Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 52
Filter
1.
Sensors and Actuators B: Chemical ; : 131974, 2022.
Article in English | ScienceDirect | ID: covidwho-1815176

ABSTRACT

The outbreak of COVID-19 caused by SARS-CoV-2 urges the development of rapid and accurate diagnostic methods. Here, one high-sensitivity and point-of-care detection method based on magnetic SERS biosensors composed of Fe3O4-Au nanocomposite and Au nanoneedles array was developed to detect SARS-CoV-2 directly. Among, the magnetic Fe3O4-Au nanocomposite is applied to capture and separate virus from nasopharyngeal swabs and enhance the Raman signals of SARS-CoV-2. The magnetic SERS biosensor possessed high sensitivity by optimizing the Fe3O4-Au nanocomposite. More significantly, the on-site detection of inactivated SARS-CoV-2 virus was achieved based on the magnetic SERS biosensor with ultra-low limitation of detection of 100 copies/mL during 15mins. Furthermore, the contaminated throat and nasal swabs samples were identified by support vector machine, and the diagnostic accuracy of 100% was obtained. The magnetic SERS biosensor combined with support vector machine provides giant potential as the point-of-care detection tool for SARS-CoV-2.

2.
Biomedicine & Pharmacotherapy ; 150:112997, 2022.
Article in English | ScienceDirect | ID: covidwho-1803595

ABSTRACT

Background This study aimed to investigate the seroreactivity of Coronavirus disease 2019 (COVID-19) vaccination and its adverse events among systemic lupus erythematosus (SLE) patients, rheumatoid arthritis (RA) patients, and healthy controls (HCs). Methods A total of 60 SLE patients, 70 RA patients and 35 HCs, who received a complete inactivated COVID-19 vaccine (Vero cells) regimen, were recruited in the current study. Serum IgG and IgM antibodies against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) were determined by using chemiluminescent microparticle immunoassay (CMIA). Results There were no significant differences regarding the seroprevalences of IgG and IgM antibodies against SARS-CoV-2, and the self-reported vaccination-related adverse events among SLE patients, RA patients and HCs. The inactivated COVID-19 vaccines appeared to be well-tolerated and moderately immunogenic. In addition, case-only analysis indicated that in SLE patients, the disease manifestation of rash and anti-SSA autoantibody were associated with seroprevalence of IgG antibody against SARS-CoV-2, whereas the uses of ciclosporin and leflunomide had influence on the seroprevalence of IgM antibody against SARS-CoV-2. In RA patients, rheumatoid factor (RF) appeared to be associated with the seroprevalence of IgG antibody against SARS-CoV-2. Conclusion Our study reveals that the seroprevalences of IgG and IgM antibodies against SARS-CoV-2 and vaccination-related adverse effects are similar among SLE, RA and HCs, suggesting that COVID-19 vaccine is safe and effective for SLE and RA patients to prevent from the pandemic of COVID-19.

3.
Signal Transduct Target Ther ; 7(1): 114, 2022 Apr 05.
Article in English | MEDLINE | ID: covidwho-1778593

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of novel coronavirus disease (COVID-19). The neutralizing monoclonal antibodies (mAbs) targeting the receptor-binding domain (RBD) of SARS-CoV-2 are among the most promising strategies to prevent and treat COVID-19. However, SARS-CoV-2 variants of concern (VOCs) profoundly reduced the efficacies of most of mAbs and vaccines approved for clinical use. Herein, we demonstrated mAb 35B5 efficiently neutralizes both wild-type (WT) SARS-CoV-2 and VOCs, including B.1.617.2 (delta) variant, in vitro and in vivo. Cryo-electron microscopy (cryo-EM) revealed that 35B5 neutralizes SARS-CoV-2 by targeting a unique epitope that avoids the prevailing mutation sites on RBD identified in circulating VOCs, providing the molecular basis for its pan-neutralizing efficacy. The 35B5-binding epitope could also be exploited for the rational design of a universal SARS-CoV-2 vaccine.


