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1.
Zhongguo Jiguang/Chinese Journal of Lasers ; 49(20), 2022.
Article in Chinese | Scopus | ID: covidwho-2066650

ABSTRACT

Objective Since the outbreak of COVID-19, many hospitals have become overloaded with patients seeking examination, resulting in an imbalance between medical staff and patients. These high concentrations of people in hospital settings not only aggravate the risk of cross-infection among patients, but also stall the public medical system. Consequently, mild and chronic conditions cannot be treated effectively, and eventually develop into serious diseases. Therefore, the use of deep learning to accurately and efficiently analyze X-ray images for diagnostic purposes is crucial in alleviating the pressure on medical institutions during epidemics. The method developed in this study accurately detects dental X-ray lesions, thus enabling patients to self-diagnose dental conditions. Methods The method proposed in this study employs the YOLOV5 algorithm to detect lesion areas on digital X-ray images and optimize the network model's parameters. When hospitals and medical professionals collect and label training data, they use image normalization to enhance the images. Consequently, in combination with the network environment, parameters were adjusted into four modules in the YOLOV5 algorithm. In the Input module, Mosaic data enhancement and adaptive anchor box algorithms are used to generate the initial box. The focus component was added to the Backbone module, and a CSP structure was implemented to determine the image features. When the obtained image features are input into the Backbone module, the FPN and PAN structures are used to realize feature fusion. Subsequently, GIOU_Loss function is applied to the Head moudule, and NMS non-maximum suppression is used to generate a regression of results. Results and Discussions The proposed YOLOV5-based neural network yields satisfactory training and testing results. The training algorithm produced a recall rate of 95%, accuracy rate of 95%, and F1 score of 96%. All evaluation criteria are higher than those of the target detection algorithms of SSD and Faster-RCNN (Table 1). The network converges to smoothness after loss is reduced in the training process (Fig. 6), which proves that the network successfully learns the necessary features. Thus, the difference between predicted and real values is very small, which indicates good model performance. The mAP value of network training is 0.985 (Fig. 7), which proves that the network training meets the research requirements. Finally, an observation of the visualized thermodynamic diagram reveals that the network's region of interest matches the target detection region (Fig. 8). Conclusions This study proposes the use of the YOLOV5 algorithm for detecting lesions in dental X-ray images, training and testing on the dataset, modifying the network's nominal batch size, selecting an appropriate optimizer, adjusting the weight parameters, and modifying the learning rate attenuation strategy. The model's training results were compared with those of algorithms used in previous studies. Finally, the effect of feature extraction was analyzed after the thermodynamic diagram was visualized. The experimental results show that the algorithm model detects lesion areas with an accuracy rate of more than 95%, making it an effective autonomous diagnostic tool for patients. © 2022 Science Press. All rights reserved.

2.
Indoor Environmental Quality Performance Approaches (Iaq 2020), Pt 1 ; 2021.
Article in English | Web of Science | ID: covidwho-2040855

ABSTRACT

The sudden global outbreak of coronavirus diseases 2019 (COVID-19) has infected over seventy million people and resulted in over one million deaths by the end of 2020, posing a significant threat to human health. As potential carries of the novel coronavirus, exhaled airflow of infected individuals via coughs, are significant in virus transmission. This study measures human coughs' airflow velocity in a chamber filled with stage fog employing a particle image velocimetry (PIV) system. The purpose of this study is to examine and provide accurate boundary conditions for the prediction of the virus transmission routes using computational fluid dynamics (CFD) simulations. Sixty cough cases from ten healthy nonsmoking volunteers (five male and five female, averaged age of 29.3 +/- 4.0) are taken respectively, and ensemble-average operations are conducted to eliminate individual variations. Velocity distribution measurements are obtained in the vertical and horizontal planes around the mouth area. Temporal and spatial cough flow ensemble-averaged velocity profiles and standard deviations, cough duration time (CDT), peak velocity time (PVT), maximum cough velocities, and average spread angle of the cough jet are measured. Results show that the CDT of the cough airflow is 520-560 ms, and PVT is 20 ms. The male/ female averaged maximum velocity is 15.2/13.1 m/s, respectively. The average vertical/horizontal spread angle from the mouth is 15.3 degrees/13.3 degrees for males and 15.6 degrees/14.2 degrees for females, respectively. With the measurement data, it is possible to refine the initial boundary conditions of a simulated cough and model cough flows more accurately.

