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2.
Managerial Auditing Journal ; 37(3):380-405, 2022.
Article in English | ProQuest Central | ID: covidwho-1691687

ABSTRACT

PurposeThis study aims to examine the characteristics of financial analysts’ earnings forecasts after COVID-19 outbroke in the USA. Specifically, the authors examine how financial analysts tradeoff between accuracy and responsiveness under investors’ heightened information demand when there is market-wide uncertainty. In addition, the authors investigate how COVID-19 may affect analysts’ cognitive bias.Design/methodology/approachThe research uses a sample of US-listed firms from March 2019 to February 2021, the period surrounding the COVID-19 outbreak in the USA.FindingsThe empirical analyses reveal that analysts issue timelier, more frequent, but less accurate forecasts after the COVID-19 outbreak, indicating that analysts become more responsive to investors’ intensified demand for information during the pandemic. Yet, the high uncertainty caused by COVID-19 increases forecasting difficulty. There is no systematic difference regarding the forecast accuracy between high- and low-ability analysts. Meanwhile, high-quality audit can improve forecast accuracy. Contrary to prior findings that analysts tend to underreact to bad news, the empirical evidence suggests that analysts, shaped by the salience bias, overestimate the negative impact of the pandemic. Analysts first issue pessimistic forecasts at the start of the outbreak and then revise forecasts upward steadily as the fiscal year-end approaches.Originality/valueThe study contributes to the literature by adding novel evidence on how COVID-19-induced uncertainty affects analyst forecast characteristics. It also provides additional evidence on how high-quality audit is associated with improved analyst forecast accuracy even under heightened uncertainty of COVID-19.

3.
Arthritis Res Ther ; 24(1): 6, 2022 01 03.
Article in English | MEDLINE | ID: covidwho-1590005

ABSTRACT

BACKGROUND: Hydroxychloroquine (HCQ) has been recommended as a basic treatment for lupus nephritis (LN) during this decade based on its ability to improve LN-related renal immune-mediated inflammatory lesions. As a classical lysosomal inhibitor, HCQ may inhibit lysosomal degradation and disrupt protective autophagy in proximal tubular epithelial cells (PTECs). Therefore, the final renal effects of HCQ on LN need to be clarified. METHOD: HCQ was administered on spontaneous female MRL/lpr LN mice with severe proteinuria daily for 4 weeks. Moreover, the MRL/lpr mice with proteinuric LN were subjected to cisplatin-induced or unilateral ischemia/reperfusion (I/R)-induced acute kidney injury (AKI) after 2 weeks of HCQ preadministration. RESULTS: As expected, HCQ treatment increased the survival ratio and downregulated the levels of serum creatinine in the mice with LN, ameliorated renal lesions, and inhibited renal interstitial inflammation. Unexpectedly, HCQ preadministration significantly increased susceptibility to and delayed the recovery of AKI complicated by LN, as demonstrated by an increase in PTEC apoptosis and expression of the tubular injury marker KIM-1 as well as the retardation of PTEC replenishment. HCQ preadministration suppressed the proliferation of PTECs by arresting cells in G1/S phase and upregulated the expression of cell cycle inhibitors. Furthermore, HCQ preadministration disrupted the PTEC autophagy-lysosomal pathway and accelerated PTEC senescence. CONCLUSION: HCQ treatment may increase susceptibility and delay the recovery of AKI complicated by LN despite its ability to improve LN-related renal immune-mediated inflammatory lesions. The probable mechanism involves accelerated apoptosis and inhibited proliferation of PTECs via autophagy-lysosomal pathway disruption and senescence promotion.


Subject(s)
Acute Kidney Injury , Lupus Nephritis , Acute Kidney Injury/chemically induced , Animals , Female , Hydroxychloroquine/pharmacology , Kidney/pathology , Mice , Mice, Inbred MRL lpr
4.
J Cardiovasc Transl Res ; 15(1): 38-48, 2022 02.
Article in English | MEDLINE | ID: covidwho-1594479

