Displaying publications 61 - 80 of 359 in total

Abstract:
Sort:
  1. Kow CS, Ramachandram DS, Hasan SS
    Int Immunopharmacol, 2022 Feb;103:108455.
    PMID: 34959188 DOI: 10.1016/j.intimp.2021.108455
    Matched MeSH terms: Antiviral Agents/therapeutic use*
  2. Kow CS, Ramachandram DS, Hasan SS
    Immunopharmacol Immunotoxicol, 2022 Feb;44(1):28-34.
    PMID: 34762561 DOI: 10.1080/08923973.2021.1993894
    AIM: Several randomized trials have evaluated the effect of neutralizing monoclonal antibodies on the risk of hospital admission and risk of mortality in patients with COVID-19. We aimed to summarize the overall evidence in the form of a systematic review and meta-analysis.

    METHODS: A systematic literature search with no language restriction was performed in electronic databases and preprint repositories to identify eligible studies published up to 29 June 2021. The outcomes of interest were hospital admission and all-cause mortality. A random-effects model was used to estimate the pooled odds ratio (OR) for outcomes of interest with the use of neutralizing monoclonal antibodies relative to nonuse of neutralizing monoclonal antibodies, at 95% confidence intervals (CI).

    RESULTS: Our systematic literature search identified nine randomized controlled trials. Three trials had an overall low risk of bias, while four trials had some concerns in the overall risk of bias. The meta-analysis revealed no statistically significant difference in the odds of mortality (pooled OR = 0.69; 95% CI 0.33-1.47), but a statistically significant reduction in the odds of hospital admission (pooled OR = 0.29; 95% CI 0.21-0.42), with the administration of a neutralizing monoclonal antibody among patients with COVID-19, relative to non-administration of a neutralizing monoclonal antibody, at the current sample size.

    CONCLUSION: The reduced risk of hospital admission with neutralizing monoclonal antibodies use suggests that the timing of neutralizing antibodies administration is key in preventing hospital admission and, ultimately, death. Future randomized trials should aim to determine if the clinical outcomes with neutralizing monoclonal antibodies differ based on serostatus.

    Matched MeSH terms: Antiviral Agents/therapeutic use
  3. Khalifa SAM, Yosri N, El-Mallah MF, Ghonaim R, Guo Z, Musharraf SG, et al.
    Phytomedicine, 2021 May;85:153311.
    PMID: 33067112 DOI: 10.1016/j.phymed.2020.153311
    BACKGROUND: Starting December 2019, mankind faced an unprecedented enemy, the COVID-19 virus. The world convened in international efforts, experiences and technologies in order to fight the emerging pandemic. Isolation, hygiene measure, diagnosis, and treatment are the most efficient ways of prevention and intervention nowadays. The health organizations and global care systems screened the available resources and offered recommendations of approved and proposed medications. However, the search for a specific selective therapy or vaccine against COVID-19 remains a challenge.

    METHODS: A literature search was performed for the screening of natural and derived bio-active compounds which showed potent antiviral activity against coronaviruses using published articles, patents, clinical trials website (https://clinicaltrials.gov/) and web databases (PubMed, SCI Finder, Science Direct, and Google Scholar).

    RESULTS: Through the screening for natural products with antiviral activities against different types of the human coronavirus, extracts of Lycoris radiata (L'Hér.), Gentiana scabra Bunge, Dioscorea batatas Decne., Cassia tora L., Taxillus chinensis (DC.), Cibotium barometz L. and Echinacea purpurea L. showed a promising effect against SARS-CoV. Out of the listed compound Lycorine, emetine dihydrochloride hydrate, pristimerin, harmine, conessine, berbamine, 4`-hydroxychalcone, papaverine, mycophenolic acid, mycophenolate mofetil, monensin sodium, cycloheximide, oligomycin and valinomycin show potent activity against human coronaviruses. Additionally, it is worth noting that some compounds have already moved into clinical trials for their activity against COVID-19 including fingolimod, methylprednisolone, chloroquine, tetrandrine and tocilizumab.

    CONCLUSION: Natural compounds and their derivatives could be used for developing potent therapeutics with significant activity against SARS-COV-2, providing a promising frontline in the fighting against COVID-19.

