[Study of the prevalence of antibodies to some arboviruses in the population of the Republic of Guinea].

INTRODUCTION: Acute febrile diseases kill more than 250,000 people annually in West Africa. Malaria and typhoid fever traditionally occupy most of the total structure of registered fevers. However, these data do not fully reflect the true overall disease patterns in the West African region. This is due to the fact that diagnosis is mainly based on the clinical signs of the infectious process, suggesting that a certain number of diseases may be caused by arboviruses. The detection of specific antibodies (ABs) to infectious pathogens in the blood sera of residents of a particular area is a reliable indicator of the circulation of these pathogens in a particular territory.The aim of this study was to determine the prevalence of antibodies to a number of arboviruses: Dengue (DENV), West Nile (WNV) (family Flaviviridae), Crimean-Congo hemorrhagic fever (orthonairo)virus (CCHFV), Batai (Batai virus), Bhanja (BHAV) (order Bunyavirales), Chikungunya (CHIKV), and Sindbis (SINV) (family Togaviridae) in the population of the Republic of Guinea. MATERIAL AND METHODS: In total, a panel of 2,620 blood serum samples from people living in all landscape and geographical areas of Guinea was collected for the study. Detection of IgG antibodies was performed using an enzyme-linked immunoassay (ELISA). RESULTS: In total, ABs to Batai virus were detected in 144 samples (5.5%), BHAV in 58 (2.2%), WNV in 892 (34.0 %), DENV in 659 (25.2 %), CCHFV in 58 (2.2 %), CHIKV in 339 (12.9 %), and SINV in 52 samples (2.0 %). DISCUSSION: The obtained results indicate serological evidence of the spectrum of arboviruses in the population of all landscape and geographical zones of the Republic of Guinea, confirming their active circulation in this territory. CONCLUSION: Given the high epidemiological significance of arbovirus infectious diseases, it is an urgent task to continue studying its share in the structure of febrile diseases in the territory of the Republic of Guinea.

The Cardio- and Neuroprotective Effects of Corvitin and 2-Oxoglutarate in Rats with Pituitrin-Isoproterenol-Induced Myocardial Damage.

Heart diseases, especially acute coronary syndrome (ACS), are among the most severe illnesses that often lead to death. Despite significant advances in the prevention and treatment of ACS, the incidence of the disease and its complications are very serious. The imbalance between pro- and antioxidant systems, the formation of active carbonyl compounds, and the end products of glycation in the blood and tissues are the key moments in the development of heart and neurological disorders leading to a change of behavioral responses. So, the search for antioxidants with cardio- and neuroprotective effects is an urgent task. This study was aimed at evaluating the effects of Corvitin and 2-oxoglutarate on physiological parameters, heart histology, and markers of carbonyl/oxidative stress of rats with pituitrin-isoproterenol-induced myocardial damage (PIMD). Increased sweating, tachycardia, significantly decreased locomotor and exploratory activity, changes of ECG, heart histology, and biochemical changes were observed in the PIMD-group. The administration of Corvitin or 2-OG led to the recovery of locomotor and cognitive activities of the rats, improvement in heart histology, a decrease in the levels of thiobarbituric acid reactive substances, advanced glycated end products, and various changes in the activity of the antioxidant enzymes, 6 days after PIMD. So, Corvitin and exogenous 2-OG show cardio- and neuroprotective effects through the decrease of carbonyl/oxidative stress and regulation of the activity of the antioxidant system.

Atmospheric nitrogen deposition on petals enhances seed quality of the forest herb Anemone nemorosa.

Elevated atmospheric input of nitrogen (N) is currently affecting plant biodiversity and ecosystem functioning. The growth and survival of numerous plant species is known to respond strongly to N fertilisation. Yet, few studies have assessed the effects of N deposition on seed quality and reproductive performance, which is an important life-history stage of plants. Here we address this knowledge gap by assessing the effects of atmospheric N deposition on seed quality of the ancient forest herb Anemone nemorosa using two complementary approaches. By taking advantage of the wide spatiotemporal variation in N deposition rates in pan-European temperate and boreal forests over 2 years, we detected positive effects of N deposition on the N concentration (percentage N per unit seed mass, increased from 2.8% to 4.1%) and N content (total N mass per seed more than doubled) of A. nemorosa seeds. In a complementary experiment, we applied ammonium nitrate to aboveground plant tissues and the soil surface to determine whether dissolved N sources in precipitation could be incorporated into seeds. Although the addition of N to leaves and the soil surface had no effect, a concentrated N solution applied to petals during anthesis resulted in increased seed mass, seed N concentration and N content. Our results demonstrate that N deposition on the petals enhances bioaccumulation of N in the seeds of A. nemorosa. Enhanced atmospheric inputs of N can thus not only affect growth and population dynamics via root or canopy uptake, but can also influence seed quality and reproduction via intake through the inflorescences.

