EELS study of the epitaxial graphene/Ni(111) and graphene/Au/Ni(111) systems

We have performed electron energy-loss spectroscopy (EELS) studies of Ni(111), graphene/Ni(111), and the graphene/Au/Ni(111) intercalation-like system at different primary electron energies. A reduced parabolic dispersion of the \pi plasmon excitation for the graphene/Ni(111) system is observed compared to that for bulk pristine and intercalated graphite and to linear for free graphene, reflecting the strong changes in the electronic structure of graphene on Ni(111) relative to free-standing graphene. We have also found that intercalation of gold underneath a graphene layer on Ni(111) leads to the disappearance of the EELS spectral features which are characteristic of the graphene/Ni(111) interface. At the same time the shift of the \pi plasmon to the lower loss-energies is observed, indicating the transition of initial system of strongly bonded graphene on Ni(111) to a quasi free-standing-like graphene state.Comment: 31 pages, 5 figures, accepted in Carbo

Instructions for laboratory training in General Microbiology & Immunology

МИКРОБИОЛОГИЯАЛЛЕРГОЛОГИЯ И ИММУНОЛОГИЯМЕТОДИЧЕСКИЕ УКАЗАНИЯЛАБОРАТОРНЫЕ РАБОТЫПРАКТИЧЕСКИЕ НАВЫКИСодержатся план, программа практических занятий и основные практические навыки по общей микробиологии и иммунологии

Cell Structures in Heterologous Anti-Rabies Immunoglobulin Production

This paper reviews basic modern trends in obtainment of anti-rabies immunoglobulin with enhanced properties. One of these trends is associated with the substitution of organ-tissue antigen by cultural antigen at the stage of producer immunization. Analyzed are the results of research connected with the use of the cell-cultures grown Rabies virus in production of heterologous anti-rabies immunoglobulin. The study testifies of applicability of the transferred Vero cell culture as a substrate for rabies antigen preparation. In addition to this, specified are the advantages of the rabies cultural antigen usage over the organ-tissue one at the stage of hyper-immune serum production

GAS CHROMATOGRAPHY TECHNIQUE OPTIMIZATION FOR CHECKING RESIDUAL ETHANOL IN THE PREPARATION OF HETEROLOGOUS ANTI-RABIES IMMUNOGLOBULIN

The article presents the results of determination of residual ethanol in the preparation of heterologous antirabies immunoglobulin, using portable photoionization gas chromatograph PGC-1. The advantages of the method are as follows: accuracy, sensitivity, promptness. It does not require sample preparation; the results can be processed automatically

Experimental Substantiation of Cultural Technologies Introduction into Manufacturing of Anti-Rabies Immunoglobulin

The review provides information on the major outcomes of research and development work, performed within the frames of the Federal Target Program “National system of chemical and biological safety” (2009-2014), aimed at elaboration and introduction of cultural techniques into the manufacturing of anti-rabies immunoglobulin. Described are the key phases in methodology engineering, deployed for the large-scale cultivation of fixed rabies virus, concentration of cultural liquid, quantitation of rabies virus using PCR, and immunization of producers. Obtained pilot batches of the enhanced anti-rabies immunoglobulin, complying with normative requirements to commercial formulations, testify to the effectiveness of the developed biotechnological and methodological procedures, as well as of the designed engineering-manufacturing project documentation

Optimization of Specifications for Scaled-Up Fixed Rabies Virus Cultivation (“Moscow 3253” Strain) in Vero Cell Culture

/cell, using maintenance media 199 with admixture of 0.1 % human serum albumin or 2 % bovine serum. Optimum media volume in the roll-bottle for fixed rabies virus strain, “Moscow 3253”, cultivation is 200-400 ml. It depends upon the proliferating surface area. Specifications stated above provide for the obtainment of culture liquid with rabies virus titer - 1:256 - 1:512, if assayed in ELISA. This cultural virus is recommended as a basis for immunization material obtainment with a view to produce anti-rabies immunoglobulin from equine blood serum

Experimental Substantiation of the Possibility to Use Finite Cell Line CHO-K1 for Determination of Specific Activity of Components of Chemical Cholera Vaccine

Objective was to experimentally substantiate the possibility to use the finite cell line CHO-K1 for measuring specific activity of cholera toxin and component of the vaccine choleragen-anatoxin in the process of chemical cholera vaccine manufacturing. Materials and methods. The studies involved the finite cell line CHO-K. The registration of results of bio-indication method was performed visually with the help of inverted microscope and photometrically - in colorimetric test for the assessment of metabolic activity of the cells at the wave length of 595 nm. Results and discussion. The proposed method allows for determining the toxin-production activity of Vibrio cholerae 569B strain during submerged cultivation in bioreactor and specific activity of choleragen-anatoxin by anatoxin binding measuring using cell cultures. The results correlate with the data obtained using intradermal Craig’s technique, GM1-ELISA and radial passive immune hemolysis (RPIH). Introduction of cell culture method into practice will provide for significant decrease in the volumes of usage of animals at the stages of manufacturing of chemical bivalent cholera vaccine

Development of an in-house reference standard for anti-rabies immunoglobulin potency, to be used in the virus neutralisation test in a Vero cell culture