    Matched MeSH terms: Antiviral Agents/pharmacology*
  4. Ahmad MA, Lim YH, Chan YS, Hsu CY, Wu TY, Sit NW
    Acta Pharm, 2022 Jun 01;72(2):317-328.
    PMID: 36651512 DOI: 10.2478/acph-2022-0013
    This study was conducted to evaluate the chemical composition and biological activities of the leaf extracts of Syzygium myrtifolium Walp. (Myrtaceae). The results indicate that the leaf extracts of S. myrtifolium contain various classes of phytochemicals (alkaloids, anthraquinones, flavonoids, phenolics, saponins, tannins and triterpenoids) and possess antioxidant, antibacterial, antifungal and antiviral activities. Ethyl acetate, ethanol, methanol, and water extracts exhibited significantly higher (p < 0.05) oxygen radical absorbance capacity and ferric-reducing antioxidant power than the hexane and chloroform extracts. However, all extracts exhibited stronger inhibitory activity against four tested species of yeasts (minimal inhibitory concentration: 0.02-0.31 mg mL-1) than against six tested species of bacteria (minimal inhibitory concentration: 0.16-1.25 mg mL-1). The ethanolic extract offered the highest protection of Vero cells (viability > 70 %) from the cytopathic effect caused by the Chikungunya virus while the ethyl acetate extract showed significant replication inhibitory activity against the virus (p < 0.001) using the replicon-enhanced green fluorescent protein reporter system.
    Matched MeSH terms: Antiviral Agents/pharmacology
  5. Azzeri A, Dahlui M, Mohamed R, McDonald SA, Jaafar H, Shabaruddin FH
    Front Public Health, 2023;11:1114560.
    PMID: 36935675 DOI: 10.3389/fpubh.2023.1114560
    INTRODUCTION: A scaled-up treatment cascade with direct-acting antiviral (DAA) therapy is necessary to achieve global WHO targets for hepatitis C virus (HCV) elimination in Malaysia. Recently, limited access to sofosbuvir/daclatasvir (SOF/DAC) is available through compulsory licensing, with access to sofosbuvir/velpatasvir (SOF/VEL) expected through voluntary licensing due to recent agreements. SOF/VEL has superior clinical outcomes but has higher drug acquisition costs compared to SOF/DAC. A stratified treatment cascade might be the most cost-efficient approach for Malaysia whereby all HCV patients are treated with SOF/DAC except for patients with cirrhosis who are treated with SOF/VEL.

    METHODS: This study aimed to conduct a 5-year budget impact analysis of the proposed stratified treatment cascade for HCV treatment in Malaysia. A disease progression model that was developed based on model-predicted HCV epidemiology data was used for the analysis, where all HCV patients in scenario A were treated with SOF/DAC for all disease stages while in scenario B, SOF/DAC was used only for non-cirrhotic patients and SOF/VEL was used for the cirrhotic patients. Healthcare costs associated with DAA therapy and disease stage monitoring were included to estimate the downstream cost implications.

    RESULTS: The stratified treatment cascade with 109 in Scenario B was found to be cost-saving compared to Scenario A. The cumulative savings for the stratified treatment cascade was USD 1.4 million over 5 years.

    DISCUSSION: A stratified treatment cascade with SOF/VEL was expected to be cost-saving and can result in a budget impact reduction in overall healthcare expenditure in Malaysia.

