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1.
The Journal of investigative dermatology ; 141(5):S113-S113, 2021.
Article in English | EuropePMC | ID: covidwho-1823068
2.
Journal of Image and Graphics ; 27(3):722-749, 2022.
Article in Chinese | Scopus | ID: covidwho-1789678

ABSTRACT

Lung disease like corona virus disease 2019(COVID-19) and lung cancer endanger the health of human beings. Early screening and treatment can significantly decrease the mortality of lung diseases. Computed tomography (CT) technology can be an effective information collection method for the diagnosis and treatment of lung diseases. CT-based lung lesion region image segmentation is a key step in lung disease screening. High quality lung lesion region segmentation can effectively improve the level of early stage diagnosis and treatment of lung diseases. However, high-quality lung lesion region segmentation in lung CT images has become a challenging issue in computer-aided diagnosis due to the diversity and complexity of lung diseases. Our research reviews the relevant literature recently. First, it is compared and summarized the pros and cons of traditional segmentation methods of lung CT image based on region and active contour. The region-based method uses the similarity and difference of features to guide image segmentation, mainly including threshold method, region growth method, clustering method and random walk method. The active-contour-based method is to set an initial contour line with decreasing energy. The contour line deforms in the internal energy derived from its own characteristics and the external energy originated from image characteristics. Its movement is in accordance with the principle of minimum energy until the energy function is in minimization and the contour line stops next to the boundary of lung region. The active contour method is divided into parametric active contour method and geometric active contour method in terms of the contour curve analysis. Low segmentation accuracy lung CT image segmentation methods are widely used in the early stage diagnosis. Next, the improved model analysis of lung CT image segmentation network structure is based on convolutional neural networks (CNNs), fully convolutional networks (FCNs), and generative adversarial network (GAN). In respect of the CNN-based deep learning segmentation methods, the segmentation methods of lung and lung lesion region can be divided into two-dimensional and three-dimensional methods in terms of the dimension of convolution kernel, the segmentation methods of lung and lung lesion region can also be divided into two-dimensional and three-dimensional methods based on the dimension of convolution kernel for the FCN-based deep learning segmentation methods. In respect of the U-Net based lung CT image segmentation methods, it can be divided into solo network lung CT image segmentation method and multi network lung CT image segmentation method according to the form of U-Net architecture. Due to the CT image containing COVID-19 infection area is very different from the ordinary lung CT imageand the differentiated segmentation characteristics of the two in the same network, the solo network lung CT image segmentation method can be analyzed that whether the data-set contains COVID-19 or not. The multi-network lung CT image segmentation method can be divided into cascade U-Net and dual path U-Net based on the option of serial mode or parallel mode. For the GAN-based lung CT image segmentation methods, it can be divided into GAN models based on network architecture, generator and other methods according to the ways to improve the different architectures of GAN. Deep-learning-based segmentation method has the advantages of high segmentation accuracy, strong transfer learning ability and high robustness. In particular, the auxiliary diagnosis of COVID-19 cases analysis is significantly qualified based on deep learning. Next, the common datasets and evaluation indexes of lung and lung lesion region segmentation are illustrated, including almost 10 lung CT open datasets, such as national lung screening test(NLST) dataset, computer vision and image analysis international early lung cancer action plan database(VIA/I-ELCAP) dataset, lung image database consortium and image database resource initiative(LIDC-IDRI) dataset and Nederlands-Leuvens Long anker Screenings Onderzoek(NELSON) dataset, and 7 COVID-19 lung CT datasets analysis. It also demonstrates that the related lung CT images datasets is provided based on five large-scale competitions, including TIANCHI dataset, lung nodule analysis 16(LUNA16) dataset, Lung Nodule Database(LNDb) dataset, Kaggle Data Science Bowl 2017(Kaggle DSB) 2017 dataset and Automatic Nodule Detection 2009(ANODE09) dataset, respectively. Our 8 evaluation index is commonly used to evaluate the quality of lung CT image segmentation model, including involved Dice similarity coefficient, Jaccard similarity coefficient, accuracy, precision, false positive rate, false negative rate, sensitivity and specificity, respectively. To increase the number and diversity of training samples, GAN is used to synthesize high-quality adversarial images to expand the dataset. At the end, the prospects, challenges and potentials of CT-based high-precision segmentation strategies are critical reviewed for lung and lung lesion regions. Because the special structure of U-Net can effectively extract target features and restore the information loss derived from down sampling, it does not need a large number of samples for training to achieve high segmentation effect. Therefore, it is necessary to segment lung and lung lesions based on U-Net. The integration of GAN and U-Net is to improve the segmentation accuracy of lung and lung lesion areas. GAN-based network architecture is to extend the dataset for good training quality. The further U-Net application has its priority for qualified segmentation consistently. © 2022, Editorial Office of Journal of Image and Graphics. All right reserved.

