Treatment Strategies For COVID-19 Research Articles

Identification of potent COVID-19 main protease inhibitors by loading of favipiravir on Mg12O12 and Zn12O12 nanoclusters: an in silico strategy for COVID-19 treatment

Pandemic new severe acute respiratory syndrome coronavirus (SARS-CoV-2) virus has increased throughout the world. There is no effective treatment against this virus until now. Since its appearance in Wuhan, China in December 2019, SARS-CoV-2 becomes the largest challenge the world is opposite today, including the discovery of an antiviral drug for this virus. Several viral proteins have been prioritized as SARS-CoV-2 antiviral drug targets, among them the papain-like protease (PLpro) and the main protease (Mpro). Inhibition of these proteases would target viral replication, viral maturation and suppression of host innate immune responses. Potential candidates have been identified to show inhibitory effects against Mpro, both in biochemical assays and viral replication in cells. There are different molecules such as lopinavir and favipiravir considerably inhibit the activity of Mpro in vitro. Different studies have shown that structurally improved favipiravir and other similar compounds can inhibit SARS-CoV-2 main protease. In this work, we study the interactions between favipiravir with Mg12O12 and Zn12O12 nanoclusters by density functional theory (DFT) and quantum mechanics atoms in molecules (QMAIM) methods to summarize the ability to load favipiravir onto Mg12O12 and Zn12O12 nanoclusters. Favipiravir-Mg12O12 and favipiravir-Zn12O12 lowest structures complexes were chosen to dock inside the SARS-CoV-2 main protease by molecular docking study. The molecular docking analysis revealed that the binding affinity of Mg12O12 and Zn12O12 nanoclusters inside the Mpro receptor is larger than that of favipiravir. Also, the loading of favipiravir on the surface of Mg12O12 and Zn12O12 nanoclusters increased the binding affinity against the Mpro receptor. Subsequently, 100 ns molecular dynamics simulation of the favipiravir-Mg12O12, and favipiravir-Zn12O12 docked inside the Mpro complexes established that favipiravir-Mg12O12, forms the most stable complex with the Mpro. Further molecular mechanics Poisson Boltzmann surface area (MMPBSA) analyses using the MD trajectories also demonstrated the higher binding affinity of favipiravir-Mg12O12 inside the Mpro. In summary, this study demonstrates a new way to characterize leads for novel anti-viral drugs against SARS-CoV-2, by improving the drug ability of favipiravir via loading it on Mg12O12 and Zn12O12 nanoclusters. Communicated by Ramaswamy H. Sarma

Inhibition of p38 signaling curtails the SARS-CoV-2 induced inflammatory response but retains the IFN-dependent antiviral defense of the lung epithelial barrier

SARS-CoV-2 is the causative agent of the immune response-driven disease COVID-19 for which new antiviral and anti-inflammatory treatments are urgently needed to reduce recovery time, risk of death and long COVID development. Here, we demonstrate that the immunoregulatory kinase p38 MAPK is activated during viral entry, mediated by the viral spike protein, and drives the harmful virus-induced inflammatory responses. Using primary human lung explants and lung epithelial organoids, we demonstrate that targeting p38 signal transduction with the selective and clinically pre-evaluated inhibitors PH-797804 and VX-702 markedly reduced the expression of the pro-inflammatory cytokines IL6, CXCL8, CXCL10 and TNF-α during infection, while viral replication and the interferon-mediated antiviral response of the lung epithelial barrier were largely maintained. Furthermore, our results reveal a high level of drug synergism of both p38 inhibitors in co-treatments with the nucleoside analogs Remdesivir and Molnupiravir to suppress viral replication of the SARS-CoV-2 variants of concern, revealing an exciting and novel mode of synergistic action of p38 inhibition. These results open new avenues for the improvement of the current treatment strategies for COVID-19.

A Systematic Literature Review and Bibliometric Analysis of Ophthalmology and COVID-19 Research.