    Matched MeSH terms: Antiviral Agents/therapeutic use
  6. Faheem, Kumar BK, Sekhar KVGC, Kunjiappan S, Jamalis J, Balaña-Fouce R, et al.
    Bioorg Chem, 2020 Nov;104:104269.
    PMID: 32947136 DOI: 10.1016/j.bioorg.2020.104269
    COVID-19 caused by the novel SARS-CoV-2 has been declared a pandemic by the WHO is causing havoc across the entire world. As of May end, about 6 million people have been affected, and 367 166 have died from COVID-19. Recent studies suggest that the SARS-CoV-2 genome shares about 80% similarity with the SARS-CoV-1 while their protein RNA dependent RNA polymerase (RdRp) shares 96% sequence similarity. Remdesivir, an RdRp inhibitor, exhibited potent activity against SARS-CoV-2 in vitro. 3-Chymotrypsin like protease (also known as Mpro) and papain-like protease, have emerged as the potential therapeutic targets for drug discovery against coronaviruses owing to their crucial role in viral entry and host-cell invasion. Crystal structures of therapeutically important SARS-CoV-2 target proteins, namely, RdRp, Mpro, endoribonuclease Nsp15/NendoU and receptor binding domain of CoV-2 spike protein has been resolved, which have facilitated the structure-based design and discovery of new inhibitors. Furthermore, studies have indicated that the spike proteins of SARS-CoV-2 use the Angiotensin Converting Enzyme-2 (ACE-2) receptor for its attachment similar to SARS-CoV-1, which is followed by priming of spike protein by Transmembrane protease serine 2 (TMPRSS2) which can be targeted by a proven inhibitor of TMPRSS2, camostat. The current treatment strategy includes repurposing of existing drugs that were found to be effective against other RNA viruses like SARS, MERS, and Ebola. This review presents a critical analysis of druggable targets of SARS CoV-2, new drug discovery, development, and treatment opportunities for COVID-19.
    Matched MeSH terms: Antiviral Agents/therapeutic use*
  7. Hassan MRA, Chan HK, Nordin M, Yahya R, Sulaiman WRW, Merican SAA, et al.
    Harm Reduct J, 2023 Apr 12;20(1):48.
    PMID: 37046294 DOI: 10.1186/s12954-023-00780-3
    BACKGROUND: Despite advancements in hepatitis C virus (HCV) treatment, low uptake among hard-to-reach populations remains a global issue. The current study aimed to assess the feasibility of a modified same-day test-and-treat model in improving HCV care for people who inject drugs (PWID) living in resource-constrained rural areas.

    METHODS: A pilot study was conducted in four primary healthcare (PHC) centers in Malaysia. The model's key features included on-site HCV ribonucleic acid (RNA) testing using a shared GeneXpert® system; noninvasive biomarkers for cirrhosis diagnosis; and extended care to PWID referred from nearby PHC centers and outreach programs. The feasibility assessment focused on three aspects of the model: demand (i.e., uptake of HCV RNA testing and treatment), implementation (i.e., achievement of each step in the HCV care cascade), and practicality (i.e., ability to identify PWID with HCV and expedite treatment initiation despite resource constraints).

    RESULTS: A total of 199 anti-HCV-positive PWID were recruited. They demonstrated high demand for HCV care, with a 100% uptake of HCV RNA testing and 97.4% uptake of direct-acting antiviral treatment. The rates of HCV RNA positivity (78.4%) and sustained virologic response (92.2%) were comparable to standard practice, indicating the successful implementation of the model. The model was also practical, as it covered non-opioid-substitution-therapy-receiving individuals and enabled same-day treatment in 71.1% of the participants.

    CONCLUSIONS: The modified same-day test-and-treat model is feasible in improving HCV care for rural PWID. The study finding suggests its potential for wider adoption in HCV care for hard-to-reach populations.

    Matched MeSH terms: Antiviral Agents/therapeutic use
  8. Augustin Y, Staines HM, Velavan TP, Kamarulzaman A, Kremsner PG, Krishna S
    Br Med Bull, 2023 Sep 12;147(1):31-49.
    PMID: 37312588 DOI: 10.1093/bmb/ldac037
    INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic resulted in a race to develop effective treatments largely through drug repurposing via adaptive platform trials on a global scale. Drug repurposing trials have focused on potential antiviral therapies aimed at preventing viral replication, anti-inflammatory agents, antithrombotic agents and immune modulators through a number of adaptive platform trials. Living systematic reviews have also enabled evidence synthesis and network meta-analysis as clinical trial data emerge globally.

    SOURCES OF DATA: Recent published literature.

    AREAS OF AGREEMENT: Corticosteroids and immunomodulators that antagonize the interleukin-6 (IL-6) receptor have been shown to play a critical role in modulating inflammation and improving clinical outcomes in hospitalized patients. Inhaled budesonide reduces the time to recovery in older patients with mild-to-moderate COVID-19 managed in the community.

    AREAS OF CONTROVERSY: The clinical benefit of remdesivir remains controversial with conflicting evidence from different trials. Remdesivir led to a reduction in time to clinical recovery in the ACTT-1 trial. However, the World Health Organization SOLIDARITY and DISCOVERY trial did not find a significant benefit on 28-day mortality and clinical recovery.

    GROWING POINTS: Other treatments currently being investigated include antidiabetic drug empagliflozin, antimalarial drug artesunate, tyrosine kinase inhibitor imatinib, immunomodulatory drug infliximab, antiviral drug favipiravir, antiparasitic drug ivermectin and antidepressant drug fluvoxamine.

