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1.
J Clin Microbiol ; 2021 May 05.
Article in English | MEDLINE | ID: covidwho-1218187

ABSTRACT

While China experienced a peak and decline in coronavirus disease 2019 (COVID-19) cases at the start of 2020, in subsequent months, regional outbreaks have continuously emerged. Resurgences of COVID-19 have also been observed in many other countries. In Guangzhou, China, a small outbreak, involving less than 100 residents, emerged in March and April 2020, and comprehensive and near-real-time genomic surveillance of SARS-CoV-2 was conducted. When the numbers of confirmed cases among overseas travelers increased, public health measures were enhanced by shifting from self-quarantine to central quarantine and SARS-CoV-2 testing for all overseas travelers. In an analysis of 109 imported cases, we found diverse viral variants distributed in the global viral phylogeny, which were frequently shared within households but not among passengers on the same flight. In contrast to the viral diversity of imported cases, local transmission was predominately attributed to two specific variants imported from Africa, including local cases that reported no direct or indirect contact with imported cases. The introduction events of the virus were identified or deduced before the enhanced measures were taken. These results show that the interventions were effective in containing the spread of SARS-CoV-2, and they ruled out the possibility of cryptic transmission of viral variants from the first wave in January and February 2020. Our study provides evidence and emphasizes the importance of controls for overseas travelers in the context of the pandemic and exemplifies how viral genomic data can facilitate COVID-19 surveillance and inform public health mitigation strategies.

2.
International Immunopharmacology ; : 107732, 2021.
Article | WHO COVID | ID: covidwho-1213293

ABSTRACT

Background The benefit of IVIG (Intravenous Immunoglobulin) therapy for COVID-19 remains controversial We performed a meta-analysis to investigate the efficacy of IVIG treatment in patients with COVID-19 Methods We searched articles from Web of Science, PubMed, Embase, the Cochrane Library, MedRxiv between 1 January 2020 and February 17, 2021 We selected randomized clinical trials and observational studies with a control group to assess the efficiency of IVIG in treating patients with COVID-19 Subjects were divided into ‘non-severe’, ‘severe’ and ‘critical’ three subgroups based on the information of the study and the World Health Organization (WHO) definition of severity We pooled the data of mortality and other outcomes using either a fixed-effect model or a random-effects model Results Our meta-analysis retrieved 4 clinical trials and 3 cohort studies including 825 hospitalized patients The severity of COVID-19 is associated with the efficiency of IVIG In critical subgroup, IVIG could reduce the mortality compared with the control group [RR=0 63 (0 45-0 88,I2=25%) But there was no significant difference in the severe or non-severe subgroups Conclusion IVIG has demonstrated clinical efficacy on critical ill patients with COVID-19 There may be a relationship between the efficacy of IVIG and the COVID-19 disease severity Well-designed clinical trials to identify the clinical and biochemical characteristics in COVID-19 patients’ population that could benefit from IVIG are warranted in the future

3.
Cell Research ; 31(5):517-525, 2021.
Article | WHO COVID | ID: covidwho-1210136

ABSTRACT

Neutralizing monoclonal antibodies (nAbs) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represent promising candidates for clinical intervention against coronavirus disease 2019 (COVID-19) We isolated a large number of nAbs from SARS-CoV-2-infected individuals capable of disrupting proper interaction between the receptor binding domain (RBD) of the viral spike (S) protein and the receptor angiotensin converting enzyme 2 (ACE2) However, the structural basis for their potent neutralizing activity remains unclear Here, we report cryo-EM structures of the ten most potent nAbs in their native full-length IgG-form or in both IgG-form and Fab-form bound to the trimeric S protein of SARS-CoV-2 The bivalent binding of the full-length IgG is found to associate with more RBDs in the “up” conformation than the monovalent binding of Fab, perhaps contributing to the enhanced neutralizing activity of IgG and triggering more shedding of the S1 subunit from the S protein Comparison of a large number of nAbs identified common and unique structural features associated with their potent neutralizing activities This work provides a structural basis for further understanding the mechanism of nAbs, especially through revealing the bivalent binding and its correlation with more potent neutralization and the shedding of S1 subunit

