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2.
Nat Commun ; 14(1): 2962, 2023 05 23.
Article in English | MEDLINE | ID: covidwho-20243557

ABSTRACT

Herd immunity achieved through mass vaccination is an effective approach to prevent contagious diseases. Nonetheless, emerging SARS-CoV-2 variants with frequent mutations largely evaded humoral immunity induced by Spike-based COVID-19 vaccines. Herein, we develop a lipid nanoparticle (LNP)-formulated mRNA-based T-cell-inducing antigen, which targeted three SARS-CoV-2 proteome regions that enriched human HLA-I epitopes (HLA-EPs). Immunization of HLA-EPs induces potent cellular responses to prevent SARS-CoV-2 infection in humanized HLA-A*02:01/DR1 and HLA-A*11:01/DR1 transgenic mice. Of note, the sequences of HLA-EPs are highly conserved among SARS-CoV-2 variants of concern. In humanized HLA-transgenic mice and female rhesus macaques, dual immunization with the LNP-formulated mRNAs encoding HLA-EPs and the receptor-binding domain of the SARS-CoV-2 B.1.351 variant (RBDbeta) is more efficacious in preventing infection of SARS-CoV-2 Beta and Omicron BA.1 variants than single immunization of LNP-RBDbeta. This study demonstrates the necessity to strengthen the vaccine effectiveness by comprehensively stimulating both humoral and cellular responses, thereby offering insight for optimizing the design of COVID-19 vaccines.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Mice , Female , Humans , COVID-19 Vaccines , Macaca mulatta , Epitopes , Antibodies , Mice, Transgenic , T-Lymphocytes , HLA-A Antigens
3.
Front Immunol ; 14: 1196031, 2023.
Article in English | MEDLINE | ID: covidwho-20236991

ABSTRACT

Swine acute diarrhoea syndrome coronavirus (SADS-CoV), which is a recently discovered enteric coronavirus, is the major aetiological agent that causes severe clinical diarrhoea and intestinal pathological damage in pigs, and it has caused significant economic losses to the swine industry. Nonstructural protein 5, also called 3C-like protease, cleaves viral polypeptides and host immune-related molecules to facilitate viral replication and immune evasion. Here, we demonstrated that SADS-CoV nsp5 significantly inhibits the Sendai virus (SEV)-induced production of IFN-ß and inflammatory cytokines. SADS-CoV nsp5 targets and cleaves mRNA-decapping enzyme 1a (DCP1A) via its protease activity to inhibit the IRF3 and NF-κB signaling pathways in order to decrease IFN-ß and inflammatory cytokine production. We found that the histidine 41 and cystine 144 residues of SADS-CoV nsp5 are critical for its cleavage activity. Additionally, a form of DCP1A with a mutation in the glutamine 343 residue is resistant to nsp5-mediated cleavage and has a stronger ability to inhibit SADS-CoV infection than wild-type DCP1A. In conclusion, our findings reveal that SADS-CoV nsp5 is an important interferon antagonist and enhance the understanding of immune evasion by alpha coronaviruses.


Subject(s)
Alphacoronavirus , Coronavirus , Interferon Type I , Animals , Swine , Alphacoronavirus/genetics , Alphacoronavirus/metabolism , Coronavirus/metabolism , Endopeptidases , Interferon Type I/metabolism
4.
Pharmaceutics ; 15(5)2023 May 05.
Article in English | MEDLINE | ID: covidwho-20232301

ABSTRACT

Neutralizing antibodies (nAbs), the popular antiviral drugs used for the treatment of COVID-19, are effective in reducing viral load and hospitalization. Currently, most nAbs are screened from convalescent or vaccinated individuals through single B-cell sequencing which requires cutting-edge facilities. Moreover, owing to the rapid mutation of SARS-CoV-2, some approved nAbs are no longer effective. In the present study, we designed a new approach to acquiring broadly neutralizing antibodies (bnAbs) from mRNA-vaccinated mice. Using the flexibility and speed of mRNA vaccine preparation, we designed a chimeric mRNA vaccine and sequential immunization strategies to acquire bnAbs in mice within a short period. By comparing different vaccination orders, we found that the initially administered vaccine had a greater effect on the neutralizing potency of mouse sera. Ultimately, we screened a strain of bnAb that neutralized wild-type, Beta, and Delta SARS-CoV-2 pseudoviruses. We synthesized the mRNAs of the heavy and light chains of this antibody and verified its neutralizing potency. This study developed a new strategy to screen for bnAbs in mRNA-vaccinated mice and identified a more effective immunization strategy for inducing bnAbs, providing valuable insights for future antibody drug development.