    AREAS TIMELY FOR DEVELOPING RESEARCH: The timing of therapeutic interventions based on postulated mechanisms of action and the selection of clinically meaningful primary end points remain important considerations in the design and implementation of COVID-19 therapeutic trials.

    Matched MeSH terms: Antiviral Agents/therapeutic use
  9. Hanna GS, Choo YM, Harbit R, Paeth H, Wilde S, Mackle J, et al.
    J Nat Prod, 2021 Nov 26;84(11):3001-3007.
    PMID: 34677966 DOI: 10.1021/acs.jnatprod.1c00625
    The pressing need for SARS-CoV-2 controls has led to a reassessment of strategies to identify and develop natural product inhibitors of zoonotic, highly virulent, and rapidly emerging viruses. This review article addresses how contemporary approaches involving computational chemistry, natural product (NP) and protein databases, and mass spectrometry (MS) derived target-ligand interaction analysis can be utilized to expedite the interrogation of NP structures while minimizing the time and expense of extraction, purification, and screening in BioSafety Laboratories (BSL)3 laboratories. The unparalleled structural diversity and complexity of NPs is an extraordinary resource for the discovery and development of broad-spectrum inhibitors of viral genera, including Betacoronavirus, which contains MERS, SARS, SARS-CoV-2, and the common cold. There are two key technological advances that have created unique opportunities for the identification of NP prototypes with greater efficiency: (1) the application of structural databases for NPs and target proteins and (2) the application of modern MS techniques to assess protein-ligand interactions directly from NP extracts. These approaches, developed over years, now allow for the identification and isolation of unique antiviral ligands without the immediate need for BSL3 facilities. Overall, the goal is to improve the success rate of NP-based screening by focusing resources on source materials with a higher likelihood of success, while simultaneously providing opportunities for the discovery of novel ligands to selectively target proteins involved in viral infection.
    Matched MeSH terms: Antiviral Agents/pharmacology*
  10. Lu AY, Gustin A, Newhouse D, Gale M
    J Virol, 2023 May 31;97(5):e0198222.
    PMID: 37162358 DOI: 10.1128/jvi.01982-22
    Asian lineage Zika virus (ZIKV) strains emerged globally, causing outbreaks linked with critical clinical disease outcomes unless the virus is effectively restricted by host immunity. We have previously shown that retinoic acid-inducible gene-I (RIG-I) senses ZIKV to trigger innate immunity to direct interferon (IFN) production and antiviral responses that can control ZIKV infection. However, ZIKV proteins have been demonstrated to antagonize IFN. Here, we conducted in vitro analyses to assess how divergent prototypic ZIKV variants differ in virologic properties, innate immune regulation, and infection outcome. We comparatively assessed African lineage ZIKV/Dakar/1984/ArD41519 (ZIKV/Dakar) and Asian lineage ZIKV/Malaysia/1966/P6740 (ZIKV/Malaysia) in a human epithelial cell infection model. De novo viral sequence determination identified amino acid changes within the ZIKV/Dakar genome compared to ZIKV/Malaysia. Viral growth analyses revealed that ZIKV/Malaysia accumulated viral proteins and genome copies earlier and to higher levels than ZIKV/Dakar. Both ZIKV strains activated RIG-I/IFN regulatory factor (IRF3) and NF-κB pathways to induce inflammatory cytokine expression and types I and III IFNs. However, ZIKV/Malaysia, but not ZIKV/Dakar, potently blocked downstream IFN signaling. Remarkably, ZIKV/Dakar protein accumulation and genome replication were rescued in RIG-I knockout (KO) cells late in acute infection, resulting in ZIKV/Dakar-mediated blockade of IFN signaling. We found that RIG-I signaling specifically restricts viral protein accumulation late in acute infection where early accumulation of viral proteins in infected cells confers enhanced ability to limit IFN signaling, promoting viral replication and spread. Our results demonstrate that RIG-I-mediated innate immune signaling imparts restriction of ZIKV protein accumulation, which permits IFN signaling and antiviral actions controlling ZIKV infection. IMPORTANCE ZIKV isolates are classified under African or Asian lineages. Infection with emerging Asian