A retrospective study of knowledge management for integrated resorts (IRs) crisis preparedness

PurposeThis study aims to propose a systematic knowledge management model to explore the causal links leading to the organizational crisis preparedness (OCP) level of integrated resorts (IRs) during the COVID-19 pandemic based on the intangible capital of organizational climate, dynamic capability, substantive capability and commitment.Design/methodology/approachThe authors use data obtained from IRs in Macau. The Wuli–Shili–Renli (WSR) approach underpins the study. Structural equation modeling following fuzzy-set qualitative comparative analysis (fsQCA) was used for data processing.FindingsThe results showed that organizational climate has an essential role in IRs preparedness for crises and affects their dynamic capacity, substantive capacity and commitment. The fsQCA results revealed that the relationships between conditions with a higher level of dynamic and substantive capability lead to higher OCP scores.Practical implicationsExecutives should develop systemic thinking regarding organization preparedness in IRs for crisis management. A comprehensive understanding of the IRs' business environment and crises is necessary, as they will require different factor constellations to allow the organization to perform well in a crisis. Financial support for employees could ensure their assistance when dealing with such situations. Rapid response teams should be set up for daily operations and marketing implementation of each level of the IRs management systems.Originality/valueThis study contributes to the extant literature on IRs crisis management in the OCP aspect. The authors constructed a systematic composite picture of organization executives' knowledge management through the three layers of intangible capitals in WSR. Moreover, the authors explored causal links of WSR from symmetric and asymmetric perspectives.

On Analysis of Temperature Based Topological Indices of Some Covid-19 Drugs

A variety of graphical invariants have been described and tested, offering lots of applications in the fields of nanochemistry, computational networks and in different scientific research areas. One commonly studied group of invariants is the topological index, which allows to research the chemical, biological, and physical properties of a chemical structure. Topological indexes are numerical quantities that can be used to describe the properties of the molecular graph. In this article, we draw from the analytically closed formulas of certain molecular structures of coronavirus such as Ribavirin, Sofosbuvir and Oseltamivir by calculating temperature based topological indices.

Amplification-Free Detection of SARS-CoV-2 Down to Single Virus Level by Portable Carbon Nanotube Biosensors.

The rapid and sensitive detection of trace-level viruses in a simple and reliable way is of great importance for epidemic prevention and control. Here, a multi-functionalized floating gate carbon nanotube field effect transistor (FG-CNT FET) based biosensor is reported for the single virus level detection of SARS-CoV-2 virus antigen and RNA rapidly with a portable sensing platform. The aptamers functionalized sensors can detect SARS-CoV-2 antigens from unprocessed nasopharyngeal swab samples within 1 min. Meanwhile, enhanced by a multi-probe strategy, the FG-CNT FET-based biosensor can detect the long chain RNA directly without amplification down to single virus level within 1 min. The device, constructed with packaged sensor chips and a portable sensing terminal, can distinguish 10 COVID-19 patients from 10 healthy individuals in clinical tests both by the RNAs and antigens by a combination detection strategy with an combined overall percent agreement (OPA) close to 100%. The results provide a general and simple method to enhance the sensitivity of FET-based biochemical sensors for the detection of nucleic acid molecules and demonstrate that the CNT FG FET biosensor is a versatile and reliable integrated platform for ultrasensitive multibiomarker detection without amplification and has great potential for point-of-care (POC) clinical tests.

Thrombosis and bleeding in COVID-19 patients requiring extracorporeal membrane oxygenation: A systematic review and meta-analysis

