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1.
Chinese Journal of Microbiology and Immunology (China) ; 42(1):16-22, 2022.
Article in Chinese | EMBASE | ID: covidwho-1928714

ABSTRACT

Objective To detect the serum levels of SARS-CoV-2-specific IgM and IgG antibodies in patients infected with SARS-CoV-2 and recipients of inactivated vaccine in different periods for understanding their variation patterns in vivo. Methods Chemiluminescence immunoassay was used to detect the levels of SARS-CoV-2-specific IgM and IgG antibodies in 144 serum samples of 44 COVID-19 patients, 381 serum samples of 118 asymptomatic infected cases and 398 serum samples of 273 inactivated vaccine recipients collected at different periods. The results were statistically analyzed together with basic characteristics and vaccination status. Results The positive rates of IgM antibody in COVID-19 patients, asymptomatic infected cases and inactivated vaccine recipients were 52. 27% (23 / 44), 23. 73% (28 / 118) and 14. 29% (39 / 273). The positive rate of IgM antibody was higher in COVID-19 patients than in asymptomatic infected cases and vaccine recipients (χ2 = 12. 106, P = 0. 001;χ2 = 34. 755, P<0. 001). The positive rates of IgG antibody in the three populations were 100. 00% (44 / 44), 97. 46% (115 / 118) and 98. 81% (166 / 168), and the differences were not statistically significant (χ2 = 2. 944, P = 0. 229). In COVID-19 patients, the concentration of IgM antibody in <40 years old group was lower than that in ≥40 years old group (Waldχ2 = 6. 609, P = 0. 010), and the concentration of IgG antibody in patients with vaccination was higher than that in patients without vaccination (Waldχ2 = 12. 402,P<0. 001). In asymptomatic infected cases, the concentration of IgG antibody was higher in people with vaccination than in those without vaccination (Waldχ2 = 4. 530, P = 0. 033). In SARS-CoV-2 vaccine recipients, the concentration of IgG antibody in <40 years old group was higher than that in ≥40 years old group (Waldχ2 = 9. 565, P = 0. 002). Dynamic analysis of antibody levels showed that from week 1 to week 9, the concentrations of IgM and IgG antibodies in COVID-19 patients were higher than those in asymptomatic infected cases and vaccine recipients. Conclusions The concentrations of IgM and IgG antibodies in COVID-19 patients were higher than those in asymptomatic infected cases and inactivated vaccine recipients. COVID-19 patients aged ≥40 years had higher level of IgM antibody. COVID-19 patients and asymptomatic infected cases who had received vaccination had higher concentration of IgG antibody. Inactivated vaccine showed good immunogenicity after whole course of immunization, and the IgG antibody level in <40 years old group was higher.

2.
J Hosp Infect ; 127: 91-100, 2022 Jul 02.
Article in English | MEDLINE | ID: covidwho-1914598

ABSTRACT

BACKGROUND: Aerosol-borne diseases such as COVID-19 may outbreak occasionally in various regions of the world, inevitably resulting in short-term shortage and corresponding reuse of disposable respirators. AIM: To investigate the effective disinfection methods, reusable duration and frequency of N95 respirators. METHODS: Based on the self-built respirator simulation test system, and under combinations of experimental conditions of three N95 respirators × 0-200 nm NaCl aerosols × three simulated breathing flow rates (15, 50 and 85 L/min) × two disinfection methods (dry heating and ultraviolet (UV) radiation), this study continuously measured the changes in filtration efficiency of all respirators during multi-cycles of '8-h simulated donning + disinfection' until the penetration reached ≥5%. FINDINGS: Multi-cycles of dry heating and UV radiation treatments on the reused (i.e., multiple 8-h donning) N95 respirators had a minimal effect (<0.5%) on the respirator filtration efficiency, and even at 85 L/min, all tested N95 respirators were able to maintain filtration efficiencies ≥95% for at least 30 h or four reuse cycles of '8-h donning + disinfection', while a lower breathing flow rate (15 L/min) plus the exhalation valve could further extend the N95 respirator's usability duration up to 140 h or 18 reuse cycles of '8-h donning + disinfection'. As the respirator wearing time extended, aerosol penetration slowly increased in a quadratic function with a negative second-order coefficient, and the penetration increment during each cycle of 8-h donning was less than 0.9%. CONCLUSION: Multi-cycles of N95 respirator reuse in combination with dry heating or UV irradiation disinfection are feasible.

