A Review of SARS-CoV-2 and the Ongoing Clinical Trials

The Effect of Prior Use of Statins on the Severity of COVID-19 Disease: A Retrospective Study

It has been suggested that the use of statin pills beforehand could potentially influence the outcomes when individuals are hospitalized with COVID-19. In this study, we investigated how the prior use of statin medication could influence the COVID-19 severity parameters. In this retrospective cohort study, we categorized COVID-19 patients into 2 groups: statin users and non-users. Then, various data including age, gender, the patient's need for ventilation support, the lowest oxygen blood saturation level, the length of hospitalization, receiving remdesivir treatment, and their COVID-19 vaccination status were collected. Out of 168 patients, 62 had taken statin medication before being admitted. Using statins decreased the patient's need for ventilation support, length of hospitalization, ventilation duration, and oxygen saturation level (P < .001). Interaction effect analysis showed that receiving remdesivir statically affected the length of hospitalization, ventilation duration, and oxygen saturation level but did not significantly affect the association between statins and needing to ventilator. The use of statin pills before COVID-19 admission reduced the requirement for ventilator support.

Globally approved vaccines for COVID-19: a systematic review

COVID-19 caused a public health emergency, which instituted a global effort to develop vaccines using different platforms, such as basic types and new-generation vaccines. Considering the importance of vaccination in preventing the severity of infectious diseases and the success in developing and approving vaccines against COVID-19 in record time, it is essential to learn about the characteristics of these vaccines. This study aimed to conduct a structured, systematic review following the PRISMA guideline, to analyze the general characteristics of vaccines approved globally for use against COVID-19. We used the list of approved vaccines available by the WHO as guidance to search for studies in the literature. We searched the terms "SARS-CoV-2 and vaccine and safety and efficacy" in the MEDLINE via PUBMED and Web of Science databases. We conducted the research on both bases, including complete articles published from January 2020 to June 2023. The selection of files occurred between May/2021 and June/2023. Therefore, the paper did not consider articles published after this period or vaccines approved after this moment. This study only included approved vaccines; phase three studies published in English. We found 11 published articles from phase three that met the established criteria. The vaccines included in this study were: Cominarty, mRNA-1273 or Spikevax, Vaxzevria or AZD1222 or Covishield, CoronaVac or PicoVacc, and Ad26.COV2.S, SputnikV or Gam-Covid-Vac, Covaxin, NVX-CoV2373 or Covovax or Nuvaxovid, WIV04 and HB02, CoVLP or Covifenz and Convidecia or Ad5-nCoV. We summarized the main findings of each vaccine, considering the vaccine composition, number of doses, efficacy analyses, and main adverse effects. In general, the vaccines had high efficacy rates and few adverse effects. Efficacy values are important for vaccine approval, but they will not necessarily reflect the real-world impact of vaccination. It was seen that the effectiveness of COV2.S, CoronaVac/PicoVacc, Cominarty, and Covaxin vaccines was lower than the efficacy, whereas, for AZD1222/Vaxzevria/Covishield, the two parameters remained at similar rates. All vaccines evaluated have different compositions, dosages, populations, and study designs. All are effective in at least preventing symptomatic COVID-19, causing mild or moderate adverse effects when present.

Membrane-Active Singlet Oxygen Photogenerators as a Paradigm for Broad-Spectrum Antivirals: The Case of Halogenated (BOron)-DIPYrromethenes

Enveloped viruses, such as flaviviruses and coronaviruses, are pathogens of significant medical concern that cause severe infections in humans. Some photosensitizers are known to possess virucidal activity against enveloped viruses, targeting their lipid bilayer. Here we report a series of halogenated difluoroboron-dipyrromethene (BODIPYs) photosensitizers with strong virus-inactivating activity. Our structure-activity relationship analysis revealed that BODIPY scaffolds with a heavy halogen atom demonstrate significant efficacy against both tick-borne encephalitis virus (TBEV; Flaviviridae family) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; Coronaviridae family) along with high singlet oxygen quantum yields. Moreover, select compounds also inactivated other enveloped viruses, such as herpes simplex virus type 1 and monkeypox virus. The nature and length of the alkyl side chain notably influenced the virus-inactivating activity of BODIPY molecules. Furthermore, molecular dynamics studies highlighted the critical importance of the positioning of the chromophore moiety within the lipid bilayer. As membrane-targeting photosensitizers, BODIPYs interact directly with virus particles, causing damage to the viral envelope membranes. Thus, TBEV pretreated with BODIPY was completely noninfective for lab mice. Consequently, BODIPY-based photosensitizers hold potential either as broad-spectrum virus-inactivating antivirals against a variety of phylogenetically unrelated enveloped viruses or as potent inactivators of viruses for the development of vaccines for preventing life-threatening emerging viral diseases.

A Glimpse for the subsistence from pandemic SARS-CoV-2 infection

COVID-19 is an emerging viral pandemic caused by SARS-CoV-2, which is the causative agent of unprecedented disease-causing public health threats globally. Worldwide, this outbreak is wreaking havoc due to failure in risk assessment regarding the urgency of the pandemic. As per the reports, many secondary complications which include neurological, nephrological, gastrointestinal, cardiovascular, immune, and hepatic abnormalities, are linked with COVID -19 infection which is associated with prominent respiratory disorders including pneumonia. Hindering the initial binding of the virus with Angiotensin-converting enzyme 2 (ACE2) through the spike protein is one potential boulevard of monoclonal antibodies. Although some drug regimens and vaccines have shown safety in trials, none have been entirely successful yet. This review highlights, some of the potential antibodies (tocilizumab, Sarilumab, Avdoralimab, Lenzilumab, Interferon (alfa /beta /gamma)) screened against SARS-CoV-2 and the most promising drugs (Favipiravir, Hydroxychloroquine, Niclosamide, Ribavirin, Baricitinib, Remdesivir, Arbidol Losartan, Ritonavir, Lopinavir, Baloxavir, Nitazoxanide, Camostat) in various stages of development with their synthetic protocol and their clinical projects are discussed to counter COVID -19.

Navigating the COVID-19 Therapeutic Landscape: Unveiling Novel Perspectives on FDA-Approved Medications, Vaccination Targets, and Emerging Novel Strategies

Amidst the ongoing global challenge of the SARS-CoV-2 pandemic, the quest for effective antiviral medications remains paramount. This comprehensive review delves into the dynamic landscape of FDA-approved medications repurposed for COVID-19, categorized as antiviral and non-antiviral agents. Our focus extends beyond conventional narratives, encompassing vaccination targets, repurposing efficacy, clinical studies, innovative treatment modalities, and future outlooks. Unveiling the genomic intricacies of SARS-CoV-2 variants, including the WHO-designated Omicron variant, we explore diverse antiviral categories such as fusion inhibitors, protease inhibitors, transcription inhibitors, neuraminidase inhibitors, nucleoside reverse transcriptase, and non-antiviral interventions like importin α/β1-mediated nuclear import inhibitors, neutralizing antibodies, and convalescent plasma. Notably, Molnupiravir emerges as a pivotal player, now licensed in the UK. This review offers a fresh perspective on the historical evolution of COVID-19 therapeutics, from repurposing endeavors to the latest developments in oral anti-SARS-CoV-2 treatments, ushering in a new era of hope in the battle against the pandemic.