Background Extracorporeal membrane oxygenation (ECMO) and COVID-19 significantly impact on coagulation system. A systematic review and meta-analysis were performed to explore the prevalence of thrombotic and bleeding events in COVID-19 patients supported with ECMO, summarize anticoagulation regimens, and guide future research. Methods Cochrane, EMBASE, Scopus, and PubMed were searched for studies examining thrombosis and bleeding in COVID-19 patients requiring ECMO. The primary outcomes were prevalence of different types of hemorrhage and thrombosis. The pooled estimated rates and relative risk (RR) were calculated to summarize the outcomes. Results Twenty-three peer-reviewed studies involving 6,878 subjects were included. For thrombotic events, the prevalence of circuit thrombosis was 21.5% (95% CI: 15.5%–27.6%;1,532 patients);ischemic stroke was 2.6% (95% CI: 1.5%–3.7%;5,926 patients);and pulmonary embolism (PE) was 11.8% (95% CI: 6.8%–16.8%;5,853 patients). For bleeding events, 37.4% of patients experienced major hemorrhage (95% CI: 28.1%–46.8%;1,558 patients) and 9.9% experienced intracranial hemorrhage (ICH) (95% CI: 7.8%–12.1%;6,348 patients). COVID-19 cases on ECMO complicated with more ICH than non-COVID-19 patients on respiratory ECMO [RR=2.23 (95% CI: 1.32–3.75)]. Anticoagulation strategies varied among centers. Conclusions Circuit thrombosis and major bleeding were the most common thrombotic and bleeding events. The incidence of ICH was significantly higher when ECMO was indicated for COVID-19 than for other respiratory diseases. There is no evidence for stronger anticoagulation practice and remains no consistent anticoagulation strategy to reduce the occurrence of thrombosis and bleeding under the double "hit” of COVID-19 and ECMO.

Proactive Contact Tracing.

The COVID-19 pandemic has spurred an unprecedented demand for interventions that can reduce disease spread without excessively restricting daily activity, given negative impacts on mental health and economic outcomes. Digital contact tracing (DCT) apps have emerged as a component of the epidemic management toolkit. Existing DCT apps typically recommend quarantine to all digitally-recorded contacts of test-confirmed cases. Over-reliance on testing may, however, impede the effectiveness of such apps, since by the time cases are confirmed through testing, onward transmissions are likely to have occurred. Furthermore, most cases are infectious over a short period; only a subset of their contacts are likely to become infected. These apps do not fully utilize data sources to base their predictions of transmission risk during an encounter, leading to recommendations of quarantine to many uninfected people and associated slowdowns in economic activity. This phenomenon, commonly termed as "pingdemic," may additionally contribute to reduced compliance to public health measures. In this work, we propose a novel DCT framework, Proactive Contact Tracing (PCT), which uses multiple sources of information (e.g. self-reported symptoms, received messages from contacts) to estimate app users' infectiousness histories and provide behavioral recommendations. PCT methods are by design proactive, predicting spread before it occurs. We present an interpretable instance of this framework, the Rule-based PCT algorithm, designed via a multi-disciplinary collaboration among epidemiologists, computer scientists, and behavior experts. Finally, we develop an agent-based model that allows us to compare different DCT methods and evaluate their performance in negotiating the trade-off between epidemic control and restricting population mobility. Performing extensive sensitivity analysis across user behavior, public health policy, and virological parameters, we compare Rule-based PCT to i) binary contact tracing (BCT), which exclusively relies on test results and recommends a fixed-duration quarantine, and ii) household quarantine (HQ). Our results suggest that both BCT and Rule-based PCT improve upon HQ, however, Rule-based PCT is more efficient at controlling spread of disease than BCT across a range of scenarios. In terms of cost-effectiveness, we show that Rule-based PCT pareto-dominates BCT, as demonstrated by a decrease in Disability Adjusted Life Years, as well as Temporary Productivity Loss. Overall, we find that Rule-based PCT outperforms existing approaches across a varying range of parameters. By leveraging anonymized infectiousness estimates received from digitally-recorded contacts, PCT is able to notify potentially infected users earlier than BCT methods and prevent onward transmissions. Our results suggest that PCT-based applications could be a useful tool in managing future epidemics.

Thrombosis and bleeding in patients with COVID-19 requiring extracorporeal membrane oxygenation: a systematic review and meta-analysis.