3.
Embase; 2022.
Preprint in English | EMBASE | ID: ppcovidwho-334805

ABSTRACT

Omicron sub-lineage BA.2 has rapidly surged globally, accounting for over 60% of recent SARS-CoV-2 infections. Newly acquired RBD mutations and high transmission advantage over BA.1 urge the investigation of BA.2's immune evasion capability. Here, we show that BA.2 causes strong neutralization resistance, comparable to BA.1, in vaccinated individuals' plasma. However, BA.2 displays more severe antibody evasion in BA.1 convalescents, and most prominently, in vaccinated SARS convalescents' plasma, suggesting a substantial antigenicity difference between BA.2 and BA.1. To specify, we determined the escaping mutation profiles1,2 of 714 SARS-CoV-2 RBD neutralizing antibodies, including 241 broad sarbecovirus neutralizing antibodies isolated from SARS convalescents, and measured their neutralization efficacy against BA.1, BA.1.1, BA.2. Importantly, BA.2 specifically induces large-scale escape of BA.1/BA.1.1effective broad sarbecovirus neutralizing antibodies via novel mutations T376A, D405N, and R408S. These sites were highly conserved across sarbecoviruses, suggesting that Omicron BA.2 arose from immune pressure selection instead of zoonotic spillover. Moreover, BA.2 reduces the efficacy of S309 (Sotrovimab)3,4 and broad sarbecovirus neutralizing antibodies targeting the similar epitope region, including BD55-5840. Structural comparisons of BD55-5840 in complexes with BA.1 and BA.2 spike suggest that BA.2 could hinder antibody binding through S371F-induced N343-glycan displacement. Intriguingly, the absence of G446S mutation in BA.2 enabled a proportion of 440-449 linear epitope targeting antibodies to retain neutralizing efficacy, including COV2-2130 (Cilgavimab)5. Together, we showed that BA.2 exhibits distinct antigenicity compared to BA.1 and provided a comprehensive profile of SARS-CoV-2 antibody escaping mutations. Our study offers critical insights into the humoral immune evading mechanism of current and future variants.

4.
2021 China Automation Congress, CAC 2021 ; : 4263-4268, 2021.
Article in English | Scopus | ID: covidwho-1806890

ABSTRACT

As a high-density crowd collection and dispersal carrier,rail transit is characterized by airtight confinement, which will provide an suitable environment for the potential spread of coronavirus disease. The virus distribution inside stations needs to be analyzed in order to adopt effective passenger flow organization strategies to reduce the risk of virus infection inside stations. With the help of aerodynamic principle, according to the virus transmission theory, the BIM simulation technology has been used to simulate the air flow direction of a certain station of Wuhan metro using Fluent software to qualitatively analyze the station's virus-prone gathering area and provide reference for station daily disinfection.The daily passenger flow organization of the station has been simulated considering the social force model.Comparing the overlap between the concentrated area of passenger flow density and the virus-prone area,a targeted imrovement plan of passenger flow organization has been proposed. The improvement measures have been verified quantitatively by two evaluation indexes: the average dwell time and virus susceptibility in pedestrian stations. The results show the effectiveness in reducing the probability of virus infection of passengers traveling in the station by disabling the station vending machines, reducing the number of passengers in the station, increasing the escalator rate, and optimizing the flow lines of passengers entering and exiting the station. The simulation results can provide inspiration and reference for normalized epidemic prevention in the daily operation of rail transit. © 2021 IEEE

5.
Embase;
Preprint in English | EMBASE | ID: ppcovidwho-326814

ABSTRACT

The outbreak of SARS-CoV-2 continues to pose a serious threat to human health and social and economic stability. In this study, we established an anti-coronavirus drug screening platform based on the Homogeneous Time Resolved Fluorescence (HTRF) technology and the interaction between the coronavirus S protein and its host receptor ACE2. This platform is a rapid, sensitive, specific, and high throughput system. With this platform, we screened two compound libraries of 2,864 molecules and identified three potential anti-coronavirus compounds: tannic acid (TA), TS-1276 (anthraquinone), and TS-984 (9-Methoxycanthin-6-one). Our in vitro validation experiments indicated that TS-984 strongly inhibits the interaction of the coronavirus S-protein and the human cell ACE2 receptor. This data suggests that TS-984 is a potent blocker of the interaction between the S-protein and ACE2, which might have the potential to be developed into an effective anti-coronavirus drug.