The development and use of new methods of quality control of medicines involve the use of a lot of reference materials in quality control testing. Specialists of the Russian Research Antiplague Institute “Microbe” have proposed an alternative methodological approach to determination of potency of anti-rabies immunoglobulin in cell culture, which requires the development of an in-house reference standard (RS) certified against the biological reference preparation (BRP) of the European Pharmacopoeia human rabies immunoglobulin. The aim of the study was to develop and evaluate the metrological characteristics of an in-house RS for anti-rabies immunoglobulin potency, to be used in the virus neutralisation test in a Vero cell culture. Materials and methods: The following materials were used in the study: equine rabies immunoglobulin, Vero continuous cell culture, fixed rabies virus (Moscow 3253Vero strain), human rabies immunoglobulin BRP of the European Pharmacopoeia. The potencies of the candidate in-house RS and rabies immunoglobulin samples were determined in the neutralisation test in cell culture. The results were recorded using a fluorescent microscope. Statistical processing was carried out in accordance with general chapter 1.1.0014.15 of the State Pharmacopoeia of the Russian Federation, 14th edition. Results: the certified value of the in-house RS potency was 180.8±18.8 IU/mL. The confidence limits were determined at the 0.95 probability level. The shelf life of the in-house RS is 1.5 years (when stored according to the sanitary regulation SanPiN 3.3686-21). The certified in-house RS was assigned with the number 41-01-20. A set of technical and operational documentation was developed and approved for the in-house RS. The developed in-house RS can be used for in vitro determination of anti-rabies immunoglobulin potency, expressed in international units, to confirm its compliance with the product specification file. Conclusions: the authors developed an in-house RS for anti-rabies immunoglobulin potency, to be used in the virus neutralisation test in cell culture, certified against the human rabies immunoglobulin BRP of the European Pharmacopoeia

Биоэтические аспекты совершенствования производства антирабического иммуноглобулина в России

The main objective of the present research was to review the studies that look into ways of improving production of anti-rabies immunoglobulin in terms of bioethical principles: ensuring patients’ right to receive quality pharmaceutical care, and compliance with the 3R principles. At the same time, compliance with bioethical principles should contribute to the improvement of production technology and the product quality, which is especially important for antirabies immunoglobulin due to the existing high demand for it. The paper analyses the current trends in avoidance of animal use in the production of rabies immunoglobulin. It summarises the main methods of production of serum products for post-exposure prophylaxis of rabies. The example of heterologous rabies immunoglobulin is used to substantiate the need to improve quality control of drugs by following the 3R principles. The paper highlights the potential use of cell cultures for determination of rabies immunoglobulin specific activity. The authors formulated the objectives that include development and use of pyrogen detection methods which do not involve animal use and are consistent with the current pharmacopoeial standards. They assessed the possibility and feasibility of removing Abnormal Toxicity Test for heterologous rabies immunoglobulin in accordance with the current international trends. The formulated objectives imply optimisation of production of heterologous rabies immunoglobulin in Russia in order to improve the quality of antirabies measures. The objectives include higher production volumes to ensure the availability of the product to patients, reduction of the product reactogenicity by using cell-culture technologies for obtaining rabies antigen, as well as development and implementation of in vitro test methods for product quality control in terms of Specific activity, Pyrogenicity, and Abnormal toxicityОсновной целью работы явилась оценка исследований, направленных на развитие производства антирабического иммуноглобулина, с точки зрения биоэтических принципов: обеспечение права пациента на получение качественной фармацевтической помощи и соответствия концепции 3R. При этом следование биоэтическим принципам должно способствовать совершенствованию технологии производства и повышению качества лекарственного средства, что особенно актуально в отношении препарата антирабического иммуноглобулина вследствие его высокой востребованности. В статье проведен анализ современных тенденций по исключению животных в технологии производства антирабического иммуноглобулина. Показаны основные современные направления получения сывороточных препаратов для постэкспозиционной профилактики бешенства. На примере препарата гетерологичного антирабического иммуноглобулина обоснована необходимость совершенствования контроля качества лекарственных средств путем следования принципам 3R. Показан потенциал применения клеточных культур при определении специфической активности антирабического иммуноглобулина. Определены задачи по разработке и применению методов контроля содержания пирогенных примесей без использования животных в соответствии с актуальными фармакопейными документами. Проведена оценка возможности и целесообразности исключения показателя «Аномальная токсичность» в отношении гетерологичного антирабического иммуноглобулина в соответствии с современными международными тенденциями. Определены задачи совершенствования российского производства гетерологичного антирабического иммуноглобулина, направленные на улучшение качества обеспечения антирабической помощи, включающие увеличение объемов производства для обеспечения доступности препарата пациентам, снижение реактогенности препарата за счет получения рабического антигена с применением культуральных технологий, а также разработку и внедрение методов in vitro для проведения контрольных исследований качества препарата по показателям «Специфическая активность», «Пирогенность», «Аномальная токсичность»

Divalent EuRh2Si2 as a reference for the Luttinger theorem and antiferromagnetism in trivalent heavy-fermion YbRh2Si2

Application of the Luttinger theorem to the Kondo lattice YbRh2Si2 suggests that its large 4f-derived Fermi surface (FS) in the paramagnetic (PM) regime should be similar in shape and volume to that of the divalent local-moment antiferromagnet (AFM) EuRh2Si2 in its PM regime. Here we show by angle-resolved photoemission spectroscopy that paramagnetic EuRh2Si2 has a large FS essentially similar to the one seen in YbRh2Si2 down to 1 K. In EuRh2Si2 the onset of AFM order below 24.5 K induces an extensive fragmentation of the FS due to Brillouin zone folding, intersection and resulting hybridization of the Fermi-surface sheets. Our results on EuRh2Si2 indicate that the formation of the AFM state in YbRh2Si2 is very likely also connected with similar changes in the FS, which have to be taken into account in the controversial analysis and discussion of anomalies observed at the quantum critical point in this system