3.
Blood ; 138(SUPPL 1):3525, 2021.
Article in English | EMBASE | ID: covidwho-1770434

ABSTRACT

Background - The WINDOW-1 regimen introduced first-line ibrutinib with rituximab (IR) followed by 4 cycles of R-HCVAD for younger mantle cell lymphoma (MCL) patients (pts) demonstrating 90% CR on IR alone and we aimed to improve the CR rate with the addition of venetoclax. We therefore investigated the efficacy and safety of IR and venetoclax (IRV) followed by risk-stratified observation or short course R-HCVAD/MTX-ARA-C as consolidation in previously untreated young patients with mantle cell lymphoma (MCL). Our aim was to use a triplet chemotherapy-free induction to reduce the toxicity, complications and minimize chemotherapy exposure in MCL pts. Methods - We enrolled 50 previously untreated pts in this single institution, single arm, phase II clinical trial - NCT03710772. Pts received IR induction (Part-1) for initial 4 cycles. Pts were restaged at cycle 4 and received IRV for up to eight cycles (Cycle 5 to Cycle 12) starting with ramp up venetoclax dosing in Cycle 5. All pts who achieved CR prior to cycle 12 continued to receive IRV for 4 cycles (maximum 12 cycles) and then moved to part 2. Pts were stratified into three disease risk groups: high, moderate and low risk categories from the baseline data for assignment to R-HCVAD/MTX-ARA-C as consolidation in part 2 (4 cycles, 2 cycles, or no chemotherapy for high, medium and low risk pts respectively). Briefly, low risk pts were those with Ki-67 ≤30%, largest tumor mass <3 cm, low MIPI score and no features of high risk disease (Ki-67 ≥50%, mutations in the TP53, NSD2 or in NOTCH genes, complex karyotype or del17p, MYC positive, or largest tumor diameter >5 cm or blastoid/pleomorphic histology or if they remain in PR after 12 cycles of part 1. Medium risk are pts which did not belong to low or high-risk category. Those who experienced progression on part 1 went to part 2 and get 4 cycles of part 2. Patient were taken off protocol but not off study, if they remained in PR after 4 cycles of chemotherapy, these patients were followed up for time to next treatment and progression free survival on subsequent therapies. After part 2 consolidation, all pts received 2 years of IRV maintenance. The primary objective was to assess CR rates after IRV induction. Adverse events were coded as per CTCAE version 4. Molecular studies are being performed. Results - Among the 50 pts, the median age was 57 years (range - 35-65). There were 20 pts in high-risk group, 20 pts in intermediate-risk group and 10 pts in low-risk group. High Ki-67 (≥30%) in 18/50 (36%) pts. Eighteen (36%) had high and intermediate risk simplified MIPI scores. Six (12%) pts had aggressive MCL (blastoid/pleomorphic). Among the 24 TP53 evaluable pts, eight pts (33%) had TP53 aberrations (mutated and/or TP53 deletion by FISH). Forty-eight pts received IRV. Best response to IRV was 96% and CR of 92%. After part 2, the best ORR remained unaltered, 96% (92% CR and 4% PR). The median number of cycles of triplet IRV to reach best response was 8 cycles (range 2-12). Fifteen pts (30%) did not receive part 2 chemotherapy, two pts (4%) received 1 cycle, 16 pts (32%) 2 cycles and 13 pts (26%) got 4 cycles of chemotherapy. With a median follow up of 24 months, the median PFS and OS were not reached (2 year 92% and 90% respectively). The median PFS and OS was not reached and not significantly different in pts with high and low Ki-67% or with/without TP53 aberrations or among pts with low, medium or high-risk categories. The median PFS and OS was inferior in blastoid/pleomorphic MCL pts compared to classic MCL pts (p=0.01 and 0.03 respectively). Thirteen pts (26%) came off study - 5 for adverse events, 3 for on study deaths, and 2 for patient choice, 2 patients lost to follow up and one for disease progression. Overall, 5 pts died (3 on trial and 2 pts died off study, one due to progressive disease and another due to COVID pneumonia). Grade 3-4 toxicities on part 1 were 10% myelosuppression and 10% each with fatigue, myalgia and rashes and 3% mucositis. One pt developed grade 3 atrial flutter on part 1. None had grade 3-4 bleeding/bruising. Conclusions - Chemotherapy-free induction with IRV induced durable and deep responses in young MCL pts in the frontline setting. WINDOW-2 approach suggests that pts with low risk MCL do not need chemotherapy but further follow up is warranted. This combined modality treatment approach significantly improves outcomes of young MCL pts across all risk groups. Detailed molecular analyses will be reported. (Figure Presented).

