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  1. Fulltext A Transcriptome-Wide Association Study Identifies Novel Candidate Susceptibility Genes for Pancreatic Cancer
    Zhong J, Jermusyk A, Wu L, Hoskins JW, Collins I, Mocci E, et al.
    J Natl Cancer Inst, 2020 Oct 01;112(10):1003-1012.
    PMID: 31917448 DOI: 10.1093/jnci/djz246
    BACKGROUND: Although 20 pancreatic cancer susceptibility loci have been identified through genome-wide association studies in individuals of European ancestry, much of its heritability remains unexplained and the genes responsible largely unknown.

    METHODS: To discover novel pancreatic cancer risk loci and possible causal genes, we performed a pancreatic cancer transcriptome-wide association study in Europeans using three approaches: FUSION, MetaXcan, and Summary-MulTiXcan. We integrated genome-wide association studies summary statistics from 9040 pancreatic cancer cases and 12 496 controls, with gene expression prediction models built using transcriptome data from histologically normal pancreatic tissue samples (NCI Laboratory of Translational Genomics [n = 95] and Genotype-Tissue Expression v7 [n = 174] datasets) and data from 48 different tissues (Genotype-Tissue Expression v7, n = 74-421 samples).

    RESULTS: We identified 25 genes whose genetically predicted expression was statistically significantly associated with pancreatic cancer risk (false discovery rate < .05), including 14 candidate genes at 11 novel loci (1p36.12: CELA3B; 9q31.1: SMC2, SMC2-AS1; 10q23.31: RP11-80H5.9; 12q13.13: SMUG1; 14q32.33: BTBD6; 15q23: HEXA; 15q26.1: RCCD1; 17q12: PNMT, CDK12, PGAP3; 17q22: SUPT4H1; 18q11.22: RP11-888D10.3; and 19p13.11: PGPEP1) and 11 at six known risk loci (5p15.33: TERT, CLPTM1L, ZDHHC11B; 7p14.1: INHBA; 9q34.2: ABO; 13q12.2: PDX1; 13q22.1: KLF5; and 16q23.1: WDR59, CFDP1, BCAR1, TMEM170A). The association for 12 of these genes (CELA3B, SMC2, and PNMT at novel risk loci and TERT, CLPTM1L, INHBA, ABO, PDX1, KLF5, WDR59, CFDP1, and BCAR1 at known loci) remained statistically significant after Bonferroni correction.

    CONCLUSIONS: By integrating gene expression and genotype data, we identified novel pancreatic cancer risk loci and candidate functional genes that warrant further investigation.

  2. Engineering ellipsoidal cap-like hydrogel particles as building blocks or sacrificial templates for three-dimensional cell culture
    Zhang W, Huang G, Ng K, Ji Y, Gao B, Huang L, et al.
    Biomater Sci, 2018 Mar 07.
    PMID: 29511758 DOI: 10.1039/c7bm01186e
    Hydrogel particles that can be engineered to compartmentally culture cells in a three-dimensional (3D) and high-throughput manner have attracted increasing interest in the biomedical area. However, the ability to generate hydrogel particles with specially designed structures and their potential biomedical applications need to be further explored. This work introduces a method for fabricating hydrogel particles in an ellipsoidal cap-like shape (i.e., ellipsoidal cap-like hydrogel particles) by employing an open-pore anodic aluminum oxide membrane. Hydrogel particles of different sizes are fabricated. The ability to produce ellipsoidal cap-like magnetic hydrogel particles with controlled distribution of magnetic nanoparticles is demonstrated. Encapsulated cells show high viability, indicating the potential for using these hydrogel particles as structure- and remote-controllable building blocks for tissue engineering application. Moreover, the hydrogel particles are also used as sacrificial templates for fabricating ellipsoidal cap-like concave wells, which are further applied for producing size controllable cell aggregates. The results are beneficial for the development of hydrogel particles and their applications in 3D cell culture.
  3. Comparison of planned and measured rectal dose in-vivo during high dose rate Cobalt-60 brachytherapy of cervical cancer
    Zaman ZK, Ung NM, Malik RA, Ho GF, Phua VC, Jamalludin Z, et al.