lineage-derived ZIKV strains is associated with increased incidence of neurological symptoms that were not previously reported during infection with African or preemergent Asian lineage viruses. In this study, we utilized in vitro models to compare the virologic properties of and innate immune responses to two prototypic ZIKV strains from distinct lineages: African lineage ZIKV/Dakar and Asian lineage ZIKV/Malaysia. Compared to ZIKV/Dakar, ZIKV/Malaysia accumulates viral proteins earlier, replicates to higher levels, and robustly blocks IFN signaling during acute infection. Early accumulation of ZIKV/Malaysia NS5 protein confers enhanced ability to antagonize IFN signaling, dampening innate immune responses to promote viral spread. Our data identify the kinetics of viral protein accumulation as a major regulator of host innate immunity, influencing host-mediated control of ZIKV replication and spread. Importantly, these findings provide a novel framework for evaluating the virulence of emerging variants.
    Matched MeSH terms: Antiviral Agents/pharmacology
  11. Kanauchi O, Low ZX, Jounai K, Tsuji R, AbuBakar S
    Front Immunol, 2023;14:1280680.
    PMID: 38116008 DOI: 10.3389/fimmu.2023.1280680
    The COVID-19 outbreak has caused significant global changes and increased public awareness of SARS-CoV-2. Substantial progress in developing vaccines, enhancing sanitation practices, and implementing various measures to combat the virus, including the utilization of probiotics has been made. This comprehensive review examined the medical impact of clinically proven probiotics on infectious diseases, considering three crucial time periods: before (pre-), during (mid-), and after (post-) COVID-19 pandemic era. This review also showed a perspective on the use of probiotics to stimulate the innate immune system and prevent infectious diseases. In pre-COVID-19 era, several probiotic strains were found to be clinically effective in addressing gastrointestinal infectious diseases, the common cold and flu. However, the mechanism by which probiotics exerted their antiviral effects remained relatively unclear during that period. Nevertheless, probiotics, Lactococcus lactis strain Plasma (LC-Plasma), and others have gained attention for their unique ability to modulate the immune system and demonstrate antiviral properties. While some probiotics have shown promise in alleviating gastrointestinal symptoms linked to COVID-19, their direct effectiveness in treating or preventing COVID-19 progression has not yet been conclusively established. As we transition into the post-COVID-19 era, the relationship between COVID-19 and plasmacytoid dendritic cells (pDCs), a vital component of the innate immune system, has been gradually elucidated. These findings are now being applied in developing novel vaccines and treatments involving interferons and in immune activation research using probiotics as adjuvants, comparable to CpG-DNA through TLR9. The role of the local innate immune system, including pDCs, as the first line of defense against viral infections has gained increasing interest. Moving forward, insight of the immune system and the crosstalk between probiotics and the innate immune system is expected to highlight the role of probiotics in adjunctive immunoregulatory therapy. In combination with drug treatments, probiotics may play a more substantial role in enhancing immune responses. The immunoregulatory approach using probiotics such as LC-Plasma, which can induce anti-infectious factors such as interferons, holds promise as a viable therapeutic and prophylactic option against viral infectious diseases due to their good safety profile and protective efficacy.
    Matched MeSH terms: Antiviral Agents/therapeutic use
  12. Zelenev A, Li J, Shea P, Hecht R, Altice FL
    Clin Infect Dis, 2021 Mar 01;72(5):755-763.
    PMID: 32060534 DOI: 10.1093/cid/ciaa142
    BACKGROUND: Hepatitis C virus (HCV) treatment as prevention (TasP) strategies can contribute to HCV microelimination, yet complimentary interventions such as opioid agonist therapies (OAT) with methadone or buprenorphine and syringe services programs (SSPs) may improve the prevention impact. This modeling study estimates the impact of scaling up the combination of OAT and SSPs with HCV TasP in a network of people who inject drugs (PWID) in the United States.