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-315413

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) has rapidly spread to more than 200 countries. Thus far, reports regarding multi-center data from throughout gestation in women with COVID-19 and newborn outcomes are scarce. Methods: : We retrospectively reviewed data from 92 pregnant women with COVID-19 (PW-COVID-19) and their 78 newborns from 27 hospitals in 12 regions of Hubei, China. The demographic, epidemiological, clinical, laboratory, and therapeutic data and pregnancy, perinatal, and neonatal outcomes were analyzed. Follow-up was censored until April 7, 2020. Findings: Median maternal age was 31.0 years (IQR 28·0-33·0), with nine patients in the first trimester, five in the second trimester, and 78 in the third trimester. None of the patients died, and most (92·4%) recovered and were discharged. Seventy-five deliveries (including three sets of twins) comprised 66 cesarean sections and nine vaginal deliveries, with 21 preterm and 57 full-term infants. Seventeen live births had radiological findings of pulmonary infection. One newborn tested positive for SARS-CoV-2 nucleic acid, and three newborns were viral antibody-positive: two IgG (+) and IgM (-), and one IgG (+) and IgM (+). The median suspected duration of virus exposure was 7 days (IQR 0 to 27). Interpretation: Compared to the pregnant women with other viral infections, such as SARS, MERS, and Zika virus infection, PW-COVID-19 had similar manifestations and relatively better outcomes. The termination time and delivery mode in PW-COVID-19 should be evaluated based on both the maternal and fetal situations. The possibility of maternal-to-fetal transmission of SARS-CoV-2 requires further investigation.Authors Shujie Liao and Renjie Wang contributed equally to this work.

5.
Embase;
Preprint in English | EMBASE | ID: ppcovidwho-327041

ABSTRACT

The SARS-CoV-2 Omicron with increased fitness is spreading rapidly worldwide. Analysis of cryo-EM structures of the Spike (S) from Omicron reveals amino acid substitutions forging new interactions that stably maintain an “active” conformation for receptor recognition. The relatively more compact domain organization confers improved stability and enhances attachment but compromises the efficiency of viral fusion step. Alterations in local conformation, charge and hydrophobic microenvironments underpin the modulation of the epitopes such that they are not recognized by most NTD- and RBD-antibodies, facilitating viral immune escape. Apart from already existing mutations, we have identified three new immune escape sites: 1) Q493R, 2) G446S and 3) S371L/S373P/S375F that confers greater resistance to five of the six classes of RBD-antibodies. Structure of the Omicron S bound with human ACE2, together with analysis of sequence conservation in ACE2 binding region of 25 sarbecovirus members as well as heatmaps of the immunogenic sites and their corresponding mutational frequencies sheds light on conserved and structurally restrained regions that can be used for the development of broad-spectrum vaccines and therapeutics.