5.
Int J Equity Health ; 20(1): 106, 2021 04 26.
Article in English | MEDLINE | ID: covidwho-1204078

ABSTRACT

BACKGROUND: Partial- or full-lockdowns, among other interventions during the COVID-19 pandemic, may disproportionally affect people (their behaviors and health outcomes) with lower socioeconomic status (SES). This study examines income-related health inequalities and their main contributors in China during the pandemic. METHODS: The 2020 China COVID-19 Survey is an anonymous 74-item survey administered via social media in China. A national sample of 10,545 adults in all 31 provinces, municipalities, and autonomous regions in mainland China provided comprehensive data on sociodemographic characteristics, awareness and attitudes towards COVID-19, lifestyle factors, and health outcomes during the lockdown. Of them, 8448 subjects provided data for this analysis. Concentration Index (CI) and Corrected CI (CCI) were used to measure income-related inequalities in mental health and self-reported health (SRH), respectively. Wagstaff-type decomposition analysis was used to identify contributors to health inequalities. RESULTS: Most participants reported their health status as "very good" (39.0%) or "excellent" (42.3%). CCI of SRH and mental health were - 0.09 (p < 0.01) and 0.04 (p < 0.01), respectively, indicating pro-poor inequality in ill SRH and pro-rich inequality in ill mental health. Income was the leading contributor to inequalities in SRH and mental health, accounting for 62.7% (p < 0.01) and 39.0% (p < 0.05) of income-related inequalities, respectively. The COVID-19 related variables, including self-reported family-member COVID-19 infection, job loss, experiences of food and medication shortage, engagement in physical activity, and five different-level pandemic regions of residence, explained substantial inequalities in ill SRH and ill mental health, accounting for 29.7% (p < 0.01) and 20.6% (p < 0.01), respectively. Self-reported family member COVID-19 infection, experiencing food and medication shortage, and engagement in physical activity explain 9.4% (p < 0.01), 2.6% (the summed contributions of experiencing food shortage (0.9%) and medication shortage (1.7%), p < 0.01), and 17.6% (p < 0.01) inequality in SRH, respectively (8.9% (p < 0.01), 24.1% (p < 0.01), and 15.1% (p < 0.01) for mental health). CONCLUSIONS: Per capita household income last year, experiences of food and medication shortage, self-reported family member COVID-19 infection, and physical activity are important contributors to health inequalities, especially mental health in China during the COVID-19 pandemic. Intervention programs should be implemented to support vulnerable groups.


Subject(s)
Health Status Disparities , Income/statistics & numerical data , Adult , China/epidemiology , Female , Humans , Male , Socioeconomic Factors , Surveys and Questionnaires
6.
Front Immunol ; 12: 653344, 2021.
Article in English | MEDLINE | ID: covidwho-1191684

ABSTRACT

Sepsis is a heterogeneous syndrome caused by a dysregulated host response during the process of infection. Neutrophils are involved in the development of sepsis due to their essential role in host defense. COVID-19 is a viral sepsis. Disfunction of neutrophils in sepsis has been described in previous studies, however, little is known about the role of microRNA-let-7b (miR-let-7b), toll-like receptor 4 (TLR4), and nuclear factor kappa B (NF-κB) activity in neutrophils and how they participate in the development of sepsis. In this study, we investigated the regulatory pathway of miR-let-7b/TLR4/NF-κB in neutrophils. We also explored the downstream cytokines released by neutrophils following miR-let-7b treatment and its therapeutic effects in cecal ligation and puncture (CLP)-induced septic mice. Six-to-eight-week-old male C57BL/6 mice underwent CLP following treatment with miR-let-7b agomir. Survival (n=10), changes in liver and lungs histopathology (n=4), circulating neutrophil counts (n=4), the liver-body weight ratio (n=4-7), and the lung wet-to-dry ratio (n=5-6) were recorded. We found that overexpression of miR-let-7b could significantly down-regulate the expression of human-derived neutrophilic TLR4 at a post-transcriptional level, a decreased level of proinflammatory factors including interleukin-6 (IL-6), IL-8, tumor necrosis factor α (TNF-α), and an upregulation of anti-inflammatory factor IL-10 in vitro. After miR-let-7b agomir treatment in vivo, neutrophil recruitment was inhibited and thus the injuries of liver and lungs in CLP-induced septic mice were alleviated (p=0.01 and p=0.04, respectively), less weight loss was reduced, and survival in septic mice was also significantly improved (p=0.013). Our study suggested that miR-let-7b could be a potential target of sepsis.


