384 research outputs found

    Chemical composition of Rhododendron aureum (gold rosebay) essential oil from Pribaikal’e (Russian Federation)

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    The essential oils from five samples of leaves of Rhododendron aureum from the Irkutsk region, Pribaikal’e, Russian Federation, were isolated by hydrodistillation and analyzed by a combination of GC and GC/MS. Compounds representing 70.5–78.3 % of the oils were identified. Twenty-seven compounds were identified according to their chromatographic retention indices and mass spectra. The major components of the oils were calarene (10.4––66.4 %), b-bourbonene (0.5–27.4 %), a-selinene (2.1–8.0 %) and kaur-16-ene (2.0–6.3 %). It was found that the chemical composition of Rh. aureum essential oil depends on the altitude of the growing plants

    The role of endothelial dysfunction and subclinical inflammation in the development of obstetric and perinatal complications in diabetes mellitus patients

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    Diabetes mellitus in pregnant women is one of the topical problems of modern medicine. Recently, there has been an increase in cases of type 2 diabetes, especially an increase in the frequency of early onset in children and adolescents, respectively, in the fertile age, in a few years; they will enter with the burden of pathology. This is particularly problematic and important during pregnancy, since type 1 and type 2 diabetes are accompanied by a high risk of adverse obstetric and perinatal complications, which are detected in most women with type 1 and type 2 diabetes. The purpose of this review was to assess the role of vascular endothelial dysfunction and subclinical inflammation in the genesis of placental insufficiency causing the development of a number of pregnancy complications in diabetes mellitus, to search for biological markers of these processes, which may reveal some pathogenetic mechanisms for the formation and diagnosis of these disorders.The review shows changes in the content of a number of biological markers, primarily such as pro-inflammatory cytokines (IL-1, TNFα, IL-6); CRP, for certain pregnancy complications in diabetes mellitus women. It is the imbalance of cytokines that very often determines the development of gestational complications and disrupts immunological tolerance in the mother-placenta-fetus system. The degree of severity of angiogenesis processes depends on the level of hyperglycemia, manifestations of subclinical inflammation and is reflected in the increase in the VEGF expression level and its receptors in terminal and stem villi of the placenta.Thus, the review shows the role of endothelial dysfunction and subclinical inflammation in the development of obstetric and perinatal complications in diabetes mellitus patients, which is indicated by the changes in a range of proinflammatory cytokines and other biologically active markers

    Functional characterization of a melon alcohol acyl-transferase gene family involved in the biosynthesis of ester volatiles. Identification of the crucial role of a threonine residue for enzyme activity

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    Volatile esters, a major class of compounds contributing to the aroma of many fruit, are synthesized by alcohol acyl-transferases (AAT). We demonstrate here that, in Charentais melon (Cucumis melo var. cantalupensis), AAT are encoded by a gene family of at least four members with amino acid identity ranging from 84% (Cm-AAT1/Cm-AAT2) and 58% (Cm-AAT1/Cm-AAT3) to only 22% (Cm-AAT1/Cm-AAT4). All encoded proteins, except Cm-AAT2, were enzymatically active upon expression in yeast and show differential substrate preferences. Cm-AAT1 protein produces a wide range of short and long-chain acyl esters but has strong preference for the formation of E-2-hexenyl acetate and hexyl hexanoate. Cm-AAT3 also accepts a wide range of substrates but with very strong preference for producing benzyl acetate. Cm-AAT4 is almost exclusively devoted to the formation of acetates, with strong preference for cinnamoyl acetate. Site directed mutagenesis demonstrated that the failure of Cm-AAT2 to produce volatile esters is related to the presence of a 268-alanine residue instead of threonine as in all active AAT proteins. Mutating 268-A into 268-T of Cm-AAT2 restored enzyme activity, while mutating 268-T into 268-A abolished activity of Cm-AAT1. Activities of all three proteins measured with the prefered substrates sharply increase during fruit ripening. The expression of all Cm-AAT genes is up-regulated during ripening and inhibited in antisense ACC oxidase melons and in fruit treated with the ethylene antagonist 1-methylcyclopropene (1-MCP), indicating a positive regulation by ethylene. The data presented in this work suggest that the multiplicity of AAT genes accounts for the great diversity of esters formed in melon