Background: Extracorporeal membrane oxygenation (ECMO) and COVID-19 significantly impact the coagulation system. A systematic review and meta-analysis were performed to explore the prevalence of thrombotic and bleeding events in patients with COVID-19 supported with ECMO, summarize anticoagulation regimens, and guide future research. Methods: Cochrane, EMBASE, Scopus, and PubMed were searched for studies examining thrombosis and bleeding in patients with COVID-19 requiring ECMO. The primary outcomes were the prevalences of different types of hemorrhage and thrombosis. The pooled estimated rates and relative risk (RR) were calculated to summarize the outcomes. Results: Twenty-three peer-reviewed studies involving 6878 subjects were included. For thrombotic events, the prevalence of circuit thrombosis was 21.5% (95% CI: 15.5%-27.6%; 1532 patients), that of ischemic stroke was 2.6% (95% CI: 1.5%-3.7%; 5926 patients), and that of pulmonary embolism (PE) was 11.8% (95% CI: 6.8%-16.8%; 5853 patients). For bleeding events, 37.4% of the patients experienced major hemorrhage (95% CI: 28.1%-46.8%; 1558 patients) and 9.9% experienced intracranial hemorrhage (ICH; 95% CI: 7.8%-12.1%; 6348 patients). COVID-19 cases on ECMO were complicated with more ICH than patients without COVID-19 on respiratory ECMO [RR = 2.23 (95% CI: 1.32-3.75)]. Anticoagulation strategies varied among centers. Conclusions: Circuit thrombosis and major bleeding were the most common thrombotic and bleeding events. The incidence of ICH was significantly higher when ECMO was indicated for COVID-19 than for other respiratory diseases. There is no evidence for stronger anticoagulation practice, and remains no consistent anticoagulation strategy to reduce the occurrence of thrombosis and bleeding under the double "hit" of COVID-19 and ECMO.

Aptamers targeting SARS-COV-2: a promising tool to fight against COVID-19.

SARS-CoV-2, the causative agent of COVID-19, remains among the main causes of global mortality. Although antigen/antibody-based immunoassays and neutralizing antibodies targeting SARS-CoV-2 have been successfully developed over the past 2 years, they are often inefficient and unreliable for emerging SARS-CoV-2 variants. Novel approaches against SARS-CoV-2 and its variants are therefore urgently needed. Aptamers have been developed for the detection and inhibition of several different viruses such as HIV, influenza viruses, Middle East respiratory syndrome coronavirus (MERS-CoV), and SARS-CoV. Aptamers targeting SARS-CoV-2 represent a promising tool in the fight against COVID-19, which is of paramount importance for the current and any future pandemics. This review presents recent advances and future trends in the development of aptamer-based approaches for SARS-CoV-2 diagnosis and treatment.

Explore the Approaches to Corporate Social Responsibility Implemented by E-Commerce Platforms in China During the Early Stage of COVID-19: A Mixed-Methods Content Analysis.

OBJECTIVES: The aim of this study was to explore (a) the approaches to corporate social responsibility (CSR) implemented by e-commerce platforms in China during the early stage of coronavirus disease 2019 (ESCOVID-19) and (b) the factors associated with the platforms' choice of these approaches. METHODS: We collected the CSR data from the Internet during ESCOVID-19. Conventional content analysis was used to develop the targeted approaches. Finally, based on the frequency analysis of each approach, rank-based nonparametric testing was conducted to answer objective (b). RESULTS: Three main approaches (ie, donative CSR actions, responsive CSR actions, and strategic CSR actions) and 8 subapproaches were implemented. The strategic approach was the most frequently used approach. The platforms with higher market size implemented more donative and strategic CSR actions than did the platforms with lower market size. Donative CSR actions were significantly implemented in the earlier period, while strategic CSR actions were significantly implemented in the later period. CONCLUSIONS: Our research highlights the importance of e-commerce platforms to help the public survive and identifies that market size and time were associated with the platforms' CSR choice. The design of prevention and control policies should incorporate and support e-commerce platforms and evaluate the factors when confronting future public health crises.

Neutrophil extracellular traps are increased after extracorporeal membrane oxygenation support initiation and present in thrombus: A preclinical study using sheep as an animal model.

