251 research outputs found

    Examining c-di-GMP and possible quorum sensing regulation in Pseudomonas fluorescens SBW25:links between intra and inter-cellular regulation benefits community cooperative activities such as biofilm formation

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    Bacterial success in colonizing complex environments requires individual response to micro-scale conditions as well as community-level cooperation to produce large-scale structures such as biofilms. Connecting individual and community responses could be achieved by linking the intracellular sensory and regulatory systems mediated by bis-(3′-5′)-cyclic dimeric guanosine monophosphate (c-di-GMP) and other compounds of individuals with intercellular quorum sensing (QS) regulation controlling populations. There is growing evidence to suggest that biofilm formation by many pseudomonads is regulated by both intra and intercellular systems, though in the case of the model Pseudomonas fluorescens SBW25 Wrinkly Spreader in which mutations increasing c-di-GMP levels result in the production of a robust cellulose-based air-liquid interface biofilm, no evidence for the involvement of QS regulation has been reported. However, our recent review of the P. fluorescens SBW25 genome has identified a potential QS regulatory pathway and other QS–associated genes linked to c-di-GMP homeostasis, and QS signal molecules have also been identified in culture supernatants. These findings suggest a possible link between c-di-GMP and QS regulation in P. fluorescens SBW25 which might allow a more sophisticated and responsive control of cellulose production and biofilm formation when colonising the soil and plant-associated environments P. fluorescens SBW25 normally inhabits.Анализ ц-ди-ГМФ и возможного чувства кворума у Pseudomonas fluorescens SBW 25: связь между внутри и межклеточной регуляцией способствует кооперативному поведению в сообществе и формированию биоплёнкиУспешность бактериальной колонизации сложных экониш требует индивидуального ответа на изменения условий на микроуровне равно как и кооперации на уровне сообщества для продукции таких крупно масштабных структур как биоплёнки. Координация индивидуальных ответ ов и ответов сообщества может быть достигнута путем связывания внутриклеточных сенсорных и регуляторных систем, опосредуемых бис-(3',5')-циклическим димерным гуанозинмонофосфатом (ц-ди-ГМФ) и другими соединениями индивидуумов с межклеточной регуляцией - чувством кворума (ЧК), контролирующем популяци ю. Накапливается всё больше доказательств того, что формирование биопленки многими псевдомонадами регулируется как внутри клеточными, так и меж клеточными регуляторными системами, хотя в случае модельной Pseudomonas fluorescens SBW25 Wrinkly Spreader, у которой мутации, повышающ ие уровни ц-ди-ГМФ, приводят к созданию прочной целлюлозной биоплёнки на границе раздела фаз воздух-жидкость, не было обнаружено ни ка кого свидетельства вовлечения кворум-зависимой регуляции. Однако наш недавний обзор генома P. fluorescens SBW25 выявил потенциальный ЧК-зависимый регуляторный пу ть и другие ЧК-зависимые гены, связанные с гомеостазом ц-ди-ГМФ, а молекулы ЧК-сигналинга были идентифицированы в культуре. Эти данные свидетельствуют о возможной связи между ц-ди-ГМФ-регуляцией и ЧК у P. fluorescens SBW25, что позволяет более сложный и гибкий контроль над продукцией целлюлозы и образовани ем биопленки при колонизации почв и экониш, aссоциированных с растениям и, - естественными средами обитания P. fluorescens SBW25

    Analysis of the applicability of methods for predicting and assessing accidents at conflict sites in the transportation network and prospects for their development

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    Accident rate is one of the most significant losses in road traffic, as it affects each of the road users. Therefore, in order to reduce its level, it is necessary to develop a modern method of accident prediction, which would allow to accurately estimate the number of accidents and the severity of consequences not only by experimental data and survey results, but also by modelling at the decision-making stage. Such a method is the method of conflict situations, but to date it is characterized by low accuracy of prediction, not applicable for practical use, as well as the severity of obtaining (collection and analysis) of raw data and lack of automation of the decision-making process to select the optimal measure by the method of conflict situations. In the article the analysis of existing methods of accident forecasting, as sessment of their applicability at different stages of decision-making, as well as further prospects and directions of improvement of the method of conflict situations for the purpose of its applicability in the practice of traffic management for the purpose of optimizing its options and modes of regulation are determined

