Chloroquine and hydroxychloroquine in the treatment of COVID-19: the never-ending story

Coordination chemistry suggests that independently observed benefits of metformin and Zn2+ against COVID-19 are not independent

Independent trials indicate that either oral Zn2+ or metformin can separately improve COVID-19 outcomes by approximately 40%. Coordination chemistry predicts a mechanistic relationship and therapeutic synergy. Zn2+ deficit is a known risk factor for both COVID-19 and non-infectious inflammation. Most dietary Zn2+ is not absorbed. Metformin is a naked ligand that presumably increases intestinal Zn2+ bioavailability and active absorption by cation transporters known to transport metformin. Intracellular Zn2+ provides a natural buffer of many protease reactions; the variable "set point" is determined by Zn2+ regulation or availability. A Zn2+-interactive protease network is suggested here. The two viral cysteine proteases are therapeutic targets against COVID-19. Viral and many host proteases are submaximally inhibited by exchangeable cell Zn2+. Inhibition of cysteine proteases can improve COVID-19 outcomes and non-infectious inflammation. Metformin reportedly enhances the natural moderating effect of Zn2+ on bioassayed proteome degradation. Firstly, the dissociable metformin-Zn2+ complex could be actively transported by intestinal cation transporters; thereby creating artificial pathways of absorption and increased body Zn2+ content. Secondly, metformin Zn2+ coordination can create a non-natural protease inhibitor independent of cell Zn2+ content. Moderation of peptidolytic reactions by either or both mechanisms could slow (a) viral multiplication (b) viral invasion and (c) the pathogenic host inflammatory response. These combined actions could allow development of acquired immunity to clear the infection before life-threatening inflammation. Nirmatrelvir (Paxlovid®) opposes COVID-19 by selective inhibition the viral main protease by a Zn2+-independent mechanism. Pending safety evaluation, predictable synergistic benefits of metformin and Zn2+, and perhaps metformin/Zn2+/Paxlovid® co-administration should be investigated.

Inhibition of endocytic uptake of severe acute respiratory syndrome coronavirus 2 and endo-lysosomal acidification by diphenoxylate

Cell culture-based screening of a chemical library identified diphenoxylate as an antiviral agent against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The observed 50% effective concentrations ranged between 1.4 and 4.9 µM against the original wild-type strain and its variants. Time-of-addition experiments indicated that diphenoxylate is an entry blocker targeting a host factor involved in viral infection. Fluorescence microscopic analysis visualized that diphenoxylate prevented SARS-CoV-2 particles from penetrating the cell membrane and also impaired endo-lysosomal acidification. Diphenoxylate exhibited a synergistic inhibitory effect on SARS-CoV-2 infection in human lung epithelial Calu-3 cells when combined with a transmembrane serine protease 2 (TMPRSS2) inhibitor, nafamostat. This synergy suggested that efficient antiviral activity is achieved by blocking both TMPRSS2-mediated early and endosome-mediated late SARS-CoV-2 entry pathways. The antiviral efficacy of diphenoxylate against SARS-CoV-2 was reproducible in a human tonsil organoids system. In a transgenic mouse model expressing the obligate SARS-CoV-2 receptor, human angiotensin-converting enzyme 2, intranasal administration of diphenoxylate (10 mg/kg/day) significantly reduced the viral RNA copy number in the lungs by 70% on day 3. This study underscores that diphenoxylate represents a promising core scaffold, warranting further exploration for chemical modifications aimed at developing a new class of clinically effective antiviral drugs against SARS-CoV-2.

Zinc complexes of chloroquine and hydroxychloroquine versus the mixtures of their components: Structures, solution equilibria/speciation and cellular zinc uptake

The zinc complexes of chloroquine (CQ; [Zn(CQH+)Cl3]) and hydroxychloroquine (HO-CQ; [Zn(HO-CQH+)Cl3]) were synthesized and characterized by X-Ray structure analysis, FT-IR, NMR, UV-Vis spectroscopy, and cryo-spray mass spectrometry in solid state as well as in aqueous and organic solvent solutions, respectively. In acetonitrile, up to two Zn2+ ions bind to CQ and HO-CQ through the tertiary amine and aromatic nitrogen atoms (KN-aminCQ = (3.8 ± 0.5) x 104 M-1 and KN-aromCQ = (9.0 ± 0.7) x 103 M-1 for CQ, and KN-aminHO-CQ = (3.3 ± 0.4) x 104 M-1 and KN-aromHO-CQ = (1.6 ± 0.2) x 103 M-1 for HO-CQ). In MOPS buffer (pH 7.4) the coordination proceeds through the partially deprotonated aromatic nitrogen, with the corresponding equilibrium constants of KN-arom(aq)CQ = (3.9 ± 1.9) x 103 M-1and KN-arom(aq)HO-CQ = (0.7 + 0.4) x 103 M-1 for CQ and HO-CQ, respectively. An apparent partition coefficient of 0.22 was found for [Zn(CQH+)Cl3]. Mouse embryonic fibroblast (MEF) cells were treated with pre-synthesized [Zn((HO-)CQH+)Cl3] complexes and corresponding ZnCl2/(HO-)CQ mixtures and zinc uptake was determined by application of the fluorescence probe and ICP-OES measurements. Administration of pre-synthesized complexes led to higher total zinc levels than those obtained upon administration of the related zinc/(hydroxy)chloroquine mixtures. The differences in the zinc uptake between these two types of formulations were discussed in terms of different speciation and character of the complexes. The obtained results suggest that intact zinc complexes may exhibit biological effects distinct from that of the related zinc/ligand mixtures.

'Are you vaccinated? Yeah, I'm immunized': a risk orders theory analysis of celebrity COVID-19 misinformation

BACKGROUND

On 11 March 2020, COVID-19 was declared a global health pandemic by the World Health Organization (WHO). Vaccinating populations is paramount in changing the course of a pandemic. The rapid spread of (mis) and disinformation online from celebrities, politicians, and media influencers creates a corrosion of trust in public health interventions.

METHODS

Given the importance of the spread of information during a public health crisis, the current study uses risk orders theory with a constructivist grounded theory approach to analyze an episode of a popular podcast available on YouTube, titled, 'Aaron Rodgers Tells Pat McAfee His Side of Vaccine Situation.'

RESULTS

Findings illuminated three themes concerning COVID-19 medical interventions from celebrity discourse: (1) misinterpreting medical terminology; (2) conflating bodily autonomy and altruism; and (3) political ideology as an impetus for misinformation.

CONCLUSIONS

The discussion offers implications for healthcare practitioners in debunking mis- and disinformation. Foremost, lack of transparency concerning autonomy, liberty, freedom, and choice from public health experts who design messages during a public health crisis creates a space for non-medical influencers to promote pseudoscience, misinformation, and disinformation. This leads to public distrust of medical experts and confuses the public's understanding of best practices based upon standard of medical evidence and care.

Traditional Chinese Medicine as the Preventive and Therapeutic Remedy for COVID-19

The coronavirus disease 2019 (COVID-19) pandemic still has tremendous impacts on the global socio-economy and quality of living. The traditional Chinese Medicines (TCM) approach showed encouraging results during previous outbreaks of Severe Acute Respiratory Syndrome-related Coronavirus (SARS-CoV) and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). With limited treatment availability, TCM herbs and formulations could be useful to reduce COVID-19 symptoms and potential sources for discovering novel therapeutic targets. We reviewed 12 TCM herbs and formulations recommended for COVID-19 management by the National Health Commission and as National Administration of Traditional Chinese Medicine of the People's Republic of China. This article explored the Chinese national authorities' guidelines from 2003 to 2020, the scientific data in public databases for the recommended TCM remedies, and their potential mechanistic actions in COVID-19 management. Several TCM herbs and formulations could potentially benefit COVID-19 management. The recommended TCM oral preparations list includes Huoxiang zhengqi, Jinhua Qinggan, Lianhua Qingwen, and Shufeng jiedu; the recommended injection preparations comprise Xiyanping Xuebijing, Re-Du-Ning, Tanreqing, Xingnaojing, Shenfu, Shengmai, and Shenmai. TCM remedies are viable options for symptom alleviation and management of COVID-19. The current SARS-CoV-2 pandemic presents an opportunity to find novel therapeutic targets from TCM-active ingredients. Despite the recommendations in Chinese National guidelines, these remedies warrant further assessments in well-designed clinical trials to ascertain their efficacy in the treatment of COVID-19.