Subject(s)
/immunology , MicroRNAs/immunology , NF-kappa B/immunology , Neutrophils/immunology , Signal Transduction/immunology , Toll-Like Receptor 4/immunology , /pathology , Humans , Inflammation/immunology , Inflammation/pathology , Neutrophils/pathology
7.
J Zhejiang Univ Sci B ; 22(4): 310-317, 2021 Apr 15.
Article in English | MEDLINE | ID: covidwho-1175474

ABSTRACT

Since December 2019, the novel coronavirus (severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) has spread to many countries around the world, developing into a global pandemic with increasing numbers of deaths reported worldwide. To data, although some vaccines have been developed, there are no ideal drugs to treat novel coronavirus pneumonia (coronavirus disease 2019 (COVID-19)). By examining the structure of the coronavirus and briefly describing its possible pathogenesis based on recent autopsy reports conducted by various teams worldwide, this review analyzes the possible structural and functional changes of the human body upon infection with SARS-CoV-2. We observed that the most prominent pathological changes in COVID-19 patients are diffuse alveolar damage (DAD) of the lungs and microthrombus formation, resulting in an imbalance of the ventilation/perfusion ratio and respiratory failure. Although direct evidence of viral infection can also be found in other organs and tissues, the viral load is relatively small. The conclusion that the injuries of the extra-pulmonary organs are directly caused by the virus needs further investigation.


Subject(s)
/pathology , Lung/pathology , /physiopathology , Human Body , Humans , Immune Evasion , Lung/virology , Viral Load
8.
Int J Qual Health Care ; 33(2)2021 Apr 22.
Article in English | MEDLINE | ID: covidwho-1174913

ABSTRACT

OBJECTIVE: During the COVID-19 pandemic, parents of infants having medical problem face challenges of insufficient medical resources at home. The purpose of this study was to investigate the effect of WeChat-based telehealth services on the preoperative follow-up of infants with congenital heart disease (CHD) during the COVID-19 pandemic. METHODS: This study retrospectively analyzed the medical records of 190 infants with CHD who underwent remote follow-up via WeChat from December 2019 to May 2020 in Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University. In addition, the psychological benefits of WeChat on the parents of these infants were analyzed. RESULTS: In total, 190 infants were involved in this study, including 72 cases of ventricular septal defects, 42 cases of patent ductus arteriosus, 55 cases of atrial septal defects, 3 cases of tetralogy of Fallot, 2 cases of endocardial cushion defects, 12 cases of pulmonary stenosis, 2 cases of total anomalous pulmonary venous connection and 2 cases of aortic arch constriction. During the follow-up period, 48 infants who received surgical indications were hospitalized in time for surgical treatment. It was recommended that 10 infants with respiratory tract infections be treated in local hospitals through the WeChat platform. We provided feeding guidance to 28 infants with dysplasia through the WeChat platform. The psychological evaluation results of parents showed that the median score and range of Self-Rating Depression Scale scores were 42 and 32-58, respectively. Nine parents (4.7%) were clinically depressed, while the majority had mild depression. The median score and range of Self-Rating Anxiety Scale scores were 44 and 31-59, respectively. Twenty parents (10.5%) had clinical anxiety, while the rest had mild anxiety. CONCLUSION: During the COVID-19 pandemic, follow-up management and health services for infants with CHD prior to surgery through the WeChat platform were useful in identifying the state of an infant's condition as well as in identifying and relieving care pressure, anxiety and depression in the parents.