6.
Embase;
Preprint in English | EMBASE | ID: ppcovidwho-326793

ABSTRACT

TMEM16F, a Ca2+22 -activated phospholipid scramblase (CaPLSase), is critical for placental trophoblast syncytialization, HIV infection, and SARS-CoV2-mediated syncytialization. How TMEM16F is activated during cell fusion is unclear. Here, we used trophoblasts as a model for cell fusion and demonstrated that Ca2+influx through Ca2+permeable transient receptor potential vanilloid channel TRPV4 is critical for TMEM16F activation and subsequent human trophoblast fusion. GSK1016790A, a TRPV4 specific agonist, robustly activates TMEM16F in trophoblasts. Patch-clamp electrophysiology demonstrated that TRPV4 and TMEM16F are functionally coupled within Ca 2+microdomains in human trophoblasts. Pharmacological inhibition or gene silencing of TRPV4 hindered TMEM16F activation and subsequent trophoblast syncytialization. Our study uncovers the functional expression of TRPV4 and a physiological activation mechanism of TMEM16F in human trophoblasts, thus providing us with novel strategies to regulate CaPLSase activity as a critical checkpoint of physiologically- and disease-relevant cell fusion events.

7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(2): 103-107, 2022 Feb 06.
Article in Chinese | MEDLINE | ID: covidwho-1600048

ABSTRACT

Influenza is an infectious respiratory disease caused by the influenza viruses. Older people, infants and people with underlying medical conditions could have a higher risk of severe influenza symptoms and complications. The co-infection of Coronavirus Diseases 2019 (COVID-19) with influenza viruses could lead to the complication of prevention, diagnosis, control, treatment, and recovery of COVID-19. Influenza vaccine and COVID-19 vaccine overlapped in target populations, vaccination time, and inoculation units. Although there was insufficient evidence on the immunogenicity and safety of co-administration of influenza vaccine and COVID-19 vaccine, World Health Organization and some countries recommended co-administration of inactivated influenza vaccine and COVID-19 vaccine. This review summarized domestic and international vaccination policies and research progress, and put forward corresponding suggestions in order to provide scientific support for the formulation of vaccination strategy on seasonal influenza vaccine and COVID-19 vaccine.


Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , Aged , COVID-19 Vaccines , China , Humans , Infant , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pandemics/prevention & control , SARS-CoV-2 , Seasons , Vaccination
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(12): 2082-2087, 2021 Dec 10.
Article in Chinese | MEDLINE | ID: covidwho-1600042

ABSTRACT

Objective: To understand the epidemiological characteristics of imported COVID-19 cases in Tianjin, and provide references for risk assessment and control of imported COVID-19 cases. Methods: The information of imported COVID-19 cases were obtained from National Notifiable Disease Report System of China CDC. The data of imported COVID-19 cases reported from Tianjin airport and epidemiological surveys by CDCs at all levels from March 15, 2020 to August 31, 2021 were collected and analyzed by using software Excel 2010, SPSS 25.0 and R. Results: From March 15, 2020 to August 31, 2021, a total of 606 imported cases of COVID-19 were reported in Tianjin, in which 552 cases were finally included in the analysis. The male to female ratio of the cases was 1.8∶1, the age of the cases ranged from 3 to 77 years, and the cases were mainly reported in age group 20-39 years (59.8%). The areas where the imported case sojourned within 14 days included Europe (242 cases, 43.8%), Africa (139 cases, 25.2%), Americas (85 cases, 15.4%) and Asia (86 cases, 15.6%). The proportion of confirmed cases in autumn and winter was relatively high. During the study period, the proportion of infected persons found in custom entry quarantine decreased, and the proportion of persons with personal health declaration and under medical isolation observation increased. The interval between entry and diagnosis of infected persons tended to increase. Conclusion: The proportion of imported COVID-19 cases detected on the first day of entry at Tianjin airport decreased, and the interval to detect the infected persons trended to increase, to which close attention must be paid.


Subject(s)
COVID-19 , Adolescent , Adult , Aged , Child , Child, Preschool , China/epidemiology , Female , Humans , Male , Middle Aged , Quarantine , SARS-CoV-2 , Surveys and Questionnaires , United States , Young Adult
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(12): 2077-2081, 2021 Dec 10.
Article in Chinese | MEDLINE | ID: covidwho-1600024