BACKGROUND: The balance between thrombosis and hemostasis is a difficult issue during extracorporeal membrane oxygenation (ECMO) support. The pathogenesis leading to thrombotic complications during ECMO support is not well understood. Neutrophil extracellular traps (NETs) were reported to participate in thrombosis and have a key role in inflammation. This study aimed to explore the role of NETs in thrombosis during ECMO support and investigate NETs as a predictive biomarker for thrombotic complications during ECMO assistance. METHODS: Ten ovine models of ECMO support were established. Animals were then randomly divided into 2 groups (5 sheep/group): venoarterial (VA) ECMO group and venovenous (VV) ECMO group. The venous blood samples were collected at different time points. Markers of NETs were detected in plasma, neutrophils, and thrombi from the vessels and membrane. Moreover, circulating NETs levels in 8 adults treated in the intensive care unit (ICU) who received VA-ECMO and 8 healthy controls were detected; patient survival was also recorded. RESULTS: In vivo study showed that neutrophils and NETs markers (dsDNA and citH3) levels were significantly elevated 6 h after ECMO compared to baseline. Isolated neutrophils from fresh blood at 6 h could release more NETs. dsDNA and citH3 levels were significantly higher in the VA mode than in the VV mode. NETs were found in thrombi from the vessel and membrane. Clinical data further revealed that dsDNA, citH3, and nucleosomes were higher in patients who received ECMO than in healthy controls. CONCLUSIONS: These data suggest NETs might be associated with thrombus during ECMO support, especially in the VA mode. These findings provide new insight into preventing thrombotic complications by targeting NETs. Also, NETs may potentially become an early warning biomarker for thrombosis under ECMO assistance.

Epidemiological clustered characteristics of coronavirus disease 2019 (COVID-19) in three phases of transmission in Jilin Province, China.

The current epidemiological status of the new coronary pneumonia epidemic in China is being explored to prevent and control the localized dissemination of aggregated outbreaks. This study analyzed the characteristics of new outbreaks of coronavirus disease 2019 (COVID-19) at three stages of aggregated outbreaks in Jilin Province, China, to provide a reference for the prevention and control of aggregated outbreaks. Case information were collected from all patients in Jilin Province from January 12, 2020 to the present. The epidemic was divided into three stages according to the time of onset. The first stage comprised 97 cases reported from January 12, 2020 to February 19, 2020, during which 17 aggregated outbreaks occurred. The second comprised 43 cases reported from April 25, 2020 and May 23, 2020, involving one aggregated outbreak. The third comprised 435 cases reported on January 10, 2021 and February 9, 2021, involving one aggregated outbreak. The relationship between aggregated and non-aggregated cases in the first phase of the outbreak and the difference between imported and local cases during the aggregated outbreak were assess using statistical analysis, and the differences in the baseline information between the three phases were analyzed. The incubation periods of the three phases were 10 days, 8 days, and 5 days. The number of aggregated epidemic events in Jilin Province tended to increase and then decrease over time. The clustered events in Jilin Province were divided into four categories: household contact (14 times, 51 cases); household contact and public places (one time, three cases); household contact, public places, and gatherings (one time, six cases); and household contact, public places, gatherings, and work (three times, 495 cases). Clustered events occurred mainly between January 22, 2020, and February 4, 2020. Among all cases in the first phase of the outbreak, the method of detection and the time from diagnosis to discharge were longer in aggregated cases than in non-aggregated cases, and that the source of infection and renewal cases were more frequent and more likely to be detected in the outpatient clinics during aggregated outbreaks than the imported cases. The second phase of the epidemic showed significant spatial variability (Moran's I<0, P<0.05). The third stage of the epidemic occurred in a higher proportion of individuals aged 50-90 years and within a shorter incubation period compared with the first two stages. The current focus of prevention and control of the COVID-19 epidemic in Jilin Province is to strictly implement the restrictions on gatherings and to perform timely screening and isolation of close contacts of infectious sources while strengthening the supervision of the inflow of people from outside the region. Simultaneously, more targeted prevention and control measures can be implemented for different age groups and occupations.

