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Fulltext Two brothers in a Malaysian family with X-linked lymphoproliferative disease--a case report

Hany A, Thong MK, Lin HP

Singapore Med J, 1996 Jun;37(3):325-7.
PMID: 8942243

We report the occurrence of X-linked lymphoproliferative disease (XLP) in two brothers in a Malaysian family. In this disorder, a primary Epstein-Barr virus (EBV) infection is followed by an abnormal proliferation of transformed B-cells that cannot be controlled by suppressor T-cells, leading to the development of deranged immune function. This results in fatal infectious mononucleosis, acquired hypogammaglobulinaemia, virus-infected haemophagocytic syndrome and non-Hodgkin's lymphoma. The diagnosis should be considered when there is a family history of any male having a fulminant course of infectious mononucleosis, an otherwise benign disease. Early diagnosis is important as bone marrow transplantation is the only curative option in this disorder.

Matched MeSH terms: Lymphoproliferative Disorders/genetics*
Fulltext Turner syndrome diagnosed in northeastern Malaysia

Kannan TP, Azman BZ, Ahmad Tarmizi AB, Suhaida MA, Siti Mariam I, Ravindran A, et al.

Singapore Med J, 2008 May;49(5):400-4.
PMID: 18465051

Turner syndrome affects about one in 2,000 live-born females, and the wide range of somatic features indicates that a number of different X-located genes are responsible for the complete phenotype. This retrospective study highlights the Turner syndrome cases confirmed through cytogenetic analysis at the Human Genome Centre of Universiti Sains Malaysia, from 2001 to 2006.

Matched MeSH terms: Turner Syndrome/genetics
Fulltext Two cases of isochromosome 18q syndrome

Pal S, Siti MI, Ankathil R, Zilfalil BA

Singapore Med J, 2007 May;48(5):e146-50.
PMID: 17453088

Patients with isochromosome 18q, a rare cytogenetic abnormality, also reported as Edwards syndrome, is the second most common autosomal trisomy. However, the phenotypic features and survival of these patients are not uniform and depend upon the portion of chromosomes getting duplicated or deleted. The survival of these children may be longer, hence a good cytogenetic diagnosis is a must. Morphological characteristics of isochromosome 18q are not yet fully delineated because of the rarity of the cases and as most cases are aborted medically or terminate spontaneously. We report two cases of isochromosome 18q, one male aged two years old and the other a male aged eight months old, and review the literature on this rare syndrome.

Matched MeSH terms: Abnormalities, Multiple/genetics
Fulltext R plasmid-borne transferable multiple antibiotic resistance in a clinical isolate of Proteus sp in Peninsular Malaysia

Koh CL, Tay SH

Singapore Med J, 1984 Oct;25(5):300-3.
PMID: 6523137

A clinical isolate of Proteus sp., resistant to ampicillin, carbenicillin, cephaloridine, chloramphenicol, cotrimoxazole, gentamicin,
kanamycin and tetracycline, was examined for the presence of conjugative R plasmids. Results from conjugation, agarose gel
electrophoresis and transformation experiments showed that it harboured a large self-transmissible R plasmid which coded for all
the resistance traits.

Matched MeSH terms: Proteus/genetics*
Fulltext The oncolytic activity of Newcastle disease virus in clear cell renal carcinoma cells in normoxic and hypoxic conditions: the interplay between von Hippel-Lindau and interferon-β signaling

Ch'ng WC, Stanbridge EJ, Yusoff K, Shafee N

J Interferon Cytokine Res, 2013 Jul;33(7):346-54.
PMID: 23506478 DOI: 10.1089/jir.2012.0095

Viral-mediated oncolysis is a promising cancer therapeutic approach offering an increased efficacy with less toxicity than the current therapies. The complexity of solid tumor microenvironments includes regions of hypoxia. In these regions, the transcription factor, hypoxia inducible factor (HIF), is active and regulates expression of many genes that contribute to aggressive malignancy, radio-, and chemo-resistance. To investigate the oncolytic efficacy of a highly virulent (velogenic) Newcastle disease virus (NDV) in the presence or absence of HIF-2α, renal cell carcinoma (RCC) cell lines with defective or reconstituted wild-type (wt) von Hippel-Lindau (VHL) activity were used. We show that these RCC cells responded to NDV by producing only interferon (IFN)-β, but not IFN-α, and are associated with increased STAT1 phosphorylation. Restoration of wt VHL expression enhanced NDV-induced IFN-β production, leading to prolonged STAT1 phosphorylation and increased cell death. Hypoxia augmented NDV oncolytic activity regardless of the cells' HIF-2α levels. These results highlight the potential of oncolytic NDV as a potent therapeutic agent in the killing of hypoxic cancer cells.

