Automated glycan assembly of a S. pneumoniae serotype 3 CPS antigen

Vaccines against S. pneumoniae, one of the most prevalent bacterial infections causing severe disease, rely on isolated capsular polysaccharide (CPS) that are conjugated to proteins. Such isolates contain a heterogeneous oligosaccharide mixture of different chain lengths and frame shifts. Access to defined synthetic S. pneumoniae CPS structures is desirable. Known syntheses of S. pneumoniae serotype 3 CPS rely on a time-consuming and low-yielding late-stage oxidation step, or use disaccharide building blocks which limits variability. Herein, we report the first iterative automated glycan assembly (AGA) of a conjugation-ready S. pneumoniae serotype 3 CPS trisaccharide. This oligosaccharide was assembled using a novel glucuronic acid building block to circumvent the need for a late-stage oxidation. The introduction of a washing step with the activator prior to each glycosylation cycle greatly increased the yields by neutralizing any residual base from deprotection steps in the synthetic cycle. This process improvement is applicable to AGA of many other oligosaccharides

Electron transport through self-assembled monolayers of tripeptides

We report how the electron transport through a solid-state metal/Gly-Gly-His tripeptide (GGH) monolayer/metal junction and the metal/GGH work function are modified by the GGH complexation with Cu2+ ions. Conducting AFM is used to measure the current-voltage histograms. The work function is characterized by combining macroscopic Kelvin probe and Kelvin probe force microscopy at the nanoscale. We observe that the Cu2+ ions complexation with the GGH monolayer is highly dependent on the molecular surface density and results in opposite trends. In the case of a high density monolayer the conformational changes are hindered by the proximity of the neighboring peptides, hence forming an insulating layer in response to copper-complexation. Whereas the slightly lower density monolayers allow for the conformational change to a looped peptide wrapping the Cu-ion, which results in a more conductive monolayer. Copper-ion complexation to the high- and low-density monolayers systematically induces an increase of the work functions. Copper-ion complexation to the low-density monolayer induces an increase of electron transport efficiency, while the copper-ion complexation to the high-density monolayer results in a slight decrease of electron transport. Both of the observed trends are in agreement with first-principle calculations. Complexed copper to low density GGH-monolayer induces a new gap state slightly above the Au Fermi energy that is absent in the high density monolayer.Comment: Full paper with supporting informatio

Оценка производственной технологичности конструкции в жизненном цикле изделия

On the basis of technical and economic analysis of the properties of relations between design and technological solutions, a method for the integral assessment of production manufacturability by combining individual manufacturability coefficients at different stages of the product life cycle is suggested. Separate coefficients take into account the influence degree of various constituent stages on the labor intensity of production and maintenance, repair and disposal of the product structure. Design and technological solutions in design systems imply the use of properties such as reflexivity, symmetry and transitivity. As a result, it is proposed to understand the properties set of the product design that determine its adaptability to achieve optimal costs in production and disposal for specified quality indicators and work conditions. A list of manufacturability coefficients of manufacturing a product design has been determined, including coefficients of purchase, repeatability of details and connections, material hardness, borrowing, typing, precision, roughness, mass. An examination of the effectiveness assessment the use tools, equipment and other objects of the technological environment at the stages design and technological production preparation is formalized. The examination includes an analysis of the frequency and duration of the meeting of structural parts elements and the tools state at the stages of their manufacture, operation and disposal.На основе технико-экономического анализа свойств отношений конструкторско-технологических решений предложен метод интегральной оценки производственной технологичности путем объединения отдельных коэффициентов технологичности на различных этапах жизненного цикла изделия. Отдельные коэффициенты учитывают степень влияния различных составляющих этапов на трудоемкость производства и обслуживания, ремонта и утилизации конструкции изделия. Конструкторско-технологические решения в системах проектирования предполагают использование таких свойств, как рефлексивность, симметричность и транзитивность. В результате предложено под производственной технологичностью понимать совокупность свойств конструкции изделия, определяющих ее приспособленность к достижению оптимальных затрат при производстве и утилизации для заданных показателей качества и условий выполнения работ. Определен перечень коэффициентов технологичности изготовления конструкции изделия, включающий коэффициенты покупаемости, повторяемости деталей и соединений, твердости материала, заимствования, типизации, точности, шероховатости, массы. Формализована экспертиза оценки эффективности применения инструментов, средств оснащения и других объектов технологической среды на стадиях конструкторской и технологической подготовки производства. Экспертиза включает анализ частоты и продолжительности встречи конструктивных элементов деталей и состояния инструментов на этапах их изготовления, эксплуатации и утилизации

