165 research outputs found
Approaches to Reduce Adverse Effect of Vaccinia Virus in Orally Immunized Mice
Objective of the investigation was to model the adverse action of vaccinia virus (VV), caused by oral immunization of mice and to evaluate efficacy of its reduction, using therapeutic and prophylactic drugs. Materials and methods. Virological and immunological research methods were used. Results and conclusions. Reproduced was pathological action of VV in the orally infected mice. The ability to reduce the side effect and protect mice from lethal infection was demonstrated by such preparations as Metisazon, Likopid, and NIOCH-14 orally administered in the investigated schemes. Moreover preliminary single oral immunization with TEOVak smallpox vaccine before oral infection with Neurovaccine-92 strain of VV also lowered pathogenic effect and protected mice against death. All the investigated schemes of drug administration did not affect the immune response if used alongside with TEOVak smallpox vaccine and can be deployed to develop safe schemes of primary oral vaccination against smallpox. In addition, such drugs as Ribomunil, Immudon, Ingavirin can be used as means to enhance the immune response to smallpox vaccines
Disinfection of Surfaces Contaminated with SARS-CoV-2 Coronavirus by UV Radiation of Low-Pressure Mercury-Vapour Lamp
The aim of the work was to determine the effective ultraviolet (UV) doses required for the disinfection of surfaces contaminated with the SARS-CoV-2 coronavirus using a low-pressure mercury lamp. Materials and methods. To carry out prompt disinfection of surfaces, a specially designed source of UV radiation with a power of 7.5 W at a wavelength of 254 nm in the form of a portable flashlight was employed, which has a high efficiency of UV radiation output and the possibility of long-term autonomous operation from a compact battery. In the studies, a suspension culture of the SARS-CoV-2 coronavirus with biological activity of 5.3â106 PFU/ml was used. The objects of testing were plastic Petri dishes (disposable) and office paper (grade C, density 80 g/m2 ). Results and discussion. Doses of UV radiation that provide disinfection of surfaces contaminated with the COVID-19 pathogen with an efficiency of 99.0 % (paper) to 99.95 % (plastic) have been determined. The results obtained make it possible to recommend a portable UV irradiator for use in the practice of preventive measures to combat the spread of the disease caused by the SARS-CoV-2 coronavirus
The Flow Cytometry Study of Cellular Immunity in Rhesus Monkeys after Experimental Infection with SARS CoV 2 Virus
Cellular immunity plays an important role in the pathogenesis and formation of protective immune defense against the SARSâCoVâ2 virus.The aim of the work was to study the cellular immunity of rhesus monkeys applying flow cytometry after experimental infection with the SARSâCoVâ2 virus.Materials and methods. Male rhesus monkeys were intranasally inoculated with the SARSâCoVâ2 virus, Isolate B strain and hCoV-19/Russia/SP48-1226/2020 strain (abbreviated name U-2), at a dose of 5.0 lg PFU. Using flow cytometry, the levels of 21 populations/subpopulations of mononuclear cells in the peripheral blood of animals were determined before experimental infection with the pathogen and on day 14 after infection. SARSâCoVâ2 coronavirus RNA was assessed using real-time polymerase chain reaction. Determination of the titer of virus-neutralizing antibodies to the SARSâCoVâ2 virus in the blood sera of animals was conducted through neutralization test evaluating the ability to suppress negative colonies.Results and discussion. Infection with Isolate B strain culture has led to an increase in the relative content of total T-lymphocytes (pË0.2), cytotoxic T-lymphocytes (pË0.1), as well as monocytes expressing the early activation marker CD25 (pË0.2). The decrease in levels has been observed for total B-lymphocytes (pË0.2) and T-helper cells (pË0.1). Infection with the U-2 strain culture revealed an increase in the relative content of monocytes expressing the early activation marker CD25 (pË0.2). Thus, for the first time in the Russian Federation, flow cytometry was used to study the cellular immunity of rhesus monkeys before and after experimental infection with the SARSâCoVâ2 virus. The obtained information can be used for studying the pathogenesis of SARSâCoVâ2 infection, course, and outcome of the disease, and developing strategies for vaccination and treatment
Hybrid integrated circuits for sound signal processing
Developed hybrid integrated circuit with rated supply voltage of 1,4 V, current consumption 0,7 mA and overall dimensions 8Ă4Ă3 mm provides soft processing of the audio signal in analog microelectronic equipment. Given its konstruktorsko-technological and electrical parameters
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