Feline Coronavirus Infections

• First Described: 1963 (Holzworth, 1963);a viral etiology was not identified until the 1970s. • Cause: Feline coronavirus (family Coronaviridae, genus Coronavirus). • Affected Hosts: Cats and wild felids, especially cheetahs. • Modes of Transmission: Fecal-oral (FECV), internal mutation (FIPV) • Geographic Distribution: Worldwide. • Major Clinical Signs: Fever, lethargy, inappetence, vomiting, diarrhea, dehydration, icterus, tachypnea, uveitis, neurologic signs, abdominal distention due to ascites. • Differential Diagnoses: Toxoplasmosis, congestive heart failure, carcinomatosis, lymphoma, pancreatitis, rabies, cryptococcosis, bacterial peritonitis, pyothorax, bacterial meningitis, chronic stomatitis, multiple myeloma, FeLV or FIV infection. • Human Health Significance: Feline coronaviruses do not infect humans. © 2021 Elsevier Inc. All rights reserved.

Monkeypox (mpox) is a new problem on a global scale for humanity.

Purpose - to draw attention to an infection that was little known, but has now become a global problem for society;to familiarize readers with the peculiarities of the 2022 monkeypox outbreak and to increase the level of alertness of doctors to this disease. Monkeypox is a global problem because the disease is spreading rapidly, covering 111 countries. Three cases were diagnosed in Ukraine. It is predominantly a self-limited infection, but there are severe and deadly complications. The lethality of this disease ranges from 0% to 11%. The course of the disease is more severe in children and people with reduced immunity. Vertical transmission of the virus from mother to child is possible, resulting in congenital monkeypox. Monkeypox is a zoonotic disease and its natural reservoir is not exactly known, but rodents are most likely to act. In most cases, person-to-person transmission of the virus occurs through close skin to skin contact, often during sexual intercourse. At the beginning of the outbreak 98% of cases of disease were was diagnosed in homo- and bisexuals. Airborne transmission is also possible. Infection is possible through close contact with infectious skin lesions. Clinically, the initial period resembles influenza, but lymphadenopathy is characteristic, which is considered a pathognomonic symptom of mpox. The rash is similar to that of chickenpox, but with more prevalent location on palms and soles than in chickenpox. In the presence of a vesicular rash in a patient, it is necessary to exclude monkeypox. PCR diagnostics of the virus in samples of vesicles or crusts has the greatest diagnostic value. Hygienic skin care is important. Antiviral drugs (tecovirimat, brincidofovir) are recommended only in severe cases. To reduce the spread of infection, international rules apply as for other infections, such as COVID-19. The monkeypox virus vaccine is recommended primarily for groups at risk of infection, including medical personnel who may come into contact with the patient or samples for laboratory testing. Being aware for this infection, following international health regulations, it is possible to prevent the further spread of monkeypox.Copyright © 2023 Tomsk State University. All rights reserved.

Structure-based virtual identification of natural inhibitors of SARS-CoV-2 and its Delta and Omicron variant proteins