3.
7th International Conference on Distance Education and Learning, ICDEL 2022 ; : 184-189, 2022.
Article in English | Scopus | ID: covidwho-2020440

ABSTRACT

In the context of the COVID-19 pandemic, the paper focuses on discussing this important teaching segment online in blended learning. Taking the junior as the research objects, the behavioral characteristics and interaction depth of different types of students are studied through Cluster Analysis and Lag Sequence Analysis. The purposes are to dig out the problems existing in the online discussion process and to propose teachers' intervention suggestions so as to improve the effect of the discussion. The research found that discussion behavior is mainly construction, and there is no discussion mechanism with communication and interaction as knowledge development. The behavior transformation is mainly based on the priming-single type and priming-arguing type, and there are fewer students who achieve the ideal state of the argumentative type. Most students integrate into the discussion atmosphere slowly, so teachers should take corresponding measures to help students enter the discussion quickly at the beginning of the discussion. © 2022 ACM.

4.
IEEE Access ; 10:65854-65872, 2022.
Article in English | Scopus | ID: covidwho-1948718

ABSTRACT

The world is currently dealing with the aftermath of the coronavirus disease 2019 (COVID-19) pandemic, which has resulted in momentous changes, the likes of which had not been witnessed within the previous century. These adverse events and the resulting uncertainty have posed enormous challenges to organizations, and many are on the verge of collapse. Organizations urgently need to enhance their risk management abilities and capacity to cope with crises, and organizational resilience, as such a tool, has attracted widespread attention in China and abroad. The purpose of this study is to understand the research status and development trend of organizational resilience. In this study, we applied CiteSpace to perform a visual analysis. Searching for topics related to organizational resilience, we retrieved papers published from 1990-2022 in the Web of Science Core database. Second, we constructed an author, institution, and country/region collaboration network to identify the most prolific authors, institutions and countries, respectively. The distribution of core journals determined by journal co-citations, the document co-citation network, and a clustering analysis revealed the research topics and knowledge structure, the author co-citation network revealed which authors were influential, the keyword co-citation network indicated popular research topics, and the keyword bursts highlighted the research fields. This paper analyzes the main contributions of organizational resilience research at the author, institution, and country levels;knowledge sources;interdisciplinary characteristics and research areas in organizational resilience;and direction of future research. © 2013 IEEE.

5.
Neurology ; 98(18 SUPPL), 2022.
Article in English | EMBASE | ID: covidwho-1925543

ABSTRACT

Objective: To expand understanding of the human immunological response to SARS-CoV-2 vaccination in patients with Multiple Sclerosis (MS) treated with anti-CD20 monoclonal therapy and sphingosine-1-phosphate (S1P) modulators. Background: Immunomodulatory therapy prescribed for patients with MS has been associated with decreased or absent anti-SARS-CoV-2 immunoglobulin production following COVID-19 vaccination. We investigate broader adaptive immune responses to SARS-CoV-2 vaccination measuring IgG immunoglobulin production and T-cell reactivity in a small cohort. Design/Methods: We used the Stanford Research Repository database to identify 55 MS patients by ICD10 code who were tested for B-cell and T-cell responses via SARS-CoV-2-IgG and SARS-CoV-2 Interferon Gamma Release Assay (IGRA), respectively. 96% (53/55) of patients were fully vaccinated (98% mRNA/2% Janssen). A Chi-square test compared differences in vaccine response between 3 different disease modifying treatment (DMT) groups: anti-CD20 therapy (n=24), S1P modulators (n=11), and off DMT/other MS therapies (n=20). Results: In patients on anti-CD20 therapy, 71% (17/24) were positive for SARS-CoV-2 IGRA but negative for SARS-CoV-2 IgG, among which 65% (11/17) had low CD-19 levels (0-64 cells/uL, normal 100-500 cells/uL) with normal absolute lymphocyte count (ALC). Among patients who delayed vaccination by 4-6 months following anti-CD20 therapy, 13% (3/24) expressed SARS-CoV-2-IgG. 82% (9/11) of patients on S1P modulators showed absent SARS-CoV-2-IgG and SARS-CoV-2 IGRA responses, in association with low ALC (range 210-600 cells/uL, normal 1000-3000 cells/uL). 95% (19/20) of patients off DMT/on other MS therapies showed positive SARS-CoV-2-IgG and SARS-CoV-2 IRGA responses. All vaccinated patients were assessed between 4 weeks and 6 months post-vaccination. These differential responses between treatment groups were significant (p<0.05). Conclusions: We demonstrate that among MS patients treated with anti-CD20 therapy, T-cell response was largely preserved despite greatly reduced B-cell response to SARS-CoV-2 vaccination. MS patients on S1P modulators demonstrated absence of both B-cell and T-cell response. The clinical correlation of this is to be determined.