6.
2021 International Conference on E-Commerce and E-Management, ICECEM 2021 ; : 74-77, 2021.
Article in English | Scopus | ID: covidwho-1685072

ABSTRACT

The outbreak of COVID-19 has disrupted people's pace of life and greatly affected the normal development of industry and commerce. Different types of enterprises have experienced different degrees of losses. The e-commerce companies, which rely on both labor and information techniques, have been influenced obviously. To investigate the resilience supply chains of e-commerce companies in the post-epidemic era, we choose Jingdong (JD) as an example and identify their performances during this specific period. According to our analysis, JD has shown its strong supply chain management and service ability in the post-epidemic period of resuming work and production. Moreover, the functions of the digital technology integration system of the JD Smart Purchasing Platform are also demonstrated. It provides integrated supply chain service and procurement project service that faces those relative enterprises. In conclusion, applying the Information Visualization management system could provide an efficient reference for supply chain management of e-commerce companies. © 2021 IEEE.

7.
Internet Research ; 2022.
Article in English | Scopus | ID: covidwho-1612763

ABSTRACT

Purpose: Health-related online fake news (HOFN) has become a major social problem. HOFN can lead to the spread of ineffective and even harmful remedies. The study aims to understand Internet users' responses to HOFN during the coronavirus (COVID-19) pandemic using the protective action decision model (PADM). Design/methodology/approach: The authors collected pandemic severity data (regional number of confirmed cases) from government websites of the USA and China (Studies 1 and 2), search behavior from Google and Baidu search engines (Studies 1 and 2) and data regarding trust in two online fake news stories from two national surveys (Studies 2 and 3). All data were analyzed using a multi-level linear model. Findings: The research detected negative time-lagged relationships between pandemic severity and regional HOFN search behavior by three actual fake news stories from the USA and China (Study 1). Importantly, trust in HOFN served as a mediator in the time-lagged relationship between pandemic severity and search behavior (Study 2). Additionally, the relationship between pandemic severity and trust in HOFN varied according to individuals' perceived control (Study 3). Originality/value: The authors' results underscore the important role of PADM in understanding Internet users' trust in and search for HOFN. When people trust HOFN, they may seek more information to implement further protective actions. Importantly, it appears that trust in HOFN varies with environmental cues (regional pandemic severity) and with individuals' perceived control, providing insight into developing coping strategies during a pandemic. © 2021, Emerald Publishing Limited.

8.
Foreign Literature Studies ; 43(5):1-17, 2021.
Article in English | Scopus | ID: covidwho-1507573

ABSTRACT

Daniel R. Schwarz, Frederic J. Whiton Professor of English Literature at Cornell University, has been regarded as a master teacher, an influential literary critic, and a leading public intellectual. His prolific publications cover a wide variety of subjects, from Joseph Conrad, James Joyce, and Wallace Stevens to critical theory, the Holocaust, reading and teaching of literature, and New York City culture. Also, he has blogged regularly on the media and higher education for Huffington Post, and lectured all over the world, including teaching as a guest scholar at Peking University in 1993. On Behalf of Foreign Literature Studies, Zheng Li interviewed Schwarz on a series of issues, such as his humanistic and pluralistic critical approach, his philosophy of reading, the connection between modern art and modern literature, Holocaust Studies, and Jewish Studies. Schwarz sees reading as a kind of travel in which we explore how others live and think in both our own and different cultures. He believes that nothing makes clearer than the worldwide pandemic, Covid-19, that we are all united in "a community of common destiny", interdependent on one another. Finally, he expresses his gratefulness for the opportunities his life as teacher and scholar has presented and, with the lines from one of his favorite poems, C. P. Cavafy's "Ithaka", offers us a piece of advice, "Don't hurry the journey at all." © Copyright by Foreign Literature Studies. All right reserved.

