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1.
Frontiers in public health ; 10, 2022.
Article in English | EuropePMC | ID: covidwho-1872003

ABSTRACT

Background With promotion of COVID-19 vaccinations, there has been a corresponding vaccine hesitancy, of which older adolescents and young adults represent groups of particular concern. In this report, we investigated the prevalence and reasons for vaccine hesitancy, as well as potential risk factors, within older adolescents and young adults in China. Methods To assess these issues, an online survey was administered over the period from March 14 to April 15, 2021. Older adolescents (16–17 years old) and young adults (18–21 years old) were recruited nationwide from Wechat groups and results from a total of 2,414 respondents were analyzed. Socio-demographic variables, vaccine hesitancy, psychological distress, abnormal illness behavior, global well-being and social support were analyzed in this report. Results Compared to young adults (n = 1,405), older adolescents (n = 1,009) showed higher prevalence rates of COVID-19 vaccine hesitancy (16.5 vs. 7.9%, p < 0.001). History of physical diseases (p = 0.007) and abnormal illness behavior (p = 0.001) were risk factors for vaccine hesitancy among older adolescents, while only a good self-reported health status (p = 0.048) was a risk factor for young adults. Concerns over COVID-19 vaccine side effects (67.1%) and beliefs of invulnerability regarding infection risk (41.9%) were the most prevalent reasons for vaccine hesitancy. Providing evidence on the vaccine reduction of COVID-19 infection risk (67.5%), ensuring vaccine safety (56.7%) and the low risk of side effects (52.7%) were the most effective persuasions for promoting vaccinations. Conclusion In China, older adolescents showed a higher prevalence for vaccine hesitancy than that of young adults. Abnormal illness behavior and history of physical diseases were risk factors for vaccine hesitancy among these older adolescents, while social support represents an important factor which could help to alleviate this hesitancy.

2.
Front Public Health ; 10: 819062, 2022.
Article in English | MEDLINE | ID: covidwho-1862691

ABSTRACT

Background: More than 200 countries are experiencing the coronavirus disease (COVID-19) pandemic. COVID-19 vaccination strategies have been implemented worldwide, and repeat COVID-19 outbreaks have been seen. The purpose of this study was to investigate the impact of COVID-19 vaccination on the reduction of perceived anxiety and the association between public anxiety and antibody testing intention during the COVID-19 pandemic. Methods: Chinese adults aged 18 and over were surveyed using an anonymous online questionnaire in April and May 2021. The questionnaire collected sociodemographic characteristics, vaccination characteristics, perceived anxiety due to COVID-19, and attitudes toward future antibody testing after COVID-19 vaccination. Perceived anxiety was assessed on a visual analog scale (VAS). Multivariate logistic regression analysis was used to determine the factors influencing future antibody detection. Results: A total of 3,233 people were investigated, 3,209 valid questionnaires were collected, and the response rate was 99.3%. Of the 3,209 respondents, 2,047 were vaccinated, and 1,162 were unvaccinated. There was a significant difference in anxiety levels between vaccinated and unvaccinated respondents (24.9±25.4 vs. 50.0±33.1, respectively). With the local spread of COVID-19 in mainland China, the public anxiety VAS scores increased by 15.4±25.6 (SMD=120%) and 33.8±31.7 (SMD=49%) among vaccinated and unvaccinated respondents, respectively. Of the 2,047 respondents who were vaccinated, 1,626 (79.4%) thought they would accept antibody testing. Those who displayed more anxiety about acquiring COVID-19 disease were more likely to accept COVID-19 antibody testing. If the antibody test results showed protective antibodies, 1,190 (58.1%) were more likely to arrange travel plans in China, while 526 (25.7%) thought they would feel safer traveling abroad. Conclusion: COVID-19 vaccination strategies help reduce public anxiety. However, public anxiety may be elevated as the local transmission of COVID-19 occurs in mainland China, which is usually caused now by imported cases. Those who display more anxiety choose to have antibody testing. Improving the accessibility of COVID-19 antibody tests can help ease public anxiety and enhance the confidence of some people to participate in social activities.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adolescent , Adult , Antibodies, Viral , Anxiety , COVID-19/diagnosis , COVID-19/prevention & control , COVID-19 Testing , Humans , Pandemics , SARS-CoV-2 , Vaccination
3.
Small ; : e2200854, 2022 May 22.
Article in English | MEDLINE | ID: covidwho-1858927