Epstein-Barr virus-acquired immunodeficiency in myalgic encephalomyelitis-Is it present in long COVID?

Both myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) and long COVID (LC) are characterized by similar immunological alterations, persistence of chronic viral infection, autoimmunity, chronic inflammatory state, viral reactivation, hypocortisolism, and microclot formation. They also present with similar symptoms such as asthenia, exercise intolerance, sleep disorders, cognitive dysfunction, and neurological and gastrointestinal complaints. In addition, both pathologies present Epstein-Barr virus (EBV) reactivation, indicating the possibility of this virus being the link between both pathologies. Therefore, we propose that latency and recurrent EBV reactivation could generate an acquired immunodeficiency syndrome in three steps: first, an acquired EBV immunodeficiency develops in individuals with "weak" EBV HLA-II haplotypes, which prevents the control of latency I cells. Second, ectopic lymphoid structures with EBV latency form in different tissues (including the CNS), promoting inflammatory responses and further impairment of cell-mediated immunity. Finally, immune exhaustion occurs due to chronic exposure to viral antigens, with consolidation of the disease. In the case of LC, prior to the first step, there is the possibility of previous SARS-CoV-2 infection in individuals with "weak" HLA-II haplotypes against this virus and/or EBV.

Structural, Hirshfeld surface and molecular docking studies of a new organotin(IV)-phosphoric triamide complex and an amidophosphoric acid ester proposed as possible SARS-CoV-2 and Monkeypox inhibitors

Phosphoramides and their complexes are attractive compounds due to their significant inhibiting functionality in biological medicine. In this paper, a novel organotin(IV)-phosphoramide complex (Sn(CH₃)₂Cl₂{[(3-Cl)C₆H₄NH]P(O)[NC₄H₈O]₂}₂, 1), derived from a reaction between phosphoric triamide ligand with dimethyltin dichloride, and a new amidophosphoric acid ester ([OCH₂C(CH₃)₂CH₂O]P(O)[N(CH₃)CH₂C₆H₅], 2), prepared from the condensation of a cyclic chlorophosphate reagent with N-methylbenzylamine, are structurally characterized and in silico investigated as potential SARS-CoV-2 and Monkeypox inhibitors by molecular docking simulation. Both compounds crystallize in the monoclinic crystal system with space group P2₁/c. The asymmetric unit of the complex 1 consists of one-half molecule, where Sn^IV is located on an inversion center, while the asymmetric part of 2 consists of one whole molecule. In the complex 1, the tin atom adopts a six-coordinate octahedral geometry with trans groups of (Cl)₂, (CH₃)₂ and (PO)₂ (PO = phosphoric triamide ligand). The molecular architecture consists of the N-H⋯Cl hydrogen bonds stretching as a 1D linear arrangement along the b axis with intermediate R22(12) ring motifs, whereas in the case of 2, the crystal packing is devoid of any classical hydrogen bond interaction. Furthermore, a graphical analysis by using Hirshfeld surface method identifies the most important intermolecular interactions being of the type H⋯Cl/Cl⋯H (for 1) and H⋯O/O⋯H (for 1 and 2), covering the hydrogen bond interactions N-H⋯Cl and C-H⋯O═P, respectively, which turn out to be favoured. A biological molecular docking simulation on the studied compounds provides evidence to suggest a significant inhibitory potential against SARS-COV-2 (6LU7) and Monkeypox (4QWO) especially for 6LU7 with a binding energy around -6 kcal/mol competing with current effective drugs against this virus (with a binding energy around -5 and -7 kcal/mol). It is worth noting that this report is the first case of an inhibitory potential evaluation of phosphoramide compounds on Monkeypox.

A Comparison of Etiology, Pathogenesis, Vaccinal and Antiviral Drug Development between Influenza and COVID-19

Influenza virus and coronavirus, two kinds of pathogens that exist widely in nature, are common emerging pathogens that cause respiratory tract infections in humans. In December 2019, a novel coronavirus SARS-CoV-2 emerged, causing a severe respiratory infection named COVID-19 in humans, and raising a global pandemic which has persisted in the world for almost three years. Influenza virus, a seasonally circulating respiratory pathogen, has caused four global pandemics in humans since 1918 by the emergence of novel variants. Studies have shown that there are certain similarities in transmission mode and pathogenesis between influenza and COVID-19, and vaccination and antiviral drugs are considered to have positive roles as well as several limitations in the prevention and control of both diseases. Comparative understandings would be helpful to the prevention and control of these diseases. Here, we review the study progress in the etiology, pathogenesis, vaccine and antiviral drug development for the two diseases.

Solar Photocatalysis for the Decontamination Of Water from Emerging Pharmaceutical Pollutant Chloroquine Using Nano ZnO as the Catalyst

Photo-driven advanced oxidation process (AOP) with pharmaceutical wastewater has been poorly investigated so far. This paper presents the results of an experimental investigation on the photocatalytic degradation of emerging pharmaceutical contaminant chloroquine (CLQ) in water using zinc oxide (ZnO) nanoparticles as the catalyst and solar light (SL) as the source of energy. The catalyst was characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDAX), and transmission electron microscopy (TEM). The effect of various operating parameters such as catalyst loading, the concentration of target substrate, pH, and the effect of oxidants and anions (salts) on the efficiency of degradation was tested. The degradation follows pseudo-first-order kinetics. Surprisingly, contrary to the observation in most photocatalytic studies, the degradation is more efficient under solar radiation, with 77% under solar (SL) irradiation and 65% under UV light in 60 min. The degradation leads to slow and complete COD removal through several intermediates identified by the liquid chromatography-mass spectrometry (LC-MS) technique. The results suggest the possibility of using inexpensive natural, non-renewable solar energy for the purification of CLQ-contaminated water, thereby enabling the reuse of scarce water resources.

Plant Extracts and SARS-CoV-2: Research and Applications

The recent pandemic of COVID-19 caused by the SARS-CoV-2 virus has brought upon the world an unprecedented challenge. During its acute dissemination, a rush for vaccines started, making the scientific community come together and contribute to the development of efficient therapeutic agents and vaccines. Natural products have been used as sources of individual molecules and extracts capable of inhibiting/neutralizing several microorganisms, including viruses. Natural extracts have shown effective results against the coronavirus family, when first tested in the outbreak of SARS-CoV-1, back in 2002. In this review, the relationship between natural extracts and SARS-CoV is discussed, while also providing insight into misinformation regarding the use of plants as possible therapeutic agents. Studies with plant extracts on coronaviruses are presented, as well as the main inhibition assays and trends for the future regarding the yet unknown long-lasting effects post-infection with SARS-CoV-2.

Clinical implications of COVID-19 in patients with metabolic-associated fatty liver disease

People across the world are affected by the "coronavirus disease 2019 (COVID-19)", brought on by the "SARS-CoV type-2 coronavirus". Due to its high incidence in individuals with diabetes, metabolic syndrome, and metabolic-associated fatty liver disease (MAFLD), COVID-19 has gained much attention. The metabolic syndrome's hepatic manifestation, MAFLD, carries a significant risk of type-2-diabetes. The link between the above two conditions has also drawn increasing consideration since MAFLD is intricately linked to the obesity epidemic. Independent of the metabolic syndrome, MAFLD may impact the severity of the viral infections, including COVID-19 or may even be a risk factor. An important question is whether the present COVID-19 pandemic has been fueled by the obesity and MAFLD epidemics. Many liver markers are seen elevated in COVID-19. MAFLD patients with associated comorbid conditions like obesity, cardiovascular disease, renal disease, malignancy, hypertension, and old age are prone to develop severe disease. There is an urgent need for more studies to determine the link between the two conditions and whether it might account for racial differences in the mortality and morbidity rates linked to COVID-19. The role of innate and adaptive immunity alterations in MAFLD patients may influence the severity of COVID-19. This review investigates the implications of COVID-19 on liver injury and disease severity and vice-versa. We also addressed the severity of COVID-19 in patients with prior MAFLD and its potential implications and therapeutic administration in the clinical setting.