ABSTRACT

Angiotensin-converting enzyme 2 (ACE2) is required for the cellular entry of the severe acute respiratory syndrome coronavirus 2. ACE2, via the Ang-(1-7)-Mas-R axis, is part of the antihypertensive and cardioprotective effects of the renin-angiotensin system. We studied hospitalized COVID-19 patients with hypertension and hypertensive human(h) ACE2 transgenic mice to determine the outcome of COVID-19 with or without AT1 receptor (AT1R) blocker treatment. The severity of the illness and the levels of serum cardiac biomarkers (CK, CK-BM, cTnI), as well as the inflammation markers (IL-1, IL-6, CRP), were lesser in hypertensive COVID-19 patients treated with AT1R blockers than those treated with other antihypertensive drugs. Hypertensive hACE2 transgenic mice, pretreated with AT1R blocker, had increased ACE2 expression and SARS-CoV-2 in the kidney and heart, 1 day post-infection. We conclude that those hypertensive patients treated with AT1R blocker may be at higher risk for SARS-CoV-2 infection. However, AT1R blockers had no effect on the severity of the illness but instead may have protected COVID-19 patients from heart injury, via the ACE2-angiotensin1-7-Mas receptor axis.


Subject(s)
COVID-19 , Hypertension , Animals , Humans , Hypertension/complications , Hypertension/drug therapy , Inpatients , Mice , Mice, Transgenic , Renin-Angiotensin System , SARS-CoV-2 , Virulence
5.
Signal Transduct Target Ther ; 6(1): 337, 2021 09 06.
Article in English | MEDLINE | ID: covidwho-1402050

ABSTRACT

SARS-CoV-2 has been reported to show a capacity for invading the brains of humans and model animals. However, it remains unclear whether and how SARS-CoV-2 crosses the blood-brain barrier (BBB). Herein, SARS-CoV-2 RNA was occasionally detected in the vascular wall and perivascular space, as well as in brain microvascular endothelial cells (BMECs) in the infected K18-hACE2 transgenic mice. Moreover, the permeability of the infected vessel was increased. Furthermore, disintegrity of BBB was discovered in the infected hamsters by administration of Evans blue. Interestingly, the expression of claudin5, ZO-1, occludin and the ultrastructure of tight junctions (TJs) showed unchanged, whereas, the basement membrane was disrupted in the infected animals. Using an in vitro BBB model that comprises primary BMECs with astrocytes, SARS-CoV-2 was found to infect and cross through the BMECs. Consistent with in vivo experiments, the expression of MMP9 was increased and collagen IV was decreased while the markers for TJs were not altered in the SARS-CoV-2-infected BMECs. Besides, inflammatory responses including vasculitis, glial activation, and upregulated inflammatory factors occurred after SARS-CoV-2 infection. Overall, our results provide evidence supporting that SARS-CoV-2 can cross the BBB in a transcellular pathway accompanied with basement membrane disrupted without obvious alteration of TJs.


Subject(s)
Basement Membrane/metabolism , Blood-Brain Barrier/metabolism , COVID-19/metabolism , SARS-CoV-2/metabolism , Tight Junctions/metabolism , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , Basement Membrane/pathology , Basement Membrane/virology , Blood-Brain Barrier/pathology , Blood-Brain Barrier/virology , COVID-19/genetics , COVID-19/pathology , Chlorocebus aethiops , Disease Models, Animal , Humans , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , Mice , Mice, Transgenic , SARS-CoV-2/genetics , Tight Junctions/genetics , Tight Junctions/pathology , Tight Junctions/virology , Vero Cells
6.
J Med Virol ; 93(9): 5376-5389, 2021 09.
Article in English | MEDLINE | ID: covidwho-1363676

