BioNanoAdhesion: atomic force microscopy study of the electrostatic properties of pyridine-and imidazole-based polycationic surfaces

Self-assembled monolayers of pyridine- and imidazole-based disulfides are currently being produced on low roughness gold surfaces. The electrostatic interaction between these surfaces and an atomic force microscope cantilever, modified with a silica microparticle, will subsequently be investigated as a function of environmental pH. The results can be used towards the development of improved nanoparticulate non-viral gene delivery vectors

Analysis of Emergency Situations When Working with Pathogenic Biological Agents within the Framework of Risk-Oriented Approach

The aim – based on the analysis of accidents when working with pathogenic biological agents (PBA) of pathogenicity groups I–II, draw conclusions about the causes of their occurrence and formulate recommendations for improving biological safety measures to reduce the risk of accidents.Materials and methods. The subject of the study was the data on accidents that happened during the work with PBA, stated in protocols of the commission for monitoring compliance with biological safety requirements of the Volgograd Research Anti-Plague Institute over the period of 1986–2020. Assessed were the type of emergency, their number, main causes and prerequisites for occurrence, professional category of a worker who participated in an accident.Results and discussion. During the specified period 3 types of accidents were recorded: accidents with spraying, accidents with skin lesion, accidents without spraying. There were no accidents with damage to the insulating suit and the pneumatic suit during the entire period under investigation. Of the total number of accidents, 42.85 % of cases were associated with skin lesion due to the bite of an experimental animal due to its incorrect fixation during infection, feeding, care, or due to autopsy of animals. Spillage accidents were recorded in 42.85 %; accidents without spraying amounted to 14.2 %. The categories of employees who made the greatest number of accidents have been identified: laboratory assistants – 39.2 % of cases, researcher officers – 14.2 %, disinfectors – 14.2 %. The causes of accidents and the prerequisites contributing to their realization have been pinpointed. The main ways and measures to reduce the risks of emergency situations for personnel when working with pathogens of particularly dangerous infectious diseases are put forward

Study of Protective Properties of Gentamicin in Liposome-Entrapped and Free Forms in Case of Aerogenic Melioidosis Infection

Presented are data on investigation of protective properties of free and liposome-entrapped forms of gentamicin against aerogenic infection caused by melioidosis agent. Comparative study identified that immobilization of gentamicin into liposomes increased substantially the ED50 of the preparation. This, probably, can be related to higher sorbtion of liposomal preparation by parenchymal organs including lungs

EMERGENCY PROPHYLAXIS OF EXPERIMENTAL MELIOIDOSIS USING SYNTHETIC IMMUNOMODULATORS AND HETEROLOGOUS VACCINES

Melioidosis is a particularly dangerous infection caused by Burkholderia pseudomallei , against which a vaccine has not yet been created. In this regard, the development of effective treatment regimens and emergency prevention of melioidosis is very relevant. To improve the effectiveness of emergency prophylaxis of melioidosis, synthetic peptides (bestim, imunofan) and thiopoietin preparation glutoxim were used when combined with the antibiotic doxycycline. In addition, in experiments on white mice, the ability of heterologous vaccines (plague and tularemia), used in the emergency prevention mode, to increase the resistance of animals to melioidosis infection was assessed. It was shown that the most effective was imunofan, which, when combined with doxycycline, increased by 20% the survival rate of 5LD50 Burkholderia pseudomallei infection and significantly increased the average life span of mice infected with 5-12 LD50 (p < 0.05). The efficiency of use for stimulation of non-specific resistance to melioidosis of a heterologous plague vaccine EV, once administered 1 day prior to infection, protected 90% of mice from 6 LD50 Burkholderia pseudomallei and 60% - with an increase in the infectious dose of the pathogen of melioidosis up to 15 LD50. The same level of protection from melioidosis was provided by a 3 day course of antibiotic therapy with doxycycline. It was concluded that the tularemia vaccine is not suitable for immunostimulation in melioidosis due to its high residual virulence and reactogenicity

Application of Cytokines and Synthetic Peptides for Increase in Immunogenicity of Melioidosis Antigens

B. pseudomallei 100 resistance (61.5 % of survived animals). It was concluded that it is a good practice to include bestim in the schedule of complex immunization against melioidosis