Combating the Progression of Novel Coronavirus SARS-CoV-2 Infectious Disease: Current State and Future Prospects in Molecular Diagnostics and Drug Discovery

A highly infectious and life-threatening virus was first reported in Wuhan, China, in late 2019, and it rapidly spread all over the world. This novel virus belongs to the coronavirus family and is associated with severe acute respiratory syndrome (SARS), causing respiratory disease known as COVID-19. In March 2020, WHO has declared the COVID-19 outbreak a global pandemic. Its morbidity and mortality rates are swiftly rising day by day, with the situation becoming more severe and fatal for the comorbid population. Many COVID-19 patients are asymptomatic, but they silently spread the infection. There is a need for proper screening of infected patients to prevent the epidemic transmission of disease and for early curative interventions to reduce the risk of developing severe complications from COVID-19. To date, the diagnostic assays are of two categories, molecular detection of viral genetic material by real-time RTpolymerase chain reaction and serological test, which relies on detecting antiviral antibodies. Unfortunately, there are no effective prophylactics and therapeutics available against COVID-19. However, a few drugs have shown promising antiviral activity against it, and these presently are being referred for clinical trials, albeit FDA has issued an Emergency Use Authorization (EUA) for the emergency use of a few drugs for SARSCoV- 2 infection. This review provides an insight into current progress, challenges and future prospects of laboratory detection methods of COVID-19, and highlights the clinical stage of the major evidence-based drugs/vaccines recommended against the novel SARS-CoV-2 pandemic virus.

Structural growth of zinc oxide nanograins on carbon cloth as flexible electrochemical platform for hydroxychloroquine detection

Pharmaceutical pollution that imposes a health threat worldwide is making accurate and rapid detection crucial to prevent adverse effects. Herein, binder-free zinc oxide nanograins on carbon cloth (ZnO NGs@CC) have been synthesized hydrothermally and employed to fabricate a flexible electrochemical sensor for the quantification of hydroxychloroquine (HCQ) that is typical pharmaceutical pollution. The characteristics of ZnO NGs@CC were investigated by various in-depth electron microscopic, spectroscopic and electroanalytical approaches. Compared with the pristine CC platform, the ZnO NGs@CC platform exhibits superior electrochemical performance in detecting HCQ with a large oxidation current at a low over-potential of +0.92 V with respect to the Ag/AgCl (Sat. KCl) reference electrode. With the support of desirable characteristics, the fabricated ZnO NGs@CC-based electrochemical sensor for HCQ detection displays good performances in terms of wide sensing range (0.5-116 μM), low detection limit (0.09 μM), high sensitivity (0.279 μA μM^-1 cm^-2), and strong selectivity. By the resulting 3D hierarchical nanoarchitecture, ZnO NGs@CC has progressive structural advantages that led to its excellent electrochemical performance in sensing applications. Furthermore, the electrochemical sensor is employed to detect HCQ in biological and environmental samples and also achieves good recovery rates. Thus, the designed ZnO NGs@CC demonstrates admirable electrochemical activity toward HCQ real-time monitoring and would be an excellent electrochemical platform for HCQ sensing.

Drugs for COVID-19: An Update

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was the seventh known human coronavirus, and it was identified in Wuhan, Hubei province, China, in 2020. It caused the highly contagious disease called coronavirus disease 2019 (COVID-19), declared a global pandemic by the World Health Organization (WHO) on 11 March 2020. A great number of studies in the search of new therapies and vaccines have been carried out in these three long years, producing a series of successes; however, the need for more effective vaccines, therapies and other solutions is still being pursued. This review represents a tracking shot of the current pharmacological therapies used for the treatment of COVID-19.

Angiotensin-Converting Enzyme 2-Based Biosensing Modalities and Devices for Coronavirus Detection

Rapid and cost-effective diagnostic tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are a critical and valuable weapon for the coronavirus disease 2019 (COVID-19) pandemic response. SARS-CoV-2 invasion is primarily mediated by human angiotensin-converting enzyme 2 (hACE2). Recent developments in ACE2-based SARS-CoV-2 detection modalities accentuate the potential of this natural host-virus interaction for developing point-of-care (POC) COVID-19 diagnostic systems. Although research on harnessing ACE2 for SARS-CoV-2 detection is in its infancy, some interesting biosensing devices have been developed, showing the commercial viability of this intriguing new approach. The exquisite performance of the reported ACE2-based COVID-19 biosensors provides opportunities for researchers to develop rapid detection tools suitable for virus detection at points of entry, workplaces, or congregate scenarios in order to effectively implement pandemic control and management plans. However, to be considered as an emerging approach, the rationale for ACE2-based biosensing needs to be critically and comprehensively surveyed and discussed. Herein, we review the recent status of ACE2-based detection methods, the signal transduction principles in ACE2 biosensors and the development trend in the future. We discuss the challenges to development of ACE2-biosensors and delineate prospects for their use, along with recommended solutions and suggestions.

Accelerating space radiation countermeasure development through drug repurposing

The discovery of safe and effective radiation countermeasures (MCM) for long-duration spaceflight is challenging due to the complexity of the space radiation biology and high safety requirements. There are few if any clinically-validated molecular targets for this use case, and preclinical models have several known limitations. These challenges make the evaluation of existing FDA-approved drugs for this indication, or drug repurposing, an attractive strategy to accelerate space radiation countermeasure development. Drug repurposing offers several advantages over de novo drug discovery including established manufacturing methods, human clinical safety data, and well-understood dosing and pharmacokinetic considerations. There are limitations working with a fixed set of possible candidate compounds, but some properties of repurposed drugs can be tailored for well-defined new indications through reformulation and development of drug combinations. Drug repurposing is thus an attractive strategy for mitigating the high risks and costs of drug development and delivering new countermeasures to protect human from space radiation in long-term missions.

Pseudoscience and fraudulent products for COVID-19 management

As of now, the COVID-19 pandemic has become uncontrolled and is spreading widely throughout the world. Additionally, new variants of the mutated viral variants have been found in some countries that are more dangerous than the original strain. Even vaccines cannot produce complete protective immunity against the newer strains of SARS-CoV-2. Due to such a dreadful situation, lots of fear and depression have been created among the public. People are looking for the treatment of the disease at any cost and there is a race in the market to provide treatment and make money, whether it is effective or not! In such a condition, many fraud products, remedies, and myths have come into the market, which is falsely claimed to be effective for the disease and can harm the patients. Hence, FDA has banned such products and remedies. In this review, we have compiled all such fraudulent and pseudosciences identified for COVID-19. Currently, in the pandemic time, health agencies are approving the repurposed medicines based on the small-scale clinical data for emergency uses that become ineffective (most of the cases) after large randomized clinical studies. Proper vigilance strategies need to be defined by the regulatory agencies of the nation and routine awareness programs shall be arranged for educating the people and healthcare workers on routine updates.

Nanomaterials for Photocatalytic Degradations of Analgesic, Mucolytic and Anti-Biotic/Viral/Inflammatory Drugs Widely Used in Controlling SARS-CoV-2

The COVID-19 pandemic has been transformed into one of the main worldwide challenges, in recent years. For controlling symptoms that are caused by this disease (e.g., chills or fever, shortness of breath and/or difficulty in breathing, cough, sore throat, fatigue, headache, muscle aches, the new loss of tastes and/or smells, congestion or runny nose, nausea, vomiting and/or diarrhea), lots of medicines including analgesics, mucolytics, and anti-biotic/viral/inflammatory drugs have been frequently prescribed. As these medicines finally contaminate terrestrial and aquatic habitats by entering surface waterways through pharmaceutical production and excreting trace amounts of waste after human usage, they have negative impacts on wildlife’s health and ecosystem. Residual drugs in water have the potential to harm aquatic creatures and disrupt their food chain as well as the breeding cycle. Therefore, proper degradation of these broadly used medicines is highly crucial. In this work, the use of nanomaterials applicable in photocatalytic degradations of analgesics (e.g., acetaminophen, aspirin, ibuprofen, and naproxen), mucolytics (e.g., ambroxol), antibiotics (e.g., azithromycin and quinolones including hydroxychloroquine and chloroquine phosphate), anti-inflammatory glucocorticoids (e.g., dexamethasone and cortisone acetate), antihistamines (e.g., diphenhydramine), H2 blockers (e.g., famotidine), anthelmintics (e.g., praziquantel), and finally antivirals (e.g., ivermectin, acyclovir, lopinavir/ritonavir, favipiravir, nitazoxanide, and remdesivir) which widely used in controlling/treating the coronavirus have been reviewed and discussed.