Subject(s)
Antibodies, Monoclonal , Antibodies, Viral , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Antibodies, Monoclonal/chemistry , Antibodies, Viral/chemistry , COVID-19 , Cryoelectron Microscopy , Humans , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology
4.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-330371

ABSTRACT

Population antibody response is believed to be important in selection of new variant viruses. We identified that SARS-CoV-2 infections elicit a population immune response mediated by a lineage of VH1-69 germline antibodies. The representative antibody R1-32 targets a novel semi-cryptic epitope defining a new class of RBD targeting antibodies. Binding to this non-ACE2 competing epitope leading to spike destruction impairing virus entry. Based on epitope location, neutralization mechanism and analysis of antibody binding to spike variants we propose that recurrent substitutions at 452 and 490 are associated with immune evasion of this population antibody response. These substitutions, including L452R found in the Delta variant, disrupt interaction mediated by the VH1-69 specific hydrophobic HCDR2 to impair antibody-antigen association allowing variants to escape. Lacking 452/490 substitutions, the Omicron variant is sensitive to this class of antibodies. Our results provide new insights into SARS-CoV-2 variant genesis and immune evasion.

5.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-330164

ABSTRACT

Objectives: Since the outbreak of coronavirus disease 2019 (COVID-19), it has caused serious casualties worldwide. In recent months, the virus has mutated into an increasingly infectious form (Delta variant) and spread rapidly. Methods In the current study, we analyzed the clinical, epidemiological and viral genetic characteristics of the first four imported Delta cases in Anhui Province, China. Results The four imported Delta cases developed chest inflammation, tissue damage and recovered after admission, the serum high-sensitivity C-reactive protein (hs-CRP) and CRP levels showed a first increasing and then decreasing trend. The changes of hs-CRP /CRP and serum neutralizing antibodies (Nab) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) levels were associated with the regression of chest lesions. The combination of genetic sequencing and epidemiological analysis suggested that the SARS-CoV-2 delta variant infection of these four patients may originate from Russia. Conclusions Our study found the certain correlations of serum hs-CRP/CRP and Nab levels with the occurrence, development and outcome of COVID-19 delta variant, suggesting that monitoring hs-CRP/CRP and Nab levels of COVID-19 delta variant patients at hospital admission may be useful for understanding the severity of patients’ current conditions.

6.
Environ Res ; 211: 113055, 2022 Mar 04.
Article in English | MEDLINE | ID: covidwho-1719722

ABSTRACT

To better understand the change characteristics and reduction in organic carbon (OC) and elemental carbon (EC) in particulate matter (PM) with a diameter of ≤2.5 µm (PM2.5) driven by the most stringent clean air policies and pandemic-related lockdown measures in China, a comprehensive field campaign was performed to measure the carbonaceous components in PM2.5 on an hourly basis via harmonized analytical methods in the Beijing-Tianjin-Hebei and its surrounding region (including 2 + 26 cities) from January 1 to December 31, 2020. The results indicated that the annual average concentrations of OC and EC reached as low as 6.6 ± 5.7 and 1.8 ± 1.9 µg/m3, respectively, lower than those obtained in previous studies, which could be attributed to the effectiveness of the Clean Air Action Plan and the impact of the COVID-19-related lockdown measures implemented in China. Marked seasonal and diurnal variations in OC and EC were observed in the 2 + 26 cities. Significant correlations (p < 0.001) between OC and EC were found. The annual average secondary OC levels level ranged from 1.8-5.4 µg/m3, accounting for 37.7-73.0% of the OC concentration in the 2 + 26 cities estimated with the minimum R squared method. Based on Interagency Monitoring of Protected Visual Environments (IMPROVE) algorithms, the light extinction contribution of carbonaceous PM to the total amount reached 21.1% and 26.0% on average, suggesting that carbonaceous PM played a less important role in visibility impairment than did the other chemical components in PM2.5. This study is expected to provide an important real-time dataset and in-depth analysis of the significant reduction in OC and EC in PM2.5 driven by both the Clean Air Action Plan and COVID-19-related lockdown policies over the past few years, which could represent an insightful comparative case study for other developing countries/regions facing similar carbonaceous PM pollution.