This review is proposed to summarize the updates on COVID-19 and ophthalmology along with the bibliometric features of articles that have been published since the beginning of the COVID-19 outbreak. The databases, including PubMed, Scopus, and Web of Science, were searched using “Coronavirus,” “COVID-19,” “SARS-CoV-2,” “pandemic,” “ophthalmology,” “ophthalmic,” and “eye” keywords. All published articles except commentaries, errata, and corrigenda up to April 2021 were included. Titles and abstracts were screened, and ophthalmology-focused articles were collected. The bibliographic information of the articles, such as the name and country of the first author, type of study, date of publication, language, and journal name, were extracted. Included studies were assessed using the Joanna Briggs Institute (JBI) critical appraisal checklist. After systematic searching, 2,669 distinct articles were screened by title/abstract, and 1,174 ophthalmology-focused articles were selected to be reviewed. Ophthalmology-focused publications accounted for less than 0.5 percent of the total COVID-19-related articles. Most of the articles were published in the Indian Journal of Ophthalmology, and the main publication type was “original article.” Almost 88% of the publications were in English. There was a decline in the publication rate during the initial months of 2021 compared with the middle and last months of 2020. Most of the publications were affiliated with the United States of America. However, Singapore and the United Kingdom were the countries with the highest number of publications after population adjustment. Furthermore, a comprehensive review on major topics including SARS-CoV-2 ocular tropism, ophthalmic manifestations, ocular complications due to COVID-19 treatment strategies, the pandemic effect on ophthalmology care and operations, myopia progression during the pandemic, and telemedicine was conducted.

Molecular and Clinical Investigation of COVID-19: From Pathogenesis and Immune Responses to Novel Diagnosis and Treatment.

The coronavirus-related severe acute respiratory syndrome (SARS-CoV) in 2002/2003, the Middle East respiratory syndrome (MERS-CoV) in 2012/2013, and especially the current 2019/2021 severe acute respiratory syndrome-2 (SARS-CoV-2) negatively affected the national health systems worldwide. Different SARS-CoV-2 variants, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), and recently Omicron (B.1.1.529), have emerged resulting from the high rate of genetic recombination and S1-RBD/S2 mutation/deletion in the spike protein that has an impact on the virus activity. Furthermore, genetic variability in certain genes involved in the immune system might impact the level of SARS-CoV-2 recognition and immune response against the virus among different populations. Understanding the molecular mechanism and function of SARS-CoV-2 variants and their different epidemiological outcomes is a key step for effective COVID-19 treatment strategies, including antiviral drug development and vaccine designs, which can immunize people with genetic variabilities against various strains of SARS-CoV-2. In this review, we center our focus on the recent and up-to-date knowledge on SARS-CoV-2 (Alpha to Omicron) origin and evolution, structure, genetic diversity, route of transmission, pathogenesis, new diagnostic, and treatment strategies, as well as the psychological and economic impact of COVID-19 pandemic on individuals and their lives around the world.

The Cytokine Storm in COVID-19: The Strongest Link to Morbidity and Mortality in the Current Epidemic

COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. The clinical presentations of the SARS-CoV-2 infection are widely variable and treatment strategies for COVID-19 are dependent on the infection phase. Timing the right treatment for the right phase of this disease is paramount, with correlations detected between the phase of the infection and the type of drug used to treat. The immune system activation following COVID-19 infection can further develop to a fulminant cytokine storm which can progress to acute respiratory distress syndrome. The inflammatory phase, or the hyperinflammation phase, is a later stage when patients develop acute respiratory distress syndrome (ARDS), sepsis, and kidney and other organ failure. In this stage, the virus is probably not necessary and all the damage is due to the immune system’s cytokine storm. Immunosuppressive or immunomodulatory agent administration is the major strategy in treating COVID-19 patients at this stage. On the other hand, immunodeficient patients who are treated with immunomodulator agents have attenuated immune systems that do not produce enough cytokines. Current data do not show an increased risk of severe COVID-19 in patients taking biologic therapies or targeted disease-modifying antirheumatic drugs. However, more comprehensive studies are needed to assess the effect of these medications, and whether they may actually be protective of the severe type of disease. Although medications for COVID-19 and for the cytokine storm are important, the main breakthrough in slowing down the pandemic was developing effective vaccines. These vaccines showed a dramatic result in reducing morbidity and mortality up to the Delta variant’s spread. However, the emergence of the new variant, Omicron, influenced the successful results we had before. This variant is more contagious but less dangerous than Delta. The aim now is to develop vaccines based on the Omicron and Delta immunogens in the future for broad protection against different variants.