ABSTRACT

The suppression of types I and III interferon (IFN) responses by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contributes to the pathogenesis of coronavirus disease 2019 (COVID-19). The strategy used by SARS-CoV-2 to evade antiviral immunity needs further investigation. Here, we reported that SARS-CoV-2 ORF9b inhibited types I and III IFN production by targeting multiple molecules of innate antiviral signaling pathways. SARS-CoV-2 ORF9b impaired the induction of types I and III IFNs by Sendai virus and poly (I:C). SARS-CoV-2 ORF9b inhibited the activation of types I and III IFNs induced by the components of cytosolic dsRNA-sensing pathways of RIG-I/MDA5-MAVS signaling, including RIG-I, MDA-5, MAVS, TBK1, and IKKε, rather than IRF3-5D, which is the active form of IRF3. SARS-CoV-2 ORF9b also suppressed the induction of types I and III IFNs by TRIF and STING, which are the adaptor protein of the endosome RNA-sensing pathway of TLR3-TRIF signaling and the adaptor protein of the cytosolic DNA-sensing pathway of cGAS-STING signaling, respectively. A mechanistic analysis revealed that the SARS-CoV-2 ORF9b protein interacted with RIG-I, MDA-5, MAVS, TRIF, STING, and TBK1 and impeded the phosphorylation and nuclear translocation of IRF3. In addition, SARS-CoV-2 ORF9b facilitated the replication of the vesicular stomatitis virus. Therefore, the results showed that SARS-CoV-2 ORF9b negatively regulates antiviral immunity and thus facilitates viral replication. This study contributes to our understanding of the molecular mechanism through which SARS-CoV-2 impairs antiviral immunity and provides an essential clue to the pathogenesis of COVID-19.


Subject(s)
DEAD Box Protein 58/immunology , Immune Evasion/genetics , Interferons/immunology , Nucleotidyltransferases/immunology , Receptors, Immunologic/immunology , SARS-CoV-2/immunology , Toll-Like Receptor 3/immunology , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/immunology , Adaptor Proteins, Vesicular Transport/genetics , Adaptor Proteins, Vesicular Transport/immunology , Animals , Chlorocebus aethiops , Coronavirus Nucleocapsid Proteins/genetics , Coronavirus Nucleocapsid Proteins/immunology , DEAD Box Protein 58/genetics , Gene Expression Regulation , HEK293 Cells , HeLa Cells , Humans , I-kappa B Kinase/genetics , I-kappa B Kinase/immunology , Immunity, Innate , Interferon Regulatory Factor-3/genetics , Interferon Regulatory Factor-3/immunology , Interferon-Induced Helicase, IFIH1/genetics , Interferon-Induced Helicase, IFIH1/immunology , Interferons/genetics , Membrane Proteins/genetics , Membrane Proteins/immunology , Nucleotidyltransferases/genetics , Phosphoproteins/genetics , Phosphoproteins/immunology , Plasmids/chemistry , Plasmids/metabolism , /immunology , Receptors, Immunologic/genetics , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity , Signal Transduction/genetics , Signal Transduction/immunology , Toll-Like Receptor 3/genetics , Transfection , Vero Cells , Virus Replication/immunology
7.
Signal Transduct Target Ther ; 6(1): 200, 2021 05 20.
Article in English | MEDLINE | ID: covidwho-1237988

ABSTRACT

Influenza A virus may circulate simultaneously with the SARS-CoV-2 virus, leading to more serious respiratory diseases during this winter. However, the influence of these viruses on disease outcome when both influenza A and SARS-CoV-2 are present in the host remains unclear. Using a mammalian model, sequential infection was performed in ferrets and in K18-hACE2 mice, with SARS-CoV-2 infection following H1N1. We found that co-infection with H1N1 and SARS-CoV-2 extended the duration of clinical manifestation of COVID-19, and enhanced pulmonary damage, but reduced viral shedding of throat swabs and viral loads in the lungs of ferrets. Moreover, mortality was increased in sequentially infected mice compared with single-infection mice. Compared with single-vaccine inoculation, co-inoculation of PiCoVacc (a SARS-CoV-2 vaccine) and the flu vaccine showed no significant differences in neutralizing antibody titers or virus-specific immune responses. Combined immunization effectively protected K18-hACE2 mice against both H1N1 and SARS-CoV-2 infection. Our findings indicated the development of systematic models of co-infection of H1N1 and SARS-CoV-2, which together notably enhanced pneumonia in ferrets and mice, as well as demonstrated that simultaneous vaccination against H1N1 and SARS-CoV-2 may be an effective prevention strategy for the coming winter.