РИСК-ОРИЕНТИРОВАННЫЙ ПОДХОД К РАЗРАБОТКЕ МЕТОДИК КОНТРОЛЯ

The necessity for scientific and methodical study of methods for monitoring the characteristics of flameresistance of building structures has the highest priority in the field of fire safety. The aim of this work was to provide the required degree of reliability of the results of quality control of flame-resistant coatings of building structures and high efficiency of decisions due to the risk-based approach to the development of control methods.Substantiated risk-based approach to the development of methods of control, involving the consideration on the basis of process model, control flame-resistance of building object in all possible potential problems that can cause the risk of incorrect decision-making. A model of the risks arising from the control of the flameretardant coating thickness has been developed. Two major risk groups have been identified. The first group is related to the uncertainty of coating thickness measurement at a single control point. The second group of risks is related to the unrepresentativeness of selective control over the entire surface of the construction object as a whole Potential risk sources have been identified for each group. For the entire range of sources of particular risks the results of studies of the mechanisms of their manifestation, the estimated degree of influence on the accuracy of the control of compliance of flame-retardant coating thickness requirements. The analysis is carried out on the basis of both theoretical and experimental statistical studies on a number of construction projects.According to the results of the analysis of all particular risks of control unreliability, rational ways of their minimization in the form of technical or organizational and technical measures, which are refl in the developed project of the control method, are proposed. Project control method was built on the basis of a agreed scheme of control of the thickness of the fl coating of building structures sequentially the three parties. Formulated and solved the task of the metrological control of the thickness of the flame-retardant coating as indirect measurement methods non-destructive thickness measurements. Theoretical and applied aspects of the process of flame-retardant coating thickness control of building structures under conditions of high risk of making incorrect decisions on the results of control are considered.Необходимость научно-методической проработки методик контроля характеристик огнестойкости строительных конструкций (СК) имеет наивысший приоритет в области обеспечения пожарной безопасности. Целью данной работы являлось обеспечение требуемой степени достоверности результатов контроля качества огнестойких покрытий строительных конструкций и высокой эффективности принимаемых решений за счет риск-ориентированного подхода к разработке методики контроля.Обоснован риск-ориентированный подход к разработке методики контроля, предполагающий рассмотрение на базе процессной модели контроля огнестойкости строительного объекта всех возможных потенциальных проблем, которые могут вызвать риск некорректного принятия решения. Разработана модель рисков, возникающих при контроле толщины огнезащитного покрытия. Идентифицированы две основные группы рисков. Первая группа связана с неопределенностью измерения толщины покрытия в единичной точке контроля. Вторая группа рисков связана с нерепрезентативностью выборочного контроля всей поверхности строительного объекта в целом. Для каждой группы определены потенциальные источники рисков. Для всего комплекса источников частных рисков приведены результаты исследований механизмов их проявления, оценена степень влияния на достоверность контроля соответствия толщины огнезащитного покрытия требованиям. Анализ проведен на основе как теоретических, так и экспериментальных статистических исследований на ряде строительных объектов.По результатам анализа всех частных рисков недостоверности контроля предложены рациональные пути их минимизации в виде технических или организационно-технических мер, нашедших отражение в разработанном проекте методики контроля. Проект методики контроля построен на основе согласованной схемы контроля толщины огнезащитного покрытия строительных конструкций последовательно тремя сторонами.Сформулирована и решена метрологическая задача контроля толщины огнезащитного покрытия как косвенное измерение неразрушающими методами толщинометрии. Рассмотрены теоретические и прикладные аспекты процесса контроля толщины огнезащитного покрытия строительных конструкций в условиях высокого риска принятия некорректного решения по результатам контроля