9.
Chest ; 160(4):A2140, 2021.
Article in English | EMBASE | ID: covidwho-1466196

ABSTRACT

TOPIC: Pulmonary Manifestations of Systemic Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Babesiosis is a tick-borne illness caused by B. microti and other species and transmitted by the Ixodes tick. Acute respiratory distress syndrome (ARDS) can be a manifestation of babesiosis. CASE PRESENTATION: A 69 year old female with the past medical history of HTN, HLD and hypothyroidism who presented to hospital for 1 week of intermittent fever and generalized body aches. Patient denied any tick bites. She started to have intermittent fever around 40°C, nonproductive cough and generalized body aches, associated with night sweats, nausea, diarrhea. She took 1000mg Tylenol every 4 hours for fever and body aches for 1 week without improvement.Upon admission laboratory values were significant for hemolytic anemia (Hgb 9.4 g/dL, reticulocyte count 1.2%, LDH 4896 U/L, haptoglobin < 8mg/dL, total bilirubin 2.3 mg/dL), thrombocytopenia (platelet 38× 103/mm3) and leukopenia (WBC 2.7× 103/mm3), significantly elevated acetaminophen level (22.6), transaminitis (ALT 365 IU/L, AST 579 IU/L) and elevated INR (1.4). Blood parasite smear was positive for blood parasites (Malaria/Babesia: 9.6% RBC infected). Babesia Microti DNA RT-PCR was positive, Babesia Microti Ab (IgM) ≥ 1:320, Babesia Microti Ab (IgG) was 1:512, E. Chaffeensis Ab Ig G <1:64, E. Chaffeensis Ab Ig M <1:20, Lyme Ab Scr-Q <0.90. HIV and blood culture was negative. SARS-CoV-2 RNA was negative.Patient was admitted and received Acetylcysteine for acetaminophen toxicity, atovaquone, azithromycin, doxycycline for Babesia and borreliosis coverage. On day 2 of admission, acetaminophen level decreased to less than 10, transaminitis slowly improved. But patient developed shortness of breath, cough and hypoxia. Concerning severe babesiosis induced ARDS, chest CT angiogram was ordered and showed no evidence of pulmonary embolism but mild pulmonary interstitial edema. 2D Echo showed normal left ventricular systolic function and mild diastolic dysfunction. Patient received IV Lasix, symptoms improved and the CXR on day 6 showed pulmonary edema resolved.In the following days, patient continued to receive treatment for babesiosis, blood parasitemia cleared but Hgb decreased to 6.7 g/dL, patient received transfusion and Hgb level remained 7.9 g/dL on the day of discharge. 5 days after discharge, patient's Hgb level increased to 9 g/dL. 1 month after discharge, Hgb level increased to 12g/dL and transaminase level returned to normal. DISCUSSION: ARDS is a life-threatening condition characterized by severe hypoxemia due to pulmonary gas exchange failure. Though uncommon, tick-borne diseases could present with ARDS. Moreover, acetaminophen toxicity has also been linked to acute lung injury, making the correct diagnosis challenging. Early recognition and intervention led to a favorable outcome. CONCLUSIONS: ARDS can be an early onset manifestation after initiation of treatment for babesiosis and usually resolves with supportive treatment. REFERENCE #1: Autoimmune hemolytic anemia associated with babesiosis.Roshni Narurkar, Aleksandra Mamorska-Dyga, John C. Nelson and Delong Liu.Biomarker Research (2017) 5:14. REFERENCE #2: Yousef Nassar, Seth Richter. Babesiosis Presenting as Acute Liver Failure. Case Rep Gastroenterol 2017;11:769–773. REFERENCE #3: Boustani MR, Lepore TJ, Gelfand JA, Lazarus DS. Acute respiratory failure in patients treated for babesiosis. Am J Respir Crit Care Med. 1994 Jun;149(6):1689-91. doi: 10.1164/ajrccm.149.6.8004331.PMID: 8004331 Review. DISCLOSURES: No relevant relationships by Heather Bernstein, source=Web Response No relevant relationships by ALKA FARMER, source=Web Response No relevant relationships by CUIPING LI, source=Web Response No relevant relationships by Vinay Nakhate, source=Admin input No relevant relationships by kiritkumar parmar, source=Web Response No relevant relationships by Lin Zheng, source=Web Response