Porcine Epidemic Diarrhea Virus nsp13 Protein Downregulates Neonatal Fc Receptor Expression by Causing Promoter Hypermethylation through the NF-κB Signaling Pathway.

Porcine epidemic diarrhea virus (PEDV) is a highly pathogenic porcine enteric coronavirus that causes severe watery diarrhea and even death in piglets. The neonatal Fc receptor (FcRn) is the only transport receptor for IgG. FcRn expressed by intestinal epithelial cells can transport IgG from breast milk to piglets to provide immune protection. Previous studies have shown that viral infection affects FcRn expression. In this study, we showed for the first time, to our knowledge, that FcRn expression can be influenced by methyltransferases. In addition, we found that PEDV inhibited FcRn protein synthesis in porcine small intestinal epithelial cells postinfection. Then, we found that PEDV interfered with the transcription of genes through aberrant methylation modification of the FcRn promoter. DNA methyltransferase 3b (DNMT3b) has been implicated in this process. Using a series of PEDV structural and nonstructural protein (nsp) expression plasmids, we showed that nsp13 plays an important role in this aberrant methylation modification. PEDV nsp13 can affect the NF-κB canonical pathway and promote DNMT3b protein expression by facilitating p65 protein binding to chromatin. PEDV caused aberrant methylation of the FcRn promoter via DNMT3b. The same phenomenon was found in animal experiments with large white piglets. IgG transcytosis demonstrated that PEDV nsp13 can inhibit bidirectional IgG transport by FcRn. In addition, the core region of nsp13 (230-597 aa) is critical for FcRn inhibition. Taken together, to our knowledge, our findings revealed a novel immune escape mechanism of PEDV and shed new light on the design and development of vaccines and drugs.

A novel fuzzy hierarchical fusion attention convolution neural network for medical image super-resolution reconstruction

The clarity of medical images is crucial for doctors to identify and diagnose different diseases. High-resolution images have more detailed information and clearer content than low-resolution images. It is well known that medical images can frequently have some blurred object boundaries, and that traditional deep learning models cannot adequately describe the uncertainty of these blurred boundaries. This paper proposes a new fuzzy metric to characterize the uncertainty of pixels and designs a fuzzy hierarchical fusion attention neural network based on multiscale guided learning. Specifically, a fuzzy neural information-processing block is proposed, which converts an input image into a fuzzy domain using fuzzy membership functions. The uncertainty of the pixels is processed using the proposed fuzzy rules, and then the output of the fuzzy rule layer is fused with the result of the convolution in the neural network. Simultaneously, a multiscale guided-learning dense residual block and pyramidal hierarchical attention module are designed to extract more effective hierarchical image information. Finally, a recurrent memory module with a residual structure is used to process the output features of the hierarchical attention modules. A recursive sub-pixel reconstruction module is used at the tail of the network to reconstruct the images. Compared with existing super-resolution methods using the public COVID-CT dataset, the proposed method demonstrated superior performance in high-resolution medical image reconstruction and reduced the number of parameters and analysis time of the models.

Counter-regulatory renin-angiotensin system in hypertension: Review and update in the era of COVID-19 pandemic.

Cardiovascular disease is the major cause of mortality and disability, with hypertension being the most prevalent risk factor. Excessive activation of the renin-angiotensin system (RAS) under pathological conditions, leading to vascular remodeling and inflammation, is closely related to cardiovascular dysfunction. The counter-regulatory axis of the RAS consists of angiotensin-converting enzyme 2 (ACE2), angiotensin (1-7), angiotensin (1-9), alamandine, proto-oncogene Mas receptor, angiotensin II type-2 receptor and Mas-related G protein-coupled receptor member D. Each of these components has been shown to counteract the effects of the overactivated RAS. In this review, we summarize the latest insights into the complexity and interplay of the counter-regulatory RAS axis in hypertension, highlight the pathophysiological functions of ACE2, a multifunctional molecule linking hypertension and COVID-19, and discuss the function and therapeutic potential of targeting this counter-regulatory RAS axis to prevent and treat hypertension in the context of the current COVID-19 pandemic.