    METHODS: Using empirical data from Hartford, Connecticut, we deployed a stochastic block model to simulate an injection network of 1574 PWID. We used a susceptible-infected model for HCV and human immunodeficiency virus to evaluate the effectiveness of several HCV TasP strategies, including in combination with OAT and SSP scale-up, over 20 years.

    RESULTS: At the highest HCV prevalence (75%), when OAT coverage is increased from 10% to 40%, combined with HCV treatment of 10% per year and SSP scale up to 40%, the time to achieve microelimination is reduced from 18.4 to 11.6 years. At the current HCV prevalence (60%), HCV TasP strategies as low as 10% coverage per year may achieve HCV microelimination within 10 years, with minimal impact from additional OAT scale-up. Strategies based on mass initial HCV treatment (50 per 100 PWID the first year followed by 5 per 100 PWID thereafter) were most effective in settings with HCV prevalence of 60% or lower.

    CONCLUSIONS: Scale-up of HCV TasP is the most effective strategy for microelimination of HCV. OAT scale-up, however, scale-up may be synergistic toward achieving microelimination goals when HCV prevalence exceeds 60% and when HCV treatment coverage is 10 per 100 PWID per year or lower.

    Matched MeSH terms: Antiviral Agents/therapeutic use
  13. Jasamai M, Simons C, Balzarini J
    PMID: 20589572 DOI: 10.1080/15257771003781634
    Acyclic nucleosides have been of considerable interest since the approval of aciclovir by the FDA to be used as an antiviral agent in the 1990s. The acyclic moieties and the bases used in the experiment were either available commercially or synthesized using literature methods. Vorbruggen coupling method was utilized involving reaction of persilylated heterocyclic bases with the appropriate acyclic moiety in the presence of a Lewis acid catalyst. A series of novel 6-azapyrimidine acyclic oxosugar nucleosides was successfully synthesized with a promising yield (more than 50%). An efficient method of protection and deprotection was also investigated.
    Matched MeSH terms: Antiviral Agents/chemical synthesis*; Antiviral Agents/pharmacology*; Antiviral Agents/chemistry
  14. Muhamad A, Ho KL, Rahman MB, Tejo BA, Uhrín D, Tan WS
    Org Biomol Chem, 2015 Jul 28;13(28):7780-9.
    PMID: 26100394 DOI: 10.1039/c5ob00449g
    Hepatitis B virus (HBV) infection remains a health problem globally despite the availability of effective vaccines. In the assembly of the infectious virion, both the preS and S regions of the HBV large surface antigen (L-HBsAg) interact synergistically with the viral core antigen (HBcAg). Peptides preS and S based on the L-HBsAg were demonstrated as potential inhibitors to block the viral assembly. Therefore, the objectives of this study were to determine the solution structures of these peptides and study their interactions with HBcAg. The solution structures of these peptides were solved using (1)H, (13)C, and (15)N NMR spectroscopy. Peptide preS has several structured regions of β-turns at Ser7-Pro8-Pro9, Arg11-Thr12-Thr13 and Ser22-Thr23-Thr24 sequences whereas peptide S has only one structured region observed at Ser3-Asn4-His5. Both peptides contain bend-like structures surrounding the turn structures. Docking studies revealed that both peptides interacted with the immunodominant region of HBcAg located at the tip of the viral capsid spikes. Saturation Transfer Difference (STD) NMR experiments identified several aromatic residues in peptides preS and S that interact with HBcAg. This study provides insights into the contact regions of L-HBsAg and HBcAg at atomic resolution which can be used to design antiviral agents that inhibit HBV morphogenesis.
    Matched MeSH terms: Antiviral Agents/isolation & purification; Antiviral Agents/pharmacology; Antiviral Agents/chemistry*
  15. Deng JG, Hou XT, Zhang TJ, Bai G, Hao EW, Chu JJH, et al.
    Chin Herb Med, 2020 Jul;12(3):207-213.
    PMID: 32834811 DOI: 10.1016/j.chmed.2020.05.003
    Members of the China-ASEAN Joint Laboratory for International Cooperation in Traditional Medicine Research used the video conference platform to exchange and discuss the advantages of traditional medicine through the form of score exchange and report, and research and develop the amount and issues of the therapeutic COVID-19 products of concern. This paper mainly reviews the achievements of the implementation of the epidemic prevention and control plan, advances of scientific basic studies on SARS-CoV-2, analysis and screening of potential targets and pathways of antiviral compounds based on network pharmacology and development of antiviral food dual-use products. The authors believe that the declaration of the (10 + 3) special meeting of national leaders on epidemic prevention and control should raise the medical and pharmaceutical issues of common concern. It is the responsibility of our joint laboratory members to accelerate the development of traditional medicine research and industry. Also the authors believe that this exchange will certainly promote the development of the cause of cooperation.
    Matched MeSH terms: Antiviral Agents
  16. Rahman MT
    J Herb Med, 2020 Oct;23:100382.
    PMID: 32834942 DOI: 10.1016/j.hermed.2020.100382
    An effective vaccine to prevent the SARS-CoV-2 causing COVID-19 is yet to be approved. Further there is no drug that is specific to treat COVID-19. A number of antiviral drugs such as Ribavirin, Remdesivir, Lopinavir/ritonavir, Azithromycin and Doxycycline have been recommended or are being used to treat COVID-19 patients. In addition to these drugs, rationale and evidence have been presented to use chloroquine to treat COVID-19, arguably with certain precautions and criticism. In line with the proposed use of chloroquine, Nigella sativa (black seed) could be considered as a natural substitute that contains a number of bioactive components such as thymoquinone, dithymoquinone, thymohydroquinone, and nigellimine. Further benefits to use N. sativa could be augmented by Zn supplement. Notably, Zn has been proven to improve innate and adaptive immunity in the course of any infection, be it by pathogenic virus or bacteria. The effectiveness of the Zn salt supplement could also be enhanced with N. sativa as its major bioactive component might work as ionophore to allow Zn2+ to enter pneumocytes - the target cell for SARSCoV-2. Given those benefits, this review paper describes how N. sativa in combination with Zn could be useful as a complement to COVID-19 treatment.
    Matched MeSH terms: Antiviral Agents
  17. Kamal MA, Smith PF, Chaiyakunapruk N, Wu DBC, Pratoomsoot C, Lee KKC, et al.
    Br J Clin Pharmacol, 2017 07;83(7):1580-1594.
    PMID: 28176362 DOI: 10.1111/bcp.13229
    AIMS: A modular interdisciplinary platform was developed to investigate the economic impact of oseltamivir treatment by dosage regimen under simulated influenza pandemic scenarios.