10.
IEEE Access ; 2021.
Article in English | Scopus | ID: covidwho-1393640

ABSTRACT

COVID-19 has spread rapidly across the world, leading to the insufficiency of medical resources in many regions. Early detection and identification of high-risk COVID-19 patients will contribute to early intervention and optimize medical resource allocation. Using the clinical data from the Affiliated Yueqing Hospital of Wenzhou Medical University (Yueqing, China), an evolutionary support vector machine model is designed to recognize and discriminate the severity of the COVID-19 by patients basic information and hematological indexes. The support vector machine is a frequently used pattern classification tool affected by both the kernel parameter setting and feature selection for its classification accuracy. This study recommends an enhanced Slime Mould Algorithm (ESMA), mixing a new movement strategy of white holes, black holes, and wormholes, to perform parameter optimization and feature selection simultaneously for SVM. Therefore, the proposed SVM framework (ESMA-SVM) can also obtain high-quality classification results, and it is less prone to stagnation in the classification process. To verify the capabilities of the proposed methodology, first, the performance of the ESMA is thoroughly verified by using IEEE CEC2017 benchmark functions and the diversity and compared with other similar methods experimentally using these standard benchmark functions. Moreover, the balance between diversification and intensification capability of the enhanced ESMA and the original SMA is also investigated statistically. Finally, the designed model ESMA-SVM and other competitive SVM models based on other optimization algorithms are applied to early recognition and discrimination of COVID-19 severity. Through the analysis of experimental results, the core compensations of ESMA are confirmed, and the ESMA-SVM can obtain strong performance in terms of several performance evaluation indexes on discrimination of COVID-19 severity. Author

11.
Ieee Transactions on Computational Social Systems ; 8(4):1042-1051, 2021.
Article in English | Web of Science | ID: covidwho-1349917

ABSTRACT

During the novel coronavirus pneumonia, the underlying comments and news of the epidemic had bombed on the Internet media and social networks, reflecting the views and attitudes of the governments, society, and individuals to the epidemic situation. Those comments are closely related to people's lives and blend with each other. Novel coronavirus pneumonia affects people's lives, and they publish comments on social networks and media, and the underlying information from social networks and Internet media in turn affects people's attitude to the epidemic and the measures, and strategies taken to fight coronavirus in life. We collect the comments from various social network platforms and network media such as Weibo, WeChat, Chinanews, Sina News, NetEase News, Sohu News, and analyze the overall situation of public opinion on the novel coronavirus pneumonia. We explore the interaction between online public opinion and real life using a variety of algorithms in different stages of the epidemic. We can obtain public attention and key nodes in the dissemination of public opinion by detecting hot events and calculating user's influence. The analysis of information dissemination path is conducive to the rapid propagation of healthy comments, curbing the spread of bad information. Event-specific details and topics are mined from large amounts of comments by thematic clustering and association relationship detecting, which helps to provide technical support for government response measures. The emotional analysis of Internet users' groups helps to guide the direction of public opinion. The situation analysis shows the deep blending and mutual influence between the online public opinion and the real world.

12.
Chinese Journal of Clinical Pharmacology and Therapeutics ; 26(2):213-216, 2021.
Article in Chinese | EMBASE | ID: covidwho-1146831

ABSTRACT

Since the outbreak of Coronavirus Disease 2019 (COVID-19), a large number of clinical trials affected by the epidemic are suspended and postponed, and clinical trial institutions have initiated a series of emergency management measures. The characteristics of the diagnosis and treatment of stomatology are that the doctors and patients are closed to each other face to face, it is easy to produce droplets and aerosols, and there are many invasive operations, which leads to high risk of cross infection. The epidemic of COVID-19 poses a huge challenge to the operation of stomatological clinical trials. This paper based on the epidemic prevention and control requirements and the consensus on clinical trial management under major public health emergencies, combined with the relevant work guidelines of the institution and the relevant clinical trial regulations, puts forward suggestions on the clinical trial operation management and protective measures during the epidemic period. It may be helpful to the stomatological clinical trial researchers and subjects during the period of COVID-19.

