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1.
Frontiers in immunology ; 13, 2022.
Article Dans Anglais | EuropePMC | ID: covidwho-2074008

Résumé

COVID-19 prognoses suggests that a proportion of patients develop fibrosis, but there is no evidence to indicate whether patients have progression of mesenchymal transition (MT) in the lungs. The role of MT during the COVID-19 pandemic remains poorly understood. Using single-cell RNA sequencing, we profiled the transcriptomes of cells from the lungs of healthy individuals (n = 45), COVID-19 patients (n = 58), and idiopathic pulmonary fibrosis (IPF) patients (n = 64) human lungs to map the entire MT change. This analysis enabled us to map all high-resolution matrix-producing cells and identify distinct subpopulations of endothelial cells (ECs) and epithelial cells as the primary cellular sources of MT clusters during COVID-19. For the first time, we have identied early and late subgroups of endothelial mesenchymal transition (EndMT) and epithelial-mesenchymal transition (EMT) using analysis of public databases for single-cell sequencing. We assessed epithelial subgroups by age, smoking status, and gender, and the data suggest that the proportional changes in EMT in COVID-19 are statistically significant. Further enumeration of early and late EMT suggests a correlation between invasive genes and COVID-19. Finally, EndMT is upregulated in COVID-19 patients and enriched for more inflammatory cytokines. Further, by classifying EndMT as early or late stages, we found that early EndMT was positively correlated with entry factors but this was not true for late EndMT. Exploring the MT state of may help to mitigate the fibrosis impact of SARS-CoV-2 infection.

2.
Hygiene and Environmental Health Advances ; 3:100015-100015, 2022.
Article Dans Anglais | EuropePMC | ID: covidwho-2010630

Résumé

Image, graphical

3.
Disease Surveillance ; 37(6):720-724, 2022.
Article Dans Chinois | CAB Abstracts | ID: covidwho-2055479

Résumé

Objective: To assess the risk of public health emergencies, including both indigenous and imported ones, which might occur in the mainland of China in June 2022.

4.
Hygiene and Environmental Health Advances ; : 100015, 2022.
Article Dans Anglais | ScienceDirect | ID: covidwho-1914430

Résumé

Smart classrooms are a relatively confined public space for college students. SARS-COV-2 and other respiratory viruses have been shown to pose a more significant threat to human health in relatively confined spaces. Using numerical simulation method to simulate the transmission and concentration distribution of virus-carrying droplets in smart classrooms in three different seasons (summer, winter, transitional seasons: spring and autumn). The Realizable k-ε model is used to simulate the airflow pattern in the smart classroom, and the Lagrangian method is used to simulate the transmission of droplets. The transmission process of droplets produced from the teacher standing on the platform and the student sitting on the seat is studied. The influence of three kinds of outdoor temperature on droplet transmission and the body deposition fraction of people in the smart classroom is analyzed. The results show that droplet transmission speed is maximum at the temperature of 5 degrees when the outdoor temperature is 5 °C, 20 °C, and 35 °C respectively. At 10 s, the transmission distance of droplets increases by 9.55% compared with that at 20 °C and 10.31% compared with that at 35 °C. In addition, the body deposition fraction is also affected by the location of the vent, with downwind contact being 6 times more likely than upwind contact. The research results can provide suggestions and measures for epidemic prevention and control in smart classrooms.

5.
Smartmat ; 3(2):226-248, 2022.
Article Dans Anglais | ProQuest Central | ID: covidwho-1905951

Résumé

Due to the COVID‐19 pandemic, many rapid antimicrobial agents have developed intensively. Carbon dots (CDs), a new type of carbon‐based nanomaterials, shows great potential against emerging infectious diseases and antimicrobial‐resistant infections due to their unique optical properties, excellent biocompatibility, and easy surface modification. With the definition of the CDs structure and properties, synthesis, and characteristic technology improvement, the research on the CDs as antimicrobial agents has made significant progress. However, the lack of high repeatable and exact preparation methods, and the regular antimicrobial activity make it far from practical application. In this review, we summarize the most recent progress and challenges of CDs antimicrobial. First, an overview of the characteristics and properties is given, and the advantage of CDs applied to antimicrobial is further discussed. Then, it focuses on research progress on antimicrobial mechanisms under different conditions, the critical factors affecting their antimicrobial activity, and the practical antimicrobial applications. Finally, the main challenges and future research perspectives of antimicrobial CDs are proposed.