Neutralizing VHH Antibodies Targeting the Spike Protein of PEDV

Porcine epidemic diarrhea virus (PEDV) is a highly contagious coronavirus that infect pigs' intestinal epithelial cells, causing high morbidity and mortality. Due to the rapid mutation of PEDV, vaccine efficacy is uncertain, prompting exploration of alternative treatments. Nanobodies, also known as variable heavy chain domains of heavy chain-only antibodies (VHHs), offer significant potential in biomedical applications due to their small size and high specificity. In this study, yeast two-hybrid technology was employed to screen for eight specific VHH sequences targeting the PEDV S protein from a synthetically constructed nanobody yeast library. The VHH genes were then cloned into expression plasmids for recombinant protein production, and the resulting VHHs (termed PEDV S-VHHs) were purified. Indirect immunofluorescence assay (IFA) and Western blotting analysis confirmed that these VHHs specifically bind to both PEDV and its S protein. Neutralization assays demonstrated that seven PEDV S-VHHs exhibited potent neutralizing activity against PEDV. Additionally, a combination of these seven antibodies showed enhanced antiviral effects. Preliminary predictions were also made regarding the binding sites between these VHHs and PEDV. The PEDV S-VHHs described in this study hold potential as candidates for the prevention and treatment of PEDV infection.

Exploring the binding dynamics of covalent inhibitors within active site of PLpro in SARS-CoV-2

In the global fight against the COVID-19 pandemic caused by the highly transmissible SARS-CoV-2 virus, the search for potent medications is paramount. With a focused investigation on the SARS-CoV-2 papain-like protease (PLpro) as a promising therapeutic target due to its pivotal role in viral replication and immune modulation, the catalytic triad of PLpro comprising Cys111, His272, and Asp286, highlights Cys111 as an intriguing nucleophilic center for potential covalent bonds with ligands. The detailed analysis of the binding site unveils crucial interactions with both hydrophobic and polar residues, demonstrating the structural insights of the cavity and deepening our understanding of its molecular landscape. The sequence of PLpro among variants of concern (Alpha, Beta, Gamma, Delta and Omicron) and the recent variant of interest, JN.1, remains conserved with no mutations at the active site. Moreover, a thorough exploration of apo, non-covalently bound, and covalently bound PLpro conformations exposes significant conformational changes in loop regions, offering invaluable insights into the intricate dynamics of ligand-protein complex formation. Employing strategic in silico medication repurposing, this study swiftly identifies potential molecules for target inhibition. Within the domain of covalent docking studies and molecular dynamics, using reported inhibitors and clinically tested molecules elucidate the formation of stable covalent bonds with the cysteine residue, laying a robust foundation for potential therapeutic applications. These details not only deepen our comprehension of PLpro inhibition but also play a pivotal role in shaping the dynamic landscape of COVID-19 treatment strategies.

Did the COVID-19 Pandemic Affect the Stress Levels among the Mothers of Premature Infants? A Narrative Review of the Present State of Knowledge, Prevention Strategies, and Future Directions

Understanding COVID-19's effects on susceptible populations remains essential for clinical implementations. Our review aimed to examine whether the pandemic significantly impacted the stress levels in the mothers of premature infants in NICUs. The review of the literature from Google Scholar and PubMed resulted in identifying specific stressors such as the disruption of healthcare systems, limited access to neonatal care, uncertainty due to frequent changes in restrictions, the risk of COVID-19 infection, social isolation, and financial stress. While some quantitative studies concerning this topic did not show a significant increase in the perception of stress in this population compared to the pre-pandemic group, various research has indicated that the COVID-19 pandemic may result in enduring impacts on the emotional and neurological development of children. This article demonstrates a correlation between the repercussions of the COVID-19 pandemic and an elevated incidence of depressive symptoms among the mothers of premature infants. Further studies are needed to assess the long-term impact of pandemic-induced stress.

Rapid antigen detection of severe acute respiratory syndrome coronavirus-2 in stray cats: A cross-sectional study

Background and Aim

Although reverse zoonotic transmission events from humans to domestic cats have been described, there is currently little evidence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) circulation in stray cats. Due to the evidence of natural and experimental infections in cats and the capacity to disseminate the virus among them, this study aimed to identify the SARS-CoV-2 antigen in stray cats from the Federal University of Sergipe in Brazil.

Materials and Methods

One hundred twenty six stray cats from the university were screened for SARS-CoV-2 antigens by random sampling. Throat swab samples were tested for the virus using rapid antigen detection tests.

Results

Of the 126 animals tested, 30 (23.60%) were positive for SARS-CoV-2 antigens. To our knowledge, for the first time, this study detected the SARS-CoV-2 antigen in stray cats and confirmed the presence of SARS-CoV-2 infections in Brazil's stray cat population.

Conclusion

The detection of SARS-CoV-2 in stray cats poses a risk for infected and healthy animals and possibly for humans who attend the university daily. As a limitation of the study, the small sample size necessitates caution when interpreting the results. This underscores the need for further research in this area to help control diseases in stray animals during potential pandemics. This highlights the need for monitoring and controlling the spread of the virus in stray animal populations.

Computational design and investigation of the monomeric spike SARS-CoV-2-ferritin nanocage vaccine stability and interactions

Since the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) outbreak, several solutions have been proposed to manage the disease. The most viable option for controlling this virus is to produce effective vaccines. Most of the current SARS-CoV-2 vaccines have focused on the infusion spike protein. Spike exists as a trimer and plays a vital role in infecting host cells by binding to the Angiotensin-Converting Enzyme 2 (ACE2) receptor through its Receptor Binding Domain (RBD). Ferritin protein, a naturally occurring iron-storage protein, has gained attention for vaccine production due to its self-assembling property, non-toxic nature, and biocompatibility. Ferritin nanocages have recently been employed in the development of a SARS-CoV-2 vaccination eliciting not only long-term protective memory cells but also a sustained antibody response. In this study, a combination of in silico investigations including molecular docking, molecular dynamics simulations, and immune simulations were carried out to computationally model the monomeric spike protein on the ferritin nanocage as well as to evaluate its stability and interactions for the first time. The structural dynamics of the modeled complex demonstrated noticeable stability. In particular, the Receptor Binding Domain (RBD) and ferritin within the monomeric spike-ferritin complex illustrated significant stability. The lack of alterations in the secondary structure further supported the overall steadiness of the complex. The decline in the distance between ferritin and spike suggests a strong interaction over time. The cross-correlation matrices revealed that the monomeric spike and ferritin move towards each other supporting the stable interaction between spike and ferritin. Further, the orientation of monomeric spike protein within the ferritin unit facilitated the exposure of critical epitopes, specifically upward active Receptor Binding Domain (RBD), enabling effective interactions with the ACE2 receptor. The immune simulations of the model indicated high-level stimulations of both cellular and humoral immunity in the human body. It was also found that the employed model is effective regardless of the mutated spikes in different variants. These findings shed light on the current status of the SARS-CoV-2-ferritin nanoparticle vaccines and could be used as a framework for other similar vaccine designs.

[The use of immunoglobulins and monoclonal antibodies against COVID-19]

INTRODUCTION

When a new disease occurs, one of the most affordable remedies is drugs containing specific antibodies to this infectious agent. The use of such drugs is aimed at reducing the amount of the pathogen in the macroorganism and the associated reduction in the severity of the symptoms of the disease or recovery. The purpose of this review is to analyze the experience of using immunoglobulins and monoclonal antibodies in the treatment of COVID-19 patients during the pandemic.

RESULTS AND CONCLUSION

The two main groups of medical protective agents that block the penetration of the SARS-CoV-2 virus into permissive cells are drugs obtained from blood plasma of convalescents (immunoglobulin) and human monoclonal antibodies. The first group of drugs in the treatment of COVID-19 includes blood plasma of convalescents, which can be successfully used for emergency prevention. The main disadvantage of using blood plasma convalescents is the difficulty of standardization due to the different content of specific antibodies in donors. Another disadvantage is the undesirable side effects in recipients that occur after plasma administration. An alternative approach to COVID-19 therapy is the use of humanized and genetically engineered human monoclonal antibodies against certain epitopes of the SARS-CoV-2 virus. For example, monoclonal antibodies against receptor-binding domain of the S-protein, which prevents the virus from entering permissive cells and interrupts the development of infection. The advantages of these drugs are their safety, high specific activity, and the possibility of standardization. However, the complexity of their production and high cost make them inaccessible for mass use in practical medicine.

