins in the extract and their content in the food matrix was determined by spectrophotometric methods. The content of mono- and disaccharides and profile of individual anthocyanins was determined by HPLC. Results and discussion. The sorption on buckwheat flour was 45% of the total polyphenol content and 48% of anthocyanin content in the initial blueberry fruit extract. The profile of anthocyanins sorbed on a food matrix did not differ significantly from the profile of blueberry extract. The results of determining the content of mono- and disaccharides indicate the absence of their sorption from the extract of blueberries on buckwheat flour. Conclusion. The results obtained are of significant interest, indicating that the sorption approach allows targeted concentration of polyphenols in the food matrix with a minimum amount of easily digestible carbohydrates, which significantly increases the efficiency of its use as a functional food ingredient in dietetic products for people with carbohydrate metabolism disorders.

[The impact of bilberry leaves' polyphenols on the anxiety level, spatial learning and memory of db/db mice].

Numerous experimental and clinical studies have shown high efficiency of plant polyphenolic compounds in restoring age-related memory and learning disorders. In the present study a functional food ingredient (FFI) was obtained by sorption of an aqueous solution of bilberry leaves extract on buckwheat flour, which allowed to concentrate polyphenols and increase their storage stability. The aim of this study was to evaluate the impact of a developed FFI, enriched with bilberry leaves` polyphenols, on the anxiety level, locomotor activity, memory and spatial learning of db/db mice with genetical type 2 diabetes. Material and methods. The experiment was conducted using 10 heterozygote male db/db mice and 10 homozygote male db/+ mice as the comparison control group (7 weeks of age). According to body weight, blood glucose level, the results of insulin resistance test and elevated plus-maze (EPM) test, animals were randomized into three groups: control group C1 - db/+ animals, control group C2 and experimental group G3 - obese db/db mice. Buckwheat flour was included into the diet of C2 group in a dose 22.5 g/100 g; FFI was included into the diet of G3 group in a dose 2.5 g/100 g (that was equal to 59.2± 1.4 mg-eq gallic acid per 100 g of the diet). The anxiety level and general locomotor activity were evaluated in the EPM test. The evaluation of behavior, memory and spatial learning was performed using passive avoidance test (PAT). Glycated hemoglobin level was determined in blood, insulin and leptin levels were determined in blood plasma, general antioxidant activity was determined in liver cytosolic fraction. Results and discussion. The obtained data on biochemical parameters and insulin resistance tests showed the absence of normalizing effects of developed FFI. However, the inclusion of polyphenol-containing FFI into the diet led to beneficial changes in physiological parameters. Animals of G3 group, provided with FFI, were significantly less anxious compared to both control groups. During PAT testing of short-term memory, no animals in G3 group entered to the dark compartment (0%), what demonstrated increased learning ability and well-established memory of these animals in comparison with C1 (50%) and C2 groups (80%). Conclusion. The results prove the effectiveness of bilberry leaves` polyphenols, sorbed on the brown buckwheat flour, in the correction of central nervous system disorders in db/ db mice with genetically altered type 2 diabetes, what points at possible prospect of FFI inclusion in therapeutic products for patients with type 2 diabetes mellitus.

[The experimental evaluation in vivo of hypoglycemic properties of functional food ingredient - polyphenolic food matrix].

The aim of this study was the evaluation of hypoglycemic action of functional food ingredient (FFI) - a polyphenol food matrix in 3-month in vivo experiment with the use of fat male mice C57BL/6. The food matrix was produced by means of incubation of bilberry leaves extract (2% solution, pH 3.6) with buckwheat flour in ratio 1:50 during 45 min at 25 °C. The polyphenol content in experimental batch of matrix was 26.6±0.5 mg-equivalent of gallic acid per 1 g of flour. The experiment was conducted with the use of 46 male mice C57Bl/6c. Blood glucose level was estimated before starting the feeding experiment. An oral fasting glucose tolerance test (GTT) was also conducted, the area under the curve (AUC) was calculated. The animals were randomly divided into 4 groups (according to the body weight, glucose level and AUC): control group K1, fed with standard semisynthetic diet, control group K2 (n=10) and experimental groups G3 and G4 (n=13). The symptoms of type 2 diabetes in groups K2, G3 and G4 were modeled with the use of high-fat high-carbohydrate diet (HFHC diet, 30% fat, 20% sucrose). FFI was included into the diet of animals of experimental groups G3 and G4 in doses 2.5 and 5 g per 100 g of ration, respectively. The GTT test was repeated on the 40th and 82nd days of experiment. On the 15th, 54th and 91st days the insulin resistance test (IRT) was conducted. The consumption of HFHC diet by K2 group animals resulted in development of obesity in these animals to the week 11, which was characterized by increase in the body weight gain (37.1±4.9%) in comparison with control group K1 animals (23.4±2.2%). The introduction of FFI into animal's diet decreased significantly body weight gain of these animals in comparison with K2 group. On the week 8, the significant increase in blood glucose level of animals fed with HFHC diet was found (K2 - 8.2±0.3, G3 - 8.1±0.3, G4 - 8.5±0.3 mmol/L), in comparison with control group K1 (7.1±0.3 mmol/L). On the 91st day of experiment this difference remained significant only for group K2 (9.3±0.6 against K1 group - 7.7±0.3 mmol/L), what shows the beneficial hypoglycemic action of the FFI in both doses (for G3 group - 8.5±0.2, for G4 - 8.4±0.3 mmol/L). On the week 8 the disorder in glucose tolerance was found in animals of group K2, what is one of type 2 diabetes symptoms. The introduction of FFI in a dose 2.5 g/100 g into group G3 diet inhibited the development of these disease symptoms. The introduction of FFI in a higher dose (5 g/100 g of a diet) to a certain extent inhibited the development of insulin resistance. There was no effect of FFI, introduced into animal's diet, on cognitive functions and short-term and long-term memory.