6.
Frontiers in pharmacology ; 13, 2022.
Article Dans Anglais | EuropePMC | ID: covidwho-1876649

Résumé

Acute lung injury (ALI) or its aggravated stage acute respiratory distress syndrome (ARDS) is a common severe clinical syndrome in intensive care unit, may lead to a life-threatening form of respiratory failure, resulting in high mortality up to 30–40% in most studies. Nanotechnology-mediated anti-inflammatory therapy is an emerging novel strategy for the treatment of ALI, has been demonstrated with unique advantages in solving the dilemma of ALI drug therapy. Artesunate (ART), a derivative of artemisinin, has been reported to have anti-inflammatory effects. Therefore, in the present study, we designed and synthesized PEGylated ART prodrugs and assessed whether ART prodrugs could attenuate lipopolysaccharide (LPS) induced ALI in vitro and in vivo. All treatment groups were conditioned with ART prodrugs 1 h before challenge with LPS. Significant increased inflammatory cytokines production and decreased GSH levels were observed in the LPS stimulated mouse macrophage cell line RAW264.7. Lung histopathological changes, lung W/D ratio, MPO activity and total neutrophil counts were increased in the LPS-induced murine model of ALI via nasal administration. However, these results can be reversed to some extent by treatment of ART prodrugs. The effectiveness of mPEG2k-SS-ART in inhibition of ALI induced by LPS was confirmed. In conclusion, our results demonstrated that the ART prodrugs could attenuate LPS-induced ALI effectively, and mPEG2k-SS-ART may serve as a novel strategy for treatment of inflammation induced lung injury.

7.
Preprint Dans Anglais | medRxiv | ID: ppmedrxiv-22276789

Résumé

BackgroundMany people have experienced a high burden due to the spread of the coronavirus disease (COVID-19) and its serious consequences for health and everyday life. Prior studies have reported that physical activity (PA) may lower the risk of COVID-19 hospitalization. The present meta-analysis (PROSPERO registration number: CRD42022339672) explored the dose- response relationship between PA and the risk of COVID-19 hospitalization. MethodsEpidemiological observational studies on the relationship between PA and the risk of COVID-19 hospitalization were included. Categorical dose-response relationships between PA and the risk of COVID-19 hospitalization were assessed using random effect models. Robust error meta-regression models assessed the continuous relationship between PA (metabolic equivalent [MET]-h/week) and COVID-19 hospitalization risk across studies reporting quantitative PA estimates. ResultsSeventeen observational studies (cohort\case-control\cross-section) met the criteria for inclusion in the meta-analysis. Categorical dose-relationship analysis showed a 40% (risk ratio (RR) 0.60, 95% confidence intervals (CI): 0.48-0.71) reduction in the risk of COVID-19 hospitalization compared to the lowest dose of PA. The results of the continuous dose-response relationship showed a non-linear inverse relationship (Pnon-linearity < 0.05) between PA and the risk of COVID-19 hospitalization. When total PA was less than or greater than 10 Met-h/week, an increase of 4 Met-h/week was associated with a 14% (RR = 0.83, 95%CI: 0.85-0.87) and 11% (RR = 0.89, 95%CI: 0.87-0.90) reduction in the risk of COVID-19 hospitalization, respectively. ConclusionsThere was an inverse non-linear dose-response relationship between PA level and the risk of COVID-19 hospitalization. Doses of the guideline-recommended minimum PA levels by WTO may be required for more substantial reductions in the COVID-19 hospitalization risk.