The One Health Concept

The concept of One Health has been developed as the appreciation that human health is intricately connected to those of other animals and the environment that they inhabit. In recent years, the COVID-19 pandemic and noticeable effects of climate change have encouraged national and international cooperation to apply One Health strategies to address key issues of health and welfare. The United Nations (UN) Sustainable Development Goals have established targets for health and wellbeing, clean water and sanitation, climate action, as well as sustainability in marine and terrestrial ecosystems. The One Health Quadripartite comprises the World Health Organization (WHO), the World Organization for Animal Health (WOAH-formerly OIE), the United Nations Food and Agriculture Organization (FAO) and the United Nations Environment Programme (UNEP). There are six areas of focus which are Laboratory services, Control of zoonotic diseases, Neglected tropical diseases, Antimicrobial resistance, Food safety and Environmental health. This article discusses the concept of One Health by considering examples of infectious diseases and environmental issues under each of those six headings. Biomedical Scientists, Clinical Scientists and their colleagues working in diagnostic and research laboratories have a key role to play in applying the One Health approach to key areas of healthcare in the 21st Century.

Clinical Trials of Mesenchymal Stem Cells for the Treatment of COVID 19

Mesenchymal Stem Cells (MSCs) are being investigated as a treatment for a novel viral disease owing to their immunomodulatory, anti-inflammatory, tissue repair and regeneration characteristics, however, the exact processes are unknown. MSC therapy was found to be effective in lowering immune system overactivation and increasing endogenous healing after SARS-CoV-2 infection by improving the pulmonary microenvironment. Many studies on mesenchymal stem cells have been undertaken concurrently, and we may help speed up the effectiveness of these studies by collecting and statistically analyzing data from them. Based on clinical trial information found on clinicaltrials. gov and on 16 November 2020, which includes 63 clinical trials in the field of patient treatment with COVID-19 using MSCs, according to the trend of increasing studies in this field, and with the help of meta-analysis studies, it is possible to hope that the promise of MSCs will one day be realized. The potential therapeutic applications of MSCs for COVID-19 are investigated in this study.

Potential Drugs in COVID-19 Management

The SARS-CoV-2 virus first emerged in China in December 2019 and quickly spread worldwide. Despite the absence of a vaccination or authorized drug specifically developed to combat this infection, certain medications recommended for other diseases have shown potential effectiveness in treating COVID-19, although without definitive confirmation. This review aims to evaluate the existing literature on the efficacy of these medications against COVID-19. The review encompasses various potential treatments, including antiviral medications, anti-malaria and anti-rheumatic drugs, vaccines, corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs), antipyretic and analgesic medicines, antiparasitic drugs, and statins. The analysis also addresses the potential benefits and drawbacks of these medications, as well as their effects on hypertension and diabetes. Although these therapies hold promise against COVID-19, further research, including suitable product production or clinical testing, is needed to establish their therapeutic efficacy.

Emerging Treatment Approaches for COVID-19 Infection: A Critical Review

In the present scenario, the SARS-CoV-2 virus has imposed enormous damage on human survival and the global financial system. It has been estimated that around 111 million people all around the world have been infected, and about 2.47 million people died due to this pandemic. The major symptoms were sneezing, coughing, cold, difficulty breathing, pneumonia, and multi-organ failure associated 1with SARS-CoV-2. Currently, two key problems, namely insufficient attempts to develop drugs against SARSCoV-2 and the lack of any biological regulating process, are mostly responsible for the havoc caused by this virus. Henceforth, developing a few novel drugs is urgently required to cure this pandemic. It has been noticed that the pathogenesis of COVID-19 is caused by two main events: infection and immune deficiency, that occur during the pathological process. Antiviral medication can treat both the virus and the host cells. Therefore, in the present review, the major approaches for the treatment have been divided into "target virus" and "target host" groups. These two mechanisms primarily rely on drug repositioning, novel approaches, and possible targets. Initially, we discussed the traditional drugs per the physicians' recommendations. Moreover, such therapeutics have no potential to fight against COVID-19. After that, detailed investigation and analysis were conducted to find some novel vaccines and monoclonal antibodies and conduct a few clinical trials to check their effectiveness against SARSCoV- 2 and mutant strains. Additionally, this study presents the most successful methods for its treatment, including combinatorial therapy. Nanotechnology was studied to build efficient nanocarriers to overcome the traditional constraints of antiviral and biological therapies.

The Effect of Coronavirus Disease 2019 on the Quality of Associated Care in Patients with Gastric Cancer

Coronavirus is a new virus that has affected human life on a large scale; it has infected millions of people and killed hundreds of thousands of people. In contrast, among cancers, stomach neoplasia is the most common cancer of the upper gastrointestinal (UGI) tract. COVID-19 disease has disrupted the optimal management of patients with cancer. Metastasis, deterioration of the patient's nutritional status, UGI bleeding, and increased surgical complications are all consequences of delayed treatment of patients with gastric cancer. However, there is still insufficient evidence on the immunogenicity of the vaccine and the protection provided by coronavirus vaccines in patients with cancer, especially those with immunodeficiency or those who are treated for certain types of cancers. Also, as part of the prevention and control of COVID-19 disease, nutritional support for patients with gastrointestinal cancer is particularly important, and the psychological and physiological limitations caused by the disease duration are hurting the well-being of patients. Therefore, the assessment of the impact of the coronavirus on cancer should be treated as an important issue, and healthcare professionals should be prepared to deal with the long-term effects of the coronavirus disease.

Antiviral activity of singlet oxygen-photogenerating perylene compounds against SARS-CoV-2: Interaction with the viral envelope and photodynamic virion inactivation

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has prompted great interest in novel broad-spectrum antivirals, including perylene-related compounds. In the present study, we performed a structure-activity relationship analysis of a series of perylene derivatives, which comprised a large planar perylene residue, and structurally divergent polar groups connected to the perylene core by a rigid ethynyl or thiophene linker. Most of the tested compounds did not exhibit significant cytotoxicity towards multiple cell types susceptible to SARS-CoV-2 infection, and did not change the expressions of cellular stress-related genes under normal light conditions. These compounds showed nanomolar or sub-micromolar dose-dependent anti-SARS-CoV-2 activity, and also suppressed the in vitro replication of feline coronavirus (FCoV), also termed feline infectious peritonitis virus (FIPV). Perylene compounds exhibited high affinity for liposomal and cellular membranes, and efficiently intercalated into the envelopes of SARS-CoV-2 virions, thereby blocking the viral-cell fusion machinery. Furthermore, the studied compounds were demonstrated to be potent photosensitizers, generating reactive oxygen species (ROS), and their anti-SARS-CoV-2 activities were considerably enhanced after irradiation with blue light. Our results indicated that photosensitization is the major mechanism underlying the anti-SARS-CoV-2 activity of perylene derivatives, with these compounds completely losing their antiviral potency under red light. Overall, perylene-based compounds are broad-spectrum antivirals against multiple enveloped viruses, with antiviral action based on light-induced photochemical damage (ROS-mediated, likely singlet oxygen-mediated), causing impairment of viral membrane rheology.