6.
Nephrology Dialysis Transplantation ; 37(SUPPL 3):i646-i647, 2022.
Article in English | EMBASE | ID: covidwho-1915775

ABSTRACT

BACKGROUND AND AIMS: Since the beginning of the COVID-19 pandemic in early 2020, >290 million people were infected by SARS-CoV-2 and >5.4 million have died from or with COVID-19 (https://coronavirus.jhu.edu/). Patients with chronic health conditions such as end-stage kidney disease (ESKD) experience particularly high morbidity and mortality because of COVID-19. ESKD patients on hemodialysis are widely vaccinated for hepatitis B (HBV) and seroconversion is routinely measured. This practice presents a rare opportunity to study immune function on a wide scale. It can be reasonably assumed that patients who are able to produce a vaccinal or post-HBV antibodies titers have a better immune function than those who are unable to mount such a serological response. We aim to jointly analyze results of SARS-CoV-2 RT-PCR and hepatitis B serology to determine if presence of vaccinal or post-HBV antibodies is associated with likelihood of developing COVID-19 infection. METHOD: Patients who were tested for COVID-19 at Fresenius Medical Care North America dialysis clinics from May 2020 to September 2020 were included in this analysis. HBV infection/vaccination status, demographic parameters and clinical parameters were obtained from the medical record. Nasopharyngeal swab specimen was tested via RT-PCR to detect presence of SARS-CoV-2. Patients were categorized as having good immune function or poor immune function based on vaccinal and post-HBV sero-status. Patients who were vaccinated against HBV but did not seroconvert were considered to have poor immune function. On the other hand, patients who mounted vaccinal or post-HBV antibodies were considered to have good immune function. Univariate and multivariate logistic regression were utilized to study the association between immune function and other demographic, anthropometric and clinical parameters on the likelihood of not being diagnosed with COVID-19. Four models were constructed: Model 1: unadjusted;Model 2: adjusted for age. Model 3: adjusted for age, gender, race, ethnicity, body mass index (BMI). Model 4: adjusted for parameters in model 3 and dialysis vintage (in years), diabetes and congestive heart failure (CHF). RESULTS: 11 870 patients were included in this analysis. 54% patients were male, 33% were Black, 24% of the patients were Hispanic, 69% had diabetes and 22% had CHF. Patients were 61.2 ± 14.4 years old with dialysis vintage of 3.9 ± 3.9 years, BMI of 29.6 ± 9.7 kg/m2 and eKt/V 1.5 ± 0.3. Of these patients, 21% had poor immune function and 79% had good immune function. Results of the logistic regression models are shown in Table 1. In the unadjusted model, poor immune function was associated with an increased likelihood of being diagnosed with COVID-19. In models, 2, 3 and 4 age, vintage and presence of diabetes were all significantly associated with a higher likelihood of being diagnosed with COVID-19. However, poor immune function was not a significant predictor of COVID-19 diagnosis in the adjusted models. CONCLUSION: Patients who have vaccinal or post-HBV antibodies did not have a lower likelihood of COVID-19 compared with patients who were unable to mount an adequate vaccinal or post-HBV antibody response. Response to HBV vaccination or infection may not be adequate to characterize a patient as having good immune response. Other factors that are routinely measured in hemodialysis patients, which may allow us to make inferences about a patient's immune function should be explored.

