1
|
Che Hamzah AM, Chew CH, Al-Trad EI, Puah SM, Chua KH, A Rahman NI, Ismail S, Maeda T, Palittapongarnpim P, Yeo CC. Whole genome sequencing of methicillin-resistant Staphylococcus aureus clinical isolates from Terengganu, Malaysia, indicates the predominance of the EMRSA-15 (ST22-SCCmec IV) clone. Sci Rep 2024; 14:3485. [PMID: 38347106 PMCID: PMC10861583 DOI: 10.1038/s41598-024-54182-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 02/09/2024] [Indexed: 02/15/2024] Open
Abstract
Despite the importance of methicillin-resistant Staphylococcus aureus (MRSA) as a priority nosocomial pathogen, the genome sequences of Malaysian MRSA isolates are currently limited to a small pool of samples. Here, we present the genome sequence analyses of 88 clinical MRSA isolates obtained from the main tertiary hospital in Terengganu, Malaysia in 2016-2020, to obtain in-depth insights into their characteristics. The EMRSA-15 (ST22-SCCmec IV) clone of the clonal complex 22 (CC22) lineage was predominant with a total of 61 (69.3%) isolates. Earlier reports from other Malaysian hospitals indicated the predominance of the ST239 clone, but only two (2.3%) isolates were identified in this study. Two Indian-origin clones, the Bengal Bay clone ST772-SCCmec V (n = 2) and ST672 (n = 10) were also detected, with most of the ST672 isolates obtained in 2020 (n = 7). Two new STs were found, with one isolate each, and were designated ST7879 and ST7883. From the core genome phylogenetic tree, the HSNZ MRSA isolates could be grouped into seven clades. Antimicrobial phenotype-genotype concordance was high (> 95%), indicating the accuracy of WGS in predicting most resistances. Majority of the MRSA isolates were found to harbor more than 10 virulence genes, demonstrating their pathogenic nature.
Collapse
Affiliation(s)
- Ainal Mardziah Che Hamzah
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300, Kuala Nerus, Terengganu, Malaysia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300, Kuala Nerus, Terengganu, Malaysia.
| | - Esra'a Ibrahim Al-Trad
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, 20400, Kuala Terengganu, Terengganu, Malaysia
- Faculty of Allied Medical Sciences, Jadara University, Irbid, Jordan
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Nor Iza A Rahman
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Salwani Ismail
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Toshinari Maeda
- Department of Biological Functions and Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-Ku, Kitakyushu, 808-0196, Japan
| | - Prasit Palittapongarnpim
- Pornchai Matangkasombut Center for Microbial Genomics (CENMIG), Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, 20400, Kuala Terengganu, Terengganu, Malaysia.
| |
Collapse
|
2
|
Jones SU, Chew CH, Yeo CC, Abdullah FH, Othman N, Kee BP, Chua KH, Puah SM. The phenotypes and genotypes associated with biofilm formation among methicillin-susceptible Staphylococcus aureus (MSSA) isolates collected from a tertiary hospital in Terengganu, Malaysia. Int Microbiol 2023; 26:841-849. [PMID: 36805382 DOI: 10.1007/s10123-023-00335-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 01/30/2023] [Accepted: 02/07/2023] [Indexed: 02/23/2023]
Abstract
Methicillin-susceptible Staphylococcus aureus (MSSA) is an important nosocomial pathogen worldwide. This study aims to investigate the in vitro biofilm-forming ability of clinical MSSA isolated from various sources in the main public tertiary referral hospital in Terengganu, Malaysia and to detect the presence of biofilm-associated and regulatory genes among these isolates. A total of 104 MSSA isolates [pus (n = 75), blood (n = 24), respiratory secretions (n = 2), eye (n = 2), and urine (n = 1)] were investigated for slime production and biofilm formation using Congo red agar and crystal violet microtitre plate, respectively. Fifteen MSSA isolates with varying degrees of biofilm formation were selected for validation via a real-time cell analyser. All isolates were screened for microbial surface components recognising adhesive matrix molecules (MSCRAMM) and accessory gene regulator (agr) using polymerase chain reaction assay. A total of 76.0% (79/104) isolates produced slime layer, while all isolates developed biofilm as follows: 52.8% (55/104) strong biofilm producers, 40.4% (42/104) intermediate biofilm producers, and 6.7% (7/104) weak biofilm producers. A total of 98.1% (102/104) isolates carried at least one of the screened MSCRAMM gene(s) with the eno gene detected at the highest rate (87.5%, 91/104), while the sasG gene was significantly associated with strong biofilm production (p = 0.015). Three agr groups, 1, 2, and 3, were detected among the MSSA isolates with a predominance of agr-3 (32.7%, 34/104). In conclusion, biofilm formation varied greatly among clinical MSSA isolates, and the presence of sasG gene and agr-1 may play important role in initiating MSSA infections via biofilm formation.
Collapse
Affiliation(s)
- Sherry Usun Jones
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300, Kuala Nerus, Terengganu, Malaysia
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Fatimah Haslina Abdullah
- Department of Pathology, Hospital Sultanah Nur Zahirah, 20400, Kuala Terengganu , Terengganu, Malaysia
| | - Norlela Othman
- Department of Pathology, Hospital Sultanah Nur Zahirah, 20400, Kuala Terengganu , Terengganu, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia.
| |
Collapse
|
3
|
Ng HK, Puah SM, Teh CSJ, Idris N, Chua KH. Comparative Transcriptomic Profiling of Pellicle and Planktonic Cells from Carbapenem-Resistant Acinetobacter baumannii. Antibiotics (Basel) 2023; 12:1185. [PMID: 37508281 PMCID: PMC10375965 DOI: 10.3390/antibiotics12071185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 06/24/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
Acinetobacter baumannii forms air-liquid interface pellicles that boost its ability to withstand desiccation and increase survival under antibiotic pressure. This study aims to delve into the transcriptomic profiles of pellicle cells from clinical strains of carbapenem-resistant A. baumannii (CRAB). The total RNA was extracted from pellicle cells from three pellicle-forming CRAB strains and planktonic cells from three non-pellicle-forming CRAB strains, subject to RNA sequencing using Illumina HiSeq 2500 system. A transcriptomic analysis between pellicle and planktonic cells, along with differential expression genes (DEGs) analysis and enrichment analysis of annotated COGs, GOs, and KEGGs, was performed. Our analysis identified 366 DEGs in pellicle cells: 162 upregulated genes and 204 downregulated genes. The upregulated ABUW_1624 (yiaY) gene and downregulated ABUW_1550 gene indicated potential involvement in fatty acid degradation during pellicle formation. Another upregulated ABUW_2820 (metQ) gene, encoding the D-methionine transporter system, hinted at its contribution to pellicle formation. The upregulation of two-component systems, CusSR and KdpDE, which implies the regulation of copper and potassium ions in a CRAB pellicle formation was also observed. These findings provide valuable insights into the regulation of gene expression during the formation of pellicles in CRAB, and these are potential targets that may aid in the eradication of CRAB infections.
Collapse
Affiliation(s)
- Heng Kang Ng
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Nuryana Idris
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| |
Collapse
|
4
|
Ng HK, Puah SM, Teh CSJ, Idris N, Chua KH. Characterisation of pellicle-forming ability in clinical carbapenem-resistant Acinetobacter baumannii. PeerJ 2023; 11:e15304. [PMID: 37214089 PMCID: PMC10194081 DOI: 10.7717/peerj.15304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 04/06/2023] [Indexed: 05/24/2023] Open
Abstract
Background Acinetobacter baumannii was reported to have resistance towards carbapenems and the ability to form an air-liquid biofilm (pellicle) which contributes to their virulence. The GacSA two-component system has been previously shown to play a role in pellicle formation. Therefore, this study aims to detect the presence of gacA and gacS genes in carbapenem-resistant Acinetobacter baumannii (CRAB) isolates recovered from patients in intensive care units and to investigate their pellicle forming ability. Methods The gacS and gacA genes were screened in 96 clinical CRAB isolates using PCR assay. Pellicle formation assay was performed in Mueller Hinton medium and Luria Bertani medium using borosilicate glass tubes and polypropylene plastic tubes. The biomass of the pellicle was quantitated using the crystal violet staining assay. The selected isolates were further assessed for their motility using semi-solid agar and monitored in real-time using real-time cell analyser (RTCA). Results All 96 clinical CRAB isolates carried the gacS and gacA genes, however, only four isolates (AB21, AB34, AB69 and AB97) displayed the ability of pellicle-formation phenotypically. These four pellicle-forming isolates produced robust pellicles in Mueller Hinton medium with better performance in borosilicate glass tubes in which biomass with OD570 ranging from 1.984 ± 0.383 to 2.272 ± 0.376 was recorded. The decrease in cell index starting from 13 hours obtained from the impedance-based RTCA showed that pellicle-forming isolates had entered the growth stage of pellicle development. Conclusion These four pellicle-forming clinical CRAB isolates could be potentially more virulent, therefore further investigation is warranted to provide insights into their pathogenic mechanisms.
Collapse
Affiliation(s)
- Heng Kang Ng
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Nuryana Idris
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
5
|
Al-Trad EI, Chew CH, Che Hamzah AM, Suhaili Z, Rahman NIA, Ismail S, Puah SM, Chua KH, Kwong SM, Yeo CC. The Plasmidomic Landscape of Clinical Methicillin-Resistant Staphylococcus aureus Isolates from Malaysia. Antibiotics (Basel) 2023; 12:antibiotics12040733. [PMID: 37107095 PMCID: PMC10135026 DOI: 10.3390/antibiotics12040733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 03/31/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a priority nosocomial pathogen with plasmids playing a crucial role in its genetic adaptability, particularly in the acquisition and spread of antimicrobial resistance. In this study, the genome sequences of 79 MSRA clinical isolates from Terengganu, Malaysia, (obtained between 2016 and 2020) along with an additional 15 Malaysian MRSA genomes from GenBank were analyzed for their plasmid content. The majority (90%, 85/94) of the Malaysian MRSA isolates harbored 1-4 plasmids each. In total, 189 plasmid sequences were identified ranging in size from 2.3 kb to ca. 58 kb, spanning all seven distinctive plasmid replication initiator (replicase) types. Resistance genes (either to antimicrobials, heavy metals, and/or biocides) were found in 74% (140/189) of these plasmids. Small plasmids (<5 kb) were predominant (63.5%, 120/189) with a RepL replicase plasmid harboring the ermC gene that confers resistance to macrolides, lincosamides, and streptogramin B (MLSB) identified in 63 MRSA isolates. A low carriage of conjugative plasmids was observed (n = 2), but the majority (64.5%, 122/189) of the non-conjugative plasmids have mobilizable potential. The results obtained enabled us to gain a rare view of the plasmidomic landscape of Malaysian MRSA isolates and reinforces their importance in the evolution of this pathogen.
Collapse
Affiliation(s)
- Esra'a I Al-Trad
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus 21300, Malaysia
| | | | - Zarizal Suhaili
- Faculty of Bioresources and Food Industry, Universiti Sultan Zainal Abidin, Besut 22200, Malaysia
| | - Nor Iza A Rahman
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
| | - Salwani Ismail
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Stephen M Kwong
- Infectious Diseases & Microbiology, School of Medicine, Western Sydney University, Campbelltown 2560, Australia
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
| |
Collapse
|
6
|
Al-Trad EI, Che Hamzah AM, Puah SM, Chua KH, Hanifah MZ, Ayub Q, Palittapongarnpim P, Kwong SM, Chew CH, Yeo CC. Complete Genome Sequence and Analysis of a ST573 Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus SauR3 Clinical Isolate from Terengganu, Malaysia. Pathogens 2023; 12:pathogens12030502. [PMID: 36986424 PMCID: PMC10053073 DOI: 10.3390/pathogens12030502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 03/17/2023] [Accepted: 03/21/2023] [Indexed: 03/30/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a World Health Organization-listed priority pathogen. Scarce genomic data are available for MRSA isolates from Malaysia. Here, we present the complete genome sequence of a multidrug-resistant MRSA strain SauR3, isolated from the blood of a 6-year-old patient hospitalized in Terengganu, Malaysia, in 2016. S. aureus SauR3 was resistant to five antimicrobial classes comprising nine antibiotics. The genome was sequenced on the Illumina and Oxford Nanopore platforms and hybrid assembly was performed to obtain its complete genome sequence. The SauR3 genome consists of a circular chromosome of 2,800,017 bp and three plasmids designated pSauR3-1 (42,928 bp), pSauR3-2 (3011 bp), and pSauR3-3 (2473 bp). SauR3 belongs to sequence type 573 (ST573), a rarely reported sequence type of the staphylococcal clonal complex 1 (CC1) lineage, and harbors a variant of the staphylococcal cassette chromosome mec (SCCmec) type V (5C2&5) element which also contains the aac(6')-aph(2″) aminoglycoside-resistance genes. pSauR3-1 harbors several antibiotic resistance genes in a 14,095 bp genomic island (GI), previously reported in the chromosome of other staphylococci. pSauR3-2 is cryptic, whereas pSauR3-3 encodes the ermC gene that mediates inducible resistance to macrolide-lincosamide-streptogramin B (iMLSB). The SauR3 genome can potentially be used as a reference genome for other ST573 isolates.