Lived experiences and meanings of the COVID-19 pandemic: A case of the elderly survivors

The extent of risk brought about by the COVID-19 pandemic on the well-being of the elderly has emphasized the need to investigate their experiences during these challenging times. This study was conducted to explore the elderly's lived experiences as COVID-19 patients and to understand how they make sense of and cope with what happened to them when infected with COVID-19. Using Husserl's descriptive phenomenology, 13 elderly from Naval, Biliran Province, Philippines were chosen as participants using purposive sampling. The total number of participants was determined through theoretical saturation. In-depth interviews and the writing of field notes were done to collect information on the participants' experiences. The transcripts were analyzed following Colaizzi's steps in descriptive phenomenological method of analysis. Four general themes emerged for the elderly's lived experiences during the pandemic. These included discrimination, social isolation, anxiety and stress, and fear. Findings revealed that despite the challenges the elderly encountered during the pandemic and when they tested positive for COVID-19, they had seen it as an opportunity to improve and change their practices. The strategies that the elderly employed to cope with the pandemic were all adaptive and have resulted in positive outcomes. Results of the study emphasize the need for more programs and policies to enhance the care and support provided to the elderly during a health crisis.

Infections associated with SARS-CoV-2 exploited via nanoformulated photodynamic therapy

Background and purpose

The pandemic of COVID-19 has highlighted the need for managing infectious diseases, which spreads by airborne transmission leading to serious health, social, and economic issues. SARS-CoV-2 is an enveloped virus with a 60-140 nm diameter and particle-like features, which majorly accounts for this disease. Expanding diagnostic capabilities, developing safe vaccinations with long-lasting immunity, and formulating effective medications are the strategies to be investigated.

Experimental approach

For the literature search, electronic databases such as Scopus, Google Scholar, MEDLINE, Embase, PubMed, and Web of Science were used as the source. Search terms like 'Nano-mediated PDT,' 'PDT for SARS-CoV-2', and 'Nanotechnology in treatment for SARS-CoV-2' were used. Out of 275 initially selected articles, 198 were chosen after the abstract screening. During the full-text screening, 80 papers were excluded, and 18 were eliminated during data extraction. Preference was given to articles published from 2018 onwards, but a few older references were cited for their valuable information.

Key results

Synthetic nanoparticles (NPs) have a close structural resemblance to viruses and interact greatly with their proteins due to their similarities in the configurations. NPs had previously been reported to be effective against a variety of viruses. In this way, with nanoparticles, photodynamic therapy (PDT) can be a viable alternative to antibiotics in fighting against microbial infections. The protocol of PDT includes the activation of photosensitizers using specific light to destroy microorganisms in the presence of oxygen, treating several respiratory diseases.

Conclusion

The use of PDT in treating COVID-19 requires intensive investigations, which has been reviewed in this manuscript, including a computational approach to formulating effective photosensitizers.

In Silico Substrate-Binding Profiling for SARS-CoV-2 Main Protease (Mpro) Using Hexapeptide Substrates

The SARS-CoV-2 main protease (M^pro) is essential for the life cycle of the COVID-19 virus. It cleaves the two polyproteins at 11 positions to generate mature proteins for virion formation. The cleavage site on these polyproteins is known to be Leu-Gln↓(Ser/Ala/Gly). A range of hexapeptides that follow the known sequence for recognition and cleavage was constructed using RDKit libraries and complexed with the crystal structure of M^pro (PDB ID 6XHM) through extensive molecular docking calculations. A subset of 131 of these complexes underwent 20 ns molecular dynamics simulations. The analyses of the trajectories from molecular dynamics included principal component analysis (PCA), and a method to compare PCA plots from separate trajectories was developed in terms of encoding PCA progression during the simulations. The hexapeptides formed stable complexes as expected, with reproducible molecular docking of the substrates given the extensiveness of the procedure. Only Lys-Leu-Gln*** (KLQ***) sequence complexes were studied for molecular dynamics. In this subset of complexes, the PCA analysis identified four classifications of protein motions across these sequences. KLQ*** complexes illustrated the effect of changes in substrate on the active site, with implications for understanding the substrate recognition of M^pro and informing the development of small molecule inhibitors.

Host Cell Membrane Capture by the SARS-CoV-2 Spike Protein Fusion Intermediate

Cell entry by SARS-CoV-2 is accomplished by the S2 subunit of the spike S protein on the virion surface by capture of the host cell membrane and fusion with the viral envelope. Capture and fusion require the prefusion S2 to transit to its potent fusogenic form, the fusion intermediate (FI). However, the FI structure is unknown, detailed computational models of the FI are unavailable, and the mechanisms and timing of membrane capture and fusion are not established. Here, we constructed a full-length model of the SARS-CoV-2 FI by extrapolating from known SARS-CoV-2 pre- and postfusion structures. In atomistic and coarse-grained molecular dynamics simulations the FI was remarkably flexible and executed giant bending and extensional fluctuations due to three hinges in the C-terminal base. The simulated configurations and their giant fluctuations are quantitatively consistent with SARS-CoV-2 FI configurations measured recently using cryo-electron tomography. Simulations suggested a host cell membrane capture time of ∼2 ms. Isolated fusion peptide simulations identified an N-terminal helix that directed and maintained binding to the membrane but grossly underestimated the binding time, showing that the fusion peptide environment is radically altered when attached to its host fusion protein. The large configurational fluctuations of the FI generated a substantial exploration volume that aided capture of the target membrane, and may set the waiting time for fluctuation-triggered refolding of the FI that draws the viral envelope and host cell membrane together for fusion. These results describe the FI as machinery that uses massive configurational fluctuations for efficient membrane capture and suggest novel potential drug targets.

Therapeutic Interventions for COVID-19

SARS-CoV-2, a novel coronavirus, is currently represented a major public health concern. The high transmission rate of this virus increases the mortality rate worldwide. To date, significant efforts and restricted regulations were performed around the world to control this crisis effectively, but unfortunately, there is no specific and successful therapy for COVID-19. Many approaches have been repurposed for SARS-CoV-2 treatment such as antivirals and anti-inflammatories. Furthermore, antibody therapies are one of the main and important approaches of SARS-CoV-2 infection treatment. In recent trials, various immunotherapeutic interventions such as convalescent plasma therapy and monoclonal antibodies, as well as immunomodulatory agents are being proposed. However, the development of a vaccine that provides durable protective immunity will be the most effective therapy for controlling possible epidemics of this virus. The current review summarized all the proposed therapeutic approaches together with information on their safety and efficacy in treating COVID-19, as well as the vaccine candidates. The provided comprehensive information regarding the applied therapeutic strategies against COVID-19 might help the scientific community in any progress toward the treatment of COVID-19 infection.

Pharmaceutical approaches for COVID-19: An update on current therapeutic opportunities

SARS-CoV-2, a newly discovered coronavirus, has been linked to the COVID-19 pandemic and is currently an important public health issue. Despite all the work done to date around the world, there is still no viable treatment for COVID-19. This study examined the most recent evidence on the efficacy and safety of several therapeutic options available including natural substances, synthetic drugs and vaccines in the treatment of COVID-19. Various natural compounds such as sarsapogenin, lycorine, biscoclaurine, vitamin B₁₂, glycyrrhizic acid, riboflavin, resveratrol and kaempferol, various vaccines and drugs such as AZD1222, mRNA-1273, BNT162b2, Sputnik V, and remdesivir, lopinavir, favipiravir, darunavir, oseltamivir, and umifenovir, resp., have been discussed comprehensively. We attempted to provide exhaustive information regarding the various prospective therapeutic approaches available in order to assist researchers and physicians in treating COVID-19 patients.

Development of 2-chloroquinoline based heterocyclic frameworks as dual inhibitors of SARS-CoV-2 MPro and PLPro

Evolution of new variants of SARS-CoV-2 warrant the need for the continued efforts in identifying target-oriented new drugs. Dual targeting agents against M^Pro and PL^Pro not only overcome the incomplete efficacy but also the drug resistance, which is common problem. Since both these are cysteine proteases, we designed 2-chloroquinoline based molecules with additional imine moiety in the middle as possible nucleophilic warheads. In the first round of design and synthesis, three molecules (C3, C4 and C5) inhibited (Ki < 2 μM) only M^Pro by binding covalently to C145 and one molecule (C10) inhibited both the proteases non-covalently (Ki < 2 μM) with negligible cytotoxicity. Further conversion of the imine in C10 to azetidinone (C11) improved the potency against both the enzymes in the nanomolar range (820 nM against M^Pro and 350 nM against PL^Pro) with no cytotoxicity. Conversion of imine to thiazolidinone (C12), reduced the inhibition by 3-5 folds against both the enzymes. Biochemical and computational studies suggest that C10-C12 bind in the substrate binding pocket of M^Pro and in the BL2 loop of the PL^Pro. Since these dual inhibitors have least cytotoxicity, they could be further explored as therapeutics against the SARS-CoV-2 and other analogous viruses.