9.
Cancer Immunology Research ; 10(1 SUPPL), 2022.
Article in English | EMBASE | ID: covidwho-1677458

ABSTRACT

Despite extensive clinical evidence on the efficacy and safety of SARS-CoV-2 vaccines, there remains a paucity of data on their effectiveness in cancer patients who are actively receiving antineoplastic therapeutics. A recent study demonstrated only ∼30% of cancer patients had positive serologic test following 2 doses of FDA-authorized SARS-CoV-2 vaccines, in contrast to ∼80% positivity rate in healthy individuals, regardless of the age. Therefore, furtherinvestigation into novel approaches to boost immune response to SARS-CoV-2 vaccines in cancer patients isrequired. Our previous preclinical and clinical studies have established intratumoral IL-12 plasmid (TAVO)electroporation (EP) induces localized expression of IL-12p70, converting immune-excluded tumors into inflamedimmunogenic lesions, thereby generating objective responses in both treated and untreated, distant tumors. Basedon the enhancement of immunotherapy efficacy by IL-12, we leveraged the flexibility of our DNA plasmid-EPplatform to express SARS-CoV-2 spike protein in addition to IL-12 (CORVax12) as an intratumoral vaccine candidate which we hypothesized could not only drive anti-SARS-CoV-2 immune responses but also generate aproductive anti-tumor response. Naïve mice were vaccinated via intradermal injection of SARS-CoV-2 spike plasmidfollowed immediately by EP with or without plasmid-encoded mIL-12 on days 1 and 21. Longitudinal serum samples were collected to interrogate virus-specific cellular responses as well anti-spike IgG antibody. A surrogate viralneutralization test (sVNT) assessed serum blockade of soluble human ACE2 binding to immobilized SARS-CoV-2spike. Our data demonstrated that intradermally electroporated CORVax12 elicits significantly higher anti-SARS-CoV-2 spike IgG antibodies and neutralization when compared with EP of SARS-CoV-2 spike alone. Next, we askedif improved SARS-CoV-2 immune response may be observed when CORVax12 is incorporated into intratumoral EPin single-tumor bearing mice. CORVax12 robustly inhibited tumor growth, induced high percentages of germinal-center B cells and class switched B cells in tumor draining lymph nodes, and generated high of anti-spike IgG and neutralization antibodies. To further investigate systemic effects of this combination, we continued with contralateraltumor mice models. In both CT26 and B16-F10 tumor models, CORVax12 intratumoral EP induced strong systemicanti-tumor responses similar to IL-12 EP alone while also producing high serum levels of anti-SARS-CoV-2 spikeIgG and neutralization antibodies. Critically, this anti-viral immunity did not limit this IL-12-based intratumoral anti-tumor therapy. In summary, our preclinical data indicates that intratumoral EP of CORVax12 can induce IgGresponses to SARS-CoV-2 spike as well as apparent viral neutralizing activity all while maintaining local and systemic anti-tumor effects expected from TAVO Treatment. This combined intratumoral therapy represents a novelstrategy to address both tumor burden and anti-SARS-CoV-2 immunity in patients with cancer.