Collapse
Affiliation(s)
- Esra'a I Al-Trad
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
| | | | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Muhamad Zarul Hanifah
- Monash University Malaysia Genomics Facility, School of Science, Monash University, Bandar Sunway 47500, Malaysia
| | - Qasim Ayub
- Monash University Malaysia Genomics Facility, School of Science, Monash University, Bandar Sunway 47500, Malaysia
| | - Prasit Palittapongarnpim
- Pornchai Matangkasombut Center for Microbial Genomics (CENMIG), Mahidol University, Bangkok 10400, Thailand
| | - Stephen M Kwong
- Infectious Diseases & Microbiology, School of Medicine, Western Sydney University, Campbelltown 2560, Australia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus 21300, Malaysia
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
| |
Collapse
|
7
|
Nallappan D, Ong KC, Palanisamy UD, Chua KH, Kuppusamy UR. Myricetin derivative-rich fraction from Syzygium malaccense prevents high-fat diet-induced obesity, glucose intolerance and oxidative stress in C57BL/6J mice. Arch Physiol Biochem 2023; 129:186-197. [PMID: 32813560 DOI: 10.1080/13813455.2020.1808019] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
AIM A high-fat diet (HFD) can lead to obesity and related metabolic disorders. This study evaluated the preventive efficacy of myricetin derivative-rich fraction (MD) from Syzygium malaccense leaf extract against HFD-induced obesity, hyperglycaemia, and oxidative stress in C57BL/6J mice. METHODS HFD-fed mice were administered MD (50 mg/kg, 100 mg/kg, and 150 mg/kg) or 2 mg/kg metformin (positive control) orally for 16 weeks. Normal diet and HFD-fed control groups received normal saline. RESULTS MD dose of 50 mg/kg was better than 100 mg/kg and 150 mg/kg in significantly reducing weight-gain, glucose intolerance, insulin resistance, lipid accumulation in liver and kidney, and improving the serum lipid profile. Lowered protein carbonyls and lipid hydroperoxides in urine and tissue homogenates and elevated reduced glutathione, ferric reducing antioxidant power (FRAP), and Trolox equivalent antioxidant capacity (TEAC) levels in tissue homogenates indicated amelioration of oxidative stress. CONCLUSION MD has therapeutic value in the prevention and management of obesity, hyperglycaemia, and oxidative stress.
Collapse
Affiliation(s)
- Devi Nallappan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kien Chai Ong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Uma Devi Palanisamy
- Jeffrey Cheah School of Medicine and Health Science, Monash University, Bandar Sunway, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Umah Rani Kuppusamy
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
8
|
Tan EW, Chua KH, Jones SU, Tan LK, Loch A, Kee BP. Genetic investigation of point mutations in sarcomeric genes in Malaysian patients with cardiomyopathy. ScienceAsia 2023; 49:240. [DOI: 10.2306/scienceasia1513-1874.2023.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
|
9
|
Subramaniam S, Ong KC, Sabaratnam V, Chua KH, Kuppusamy UR. The medicinal mushroom Ganoderma neo-japonicum (Imazeki) polysaccharide extract prevents obesity-induced diabetes in C57BL/6J mice. Int J Med Mushrooms 2023; 25:27-42. [PMID: 37075082 DOI: 10.1615/intjmedmushrooms.2023047595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Ganoderma neo-japonicum Imazeki is a medicinal mushroom consumed by the indigenous people in Malaysia as a remedy for diabetes. This study aims to validate the efficacy of G. neo-japonicum polysaccharides (GNJP) on obesity-induced type 2 diabetes mellitus (T2DM) in C57BL/6J mice. Mice were divided into seven groups; normal diet (ND)-control, high-fat-diet (HFD)-control, HFDGNJP-treated (50, 100, 200 mg/kg b.w.), HFDMET (metformin 50 mg/kg; positive-control) and ND-GNJP (200 mg/kg b.w.). Mice were administered GNJP or metformin orally for 10 weeks (thrice/week) and sacrificed after an oral glucose tolerance test. Body weight, serum biochemicals, liver histology, adipocyte gene expressions, glucose and insulin levels were measured. HFD caused obesity, dyslipidemia, and diabetes in the untreated groups. GNJP (50 mg/kg b.w.) supplementation prevented weight gain and liver steatosis, improved serum lipid profile and glucose tolerance and attenuated hyperglycemia and hyperinsulinemia more effectively when compared with the other treatment groups. The prevention of obesity and lipid dysregulation is plausibly attributed to the increased hormone-sensitive lipase and reduced Akt-1 and Ppary gene expressions while the up-regulation of AdipoQ (adiponectin), Prkag2 and Slc2a4 genes served to sensitize insulin and improve glucose uptake. Thus, supplementation with an appropriate dose of GNJP has promising efficacies in preventing HFD aka obesity-induced T2DM and associated metabolic abnormalities.
Collapse
Affiliation(s)
- Sarasvathy Subramaniam
- Mushroom Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kien Chai Ong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Vikineswary Sabaratnam
- Mushroom Research Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute of Biological Science, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Mushroom Research Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Umah Rani Kuppusamy
- Mushroom Research Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| |
Collapse
|
10
|
Tee MZ, Er YX, Easton AV, Yap NJ, Lee IL, Devlin J, Chen Z, Ng KS, Subramanian P, Angelova A, Oyesola O, Sargsian S, Ngui R, Beiting DP, Boey CCM, Chua KH, Cadwell K, Lim YAL, Loke P, Lee SC. Gut microbiome of helminth-infected indigenous Malaysians is context dependent. Microbiome 2022; 10:214. [PMID: 36476263 PMCID: PMC9727879 DOI: 10.1186/s40168-022-01385-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 10/04/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND While microbiomes in industrialized societies are well characterized, indigenous populations with traditional lifestyles have microbiomes that are more akin to those of ancient humans. However, metagenomic data in these populations remains scarce, and the association with soil-transmitted helminth infection status is unclear. Here, we sequenced 650 metagenomes of indigenous Malaysians from five villages with different prevalence of helminth infections. RESULTS Individuals from villages with higher prevalences of helminth infections have more unmapped reads and greater microbial diversity. Microbial community diversity and composition were most strongly associated with different villages and the effects of helminth infection status on the microbiome varies by village. Longitudinal changes in the microbiome in response to albendazole anthelmintic treatment were observed in both helminth infected and uninfected individuals. Inference of bacterial population replication rates from origin of replication analysis identified specific replicating taxa associated with helminth infection. CONCLUSIONS Our results indicate that helminth effects on the microbiota were highly dependent on context, and effects of albendazole on the microbiota can be confounding for the interpretation of deworming studies. Furthermore, a substantial quantity of the microbiome remains unannotated, and this large dataset from an indigenous population associated with helminth infections is a valuable resource for future studies. Video Abstract.
Collapse
Affiliation(s)
- Mian Zi Tee
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Yi Xian Er
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Alice V Easton
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Nan Jiun Yap
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Ii Li Lee
- Kulliyyah of Medicine and Health Sciences, University Islam Antarabangsa Sultan Abdul Halim Mu'adzam Shah, 09300, Kuala Ketil, Kedah, Malaysia
| | - Joseph Devlin
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Ze Chen
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Kee Seong Ng
- Department of Gastroenterology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Poorani Subramanian
- Bioinformatics and Computational Biosciences Branch, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Angelina Angelova
- Bioinformatics and Computational Biosciences Branch, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Oyebola Oyesola
- Type 2 Immunity Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA
| | - Shushan Sargsian
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Romano Ngui
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Daniel P Beiting
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Ken Cadwell
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, USA
- Division of Gastroenterology, Department of Medicine, New York University Langone Health, New York, NY, USA
| | - Yvonne Ai Lian Lim
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia.
| | - P'ng Loke
- Type 2 Immunity Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA.
| | - Soo Ching Lee
- Type 2 Immunity Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA.
| |
Collapse
|
11
|
Arumugam B, Tan PK, Kuppusamy UR, Chua KH. Emerging Strategies to Improve the Stability and Bioavailability of Insulin: An Update on Formulations and Delivery Approaches. Curr Drug Deliv 2022; 20:1141-1162. [PMID: 36330644 DOI: 10.2174/1567201820666221102094433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 08/29/2022] [Accepted: 10/03/2022] [Indexed: 11/06/2022]
Abstract
Abstract:
One of the primary goals of diabetes management is to maintain blood glucose levels within a normal range, and insulin plays a vital role in achieving this. All Type 1 DM patients and advanced Type 2 DM patients require insulin. Insulin is administered subcutaneously, which may cause patient discomfort from the use of needles. Therefore, developing alternative routes of insulin administration has always been a major focus of diabetes research. This review aims to provide an update on the insulin formulations and delivery routes as well as strategies used to improve its stability and bioavailability for the treatment of diabetes.
Collapse
Affiliation(s)
- Bavani Arumugam
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Pak Kheong Tan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Umah Rani Kuppusamy
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| |
Collapse
|
12
|
Wong LP, Tay ST, Chua KH, Goh XT, Alias H, Zheng Z, Zhao Q, Wu T, Xia N, Hu Z, Lin Y. Serological Evidence of Hepatitis E Virus (HEV) Infection Among Ruminant Farmworkers: A Retrospective Study from Malaysia. Infect Drug Resist 2022; 15:5533-5541. [PMID: 36164335 PMCID: PMC9508706 DOI: 10.2147/idr.s367394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/27/2022] [Indexed: 11/23/2022] Open
Abstract
Background As scant data are available about Hepatitis E virus (HEV) infection in Malaysia, this study aimed to determine the seroprevalence of HEV amongst ruminant farmworkers in Malaysia. Methods A total of 87 farmworkers provided serum samples, which were collected from eight farms. All serum samples were tested for anti-HEV IgG and anti-HEV IgM by an enzyme-linked immunosorbent assay (ELISA) using the Wantai HEV-IgG and HEV-IgM ELISA kits from Beijing Wantai Biological Pharmacy Enterprise Co., Ltd, Beijing, China. Results Farmworkers from six cattle farms, one sheep farm and one goat farm were investigated in this study. Only one farm practices zero-grazing, with the rest using rotational grazing. Of the 87 farmworkers, males comprised 83.9%, and almost half (47.1%) were aged 20-35 years old. By ethnic group, the vast majority were Malay. Most of the farmworkers have good hygiene practices; washing or changing their clothes and showering after dealing with farm animals were common. None of the farmworker serum samples had anti-HEV IgM and IgG detected (95% confidence interval (CI): 0, 0.0415). Conclusion The finding suggests that the farmworkers had no previous exposure to Hepatitis E, and were not at risk of occupational exposure to HEV infection. Our findings suggest that a zero seroprevalence of HEV infection among ruminant farmworkers in the Muslim majority country. Good farm management, hygiene practices and the absence of contact with swine-related contamination might have contributed to the no or minimal zoonotic risks of HEV amongst farmworkers surveyed in this study.
Collapse
Affiliation(s)
- Li Ping Wong
- Centre for Epidemiology and Evidence-Based Practice, Department of Social and Preventive Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, 50603, Malaysia.,Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou, Fujian, 350122, People's Republic of China
| | - Sun Tee Tay
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, 50603, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, 50603, Malaysia
| | - Xiang Ting Goh
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, 50603, Malaysia
| | - Haridah Alias
- Centre for Epidemiology and Evidence-Based Practice, Department of Social and Preventive Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, 50603, Malaysia
| | - Zizheng Zheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, 361102, People's Republic of China
| | - Qinjian Zhao
- College of Pharmacy, Chongqing Medical University, Chongqing, People's Republic of China
| | - Ting Wu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, 361102, People's Republic of China
| | - Ningshao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, 361102, People's Republic of China.,The Research Unit of Frontier Technology of Structural Vaccinology of Chinese Academy of Medical Sciences, Xiamen University, Xiamen, 361102, People's Republic of China
| | - Zhijian Hu
- Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou, Fujian, 350122, People's Republic of China
| | - Yulan Lin
- Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou, Fujian, 350122, People's Republic of China
| |
Collapse
|
13
|
Haron FN, Azazi A, Chua KH, Lim YAL, Lee PC, Chew CH. In silico structural modeling and quality assessment of Plasmodium knowlesi apical membrane antigen 1 using comparative protein models. Trop Biomed 2022; 39:394-401. [PMID: 36214436 DOI: 10.47665/tb.39.3.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Plasmodium knowlesi is the most common zoonotic parasite associated with human malaria infection in Malaysia. Apical membrane antigen 1 (AMA1) protein in the parasite plays a critical role in parasite invasion into host cells. To date, there is no complete three-dimensional ectodomain structure of P. knowlesi AMA1 (PkAMA1) protein. The knowledge of a protein structure is important to understand the protein molecular functions. Three in silico servers with respective structure prediction methods were used in this study, i.e., SWISS-MODEL for homology modeling and Phyre2 for protein threading, which are template-based modeling, while I-TASSER for template-free ab initio modeling. Two query sequences were used in the study, i.e., native ectodomain of PkAMA1 strain H protein designated as PkAMA1-H and a modified PkAMA1 (mPkAMA1) protein sequence in adaptation for Pichia pastoris expression. The quality of each model was assessed by ProSA-web, QMEAN and SAVES v6.0 (ERRAT, Verify3D and Ramachandran plot) servers. Generated models were then superimposed with two models of Plasmodium AMA1 deposited in Protein Data Bank (PDB), i.e., PkAMA1 (4UV6.B) and Plasmodium vivax AMA1 (PvAMA1, 1W81) protein structures for similarity assessment, quantified by root-meansquare deviation (RMSD) value. SWISS-MODEL, Phyre2 and I-TASSER server generated two, one and five models, respectively. All models are of good quality according to ProSA-web assessment. Based on the average values of model quality assessment and superimposition, the models that recorded highest values for most parameters were selected as best predicted models, i.e., model 2 for both PkAMA1-H and mPkAMA1 from SWISS-MODEL as well as model 1 of PkAMA1-H and model 3 of mPkAMA1 from I-TASSER. Template-based method is useful if known template is available, but template-free method is more suitable if there is no known available template. Generated models can be used as guidance in further protein study that requires protein structural data, i.e., protein-protein interaction study.