Plain language summaryMutant strains of SARS-CoV-2 called 'variants of concern' (VOCs) are linked to a good ability to infect, re-infect and spread among people. They are also linked to poor ability to fight the disease and reduced effectiveness of vaccines. Delta and Omicron are important VOCs because they are difficult to control and treat. Specific resistance to some drugs used to treat COVID-19 poses a further challenge. Therefore, discovering natural or plant-derived drugs with no known resistance would be valuable to the treatment of COVID-19. In this study, we screen and identify seven plant-derived compounds that may be useful to treating COVID-19 - we identify Quercetin-3-acetyl-glucoside, Rutin, Kaempferol, Catechin, Orientin, Obetrioside and Neridienone A as potential candidates. Orientin, Obetrioside, Catechin and Neridienone A are identified as candidates against Delta and Omicron for the first time. Aim: Structure-based identification of natural compounds against SARS-CoV-2, Delta and Omicron target proteins. Materials & methods: Several known antiviral natural compounds were subjected to molecular docking and MD simulation against SARS-CoV-2 Mpro, Helicase and Spike, including Delta and Omicron Spikes. Results: Of the docked ligands, 20 selected for each complex exhibited overall good binding affinities (-7.79 to -5.06 kcal/mol) with acceptable physiochemistry following Lipinski's rule. Finally, two best ligands from each complex upon simulation showed structural stability and compactness. Conclusion: Quercetin-3-acetyl-glucoside, Rutin, Kaempferol, Catechin, Orientin, Obetrioside and Neridienone A were identified as potential inhibitors of SARS-CoV-2 Mpro, Helicase and Spike, while Orientin and Obetrioside also showed good binding-affinities with Omicron Spike. Catechin and Neridienone A formed stable complexes with Delta Spike. Tweetable We report structure-based identification of natural compounds viz., Quercetin-3-acetyl-glucoside, Rutin, Kaempferol, Catechin, Orientin, Obetrioside and Neridienone A against SARS-CoV-2 Mpro, Helicase and Spike as well as Delta and Omicron Spike proteins.

Parallel use of human stem cell lung and heart models provide insights for SARS-CoV-2 treatment.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) primarily infects the respiratory tract, but pulmonary and cardiac complications occur in severe coronavirus disease 2019 (COVID-19). To elucidate molecular mechanisms in the lung and heart, we conducted paired experiments in human stem cell-derived lung alveolar type II (AT2) epithelial cell and cardiac cultures infected with SARS-CoV-2. With CRISPR-Cas9-mediated knockout of ACE2, we demonstrated that angiotensin-converting enzyme 2 (ACE2) was essential for SARS-CoV-2 infection of both cell types but that further processing in lung cells required TMPRSS2, while cardiac cells required the endosomal pathway. Host responses were significantly different; transcriptome profiling and phosphoproteomics responses depended strongly on the cell type. We identified several antiviral compounds with distinct antiviral and toxicity profiles in lung AT2 and cardiac cells, highlighting the importance of using several relevant cell types for evaluation of antiviral drugs. Our data provide new insights into rational drug combinations for effective treatment of a virus that affects multiple organ systems.

Mechanistic-Based Classification of Endocytosis-Related Inhibitors: Does It Aid in Assigning Drugs against SARS-CoV-2?

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) canonically utilizes clathrin-mediated endocytosis (CME) and several other endocytic mechanisms to invade airway epithelial cells. Endocytic inhibitors, particularly those targeting CME-related proteins, have been identified as promising antiviral drugs. Currently, these inhibitors are ambiguously classified as chemical, pharmaceutical, or natural inhibitors. However, their varying mechanisms may suggest a more realistic classification system. Herein, we present a new mechanistic-based classification of endocytosis inhibitors, in which they are segregated among four distinct classes including: (i) inhibitors that disrupt endocytosis-related protein-protein interactions, and assembly or dissociation of complexes; (ii) inhibitors of large dynamin GTPase and/or kinase/phosphatase activities associated with endocytosis; (iii) inhibitors that modulate the structure of subcellular components, especially the plasma membrane, and actin; and (iv) inhibitors that cause physiological or metabolic alterations in the endocytosis niche. Excluding antiviral drugs designed to halt SARS-CoV-2 replication, other drugs, either FDA-approved or suggested through basic research, could be systematically assigned to one of these classes. We observed that many anti-SARS-CoV-2 drugs could be included either in class III or IV as they interfere with the structural or physiological integrity of subcellular components, respectively. This perspective may contribute to our understanding of the relative efficacy of endocytosis-related inhibitors and support the optimization of their individual or combined antiviral potential against SARS-CoV-2. However, their selectivity, combined effects, and possible interactions with non-endocytic cellular targets need more clarification.