ABSTRACT

The ongoing pandemic caused by severe acute respiratory syndrome coronavirus 2 is profoundly influencing the global healthcare system and people's daily lives. The high resource consumption of coronavirus disease 2019 (COVID-19) is resulting in insufficient surveillance of coinfection or resurgence of other critical respiratory epidemics, which is of public concern. To facilitate evaluation of the current coinfection situation, a microfluidic system (MAPnavi) is developed for the rapid (<40 min) and sensitive diagnosis of multiple respiratory viruses from swab samples in a fully sealed and automated manner, in which a nested-recombinase polymerase amplification and the CRISPR-based amplification system is first proposed to ensure the sensitivity and specificity. This novel system has a remarkably low limit of detection (50-200 copies mL-1 ) and is successfully applied to detect 171 clinical samples (98.5% positive predictive agreement; 100% negative predictive agreement), and the results identify 45.6% coinfection among clinical samples from patients with COVID-19. This approach has the potential to shift diagnostic and surveillance efforts from targeted testing for a high-priority virus to comprehensive testing of multiple virus sets and to greatly benefit the implementation of decentralized testing.

4.
Front Immunol ; 13: 869809, 2022.
Article in English | MEDLINE | ID: covidwho-1847173

ABSTRACT

Previous studies have shown that B.1.351 and other variants have extended the host range of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to mice. Sustained transmission is a prerequisite for viral maintenance in a population. However, no evidence of natural transmission of SARS-CoV-2 in wild mice has been documented to date. Here, we evaluated the replication and contact transmission of the B.1.351 variant in mice and rats. The B.1.351 variant could infect and replicate efficiently in the airways of mice and rats. Furthermore, the B.1.351 variant could not be transmitted in BALB/c or C57BL/6 mice but could be transmitted with moderate efficiency in rats by direct contact. Additionally, the B.1.351 variant did not transmit from inoculated Syrian hamsters to BALB/c mice. Moreover, the mouse-adapted SARS-CoV-2 strain C57MA14 did not transmit in mice. In summary, the risk of B.1.351 variant transmission in mice is extremely low, but the transmission risk in rats should not be neglected. We should pay more attention to the potential natural transmission of SARS-CoV-2 variants in rats and their possible spillback to humans.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Cricetinae , Humans , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Rats
5.
Atmospheric Chemistry and Physics ; 22(8):5495-5514, 2022.
Article in English | ProQuest Central | ID: covidwho-1811067

ABSTRACT

PM2.5, generated via both direct emission and secondary formation, can have varying environmental impacts due to different physical and chemical properties of its components. However, traditional methods to quantify different PM2.5 components are often based on online or offline observations and numerical models, which are generally high economic cost- or labor-intensive. In this study, we develop a new method, named Multi-Tracer Estimation Algorithm (MTEA), to identify the primary and secondary components from routine observation of PM2.5. By comparing with long-term and short-term measurements of aerosol chemical components in China and the United States, it is proven that MTEA can successfully capture the magnitude and variation of the primary PM2.5 (PPM) and secondary PM2.5 (SPM). Applying MTEA to the China National Air Quality Network, we find that (1) SPM accounted for 63.5 % of the PM2.5 in cities in southern China on average during 2014–2018, while the proportion dropped to 57.1 % in the north of China, and at the same time the secondary proportion in regional background regions was ∼ 19 % higher than that in populous regions;(2) the summertime secondary PM2.5 proportion presented a slight but consistent increasing trend (from 58.5 % to 59.2 %) in most populous cities, mainly because of the recent increase in O3 pollution in China;(3) the secondary PM2.5 proportion in Beijing significantly increased by 34 % during the COVID-19 lockdown, which might be the main reason for the observed unexpected PM pollution in this special period;and finally, (4) SPM and O3 showed similar positive correlations in the Beijing-Tianjin-Hebei (BTH) and Yangtze River Delta (YRD) regions, but the correlations between total PM2.5 and O3 in these two regions, as determined from PPM levels, were quite different. In general, MTEA is a promising tool for efficiently estimating PPM and SPM, and has huge potential for future PM mitigation.