The Association between COVID-19 Infection and Kidney Damage in a Regional University Hospital

Background and Objectives: Kidneys are one of the main targets for SARS-CoV-2. Early recognition and precautionary management are essential in COVID-19 patients due to the multiple origins of acute kidney injury and the complexity of chronic kidney disease management. The aims of this research were to investigate the association between COVID-19 infection and renal injury in a regional hospital. Materials and Methods: The data of 601 patients from the Vilnius regional university hospital between 1 January 2020 and 31 March 2021 were collected for this cross-sectional study. Demographic data (gender, age), clinical outcomes (discharge, transfer to another hospital, death), length of stay, diagnoses (chronic kidney disease, acute kidney injury), and laboratory test data (creatinine, urea, C-reactive protein, potassium concentrations) were collected and analyzed statistically. Results: Patients discharged from the hospital were younger (63.18 ± 16.02) than those from the emergency room (75.35 ± 12.41, p < 0.001), transferred to another hospital (72.89 ± 12.06, p = 0.002), or who died (70.87 ± 12.83, p < 0.001). Subsequently, patients who died had lower creatinine levels on the first day than those who survived (185.00 vs. 311.17 µmol/L, p < 0.001), and their hospital stay was longer (Spearman's correlation coefficient = -0.304, p < 0.001). Patients with chronic kidney disease had higher first-day creatinine concentration than patients with acute kidney injury (365.72 ± 311.93 vs. 137.58 ± 93.75, p < 0.001). Patients with acute kidney injury and chronic kidney disease complicated by acute kidney injury died 7.81 and 3.66 times (p < 0.001) more often than patients with chronic kidney disease alone. The mortality rate among patients with acute kidney injury was 7.79 (p < 0.001) times higher than among patients without these diseases. Conclusions: COVID-19 patients who developed acute kidney injury and whose chronic kidney disease was complicated by acute kidney injury had a longer hospital stay and were more likely to die.

Potential treatments of COVID-19: Drug repurposing and therapeutic interventions

The coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The infection is caused when Spike-protein (S-protein) present on the surface of SARS-CoV-2 interacts with human cell surface receptor, Angiotensin-converting enzyme 2 (ACE2). This binding facilitates SARS-CoV-2 genome entry into the human cells, which in turn causes infection. Since the beginning of the pandemic, many different therapies have been developed to combat COVID-19, including treatment and prevention. This review is focused on the currently adapted and certain other potential therapies for COVID-19 treatment, which include drug repurposing, vaccines and drug-free therapies. The efficacy of various treatment options is constantly being tested through clinical trials and in vivo studies before they are made medically available to the public.

The effect of multiple-dose ivermectin treatment on CD4+/CD8+ and the oxidative stress index in goats with udder viral papillomatosis

This study aims to reveal the therapeutic effect of ivermectin against Capra hircus papillomavirus (ChPV-1) infection and on the CD4⁺/CD8⁺ (cluster of differentiation) and oxidative stress index (OSI). Twenty hair goats naturally infected with ChPV-1 were divided into two groups with equal numbers as the ivermectin group and the control groups. Ivermectin was administered subcutaneously at a dose of 0.2 mg/kg to the goats in the ivermectin group on days 0, 7, and 21. Blood samples were collected from the vena jugularis on days 0, 21, 45, and 90. The cluster of differentiation4⁺/CD8⁺ ratio was significantly higher in the ivermectin group than in the control group on the 90th day. Furthermore, the CD8⁺ concentration was significantly decreased in the ivermectin group on the 90th day compared with the control group. Both total oxidant status (TOS) and OSI were found to be significantly higher in the control group on the 21st and 45th days than in the ivermectin group. On the 90th day, it was determined that the lesions in the ivermectin group improved significantly compared to those in the control group. Additionally, only in the ivermectin group was there a significant difference between the 90th day and the other days in terms of healing. As a result, it can be suggested that ivermectin has positive effects on the immune response and that its oxidative actions are of therapeutic value and do not harm the systemic oxidative status, as in untreated goats.

The roles of critical pro-inflammatory cytokines in the drive of cytokine storm during SARS-CoV-2 infection

In patients with severe COVID-19, acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome (MODS), and even mortality can result from cytokine storm, which is a hyperinflammatory medical condition caused by the excessive and uncontrolled release of pro-inflammatory cytokines. High levels of numerous crucial pro-inflammatory cytokines, such as interleukin-1 (IL-1), IL-2, IL-6, tumor necrosis factor-α, interferon (IFN)-γ, IFN-induced protein 10 kDa, granulocyte-macrophage colony-stimulating factor, monocyte chemoattractant protein-1, and IL-10 and so on, have been found in severe COVID-19. They participate in cascade amplification pathways of pro-inflammatory responses through complex inflammatory networks. Here, we review the involvements of these critical inflammatory cytokines in SARS-CoV-2 infection and discuss their potential roles in triggering or regulating cytokine storm, which can help to understand the pathogenesis of severe COVID-19. So far, there is rarely effective therapeutic strategy for patients with cytokine storm besides using glucocorticoids, which is proved to result in fatal side effects. Clarifying the roles of key involved cytokines in the complex inflammatory network of cytokine storm will help to develop an ideal therapeutic intervention, such as neutralizing antibody of certain cytokine or inhibitor of some inflammatory signal pathways.

A theoretical survey to find potential natural compound for inhibition of binding the RBD domain to ACE2 receptor based on plant antivirals

The spike protein of coronavirus is crucial in binding and arrival of the virus to the human cell via binding to the human ACE2 receptor. In this study, at first 25 antiviral phytochemicals were docked into the RBD domain of spike protein, and then all complexes and free RBD domains were separately subjected to molecular dynamics simulation for 100 ns and MM/PBSA binding free energy calculation. In this phase, four ligands were chosen as hit compounds and a natural compound database (NPASS) was screened based on high similarity with these ligands, and 367 ligands were found. Then the same previous procedure was repeated for these ligands and ADME properties were investigated. Finally, virtual screening and 4400 ns MD simulation and MM/PBSA calculation revealed that new ligands including NPC67959, NPC157855, NPC248793, and NPC216361 can inhibit the RBD domain of spike protein and we propose them as potential drugs for experimental studies.Communicated by Ramaswamy H. Sarma.

Evaluation of In Vitro and In Vivo Antiviral Activities of Vitamin D for SARS-CoV-2 and Variants

The COVID-19 pandemic has brought about unprecedented medical and healthcare challenges worldwide. With the continual emergence and spread of new COVID-19 variants, four drug compound libraries were interrogated for their antiviral activities against SARS-CoV-2. Here, we show that the drug screen has resulted in 121 promising anti-SARS-CoV-2 compounds, of which seven were further shortlisted for hit validation: citicoline, pravastatin sodium, tenofovir alafenamide, imatinib mesylate, calcitriol, dexlansoprazole, and prochlorperazine dimaleate. In particular, the active form of vitamin D, calcitriol, exhibits strong potency against SARS-CoV-2 on cell-based assays and is shown to work by modulating the vitamin D receptor pathway to increase antimicrobial peptide cathelicidin expression. However, the weight, survival rate, physiological conditions, histological scoring, and virus titre between SARS-CoV-2 infected K18-hACE2 mice pre-treated or post-treated with calcitriol were negligible, indicating that the differential effects of calcitriol may be due to differences in vitamin D metabolism in mice and warrants future investigation using other animal models.