7.
Front Med (Lausanne) ; 9: 829273, 2022.
Article in English | MEDLINE | ID: covidwho-1715010

ABSTRACT

Detection of serum-specific SARS-CoV-2 antibody has become a complementary means for the identification of coronavirus disease 2019 (COVID-19). As we already know, the neutralizing antibody titers in patients with COVID-19 decrease during the course of time after convalescence, whereas the duration of antibody responses in the convalescent patients has not been defined clearly. In the current study, we collected 148 serum samples from 37 confirmed COVID-19 cases with different disease severities. The neutralizing antibodies (Nabs), IgM and IgG against COVID-19 were determined by CLIA Microparticle and microneutralization assay, respectively. The time duration of serum titers of SARS-CoV-2 antibodies were recorded. Our results indicate that IgG (94.44%) and Nabs (89.19%) can be detected at low levels within 190-266 days of disease onset. The findings can advance knowledge regarding the antibody detection results for COVID-19 patients and provide a method for evaluating the immune response after vaccination.

8.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-325011

ABSTRACT

The pandemic outbreak of coronavirus disease 2019 (COVID-19) across the world has led to millions of infection cases and caused a global public health crisis. Current research suggests that SARS-CoV-2 is a highly contagious coronavirus that spreads rapidly through communities. To understand the mechanisms of viral replication, it is imperative to observe coronavirus viral replicase, a huge protein complex comprising up to 16 viral nonstructural and associated host proteins, which is the most promising antiviral target for inhibiting viral genome replication and transcription. Recently, several components of the viral replicase complex in SARS-CoV-2 have been solved to provide a basis for the design of new antiviral therapeutics. Here, we report the crystal structure of the SARS-CoV2 nsp7-8 tetramer, which comprises two copies of each protein representing nsp7’s full-length and the C-terminus of nsp8 owing to N-terminus proteolysis during the process of crystallization. We also identified a long helical extension and highly flexible N-terminal domain of nsp8, which is preferred for interacting with single-stranded nucleic acids.

9.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-324820

ABSTRACT

Background: COVID-19 is a newly emerging disease caused by a novel coronavirus (SARS-CoV-2), which spread globally in early 2020. Asymptomatic carriers of the virus contribute to the propagation of this disease, and the existence of asymptomatic infection has caused widespread fear and concern in the control of this pandemic. Methods: : In this study, we investigated the origin and transmission route of SARS-CoV-2 in Anhui’s two clusters, analyzed the role and infectiousness of asymptomatic patients in disease transmission, and characterized the complete spike gene sequences in the Anhui strains. Results: : We conducted an epidemiological investigation of two clusters caused by asymptomatic infections sequenced the spike gene of viruses isolated from 12 patients. All cases of the two clusters we investigated had clear contact histories, both from Wuhan, Hubei province. The viruses isolated from two outbreaks in Anhui were found to show a genetically close link to the virus from Wuhan. In addition, new single nucleotide variations were discovered in the spike gene. Conclusions: : Both clusters may have resulted from close contact and droplet-spreading and asymptomatic infections were identified as the initial cause. We also analyzed the infectiousness of asymptomatic cases and the challenges to the current epidemic to provided information for the development of control strategies.

