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de Oliveira FMG, Lyrio MVV, Filgueiras PR, de Castro EVR, Kuster RM. ESI(-)FT-ICR MS for the determination of best conditions for producing extract abundant in phenolic compounds from leaves of E. uniflora and FTIR-PCA as a sample screening method. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2024; 16:3701-3713. [PMID: 38805183 DOI: 10.1039/d3ay00773a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
E. uniflora leaves are a rich source of phenolic compounds with biological activities, including myricitrin. In this study, the chemical profile of nine extracts prepared with leaves collected in three regions (mountain, beach, and mangrove) and at three different times of the day (8 am, 1 pm, and 6 pm) was evaluated from spectra originating from ultra-high resolution mass spectrometry (Fourier transform ion cyclotron resonance, FT-ICR) coupled to electrospray ionisation (ESI). The best time of the day and location for collecting the leaves of E. uniflora used as raw materials for producing extracts and the best ethanol concentration for obtaining an extract more abundant in compounds of interest were verified. Several flavonoids and phenolic acids were detected in their deprotonated form in the regions from m/z 200 to 1200. Myricitrin ([C21H20O12-H]-, m/ztheo 463.08820), its chloride adduct ([C21H20O12+Cl]-, m/ztheo 499.06488), other myricitrin derivatives, and some tannins were the main compounds detected. Considering obtaining an extract rich in phenolic compounds, including myricitrin, the best place and time of the day to collect E. uniflora leaves is in the beach region at 1 pm. In contrast, the best ethanol concentration for extract production is 70 wt%. Therefore, extraction at 96 wt% ethanol is better for obtaining an extract more abundant in phenolic acids, although 70 wt% ethanol also extracted these compounds. FTIR-PCA models were used to check for possible similarities in the data according to collection time of the day and location. These models demonstrated an excellent solution for sample screening.
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Affiliation(s)
- Fernanda M G de Oliveira
- LABPETRO (Laboratory of Research and Methodologies Development for Petroleum Analysis), Chemistry Department, Federal University of Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, P. O. Box: 29075-910, Vitória, ES, Brazil.
| | - Marcos V V Lyrio
- LABPETRO (Laboratory of Research and Methodologies Development for Petroleum Analysis), Chemistry Department, Federal University of Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, P. O. Box: 29075-910, Vitória, ES, Brazil.
| | - Paulo R Filgueiras
- LABPETRO (Laboratory of Research and Methodologies Development for Petroleum Analysis), Chemistry Department, Federal University of Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, P. O. Box: 29075-910, Vitória, ES, Brazil.
| | - Eustáquio V R de Castro
- LABPETRO (Laboratory of Research and Methodologies Development for Petroleum Analysis), Chemistry Department, Federal University of Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, P. O. Box: 29075-910, Vitória, ES, Brazil.
| | - Ricardo M Kuster
- LABPETRO (Laboratory of Research and Methodologies Development for Petroleum Analysis), Chemistry Department, Federal University of Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, P. O. Box: 29075-910, Vitória, ES, Brazil.
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Yin Y, Li J, Su L, Ou Z, Lv Q, Xiao M, Wang C, Zeng D, Gu Y, Yang F, Chen M, Feng S, Hu W, Bu F, Zhu B, Xu Y. Screening and verification of antiviral compounds against HSV-1 using a method based on a plaque inhibition assay. BMC Infect Dis 2023; 23:890. [PMID: 38114935 PMCID: PMC10731695 DOI: 10.1186/s12879-023-08843-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/24/2023] [Indexed: 12/21/2023] Open
Abstract
BACKGROUND Herpes simplex virus type 1 (HSV-1) infection is a common viral disease that mainly causes oral lesions, but can also cause genital lesions in some instances. Current treatments with nucleoside analogs are limited by the emergence of drug resistance. Therefore, novel anti-HSV-1 drugs are urgently needed. METHODS In this study, we screened a library of 2080 compounds for anti-HSV-1 activity using a plaque formation assay. We selected 11 potential inhibitors of HSV-1 and further evaluated their antiviral effects by plaque reduction assay and real-time polymerase chain reaction (qPCR). RESULTS Five compounds, namely ginsenoside Rd, brassinolide, rosamultin, 3'-hydroxy puerarin, and clinafloxacin HCl, showed potent anti-HSV-1 activity and completely suppressed plaque formation at a concentration of 10 µM. Among them, clinafloxacin HCl, a fluoroquinolone antibiotic, exhibited a high selectivity index for HSV-1. CONCLUSIONS Our findings suggest that these five compounds have potential antiviral properties against HSV-1 and may have different mechanisms of action. Further studies are warranted to elucidate the antiviral mechanisms of these compounds and to explore their therapeutic potential for HSV-1 infection.