ОСОБЕННОСТИ ЛИОФИЛИЗАЦИИ НАНОЛИПОСОМАЛЬНОГО ПРЕПАРАТА

The conditions of lyophilization of nanoliposomes with encapsulated gentamicin (liposomal gentamicin) were studied. A mode of its safe lyophilization was suggested. A program for eliminating adverse factors was developed. It includes smooth increase of temperature from -70°C (freezing temperature) to room temperature (22±2)°C and gradual reduction of vacuum from 30 to 10 Pa without jumps and drops. The characteristics of the labile nanoliposomal drugs were not lost. The suggested program consisted of 10 steps allowing computer control to attain a slow and uniform increase in the temperature of the frozen product. The precise control of pressure in the chamber was provided by a system of automatic regulation of vacuum supplied with the equipment. After the rehydration the lyophilized preparations completely restored their original shape and properties.Изучены условия лиофилизации нанолипосом с инкапсулированным гентамицином (липосомальный гентамицин). Предложен мягкий технологический режим лиофилизации по разработанной программе автоматического управления параметрами. Предлагаемая программа состоит из 10 шагов для достижения медленного и равномерного повышения температуры замороженного продукта. Для устранения неблагоприятных факторов в программе, предусмотрено плавное увеличение температуры от -70°С (температура замораживания) до комнатной температуры (22±2)°С и постепенное снижение вакуума от 30 до 10 Па без скачков и перепадов. Точный контроль давления в камере обеспечивается системой автоматического регулирования вакуума, входящего в комплект поставки оборудования. После регидратации лиофилизированные препараты полностью восстановили свою первоначальную форму и свойства

Status of RF system for VEPP-5 damping ring

The paper presents the RF system of VEPP-5 damping ring created at BINP Novosibirsk. The RF system operates at 700 MHz and consists of the generator based on KU-393 klystron, transmitting waveguide with wave-to-coax adapters, accelerating cavity, and control system. HOM cavities are damped with resistive loads to eliminate the beam instability. Parameters and results of cold measurement tests and high power level tests are presented.Представлена ВЧ-система накопителя-охладителя для ВЭПП-5, созданная в БИЯФ, Новосибирск. ВЧ-система работает на частоте 700 МГц и состоит из генератора на клистроне КУ-393,передающего волновода с коаксиально-волноводными переходами, ускоряющего резонатора и системы управления и контроля. Для устранения пучковой неустойчивости высшие моды резонатора подавлены с помощью резистивных нагрузок. Приведены параметры и результаты холодных измерений и горячих испытаний ВЧ-системы.Представлено ВЧ-система нагромаджувача-охолоджувача для ВЕПП-5, що створена в БІЯФ, Новосибірськ. ВЧ-система працює на частоті 700 МГц і складається з генератора на клістроні КУ-393, передаючого хвилеводу з коаксіально-хвилеводними переходами, прискорюючого резонатора і системи керування і контролю. Для усунення пучкової нестійкості вищі моди резонатора подавлені за допомогою резистивних навантажень. Наведено параметри і результати холодних вимірів і гарячих випробувань ВЧ- системи

Features of lyophilization of a nanoliposomal drug

The conditions of lyophilization of nanoliposomes with encapsulated gentamicin (liposomal gentamicin) were studied. A mode of its safe lyophilization was suggested. A program for eliminating adverse factors was developed. It includes smooth increase of temperature from -70°C (freezing temperature) to room temperature (22±2)°C and gradual reduction of vacuum from 30 to 10 Pa without jumps and drops. The characteristics of the labile nanoliposomal drugs were not lost. The suggested program consisted of 10 steps allowing computer control to attain a slow and uniform increase in the temperature of the frozen product. The precise control of pressure in the chamber was provided by a system of automatic regulation of vacuum supplied with the equipment. After the rehydration the lyophilized preparations completely restored their original shape and properties

Results of Tests of Disinfecting Materials in Regard to Melioidosis and Glanders Agents

Objective of the work was to conduct tests of disinfectants against pathogens of melioidosis and glanders. Materials and methods. 10 strains of the causative agent of melioidosis, 4 strains of the glanders pathogen, and 5 strains of B. thailandensis were studied. All of them possessed biochemical, morphological, tinctorial, cultural and enzymatic properties typical of the respective species. The following disinfectants were used in the study: alkyldimethylbenzylammonium chloride (Sigma-Aldrich, USA), glutaraldehyde, chloramine B, hydrogen peroxide medical, MD-1 (Medical Disinfection LLC, Russia), CAT-18 (LLC Satellite, Russia), SAT-19 (Satellite LLC, Russia), ODS-15 (Satellite LLC, Russia), Ecotab-Active (Novodez JSC, Russia), Septodez-Forte (Novodez, JSC Russia). As test objects, tiles, ceramics, linoleum, painted wood, lining oilcloth, linen with and without sick discharge, dishes with and without food residues, medical products made of glass, plastic, rubber, silicone and metal were used. The criterion for the activity of the disin¬fectant was the lack of growth of microorganisms on solid and liquid nutrient media. To achieve statistical reliability, all tests were performed three times. Results and discussion. The conducted studies allow us to recommend B. pseudomallei 97 and B. thailandensis 264 as test strains for evaluating the bactericidal activity of new disinfectants in the laboratory against glanders and melioidosis infections. All studied disinfectants have a pronounced activity against glanders and melioidosis pathogens and can be used in concentrations from 0.1 to 2.5 %, for 60 minutes exposure