IL-1 enhances expansion, effector function, tissue localization, and memory response of antigen-specific CD8 T cells

Here, we show that interleukin-1 (IL-1) enhances antigen-driven CD8 T cell responses. When administered to recipients of OT-I T cell receptor transgenic CD8 T cells specific for an ovalbumin (OVA) peptide, IL-1 results in an increase in the numbers of wild-type but not IL1R1−/− OT-I cells, particularly in spleen, liver, and lung, upon immunization with OVA and lipopolysaccharide. IL-1 administration also results in an enhancement in the frequency of antigen-specific cells that are granzyme B+, have cytotoxic activity, and/ or produce interferon γ (IFN-γ). Cells primed in the presence of IL-1 display enhanced expression of granzyme B and increased capacity to produce IFN-γ when rechallenged 2 mo after priming. In three in vivo models, IL-1 enhances the protective value of weak immunogens. Thus, IL-1 has a marked enhancing effect on antigen-specific CD8 T cell expansion, differentiation, migration to the periphery, and memory

Optima TB: A tool to help optimally allocate tuberculosis spending.

Approximately 85% of tuberculosis (TB) related deaths occur in low- and middle-income countries where health resources are scarce. Effective priority setting is required to maximise the impact of limited budgets. The Optima TB tool has been developed to support analytical capacity and inform evidence-based priority setting processes for TB health benefits package design. This paper outlines the Optima TB framework and how it was applied in Belarus, an upper-middle income country in Eastern Europe with a relatively high burden of TB. Optima TB is a population-based disease transmission model, with programmatic cost functions and an optimisation algorithm. Modelled populations include age-differentiated general populations and higher-risk populations such as people living with HIV. Populations and prospective interventions are defined in consultation with local stakeholders. In partnership with the latter, demographic, epidemiological, programmatic, as well as cost and spending data for these populations and interventions are then collated. An optimisation analysis of TB spending was conducted in Belarus, using program objectives and constraints defined in collaboration with local stakeholders, which included experts, decision makers, funders and organisations involved in service delivery, support and technical assistance. These analyses show that it is possible to improve health impact by redistributing current TB spending in Belarus. Specifically, shifting funding from inpatient- to outpatient-focused care models, and from mass screening to active case finding strategies, could reduce TB prevalence and mortality by up to 45% and 50%, respectively, by 2035. In addition, an optimised allocation of TB spending could lead to a reduction in drug-resistant TB infections by 40% over this period. This would support progress towards national TB targets without additional financial resources. The case study in Belarus demonstrates how reallocations of spending across existing and new interventions could have a substantial impact on TB outcomes. This highlights the potential for Optima TB and similar modelling tools to support evidence-based priority setting

Prospective evaluation of improving fluoroquinolone exposure using centralised therapeutic drug monitoring (TDM) in patients with tuberculosis (PERFECT): a study protocol of a prospective multicentre cohort study

Introduction Global multidrug-resistant tuberculosis (MDR-TB) treatment success rates remain suboptimal. Highly active WHO group A drugs moxifloxacin and levofloxacin show intraindividual and interindividual pharmacokinetic variability which can cause low drug exposure. Therefore, therapeutic drug monitoring (TDM) of fluoroquinolones is recommended to personalise the drug dosage, aiming to prevent the development of drug resistance and optimise treatment. However, TDM is considered laborious and expensive, and the clinical benefit in MDR-TB has not been extensively studied. This observational multicentre study aims to determine the feasibility of centralised TDM and to investigate the impact of fluoroquinolone TDM on sputum conversion rates in patients with MDR-TB compared with historical controls. Methods and analysis Patients aged 18 years or older with sputum smear and culture-positive pulmonary MDR-TB will be eligible for inclusion. Patients receiving TDM using a limited sampling strategy (t=0 and t=5 hours) will be matched to historical controls without TDM in a 1:2 ratio. Sample analysis and dosing advice will be performed in a centralised laboratory. Centralised TDM will be considered feasible if >80% of the dosing recommendations are returned within 7 days after sampling and 100% within 14 days. The number of patients who are sputum smear and culture-negative after 2 months of treatment will be determined in the prospective TDM group and will be compared with the control group without TDM to determine the impact of TDM. Ethics and dissemination Ethical clearance was obtained by the ethical review committees of the 10 participating hospitals according to local procedures or is pending (online supplementary file 1). Patients will be included after obtaining written informed consent. We aim to publish the study results in a peer-reviewed journal. Trial registration number ClinicalTrials.gov Registry (NCT03409315)