6.
Biosens Bioelectron ; 208: 114234, 2022 Jul 15.
Article in English | MEDLINE | ID: covidwho-1767930

ABSTRACT

Chronic kidney disease (CKD) is the most neglected chronic disease affecting over 750 million persons in the world. Currently, many patients with cancers or other chronic diseases (i.e., CKD) struggle to receive clinical treatment or examination due to hospitals cancelling or delaying in the COVID-19 pandemic, which may increase the risk of death. Cystatin C (Cys C) has been proposed as a potential glomerular filtration rate (GFR) marker for the early detection of acute kidney injury and CKD. However, most traditional methods for Cys C detection are immunoassays using serum as a sample and are tedious to perform and economically burdensome. To diagnose the disease in the early stage and carry out daily management during the current pandemic, we developed an integration of hydrogel microneedle patch (HMNP) and lateral flow cassette (LFC) to rapidly detect Cys C in skin interstitial fluid (ISF) in 25 min for blood-free CKD management anytime and anywhere by the naked eye that can reduce the impact of an individual's quality of life and life expectancy. Conceivably, this strategy presents a wide scope in the application of numerous other diseases if corresponding analytes are available in skin ISF.


Subject(s)
Biosensing Techniques , COVID-19 , Renal Insufficiency, Chronic , COVID-19/diagnosis , Creatinine , Female , Humans , Male , Pandemics , Point-of-Care Testing , Quality of Life , Renal Insufficiency, Chronic/diagnosis
7.
Applied Sciences ; 12(3):1617, 2022.
Article in English | ProQuest Central | ID: covidwho-1731924

ABSTRACT

In Saudi Arabia, the country’s progress toward appropriate and inclusive education programs for children with disabilities is still evolving. A crucial aspect of this evolution has been the development of a comprehensive assessment battery that covers a broad range of cognitive factors for the diagnosis of neurodevelopment disorders and other types of intellectual atypicalities, including giftedness. The Alif–Ya Assessment Battery consists of 47 subtests based on various theories of intelligence. Alif–Ya capitalizes on advanced technologies to enable its delivery either in person or remotely. Moreover, over half of Alif–Ya’s subtests are adaptive;items are selected for the test takers based on their previous responses. In this paper, we provide an overview of the Alif–Ya Assessment Battery, describe how it was designed to make the best use of the latest and best features of technology for the appropriate and accurate assessment of children and adolescents in the Kingdom of Saudi Arabia via remote or in-person administration, and present initial data collected with the battery.