10.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-324174

ABSTRACT

Background: Recently, investments in the construction of medical resources have been increasing annually China, and consequently, the allocation of these resources has improved. However, the outbreak of covid-19 in 2020 highlights the problems in the distribution of medical institutions. After the occurrence of public health emergencies, the joint action of different levels of medical and health institutions can bring the role of urban medical and health system into full play. Therefore, after a global public health emergency, the study of medical institution distribution needs to be reconsidered. Methods: : With the continuous application and development of GIS, the application of GIS in civil planning is relatively mature, and research investigating distribution has been conducted in depth. Based on this foundation, this paper analyzes the factors impacting distribution, such as the transportation system, land use characteristics and personal factors, by a weighted spatial separation model of a representative city in a cold region in China. Results: : A weighted spatial separation model was built and applied to comprehensively consider several factors affecting accessibility, including the spatial coverage separation, the service areas separation, the road network separation, the population separation and the weather separation. To calculate the accessibility of medical institutions using a weighted spatial separation model, Harbin was chosen as a case study. The accessibility of medical institutions was analyzed. Conclusions: : The accessibility of medical institutions in this representative cold city in China was comparatively analyzed in this paper through theoretical research, software computations/simulations and model analysis based on the GIS paradigm. This study will help optimize the layout of medical institutions and improve medical equality. Trial registration: An ethics review and approval for this study was not required according to the local legislation and institutional requirements.

11.
Matter ; 5(2): 694-709, 2022 Feb 02.
Article in English | MEDLINE | ID: covidwho-1670871

ABSTRACT

The current COVID-19 pandemic urges us to develop ultra-sensitive surface-enhanced Raman scattering (SERS) substrates to identify the infectiousness of SARS-CoV-2 virions in actual environments. Here, a micrometer-sized spherical SnS2 structure with the hierarchical nanostructure of "nano-canyon" morphology was developed as semiconductor-based SERS substrate, and it exhibited an extremely low limit of detection of 10-13 M for methylene blue, which is one of the highest sensitivities among the reported pure semiconductor-based SERS substrates. Such ultra-high SERS sensitivity originated from the synergistic enhancements of the molecular enrichment caused by capillary effect and the charge transfer chemical enhancement boosted by the lattice strain and sulfur vacancies. The novel two-step SERS diagnostic route based on the ultra-sensitive SnS2 substrate was presented to diagnose the infectiousness of SARS-CoV-2 through the identification standard of SERS signals for SARS-CoV-2 S protein and RNA, which could accurately identify non-infectious lysed SARS-CoV-2 virions in actual environments, whereas the current PCR methods cannot.

12.
Frontiers in public health ; 9, 2021.
Article in English | EuropePMC | ID: covidwho-1652412

ABSTRACT

Coronavirus disease 2019 (COVID-19) spread throughout China in January 2020. To contain the virus outbreak, the Chinese government took extraordinary measures in terms of public policy, wherein accurate and timely dissemination of information plays a crucial role. Despite all of the efforts toward studying this health emergency, little is known about the effectiveness of public policies that support health communication during such a crisis to disseminate knowledge for self-protection. Particularly, we focus on the accuracy and timeliness of knowledge dissemination on COVID-19 among people in remote regions—a topic largely omitted in existing research. In February 2020, at the early-stages of the COVID-19 outbreak, a questionnaire survey was carried out. In total, 8,520 participants from seven less economically developed provinces situated in the borderlands of China with large ethnic minority groups responded. We analyzed the data through poisson regression and logistic regression analyses. We found that (1) people in remote regions of China obtained accurate information on COVID-19. Further, they were able to take appropriate measures to protect themselves. (2) Result from both descriptive analysis and multivariable regression analysis revealed that there is no large difference in the accuracy of information among groups. (3) Older, less educated, and rural respondents received information with a significant delay, whereas highly educated, younger, urban residents and those who obtained information through online media were more likely to have received the news of the outbreak sooner and to be up to date on the information. This research provides evidence that disadvantage people in remote regions obtained accurate and essential information required to act in an appropriate manner in responses to the COVID-19 outbreak. However, they obtained knowledge on COVID-19 at a slower pace than other people;thus, further improvement in the timely dissemination of information among disadvantage people in remote regions is warranted.