Safety, Biodistribution, and Dosimetry Study of Meplazumab, a Potential COVID-19 Therapeutic Drug, with 131I-Labeling and SPECT Imaging

Coronavirus disease 2019 (COVID-19) is a serious threat to public health and is in urgent need of specific drugs. Meplazumab, a humanized monoclonal antibody targeting CD147, was confirmed to competitively block the binding between the spike of syndrome coronavirus 2 (SARS-CoV-2) and CD147, making meplazumab a promising candidate drug for COVID-19. In this study, biodistribution and dosimetry of 131I-labeled meplazumab were performed to further evaluate its potential as a therapeutic drug for COVID-19. 131I-meplazumab was both safe and tolerant in mice and healthy volunteers. A biodistribution study was performed in normal mice, and blood samples were used for pharmacokinetic analysis. Three healthy volunteers were included and subjected to single-photon-emission computed tomography (SPECT) imaging of 131I-meplazumab within 2 weeks. The distribution in mice and humans was consistent with the in vivo distribution of CD147. Biodistribution and SPECT imaging results exhibited that the liver was the organ with the highest uptake for both mice and humans. Deiodination of 131I-meplazumab can be observed in vivo, and taking Lugol's solution can protect the thyroid gland effectively. The pharmacokinetic characteristics of 131I-meplazumab in mice and humans best fit the two-compartment model. The clearance half-life (T1/2β) in mice and humans was 117.4 and 223.5 h, respectively. The results indicated that its pharmacokinetic properties in vivo were ideal. The effective dose calculated from healthy volunteers was 0.811 ± 0.260 mSv·MBq-1, which was twice the value calculated from mice. It was safe and feasible to perform human clinical imaging experiments using a diagnostic dose of 131I-meplazumab after thyroid closure by Lugol's solution. This study will provide more experimental basis for advancing the clinical translation of meplazumab and will be valuable in evaluating therapeutic interventions for patients with COVID-19, as well as providing a reference for clinical translation studies of other antibody drugs.

Pulmonary drug delivery: an effective and convenient delivery route to combat COVID-19

The recent outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China has spread rapidly around the world, leading to a widespread and urgent effort to develop and use comprehensive approaches in the treatment of COVID-19. While oral therapy is accepted as an effective and simple method, since the primary site of infection and disease progression of COVID-19 is mainly through the lungs, inhaled drug delivery directly to the lungs may be the most appropriate route of administration. To prevent or treat primary SARS-CoV-2 infections, it is essential to target the virus port of entry in the respiratory tract and airway epithelium, which requires rapid and high-intensity inhibition or control of viral entry or replication. To achieve success in this field, inhalation therapy is the most attractive treatment approach due to efficacy/safety profiles. In this review article, pulmonary drug delivery as a unique treatment option in lung diseases will be briefly reviewed. Then, possible inhalation therapies for the treatment of symptoms of COVID-19 will be discussed and the results of clinical trials will be presented. By pulmonary delivery of the currently approved drugs for COVID-19, efficacy of the treatment would be improved along with reducing systemic side effects.

Alpha to Omicron (Variants of Concern): Mutation Journey, Vaccines, and Therapy

Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) initially emerged in December 2019 and has subsequently expanded globally, leading to the ongoing pandemic. The extensive spread of various SARS-CoV-2 variants possesses a serious public health threat. An extensive literature search along with deep analysis was performed to describe and evaluate the characteristics of SARS-CoV-2 variants of concern in relation to the effectiveness of the current vaccines and therapeutics. The obtained results showed that several significant mutations have evolved during the COVID-19 pandemic. The developed variants and their various structural mutations can compromise the effectiveness of several vaccines, escape the neutralizing antibodies, and limit the efficiency of available therapeutics. Furthermore, deep analysis of the available data enables the prediction of the future impact of virus mutations on the ongoing pandemic along with the selection of appropriate vaccines and therapeutics.

Lessons Learnt from COVID-19: Computational Strategies for Facing Present and Future Pandemics

Since its outbreak in December 2019, the COVID-19 pandemic has caused the death of more than 6.5 million people around the world. The high transmissibility of its causative agent, the SARS-CoV-2 virus, coupled with its potentially lethal outcome, provoked a profound global economic and social crisis. The urgency of finding suitable pharmacological tools to tame the pandemic shed light on the ever-increasing importance of computer simulations in rationalizing and speeding up the design of new drugs, further stressing the need for developing quick and reliable methods to identify novel active molecules and characterize their mechanism of action. In the present work, we aim at providing the reader with a general overview of the COVID-19 pandemic, discussing the hallmarks in its management, from the initial attempts at drug repurposing to the commercialization of Paxlovid, the first orally available COVID-19 drug. Furthermore, we analyze and discuss the role of computer-aided drug discovery (CADD) techniques, especially those that fall in the structure-based drug design (SBDD) category, in facing present and future pandemics, by showcasing several successful examples of drug discovery campaigns where commonly used methods such as docking and molecular dynamics have been employed in the rational design of effective therapeutic entities against COVID-19.

Smart healthcare: A prospective future medical approach for COVID-19

COVID-19 has greatly affected human life for over 3 years. In this review, we focus on smart healthcare solutions that address major requirements for coping with the COVID-19 pandemic, including (1) the continuous monitoring of severe acute respiratory syndrome coronavirus 2, (2) patient stratification with distinct short-term outcomes (eg, mild or severe diseases) and long-term outcomes (eg, long COVID), and (3) adherence to medication and treatments for patients with COVID-19. Smart healthcare often utilizes medical artificial intelligence (AI) and cloud computing and integrates cutting-edge biological and optoelectronic techniques. These are valuable technologies for addressing the unmet needs in the management of COVID. By leveraging deep learning/machine learning capabilities and big data, medical AI can perform precise prognosis predictions and provide reliable suggestions for physicians' decision-making. Through the assistance of the Internet of Medical Things, which encompasses wearable devices, smartphone apps, internet-based drug delivery systems, and telemedicine technologies, the status of mild cases can be continuously monitored and medications provided at home without the need for hospital care. In cases that develop into severe cases, emergency feedback can be provided through the hospital for rapid treatment. Smart healthcare can possibly prevent the development of severe COVID-19 cases and therefore lower the burden on intensive care units.

Aspects of Nanotechnology for COVID-19 Vaccine Development and Its Delivery Applications

Coronavirus, a causative agent of the common cold to a much more complicated disease such as "severe acute respiratory syndrome (SARS-CoV-2), Middle East Respiratory Syndrome (MERS-CoV-2), and Coronavirus Disease 2019 (COVID-19)", is a member of the coronaviridae family and contains a positive-sense single-stranded RNA of 26-32 kilobase pairs. COVID-19 has shown very high mortality and morbidity and imparted a significantly impacted socioeconomic status. There are many variants of SARS-CoV-2 that have originated from the mutation of the genetic material of the original coronavirus. This has raised the demand for efficient treatment/therapy to manage newly emerged SARS-CoV-2 infections successfully. However, different types of vaccines have been developed and administered to patients but need more attention because COVID-19 is not under complete control. In this article, currently developed nanotechnology-based vaccines are explored, such as inactivated virus vaccines, mRNA-based vaccines, DNA-based vaccines, S-protein-based vaccines, virus-vectored vaccines, etc. One of the important aspects of vaccines is their administration inside the host body wherein nanotechnology can play a very crucial role. Currently, more than 26 nanotechnology-based COVID-19 vaccine candidates are in various phases of clinical trials. Nanotechnology is one of the growing fields in drug discovery and drug delivery that can also be used for the tackling of coronavirus. Nanotechnology can be used in various ways to design and develop tools and strategies for detection, diagnosis, and therapeutic and vaccine development to protect against COVID-19. The design of instruments for speedy, precise, and sensitive diagnosis, the fabrication of potent sanitizers, the delivery of extracellular antigenic components or mRNA-based vaccines into human tissues, and the administration of antiretroviral medicines into the organism are nanotechnology-based strategies for COVID-19 management. Herein, we discuss the application of nanotechnology in COVID-19 vaccine development and the challenges and opportunities in this approach.