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Affiliation(s)
- Yingxian Yin
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Jiahui Li
- Department of Infectious Diseases, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Ling Su
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Zhiying Ou
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Qingqun Lv
- School of Pediatrics, Guangzhou Medical University, Guangzhou, 510623, China
| | - Misi Xiao
- Central Laboratory, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Changbing Wang
- Central Laboratory, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Dan Zeng
- Department of Infectious Diseases, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Yiling Gu
- Department of Infectious Diseases, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Fengxia Yang
- Department of Infectious Diseases, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Minxia Chen
- Department of Infectious Diseases, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Shaojuan Feng
- Department of Oral and Maxillofacial Surgery, Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Wanming Hu
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Operating room, Guangzhou, 510120, China
| | - Fengling Bu
- Department of Disease Control and Prevention, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Bing Zhu
- Central Laboratory, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China
| | - Yi Xu
- Department of Infectious Diseases, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510120, China.
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Le TTV, Do PC. Molecular docking study of various Enterovirus—A71 3C protease proteins and their potential inhibitors. Front Microbiol 2022; 13:987801. [PMID: 36246267 PMCID: PMC9563145 DOI: 10.3389/fmicb.2022.987801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/23/2022] [Indexed: 12/04/2022] Open
Abstract
Hand, foot, and mouth disease (HFMD) is a common infection that primarily affects children in preschool and kindergarten; however, there is yet no vaccination or therapy available. Despite the fact that current research is only focused on numerous strains of Enterovirus—A71 (EV-A71) 3C protease (3Cpro), these investigations are entirely separate and unrelated. Antiviral agents must therefore be tested on several EV strains or mutations. In total, 21 previously reported inhibitors were evaluated for inhibitory effects on eight EV-A71 3Cpro, including wild-type and mutant proteins in this study, and another 29 powerful candidates with inhibitory effects on EV-A71 were investigated using the molecular docking approach. This method is to determine the broad-spectrum of the antiviral agents on a range of strains or mutants because the virus frequently has mutations. Even though Rupintrivir is reported to pass phase I clinical trial, 4-iminooxazolidin-2-one moiety (FIOMC) was shown to have a broader anti-3Cpro spectrum than Rupintrivir. Meanwhile, Hesperidin possessed a better 3Cpro inhibitory capability than FIOMC. Thus, it could be considered the most promising candidate for inhibiting various strains of EV-A71 3Cpro proteins in the newly anti-EV compounds group. Furthermore, the mutation at E71A has the most significant impact on the docking results of all ligands evaluated. Future in vitro experiments on Hesperidin’s ability to inhibit 3Cpro activity should be conducted to compare with FIOMC’s in vitro results and validate the current in silico work.
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Affiliation(s)
- Tran Thao Vy Le
- School of Biotechnology, International University, Ho Chi Minh City, Vietnam
- Vietnam National University, Ho Chi Minh City, Vietnam
| | - Phuc-Chau Do
- School of Biotechnology, International University, Ho Chi Minh City, Vietnam
- Vietnam National University, Ho Chi Minh City, Vietnam
- *Correspondence: Phuc-Chau Do,
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Phanomchoeng G, Kukiattikoon C, Plengkham S, Boonyasuppayakorn S, Salakij S, Poomrittigul S, Wuttisittikulkij L. Machine-learning-based automated quantification machine for virus plaque assay counting. PeerJ Comput Sci 2022; 8:e878. [PMID: 35494866 PMCID: PMC9044226 DOI: 10.7717/peerj-cs.878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
The plaque assay is a standard quantification system in virology for verifying infectious particles. One of the complex steps of plaque assay is the counting of the number of viral plaques in multiwell plates to study and evaluate viruses. Manual counting plaques are time-consuming and subjective. There is a need to reduce the workload in plaque counting and for a machine to read virus plaque assay; thus, herein, we developed a machine-learning (ML)-based automated quantification machine for viral plaque counting. The machine consists of two major systems: hardware for image acquisition and ML-based software for image viral plaque counting. The hardware is relatively simple to set up, affordable, portable, and automatically acquires a single image or multiple images from a multiwell plate for users. For a 96-well plate, the machine could capture and display all images in less than 1 min. The software is implemented by K-mean clustering using ML and unsupervised learning algorithms to help users and reduce the number of setup parameters for counting and is evaluated using 96-well plates of dengue virus. Bland-Altman analysis indicates that more than 95% of the measurement error is in the upper and lower boundaries [±2 standard deviation]. Also, gage repeatability and reproducibility analysis showed that the machine is capable of applications. Moreover, the average correct measurements by the machine are 85.8%. The ML-based automated quantification machine effectively quantifies the number of viral plaques.
