Oridonin inhibits SARS-CoV-2 replication by targeting viral proteinase and polymerase.

COVID-19 has become a global public health crisis since its outbreak in China in December 2019. Currently there are few clinically effective drugs to combat SARS-CoV-2 infection. The main protein (Mpro), papain-like protease (PLpro) and RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 are involved in the viral replication, and might be prospective targets for anti-coronavirus drug development. Here, we investigated the antiviral activity of oridonin, a natural small-molecule compound, against SARS-CoV-2 infection in vitro. The time-of-addition analysis showed that oridonin efficiently inhibited SARS-CoV-2 infection by interfering with the genome replication at the post-entry stage. Mechanistically, the inhibition of viral replication by oridonin depends on the oxidation activity of α, ß-unsaturated carbonyl. Further experiments showed that oridonin not only effectively inhibited SARS-CoV-2 Mpro activity, but also had some inhibitory effects on PLpro-mediated deubiquitinating and viral polymerase-catalyzed RNA elongation activities at high concentrations. In particular, oridonin could inhibit the bat SARS-like CoV and the newly emerged SARS-CoV-2 omicron variants (BA.1 and BA.2), which highlights its potential as a pan-coronavirus antiviral agent. Overall, our data provide strong evidence that oridonin is an efficient antiviral agent against SARS-CoV-2 infection.

Auranofin Has Advantages over First-Line Drugs in the Treatment of Severe Streptococcus suis Infections.

Streptococcal toxic shock-like syndrome (STSLS) likely occurs when an individual is infected with the Streptococcus suis (S. suis) epidemic strain and is characterized by a cytokine storm, multiple organ dysfunction syndrome (MODS) and a high incidence of mortality despite adequate treatment. A number of antibiotics exhibit excellent bactericidal effects in vivo, such as fluoroquinolones, aminoglycosides (gentamicin) and ß-lactams (penicillin G, ceftiofur, or amoxicillin), but are less effective for treating STSLS. Therefore, there is an urgent need to identify new compounds that can reduce the damage caused by STSLS. In the present study, we identified auranofin, an orally bioavailable FDA-approved anti-rheumatic drug as a candidate repurposed drug to treat severe S. suis infections. Our results showed that auranofin can bind to the functional domain of bacterial thioredoxin reductase, decreasing the reducing redox-responsive capacity of target bacteria and allowing for the killing of S. suis cells. We also observed that auranofin has antibacterial activity against other gram-positive bacteria, such as multidrug resistant Streptococcus pneumoniae (MDRSP), Streptococcus agalactiae, and vancomycin-resistant strains of Staphylococcus aureus. Additionally, auranofin is capable of eradicating intracellular S.suis present inside infected macrophage cells. Mouse model experimental results showed that auranofin could effectively reduce the mortality of mice infected with S. suis. Compared to the ampicillin treatment group, the survival rate of mice in the auranofin treatment group in severely infected model mice was significantly improved. These results suggest that auranofin has the potential for use as an effective antibiotic against S. suis.

The Politicization of COVID-19 Origin Stories: Insights from a Cross-Sectional Survey in China

The search for the origins of COVID-19 has yielded no conclusive evidence. In the face of this uncertainty, other social and political factors can influence perceptions of virus origins, which in turn can influence policy formation and global efforts to combat future pandemics. Vastly different COVID-19 origin stories may circulate both within the same country but also between different countries. This article examines COVID-19 origins debates as they circulate in China, drawing from a 974-respondent survey conducted in mainland China. Our results show that within China there is a strong belief that COVID-19 originated outside the country, either in the United States or Europe. This contrasts with mainstream media coverage in the United State and Europe, which generally holds that the virus most likely originated in China. Given such global dissonance, moving forward with pandemic prevention reforms is challenging. Yet, even in the face of such diverse beliefs, building support for reform is still possible. As the search for COVID-19 continues, policy reform can be pursued across a plurality of domains, including wet markets, the wildlife trade, cold-chain products, and gain-of-function virology research, all in the interest of preventing the next global pandemic.

Intranasal delivery of replicating mRNA encoding hACE2-targeting antibody against SARS-CoV-2 Omicron infection in the hamster.

The Omicron variant is sweeping the world, which displays striking immune escape potential through mutations at key antigenic sites on the spike protein, making broad-spectrum SARS-CoV-2 prevention or therapeutical strategies urgently needed. Previously, we have reported a hACE2-targeting neutralizing antibody 3E8, which could efficiently block both prototype SARS-CoV-2 and Delta variant infections in prophylactic mouse models, having the potential of broad-spectrum to prevent SARS-CoV-2. However, preparation of monoclonal neutralizing antibodies is severely limited by the time-consuming process and the relative high cost. Here, we utilized a modified VEEV replicon with two subgenomic (sg) promoters engineered to express the light and heavy chains of the 3E8 mAb. The feasibility and protective efficacy of replicating mRNA encoding 3E8 against Omicron infection in the hamster were demonstrated through the lung targeting delivery with the help of VEEV-VRP. Overall, we developed a safe and cost-effective platform of broad-spectrum to prevent SARS-CoV-2 infection.

