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1.
Advanced Materials Interfaces ; 2022.
Article in English | Web of Science | ID: covidwho-2084974

ABSTRACT

Polymeric substrates can be endowed with antiviral properties by grafting N-chloramine precursors to the surface. These surfaces bind oxidative chlorine from a dilute chlorine bleach solution and are similarly recharged after depletion for reuse. Previously, enhanced antibacterial efficacy of quaternized N-chloramines compared to their neutral counterparts is reported. In this study, a new quaternized N-chloramine N-1-(3-methacrylamidopropyl)-N-1,N-1,N-10,N-10-tetramethyl-N-10-(2,2,6,6-tetramethylpiperidin-4-yl)decane-1,10-diaminium (MAMPIP) featuring two quaternary ammonium groups within the structure to boost the chlorination efficiency and achieve excellent antiviral efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is reported. Antiviral fabrics are prepared by free-radical graft polymerization of MAMPIP, or copolymerization of MAMPIP with a comonomer (acrylamide or methacrylamide) onto cotton fabrics to achieve enhanced durability to re-chlorination. The poly(MAMPIP) grafted cotton, after chlorination, is highly effective against SARS-CoV-2 and achieves 4.59 log reduction (99.997%) after 5 min contact. Samples grafted with the copolymer of MAMPIP and acrylamide or methacrylamide are resistant to hydrolysis during re-chlorination and retain high active chlorine and antiviral activity after 5 cycles of re-chlorination (>3 log reduction after 10 min contact). Furthermore, the N-chloramine coatings show excellent stability after exposure to simulated daylight conditions under an accelerated weathering tester, and storage for 200 days at 21 degrees C, 65% RH. The resulting quaternized N-chloramine grafted cotton is a suitable platform for reusable antiviral textiles.

2.
Front Hum Neurosci ; 16: 917851, 2022.
Article in English | MEDLINE | ID: covidwho-2009889

ABSTRACT

Infant and young child electrophysiology studies have provided information regarding the maturation of face-encoding neural processes. A limitation of previous research is that very few studies have examined face-encoding processes in children 12-48 months of age, a developmental period characterized by rapid changes in the ability to encode facial information. The present study sought to fill this gap in the literature via a longitudinal study examining the maturation of a primary node in the face-encoding network-the left and right fusiform gyrus (FFG). Whole-brain magnetoencephalography (MEG) data were obtained from 25 infants with typical development at 4-12 months, and with follow-up MEG exams every ∼12 months until 3-4 years old. Children were presented with color images of Face stimuli and visual noise images (matched on spatial frequency, color distribution, and outer contour) that served as Non-Face stimuli. Using distributed source modeling, left and right face-sensitive FFG evoked waveforms were obtained from each child at each visit, with face-sensitive activity identified via examining the difference between the Non-Face and Face FFG timecourses. Before 24 months of age (Visits 1 and 2) the face-sensitive FFG M290 response was the dominant response, observed in the left and right FFG ∼250-450 ms post-stimulus. By 3-4 years old (Visit 4), the left and right face-sensitive FFG response occurred at a latency consistent with a face-sensitive M170 response ∼100-250 ms post-stimulus. Face-sensitive left and right FFG peak latencies decreased as a function of age (with age explaining greater than 70% of the variance in face-sensitive FFG latency), and with an adult-like FFG latency observed at 3-4 years old. Study findings thus showed face-sensitive FFG maturational changes across the first 4 years of life. Whereas a face-sensitive M290 response was observed under 2 years of age, by 3-4 years old, an adult-like face-sensitive M170 response was observed bilaterally. Future studies evaluating the maturation of face-sensitive FFG activity in infants at risk for neurodevelopmental disorders are of interest, with the present findings suggesting age-specific face-sensitive neural markers of a priori interest.