Stokes-Mueller polarization-based analysis of model SARS-CoV-2 virions

Understanding the virology of the coronavirus at the structural level has gained utmost importance to overcome the constant and long-term health complications induced by them. In this work, the light scattering properties of SARS-CoV-2 of size 140 nm were simulated by using discrete dipole approximation (DDA) for two incident wavelengths 200 nm and 350 nm, respectively. Three different 3-dimensional (3D) models of SARS-CoV-2 corresponding to 15, 20, and 40 numbers of spike proteins on the viral capsid surface were constructed as target geometries for the DDA calculations. These models were assessed by employing Stokes-Mueller polarimetry to obtain individual polarization properties such as degree of polarization (DOP), degree of linear polarization (DOLP), and degree of circular polarization (DOCP). Irrespective of its spike numbers, all the coronavirus models were found to display higher DOP and DOCP values and negligibly small DOLP values for circularly polarized incident light, indicating the presence of chiral structures. On the other hand, the lack of understanding about the dependence of the Mueller matrix on its microstructural properties was overcome by transforming 16 Mueller elements into sub-matrices with specific structural and physical properties using Lu-Chipman-based Mueller matrix polar decomposition method. The obtained properties such as retardance, diattenuation, and depolarization were used for investigating the composition and microstructural information. The approach presented in this work has the potential to understand the virology of the coronavirus at the structural level and, therefore, will be beneficial in developing effective detection strategies by exploiting their characteristic electromagnetic scattering signatures.

SARS-CoV-2 Vaccines: Types, Working Principle, and Its Impact on Thrombosis and Gastrointestinal Disorders

In the current scenario of the coronavirus pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), considerable efforts have been made to control the pandemic by the development of a strong immune system through massive vaccination. Just after the discovery of the genetic sequences of SARS-CoV-2, the development of vaccines became the prime focus of scientists around the globe. About 200 SARS-CoV-2 candidate vaccines have already been entered into preclinical and clinical trials. Various traditional and novel approaches are being utilized as a broad range of platforms. Viral vector (replicating and non-replicating), nucleic acid (DNA and RNA), recombinant protein, virus-like particle, peptide, live attenuated virus, an inactivated virus approaches are the prominent attributes of the vaccine development. This review article includes the current knowledge about the platforms used for the development of different vaccines, their working principles, their efficacy, and the impacts of COVID-19 vaccines on thrombosis. We provide a detailed description of the vaccines that are already approved by administrative authorities. Moreover, various strategies utilized in the development of emerging vaccines that are in the trial phases along with their mode of delivery have been discussed along with their effect on thrombosis and gastrointestinal disorders.

Insights into the Structural Complexities of SARS-CoV-2 for Therapeutic and Vaccine Development

SARS-CoV-2 is a disease that endangers both human life and the economy. There was an 11- month period of relative evolutionary standstill following the appearance of SARS-CoV-2 in late 2019. However, the emergence of clusters of mutations known as' variants of concern 'with variable viral properties such as transmissibility and antigenicity defined the evolution of SARS-CoV-2. Several efforts have been made in recent months to understand the atomic level properties of SARS-CoV-2. A review of the literature on SARS-CoV-2 mutations is offered in this paper. The critical activities performed by different domains of the SARS-CoV-2 genome throughout the virus's entry into the host and overall viral life cycle are discussed in detail. These structural traits may potentially pave the way for the development of a vaccine and medication to combat the SARS-CoV-2 sickness.

Finding a prospective dual-target drug for the treatment of coronavirus disease by theoretical study

Spike protein of coronavirus is a key protein in binding and entrance of virus to the human cell via binding to the receptor-binding domain (RBD) domain of S1 subunit to peptidase domain region of ACE2 receptor. In this study, the possible effect of 24 antiviral drugs on the RBD domain of spike protein was investigated via docking and molecular dynamics simulation for finding a dual-target drug. At first, all drugs were docked to the RBD domain of spike protein, and then all complexes and free RBD domains were separately used for molecular dynamics simulation for 50 ns via amber18 software. The simulation results showed that 10 ligands from 28 ligands were separated from the RBD domain, and among 18 remained ligands, baloxavir marboxil, and danoprevir drugs, besides endonuclease activity and protease inhibitory, can bind to key residues of the RBD domain. Then these drugs have a dual target and should be more effective than current drugs, and experimental studies should be done on baloxavir marboxil and danoprevir as more potential drugs for coronavirus disease Communicated by Ramaswamy H. Sarma.

In Vitro Screening and MD Simulations of Thiourea Derivatives against SARS-CoV-2 in Association with Multidrug Resistance ABCB1 Transporter

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) is considered a global public health concern since it causes high morbidity and mortality. Recently, it has been reported that repurposed anti-COVID-19 drugs might interact with multidrug resistance ABC transporter, particularly ABCB1. In the current study, a series of thiourea derivatives were screened as potential inhibitors against SARS-CoV-2 by targeting the attachment of receptor binding domain (RBD) of spike protein with ACE2 and their interaction with human ABCB1 has also been explored. The results indicated strong impairment of RBD-ACE2 attachment by BB IV-46 with a percentage inhibition of 95.73 ± 1.79% relative to the positive control, while BB V-19 was proven inactive with a percentage inhibition of 50.90 ± 0.84%. The same compound (BB IV-46) interacted with ABCB1 and potentially inhibited cell proliferation of P-gp overexpressing cell line with an IC₅₀ value of 4.651 ± 0.06 μM. BB V-19, which was inactive against SARS-CoV-2, was inactive against ABCB1 with a higher IC₅₀ value of 35.72 ± 0.09 μM. Furthermore, molecular dynamics simulations followed by binding free-energy analysis explored the binding interaction of BB IV-46 and BB V-19 to RBD region of spike protein of SARS-CoV-2. The results confirmed that compound BB IV-46 interacted strongly with RBD with a significant binding energy (-127.0 kJ/mol), while BB V-19 interacted weakly (-29.30 kJ/mol). The key interacting residues of the RBD involved in binding included Leu441, Lys444, and Tyr449. This study highlights the importance of BB IV-46 against SARS-CoV-2; however, further pharmacokinetic and pharmacodynamics studies are needed to be done.

Different drug approaches to COVID-19 treatment worldwide: an update of new drugs and drugs repositioning to fight against the novel coronavirus

According to the World Health Organization (WHO), in the second half of 2022, there are about 606 million confirmed cases of COVID-19 and almost 6,500,000 deaths around the world. A pandemic was declared by the WHO in March 2020 when the new coronavirus spread around the world. The short time between the first cases in Wuhan and the declaration of a pandemic initiated the search for ways to stop the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or to attempt to cure the disease COVID-19. More than ever, research groups are developing vaccines, drugs, and immunobiological compounds, and they are even trying to repurpose drugs in an increasing number of clinical trials. There are great expectations regarding the vaccine's effectiveness for the prevention of COVID-19. However, producing sufficient doses of vaccines for the entire population and SARS-CoV-2 variants are challenges for pharmaceutical industries. On the contrary, efforts have been made to create different vaccines with different approaches so that they can be used by the entire population. Here, we summarize about 8162 clinical trials, showing a greater number of drug clinical trials in Europe and the United States and less clinical trials in low-income countries. Promising results about the use of new drugs and drug repositioning, monoclonal antibodies, convalescent plasma, and mesenchymal stem cells to control viral infection/replication or the hyper-inflammatory response to the new coronavirus bring hope to treat the disease.