Collapse
Affiliation(s)
- F N Haron
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| | - A Azazi
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| | - K H Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Y A L Lim
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - P C Lee
- Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
- Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
| | - C H Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| |
Collapse
|
14
|
Tee MZ, Lee SC, Er YX, Yap NJ, Ngui R, Easton AV, Siow VWY, Ng KS, Boey CCM, Chua KH, Cadwell K, Loke P, Lim YAL. Efficacy of triple dose albendazole treatment for soil-transmitted helminth infections. PLoS One 2022; 17:e0272821. [PMID: 35960935 PMCID: PMC9374461 DOI: 10.1371/journal.pone.0272821] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 07/26/2022] [Indexed: 11/18/2022] Open
Abstract
In Malaysia, soil-transmitted helminth (STH) infections still persist among indigenous communities. In the past, local studies have focused mostly on epidemiologic aspects of STH infections with a scarcity of information on the efficacy of deworming treatment. The present study consisted of 2 phases: a cross-sectional phase on current epidemiological status and risk factors of STH infections and a longitudinal study over 6 weeks on triple dose albendazole efficacy against STH infections. A total of 253 participants were recruited at baseline and a pre-tested questionnaire was administered to obtain information on socio-demographics, environmental and behavioural risk factors. Stool samples were evaluated using a modified Kato-Katz technique. Cure rate (CR) and egg reduction rate (ERR) were assessed at 3 weeks following a 3-day course of 400mg albendazole treatment and infection status were observed again at 6 weeks. Baseline positivity of trichuriasis, ascariasis and hookworm infections were 56.1%, 11.9% and 20.2%, respectively. Multivariate analysis showed age below 18 years old (P = 0.004), without latrine in house (P = 0.042) and indiscriminate defecation (P = 0.032) were associated with STH infections. In the longitudinal study (N = 89), CR for trichuriasis was 64.6%, while CR of 100% was observed for both ascariasis and hookworm. ERR was above 90% for all three STH species. A rapid increased of Trichuris trichiura egg output was observed at 6 weeks. In conclusion, STH infections are highly prevalent among indigenous communities. Children and teenagers, poor sanitation and hygiene behaviour were determinants for STH infections. Triple dose albendazole is found to be efficacious against Ascaris lumbricoides and hookworm infections but has moderate curative effect with high ERR against T. trichiura. Although triple dose albendazole regimen has logistic challenges and may not be a routine option, consideration of this treatment regime may still be necessary in selective communities to reduce high intensity of T. trichiura infection.
Collapse
Affiliation(s)
- Mian Zi Tee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Soo Ching Lee
- Type 2 Immunity Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States of America
| | - Yi Xian Er
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Nan Jiun Yap
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Romano Ngui
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Alice V. Easton
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, United States of America
| | - Vinnie Wei Yin Siow
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kee Seong Ng
- Department of Gastroenterology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | | | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ken Cadwell
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, United States of America
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, United States of America
- Division of Gastroenterology, Department of Medicine, New York University Langone Health, New York, NY, United States of America
| | - P’ng Loke
- Type 2 Immunity Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States of America
- * E-mail: (YALL); (PL)
| | - Yvonne Ai Lian Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- * E-mail: (YALL); (PL)
| |
Collapse
|
15
|
Kuan SW, Chua KH, Tan EW, Tan LK, Loch A, Kee BP. Whole mitochondrial genome sequencing of Malaysian patients with cardiomyopathy. PeerJ 2022; 10:e13265. [PMID: 35441061 PMCID: PMC9013480 DOI: 10.7717/peerj.13265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/23/2022] [Indexed: 01/13/2023] Open
Abstract
Cardiomyopathy (CMP) constitutes a diverse group of myocardium diseases affecting the pumping ability of the heart. Genetic predisposition is among the major factors affecting the development of CMP. Globally, there are over 100 genes in autosomal and mitochondrial DNA (mtDNA) that have been reported to be associated with the pathogenesis of CMP. However, most of the genetic studies have been conducted in Western countries, with limited data being available for the Asian population. Therefore, this study aims to investigate the mutation spectrum in the mitochondrial genome of 145 CMP patients in Malaysia. Long-range PCR was employed to amplify the entire mtDNA, and whole mitochondrial genome sequencing was conducted on the MiSeq platform. Raw data was quality checked, mapped, and aligned to the revised Cambridge Reference Sequence (rCRS). Variants were named, annotated, and filtered. The sequencing revealed 1,077 variants, including 18 novel and 17 CMP and/or mitochondrial disease-associated variants after filtering. In-silico predictions suggested that three of the novel variants (m.8573G>C, m.11916T>A and m.11918T>G) in this study are potentially pathogenic. Two confirmed pathogenic variants (m.1555A>G and m.11778G>A) were also found in the CMP patients. The findings of this study shed light on the distribution of mitochondrial mutations in Malaysian CMP patients. Further functional studies are required to elucidate the role of these variants in the development of CMP.
Collapse
Affiliation(s)
- Sheh Wen Kuan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - E-Wei Tan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Lay Koon Tan
- National Heart Institute, Kuala Lumpur, Malaysia
| | - Alexander Loch
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
16
|
Cheng A, Harikrishna JA, Redwood CS, Lit LC, Nath SK, Chua KH. Genetics Matters: Voyaging from the Past into the Future of Humanity and Sustainability. Int J Mol Sci 2022; 23:ijms23073976. [PMID: 35409335 PMCID: PMC8999725 DOI: 10.3390/ijms23073976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/21/2022] [Accepted: 03/30/2022] [Indexed: 12/02/2022] Open
Abstract
The understanding of how genetic information may be inherited through generations was established by Gregor Mendel in the 1860s when he developed the fundamental principles of inheritance. The science of genetics, however, began to flourish only during the mid-1940s when DNA was identified as the carrier of genetic information. The world has since then witnessed rapid development of genetic technologies, with the latest being genome-editing tools, which have revolutionized fields from medicine to agriculture. This review walks through the historical timeline of genetics research and deliberates how this discipline might furnish a sustainable future for humanity.
Collapse
Affiliation(s)
- Acga Cheng
- Institute of Biological Science, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia; (A.C.); (J.A.H.)
| | - Jennifer Ann Harikrishna
- Institute of Biological Science, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia; (A.C.); (J.A.H.)
- Centre for Research in Biotechnology for Agriculture, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Charles S. Redwood
- Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK;
| | - Lei Cheng Lit
- Department of Physiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia;
| | - Swapan K. Nath
- Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
- Correspondence: (S.K.N.); (K.H.C.)
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
- Correspondence: (S.K.N.); (K.H.C.)
| |
Collapse
|
17
|
Mariappan V, Ngoi ST, Lim YAL, Ngui R, Chua KH, Teh CSJ. Genotypic and phenotypic characterization of Escherichia coli isolated from indigenous individuals in Malaysia. Iran J Basic Med Sci 2022; 25:468-473. [PMID: 35656079 PMCID: PMC9150813 DOI: 10.22038/ijbms.2022.61612.13637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/14/2022] [Indexed: 11/17/2022]
Abstract
Objectives The occurrence of asymptomatic verocytotoxin (VT)-producing Escherichia coli (VTEC) infections among humans in recent years is posing a high risk to public health. Thus, the role of asymptomatic human carriers as a source of dissemination should not be underestimated. This study aimed to elucidate the phenotypic and genotypic characteristics of E. coli in the stool samples collected from indigenous individuals in Malaysia. Materials and Methods E. coli strains (n=108) were isolated from stool samples obtained from 41 indigenous individuals. All strains were subjected to Repetitive Extragenic Palindromic-Polymerase Chain Reaction (REP-PCR) typing and confirmation of VTEC variants. Non-duplicate strains were selected based on REP-PCR profiles and further subjected to antimicrobial susceptibility test (AST). The genotypic and phenotypic characteristics of the strains were then correlated with the demographic data of the subjects. Results A total of 66 REP-PCR profiles grouped in 53 clusters (F=85%) were obtained. Four genetically distinct strains were confirmed as VTEC (eaeA-positive). The predominant resistance was against ampicillin (34.2%), followed by trimethoprim-sulfamethoxazole (32.9%), ampicillin-sulbactam (5.5%), and ciprofloxacin (1.4%). All isolates were sensitive to amoxicillin-clavulanate, cefuroxime, ceftriaxone, imipenem, and meropenem. Conclusion Genetically diverse E. coli and VTEC strains were found to colonize the intestines of the indigenous populations. This study is important for the prospective surveillance of E. coli among the indigenous individuals in Malaysia, especially in asymptomatic VTEC infection and antimicrobial resistance phenomenon.
Collapse
Affiliation(s)
- Vanitha Mariappan
- Centre of Toxicology and Health Risk Studies (CORE), Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 50300 Kuala Lumpur, Malaysia ,Corresponding authors: Vanitha Mariappan. Centre of Toxicology and Health Risk Studies (CORE), Faculty of Health Sciences, National University of Malaysia, 50300 Kuala Lumpur, Malaysia. ; Cindy Shuan Ju Teh. Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Soo Tein Ngoi
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Yvonne Ai Lian Lim
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia,Centre for Malaysian Indigenous Studies (CMIS), Universiti Malaya, Kuala Lumpur, Malaysia
| | - Romano Ngui
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia,Corresponding authors: Vanitha Mariappan. Centre of Toxicology and Health Risk Studies (CORE), Faculty of Health Sciences, National University of Malaysia, 50300 Kuala Lumpur, Malaysia. ; Cindy Shuan Ju Teh. Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.
| |
Collapse
|
18
|
Puah SM, Puthucheary SDA, Chua KH. Virulence Profiles Among Gastrointestinal and Extraintestinal Clinical Isolates of Plesiomonas shigelloides . Jpn J Infect Dis 2022; 75:407-410. [DOI: 10.7883/yoken.jjid.2021.477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Malaysia
| | | | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Malaysia
| |
Collapse
|
19
|
Puah SM, Fong SP, Kee BP, Puthucheary SD, Chua KH. Molecular identification and biofilm-forming ability of Elizabethkingia species. Microb Pathog 2021; 162:105345. [PMID: 34896547 DOI: 10.1016/j.micpath.2021.105345] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 11/30/2021] [Accepted: 12/01/2021] [Indexed: 11/17/2022]
Abstract
Recently, Elizabethkingia species have gained attention as a cause of life-threatening infections. The identification via phenotypic methods of three important species- Elizabethkingia meningoseptica, E. anophelis and E. miricola is difficult. Our objectives were to re-assess 30 archived Flavobacterium meningosepticum isolates using 16S rRNA gene sequencing, ERIC-PCR, and biofilm formation assay. Twenty-four isolates were re-identified as E. anophelis and 6 as E. miricola. All of them had the ability to form biofilm as shown in microtiter plate assay based on crystal violet staining. Overall, E. anophelis had a higher specific biofilm formation index compared to E. miricola. A total of 42% (10 out of 24) of E. anophelis were classified as strong, 29% (7 out of 24) as moderate and 29% (7 out of 24) as weak biofilm producers. E. miricola, 17% (1 out of 6) isolates were strong biofilm producers, 50% (3 out of 6) moderate and 33% (2 out of 6) were weak producers. E. anophelis from tracheal secretions were significantly associated with (p = 0.0361) strong biofilm formation. In summary, this study showed that the isolates originally identified as F. meningosepticum were re-classified using the 16S rRNA gene as one of two Elizabethkingia species. The ability of E. anophelis to form strong biofilm in endotracheal tubes indicates their probable role in the pathogenesis of Elizabethkingia infections.