6.
World J Acupunct Moxibustion ; 2023 Mar 17.
Article in English | MEDLINE | ID: covidwho-2298703

ABSTRACT

Chronic fatigue syndrome is a neurological disorder characterized by extreme fatigue that lasts for a long time and doesn't alleviate with rest. The number of the cases has been increasing during the era of COVID-19 pandemic. Acupuncture may have some effect on chronic fatigue syndrome, but its mechanism remains unclear. This article was to summarize the specific manifestations of abnormal central mechanism in patients with chronic fatigue syndrome through laboratory tests and neuroimaging. It was found from the laboratory evaluation that there were changes in the structure of the frontal cortex, thalamus and other brain tissues; factors, including IFN-α and IL-10 in cerebrospinal fluid were found abnormal; results of oxidative and nitrosative stress and changes in neurobiochemical substances, e.g. hypothalamus hormone levels and neurotransmitter concentrations, were observed. With magnetic resonance imaging and positron emission tomography, it was shown that the partial brain of persons with chronic fatigue syndrome had morphological changes with diminished grey matter and white; changes in cerebral blood flow velocity caused by decreased perfusion and functional activity with abnormal connectivity in brain were detected. In addition, there was significant decrease in glucose metabolism accompanied with neuroinflammatory response; metabolic disorders of serotonergic, cholinergic, glutamatergic and γ-aminobutyric acid energy neurotransmitters were also discovered. The regulatory effect of acupuncture on the above central neurological abnormalities in chronic fatigue syndrome model animals was elaborated, and the direction for further research was analyzed in order to provide ideas for further research on the central mechanism of acupuncture treatment for chronic fatigue syndrome.

7.
World Journal of Acupuncture-Moxibustion ; 2023.
Article in English | EuropePMC | ID: covidwho-2268629

ABSTRACT

Chronic fatigue syndrome is a neurological disorder characterized by extreme fatigue that lasts for a long time and doesn't alleviate with rest. The number of the cases has been increasing during the era of COVID-19 pandemic. Acupuncture may have some effect on chronic fatigue syndrome, but its mechanism remains unclear. This article was to summarize the specific manifestations of abnormal central mechanism in patients with chronic fatigue syndrome through laboratory tests and neuroimaging. It was found from the laboratory evaluation that there were changes in the structure of the frontal cortex, thalamus and other brain tissues;factors, including IFN-α and IL-10 in cerebrospinal fluid were found abnormal;results of oxidative and nitrosative stress and changes in neurobiochemical substances, e.g. hypothalamus hormone levels and neurotransmitter concentrations, were observed. With magnetic resonance imaging and positron emission tomography, it was shown that the partial brain of persons with chronic fatigue syndrome had morphological changes with diminished grey matter and white;changes in cerebral blood flow velocity caused by decreased perfusion and functional activity with abnormal connectivity in brain were detected. In addition, there was significant decrease in glucose metabolism accompanied with neuroinflammatory response;metabolic disorders of serotonergic, cholinergic, glutamatergic and γ-aminobutyric acid energy neurotransmitters were also discovered. The regulatory effect of acupuncture on the above central neurological abnormalities in chronic fatigue syndrome model animals was elaborated, and the direction for further research was analyzed in order to provide ideas for further research on the central mechanism of acupuncture treatment for chronic fatigue syndrome.