Ischemic stroke and intracranial hemorrhage in extracorporeal membrane oxygenation for COVID-19: A systematic review and meta-analysis.

PURPOSE: Extracorporeal membrane oxygenation (ECMO) is employed to support critically ill COVD-19 patients. The occurrence of ischemic stroke and intracranial hemorrhage (ICH), as well as the implementation of anticoagulation strategies under the dual influence of ECMO and COVID-19 remain unclear. We conducted a systematic review and meta-analysis to describe the ischemic stroke, ICH and overall in-hospital mortality in COVID-19 patients receiving ECMO and summarize the anticoagulation regimens. METHODS: EMBASE, PubMed, Cochrane, and Scopus were searched for studies examining ischemic stroke, ICH, and mortality in COVID-19 patients supported with ECMO. The outcomes were incidences of ischemic stroke, ICH, overall in-hospital mortality and anticoagulation regimens. We calculated the pooled proportions and 95% confidence intervals (CIs) to summarize the results. RESULTS: We analyzed 12 peer-reviewed studies involving 6039 COVID-19 patients. The incidence of ischemic stroke had a pooled estimate of 2.2% (95% CI: 1.2%-3.2%). The pooled prevalence of ICH was 8.0% (95% CI: 6.3%-9.6%). The pooled estimate of overall in-hospital mortality was 40.3% (95% CI: 33.1%-47.5%). The occurrence of ICH was significantly higher in COVID-19 patients supported with ECMO than in other respiratory ECMO [relative risk=1.75 (95% CI: 1.00-3.07)]. Unfractionated heparin was the most commonly used anticoagulant, and anticoagulation monitoring practice varied among centers. CONCLUSIONS: Ischemic stroke and ICH were common under the double "hit" of COVID-19 and ECMO. The prevalence of ICH was significantly higher in COVID-19 patients supported with ECMO than non-COVID-19 patients requiring ECMO. Individualized anticoagulation regimens may be a good choice to balance thrombosis and bleeding. More detailed research and further exploration are needed to clarify the underlying mechanism and clinical management decisions.

Clinical analysis on clinical value of initial chest CT findings in patients with COVID-19

Objective: To assess the clinical value of initial chest CT findings in patients with COVID-19.

A mental health survey among young front-line clinicians in high-risk areas during the COVID-19 sporadic epidemic in China.

Background: The sporadic coronavirus disease (COVID-19) epidemic has placed enormous psychological stress on people, especially clinicians. The objective of this study was to examine depression, anxiety, quality of life (QOL), and related social psychological factors among young front-line clinicians in high-risk areas during the COVID-19 sporadic epidemic in China and to provide a reference for formulating reasonable countermeasures. Methods: In this cross-sectional study, demographic information, COVID-19-related questions, anxiety (Generalized Anxiety Disorder-7, GAD-7), depression (Patient Health Questionnaire-9, PHQ-9), insomnia (Insomnia Severity Index, ISI), stress (Perceived Stress Scale-10, PSS-10), and QOL (World Health Organization Quality of Life-brief version, WHOQOL-BREF) were collected. Binary logistic regression analysis was used to test the relationships between anxiety and/or depression and other related problems. Multiple linear regression analysis was used to test the relationships among factors influencing QOL. Results: A total of 146 young front-line clinicians were included. The prevalence rates of depression, anxiety, and anxiety-depression comorbidity were 37.7% (95% CI = 29.7-45.6%), 26.0% (95% CI = 18.8-33.2%), and 24.0% (95% CI = 17.0-31.0%), respectively. Severe stress (OR = 1.258, 95% CI = 1.098-1.442, P < 0.01) and insomnia (OR = 1.282, 95% CI = 1.135-1.447, P < 0.01) were positively correlated with depression. Severe stress (OR = 1.487, 95% CI = 1.213-1.823, P < 0.01) and insomnia (OR = 1.131, 95% CI = 1.003-1.274, P < 0.05) were positively correlated with anxiety. Severe stress (OR = 1.532, 95% CI = 1.228-1.912, P < 0.01) was positively correlated with anxiety-depression comorbidity. However, insomnia (OR = 1.081, 95% CI = 0.963-1.214, P > 0.05) was not correlated with anxiety-depression comorbidity. The belief that the vaccine will stop the COVID-19 pandemic (OR = 0.099, 95% CI = 0.014-0.715, P < 0.05) was negatively correlated with anxiety and anxiety-depression comorbidity (OR = 0.101, 95% CI = 0.014-0.744, P < 0.05). Severe stress (B = -0.068, 95% CI = -0.129 to -0.007, P < 0.05) and insomnia (B = -0.127, 95% CI = -0.188 to -0.067, P < 0.01) were negatively correlated with QOL. The belief that the vaccine could provide protection (B = 1.442, 95% CI = 0.253-2.631, P < 0.05) was positively correlated with QOL. Conclusions: The prevalence of depression, anxiety, and even anxiety-depression comorbidity was high among young front-line clinicians in high-risk areas during the COVID-19 sporadic epidemic in China. Various biological and psychological factors as well as COVID-19-related factors were associated with mental health issues and QOL. Psychological intervention should evaluate these related factors and formulate measures for these high-risk groups.