Subject(s)
Heart Defects, Congenital/surgery , Parents/education , Parents/psychology , Telemedicine/methods , Adult , China/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Remote Consultation , Retrospective Studies , Social Media
9.
Acta Neurol Scand ; 2021 Mar 29.
Article in English | MEDLINE | ID: covidwho-1155869

ABSTRACT

The coronavirus disease 2019 caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a pandemic with people infected in almost all countries. The most efficient solution to end this pandemic is a safe and efficient vaccine. Classic platforms are used to develop vaccines including live-attenuated vaccine, inactivated vaccine, protein subunit vaccine, and viral vector. Nucleic acid vaccine uses next-generation platforms for their development. Vaccines are now rushing to the market. Eleven candidates are in advance development. These comprise inactivated vaccines, viral vector vaccine, nucleic acid vaccine, and the protein subunit vaccine platform, which are now quite advanced in trials in various geographic and ethnic populations. The reported severe adverse effects raised the worries about their safety. It becomes critical to know whether these vaccines will cause neurologic disorders like previously recognized vaccine-related demyelinating diseases, fever-induced seizure, and other possible deficits. We reviewed the most promising COVID-2 vaccines with a particular interest in mechanism(s) and adverse effect(s). We exemplify potential neurological problems these vaccines could cause by looking at previous studies. The current evidence indicated a minor risk of the acute neurological disorders after the application. The observation of the long-time effect is still needed.

10.
Medicine (Baltimore) ; 100(8): e24415, 2021 Feb 26.
Article in English | MEDLINE | ID: covidwho-1119145

ABSTRACT

BACKGROUND: The worldwide impact of COVID-19 has reached all spheres of human health. Individuals may also experience unique changes in their sexual behaviors during the COVID-19 self-isolation/social distancing period. Studies in many countries have assess the effects of the pandemic on sexual behavior, or quality of sexual life. However, no systematic review has comprehensively explored the association between COVID-19 and the sexual behaviors of young women and men to date. This systematic review and meta-analysis protocol aims to ascertain the association between COVID-19 and sexual behaviors of young women and men that may get targeted interventions to improve health and well-being of young people's sexual health. METHODS: This systematic review and meta-analysis will be reported following the PRISMA guidelines. Observational designs (including cross-sectional, case-control, and cohort) will be eligible. Studies eligible for inclusion must contain participants aged 15 to 45 in any country affected by the pandemic of COVID-19. The search will be conducted in the following databases, including PubMed, Cochrane Library, EMBASE, EBSCO, Ovid, WHO COVID-19 database, China National Knowledge Internet (CNKI), WanFang Data, Chinese Scientific and Technological Journal Database (VIP), and Chinese Biomedical Databases (CBM). A pre-designed search strategy of medical subject heading (MeSH) terms and free words for the concepts "COVID-19" and "sexual behaviors" will be used. Two authors will independently complete literature screening, data extraction, and risk of bias assessment. Disagreements will be resolved by consensus with a third reviewer. The reviewer will follow the PECOS steps (population, exposure, comparator, outcomes, and study design) to obtain eligible extraction items. The risk of bias and quality of included studies will be assessed using RevMan 5.3. We will assess heterogeneity according to the I2 statistics. If there is substantial heterogeneity in the included trials, subgroup analysis will be carried out to seek the potential causes. ETHICS AND DISSEMINATION: It is not necessary to obtain ethical approval as we will use data from published articles. The findings of this systematic review will be published in a peer- reviewed journal. PROSPERO REGISTRATION NUMBER: PROSPERO 2020: CRD42020190867.


Subject(s)
/epidemiology , Adolescent , Adult , China/epidemiology , Humans , Middle Aged , Observational Studies as Topic , Pandemics , Research Design , Sexual Behavior , Young Adult
11.
Environ Res ; 196: 110927, 2021 05.
Article in English | MEDLINE | ID: covidwho-1116590