    ODORANT1 targets multiple metabolic networks in petunia flowers

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    Scent bouquets produced by the flowers of Petunia spp. (petunia) are composed of a complex mixture of floral volatile benzenoid and phenylpropanoid compounds (FVBPs), which are specialized metabolites derived from phenylalanine (Phe) through an interconnected network of enzymes. The biosynthesis and emission of high levels of these volatiles requires coordinated transcriptional activation of both primary and specialized metabolic networks. The petunia R2R3‐MYB transcription factor ODORANT 1 (ODO1) was identified as a master regulator of FVBP production and emission; however, our knowledge of the direct regulatory targets of ODO1 has remained limited. Using chromatin immunoprecipitation followed by sequencing (ChIP‐seq) in petunia flowers, we identify genome‐wide ODO1‐bound genes that are enriched not only in genes involved in the biosynthesis of the Phe precursor, as previously reported, but also genes associated with the specialized metabolic pathways involved in generating phenylpropanoid intermediates for FVBPs. ODO1‐bound genes are also involved in methionine and S‐adenosylmethionine metabolism, which could modulate methyl group supplies for certain FVBPs. Quantitative reverse transcription polymerase chain reaction (qRT‐PCR) and RNA‐seq analysis in an ODO1 RNAi knockdown line revealed that ODO1‐bound targets are expressed at lower levels when ODO1 is suppressed. A cis‐regulatory motif, CACCAACCCC, was identified as a potential binding site for ODO1 in the promoters of genes that are both bound and activated by ODO1, which was validated by in planta promoter reporter assays with wild‐type and mutated promoters. Overall, our work presents a mechanistic model for ODO1 controlling an extensive gene regulatory network that contributes to FVBP production to give rise to floral scent

    Modern Trends Functioning of the Insurance Services Market of Russia

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    At the present stage, there is a further development of the insurance market, which is associated with the integration processes taking place on it, affecting the participants of insurance activities. The changes observed in various segments of the economy lead to increase in various risks and increase the need for insurance services. In Russia, one of the problems is a small set of proposed insurance services, which affects the development of the insurance market. The purpose of the article is to assess the current state of the insurance services market in Russia and identify problems arising in its functioning. The research methodology consists in the synthesis and comparison of data characterizing various components of the insurance services market. The authors identify the trends that have developed on the market of insurance in Russia, assesses the current situation according to different criteria, revealed the factors of development of insurance business, as well as the problem aspects of the insurance industry. The study showed the presence of high dependence of insurance in Russia on the prevailing political and economic way of life here, which led to the domination of demand for certain insurance products. As a result, it can be noted that the development of the modern market of insurance is associated with the need for state support, which consists in creating conditions for the adequate functioning of the insurance market. The authors substantiate the need to develop an insurance ideology and bring its essence to the population

    The biosynthesis of thymol, carvacrol, and thymohydroquinone in Lamiaceae proceeds via cytochrome P450s and a short-chain dehydrogenase

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    Thymol and carvacrol are phenolic monoterpenes found in thyme, oregano, and several other species of the Lamiaceae. Long valued for their smell and taste, these substances also have antibacterial and anti-spasmolytic properties. They are also suggested to be precursors of thymohydroquinone and thymoquinone, monoterpenes with anti-inflammatory, antioxidant, and antitumor activities. Thymol and carvacrol biosynthesis has been proposed to proceed by the cyclization of geranyl diphosphate to γ-terpinene, followed by a series of oxidations via p-cymene. Here, we show that γ-terpinene is oxidized by cytochrome P450 monooxygenases (P450s) of the CYP71D subfamily to produce unstable cyclohexadienol intermediates, which are then dehydrogenated by a short-chain dehydrogenase/reductase (SDR) to the corresponding ketones. The subsequent formation of the aromatic compounds occurs via keto–enol tautomerisms. Combining these enzymes with γ-terpinene in in vitro assays or in vivo in Nicotiana benthamiana yielded thymol and carvacrol as products. In the absence of the SDRs, only p-cymene was formed by rearrangement of the cyclohexadienol intermediates. The nature of these unstable intermediates was inferred from reactions with the γ-terpinene isomer limonene and by analogy to reactions catalyzed by related enzymes. We also identified and characterized two P450s of the CYP76S and CYP736A subfamilies that catalyze the hydroxylation of thymol and carvacrol to thymohydroquinone when heterologously expressed in yeast and N. benthamiana. Our findings alter previous views of thymol and carvacrol formation, identify the enzymes involved in the biosynthesis of these phenolic monoterpenes and thymohydroquinone in the Lamiaceae, and provide targets for metabolic engineering of high-value terpenes in plants

    Model formation of functional and mathematical literacy in the process of teaching mathematics

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    Цель данного исследования - создание структурно-логической модели как основы для разработки методики обучения математике, способствующей формированию математической грамотности обучающихся на всех ступенях образования (дошкольный, младший школьный возраст, профессиональное и высшее образование).The purpose of this study is to create a structural and logical model as a basis for developing a methodology for teaching mathematics that contributes to the formation of mathematical literacy of students at all levels of education (preschool, primary school age, vocational and higher education)

    Student Mathematical Olympiads and Competitions in USPU as an Informal Level Indicator and a Tool of Motivation for Deepening the Subject Training of Future Teachers

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    В статье обобщен опыт практической работы авторов, представляющих коллектив кафедры высшей математики и методики обучения математике Института математики, физики, информатики и технологий ФГБОУ ВО "Уральский государственный педагогический университет", по организации и проведению математических олимпиад и других математических конкурсов от городского вплоть до международного уровней.The article summarizes the experience of practical work of authors representing the team of the Department of Higher Mathematics and Methods of Teaching Mathematics of the Institute of Mathematics, Physics, Informatics and Technology of the Ural State Pedagogical University, on the organization and conduct of mathematical Olympiads and other mathematical competitions from urban to international level
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