Matched MeSH terms: Phosphorylation/genetics; Signal Transduction/genetics; Gene Expression Regulation, Neoplastic/genetics; Apoptosis/genetics; Transgenes/genetics; Basic Helix-Loop-Helix Transcription Factors/genetics; Von Hippel-Lindau Tumor Suppressor Protein/genetics
Development of novel kinetic model based on microbiome and biochar for in-situ remediation of total petroleum hydrocarbons (TPHs) contaminated soil

Saeed M, Ilyas N, Bibi F, Shabir S, Jayachandran K, Sayyed RZ, et al.

Chemosphere, 2023 May;324:138311.
PMID: 36878368 DOI: 10.1016/j.chemosphere.2023.138311

A novel kinetic model has been developed to explain the degradation of total petroleum hydrocarbons. Microbiome engineered biochar amendment may result in a synergistic impact on degradation of total petroleum hydrocarbons (TPHs). Therefore, the present study analyzed the potential of hydrocarbon-degrading bacteria A designated as Aeromonas hydrophila YL17 and B as Shewanella putrefaciens Pdp11 morphological characterized as rod shaped, anaerobic and gram-negative immobilized on biochar, and the degradation efficiency was measured by gravimetric analysis and gas chromatography-mass spectrometry (GC-MS). Whole genome sequencing of both strains revealed the existence of genes responsible for hydrocarbon degradation. In 60 days remediation setup, the treatment consisting of immobilization of both strains on biochar proved more efficient with less half-life and better biodegradation potentials compared to biochar without strains for decreasing the content of TPHs and n-alkanes (C12-C18). Enzymatic content and microbiological respiration showed that biochar acted as a soil fertilizer and carbon reservoir and enhanced microbial activities. The removal efficiency of hydrocarbons was found to be a maximum of 67% in soil samples treated with biochar immobilized with both strains (A + B), followed by biochar immobilized with strain B 34%, biochar immobilized with strain A 29% and with biochar 24%, respectively. A 39%, 36%, and 41% increase was observed in fluorescein diacetate (FDA) hydrolysis, polyphenol oxidase and dehydrogenase activities in immobilized biochar with both strains as compared to control and individual treatment of biochar and strains. An increase of 35% was observed in the respiration rate with the immobilization of both strains on biochar. While a maximum colony forming unit (CFU/g) was found 9.25 with immobilization of both strains on biochar at 40 days of remediation. The degradation efficiency was due to synergistic effect of both biochar and bacteria based amendment on the soil enzymatic activity and microbial respiration.

Matched MeSH terms: Bacteria/genetics
Soluble dietary fiber from Prunus persica dregs alleviates gut microbiota dysfunction through lead excretion

Yao M, Guo X, Shao X, Wei Y, Zhang X, Wang H, et al.

Food Chem Toxicol, 2023 May;175:113725.
PMID: 36925041 DOI: 10.1016/j.fct.2023.113725

Lead (Pb) can pollute the environment and food through air, water and other means, resulting in human exposure to lead pollution, and there is no threshold level of lead toxicity, even small doses of lead will have a range of harmful effects in humans. This study demonstrates for the first time that dietary addition of soluble dietary fiber (SDF) from Prunus persica dregs reduces lead bioaccumulation in mice, and eliminates lead through feces. Compared with lead-exposed mice, SDF supplementation effectively prevented lead-induced changes in colon tissue, and increased expression of tight junction proteins (ZO-1 and occludin). We analyzed the effects of SDF on gut microbiota and metabolites by a combination of 16S rRNA high-throughput sequencing and untargeted metabolomics. The results showed that SDF altered lead-induced perturbations in the layout and structure of the gut microbiota, including increased Desulfovibrio and Alistipes abundance and decreased Bacteroidetes abundance. Meanwhile, we also provide evidence that SDF supplementation alters the levels of amino acids, bile acids, and lipids in the gut, and that these metabolites are closely associated with microbiota with good lead binding capacity. Therefore, we speculate that SDF has the potential to provide a protective effect against intestinal damage by promoting lead excretion.