Synthesis and Antiviral Efficacy of Pyrimidine Analogs Targeting Viral Pathways

To date, viruses are known to cause chronic to acute pathogenesis. Nevertheless, antiviral drugs have been known for their medicinal applications for the last few decades to treat infections caused by these pathogens. Despite advancements in the field of vaccination and antiviral drugs, there is a need for a molecule that can eradicate or control viral infection without getting resistance from pathogens will be a real challenge. This review covers possible ways to treat viral infections with pyrimidine and its mimics compared to known antiviral drugs. A comprehensive study of the report accomplished synthetic routes of pyrimidine analogs and their target-specific antiviral potential. The present review article covers literature from 2018 to 2022.

Advancements in organs-on-chips technology for viral disease and anti-viral research

Disease models that can accurately recapitulate human pathophysiology during infection and clinical response to antiviral therapeutics are still lacking, which represents a major barrier in drug development. The emergence of human Organs-on-a-Chip that integrated microfluidics with three-dimensional (3D) cell culture, may become the potential solution for this urgent need. Human Organs-on-a-Chip aims to recapitulate human pathophysiology by incorporating tissue-relevant cell types and their microenvironment, such as dynamic fluid flow, mechanical cues, tissue–tissue interfaces, and immune cells to increase the predictive validity of in vitro experimental models. Human Organs-on-a-Chip has a broad range of potential applications in basic biomedical research, preclinical drug development, and personalized medicine. This review focuses on its use in the fields of virology and infectious diseases. We reviewed various types of human Organs-on-a-Chip-based viral infection models and their application in studying viral life cycle, pathogenesis, virus-host interaction, and drug responses to virus- and host-targeted therapies. We conclude by proposing challenges and future research avenues for leveraging this promising technology to prepare for future pandemics.

Potential herb‒drug interactions between anti-COVID-19 drugs and traditional Chinese medicine.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide. Effective treatments against COVID-19 remain urgently in need although vaccination significantly reduces the incidence, hospitalization, and mortality. At present, antiviral drugs including Nirmatrelvir/Ritonavir (PaxlovidTM), Remdesivir, and Molnupiravir have been authorized to treat COVID-19 and become more globally available. On the other hand, traditional Chinese medicine (TCM) has been used for the treatment of epidemic diseases for a long history. Currently, various TCM formulae against COVID-19 such as Qingfei Paidu decoction, Xuanfei Baidu granule, Huashi Baidu granule, Jinhua Qinggan granule, Lianhua Qingwen capsule, and Xuebijing injection have been widely used in clinical practice in China, which may cause potential herb-drug interactions (HDIs) in patients under treatment with antiviral drugs and affect the efficacy and safety of medicines. However, information on potential HDIs between the above anti-COVID-19 drugs and TCM formulae is lacking, and thus this work seeks to summarize and highlight potential HDIs between antiviral drugs and TCM formulae against COVID-19, and especially pharmacokinetic HDIs mediated by metabolizing enzymes and/or transporters. These well-characterized HDIs could provide useful information on clinical concomitant medicine use to maximize clinical outcomes and minimize adverse and toxic effects.

Changing Trends in the Global Consumption of Treatments Used in Hospitalized Patients for COVID-19: A Time Series Multicentre Study.

AIM: To analyze trends in the prescription of COVID-19 treatments for hospitalized patients during the pandemic. METHODS: Multicenter, ecological, time-series study of aggregate data for all adult patients with COVID-19 treated in five acute-care hospitals in Barcelona, Spain, between March 2020 and May 2021. Trends in the monthly prevalence of drugs used against COVID-19 were analyzed by the Mantel-Haenszel test. RESULTS: The participating hospitals admitted 22,277 patients with COVID-19 during the study period, reporting an overall mortality of 10.8%. In the first months of the pandemic, lopinavir/ritonavir and hydroxychloroquine were the most frequently used antivirals, but these fell into disuse and were replaced by remdesivir in July 2020. By contrast, the trend in tocilizumab use varied, first peaking in April and May 2020, declining until January 2021, and showing a discrete upward trend thereafter. Regarding corticosteroid use, we observed a notable upward trend in the use of dexamethasone 6 mg per day from July 2020. Finally, there was a high prevalence of antibiotics use, especially azithromycin, in the first three months, but this decreased thereafter. CONCLUSIONS: Treatment for patients hospitalized with COVID-19 evolved with the changing scientific evidence during the pandemic. Initially, multiple drugs were empirically used that subsequently could not demonstrate clinical benefit. In future pandemics, stakeholders should strive to promote the early implementation of adaptive randomized clinical trials.