8.
BMJ Open ; 13(2): e067910, 2023 Feb 24.
Article in English | MEDLINE | ID: covidwho-2280746

ABSTRACT

OBJECTIVE: To evaluate the effect of colchicine and high-intensity rosuvastatin in addition to standard of care on the progression of COVID-19 disease in hospitalised patients. DESIGN: A pragmatic, open-label, multicentre, randomised controlled trial conducted from October 2020 to September 2021. Follow-up was conducted at 30 and 60 days. The electronic medical record was used at all stages of the trial including screening, enrolment, randomisation, event ascertainment and follow-up. SETTING: Four centres in the Yale New Haven Health System. PARTICIPANTS: Non-critically ill hospitalised patients with COVID-19. INTERVENTIONS: Patients were randomised 1:1 to either colchicine plus high-intensity rosuvastatin in addition to standard of care versus standard of care alone. Assigned treatment was continued for the duration of index hospitalisation or 30 days, whichever was shorter. PRIMARY AND SECONDARY OUTCOME MEASURES: The prespecified primary endpoint was progression to severe COVID-19 disease (new high-flow or non-invasive ventilation, mechanical ventilation, need for vasopressors, renal replacement therapy or extracorporeal membrane oxygenation, or death) or arterial/venous thromboembolic events (ischaemic stroke, myocardial infarction, deep venous thrombosis or pulmonary embolism) evaluated at 30 days. RESULTS: Among the 250 patients randomised in this trial (125 to each arm), the median age was 61 years, 44% were women, 15% were Black and 26% were Hispanic/Latino. As part of the standard of care, patients received remdesivir (87%), dexamethasone (92%), tocilizumab (18%), baricitinib (2%), prophylactic/therapeutic anticoagulation (98%) and aspirin (91%). The trial was terminated early by the data and safety monitoring board for futility. No patients were lost to follow-up due to electronic medical record follow-up. There was no significant difference in the primary endpoint at 30 days between the active arm and standard of care arm (15.2% vs 8.8%, respectively, p=0.17). CONCLUSIONS: In this small, open-label, randomised trial of non-critically ill hospitalised patients with COVID-19, the combination of colchicine and rosuvastatin in addition to standard of care did not appear to reduce the risk of progression of COVID-19 disease or thromboembolic events, although the trial was underpowered due to a lower-than-expected event rate. The trial leveraged the power of electronic medical records for efficiency and improved follow-up and demonstrates the utility of incorporating electronic medical records into future trials. TRIAL REGISTRATION: NCT04472611.


Subject(s)
Brain Ischemia , COVID-19 , Stroke , Female , Humans , Middle Aged , Male , Rosuvastatin Calcium , SARS-CoV-2 , Colchicine , Treatment Outcome
9.
Asian Review of Accounting ; 31(1):57-85, 2023.
Article in English | ProQuest Central | ID: covidwho-2232734

ABSTRACT

PurposeThis paper investigates whether sustainability performance (SP) protects financial performance (FP) for firms in both developed and emerging economies during the COVID-19-induced economic downturn.Design/methodology/approachUsing a recent sample of firms in 34 countries between 2003 and 2021, the authors employ ordinary least squares regressions, moderations and the Heckman two-step method to test the hypotheses.FindingsFirms with strong SP have higher FP in developed and emerging economies in the upcoming year. During the COVID-19 crisis in 2020–2021, the impact of sustainability on FP is pronounced in developed but not in emerging economies. Furthermore, cross-listings expose firms in emerging economies to high-standard institutional mechanisms in developed economies. Thus, sustainable firms in emerging economies cross-listed on European stock exchanges are more profitable.Practical implicationsFor regulators and standard setters, the global-level comparative analysis helps them find solutions that may assist firms in improving SP globally (e.g. mandatory reporting) and enduring crises resiliently. For institutional investors, the study reveals the relatively different impact of sustainability risk for firms in developed and emerging economies. For practitioners and private sector firms, this study contributes to the dialogue on what makes firms more resilient in COVID-19. Although COVID-19 might be temporary, the lessons learned could protect firms from future crises.Originality/valueThe authors contribute to the contingency perspective between sustainability and financial performance by providing recent empirical evidence in a global setting during the COVID-19 pandemic. The authors demonstrate how different external institutional mechanisms (rule-based governance and relation-based governance) and cross-listing affect the SP-FP relationship during a crisis. The authors extend the knowledge in crisis management literature with a comparative study and fill the research gap on how SP affects FP for firms in emerging economies compared to developed economies.