Matched MeSH terms: RNA, Ribosomal, 16S/genetics
Fulltext A cryptic species of the Tylonycteris pachypus complex (Chiroptera: Vespertilionidae) and its population genetic structure in southern China and nearby regions

Huang C, Yu W, Xu Z, Qiu Y, Chen M, Qiu B, et al.

Int J Biol Sci, 2014;10(2):200-11.
PMID: 24550688 DOI: 10.7150/ijbs.7301

Three distinct bamboo bat species (Tylonycteris) are known to inhabit tropical and subtropical areas of Asia, i.e., T. pachypus, T. robustula, and T. pygmaeus. This study performed karyotypic examinations of 4 specimens from southern Chinese T. p. fulvidus populations and one specimen from Thai T. p. fulvidus population, which detected distinct karyotypes (2n=30) compared with previous karyotypic descriptions of T. p. pachypus (2n=46) and T. robustula (2n=32) from Malaysia. This finding suggested a cryptic Tylonycteris species within T. pachypus complex in China and Thailand. Morphometric studies indicated the difficulty in distinguishing the cryptic species and T. p. pachypus from Indonesia apart from the external measurements, which might be the reason for their historical misidentification. Based on 623 bp mtDNA COI segments, a phylogeographic examination including T. pachypus individuals from China and nearby regions, i.e., Vietnam, Laos, and Cambodia, was conducted to examine the population genetic structure. Genealogical and phylogeographical results indicated that at least two diverged lineages existed in these regions (average 3.4 % of Kimura 2-parameter distances) and their population structure did not match the geographic pattern. These results suggested that at least two historical colonizations have occurred by the cryptic species. Furthermore, through integration of traditional and geometric morphological results, morphological differences on zygomatic arches, toothrows and bullae were detected between two lineages in China. Given the similarity of vegetation and climate of Guangdong and Guangxi regions, we suggested that such differences might be derived from their historical adaptation or distinct evolutionary history rather than the differences of habitats they occurred currently.

Matched MeSH terms: Chiroptera/genetics*
Fulltext NetSurfP-3.0: accurate and fast prediction of protein structural features by protein language models and deep learning

Høie MH, Kiehl EN, Petersen B, Nielsen M, Winther O, Nielsen H, et al.

Nucleic Acids Res, 2022 Jul 05;50(W1):W510-W515.
PMID: 35648435 DOI: 10.1093/nar/gkac439

Recent advances in machine learning and natural language processing have made it possible to profoundly advance our ability to accurately predict protein structures and their functions. While such improvements are significantly impacting the fields of biology and biotechnology at large, such methods have the downside of high demands in terms of computing power and runtime, hampering their applicability to large datasets. Here, we present NetSurfP-3.0, a tool for predicting solvent accessibility, secondary structure, structural disorder and backbone dihedral angles for each residue of an amino acid sequence. This NetSurfP update exploits recent advances in pre-trained protein language models to drastically improve the runtime of its predecessor by two orders of magnitude, while displaying similar prediction performance. We assessed the accuracy of NetSurfP-3.0 on several independent test datasets and found it to consistently produce state-of-the-art predictions for each of its output features, with a runtime that is up to to 600 times faster than the most commonly available methods performing the same tasks. The tool is freely available as a web server with a user-friendly interface to navigate the results, as well as a standalone downloadable package.

Matched MeSH terms: Proteins/genetics
Hexavalent molybdenum reduction to Mo-blue by Acinetobacter calcoaceticus

Shukor MY, Rahman MF, Suhaili Z, Shamaan NA, Syed MA

Folia Microbiol (Praha), 2010 Mar;55(2):137-43.
PMID: 20490756 DOI: 10.1007/s12223-010-0021-x

A local molybdenum-reducing bacterium was isolated and tentatively identified as Acinetobacter calcoaceticus strain Dr.Y12 based on carbon utilization profiles using Biolog GN plates and 16S rDNA comparative analysis. Molybdate reduction was optimized under conditions of low dissolved oxygen (37 degrees C and pH 6.5). Of the electron donors tested, glucose, fructose, maltose and sucrose supported molybdate reduction after 1 d of incubation, glucose and fructose supporting the highest Mo-blue production. Optimum Mo-blue production was reached at 20 mmol/L molybdate and 5 mmol/L phosphate; increasing the phosphate concentrations inhibited the production. An increase in an overall absorption profiles, especially at peak maximum at 865 nm and the shoulder at 700 nm, was observed in direct correlation with the increased in Mo-blue amounts. Metal ions, such as chromium, cadmium, copper, mercury and lead (2 mmol/L final concentration) caused approximately 88, 53, 80, 100, and 20 % inhibition, respectively. Respiratory inhibitors, such as antimycin A, rotenone, sodium azide and cyanide showed in this bacterium no inhibition of the Mo-blue production, suggesting that the electron transport system is not a site of molybdate reduction.