10.
Respirology ; 26(SUPPL 3):18-19, 2021.
Article in English | EMBASE | ID: covidwho-1583447

ABSTRACT

Background: In 2020, the coronavirus disease 2019 began spreading widely across the world. We aim to study the biological changes of SARS-CoV-2 infected Vero cells using high-throughput sequencing data, which will be helpful for vaccine development and drug screening. Methods: The data GSE153940 was obtained from the Gene Expression Omnibus database. R software was used to screen out differentially expressed genes and perform Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. The protein-protein interaction network was built by STRING. Cytoscape 3.7.2 was applied for the visualization of the protein-protein interaction network and the identification of the hub genes. GraphPad Prism 8.4.3 was used to perform the statistical analysis to verify the obtained central genes. Results: A total of 3640 differentially expressed genes were obtained. The most significant enrichment items of Gene Ontology in the biological process, cellular component, and molecular function were the regulation of mRNA metabolic process, organelle inner membrane, and cadherin binding respectively. Ten enrichment pathways were identified by the Kyoto Encyclopedia of Genes and Genomes analyses. A protein-protein interaction network with 328 nodes and 498 edges was established. Six hub genes were screened out, among which four genes (MRPS7, DAP3, CHCHD1 and MRPL3) were confirmed to be statistically significant. Conclusions: Our results suggest that mitochondrial activity has a significant role in the process of SARS-CoV-2 infecting Vero E6 cells. Further experimental studies are needed to obtain abundant data to verify the predicted results of the bioinformatics analysis.

11.
European Journal of Integrative Medicine ; 48, 2021.
Article in English | EMBASE | ID: covidwho-1587783

ABSTRACT

Introduction: Chinese patent medicine (CPM) is an indispensable part of traditional Chinese medicine. Coronavirus Disease 2019 (COVID-19) manifests is an acute respiratory infectious disease. This systematic review aimed to evaluate the therapeutic effects and safety of oral CPM for COVID-19. Methods: We included randomized controlled trials (RCTs) that tested oral CPM for the treatment of COVID-19 identified from publications in CNKI, Wanfang, VIP, Web of Science, SinoMed, PubMed, Embase, BioRxiv, MedRxiv and arXiv before November 2nd, 2020. The risk of bias for each trial was assessed using the Cochrane Risk of Bias Tool 2.0. RevMan 5.4 software was used for data analyses. The certainty of the evidence was assessed using the online GRADEpro tool. Results: Seven RCTs including 1079 participants were identified. The overall bias was assessed as “some concerns” for all included trials. Oral CPM investigated were: Lianhua Qingwen capsule/granules (连花清瘟胶囊/颗粒, LHQW), Jinhua Qinggan granules (金花清感颗粒, JHQG), Huoxiang Zhengqidripping pills (藿香正气滴丸, HXZQ), Toujie Quwen granules (透解祛瘟颗粒, TJQW) and Lianhua Qingke granules (连花清咳颗粒, LHQK). Compared with conventional western therapy alone for people with COVID-19: regarding the main outcomes, the results showed that oral CPM combined with conventional western therapy improved cure rate (RR = 1.20, 95% CI 1.04 to 1.38, involving LHQW and TJQW), reduced aggravation rate (RR = 0.50, 95% CI 0.29 to 0.85, involving LHQW, JHQG, LHQK and TJQW);with regard to additional outcomes, the results showed that add-on oral CPM shortened the duration of fever, cough and fatigue, improved the recovery rate of cough and fatigue, and increased the improvement and recovery rate of chest CT manifestations. There were some differences in therapeutic effects among various CPMs for the same COVID-19 outcome. The use of TJQW and LHQG appeared not to increase the risk of adverse events, but JHQG may cause mild diarrhea. Conclusions: Low-certainty or very low-certainty evidence demonstrated that oral CPM may have add-on potential therapeutic effects for patients with non-serious COVID-19. There are some differences in therapeutic effects between different oral CPMs for the same outcome of COVID-19. The use of TJQW and LHQG probably does not increase the risk of adverse events, but JHQG may cause mild diarrhea in patients. The conclusion of this review needs to be further confirmed by well-designed clinical trials with adequate sample sizes. Keywords: Coronavirus Disease 2019;COVID-19;Chinese patent medicine;Chinese herbal medicine;Systematic review;Meta-analysis

12.
International Conference on Embedded Wireless Systems and Networks, EWSN 2021 ; 2021.
Article in English | Scopus | ID: covidwho-1564976

ABSTRACT

COVID-19 coronavirus is spreading all over the world for almost one year. Keeping Social distance has been proven is an efficient policy against the spread of coronavirus. In this paper, we present a system for indoor monitoring. This system not only measures real-time social distance but also records the chain of potential inflection. In real-time social distance measurement, we use stereo cameras to guarantee high accurate measurement and utilize Edge node to ensure real-time requirements. In the chain of potential inflection record, we present an architecture including object tracking and Handshake Chain database, i.e., Chain of potential inflection. To the best of our knowledge, we are the first presenting a system aim to accelerate query for COVID-19. Finally, we offer several on-going work to advance our system. © 2021 the authors.