11.
Pulm Circ ; 13(1): e12187, 2023 Jan.
Article in English | MEDLINE | ID: covidwho-2219860

ABSTRACT

We examined the efficacy and safety of Liushen pill combined with basic treatment for patients with COVID-19. In total, 181 patients hospitalized with COVID-19, classified as asymptomatic mild type, were randomly divided into the experimental (n = 91) and control (n = 90) groups and were administered placebo (Maizao decoction) and Maizao decoction and Liushen pill, in addition to standard care, respectively. The negative conversion rate of nucleic acid (Day 7), hospital discharge rate (Days 8, 10, and 14), symptom disappearance rate (Days 3, 5, and 7), inflammatory cytokine levels, and adverse events were compared between the groups. The negative viral conversion rate was significantly higher in the experimental than in the control group (48.35 vs. 31.11%, p < 0.05). Subgroup analysis showed a similar significant trend when the Ct value was ≤30 at baseline. After 10 days, the hospital discharge rate was significantly higher in the experimental than in the control group (69.23 vs. 53.33%, p < 0.05). After 3-day medication, the headache symptoms significantly disappeared in the experimental (88.57%) compared to the control group (63.33%) (p < 0.05). After 5 days, the symptom disappearance rates of headache and cough were significantly higher in the experimental (97.14%) than in the control group (97.14 vs. 80.00, p < 0.05; 82.65 vs. 58.93%, p < 0.01, respectively). Posttreatment, the procalcitonin level was significantly lower in the experimental than in the control group (0.09 ± 0.00 vs. 0.14 ± 0.05 ng/L; p < 0.05). There were no significant between-group differences in clinical safety test indices. Early intervention with Liushen pill improved cough and headache and increased negative viral conversion and discharge rate.

12.
Virol J ; 20(1): 18, 2023 01 31.
Article in English | MEDLINE | ID: covidwho-2224187

ABSTRACT

Coronavirus disease 2019 is a global pandemic caused by SARS-CoV-2. The emergence of its variant strains has posed a considerable challenge to clinical treatment. Therefore, drugs capable of inhibiting SARS-CoV-2 infection, regardless of virus variations, are in urgently need. Our results showed that the endosomal acidification inhibitor, Bafilomycin A1 (Baf-A1), had an inhibitory effect on the viral RNA synthesis of SARS-CoV-2, and its Beta and Delta variants at the concentration of 500 nM. Moreover, the human lung xenograft mouse model was used to investigate the anti-SARS-CoV-2 effect of Baf-A1. It was found that Baf-A1 significantly inhibited SARS-CoV-2 replication in the human lung xenografts by in situ hybridization and RT-PCR assays. Histopathological examination showed that Baf-A1 alleviated SARS-CoV-2-induced diffuse inflammatory infiltration of granulocytes and macrophages and alveolar endothelial cell death in human lung xenografts. In addition, immunohistochemistry analysis indicated that Baf-A1 decreased inflammatory exudation and infiltration in SARS-CoV-2-infected human lung xenografts. Therefore, Baf-A1 may be a candidate drug for SARS-CoV-2 treatment.


Subject(s)
COVID-19 , Humans , Animals , Mice , Heterografts , SARS-CoV-2 , Alveolar Epithelial Cells , Disease Models, Animal
13.
Glob Ment Health (Camb) ; 9: 37, 2022.
Article in English | MEDLINE | ID: covidwho-2185041

ABSTRACT

[This corrects the article DOI: 10.1017/gmh.2021.23.].