13.
PLoS One ; 17(1): e0261216, 2022.
Article in English | MEDLINE | ID: covidwho-1622335

ABSTRACT

BACKGROUND: The global epidemic of novel coronavirus pneumonia (COVID-19) has resulted in substantial healthcare resource consumption. Since patients' hospital length of stay (LoS) is at stake in the process, an investigation of COVID-19 patients' LoS and its risk factors becomes urgent for a better understanding of regional capabilities to cope with COVID-19 outbreaks. METHODS: First, we obtained retrospective data of confirmed COVID-19 patients in Sichuan province via National Notifiable Diseases Reporting System (NNDRS) and field surveys, including their demographic, epidemiological, clinical characteristics and LoS. Then we estimated the relationship between LoS and the possibly determinant factors, including demographic characteristics of confirmed patients, individual treatment behavior, local medical resources and hospital grade. The Kaplan-Meier method and the Cox Proportional Hazards Model were applied for single factor and multi-factor survival analysis. RESULTS: From January 16, 2020 to March 4, 2020, 538 human cases of COVID-19 infection were laboratory-confirmed, and were hospitalized for treatment, including 271 (50%) patients aged ≥ 45, 285 (53%) males, and 450 patients (84%) with mild symptoms. The median LoS was 19 (interquartile range (IQR): 14-23, range: 3-41) days. Univariate analysis showed that age and clinical grade were strongly related to LoS (P<0.01). Adjusted multivariate analysis showed that the longer LoS was associated with those aged ≥ 45 (Hazard ratio (HR): 0.74, 95% confidence interval (CI): 0.60-0.91), admission to provincial hospital (HR: 0.73, 95% CI: 0.54-0.99), and severe illness (HR: 0.66, 95% CI: 0.48-0.90). By contrast, the shorter LoS was linked with residential areas with more than 5.5 healthcare workers per 1,000 population (HR: 1.32, 95% CI: 1.05-1.65). Neither gender factor nor time interval from illness onset to diagnosis showed significant impact on LoS. CONCLUSIONS: Understanding COVID-19 patients' hospital LoS and its risk factors is critical for governments' efficient allocation of resources in respective regions. In areas with older and more vulnerable population and in want of primary medical resources, early reserving and strengthening of the construction of multi-level medical institutions are strongly suggested to cope with COVID-19 outbreaks.


Subject(s)
COVID-19/epidemiology , Adult , Age Factors , China/epidemiology , Female , Hospitalization , Humans , Length of Stay/statistics & numerical data , Male , Middle Aged , Retrospective Studies , Risk Factors , Survival Analysis
14.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-293463

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of novel corona virus disease (COVID-19). The neutralizing monoclonal antibodies (mAbs) targeting the receptor binding domain (RBD) of SARS-CoV-2 are among the most promising strategies to prevent and treat COVID-19. However, SARS-CoV-2 variants of concern (VOCs) profoundly reduced the efficacies of most of mAbs and vaccines approved for clinical use. Herein, we demonstrated mAb 35B5 efficiently neutralizes both wild-type (WT) SARS-CoV-2 and VOCs, including B.1.617.2 (delta) variant, in vitro and in vivo . Cryo-electron microscopy (cryo-EM) revealed that 35B5 neutralizes SARS-CoV-2 by targeting a unique epitope that avoids the prevailing mutation sites on RBD identified in circulating VOCs, providing the molecular basis for its pan-neutralizing efficacy. The 35B5-binding epitope could also be exploited for the rational design of a universal SARS-CoV-2 vaccine.

15.
Biosens Bioelectron ; 197: 113771, 2022 Feb 01.
Article in English | MEDLINE | ID: covidwho-1536447

ABSTRACT

Due to the similar clinical symptoms of influenza (Flu) and coronavirus disease 2019 (COVID-19), there is a looming infection threat of concurrent Flu viruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this work, we introduce a customized isothermal amplification integrated lateral flow strip (LFS) that is capable performing duplex reverse transcription-recombinase polymerase amplification (RT-RPA) and colorimetric LFS in a sequential manner. With customized amplification primer sets targeted to SARS-CoV-2 (opening reading frame 1a/b and nucleoprotein genes) and Flu viruses (Flu A and Flu B), the platform allows the rapid and simultaneous visual screening of SARS-CoV-2 and Flu viruses (Flu A and Flu B) without cross reactivity, false positives, and false negatives. Moreover, it maximally eases the detection, reduces the detection time (1 h), and improves the assay performance to detect as low as 10 copies of the viral RNA. Its clinical application is powerfully demonstrated with 100% accuracy for evaluating 15 SARS-CoV-2-positive clinical samples, 10 Flu viruses-positive clinical samples, and 5 negative clinical samples, which were pre-confirmed by standard qRT-PCR. We envision this portable device can meet the increasing need of online monitoring the serious infectious diseases that substantially affects health care systems worldwide.