    METHODS: The pharmacology module consisted of a pharmacokinetic distribution of oseltamivir carboxylate daily area under the concentration-time curve at steady state (simulated for 75 mg and 150 mg twice daily regimens for 5 days) and a pharmacodynamic distribution of viral shedding duration obtained from phase II influenza inoculation data. The epidemiological module comprised a susceptible, exposed, infected, recovered (SEIR) model to which drug effect on the basic reproductive number (R0 ), a measure of transmissibility, was linked by reduction of viral shedding duration. The number of infected patients per population of 100 000 susceptible individuals was simulated for a series of pandemic scenarios, varying oseltamivir dose, R0 (1.9 vs. 2.7), and drug uptake (25%, 50%, and 80%). The number of infected patients for each scenario was entered into the health economics module, a decision analytic model populated with branch probabilities, disease utility, costs of hospitalized patients developing complications, and case-fatality rates. Change in quality-adjusted life years was determined relative to base case.

    RESULTS: Oseltamivir 75 mg relative to no treatment reduced the median number of infected patients, increased change in quality-adjusted life years by deaths averted, and was cost-saving under all scenarios; 150 mg relative to 75 mg was not cost effective in low transmissibility scenarios but was cost saving in high transmissibility scenarios.

    CONCLUSION: This methodological study demonstrates proof of concept that the disciplines of pharmacology, disease epidemiology and health economics can be linked in a single quantitative framework.

    Matched MeSH terms: Antiviral Agents/economics; Antiviral Agents/pharmacology; Antiviral Agents/therapeutic use*
  18. Nur Suhana Mohamad Ripim, Nuraini Fazil, Saidatul Nadrah Kholid Ibrahim, Adibah Ahamad Bahtiar, Yip Chee Wai, Nazlina Ibrahim, et al.
    Sains Malaysiana, 2018;47:1725-1730.
    A study was conducted to investigate the antiviral activity of aqueous extracts from Orthosiphon stamineus (OS).
    Extraction was done using different parts of OS. The whole plant except root (WPOS), leaves (LOS) and flowers (FOS) of
    OS were extracted using aqueous extraction method. Cytotoxicity was assessed using 3-(4,5-dimethylthiazol-2,5-diphenyl
    tetrazolium bromide (MTT) assay. Plaque reduction assays were carried out to evaluate the antiviral activity of OS extract
    against herpes simplex virus type 1 (HSV-1). These include post-treatment, pre-treatment and virucidal assays. High
    antiviral activity was observed in post-treatment and virucidal assay with 100% reduction of HSV-1 plaque at 0.39 mg/
    mL in LOS, FOS and WPOS. In pre-treatment assay, 79%, 84% and 97% plaque reduction using the same concentration
    was observed in FOS, LOS and WPOS, respectively. In conclusion, this study showed that OS aqueous extract has promising
    potential to be explored as anti-HSV-1 agent regardless of the mode of treatment.
    Matched MeSH terms: Antiviral Agents
  19. Saoin S, Wisitponchai T, Intachai K, Chupradit K, Moonmuang S, Nangola S, et al.
    Asian Pac J Allergy Immunol, 2018 06;36(2):126-135.
    PMID: 28802032 DOI: 10.12932/AP-280217-0037
    BACKGROUND: AnkGAG1D4 is an artificial ankyrin repeat protein which recognizes the capsid protein (CA) of the human immunodeficiency virus type 1 (HIV-1) and exhibits the intracellular antiviral activity on the viral assembly process. Improving the binding affinity of AnkGAG1D4 would potentially enhance the AnkGAG1D4-mediated antiviral activity.