8.
Lancet Microbe ; 3(3): e193-e202, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1721237

ABSTRACT

BACKGROUND: Safe and effective vaccines are urgently needed to end the COVID-19 pandemic caused by SARS-CoV-2 infection. We aimed to assess the preliminary safety, tolerability, and immunogenicity of an mRNA vaccine ARCoV, which encodes the SARS-CoV-2 spike protein receptor-binding domain (RBD). METHODS: This single centre, double-blind, randomised, placebo-controlled, dose-escalation, phase 1 trial of ARCoV was conducted at Shulan (Hangzhou) hospital in Hangzhou, Zhejiang province, China. Healthy adults aged 18-59 years negative for SARS-CoV-2 infection were enrolled and randomly assigned using block randomisation to receive an intramuscular injection of vaccine or placebo. Vaccine doses were 5 µg, 10 µg, 15 µg, 20 µg, and 25 µg. The first six participants in each block were sentinels and along with the remaining 18 participants, were randomly assigned to groups (5:1). In block 1 sentinels were given the lowest vaccine dose and after a 4-day observation with confirmed safety analyses, the remaining 18 participants in the same dose group proceeded and sentinels in block 2 were given their first administration on a two-dose schedule, 28 days apart. All participants, investigators, and staff doing laboratory analyses were masked to treatment allocation. Humoral responses were assessed by measuring anti-SARS-CoV-2 RBD IgG using a standardised ELISA and neutralising antibodies using pseudovirus-based and live SARS-CoV-2 neutralisation assays. SARS-CoV-2 RBD-specific T-cell responses, including IFN-γ and IL-2 production, were assessed using an enzyme-linked immunospot (ELISpot) assay. The primary outcome for safety was incidence of adverse events or adverse reactions within 60 min, and at days 7, 14, and 28 after each vaccine dose. The secondary safety outcome was abnormal changes detected by laboratory tests at days 1, 4, 7, and 28 after each vaccine dose. For immunogenicity, the secondary outcome was humoral immune responses: titres of neutralising antibodies to live SARS-CoV-2, neutralising antibodies to pseudovirus, and RBD-specific IgG at baseline and 28 days after first vaccination and at days 7, 15, and 28 after second vaccination. The exploratory outcome was SARS-CoV-2-specific T-cell responses at 7 days after the first vaccination and at days 7 and 15 after the second vaccination. This trial is registered with www.chictr.org.cn (ChiCTR2000039212). FINDINGS: Between Oct 30 and Dec 2, 2020, 230 individuals were screened and 120 eligible participants were randomly assigned to receive five-dose levels of ARCoV or a placebo (20 per group). All participants received the first vaccination and 118 received the second dose. No serious adverse events were reported within 56 days after vaccination and the majority of adverse events were mild or moderate. Fever was the most common systemic adverse reaction (one [5%] of 20 in the 5 µg group, 13 [65%] of 20 in the 10 µg group, 17 [85%] of 20 in the 15 µg group, 19 [95%] of 20 in the 20 µg group, 16 [100%] of 16 in the 25 µg group; p<0·0001). The incidence of grade 3 systemic adverse events were none (0%) of 20 in the 5 µg group, three (15%) of 20 in the 10 µg group, six (30%) of 20 in the 15 µg group, seven (35%) of 20 in the 20 µg group, five (31%) of 16 in the 25 µg group, and none (0%) of 20 in the placebo group (p=0·0013). As expected, the majority of fever resolved in the first 2 days after vaccination for all groups. The incidence of solicited systemic adverse events was similar after administration of ARCoV as a first or second vaccination. Humoral immune responses including anti-RBD IgG and neutralising antibodies increased significantly 7 days after the second dose and peaked between 14 and 28 days thereafter. Specific T-cell response peaked between 7 and 14 days after full vaccination. 15 µg induced the highest titre of neutralising antibodies, which was about twofold more than the antibody titre of convalescent patients with COVID-19. INTERPRETATION: ARCoV was safe and well tolerated at all five doses. The acceptable safety profile, together with the induction of strong humoral and cellular immune responses, support further clinical testing of ARCoV at a large scale. FUNDING: National Key Research and Development Project of China, Academy of Medical Sciences China, National Natural Science Foundation China, and Chinese Academy of Medical Sciences.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , China , Humans , Immunogenicity, Vaccine , Immunoglobulin G , Pandemics/prevention & control , Spike Glycoprotein, Coronavirus , Vaccines, Synthetic
9.
SSRN; 2021.
Preprint in English | SSRN | ID: ppcovidwho-329306

ABSTRACT

This paper studies the impact of the COVID-19 on the stock ambiguity, risks, liquidity, and stock prices in China stock market, before and after the outbreak of COVID-19 in China during the Chinese New Year holidays in 2020. We measure stock ambiguity using the intraday trading data from the stock market. The outbreak of COVID-19 significantly impacts the average stock ambiguity, risk, and illiquidity in China and induces structure break in the market average ambiguity. However, the equity premium and liquidity premium change little during the same period. The market average stock ambiguity and risks decrease, and stock liquidity improves to pre-pandemic levels as the pandemic is under control in China. The market average stock ambiguity and risks in China increase when the confirmed new cases in the U.S. surge in the second half of 2020. We also find a significant “flight-to-liquidity” phenomenon, and the equally-weighted (value-weighted) 20-trading-day liquidity premium declined significantly to about -4.42% (-6.48%) during the fourth quarter of 2020.