Matched MeSH terms: Acinetobacter calcoaceticus/genetics
Fulltext Genome analysis of a thermophilic exopolysaccharide-producing bacterium - Geobacillus sp. WSUCF1

Wang J, Goh KM, Salem DR, Sani RK

Sci Rep, 2019 02 07;9(1):1608.
PMID: 30733471 DOI: 10.1038/s41598-018-36983-z

Geobacillus sp. WSUCF1 is a Gram-positive, spore-forming, aerobic and thermophilic bacterium, isolated from a soil sample obtained from a compost facility. Strain WSUCF1 demonstrated EPS producing capability using different sugars as the carbon source. The whole-genome analysis of WSUCF1 was performed to disclose the essential genes correlated with nucleotide sugar precursor biosynthesis, assembly of monosaccharide units, export of the polysaccharide chain, and regulation of EPS production. Both the biosynthesis pathway and export mechanism of EPS were proposed based on functional annotation. Additionally, the genome description of strain WSUCF1 suggests sophisticated systems for its adaptation under thermophilic conditions. The presence of genes associated with CRISPR-Cas system, quorum quenching lactonase, polyketide synthesis and arsenic resistance makes this strain a potential candidate for various applications in biotechnology and biomedicine. The present study indicates that strain WSUCF1 has promise as a thermophilic EPS producer for a broad range of industrial applications. To the best of our knowledge, this is the first report on genome analysis of a thermophilic Geobacillus species focusing on its EPS biosynthesis and transportation, which will likely pave the way for both enhanced yield and tailor-made EPS production by thermophilic bacteria.

Matched MeSH terms: Geobacillus/genetics*
Fulltext Quantitative proteomics analysis of permethrin and temephos-resistant Ae. aegypti revealed diverse differentially expressed proteins associated with insecticide resistance from Penang Island, Malaysia

Shettima A, Ishak IH, Lau B, Abu Hasan H, Miswan N, Othman N

PLoS Negl Trop Dis, 2023 Sep;17(9):e0011604.
PMID: 37721966 DOI: 10.1371/journal.pntd.0011604

Synthetic insecticides are the primary vector control method used globally. However, the widespread use of insecticides is a major cause of insecticide-resistance in mosquitoes. Hence, this study aimed at elucidating permethrin and temephos-resistant protein expression profiles in Ae. aegypti using quantitative proteomics. In this study, we evaluated the susceptibility of Ae. aegypti from Penang Island dengue hotspot and non-hotspot against 0.75% permethrin and 31.25 mg/l temephos using WHO bioassay method. Protein extracts from the mosquitoes were then analysed using LC-ESI-MS/MS for protein identification and quantification via label-free quantitative proteomics (LFQ). Next, Perseus 1.6.14.0 statistical software was used to perform differential protein expression analysis using ANOVA and Student's t-test. The t-test selected proteins with≥2.0-fold change (FC) and ≥2 unique peptides for gene expression validation via qPCR. Finally, STRING software was used for functional ontology enrichment and protein-protein interactions (PPI). The WHO bioassay showed resistance with 28% and 53% mortalities in adult mosquitoes exposed to permethrin from the hotspot and non-hotspot areas. Meanwhile, the susceptibility of Ae. aegypti larvae revealed high resistance to temephos in hotspot and non-hotspot regions with 80% and 91% mortalities. The LFQ analyses revealed 501 and 557 (q-value <0.05) differentially expressed proteins in adults and larvae Ae. aegypti. The t-test showed 114 upregulated and 74 downregulated proteins in adult resistant versus laboratory strains exposed to permethrin. Meanwhile, 13 upregulated and 105 downregulated proteins were observed in larvae resistant versus laboratory strains exposed to temephos. The t-test revealed the upregulation of sodium/potassium-dependent ATPase β2 in adult permethrin resistant strain, H15 domain-containing protein, 60S ribosomal protein, and PB protein in larvae temephos resistant strain. The downregulation of troponin I, enolase phosphatase E1, glucosidase 2β was observed in adult permethrin resistant strain and tubulin β chain in larvae temephos resistant strain. Furthermore, the gene expression by qPCR revealed similar gene expression patterns in the above eight differentially expressed proteins. The PPI of differentially expressed proteins showed a p-value at <1.0 x 10-16 in permethrin and temephos resistant Ae. aegypti. Significantly enriched pathways in differentially expressed proteins revealed metabolic pathways, oxidative phosphorylation, carbon metabolism, biosynthesis of amino acids, glycolysis, and citrate cycle. In conclusion, this study has shown differentially expressed proteins and highlighted upregulated and downregulated proteins associated with insecticide resistance in Ae. aegypti. The validated differentially expressed proteins merit further investigation as a potential protein marker to monitor and predict insecticide resistance in field Ae. aegypti. The LC-MS/MS data were submitted into the MASSIVE database with identifier no: MSV000089259.

