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Abstract This work aimed to show which treatments showed efficacy against coronavirus disease 2019 (COVID-19); therefore, the results of 37 clinical trials started in 2020 and completed in 2021 are reviewed and discussed here. These were selected from databases, excluding vaccines, computational studies, in silico, in vitro, and those with hyperimmune sera from recovered patients. We found 34 drugs, one vitamin, and one herbal remedy with pharmacological activity against symptomatic COVID-19. They reduced mortality, disease progression, or recovery time. For each treatment, the identifier and type of trial, the severity of the disease, the sponsor, the country where the trial was conducted, and the trial results are presented. The drugs were classified according to their mechanism of action. Several drugs that reduced mortality also reduced inflammation in the most severe cases. These include some that are not considered anti-inflammatory, such as Aviptadil, pyridostigmine bromide, anakinra, imatinib, baricitinib, and bevacizumab, as well as the combination of ivermectin, aspirin, dexamethasone, and enoxaparin. Nigella sativa seeds with honey have also been reported to have therapeutic activity. On the other hand, tofacitinib, novaferon with ritonavir, and lopinavir were also effective, as well as in combination with antiviral therapies such as danoprevir with ritonavir. The natural products colchicine and Vitamin D3 were only effective in patients with mild-to-moderate COVID-19, as was hydroxychloroquine. Drug repositioning has been the main tool in the search for effective therapies by expanding the pharmacological options available to patients.
Resumen El objetivo del presente trabajo fue conocer qué tratamientos mostraron efectividad contra COVID-19, para lo cual se revisan y discuten los resultados de 37 estudios clínicos iniciados durante 2020 y concluidos en 2021. Estos fueron seleccionados de bases de datos, excluyendo vacunas, estudios computacionales, in silico, in vitro y con sueros hiperinmunes de pacientes recuperados. Se documentaron 34 fármacos, una vitamina y un remedio herbolario, con actividad farmacológica ante COVID-19 sintomático. Estos redujeron la mortalidad, el progreso de la enfermedad, o el tiempo de recuperación. Para cada tratamiento se presenta identificador y tipo de estudio, la gravedad de la enfermedad, patrocinador, país donde se realizó, así como sus resultados. Los fármacos se clasificaron de acuerdo con su mecanismo de acción. Varios fármacos que redujeron la mortalidad también disminuyeron la inflamación en los casos más graves. Esto incluyendo algunos no considerados antiinflamatorios, como el aviptadil, el bromuro de piridostigmina, el anakinra, el imatinib, el baricitinib y el bevacizumab, así como la combinación de ivermectina, aspirina, dexametasona y enoxaparina. También se reportaron con actividad terapéutica las semillas de Nigella sativa con miel. Además, resultaron efectivos el tofacitinib, el novaferón con ritonavir y lopinavir, así como los antivirales en terapias combinadas como el danoprevir con ritonavir. Los productos naturales colchicina y vitamina D3, solo tuvieron actividad en los pacientes en estado leve a moderado de la COVID-19, así como la hidroxicloroquina. El reposicionamiento de fármacos fue la principal herramienta para buscar terapias efectivas ampliando las opciones farmacológicas accesibles a los pacientes.