    ГЕНЕРАТОРЫ КАЧАЮЩЕЙСЯ ЧАСТОТЫ МИЛЛИМЕТРОВОГО ДИАПАЗОНА ДЛИН ВОЛН С УМНОЖЕНИЕМ ЧАСТОТЫ

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    The structure of the construction of solid-state oscillating frequency oscillators in individual subranges of the millimeter wavelength range is given. In addition, the proposed principles for implementing the generation of signals in a wide range of frequency bands.Приведена структура построения твердотельных генераторов качающейся частоты в отдельных поддиапазонах миллиметрового диапазона длин волн. Кроме того, предложены принципы реализации генерации сигналов в широком спектре диапазонов частот

    О ФИЗИОЛОГИЧЕСКОМ СТАТУСЕ НЕКОТОРЫХ СТЕРОИДНЫХ ГЛИКОЗИДОВ РАСТЕНИЙ

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    The comparative study of the processes of growth, organ formation and physiological and biochemical responses of plants in experiences in vitro and in vivo are carried out under influence steroid glycosides and plant hormones (auxins, gibberellins and cytokinins). The common and specific properties of these connections are revealed. On the strength of these properties, the steroid glycosides are referred to new group steroid phytohormones. The general properties of steroid glycosides are optimization of all the known processes of growth and morphogenesis (intensification of the growth of stems, leaves and roots of wheat, apical dominance in barley and wheat, accelerating germination of freshly harvested potato tubers, the increase of pigment content in the cereals leaves, the cotyledons of pumpkin and amaranth seedlings, the accumulation of biomass in clover plants), attraversa ability and regulation of physiological and biochemical processes of plants. The new plant hormones are hydrophilic conjugate that activates juvenile and volumetric growth, with prolonged activity, high stability and transportability in plants.Изучение процессов роста разных органов и видов растений в опытах in vivo и in vitro, особенностей органо- образования, физиолого-биохимических реакций и функций стероидных гликозидов на фоне известных фитогормонов ауксинов, гиббереллинов и цитокининов позволило выявить как общие, так и специфические свойства этой группы природных регуляторов роста, по совокупности которых они отнесены к новой группе стероидных фитогормонов, имеющих наиболее широкое сходство с ауксином. К общим свойствам стероидных гликозидов можно отнести рост растяжением колеоптилей злаков, интенсификацию роста стеблей, листьев и корней пшеницы, апикальное доминирование у ячменя и пшеницы, ускорение прорастания свежеубранных клубней картофеля, повышение содержания пигментов в листьях злаков, семядолях тыквы и проростках щирицы, накопление биомассы в растениях клевера, т. е. оптимизирование всех известных процессов роста и формообразования, а также аттрагирующую способность и регуляцию физиолого-биохимических процессов растений. Отличительные особенности новых фитогормонов – гидрофильные конъюгаты, активирующие ювенильный и объемный рост, обладающие пролонгированной активностью, высокой стабильностью и транспортабельностью в растениях.

    Лабораторные маркёры полиорганной патологии при тяжёлом течении и неблагоприятных исходах инфекции SARS-CoV-2 (систематический обзор литературы)

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    The aim of the review: to present up-to-date scientifically based information about the laboratory parameters of patients associated with severe SARS-CoV-2 infection and internal organ damage. Materials and methods: full-text publications of clinical, randomized and cohort studies, systematic reviews and meta-analyses from scientific databases PubMed, Elsevier, Scopus, Google Scholar, E-library for the period from 2019 to 2022 were analyzed. Results. Specific biomarkers were identified, including inflammatory and immunological parameters (C-reactive protein, procalcitonin, IL6), hematological (number of lymphocytes and neutrophils, NLR, D-dimer, ferritin, RDW), myocardial (troponin, creatinekinase-MB, myoglobin), hepatic (AST, ALT, total bilirubin, albumin) and characterizing lung injury (KL-6), which can be used for risk stratification, as prognostic biomarkers of adverse clinical consequences, including death in patients with COVID-19. The studies demonstrated new biomarkers of inflammatory and systemic manifestations of COVID19: procalcitonin, calprotectin and presepsin.Представлены современные научно обоснованные сведения о лабораторных параметрах пациентов с тяжёлым течением и неблагоприятными исходами инфекции SARS-CoV-2. Проанализированы полнотекстовые публикации клинических, рандомизированных и когортных исследований, систематические обзоры и мета-анализы из научных баз PubMed, Elsevier, Scopus, Google Scholar, E-library за период с 2019 по 2022 г. Определены конкретные биомаркеры, включая воспалительные и иммунологические параметры (C-реактивный белок, прокальцитонин, интерлейкин-6, D-димер, ферритин), гематологические (количество нейтрофилов, лимфоцитов, их соотношение, RDW), миокардиальные (тропонин, креатинкиназа, миоглобин), печеночные (АСТ, АЛТ, общий билирубин, альбумин) и характеризующие повреждение легких (гликопротеин Кребса фон ден Лунгена-6), которые могут быть использованы для стратификации риска, в качестве прогностических критериев неблагоприятного течения заболевания, в том числе полиорганной недостаточности, тяжёлого  течения и летального исхода пациентов с COVID-19. В исследованиях продемонстрирована роль новых биомаркеров воспалительных и системных проявлений COVID-19: прокальцитонина, кальпротектина и пресепсина