8.
Energies ; 15(11):3927, 2022.
Article Dans Anglais | MDPI | ID: covidwho-1869527

Résumé

To obtain the price return and price volatility spillovers between renewable energy stocks, technology stocks, oil futures and carbon allowances under different investment horizons, this paper employs a frequency-dependent method to study the dynamic connectedness between these assets in four frequency bands. The results show that, first, there is a strong spillover effect between these assets from a system-wide perspective, and it's mainly driven by short-term spillovers. Second, in the time domain, technology stocks have a more significant impact on renewable energy stocks compared to crude oil. However, through the study in the frequency domain, we find renewable energy stocks exhibit a more complex relationship with the other two assets at different time scales. Third, renewable energy stocks have significant spillover effect on carbon prices only in the short term. On longer time scales, other factors such as energy prices, climate and policy may have a greater impact on carbon allowance prices. Fourth, the spillover effect of the system is time-varying and frequency-varying. During the European debt crisis, the international oil price decline and the COVID-19 pandemic, the total spillover index of the system has experienced a substantial increase, mainly driven by medium, medium to long or long term spillovers.

9.
EuropePMC; 2022.
Preprint Dans Anglais | EuropePMC | ID: ppcovidwho-332913

Résumé

Cells and tissues respond to perturbations in multiple ways that can be sensitively reflected in alterations of gene expression. Current approaches to finding and quantifying the effects of perturbations on cell-level responses over time disregard the temporal consistency of identifiable gene programs. To leverage the occurrence of these patterns for perturbation analyses, we developed CellDrift (https://github.com/KANG-BIOINFO/CellDrift), a generalized linear model-based functional data analysis method capable of identifying covarying temporal patterns of various cell types in response to perturbations. As compared to several other approaches, CellDrift demonstrated superior performance in the identification of temporally varied perturbation patterns and the ability to impute missing time points. We applied CellDrift to multiple longitudinal datasets, including COVID-19 disease progression and gastrointestinal tract development, and demonstrated its ability to identify specific gene programs associated with sequential biological processes, trajectories, and outcomes.

10.
Aerosol and Air Quality Research ; 21(8), 2021.
Article Dans Anglais | ProQuest Central | ID: covidwho-1771441

Résumé

In closed buses, the spread of droplets with viruses/bacteria may cause the spread of respiratory infectious diseases. Discrete phase modeling is used to simulate the diffusion characteristics and concentration distribution of droplets at different temperatures and different exhalation positions by ANSYS FLUENT software. The integral concentration of droplets at different locations can be quantified, which leads to identification of low-risk areas and high-risk areas in the bus. Results show that a higher outdoor temperature leads to lower droplets’ diffusion speed and longer time until the droplets reach the driver. In addition, based on the integral concentration of droplets at the seats, regardless of whether a passenger exhales droplets in the front row of the bus, the position of the rear door or the last row of the bus, the seats in the last row of the bus away from the door belong to the low-risk area. In contrast, the seats near the door and the middle seat in the bus are higher risk areas. Consequently, this study proposed sitting on a seat in the low-risk area as a means to reduce the risk of passengers. Moreover, safety protection facilities around the driver should be modified to improve the isolation of the upper area of the driver’s location, so as to effectively prevent the droplet diffusion towards the driver, thereby effectively reducing the driver’s risk of infection.

11.
Public Performance & Management Review ; : 1-24, 2022.
Article Dans Anglais | Taylor & Francis | ID: covidwho-1711281
12.
EuropePMC; 2021.
Preprint Dans Anglais | EuropePMC | ID: ppcovidwho-325389