3.
Research (Wash D C) ; 2022: 9864089, 2022.
Article in English | MEDLINE | ID: covidwho-1979971

ABSTRACT

Due to the rapid spread of coronavirus disease 2019 (COVID-19), there is an urgent requirement for the development of additional diagnostic tools for further analysis of the disease. The isolated nanobody Nb11-59 binds to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain (RBD) with high affinity to neutralize the virus and block the angiotensin-converting enzyme 2- (ACE2-) RBD interaction. Here, we introduce a novel nanobody-based radiotracer named 68Ga-Nb1159. The radiotracer retained high affinity for the RBD and showed reliable radiochemical characteristics both in vitro and in vivo. Preclinical positron emission tomography (PET) studies of 68Ga-Nb1159 in mice revealed its rapid clearance from circulation and robust uptake into the renal and urinary systems. Fortunately, 68Ga-Nb1159 could specifically reveal the distribution of the RBD in mice. This study also helped to evaluate the pharmacodynamic effects of the neutralizing nanobody. Moreover, 68Ga-Nb1159 may be a promising tool to explore the distribution of the RBD and improve the understanding of the virus. In particular, this study identified a novel molecular radioagent and established a reliable evaluation method for specifically investigating the RBD through noninvasive and visual PET technology.

4.
J Med Chem ; 65(16): 11058-11065, 2022 08 25.
Article in English | MEDLINE | ID: covidwho-1972507

ABSTRACT

Tuberculosis is caused by the bacterium Mycobacterium tuberculosis (Mtb) and is ranked as the second killer infectious disease after COVID-19. Proteasome accessory factor A (PafA) is considered an attractive target because of its low sequence conservation in humans and its role in virulence. In this study, we designed a mutant of Mtb PafA that enabled large-scale purification of active PafA. Using a devised high-throughput screening assay, two PafA inhibitors were discovered. ST1926 inhibited Mtb PafA by binding in the Pup binding groove, but it was less active against Corynebacterium glutamicum PafA because the ST1926-binding residues are not conserved. Bithionol bound to the conserved ATP-binding pocket, thereby, inhibits PafA in an ATP-competitive manner. Both ST1926 and bithionol inhibited the growth of an attenuated Mtb strain (H37Ra) at micromolar concentrations. Our work thus provides new tools for tuberculosis research and a foundation for future PafA-targeted drug development for treating tuberculosis.


Subject(s)
Mycobacterium tuberculosis , Proteasome Inhibitors , Adenosine Triphosphate/metabolism , Bacterial Proteins/metabolism , Bithionol/metabolism , Mycobacterium tuberculosis/drug effects , Proteasome Endopeptidase Complex/metabolism , Proteasome Inhibitors/chemistry , Proteasome Inhibitors/pharmacology
5.
Environ Sci Technol ; 56(14): 9988-9998, 2022 07 19.
Article in English | MEDLINE | ID: covidwho-1967575

ABSTRACT

Nitrogen dioxide (NO2) at the ground level poses a serious threat to environmental quality and public health. This study developed a novel, artificial intelligence approach by integrating spatiotemporally weighted information into the missing extra-trees and deep forest models to first fill the satellite data gaps and increase data availability by 49% and then derive daily 1 km surface NO2 concentrations over mainland China with full spatial coverage (100%) for the period 2019-2020 by combining surface NO2 measurements, satellite tropospheric NO2 columns derived from TROPOMI and OMI, atmospheric reanalysis, and model simulations. Our daily surface NO2 estimates have an average out-of-sample (out-of-city) cross-validation coefficient of determination of 0.93 (0.71) and root-mean-square error of 4.89 (9.95) µg/m3. The daily seamless high-resolution and high-quality dataset "ChinaHighNO2" allows us to examine spatial patterns at fine scales such as the urban-rural contrast. We observed systematic large differences between urban and rural areas (28% on average) in surface NO2, especially in provincial capitals. Strong holiday effects were found, with average declines of 22 and 14% during the Spring Festival and the National Day in China, respectively. Unlike North America and Europe, there is little difference between weekdays and weekends (within ±1 µg/m3). During the COVID-19 pandemic, surface NO2 concentrations decreased considerably and then gradually returned to normal levels around the 72nd day after the Lunar New Year in China, which is about 3 weeks longer than the tropospheric NO2 column, implying that the former can better represent the changes in NOx emissions.