Research progress on drugs for the treatment of COVID-19

At present, coronavirus disease-19 (COVID-19) caused by novel coronavirus (SARS-CoV-2) has been spreading around the world, but no specific therapeutic drug or vaccine has been developed for the virus. By collecting the latest literature and searching related database websites, the biological characteristics and main targets of SARS-CoV-2, the clinical therapeu tic drugs and the latest drug research were reviewed to provide information for clinical treatment and provide reference for the research and development of new drugs against SARS-CoV-2.Copyright © 2020 Publication Centre of Anhui Medical University. All rights reserved.

Omicron variant evolution on vaccines and monoclonal antibodies.

The severe acute respiratory syndrome coronavirus (SARS-CoV)-2 responsible for the global COVID-19 pandemic has caused almost 760 million confirmed cases and 7 million deaths worldwide, as of end-February 2023. Since the beginning of the first COVID-19 case, several virus variants have emerged: Alpha (B1.1.7), Beta (B135.1), Gamma (P.1), Delta (B.1.617.2) and then Omicron (B.1.1.529) and its sublineages. All variants have diversified in transmissibility, virulence, and pathogenicity. All the newly emerging SARS-CoV-2 variants appear to contain some similar mutations associated with greater "evasiveness" of the virus to immune defences. From early 2022 onward, several Omicron subvariants named BA.1, BA.2, BA.3, BA.4, and BA.5, with comparable mutation forms, have followed. After the wave of contagions caused by Omicron BA.5, a new Indian variant named Centaurus BA.2.75 and its new subvariant BA.2.75.2, a second-generation evolution of the Omicron variant BA.2, have recently been identified. From early evidence, it appears that this new variant has higher affinity for the cell entry receptor ACE-2, making it potentially able to spread very fast. According to the latest studies, the BA.2.75.2 variant may be able to evade more antibodies in the bloodstream generated by vaccination or previous infection, and it may be more resistant to antiviral and monoclonal antibody drug treatments. In this manuscript, the authors highlight and describe the latest evidences and critical issues have emerged on the new SARS-CoV-2 variants.

Discovery of quinazolin-4-one-based non-covalent inhibitors targeting the severe acute respiratory syndrome coronavirus 2 main protease (SARS-CoV-2 Mpro).

The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a great threat to public health while various vaccines are available worldwide. Main protease (Mpro) has been validated as an effective anti-COVID-19 drug target. Using medicinal chemistry and rational drug design strategies, we identified a quinazolin-4-one series of nonpeptidic, noncovalent SARS-CoV-2 Mpro inhibitors based on baicalein, 5,6,7-trihydroxy-2-phenyl-4H-chromen-4-one. In particular, compound C7 exhibits superior inhibitory activity against SARS-CoV-2 Mpro relative to baicalein (IC50 = 0.085 ± 0.006 and 0.966 ± 0.065 µM, respectively), as well as improved physicochemical and drug metabolism and pharmacokinetics (DMPK) properties. In addition, C7 inhibits viral replication in SARS-CoV-2-infected Vero E6 cells more effectively than baicalein (EC50 = 1.10 ± 0.12 and 5.15 ± 1.64 µM, respectively) with low cytotoxicity (CC50 ＞ 50 µM). An X-ray co-crystal structure reveals a non-covalent mechanism of action, and a noncanonical binding mode not observed by baicalein. These results suggest that C7 represents a promising lead for development of more effective SARS-CoV-2 Mpro inhibitors and anti-COVID-19 drugs.

Antiviral drugs in wastewater are on the rise as emerging contaminants: A comprehensive review of spatiotemporal characteristics, removal technologies and environmental risks.