13.
Hepatology ; 74(SUPPL 1):322A, 2021.
Article in English | EMBASE | ID: covidwho-1508723

ABSTRACT

Background: Dysregulated immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are thought to underlie the progression of coronavirus disease 2019 (COVID-19). We sought to further characterize host antiviral and cytokine gene expression in COVID-19 patients based on illness severity. Methods: In this case-control study, we retrospectively analyzed 46 recovered COVID-19 patients and 24 healthy subjects (no history of COVID-19) recruited from the Second People's Hospital of Fuyang City. Blood samples were collected from each study participant for RNA extraction and PCR. We assessed changes in antiviral gene expression between healthy controls and patients with mild/moderate (MM) and severe/critical (SC) disease. Results: We found that type I interferon signaling (IFNA2, TLR8, IFNA1, IFNAR1, TLR9, IRF7, ISG15, APOBEC3G, and MX1) and genes encoding proinflammatory cytokines (IL12B, IL15, IL6, IL12A and IL1B) and chemokines (CXCL9, CXCL11 and CXCL10) were upregulated in patients with MM and SC disease. Moreover, we found that IFNA1, apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G (APOBEC3G), and Fas-associated protein with death domain (FADD) were significantly downregulated (P < 0.05) in the SC group compared to the MM group. We also observed that microRNA (miR)-155 and miR-130a levels were markedly higher in the MM group compared to the SC group. Conclusion: COVID-19 is associated with the activation of host antiviral genes. Induction of the IFN system appears to be particularly important in controlling SARS-CoV-2 infection, as decreased expression of IFNA1, APOBEC3G and FADD genes in SC patients, relative to MM patients, may be associated with disease progression.

14.
American Journal of Respiratory and Critical Care Medicine ; 203(9):1, 2021.
Article in English | Web of Science | ID: covidwho-1406925
15.
Cmc-Computers Materials & Continua ; 69(3):2827-2843, 2021.
Article in English | Web of Science | ID: covidwho-1389992

ABSTRACT

Coronavirus disease 2019 (COVID-19) has been termed a "Pandemic Disease" that has infected many people and caused many deaths on a nearly unprecedented level. As more people are infected each day, it continues to pose a serious threat to humanity worldwide. As a result, healthcare systems around the world are facing a shortage of medical space such as wards and sickbeds. In most cases, healthy people experience tolerable symptoms if they are infected. However, in other cases, patients may suffer severe symptoms and require treatment in an intensive care unit. Thus, hospitals should select patients who have a high risk of death and treat them first. To solve this problem, a number of models have been developed for mortality prediction. However, they lack interpretability and generalization. To prepare a model that addresses these issues, we proposed a COVID-19 mortality prediction model that could provide new insights. We identified blood factors that could affect the prediction of COVID-19 mortality. In particular, we focused on dependency reduction using partial correlation and mutual information. Next, we used the Class-Attribute Interdependency Maximization (CAIM) algorithm to bin continuous values. Then, we used Jensen Shannon Divergence (JSD) and Bayesian posterior probability to create less redundant and more accurate rules. We provided a ruleset with its own posterior probability as a result. The extracted rules are in the form of "if antecedent then results posterior probability(e )". If the sample matches the extracted rules, then the result is positive. The average AUC Score was 96.77% for the validation dataset and the Fl-score was 92.8% for the test data. Compared to the results of previous studies, it shows good performance in terms of classification performance, generalization, and interpretability.