Subject(s)
COVID-19 , Coinfection , Influenza A Virus, H1N1 Subtype/immunology , Orthomyxoviridae Infections , SARS-CoV-2/immunology , Animals , COVID-19/immunology , COVID-19/pathology , COVID-19/virology , Coinfection/immunology , Coinfection/pathology , Coinfection/virology , Disease Models, Animal , Ferrets , Humans , Male , Mice , Mice, Transgenic , Orthomyxoviridae Infections/immunology , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/virology
8.
J Med Virol ; 93(9): 5376-5389, 2021 09.
Article in English | MEDLINE | ID: covidwho-1206842

ABSTRACT

The suppression of types I and III interferon (IFN) responses by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contributes to the pathogenesis of coronavirus disease 2019 (COVID-19). The strategy used by SARS-CoV-2 to evade antiviral immunity needs further investigation. Here, we reported that SARS-CoV-2 ORF9b inhibited types I and III IFN production by targeting multiple molecules of innate antiviral signaling pathways. SARS-CoV-2 ORF9b impaired the induction of types I and III IFNs by Sendai virus and poly (I:C). SARS-CoV-2 ORF9b inhibited the activation of types I and III IFNs induced by the components of cytosolic dsRNA-sensing pathways of RIG-I/MDA5-MAVS signaling, including RIG-I, MDA-5, MAVS, TBK1, and IKKε, rather than IRF3-5D, which is the active form of IRF3. SARS-CoV-2 ORF9b also suppressed the induction of types I and III IFNs by TRIF and STING, which are the adaptor protein of the endosome RNA-sensing pathway of TLR3-TRIF signaling and the adaptor protein of the cytosolic DNA-sensing pathway of cGAS-STING signaling, respectively. A mechanistic analysis revealed that the SARS-CoV-2 ORF9b protein interacted with RIG-I, MDA-5, MAVS, TRIF, STING, and TBK1 and impeded the phosphorylation and nuclear translocation of IRF3. In addition, SARS-CoV-2 ORF9b facilitated the replication of the vesicular stomatitis virus. Therefore, the results showed that SARS-CoV-2 ORF9b negatively regulates antiviral immunity and thus facilitates viral replication. This study contributes to our understanding of the molecular mechanism through which SARS-CoV-2 impairs antiviral immunity and provides an essential clue to the pathogenesis of COVID-19.


Subject(s)
DEAD Box Protein 58/immunology , Immune Evasion/genetics , Interferons/immunology , Nucleotidyltransferases/immunology , Receptors, Immunologic/immunology , SARS-CoV-2/immunology , Toll-Like Receptor 3/immunology , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/immunology , Adaptor Proteins, Vesicular Transport/genetics , Adaptor Proteins, Vesicular Transport/immunology , Animals , Chlorocebus aethiops , Coronavirus Nucleocapsid Proteins/genetics , Coronavirus Nucleocapsid Proteins/immunology , DEAD Box Protein 58/genetics , Gene Expression Regulation , HEK293 Cells , HeLa Cells , Humans , I-kappa B Kinase/genetics , I-kappa B Kinase/immunology , Immunity, Innate , Interferon Regulatory Factor-3/genetics , Interferon Regulatory Factor-3/immunology , Interferon-Induced Helicase, IFIH1/genetics , Interferon-Induced Helicase, IFIH1/immunology , Interferons/genetics , Membrane Proteins/genetics , Membrane Proteins/immunology , Nucleotidyltransferases/genetics , Phosphoproteins/genetics , Phosphoproteins/immunology , Plasmids/chemistry , Plasmids/metabolism , /immunology , Receptors, Immunologic/genetics , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity , Signal Transduction/genetics , Signal Transduction/immunology , Toll-Like Receptor 3/genetics , Transfection , Vero Cells , Virus Replication/immunology
9.
Animal Model Exp Med ; 4(1): 2-15, 2021 03.
Article in English | MEDLINE | ID: covidwho-1122088

ABSTRACT

Background: Cardiovascular diseases (CVDs) and diabetes mellitus (DM) are top two chronic comorbidities that increase the severity and mortality of COVID-19. However, how SARS-CoV-2 alters the progression of chronic diseases remain unclear. Methods: We used adenovirus to deliver h-ACE2 to lung to enable SARS-CoV-2 infection in mice. SARS-CoV-2's impacts on pathogenesis of chronic diseases were studied through histopathological, virologic and molecular biology analysis. Results: Pre-existing CVDs resulted in viral invasion, ROS elevation and activation of apoptosis pathways contribute myocardial injury during SARS-CoV-2 infection. Viral infection increased fasting blood glucose and reduced insulin response in DM model. Bone mineral density decreased shortly after infection, which associated with impaired PI3K/AKT/mTOR signaling. Conclusion: We established mouse models mimicked the complex pathological symptoms of COVID-19 patients with chronic diseases. Pre-existing diseases could impair the inflammatory responses to SARS-CoV-2 infection, which further aggravated the pre-existing diseases. This work provided valuable information to better understand the interplay between the primary diseases and SARS-CoV-2 infection.