ABSTRACT

Objective: To compare the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine used for the vaccination in public security officers with different immunization schedules. Methods: From January to February, 2021, 405 public security officers in Taiyuan were randomly divided into 3 groups. Two doses of SARS-CoV-2 inactivated vaccine were injected according to the immunization schedule of 0-14 days, 0-21 days or 0-28 days, respectively. The nucleic acid of SARS-CoV-2 was detected by reverse transcription polymerase chain reaction. The neutralizing antibodies to SARS-CoV-2 were tested by microdose cytopathogenic efficiency assay of live virus. The GMT, seroconversion rate of SARS-CoV-2 neutralizing antibody and safety of the vaccine were analyzed for the 3 groups. Results: The seroconversion rate of SARS-CoV-2 neutralizing antibody was 100% in all the 3 groups. The SARS-CoV-2 neutralizing antibody level of 0-21 day group [166.70 (95%CI: 148.30-185.10)] was similar to that of 0-28 day group [179.50 (95%CI: 156.50-202.60)] (P>0.05), significantly higher than that of 0-14 day group [86.08 (95%CI: 72.36-99.80)] (P<0.001). The incidence rates of adverse reaction in the 3 groups were 1.48% (2/135), 0.74% (1/136) and 1.49% (2/134) respectively (P=0.750), all the adverse reactions were mild. Conclusions: The vaccination of inactivated SARS-CoV-2 vaccine with different immunization schedules in public security officers showed good safety and high seroconversion rate, and the GMTs of SARS-CoV-2 neutralizing antibody in 0-21 day group and 0-28 day group were higher than that in 0-14 day group.


Subject(s)
COVID-19 Vaccines , COVID-19 , Antibodies, Neutralizing , Antibodies, Viral , Humans , Immunization Schedule , SARS-CoV-2 , Vaccines, Inactivated
10.
Zhonghua Yi Xue Za Zhi ; 101(46): 3771-3774, 2021 Dec 14.
Article in Chinese | MEDLINE | ID: covidwho-1572699

ABSTRACT

The lower temperature in autumn-winter provides favorable conditions for the survival and spread of respiratory infectious diseases such as the corona virus disease 2019 (COVID-19) and influenza. It is likely that there will be a co-circulation of respiratory pathogens such as SARS-CoV-2 and influenza. In order to promote the prevention and control of influenza and the application of influenza vaccination during the COVID-19 pandemic in China, we separately discussed the risk of influenza epidemic in the 2021-2022 season, the influenza vaccination policies, and advocate influenza vaccination during the COVID-19 pandemic from the perspective of population medicine. We appeal that COVID-19 vaccination cannot delay the normal delivery of other vaccines in the national immunization programs and non-Expanded Program on Immunization (EPI) vaccines. Promoting influenza vaccination policies and improving immunization service convenience are necessary for increasing influenza vaccine coverage, protecting public health and assisting COVID-19 response.


Subject(s)
COVID-19 , Influenza, Human , COVID-19 Vaccines , Humans , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pandemics , SARS-CoV-2 , Seasons , Vaccination
11.
Zhongguo Huanjing Kexue/China Environmental Science ; 41(10):4703-4711, 2021.
Article in Chinese | Scopus | ID: covidwho-1489586

ABSTRACT

Wastewater-based epidemiology was applied to study the impact of the COVID-19 in 2020 on occurrence and consumption of methamphetamine and ketamine before, during, and after the outbreak in a city of Guangdong province. To estimate the total consumption during the outbreak, mobile data of the city was used to study the dynamics of the population in the towns and districts of the city. The concept of composite population was brought about for the first time and calculated to estimate total drug consumptions of each towns or districts. The population during the outbreak decreased by about 45% relative to before the outbreak. The total consumptions of the two drugs declined by about 75% during the outbreak relative to before the outbreak. However, the decrease to this extent rather implies the persistence of abuse of the two drugs, given the extremely strict control measures. The consumptions of the two drugs were found to decrease by approximately 50% relative to before the outbreak. The consumptions of the drugs rebounded to the level before the outbreak, further demonstrating the persistence of the abuse. © 2021, Editorial Board of China Environmental Science. All right reserved.

12.
Chinese Journal of Applied Clinical Pediatrics ; 36(18):1368-1372, 2021.
Article in Chinese | Scopus | ID: covidwho-1481061

ABSTRACT

Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is still worldwide.As a vulnerable group, severe and dead pediatric cases are also reported.Under this severe epidemic situation, children should be well protected.With the widespread vaccination of SARS-CoV-2 vaccine in adults, the infection rate have decreased.Therefore, SARS-CoV-2 vaccine inoculation for children groups step by step is of great significance to the protection of children and the prevention and control of corona virus disease 2019(COVID-19) as a whole.But the safety of children vaccinated with SARS-CoV-2 vaccine is a main concern of parents.Therefore, in order to ensure the safety of vaccination and the implementation of vaccination work, National Clinical Research Center for Respiratory Diseases, National Center for Children's Health and the Society of Pediatrics, Chinese Medical Association organized experts to interpret the main issue of parents about SARS-CoV-2 vaccine for children, in order to answer the doubts of parents. Copyright © 2021 by the Chinese Medical Association.