[Glycoprotein sialylation and NEU1 and ST6GAL1 expressions in erythremia].

We studied the levels of lymphocyte surface-associated sialylglycans and the expression of neuraminidase NEU1 and sialyltransferase ST6GAL1 genes in lymphocytes in erythremia patients and healthy donors as well as the levels of sialic acids in plasma and sialylation of alpha-acid glycoprotein and fibronectin. Moreover, we also investigated the type of sialic acids binding with its glycans using sialospecific lectins MAA and SNA. fibronectin protein in lymphocytes and its cell surface in erythremia disease as compared to healthy donors. It was shown that the levels of free sialic acids and neuraminidase activity in plasma are increased in erythremia disease as compared to healthy donors; however, MAA-II-binding activity of tested glycoproteins is decreased, fibronectin-1 mRNA expression in lymphocytes is increased in patients with erythremia. The decreasing of plasma fibronectin concentration and its heparin-binding activity as well as increasing of lymphocyte content with surface-associated and intracellular fibronectin were revealed in erythremia disease in comparison with healthy donors. Positive correlation between plasma fibronectin level and its heparin-binding activity and negative correlation between plasma fibronectin level and quantity of lymphocytes which express fibronectin inside the cell and on cell surface was detected. Enhanced levels of α2,3- and α2,6-linked residues of glycocojugates were detected on lymphocyte cell surface in erythremia disease using sialospecific lectins and flow cytometer as well as fluorescent confocal microscope. The level of NEU1 and ST6GAL1 mRNA expressions is significantly increased in lymphocytes in erythremia disease. Results of this study are clarified the mechanisms of disturbed in erythremia disease glycobiological processes and may therefore present new approaches for therapeutic opportunities.

Activity of trypsin-like enzymes and gelatinases in rats with doxorubicin cardiomyopathy.

Activity of trypsin-like enzymes (ATLE) and gelatinases A and B were studied in the blood plasma and extracts from cardiac muscle, cerebral cortex and cerebellum of rats with cardiomyopathy caused by anthracycline antibiotic doxorubicin against the background of preventive application of corvitin and α-ketoglutarate. ATLE significantly increased in blood plasma and extracts from cerebral cortex but decreased in extracts from cardiac muscle and cerebellum in doxorubicin cardiomyopathy (DCMP). In addition, a significant increase of activity of both gelatinases in plasma and tissue extracts was observed. Preventive administration of corvitin and α-ketoglutarate resulted in differently directed changes of activity of the above mentioned enzymes in heart and brain tissues. Obtained data confirm the hypothesis about activation of proteolysis under the influence of anthracycline antibiotics and testify to selective effect of corvitin and α-ketoglutarate on ATLE and gelatinases.

A latitudinal gradient in seed nutrients of the forest herb Anemone nemorosa.

The nutrient concentration in seeds determines many aspects of potential success of the sexual reproductive phase of plants, including the seed predation probability, efficiency of seed dispersal and seedling performance. Despite considerable research interest in latitudinal gradients of foliar nutrients, a similar gradient for seeds remains unexplored. We investigated a potential latitudinal gradient in seed nutrient concentrations within the widespread European understorey forest herb Anemone nemorosa L. We sampled seeds of A. nemorosa in 15 populations along a 1900-km long latitudinal gradient at three to seven seed collection dates post-anthesis and investigated the relative effects of growing degree-hours >5 °C, soil characteristics and latitude on seed nutrient concentrations. Seed nitrogen, nitrogen:phosphorus ratio and calcium concentration decreased towards northern latitudes, while carbon:nitrogen ratios increased. When taking differences in growing degree-hours and measured soil characteristics into account and only considering the most mature seeds, the latitudinal decline remained particularly significant for seed nitrogen concentration. We argue that the decline in seed nitrogen concentration can be attributed to northward decreasing seed provisioning due to lower soil nitrogen availability or greater investment in clonal reproduction. This pattern may have large implications for the reproductive performance of this forest herb as the degree of seed provisioning ultimately co-determines seedling survival and reproductive success.

GAG-binding variants of tick-borne encephalitis virus.