Collapse
Affiliation(s)
- Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Sam Pei Fong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - S D Puthucheary
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| |
Collapse
|
20
|
Azazi A, Haron FN, Chua KH, Lim YAL, Lee PC, Chew CH. Bioinformatics characterization of Plasmodium knowlesi apical membrane antigen 1 (PkAMA1) for multi-epitope vaccine design. Trop Biomed 2021; 38:265-275. [PMID: 34362869 DOI: 10.47665/tb.38.3.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Malaria caused by Plasmodium knowlesi species has become a public health concern, especially in Malaysia. Plasmodium knowlesi parasite which originates from the macaque species, infects human through the bite of the Anopheles mosquitoes. Research on malaria vaccine has been a continuous effort to eradicate the malaria infection, yet there is no vaccine against P. knowlesi malaria to date. Apical membrane antigen 1 (AMA1) is a unique surface protein of all apicomplexan parasites that plays a crucial role in parasite-host cell invasion and thus has been a long-standing malaria vaccine candidate. The selection of protective epitopes in silico has led to significant advances in the design of the vaccine. The present study aimed to employ bioinformatics tools to predict the potential immunogenic B- and T-cell epitopes in designing malaria vaccine targeting P. knowlesi AMA1 (PkAMA1). B-cell epitopes were predicted using four bioinformatics tools, i.e., BepiPred, ABCpred, BcePred, and IEDB servers whereas T-cell epitopes were predicted using two bioinformatics servers, i.e., NetMHCpan4.1 and NetMHCIIpan-4.0 targeting human major histocompatibility complex (MHC) class I and class II molecules, respectively. The antigenicity of the selected epitopes computed by both B- and T-cell predictors were further analyzed using the VaxiJen server. The results demonstrated that PkAMA1 protein encompasses multi antigenic regions that have the potential for the development of multi-epitope vaccine. Two B- and T-cell epitopes consensus regions, i.e., NSGIRIDLGEDAEVGNSKYRIPAGKCP (codons 28-54) and KTHAASFVIAEDQNTSY RHPAVYDEKNKT (codons 122-150) at domain I (DI) of PkAMA1 were reported. Advancement of bioinformatics in characterization of the target protein may facilitate vaccine development especially in vaccine design which is costly and cumbersome process. Thus, comprehensive B-cell and T-cell epitope prediction of PkAMA1 offers a promising pipeline for the development and design of multi-epitope vaccine against P. knowlesi.
Collapse
Affiliation(s)
- A Azazi
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| | - F N Haron
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| | - K H Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Y A L Lim
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.,Centre of Excellence for Research in AIDS (CERiA), Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - P C Lee
- Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
| | - C H Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| |
Collapse
|
21
|
Mahendran R, Lim SK, Ong KC, Chua KH, Chai HC. Natural-derived compounds and their mechanisms in potential autosomal dominant polycystic kidney disease (ADPKD) treatment. Clin Exp Nephrol 2021; 25:1163-1172. [PMID: 34254206 DOI: 10.1007/s10157-021-02111-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 07/06/2021] [Indexed: 12/25/2022]
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic kidney disorder that impairs renal functions progressively leading to kidney failure. The disease affects between 1:400 and 1:1000 ratio of the people worldwide. It is caused by the mutated PKD1 and PKD2 genes which encode for the defective polycystins. Polycystins mimic the receptor protein or protein channel and mediate aberrant cell signaling that causes cystic development in the renal parenchyma. The cystic development is driven by the increased cyclic AMP stimulating fluid secretion and infinite cell growth. In recent years, natural product-derived small molecules or drugs targeting specific signaling pathways have caught attention in the drug discovery discipline. The advantages of natural products over synthetic drugs enthusiast researchers to utilize the medicinal benefits in various diseases including ADPKD. CONCLUSION Overall, this review discusses some of the previously studied and reported natural products and their mechanisms of action which may potentially be redirected into ADPKD.
Collapse
Affiliation(s)
- Rhubaniya Mahendran
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Soo Kun Lim
- Renal Division, Department of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kien Chai Ong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Hwa Chia Chai
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| |
Collapse
|
22
|
Puah SM, Goh KL, Ng HK, Chua KH. Current status of Helicobacter pylori resistance to Clarithromycin and Levofloxacin in Malaysia-findings from a molecular based study. PeerJ 2021; 9:e11518. [PMID: 34178444 PMCID: PMC8197033 DOI: 10.7717/peerj.11518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 05/04/2021] [Indexed: 12/15/2022] Open
Abstract
Background Resistance to clarithromycin and levofloxacin in Helicobacter pylori which resulted in treatment failures has become a major challenge for physicians worldwide. The resistance is mainly mediated by mutations in a specific domain of the 23S rRNA, gyrA and gyrB genes for clarithromycin and levofloxacin respectively. Hence in this study, we aimed to investigate the current status of H. pylori resistance in our hospital to these two antibiotics based on the molecular approach. Materials and Methods Gastric biopsy samples were obtained from treatment-naïve patients. Bacterial genomic DNA was extracted using a commercial kit and continued with DNA amplification using polymerase chain reaction (PCR) with specific primers. The PCR amplicons were subjected to sequencing on 23S rRNA gene targeting nucleotide positions at 2,146, 2,147, 2,186 and amino acids at gyrA positions 87 and 91 and gyrB positions 436, 438, 481, 484 to investigate the possible mutations or polymorphisms of genes that lead to clarithromycin and levofloxacin resistance respectively. Results Sixty-one urease-positive gastric biopsy samples were studied. The findings revealed the primary resistance rates to clarithromycin was 14.8% and to levofloxacin was 3.3% in our current scenario based on detection of reported resistance-related mutations of A2147G and D91N in 23S rRNA and gyrA genes, respectively. Interestingly, we found a high rate of silent mutations of the gyrA codon 87Asn (32.8%, 20/61) and two polymorphisms of the gyrB D481E (16.4%, 10/61) and R484K (21.3%, 13/61). The role of these polymorphisms in gyrB remained to be elucidated whether the levels of levofloxacin resistance are related to the position/amino acid. Conclusion The primary resistance rate of H. pylori to clarithromycin has increased compared to the previous report in Malaysia. Therefore, molecular screening could aid and is important for the selection of antibiotics for H. pylori eradication therapies.
Collapse
Affiliation(s)
- Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Khean Lee Goh
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Heng Kang Ng
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
23
|
Goh XT, Lim YAL, Lee PC, Nissapatorn V, Chua KH. Diversity and natural selection of Merozoite surface Protein-1 in three species of human malaria parasites: Contribution from South-East Asian isolates. Mol Biochem Parasitol 2021; 244:111390. [PMID: 34087264 DOI: 10.1016/j.molbiopara.2021.111390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 05/28/2021] [Accepted: 05/28/2021] [Indexed: 11/19/2022]
Abstract
The present study aimed to examine the genetic diversity of human malaria parasites (i.e., P. falciparum, P. vivax and P. knowlesi) in Malaysia and southern Thailand targeting the 19-kDa C-terminal region of Merozoite Surface Protein-1 (MSP-119). This region is essential for the recognition and invasion of erythrocytes and it is considered one of the leading candidates for asexual blood stage vaccines. However, the genetic data of MSP-119 among human malaria parasites in Malaysia is limited and there is also a need to update the current sequence diversity of this gene region among the Thailand isolates. In this study, genomic DNA was extracted from 384 microscopy-positive blood samples collected from patients who attended the hospitals or clinics in Malaysia and malaria clinics in Thailand from the year 2008 to 2016. The MSP-119 was amplified using PCR followed by bidirectional sequencing. DNA sequences identified in the present study were subjected to Median-joining network analysis with sequences of MSP-119 obtained from GenBank. DNA sequence analysis revealed that PfMSP-119 of Malaysian and Thailand isolates was not genetically conserved as high number of haplotypes were detected and positive selection was prevalent in PfMSP-119, hence questioning its suitability to be used as a vaccine candidate. A novel haplotype (Q/TNG/L) was also detected in Thailand P. falciparum isolate. In contrast, PvMSP-119 was highly conserved, however for the first time, a non-synonymous substitution (A1657S) was reported among Malaysian isolates. As for PkMSP-119, the presence of purifying selection and low nucleotide diversity indicated that it might be a potential vaccine target for P. knowlesi.
Collapse
Affiliation(s)
- Xiang Ting Goh
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Ping Chin Lee
- School of Science and Technology, University Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia
| | - Veeranoot Nissapatorn
- Research Excellence Center for Innovation and Health Products (RECIHP) and School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| |
Collapse
|
24
|
Singh B, Maiti GP, Zhou X, Fazel-Najafabadi M, Bae SC, Sun C, Terao C, Okada Y, Chua KH, Kochi Y, Guthridge JM, Zhang H, Weirauch M, James JA, Harley JB, Varshney GK, Looger LL, Nath SK. Lupus susceptibility region containing CDKN1B rs34330 mechanistically influences expression and function of multiple target genes, also linked to proliferation and apoptosis. Arthritis Rheumatol 2021; 73:2303-2313. [PMID: 33982894 DOI: 10.1002/art.41799] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 05/04/2021] [Indexed: 11/10/2022]
Abstract
OBJECTIVE A recent genome-wide association study (GWAS) reported a significant genetic association between rs34330 of cyclin-dependent kinase inhibitor 1B (CDKN1B) and risk of systemic lupus erythematosus (SLE) in Han Chinese. This study aims to validate the reported association and elucidate the biochemical mechanisms underlying the variant's effect. METHODS We performed allelic association with SLE followed by meta-analysis across 11 independent cohorts (n=28,872). We applied in silico bioinformatics and experimental validation in SLE-relevant cell lines to determine the functional consequences of rs34330. RESULTS We replicated genetic association between SLE and rs34330 (Pmeta =5.29x10-22 , OR (95% CI)=0.84 (0.81-0.87)). Follow-up bioinformatics and eQTL analysis suggest that rs34330 is located in active chromatin and potentially regulates several target genes. Using luciferase and ChIP-qPCR, we demonstrated substantial allele-specific promoter and enhancer activity, and allele-specific binding of three histone marks (H3K27ac, H3K4me3, H3K4me1), RNA pol II, CTCF, and a critical immune transcription factor (IRF-1). Chromosome conformation capture (3C) detected long-range chromatin interactions between rs34330 and the promoters of neighboring genes APOLD1 and DDX47, and effects on CDKN1B and the other target genes were directly validated by CRISPR-based genome editing. Finally, CRISPR-dCas9-based epigenetic activation/silencing confirmed these results. Gene-edited cell lines also showed higher levels of proliferation and apoptosis. CONCLUSION Collectively, these findings suggest a mechanism whereby the rs34330 risk allele (C) influences the presence of histone marks, RNA pol II, and the IRF-1 transcription factor to regulate expression of several target genes linked to proliferation and apoptosis, which potentially underlie the association of rs34330 with SLE.
Collapse
Affiliation(s)
- Bhupinder Singh
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Guru P Maiti
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Xujie Zhou
- Renal Division, Peking University First Hospital, Peking University, Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China
| | - Mehdi Fazel-Najafabadi
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Sang-Cheol Bae
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, Republic of Korea
| | - Celi Sun
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Chikashi Terao
- Laboratory for Statistical and Translational Genetics, Center for Integrative Medical Sciences, RIKEN Yokohama Institute, Yokohama, Kanagawa, Japan.,Department of Applied Genetics, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Yukinori Okada
- Department of Statistical Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yuta Kochi
- Department of Genomic Function and Diversity, Medical Research Institute, Tokyo Medical and Dental University Laboratory for Autoimmune Diseases, Center for Integrative Medical Sciences, RIKEN Yokohama Institute, Yokohama, Kanagawa, Japan
| | - Joel M Guthridge
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Peking University, Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China
| | - Matthew Weirauch
- Center for Autoimmune Genomics and Etiology (CAGE), Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, and the US Department of Veterans Affairs Medical Center, Cincinnati, OH, USA
| | - Judith A James
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - John B Harley
- Center for Autoimmune Genomics and Etiology (CAGE), Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, and the US Department of Veterans Affairs Medical Center, Cincinnati, OH, USA
| | - Gaurav K Varshney
- Genes and Human Disease Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Loren L Looger
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA, USA
| | - Swapan K Nath
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| |
Collapse
|
25
|
Jones SU, Chua KH, Chew CH, Yeo CC, Abdullah FH, Othman N, Kee BP, Puah SM. spa diversity of methicillin-resistant and -susceptible Staphylococcus aureus in clinical strains from Malaysia: a high prevalence of invasive European spa-type t032. PeerJ 2021; 9:e11195. [PMID: 33889447 PMCID: PMC8038637 DOI: 10.7717/peerj.11195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 03/09/2021] [Indexed: 12/30/2022] Open
Abstract
Background Staphylococcus aureus is one of the important pathogens causing nosocomial infection. spa typing allows identification of S. aureus clones in hospital isolates and is useful for epidemiological studies and nosocomial infection control. This study aims to investigate the spa types in Malaysian S. aureus isolates obtained from various clinical specimens. Method A total of 89 methicillin-resistant S. aureus (MRSA) [pus (n = 55), blood (n = 27), respiratory (n = 5), eye (n = 2)] isolates and 109 methicillin-susceptible S. aureus (MSSA) [pus (n = 79), blood (n = 24), respiratory (n = 3), eye (n = 2) and urine (n = 1)] isolates were subjected to spa typing with sequences analysed using BioNumerics version 7. Results The spa sequence was successfully amplified from 77.8% of the strains (154/198) and 47 known spa types were detected. The distribution of known spa types in MRSA (36.2%, 17/47) was less diverse than in MSSA (70.2%, 33/47). The most predominant spa types were t032 (50%) in MRSA, and t127 (19%) and t091 (16.7%) in MSSA, respectively. spa type t091 in MSSA was significantly associated with skin and soft tissue infections (p = 0.0199). Conclusion The previously uncommon spa type t032 was detected in the Malaysian MRSA strains, which also corresponded to the most common spa type in Europe and Australia, and has replaced the dominant spa type t037 which was reported in Malaysia in 2010.