Antiviral drugs (ATVs) are widely used to treat illnesses caused by viruses. Particularly, ATVs were consumed in such large quantities during the pandemic that high concentrations were detected in wastewater and aquatic environment. Since ATVs are not fully absorbed by the human or animal body, this results in large amounts of them being discharged into the sewage through urine or feces. Most ATVs can be degraded by microbes at wastewater treatment plants (WWTPs), while some ATVs either require deep treatment to reduce concentration and toxicity. Parent and metabolites residing in effluent posed a varying degree of risk when entering the aquatic environment, while increasing the potential of natural reservoirs for environmentally acquired antiviral drug resistance potential. There is a rising research on the behavior of ATVs in the environment has surged since the pandemic. In the context of multiple viral diseases worldwide, especially during the current COVID-19 pandemic, a comprehensive assessment of the occurrence, removal, and risk of ATVs is urgently needed. This review aims to discuss the fate of ATVs in WWTPs from various regions in the world with wastewater as the main analyzing object. The ultimate goal is to focus on ATVs with high ecological impact and regulate their use or develop advanced treatment technologies to mitigate the risk to the environment.

Investigation of antiviral substances in Covid 19 by Molecular Docking: In Silico Study

Aims: This paper aimed to investigate the antiviral drugs against Sars-Cov-2 main protease (MPro) using in silico methods. Material(s) and Method(s): A search was made for antiviral drugs in the PubChem database and antiviral drugs such as Bictegravir, Emtricitabine, Entecavir, Lamivudine, Tenofovir, Favipiravir, Hydroxychloroquine, Lopinavir, Oseltamavir, Remdevisir, Ribavirin, Ritonavir were included in our study. The protein structure of Sars-Cov-2 Mpro (PDB ID: 6LU7) was taken from the Protein Data Bank (www.rcsb. Org) system and included in our study. Molecular docking was performed using AutoDock/Vina, a computational docking program. Protein-ligand interactions were performed with the AutoDock Vina program. 3D visualizations were made with the Discovery Studio 2020 program. N3 inhibitor method was used for our validation. Result(s): In the present study, bictegravir, remdevisir and lopinavir compounds in the Sars-Cov-2 Mpro structure showed higher binding affinity compared to the antiviral compounds N3 inhibitor, according to our molecular insertion results. However, the favipiravir, emtricitabine and lamuvidune compounds were detected very low binding affinity. Other antiviral compounds were found close binding affinity with the N3 inhibitor. Conclusion(s): Bictegravir, remdevisir and lopinavir drugs showed very good results compared to the N3 inhibitor. Therefore, they could be inhibitory in the Sars Cov-2 Mpro target.Copyright © 2023 Oner E et al.

A practical guide to statistics for general practice

EVIDENCE-BASED MEDICINE is a well-established part of general practice in Australia.1 Understanding research is embedded within the current curriculum of The Royal Australian College of General Practitioners (RACGP), with the ability to discuss 'scientific and statistical information' for clinical decisions listed as a required skillset for general practitioners (GPs).2 In the past few years, the COVID-19 pandemic has further highlighted that interpreting epidemiology and statistics is not only relevant for GP academics, but is also an integral part of clinical care.3 For example, GPs are often the first point of contact for patients asking about the evidence for masks, diagnostic accuracy of COVID-19 tests, vaccine efficacy and effectiveness of new antiviral treatments. In clinical practice, framing a research question, conducting a database search and critical appraisal of the selected paper are key first steps in interpreting and using research evidence.

Stability and WBE biomarkers possibility of 17 antiviral drugs in sewage and gravity sewers.