14.
Vaccines (Basel) ; 10(10)2022 Sep 23.
Article in English | MEDLINE | ID: covidwho-2044042

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has imposed enormous morbidity and mortality burdens. Patients with rheumatic diseases (RDs) are vulnerable to the COVID-19 infection, given their immunocompromised status. Ensuring acceptance of the COVID-19 vaccine is important and has attracted attention by health professionals. In this study, we designed an online cross-sectional survey that used an online questionnaire from 8 May 2021 to 4 October 2021. Attitudes toward the COVID-19 vaccination, personal information, current disease activity status, adverse events (AEs), and knowledge sources of vaccines were collected. Descriptive statistics, nonparametric tests, and ordinal logistic regression were used to analyze the data. A total of 1022 questionnaires were received, among which 70.2% (720/1022) of patients with RDs agreed to vaccination, while only 31.6% of patients were actually vaccinated. Male, employed, high-income patients and those with inactive disease showed a more positive attitude. Concerns of AEs and disease flare were the main factors affecting vaccination willingness. Only 29.6% (304/1022) of patients thought they had received enough information about the COVID-19 vaccine from their doctors. In conclusion, most patients with RDs in China intended to get vaccinated, although the vaccination rate in this particular population was low. Rheumatologists should take more responsibility in COVID-19 vaccination education of patients with RDs.

15.
Arch Pharm Res ; 45(9): 631-643, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-2035372

ABSTRACT

(±)-Decumicorine A (1) and (±)-epi-decumicorine A (2), two pairs of enantiomeric isoquinoline alkaloids featuring a novel phenylpropanoid-conjugated protoberberine skeleton, were isolated and purified from the rhizomes of Corydalis decumbens. The separation of (±)-1 and (±)-2 was achieved by chiral HPLC to produce four optically pure enantiomers. The structures and absolute configurations of compounds (-)-1, (+)-1, (-)-2, and (+)-2 were elucidated by spectroscopic analysis, ECD calculations, and X-ray crystallographic analyses. The two racemates were generated from a Diels-Alder [4 + 2] cycloaddition between jatrorrhizine and ferulic acid in the proposed biosynthetic pathways, which were fully verified by a biomimetic synthesis. Moreover, compound (+)-1 exhibited an antiviral entry effect on SARS-CoV-2 pseudovirus by blocking spike binding to the ACE2 receptor on HEK-293T-ACE2h host cells.


Subject(s)
Alkaloids , COVID-19 Drug Treatment , Corydalis , Alkaloids/chemistry , Angiotensin-Converting Enzyme 2 , Antiviral Agents/pharmacology , Berberine Alkaloids , Biomimetics , Corydalis/chemistry , Humans , Isoquinolines , Molecular Structure , Rhizome , SARS-CoV-2
16.
Ocean & Coastal Management ; 213:105851, 2021.
Article in English | ScienceDirect | ID: covidwho-1400456

ABSTRACT

Rapid development of maritime transportation networks meets international trade demands while rendering them in high risk and disruption concerns particularly at ports being the bottlenecks of the whole flows. Port operations calls for an effective approach to assess ports vulnerability and to ensure the resilience of their associated maritime supply chains (MSC). However, traditional quantitative risk analysis reveals challenges due to data incompleteness and ambiguity, and operational and environmental uncertainty when being applied in ports vulnerability analysis. This paper aims to develop a novel port vulnerability assessment (PVA) framework, which can guide and realise a standardised vulnerability analysis process for the ports from different geographies involving in the same MSC and hence the resources can be better managed from a global network level for optimal resilience of the chain. It is especially important for the shipping and port industries which are in nature international and desires strong international uniform standardization. The fuzzy theory, evidential reasoning (ER) approach, and expected utility theory are combined in a holistic way to form the proposed PVA framework. The new framework is validated and demonstrated by using a case study in which five key ports along an established MSC in China are investigated. The findings can be used as a stand along method to compare the vulnerability levels of the ports in an MSC and/or integrated with decision optimisation methods for rational safety resource distribution from a supply chain perspective.

