Antiviral activity of natural phenolic compounds in complex at an allosteric site of SARS-CoV-2 papain-like protease.

SARS-CoV-2 papain-like protease (PLpro) covers multiple functions. Beside the cysteine-protease activity, facilitating cleavage of the viral polypeptide chain, PLpro has the additional and vital function of removing ubiquitin and ISG15 (Interferon-stimulated gene 15) from host-cell proteins to support coronaviruses in evading the host's innate immune responses. We identified three phenolic compounds bound to PLpro, preventing essential molecular interactions to ISG15 by screening a natural compound library. The compounds identified by X-ray screening and complexed to PLpro demonstrate clear inhibition of PLpro in a deISGylation activity assay. Two compounds exhibit distinct antiviral activity in Vero cell line assays and one inhibited a cytopathic effect in non-cytotoxic concentration ranges. In the context of increasing PLpro mutations in the evolving new variants of SARS-CoV-2, the natural compounds we identified may also reinstate the antiviral immune response processes of the host that are down-regulated in COVID-19 infections.

Multi-institutional Analysis of 505 Patients With Coronavirus Disease-2019 Supported With Extracorporeal Membrane Oxygenation: Predictors of Survival.

BACKGROUND: We reviewed our experience with 505 patients with confirmed coronavirus disease-2019 (COVID-19) supported with extracorporeal membrane oxygenation (ECMO) at 45 hospitals and estimated risk factors for mortality. METHODS: A multi-institutional database was created and used to assess all patients with COVID-19 who were supported with ECMO. A Bayesian mixed-effects logistic regression model was estimated to assess the effect on survival of multiple potential risk factors for mortality, including age at cannulation for ECMO as well as days between diagnosis of COVID-19 and intubation and days between intubation and cannulation for ECMO. RESULTS: Median time on ECMO was 18 days (interquartile range, 10-29 days). All 505 patients separated from ECMO: 194 patients (38.4%) survived and 311 patients (61.6%) died. Survival with venovenous ECMO was 184 of 466 patients (39.5%), and survival with venoarterial ECMO was 8 of 30 patients (26.7%). Survivors had lower median age (44 vs 51 years, P < .001) and shorter median time interval from diagnosis to intubation (7 vs 11 days, P = .001). Adjusting for several confounding factors, we estimated that an ECMO patient intubated on day 14 after the diagnosis of COVID-19 vs day 4 had a relative odds of survival of 0.65 (95% credible interval, 0.44-0.96; posterior probability of negative effect, 98.5%). Age was also negatively associated with survival: relative to a 38-year-old patient, we estimated that a 57-year-old patient had a relative odds of survival of 0.43 (95% credible interval, 0.30-0.61; posterior probability of negative effect, >99.99%). CONCLUSIONS: ECMO facilitates salvage and survival of select critically ill patients with COVID-19. Survivors tend to be younger and have shorter time from diagnosis to intubation. Survival of patients supported with only venovenous ECMO was 39.5%.

Extensive Cerebral Venous Sinus Thrombosis (CVST) After the First Dose of Pfizer-BioNTech BNT162b2 mRNA COVID-19 Vaccine without Thrombotic Thrombocytopenia Syndrome (TTS) in a Healthy Woman.

BACKGROUND COVID-19 is an acute respiratory disease caused by the SARS-CoV-2 virus, which was discovered in 2019. The high transmission and seriousness of COVID-19 necessitated the development of an effective vaccine to control spread of the disease. Multiple vaccines have been granted emergency use authorization (EUA) by the U.S. Food and Drug Administration, namely, the Pfizer-BioNTech, Moderna (mRNA), and the Johnson & Johnson/Janssen (vector) vaccines. As these novel vaccines have been used, adverse effects have been reported, ranging from mild myalgia to severe anaphylaxis and thrombotic events. Thrombotic consequences raised suspicion for the development of cerebral venous sinus thrombosis (CVST), which is a severe condition associated with occlusion of venous sinuses and disruption of the venous system flow. CASE REPORT A 28-year-old healthy woman presented with a 2-week history of persistent and progressive headache 4 days after receiving an mRNA COVID-19 vaccine (Pfizer-BioNTech). Cerebral computed tomography (CT) and CT venography confirmed the presence of extensive thrombus involving the left transverse and sigmoid sinus as well as the internal jugular vein. Furthermore, other than recent the COVID-19 vaccination, there were no precipitant risk factors in her clinical history or in the detailed laboratory work-up. CONCLUSIONS Headache associated with red flags following administration of any COVID-19 vaccine should prompt urgent neuroimaging to rule out secondary causes and determine the appropriate management. Our patient lacked the typical profile of CVST commonly seen following administration of the Oxford-Astrazeneca vaccine. The findings of low platelet count may indicate the peculiar pathophysiology of a thrombotic event associated with with the Pfizer vaccine.