Quantitative analysis of favipiravir and hydroxychloroquine as FDA-approved drugs for treatment of COVID-19 using synchronous spectrofluorimetry: application to pharmaceutical formulations and biological fluids

Coronavirus disease 2019 (COVID-19) is a contagious viral infection caused by coronavirus 2 (SARS-CoV-2) that causes severe acute respiratory syndrome. It has ravaged several countries and burdened many healthcare systems. As the process of authorizing a novel treatment for human use is extensive and involves multiple phases to obtain safety information and identify potential concerns. Therefore, the fastest and easiest choice was to use United States Food and Drug Administration (US FDA)-approved drugs such as favipiravir and hydroxychloroquine. For the simultaneous estimation of both medications, a simple synchronous spectrofluorimetric approach was established in which both drugs were measured at 372 and 323 nm, respectively in the presence of each other without interference at Δλ 60 nm. The effect of various experimental conditions on synchronous fluorescence intensities were thoroughly investigated and optimized. The maximum synchronous fluorescence intensities were obtained at pH 5.4 using acetate buffer (0.2 M, 0.5 ml) and ethanol as a diluent. Excellent linearity ranges were obtained using 1.0-18.0 ng/ml and 10.0-120.0 ng/ml for favipiravir and hydroxychloroquine, respectively. The approach exhibited high sensitivity with detection limits down to 0.25 ng/ml and 1.52 ng/ml and quantitation limits down to 0.77 ng/ml and 4.62 ng/ml, respectively. Spiking human plasma samples with the studied drugs yielded high % recoveries, allowing a significant bioanalytical application. Moreover, the method was validated according to International Conference on Harmonization guidelines and further applied to commercial pharmaceutical preparations with good results.

Redox aspects of cytotoxicity and anti-neuroinflammatory profile of chloroquine and hydroxychloroquine in serum-starved BV-2 microglia

Chloroquine (CQ) and hydroxychloroquine (HCQ) have long been used worldwide to treat and prevent human malarias. However, these 4-aminoquinolines have also shown promising potential in treating chronic illnesses with an inflammatory component, including neurological diseases. Given the current demand for serum avoidance during pharmacological testing and modeling of some pathologies, we compared cytotoxicities of CQ and HCQ in both serum-deprived and -fed murine BV-2 microglia. Furthermore, we assessed the anti-neuroinflammatory potential of both compounds in serum-deprived cells. Under both conditions, CQ showed higher cytotoxicity than HCQ. However, the comparable MTT-assay-derived data measured under different serum conditions were associated with disparate cytotoxic mechanisms of CQ and HCQ. In particular, under serum starvation, CQ mildly enhanced secondary ROS, mitochondrial hyperpolarization, and decreased phagocytosis. However, CQ promoted G1 phase cell cycle arrest and mitochondrial depolarization in serum-fed cells. Under both conditions, CQ fostered early apoptosis. Additionally, we confirmed that both compounds could exert anti-inflammatory effects in microglia through interference with MAPK signaling under nutrient-deprivation-related stress. Nevertheless, unlike HCQ, CQ is more likely to exaggerate intracellular prooxidant processes in activated starved microglia, which are inefficiently buffered by Nrf2/HO-1 signaling pathway activation. These outcomes also show HCQ as a promising anti-neuroinflammatory drug devoid of CQ-mediated cytotoxicity.

Approaches to prioritising primary health research: a scoping review

Objective

To systematically identify and describe approaches to prioritise primary research topics in any health-related area.

Methods

We searched Medline and CINAHL databases and Google Scholar. Teams of two reviewers screened studies and extracted data in duplicate and independently. We synthesised the information across the included approaches by developing common categorisation of relevant concepts.

Results

Of 44 392 citations, 30 articles reporting on 25 approaches were included, addressing the following fields: health in general (n=9), clinical (n=10), health policy and systems (n=10), public health (n=6) and health service research (n=5) (10 addressed more than 1 field). The approaches proposed the following aspects to be addressed in the prioritisation process: situation analysis/ environmental scan, methods for generation of initial list of topics, use of prioritisation criteria, stakeholder engagement, ranking process/technique, dissemination and implementation, revision and appeal mechanism, and monitoring and evaluation. Twenty-two approaches proposed involving stakeholders in the priority setting process. The most commonly proposed stakeholder category was ‘researchers/academia’ (n=17, 77%) followed by ‘healthcare providers’ (n=16, 73%). Fifteen of the approaches proposed a list of criteria for determining research priorities. We developed a common framework of 28 prioritisation criteria clustered into nine domains. The criterion most frequently mentioned by the identified approaches was ‘health burden’ (n=12, 80%), followed by ‘availability of resources’ (n=11, 73%).

Conclusion

We identified and described 25 prioritisation approaches for primary research topics in any health-related area. Findings highlight the need for greater participation of potential users (eg, policy-makers and the general public) and incorporation of equity as part of the prioritisation process. Findings can guide the work of researchers, policy-makers and funders seeking to conduct or fund primary health research. More importantly, the findings should be used to enhance a more coordinated approach to prioritising health research to inform decision making at all levels.

The relationship between hydroxychloroquine plasma concentration and COVID-19 outcomes in rheumatoid arthritis patients in Saudi Arabia

Background

The drug hydroxychloroquine (HCQ) is widely used to treat rheumatoid arthritis (RA) and has been repurposed for the treatment of COVID-19. This study aims to determine whether HCQ concentration levels in individuals with RA alter the incidence of COVID-19 or its complications.

Methods

We collected plasma samples from 13 individuals with confirmed rheumatoid arthritis (RA) to measure HCQ concentration levels. The study included individuals at least 18 years old who had been taking HCQ for at least six months at daily doses ranging from 200 to 400 mg.

Results

The study enrolled a total of 13 RA patients. All patients were chronic HCQ users. Among the 13 patients, 7 patients were receiving HCQ at a dose of 200 mg per day, and 6 patients were receiving HCQ at a dose of 400 mg per day. COVID-19 confirmed cases accounted for approximately 46% of all patients. Half of the infected patients (n = 3) were taking a daily dose of 200 mg daily, while the other half were taking 400 mg daily. COVID-19 symptoms ranged from mild to moderate, and the intensity of the symptoms was not severe enough to necessitate hospitalization. COVID-19 symptoms in RA patients included headache, fever, fatigue, dry cough, and loss of taste or smell.

Conclusions

Our findings indicated that there was no correlation between HCQ concentrations in rheumatoid arthritis patients and the occurrence of COVID-19 or its complications.

Systematic Review of the Common Pathophysiological Mechanisms in COVID-19 and Neurodegeneration: The Role of Bioactive Compounds and Natural Antioxidants

The novel coronavirus (2019-nCoVCOVID-19) belongs to the Beta coronavirus family, which contains MERS-CoV (Middle East respiratory syndrome coronavirus) and SARS-CoV (severe acute respiratory syndrome coronavirus). SARS-CoV-2 activates the innate immune system, thereby activating the inflammatory mechanism, causing the release of inflammatory cytokines. Moreover, it has been suggested that COVID-19 may penetrate the central nervous system, and release inflammatory cytokines in the brains, inducing neuroinflammation and neurodegeneration. Several links connect COVID-19 with Alzheimer’s disease (AD), such as elevated oxidative stress, uncontrolled release of the inflammatory cytokines, and mitochondrial apoptosis. There are severe concerns that excessive immune cell activation in COVID-19 may aggravate the neurodegeneration and amyloid-beta pathology of AD. Here, we have collected the evidence, showing the links between the two diseases. The focus has been made to collect the information on the activation of the inflammation, its contributors, and shared therapeutic targets. Furthermore, we have given future perspectives, research gaps, and overlapping pathological bases of the two diseases. Lastly, we have given the short touch to the drugs that have equally shown rescuing effects against both diseases. Although there is limited information available regarding the exact links between COVID-19 and neuroinflammation, we have insight into the pathological contributors of the diseases. Based on the shared pathological features and therapeutic targets, we hypothesize that the activation of the immune system may induce neurological disorders by triggering oxidative stress and neuroinflammation.