13.
Chinese Journal of Applied Clinical Pediatrics ; 36(18):1361-1367, 2021.
Article in Chinese | Scopus | ID: covidwho-1481060

ABSTRACT

At present, severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is still rampant worldwide.As of September 10, 2021, there were about 222 million confirmed cases of corona virus disease 2019(COVID-19)and more than 4.6 million deaths worldwide.With the development of COVID-19 vaccines and the gradual vaccination worldwide, the increasing number of cases in children and unvaccinated young people has drawn attention.According to World Health Organization surveillance data, the proportion of COVID-19 infection cases in children gradually increased, and the proportion of cases in the age groups of under 5 years and 5-14 years increased from 1.0% and 2.5% in January 2020 to 2.0% and 8.7% in July 2021, respectively.At present, billions of adults have been vaccinated with various COVID-19 vaccines worldwide, and their protective effects including reducing infection and transmission, reducing severe disease and hospitalization, and reducing death, as well as high safety have been confirmed.Canada, the United States, Europe and other countries have approved the emergency COVID-19 vaccination in children and adolescents aged 12 to 17 years, and China has also approved the phased vaccination of COVID-19 vaccination in children and adolescents aged 3 to 17 years. For smooth advancement and implementation of COVID-19 vaccination in children, academic institutions, including National Clinical Research Center for Respiratory Diseases, National Center for Children's Health, and The Society of Pediatrics, Chinese Medical Association organized relevant experts to reach this consensus on COVID-19 vaccination in children. Copyright © 2021 by the Chinese Medical Association.

14.
Chinese Journal of New Drugs ; 30(19):1775-1782, 2021.
Article in Chinese | EMBASE | ID: covidwho-1473137

ABSTRACT

Objective: To compare the correlation between the results of SARS-CoV-2 neutralizing antibody colloidal gold test cards prepared by two different principles and the SARS-CoV-2 pseudovirus neutralization experiment, and to evaluate the feasibility of the neutralizing antibody colloidal gold test card for the SARS-CoV-2 neutralizing antibody detection in different populations. Methods: Two kinds of SARS-CoV-2 neutralizing antibody colloidal gold test cards using double antigen sandwich method (manufacturer A) and competitive blocking method (manufacturers B) were used to detect the samples with SARS-CoV-2 neutralizing antibody titers. Detection sensitivity and the correlation between the two methods and the neutralization experiment were compared. The intravenous human immunoglobulin and specific immunoglobulin prepared before the outbreak of COVID-19 epidemic were detected to investigate the specificity of the eligible test card. In order to determine whether there is a hook effect, individual immunized plasma samples of high ELISA titers were tested with series of dilutions and original dilution. Single post-immunized plasma samples were detected with different ELISA titers, the positive rates were determined and the color changes were observed. Single post-immunized plasma samples were screened in the low-dilution area of ELISA according to chromaticity of 120NT50 and 300NT50 on the colorimetric card to prepare pooled plasma. The results were compared with the currently used indirect ELISA method. Results: The detection limits of manufacturers A and B for the first-generation NIBSC international standard 20/136 (anti-SARS-CoV-2 human immunoglobulin international standard) were 0.612 5 and 5 IU•mL-1, respectively. The results of different titers of pooled plasma (both of post-immunization with SARS-CoV-2 vaccine and COVID-19 convalescence plasma) have a good correlation with the neutralizing antibody titer. The post-immunization plasma with high ELISA dilutions (above 10 000) did not show hook effect. The positive rate of individual plasma of different ELISA dilution levels reached 100% when the dilution was above 160, and the uniformity of the chromaticity was higher when the dilution level was above 640. The overall chromaticity became darker as the ELISA dilution increased. The chromaticities of Ppool 120NT50 and Ppool 300NT50 screened according to the colorimetric chart were close to the neutralizing antibody titers. Conclusion: The correlation between the results of the manufacturer A neutralizing antibody test card using the dual antigen sandwich method to detect SARS-CoV-2 neutralizing antibody in convalescent plasma and post-immunization plasma and the titer of the pseudovirus neutralization experiment is better than that of the manufacturer B product using the competitive inhibition method and indirect ELISA. And the color brightness of the detection line is positively correlated with the level of neutralizing antibody, which can be used for preliminary screening of neutralizing antibody in different populations.