    Phys Med, 2014 Dec;30(8):980-4.
    PMID: 25086486 DOI: 10.1016/j.ejmp.2014.07.002
    Cobalt-60 (Co-60) is a relatively new source for the application of high-dose rate (HDR) brachytherapy. Radiation dose to the rectum is often a limiting factor in achieving the full prescribed dose to the target during brachytherapy of cervical cancer. The aim of this study was to measure radiation doses to the rectum in-vivo during HDR Co-60 brachytherapy. A total of eleven HDR brachytherapy treatments of cervical cancer were recruited in this study. A series of diodes incorporated in a rectal probe was inserted into the patient's rectum during each brachytherapy procedure. Real-time measured rectal doses were compared to calculated doses by the treatment planning system (TPS). The differences between calculated and measured dose ranged from 8.5% to 41.2%. This corresponds to absolute dose differences ranging from 0.3 Gy to 1.5 Gy. A linear relationship was observed between calculated and measured doses with linear regression R(2) value of 0.88, indicating close association between the measured and calculated doses. In general, absorbed doses for the rectum as calculated by TPS were observed to be higher than the doses measured using the diode probe. In-vivo dosimetry is an important quality assurance method for HDR brachytherapy of cervical cancer. It provides information that can contribute to the reduction of errors and discrepancies in dose delivery. Our study has shown that in-vivo dosimetry is feasible and can be performed to estimate the dose to the rectum during HDR brachytherapy using Co-60.
  4. Fulltext Genome-Wide Association Study Data Reveal Genetic Susceptibility to Chronic Inflammatory Intestinal Diseases and Pancreatic Ductal Adenocarcinoma Risk
    Yuan F, Hung RJ, Walsh N, Zhang H, Platz EA, Wheeler W, et al.
    Cancer Res, 2020 Sep 15;80(18):4004-4013.
    PMID: 32641412 DOI: 10.1158/0008-5472.CAN-20-0447
    Registry-based epidemiologic studies suggest associations between chronic inflammatory intestinal diseases and pancreatic ductal adenocarcinoma (PDAC). As genetic susceptibility contributes to a large proportion of chronic inflammatory intestinal diseases, we hypothesize that the genomic regions surrounding established genome-wide associated variants for these chronic inflammatory diseases are associated with PDAC. We examined the association between PDAC and genomic regions (±500 kb) surrounding established common susceptibility variants for ulcerative colitis, Crohn's disease, inflammatory bowel disease, celiac disease, chronic pancreatitis, and primary sclerosing cholangitis. We analyzed summary statistics from genome-wide association studies data for 8,384 cases and 11,955 controls of European descent from two large consortium studies using the summary data-based adaptive rank truncated product method to examine the overall association of combined genomic regions for each inflammatory disease group. Combined genomic susceptibility regions for ulcerative colitis, Crohn disease, inflammatory bowel disease, and chronic pancreatitis were associated with PDAC at P values < 0.05 (0.0040, 0.0057, 0.011, and 3.4 × 10-6, respectively). After excluding the 20 PDAC susceptibility regions (±500 kb) previously identified by GWAS, the genomic regions for ulcerative colitis, Crohn disease, and inflammatory bowel disease remained associated with PDAC (P = 0.0029, 0.0057, and 0.0098, respectively). Genomic regions for celiac disease (P = 0.22) and primary sclerosing cholangitis (P = 0.078) were not associated with PDAC. Our results support the hypothesis that genomic regions surrounding variants associated with inflammatory intestinal diseases, particularly, ulcerative colitis, Crohn disease, inflammatory bowel disease, and chronic pancreatitis are associated with PDAC. SIGNIFICANCE: The joint effects of common variants in genomic regions containing susceptibility loci for inflammatory bowel disease and chronic pancreatitis are associated with PDAC and may provide insights to understanding pancreatic cancer etiology.
  5. Predictors of axillary lymph node metastases in breast cancer: is there a role for minimal axillary surgery?
    Yip CH, Taib NA, Tan GH, Ng KL, Yoong BK, Choo WY
    World J Surg, 2009 Jan;33(1):54-7.