'A disease like any other' traditional, complementary and alternative medicine use and perspectives in the context of COVID-19 among the Congolese community in Belgium

BACKGROUND

As a hard-hit area during the COVID-19 pandemic, Belgium knew the highest mortality among people from sub-Saharan African descent, compared to any other group living in the country. After migration, people often maintain traditional perceptions and habits regarding health and healthcare, resulting in a high prevalence of traditional, complementary and alternative medicine use among different migrant communities in northern urban settings. Despite being the largest community of sub-Saharan African descent in Belgium, little is known on ethnobotanical practices of the Belgian Congolese community. We therefore conducted an exploratory study on the use of medicinal plants in the context of COVID-19 and perceptions on this new disease among members of the Congolese community in Belgium.

METHODS

We conducted 16 in-depth semi-structured interviews with people of Congolese descent currently living in Belgium. Participants were selected using purposive sampling. Medicinal plant use in the context of COVID-19 was recorded through free-listing. Data on narratives, ideas and perceptions on the origin, cause/aetiology and overall measures against COVID-19 (including vaccination) were collected. Interview transcripts were analysed using thematic analysis.

RESULTS

Four overarching themes emerged from our data. Firstly, participants perceived the representation of the severity of COVID-19 by the Belgian media and government-and by extend by all governmental agencies in the global north-as exaggerated. As a result, traditional and complementary treatments were seen as feasible options to treat symptoms of the disease. Fifteen forms of traditional, complementary and alternative medicine were documented, of which thirteen were plants. Participants seem to fold back on their Congolese identity and traditional knowledge in seeking coping strategies to deal with the COVID-19 pandemic. Finally, institutional postcolonial distrust did not only seem to lead to distrust in official messages on the COVID-19 pandemic but also to feelings of vaccination hesitancy.

CONCLUSION

In the context of the COVID-19 pandemic, participants in our study retreated to, reshaped and adapted traditional and culture-bound knowledge. This study suggests that the fragile and sensitive relationship between sub-Saharan African migrant groups and other social/ethnic groups in Belgium might play a role in their sensitivity to health-threatening situations, such as the COVID-19 pandemic.

Effective degradation of COVID-19 related drugs by biochar-supported red mud catalyst activated persulfate process: Mechanism and pathway

With the global spread of the COVID-19 pandemic, the water pollution caused by extensive production and application of COVID-19 related drugs has aroused growing attention. Herein, a novel biochar-supported red mud catalyst (RM-BC) containing abundant free hydroxyl groups was synthesized. The RM-BC activated persulfate process was firstly put forward to degrade COVID-19 related drugs, including arbidol (ARB), chloroquine phosphate, hydroxychloroquine sulfate, and acyclovir. Highly effective removal of these pharmaceuticals was achieved and even 100% of ARB was removed within 12 min at optimum conditions. Mechanism study indicated that SO₄ ^•- and HO^• were the predominant radicals, and these radicals were responsible for the formation of DMPOX in electron spin resonance experiments. Fe species (Fe⁰ and Fe₃O₄) and oxygen-containing functional groups in RM-BC played crucial roles in the elimination of ARB. Effects of degradation conditions and several common water matrices were also investigated. Finally, the degradation products of ARB were identified by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and possible degradation pathways were proposed. This study demonstrated that RM-BC/PS system would have great potential for the removal of COVID-19 related drug residues in water by the catalyst synthesized from the solid waste.

Severity factors in Algerian patients hospitalized for COVID-19

INTRODUCTION

Determining the profile of COVID-19 patients with low pulsed hemoglobin saturation in oxygen (SpO2) could help clinicians identify those with a poor prognosis.

AIM

To identify and to compare the clinical, biological and radiological data of Algerian patients hospitalized for COVID-19 and divided according to the SpO2 measured at admission, at rest, and in ambient air.

METHODS

A prospective study was carried out on Algerian patients hospitalized for COVID-19 during the period from March 9 to April 30, 2020. The general characteristics of the patients and the clinical, biological and radiological data were determined.

RESULTS

86 patients were included in the study [G1: SpO2 >95% (n=51) and G2: SpO2 ≤95% (n=35)]. Compared to G1, G2 was older (48±14 vs. 61±12 years, p=0.0001), included more patients aged ≥ 50 years (37.2 vs. 80.0%, p=0.0001), having an arterial-hypertension (21.6 vs. 45.7%, p=0.0180), a cancer (0.0 vs. 14.3%, p=0.0054), an anemia (25.6 vs. 56.3%, p=0.0069), a leukocytosis (4.7 vs. 21.9%, p=0.0236), a biological inflammatory syndrome (82.5 vs. 100%, p=0.0142), a hyper-uremia (7.0 vs. 37.5%, p=0.0185), a hyper-creatininaemia (4.7 vs. 18.8%, p=0.0356), a tissue damage (41.0 vs. 66.7%, p=0.0341), a diffuse ground-glass opacity (52.0 vs. 71.4%, p=0.0397), band condensations (30.0 vs. 54.3%, p=0.0244), a severe extension (2.0 vs. 25.7%, p=0.0008), and included fewer patients who complained from diarrhea (49.0 vs. 22.9%, p=0.0145), having a nodular ground-glass (66.0 vs. 40.0%, p=0.0177) and a slight extension (78.0 vs. 40.0%, p=0.0004).

CONCLUSION

Criteria associated with low SpO2 in hospitalized COVID-19 patients were advanced age, a history of arterial-hypertension and cancer, high frequencies of certain biological abnormalities or radiological signs. The diarrhea symptom, the radiological appearance of nodular ground glass, and a slight extension of the radiological lesions appear as protective elements.

On the Origin of Neutrophil Extracellular Traps in COVID-19

Despite ongoing vaccination COVID-19 is a global healthcare problem because of the lack of an effective targeted therapy. In severe COVID-19 manifesting as acute respiratory distress syndrome, uncontrolled innate immune system activation results in cytokine deregulation, damage-associated molecular patterns release upon tissue damage and high occurrence of thrombotic events. These pathomechanisms are linked to neutrophil function and dysfunction, particularly increased formation of neutrophil extracellular traps (NETs). While the association of NETs and severity of COVID-19 has been shown and proved, the causes of NETs formation are unclear. The aim of this review is to summarize potential inducers of NETs formation in severe COVID-19 and to discuss potential treatment options targeting NETs formation of removal.

Repurposing the drug, ivermectin, in COVID-19: toxicological points of view

The global COVID-19 pandemic has affected the world’s population by causing changes in behavior, such as social distancing, masking, restricting people’s movement, and evaluating existing medication as potential therapies. Many pre-existing medications such as tocilizumab, ivermectin, colchicine, interferon, and steroids have been evaluated for being repurposed to use for the treatment of COVID-19. None of these agents have been effective except for steroids and, to a lesser degree, tocilizumab. Ivermectin has been one of the suggested repurposed medications which exhibit an in vitro inhibitory activity on SARS-CoV-2 replication. The most recommended dose of ivermectin for the treatment of COVID-19 is 150–200 µg/kg twice daily. As ivermectin adoption for COVID-19 increased, the Food and Drug Administration (FDA) issued a warning on its use during the pandemic. However, the drug remains of interest to clinicians and has shown some promise in observational studies. This narrative reviews the toxicological profile and some potential therapeutic effects of ivermectin. Based on the current dose recommendation, ivermectin appears to be safe with minimum side effects. However, serious questions remain about the effectiveness of this drug in the treatment of patients with COVID-19.