SARS-CoV-2 Infection, Sex-Related Differences, and a Possible Personalized Treatment Approach with Valproic Acid: A Review.

Sex differences identified in the COVID-19 pandemic are necessary to study. It is essential to investigate the efficacy of the drugs in clinical trials for the treatment of COVID-19, and to analyse the sex-related beneficial and adverse effects. The histone deacetylase inhibitor valproic acid (VPA) is a potential drug that could be adapted to prevent the progression and complications of SARS-CoV-2 infection. VPA has a history of research in the treatment of various viral infections. This article reviews the preclinical data, showing that the pharmacological impact of VPA may apply to COVID-19 pathogenetic mechanisms. VPA inhibits SARS-CoV-2 virus entry, suppresses the pro-inflammatory immune cell and cytokine response to infection, and reduces inflammatory tissue and organ damage by mechanisms that may appear to be sex-related. The antithrombotic, antiplatelet, anti-inflammatory, immunomodulatory, glucose- and testosterone-lowering in blood serum effects of VPA suggest that the drug could be promising for therapy of COVID-19. Sex-related differences in the efficacy of VPA treatment may be significant in developing a personalised treatment strategy for COVID-19.

Anti-inflammatory response of cardamom extract and prediction of therapeutic window in COVID-19 patients by assessing inflammatory markers using RT-PCR.