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Objective To investigate the characteristics of blood routine,chest computed tomography(CT)imaging and short-term evolution of hemodialysis patients infected with Omicron variant of severe acute respiratory syndrom coronavirus 2(SARS-CoV-2).Methods A total of 204 patients diagnosed with Omicron variant infection in the First Hospital of Hohhot from September 2022 to September 2023 were retrospectively reviewed.Among them,89 patients with end-stage renal disease(ESRD)who were receiving hemodialysis were included in the hemo-dialysis group.The remaining 115 patients were control group,and the first blood routine results chest com-puted tomography(CT)imaging data were observed.Thirty-four patients in the hemodialysis group and 29 patients in the control group had complete pulmonary CT imaging data on the day of admission,5-6 days and 10-12 days after admission.The characteristics and chest CT scores of all cases were analyzed.Results 1)The percentage of monocytes,neutrophils,neutrophil/lymphocyte ratio and chest CT score of the hemo-dialysis group were higher than those of the control group,while the white blood cells,lymphocytes and lymphocyte percentage were lower than those of the control group.2)The positive rate of first chest CT was 49.4%in hemo-dialysis group and 35.7%in control group.3)The chest CT scores of the hemo-dialysis group and the control group on day 5 and day 6 were higher than those of first check.Chest CT was reexamined on days 10-12,and scores were higher in the hemo-dial-ysis group than in the control group.Conclusions Hemo-dialysis patients with COVID-19 have higher blood routine indexes,higher positive rate of lung CT and slower absorption than non-hemodialysis patients.
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Corona virus disease 2019(COVID-19)epidemic has been effectively controlled,but its related complications still cannot be ignored,especially the cardiovascular circulatory system is the active site of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Angiotensin-converting enzyme 2(ACE2)is a type Ⅰ transmembrane glycoprotein that is highly expressed in heart,kidney and testis.Spike protein of SARS-CoV-2 invades host cells by binding to the cell surface receptor ACE2.However,there are still many deficiencies in the clinical application of vaccines and drugs developed based on this target.As a molecular chaperone,cyclophilin A(CypA)promotes protein folding and T cell activation.CD147 is one of the most widely studied CypA receptors,and the interaction of CypA/CD147 plays an important role in the entry of SARS-CoV-2 into host cells.However,there are few reports on the invasion of SARS-CoV-2 into the cardiovascular system through the CypA/CD147 signaling pathway.Based on this,this article summarizes the previous research evidence and the research basis of the research group,and reviews the structure and function of CypA/CD147,the role of CypA/CD147 in cardiovascular disease,and the cardiovascular disease caused by SARS-CoV-2 targeting CypA/CD147 signal pathway,in order to provide reference for the diagnosis and treatment of the COVID-19 complicated with cardiovascular system diseases.
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Objective To evaluate the characteristics of different antigen-specific T cell immune responses to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)after inoculation with 2 doses of SARS-CoV-2 inactivated vaccine for 12 months.Methods Fifteen healthy adults were enrolled in this study and blood samples collected at 12 months after receiving two doses of SARS-CoV-2 inactivated vaccine.The level and phenotypic characteristics of SARS-CoV-2 antigen-specific T lymphocytes were detected by activation-induced markers(AIM)based on polychromatic flow cytometry.Results After 12 months of inoculation with 2 doses of SARS-CoV-2 inactivated vaccine,more than 90%of adults had detectable Spike and Non-spike antigen-specific CD4+ T cells immune responses(Spike:14/15,P=0.0001;Non-spike:15/15,P<0.0001).80%of adults had detectable Spike and Non-spike antigen-specific CD8+ T cells immune responses(Spike:12/15,P=0.0463;Non-spike:12/15,P=0.0806).Antigen-specific CD4+ T cells induced by SARS-CoV-2 inactivated vaccination after 12 months were composed of predominantly central memory(CM)and effector memory 1(EM1)cells.On the other hand,in terms of helper subsets,antigen-specific CD4+ T cells mainly showed T helper 1/17(Th1/17)and T helper 2(Th2)phenotypes.Conclusions SARS-CoV-2 inactivated vaccination generates durable and extensive antigen-specific CD4+ T cell memory responses,which may be the key factor for the low proportion of severe coronavirus disease 2019(COVID-19)infection in China.