10.
Atmosphere ; 13(2):174, 2022.
Article in English | ProQuest Central | ID: covidwho-1704199

ABSTRACT

In recent years, air pollution has received serious concerns from researchers, media, and the public sectors, but air pollution from agricultural production activities has not received enough attention. This paper focuses on agricultural air pollution in central China, which is aggravated by the ongoing rural labor migration trend. With a set of panel data released from Hubei and Hunan provinces in China, we adopt the mediating effect model to explore the relationship between rural labor migration and air pollution caused by agricultural activity in China. First, we use the inventory analysis method and principal component analysis method to calculate the comprehensive index of the air pollution of agriculture in 152 counties and districts from Hubei and Hunan provinces, and we empirically test the impact of labor migration on air pollution with a mediating effect model as well as carry out regional heterogeneity analysis on the pollution effect of these two provinces mentioned above. The analysis above indicates that the increase of labor migration has intensified the comprehensive index of air pollution caused by agricultural activity by changing the supply of labor force in the agricultural sector, the budget line of rural residents, and the scale of agricultural production and crop planting structure, but there is a difference in the indirect total effect between the two provinces mentioned above according to our regional heterogeneity analysis. This study is a necessary extension to studies on alleviating and controlling air pollution in China.

11.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-323671

ABSTRACT

Background: Existing literatures demonstrated that meteorological factors could be of importance in affecting the spread patterns of the respiratory infectious diseases. However, how ambient temperature may influence the transmissibility of COVID-19 remains unclear. Objectives: We explore the association between ambient temperature and transmissibility of COVID-19 in different regions across China. Methods: : The surveillance data on COVID-19 and meteorological factors were collected from 28 provincial level regions in China, and estimated the instantaneous reproductive number ( R t ). The generalized additive model was used to assess the relationship between mean temperature and R t . Results: : There were 12745 COVID-19 cases collected in the study areas. We report the effect of temperature on R t is not of statistical significance, which holds for most of included regions except for those in North China. Conclusions: We found little statistical evidence for that the higher temperature may reduce the transmissibility of COVID-19.

12.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-315267

ABSTRACT

Background: The current worldwide pandemic of Coronavirus Disease 2019 (COVID-19) has posed a serious threat to global public health, and the mortality rate of critical ill patients remains high. The purpose of this study was to identify factors that early predict the progression of COVID-19 from severe to critical illness. Methods: : This retrospective cohort study included adult patients with severe or critical ill COVID-19 who were consecutively admitted to the Zhongfaxincheng campus of Tongji Hospital (Wuhan, China) from February 8 to 18, 2020. Baseline variables, data at hospital admission and during hospital stay, as well as clinical outcomes were collected from electronic medical records system. The primary endpoint was the development of critical illness. A multivariable logistic regression model was used to identify independent factors that were associated with the progression from severe to critical illness. Results: : A total of 138 patients were included in the analysis;of them 119 were diagnosed as severe cases and 16 as critical ill cases at hospital admission. During hospital stay, 19 more severe cases progressed to critical illness. For all enrolled patients, longer duration from diagnosis to admission (odds ratio [OR] 1.108, 95% CI 1.022-1.202;P=0.013), pulse oxygen saturation at admission <93% (OR 5.775, 95% CI 1.257-26.535;P=0.024), higher neutrophil count (OR 1.495, 95% CI 1.177-1.899;P=0.001) and higher creatine kinase-MB level at admission (OR 2.449, 95% CI 1.089-5.511;P=0.030) were associated with a higher risk, whereas higher lymphocyte count at admission (OR 0.149, 95% CI 0.026-0.852;P=0.032) was associated with a lower risk of critical illness development. For the subgroup of severe cases at hospital admission, the above factors except creatine kinase-MB level were also found to have similar correlation with critical illness development. Conclusions: : Higher neutrophil count and lower lymphocyte count at admission were early independent predictors of progression to critical illness in severe COVID-19 patients.

13.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-312628

ABSTRACT

The identification of protein-ligand interaction plays a key role in biochemical research and drug discovery. Although deep learning has recently shown great promise in discovering new drugs, there remains a gap between deep learning-based and experimental approaches. Here we propose a novel framework, named AIMEE, integrating AI Model and Enzymology Experiments, to identify inhibitors against 3CL protease of SARS-CoV-2, which has taken a significant toll on people across the globe. From a bioactive chemical library, we have conducted two rounds of experiments and identified six novel inhibitors with a hit rate of 29.41%, and four of them showed an IC50 value less than 3 μM. Moreover, we explored the interpretability of the central model in AIMEE, mapping the deep learning extracted features to domain knowledge of chemical properties. Based on this knowledge, a commercially available compound was selected and proven to be an activity-based probe of 3CLpro. This work highlights the great potential of combining deep learning models and biochemical experiments for intelligent iteration and expanding the boundaries of drug discovery.