Matched MeSH terms: Insecticide Resistance/genetics
Fulltext Kelulut Honey Improves Folliculogenesis, Steroidogenic, and Aromatase Enzyme Profiles and Ovarian Histomorphology in Letrozole-Induced Polycystic Ovary Syndrome Rats

Kamal DAM, Ibrahim SF, Ugusman A, Zaid SSM, Mokhtar MH

Nutrients, 2022 Oct 18;14(20).
PMID: 36297046 DOI: 10.3390/nu14204364

Polycystic ovary syndrome (PCOS) has been linked to aberrant folliculogenesis and abnormalities in the aromatase enzyme (Cyp19a1) and the steroidogenic enzyme, 17-alpha-hydroxylase (Cyp17a1) expression. It has been demonstrated that Kelulut honey (KH) improves both female and male reproductive system anomalies in animal studies. Here, we examined the effects of isolated and combined KH, metformin, and clomiphene in improving folliculogenesis, aromatase, and steroidogenic enzyme profiles and ovarian histomorphology in letrozole-induced PCOS rats. Letrozole (1 mg/kg/day) was administered to female Sprague-Dawley (SD) rats for 21 days to induce PCOS. PCOS rats were subsequently divided into six experimental groups: untreated, treatment with metformin (500 mg/kg/day), clomiphene (2 mg/kg/day), KH (1 g/kg/day), combined KH (1 g/kg/day) and metformin (500 mg/kg/day), and combined KH (1 g/kg/day) and clomiphene (2 mg/kg/day). All treatments were given orally for 35 days. We found that KH was comparable with clomiphene and metformin in improving the expression of Cyp17a1 and Cyp19a1, apart from enhancing folliculogenesis both histologically and through the expression of folliculogenesis-related genes. Besides, the combination of KH with clomiphene was the most effective treatment in improving the ovarian histomorphology of PCOS rats. The effectiveness of KH in restoring altered folliculogenesis, steroidogenic, and aromatase enzyme profiles in PCOS warrants a future clinical trial to validate its therapeutic effect clinically.

Matched MeSH terms: Aromatase/genetics
Fulltext Germline breast cancer susceptibility genes, tumor characteristics, and survival

Ho PJ, Khng AJ, Loh HW, Ho WK, Yip CH, Mohd-Taib NA, et al.

Genome Med, 2021 Dec 02;13(1):185.
PMID: 34857041 DOI: 10.1186/s13073-021-00978-9