ABSTRACT

Clean air is a fundamental necessity for human health and well-being. Anthropogenic emissions that are harmful to human health have been reduced substantially under COVID-19 lockdown. Satellite remote sensing for air pollution assessments can be highly effective in public health research because of the possibility of estimating air pollution levels over large scales. In this study, we utilized both satellite and surface measurements to estimate air pollution levels in 20 cities across the world. Google Earth Engine (GEE) and Sentinel-5 Precursor TROPOspheric Monitoring Instrument (TROPOMI) application were used for both spatial and time-series assessment of tropospheric Nitrogen Dioxide (NO2) and Carbon Monoxide (CO) statuses during the study period (1 February to May 11, 2019 and the corresponding period in 2020). We also measured Population-Weighted Average Concentration (PWAC) of particulate matter (PM2.5 and PM10) and NO2 using gridded population data and in-situ air pollution estimates. We estimated the economic benefit of reduced anthropogenic emissions using two valuation approaches: (1) the median externality value coefficient approach, applied for satellite data, and (2) the public health burden approach, applied for in-situ data. Satellite data have shown that ~28 tons (sum of 20 cities) of NO2 and ~184 tons (sum of 20 cities) of CO have been reduced during the study period. PM2.5, PM10, and NO2 are reduced by ~37 (µg/m3), 62 (µg/m3), and 145 (µg/m3), respectively. A total of ~1310, ~401, and ~430 premature cause-specific deaths were estimated to be avoided with the reduction of NO2, PM2.5, and PM10. The total economic benefits (Billion US$) (sum of 20 cities) of the avoided mortality are measured as ~10, ~3.1, and ~3.3 for NO2, PM2.5, and PM10, respectively. In many cases, ground monitored data was found inadequate for detailed spatial assessment. This problem can be better addressed by incorporating satellite data into the evaluation if proper quality assurance is achieved, and the data processing burden can be alleviated or even removed. Both satellite and ground-based estimates suggest the positive effect of the limited human interference on the natural environments. Further research in this direction is needed to explore this synergistic association more explicitly.

12.
BMJ Open ; 11(2): e045524, 2021 02 25.
Article in English | MEDLINE | ID: covidwho-1105501

ABSTRACT

INTRODUCTION: The increased social and economic burden caused by the novel COVID-19 outbreak is gradually becoming a worrisome issue for the health sector. The novel coronavirus invades the target cell by binding to ACE2, which is widely expressed in the ovaries, uterus, vagina and placenta. Significantly, the SARS-CoV-2 is said to interrupt female fertility through regulating ACE2. Thus, it is essential to investigate if the novel COVID-19 hampers female fertility, given that there is no systematic and comprehensive evidence on the association of COVID-19 with female fertility. METHODS AND ANALYSIS: We will systematically search cohort studies, cross-sectional studies, case-control studies and self-controlled case series designs in the following databases: Web of Science, PubMed, EMBASE, Cochrane Library, Ovid, EBSCO, WHO COVID-19 Database, Chinese Biomedical Databases, China National Knowledge Internet, VIP and WanFang Database. Medical Subject Headings and free-text terms for "COVID-19" AND "female" AND "fertility" will be performed. Eligibility criteria are as follows: population (female patients aged 13-49 years); exposure (infection with SARS-CoV-2); comparison (population without SARS-CoV-2 infections or latent SARS-CoV-2 infections); and outcome (female fertility, such as ovarian reserve function, uterine receptivity, oviducts status and menstruation status). Article screening and data extraction will be undertaken independently by two reviewers, and discrepancies will be resolved through discussion. We will use the I2 statistics to assess the heterogeneity and perform a meta-analysis when sufficiently homogeneous studies are provided. Otherwise, a narrative synthesis will be performed. We will explore the potential sources of heterogeneity using subgroup analyses and meta-regression. ETHICS AND DISSEMINATION: Formal ethical approval is not required, and findings will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42020189856.


Subject(s)
/physiopathology , Fertility , Research Design , Adolescent , Adult , China , Female , Humans , Meta-Analysis as Topic , Middle Aged , Pregnancy , Systematic Reviews as Topic , Young Adult
13.
Cell Host Microbe ; 29(4): 551-563.e5, 2021 04 14.
Article in English | MEDLINE | ID: covidwho-1101147

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is characterized by a burst in the upper respiratory portal for high transmissibility. To determine human neutralizing antibodies (HuNAbs) for entry protection, we tested three potent HuNAbs (IC50 range, 0.0007-0.35 µg/mL) against live SARS-CoV-2 infection in the golden Syrian hamster model. These HuNAbs inhibit SARS-CoV-2 infection by competing with human angiotensin converting enzyme-2 for binding to the viral receptor binding domain (RBD). Prophylactic intraperitoneal or intranasal injection of individual HuNAb or DNA vaccination significantly reduces infection in the lungs but not in the nasal turbinates of hamsters intranasally challenged with SARS-CoV-2. Although postchallenge HuNAb therapy suppresses viral loads and lung damage, robust infection is observed in nasal turbinates treated within 1-3 days. Our findings demonstrate that systemic HuNAb suppresses SARS-CoV-2 replication and injury in lungs; however, robust viral infection in nasal turbinate may outcompete the antibody with significant implications to subprotection, reinfection, and vaccine.