16.
37th IEEE International Conference on Data Engineering, ICDE 2021 ; 2021-April:936-947, 2021.
Article in English | Scopus | ID: covidwho-1369293

ABSTRACT

Knowledge graph is a way of structuring information in graph form, by representing entities as nodes and relationships between entities as edges. A knowledge graph often consists of large amount of facts in real-world which can be used in supporting many analytical tasks, e.g., exceptional facts discovery and fact check of claims. In this work, we study a core-based top-k frequent pattern discovery problem which is frequently used as a subroutine in analyzing knowledge graphs. The main challenge of the problem is search space of the candidate patterns is exponential to the combinations of the nodes and edges in the knowledge graph.To reduce the search space, we devise a novel computation framework FastPat with a suite of optimizations. First, we devise a meta-index, which can be used to avoid generating invalid candidate patterns. Second, we propose an upper bound of the frequency score (i.e., MNI) of the candidate pattern that prunes unqualified candidates earlier and prioritize the enumeration order of the patterns. Lastly, we design a join-based approach to compute the MNI of candidate pattern efficiently. We conduct extensive experimental studies in real-world datasets to verify the superiority of our proposed method over the baselines. We also demonstrate the utility of the discovered frequent patterns by a case study in COVID-19 knowledge graph. © 2021 IEEE.

17.
Environmental Science and Technology Letters ; 2021.
Article in English | Scopus | ID: covidwho-1279806

ABSTRACT

Airborne transmission of SARS-CoV-2 plays a critical role in spreading COVID-19. To protect public health, we designed and fabricated electrospun nanofibrous air filters that hold promise for applications in personal protective equipment (PPE) and the indoor environment. Due to ultrafine nanofibers (∼300 nm), the electrospun air filters had a much smaller pore size in comparison to the surgical mask and cloth masks (a couple of micrometers versus tens to hundreds of micrometers). A coronavirus strain served as a SARS-CoV-2 surrogate and was used to generate aerosols for filtration efficiency tests, which can better represent SARS-CoV-2 in comparison to other agents used for aerosol generation in previous studies. The electrospun air filters showed excellent performance by capturing up to 99.9% of coronavirus aerosols, which outperformed many commercial face masks. In addition, we observed that the same electrospun air filter or face mask removed NaCl aerosols equivalently or less effectively in comparison to the coronavirus aerosols when both aerosols were generated from the same system. Our work paves a new avenue for advancing air filtration by developing electrospun nanofibrous air filters for controlling SARS-CoV-2 airborne transmission. ©

18.
American Journal of Respiratory and Critical Care Medicine ; 203(9), 2021.
Article in English | EMBASE | ID: covidwho-1277761

ABSTRACT

Introduction: The SARS CoV2 pandemic has produced morbidity and mortality worldwide which depends on age, body mass index, cardiovascular disease and other factors. Of the human coronaviruses, only SARS-CoV2 and HCoV-NL63 bind the ACE2 protein. HCoV-NL63 causes upper respiratory tract infections in children but has also been reported to cause pneumonia and even Kawasaki disease. Hypothesis: HCoV-NL63 produces lung inflammation in mice expressing the human ACE2 protein. Methods: HCoV-NL63 (BEI Resources) was propagated in Caco-2 cells. Cells were harvested and concentrated to produce a working virus stock. Virus cytopathic effect in Vero cells at 48 h infection was determined by TCID50. B6.Cg-Tg(K18-ACE2)2Prlmn mice (Jackson Laboratories) express the human ACE2 protein in epithelial cells under the direction of the keratin 18 promoter. Eight-10 week-old K18-hACE2 or C57BL6/J mice were infected with 50 μ L (100,000 TCID50 units) HCoV-NL63 or sham Caco-2 extract intranasally and euthanized at 2, 4, and 7 days post-treatment. Mouse lungs were assessed for histology, IFN and cytokine mRNAs, ACE2, viral RNA and HCoV-NL63 proteins (nucleoprotein, Nsp3 and Nsp4). Primers designed from HCoV-NL63 sequence (NC-005831.2) were used to measure vRNA by qPCR. Polyclonal antibodies to Nsp3 and Nsp4 were generated (Chen et al, J Virol 2007). Antibodies to human ACE2 (InVitrogen), HCoV-NL63 nucleoprotein (clone 2D5, Eurofins), Nsp3 and Nsp4 were conjugated with AlexaFluor dyes. Results: HCoV-NL63 produced cytopathic effects in Vero cells colocalized with viral nucleoprotein. Virus propagated in K18-hACE2 but not C57BL6/J mice. vRNA levels plateaued 4 days after infection and were detectable 7 days after infection. Lung mRNA expression of IFN-α, IFN-β, IFN-λ, CXCL1 and IL-6 were significantly increased 48 h after infection in HCoV-NL63-treated K18-hACE2 but not C57BL6/J mice (N=3, p<0.05, Kruskal-Wallis test). Sections of mouse lung demonstrated bronchovascular and peribronchial inflammation that were most evident 7 days after infection. Nucleoprotein was found on the apical surface of airway epithelial cells of HCoV-NL63- but not sham-infected K18-hACE2 mice, and Nsp3 and Nsp4 were found in the basal and perinuclear cytoplasm of airway epithelial cells. Conclusion: Human coronavirus NL63 infects K18-ACE2 mice inducing an airway inflammatory response. Viral replication is evidenced by vRNA levels, interferon mRNA expression and production non-structural viral proteins. This model may be used to study HCoV-NL63-induced exacerbation of allergic airways disease;the effect of allergy, obesity and aging on human coronavirus infection, and possible cross-immunity between HCoV-NL63 and other respiratory viruses.