IntroductionMolecular diagnostics using RT-PCR has now emerged as the new diagnostic method for clinicians with the dawn of SARS-CoV-2. In India, the popularity and awareness of RT-PCR and particularly the increased availability of testing machines across hospitals has now opened up possibilities of diagnostic tests with RT-PCR. In view of the cytokine storm which is the significant reason for morbidity and mortality of COVID-19 patients, we proposed to test the usefulness of a multiplex RT-PCR test kit that simultaneously measured inflammatory markers namely, IL-6, TNF– α and IL-10 (IFM) all in one tube. The study included a group of patients who were equally allotted to two treatment arms one of which received standard of care along with a food supplement capsule as a natural anti-inflammatory (RECOVEREEZ FORTE™), and the other group received standard of care that included oral Prednisolone tablets in tapered dosage. RECOVEREEZ FORTE™ consists of potent biomolecules from cardamom extract. A natural product with substantial anti-inflammatory action when consumed early at the onset of symptoms is hereby proven by comparing gene expression profile of inflammatory markers with routinely tested inflammatory parameters such as serum IL-6, CRP and LDH. In addition to predicting worse disease outcomes beforehand, RT-PCR assay tests provides an opportunity for identifying therapeutic window aiding in practicing effective treatment strategy for COVID-19. RT-PCR analysis of IFM together being used in a single multiplex kit is being first reported and such a test as a prognosticator for disease progression does seem promising and worthy of clinicians adopting novel testing modalities in clinical practice.Aim of the studyTo study the anti-inflammatory response of RECOVEREEZ FORTE™ using RT-PCR based multiplex gene profiling of inflammatory markers in disease prognosis and show its predictability of worsening outcomes and its role in identifying therapeutic window for RECOVEREEZ FORTE™. To show the potentiality of RECOVEREEZ FORTE™ in reducing COVID-19 symptoms and SARS-CoV-2 RT-PCR Ct values of the treatment group.Materials and methodsThis was a short study of a 10-day period where the end point was the negativity of COVID-19 on RT-PCR test or the decline in cycle threshold (Ct) values of the test performed on day 10 when compared to day 0. During the course of the study, patients were given standard treatment and an oral dose of 500 mg of RECOVEREEZ FORTE™ thrice daily, or standard of care and oral Prednisolone in tapered dosage (control group). All essential interventions were included in the standard of care as decided by the attending physician. The RT-PCR results of inflammatory markers were compared to routinely tested parameters such as IL-6, CRP and LDH. Time to clinical improvement was in terms of SARS-CoV-2 RT-PCR test negativity or recovery of COVID-19 symptoms. We enrolled 64 patients, of which 32 were allocated to RECOVEREEZ FORTE ™ group and 32 to the control group.ResultsThe RT-PCR analysis of elevated IFM on day 0 corresponded to above normal protein levels of routinely tested parameters such as serum IL-6, CRP and LDH on day 5. Similarly, elevated IFM on day 5 corresponded to above normal protein levels on day 10. Such an association was equally prevalent in both the control group and RECOVEREEZ FORTE™ group, stipulating that RECOVEREEZ FORTE™ may be used as an alternative to steroids. The obtained results indicate that the RT-PCR assessment predicts worse outcomes 5 days earlier. But, the RT-PCR analysis of elevated IFM on day 0 did not correspond to the above normal protein levels of other parameters on day 10. Hence, indicating that the IFM RT-PCR test cannot predict worse outcomes 10 days earlier. Also, RECOVEREEZ FORTE™ when consumed for a period of 10 days normalized LDH values, compared to the control group. Moreover, IFM RT-PCR test identified a 5-day therapeutic window for RECOVEREEZ FORTE™ against inflammation experienced by patients. In addition to the above findings, the authors also observed that majority of the patients belonging to the treatment group showed recovery from symptoms such as fever, cough, sore throat and breathlessness compared to control group by day 5. 12 (37.5%) out of 32 patients and 6 (18.75%) out of 32 patients belonging to the treatment group and control group, respectively, became SARS-CoV-2 negative by day 5, indicating a probable anti-viral action of RECOVEREEZ FORTE™ against SARS-CoV-2.ConclusionThe IFM RT-PCR test possess 5-day early prediction ability and lacks 10-day prediction ability. Treatment with RECOVEREEZ FORTE™ indicates good anti-inflammatory action which is equivalent to steroids. Intake of RECOVEREEZ FORTE ™ for a period of 5 days depicts persistent anti-inflammatory action, recovery of COVID-19 symptoms and a probable anti-viral action. Moreover, an effective normalization of LDH may be rendered by RECOVEREEZ FORTE™ when consumed for a period of 10 days.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10787-022-00951-x.

Investigating the Immunomodulatory Potential of Dental Pulp Stem Cell Cultured on Decellularized Bladder Hydrogel towards Macrophage Response In Vitro.

Mesenchymal stem cells (MSCs) possess immunomodulatory properties and capacity for endogenous regeneration. Therefore, MSC therapy is a promising treatment strategy for COVID-19. However, the cells cannot stay in the lung long enough to exert their function. The extracellular matrix from porcine bladders (B-ECM) has been shown not only to regulate cellular activities but also to possess immunoregulatory characteristics. Therefore, it can be hypothesized that B-ECM hydrogel could be an excellent scaffold for MSCs to grow and could anchor MSCs long enough in the lung so that they can exhibit their immunomodulatory functions. In this study, ECM degradation products and a co-culture system of MSCs and macrophages were developed to study the immunomodulatory properties of ECM and MSCs under septic conditions. The results showed that B-ECM degradation products could decrease pro-inflammatory and increase anti-inflammatory cytokines from macrophages. In an in vivo mimicking co-culture system, MSCs cultured on B-ECM hydrogel exhibited immunomodulatory properties at both gene and protein levels. Both B-ECM degradation products and MSC conditioned medium supported the wound healing of alveolar epithelial cells. The results from the study could offer a basis for investigation of immunomodulation by ECM and MSCs before conducting in vivo experiments, which could later be applied in regenerative medicine.

Drug repurposing for identification of potential spike inhibitors for SARS-CoV-2 using molecular docking and molecular dynamics simulations.