The effectiveness of online team-based learning in introduction to medical ethics education for medical students at a medical college of Nepal: a pilot study.

BACKGROUND: The effectiveness of online classes is always a concern, and it can be overcome by opting for active learning strategies like team-based learning (TBL). This study was conducted to find out the effectiveness of online TBL as an active learning strategy. We also aimed to explore the satisfaction and perception of students toward TBL. METHODS: This is a mixed-method study conducted among 29 third-year Bachelor of Medicine and Bachelor of Surgery (MBBS) students of Gandaki Medical College using purposive sampling method in the duration of January to September 2021. Three two hours online TBL sessions were used for teaching introduction to medical ethics. The individual readiness assurance test (IRAT) scores were compared to the group readiness assurance test (GRAT) scores to evaluate the effect of TBL through cooperative learning. Learner reactions and satisfaction of students towards TBL were assessed using a validated questionnaire comprising of a five-point Likert scale. An open-ended question asking the participants to describe their overall experience of the TBL sessions was also included to explore their perceptions towards TBL. The data were collected using Google form and exported to Microsoft Excel and the quantitative data were then analyzed using Statistical Package for Social Sciences (SPSS) version 16.0. To check the normal distribution of the data, Kolmogorov Smirnov and Shapiro-Wilk test were used. Non-parametric tests were used for the non-normally distributed data. P value of < 0.05 was regarded as significant. Thematic analysis was conducted for the qualitative data. RESULTS: The median GRAT scores were significantly higher (p = 0.006 in TBL 1 and 0.001 in TBL 2) than IRAT scores. Learner reactions toward TBL sessions were positive as shown by the mean scores which were in the range of 3.59 to 4.66. Five themes were generated from the codes: "effective learning method", "positive experience", "gained knowledge", "expression of gratitude" and "the way of conduction of the sessions". CONCLUSION: Online TBL in medical ethics was effective as a teaching learning tool in our setting. The students were satisfied with the learning process and rated the learning strategy positively.

Cardiac involvement in patients recovering from Delta Variant of COVID-19: a prospective multi-parametric MRI study.

AIMS: The cardiac injury and sequelae of Delta Variant of coronavirus disease 2019 (COVID-19) remain unknown. This study aimed to evaluate the presence of cardiac involvement in patients recovering from Delta Variant of COVID-19 based on multi-parametric cardiac magnetic resonance imaging (MRI). METHODS AND RESULTS: We prospectively assessed patients recovering from Delta Variant of COVID-19 using multi-parametric cardiac magnetic resonance imaging (MRI) between June 2021 and July 2021. Comparison was made with 25 healthy controls. Forty-four patients (median age 51 years, 28 women) recovering from Delta Variant were recruited and had a median time of 35 days between diagnosis and cardiac MRI. There were no patients with chest pain (0/44, 0%) and high sensitivity cardiac troponin T troponin elevation (median levels 2.20 pg/mL, IQR levels 0.85-4.40 pg/mL). Regarding the cardiac imaging findings, a total of 14 (32%) patients presented cardiac tissue feature abnormalities, and a total of 9 (20%) patients had a myocarditis-like injury based on cardiac MRI 2018 Lake Louise criteria. When we further assessed the T1 and T2 mapping values for of patients' individual, abnormal raised global native T1, T2, and extracellular volume were seen in 6 (14%), 6 (14%), and 4 (9%) patients, respectively. Comparing with controls, the patients had lower LV global longitudinal strain and (-22.2 ± 2.8% vs. -24.6 ± 2.0%, P < 0.001) and global circumferential strain (-20.7 ± 6.8% vs. -24.3 ± 2.9%, P = 0.014), but higher global native T1 (1318.8 ± 55.5 ms vs. 1282.9 ± 38.1 ms, P = 0.006). Four (9%) patients presented myocardial late gadolinium enhancement with subepicardial pattern mostly common seen, and two (5%) patients presented pericardial enhancement. CONCLUSIONS: The cardiac MRI could detect subclinical functional and myocardial tissue characteristic abnormalities in individuals who were recovering from Delta Variant without cardiac-related clinical findings. The native T1 mapping and strain imaging may be a sensitive tool for the noninvasive detection of a subset of patients who are at risk for cardiac sequelae and more prone to myocardial damage in survivors with Delta Variant.

Berbamine hydrochloride potently inhibits SARS-CoV-2 infection by blocking S protein-mediated membrane fusion.