Subject(s)
Air Pollutants , Air Pollution , COVID-19 , Air Pollutants/analysis , Air Pollution/analysis , Artificial Intelligence , China , Environmental Monitoring , Humans , Nitrogen Dioxide/analysis , Pandemics
6.
Front Psychol ; 13: 941535, 2022.
Article in English | MEDLINE | ID: covidwho-1933852

ABSTRACT

The study aims to build a model that predicts the behavior of the use of blended learning by English teachers of basic education in China in the environment of repeated lockdowns during the COVID-19 pandemic. It examines the relationships between ICT self-efficacy, organizational support for blended learning, attitudes toward blended learning, and the use of blended learning. Data were collected from 562 teachers using a survey questionnaire. Employing partial least squares structural equation modeling (PLS-SEM), a hypothesized model was tested for path coefficients and predictive power. This study found that ICT self-efficacy and organizational support for blended learning are sound predictors of teachers' use of blended learning and that the former appeared to be a stronger determinant. In addition, attitudes toward blended learning can directly influence teachers' use of blended learning and mediate the relationship between ICT efficacy and the use of blended learning and between organizational support for blended learning and the use of blended learning. These three variables account for 54.7% of the variance in teachers' use of blended learning.

8.
Leadership & Organization Development Journal ; 43(5):734-749, 2022.
Article in English | ProQuest Central | ID: covidwho-1901418

ABSTRACT

Purpose>Drawing upon conservation of resources theory, this study aims to explore how ethical leadership relates to subordinates' emotional exhaustion through the chain mediating effects of organizational networking behavior and organizational embeddedness.Design/methodology/approach>Data were collected from 447 airport employees in China. PROCESS macro in SPSS was used to test the hypotheses.Findings>Results indicated that ethical leadership is negatively correlated with emotional exhaustion;organizational networking behavior and organizational embeddedness play a chain mediating role in the negative relationship between ethical leadership and emotional exhaustion.Originality/value>This study provides new insights into the association between ethical leadership and emotional exhaustion, and enriches the antecedents and consequences of organizational networking behavior.

9.
Journal of Cleaner Production ; 348:N.PAG-N.PAG, 2022.
Article in English | Academic Search Complete | ID: covidwho-1783464

ABSTRACT

Managing ecosystems is considered a "wicked problem" without clear solutions due to the limited understanding of complex ecosystems and social dynamics. In this study, a method based on the Driving forces–Pressures–State–Impacts–Responses (DPSIR) framework was developed to reveal the Ecological Civilization Construction (ECC) together with structural equation modeling (SEM), panel data model (PDM), coupling and coordination degree (CCD) model, and data envelopment analysis (DEA). The SEM reveals that component Responses as exogenous variables can better explain the DPSIR framework nexuses than Driving forces, indicating that environmental protection measures taken by Chinese government played a dominant role in ECC. ECC indexes (ECCI) of 30 Chinese provinces were 18–87% higher in 2019 than 2012, and the PDM demonstrates that temperature, precipitation, and GDP can explain about 87.2% of ECCI variation among 30 provinces. About 12–40% increase in CCD within the DPSIR framework were detected in 30 Chinese provinces in 2019 compared to 2012. The DEA suggests that China's ECC's average comprehensive and technical efficiencies were only 0.62 and 0.77 in 2019, respectively. Meanwhile, these results show that ECC remains to be strengthened and coordinated. Implications on ECC were proposed for some provinces. Overall, this study proposes a Response-driven pathway named RDPSI can explain the achievements and limitation factors in China's ECC. Also, our results emphasize the importance of integrating science and technology, policy formulation, and precise implementation to achieve sustainable development. • A new method for studying the dynamic relationship of the SES is developed. • A sustainable development pathway named RDPSI is proposed. • China has formed a SES of positive feedback cycle, but the system is unstable. • There are increasingly significant spatial correlation issues in 30 Chinese provinces. [ FROM AUTHOR] Copyright of Journal of Cleaner Production is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