Integrative In Silico Investigation Reveals the Host-Virus Interactions in Repurposed Drugs Against SARS-CoV-2

The ongoing COVID-19 outbreak have posed a significant threat to public health worldwide. Recently Toll-like receptor (TLR) has been proposed to be the drug target of SARS-CoV-2 treatment, the specificity and efficacy of such treatments remain unknown. In the present study we performed the investigation of repurposed drugs via a framework comprising of Search Tool for Interacting Chemicals (STITCH), Kyoto Encyclopedia of Genes and Genomes (KEGG), molecular docking, and virus-host-drug interactome mapping. Chloroquine (CQ) and hydroxychloroquine (HCQ) were utilized as probes to explore the interaction network that is linked to SARS-CoV-2. 47 drug targets were shown to be overlapped with SARS-CoV-2 network and were enriched in TLR signaling pathway. Molecular docking analysis and molecular dynamics simulation determined the direct binding affinity of TLR9 to CQ and HCQ. Furthermore, we established SARS-CoV-2-human-drug protein interaction map and identified the axis of TLR9-ERC1-Nsp13 and TLR9-RIPK1-Nsp12. Therefore, the elucidation of the interactions of SARS-CoV-2 with TLR9 axis will not only provide pivotal insights into SARS-CoV-2 infection and pathogenesis but also improve the treatment against COVID-19.

Current challenges in different approaches to control COVID-19: a comprehensive review

BACKGROUND

The World Health Organization declared the outbreak of the novel coronavirus (COVID-19) as a global health emergency on January 30, 2020, and as a pandemic disease on March 11, 2020. This review highlights the international situation, risk factors, and related protections to be taken as prerequisite measures and probable treatment options for the COVID-19-infected population in the current scenario.

MAIN TEXT

The SARS-CoV-2 viruses and their variants caused mild-to-severe respiratory tract infection and used airborne pathways as a way of contagion. Human-to-human transmission led to an exponential growth in the rise in the number of cases making it a real burden to immobilize the rapid spread of the virus while asymptomatic patients created ambiguity for confirmation in the community. It was clear from the case studies of patients that most of them were asymptomatic but still vulnerable to the people around, and hence, in a flash, many countries around the globe went into a complete lockdown, influencing the economy and thrashing industrial outputs. On the other hand, numerous researches were made to counteract the spread through studies in antiviral therapy, immune-based therapy, vaccination development, and natural remedies.

CONCLUSION

Although exploration for a specific drug required for the COVID-19 treatment is under extensive research worldwide and some of them are in clinical trial now. Virtual drug library screening is one of the current techniques for repurposing accessible compounds. This review could provide beneficial information about the potential current and future treatment strategies to treat the pandemic COVID-19 infection.

Assessment of proarrhythmogenic risk for chloroquine and hydroxychloroquine using the CiPA concept

Chloroquine and hydroxychloroquine have been proposed recently as therapy for SARS-CoV-2-infected patients, but during 3 months of extensive use concerns were raised related to their clinical effectiveness and arrhythmogenic risk. Therefore, we estimated for these compounds several proarrhythmogenic risk predictors according to the Comprehensive in vitro Proarrhythmia Assay (CiPA) paradigm. Experiments were performed with either CytoPatch™2 automated or manual patch-clamp setups on HEK293T cells stably or transiently transfected with hERG1, hNav1.5, hKir2.1, hKv7.1+hMinK, and on Pluricyte® cardiomyocytes (Ncardia), using physiological solutions. Dose-response plots of hERG1 inhibition fitted with Hill functions yielded IC50 values in the low micromolar range for both compounds. We found hyperpolarizing shifts of tens of mV, larger for chloroquine, in the voltage-dependent activation but not inactivation, as well as a voltage-dependent block of hERG current, larger at positive potentials. We also found inhibitory effects on peak and late I_Na and on I_K1, with IC50 of tens of μM and larger for chloroquine. The two compounds, tested on Pluricyte® cardiomyocytes using the β-escin-perforated method, inhibited I_Kr, I_CaL, I_{Na peak}, but had no effect on I_f. In current-clamp they caused action potential prolongation. Our data and those from literature for I_to were used to compute proarrhythmogenic risk predictors B_net (Mistry HB, 2018) and Q_net (Dutta S et al., 2017), with hERG1 blocking/unblocking rates estimated from time constants of fractional block. Although the two antimalarials are successfully used in autoimmune diseases, and chloroquine may be effective in atrial fibrillation, assays place these drugs in the intermediate proarrhythmogenic risk group.

Investigation of Thiocarbamates as Potential Inhibitors of the SARS-CoV-2 Mpro

In the present study we tested, using the microscale thermophoresis technique, a small library of thionocarbamates, thiolocarbamates, sulfide and disulfide as potential lead compounds for SARS-CoV-2 Mpro drug design. The successfully identified binder is a representative of the thionocarbamates group with a high potential for future modifications aiming for higher affinity and solubility. The experimental analysis was extended by computational studies that show insufficient accuracy of the simplest and widely applied approaches and underline the necessity of applying more advanced methods to properly evaluate the affinity of potential SARS-CoV-2 Mpro binders.

Role of endolysosome function in iron metabolism and brain carcinogenesis

Iron, the most abundant metal in human brain, is an essential microelement that regulates numerous cellular mechanisms. Some key physiological roles of iron include oxidative phosphorylation and ATP production, embryonic neuronal development, formation of iron-sulfur clusters, and the regulation of enzymes involved in DNA synthesis and repair. Because of its physiological and pathological importance, iron homeostasis must be tightly regulated by balancing its uptake, transport, and storage. Endosomes and lysosomes (endolysosomes) are acidic organelles known to contain readily releasable stores of various cations including iron and other metals. Increased levels of ferrous (Fe2+) iron can generate reactive oxygen species (ROS) via Fenton chemistry reactions and these increases can damage mitochondria and genomic DNA as well as promote carcinogenesis. Accumulation of iron in the brain has been linked with aging, diet, disease, and cerebral hemorrhage. Further, deregulation of brain iron metabolism has been implicated in carcinogenesis and may be a contributing factor to the increased incidence of brain tumors around the world. Here, we provide insight into mechanisms by which iron accumulation in endolysosomes is altered by pH and lysosome membrane permeabilization. Such events generate excess ROS resulting in mitochondrial DNA damage, fission, and dysfunction, as well as DNA oxidative damage in the nucleus; all of which promote carcinogenesis. A better understanding of the roles that endolysosome iron plays in carcinogenesis may help better inform the development of strategic therapeutic options for cancer treatment and prevention.

Determination of antimalarial drugs in pharmaceutical formulations and human blood by liquid chromatography: a review

Malaria is a life-threatening disease being treated by oral medication. This is the best treatment to reduce morbidity and mortality, prevent disease progression to the most severe form, lower the transmission of the disease and hinder the appearance of strains resistant to antimalarials. According to the World Health Organization, the most common antimalarial drugs are chloroquine, primaquine, mefloquine, lumefantrine, artemether, and artesunate in single dosage forms or fixed-dose combination. Within this context, the present review aims to show the evolution of different analytical methods that have been applied to the determination of these antimalarial drugs in pharmaceutical formulations and human blood by liquid chromatography in the last 10 years, along with statistical analyses of the methods.

Insight into the emerging role of SARS-CoV-2 nonstructural and accessory proteins in modulation of multiple mechanisms of host innate defense

Coronavirus disease-19 (COVID-19) is an extremely infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that has become a major global health concern. The induction of a coordinated immune response is crucial to the elimination of any pathogenic infection. However, SARS-CoV-2 can modulate the host immune system to favor viral adaptation and persistence within the host. The virus can counteract type I interferon (IFN-I) production, attenuating IFN-I signaling pathway activation and disrupting antigen presentation. Simultaneously, SARS-CoV-2 infection can enhance apoptosis and the production of inflammatory mediators, which ultimately results in increased disease severity. SARS-CoV-2 produces an array of effector molecules, including nonstructural proteins (NSPs) and open-reading frames (ORFs) accessory proteins. We describe the complex molecular interplay of SARS-CoV-2 NSPs and accessory proteins with the host's signaling mediating immune evasion in the current review. In addition, the crucial role played by immunomodulation therapy to address immune evasion is discussed. Thus, the current review can provide new directions for the development of vaccines and specific therapies.