Subject(s)
COVID-19/complications , COVID-19/physiopathology , Cardiovascular Diseases/complications , Cardiovascular Diseases/physiopathology , Diabetes Complications/physiopathology , Animals , Comorbidity , Diabetes Mellitus , Disease Models, Animal , Male , Mice , SARS-CoV-2
10.
J Infect Dis ; 223(8): 1313-1321, 2021 04 23.
Article in English | MEDLINE | ID: covidwho-1091239

ABSTRACT

Domestic cats, an important companion animal, can be infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This has aroused concern regarding the ability of domestic cats to spread the virus that causes coronavirus disease 2019. We systematically demonstrated the pathogenesis and transmissibility of SARS-CoV-2 in cats. Serial passaging of the virus between cats dramatically attenuated the viral transmissibility, likely owing to variations of the amino acids in the receptor-binding domain sites of angiotensin-converting enzyme 2 between humans and cats. These findings provide insight into the transmissibility of SARS-CoV-2 in cats and information for protecting the health of humans and cats.


Subject(s)
COVID-19/transmission , COVID-19/veterinary , SARS-CoV-2/pathogenicity , Amino Acids/metabolism , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/metabolism , Cats , Cell Line , Chlorocebus aethiops , Female , Humans , Male , Vero Cells
11.
Front Microbiol ; 11: 618891, 2020.
Article in English | MEDLINE | ID: covidwho-1054989

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has spread across the world and impacted global healthcare systems. For clinical patients, COVID-19 not only induces pulmonary lesions but also affects extrapulmonary organs. An ideal animal model that mimics COVID-19 in humans in terms of the induced systematic lesions is urgently needed. Here, we report that Syrian hamster is highly permissive to SARS-CoV-2 and exhibit diffuse alveolar damage and induced extrapulmonary multi-organs damage, including spleen, lymph nodes, different segments of alimentary tract, kidney, adrenal gland, ovary, vesicular gland and prostate damage, at 3-7 days post inoculation (dpi), based on qRT-PCR, in situ hybridization and immunohistochemistry detection. Notably, the adrenal gland is a novel target organ, with abundant viral RNA and antigen expression detected, accompanied by focal to diffuse inflammation. Additionally, viral RNA was also detected in the corpus luteum of the ovary, vesicular gland and prostate. Focal lesions in liver, gallbladder, myocardium, and lymph nodes were still present at 18 dpi, suggesting potential damage after disease. Our findings illustrate systemic histological observations and the viral RNA and antigen distribution in infected hamsters during disease and convalescence to recapitulate those observed in humans with COVID-19, providing helpful data to the pathophysiologic characterization of SARS-CoV-2-induced systemic disease and the development of effective treatment strategies.

12.
Int J Environ Res Public Health ; 17(19)2020 09 30.
Article in English | MEDLINE | ID: covidwho-1000270

ABSTRACT

The COVID-19 pandemic represents a massive global health crisis. The rapid transmission rate of the virus, as well as the lack of effective medications and vaccines, has posed serious challenges to controlling the spread of the disease. Dealing with this public health crisis has required major changes in people's behavior, including the adoption of social distancing measures such as avoiding meeting with family members and friends, crowded places, and public transportation. The purpose of this study is to investigate the factors associated with the adoption of these behaviors in China and Israel. We relied on the 3Cs model that has been used to predict the adoption of a specific preventive behavior (vaccinations) with the goal of testing its applicability to other preventive behaviors such as in response to the COVID-19 pandemic. The model indicates that confidence in social institutions, complacency (fear of and assessments about the risk of becoming ill) and constraints (levels of self-efficacy and confidence in being able to engage in the behaviors) are predictors of adopting preventive behaviors. Data were collected in China and Israel through an online survey of the population (n = 1406). We used latent variables and structural equation modeling to test the hypotheses derived from the 3Cs model. The findings indicate that there are some differences in the types of preventive behaviors adopted in the two countries. In Israel, higher levels of confidence predicted the adoption of avoidant behaviors and more constraints predicted engaging in fewer avoidant behaviors. In China, more constraints also contributed to the adoption of fewer avoidant behaviors, but people's level of confidence fully mediated this result. The multi-group analysis indicated that the conceptualized model fits the Chinese and Israeli data reasonably well. The findings suggest that the 3Cs model can be generalized from getting vaccinated to adopting avoidant behaviors and that the model can be used across cultures and countries.