COVID-19 caused by SARS-CoV-2 has posed a significant threat to global public health since its outbreak in late 2019. Although there are a few drugs approved for clinical treatment to combat SARS-CoV-2 infection currently, the severity of the ongoing global pandemic still urges the efforts to discover new antiviral compounds. As the viral spike (S) protein plays a key role in mediating virus entry, it becomes a potential target for the design of antiviral drugs against COVID-19. Here, we tested the antiviral activity of berbamine hydrochloride, a bis-benzylisoquinoline alkaloid, against SARS-CoV-2 infection. We found that berbamine hydrochloride could efficiently inhibit SARS-CoV-2 infection in different cell lines. Further experiments showed berbamine hydrochloride inhibits SARS-CoV-2 infection by targeting the viral entry into host cells. Moreover, berbamine hydrochloride and other bis-benzylisoquinoline alkaloids could potently inhibit S-mediated cell-cell fusion. Furthermore, molecular docking results implied that the berbamine hydrochloride could bind to the post fusion core of SARS-CoV-2 S2 subunit. Therefore, berbamine hydrochloride may represent a potential efficient antiviral agent against SARS-CoV-2 infection.

A new screening system for entry inhibitors based on cell-to-cell transmitted syncytia formation mediated by self-propagating hybrid VEEV-SARS-CoV-2 replicon.

The extremely high transmission rate of SARS-CoV-2 and severe cases of COVID-19 pose the two critical challenges in the battle against COVID-19. Increasing evidence has shown that the viral spike (S) protein-driven syncytia may be responsible for these two events. Intensive attention has thus been devoted to seeking S-guided syncytium inhibitors. However, the current screening campaigns mainly rely on either live virus-based or plasmid-based method, which are always greatly limited by the shortage of high-level biosafety BSL-3 facilities or too much labour-intensive work. Here, we constructed a new hybrid VEEV-SARS-CoV-2-S-eGFP reporter vector through replacement of the structural genes of Venezuelan equine encephalitis virus (VEEV) with the S protein of SARS-CoV-2 as the single structural protein. VEEV-SARS-CoV-2-S-eGFP can propagate steadily through cell-to-cell transmission pathway in S- and ACE2-dependent manner, forming GFP positive syncytia. In addition, a significant dose-dependent decay in GFP signals was observed in VEEV-SARS-CoV-2-S-eGFP replicating cells upon treatment with SARS-CoV-2 antiserum or entry inhibitors, providing further evidence that VEEV-SARS-CoV-2-S-eGFP system is highly sensitive to characterize the anti-syncytium-formation activity of antiviral agents. More importantly, the assay is able to be performed in a BSL-2 laboratory without manipulation of live SARS-CoV-2. Taken together, our work establishes a more convenient and efficient VEEV-SARS-CoV-2-S-eGFP replicating cells-based method for rapid screening of inhibitors blocking syncytium formation.

The Implementation of Patient-Centered Humanistic Care for COVID-19 Closely Contacted Hemodialysis Patients Under the Hospital-Based Group Medical Quarantine: A Brief Research Report.

In February 2020, an inpatient in Peking University People's Hospital (PKUPH), China, was confirmed positive for the novel coronavirus. In this case, 143 hemodialysis patients were labeled as close contacts and required to be placed under the hospital-based group medical quarantine (HB-GMQ) for 2 weeks by the authorities. After the case was reported, false or misleading information about the case flourished on social media platforms, which led to infodemic. Under this context, PKUPH adopted patient-centered humanistic care to implement the HB-GMQ, through the synergy of administrative, healthcare, logistical, and other measures under the model of patient-centered care of the Massachusetts Medical Society (MMS). As a result, all the patients tided over the HB-GMQ with no COVID-19 infection and no unanticipated adverse events, and all met the criteria for lifting the HB-GMQ. According to the questionnaires taken during the HB-GMQ, a high level of satisfaction was found among the quarantined and no symptomatic increase of anxiety and depression in the patients before and during the HB-GMQ, by comparing the Zung self-rating anxiety scale (SAS) and self-rating depression scale (SDS) conducted in December 2019 and on the 12th day of the HB-GMQ. This article is to brief on PKUPH's experience in implementing patient-centered humanistic care tailored to hemodialysis patients under the HB-GMQ, and to validate the hypothesis that patient-centered humanistic care is effective and helpful to help them tide over the HB-GMQ, so as to shed light on how to implement the HB-GMQ and cope with the HB-GMQ-induced problems in other hospitals.

Intranasal delivery of replicating mRNA encoding neutralizing antibody against SARS-CoV-2 infection in mice.