19.
American Journal of Respiratory and Critical Care Medicine ; 203(9), 2021.
Article in English | EMBASE | ID: covidwho-1277239

ABSTRACT

Rationale: Enhancing COPD management should include optimal disease recognition at the primary care level. As effective COPD diagnosis may involve all levels of primary care clinic staff, the CAPTURE validation study included workflow reviews, patient opinion surveys, staff questionnaires, clinician focus groups and case-based vignettes to cohesively form a robust real-world practice assessment of COPD case-finding readiness. We employed this multi-method qualitative sub-aim approach to guide CAPTURE's longitudinal quantitative assessments and to inform strategies for practice implementation of the CAPTURE tool after study completion.Methods: 196 adults without diagnosis of COPD from 82 US practices;and, 114 primary care clinic staff evenly enrolled in the CAPTURE study from 7 US practice-based research networks (PBRNs) that serve rural and urban locales. Sitespecific practice information, clinician questionnaires, and patient responses populated focus group themes. Analyses of clinician and patient responses including frequencies and correlations by clinician level and practice were assessed. 10 practices participated in clinician focus groups that investigated salience, patterning, and contexts of key discourse items. Responses were assigned a priori codes as relevant for CAPTURE implementation planning, COPD diagnosis, CAPTURE intra-office clinical communication, and COPD and CAPTURE education preference, as well as COPD assessment options before and after the COVID-19 pandemic. Results: Patients strongly agreed (>90%) the CAPTURE tool was easy to read and understand, without response difference to questions via verbal versus written administration. Despite lack of COPD staff knowledge reflecting known national primary care education need, clinicians agreed (> 90%) the CAPTURE tool would aid COPD casefinding and aligned with patients (>90%) that CAPTURE could be implemented and completed as part of routine health screening within 5 minutes. Despite most clinicians reporting a lack of reliable on-site pulmonary function capability, physicians, nurses, nurse practitioners, physician assistants, medical assistants uniformly strongly agreed (>90%) that the peak flow testing (PEF) component of CAPTURE could aid respiratory assessment. All practices agreed they'd consider alternate PEF strategies as part of in-person or telehealth assessments if pandemic public health concerns persisted. Conclusions: Thorough qualitative review of CAPTURE in primary care practice demonstrates readiness for this COPD case-finding tool's implementation into US primary care. With CAPTURE operating characteristic validation underway among 5000 patients in practices with wide demographic and geographic variability, this qualitative methodology 1) offered critical in-study information guiding protocol adjustment impacted by unforeseen events (e.g. the COVID crisis);and, 2) clearly outlined COPD diagnosis processes preferred for real-world primary care use. Figure 1.

20.
Chinese Journal of Radiology (China) ; 55(3):245-249, 2021.
Article in Chinese | Scopus | ID: covidwho-1154582
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