Subject(s)
Communicable Disease Control/methods , Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Vaccination/psychology , Betacoronavirus , COVID-19 , China , Humans , Israel , SARS-CoV-2 , Social Behavior , Social Isolation
13.
Animal Model Exp Med ; 3(1): 93-97, 2020 Mar.
Article in English | MEDLINE | ID: covidwho-847791

ABSTRACT

BACKGROUND: Since December 2019, an outbreak of the Corona Virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) in Wuhan, China, has become a public health emergency of international concern. The high fatality of aged cases caused by SARS-CoV-2 was a need to explore the possible age-related phenomena with non-human primate models. METHODS: Three 3-5 years old and two 15 years old rhesus macaques were intratracheally infected with SARS-CoV-2, and then analyzed by clinical signs, viral replication, chest X-ray, histopathological changes and immune response. RESULTS: Viral replication of nasopharyngeal swabs, anal swabs and lung in old monkeys was more active than that in young monkeys for 14 days after SARS-CoV-2 challenge. Monkeys developed typical interstitial pneumonia characterized by thickened alveolar septum accompanied with inflammation and edema, notably, old monkeys exhibited diffuse severe interstitial pneumonia. Viral antigens were detected mainly in alveolar epithelial cells and macrophages. CONCLUSION: SARS-CoV-2 caused more severe interstitial pneumonia in old monkeys than that in young monkeys. Rhesus macaque models infected with SARS-CoV-2 provided insight into the pathogenic mechanism and facilitated the development of vaccines and therapeutics against SARS-CoV-2 infection.

14.
Nat Commun ; 11(1): 4400, 2020 09 02.
Article in English | MEDLINE | ID: covidwho-744370

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly transmitted through the respiratory route, but potential extra-respiratory routes of SARS-CoV-2 transmission remain uncertain. Here we inoculated five rhesus macaques with 1 × 106 TCID50 of SARS-CoV-2 conjunctivally (CJ), intratracheally (IT), and intragastrically (IG). Nasal and throat swabs collected from CJ and IT had detectable viral RNA at 1-7 days post-inoculation (dpi). Viral RNA was detected in anal swabs from only the IT group at 1-7 dpi. Viral RNA was undetectable in tested swabs and tissues after intragastric inoculation. The CJ infected animal had a higher viral load in the nasolacrimal system than the IT infected animal but also showed mild interstitial pneumonia, suggesting distinct virus distributions. This study shows that infection via the conjunctival route is possible in non-human primates; further studies are necessary to compare the relative risk and pathogenesis of infection through these different routes in more detail.


Subject(s)
Betacoronavirus/physiology , Conjunctiva/virology , Coronavirus Infections/virology , Disease Models, Animal , Pneumonia, Viral/virology , Animals , Antibodies, Viral , Betacoronavirus/genetics , Betacoronavirus/isolation & purification , COVID-19 , Coronavirus Infections/pathology , Intestine, Large/virology , Lung/pathology , Lung/virology , Macaca mulatta , Male , Nasal Cavity/virology , Pandemics , Pneumonia, Viral/pathology , RNA, Viral/analysis , RNA, Viral/genetics , SARS-CoV-2 , Trachea/virology , Viral Load , Virus Replication
15.
J Infect Dis ; 222(4): 551-555, 2020 07 23.
Article in English | MEDLINE | ID: covidwho-704462

ABSTRACT

We simulated 3 transmission modes, including close-contact, respiratory droplets and aerosol routes, in the laboratory. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be highly transmitted among naive human angiotensin-converting enzyme 2 (hACE2) mice via close contact because 7 of 13 naive hACE2 mice were SARS-CoV-2 antibody seropositive 14 days after being introduced into the same cage with 3 infected-hACE2 mice. For respiratory droplets, SARS-CoV-2 antibodies from 3 of 10 naive hACE2 mice showed seropositivity 14 days after introduction into the same cage with 3 infected-hACE2 mice, separated by grids. In addition, hACE2 mice cannot be experimentally infected via aerosol inoculation until continued up to 25 minutes with high viral concentrations.


