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Lentinula edodes (Shiitake) mushroom extract protects against hydrogen peroxide induced cytotoxicity in peripheral blood mononuclear cells

Kuppusamy UR, Chong YL, Mahmood AA, Indran M, Abdullah N, Vikineswary S

Indian J. Biochem. Biophys., 2009 Apr;46(2):161-5.
PMID: 19517993

Lentinula edodes (Berk) Pegler, commonly known as Shiitake mushroom has been used as medicinal food in Asian countries, especially in China and Japan and is believed to possess strong immunomodulatory property. In the present study, the methanolic extract of the fruit bodies of L. edodes was investigated for cytoprotective effect against H2O2-induced cytotoxicity in human peripheral blood mononuclear cells (PBMCs) by measuring the activities of xanthine oxidase (XO) and glutathione peroxidase (GPx) . H2O2 at a concentration of 5 microM caused 50% inhibition of PBMCs viability. The extract improved the PBMC viability and exerted a dose-dependent protection against H2O2-induced cytotoxicity. At 100 microg/ml of extract concentration, the cell viability increased by 60% compared with the PBMCs incubated with H2O2 alone. The extract also inhibited XO activity in PBMC, while showing moderate stimulatory effect on GPx. However, in the presence of H2O2 alone, both the enzyme activities were increased significantly. The GPx activity increased, possibly in response to the increased availability of H2O2 in the cell. When the cells were pretreated with the extract and washed (to remove the extract) prior to the addition of H2O2, the GPx and XO activities as well as the cell viability were comparable to those when incubated with the extract alone. Thus, it is suggested that one of the possible mechanisms via which L. edodes methanolic extract confers protection against H2O2-induced oxidative stress in PBMC is by inhibiting the superoxide-producing XO and increasing GPx activity which could rapidly inactivate H2O2.
Grossly delayed graft function in a living related kidney transplant recipient: a case report

Thye YL, Lim SK, Wong CM, Keng TC, Chong YB, Tan SY

Transplant Proc, 2008 Sep;40(7):2435-6.
PMID: 18790259 DOI: 10.1016/j.transproceed.2008.07.051

Delayed graft function is a potentially challenging problem especially in cadaveric kidney transplant recipients. It adversely impacts long-term graft survival. It is rarely seen in living kidney transplants. Recovery of graft function usually occurs within a month. The chances of recovery of graft function diminish with further prolongation of delayed function. In fact, recovery of graft function after 3 months has rarely been described, we report herein recovery of graft function after 132 days of nonfunction in a living related kidney transplant.
Fulltext A study on the food and nutritional status of the Armed Forces

Chong YH, Tee ES, Ng TKW, Yap SB, Mok SK

Med J Malaysia, 1982 Mar;37(1):46-51.
PMID: 7121346

The nutritional status of 158 soldiers drawn from four army camps in Selangor, Negeri Sembilan and Pahang has been assessed by biochemical procedures, nutritional anthropometry and dietary (chemical) analysis. Biochemical assessment showed that with the exception of thiamin and riboflavin nutriture, the nutritional status of the soldiers appeared generally satisfactory and seemed to have improved slightly over those examined by the Inter-Departmental Committee on Nutrition and National Defence (ICNND), USA, in 1962 by similar methods. The anthropometric assessment indicated that the present day soldiers have the same mean height as those examined in 1962. Although they appeared slightly heavier, obesity did not seem to be a problem. Chemical analysis of their diet showed that there is room for improvement in the dietary supply of vitamin A and some of the water-soluble vitamins, particularly riboflavin, thiamin and vitamin C. There was also a significant discrepancy between the nutritional content of the chemically-analysed cooked meals and those calculated from the ration scales using Food Composition Tables, suggesting a need to review the current system of food supply,
preparation and food sertnce unthin army camps in
Malaysia.
Fulltext Penicilliosis in lupus patients presenting with unresolved fever: a report of 2 cases and literature review

Chong YB, Tan LP, Robinson S, Lim SK, Ng KP, Keng TC, et al.