    OBJECTIVE: To augment the affinity of AnkGAG1D4 scaffold towards its CA target, through computational predictions and experimental designs.

    METHOD: Three dimensional structure of the binary complex formed by AnkGAG1D4 docked to the CA was used as a model for van der Waals (vdW) binding energy calculation. The results generated a simple guideline to select the amino acids for modifications. Following the predictions, modified AnkGAG1D4 proteins were produced and further evaluated for their CA-binding activity, using ELISA-modified method and bio-layer interferometry (BLI).

    RESULTS: Tyrosine at position 56 (Y56) in AnkGAG1D4 was experimentally identified as the most critical residue for CA binding. Rational substitutions of this residue diminished the binding affinity. However, vdW calculation preconized to substitute serine for tyrosine at position 45. Remarkably, the affinity for the viral CA was significantly enhanced in AnkGAG1D4-S45Y mutant, with no alteration of the target specificity.

    CONCLUSIONS: The S-to-Y mutation at position 45, based on the prediction of interacting amino acids and on vdW binding energy calculation, resulted in a significant enhancement of the affinity of AnkGAG1D4 ankyrin for its CA target. AnkGAG1D4-S45Y mutant represented the starting point for further construction of variants with even higher affinity towards the viral CA, and higher therapeutic potential in the future.

    Matched MeSH terms: Antiviral Agents/metabolism; Antiviral Agents/pharmacology*; Antiviral Agents/chemistry*
  20. Alamri RD, Elmeligy MA, Albalawi GA, Alquayr SM, Alsubhi SS, El-Ghaiesh SH
    Int Immunopharmacol, 2021 Apr;93:107398.
    PMID: 33571819 DOI: 10.1016/j.intimp.2021.107398
    Leflunomide (LF) represents the prototype member of dihydroorotate dehydrogenase (DHODH) enzyme inhibitors. DHODH is a mitochondrial inner membrane enzyme responsible for catalytic conversion of dihydroorotate into orotate, a rate-limiting step in the de novo synthesis of the pyrimidine nucleotides. LF produces cellular depletion of pyrimidine nucleotides required for cell growth and proliferation. Based on the affected cells the outcome can be attainable as immunosuppression, antiproliferative, and/or the recently gained attention of the antiviral potentials of LF and its new congeners. Also, protein tyrosine kinase inhibition is an additional mechanistic benefit of LF, which inhibits immunological events such as cellular expansion and immunoglobulin production with an enhanced release of immunosuppressant cytokines. LF is approved for the treatment of autoimmune arthritis of rheumatoid and psoriatic pathogenesis. Also, LF has been used off-label for the treatment of relapsing-remitting multiple sclerosis. However, LF antiviral activity is repurposed and under investigation with related compounds under a phase-I trial as a SARS CoV-2 antiviral in cases with COVID-19. Despite success in improving patients' mobility and reducing joint destruction, reported events of LF-induced liver injury necessitated regulatory precautions. LF should not be used in patients with hepatic impairment or in combination with drugs elaborating a burden on the liver without regular monitoring of liver enzymes and serum bilirubin as safety biomarkers. This study aims to review the pharmacological and safety profile of LF with a focus on the LF-induced hepatic injury from the perspective of pathophysiology and possible protective agents.
    Matched MeSH terms: Antiviral Agents/adverse effects; Antiviral Agents/pharmacology; Antiviral Agents/therapeutic use
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links