Subject(s)
Biosensing Techniques , COVID-19 , Influenza, Human , Humans , Influenza, Human/diagnosis , Nucleic Acid Amplification Techniques , SARS-CoV-2 , Sensitivity and Specificity
16.
Mol Biomed ; 1(1): 14, 2020 Nov 30.
Article in English | MEDLINE | ID: covidwho-1515460

ABSTRACT

The global pandemic of COVID-19 has attracted extensive drug searching interets for the new coronavirus SARS-CoV-2. Although currently several of clinically used "old" drugs have been repurposed to this new disease for the urgent clinical investigation, there is still great demand for more effective therapies for the anti-infections. Here we report the discovery that an "old" drug Emetine could potently inhibit SARS-CoV-2 virus replication and displayed virus entry blocking effect in Vero cells at low dose. In addition, Emetine could significantly reduce the lipopolysaccharide (LPS) induced interleukin-6 (IL-6) protein level and moderately reduce the tumor necrosis factor (TNF-α) protein level in the M1 polarized THP-1 macrophages. In vivo animal pharmacokinetics (PK) study revealed that Emetine was enriched in the lung tissue and had a long retention time (over 12 h). With 1 mg/kg single oral dose, the effective concentration of Emetine in lung was up to 1.8 µM (mice) and 1.6 µM (rats) at 12 h, which is over 200-fold higher than the EC50 of the drug. The potent in vitro antiviral replication efficacy and the high enrichment in target tissue, combining with the well documented safety profiles in human indicate that low dose of Emetine might be a potentially effective anti-SARS-CoV-2 infection therapy.

17.
J Med Virol ; 93(10): 5998-6007, 2021 10.
Article in English | MEDLINE | ID: covidwho-1432442

ABSTRACT

In the context of the coronavirus disease 2019 pandemic, we investigated the epidemiological and clinical characteristics of a young patient infected by avian influenza A (H5N6) virus in Anhui Province, East China, and analyzed genomic features of the pathogen in 2020. Through the cross-sectional investigation of external environment monitoring (December 29-31, 2020), 1909 samples were collected from Fuyang City. It was found that the positive rate of H5N6 was higher than other areas obviously in Tianma poultry market, where the case appeared. In addition, dual coinfections were detected with a 0.057% polymerase chain reaction positive rate the surveillance years. The virus was the clade 2.3.4.4, which was most likely formed by genetic reassortment between H5N6 and H9N2 viruses. This study found that the evolution rates of the hemagglutinin and neuraminidase genes of the virus were higher than those of common seasonal influenza viruses. The virus was still highly pathogenic to poultry and had a preference for avian receptor binding.


Subject(s)
COVID-19/epidemiology , Influenza A virus/isolation & purification , Influenza in Birds/virology , Influenza, Human/virology , Animals , Child, Preschool , China , Female , Genome, Viral/genetics , Humans , Influenza A virus/classification , Influenza A virus/genetics , Influenza, Human/diagnosis , Mutation , Phylogeny , Poultry/virology , Reassortant Viruses/classification , Reassortant Viruses/genetics , Reassortant Viruses/isolation & purification , SARS-CoV-2 , Viral Proteins/genetics
18.
Front Immunol ; 12: 715464, 2021.
Article in English | MEDLINE | ID: covidwho-1430698