Subject(s)
Betacoronavirus , Coronavirus Infections/transmission , Pneumonia, Viral/transmission , Aerosols , Anal Canal/virology , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Viral/blood , Betacoronavirus/genetics , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , COVID-19 , Chlorocebus aethiops , Female , Humans , Immunoglobulin G/blood , Lung/pathology , Lung/virology , Male , Mice , Mice, Transgenic , Pandemics , Peptidyl-Dipeptidase A/genetics , Pharynx/virology , RNA, Viral/isolation & purification , Respiratory System/virology , Risk , SARS-CoV-2 , Specific Pathogen-Free Organisms , Time Factors , Vero Cells , Viral Load , Weight Loss
16.
Science ; 369(6505): 818-823, 2020 08 14.
Article in English | MEDLINE | ID: covidwho-631755

ABSTRACT

Coronavirus disease 2019 (COVID-19), which is caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic. It is unclear whether convalescing patients have a risk of reinfection. We generated a rhesus macaque model of SARS-CoV-2 infection that was characterized by interstitial pneumonia and systemic viral dissemination mainly in the respiratory and gastrointestinal tracts. Rhesus macaques reinfected with the identical SARS-CoV-2 strain during the early recovery phase of the initial SARS-CoV-2 infection did not show detectable viral dissemination, clinical manifestations of viral disease, or histopathological changes. Comparing the humoral and cellular immunity between primary infection and rechallenge revealed notably enhanced neutralizing antibody and immune responses. Our results suggest that primary SARS-CoV-2 exposure protects against subsequent reinfection in rhesus macaques.


Subject(s)
Betacoronavirus , Coronavirus Infections/immunology , Coronavirus Infections/virology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Anal Canal/virology , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , B-Lymphocyte Subsets/immunology , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , Betacoronavirus/physiology , COVID-19 , Coronavirus Infections/pathology , Coronavirus Infections/physiopathology , Disease Models, Animal , Host Microbial Interactions , Immunity, Cellular , Immunity, Humoral , Lung/diagnostic imaging , Lung/immunology , Lung/pathology , Lung/virology , Lung Diseases, Interstitial/immunology , Lung Diseases, Interstitial/pathology , Lung Diseases, Interstitial/virology , Macaca mulatta , Nasopharynx/virology , Pandemics , Pneumonia, Viral/pathology , Pneumonia, Viral/physiopathology , Recurrence , SARS-CoV-2 , T-Lymphocyte Subsets/immunology , Viral Load , Virus Replication
17.
Aging (Albany NY) ; 12(11): 10059-10069, 2020 06 01.
Article in English | MEDLINE | ID: covidwho-459080

ABSTRACT

AIM: To evaluate the clinical value of abnormal laboratory results of multiple organs in patients with coronavirus disease 2019 (COVID-2019) and to help clinicians perform correct treatment. RESULTS: Elevated neutrophil-to-LYM ratio (NLR), D-dimer(D-D), interleukin (IL)-6, IL-10, IL-2, interferon-Y, and age were significantly associated with the severity of illness. However, significant and sustained decreases were observed in the LYM subset (p<0.05). D-D, T cell counts, and cytokine levels in severe COVID-19 patients who survived the disease gradually recovered at later time points to levels that were comparable to those of mild cases. Second, D-D increased from 0.5 to 8, and the risk ratio increased from 2.75 to 55, eventually leading to disseminated intravascular coagulation. Moreover, the acute renal function damage occurred earlier than abnormal heart and liver functions (p<0.05). CONCLUSIONS: The degrees of lymphopenia and proinflammatory cytokine storm were higher in severe COVID-19 patients than in mild cases. The degree was associated with the disease severity. Advanced age, NLR, D-D, and cytokine levels may serve as useful prognostic factors for the early identification of severe COVID-19 cases. METHODS: Peripheral blood samples were collected from 93 confirmed COVID-19 patients. The samples were examined for lymphocyte (LYM) subsets by flow cytometry and cytokine profiles by specific immunoassays. The receiver operating characteristic curve was applied to determine the best diagnostic thresholds for laboratory results, and principal component analysis was used to screen the major risk factors. The prognostic values were assessed using the Kaplan-Meier curve and univariate and multivariate COX regression models.


