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1.
Vestnik Rossijskoj Voenno-Medicinskoj Akademii ; 24(4):675-682, 2022.
Article in English | Scopus | ID: covidwho-20239844

ABSTRACT

Given the rapid spread of coronavirus disease 2019 (COVID-19) globally, test systems are needed for its diagnosis, timely treatment, and introduction of quarantine measures. In the shortest possible time, a diagnostic system based on real-time reverse-transcription polymerase chain reaction to detect the ribonucleic acid of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal and oropharyngeal smears was developed and registered. The method determines the nucleocapsid and small-membrane protein genes and the human PGK1 gene, acting as internal control reactions. The nucleotide sequences of SARS-CoV-2 were analyzed, and primers were selected. The conditions for carrying out real-time reverse-transcription polymerase chain reaction and the composition of a set of reagents were set. The diagnostic sensitivity and specificity of the kit were tested on biological samples, with the addition of inactivated SARSCoV-2. The high analytical characteristics of the developed set of reagents were demonstrated, with a sensitivity of at least 103 GE/mL and a specificity of 100%, and no false-positive or false-negative results were recorded. The high specificity of the test system was shown on a representative sample of genetic materials of respiratory viral pathogens. Clinical and laboratory tests of the diagnostic "SARS-CoV-2 test” were conducted in the N.F. Gamalei National Research Center for Epidemiology and Microbiology. A set of reagents for the detection of ribonucleic acid of SARS-CoV-2 through on real-time reverse-transcription polymerase chain reaction for in vitro diagnostics "SARS-CoV-2 test” was registered in the Russian Federation as a medical device (Registration certificate no. RZN 2020/10632, dated 06/03/2020). The article can be used under the CC BY-NC-ND 4.0 license © Authors, 2022.

2.
Extreme Medicine ; - (2):19-25, 2021.
Article in English | EMBASE | ID: covidwho-2324329

ABSTRACT

The development of coronavirus infection outbreak into a pandemic, coupled with the lack of effective COVID-19 therapies, is a challenge for the entire pharmaceutical industry. This study aimed to assess the treatment and preventive efficacy of the amino acid-peptide complex (APC) in male Syrian hamsters infected with SARSCoV-2 (intranasal administration of 26 mul of the virus culture, titer of 4 x 104 TCD50/ml). In a modeled COVID-19 case, APC administered for treatment and preventive purposes reduced lung damage. Compared to the positive control group, test group had the lung weight factor 15.2% smaller (trend), which indicates a less pronounced edema. Microscopic examination revealed no alveolar edema, atypical hypertrophied forms of type II alveolocytes, pulmonary parenchyma fibrinization. The macrophage reaction intensified, which is probably a result of the APC-induced activation of regenerative processes in the lung tissues. Spleens of the animals that received APC for therapeutic and preventive purposes were less engorged and had fewer hemorrhages. The decrease of body weight of the test animals that received APC for treatment and prevention was insignificant (p < 0.05), which indicates a less severe course of COVID-19. Administered following a purely therapeutic protocol, APC proved ineffective against SARS-CoV-2 post-infection. Thus, APC-based drug used as a therapeutic and preventive agent reduces pulmonary edema and makes morphological signs of lung tissue damage less pronounced in male Syrian hamsters infected with SARS-CoV-2.Copyright © Extreme Medicine.All right reserved.