    PMID: 18958521 DOI: 10.1007/s00268-008-9782-7
    Axillary nodal status is one of the most important prognostic factors in breast cancer. In the present study we used it to determine the predictors of axillary lymph node metastases in breast cancer and to determine if there is a group of patients in whom minimal axillary surgery is indicated.
  6. Fulltext Risk-adjusted surgical audit with the POSSUM scoring system in a developing country. Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity
    Yii MK, Ng KJ
    Br J Surg, 2002 Jan;89(1):110-3.
    PMID: 11851674
    BACKGROUND: The Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) is an objective and appropriate scoring system for risk-adjusted comparative general surgical audit. This score was devised in the UK and has been used widely, but application of POSSUM to centres outside the UK has been limited, especially in developing countries. This prospective study validated its application in a surgical practice with a different population and level of resources.
    METHODS: All general surgical patients who were operated on under regional or general anaesthesia as inpatients over a 4-month period at Sarawak General Hospital in 1999 were entered into the study. All data (12 physiological and six operative factors) were analysed for mortality only with the POSSUM equation and the modified Portsmouth POSSUM (P-POSSUM) equation. Comparisons were made between predicted and observed mortality rates according to four groups of risk: 0-4, 5-14, 15-49 and 50 per cent or more using the 'linear' method of analysis.
    RESULTS: There were 605 patients who satisfied the criteria for the study. Some 56.7 per cent of patients were in the lowest risk group. The POSSUM predictor equation significantly overestimated the mortality in this group, by a factor of 9.3. The overall observed mortality rate was 6.1 per cent and, again, the POSSUM predictor equation overestimated it at 10.5 per cent (P < 0.01). In contrast, the observed and predicted mortality rates for all risk groups, including the predicted overall mortality rate of 4.8 per cent, were comparable when the P-POSSUM predictor equation was used.
    CONCLUSION: The POSSUM scoring system with the modified P-POSSUM predictor equation for mortality was applicable in Malaysia, a developing country, for risk-adjusted surgical audit. This scoring system may serve as a useful comparative audit tool for surgical practice in many geographical locations.
  7. Reproducibility of neutron activated Sm-153 oral dose formulations intended for human administration
    Yeong CH, Blackshaw PE, Ng KH, Abdullah BJ, Blaauw M, Dansereau RJ, et al.
    Appl Radiat Isot, 2011 Sep;69(9):1181-4.
    PMID: 21550260 DOI: 10.1016/j.apradiso.2011.04.017
    Neutron activation of Sm-152 offers a method of radiolabeling for the in vivo study of oral dose formulations by gamma scintigraphy. Reproducibility measurements are needed to ensure the robustness of clinical studies. 204 enteric-coated guaifenesin core tablets (10mg of Sm(2)O(3)) were irradiated by thermal neutrons to achieve 1 MBq at 48 h. Administered activities were 0.86±0.03 MBq. Good reproducibility (CV=3.5%) was observed over 24 weeks ensuring that volunteer doses were within the dose reference level of 0.8 mSv.
  8. Enterovirus 71 encephalomyelitis and Japanese encephalitis can be distinguished by topographic distribution of inflammation and specific intraneuronal detection of viral antigen and RNA
    Wong KT, Ng KY, Ong KC, Ng WF, Shankar SK, Mahadevan A, et al.
    Neuropathol. Appl. Neurobiol., 2012 Aug;38(5):443-53.
    PMID: 22236252 DOI: 10.1111/j.1365-2990.2011.01247.x
    To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished.
  9. Development and evaluation of a computer expert system for the management of fetal distress
    Wong KK, Ng KH, Nah SH, Yusof K, Rajeswari K
    Asia Oceania J Obstet Gynaecol, 1994 Mar;20(1):19-23.
    PMID: 8172522
    The general lack of specialist obstetricians in a developing country such as Malaysia prompted us to develop a computer expert system for the management of fetal distress in rural hospitals. It was based on accepted production rules and implemented on a microcomputer. The clinical prototype was evaluated by 8 specialist obstetricians and 21 non-specialist doctors involved in obstetric care. The initial impression was that this type of expert system may help in diagnosis, decision-making and teaching.