For the last two years, the COVID-19 pandemic has continued to bring consternation on most of the world. According to recent WHO estimates, there have been more than 5.6 million deaths worldwide. The virus continues to evolve all over the world, thus requiring both vigilance and the necessity to find and develop a variety of therapeutic treatments, including the identification of specific antiviral drugs. Multiple studies have confirmed that SARS‐CoV‐2 utilizes its membrane-bound spike protein to recognize human angiotensin-converting enzyme 2 (ACE2). Thus, preventing spike-ACE2 interactions is a potentially viable strategy for COVID-19 treatment as it would block the virus from binding and entering into a host cell. This work aims to identify potential drugs using an in silico approach. Molecular docking was carried out on both approved drugs and substances previously tested in vivo. This step was followed by a more detailed analysis of selected ligands by molecular dynamics simulations to identify the best molecules that thwart the ability of the virus to interact with the ACE2 receptor. Because the SARS-CoV-2 virus evolves rapidly due to a plethora of immunocompromised hosts, the compounds were tested against five different known lineages. As a result, we could identify substances that work well on individual lineages and those showing broader efficacy. The most promising candidates among the currently used drugs were zafirlukast and simeprevir with an average binding affinity of –22 kcal/mol for spike proteins originating from various lineages. The first compound is a leukotriene receptor antagonist that is used to treat asthma, while the latter is a protease inhibitor used for hepatitis C treatment. From among the in vivo tested substances that concurrently exhibit promising free energy of binding and ADME parameters (indicating a possible oral administration) we selected the compound BDBM50136234. In conclusion, these molecules are worth exploring further by in vitro and in vivo studies against SARS-CoV-2.

Investigation Of Lymphocyte Enhancement In Vivo On Honey Intervention: A Systematic Review Study To Overcome Early Lymphopenia In Covid-19

COVID-19 is caused by a coronavirus and was first identified in Wuhan, China. Clinical symptoms of COVID-19 patients show a significant decrease in lymphocytes. Decreased lymphocyte count is a factor that increases severity in COVID-19 disease. COVID-19 patients who died reported a very low number of lymphocytes compared to COVID-19 patients who recovered. Increasing lymphocytes to normal levels again, especially in the initial phases of infection, is one of the keys to healing COVID-19 patients. The immune system can be used as a strategy for COVID-19 treatment. Still, immunomodulators must be given at the right time at the beginning of infection, with the right dose, not to cause deterioration in the patient. Immunomodulator administration in the final stage can cause severity in COVID-19 disease due to increased cytokine storm. Therefore, Immunodulator screening, which increases lymphocyte counts, is essential for COVID-19 treatment strategies in the initial stage. Lymphocytes are easily isolated from human blood and consist of NK (Natural Killer) cells, T cells (for cell-mediated, adaptive cytotoxic immunity), and B cells (for humoral, antibody-driven adaptive immunity). Lymphocytes can be isolated from the blood and cultured in vitro. Animal intervention studies showed that immunomodulatory substances could be used for immunomodulator screening candidates for COVID-19 in initial stage therapy. Some candidates for active ingredients that can be used as immunomodulators are honey. Honey has been shown to increase mouse T cell proliferation. This systematic review shows that honey can increase lymphocyte proliferation and have an anti-inflammatory function by lowering IL-6 levels in several in vivo studies.