Previously different authors described various flavivirus mutants with high affinity to cell glycosaminoglycans and low neuroinvasiveness in mice that were obtained consequently passages in cell cultures or in ticks. In present study the analysis of TBEV isolates has shown existence of GAG-binding variants in natural virus population. Affinity to GAG has been evaluated by sorption on heparin-Sepharose. GAG-binding phenotype corresponds to such virus properties, like small plaque phenotype in PEK cells, absence of hemagglutination at pH 6.4, and low neuroinvasiveness in mice. Mutations increasing charge of E protein were necessary but not sufficient for acquisition of GAG-binding phenotype. Molecular modeling and molecular dynamics simulation have shown that the flexibility of E protein molecule could bear influence on the phenotypic manifestation of substitutions increasing charge of the virions.

[Characteristic of carbohydrate components of chickens and human's fibronectins].

The paper presents new information about the carbohydrate structures of 39-days chicken's fibronectin. It is found out that chicken fibronectin contains mainly biantennary N-glycans with a core fucose and fucosylated O-glycans. It is shown that N-glycans of chicken fibronectin are poorly sialated, since this protein exhibits affinity for the PNA and weak binding to sialospecific SNA. A comparative analysis of lectin-binding activity of chicken and human fibronectins has shown that both glycoproteins differ in glycan composition.

[Fibronectin-1 expression in lymphocytes of patients with erythremia].

Expression of fibronectin-1 mRNA in lymphocytes in erythremia patients and healthy donors as well as fibronectin-1 concentration in plasma and its heparin-binding activity have been studied. Moreover, we also investigated the expression of fibronectin protein in lymphocytes and cell surface in erythremia disease as compared to healthy donors. It was shown that fibronectin-1 mRNA expression in lymphocytes is increased in patients with erythremia as compared to healthy donors. The decrease of plasma fibronectin concentration and its heparin-binding activity as well as the increase of lymphocyte content with surface-associated and intracellular fibronectin were revealed in erythremia disease in comparison with healthy donors. Positive correlation between plasma fibronectin level and its heparin-binding activity and negative correlation between plasma fibronectin level and quantity of lymphocytes which express fibronectin inside the cell and on cell surface was detected. Results of this investigation demonstrate that fibronectin-1 mRNA expression in lymphocytes is disturbed in erythremia disease and is accompanied by a decrease of fibronectin plasma level.

Changes in the content of protein and lipid oxidative modification products in tumor tissue at different stages of lung cancer.

The content of LPO products (conjugated dienes, MDA) and products of oxidative modification of proteins (protein carbonyl derivatives) is reduced in tumor tissue in comparison with normal tissue and varies depending on the disease stage.

[Effect of selenium-containing supplements on the indices of specific immunity and nonspecific resistance in chicken].

The deficit of selenium is related to immunity worsening. Selenium improves an immune answer and raises disease resistance. The aim of our work was to study the influence of organic selenium in comparison with inorganic selenium on the factors of unspecific resistance and state of humoral immunity of chicken-broilers.

[Evidence for the absence of tick-borne encephalitis virus RNA in bioassays].

Reverse transcription-polymerase chain reaction was used to develop a procedure with internal monitoring that may provide evidence for the absence of tick-borne encephalitis virus RNA in bioassays. The proposed procedure is useful in evaluating the safety and effectiveness of a tick-borne encephalitis vaccine.

Responses of ground vegetation to prolonged simulated acid rain in sub-arctic pine-birch forest.

The effects of prolonged simulated acid rain on percentage cover of ground vegetation, and on growth and reproduction of two dominating dwarf shrubs (Emapetrum nigrum and Vaccinium vaitisidaea) were examined in a field experiment in the Finnish Subarctic, in an area with low ambient levels of sulphur and nitrogen deposition. Acid rain treatments included moderate (pH 3.8) and high (pH 2.9) concentrations of either H2 SO4 , or HNO3 , or a mixture of them, and were compared with irrigated (pH 6) and dry control plots. Long-term application of acid rain caused significant alteration in the cover and composition of ground vegetation. Effects of acid ram depended on the accompanying anion and on pH. Sub-plots under different canopy tree species differed in responses indicating that spatial heterogeneity is important in predicting the effect of acidifying pollution on this plant community. In the bottom layer, acid rain caused significant reduction in cover of the cyanobacterial lichens Nephroma arcticum and Peltigera spp. Decrease in cover of fruticose lichens, mainly composed of Cladina spp., more likely resulted from additional watering. In the field layer, acid rain containing moderate concentrations of NO- 3 caused an increase in cover of graminoid species. There were only slight alterations in growth and cover of the two dominant evergreen dwarf shrubs, Enigrum and V. vitis-idaea, indicating that these species are tolerant to acid rain of as low as pH 3. Even some positive responses of dwarf shrubs were observed, depending on canopy tree. Application of acid rain of pH 3 to plots under pine trees caused an increase in cover of I, vitis-idaea and, when the nitric acid only was applied, a short-term increase in the number of new shoots of E. nigrum. In contrast to vegetative growth, reproduction of the dwarf shrubs was more strongly affected by acid rain, but this also depended on local conditions and anion composition of acid rain. On 'pine' plots, rain of pH 3 reduced the number of berries and flower buds on terminal current shoot of E. nigrum, however, this was partially compensated by an increase in berry production at the ramet level. Simulated acid rain had mainly negative effects on berry production by V. vitis-idaea.