Subject(s)
Antibodies, Neutralizing/therapeutic use , Antibodies, Viral/therapeutic use , /immunology , Turbinates/virology , /physiology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , /virology , Cricetinae , Female , HEK293 Cells , Humans , Male , Mesocricetus , Viral Load
14.
Nurs Outlook ; 2020 Jul 19.
Article in English | MEDLINE | ID: covidwho-1065514

ABSTRACT

BACKGROUND: During an epidemic of a novel infectious disease, frontline nurses suffer from unprecedented psychological stress. This study aimed to assess the immediate psychological impact on frontline nurses in China. METHODS: A multicenter, cross-sectional survey of frontline nurses was conducted via online questionnaires. Symptoms of depression, anxiety, somatic disorders, and suicidal ideation were evaluated. Demographic, stress, and support variables were entered into logistic regression analysis to identify the impact factors. FINDINGS: Of the 4,692 nurses who completed the survey, 9.4% (n = 442) were considered to have depressive symptoms, 8.1% (n = 379) represented anxiety, and 42.7% (n = 2,005) had somatic symptom. About 6.5% (n = 306) respondents had suicidal ideation. DISCUSSION: The study showed that the overall mental health of frontline nurses was generally poor during COVID-19 outbreak, and several impact factors associated with nurses' psychological health were identified. Further research is needed to ascertain whether training and support strategies are indeed able to mitigate psychological morbidities.

15.
Sci Rep ; 11(1): 3187, 2021 02 04.
Article in English | MEDLINE | ID: covidwho-1065963

ABSTRACT

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a novel coronavirus causing the COVID-19 pandemic in 2020. High adaptive plasticity on the spike protein of SASR-CoV-2 enables it to transmit across different host species. In the present study, we collected 2092 high-quality genome sequences of SARS-CoV-2 from 160 regions in over 50 countries and reconstructed their phylogeny. We also analyzed the polymorphic interaction between spike protein and human ACE2 (hACE2). Phylogenetic analysis of SARS-CoV-2 suggests that SARS-CoV-2 is probably originated from a recombination event on the spike protein between a bat coronavirus and a pangolin coronavirus that endows it humans infectivity. Compared with other regions in the S gene of SARS-CoV-2, the direct-binding sites of the receptor-binding domain (RBD) is more conserved. We focused on 3,860 amino acid mutations in spike protein RBD (T333-C525) of SARS-CoV-2 and simulated their differential stability and binding affinity to hACE2 (S19-D615). The results indicate no preference for SARS-CoV-2 infectivity on people of different ethnic groups. The variants in the spike protein of SARS-CoV-2 may also be a good indicator demonstrating the transmission route of SARS-CoV-2 from its natural reservoir to human hosts.


Subject(s)
/genetics , Spike Glycoprotein, Coronavirus/genetics , Animals , Binding Sites , Humans , Mutation , Polymorphism, Genetic , Protein Binding , /genetics
16.
Nat Hazards (Dordr) ; : 1-18, 2021 Jan 15.
Article in English | MEDLINE | ID: covidwho-1064564

ABSTRACT

This study conducts an analysis on topics of the most diffused tweets and retweeting dynamics of crisis information amid Covid-19 to provide insights into how Twitter is used by the public and how crisis information is diffused on Twitter amid this pandemic. Results show that Twitter is first and foremost used as a news seeking and sharing platform with more than 70 % of the most diffused tweets being related to news and comments on crisis updates. As for the retweeting dynamics, our results show an almost immediate response from Twitter users, with some first retweets occurring as quickly as within 2 s and the vast majority ( 90 % ) of them done within 10 min. Nearly 86 % of the retweeting processes could have 75 % of their retweets finished within 24 h, indicating a 1-day information value of tweets. Distribution of retweeting behaviors could be modeled by Power law, Weibull, and Log normal in this study, but still there are 20 % original tweets whose retweeting distributions left unexplained. Results of retweeting community analysis show that following retweeters contribute to nearly 50 % of the retweets. In addition, the retweeting contribution of verified Twitter users is significantly ( P < 0.05 ) different from that of unverified users. A similar significant ( P < 0.05 ) difference is also found in their rates of verified retweeters, and it has been shown that verified Twitter users enjoy seven times as high value as that of unverified users. In other words, users with the same verification status are more likely to get together to diffuse crisis information.