The lung is the prophylaxis target against SARS-CoV-2 infection, and neutralizing antibodies are a leading class of biological products against various infectious viral pathogen. In this study, we develop a safe and cost-effective platform to express neutralizing antibody in the lung with replicating mRNA basing on alphavirus replicon particle (VRP) delivery system, to prevent SARS-CoV-2 infections. First, a modified VEEV replicon with two subgenomic (sg) promoters was engineered to translate the light and heavy chains of antibody simultaneously, for expression and assembly of neutralizing anti-SARS-CoV-2 antibody CB6. Second, the feasibility and protective efficacy of replicating mRNA against SARS-CoV-2 infection were demonstrated through both in vitro and in vivo assays. The lung target delivery with the help of VRP system resulted in efficiently block SARS-CoV-2 infection with reducing viral titer and less tissue damage in the lung of mice. Overall, our data suggests that expressing neutralizing antibodies in the lungs with the help of self-replicating mRNA could potentially be a promising prophylaxis approach against SARS-CoV-2 infection.

Ultrasensitive detection of SARS-CoV-2 spike protein in untreated saliva using SERS-based biosensor.

Early diagnosis and monitoring of SARS-CoV-2 virus is essential to control COVID-19 outbreak. In this study, we propose a promising surface enhanced Raman scattering (SERS)-based COVID-19 biosensor for ultrasensitive detection of SARS-CoV-2 virus in untreated saliva. The SERS-immune substrate was fabricated by a novel oil/water/oil (O/W/O) three-phase liquid-liquid interfaces self-assembly method, forming two layers of dense and uniform gold nanoparticle films to ensure the reproducibility and sensitivity of SERS immunoassay. The detection was performed by an immunoreaction between the SARS-CoV-2 spike antibody modified SERS-immune substrate, spike antigen protein and Raman reporter-labeled immuno-Ag nanoparticles. This SERS-based biosensor was able to detect the SARS-CoV-2 spike protein at concentrations of 0.77 fg mL-1 in phosphate-buffered saline and 6.07 fg mL-1 in untreated saliva. The designed SERS-based biosensor exhibited excellent specificity and sensitivity for SARS-CoV-2 virus without any sample pretreatment, providing a potential choice for the early diagnosis of COVID-19.

SARS-CoV-2 replicon for high-throughput antiviral screening.

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus, which is highly pathogenic and classified as a biosafety level 3 (BSL-3) agent, has greatly threatened global health and efficacious antivirals are urgently needed. The high requirement of facilities to manipulate the live virus has limited the development of antiviral study. Here, we constructed a reporter replicon of SARS-CoV-2, which can be handled in a BSL-2 laboratory. The Renilla luciferase activity effectively reflected the transcription and replication levels of the replicon genome. We identified the suitability of the replicon in antiviral screening using the known inhibitors, and thus established the replicon-based high-throughput screening (HTS) assay for SARS-CoV-2. The application of the HTS assay was further validated using a few hit natural compounds, which were screened out in a SARS-CoV-2 induced cytopathic-effect-based HTS assay in our previous study. This replicon-based HTS assay will be a safe platform for SARS-CoV-2 antiviral screening in a BSL-2 laboratory without the live virus.

Deficiencies in Planning Interventional Trial Registration of COVID-19 in China.

Background: The coronavirus disease 2019 (COVID-19) pandemic has affected the world since late 2019. The efforts to control the spread of the virus need to be supported by credible evidence. Therefore, we analyzed the rationality of the timeline and geographic distribution of COVID-19 trial registration in mainland China. Methods: We searched the Chinese Clinical Trial Registry (ChiCTR, http://www.chictr.org.cn/) and International Clinical Trials Registry Platform (ICTRP, https://www.who.int/ictrp/en/) using keywords including novel coronavirus, coronavirus pneumonia, 2019-nCoV, COVID-19, and SARS-COV-2 from 1 December 2019 to 27 April 2020 and included interventional randomized and non-randomized trials including patients with confirmed cases of COVID-19 in mainland China. The registered trials were reviewed, and data were independently extracted by two reviewers based on the inclusion criteria. Results: A total of 263 registered interventional trials were included in the study. We defined the sample size index (SI) as the total number of patients needed by the trials divided by the total number of patients diagnosed with COVID-19. A total of 84,341 patients had been diagnosed with COVID-19 in China as of 26 April 2020, and the included trials had a combined sample size of 31,156 patients (SI: 0.37). After control of the COVID-19 epidemic was achieved in China (February 18, 2020), the SI was 1.54, suggesting that the number of patients needed by the trials was greater than the number of newly diagnosed patients. The SIs in 8 out of 26 provinces in mainland China were >1. Conclusions: Our results suggested a clear over registration of COVID-19 trials in China, especially after control of the pandemic was achieved, preventing the generation of high-quality evidence.

Nucleic acid detection analysis of 71 cases of COVID-19 with biological samples of diferent disease course

Objective: To study the nucleic acid detection results of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) in different biological samples of COVID-19 (coronavirus disease 2019, COVID-19) patients in different stages, and we analyze the results and clinical significance.