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Affiliation(s)
- Gridsada Phanomchoeng
- Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
- Applied Medical Virology Research Unit, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
| | - Chayatorn Kukiattikoon
- Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
| | - Suphanut Plengkham
- Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
| | - Siwaporn Boonyasuppayakorn
- Applied Medical Virology Research Unit, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
- Department of Microbiology, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
| | - Saran Salakij
- Department of Mechanical Engineering, Faculty of Engineering, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
- Applied Medical Virology Research Unit, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
| | - Suvit Poomrittigul
- Department of Software Engineering and Information System, Pathumwan Institute of Technology, Pathumwan Institute of Technology, Bangkok, Thailand
| | - Lunchakorn Wuttisittikulkij
- Department of Electrical Engineering, Faculty of Engineering, Chulalongkorn University, Chulalongkorn University, Bangkok, Thailand
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Nanotechnology Applications of Flavonoids for Viral Diseases. Pharmaceutics 2021; 13:pharmaceutics13111895. [PMID: 34834309 PMCID: PMC8625292 DOI: 10.3390/pharmaceutics13111895] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/14/2021] [Accepted: 11/01/2021] [Indexed: 12/14/2022] Open
Abstract
Recent years have witnessed the emergence of several viral diseases, including various zoonotic diseases such as the current pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Other viruses, which possess pandemic-causing potential include avian flu, Ebola, dengue, Zika, and Nipah virus, as well as the re-emergence of SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome) coronaviruses. Notably, effective drugs or vaccines against these viruses are still to be discovered. All the newly approved vaccines against the SARS-CoV-2-induced disease COVID-19 possess real-time possibility of becoming obsolete because of the development of ‘variants of concern’. Flavonoids are being increasingly recognized as prophylactic and therapeutic agents against emerging and old viral diseases. Around 10,000 natural flavonoid compounds have been identified, being phytochemicals, all plant-based. Flavonoids have been reported to have lesser side effects than conventional anti-viral agents and are effective against more viral diseases than currently used anti-virals. Despite their abundance in plants, which are a part of human diet, flavonoids have the problem of low bioavailability. Various attempts are in progress to increase the bioavailability of flavonoids, one of the promising fields being nanotechnology. This review is a narrative of some anti-viral dietary flavonoids, their bioavailability, and various means with an emphasis on the nanotechnology system(s) being experimented with to deliver anti-viral flavonoids, whose systems show potential in the efficient delivery of flavonoids, resulting in increased bioavailability.
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Barboza CM, Pimenta DC, Vigerelli H, de Cássia Rodrigues da Silva A, Garcia JG, Zamudio RM, Castilho JG, Montanha JA, Roehe PM, de Carvalho Ruthner Batista HB. In vitro effects of bufotenine against RNA and DNA viruses. Braz J Microbiol 2021; 52:2475-2482. [PMID: 34562234 PMCID: PMC8475449 DOI: 10.1007/s42770-021-00612-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 09/19/2021] [Indexed: 12/16/2022] Open
Abstract
Bufotenine, an alkaloid that can be found in plant extracts and skin secretions of amphibians, is reported to have potential antiviral activity. The present study evaluated the antiviral activity of bufotenine against different genetic lineages of rabies virus (RABV, a single-stranded, negative-sense RNA virus), canine coronavirus (CCoV, a positive-sense RNA virus) and two double-stranded DNA viruses (two strains of herpes simplex virus type 1/HSV-1 [KOS and the acyclovir-resistant HSV-1 strain 29R] and canine adenovirus 2, CAV-2). The maximal non-toxic bufotenine concentrations in Vero and BHK-21 cells were determined by MTT assays. The antiviral activity of bufotenine against each virus was assessed by examination of reductions in infectious virus titres and plaque assays. All experiments were performed with and without bufotenine, and the results were compared. Bufotenine demonstrated significant RABV inhibitory activity. No antiviral action was observed against CCoV, CAV-2 or HSV-1. These findings indicate that the antiviral activity of bufotenine is somewhat linked to the particular infectious dose used and the genetic lineage of the virus, although the mechanisms of its effects remain undetermined.
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Affiliation(s)
- Camila Mosca Barboza
- Instituto Pasteur, Av. Paulista, São Paulo, 393, Brazil.