    The background in the neutrinoless double beta decay experiment GERDA

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    The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double beta decay of 76Ge. The signature of the signal is a monoenergetic peak at 2039 keV, the Q-value of the decay, Q_bb. To avoid bias in the signal search, the present analysis does not consider all those events, that fall in a 40 keV wide region centered around Q_bb. The main parameters needed for the neutrinoless double beta decay analysis are described. A background model was developed to describe the observed energy spectrum. The model contains several contributions, that are expected on the basis of material screening or that are established by the observation of characteristic structures in the energy spectrum. The model predicts a flat energy spectrum for the blinding window around Q_bb with a background index ranging from 17.6 to 23.8*10^{-3} counts/(keV kg yr). A part of the data not considered before has been used to test if the predictions of the background model are consistent. The observed number of events in this energy region is consistent with the background model. The background at Q-bb is dominated by close sources, mainly due to 42K, 214Bi, 228Th, 60Co and alpha emitting isotopes from the 226Ra decay chain. The individual fractions depend on the assumed locations of the contaminants. It is shown, that after removal of the known gamma peaks, the energy spectrum can be fitted in an energy range of 200 kev around Q_bb with a constant background. This gives a background index consistent with the full model and uncertainties of the same size

    Advanced liver disease in Russian children and adolescents with chronic hepatitis C

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    Russia has one of the highest prevalences of paediatric chronic hepatitis C infection (CHC). Our aim was to provide a detailed characterization of children and adolescents with CHC including treatment outcomes.Thus, an observational study of children with CHC aged <18 years was conducted in three hepatology centres from November 2014 to May 2017. Of 301 children(52% male), 196(65%) acquired HCV vertically, 70(23%) had a history of blood transfusion or invasive procedures, 1 injecting drug use and 34(11%) had no known risk factors. Median age at HCV diagnosis was 3.1[IQR 1.1,8.2] and 10.8[7.4,14.7] at last follow-up. The most common genotype was 1b(51%), followed by 3(31%). Over a quarter of patients (84,28%) had raised liver transaminases. Of 92 with liver biopsy, 38(41%) had bridging fibrosis (median age 10.4[7.1,14.1]). Of 223 evaluated by transient elastography (TE), 67(30%) had liver stiffness ≥5.0kPa. For each year increase in age mean stiffness increased by 0.09kPa(95%CI 0.05,0.13, p<0.001). There was significant correlation between liver stiffness and biopsy results (Tau-b=0.29, p=0.042). Of 205 treated with IFN-based regimens, 100(49%) had SVR24. Most children (191,93%) experienced adverse reactions, leading to treatment discontinuation in 6(3%). In conclusion, a third of children acquired HCV via non-vertical routes and a substantial proportion of those with liver biopsy had advanced liver disease. Only half of children achieved SVR24 with IFN-based regimens highlighting the need for more effective and better tolerated treatments with direct-acting antivirals. Further studies are warranted in Russia on causes and prevention of non-vertical transmission of HCV in children. This article is protected by copyright. All rights reserved

    Status of the GERDA experiment

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    The study of neutrinoless double beta (0nbb) decay is the only one presently known approach to the fundamental question if the neutrino is a Majorana particle, i.e. its own anti-particle. The observation of 0nbb decay would prove that lepton number is not conserved, establish that neutrino has a Majorana component and, assuming that light neutrino is the dominating process, provide a method for the determination of its effective mass. GERDA is a new 0nbb decay experiment which is currently taking data at the Laboratori Nazionali del Gran Sasso (LNGS) of INFN in Italy. It implements a new shielding concept by operating bare diodes made from Ge with enriched 76Ge in high purity liquid argon supplemented by a water shield. The aim of GERDA is to verify or refute the recent claim of discovery, and, in a second phase, to achieve a two orders of magnitude lower background index than past experiments, to increase the sensitive mass and to collect an exposure of 100 kg yr. The paper will discuss design, physics reach, and status of data taking of GERDA.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard
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