  10. Intracranial aneurysms in Sarawak General Hospital over a 30-month period
    Wong JS, Ng KH, Wong SH
    J Clin Neurosci, 2004 Apr;11(3):254-8.
    PMID: 14975412
    This is a prospective study conducted from February 2000 to July 2002 in a single neurosurgeon neurosurgical service in the state of Sarawak, Malaysia. There were 66 cases of subarachnoid hemorrhage or intracranial aneurysm presenting to this hospital over the study period. Fifty cases had their aneurysms clipped. Eighty percent of our patients were operated within 48 h of presentation. Forty-four percent presented with poor WFNS grades of 4 and 5. We had a 20% operative mortality and 29% total management mortality. Twenty-nine (58%) of the operated cases had a favorable outcome with a mean follow-up of 32 weeks. Multiple aneurysms were less common. The diagnosis of aneuysmal subarachnoid hemorrhage and clipping of aneurysms have increased dramatically over the previous two and half years indicating an increased awareness of the diagnosis and treatment. This series supports the previously reported beliefs that the lower rate of aneurymal subarachnoid hemorrhage in developing countries is likely due to both underdiagnosis and undertreatment. Good results can be achieved in developing countries with early diagnosis and intensive management.
  11. CHARACTERISATION AND EVALUATION OF AL2O3:C-BASED OPTICALLY STIMULATED LUMINESCENT DOSEMETER SYSTEM FOR DIAGNOSTIC X-RAYS: PERSONAL AND IN VIVO DOSIMETRY
    Wong JHD, Bakhsh M, Cheah YY, Jong WL, Khor JS, Ng KH
    Radiat Prot Dosimetry, 2019 Dec 31;187(4):451-460.
    PMID: 31650160 DOI: 10.1093/rpd/ncz186
    This study characterises and evaluates an Al2O3:C-based optically stimulated luminescent dosemeter (OSLD) system, commercially known as the nanoDot™ dosemeter and the InLight® microStar reader, for personal and in vivo dose measurements in diagnostic radiology. The system characteristics, such as dose linearity, reader accuracy, reproducibility, batch homogeneity, energy dependence and signal stability, were explored. The suitability of the nanoDot™ dosemeters was evaluated by measuring the depth dose curve, in vivo dose measurement and image perturbation. The nanoDot™ dosemeters were observed to produce a linear dose with ±2.8% coefficient variation. Significant batch inhomogeneity (8.3%) was observed. A slight energy dependence (±6.1%) was observed between 60 and 140 kVp. The InLight® microStar reader demonstrated good accuracy and a reproducibility of ±2%. The depth dose curve measured using nanoDot™ dosemeters showed slightly lower responses than Monte Carlo simulation results. The total uncertainty for a single dose measurement using this system was 11%, but it could be reduced to 9.2% when energy dependence correction was applied.
  12. Fulltext Ectopic pregnancy: uncommon presentations and difficulty in diagnosis
    Wong CM, Ganesh R, Ng KY
    Med J Malaysia, 1999 Mar;54(1):117-9.
    PMID: 10972015
    Diagnosis of ectopic pregnancy prior to rupture is an arduous task even with the availability of many new investigative methods and imaging modalities. Above all, a high index of suspicion is necessary when dealing with women who present in early pregnancy with abdominal pain and vaginal bleeding. With the increased use of ovulation induction agents, the probability of heterotropic pregnancy should be kept in mind. The use of transvaginal ultrasonography (TVS) will help in earlier diagnosis because of its advantages over transabdominal ultrasonography (TAS).
  13. Pregnancy-induced hypertension and placenta previa: a racial and geographical perspective
    Wang JC, Hin LY, Ng KB
    Int J Gynaecol Obstet, 1999 Dec;67(3):177-8.
    PMID: 10659902
  14. Fulltext High-frequency hearing loss among mobile phone users
    Velayutham P, Govindasamy GK, Raman R, Prepageran N, Ng KH
    Indian J Otolaryngol Head Neck Surg, 2014 Jan;66(Suppl 1):169-72.