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Objective:To analyze the specific immunoglobulin G (IgG) antibodies level in the population after the coronavirus disease 2019 (COVID-19) pandemic in Henan Province.Methods:A total of 5 178 peripheral venous blood samples were collected from 10 districts (counties) in Henan Province according to the national seroepidemiological survey program for COVID-19, and the method of cluster random sampling was adopted from March 6 to 15, 2023. Descriptive analysis was used for the basic data, history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, SARS-CoV-2 infection of the respondents. The specific IgG antibody of SARS-CoV-2 was detected using chemiluminescence method. Statistical analysis was performed by using rank sum test, Kruskal Wallis test, and Dunn′s test.Results:The overall positive rate of SARS-CoV-2-specific IgG antibody was 83.35%(4 316/5 178). There were statistically significant differences in the specific IgG antibodies against SARS-CoV-2 produced by people of different sexes, different ages, infected or not, vaccinated or not, and vaccinated with different doses of SARS-CoV-2 vaccine ( Z=3.60, H=195.32, Z=6.10, 18.08, H=382.70, respectively, all P<0.001). The specific IgG antibodies produced by unvaccinated+ uninfected group, unvaccinated+ infected group, vaccinated+ uninfected group, and vaccinated+ infected group were 3.54(0.98, 11.00), 60.65(2.33, 84.80), 133.00(59.80, 173.00), and 142.00(98.30, 176.00), respectively. And the difference was statistically significant( H=354.62, P<0.001). The specific IgG antibodies of uninfected people increased with the increase of inoculum times( H=287.00 and 98.48, both P<0.001). The specific IgG antibodies of people who were not infected with SARS-CoV-2 in the groups of whose interval from the last inoculation of SARS-CoV-2 vaccine to blood collection was less than three months, three to six months and more than six months were 171.86(156.04, 196.57), 71.71(17.08, 110.38) and 132.14(57.59, 172.25), respectively, and the difference was statistically significant ( H=19.93, P<0.001). Among them, the absolute difference between the less than three months group and the three to six months group was statistically significant ( Z=3.67, P<0.001), and the absolute difference between the less than three months group and the more than six months group was statistically significant ( Z=3.47, P<0.001). The specific IgG antibodies level in the less than three months group was the highest. Conclusions:There is a certain correlation between the number of SARS-CoV-2 vaccine doses and the specific IgG antibodies level in uninfected people. The specific IgG antibodies could maintain a high level for three months after immunization.
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The corona virus disease 2019(COVID-19)in 2019 has shown a global pandemic status in a short time since its outbreak, and many variants of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)were highly infectious and pathogenic. SARS-CoV-2 may infect tissue cells through the mediation of angiotensin-converting enzyme-2(ACE2)and transmembrane serine protease 2(TMPRSS2), leading to different diseases. Clinically, respiratory, cardiovascular, and gastrointestinal systems diseases are relatively common; many patients also seek medical attention based on eye symptoms as their main complaint. Compared with severe systemic diseases, eye-related symptoms are easily overlooked. This article reviews the pathogenesis and cases of various eye diseases related to SARS-CoV-2, aiming to enhance clinicians' attention to SARS-CoV-2-related eye diseases, avoid delaying the disease and causing irreversible loss of vision, and provide new ideas for the prevention and treatment of eye diseases.
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Since 2019, severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection has been widespread in the world, causing about 770 million infecting and 6.9 million deaths. Vaccines against SARS-CoV-2 infection have become the main way to prevent the severe SARS-CoV-2. The use of SARS-CoV-2 vaccine has substantial protection against the serious consequences of SARS-CoV-2 infection, but multiple systemic adverse reactions can occur after the use of SARS-CoV-2 vaccine. More and more studies have shown that SARS-CoV-2 vaccine caused lesions of ocular conjunctiva, cornea, sclera, uvea, retina and optic nerve tissue and resulted in damage to visual function. In this paper, the classification and characteristics of SARS-CoV-2 vaccines and related studies on ocular tissue lesions were reviewed, hoping to better understand the ocular adverse reactions of SARS-CoV-2 vaccine and provide some theoretical guidance for the prevention and treatment of ocular tissue damage caused by SARS-COV-2 vaccine.