ABSTRACT

The mutants resulted from the ongoing SARS-CoV-2 epidemic have showed resistance to antibody neutralization and vaccine-induced immune response. The present study isolated and identified two novel SARS-CoV-2 neutralizing antibodies (nAbs) from convalescent COVID-19 patients. These two nAbs (XG81 and XG83) were then systemically compared with nine nAbs that were reconstructed by using published data, and revealed that, even though these two nAbs shared targeting epitopes on spike protein, they were different from any of the nine nAbs. Compared with XG81, XG83 exhibited a higher RBD binding affinity and neutralization potency against wild-typed pseudovirus, variant pseudoviruses with mutated spike proteins, such as D614G, E484Q, and A475V, as well as the authentic SARS-CoV-2 virus. To explore potential broadly neutralizing antibodies, heavy and light chains from all 18 nAbs (16 published nAbs, XG81 and XG83) were cross-recombined, and some of the functional antibodies were screened and studied for RBD binding affinity, and neutralizing activity against pseudovirus and the authentic SARS-CoV-2 virus. The results demonstrated that several recombined antibodies had a more potent neutralization activity against variant pseudoviruses compared with the originally paired Abs. Taken together, the novel neutralizing antibodies identified in this study are a likely valuable addition to candidate antibody drugs for the development of clinical therapeutic agents against SARS-CoV-2 to minimize mutational escape.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Broadly Neutralizing Antibodies/immunology , Broadly Neutralizing Antibodies/therapeutic use , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/therapeutic use , Antibodies, Viral/genetics , Antibodies, Viral/therapeutic use , Antibody Affinity/immunology , B-Lymphocytes/immunology , Broadly Neutralizing Antibodies/genetics , COVID-19/immunology , COVID-19/therapy , Cell Line , Epitopes/immunology , Humans , Immunotherapy/methods , Neutralization Tests , SARS-CoV-2/drug effects
19.
International Journal of Environmental Research and Public Health ; 17(8), 2020.
Article in English | CAB Abstracts | ID: covidwho-1409550

ABSTRACT

This paper is aimed to document the observed social exclusion and discrimination in the outbreak of COVID-19 across the world and inside of China. Discrimination and social exclusion has occurred in various forms, while 25.11% of respondents overseas experienced discrimination in the breakout of COVID-19, and 90% of respondents inside of China exhibited discriminatory attitudes. The discrimination and social exclusion also lead to a range of damaging social outcomes. Thus, this is an urgent call for the inclusiveness in policy and media in the face of this public health emergency.

20.
Sci Total Environ ; 805: 150248, 2022 Jan 20.
Article in English | MEDLINE | ID: covidwho-1401853

ABSTRACT

Since the outbreak of COVID-19 pandemic, the lockdown policy across the globe has brought improved air quality while fighting against the coronavirus. After the closure, urban air quality was subject to emission reduction of air pollutants and rebounded to the previous level after the potency period of recession. Different response patterns exhibit divergent sensitivities of urban resilience in regard to air pollution. In this paper, we investigate the post-lockdown AQI values of 314 major cities in China to analyse their differential effects on the influence factors of urban resilience. The major findings of this paper include: 1) Cities exhibit considerable range of resilience with their AQI values which are dropped by 21.1% per day, took 3.97 days on average to reach the significantly decreased trough point, and reduced by 49.3% after the lockdown initiatives. 2) Mega cities and cities that locate as the focal points of transportation for nearby provinces, together with those with high AQI values, were more struggling to maintain a good air quality with high rebounds. 3) Urban resilience shows divergent spatial sensitivities to air pollution controls. Failing to consider multi-dimensional factors besides from geomorphological and economical activities could lead to uneven results of environmental policies. The results unveil key drivers of urban air pollution mitigation, and provide valuable insights for prediction of air quality in response to anthropogenic interference events under different macro-economic contexts. Research findings in this paper can be adopted for prevention and management of public health risks from the perspective of urban resilience and environmental management in face of disruptive outbreak events in future.


Subject(s)
Air Pollutants , Air Pollution , COVID-19 , Air Pollutants/analysis , Air Pollution/analysis , China/epidemiology , Cities , Communicable Disease Control , Environmental Monitoring , Humans , Pandemics , Particulate Matter/analysis , SARS-CoV-2
SELECTION OF CITATIONS
SEARCH DETAIL