    PMID: 24533378 DOI: 10.1007/s12070-011-0406-4
    The objective of this study is to assess high frequency hearing (above 8 kHz) loss among prolonged mobile phone users is a tertiary Referral Center. Prospective single blinded study. This is the first study that used high-frequency audiometry. The wide usage of mobile phone is so profound that we were unable to find enough non-users as a control group. Therefore we compared the non-dominant ear to the dominant ear using audiometric measurements. The study was a blinded study wherein the audiologist did not know which was the dominant ear. A total of 100 subjects were studied. Of the subjects studied 53% were males and 47% females. Mean age was 27. The left ear was dominant in 63%, 22% were dominant in the right ear and 15% did not have a preference. This study showed that there is significant loss in the dominant ear compared to the non-dominant ear (P 
  15. Fulltext Does the pre-operative value of serum CA15-3 correlate with survival in breast cancer?
    Velaiutham S, Taib NA, Ng KL, Yoong BK, Yip CH
    Asian Pac J Cancer Prev, 2008 Jul-Sep;9(3):445-8.
    PMID: 18990019
    INTRODUCTION: CA15-3 is a well-known tumour marker for breast cancer. Currently it is not recommended for screening or diagnosis of breast cancer and its main application is in monitoring response to treatment in women with metastatic breast cancer. The aim of this study was to correlate serum CA15-3 at presentation with the stage of disease and overall survival in women with breast cancer in the University Malaya Medical Centre.

    METHODS: This is a retrospective study of 437 women who had CA15-3 levels determined at initial presentation of breast cancer to UMMC between Jan 1999 and Oct 2003.

    RESULTS: Of those patients who were adequately staged, CA15-3 was found to be elevated (defined as >51 U/ml) in 0% of Stage 1, 7.9% of Stage 2, 36.7% of Stage 3 and 68.6% of Stage 4 cases. In a subset of 331 patients with survival data, patients with normal CA15-3 had a 85% five year overall survival rate compared to 38% in their counterparts with elevation of the tumor marker. The level of elevation was also significantly related to survival; patients with values more than 200 U/ml exhibited only a 28% five year survival. The association of elevated CA15-3 at initial presentation with poor outcome was maintained over univariate and multivariate analyses.

    CONCLUSION: Estimation of CA15-3 at presentation of breast cancer is important as it is an independent prognostic indicator and may prompt the physician to investigate for metastases if elevated.
  16. Application of immersed MF (IMF) followed by reverse osmosis (RO) membrane for wastewater reclamation: A case study in Malaysia
    Ujang Z, Ng KS, Tg Hamzah TH, Roger P, Ismail MR, Shahabudin SM, et al.
    Water Sci Technol, 2007;56(9):103-8.
    PMID: 18025737
    A pilot scale membrane plant was constructed and monitored in Shah Alam, Malaysia for municipal wastewater reclamation for industrial application purposes. The aim of this study was to verify its suitability under the local conditions and environmental constraints for secondary wastewater reclamation. Immersed-type crossflow microfiltration (IMF) was selected as the pretreatment step before reverse osmosis filtration. Secondary wastewater after chlorine contact tank was selected as feed water. The results indicated that the membrane system is capable of producing a filtrate meeting the requirements of both WHO drinking water standards and Malaysian Effluent Standard A. With the application of an automatic backwash process, IMF performed well in hydraulic performance with low fouling rate being achieved. The investigations showed also that chemical cleaning is still needed because of some irreversible fouling by microorganisms always remains. RO treatment with IMF pretreatment process was significantly applicable for wastewater reuse purposes and promised good hydraulic performance.
  17. Prophylactic intravenous tranexamic acid and thromboembolism in non-cardiac surgery: a systematic review, meta-analysis and trial sequential analysis
    Tsan SEH, Viknaswaran NL, Cheong CC, Cheah S, Ng KT, Mong SXY, et al.
    Anaesthesia, 2023 Sep;78(9):1153-1161.