The genomic sequence analysis of the left and right species-specific terminal region of a cowpox virus strain reveals unique sequences and a cluster of intact ORFs for immunomodulatory and host range proteins.

Sequencing and computer analysis of the left (52,283 bp) and right (49,649 bp) variable DNA regions of the cowpox virus strain GRI-90 (CPV-GRI) has revealed 51 and 37 potential open reading frames (ORFs), respectively. Comparison of the structure-function organization of these DNA regions of CPV-GRI with those previously published for corresponding regions of genomes of vaccinia virus, strains Copenhagen (VAC-COP) and Western Reserve (VAC-WR); and variola major virus, strains India-1967 (VAR-IND), Bangladesh-1975 (VAR-BSH); and alastrim variola minor virus, strain Garcia-1966 (VAR-GAR), was performed. Within the left terminal region under study, an extended DNA sequence (14,171 bp), unique to CPV, has been found. Within the right region of the CPV-GRI genome two segments, which are unique to CPV DNA (1579 and 3585 bp) have been found. Numerous differences have been revealed in the genetic structure of CPV-GRI DNA regions, homologous to fragments of the genomes of the above-mentioned orthopoxvirus strains. A cluster of ORFs with structural similarity ot immunomodulatory and host range function of other poxviruses have also been detected. A comparison of the sequences of ORF B, crmA, crmB, crmC, IMP, and CHO hr genes of CPV Brighton strain (CPV-BRI) with the corresponding genes in strain GRI-90 have revealed an identity at the amino acid level ranging from 82 to 96% between the two strains. The findings are significant in light of the recent demonstration of CPV as an important poxvirus model system to probe the precise in vivo role(s) of the unique virally encoded immunomodulatory proteins. Also, the presence of a complete and intact repertoire of immunomodulatory proteins, ring canal proteins family, and host range genes indicates that CPV may have been the most ancient of all studied orthopoxviruses.

Interaction of the phage T4 Dam DNA-[N6-adenine] methyltransferase with oligonucleotides containing native or modified (defective) recognition sites.

The DNA-[N 6-adenine]-methyltransferase (Dam MTase) of phage T4 catalyzes methyl group transfer from S-adenosyl-l-methionine (AdoMet) to the N6-position of adenine in the palindromic sequence, GATC. We have used a gel shift assay to monitor complex formation between T4 Dam and various synthetic duplex oligonucleotides, either native or modified/defective. The results are summarized as follows. (i) T4 Dam bound with approximately 100-fold higher affinity to a 20mer specific (GATC-containing) duplex containing the canonical palindromic methylation sequence, GATC, than to a non-specific duplex containing another palindrome, GTAC. (ii) Compared with the unmethylated duplex, the hemimethylated 20mer specific duplex had a slightly increased ( approximately 2-fold) ability to form complexes with T4 Dam. (iii) No stable complex was formed with a synthetic 12mer specific (GATC-containing) duplex, although T4 Dam can methylate it. This indicates that there is no relation between formation of a catalytically competent 12mer-Dam complex and one stable to gel electrophoresis. (iv) Formation of a stable complex did not require that both strands be contiguous or completely complementary. Absence of a single internucleotide phosphate strongly reduced complex formation only when missing between the T and C residues. This suggests that if T4 Dam makes critical contact(s) with a backbone phosphate(s), then the one between T and C is the only likely candidate. Having only one half of the recognition site intact on one strand was sufficient for stable complex formation provided that the 5'G.C base-pairs be present at both ends of the palindromic, GATC. Since absence of either a G or C abolished T4 Dam binding, we conclude that both strands are recognized by T4 Dam.

[The determination of the genotype of natural reassortant influenza A viruses according to the core protein genes by the methods of competitive dot hybridization and sequencing]. / Opredelenie genotipa prirodnykh reassortantov virusa grippa A po genam vnutrennikh belkov s pomoshch'iu metodov konkurentnoi tochechnoi gibridizatsii i sekvenirovaniia.

Simultaneous circulation of different subtypes of influenza A viruses provides conditions for reassortant strains formation. A comparative investigation of genome of 47 influenza A virus strains (H1N1, H2N2, and H3N2) was carried out by competitive dot hybridization technique and sequence analysis of some of cDNA-copies of the virus genes. All the genes of 43 strains encoding nonglycolysed proteins corresponded to the serum subtype of surface glycoproteins. The reassortant pattern of genome for some genes of core proteins was revealed in 4 viruses. All the dot hybridization data were completely confirmed by sequence analysis of the genes.

[Primary structure of the full-length DNA copy of the influenza virus A/Kiev/59/79 (H1N1) PB2 gene]. / Pervichnaia struktura polnorazmernoi DNK-kopii gena belka PB2 virusa grippa A/Kiev/59/79 (H1N1).

The complete nucleotide sequence of a cloned full-length DNA copy of the A/Kiev/59/79 (H1N1) influenza virus PB2 gene has been determined. This strain is shown to be the natural reassortant which inherited its NP and PB2 genes from the contemporary H3N2 influenza strains.

[Primary structure of the DNA copy of the protein VP1 gene of the foot-and-mouth disease virus A22]. / Pervichnaia struktura DNK-kopii gena belka VP1 virusa iashchura A22.

The DNA-copy of the major antigen (VP1) coding region of the FMDV A22 sero-type has been cloned and sequenced. A comparison of the respective amino acid sequence with those of other VP1 of A-serotype revealed considerable differences in the structure of antigenic determinants.