Correlation of gut microbiota and metabolic functions with the antibody response to the BBIBP-CorV vaccine.

Increasing evidence indicates that gut microbiota may play a key role in vaccination immunity. Here, we investigate whether the human gut microbiota and metabolic function correlate with the BBIBP-CorV vaccine response. A total of 207 participants who received the BBIBP-CorV vaccine are enrolled. The gut microbiome and metabolic functions are investigated using metagenomic sequencing and metabolomic assays. We find that BBIBP-CorV vaccination is accompanied by altered microbiome composition and functional pathways, and the gut microbiome and its functional profiles correlate with the vaccine response. The levels of short-chain fatty acids (SCFAs) are much higher in the high antibody response group compared to the low response group, and several SCFAs display a positive correlation with the antibody response. Our study highlights that the gut microbiome and its function is associated with the BBIBP-CorV vaccine response, providing evidence for further exploration of microbiome modulation to improve COVID-19 vaccine efficacy.

Dynamic change of COVID-19 lung infection evaluated using co-registration of serial chest CT images.

Purpose: To evaluate the volumetric change of COVID-19 lesions in the lung of patients receiving serial CT imaging for monitoring the evolution of the disease and the response to treatment. Materials and methods: A total of 48 patients, 28 males and 20 females, who were confirmed to have COVID-19 infection and received chest CT examination, were identified. The age range was 21-93 years old, with a mean of 54 ± 18 years. Of them, 33 patients received the first follow-up (F/U) scan, 29 patients received the second F/U scan, and 11 patients received the third F/U scan. The lesion region of interest (ROI) was manually outlined. A two-step registration method, first using the Affine alignment, followed by the non-rigid Demons algorithm, was developed to match the lung areas on the baseline and F/U images. The baseline lesion ROI was mapped to the F/U images using the obtained geometric transformation matrix, and the radiologist outlined the lesion ROI on F/U CT again. Results: The median (interquartile range) lesion volume (cm3) was 30.9 (83.1) at baseline CT exam, 18.3 (43.9) at first F/U, 7.6 (18.9) at second F/U, and 0.6 (19.1) at third F/U, which showed a significant trend of decrease with time. The two-step registration could significantly decrease the mean squared error (MSE) between baseline and F/U images with p < 0.001. The method could match the lung areas and the large vessels inside the lung. When using the mapped baseline ROIs as references, the second-look ROI drawing showed a significantly increased volume, p < 0.05, presumably due to the consideration of all the infected areas at baseline. Conclusion: The results suggest that the registration method can be applied to assist in the evaluation of longitudinal changes of COVID-19 lesions on chest CT.