10.
Acta Pharmacol Sin ; 43(7): 1749-1757, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1671539

ABSTRACT

The spike protein of SARS-CoV-2 interacts with angiotensin-converting enzyme 2 (ACE2) of human respiratory epithelial cells, which leads to infection. Furthermore, low-dose radiation has been found to reduce inflammation and aid the curing of COVID-19. The receptor binding domain (RBD), a recombinant spike protein with a His tag at the C-terminus, binds to ACE2 in human body. We thus constructed a radioiodinated RBD as a molecule-targeted probe to non-invasively explore ACE2 expression in vivo, and to investigate radiotherapy pathway for inhibiting ACE2. RBD was labeled with [124I]NaI using an N-bromosuccinimide (NBS)-mediated method, and 124I-RBD was obtained after purification with a specific activity of 28.9 GBq/nmol. Its radiochemical purity was (RCP) over 90% in saline for 5 days. The dissociation constant of 124I-RBD binding to hACE2 was 75.7 nM. The uptake of 124I-RBD by HeLaACE+ cells at 2 h was 2.96% ± 0.35%, which could be substantially blocked by an excessive amount of RBD, and drop to 1.71% ± 0.23%. In BALB/c mice, the biodistribution of 124I-RBD after intravenous injection showed a moderate metabolism rate, and its 24 h-post injection (p.i.) organ distribution was similar to the expression profile in body. Micro-PET imaging of mice after intrapulmonary injection showed high uptake of lung at 1, 4, 24 h p.i.. In conclusion, the experimental results demonstrate the potential of 124I-RBD as a novel targeted molecular probe for COVID-19. This probe may be used for non-invasive ACE2 mapping in mammals.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Animals , Mammals/metabolism , Mice , Protein Binding , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Tissue Distribution
11.
Atmospheric Measurement Techniques ; 14(11):7297-7327, 2021.
Article in English | ProQuest Central | ID: covidwho-1528983

ABSTRACT

Launched in October 2017, the TROPOspheric Monitoring Instrument (TROPOMI) aboard Sentinel-5 Precursor provides the potential to monitor air quality over point sources across the globe with a spatial resolution as high as 5.5 km × 3.5 km (7 km × 3.5 km before 6 August 2019). The DLR nitrogen dioxide (NO2) retrieval algorithm for the TROPOMI instrument consists of three steps: the spectral fitting of the slant column, the separation of stratospheric and tropospheric contributions, and the conversion of the slant column to a vertical column using an air mass factor (AMF) calculation. In this work, an improved DLR tropospheric NO2 retrieval algorithm from TROPOMI measurements over Europe is presented. The stratospheric estimation is implemented using the STRatospheric Estimation Algorithm from Mainz (STREAM), which was developed as a verification algorithm for TROPOMI and does not require chemistry transport model data as input. A directionally dependent STREAM (DSTREAM) is developed to correct for the dependency of the stratospheric NO2 on the viewing geometry by up to 2×1014 molec./cm2. Applied to synthetic TROPOMI data, the uncertainty in the stratospheric column is 3.5×1014 molec./cm2 in the case of significant tropospheric sources. Applied to actual measurements, the smooth variation of stratospheric NO2 at low latitudes is conserved, and stronger stratospheric variation at higher latitudes is captured.For AMF calculation, the climatological surface albedo data are replaced by geometry-dependent effective Lambertian equivalent reflectivity (GE_LER) obtained directly from TROPOMI measurements with a high spatial resolution. Mesoscale-resolution a priori NO2 profiles are obtained from the regional POLYPHEMUS/DLR chemistry transport model with the TNO-MACC emission inventory. Based on the latest TROPOMI operational cloud parameters, a more realistic cloud treatment is provided by a Clouds-As-Layers (CAL) model, which treats the clouds as uniform layers of water droplets, instead of the Clouds-As-Reflecting-Boundaries (CRB) model, in which clouds are simplified as Lambertian reflectors.For the error analysis, the tropospheric AMF uncertainty, which is the largest source of NO2 uncertainty for polluted scenarios, ranges between 20 % and 50 %, leading to a total uncertainty in the tropospheric NO2 column in the 30 %–60 % range. From a validation performed with ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements, the new DLR tropospheric NO2 data show good correlations for nine European urban/suburban stations, with an average correlation coefficient of 0.78. The implementation of the algorithm improvements leads to a decrease of the relative difference from -55.3 % to -34.7 % on average in comparison with the DLR reference retrieval. When the satellite averaging kernels are used to remove the contribution of a priori profile shape, the relative difference decreases further to ∼ -20 %.