14.
Health Sci Rep ; 5(1): e496, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1651083

ABSTRACT

BACKGROUND AND AIMS: Before COVID-19 was declared a global pandemic, the U.S. Centers for Disease Control and Prevention (CDC), the National Institute of Allergy and Infectious Diseases (NIAID), and many other organizations published many images of its pathogen (namely SARS-CoV-2) to raise public awareness of the disease. Despite their scientific and aesthetic values, such images may convey metaphoric meanings and cause a subsequent impact on viewers' fear and disgust. This study investigated how exposure to the SARS-CoV-2 images might shape viewers' fear, disgust, and risk perception of COVID-19. METHODS: Seventy images depicting the SARS-CoV-2 were collected from the websites of CDC, NIAID, and third-party organizations in early 2020. We first showed the images to a group of 492 adults recruited from the Amazon Mechanical Turk (MTurk) and asked them to rate their levels of fear and disgust for each image. Results of this pre-test allowed us to identify images that evoked high, medium, and low levels of fear and disgust, which were then used as treatment stimuli for an online experiment with a national sample of 500 U.S. adults. RESULTS: Exposure to the selected SARS-CoV-2 images caused different levels of disgust, but not fear, among the members of the national sample. Noticeably, the images evoking the highest level of disgust backfired among those who were least concerned about COVID and caused less fear than images evoking the lowest level of disgust. Image exposure was not associated with risk perception of the disease. CONCLUSION: This study found that the seemingly objective visualizations of the SARS-CoV-2 are not emotionally neutral. Scientists, agencies, and media professionals should be mindful of the potential emotional impact of science visualizations, such as when creating the iconic image for COVID-19 or other infectious diseases.

15.
Front Neurol ; 12: 778618, 2021.
Article in English | MEDLINE | ID: covidwho-1555691

ABSTRACT

Objective: This study was conducted to investigate the hesitancy and response of people with epilepsy (PWE) to the coronavirus disease 2019 (COVID-19) vaccine. Methods: We conducted an online survey among PWE in northeast China about hesitancy and response to the COVID-19 vaccine. Their demographic background and symptomatic data about epilepsy were also recorded, and we analyzed the epilepsy-related risk factors in delaying the vaccine. Results: In total, 357 patients with confirmed epilepsy were included in the survey, and only 38 (11%) patients received the COVID-19 vaccine. Fear of aggravating epilepsy (58%, n = 185), discouragement from health workers for epilepsy (22%, n = 70), and fear of patients of other unknown serious side effects (13%, n = 42) were the main reasons for delaying vaccination. A higher seizure frequency was the only epilepsy-related risk factor in delaying the vaccine (OR = 1.104, 95% CI: 0.988-1.233). None of the vaccinated patients reported that the vaccine aggravated their epilepsy. Significance: Understanding concerns about the COVID-19 vaccine among PWE could help to improve health education and promote the establishment of an immune barrier.

16.
Microchem J ; 173: 107046, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1540859

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has dramatically changed the world, is a highly contagious virus. The timely and accurate diagnosis of SARS-CoV-2 infections is vital for disease control and prevention. Here in this work, a fluorescence immunoassay was developed to detect 2019 Novel Coronavirus antibodies (2019-nCoV mAb). Fluorescent graphene quantum dots (GQDs) and Ag@Au nanoparticles (Ag@AuNPs) were successfully synthesized and characterized. Fluorescence resonance energy transfer (FRET) enables effective quenching of GQDs fluorescence by Ag@AuNPs. With the presence of 2019-nCoV mAb, a steric hindrance was observed between the Ag@AuNPs-NCP (2019-nCoV antigen) complex and GQDs, which reduced the FRET efficiency and restored the fluorescence of GQDs. The fluorescence enhancement efficiency has a satisfactory linear relationship with the logarithm of the 2019-nCoV mAb in a concentration range of 0.1 pg mL-1-10 ng mL-1, and the limit of detection was 50 fg mL-1. The method has good selectivity. When the serum sample was spiked with 2019-nCoV mAb, the recovery rate was between 90.8% and 103.3%. The fluorescence immunosensor demonstrates the potential to complement the existing serological assays for COVID-19 diagnosis.