17.
Jpn J Infect Dis ; 2020 Aug 01.
Article in English | MEDLINE | ID: covidwho-1045277

ABSTRACT

We report a hospitalized patient with COVID-19 whose fecal samples turned negative 22 days later than the respiratory samples. It highlights that the duration of virus release from patients is longer than previously expected. Current clinical examinations for treatment and discharge standard are limited to respiratory samples. However, we believe that nucleic acid testing of both respiratory and fecal samples is necessary for discharged patients. Further studies are needed to confirm the potential for fecal-oral transmission or fecal-respiratory transmission via aerosols.

18.
JAMA Pediatr ; 174(12): 1218, 2020 Dec 01.
Article in English | MEDLINE | ID: covidwho-1017872
19.
Nat Commun ; 12(1): 250, 2021 01 11.
Article in English | MEDLINE | ID: covidwho-1019817

ABSTRACT

Understanding the mechanism for antibody neutralization of SARS-CoV-2 is critical for the development of effective therapeutics and vaccines. We recently isolated a large number of monoclonal antibodies from SARS-CoV-2 infected individuals. Here we select the top three most potent yet variable neutralizing antibodies for in-depth structural and functional analyses. Crystal structural comparisons reveal differences in the angles of approach to the receptor binding domain (RBD), the size of the buried surface areas, and the key binding residues on the RBD of the viral spike glycoprotein. One antibody, P2C-1F11, most closely mimics binding of receptor ACE2, displays the most potent neutralizing activity in vitro and conferred strong protection against SARS-CoV-2 infection in Ad5-hACE2-sensitized mice. It also occupies the largest binding surface and demonstrates the highest binding affinity to RBD. More interestingly, P2C-1F11 triggers rapid and extensive shedding of S1 from the cell-surface expressed spike glycoprotein, with only minimal such effect by the remaining two antibodies. These results offer a structural and functional basis for potent neutralization via disruption of the very first and critical steps for SARS-CoV-2 cell entry.


Subject(s)
/chemistry , Antibodies, Monoclonal/chemistry , Antibodies, Neutralizing/immunology , /immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , Antibodies, Viral/immunology , Binding Sites , /virology , Disease Models, Animal , Epitopes , HEK293 Cells , Humans , Mice , Mice, Inbred BALB C , Models, Molecular , Protein Binding , Protein Conformation , Receptors, Virus/immunology , Receptors, Virus/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization
20.
Braz J Cardiovasc Surg ; 2020 Dec 23.
Article in English | MEDLINE | ID: covidwho-1000762

ABSTRACT

INTRODUCTION: To investigate the effect of WeChat-based telehealth services on the postoperative follow-up of children who underwent congenital heart surgery during the COVID-19 epidemic. METHODS: This study retrospectively analyzed the clinical and family data of 108 children who underwent congenital heart surgery and underwent remote follow-up via the WeChat platform from December 2019 to March 2020 in our hospital. RESULTS: During the follow-up period, the WeChat platform was used to refer 8 children with respiratory infection symptoms to local hospitals for treatment. Two children with poor incision healing were healed after we used the WeChat platform to guide the parents in dressing the wounds on a regular basis at home. Nutritional guidance was given via the WeChat platform to 13 patients with poor growth and development. The psychological evaluation results of the parents showed that the median (range) SDS score was 43 (34-59), and 7 parents (6.5%) were classified as depressed; the median (range) SAS score was 41 (32-58), and 12 parents (11.1%) were classified as having mild anxiety. CONCLUSION: The use of WeChat-based telehealth services was effective for the remote postoperative follow-up of children who underwent congenital cardiac surgery during the COVID-19 epidemic. Providing WeChat-based telehealth services can reduce the amount of travel required for these children and their families, which is helpful for controlling and preventing the spread of COVID-19.

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