12.
Journal of Building Engineering ; : 103246, 2021.
Article in English | ScienceDirect | ID: covidwho-1433566

ABSTRACT

According to the discussion of the design method and operational effect for Wuhan Huoshenshan Hospital, this paper summarized the design control points of indoor and outdoor environment of COVID-19 emergency hospital. Based on the design of Wuhan Huoshenshan Hospital, this paper analyzed and discussed the site design, building layout, three-zones and two-passages, the design scheme of the ventilation and air conditioning system for negative pressure ward and negative pressure isolation ward, air distribution, as well as some other key designs for COVID-19 emergency hospital. The design points were summarized and refined. The design methods and technology requirements of the COVID-19 emergency hospital were provided in this study, such as ventilation and air conditioning system setting, ventilation quantity of wards, pressure gradient control measures among different areas, upper and lower air distribution, filter setting mode and distance of air inlet and outlet, which could benefit to provide references for the design of similar projects in the future.

13.
Air Qual Atmos Health ; 14(11): 1737-1755, 2021.
Article in English | MEDLINE | ID: covidwho-1384597

ABSTRACT

Since its first confirmed case in December 2019, coronavirus disease 2019 (COVID-19) has become a worldwide pandemic with more than 90 million confirmed cases by January 2021. Countries around the world have enforced lockdown measures to prevent the spread of the virus, introducing a temporal change of air pollutants such as nitrogen dioxide (NO2) that are strongly related to transportation, industry, and energy. In this study, NO2 variations over regions with strong responses to COVID-19 are analysed using datasets from the Global Ozone Monitoring Experiment-2 (GOME-2) sensor aboard the EUMETSAT Metop satellites and TROPOspheric Monitoring Instrument (TROPOMI) aboard the EU/ESA Sentinel-5 Precursor satellite. The global GOME-2 and TROPOMI NO2 datasets are generated at the German Aerospace Center (DLR) using harmonized retrieval algorithms; potential influences of the long-term trend and seasonal cycle, as well as the short-term meteorological variation, are taken into account statistically. We present the application of the GOME-2 data to analyze the lockdown-related NO2 variations for morning conditions. Consistent NO2 variations are observed for the GOME-2 measurements and the early afternoon TROPOMI data: regions with strong social responses to COVID-19 in Asia, Europe, North America, and South America show strong NO2 reductions of ∼ 30-50% on average due to restriction of social and economic activities, followed by a gradual rebound with lifted restriction measures. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11869-021-01046-2.

14.
Biomed J ; 44(5): 582-588, 2021 10.
Article in English | MEDLINE | ID: covidwho-1347505

ABSTRACT

BACKGROUND: Unequal access to healthcare is a global medical problem. Telemedicine, recently made possible by technological advances, may mitigate this inequity. However, the usefulness of telemedicine for procedure-driven disciplines, such as otolaryngology, under infectious conditions (e.g., the COVID-19 pandemic) is unknown. METHODS: Telemedicine was made legal in Taiwan by an amendment to the Physician Act in 2018. Kaohsiung Chang Gung Memorial Hospital was the first hospital in Taiwan to provide the telemedicine service by connecting to the Chenggong Branch of Taitung Hospital (CGBTH) in November 2018. This retrospective cohort study included all new and established otolaryngology outpatient consultations between November 2018 and May 2020 at CGBTH. The Current Procedural Terminology and International Classification of Disease, 10th Revision codes, patient demographic data, and questionnaire data were obtained. RESULTS: The study included 123 patients with 218 encounters over 19 months. The majority of complaints were ear-related (52.6%). Overall, 49% of the encounters required a specialized procedure for diagnosis and treatment; of these, cerumen removal was the most common procedure. The patient subjective improvement rate increased over the study period (from 62.0% to 78.9%). The rates of return and case closure were both around 90% in 2018 and 2019. The number of otolaryngology consultations and rate of return declined after the start of the COVID-19 pandemic; however, the subjective improvement and case closure rates remained stable. The telemedicine service saved at least 2 h driving time per visit. CONCLUSION: Telemedicine for otolaryngology is a promising approach for remote and underserved regions, as well as during an infectious disease pandemic.