450. Type I Interferon Autoantibodies Are Detected in Those with Critical COVID-19, Including a Young Female Patient

BackgroundApproximately 10-20% of patients with critical COVID-19 harbor neutralizing autoantibodies (auto-Abs) that target type I interferons (IFN), a family of cytokines that induce critical innate immune defense mechanisms upon viral infection. Studies to date indicate that these auto-Abs are mostly detected in men over age 65. MethodsWe screened for type I IFN serum auto-Abs in sera collected < 21 days post-symptom onset in a subset of 103 COVID-19 inpatients and 24 outpatients drawn from a large prospective cohort study of SARS-CoV-2 infected patients enrolled across U.S. Military Treatment Facilities. The mean age of this n = 127 subset of study participants was 55.2 years (SD = 15.2 years, range 7.7 – 86.2 years), and 86/127 (67.7%) were male. ResultsAmong those hospitalized 49/103 (47.6%) had severe COVID-19 (required at least high flow oxygen), and nine subjects died. We detected neutralizing auto-Abs against IFN-α, IFN-ω, or both, in four inpatients (3.9%, 8.2% of severe cases), with no auto-Abs detected in outpatients. Three of these patients were white males over the age of 62, all with multiple comorbidities; two of whom died and the third requiring high flow oxygen therapy. The fourth patient was a 36-year-old Hispanic female with a history of obesity who required mechanical ventilation during her admission for COVID-19.ConclusionThese findings support the association between type I IFN auto-antibody production and life-threatening COVID-19. With further validation, reliable high-throughput screening for type I IFN auto-Abs may inform diagnosis, pathogenesis and treatment strategies for COVID-19, particularly in older males. Our finding of type I IFN auto-Ab production in a younger female prompts further study of this autoimmune phenotype in a broader population. Disclosures David A. Lindholm, MD, American Board of Internal Medicine (Individual(s) Involved: Self): Member of Auxiliary R&D Infectious Disease Item-Writer Task Force. No financial support received. No exam questions will be disclosed ., Other Financial or Material Support David Tribble, M.D., DrPH, Astra Zeneca (Other Financial or Material Support, HJF, in support of USU IDCRP, funded under a CRADA to augment the conduct of an unrelated Phase III COVID-19 vaccine trial sponsored by AstraZeneca as part of USG response (unrelated work)) Simon Pollett, MBBS, Astra Zeneca (Other Financial or Material Support, HJF, in support of USU IDCRP, funded under a CRADA to augment the conduct of an unrelated Phase III COVID-19 vaccine trial sponsored by AstraZeneca as part of USG response (unrelated work))

Highly Specific Sigma Receptor Ligands Exhibit Anti-Viral Properties in SARS-CoV-2 Infected Cells.

(1) Background: There is a strong need for prevention and treatment strategies for COVID-19 that are not impacted by SARS-CoV-2 mutations emerging in variants of concern. After virus infection, host ER resident sigma receptors form direct interactions with non-structural SARS-CoV-2 proteins present in the replication complex. (2) Methods: In this work, highly specific sigma receptor ligands were investigated for their ability to inhibit both SARS-CoV-2 genome replication and virus induced cellular toxicity. This study found antiviral activity associated with agonism of the sigma-1 receptor (e.g., SA4503), ligation of the sigma-2 receptor (e.g., CM398), and a combination of the two pathways (e.g., AZ66). (3) Results: Intermolecular contacts between these ligands and sigma receptors were identified by structural modeling. (4) Conclusions: Sigma receptor ligands and drugs with off-target sigma receptor binding characteristics were effective at inhibiting SARS-CoV-2 infection in primate and human cells, representing a potential therapeutic avenue for COVID-19 prevention and treatment.

COMPARATIVE THEORETICAL ANALYSIS ON RESPIRATORY TRACT INFECTION CAUSED BY DIFFERENT MICROORGANISMS WITH REFERENCE TO COVID-19

Respiratory Tract Infection (RTI) may be caused by different microorganisms and resulting deadly diseases such as novel coronavirus (Covid-19), severe acute respiratory syndrome (SARS), Middle East Respiratory Syndrome (MERS), influenza and other viral infection, tuberculosis, pneumonia 8 other Bacterial RTI etc. Till now there is no recommended treatment strategy for COVID-19, as for this no specific pharmacologically proved drug till invented or identified. To identify/find out any new drug to treat particularly Covid-19 demands detailed attention in the characteristics of virus, so that the specific chemical approach in a short time can solve the health problem arouse worldwide. This paper is highlighting the comparative theoretical analysis of RTI caused by different microorganisms for the purpose of designing antiviral drugs to combat Covid-19.