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Coronavirus disease 2019(COVID-19)has been one of the most concerning public health events in recent years,seriously threatening the lives and health of people worldwide.COVID-19 vaccines are the most cost-effective measure to reduce the influence of severe acute respiratory syndrome coronavirus 2(SARS-COV-2)to the population.Therefore,countries actively develop and vaccinate COVID-19 vaccines,including recombinant protein vaccines,viral vector vaccines,inactivated vaccines,and mRNA vaccines,which occupy the primary market.With the enhancement of variants transmission ability and evasion immunity,the protective effect and durability of COVID-19 vaccines have become the current research hotspots.This paper presents a brief review of the progress of COVID-19 vaccines,intending to provide a reference for the development of COVID-19 vaccines.
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Objective To explore the efficacy and safety of recombinant human anti-severe acute respiratory syn-drome coronavirus 2(anti-SARS-CoV-2)monoclonal antibody injection(F61 injection)in the treatment of patients with coronavirus disease 2019(COVID-19)combined with renal damage.Methods Patients with COVID-19 and renal damage who visited the PLA General Hospital from January to February 2023 were selected.Subjects were randomly divided into two groups.Control group was treated with conventional anti-COVID-19 therapy,while trial group was treated with conventional anti-COVID-19 therapy combined with F61 injection.A 15-day follow-up was conducted after drug administration.Clinical symptoms,laboratory tests,electrocardiogram,and chest CT of pa-tients were performed to analyze the efficacy and safety of F61 injection.Results Twelve subjects(7 in trial group and 5 in control group)were included in study.Neither group had any clinical progression or death cases.The ave-rage time for negative conversion of nucleic acid of SARS-CoV-2 in control group and trial group were 3.2 days and 1.57 days(P=0.046),respectively.The scores of COVID-19 related target symptom in the trial group on the 3rd and 5th day after medication were both lower than those of the control group(both P＜0.05).According to the clinical staging and World Health Organization 10-point graded disease progression scale,both groups of subjects improved but didn't show statistical differences(P＞0.05).For safety,trial group didn't present any infusion-re-lated adverse event.Subjects in both groups demonstrated varying degrees of elevated blood glucose,elevated urine glucose,elevated urobilinogen,positive urine casts,and cardiac arrhythmia,but the differences were not statistica-lly significant(all P＞0.05).Conclusion F61 injection has initially demonstrated safety and clinical benefit in trea-ting patients with COVID-19 combined with renal damage.As the domestically produced drug,it has good clinical accessibility and may provide more options for clinical practice.
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Multisystem inflammatory syndrome in children is a disease related with severe acute respiratory syndrome corona-virus 2 infection,which can involve multiple system damage.Most cases included features of shock,cardiac dysfunction,gastrointestinal symptoms,significantly elevated markers of inflammation and cardiac damage,and positive test results for SARS-CoV-2 by serology.Although its clinical features overlap with Kawasaki disease,it is more likely to occur in older children and adolescents,and most of them need to be treated with intensive care and a variety of immunomodulators.At present,the pathogenesis and long-term prognosis of the disease need to be further studied.