17.
Heliyon ; 8(6): e09660, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1882050

ABSTRACT

Recent research efforts have shown that tea has activities against SARS-CoV-2. However, the active compounds and the action mechanisms are largely unknown. Here we study the inhibitory potential of L-theanine from tea and its semi-synthesized derivative, a small-molecule fluorescent compound, ethyl 6-bromocoumarin-3-carboxylyl L-theanine (TBrC) against infection and replication of SARS-CoV-2 and the underlying mechanisms of action. We reveal that TBrC has potential activities against SARS-CoV-2 in addition to its activity against lung cancer. TBrC showed extracellular inhibition of SARS-CoV-2 Mpro/3CL and the host cell receptor ACE2 while interacting with the viral spike glycoproteins (wild-type, Delta, and Omicron mutants). Moreover, TBrC and L-theanine significantly suppressed growth and TNFα-induced nuclear transcriptional activation of NF-κB in human lung cancer cells without affecting the viability of normal lung cells, suggesting a potential protection of TBrC and L-theanine from pulmonary damages in SARS-CoV-2 infected patients, especially for lung cancer patients with SARS-CoV-2 infection.

18.
Arch Gerontol Geriatr ; 102: 104746, 2022.
Article in English | MEDLINE | ID: covidwho-1881095

ABSTRACT

BACKGROUND: Care fragmentation in the elderly population prompted the need for integrated health care systems. However, evidence regarding the impact of the integrated care system in Taiwan is unclear. We aimed to conduct a systematic review to evaluate the impact of Taiwan's integrated health care programs on geriatric population. METHODS: We searched bibliographic databases MEDLINE, Embase, Web of Science, and Airiti Library for relevant publications throughout May 2022. Studies investigating the effectiveness of Taiwan's integrated care programs were included. We used the critical appraisal skills programme (CASP) checklist, to assess the risk of bias of included studies. RESULTS: Thirty-four studies, with a total of 838,026 study subjects, were assessed. The systematic review on 11 subthemes (diabetes mellitus, chronic kidney disease, hepatitis C virus, fractures, cancer, dementia, atrial fibrillation, chronic obstructive pulmonary disease, mechanical ventilation, terminal illness, outpatients and community-dwelling patients), demonstrated that the implementation of integrated health care could not only provide benefits on survival, self-care ability, health quality, physical, and functional rehabilitation outcomes, but also significantly reduce medical utilization and expenditures. CONCLUSION: The integrated health care system for multiple morbidities benefits the Taiwanese geriatric population in physical and functional outcomes. The thematic synthesis provides references for future rigorous clinical trials.


Subject(s)
Delivery of Health Care , Health Expenditures , Aged , Humans , Taiwan/epidemiology
19.
Cell Discov ; 8(1): 53, 2022 Jun 06.
Article in English | MEDLINE | ID: covidwho-1878521

ABSTRACT

The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important target for vaccine and drug development. However, the rapid emergence of variant strains with mutated S proteins has rendered many treatments ineffective. Cleavage of the S protein by host proteases is essential for viral infection. Here, we discovered that the S protein contains two previously unidentified Cathepsin L (CTSL) cleavage sites (CS-1 and CS-2). Both sites are highly conserved among all known SARS-CoV-2 variants. Our structural studies revealed that CTSL cleavage promoted S to adopt receptor-binding domain (RBD) "up" activated conformations, facilitating receptor-binding and membrane fusion. We confirmed that CTSL cleavage is essential during infection of all emerged SARS-CoV-2 variants (including the recently emerged Omicron variant) by pseudovirus (PsV) infection experiment. Furthermore, we found CTSL-specific inhibitors not only blocked infection of PsV/live virus in cells but also reduced live virus infection of ex vivo lung tissues of both human donors and human ACE2-transgenic mice. Finally, we showed that two CTSL-specific inhibitors exhibited excellent In vivo effects to prevent live virus infection in human ACE2-transgenic mice. Our work demonstrated that inhibition of CTSL cleavage of SARS-CoV-2 S protein is a promising approach for the development of future mutation-resistant therapy.

20.
Journal of Shandong University ; 58(4):65-70, 2020.
Article in English, Chinese | GIM | ID: covidwho-1812835

ABSTRACT

Objective: To investigate the clinical characteristics of corona virus disease 2019 (COVID-19) patients in Wuhan City, and the correlation between inflammatory factors and severity.

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