Natural biflavones are potent inhibitors against SARS-CoV-2 papain-like protease

Papain-like protease (PLpro) is a key enzyme encoded by SARS-CoV-2 that is essential for viral replication and immune evasion. Significant suppression of viral spread and promotion of antiviral immunity can be achieved by inhibition of PLpro, revealing an inspiring strategy for COVID-19 treatment. This study aimed to discover PLpro inhibitors by investigating the national compound library of traditional Chinese medicines (NCLTCMs), a phytochemical library comprising over 9000 TCM-derived compounds. Through virtual screening and enzymatic evaluations, nine natural biflavones were confirmed to be effective PLpro inhibitors with IC50 values ranging from 9.5 to 43.2 μM. Pro-ISG15 cleavage assays further demonstrated that several biflavones exhibited potent inhibitory effects against PLpro-mediated deISGylation, a key process involved in viral immune evasion. Herein, we report the discovery, antiviral evaluation, structure-activity relationship elucidation and molecular docking investigation of biflavones as potent inhibitors of SARS-CoV-2 PLpro.

Disinformation about COVID-19 Preventions and Treatments: Analysis of USFDA Warning Letters

ABSTRACT COVID-19 poses a challenge beyond the virus itself, in that lockdown has been associated increased use of the internet and social media. Disinformation about prevention and treatment strategies for COVID-19 can have lethal consequences. The United States Food and Drug Administration (USFDA) is currently monitoring the compliance of manufacturing firms as well as medicinal product advertisers to the Federal Food, Drug, and Cosmetic Act, 21 USC § 321(h) regulations. In the event of noncompliance in the form of advertising products without prior USFDA approval for specific indications, doses, or route of administration, warning letters (WLs) are issued. WLs are intended to address the concerns identified by USFDA and encourage the recipient to take corrective steps to avoid similar instances in the future. We analyzed 182 WLs that were issued for noncompliance with drugs/devices related to either treatment, prevention, or testing of COVID-19 infections. The medicinal product website was identified as the major source of disinformation, followed by disseminated information on Facebook, Twitter, and Instagram. Nearly four-fifths were related to drugs, followed by devices and biologicals. Several biologicals, as well as allopathic, herbal, and non-herbal drugs were identified in the WLs. We observed that noncompliance with the USFDA regulations in terms of advertising a variety of products for prevention and treatment of COVID-19 infection was widely prevalent. More efforts are required by the respective national drug regulatory authorities to initiate or continue their monitoring of disinformation that may have lethal consequences.

Abstract 111: Vein-Chip Is A New Experimental Model To Predict Pathophysiology Of SARS-CoV-2 Induced Thrombosis

There is a serious limitation of experimental models that can improve our limited knowledge of the mechanisms that regulate endotheliopathy and venous thrombosis (VT) clinically observed frequently amongst the most severe COVID-19 patients. Also, while observation and study of VT in humans are difficult due to the deep-lying nature of the deep veins in which VT develops, lab animal models do not include the venous valves, which are the sites for thrombus development in humans. We develop a Vein-chip microfluidic platform that includes venous valve architecture, endothelial cells (ECs), and whole blood flow, which can include the three factors of Virchow’s triad - endothelial inflammation, stasis of blood flow, and coagulable nature of blood. Our in silico and in vitro observations with Vein-Chip reveal that incompetent valves and thrombosis changes the blood flow pattern in and around the venous valves. We show that healthy endothelium at the venous valve cusps adapt to the complex flow patterns and have an anti-thrombotic phenotype compared to the venous lumen. But exposure of the lumen to living and replicating SARS-CoV-2 virus and inflammatory cytokines found in COVID-19 patient samples inflames the lumen and the valve endothelium becomes pro-thrombotic. Interestingly, when we directed our investigation to analyze the ACE2 expression on these cells, as ACE2 is the functional receptor of the SARS-CoV-2 virus, we found that ACE2 expression was poor under a static culture, but increased dramatically when venous ECs were exposed to shear stress within the vein-chip. This data supports our hypothesis that ACE2 expression (and therefore, SARS-CoV-2 entry into the endothelium) is dependent on venous hemodynamics and the Vein-Chip model is a highly dissectible platform that will help us to unravel the molecular mechanisms that lead to VT and its treatment strategies for COVID-19 and beyond.