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ObjectiveThis study explored the application of Yiqi Zengmian prescription as a vaccine adjuvant， aiming to provide a new scheme for the prevention and control of corona virus disease 2019（COVID-19） with traditional Chinese medicine （TCM）. By analyzing the compatibility and efficacy， this paper examines the compatibility effect of Yiqi Zengmian prescription， which is modified from the classic tonifying agent Si Junzitang， as a vaccine adjuvant. MethodUsing the Database of Ancient Classical Prescriptions， this paper analyzed the composition of Yiqi Zengmian prescription and probed into the theoretical basis for the compatibility of this prescription from the properties， medicine combination， and efficacy. Furthermore， the compatibility effect of this prescription with vaccines was analyzed. ResultAs a TCM prescription， Yiqi Zengmian prescription focuses on the lung and spleen and enhances the Qi in the two organs. The lung governs Qi movement. The body breathes fresh air through the lungs and exchanges the turbid gas in the lungs， and the gas circulates alternately in the lungs to ensure the normal breathing of the human body. The spleen governing transportation and transformation is the hub for Qi movement， and Qi is the embodiment of metabolic function. By regulating qi movement and enhancing the functions of Qi and blood， Yiqi Zengmian prescription can enhance the immunogenicity of the vaccine， which provides a theoretical basis for enhancing the immune effects of vaccines. ConclusionYiqi Zengmian prescription has the effects of replenishing Qi and invigorating spleen， regulating Qi and drying dampness， and enhancing immunity. The in-depth analysis of the TCM theory of Yiqi Zengmian prescription as a vaccine adjuvant and the results of clinical and laboratory studies suggest that Yiqi Zengmian prescription may enhance the induction of immune response after vaccination and maintain the immune memory. However， the mechanism of Yiqi Zengmian prescription in regulating the complex immune network remains to be elucidated.
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Multisystem inflammatory syndrome in children (MIS-C) is a complex syndrome characterized by multi-organ involvement that has emerged in the context of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak. The clinical presentation of MIS-C is similar to Kawasaki disease but predominantly presents with fever and gastrointestinal symptoms, and severe cases can involve toxic shock and cardiac dysfunction. Epidemiological findings indicate that the majority of MIS-C patients test positive for SARS-CoV-2 antibodies. The pathogenesis and pathophysiology of MIS-C remain unclear, though immune dysregulation following SARS-CoV-2 infection is considered a major contributing factor. Current treatment approaches for MIS-C primarily involve intravenous immunoglobulin therapy and symptomatic supportive care. This review article provides a comprehensive overview of the definition, epidemiology, pathogenesis, clinical presentation, diagnosis, treatment, and prognosis of MIS-C.
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Enfant , Humains , COVID-19 , SARS-CoV-2 , Pandémies , Syndrome de réponse inflammatoire généralisée/thérapieRésumé
Objectives: In December 2019, coronavirus disease 2019 (COVID-19) was first identified in Wuhan, China, as a respiratory tract infection causing symptoms, such as fever, chills, dry cough, fatigue, and shortness of breath. Despite the low mortality rate of COVID-19, patients with comorbidities such as hypertension, cardiovascular disease, and diabetes mellitus seem to be prone to more severe symptoms and to a higher mortality rate than others. Such patients are shown to benefit from usage of monoclonal antibodies. Casirivimab-imdevimab is a cocktail made up of two non-competing, neutralizing human immunoglobulin G1 antibodies that target the receptor binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein and block viral entry into human cells. We assessed the clinical profile and outcome of 42 patients who received the antibody cocktail. Materials and Methods: Casirivimab-imdevimab was administered to COVID-positive patients with mild severity. Forty-two patients who satisfied the inclusion criteria received casirivimab-imdevimab and were included in the study. Demographic and clinical data were tabulated in Microsoft Excel and statistics were run in OpenEpi software. Results: No adverse reactions were seen in any of the patients. Among the 42 patients, there were no deaths. Twentytwo (52.3%) patients improved, while 20 (47.6%) worsened after receiving the antibody cocktail. Out of 21 (50%) patients who did not have any comorbidity, 13 (30.9%) worsened after receiving the drug and 8 (19%) improved, while among those with comorbidities, 7 (16.6%) worsened and 14 (33.3%) improved (P < 0.05). Thirteen (30.9%) unvaccinated patients improved, while 14 (33.3%) worsened, whereas 6 (14.2%) fully vaccinated patients improved while only 2 (4.7%) worsened. Among the patients who were administered the cocktail within 5 days of onset of symptoms, 12 (28.5%) improved and 10 (23.8%) worsened, whereas among those who received the drug between 6 and 10 days of symptom onset, ten improved, and ten worsened. There was no statistically significant association between vaccination status and outcome, and infusion interval and outcome in these patients. Conclusion: None of the 42 patients developed any reaction to casirivimab-imdevimab. There were no deaths in the study population. About 52.3% of the patients improved and 47.6% worsened after receiving the cocktail. About 33.3% of the comorbid patients improved. There was no statistically significant association between vaccination status and outcome, and infusion interval and outcome in these patients.