15.
Journal of Resources and Ecology ; 12(5):682-692, 2021.
Article in English | Scopus | ID: covidwho-1395223

ABSTRACT

As the COVID-19 pandemic continues to spread, the global tourism industry is facing enormous challenges. There is an urgent need to explore an effective path for tourism to recover and revitalize. With the normalization of the epidemic, tourism destinations will pay more attention to the prevention, warning, and coping strategies of the epidemic, and this focus will also be evident in the study of tourism destination resilience in the post-epidemic period. Some studies on the epidemic and the resilience of tourism are currently underway, but few of them are integrated with research on the resilience of tourism destinations in the post-epidemic period, although no systematic research ideas or methods have been found. Based on resilience theory, this paper summarizes the general research ideas and develops an epidemic resilience model suitable for urban tourism destinations. The present study also proposes a set of research methods based on the index system to analyze the resilience and its spatiotemporal dynamic characteristics of tourism destinations in the post-epidemic period. The methodology can be divided into three stages: Firstly, construct the conceptual model and evaluation system for tourism destination resilience;Secondly, select case sites for empirical analysis, measure the resilience of tourism destinations, and analyze the characteristics of spatiotemporal differences and subsequent factors of influence;And finally, establish an adaptive management mechanism for tourism destinations to use in response to the epidemic and in guiding the formulation of post-epidemic recovery policies. © 2021, Science Press. All right reserved.

16.
Journal of NeuroInterventional Surgery ; 13(SUPPL 1):A88, 2021.
Article in English | EMBASE | ID: covidwho-1394200

ABSTRACT

Introduction Microcatheter exchange increases the risks of intracranial angioplasty and stenting using the Wingspan/Gateway system and may have contributed to the high procedural risks in the SAMMPRIS trial. We present a case series of direct stent deployment through the balloon catheter, simplifying the technique of intracranial angioplasty and stenting using self-expanding stents. Materials and Methods We retrospectively reviewed all patients who underwent stenting for intracranial stenosis with deployment of the Neuroform Atlas stent through the Gateway balloon in our hospital system since this technique was first utilized in October 2020. Procedural success, complication rate, short term clinical and imaging follow-up were assessed. Results Ten Neuroform Atlas stents were deployed through either the Gateway or Emerge balloon catheter in eight patients. The median age was 59 (range 30-75) and 50% were female. All patients had symptomatic severe intracranial stenosis with mean stenosis of 83% (range 70% to 90%). Six patients had recurrent strokes and had failed medical therapy, while two patients presented with acute stroke symptoms and were treated emergently. Mean post-stenting stenosis was 32% (range 0% to 50%). Two procedures were performed under conscious sedation and the rest under general anesthesia. Four stents were placed in the supraclinoid internal carotid artery (ICA), one in the middle cerebral artery M1, two in M2, two in the basilar artery and one in the intracranial vertebral artery. All five patients who underwent short-term follow-up angiograms (mean interval 1.2 months) had further improvement of residual stenosis. There were no ischemic or hemorrhagic periprocedural complications. None of the patients had recurrent TIAs or strokes. One patient died of a COVID-19 infection. One patient had transient neurological deterioration at four months due to profound hypoglycemia. Conclusion Deploying self-expanding stents through an angioplasty balloon catheter is feasible, safe, and can greatly simplify the procedure. The Neuroform Atlas stent is strong enough to prevent immediate recoil of intracranial stenosis after angioplasty.