[Alpha-fetoprotein: biochemical properties, function, and clinico-diagnostic significance]. / Alfa-fetoprotein: biokhimicheskie svostva, funktsii i kliniko-diagnosticheskoe znachenie.

The review is dedicated to the 30th anniversary of the opening and studying of alpha-fetoprotein (AFP). New data about molecular properties, structure and functions as well as regulation of AFP synthesis are presented. Clinical significance and prospects of the further study of this oncofetal glycoprotein has been discussed.

[Lectin-binding proteins of plasma membranes of a human trophoblast]. / Lektin-sviazyvaiushchie belki plazmaticheskikh membran trofoblasta cheloveka.

Spectra of lectin-binding proteins of the human trophoblast were studied by the method affinity blotting using a set of loctins conjugated with peroxidase. The set included lectins Lens culinaris (LcL), Canavalia ensiformis (Con A), Ricinus communis (RCA 1), Arachis hypogaea (PNA), Triticum vulgaris (WGA), Laburnum anagyroides (LAL). Presence of N- and O-glycans in the composition of proteins of plasmatic membranes of a trophoblast was shown, partial characteristics of their oligosugar chains being presented. Sialic acids were established to be absent in the composition of alkaline phosphatase of mature placenta.

[Solid-phase immunoenzyme analysis of alpha-fetoprotein in human blood serum]. / Tverdofaznyi immunofermentnyi analiz al'fa-fetoproteina v syvorotke krovi cheloveka.

A test system for enzyme immunoassay of alpha-fetoprotein (AFP) was developed on the basis of the diagnostic agents manufactured by the N. F. Gamaleya Research Institute of Epidemiology and Microbiology. The effect of shielding antibody active centers in sensitization of planes with excessive concentrations of antibodies was detected. The test system was used to measure AFP levels in blood sera of pregnant women. The results may be used for screening pregnant women for the prenatal diagnosis of fetal neural tube.

[Determination of alpha-fetoprotein in the serum of pregnant women by rocket-linear immunoelectrophoresis]. / Opredelenie alpha-fetoproteina v syvorotke krovi beremennykh metodom raketno-lineinogo immunoélektroforeza.

Rocket-linear immunoelectrophoresis enabled to estimate the alpha-fetoprotein content in blood serum of pregnant women. Sensitivity of the procedure constituted as low as 13-22 ng of the protein per I ml of blood serum. Concentration of the protein in blood serum depended on the period of pregnancy; middle values of normal content of alpha-fetoprotein in blood serum were estimated within various periods of pregnancy in women of the district studied. The procedure might be used simultaneously with immunoenzymatic and radioimmune methods in prenatal diagnosis of impairments in development of the fetus neural tube.

[Tissue specificity of the human brain protein D2]. / Tkanevaia spetsifichnost' belka D2 mozga cheloveka.

Protein D2 was isolated and purified from adult human brain by extraction with Triton X-100 as well as by chromatography on phenyl-sepharose, concanavalin A-sepharose, lysine-sepharose and hydroxylapatite. Specific rabbit antisera against purified protein D2 were raised. Crossed and rocket immunoelectrophoresis revealed an immunoreactive protein D2 in the fetal heart, fetal kidney and adult heart (8-15% of total content in adult brain tissue). Rocket-on-line immunoelectrophoresis revealed additionally small amounts of D2-like antigens in adult kidney (12%), adult liver (1.5%), and in adult lung and spleen (less than 1%). The differences in tissue distribution as revealed by rocket-on-line immunoelectrophoresis suggest the existence of special D2-like protein clone in some tissues with or several immunochemically identical domains.