Trop Biomed, 2012 Jun;29(2):270-6.
PMID: 22735849 MyJurnal

Penicilliosis is a rare occurrence among non human immunodeficiency virus (HIV) infected patients. We report here two cases of Penicillium marneffei infection in patients with systemic lupus erythematosus (SLE). Both patients had a recent flare of lupus and were on immunosuppressive drugs when they presented with prolonged fever without an obvious foci of infection, unresponsive to broad-spectrum antibiotics. They were leucopaenic upon admission, with rapid deterioration during the course of the illness. Diagnosis of penicilliosis via fungal isolation from blood culture was delayed resulting in the late initiation of antifungal agents. While both patients ultimately recovered, the delay in diagnosis led to a prolonged hospital stay with increased morbidity. Clinicians should be aware of this uncommon but emerging fungal pathogen in SLE patients and maintain a high index of suspicion in diagnosing this potentially fatal but treatable disease.
Interocular optical biometry differences as predictors of postoperative cataract surgery refractive outcomes: A retrospective cohort study

Wai YZ, Ng QX, Adnan TH, Chong YY, Mohamad AS, Goh PP

Med J Malaysia, 2021 Nov;76(6):884-892.
PMID: 34806678

INTRODUCTION: Few studies have reported the impact of preoperative interocular discrepancy in optical biometry (axial length, corneal power, white-to-white, central corneal thickness) on postoperative refractive outcomes. This study aims to investigate any predictive value of preoperative optical biometry differences between eyes on postoperative refractive outcomes.
MATERIALS AND METHODS: A retrospective cohort study of patients who have undergone optical biometry measurement before unilateral phacoemulsification in the Queen Elizabeth Hospital, Sabah, Malaysia from 2018 to 2020. Biometry data of interest includes axial length (AL), keratometry(K), white-to-white (WTW) and central corneal thickness (CCT). The postoperative outcomes of interest were the patient's preoperative refractive target, postoperative best-corrected visual acuity (BCVA), postoperative refractive outcomes, and optical biometry prediction error.
RESULTS: The interocular biometry discrepancies which were associated with higher odds of prediction error >0.5D from the refractive target were Interocular Corneal Power Difference (IKD)-average≥0.8 D (Odds Ratio, OR=1.97; 95% Confidence Intervals, 95%CI: 1.06, 3.67) and Interocular WTW Difference ≥1.5 mm (OR=2.77; 95%CI: 1.11, 6.92). In cases with prediction error >1.0D, the measurements were Interocular AL Difference ≥0.4 mm (OR=2.99; 95%CI: 1.11, 8.06), IKD flat≥0.4D (OR=2.76; 95%CI: 1.31, 5.82) and Interocular CCT Difference ≥15μm (OR=3.53; 95%CI: 1.29, 9.64).
CONCLUSION: Interocular axial length difference ≥0.4mm and interocular central corneal thickness difference ≥15μm are associated with refractive error >1.0D from the pre-operative target. Interocular average corneal power difference ≥0.8D and interocular white-to-white difference ≥1.5mm have higher odds of refractive drift >0.5D from the refractive aim. The above cutoff values help clinicians to identify which patients have a higher risk of refractive shift post-cataract surgery and counsel the patient before cataract operation.
Fulltext Hemorrhage in a Fetal Ovarian Cyst

Hassan R, Chong YC, Khairun Nisa M, Yew CG, Tan PG, Mazlin J

J Neonatal Surg, 2017 Apr 15;6(2):49.
PMID: 28770146 DOI: 10.21699/jns.v6i2.505
Fulltext Klebsiella pneumoniae respiratory isolates from 2000 to 2004 in a Malaysian hospital: characteristics and relation to hospital antibiotics consumption

Loh LC, Chin HK, Chong YY, Jeyaratnam A, Raman S, Vijayasingham P, et al.

Singapore Med J, 2007 Sep;48(9):813-8.
PMID: 17728961

Klebsiella pneumoniae ranks high as a cause of community-acquired pneumonia in hospitalised patients in Malaysia.
The synthetic curcuminoid BHMC restores endotoxin-stimulated HUVEC dysfunction:Specific disruption on enzymatic activity of p38 MAPK

Tham CL, Hazeera Harith H, Wai Lam K, Joong Chong Y, Singh Cheema M, Roslan Sulaiman M, et al.