Deciphering the Arginine-Binding Preferences at the Substrate-Binding Groove of Ser/Thr Kinases by Computational Surface Mapping

Protein kinases are key signaling enzymes that catalyze the transfer of γ-phosphate from an ATP molecule to a phospho-accepting residue in the substrate. Unraveling the molecular features that govern the preference of kinases for particular residues flanking the phosphoacceptor is important for understanding kinase specificities toward their substrates and for designing substrate-like peptidic inhibitors. We applied ANCHORSmap, a new fragment-based computational approach for mapping amino acid side chains on protein surfaces, to predict and characterize the preference of kinases toward Arginine binding. We focus on positions P−2 and P−5, commonly occupied by Arginine (Arg) in substrates of basophilic Ser/Thr kinases. The method accurately identified all the P−2/P−5 Arg binding sites previously determined by X-ray crystallography and produced Arg preferences that corresponded to those experimentally found by peptide arrays. The predicted Arg-binding positions and their associated pockets were analyzed in terms of shape, physicochemical properties, amino acid composition, and in-silico mutagenesis, providing structural rationalization for previously unexplained trends in kinase preferences toward Arg moieties. This methodology sheds light on several kinases that were described in the literature as having non-trivial preferences for Arg, and provides some surprising departures from the prevailing views regarding residues that determine kinase specificity toward Arg. In particular, we found that the preference for a P−5 Arg is not necessarily governed by the 170/230 acidic pair, as was previously assumed, but by several different pairs of acidic residues, selected from positions 133, 169, and 230 (PKA numbering). The acidic residue at position 230 serves as a pivotal element in recognizing Arg from both the P−2 and P−5 positions

Optima TB: A tool to help optimally allocate tuberculosis spending

Approximately 85% of tuberculosis (TB) related deaths occur in low- and middle-income countries where health resources are scarce. Effective priority setting is required to maximise the impact of limited budgets. The Optima TB tool has been developed to support analytical capacity and inform evidence-based priority setting processes for TB health benefits package design. This paper outlines the Optima TB framework and how it was applied in Belarus, an upper-middle income country in Eastern Europe with a relatively high burden of TB. Optima TB is a population-based disease transmission model, with programmatic cost functions and an optimisation algorithm. Modelled populations include age-differentiated general populations and higher-risk populations such as people living with HIV. Populations and prospective interventions are defined in consultation with local stakeholders. In partnership with the latter, demographic, epidemiological, programmatic, as well as cost and spending data for these populations and interventions are then collated. An optimisation analysis of TB spending was conducted in Belarus, using program objectives and constraints defined in collaboration with local stakeholders, which included experts, decision makers, funders and organisations involved in service delivery, support and technical assistance. These analyses show that it is possible to improve health impact by redistributing current TB spending in Belarus. Specifically, shifting funding from inpatient- to outpatient-focused care models, and from mass screening to active case finding strategies, could reduce TB prevalence and mortality by up to 45% and 50%, respectively, by 2035. In addition, an optimised allocation of TB spending could lead to a reduction in drug-resistant TB infections by 40% over this period. This would support progress towards national TB targets without additional financial resources. The case study in Belarus demonstrates how reallocations of spending across existing and new interventions could have a substantial impact on TB outcomes. This highlights the potential for Optima TB and similar modelling tools to support evidence-based priority setting