Wastewater-based epidemiology (WBE) is a promising technique for monitoring the rapidly increasing use of antiviral drugs during the COVID-19 pandemic. It is essential to evaluate the in-sewer stability of antiviral drugs in order to determine appropriate biomarkers. This study developed an analytical method for quantification of 17 typical antiviral drugs, and investigated the stability of target compounds in sewer through 4 laboratory-scale gravity sewer reactors. Nine antiviral drugs (lamivudine, acyclovir, amantadine, favipiravir, nevirapine, oseltamivir, ganciclovir, emtricitabine and telbivudine) were observed to be stable and recommended as appropriate biomarkers for WBE. As for the other 8 unstable drugs (abacavir, arbidol, ribavirin, zidovudine, ritonavir, lopinavir, remdesivir and efavirenz), their attenuation was driven by adsorption, biodegradation and diffusion. Moreover, reaction kinetics revealed that the effects of sediments and biofilms were regarded to be independent in gravity sewers, and the rate constants of removal by biofilms was directly proportional to the ratio of surface area against wastewater volume. The study highlighted the potential importance of flow velocity for compound stability, since an increased flow velocity significantly accelerated the removal of unstable biomarkers. In addition, a framework for graded evaluation of biomarker stability was proposed to provide reference for researchers to select suitable WBE biomarkers. Compared with current classification method, this framework considered the influences of residence time and different removal mechanisms, which additionally screened four antiviral drugs as viable WBE biomarkers. This is the first study to report the stability of antiviral drugs in gravity sewers.

Drug Design Strategies for the Treatment of Coronavirus Infection

The increasing size and density of the human population is leading to an increasing risk of infectious diseases that threaten to spread yet another pandemics. The widespread use of vaccination has reduced morbidity and mortality associated with viral infections and in some cases eradicated the virus from the population entirely. Regrettably, some virus species retain the ability to mutate rapidly and thus evade the vaccine-induced immune response. New antiviral drugs are therefore needed for the treatment and prevention of viral diseases. Modern research into the structures and properties of viral proteases, which are of key importance in the life cycle of viruses, makes it possible, in our opinion, to turn these enzymes into promising targets for the development of effective viral disease control methods.

COVID-19: Impact, Diagnosis, Management and Phytoremediation

COVID-19, or SARS-CoV-2, is an extremely deadly virus that is responsible for over half a million deaths of people in the world. This virus originated in China in December 2019 and rapidly spread worldwide in 2-3 months, and affected every part of the world. Its life-threatening nature forced governments in all countries to take emergency steps of lockdown that affected the entire world's education, health, social and economic aspects. Due to the implementation of these emergencies, the population is facing psychological, social and financial problems. Additionally, this pandemic has significantly influenced the health care systems as all the resources from governments of all countries were directed to invest funds to discover new diagnostic tests and manage COVID-19 infection. The impact of the COVID-19 pandemic on the education and social life of the population is described in this article. Additionally, the diagnosis, management, and phytoremedia-tion to control the spread of COVID-19 and traditional medicinal plants' role in managing its mild symptoms have been discussed.Copyright © 2023 Bentham Science Publishers.

Post-translational modifications: Host defence mechanism, pathogenic weapon, and emerged target of anti-infective drugs

Post-translational modifications are changes introduced to proteins after their translation. They are the means to generate molecular diversity, expand protein function, control catalytic activity and trigger quick responses to a wide range of stimuli. Moreover, they regulate numerous biological processes, including pathogen invasion and host defence mechanisms. It is well established that bacteria and viruses utilize post-translational modifications on their own or their host's proteins to advance their pathogenicity. Doing so, they evade immune responses, target signaling pathways and manipulate host cytoskeleton to achieve survival, replication and propagation. Many bacterial species secrete virulence factors into the host and mediate hostpathogen interactions by inducing post-translational modifications that subvert fundamental cellular processes. Viral pathogens also utilize post translational modifications in order to overcome the host defence mechanisms and hijack its cellular machinery for their replication and propagation. For example, many coronavirus proteins are modified to achieve host invasion, evasion of immune responses and utilization of the host translational machinery. PTMs are also considered potential targets for the development of novel therapeutics from natural products with antibiotic properties, like lasso peptides and lantibiotics. The last decade, significant progress was made in understanding the mechanisms that govern PTMs and mediate regulation of protein structure and function. This urges the identification of relevant molecular targets, the design of specific drugs and the discovery of PTM-based medicine. Therefore, PTMs emerge as a highly promising field for the investigation and discovery of new therapeutics for many infectious diseases.Copyright © 2021 Bentham Science Publishers.