    PMID: 37314744 DOI: 10.1111/anae.16058
    Tranexamic acid is an antifibrinolytic drug that is widely used during surgery, but there are concerns about its thromboembolic effects. We aimed to investigate the effect of prophylactic intravenous tranexamic acid on thromboembolic outcomes in patients undergoing non-cardiac surgery. The MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials were searched. Randomised controlled trials comparing intravenous tranexamic acid with placebo or no treatment in patients undergoing non-cardiac surgery were included. The primary outcome was a composite of peri-operative cardiovascular thromboembolic events, defined as any deep vein thrombosis, pulmonary embolism, myocardial ischaemia/infarction or cerebral ischaemia/infarction. A total of 191 randomised controlled trials (40,621 patients) were included in the review. The primary outcome occurred in 4.5% of patients receiving intravenous tranexamic acid compared with 4.9% of patients in the control group. Our analysis showed that there was no difference between groups for composite cardiovascular thromboembolic events (risk ratio 1.02, 95%CI 0.94-1.11, p = 0.65, I2 0%, n = 37,512). This finding remained robust when sensitivity analysis was performed with continuity correction and in studies with a low risk of bias. However, in trial sequential analysis, our meta-analysis only achieved 64.6% of the required information size. There was no association between intravenous tranexamic acid and seizure rate or mortality rate within 30 days. Intravenous tranexamic acid was associated with a reduced blood transfusion rate compared with control (9.9% vs. 19.4%, risk ratio 0.46, 95%CI 0.41-0.51, p 
  18. Fulltext DietPLUS- a User-friendly '2 in 1' Food Composition Database and Calculator of Nutrient Intakes
    Tony Ng KW
    Malays J Nutr, 2010 Apr;16(1):125-30.
    PMID: 22691859 MyJurnal
    The teaching and research tool called 'DietPLUS', developed by the present author at an institution of higher learning in 2007, contains nutrient information of 840 food items in Excel format. DietPLUS functions as a '2-in-1' food composition database plus a rapid calculator of nutrient intakes, with the option of 'collapsing' the food composition face leaving only the nutrient calculator face. The macronutrients featured in the programme are energy, protein, fat, carbohydrates, dietary fibre, sugars (intrinsic + added), polyunsatuared omega-6 fatty acids (mainly linoleic acid, LA) and polyunsaturated omega-3 fatty acids [alphalinolenic acid (ALA) or eicosapentaenic acid (EPA) + docosahexaenolic acid (DHA)]. The micronutrients in the programme are vitamin A (as retinol equivalents, RE), vitamin C, thiamin (vitamin B1), riboflavin (vitamin B2), and niacin. Cholesterol content was included to complete the list of food components tabled. Food items consumed are converted into gram quantities (edible portion) and are entered in one column in the Excel programme which emphasises the simplicity and user-friendliness of the present nutrient calculator. DietPLUS instantaneously sums up the macronutrients and micronutrients consumed with each subsequent entry. Macronutrients (protein, fat, carbohydrate, sugars and dietary fibre) consumed are presented as gram quantities and a percentage of the Recommended Nutrient Intakes for Malaysia 2005. An approximate number of servings are also provided for vegetables, fruits, legumes, fish and meat, which may be useful in meal planning and nutrition/dietetic counselling.
  19. Author Reply
    Teoh WY, Ng KT
    Prehosp Disaster Med, 2020 Jun;35(3):352.
    PMID: 32264983 DOI: 10.1017/S1049023X20000436
  20. Fulltext Phytobezoar: an unusual cause of intestinal obstruction
    Teng H, Nawawi O, Ng K, Yik Y
    Biomed Imaging Interv J, 2005 Jul;1(1):e4.
    PMID: 21625276 MyJurnal DOI: 10.2349/biij.1.1.e4
    Small bowel phytobezoars are rare and almost always obstructive. There have been previously reported cases of phytobezoars in the literature, however there are few reports on radiological findings for small bowel bezoars. Barium studies characteristically show an intraluminal filling defect of variable size that is not fixed to the bowel wall with barium filling the interstices giving a mottled appearance. On CT scan, the presence of a round or ovoid intraluminal mass with a 'mottled gas' pattern is believed to be pathognomonic. Since features on CT scans are characteristics and physical findings are of little assistance in the diagnosis of bezoar, the diagnostic value of CT needs to be emphasised.
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