Collapse
Affiliation(s)
- Sherry Usun Jones
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus, Terengganu, Malaysia
| | - Chew Chieng Yeo
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia
| | | | - Norlela Othman
- Department of Pathology, Hospital Sultanah Nur Zahirah, Kuala Terengganu, Terengganu, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
26
|
Lee SC, Tang MS, Lim YAL, Choy SH, Kurtz ZD, Cox LM, Gundra UM, Cho I, Bonneau R, Blaser MJ, Chua KH, Loke P. Correction: Helminth Colonization Is Associated with Increased Diversity of the Gut Microbiota. PLoS Negl Trop Dis 2021; 15:e0009325. [PMID: 33826625 PMCID: PMC8026030 DOI: 10.1371/journal.pntd.0009325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pntd.0002880.].
Collapse
|
27
|
Lau MY, Teng FE, Chua KH, Ponnampalavanar S, Chong CW, Abdul Jabar K, Teh CSJ. Molecular Characterization of Carbapenem Resistant Klebsiella pneumoniae in Malaysia Hospital. Pathogens 2021; 10:pathogens10030279. [PMID: 33801250 PMCID: PMC8001961 DOI: 10.3390/pathogens10030279] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/19/2021] [Accepted: 02/25/2021] [Indexed: 11/16/2022] Open
Abstract
The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) is a great concern, as carbapenems are the last-line therapy for multidrug-resistant Gram-negative bacteria infections. This study aims to report the epidemiology of CRKP in a teaching hospital in Malaysia based on the molecular genotypic and clinical characteristics of the isolates. Sixty-three CRKP strains were isolated from a tertiary teaching hospital from January 2016 until August 2017. Carbapenemase genes were detected in 55 isolates, with blaOXA-48 (63.5%) as the predominant carbapenemase gene, followed by blaNDM (36.5%). At least one porin loss was detected in nine isolates. Overall, 63 isolates were divided into 30 clusters at similarity of 80% with PFGE analysis. Statistical analysis showed that in-hospital mortality was significantly associated with the usage of central venous catheter, infection or colonization by CRKP, particularly NDM-producers. In comparison, survival analysis using Cox proportional hazards regression identified a higher hazard ratio for patients with a stoma and patients treated with imipenem but a lower hazard ratio for patients with NDM-producing CRKP. OXA-48 carbapenemase gene was the predominant carbapenemase gene in this study. As CRKP infection could lead to a high rate of in-hospital mortality, early detection of the isolates was important to reduce their dissemination.
Collapse
Affiliation(s)
- Min Yi Lau
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (M.Y.L.); (F.E.T.)
| | - Fui Enn Teng
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (M.Y.L.); (F.E.T.)
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Sasheela Ponnampalavanar
- Department of Infectious Diseases, University Malaya Medical Centre, Kuala Lumpur 50603, Malaysia;
| | - Chun Wie Chong
- School of Pharmacy, Monash University Malaysia, Subang Jaya 47500, Malaysia;
- Centre for Translational Research, Institute of Research, Development and Innovation, Kuala Lumpur 57000, Malaysia
| | - Kartini Abdul Jabar
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (M.Y.L.); (F.E.T.)
- Correspondence: (K.A.J.); (C.S.J.T.); Tel.: +603-79676674 (C.S.J.T.)
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia; (M.Y.L.); (F.E.T.)
- Correspondence: (K.A.J.); (C.S.J.T.); Tel.: +603-79676674 (C.S.J.T.)
| |
Collapse
|
28
|
Teh CSJ, Lau MY, Chong CW, Ngoi ST, Chua KH, Lee WS, Thong KL. One-step differential detection of Salmonella enterica serovar Typhi, serovar Paratyphi A and other Salmonella spp. by using a quadruplex real-time PCR assay. J Microbiol Methods 2021; 183:106184. [PMID: 33662480 DOI: 10.1016/j.mimet.2021.106184] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 12/14/2022]
Abstract
Diseases caused by typhoidal and non-typhoidal Salmonella remain a considerable threat to both developed and developing countries. Based on the clinical symptoms and serological tests, it is sometimes difficult to differentiate the Salmonella enterica serovar Paratyphi A (S. enterica serovar Paratyphi A) from serovar Typhi (S. enterica serovar Typhi). In this study, we developed a quadruplex real-time polymerase chain reaction (PCR) assay with an internal amplification control (IAC), to simultaneously differentiate S. enterica serovar Paratyphi A from serovar Typhi and to detect other Salmonella serovars which cause salmonellosis in humans. This assay was evaluated on 155 salmonellae and non-salmonellae strains and demonstrated 100% specificity in species differentiation. Inclusion of an IAC did not affect the efficiency of the assay. Further evaluation using a blind test on spiked stool, blood and food specimens showed that the detection limit was at 103 -104 CFU/mL (or g) and a high PCR efficiency with different targets (R2 > 0.99), except for S. enterica serovar Paratyphi A in blood. This assay has been applied to clinical specimens to detect the causative agents of gastrointestinal infections and has successfully identified 6 salmonellosis patients from the 50 diarrhoea patients. The quadruplex real-time PCR developed in this study could enhance the detection and differentiation of salmonellae. This assay could be applied to stools, blood and food based on the notable performance in the simulation tests and field evaluation.
Collapse
Affiliation(s)
- Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Min Yi Lau
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Chun Wie Chong
- School of Pharmacy, Monash University Malaysia, 47500 Bandar Sunway, Selangor, Malaysia
| | - Soo Tein Ngoi
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Way Seah Lee
- Department of Paediatrics, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kwai Lin Thong
- Nanotechnology & Catalysis Research Centre, Deputy Vice Chancellor (Research & Innovation), University of Malaya, 50603 Kuala Lumpur, Malaysia
| |
Collapse
|
29
|
Nallappan D, Chua KH, Ong KC, Chong CW, Teh CSJ, Palanisamy UD, Kuppusamy UR. Amelioration of high-fat diet-induced obesity and its associated complications by a myricetin derivative-rich fraction from Syzygium malaccense in C57BL/6J mice. Food Funct 2021; 12:5876-5891. [PMID: 34019055 DOI: 10.1039/d1fo00539a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Obesity is a driving factor in the onset of metabolic disorders. This study aims to investigate the effects of the myricetin derivative-rich fraction (MD) from Syzygium malaccense leaf extract on high-fat diet (HFD)-induced obesity and its associated complications and its influence on uncoupling protein-1 (UCP-1) and gut microbiota in C57BL/6J mice. Mice were randomly assigned into four groups (n = 6) and given a normal diet (ND) or high-fat diet (HFD) for 10 weeks to induce obesity. The HFD groups (continued with HFD) were administered 50 mg kg-1 MD (treatment), 50 mg kg-1 metformin (positive control) and normal saline (HFD and ND controls) daily for four weeks via oral gavage. The ten-week HFD-feeding resulted in hyperglycemia and elevated urinary oxidative indices. The subsequent MD administration caused significant weight reduction without appetite suppression and amelioration of insulin resistance, steatosis and dyslipidemia. Besides, MD significantly reduced lipid hydroperoxides and protein carbonyls in tissue homogenates and urine and elevated Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP) and reduced glutathione (GSH) and thus, alleviated oxidative stress. The weight reduction was correlated with downregulation of inflammatory markers and the increased UCP-1 level, suggesting weight loss plausibly through thermogenesis. The Akkermansia genus (reflects improved metabolic status) in the HFD50 group was more abundant than that in the HFD group while the non-enzymatic antioxidant markers were strongly associated with UCP-1. In conclusion, MD ameliorates obesity and its related complications possibly via the upregulation of UCP-1 and increased abundance of Akkermansia genus and is promising as a therapeutic agent in the treatment of obesity and its associated metabolic disorders.
Collapse
Affiliation(s)
- Devi Nallappan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Kien Chai Ong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia. and Laboratory Animal Centre, Centre of Research Services, Institute of Research Management & Monitoring, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Chun Wie Chong
- School of Pharmacy, Monash University Malaysia, 47500 Bandar Sunway, Selangor, Malaysia
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Uma Devi Palanisamy
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Bandar Sunway, Selangor, Malaysia
| | - Umah Rani Kuppusamy
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| |
Collapse
|
30
|
Chong ETJ, Neoh JWF, Lau TY, Lim YAL, Chai HC, Chua KH, Lee PC. Genetic diversity of circumsporozoite protein in Plasmodium knowlesi isolates from Malaysian Borneo and Peninsular Malaysia. Malar J 2020; 19:377. [PMID: 33092594 PMCID: PMC7579551 DOI: 10.1186/s12936-020-03451-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 10/16/2020] [Indexed: 11/25/2022] Open
Abstract
Background Understanding the genetic diversity of candidate genes for malaria vaccines such as circumsporozoite protein (csp) may enhance the development of vaccines for treating Plasmodium knowlesi. Hence, the aim of this study is to investigate the genetic diversity of non-repeat regions of csp in P. knowlesi from Malaysian Borneo and Peninsular Malaysia. Methods A total of 46 csp genes were subjected to polymerase chain reaction amplification. The genes were obtained from P. knowlesi isolates collected from different divisions of Sabah, Malaysian Borneo, and Peninsular Malaysia. The targeted gene fragments were cloned into a commercial vector and sequenced, and a phylogenetic tree was constructed while incorporating 168 csp sequences retrieved from the GenBank database. The genetic diversity and natural evolution of the csp sequences were analysed using MEGA6 and DnaSP ver. 5.10.01. A genealogical network of the csp haplotypes was generated using NETWORK ver. 4.6.1.3. Results The phylogenetic analysis revealed indistinguishable clusters of P. knowlesi isolates across different geographic regions, including Malaysian Borneo and Peninsular Malaysia. Nucleotide analysis showed that the csp non-repeat regions of zoonotic P. knowlesi isolates obtained in this study underwent purifying selection with population expansion, which was supported by extensive haplotype sharing observed between humans and macaques. Novel variations were observed in the C-terminal non-repeat region of csp. Conclusions The csp non-repeat regions are relatively conserved and there is no distinct cluster of P. knowlesi isolates from Malaysian Borneo and Peninsular Malaysia. Distinctive variation data obtained in the C-terminal non-repeat region of csp could be beneficial for the design and development of vaccines to treat P. knowlesi.
Collapse
Affiliation(s)
- Eric Tzyy Jiann Chong
- Biotechnology Programme, Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, 88400, Kota Kinabalu, Sabah, Malaysia
| | - Joveen Wan Fen Neoh
- Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400, Kota Kinabalu, Sabah, Malaysia
| | - Tiek Ying Lau
- Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400, Kota Kinabalu, Sabah, Malaysia
| | - Yvonne Ai-Lian Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.,Centre of Excellence for Research in AIDS (CERiA), University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Hwa Chia Chai
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Ping-Chin Lee
- Biotechnology Programme, Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, 88400, Kota Kinabalu, Sabah, Malaysia.
| |
Collapse
|
31
|
Cheok YY, Puah SM, Chua KH, Tan JAMA. Isolation and molecular identification of Aeromonas species from the tank water of ornamental fishes. Acta Vet Hung 2020; 68:130-139. [PMID: 33055305 DOI: 10.1556/004.2020.00029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 03/09/2020] [Indexed: 11/19/2022]
Abstract
Aeromonads are recognised as important pathogens of fishes. In this study, ten water samples were randomly collected from pet shops' fish tanks and home aquaria inhabited by several fish species (silver arowana, koi, goldfish, catfish, pictus fish, silver shark and silver dollar fish). Altogether 298 colonies were isolated using Aeromonas selective agar. A total of 154 isolates were then confirmed as belonging to the genus Aeromonas using the GCAT gene. Using ERIC-PCR, a total of 40 duplicate isolates were excluded from the study and 114 isolates were subjected to PCR-RFLP targeting the RNA polymerase sigma factor (rpoD) gene using lab-on-chip. A total of 13 different Aeromonas species were identified. The most prevalent species were A. veronii (27%, 31/114), followed by A. dhakensis (17%, 19/114), A. finlandiensis (9%, 10/114), A. caviae (8%, 9/114), A. hydrophila (4%, 4/114), A. jandaei (4%, 4/114), A. rivuli (3%, 3/114), A. enteropelogens (2%, 2/114), A. tecta (2%, 2/114), A. allosaccharophila (1%, 1/114), A. eucrenophila (1%, 1/114), A. media (1%, 1/114) and A. diversa (1%, 1/114). Twenty-six isolates (23%) were unidentifiable at species level. The present study demonstrates that Aeromonas species are highly diverse in freshwater fish tanks, and suggests the potential risks posed by the isolated bacteria to the health of ornamental fish species.