Subject(s)
COVID-19 , Otolaryngology , Telemedicine , Humans , Pandemics , Retrospective Studies , SARS-CoV-2 , Taiwan/epidemiology
15.
Environmental Research Letters ; 16(7), 2021.
Article in English | ProQuest Central | ID: covidwho-1317875

ABSTRACT

Coronavirus disease 2019 (COVID-19) pandemic has led to a rare reduction in human activities. In such a background, data from ground-based environmental stations, satellites, and reanalysis materials are utilized to conduct a comprehensive analysis of the global air quality changes during the COVID-19 outbreak. The results showed that under the impact of the COVID-19 outbreak, a significant decrease in particulate matter (PM x ) and nitrogen dioxide (NO2) occurred in more than 40% of the world’s land area, with NO2 (PM x ) decreasing by ∼30% (∼20%). The mobility, meteorological factors, and the response speed to COVID-19 outbreaks were examined. It was further found that in quick-response cities, lockdowns produced a sharp decline in mobility and had a dominant impact on air quality. In contrast, in slow-response cities, mobility dropped gradually since the confirmation of the first COVID-19 case (FCC) and he impact of the FCC, lockdowns, and meteorological factors were comparable.

16.
BMC Infect Dis ; 21(1): 325, 2021 Apr 07.
Article in English | MEDLINE | ID: covidwho-1172826

ABSTRACT

BACKGROUND: Rapid and simple serological assays for characterizing antibody responses are important in the current COVID-19 pandemic caused by SARS-CoV-2. Multiplex immunoblot (IB) assays termed COVID-19 IB assays were developed for detecting IgG and IgM antibodies to SARS-CoV-2 virus proteins in COVID-19 patients. METHODS: Recombinant nucleocapsid protein and the S1, S2 and receptor binding domain (RBD) of the spike protein of SARS-CoV-2 were used as target antigens in the COVID-19 IBs. Specificity of the IB assay was established with 231 sera from persons with allergy, unrelated viral infections, autoimmune conditions and suspected tick-borne diseases, and 32 goat antisera to human influenza proteins. IgG and IgM COVID-19 IBs assays were performed on 84 sera obtained at different times after a positive RT-qPCR test from 37 COVID-19 patients with mild symptoms. RESULTS: Criteria for determining overall IgG and IgM antibody positivity using the four SARS-CoV-2 proteins were developed by optimizing specificity and sensitivity in the COVID-19 IgG and IgM IB assays. The estimated sensitivities and specificities of the COVID-19 IgG and IgM IBs for IgG and IgM antibodies individually or for either IgG or IgM antibodies meet the US recommendations for laboratory serological diagnostic tests. The proportion of IgM-positive sera from the COVID-19 patients following an RT-qPCR positive test was maximal at 83% before 10 days and decreased to 0% after 100 days, while the proportions of IgG-positive sera tended to plateau between days 11 and 65 at 78-100% and fall to 44% after 100 days. Detection of either IgG or IgM antibodies was better than IgG or IgM alone for assessing seroconversion in COVID-19. Both IgG and IgM antibodies detected RBD less frequently than S1, S2 and N proteins. CONCLUSIONS: The multiplex COVID-19 IB assays offer many advantages for simultaneously evaluating antibody responses to different SARS-CoV-2 proteins in COVID-19 patients.