3.
Vopr Virusol ; 67(5): 403-413, 2022 11 19.
Article in Russian | MEDLINE | ID: covidwho-2275592

ABSTRACT

INTRODUCTION: Convalescent COVID-19 patients have various signs of central nervous system damage, including those directly associated with SARS-CoV-2. Hence, studies of SARS-COV-2 related morphological changes in neocortex are particularly relevant for understanding the mechanisms of their formation and development of approaches to preclinical evaluation of the effectiveness of antiviral drugs. The purpose of the research is a longitudinal study of the ultrastructural alterations in Syrian hamsters neocortex after experimental SARS-CoV-2 infection. MATERIALS AND METHODS: Male Syrian hamsters weighing 80100 g, aged 4 to 6 weeks, were infected with 26 l SARS-CoV-2 intranasally with 4104 TCD50/ml of viral particles. The animals were euthanized on days 3, 7 or 28 post-infection, the brain was extracted with the cortex excision. The material analysis was performed using transmission electron microscopy. RESULTS AND DISCUSSION: On day 3 post-infection, the number of moderately hyperchromic neurons in neocortex increased, while by the day 7 the number of apoptotic cells significantly increased. Simultaneously, an increased signs of neuronophagy and representation of atypical glia were observed. Increased number of altered oligodendrocytes was observed on day 28 post-infection. Viral invasion was accompanied by changes in neocortical cells since day 3 post-infection, such as transformation of their nucleus, the rough endoplasmic reticulum and the Golgi vesicles as well as microvascular spasm with perivascular edema. CONCLUSION: As a result of electron microscopic study, the ultrastructural alterations in neocortex were described in an experimental model of SARS-CoV-2 infection. The findings can be used to identify the mechanisms of infection pathogenesis and to search for the new directions in development of medicines.


Subject(s)
COVID-19 , Coronaviridae , Neocortex , Severe acute respiratory syndrome-related coronavirus , Cricetinae , Animals , Male , SARS-CoV-2 , Mesocricetus , Longitudinal Studies , Electrons , Disease Models, Animal
4.
Siberian Journal of Life Sciences and Agriculture ; 14(1):436-451, 2022.
Article in English | Scopus | ID: covidwho-1964628

ABSTRACT

The year 2020 was heavily influenced by the COVID-19 pandemic in all areas of human and social life. Today, it is difficult to imagine sectors of the economy that would not be affected by the pandemic, but the pharmaceutical industry and pharmaceutical companies are facing serious challenges. On the one hand, the pharmaceutical industry is forced to function in restrictions, like any other type of business in a pandemic, and on the other hand, it is forced to ensure uninterrupted production and supply of medicines, quickly increase their production, and strategically plan its activities in the post-pandemic world. All phases of pharmaceutical companies are affected by the pandemic, from the production and procurement of raw materials to research and development and doctor-patient interaction processes. The pharmaceutical industry, along with the health care system, has been at the epicenter of the global fight against the pandemic and its aftermath. In addition to new opportunities for the pharmaceutical industry in the fight against COVID-19, such as vaccine development and clinical trials of medical drugs to treat COVID-19, the pandemic has harmed the supply chain and production of herbal medicinal raw materials. The global pharmaceutical industry has faced the consequences of the closure of China’s customs borders for quarantine, as China is currently the leader in the production of medicinal pharmaceutical raw materials, accounting for about 40% of the world’s production of medicinal plant pharmaceutical raw materials. China has gained a leading position in the pharmaceutical raw materials industry due to its high production volume and low cost. Closed borders and quarantine-induced lockdown predetermined serious threats in the supply chain for the needs of pharmaceutical production, which was automatically reflected in rising logistics and freight prices. The presented study reviews the current state of the pharmaceutical herbal medicine industry and justifies the priorities of its development in post-pandemic conditions. © 2022, Science and Innovation Center Publishing House. All rights reserved.