Collapse
Affiliation(s)
- Yi Ying Cheok
- 1Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Suat Moi Puah
- 1Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Kek Heng Chua
- 1Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | | |
Collapse
|
32
|
Lau MY, Ponnampalavanar S, Lee WS, Jabar KA, Chua KH, Idris N, Chong CW, Yap PSX, Teh CSJ. First detection of Klebsiella quasipneumoniae producing OXA-181 carbapenemase in Malaysia. J Infect Chemother 2020; 26:1058-1061. [DOI: 10.1016/j.jiac.2020.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 10/24/2022]
|
33
|
Tan TK, Lim YAL, Chua KH, Chai HC, Low VL, Bathmanaban P, Affendi S, Wang D, Panchadcharam C. Characterization of benzimidazole resistance in Haemonchus contortus: integration of phenotypic, genotypic and proteomic approaches. Parasitol Res 2020; 119:2851-2862. [PMID: 32651637 DOI: 10.1007/s00436-020-06790-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 06/28/2020] [Indexed: 11/29/2022]
Abstract
The field strain of Haemonchus contortus has a long history of anthelmintic resistance. To understand this phenomenon, the benzimidazole resistance profile was characterized from the Malaysian field-resistant strain by integrating phenotypic, genotypic and proteomic approaches. The faecal egg count reduction test (FECRT) demonstrated that benzimidazole resistance was at a critical level in the studied strain. The primary resistance mechanism was attributed to F200Y mutation in the isotype 1 β-tubulin gene as revealed by AS-PCR and direct sequencing. Furthermore, the protein response of the resistant strain towards benzimidazole (i.e., albendazole) treatment was investigated via two-dimensional difference gel electrophoresis (2D-DIGE) and tandem liquid chromatography-mass spectrometry (LC-MS/MS). These investigations illustrated an up-regulation of antioxidant (i.e., ATP-binding region and heat-shock protein 90, superoxide dismutase) and metabolic (i.e., glutamate dehydrogenase) enzymes and down-regulation of glutathione S-transferase, malate dehydrogenase, and other structural and cytoskeletal proteins (i.e., actin, troponin T). Findings from this study are pivotal in updating the current knowledge on anthelmintic resistance and providing new insights into the defence mechanisms of resistant nematodes towards drug treatment.
Collapse
Affiliation(s)
- Tiong Kai Tan
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. .,Centre of Excellence for Research in AIDS (CERIA), University of Malaya, Kuala Lumpur, Malaysia.
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Hwa Chia Chai
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Van Lun Low
- Tropical Infectious Diseases Research and Education Centre (TIDREC), University of Malaya, Kuala Lumpur, Malaysia
| | | | - Sarah Affendi
- Tropical Infectious Diseases Research and Education Centre (TIDREC), University of Malaya, Kuala Lumpur, Malaysia
| | - Daryi Wang
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Chandrawathani Panchadcharam
- Department of Veterinary Services, Ministry of Agriculture and Agro-Based Industry Malaysia, Federal Government Administrative Center, Putrajaya, Malaysia
| |
Collapse
|
34
|
Chua KH, Tan EW, Chai HC, Puthucheary SD, Lee PC, Puah SM. Rapid identification of melioidosis agent by an insulated isothermal PCR on a field-deployable device. PeerJ 2020; 8:e9238. [PMID: 32518734 PMCID: PMC7261116 DOI: 10.7717/peerj.9238] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/05/2020] [Indexed: 12/17/2022] Open
Abstract
Background Burkholderia pseudomallei causes melioidosis, a serious illness that can be fatal if untreated or misdiagnosed. Culture from clinical specimens remains the gold standard but has low diagnostic sensitivity. Method In this study, we developed a rapid, sensitive and specific insulated isothermal Polymerase Chain Reaction (iiPCR) targeting bimA gene (Burkholderia Intracellular Motility A; BPSS1492) for the identification of B. pseudomallei. A pair of novel primers: BimA(F) and BimA(R) together with a probe were designed and 121 clinical B. pseudomallei strains obtained from numerous clinical sources and 10 ATCC non-targeted strains were tested with iiPCR and qPCR in parallel. Results All 121 B. pseudomallei isolates were positive for qPCR while 118 isolates were positive for iiPCR, demonstrating satisfactory agreement (97.71%; 95% CI [93.45–99.53%]; k = 0.87). Sensitivity of the bimA iiPCR/POCKIT assay was 97.52% with the lower detection limit of 14 ng/µL of B. pseudomallei DNA. The developed iiPCR assay did not cross-react with 10 types of non-targeted strains, indicating good specificity. Conclusion This bimA iiPCR/POCKIT assay will undoubtedly complement other methodologies used in the clinical laboratory for the rapid identification of this pathogen.
Collapse
Affiliation(s)
- Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - E Wei Tan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Hwa Chia Chai
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - S D Puthucheary
- Faculty of Medicine, University of Malaya, University of Malaya, Kuala Lumpur, Malaysia
| | - Ping Chin Lee
- Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu, Sabah, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
35
|
Pang YL, Cheam WC, Chua KH, Lim S. Synthesis of iron modified sugarcane bagasse activated carbon for oxidation degradation of malachite green. ACTA ACUST UNITED AC 2020. [DOI: 10.1088/1755-1315/476/1/012137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
36
|
Arumugam B, Palanisamy UD, Chua KH, Kuppusamy UR. Amelioration of hyperglycemia-induced oxidative damage in ARPE-19 cells by myricetin derivatives isolated from Syzygium malaccense. J Funct Foods 2020. [DOI: 10.1016/j.jff.2020.103844] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
|
37
|
Ngui R, Hassan NA, Nordin NMS, Mohd-Shaharuddin N, Chang LY, Teh CSJ, Chua KH, Kee BP, Hoe SZ, Lim YAL. Copro-molecular study of Entamoeba infection among the indigenous community in Malaysia: A first report on the species-specific prevalence of Entamoeba in dogs. Acta Trop 2020; 204:105334. [PMID: 31926914 DOI: 10.1016/j.actatropica.2020.105334] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 12/31/2019] [Accepted: 01/05/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Entamoeba is a free-living protozoan parasitic species that infect a variety of hosts. In humans, Entamoeba histolytica is the causative agent of amoebiasis. Entamoeba species has also been reported in dogs. However, little is known about the molecular epidemiology and the specific species of this parasite in dogs globally, including Malaysia. As dogs are important companion animals for the indigenous community, and close contact with dogs is part of the natural living conditions for this community, this study aims to determine the prevalence and molecular epidemiology of Entamoeba species in human and dogs in Malaysia. METHOD The presence of Entamoeba species was examined in 504 fresh fecal samples, collected randomly from 411 humans and 93 dogs using microscopy and polymerase chain reaction (PCR) amplifying 16 s ribosomal RNA (rRNA). Data was analyzed using appropriate statistical analysis. RESULTS The microscopy data showed an overall occurrence of Entamoeba species of 26.3% (108/411) and 36.6% (34/93) in humans and dogs respectively. In humans, the most common species was a single infection of E. dispar (26.5%; 13/49), followed by E. histolytica and E. moshkovskii, (20.4% for each species respectively). Double infection of E. dispar + E. moshkovskii was detected at 10.2%, followed by E. dispar + E. histolytica (8.2%) and E. moshkovskii and E. histolytica (6.1%). 8.2% of the samples had triple infection with all three species. In animals, E. moshkovskii (46.7%) was the most common species detected, followed by E. histolytica, and E. dispar, at 20.0% and 13.3% respectively. Double infection with E. moshkovskii + E. histolytica and a triple infection were found in 2 samples (13.3%) and 1 (6.7%) sample respectively. Risk factor analysis showed that members of the community who used untreated water were more prone to be infected with Entamoeba. CONCLUSION This study provides information on the species-specific occurrence of Entamoeba infection, the potential risk factors and their zoonotic potential to humans. This is the first report to describe the molecular occurrence of Entamoeba species in dogs in Malaysia. The presence of pathogenic Entamoeba species implies that dogs could be a reservoir or mechanical host for human amoebiasis. Further studies need to be conducted to better understand the transmission dynamics and public health significance of Entamoeba species in human and animal hosts.
Collapse
|
38
|
Ngui R, Hassan NA, Chang LY, Teh SJC, Chua KH, Kee BP, Hoe SZ, Lim YAL. Toxoplasma gondii infection among selected indigenous community in Sarawak, East Malaysia. Trop Biomed 2020; 37:155-164. [PMID: 33612726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Toxoplasma gondii is an obligate intracellular protozoan parasite that causes toxoplasmosis in humans. To date, little is known about T. gondii infection among the indigenous community, particularly in East Malaysia. This study was conducted to determine the status of T. gondii infection and to investigate associated risk factors among the indigenous community of Sarawak, East Malaysia. The sociodemographic data was obtained using a pretested questionnaire. A serological test was done to detect the presence of specific IgM and IgG antibodies against T. gondii in serum samples. A nested polymerase chain reaction (PCR) was used to determine acute infection among seropositive individuals. The overall seroprevalence of T. gondii infection was 50% (95% CI = 43.3 - 56.7). From this subset, 40.1%, 5.7%, and 4.2% were positive for anti-T. Gondii IgG antibodies, IgM, and both IgG and IgM, respectively. Four seropositive samples were amplified through PCR. None of the pregnant women tested positive for T. gondii infection based on the serological and PCR assays. A significant association was found between age, low monthly household income, unemployment, usage of untreated water and close contact with T. gondii seropositive cats. These results provide basic information on T. gondii infection and may be useful for policymakers to initiate prevention and control programs, especially amongst pregnant women and women of childbearing age in the indigenous community.
Collapse
Affiliation(s)
- R Ngui
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - N A Hassan
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - L Y Chang
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S J C Teh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | | | - B P Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S Z Hoe
- Department of Physiology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Y A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| |
Collapse
|
39
|
Goh SL, Kee BP, Abdul Jabar K, Chua KH, Nathan AM, Bruyne J, Ngoi ST, Teh CSJ. Molecular detection and genotypic characterisation of Streptococcus pneumoniae isolated from children in Malaysia. Pathog Glob Health 2020; 114:46-54. [PMID: 32003298 DOI: 10.1080/20477724.2020.1719325] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Streptococcus pneumoniae (S. pneumoniae) is one of the main causative agents of pneumococcal diseases. To date, more than 90 distinct serotypes have been identified. Implementation of vaccines has caused a drastic reduction in vaccine-serotype pneumococcal diseases but increase in cases due to non-vaccine serotype has been observed in Malaysia. However, further investigation on different serotype incidence in Malaysia is needed and the rate of pneumococcal vaccination for new-born babies in Malaysia remains low. The recent emergence of drug-resistant S. pneumoniae (DRSP) has also been a global concern, especially penicillin resistance. This study determined the serotypes of S. pneumoniae strains (n = 95) isolated from nasopharyngeal specimens from children admitted to UMMC from 2013 to 2015. In accordance with previous studies, PCR result showed 40% of NT isolates were successfully typed as 3 less common serotypes, namely 9N/L, 17A, and 23B. The repetitive-element PCR (REP-PCR) result revealed genetic variations among the strains whereby five major clusters were observed at the similarity of 80% by clustering analysis based on fingerprint data. Penicillin-binding proteins (pbps) of selected isolates were studied by PCR and sequencing. Three strains with ≤19-mm diameter zone for Oxacillin Disc Diffusion (ODD) test previously were recorded to have mutation on all pbp1a, pbp2b, and pbp2x with MIC of 4 µg/ml, which were penicillin-intermediate resistance according to the CLSI breakpoints.
Collapse
Affiliation(s)
- Shu Ling Goh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kartini Abdul Jabar
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Anna Marie Nathan
- Department of Paediatrics, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Jessie Bruyne
- University Malaya Medical Centre, University Malaya Paediatric and Child Health Research Group, University of Malaya, Kuala Lumpur, Malaysia
| | - Soo Tein Ngoi
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
40
|
Wong LP, Alias H, Choy SH, Goh XT, Lee SC, Lim YAL, Kee BP, Chua KH, Kamaruzaman A, Zheng Z, Zhao Q, Wu T. The study of seroprevalence of hepatitis E virus and an investigation into the lifestyle behaviours of the aborigines in Malaysia. Zoonoses Public Health 2020; 67:263-270. [PMID: 31927794 DOI: 10.1111/zph.12681] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 11/27/2019] [Accepted: 12/07/2019] [Indexed: 01/27/2023]
Abstract
Malaysia is a non-endemic country for hepatitis E virus (HEV) infection. However, seroprevalence as high as 50% among samples of aboriginal people were reported over two decades ago. A total of 207 samples collected from seven aboriginal villages in rural settlements across two states in Malaysia were analysed for anti-HEV IgG and IgM by an enzyme-linked immunoassay. Following the detection of anti-HEV seroprevalence, we organized health outreach to inform and educate the community. Qualitative interviews were conducted with individuals tested positive for anti-HEV antibodies. Data derived from interviews and observations were used to investigate possible lifestyle behaviours associated with HEV infection. Anti-HEV IgG was detected in six samples (5.9%) from the village of Dusun Kubur. Qualitative inquiry and observation study revealed poor dietary and household hygiene, contaminated food and water, contact with animal faeces, unsanitary and domestic waste disposal, and wildlife reservoirs could be the contributing factors for transmission and acquisition of HEV infection. Investigation during health outreach is important to provide insights for future empirical research and implementation for improvement of lifestyle behaviours among the aborigines. Managing the risk of HEV infection in the aborigines may reduce the risk of HEV transmission to the local communities.