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Background: Coronavirus 2019 infection (COVID 19) is an ongoing pandemic caused by pathogenic RNA viruses called severe acute respiratory syndrome coronavirus-2 (SARS-COV-2). It has affected people of all ages, with high morbidity and mortality among the elderly and immunocompromised population. Limited information is available on the effects of COVID-19 infection on pregnancy. Aim: To describe the histopathological changes in the placental tissue of SARS-CoV-2 infected term mothers with no comorbidities and to correlate with neonatal outcome. Materials and Methods: This observational study was conducted in the Department of Pathology, KMCH institute of health sciences and research, Coimbatore from May 1, 2020 to November 30, 2020 for 6 months. Placental tissues of all COVID-19-positive term mothers with no comorbidities were included in this study. Histopathological examination of placentae was carried out and clinical data of mothers and newborn babies were obtained from medical records. Results: Histopathological examination of 64 placental tissue of COVID-19 mothers showed predominantly the features of fetal vascular malperfusion like stem villi vasculature thrombus, villous congestion, and avascular villi. No significant correlation was obtained in comparison with parity and symptomatic status of the mothers. However, histopathological changes were more prominent among symptomatic patients. The newborn babies born to these mothers showed no adverse outcome. Conclusion: This study concluded that though COVID-19 infection in normal term pregnant women was associated with increased prevalence of features of fetal vascular malperfusion, there was no significant morbidity in the health status of both COVID-19 mothers and their neonates.
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Introduction: To assess the status of bi-directional screening for COVID-19, tuberculosis and diabetes among people attending Non-communicable Disease (NCD), Directly Observed Treatment Short-course (DOTS), and flu clinics of a secondary care hospital in rural northern India. Material and Methods: A cross?sectional, analytical study was conducted among the eligible (aged ?18 years) population who attended the study clinics in a rural sub-district hospital. In the flu clinic, consecutive patients were assessed for screening for TB (symptom-based) and diabetes (random blood sugar) and status of referral to DOTS and NCD clinics. Similarly, the screening for diabetes and COVID-19, Reverse Transcription-Polymerase Chain Reaction (RT-PCR) in the DOTS clinic, and TB and COVID-19 in the NCD clinic were assessed. The independent association of factors with COVID-19 positivity were assessed by calculating the adjusted prevalence ratios (aPR) at 95% confidence interval (CI). Results: Of the 405 people assessed, 279 (68.9%), 102 (25.2%), and 24 (5.9%) were from flu, NCD, and DOTS clinics, respectively. 26 (25.5%) and 22 (91.7%) of NCD and DOTS clinic patients underwent RT-PCR for COVID-19. TB screening in NCD and flu clinics was done among 4 (3.9%) and 7 (12.5%), respectively. A total of 23 (9.0%) were found positive for COVID-19, and no factors other than the presence of COVID-19 symptoms (aPR: 2.89; 95% CI: 1.33–6.29) had any independent association with COVID-19 positive status. Conclusion: The low screening for TB in NCD and flu clinics indicates the need to strengthen the implementation the TB-DM and TB-COVID-19 bidirectional screening. Similarly, the low screening or testing for COVID-19 in the NCD clinic can be improved by the implementation of systematic screening strategies like TB-DM bidirectional screening.