Subject(s)
Antibodies, Viral/blood , Antibody Formation , COVID-19/blood , Coronavirus Nucleocapsid Proteins/immunology , Spike Glycoprotein, Coronavirus/immunology , Humans , Immunoblotting , Immunoglobulin G/blood , Immunoglobulin M/blood , Pandemics , Phosphoproteins/immunology , Sensitivity and Specificity , Seroconversion , Serologic Tests
17.
Clin Infect Dis ; 71(16): 2158-2166, 2020 11 19.
Article in English | MEDLINE | ID: covidwho-1153176

ABSTRACT

BACKGROUND: In December 2019, the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) broke out in Wuhan. Epidemiological and clinical characteristics of patients with COVID-19 have been reported, but the relationships between laboratory features and viral load has not been comprehensively described. METHODS: Adult inpatients (≥18 years old) with COVID-19 who underwent multiple (≥5 times) nucleic acid tests with nasal and pharyngeal swabs were recruited from Renmin Hospital of Wuhan University, including general patients (n = 70), severe patients (n = 195), and critical patients (n = 43). Laboratory data, demographic data, and clinical data were extracted from electronic medical records. The fitted polynomial curve was used to explore the association between serial viral loads and illness severity. RESULTS: Viral load of SARS-CoV-2 peaked within the first few days (2-4 days) after admission, then decreased rapidly along with virus rebound under treatment. Critical patients had the highest viral loads, in contrast to the general patients showing the lowest viral loads. The viral loads were higher in sputum compared with nasal and pharyngeal swab (P = .026). The positive rate of respiratory tract samples was significantly higher than that of gastrointestinal tract samples (P < .001). The SARS-CoV-2 viral load was negatively correlated with portion parameters of blood routine and lymphocyte subsets and was positively associated with laboratory features of cardiovascular system. CONCLUSIONS: The serial viral loads of patients revealed whole viral shedding during hospitalization and the resurgence of virus during the treatment, which could be used for early warning of illness severity, thus improve antiviral interventions.


Subject(s)
COVID-19/epidemiology , Coronavirus/pathogenicity , China/epidemiology , Female , Humans , Male , Serologic Tests , Viral Load
18.
Remote Sensing ; 13(5):969-969, 2021.
Article in English | Academic Search Complete | ID: covidwho-1138749

ABSTRACT

In this paper, we present the estimation of surface NO 2 concentrations over Germany using a machine learning approach. TROPOMI satellite observations of tropospheric NO 2 vertical column densities (VCDs) and several meteorological parameters are used to train the neural network model for the prediction of surface NO 2 concentrations. The neural network model is validated against ground-based in situ air quality monitoring network measurements and regional chemical transport model (CTM) simulations. Neural network estimation of surface NO 2 concentrations show good agreement with in situ monitor data with Pearson correlation coefficient (R) of 0.80. The results also show that the machine learning approach is performing better than regional CTM simulations in predicting surface NO 2 concentrations. We also performed a sensitivity analysis for each input parameter of the neural network model. The validated neural network model is then used to estimate surface NO 2 concentrations over Germany from 2018 to 2020. Estimated surface NO 2 concentrations are used to investigate the spatio-temporal characteristics, such as seasonal and weekly variations of NO 2 in Germany. The estimated surface NO 2 concentrations provide comprehensive information of NO 2 spatial distribution which is very useful for exposure estimation. We estimated the annual average NO 2 exposure for 2018, 2019 and 2020 is 15.53, 15.24 and 13.27 µ g/m 3 , respectively. While the annual average NO 2 concentration of 2018, 2019 and 2020 is only 12.79, 12.60 and 11.15 µ g/m 3 . In addition, we used the surface NO 2 data set to investigate the impacts of the coronavirus disease 2019 (COVID-19) pandemic on ambient NO 2 levels in Germany. In general, 10–30% lower surface NO 2 concentrations are observed in 2020 compared to 2018 and 2019, indicating the significant impacts of a series of restriction measures to reduce the spread of the virus. [ABSTRACT FROM AUTHOR] Copyright of Remote Sensing is the property of MDPI Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