Résumé

Background: Recent evidences have shown that gut microbiome of patients with COVID-19 significantly changes and can reflect the severity of the disease. And gut microbiota richness was not restored to normal levels after 6-month recovery. However, SARS-CoV-2 primarily infects the respiratory tract, few studies investigate whether the alterations of oropharyngeal microbiome is associated with disease severity in patients with COVID-19, and whether interferences in microbiome composition, if any, eliminate with clearance of the SARS-CoV-2 virus. We employed metatranscriptomic sequencing to analyse oropharyngeal swabs collected within a week of diagnosis COVID-19 (period of disease group: PDG) and two months after clearance of the SARS-CoV-2 virus (convalescent group: CG) from 47 patients with COVID-19. Meanwhile, oropharyngeal swabs from 40 healthy subjects were analyzed as healthy control group (HCG). Results: : Oropharyngeal microbial composition was significantly altered in patients with COVID-19 compared with healthy controls even two months after clearance of the SARS-CoV-2 virus. Little changes in α-diversity among HCG, PDG and CG ( P >0.05), but obviously changes in β-diversity among them. Notably, Prevotella increased significantly in PDG than that in HCG (Wilcoxon rank-sum test, P <0.001) and increased gradually along with the severity of patients with COVID-19 aggravated. There was a positive correlation between Prevotella and the elevation of Neutrophil percentage (R = 0.301, P = 0.040). Similarly, SARS-CoV-2 and Aspergillus increased remarkably in critical Patients with COVID-19. There was a negative correlation between SARS-CoV-2 viral load and platelet counts (R = −0.330, P = 0.022). Conclusions: : The oropharyngeal microbiome in patients with COVID-19 present persistent dysbiosis even two months after clearance of the SARS-CoV-2 virus. Furthermore, alterations in oropharyngeal microbial composition reflected the severity of disease in patients with COVID-19. Our findings underscore that there is an urgent need to understand the specific roles of oropharyngeal microorganisms in COVID-19 disease progression and rehabilitation.

13.
EuropePMC; 2020.
Preprint Dans Anglais | EuropePMC | ID: ppcovidwho-323626

Résumé

Background: Coronavirus disease 2019(COVID-19) is a worldwide pandemic.In this study, we aimed to evaluate the risk factors of death from severe and critical COVID-19 patients. Method: A retrospective study of patients diagnosed with severe and critical COVID-19 from four hospitals in Wuhan, China, describing the clinical characteristics and laboratory results, and using Cox regression to study the risk factors was conducted. Results: Four hundred and forty-six patients with COVID-19 showed a high case fatality rate(CFR)(20.2%). All patients required oxygen therapy, and 52(12%) patients required invasive mechanical ventilation,of which 50(96%) patients died.The univariate Cox proportional hazard model showed a white blood cell count of more than 10 × 10⁹/L(HR3.903,95%CI 2.413 to 6.313),patients’ risk of death significantly increased.The multivariate Cox proportional hazard model demonstrated that older age (HR 1.074, 95% CI 1.050 to 1.098) was an independent risk factor and high white blood cell count(HR 1.119, 95% CI 1.056 to 1.186)was a predictive factor for COVID-19 on admission. Conclusions: COVID-19 is a new disease entity that carries significant risk of morbidity and CFR.Older age was an independent risk factor and high white blood cell was a predictive factor for COVID-19.

14.
EuropePMC; 2020.
Preprint Dans Anglais | EuropePMC | ID: ppcovidwho-323553

Résumé

Background: Coronavirus Disease 2019 (COVID-19) is a novel infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan and has quickly spread across the world. The mortality rate in critically ill patients with COVID-19 is high. This study analyzed clinical and biochemical parameters between mild and severe patients, helping to identify severe or critical patients early. Methods: : In this single center, cross-sectional study, 143 patients were included and divided to mild/moderate and sever/critical groups. Correlation between the disease criticality and clinical features and peripheral blood biochemical markers was analyzed. Cut-off values for critically ill patients were speculated through the ROC curve. Results: : Significantly, disease severity was associated with age (r = 0.458, P < 0.001) , comorbidities (r = 0.445, P < 0.001) , white cell counts (r = 0.229, P = 0.006) , neutrophil count (r = 0.238, P = 0.004) , lymphocyte count (r = -0.295, P < 0.001) , albumin (r = -0.603, P < 0.001) , high-density lipoprotein cholesterol (r= -0.362, P < 0.001) , serum potassium (r = -0.237, P = 0.004) , plasma glucose (r = 0.383, P < 0.001) , total bilirubin (r = 0.340, P < 0.001) , serum amyloid A (r = 0.58, P < 0.001) , procalcitonin (r = 0.345, P < 0.001) , C-reactive protein ( r = 0.477, P < 0.001) , lactate dehydrogenase (r = 0.548, P < 0.001) , aspartate aminotransferase (r = 0.342, P < 0.001) , alanine aminotransferase (r = 0.264, P = 0.001) , erythrocyte sedimentation rate (r = 0.284, P = 0.001) and D-dimer (r = 0.477, P < 0.001) . Conclusion: With following parameters such as age > 52 years, C-reactive protein > 64.79 mg/L, lactate dehydrogenase > 245 U/L, D-dimer > 0.96 ug/mL, serum amyloid A > 100.02 mg/L, or albumin < 36 g/L, the progress of COVID-19 to critical stage should be closely observed and possibly prevented. Lymphocyte count, serum potassium and procalcitonin may also be a prognostic indicator.