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Abstract BACKGROUND: Severe acute respiratory syndrome coronavirus 2 has several mechanisms of action related to inflammatory responses, especially in individuals diagnosed with obesity. This hyperinflammatory clinical profile resulting from the association between obesity and coronavirus disease 2019 (COVID-19) may be attenuated by regular physical activity. OBJECTIVE: The aim of this study was to review the evidence on the consequences of physical inactivity and physical activity on COVID-19 in patients with obesity. DESIGN AND SETTING: Narrative review at the Bahiana School of Medicine and Public Health in Salvador, Brazil. METHODS: We searched evidence on the association of COVID-19 with physical activity and obesity using the following keywords: "covid-19," "physical activity," and "obesity". The databases used were MEDLINE (PubMed), ScienceDirect, and Virtual Health Library. Studies published from 2019 to 2021 and available in Portuguese, English, and Spanish were included. The final search was conducted on September 26, 2021. RESULTS: We identified 661 studies in the database, among which 71 were considered for inclusion in the narrative review of the molecular aspects of COVID-19 and its relationship with physical activity and obesity. CONCLUSION: This literature review enabled the perception of the relationship between the molecular mechanisms of COVID-19 and obesity. Regular physical activity had various benefits for the inflammatory condition of the studied population, highlighting moderate-intensity.
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@#Abstract：Objective To prepare human monoclonal antibody against spike protein（S protein）of severe acute respiratory syndrome coronavirus 2（SARS⁃CoV⁃2）by using single B cell，and determine its neutralizing activity. Methods Venous blood with high antibody level was collected from people immunized with inactivated SARS⁃CoV⁃2 vaccine（Vero cells） twice，of which peripheral blood mononuclear cells（PBMCs）were isolated by lymphocyte stratified fluid and used to isolate single B cell expressing S protein antibody by magnetic beads coupled with S1 protein. Variable region genes of IgG heavy chain and light chain were amplified by nested PCR after reverse transcription of single B cell，which were connected with CMV promoter，IgG leader sequence，IgG constant region and polyA sequence by overlapping PCR to construct antibody linear expression cassette. Linear expression cassette of the heavy chain and light chain from the same B cell was transfected to HEK293T cells to express human monoclonal antibody of SARS⁃CoV⁃2 S protein. Immunoreactivity was detected by immuno⁃ fluorescence while neutralizing activity by pseudovirus neutralization test. Results A total of 26 monoclonal antibodies against SARS⁃CoV⁃2 S protein were expressed，which showed heavy chain and light chain protein bands of IgG antibody at
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@#Objective To evaluate the pharmacodynamics of human interferon(IFN)α1b against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron strain in vitro.Methods Total four drugs human IFNα1b bulk,human IFNα1b eye drops,human IFNα1b spray and Remdesivir were detected for cytotoxicity by CCK-8 assay.The inhibitory effect of human IFNα1b on SARS-CoV-2 Omicron strains(BA.5/BA.2/BA.1)was determined by qPCR.Results Human IFNα1b bulk of the maximum concentration(1 × 107IU/mL)and Remdesivir of the maximum concentration(150 μmol/L)did not achieve half cytotoxicity to Vero cells;The median cytotoxicity concentrations(CC_(50))of human IFNα1b eye drops and human IFNα1b sprays were 29 958 and 37 550 IU/mL,respectively,showing toxicity to Vero cells.The median effective concentrations(EC_(50))of human IFNα1b against virus strains BA.1,BA.2 and BA.5 after incubation for 2 h in advance were 9.30,13.38 and 12.33 IU/mL and those of Remdesivir were 0.314 7,0.291 0 and0.300 3 μmol/L.When incubation with virus simultaneously,the EC_(50)of human IFNα1b to BA.1,BA.2 and BA.5 were19.68,10.91 and 18.84 IU/mL and those of the control drug Remdesivir were 0.320 5,0.274 4 and 0.304 1 μmol/L,respectively.Conclusion At the cell level in vitro,human IFNα1b of very low activity showed a good inhibitory effect on SARS-CoV-2 Omicron strain,which was expected to be a clinical specific drug for the treatment of SARS-CoV-2 Omicron strain infection.