SARS-CoV-2 papain-like protease PLpro in complex with natural compounds reveal allosteric sites for antiviral drug design (preprint)

SARS-CoV-2 papain-like protease (PLpro) covers multiple functions. Beside the cysteine-protease activity, PLpro has the additional and vital function of removing ubiquitin and ISG15 (Interferon-stimulated gene 15) from host-cell proteins to aid coronaviruses in evading the hosts innate immune responses. We established a high-throughput X-ray screening to identify inhibitors by elucidating the native PLpro structure refined to 1.42 Angstroms and performing co-crystallization utilizing a diverse library of selected natural compounds. We identified three phenolic compounds as potential inhibitors. Crystal structures of PLpro inhibitor complexes, obtained to resolutions between 1.7-1.9 Angstroms, show that all three compounds bind at the ISG15/Ub-S2 allosteric binding site, preventing the essential ISG15-PLpro molecular interactions. All compounds demonstrate clear inhibition in a deISGylation assay, two exhibit distinct antiviral activity and one inhibited a cytopathic effect in a non-cytotoxic concentration range. These results highlight the druggability of the rarely explored ISG15/Ub-S2 PLpro allosteric binding site to identify new and effective antiviral compounds. Importantly, in the context of increasing PLpro mutations in the evolving new variants of SARS-CoV-2, the natural compounds we identified may also reinstate the antiviral immune response processes of the host that are down-regulated in COVID-19 infections.

Multi-institutional Analysis of 100 Consecutive Patients with COVID-19 and Severe Pulmonary Compromise Treated with Extracorporeal Membrane Oxygenation: Outcomes and Trends Over Time.

The role of extracorporeal membrane oxygenation (ECMO) in the management of severely ill patients with coronavirus disease 2019 (COVID-19) continues to evolve. The purpose of this study is to review a multi-institutional clinical experience in 100 consecutive patients, at 20 hospitals, with confirmed COVID-19 supported with ECMO. This analysis includes our first 100 patients with complete data who had confirmed COVID-19 and were supported with ECMO. The first patient in the cohort was placed on ECMO on March 17, 2020. Differences by the mortality group were assessed using χ2 tests for categorical variables and Kruskal-Wallis rank-sum tests and Welch's analysis of variance for continuous variables. The median time on ECMO was 12.0 days (IQR = 8-22 days). All 100 patients have since been separated from ECMO: 50 patients survived and 50 patients died. The rate of survival with veno-venous ECMO was 49 of 96 patients (51%), whereas that with veno-arterial ECMO was 1 of 4 patients (25%). Of 50 survivors, 49 have been discharged from the hospital and 1 remains hospitalized at the ECMO-providing hospital. Survivors were generally younger, with a lower median age (47 versus 56.5 years, p = 0.014). In the 50 surviving patients, adjunctive therapies while on ECMO included intravenous steroids (26), anti-interleukin-6 receptor blockers (26), convalescent plasma (22), remdesivir (21), hydroxychloroquine (20), and prostaglandin (15). Extracorporeal membrane oxygenation may facilitate salvage and survival of selected critically ill patients with COVID-19. Survivors tend to be younger. Substantial variation exists in the drug treatment of COVID-19, but ECMO offers a reasonable rescue strategy.

Extracorporeal Membrane Oxygenation in the Treatment of Severe Pulmonary and Cardiac Compromise in Coronavirus Disease 2019: Experience with 32 Patients.