Subject(s)
Betacoronavirus/physiology , Coronavirus Infections/blood , Cytokines/blood , Host-Pathogen Interactions , Pneumonia, Viral/blood , Adult , Aged , COVID-19 , China/epidemiology , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Pneumonia, Viral/immunology , Prognosis , Retrospective Studies , SARS-CoV-2
18.
Nature ; 583(7818): 830-833, 2020 07.
Article in English | MEDLINE | ID: covidwho-220333

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which has become a public health emergency of international concern1. Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for severe acute respiratory syndrome coronavirus (SARS-CoV)2. Here we infected transgenic mice that express human ACE2 (hereafter, hACE2 mice) with SARS-CoV-2 and studied the pathogenicity of the virus. We observed weight loss as well as virus replication in the lungs of hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of considerable numbers of macrophages and lymphocytes into the alveolar interstitium, and the accumulation of macrophages in alveolar cavities. We observed viral antigens in bronchial epithelial cells, macrophages and alveolar epithelia. These phenomena were not found in wild-type mice infected with SARS-CoV-2. Notably, we have confirmed the pathogenicity of SARS-CoV-2 in hACE2 mice. This mouse model of SARS-CoV-2 infection will be valuable for evaluating antiviral therapeutic agents and vaccines, as well as understanding the pathogenesis of COVID-19.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/pathology , Coronavirus Infections/virology , Lung/pathology , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Transgenes , Angiotensin-Converting Enzyme 2 , Animals , Antigens, Viral/immunology , Antigens, Viral/metabolism , Betacoronavirus/immunology , Betacoronavirus/metabolism , Bronchi/pathology , Bronchi/virology , COVID-19 , Coronavirus Infections/immunology , Disease Models, Animal , Epithelial Cells/pathology , Epithelial Cells/virology , Female , Humans , Immunoglobulin G/immunology , Lung/immunology , Lung/virology , Lymphocytes/immunology , Macrophages, Alveolar/immunology , Macrophages, Alveolar/virology , Male , Mice , Mice, Transgenic , Pandemics , Pneumonia, Viral/immunology , Receptors, Complement 3d/genetics , Receptors, Complement 3d/metabolism , SARS-CoV-2 , Virus Replication , Weight Loss
20.
Chin. Trad. Herbal Drugs ; 5(51): 1147-1152, 20200312.
Article in Chinese | WHO COVID, ELSEVIER | ID: covidwho-52361

ABSTRACT

To dig out and analyze the drug rule of COVID-19 prevention prescriptions from provinces and cities by using Traditional Chinese Medicine Inheritance Support System, summarize and explore its potential new prescription. The Chinese medicine prevention programs for COVID-19 were collected and searched from the official website of the Health Commission and State Administration Medicine of Traditional Chinese Medicine of the country and provinces, autonomous regions, and municipalities. TCM prevention programs in 17 provinces including Heilongjiang, Beijing, Tianjin, Hebei, Henan, Jiangxi, Sichuan, Hubei, and Hunan, etc were received. A total of 82 herbs were included in 64 prescriptions, the most frequently used Chinese herbs were Astragalus membranaceus, Lonicera japonica, etc. Tonifying deficiency drugs with sweet and warm natures were used the most, the Chinese herbs distributed in the lung channel was the most in channel tropism drugs. Analysis by association rule, eight combinations of commonly used drugs were obtained. Based on entropy clustering method rule analysis, seven potential new prescriptions were obtained. Tonifying deficiency drugs are often used in various places to prevent COVID-19, focusing on the lung, spleen and stomach. Although the specific details are different, they all reflect the preventive thinking of traditional Chinese medicine.

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