Collapse
Affiliation(s)
- Li Ping Wong
- Centre for Epidemiology and Evidence-Based Practice, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Haridah Alias
- Centre for Epidemiology and Evidence-Based Practice, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Seow Huey Choy
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Xiang Ting Goh
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Soo Ching Lee
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yvonne Ai Lian Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Adeeba Kamaruzaman
- Dean's Office, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Zizheng Zheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China
| | - Qinjian Zhao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China
| | - Ting Wu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China
| |
Collapse
|
41
|
Kee BP, Ng JG, Ng CC, Hilmi I, Goh KL, Chua KH. Genetic polymorphisms of ATG16L1 and IRGM genes in Malaysian patients with Crohn's disease. J Dig Dis 2020; 21:29-37. [PMID: 31654602 DOI: 10.1111/1751-2980.12829] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 10/15/2019] [Accepted: 10/22/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To investigate the association between genetic polymorphisms in ATG16L1 and IRGM genes and the development of Crohn's disease (CD) in Malaysian patients. METHODS Altogether 335 participants were recruited, including 85 patients with CD and 250 unrelated healthy controls, and their informed consent was obtained. Genomic DNA was extracted via a conventional phenol-chloroform extraction method. Six single nucleotide polymorphisms (SNPs) in ATG16L1 and IRGM genes were genotyped using TaqMan SNP genotyping assays. Associations between SNP and CD were determined using Fisher's exact test, odds ratio, and 95% confidence interval. Statistical power and the Hardy-Weinberg equilibrium were also calculated. RESULTS Two SNPs (rs2241880 and rs6754677) in the ATG16L1 gene were significantly associated with the onset of CD in the Malaysian population. The A allele and homozygous A/A genotype of the rs2241880 A/G polymorphism were protective against CD in the overall Malaysian and Malay population. The G allele and homozygous G/G genotype of the rs6754677 G/A polymorphism were protective in the Indian population, whereas the homozygous A/A genotype showed a risk of developing CD. The homozygous G/G genotype of IRGM rs11747270 was significantly present in the controls. However, this significance was not observed in a race-stratified analysis. All three ATG16L1 SNPs were associated with inflamed terminal ileum. IRGM rs4958847 and rs11747270 increased the risk of developing arthritis in patients with CD. CONCLUSION We found a significant association between SNP, which are located in autophagy-related genes, and CD in a Malaysian population.
Collapse
Affiliation(s)
- Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Jin Guan Ng
- Division of Genetics and Molecular Biology, Institute of Biological Science, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Ching Ching Ng
- Division of Genetics and Molecular Biology, Institute of Biological Science, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Ida Hilmi
- Division of Gastroenterology and Hepatology, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Khean Lee Goh
- Division of Gastroenterology and Hepatology, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
42
|
Goh XT, Chua KH, Kee BP, Lim YAL. Identification of Plasmodium knowlesi Merozoite Surface Protein-1 19 (PkMSP-1 19 ) novel binding peptides from a phage display library. Trop Med Int Health 2019; 25:172-185. [PMID: 31733137 DOI: 10.1111/tmi.13348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Plasmodium knowlesi, the fifth human malaria parasite, has caused mortality in humans. We aimed to identify P. knowlesi novel binding peptides through a random linear dodecapeptide phage display targeting the 19-kDa fragment of Merozoite Surface Protein-1 protein. METHODS rPkMSP-119 protein was heterologously expressed using Expresso® Solubility and Expression Screening System and competent E. cloni® 10G cells according to protocol. Three rounds of biopanning were performed on purified rPkMSP-119 to identify binding peptides towards rPkMSP-119 using Ph.D.™-12 random phage display library. Binding sites of the identified peptides to PkMSP-119 were in silico predicted using the CABS-dock web server. RESULTS Four phage peptide variants that bound to PkMSP-119 were identified after three rounds of biopanning, namely Pkd1, Pkd2, Pkd3 and Pkd4. The sequences of both Pkd1 and Pkd2 consist of a large number of histidine residues. Pkd1 showed positive binding signal with 6.1× vs. BSA control. Docking results showed that Pkd1 and Pkd2 were ideal binding peptides for PkMSP-119 . CONCLUSION We identified two novel binding peptides of PkMSP-119 , Pkd1 (HFPFHHHKLRAH) and Pkd2 (HPMHMLHKRQHG), through phage display. They provide a valuable starting point for the development of novel therapeutics.
Collapse
Affiliation(s)
- Xiang Ting Goh
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
43
|
Che Hamzah AM, Yeo CC, Puah SM, Chua KH, A Rahman NI, Abdullah FH, Othman N, Chew CH. Tigecycline and inducible clindamycin resistance in clinical isolates of methicillin-resistant Staphylococcus aureus from Terengganu, Malaysia. J Med Microbiol 2019; 68:1299-1305. [PMID: 31140965 DOI: 10.1099/jmm.0.000993] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The spread of multidrug-resistant Staphylococcus aureus is a public health concern. The inducible macrolide-lincosamide-streptogrammin B (iMLSB ) phenotype (or inducible clindamycin resistance) is associated with false clindamycin susceptibility in routine laboratory testing and may lead to treatment failure. Tigecycline resistance remains rare in S. aureus worldwide. This study aims to determine the antimicrobial susceptibility profiles of clinical isolates of S. aureus obtained from the main tertiary hospital in Terengganu state, Malaysia, from July 2016 to June 2017. The antimicrobial susceptibilities of 90 methicillin-resistant S. aureus (MRSA) and 109 methicillin-susceptible S. aureus (MSSA) isolates were determined by disc diffusion with the iMLSB phenotype determined by D-test. Multidrug resistance (MDR) and the iMLSB phenotype were more prevalent in MRSA (84.4 and 46.7 %, respectively) compared to MSSA isolates. All five tigecycline-resistant isolates were MRSA. The high incidence of MDR and the iMLSB phenotype and the emergence of tigecycline resistance in the Terengganu S. aureus isolates warrants continuous vigilance.
Collapse
Affiliation(s)
- Ainal Mardziah Che Hamzah
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| | - Chew Chieng Yeo
- Faculty of Medicine, Universiti Sultan Zainal Abidin, 20400 Kuala Terengganu, Terengganu, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Nor Iza A Rahman
- Faculty of Medicine, Universiti Sultan Zainal Abidin, 20400 Kuala Terengganu, Terengganu, Malaysia
| | - Fatimah Haslina Abdullah
- Department of Pathology, Hospital Sultanah Nur Zahirah, 20400 Kuala Terengganu, Terengganu, Malaysia
| | - Norlela Othman
- Department of Pathology, Hospital Sultanah Nur Zahirah, 20400 Kuala Terengganu, Terengganu, Malaysia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
| |
Collapse
|
44
|
Che Hamzah AM, Yeo CC, Puah SM, Chua KH, Chew CH. Staphylococcus aureus Infections in Malaysia: A Review of Antimicrobial Resistance and Characteristics of the Clinical Isolates, 1990-2017. Antibiotics (Basel) 2019; 8:E128. [PMID: 31454985 PMCID: PMC6784215 DOI: 10.3390/antibiotics8030128] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 08/19/2019] [Accepted: 08/22/2019] [Indexed: 12/31/2022] Open
Abstract
Staphylococcus aureus is an important nosocomial pathogen and its multidrug resistant strains, particularly methicillin-resistant S. aureus (MRSA), poses a serious threat to public health due to its limited therapeutic options. The increasing MRSA resistance towards vancomycin, which is the current drug of last resort, gives a great challenge to the treatment and management of MRSA infections. While vancomycin resistance among Malaysian MRSA isolates has yet to be documented, a case of vancomycin resistant S. aureus has been reported in our neighboring country, Indonesia. In this review, we present the antimicrobial resistance profiles of S. aureus clinical isolates in Malaysia with data obtained from the Malaysian National Surveillance on Antimicrobial Resistance (NSAR) reports as well as various peer-reviewed published records spanning a period of nearly three decades (1990-2017). We also review the clonal types and characteristics of Malaysian S. aureus isolates, where hospital-associated (HA) MRSA isolates tend to carry staphylococcal cassette chromosome mec (SCCmec) type III and were of sequence type (ST)239, whereas community-associated (CA) isolates are mostly SCCmec type IV/V and ST30. More comprehensive surveillance data that include molecular epidemiological data would enable further in-depth understanding of Malaysian S. aureus isolates.
Collapse
Affiliation(s)
- Ainal Mardziah Che Hamzah
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus 21300, Terengganu, Malaysia
| | - Chew Chieng Yeo
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Terengganu, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus 21300, Terengganu, Malaysia.
| |
Collapse
|
45
|
Molineros JE, Looger LL, Kim K, Okada Y, Terao C, Sun C, Zhou XJ, Raj P, Kochi Y, Suzuki A, Akizuki S, Nakabo S, Bang SY, Lee HS, Kang YM, Suh CH, Chung WT, Park YB, Choe JY, Shim SC, Lee SS, Zuo X, Yamamoto K, Li QZ, Shen N, Porter LL, Harley JB, Chua KH, Zhang H, Wakeland EK, Tsao BP, Bae SC, Nath SK. Amino acid signatures of HLA Class-I and II molecules are strongly associated with SLE susceptibility and autoantibody production in Eastern Asians. PLoS Genet 2019; 15:e1008092. [PMID: 31022184 PMCID: PMC6504188 DOI: 10.1371/journal.pgen.1008092] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 05/07/2019] [Accepted: 03/13/2019] [Indexed: 11/18/2022] Open
Abstract
Human leukocyte antigen (HLA) is a key genetic factor conferring risk of systemic lupus erythematosus (SLE), but precise independent localization of HLA effects is extremely challenging. As a result, the contribution of specific HLA alleles and amino-acid residues to the overall risk of SLE and to risk of specific autoantibodies are far from completely understood. Here, we dissected (a) overall SLE association signals across HLA, (b) HLA-peptide interaction, and (c) residue-autoantibody association. Classical alleles, SNPs, and amino-acid residues of eight HLA genes were imputed across 4,915 SLE cases and 13,513 controls from Eastern Asia. We performed association followed by conditional analysis across HLA, assessing both overall SLE risk and risk of autoantibody production. DR15 alleles HLA-DRB1*15:01 (P = 1.4x10-27, odds ratio (OR) = 1.57) and HLA-DQB1*06:02 (P = 7.4x10-23, OR = 1.55) formed the most significant haplotype (OR = 2.33). Conditioned protein-residue signals were stronger than allele signals and mapped predominantly to HLA-DRB1 residue 13 (P = 2.2x10-75) and its proxy position 11 (P = 1.1x10-67), followed by HLA-DRB1-37 (P = 4.5x10-24). After conditioning on HLA-DRB1, novel associations at HLA-A-70 (P = 1.4x10-8), HLA-DPB1-35 (P = 9.0x10-16), HLA-DQB1-37 (P = 2.7x10-14), and HLA-B-9 (P = 6.5x10-15) emerged. Together, these seven residues increased the proportion of explained heritability due to HLA to 2.6%. Risk residues for both overall disease and hallmark autoantibodies (i.e., nRNP: DRB1-11, P = 2.0x10-14; DRB1-13, P = 2.9x10-13; DRB1-30, P = 3.9x10-14) localized to the peptide-binding groove of HLA-DRB1. Enrichment for specific amino-acid characteristics in the peptide-binding groove correlated with overall SLE risk and with autoantibody presence. Risk residues were in primarily negatively charged side-chains, in contrast with rheumatoid arthritis. We identified novel SLE signals in HLA Class I loci (HLA-A, HLA-B), and localized primary Class II signals to five residues in HLA-DRB1, HLA-DPB1, and HLA-DQB1. These findings provide insights about the mechanisms by which the risk residues interact with each other to produce autoantibodies and are involved in SLE pathophysiology. The Human leukocyte antigen (HLA) region is a key genetic factor conferring risk of systemic lupus erythematosus (SLE). In spite of multiple SLE association signals identified in the HLA region, only amino-acid residues within HLA-DRB1 have been specifically described previously. In this study, we performed an imputation-based analysis on individuals with East Asian ancestry, and characterized SLE risk within the HLA region for all involved independent genes (HLA-DRB1, HLA-DPB1, HLA-DQB1, HLA-A, and HLA-B). Furthermore, we identified a characteristic SLE risk residue signature as well as a pattern of specific nRNP and Ro/La autoantibody residues located in the peptide-binding grooves, suggesting their key involvement in autoantibody production.