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@#Objective To construct a single-chain fragment variable(scFv)phage display library against receptor-binding domain(RBD)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spike protein(S)to screen specific scFv and identify the function.Methods m RNA was extracted from spleen cells of mice immunized with RBD protein and reversely transcribed into c DNA,with which as template,genes of the hight chain fragment of variable(VH)and light chain fragment of variable(VL)of scFv were amplified and then assembled into scFv gene fragment through splicing overlap extension PCR(SOE-PCR).The scFv gene fragment was inserted to phage vector to construct scFv phage display library.After four rounds of biopanning,the scFv gene with strong binding ability to RBD was screened and expressed recombinantly,purified and identified for biological activity.Results The constructed scFv phage library showed a titer of 6.0×10(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(334～353)),RBD9(S(334～353)),RBD9(S(439～458))and RBD13(S(439～458))and RBD13(S(499～518)).Homologous model of scFv constructed by online server SWISS-MODEL showed a good quality and was used for molecular docking.The interface at which scFv11 interacted with RBD only partially coincided with the interaction interface of human angiotensin converting enzyme 2(ACE2)and RBD,and the interaction interfaces of scFv12 and scFv25 with RBD were quite different from that of ACE2.Conclusion In this study,scFv specifically bound to SARS-Co V-2 RBD was screened and prepared through constructing scFv phage library against SARS-CoV-2 RBD,which provided experimental basis for further development of anti-SARS-CoV-2 drugs and detection reagents.
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@#Objective To prepare and verify a uniform antigen content detection kit for recombinant protein vaccines against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Methods Using goat anti-S protein polyclonal antibody prepared by National Institutes for Food and Drug Control(NIFDC) as coating antibody,one of four monoclonal antibodies(14C8,15F9,17A7 and 20D8)with high receptor-binding domain(RBD)binding activity and broad-spectrum resistance against major variants as HRP-labeled antibody,a uniform double-antibody sandwich ELISA kit for antigen content detection of recombinant SARS-CoV-2 vaccine was prepared,and the dilution of coating antibody(1∶125 ～ 1∶4 000)and enzymelabeled antibody(1∶250 ～ 1∶32 000)were optimized by chessboard titration. The specificity,linear range,accuracy,precision and durability of the kit were verified. The prepared uniform detection kits were distributed to 12 laboratories to detect15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions(including 11 batches of stock solutions designed with WT strain and 4 batches of designed with Beta,Gamma and Delta variants as reference sequence)from different expression systems(CHO cells,Pichia pastoris,Sf9 cells or E. coli)and target proteins(RBD or S protein)prepared by each laboratory.Results Monoclonal antibody 20D8 was used as the enzyme-labeled antibody with the optimal dilution of 1 : 4 000,and the optimal dilution of coating antibody was 1 : 500. The uniform detection kit showed no cross reaction with recombinant S protein of severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS). The first generation national standard for recombinant SARS-CoV-2 protein vaccine antigen(national standard for short)showed a concentration of 0. 16 ～ 2. 50 U/mL with a good linear relationship with A450/630,and the linear equation was:y = 0. 791 x-0. 100 4,R2= 0. 993 7;The recoveries of 0. 16 ～ 2. 50 U/mL national standard in 6 repeated tests were 95% ～ 104% and the coefficients of variation(CVs)were less than 15%;The CVs in 3 repeated tests by 2 experimenters at different time were 4. 4% ～6. 6% and the recoveries were in the range of 80% ～ 120% under different temperature and time conditions. The antigen content of 15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions showed good parallelism with the national standard. Conclusion The uniform detection kit for antigen content developed in this study had good specificity,accuracy,precision and durability,and might be used for the detection of antigen content of recombinant SARS-CoV-2 protein vaccines.