17.
Microsyst Nanoeng ; 7: 94, 2021.
Article in English | MEDLINE | ID: covidwho-1528008

ABSTRACT

Coronavirus disease 2019 (COVID-19) has emerged, rapidly spread and caused significant morbidity and mortality worldwide. There is an urgent public health need for rapid, sensitive, specific, and on-site diagnostic tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this study, a fully integrated and portable analyzer was developed to detect SARS-CoV-2 from swab samples based on solid-phase nucleic acid extraction and reverse transcription loop-mediated isothermal amplification (RT-LAMP). The swab can be directly inserted into a cassette for multiplexed detection of respiratory pathogens without pre-preparation. The overall detection process, including swab rinsing, magnetic bead-based nucleic acid extraction, and 8-plex real-time RT-LAMP, can be automatically performed in the cassette within 80 min. The functionality of the cassette was validated by detecting the presence of a SARS-CoV-2 pseudovirus and three other respiratory pathogens, i.e., Klebsiella pneumoniae, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. The limit of detection (LoD) for the SARS-CoV-2 pseudovirus was 2.5 copies/µL with both primer sets (N gene and ORF1ab gene), and the three bacterial species were successfully detected with an LoD of 2.5 colony-forming units (CFU)/µL in 800 µL of swab rinse. Thus, the analyzer developed in this study has the potential to rapidly detect SARS-CoV-2 and other respiratory pathogens on site in a "raw-sample-in and answer-out" manner.

18.
J Virol ; 95(24): e0153721, 2021 11 23.
Article in English | MEDLINE | ID: covidwho-1434898

ABSTRACT

Autophagy is thought to be involved in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, how SARS-CoV-2 interferes with the autophagic pathway and whether autophagy contributes to virus infection in vivo is unclear. In this study, we identified SARS-CoV-2-triggered autophagy in animal models, including the long-tailed or crab-eating macaque (Macaca fascicularis), human angiotensin-converting enzyme 2 (hACE2) transgenic mice, and xenografted human lung tissues. In Vero E6 and Huh-7 cells, SARS-CoV-2 induces autophagosome formation, accompanied by consistent autophagic events, including inhibition of the Akt-mTOR pathway and activation of the ULK-1-Atg13 and VPS34-VPS15-Beclin1 complexes, but it blocks autophagosome-lysosome fusion. Modulation of autophagic elements, including the VPS34 complex and Atg14, but not Atg5, inhibits SARS-CoV-2 replication. Moreover, this study represents the first to demonstrate that the mouse bearing xenografted human lung tissue is a suitable model for SARS-CoV-2 infection and that autophagy inhibition suppresses SARS-CoV-2 replication and ameliorates virus-associated pneumonia in human lung tissues. We also observed a critical role of autophagy in SARS-CoV-2 infection in an hACE2 transgenic mouse model. This study, therefore, gives insights into the mechanisms by which SARS-CoV-2 manipulates autophagosome formation, and we suggest that autophagy-inhibiting agents might be useful as therapeutic agents against SARS-CoV-2 infection. IMPORTANCE Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic with limited therapeutics. Insights into the virus-host interactions contribute substantially to the development of anti-SARS-CoV-2 therapeutics. The novelty of this study is the use of a new animal model: mice xenografted with human lung tissues. Using a combination of in vitro and in vivo studies, we have obtained experimental evidence that induction of autophagy contributes to SARS-CoV-2 infection and improves our understanding of potential therapeutic targets for SARS-CoV-2.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , Autophagy , COVID-19/drug therapy , COVID-19/virology , Lung/virology , SARS-CoV-2 , Virus Replication , Angiotensin-Converting Enzyme 2/metabolism , Animals , Autophagosomes , Cell Line, Tumor , Chlorocebus aethiops , Humans , Lung/pathology , Macaca , Male , Mice , Mice, Transgenic , Pneumonia, Viral/drug therapy , RNA, Small Interfering/metabolism , Vero Cells
19.
Front Psychiatry ; 12: 708698, 2021.
Article in English | MEDLINE | ID: covidwho-1405440