BACKGROUND: Mutations in certain genes are known to increase breast cancer risk. We study the relevance of rare protein-truncating variants (PTVs) that may result in loss-of-function in breast cancer susceptibility genes on tumor characteristics and survival in 8852 breast cancer patients of Asian descent.
METHODS: Gene panel sequencing was performed for 34 known or suspected breast cancer predisposition genes, of which nine genes (ATM, BRCA1, BRCA2, CHEK2, PALB2, BARD1, RAD51C, RAD51D, and TP53) were associated with breast cancer risk. Associations between PTV carriership in one or more genes and tumor characteristics were examined using multinomial logistic regression. Ten-year overall survival was estimated using Cox regression models in 6477 breast cancer patients after excluding older patients (≥75years) and stage 0 and IV disease.
RESULTS: PTV9genes carriership (n = 690) was significantly associated (p < 0.001) with more aggressive tumor characteristics including high grade (poorly vs well-differentiated, odds ratio [95% confidence interval] 3.48 [2.35-5.17], moderately vs well-differentiated 2.33 [1.56-3.49]), as well as luminal B [HER-] and triple-negative subtypes (vs luminal A 2.15 [1.58-2.92] and 2.85 [2.17-3.73], respectively), adjusted for age at diagnosis, study, and ethnicity. Associations with grade and luminal B [HER2-] subtype remained significant after excluding BRCA1/2 carriers. PTV25genes carriership (n = 289, excluding carriers of the nine genes associated with breast cancer) was not associated with tumor characteristics. However, PTV25genes carriership, but not PTV9genes carriership, was suggested to be associated with worse 10-year overall survival (hazard ratio [CI] 1.63 [1.16-2.28]).
CONCLUSIONS: PTV9genes carriership is associated with more aggressive tumors. Variants in other genes might be associated with the survival of breast cancer patients. The finding that PTV carriership is not just associated with higher breast cancer risk, but also more severe and fatal forms of the disease, suggests that genetic testing has the potential to provide additional health information and help healthy individuals make screening decisions.

Matched MeSH terms: BRCA1 Protein/genetics
Social demographics determinants for resistome and microbiome variation of a multiethnic community in Southern Malaysia

Dwiyanto J, Huët MAL, Hussain MH, Su TT, Tan JBL, Toh KY, et al.

NPJ Biofilms Microbiomes, 2023 Aug 12;9(1):55.
PMID: 37573460 DOI: 10.1038/s41522-023-00425-0

The prevalence of antibiotic-resistant bacteria in Southeast Asia is a significant concern, yet there is limited research on the gut resistome and its correlation with lifestyle and environmental factors in the region. This study aimed to profile the gut resistome of 200 individuals in Malaysia using shotgun metagenomic sequencing and investigate its association with questionnaire data comprising demographic and lifestyle variables. A total of 1038 antibiotic resistance genes from 26 classes were detected with a mean carriage rate of 1.74 ± 1.18 gene copies per cell per person. Correlation analysis identified 14 environmental factors, including hygiene habits, health parameters, and intestinal colonization, that were significantly associated with the resistome (adjusted multivariate PERMANOVA, p

Matched MeSH terms: Escherichia coli/genetics
Fulltext Exploring Cefiderocol Resistance Mechanisms in Burkholderia pseudomallei

Hall CM, Somprasong N, Hagen JP, Nottingham R, Sahl JW, Webb JR, et al.

Antimicrob Agents Chemother, 2023 Jun 15;67(6):e0017123.
PMID: 37133377 DOI: 10.1128/aac.00171-23

Cefiderocol is a siderophore cephalosporin designed mainly for treatment of infections caused by β-lactam and multidrug-resistant Gram-negative bacteria. Burkholderia pseudomallei clinical isolates are usually highly cefiderocol susceptible, with in vitro resistance found in a few isolates. Resistance in clinical B. pseudomallei isolates from Australia is caused by a hitherto uncharacterized mechanism. We show that, like in other Gram-negatives, the PiuA outer membrane receptor plays a major role in cefiderocol nonsusceptibility in isolates from Malaysia.

Matched MeSH terms: Drug Resistance, Multiple, Bacterial/genetics
Phenotypic and genotypic comparison of pathogenic group B Streptococcus isolated from human and cultured tilapia (Oreochromis species) in Malaysia

Muthanna A, Desa MNM, Alsalemi W, Liyana Abd Aziz NA, Dzaraly ND, Baharin NHZ, et al.

Comp Immunol Microbiol Infect Dis, 2023 Jun;97:101993.
PMID: 37167694 DOI: 10.1016/j.cimid.2023.101993

Group B Streptococcus (GBS) is a major cause of several infectious diseases in humans and fish. This study was conducted to compare human and fish-derived GBS in terms of their antimicrobial susceptibility, serotype, virulence and pili genes and sequence type (ST), and to determine whether there is a potential linkage of zoonotic transmission in Malaysia. GBS isolated from humans and fish had similar phenotypic characteristics and differed in virulence gene profile, antimicrobial susceptibility, serotype and sequence type. Fish GBS isolates had lower genetic diversity and higher antibiotic susceptibility than human isolates. We report a rare detection of the potentially fish-adapted ST283 in human GBS isolates. Both human and fish ST283 shared several phenotypic and genotypic features, including virulence and pilus genes and antimicrobial susceptibility, illustrating the value of monitoring GBS within the One Health scope. In this study, two human GBS ST283 isolates belonging to the variant common in fish hosts were identified, raising awareness of the zoonotic potential between the different species in Malaysia.