17.
Journal of International Business Research ; 20(4):1-17, 2021.
Article in English | ProQuest Central | ID: covidwho-1374911

ABSTRACT

Corona Virus Disease 2019 (COVID-19) is an ongoing unprecedented global pandemic crippling world economy and all aspects of human life. Facing shifting COVID epicenters from East to West, many developing and lower-developed countries have been devastated to tackle such public health crisis, especially when endowed with sub-standard health care, unstable and meagerly growing economy, and dearth of resources. Given the pressing need of pandemic control which relies weightily on the 'hardware' of medical treatments and supplies, along with economic remedial plans, this study accentuates the equal importance of the 'software' lying on one 's culture which is deemed to help guiding how people act to collectively reach a COVID relief while achieving societal altruism. Founded on the Hofstede cultural paradigm, this paper offers qualitative investigations on epidemic management of developing and lower-developed countries across East Asia, Latin America, and Africa. It is believed that effective crisis control is most likely resulted from the collaborative culture, reflected in long-term orientation, low individualism, high power distance, low uncertainty avoidance, and low self-indulgence, where an early and comprehensive compliance of public-mandated safety measures is adopted by a country 's citizens, while the risks of failing intervention due to citizens' defiance may prevail in a relatively uncooperative and solitary culture. Facing impending COVID management, policy makers should hence take the pragmatic cultural traits into consideration. This study is original and creative founded on the classification of Hofstede culture.

18.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(8): 1330-1335, 2021 Aug 10.
Article in Chinese | MEDLINE | ID: covidwho-1362625

ABSTRACT

This paper summarizes the basic principles and models of early warning for infectious disease outbreaks, introduces the early warning systems for infectious disease based on different data sources and their applications, and discusses the application potential of big data and their analysing techniques, which have been studied and used in the prevention and control of COVID-19 pandemic, including internet inquiry, social media, mobile positioning, in the early warning of infectious diseases in order to provide reference for the establishment of an intelligent early warning mechanism and platform for infectious diseases based on multi-source big data.


Subject(s)
COVID-19 , Communicable Diseases , Communicable Diseases/epidemiology , Disease Outbreaks/prevention & control , Humans , Pandemics , SARS-CoV-2
19.
Robotics and Computer-Integrated Manufacturing ; 73, 2022.
Article in English | Scopus | ID: covidwho-1327125

ABSTRACT

4D printing technology, as a new generation of Additive Manufacturing methods, enables printed objects to further change their shapes or other properties upon external stimuli. One main category of 4D printing research is 4D printed thermal Shape Memory Polymer (SMP). Its morphing process has large time delay, is nonlinear time variant, and susceptible to unpredictable disturbances. Reaching an arbitrary position with high precision is an active research question. This paper applies the Reinforcement Learning (RL) method to develop an optimal control method to perform closed loop control of the SMP actuation. Precise and prompt shape morphing is achieved compared with previous control methods using a PI controller. The training efforts of RL are further reduced by simplifying the optimal control policy using the structural property of the prior trained results. Customized protective visors against COVID-19 are fabricated using the proposed control method. © 2021 The Author(s)

20.
Zhonghua Yi Xue Za Zhi ; 101(26): 2029-2036, 2021 Jul 13.
Article in Chinese | MEDLINE | ID: covidwho-1317266

ABSTRACT

The disease burden and economic burden of seasonal influenza is substantial in China, and the Coronavirus disease 2019 (COVID-19) pandemic has brought new challenges to the prevention and control of influenza. As a priority group of influenza vaccination, the elderly are at higher risk of influenza-associated severe symptoms and deaths, and they are more price-sensitive vaccine users with better cost-effectiveness of vaccination program. Therefore, a reasonable financing mechanism of influenza vaccination should be designed for the elderly to increase their vaccination rate. This study proposes three financing strategies of influenza vaccination for the elderly in China, trying to explore the distribution of vaccination costs among individuals, central government and local governments under different financing strategies, including the individual-central-local mechanism (strategy 1), the central-local mechanism (strategy 2), and the local payment mechanism (strategy 3). Strategy 1 is feasible and sustainable for most regions in the short term. Strategy 2 is conducive to further increasing the vaccine coverage rate of the elderly. Strategy 3 encourages local fiscal payments to help relieve the financial pressure of the central government. The results revealed a relatively heavy financial burden of influenza vaccination for the elderly, and it is recommended to promote the development of a multiparty co-payment mechanism gradually based on local conditions.


Subject(s)
COVID-19 , Influenza, Human , Aged , China , Cost-Benefit Analysis , Humans , Influenza, Human/prevention & control , SARS-CoV-2 , Vaccination
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