5.
Vopr Virusol ; 66(6): 442-451, 2022 01 08.
Article in Russian | MEDLINE | ID: covidwho-1623041

ABSTRACT

INTRODUCTION: Verification of histological changes in respiratory system using Syrian (golden) hamsters (Mesocricetus auratus) as experimental model is an important task for preclinical studies of drugs intended for prevention and treatment of the novel coronavirus infection COVID-19.The aim of this work was to study pathological changes of pulmonary tissue in SARS-CoV-2 (Coronaviridae: Coronavirinae: Betacoronavirus; Sarbecovirus) experimental infection in Syrian hamsters. MATERIAL AND METHODS: Male Syrian hamsters weighting 80-100 g were infected by intranasal administration of culture SARS-CoV-2 at dose 4 × 104 TCID50/ml (TCID is tissue culture infectious dose). Animals were euthanatized on 3, 7 and 14 days after infection, with gravimetric registration. The viral load in lungs was measured using the polymerase chain reaction (PCR). Right lung and trachea tissues were stained with hematoxylin-eosin and according to Mallory. RESULTS AND DISCUSSION: The highest viral replicative activity in lungs was determined 3 days after the infection. After 7 days, on a background of the decrease of the viral load in lungs, a pathologically significant increase of the organ's gravimetric parameters was observed. Within 3 to 14 days post-infection, the lung histologic pattern had been showing the development of inflammation with a succession of infiltrative-proliferative, edematousmacrophagal and fibroblastic changes. It was found that initial changes in respiratory epithelium can proceed without paranecrotic interstitial inflammation, while in the formation of multiple lung parenchyma lesions, damage to the epithelium of bronchioles and acinar ducts can be secondary. The appearance of epithelioid large-cell metaplastic epithelium, forming pseudoacinar structures, was noted as a pathomorphological feature specific to SARS-CoV-2 infection in Syrian hamsters. CONCLUSION: As a result of the study, the specific features of the pathology of the respiratory system in SARSCoV-2 infected Syrian hamsters were described. These findings are of practical importance as reference data that can be used for preclinical studies to assess the effectiveness of vaccines and potential drugs.


Subject(s)
COVID-19 , Lung/pathology , Lung/virology , Mesocricetus , Animals , Coronaviridae , Disease Models, Animal , Inflammation , Male , Mesocricetus/immunology , Mesocricetus/virology , SARS-CoV-2
6.
Clinical and Experimental Morphology ; 10(4):25-34, 2021.
Article in Russian | Scopus | ID: covidwho-1614524

ABSTRACT

Introduction. Amid the pandemic of the new coronavirus infection COVID-19, experimental models for screening both newly developed vaccines and drugs, and the already registered active pharmaceutical ingredients tested for new indications are in high demand. The registration of changes in biometric and morphological parameters that are significant for the investigative pathology can be an optimal screening tool for antiviral drugs and vaccines to treat COVID-19. In this regard, the purpose of this study was to describe the changes over time of organ and tissue changes using a biological model of a SARS-CoV-2-associated infection in the golden hamsters Mesocricetus auratus. Materials and methods. We performed the study in golden hamsters Mesocricetus auratus weighing 80–100 g. The animals were infected through intranasal administration of a culture of SARS-CoV-2 virus containing 4 × 104 TCID50 /mL. We recorded the animals’ weight before the infection and during the next 14 days and measured the specific gravity of the internal organs and the degree of their moisture saturation on days 3, 7, and 14 after the infection. Additionally, tissue samples were fixed in 10% neutral formalin;the preparation of histological specimens was performed according to the standard procedure. Statistical data processing was carried out using non-parametric tests. Results. In the model of SARS-CoV-2 infection in Mesocricetus auratus, we observed the manifestation of the infectious disease after 3 days. The most pronounced pathological changes in the overall health status of the animals and in the histology of internal organs were seen 7 days after the infection. We determined the weight loss and significant deviations in gravimetric coefficients of lungs, heart, spleen, and kidneys to be the indicators revealing the infectious disease course changes over time. Histologic evaluation showed typical changes in the SARS-CoV-2-associated visceral damage: the formation of polymorphonuclear cell infiltrates in the lung interalveolar septa and patchy dystrophic changes in the neurocytes of the brain screen-type centers with the demyelination of the commissural nerve guides. The detected pathological manifestations corresponded in time to an increase in the virus replicative activity in the lungs. Conclusion. The experimental model of the SARS-CoV-2-associated infection in golden hamsters Mesocricetus auratus can be recommended for screening experimental (preclinical) studies of the promising drugs’ efficacy for pathogenetic and etiotropic therapy of COVID-19. © 2021, MDV Group. All rights reserved.

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