As coronavirus disease 2019 (COVID-19) cases surge worldwide, an urgent need exists to enhance our understanding of the role of extracorporeal membrane oxygenation (ECMO) in the management of severely ill patients with COVID-19 who develop acute respiratory and cardiac compromise refractory to conventional therapy. The purpose of this manuscript is to review our initial clinical experience in 32 patients with confirmed COVID-19 treated with ECMO. A multi-institutional registry and database was created and utilized to assess all patients who were supported with ECMO provided by SpecialtyCare. Data captured included patient characteristics, pre-COVID-19 risk factors and comorbidities, confirmation of COVID-19 diagnosis, features of ECMO support, specific medications utilized to treat COVID-19, and short-term outcomes through hospital discharge. This analysis includes all of our patients with COVID-19 supported with ECMO, with an analytic window starting March 17, 2020, when our first COVID-19 patient was placed on ECMO, and ending April 9, 2020. During the 24 days of this study, 32 consecutive patients with COVID-19 were placed on ECMO at nine different hospitals. As of the time of analysis, 17 remain on ECMO, 10 died before or shortly after decannulation, and five are alive and extubated after removal from ECMO, with one of these five discharged from the hospital. Adjunctive medication in the surviving patients while on ECMO was as follows: four of five survivors received intravenous steroids, three of five survivors received antiviral medications (Remdesivir), two of five survivors were treated with anti-interleukin-6-receptor monoclonal antibodies (Tocilizumab or Sarilumab), and one of five survivors received hydroxychloroquine. Analysis of these 32 COVID-19 patients with severe pulmonary compromise supported with ECMO suggests that ECMO may play a useful role in salvaging select critically ill patients with COVID-19. Additional patient experience and associated clinical and laboratory data must be obtained to further define the optimal role of ECMO in patients with COVID-19 and acute respiratory distress syndrome (ARDS). These initial data may provide useful information to help define the best strategies to care for these challenging patients and may also provide a framework for much-needed future research about the use of ECMO to treat patients with COVID-19.

Catch and kill airborne SARS-CoV-2 to control spread of COVID-19 by a heated air disinfection system (preprint)

Airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via air-conditioning systems poses a significant threat for the continued escalation of the current coronavirus disease (COVID-19) pandemic. Considering that SARS-CoV-2 cannot tolerate temperatures above 70 {degrees}C, here we designed and fabricated efficient air disinfection systems based on heated nickel (Ni) foam to catch and kill SARS-CoV-2. Virus test results revealed that 99.8% of the aerosolized SARS-CoV-2 was caught and killed by a single pass through a Ni-foam-based filter when heated up to 200 {degrees}C. Additionally, the same filter was also used to catch and kill 99.9% of Bacillus anthracis, an airborne spore. This study paves the way for preventing transmission of SARS-CoV-2 and other highly infectious airborne agents in closed environments. One Sentence SummaryHeated Ni-foam filters are capable of effectively catching and killing airborne SARS-CoV-2 and Bacillus anthracis spores.

Real-time tracking and forecasting of the of COVID-19 outbreak in Kuwait: a mathematical modeling study (preprint)

Kuwait has been experiencing a COVID-19 outbreak since the first imported case on Feb 24, 2020. Analysis of data from the early stage of COVID-19 outbreak in Kuwait can provide important information about the potential epidemic and healthcare burdens as well as assist in evaluating the potential impact of various outbreak control measures. Such control measures are essentially implemented to achieve a sufficient reduction in the effective reproduction number during an outbreak. In this study, we use a mathematical modeling framework to simulate the outbreak dynamics of SARS-CoV-2 transmission in Kuwait and forecast the potential burden on the healthcare system. We calibrate the model against daily numbers of detected infection and death cases using a maximum likelihood framework and estimate both the basic and effective reproduction numbers. Our results indicate that the early control measures implemented in Kuwait had the effect of delaying the intensity of the outbreak but were unsuccessful in reducing Rt below 1. This highlights a need for a systematic investigation of the current public health interventions as well as a scientific surveillance tool that is sufficiently sensitive to outbreak temporal dynamics. Meanwhile, the developed model can serve as a public health tool to control the current outbreak and can be used to anticipate effective measures should a second wave re-emerge in Kuwait.