19.
Int J Med Sci ; 18(1): 270-275, 2021.
Article in English | MEDLINE | ID: covidwho-994131

ABSTRACT

Rationale: To identify whether the initial chest computed tomography (CT) findings of patients with coronavirus disease 2019 (COVID-19) are helpful for predicting the clinical outcome. Methods: A total of 224 patients with laboratory-confirmed COVID-19 who underwent chest CT examination within the first day of admission were enrolled. CT findings, including the pattern and distribution of opacities, the number of lung lobes involved and the chest CT scores of lung involvement, were assessed. Independent predictors of adverse clinical outcomes were determined by multivariate regression analysis. Adverse outcome were defined as the need for mechanical ventilation or death. Results: Of 224 patients, 74 (33%) had adverse outcomes and 150 (67%) had good outcomes. There were higher frequencies of more than four lung zones involved (73% vs 32%), both central and peripheral distribution (57% vs 42%), consolidation (27% vs 17%), and air bronchogram (24% vs 13%) and higher initial chest CT scores (8.6±3.4 vs 5.4±2.1) (P < 0.05 for all) in the patients with poor outcomes. Multivariate analysis demonstrated that more than four lung zones (odds ratio [OR] 3.93; 95% confidence interval [CI]: 1.44 to 12.89), age above 65 (OR 3.65; 95% CI: 1.11 to 10.59), the presence of comorbidity (OR 5.21; 95% CI: 1.64 to 19.22) and dyspnea on admission (OR 3.19; 95% CI: 1.35 to 8.46) were independent predictors of poor outcome. Conclusions: Involvement of more than four lung zones and a higher CT score on the initial chest CT were significantly associated with adverse clinical outcome. Initial chest CT findings may be helpful for predicting clinical outcome in patients with COVID-19.


Subject(s)
COVID-19/diagnostic imaging , Radiography, Thoracic , Tomography, X-Ray Computed , Adult , Aged , Humans , Middle Aged , Prognosis , Retrospective Studies
20.
Curr Med Res Opin ; 36(11): 1747-1752, 2020 11.
Article in English | MEDLINE | ID: covidwho-799955

ABSTRACT

OBJECTIVE: Coronavirus disease 2019 (COVID-19) has high morbidity and mortality, and spreads rapidly in the community to result in a large number of infection cases. This study aimed to compare clinical features in adult patients with coronavirus disease 2019 (COVID-19) pneumonia to those in adult patients with community-acquired pneumonia (CAP). METHODS: Clinical presentations, laboratory findings, imaging features, complications, treatment and outcomes were compared between patients with COVID-19 pneumonia and patients with CAP. The study group of patients with COVID-19 pneumonia consisted of 120 patients. One hundred and thirty-four patients with CAP were enrolled for comparison. RESULTS: Patients with COVID-19 pneumonia had lower levels of abnormal laboratory parameters (white blood cell count, lymphocyte count, procalcitonin level, erythrocyte sedimentation rate and C-reactive protein level) and more extensive radiographic involvement. More severe respiratory compromise resulted in a higher rate of intensive care unit admission, acute respiratory distress syndrome (ARDS) and mechanical ventilation (36% vs 15%, 34% vs 15% and 32% vs 12%, respectively; all p < .05). The 30 day mortality was more than twice as high in patients with COVID-19 pneumonia (12% versus 5%; p = .063), despite not reaching a statistically significant difference. CONCLUSIONS: Lower levels of abnormal laboratory parameters, more extensive radiographic involvement, more severe respiratory compromise, and higher rates of ICU admission, ARDS and mechanical ventilation are key characteristics that distinguish patients with COVID-19-associated pneumonia from patients with CAP.


Subject(s)
Betacoronavirus , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Adult , Aged , COVID-19 , Case-Control Studies , China/epidemiology , Community-Acquired Infections/complications , Community-Acquired Infections/diagnosis , Community-Acquired Infections/mortality , Community-Acquired Infections/therapy , Coronavirus Infections/complications , Coronavirus Infections/mortality , Coronavirus Infections/therapy , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/complications , Pneumonia, Viral/mortality , Pneumonia, Viral/therapy , Prognosis , Retrospective Studies , SARS-CoV-2 , Severity of Illness Index
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