15.
EuropePMC; 2020.
Preprint Dans Anglais | EuropePMC | ID: ppcovidwho-323552

Résumé

Background: Coronavirus disease 2019 ( COVID-19 ) is a novel infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan and has quickly spread across the world. The mortality rate in critically ill patients with COVID-19 is high. This study analyzed clinical and biochemical parameters between mild and severe patients, helping to identify severe or critical patients early. Methods: In this single center, cross-sectional study, 143 patients were included and divided to mild/moderate and sever/critical groups. Correlation between the disease criticality and clinical features and peripheral blood biochemical markers was analyzed. Cut-off values for critically ill patients were speculated through the ROC curve. Results: Significantly, disease severity was associated with age (r = 0.458, P < 0.001) , comorbidities (r = 0.445, P < 0.001) , white cell counts (r = 0.229, P = 0.006) , neutrophil count (r = 0.238, P = 0.004) , lymphocyte count (r = -0.295, P < 0.001) , albumin (r = -0.603, P < 0.001) , high-density lipoprotein cholesterol (r= -0.362, P < 0.001) , serum potassium (r = -0.237, P = 0.004) , plasma glucose (r = 0.383, P < 0.001) , total bilirubin (r = 0.340, P < 0.001) , serum amyloid A (r = 0.58, P < 0.001) , procalcitonin (r = 0.345, P < 0.001) , C-reactive protein ( r = 0.477, P < 0.001) , lactate dehydrogenase (r = 0.548, P < 0.001) , aspartate aminotransferase (r = 0.342, P < 0.001) , alanine aminotransferase (r = 0.264, P = 0.001) , erythrocyte sedimentation rate (r = 0.284, P = 0.001) and D-dimer (r = 0.477, P < 0.001) . Conclusion: With following parameters such as age > 52 years, C-reactive protein > 64.79 mg/L, lactate dehydrogenase > 245 U/L, D-dimer > 0.96 ug/mL, serum amyloid A > 100.02 mg/L, or a lbumin < 36 g/L, the progress of COVID-19 to critical stage should be closely observed and possibly prevented. Lymphocyte count, serum potassium and procalcitonin may also be a prognostic indicator .

16.
EuropePMC; 2020.
Preprint Dans Anglais | EuropePMC | ID: ppcovidwho-315680

Résumé

Background: COVID-19 is spreading rapidly intercity and international despite rigid public health prevention and control measures been taken. Case presentation : In a cluster of infection, six out of seven participants engaged in persistent singing and talking in confined space were later diagnosed COVID-19 patients. One of the cases was asymptomatic with no SARS-CoV-2 nucleic acid detected, but positive for anti-SARS-CoV-2 IgG. None of the household contacts was infected during the following month. Conclusions: This epidemiological evidence revealed that asymptomatic patients transmitted the coronavirus in confined space with relatively high efficiency, suggesting that it is important to provide better ventilation in public buildings to prevent COVID-19 transmission.