Collapse
Affiliation(s)
- Julio E. Molineros
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
| | - Loren L. Looger
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | - Kwangwoo Kim
- Department of Biology, Kyung Hee University, Seoul, Republic of Korea
| | - Yukinori Okada
- Department of Statistical Genetics, Osaka University Graduate School of Medicine, Osaka, Japan
- Laboratory for Statistical Analysis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
- Laboratory of Statistical Immunology, Immunology Frontier Research Center (WPI-IFReC), Osaka University, Suita, Japan
| | - Chikashi Terao
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
- Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto, Japan
- Division of Genetics, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Medical and Population Genetics, Broad Institute, Cambridge, Massachusetts, United States of America
| | - Celi Sun
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
| | - Xu-jie Zhou
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China
- Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Prithvi Raj
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Yuta Kochi
- Laboratory for Autoimmune Diseases, Center for Integrative Medical Sciences, RIKEN, Yokohama, Japan
| | - Akari Suzuki
- Laboratory for Autoimmune Diseases, Center for Integrative Medical Sciences, RIKEN, Yokohama, Japan
| | - Shuji Akizuki
- Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shuichiro Nakabo
- Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - So-Young Bang
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, Korea
| | - Hye-Soon Lee
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, Korea
| | - Young Mo Kang
- School of Medicine, Kyungpook National University Hospital, Daegu, Korea
| | - Chang-Hee Suh
- Department of Rheumatology, Ajou University Hospital, Suwon, Korea
| | - Won Tae Chung
- Dong-A University Hospital, Department of Internal Medicine, Busan, Korea
| | - Yong-Beom Park
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Jung-Yoon Choe
- Department of Rheumatology, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Seung-Cheol Shim
- Daejeon Rheumatoid & Degenerative Arthritis Center, Chungnam National University Hospital, Daejeon, Korea
| | - Shin-Seok Lee
- Department of Rheumatology, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Xiaoxia Zuo
- Department of Rheumatology and Immunology, Xiangya Hospital, Central South University, Changsha, China
| | - Kazuhiko Yamamoto
- Laboratory for Autoimmune Diseases, Center for Integrative Medical Sciences, RIKEN, Yokohama, Japan
| | - Quan-Zhen Li
- Department of Immunology and Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Nan Shen
- Department of Rheumatology and Shanghai Institute of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Center for Autoimmune Genomics and Etiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Lauren L. Porter
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | - John B. Harley
- Center for Autoimmune Genomics and Etiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- US Department of Veterans Affairs Medical Center, Cincinnati, Ohio, United States of America
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Hong Zhang
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China
- Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China
| | - Edward K. Wakeland
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Betty P. Tsao
- Division of Rheumatology and Immunology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Sang-Cheol Bae
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, Korea
- * E-mail: (SCB); (SKN)
| | - Swapan K. Nath
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
- * E-mail: (SCB); (SKN)
| |
Collapse
|
46
|
Puah SM, Puthucheary SD, Chua KH. First Report of Extended-Spectrum β-Lactamases TEM-116 and OXA-10 in Clinical Isolates of Alcaligenes Species from Kuala Lumpur, Malaysia. Jpn J Infect Dis 2019; 72:266-269. [PMID: 30918144 DOI: 10.7883/yoken.jjid.2018.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
There is an alarming increase in the prevalence of extended-spectrum β-lactamases (ESBLs) present mainly in Enterobacteriaceae and other nonfermenting gram-negative bacteria, such as Alcaligenes faecalis, which is the only species in that genus that is clinically relevant. We investigated Alcaligenes species from 7 cases (6 inpatients and one outpatient) at our tertiary-care hospital. Four patients had urinary tract infections, and one each had systemic lupus erythematosus, pulmonary stenosis, and diabetic ulcer. All 7 isolates were identified as Alcaligenes spp. based on their 16S rRNA gene sequences, and antibiotic susceptibility was determined using a Vitek 2 system with AST-GN87 cards. All the strains were resistant to cefazolin; 6 were resistant to trimethoprim/sulfamethoxazole; 5 manifested resistance to ampicillin/sulbactam, cefepime, tobramycin, ciprofloxacin, and nitrofurantoin; whereas 5 had multidrug resistance profiles. All the strains (7/7) expressed ESBL activity; PCR screening and sequencing showed evidence of genes blaTEM-116 (7/7) and blaOXA-10 (4/7), and we believe that this is the first report on the presence of TEM-116 and OXA-10 in an Alcaligenes spp. A combination of the 2 genes was present in 4 strains. All 7 strains were found to harbor at least one ESBL gene probably contributing to the drug resistance.
Collapse
Affiliation(s)
- Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya
| | | | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya
| |
Collapse
|
47
|
Subramaniam P, Jabar KA, Kee BP, Chong CW, Nathan AM, de Bruyne J, Thavagnanam S, Chua KH, Md Yusof MY, Teh CSJ. Serotypes & penicillin susceptibility of Streptococcus pneumoniae isolated from children admitted to a tertiary teaching hospital in Malaysia. Indian J Med Res 2019; 148:225-231. [PMID: 30381546 PMCID: PMC6206763 DOI: 10.4103/ijmr.ijmr_1987_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Background & objectives: Streptococcus pneumoniae (pneumococcus) is a highly invasive extracellular pathogen that causes diseases such as pneumonia, otitis media and meningitis. This study was undertaken to determine the serotype diversity and penicillin susceptibility of S. pneumoniae isolated from paediatric patients in a tertiary teaching hospital in Malaysia. Methods: A total of 125 clinical isolates collected from January 2013 to May 2015 were serotyped using seven sequential multiplex polymerase chain reactions. The susceptibility of these isolates to penicillin was also investigated. Results: Serotypes detected among the isolates were serotypes 3, 6A/B, 6C, 11/A/D/F, 15A/F, 19A, 19F, 23A, 23F, 34. Serotypes 19F and 6A/B were the most prevalent serotypes detected. Most of the S. pneumoniae were isolated from nasopharyngeal samples of children below five years of age. Majority of the isolates were penicillin susceptible. Only 5.6 per cent of the isolates were non-susceptible to penicillin, mostly of serotype 19F. Interpretation & conclusions: Our study revealed the distribution of various serotypes in S. pneumoniae isolates obtained from children in a teaching hospital at Kuala Lumpur, Malaysia and decreasing rates of penicillin resistance among them. The shifts in serotypes and susceptibility to penicillin from time to time have been observed. Continuous monitoring and surveillance are pivotal for better infection control and management of pneumococcal infections among children.
Collapse
Affiliation(s)
- Prasanna Subramaniam
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kartini Abdul Jabar
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Chun Wie Chong
- Department of Life Science, School of Pharmacy, International Medical University; Centre for Translational Research, Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia
| | - Anna Marie Nathan
- Department of Paediatrics, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Jessie de Bruyne
- Department of Paediatrics, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Surendran Thavagnanam
- Department of Paediatrics, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohd Yasim Md Yusof
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
48
|
Goh XT, Chua KH, Vythilingam I, Lee PC, Tan TC, Yap NJ, Chai HC, Nissapatorn V, Lim YAL. Genetic diversity of Merozoite Surface Protein-1 gene block 2 allelic types in Plasmodium falciparum isolates from Malaysia and Thailand. Trop Biomed 2019; 36:70-80. [PMID: 33597428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Malaria is the most common vector-borne parasitic disease in Malaysia and Thailand, especially in Malayan Borneo and along the Thailand border areas, but little is known about the genetic diversity of the parasite. Present study aims to investigate the genetic diversity of Plasmodium falciparum isolates in these two countries and eventually contributes to more effective malaria control strategies, particularly in vaccine and antimalarial treatment. One hundred and seventy three P. falciparum isolates were collected from Malaysia (n = 67) and Thailand (n = 106) and genotyped using nested PCR targeting the polymorphic region of MSP-1, block 2. Sequence analysis was conducted to investigate the allele diversity of the isolates. Three allelic families were identified in Malaysian and Thailand P. falciparum isolates, MAD20, K1 and RO33. Sequence analysis revealed that there were 5 different MAD20, 1 K1 and 2 different RO33 for Malaysian isolates. Thailand isolates exhibited greater polymorphism because there were 13 different MAD20, 6 different K1 and 2 different RO33 identified in this study. Multiclonal infections were observed for the isolates in both countries, however, low multiplicity of infection (MOI) was observed for Malaysian (1.1) and Thailand (1.2) isolates. Phylogenetic analysis showed that P. falciparum isolates of Malaysia and Thailand were clustered in the same group for all the allelic families. Population structure of P. falciparum isolates in Malaysia and Thailand exhibit extensive genetic polymorphism but showed high similarities as well as comparable MOI.
Collapse
Affiliation(s)
- X T Goh
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - K H Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - I Vythilingam
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - P C Lee
- Faculty of Natural Resources, University Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia
| | - T C Tan
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - N J Yap
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - H C Chai
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - V Nissapatorn
- Research Excellence Center for Innovation and Health Products (RECIHP) and School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand
| | - Y A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
49
|
Arumugam B, Palanisamy UD, Chua KH, Kuppusamy UR. Protective effect of myricetin derivatives from Syzygium malaccense against hydrogen peroxide-induced stress in ARPE-19 cells. Mol Vis 2019; 25:47-59. [PMID: 30820141 PMCID: PMC6379087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 02/05/2019] [Indexed: 12/03/2022] Open
Abstract
PURPOSE Oxidative stress is implicated in the etiology of diabetes and its debilitating complications, such as diabetic retinopathy (DR). Various flavonoids have been reported to be useful in reducing DR progression. Myricetin derivatives (F2) isolated from leaf extract of Syzygium malaccense have the potential to serve as functional food as reported previously. The present study was performed with the aim of determining the antioxidant potential and protective effect of myricetin derivatives (F2) isolated from leaf extract of S. malaccense against glucose oxidase (GO)-induced hydrogen peroxide (H2O2) production that causes oxidative stress in ARPE-19 (RPE) cells. METHODS Antioxidant properties were assessed through various radical (DPPH, ABTS, and nitric oxide) scavenging assays and determination of total phenolic content and ferric reducing antioxidant power level. ARPE-19 cells were preincubated with samples before the addition of GO (to generate H2O2). Cell viability, change in intracellular reactive oxygen species (ROS), H2O2 levels in cell culture supernatant, and gene expression were assessed. RESULTS F2 showed higher antioxidant levels than the extract when assessed for radical scavenging activities and ferric reducing antioxidant power. F2 protected the ARPE-19 cells against GO-H2O2-induced oxidative stress by reducing the production of H2O2 and intracellular reactive oxygen species. This was achieved by the activation of nuclear factor erythroid 2-related factor 2 (Nrf2/NFE2L2) and superoxide dismutase (SOD2), as well as downregulation of nitric oxide producer (NOS2) at the transcriptional level. CONCLUSIONS The results showed that myricetin derivatives from S. malaccense have the capacity to exert considerable exogenous antioxidant activities and stimulate endogenous antioxidant activities. Therefore, these derivatives have excellent potential to be developed as therapeutic agents for managing DR.
Collapse
Affiliation(s)
- Bavani Arumugam
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Uma Devi Palanisamy
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Umah Rani Kuppusamy
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
50
|
Liew SM, Rajasekaram G, Puthucheary SA, Chua KH. Antimicrobial susceptibility and virulence genes of clinical and environmental isolates of Pseudomonas aeruginosa. PeerJ 2019; 7:e6217. [PMID: 30697478 PMCID: PMC6346980 DOI: 10.7717/peerj.6217] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 12/05/2018] [Indexed: 01/03/2023] Open
Abstract
Background Pseudomonas aeruginosa is ubiquitous, has intrinsic antibiotic resistance mechanisms, and is associated with serious hospital-associated infections. It has evolved from being a burn wound infection into a major nosocomial threat. In this study, we compared and correlated the antimicrobial resistance, virulence traits and clonal relatedness between clinical and fresh water environmental isolates of P. aeruginosa. Methods 219 P. aeruginosa isolates were studied: (a) 105 clinical isolates from 1977 to 1985 (n = 52) and 2015 (n = 53), and (b) 114 environmental isolates from different fresh water sources. All isolates were subjected to ERIC-PCR typing, antimicrobial susceptibility testing and virulence factor genes screening. Results Clinical and environmental isolates of P. aeruginosa were genetically heterogenous, with only four clinical isolates showing 100% identical ERIC-PCR patterns to seven environmental isolates. Most of the clinical and environmental isolates were sensitive to almost all of the antipseudomonal drugs, except for ticarcillin/clavulanic acid. Increased resistant isolates was seen in 2015 compared to that of the archived isolates; four MDR strains were detected and all were retrieved in 2015. All clinical isolates retrieved from 1977 to 1985 were susceptible to ceftazidime and ciprofloxacin; but in comparison, the clinical isolates recovered in 2015 exhibited 9.4% resistance to ceftazidime and 5.7% to ciprofloxacin; a rise in resistance to imipenem (3.8% to 7.5%), piperacillin (9.6% to 11.3%) and amikacin (1.9% to 5.7%) and a slight drop in resistance rates to piperacillin/tazobactam (7.7% to 7.5%), ticarcillin/clavulanic acid (19.2% to 18.9%), meropenem (15.4% to 7.5%), doripenem (11.5% to 7.5%), gentamicin (7.7% to 7.5%) and netilmicin (7.7% to 7.5%). Environmental isolates were resistant to piperacillin/tazobactam (1.8%), ciprofloxacin (1.8%), piperacillin (4.4%) and carbapenems (doripenem 11.4%, meropenem 8.8% and imipenem 2.6%). Both clinical and environmental isolates showed high prevalence of virulence factor genes, but none were detected in 10 (9.5%) clinical and 18 (15.8%) environmental isolates. The exoT gene was not detected in any of the clinical isolates. Resistance to carbapenems (meropenem, doripenem and imipenem), β-lactamase inhibitors (ticarcillin/clavulanic acid and piperacillin/tazobactam), piperacillin, ceftazidime and ciprofloxacin was observed in some of the isolates without virulence factor genes. Five virulence-negative isolates were susceptible to all of the antimicrobials. Only one MDR strain harbored none of the virulence factor genes. Conclusion Over a period of 30 years, a rise in antipseudomonal drug resistance particularly to ceftazidime and ciprofloxacin was observed in two hospitals in Malaysia. The occurrence of resistant environmental isolates from densely populated areas is relevant and gives rise to collective anxiety to the community at large.
Collapse
Affiliation(s)
- Siew Mun Liew
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | | | - Sd Ampalam Puthucheary
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|