Therapeutic supplementation with zinc in the management of COVID-19-related diarrhea and ageusia/dysgeusia: mechanisms and clues for a personalized dosage regimen.

Zinc supplementation is indicated for diarrhea and taste disorders, which are both features of COVID-19. Nevertheless, this strategy has not been tested for the treatment of these secondary complications in the current pandemic. Through an updated review, a practical appraisal was considered as a means of providing a medical nexus of therapeutic zinc regimens as an adjunct in the management of COVID-19–related diarrhea and ageusia/dysgeusia. While diarrhea and taste disorders are consequences of COVID-19, zinc supplementation is useful for non–COVID-19 patients with these clinical problems. The overwhelming evidence for supplementing with zinc in diarrhea and pneumonia is associated with the treatment of children, while for taste disorders the use of supplementing with zinc is more examined in adults. Whereas COVID-19 is more prevalent in adults, precautions should be exercised not to translate the zinc dosage used for children with diarrhea and taste disorders into the current pandemic. Therapeutic doses of zinc used for adults (∼50–150 mg/day of elemental zinc) could be included in the treatment strategies for COVID-19, but this proposal should be examined through randomized studies.

Altered oral and gut microbiota and its association with SARS-CoV-2 viral load in COVID-19 patients during hospitalization

The human oral and gut commensal microbes play vital roles in the development and maintenance of immune homeostasis, while its association with susceptibility and severity of SARS-CoV-2 infection is barely understood. In this study, we investigated the dynamics of the oral and intestinal flora before and after the clearance of SARS-CoV-2 in 53 COVID-19 patients, and then examined their microbiome alterations in comparison to 76 healthy individuals. A total of 140 throat swab samples and 81 fecal samples from these COVID-19 patients during hospitalization, and 44 throat swab samples and 32 fecal samples from sex and age-matched healthy individuals were collected and then subjected to 16S rRNA sequencing and viral load inspection. We found that SARS-CoV-2 infection was associated with alterations of the microbiome community in patients as indicated by both alpha and beta diversity indexes. Several bacterial taxa were identified related to SARS-CoV-2 infection, wherein elevated Granulicatella and Rothia mucilaginosa were found in both oral and gut microbiome. The SARS-CoV-2 viral load in those samples was also calculated to identify potential dynamics between COVID-19 and the microbiome. These findings provide a meaningful baseline for microbes in the digestive tract of COVID-19 patients and will shed light on new dimensions for disease pathophysiology, potential microbial biomarkers, and treatment strategies for COVID-19.

Renin Angiotensin System Inhibition as treatment for Covid-19?

Renin Angiotensin System Inhibition as treatment for Covid-19?

Distinct clinical and immunological profiles of patients with evidence of SARS-CoV-2 infection in sub-Saharan Africa

Although the COVID-19 pandemic has left no country untouched there has been limited research to understand clinical and immunological responses in African populations. Here we characterise patients hospitalised with suspected (PCR-negative/IgG-positive) or confirmed (PCR-positive) COVID-19, and healthy community controls (PCR-negative/IgG-negative). PCR-positive COVID-19 participants were more likely to receive dexamethasone and a beta-lactam antibiotic, and survive to hospital discharge than PCR-negative/IgG-positive and PCR-negative/IgG-negative participants. PCR-negative/IgG-positive participants exhibited a nasal and systemic cytokine signature analogous to PCR-positive COVID-19 participants, predominated by chemokines and neutrophils and distinct from PCR-negative/IgG-negative participants. PCR-negative/IgG-positive participants had increased propensity for Staphylococcus aureus and Streptococcus pneumoniae colonisation. PCR-negative/IgG-positive individuals with high COVID-19 clinical suspicion had inflammatory profiles analogous to PCR-confirmed disease and potentially represent a target population for COVID-19 treatment strategies.