17.
EuropePMC; 2020.
Preprint Dans Anglais | EuropePMC | ID: ppcovidwho-307725

Résumé

Background: Online healthcare platform (OHP) is a new form of medical treatment, which solves the problems of unbalanced distribution of medical resources and expensive medical treatment in China. Especially under the epidemic of COVID-19, OHP has greatly reduced the medical pressure of the hospital and the risk of cross infection. Methods: : This paper uses evolutionary game theory to analyze behavioral strategies and their dynamic evolution in the promotion of OHP, and then numerical simulations are carried out with the help of program compilation. Results: : The results demonstrate that: (1) both the stricter qualification inspection of doctors and the more investment in information protection promote the participation of doctors and the use of patients;(2) with a higher initial probability of doctors joining, the possibility for patients in using OHP and platforms to provide standardized online healthcare services becomes higher;(3) if the initial probability of patients using is higher, the possibility for doctors to join OHP and platforms to provide standardized online healthcare services raises;(4) the trend of doctors joining the platform is affected by factors, such as registration cost, time cost, reputation loss ;(5) the tendency of patients in using online healthcare is mainly decided by the cost. Conclusions: : Based on theoretical analysis, this article takes the Spring Rain Doctor OHP as an example to verify the game results. Therefore, OHP should attach importance to the inspection of doctors and the protection of privacy information, and strengthen the publicity in remote places. At the same time OHP can promote the active participation of grassroots doctors, and set a reasonable evaluation mechanism, so as to popularize online medical treatment among patients further.

18.
Remote Sensing ; 14(4):921, 2022.
Article Dans Anglais | MDPI | ID: covidwho-1686932

Résumé

Under the threat of COVID-19, many regions around the world implemented lockdown policies to control the spread of the virus. This restriction on both social and economic activities has improved the quality of the environment in certain aspects. However, most previous studies have only focused on the short-term impact of lockdown policies on the urban environment. The long-term effects of lockdown require a more focused exploration and analysis. Thus, five major urban agglomerations in China were selected as the research area;changes in the numerical and spatial distribution of NO2 concentration and surface temperature during four different lockdown stages in 2019, 2020, and 2021 were investigated to analyze the long-term effects of lockdown policies on the urban environment. The results indicated that the impact of shorter lockdowns was short-term and unsustainable;the NO2 concentrations increased again with the resumption of production. Compared with air pollutants, thermal environmental problems are more complex. The effect of the lockdown policy was not reflected in the decrease in the area proportions of the high- and sub-high-temperature regions but rather in the spatial distribution of the high-temperature area, which was manifested as a fragmentation and dispersion of heat source patches. In addition to the severity of the lockdown, the impact of the lockdown policy was also closely related to the level of development and industrial structure of each city. Among the urban environments of the five agglomerations, the most affected were the Yangtze River Delta and Yangtze River Middle-Reach urban agglomerations, which had the largest decline in NO2 concentrations and the most notable fragmentation of heat source patches.

19.
Chinese Journal of Integrated Traditional and Western Medicine ; 41(3):330-337, 2021.
Article Dans Chinois | CAB Abstracts | ID: covidwho-1602741

Résumé

Objective: To explore the mechanism of Hanshi Zufei Formula (HSZFF) treating coronavirus disease 2019 (COVID-19) by the data mining analysis of network pharmacology and the molecular docking.

20.
Preprint Dans Anglais | bioRxiv | ID: ppbiorxiv-465996

Résumé

With the emergence of SARS-CoV-2 variants, there is urgent need to develop broadly neutralizing antibodies. Here, we isolate two VHH nanobodies (7A3 and 8A2) from dromedary camels by phage display, which have high affinity for the receptor-binding domain (RBD) and broad neutralization activities against SARS-CoV-2 and its emerging variants. Cryo-EM complex structures reveal that 8A2 binds the RBD in its up mode and 7A3 inhibits receptor binding by uniquely targeting a highly conserved and deeply buried site in the spike regardless of the RBD conformational state. 7A3 at a dose of [≥]5 mg/kg efficiently protects K18-hACE2 transgenic mice from the lethal challenge of B.1.351 or B.1.617.2, suggesting that the nanobody has promising therapeutic potentials to curb the COVID-19 surge with emerging SARS-CoV-2 variants. One-Sentence SummaryDromedary camel (Camelus dromedarius) VHH phage libraries were built for isolation of the nanobodies that broadly neutralize SARS-CoV-2 variants.

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