- Universidade Federal Do ABC, Santo André, Brazil.
| | | | - Hugo Vigerelli
- Laboratório de Genética, Instituto Butantan, São Paulo, SP, Brazil
| | | | - Jaíne Gonçalves Garcia
- Instituto Pasteur, Av. Paulista, São Paulo, 393, Brazil
- Universidade Federal Do ABC, Santo André, Brazil
| | - Raphaela Mello Zamudio
- Instituto Pasteur, Av. Paulista, São Paulo, 393, Brazil
- Universidade Federal Do ABC, Santo André, Brazil
| | | | - Jarbas Alves Montanha
- Departamento de Produção E Matéria-Prima - Faculdade de Farmácia da Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Paulo Michel Roehe
- Instituto de Ciências Básicas da Saúde/Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
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Chen S, Lu H, Liu Z, Yuan W. Comment on "Central Nervous System Involvement by Severe Acute Respiratory Syndrome Coronavirus -2 (SARS-CoV-2)". J Med Virol 2020; 92:1399-1400. [PMID: 32383264 PMCID: PMC7267376 DOI: 10.1002/jmv.25991] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/04/2020] [Accepted: 05/05/2020] [Indexed: 01/11/2023]
Affiliation(s)
- Siyang Chen
- Department of Molecular Microbiology and ImmunologyKeck School of Medicine, University of Southern CaliforniaLos AngelesCalifornia
| | - Hongjia Lu
- Department of Molecular Microbiology and ImmunologyKeck School of Medicine, University of Southern CaliforniaLos AngelesCalifornia
| | - Zhewei Liu
- Department of Molecular Microbiology and ImmunologyKeck School of Medicine, University of Southern CaliforniaLos AngelesCalifornia
| | - Weiming Yuan
- Department of Molecular Microbiology and ImmunologyKeck School of Medicine, University of Southern CaliforniaLos AngelesCalifornia
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From Ocean to Medicine: Pharmaceutical Applications of Metabolites from Marine Bacteria. Antibiotics (Basel) 2020; 9:antibiotics9080455. [PMID: 32731464 PMCID: PMC7460513 DOI: 10.3390/antibiotics9080455] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/17/2020] [Accepted: 07/25/2020] [Indexed: 12/21/2022] Open
Abstract
Oceans cover seventy percent of the planet's surface and besides being an immense reservoir of biological life, they serve as vital sources for human sustenance, tourism, transport and commerce. Yet, it is estimated by the National Oceanic and Atmospheric Administration (NOAA) that eighty percent of the oceans remain unexplored. The untapped biological resources present in oceans may be fundamental in solving several of the world's public health crises of the 21st century, which span from the rise of antibiotic resistance in bacteria, pathogenic fungi and parasites, to the rise of cancer incidence and viral infection outbreaks. In this review, health risks as well as how marine bacterial derived natural products may be tools to fight them will be discussed. Moreover, an overview will be made of the research pipeline of novel molecules, from identification of bioactive bacterial crude extracts to the isolation and chemical characterization of the molecules within the framework of the One Health approach. This review highlights information that has been published since 2014, showing the current relevance of marine bacteria for the discovery of novel natural products.
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Flavonoids as Antiviral Agents for Enterovirus A71 ( EV-A71). Viruses 2020; 12:v12020184. [PMID: 32041232 PMCID: PMC7077323 DOI: 10.3390/v12020184] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/21/2020] [Accepted: 01/22/2020] [Indexed: 12/15/2022] Open
Abstract
Flavonoids are natural biomolecules that are known to be effective antivirals. These biomolecules can act at different stages of viral infection, particularly at the molecular level to inhibit viral growth. Enterovirus A71 (EV-A71), a non-enveloped RNA virus, is one of the causative agents of hand, foot and mouth disease (HFMD), which is prevalent in Asia. Despite much effort, no clinically approved antiviral treatment is available for children suffering from HFMD. Flavonoids from plants serve as a vast reservoir of therapeutically active constituents that have been explored as potential antiviral candidates against RNA and DNA viruses. Here, we reviewed flavonoids as evidence-based natural sources of antivirals against non-picornaviruses and picornaviruses. The detailed molecular mechanisms involved in the inhibition of EV-A71 infections are discussed.
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Lim ZQ, Ng QY, Ng JWQ, Mahendran V, Alonso S. Recent progress and challenges in drug development to fight hand, foot and mouth disease. Expert Opin Drug Discov 2019; 15:359-371. [DOI: 10.1080/17460441.2019.1659241] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ze Qin Lim
- Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, Immunology program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Qing Yong Ng
- Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, Immunology program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Justin Wei Qing Ng
- Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, Immunology program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Vikneswari Mahendran
- Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, Immunology program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Sylvie Alonso
- Department of Microbiology&Immunology, Yong Loo Lin School of Medicine, Immunology program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
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