ABSTRACT

Background: Studies showed that healthcare workers (HCWs) and pregnant women bore the burden of mental problems during the coronavirus disease 2019 (COVID-19) pandemic. While, few studies have focused on the psychological impact of COVID-19 pandemic on pregnant women who work at healthcare settings. This study aimed to investigate and compare the prevalence difference of psychological symptoms between pregnant HCWs and pregnant non-HCWs during the early stage of COVID-19 pandemic in China. Methods: A cross-sectional online survey with anonymous structured questionnaires was conducted from February 15 to March 9, 2020. A total of 205 pregnant women in Chongqing, China were recruited. The mental health status was assessed using symptom checklist-90 (SCL-90). Results: Our sample was composed of 83 pregnant HCWs (mean age = 29.8) and 122 pregnant non-HCWs (mean age = 30.8). The results suggested the prevalence of psychological symptoms (the factor score ≥2) among all pregnant women ranged from 6.83% (psychosis symptoms) to 17.56% (obsessive-compulsive symptoms). Compared with pregnant non-HCWs, pregnant HCWs reported higher prevalence of psychological symptoms in 10 factors of SCL-90. After controlling the confounding variables, multiple logistic regression demonstrated that pregnant HCWs experienced higher prevalence of psychological symptoms of somatization (18.07 vs. 5.74%, p = 0.006, aOR = 4.52), anxiety disorders (16.87 vs. 6.56%, p = 0.016, aOR = 3.54), and hostility (24.10 vs. 10.66%, p = 0.027, aOR = 2.70) than those among pregnant non-HCW. Conclusion: Our study indicated that pregnant HCWs were more likely to suffer from mental health distress than pregnant non-HCWs during the early stage of COVID-19 pandemic. It is vital to implement targeted psychological interventions for pregnant women, especially for pregnant HCWs to cope with distress when facing the emerging infectious diseases.

20.
ACS Chem Biol ; 16(8): 1469-1481, 2021 08 20.
Article in English | MEDLINE | ID: covidwho-1387143

ABSTRACT

The programmed -1 ribosomal frameshifting element (PFSE) of SARS-CoV-2 is a well conserved structured RNA found in all coronaviruses' genomes. By adopting a pseudoknot structure in the presence of the ribosome, the PFSE promotes a ribosomal frameshifting event near the stop codon of the first open reading frame Orf1a during translation of the polyprotein pp1a. Frameshifting results in continuation of pp1a via a new open reading frame, Orf1b, that produces the longer pp1ab polyprotein. Polyproteins pp1a and pp1ab produce nonstructural proteins NSPs 1-10 and NSPs 1-16, respectively, which contribute vital functions during the viral life cycle and must be present in the proper stoichiometry. Both drugs and sequence alterations that affect the stability of the -1 programmed ribosomal frameshifting element disrupt the stoichiometry of the NSPs produced, which compromise viral replication. For this reason, the -1 programmed frameshifting element is considered a promising drug target. Using chaperone assisted RNA crystallography, we successfully crystallized and solved the three-dimensional structure of the PFSE. We observe a three-stem H-type pseudoknot structure with the three stems stacked in a vertical orientation stabilized by two triple base pairs at the stem 1/stem 2 and stem 1/stem 3 junctions. This structure provides a new conformation of PFSE distinct from the bent conformations inferred from midresolution cryo-EM models and provides a high-resolution framework for mechanistic investigations and structure-based drug design.


Subject(s)
Crystallography/methods , Frameshifting, Ribosomal/physiology , Molecular Chaperones , RNA, Viral/metabolism , SARS-CoV-2/metabolism , Humans , Models, Molecular , Nucleic Acid Conformation , RNA, Viral/genetics , Ribosomes/metabolism , SARS-CoV-2/genetics , Viral Proteins/chemistry , Viral Proteins/genetics , Viral Proteins/metabolism , Virus Replication/physiology
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