Efectividad de enjuagues bucales contra virus de la familia coronavirus

La aparición del virus Sars-CoV-2 y la enfermedad Covid-19 han provocado un estado de emergencia en el sistema de salud. Teniendo en cuenta el potencial de la saliva como material contaminante, la práctica odontológica fue una de las áreas que se vio afectada debido al uso de instrumentos que pueden esparcir aerosoles y salpicaduras que contienen microorganismos hacia el medio ambiente. Por esta razón, conociendo su potencial en la inactivación de patógenos, se propuso la utilización de enjuagues bucales en la práctica clínica previo a la realización de procedimientos dentales, sin embargo la evidencia no es clara respecto a su efectividad. Objetivo. Establecer el estado de evidencia actual del efecto de los enjuagues bucales sobre los coronavirus que se encuentran en cavidad. Métodos. Se realizó una revisión sistemática siguiendo todos los parámetros descritos en las DirectricesPRISMA basada en información obtenida en los buscadores Science direct, Pubmed y Dentistry and Oral Science Source. Los criterios de selección incluyeron estudios in vivo e in vitro de texto completo que evidenciaron la efectividad del enjuague bucal contra coronavirus. Resultados. Se obtuvieron 90 artículos, de los cuales sólo 12 cumplían con los criterios de inclusión,8 in vitro y 4 in vivo, que fueron sometidos a la evaluación de calidad metodológica utilizando la lista de verificación de evaluación crítica del JBI.  Conclusiones. Los resultados sugieren que la povidona yodada es efectiva para la inactivación del virus Sars-coV-2 en todas sus concentraciones.

Comparative analysis of SARS-CoV-2 envelope viroporin mutations from COVID-19 deceased and surviving patients revealed implications on its ion-channel activities and correlation with patient mortality

One major obstacle in designing a successful therapeutic regimen to combat COVID-19 pandemic is the frequent occurrence of mutations in the SARS-CoV-2 resulting in patient to patient variations. Out of the four structural proteins of SARS-CoV-2 namely, spike, envelope, nucleocapsid and membrane, envelope protein governs the virus pathogenicity and induction of acute-respiratory-distress-syndrome which is the major cause of death in COVID-19 patients. These effects are facilitated by the viroporin (ion-channel) like activities of the envelope protein. Our current work reports metagenomic analysis of envelope protein at the amino acid sequence level through mining all the available SARS-CoV-2 genomes from the GISAID and coronapp servers. We found majority of mutations in envelope protein were localized at or near PDZ binding motif. Our analysis also demonstrates that the acquired mutations might have important implications on its structure and ion-channel activity. A statistical correlation between specific mutations (e.g. F4F, R69I, P71L, L73F) with patient mortalities were also observed, based on the patient data available for 18,691 SARS-CoV-2-genomes in the GISAID database till 30 April 2021. Albeit, whether these mutations exist as the cause or the effect of co-infections and/or co-morbid disorders within COVID-19 patients is still unclear. Moreover, most of the current vaccine and therapeutic interventions are revolving around spike protein. However, emphasizing on envelope protein's (1) conserved epitopes, (2) pathogenicity attenuating mutations, and (3) mutations present in the deceased patients, as reported in our present study, new directions to the ongoing efforts of therapeutic developments against COVID-19 can be achieved by targeting envelope viroporin.

Therapeutic Effects of Cannabinoids and Their Applications in COVID-19 Treatment

Cannabis sativa is one of the first medicinal plants used by humans. Its medical use remains controversial because it is a psychotropic drug whose use has been banned. Recently, however, some countries have approved its use, including for recreational and medical purposes, and have allowed the scientific study of its compounds. Cannabis is characterized by the production of special types of natural products called phytocannabinoids that are synthesized exclusively by this genus. Phytocannabinoids and endocannabinoids are chemically different, but both pharmacologically modulate CB1, CB2, GRP55, GRP119 and TRPV1 receptor activities, involving activities such as memory, sleep, mood, appetite and motor regulation, pain sensation, neuroinflammation, neurogenesis and apoptosis. Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are phytocannabinoids with greater pharmacological potential, including anti-inflammatory, neuroprotective and anticonvulsant activities. Cannabidiol is showing promising results for the treatment of COVID-19, due to its capability of acting on the unleashed cytokine storm, on the proteins necessary for both virus entry and replication and on the neurological consequences of patients who have been infected by the virus. Here, we summarize the latest knowledge regarding the advantages of using cannabinoids in the treatment of COVID-19.

Therapeutic and diagnostic applications of nanoparticles in the management of COVID-19: a comprehensive overview

In December 2019, Coronavirus Disease 2019 (COVID-19) was reported in Wuhan, China. Comprehensive strategies for quick identification, prevention, control, and remedy of COVID-19 have been implemented until today. Advances in various nanoparticle-based technologies, including organic and inorganic nanoparticles, have created new perspectives in this field. These materials were extensively used to control COVID-19 because of their specific attribution to preparing antiviral face masks, various safety sensors, etc. In this review, the most current nanoparticle-based technologies, applications, and achievements against the coronavirus were summarized and highlighted. This paper also offers nanoparticle preventive, diagnostic, and treatment options to combat this pandemic.

Antiviral peptides against SARS-CoV-2: therapeutic targets, mechanistic antiviral activity, and efficient delivery

The global pandemic of COVID-19 is a serious public health concern. Over 625 million confirmed cases and more than 6 million deaths have been recorded worldwide. Although several vaccines and antiviral medications have been developed, their efficacy is limited by the emerging new SARS-CoV-2 strains. Peptide-based therapeutics is a fast-growing class of new drugs and have unique advantages over large proteins and small molecules. Antiviral peptides (AVPs) are short polycationic antivirals with broad-spectrum effects, which have been shown to exert both prophylactic and therapeutic actions against reported coronaviruses. The potential therapeutic targets of AVPs are located either on the virus (e.g., E-protein and S-protein) to prohibit viral binding or host cells, particularly, those present on the cell surface (e.g., ACE2 and TMPRSS2). Despite AVPs having promising antiviral effects, their efficacy is limited by low bioavailability. Thus, nanoformulation is a prerequisite for prolonged bioavailability and efficient delivery. This review aimed to present an insight into the therapeutic AVP targets on both virus and host cells by discussing their antiviral activities and associated molecular mechanisms. Besides, it described the technique for discovering and developing possible AVPs based on their targets, as well as the significance of using nanotechnology for their efficient delivery against SARS-CoV-2.

Statistical analysis supports UTR (untranslated region) deletion theory in SARS-CoV-2

It was noticed that the mortality rate of SARS-CoV-2 infection experienced a significant declination in the early stage of the epidemic. We suspect that the sharp deterioration of virus toxicity is related to the deletion of the untranslated region (UTR) of the virus genome. It was found that the genome length of SARS-CoV-2 engaged a significant truncation due to UTR deletion after a mega-sequence analysis. Sequence similarity analysis further indicated that short UTR strains originated from its long UTR ancestors after an irreversible deletion. A good correlation was discovered between genome length and mortality, which demonstrated that the deletion of the virus UTR significantly affected the toxicity of the virus. This correlation was further confirmed in a significance analysis of the genetic influence on the clinical outcomes. The viral genome length of hospitalized patients was significantly more extensive than that of asymptomatic patients. In contrast, the viral genome length of asymptomatic was considerably longer than that of ordinary patients with symptoms. A genome-level mutation scanning was performed to systematically evaluate the influence of mutations at each position on virulence. The results indicated that UTR deletion was the primary driving force in alternating virus virulence in the early evolution. In the end, we proposed a mathematical model to explain why this UTR deletion was not continuous.