The COVID-19 Vaccination Strategy in Brazil-A Case Study

Brazil is among the countries which have faced two devastating infection waves of COVID-19 in the past year. Despite the fact the country has one of the world's leading immunization programs, Brazil only slowly established a national COVID-19 vaccination strategy and campaign. This case study is based on an integrative review of primary and secondary literature sources. Different search strategies on Medline and Google Scholar were performed for the case presentation, for the management and outcome of the COVID-19 outbreak and for the state of the COVID-19 vaccination program. Official documents from the Brazilian Ministry of Health, the website of the World Health Organization and pharmaceutical companies were also reviewed. Searches were limited to English, French, German, Portuguese and Spanish. This article describes the Brazilian COVID-19 vaccination campaign and the drivers and barriers to its implementation; and evaluates further investigations needed to have a conclusive overview over the constantly evolving situation. Healthcare inequalities, which were widened during the pandemic, a lack of coordination at the federal level, the absence of federal government support for scientific research and the lack of endorsement and commitment to the mitigation of the COVID-19 pandemic set the country's COVID-19 vaccination campaign off to a challenging start. However, Brazil had a well-developed primary care system and national vaccination program prior to the pandemic, which are both important facilitators. At the time of writing, six vaccines are currently available in the country, and the program is advancing. The scientific community needs to continue to investigate the country's vaccination strategy and its implementation to make sure that maximum effort is undertaken for the health of the Brazilian population.

Anti-SARS-CoV-2 Strategies and the Potential Role of miRNA in the Assessment of COVID-19 Morbidity, Recurrence, and Therapy

Recently, we have experienced a serious pandemic. Despite significant technological advances in molecular technologies, it is very challenging to slow down the infection spread. It appeared that due to globalization, SARS-CoV-2 spread easily and adapted to new environments or geographical or weather zones. Additionally, new variants are emerging that show different infection potential and clinical outcomes. On the other hand, we have some experience with other pandemics and some solutions in virus elimination that could be adapted. This is of high importance since, as the latest reports demonstrate, vaccine technology might not follow the new, mutated virus outbreaks. Thus, identification of novel strategies and markers or diagnostic methods is highly necessary. For this reason, we present some of the latest views on SARS-CoV-2/COVID-19 therapeutic strategies and raise a solution based on miRNA. We believe that in the face of the rapidly increasing global situation and based on analogical studies of other viruses, the possibility of using the biological potential of miRNA technology is very promising. It could be used as a promising diagnostic and prognostic factor, as well as a therapeutic target and tool.

Computational studies reveal Fluorine based quinolines to be potent inhibitors for proteins involved in SARS-CoV-2 assembly

World is witnessing one of the worst pandemics of this century caused by SARS-CoV-2 virus which has affected millions of individuals. Despite rapid efforts to develop vaccines and drugs for COVID-19, the disease is still not under control. Chloroquine (CQ) and Hydroxychloroquine (HCQ) are two very promising inhibitors which have shown positive effect in combating the disease in preliminary experimental studies, but their use was reduced due to severe side-effects. Here, we performed a theoretical investigation of the same by studying the binding of the molecules with SARS-COV-2 Spike protein, the complex formed by Spike and ACE2 human receptor and a human serine protease TMPRSS2 which aids in cleavage of the Spike protein to initiate the viral activation in the body. Both the molecules had shown very good docking energies in the range of -6kcal/mol. Subsequently, we did a high throughput screening for other potential quinoline candidates which could be used as inhibitors. From the large pool of ligand candidates, we shortlisted the top three ligands (binding energy -8kcal/mol). We tested the stability of the docked complexes by running Molecular Dynamics (MD) simulations where we observed the stability of the quinoline analogues with the Spike-ACE2 and TMPRSS2 nevertheless the quinolines were not stable with the Spike protein alone. Thus, although the inhibitors bond very well with the protein molecules their intrinsic binding affinity depends on the protein dynamics. Moreover, the quinolines were stable when bound to electronegative pockets of Spike-ACE2 or TMPRSS2 but not with Viral Spike protein. We also observed that a Fluoride based compound: 3-[3-(Trifluoromethyl)phenyl]quinoline helps the inhibitor to bind with both Spike-ACE2 and TMPRSS2 with equal probability. The molecular details presented in this study would be very useful for developing quinoline based drugs for COVID-19 treatment.

Chloroquine and pyrimethamine inhibit the replication of human respiratory syncytial virus A

Human respiratory syncytial virus (hRSV) is a major cause of respiratory illness in young children and can cause severe infections in the elderly or in immunocompromised adults. To date, there is no vaccine to prevent hRSV infections, and disease management is limited to preventive care by palivizumab in infants and supportive care for adults. Intervention with small-molecule antivirals specific for hRSV represents a good alternative, but no such compounds are currently approved. The investigation of existing drugs for new therapeutic purposes (drug repositioning) can be a faster approach to address this issue. In this study, we show that chloroquine and pyrimethamine inhibit the replication of human respiratory syncytial virus A (long strain) and synergistically increase the anti-replicative effect of ribavirin in cellulo. Moreover, chloroquine, but not pyrimethamine, inhibits hRSV replication in the mouse model. Our results show that chloroquine can potentially be an interesting compound for treatment of hRSV infection in monotherapy or in combination with other antivirals.

Efficacy and sustainability of natural products in COVID-19 treatment development: opportunities and challenges in using agro-industrial waste from Citrus and apple

Natural products have been used in the treatment of illnesses throughout the history of humankind. Exploitation of bioactive compounds from natural sources can aid in the discovery of new drugs, provide the scaffold of new medicines. In the face of challenging diseases, such as the COVID-19 pandemic, for which there was no effective treatment, nature could offer insights as to novel therapeutic options for control measures. However, the environmental impact and supply chain of bioactive production must be carefully evaluated to ensure the detrimental effects will not outweigh the potential benefits gained. History has already proven that highly bioactive compounds can be rare and not suitable for medicinal exploitation; therefore, the sustainability must be accessed before expensive, time-demanding, and large trials can be initialized. A sustainable option to readily produce a phytotherapy with minimal environmental stress is the use of agro-industry wastes, a by-product produced in high quantities. In this review we evaluate the sustainability issues associated with the production of phytotherapy as a readily available tool for pandemic control.

Kidney injury in COVID-19 patients, drug development and their renal complications: Review study

Since December 2019, the world was encountered a new disease called coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although SARS-CoV-2 initially causes lung damage, it also affects many other organs, including the kidneys, and on average, 5–23% of people with COVID-19 develop the symptoms of acute kidney injury (AKI), including elevated blood creatinine and urea, hematuria, proteinuria, and histopathological damages. The exact mechanism is unknown, but the researchers believe that SARS-CoV-2 directly and indirectly affects the kidneys. The direct pathway is by binding the virus to ACE2 receptor in the kidney, damage to cells, the renin-angiotensin system disturbances, activating coagulation pathways, and damaging the renal vascular endothelium. The initial evidence from studying the kidney tissue in postmortem patients is more in favor of the direct pathway. The indirect pathway is created by increased cytokines and cytokine storm, sepsis, circulatory disturbances, hypoxemia, as well as using the nephrotoxic drugs. Using renal tissue biopsy and autopsy in the patients with COVID-19, recent studies found evidence for a predominant indirect pathway in AKI induction by SARS-CoV-2. Besides, some studies showed that the degree of acute tubular injury (ATI) in autopsies from COVID-19 victims is milder compared to AKI degree. We review the mechanism of AKI induction and the renal side effects of the most common drugs used to treat COVID-19 after the overview of the latest findings on SARS-CoV-2 pathogenicity.