13.
Clin Radiol ; 76(5): 391.e33-391.e41, 2021 05.
Article in English | MEDLINE | ID: covidwho-1131209

ABSTRACT

AIM: To evaluate the lung function of coronavirus disease 2019 (COVID-19) patients using oxygen-enhanced (OE) ultrashort echo time (UTE) MRI. MATERIALS AND METHODS: Forty-nine patients with COVID-19 were included in the study. The OE-MRI was based on a respiratory-gated three-dimensional (3D) radial UTE sequence. For each patient, the percent signal enhancement (PSE) map was calculated using the expression PSE = (S100% - S21%)/S21%, where S21% and S100% are signals acquired during room air and 100% oxygen inhalation, respectively. Agreement of lesion detectability between UTE-MRI and computed tomography (CT) was performed using the kappa test. The Mann-Whitney U-test was used to evaluate the difference in the mean PSE between mild-type COVID-19 and common-type COVID-19. Spearman's test was used to assess the relationship between lesion mean PSE and lesion size. Furthermore, the Mann-Whitney U-test was used to evaluate the difference in region of interest (ROI) mean PSE between normal pulmonary parenchyma and lesions. The Kruskal-Wallis test was applied to test the difference in the mean PSE between different lesion types. RESULTS: CT and UTE-MRI reached good agreement in lesion detectability. Ventilation measures in mild-type patients (5.3 ± 5.5%) were significantly different from those in common-type patients (3 ± 3.9%). Besides, there was no significant correlation between lesion mean PSE and lesion size. The mean PSE of COVID-19 lesions (3.2 ± 4.9%) was significantly lower than that of the pulmonary parenchyma (5.4 ± 3.9%). No significant difference was found among different lesion types. CONCLUSION: OE-UTE-MRI could serve as a promising method for the assessment of lung function or treatment management of COVID-19 patients.


Subject(s)
COVID-19/diagnostic imaging , COVID-19/physiopathology , Lung/diagnostic imaging , Magnetic Resonance Imaging/methods , Pulmonary Ventilation , Adolescent , Adult , Aged , Feasibility Studies , Female , Humans , Imaging, Three-Dimensional , Lung/physiopathology , Male , Middle Aged , Oxygen , Prospective Studies , SARS-CoV-2 , Severity of Illness Index , Tomography, X-Ray Computed , Young Adult
14.
Dili Xuebao/Acta Geographica Sinica ; 75(11):2490-2504, 2020.
Article in Chinese | Scopus | ID: covidwho-1000622

ABSTRACT

The COVID-19 epidemic is a global public health crisis. It is of practical significance to objectively understand the public's responses and regional differences in order to improve policy control and scientific governance during major public health threats. In this study, a topic extraction and classification model was constructed based on the Latent Dirichlet Allocation topic model and the Random Forest algorithm. Thirteen topics were identified about public opinion in the Chinese SINA microblog from January 9 to March 10, 2020. The regional distribution characteristics were explored in terms of the amount, space, time sequence, and content in major urban agglomerations including Hubei Province, Beijing-Tianjin-Hebei urban agglomeration, Yangtze River Delta, Pearl River Delta, Chengdu-Chongqing region, and some border ports of China. The results showed that the spatio-temporal distribution of public opinion is related to the severity of the epidemic, degree of population aggregation, and level of economic development. The response of Chinese people is rational and positive, and the spatial distribution within these regions is obviously different. Among the regional hotspots, Beijing-Tianjin-Hebei region is centred on Beijing;the Yangtze River Delta is centred on Shanghai, followed by Nanjing, Hangzhou and other hotspots;the Pearl River Delta is centred on Guangzhou and Shenzhen;and Hubei Province is centred on Wuhan. The time series of topics in each region are synchronously related, but there are differences in timing sequence and periodic fluctuation in response time and intensity. The imbalance of resource allocation caused by the sharp rise of relief information in the short term is prominent, and the differences in response policies of various urban agglomerations combined with regional characteristics are not obvious. We should continue to focus on public opinion on epidemic situations in key areas and accurately respond to local regions according to its actual conditions. © 2020, Science Press. All right reserved.

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