Eur J Pharmacol, 2015 Feb 15;749:1-11.
PMID: 25560198 DOI: 10.1016/j.ejphar.2014.12.015

2,6-bis-(4-hydroxyl-3-methoxybenzylidine)cyclohexanone (BHMC) has been proven to selectively inhibit the synthesis of proinflammatory mediators in lipopolysaccharide-induced U937 monocytes through specific interruption of p38 Mitogen-Activated Protein Kinase enzymatic activity and improves the survival rate in a murine lethal sepsis model. The present study addressed the effects of BHMC upon lipopolysaccharide-induced endothelial dysfunction in human umbilical vein endothelial cells to determine the underlying mechanisms. The cytotoxicity effect of BHMC on HUVEC were determined by MTT assay. The effects of BHMC on endothelial dysfunction induced by lipopolysaccharide such as endothelial hyperpermeability, monocyte-endothelial adhesion, transendothelial migration, up-regulation of adhesion molecules and chemokines were evaluated. The effects of BHMC at transcriptional and post-translational levels were determined by Reverse Transcriptase-Polymerase Chain Reaction and Western Blots. The mode of action of BHMC was dissected by looking into the activation of Nuclear Factor-kappa B and Mitogen-Activated Protein Kinases. BHMC concentration-dependently reduced endothelial hyperpermeability, leukocyte-endothelial cell adhesion and monocyte transendothelial migration through inhibition of the protein expression of adhesion molecules (Intercellular Adhesion Molecule-1 and Vascular Cell Adhesion Molecule-1) and secretion of chemokines (Monocyte Chemotactic Protein-1) at the transcriptional level. BHMC restored endothelial dysfunction via selective inhibition of p38 Mitogen-Activated Protein Kinase enzymatic activity which indirectly prevents the activation of Nuclear Factor-kappaB and Activator Protein-1 transcription factors. These findings further support earlier observations on the inhibition of BHMC on inflammatory events through specific disruption of p38 Mitogen-Activated Protein Kinase enzymatic activity and provide new insights into the inhibitory effects of BHMC on lipopolysaccharide-induced endothelial dysfunction.
Associations between ethnicity, body composition, and bone mineral density in a Southeast Asian population

Yang PL, Lu Y, Khoo CM, Leow MK, Khoo EY, Teo A, et al.

J Clin Endocrinol Metab, 2013 Nov;98(11):4516-23.
PMID: 24037892 DOI: 10.1210/jc.2013-2454

Chinese men in Singapore have a higher incidence of hip fractures than Malay and Indian men. We investigated whether there were corresponding ethnic differences in peak bone mineral density (BMD) in young men and whether differences in body composition influenced peak BMD.
Fulltext The evolutionary history of hepaciviruses

Li YQ, Ghafari M, Holbrook AJ, Boonen I, Amor N, Catalano S, et al.

bioRxiv, 2023 Jun 30.
PMID: 37425679 DOI: 10.1101/2023.06.30.547218

In the search for natural reservoirs of hepatitis C virus (HCV), a broad diversity of non-human viruses within the Hepacivirus genus has been uncovered. However, the evolutionary dynamics that shaped the diversity and timescale of hepaciviruses evolution remain elusive. To gain further insights into the origins and evolution of this genus, we screened a large dataset of wild mammal samples (n = 1,672) from Africa and Asia, and generated 34 full-length hepacivirus genomes. Phylogenetic analysis of these data together with publicly available genomes emphasizes the importance of rodents as hepacivirus hosts and we identify 13 rodent species and 3 rodent genera (in Cricetidae and Muridae families) as novel hosts of hepaciviruses. Through co-phylogenetic analyses, we demonstrate that hepacivirus diversity has been affected by cross-species transmission events against the backdrop of detectable signal of virus-host co-divergence in the deep evolutionary history. Using a Bayesian phylogenetic multidimensional scaling approach, we explore the extent to which host relatedness and geographic distances have structured present-day hepacivirus diversity. Our results provide evidence for a substantial structuring of mammalian hepacivirus diversity by host as well as geography, with a somewhat more irregular diffusion process in geographic space. Finally, using a mechanistic model that accounts for substitution saturation, we provide the first formal estimates of the timescale of hepacivirus evolution and estimate the origin of the genus to be about 22 million years ago. Our results offer a comprehensive overview of the micro- and macroevolutionary processes that have shaped hepacivirus diversity and enhance our understanding of the long-term evolution of the Hepacivirus genus.