Synthesis of modified beta bismuth oxide by titanium oxide and highly efficient solar photocatalytic properties on hydroxychloroquine degradation and pathways

With the outbreak of coronavirus pandemic the use of Hydroxychloroquine increased. These compounds have harmful effects on the environment, such as generation of antibiotic-resistant bacteria; therefore, their degradation has been considered as one of the environmental challenges. The purpose of this research is to synthesize heterogeneous structure of TiO₂/β-Bi₂O₃ by hydrothermal method for solar degradation of Hydroxychloroquine. Then, the accurate characteristics of the synthesized samples were investigated by XRD, FESEM, TEM, XPS, UV–vis (DRS), and BET surface analyzer. Photocatalytic degradation of Hydroxychloroquine was studied under sunlight, and it was found that the visible light absorption of TiO₂ photocatalyst by mixing β-Bi₂O₃ nanoparticles was greatly increased and 91.89% of the degradation was obtained in 120 min of photocatalytic reaction. This improvement can be attributed to the increased specific surface area, efficient charge transfer, and reduced electron-hole recombination with the β-Bi₂O₃ compound. Kinetic studies also reacted to follow pseudo-first-order kinetics. Also, demonstrated high stability and recyclability for nanoparticles, so that after 6 cycles of using the catalyst in take, 70.59% degradation was performed. According to the results, the excellent photocatalytic degradation activity demonstrated by the TiO₂/β-Bi₂O₃, therefore, it is a potential candidate for the process of removing other organic contaminants from aqueous solutions.

Understanding the Molecular Biology of SARS-CoV-2 and the COVID-19 Pandemic: A Review

Coronaviruses are named after the crown-like spike proteins on their surface. In the 21st century, three coronaviruses, namely severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), SARS-CoV, and Middle East respiratory syndrome related coronavirus (MERS-CoV), have emerged in the human population, presumably evolving from pathogens infecting other animals. Coronaviruses are enveloped viruses responsible for 15-30% of the atypical pneumonia cases in humans worldwide. The current coronavirus disease 2019 (COVID-19) pandemic is caused by the newest SARS virus, SARS-CoV-2, an enveloped, positive-sense, single-stranded RNA betacoronavirus of the family Coronaviridae. As of April 2021, the World Health Organization has reported more than 3 million deaths from COVID-19 and more than 140 million people have been infected with the virus, thereby making it the worst SARS pandemic of all time. Here, I review the current understanding of the molecular biology of coronaviruses and their host interactions, bringing together knowledge of the infection process to aid in the development of therapeutic drugs and/or vaccines against SARS-CoV-2. I also briefly overview the current situation of available treatments, vaccinations, and emerging strains.

Opinion and uptake of chloroquine for treatment of COVID-19 during the mandatory lockdown in the sub-Saharan African region

BACKGROUND

As the search for effective treatment of coronavirus disease 2019 (COVID-19) infection continues, the public opinion around the potential use of chloroquine (CQ) in treating COVID-19 remains mixed.

AIM

To examine opinion and uptake of CQ for treating COVID-19 in the sub-Saharan African (SSA) region.

SETTING

This study was conducted through an online survey software titled SurveyMonkey.

METHODS

Anonymous online survey of 1829 SSA countries was conducted during the lockdown period using Facebook, WhatsApp and authors' networks. Opinion and uptake of CQ for COVID-19 treatment were assessed using multivariate analyses.

RESULTS

About 14% of respondents believed that CQ could treat COVID-19 and of which, 3.2% took CQ for COVID-19 treatment. Multivariate analyses revealed that respondents from Central (adjusted odds ratios [aOR]: 2.54, 95% confidence interval [CI] 1.43, 4.43) and West Africa (aOR: 1.79, 95% CI 1.15, 2.88) had higher odds of believing that CQ could treat COVID-19. Respondents from East Africa reported higher odds for uptake of CQ for COVID-19 than Central, Western and Southern Africans. Knowledge of the disease and compliance with the public health advice were associated with both belief and uptake of CQ for COVID-19 treatment.

CONCLUSION

Central and West African respondents were more likely to believe in CQ as a treatment for COVID-19 whilst the uptake of the medication during the pandemic was higher amongst East Africans. Future intervention discouraging the unsupervised use of CQ should target respondents from Central, West and East African regions.

Quadruple isotope dilution gas chromatography-mass spectrometry after simultaneous derivatization and spraying based fine droplet formation liquid phase microextraction method for the accurate and sensitive quantification of chloroquine phosphate in human serum, urine and saliva samples at trace levels

This study presents an accurate and precise analytical strategy for the determination of chloroquine phosphate at trace levels in human body fluids (urine, serum, and saliva). Simultaneous derivatization-spraying based fine droplet formation-liquid phase microextraction (SD-SFDF-LPME) method was used to derivatize and preconcentrate the analyte prior to gas chromatography-mass spectrometry (GC-MS) measurements. Acetic anhydride was employed as derivatizing agent in this study. After optimizing the SD-SFDF-LPME method, the limit of detection (LOD) and limit of quantitation (LOQ) were found to be 0.16 and 0.53 mg/kg, respectively. Quadruple isotope dilution (ID⁴) was coupled to the SD-SFDF-LPME method in order to alleviate matrix effects and promote accuracy/precision of the method. Chloroquine acetamide-d3 was firstly synthesized in our research laboratory and used as the isotopic analogue of the analyte in the ID⁴ experiments. Superior percent recovery results (99.4% - 101.0%) with low standard deviation values were obtained for the spiked samples. This validated the developed SD-SFDF-LPME-ID⁴-GC-MS method as highly accurate and precise for the determination of chloroquine phosphate at trace levels. In addition, the isotopic analogue of the analyte was obtained via the acetamide derivative of the analyte, which is an alternative to obtain isotopic analogues of organic compounds that are not accessible or commercially available.

Antiviral treatment selection for SARS-CoV-2 pneumonia

INTRODUCTION

Therapy of coronavirus disease 2019 (COVID-19) involves evolving algorithms that include drugs aimed at reducing disease progression by counteracting two different, but intertwined processes: (i) the damage caused by the virus (with antivirals); (ii) the damage caused by a dysregulated host response (with immunomodulatory agents).

AREAS COVERED

Herein, we discuss the available evidence on the efficacy and safety of antiviral agents employed over the past months for the treatment of COVID-19, and the reasons to be considered for antiviral selection.

EXPERT OPINION

The available evidence from randomized controlled trials (RCT) currently discourages the use of lopinavir/ritonavir, hydroxychloroquine, and interferons, which did not show improved efficacy compared to standard care or placebo. Regarding remdesivir, the current body of evidence may conditionally support its use in COVID-19 patients requiring oxygen supplementation but still not requiring invasive mechanical ventilation. Finally, neutralizing monoclonal antibodies have been proven efficacious in reducing the risk of severe disease development if administered early in the course of the disease to patients at risk of progression. The results of the ongoing RCT will certainly be crucial to further improve our understanding of the optimal place in therapy of antiviral agents for COVID-19.

Epidemiological and Clinical Characteristics of COVID-19: A Retrospective Multi-Center Study in Pakistan

The emergence of a pathogen responsible for a mysterious respiratory disease was identified in China and later called a novel coronavirus. This disease was named COVID-19. The present study seeks to determine the epidemiological and clinical characteristics of COVID-19 in Pakistan. This report will exhibit a linkage between epidemiology and clinical aspects which in turn can be helpful to prevent the transmission of the virus in Pakistan. A retrospective, multiple center study was performed by collecting the data from patients' with their demographics, epidemiological status, history of co-morbid conditions, and clinical manifestations of the disease. The data was collected from 31 public-sector and 2 private hospitals across Pakistan by on-field healthcare workers. A Chi-square test was applied to assess the relationship between categorical data entries. A total of 194 medical records were examined. The median age of these patients was found to be 34 years. A total of 53.6% active cases were present including 41.2% males and 12.4% females till the end of the study. Adults accounted for most of the cases (94.3%) of COVID-19. Fever (86.60%), cough (85.05%), fatigue (36.60%), dyspnea (24.74%), and gastrointestinal discomfort (10.31%) were among the most frequently reported signs and symptoms by the patients. However, 4.12% of the total patient population remained asymptomatic. The median duration of hospital stay was found to be 14 (0-19) days. The earliest source of the spread of the virus may be linked to the foreigners traveling to Pakistan. Spread among men was more as compared to women. A few cases were found to be positive, due to the direct contact with pets or livestock. Hypertension (7.73%), diabetes (4.64%), cardiovascular conditions (2.58%) were the most common co-morbidities. The percentage mortality was 2.50% with the highest mortality among elders.