Matched MeSH terms: Streptococcus agalactiae/genetics
Increase in rotavirus prevalence with the emergence of genotype G9P[8] in replacement of genotype G12P[6] in Sabah, Malaysia

Amit LN, John JL, Mori D, Chin AZ, Mosiun AK, Ahmed K

Arch Virol, 2023 Jun 03;168(6):173.
PMID: 37269384 DOI: 10.1007/s00705-023-05803-9

Rotaviruses are major causative agents of acute diarrhea in children under 5 years of age in Malaysia. However, a rotavirus vaccine has not been included in the national vaccination program. To date, only two studies have been carried out in the state of Sabah, Malaysia, although children in this state are at risk of diarrheal diseases. Previous studies showed that 16%-17% of cases of diarrhea were caused by rotaviruses and that equine-like G3 rotavirus strains are predominant. Because the prevalence of rotaviruses and their genotype distribution vary over time, this study was conducted at four government healthcare facilities from September 2019 through February 2020. Our study revealed that the proportion of rotavirus diarrhea increased significantly to 37.2% (51/137) after the emergence of the G9P[8] genotype in replacement of the G12P[8] genotype. Although equine-like G3P[8] strains remain the predominant rotaviruses circulating among children, the Sabahan G9P[8] strain belonged to lineage VI and was phylogenetically related to strains from other countries. A comparison of the Sabahan G9 strains with the G9 vaccine strains used in the RotaSiil and Rotavac vaccines revealed several mismatches in neutralizing epitopes, indicating that these vaccines might not be effective in Sabahan children. However, a vaccine trial may be necessary to understand the precise effects of vaccination.

Matched MeSH terms: Antigens, Viral/genetics
The phenotypes and genotypes associated with biofilm formation among methicillin-susceptible Staphylococcus aureus (MSSA) isolates collected from a tertiary hospital in Terengganu, Malaysia

Jones SU, Chew CH, Yeo CC, Abdullah FH, Othman N, Kee BP, et al.

Int Microbiol, 2023 Nov;26(4):841-849.
PMID: 36805382 DOI: 10.1007/s10123-023-00335-3

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.

Matched MeSH terms: Staphylococcus aureus/genetics
Whole genome sequencing analysis demonstrates therapy-induced echinocandin resistance in Candida auris isolates

Spruijtenburg B, Ahmad S, Asadzadeh M, Alfouzan W, Al-Obaid I, Mokaddas E, et al.

Mycoses, 2023 Dec;66(12):1079-1086.
PMID: 37712885 DOI: 10.1111/myc.13655

Candida auris is an emerging, multidrug-resistant yeast, causing outbreaks in healthcare facilities. Echinocandins are the antifungal drugs of choice to treat candidiasis, as they cause few side effects and resistance is rarely found. Previously, immunocompromised patients from Kuwait with C. auris colonisation or infection were treated with echinocandins, and within days to months, resistance was reported in urine isolates. To determine whether the development of echinocandin resistance was due to independent introductions of resistant strains or resulted from intra-patient resistance development, whole genome sequencing (WGS) single-nucleotide polymorphism (SNP) analysis was performed on susceptible (n = 26) and echinocandin-resistant (n = 6) isolates from seven patients. WGS SNP analysis identified three distinct clusters differing 17-127 SNPs from two patients, and the remaining isolates from five patients, respectively. Sequential isolates within patients had a maximum of 11 SNP differences over a time period of 1-10 months. The majority of isolates with reduced susceptibility displayed unique FKS1 substitutions including a novel FKS1M690V substitution, and nearly all were genetically related, ranging from only three to six SNP differences compared to susceptible isolates from the same patient. Resistant isolates from three patients shared the common FKS1S639F substitution; however, WGS analysis did not suggest a common source. These findings strongly indicate that echinocandin resistance is induced during antifungal treatment. Future studies should determine whether such echinocandin-resistant strains are capable of long-term colonisation, cause subsequent breakthrough candidiasis, have a propensity to cross-infect other patients, or remain viable for longer time periods in the hospital environment.

Matched MeSH terms: Drug Resistance, Fungal/genetics

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