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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.
Leiomyoma of the incisive papilla region: a case report

Ng KH, Siar CH, Abdul Latif H

Ann Dent, 1992;51(1):29-31.
PMID: 1632624

Leiomyomas are benign neoplasms of smooth muscle origin. They represent rare entities in the oral cavity. A case arising from the incisive papilla region of a 3-month-old infant is described and the histogenesis as well as the biologic potential of this tumor are discussed.
A nationwide survey on awareness and knowledge about Bronchial Provocation Test amongst doctors in Malaysia

Ng KL, Huan NC, Mohammad FA, Mohd Aminudin NH, Mohammad FA, Abdul Rahaman JA

Med J Malaysia, 2022 Jan;77(1):33-40.
PMID: 35086992

BACKGROUND: Bronchial provocation test (BPT) is widely used internationally not only to evaluate bronchial responsiveness in conditions especially asthma, but is also utilized as a marker of control, severity and prognosis for asthma. However, the uptake of BPT in certain countries including Malaysia remains low. We aimed to explore this lack of knowledge by assessing the current level of awareness and knowledge on BPT amongst doctors in Malaysia.
MATERIALS AND METHODS: A nationwide web-based questionnaire targeting doctors was sent through social media (Facebook, WhatsApp and Telegram) and Malaysian Medical Association (MMA) mailing lists between 1 October 2020 - 5 February 2021.
RESULTS: In all 415 survey responses were analysed from doctors of various grades namely medical officers to consultants. A total of 404 (97.35%) encountered patients with asthma in their daily practice. According to specialty: 169 (40.72%) were from primary care, 121 (29.16%) internal medicine, 50 (12.05%) pulmonary medicine and 75 (18.07%) others. Only 163 (39.28%) were aware of BPT as a tool to diagnose asthma. 232 (55.90%) and 124 (29.88%) regarded BPT as an important test and felt confident to refer patients for BPT respectively. Of those participants who were not confident to refer: 35.17% were unsure of BPT indications, 33.21% were unsure of centres providing BPT, 8.17% cited logistic reasons, 6.04% were concerned of possible BPT side effects. 387 (93.25%) wanted more training in BPT. The median BPT knowledge score was 20% (1 out of 5). Awareness and knowledge were affected by specialty but not by: region of practice, gender, age and grade from logistic regression analysis.
CONCLUSION: Various national level programs and targeted local interventions are much needed to increase the awareness, knowledge and uptake of BPT in Malaysia.
A low cost solution for post-biopsy complications using available RFA generator and coaxial core biopsy needle

Azlan CA, Mohd Nasir NF, Saifizul AA, Faizul MS, Ng KH, Abdullah BJ

Australas Phys Eng Sci Med, 2007 Dec;30(4):288-91.
PMID: 18274069

Percutaneous image-guided needle biopsy is typically performed in highly vascular organs or in tumours with rich macroscopic and microscopic blood supply. The main risks related to this procedure are haemorrhage and implantation of tumour cells in the needle tract after the biopsy needle is withdrawn. From numerous conducted studies, it was found that heating the needle tract using alternating current in radiofrequency (RF) range has a potential to minimize these effects. However, this solution requires the use of specially designed needles, which would make the procedure relatively expensive and complicated. Thus, we propose a simple solution by using readily available coaxial core biopsy needles connected to a radiofrequency ablation (RFA) generator. In order to do so, we have designed and developed an adapter to interface between these two devices. For evaluation purpose, we used a bovine liver as a sample tissue. The experimental procedure was done to study the effect of different parameter settings on the size of coagulation necrosis caused by the RF current heating on the subject. The delivery of the RF energy was varied by changing the values for delivered power, power delivery duration, and insertion depth. The results showed that the size of the coagulation necrosis is affected by all of the parameters tested. In general, the size of the region is enlarged with higher delivery of RF power, longer duration of power delivery, and shallower needle insertion and become relatively constant after a certain value. We also found that the solution proposed provides a low cost and practical way to minimizes unwanted post-biopsy effects.
A proposed hierarchical fuzzy inference system for the diagnosis of arthritic diseases

Lim CK, Yew KM, Ng KH, Abdullah BJ

Australas Phys Eng Sci Med, 2002 Sep;25(3):144-50.
PMID: 12416592 DOI: 10.1007/BF03178776

Development of computer-based medical inference systems is always confronted with some difficulties. In this paper, difficulties of designing an inference system for the diagnosis of arthritic diseases are described, including variations of disease manifestations under various situations and conditions. Furthermore, the need for a huge knowledge base would result in low efficiency of the inference system. We proposed a hierarchical model of the fuzzy inference system as a possible solution. With such a model, the diagnostic process is divided into two levels. The first level of the diagnosis reduces the scope of diagnosis to be processed by the second level. This will reduce the amount of input and mapping for the whole diagnostic process. Fuzzy relational theory is the core of this system and it is used in both levels to improve the accuracy.
Fulltext Tsukamurella tyrosinosolvens intravascular catheter-related bacteremia in a haematology patient: a case report

Karunakaran R, Halim HA, Ng KP, Hanifah YA, Chin E, Jaafar FL, et al.

Eur Rev Med Pharmacol Sci, 2011 Nov;15(11):1343-6.
PMID: 22195371

Tsukamurella spp. are a rare but important cause of intravascular catheter-related bacteremia in immunocompromised patients. The organism is an aerobic, Gram-positive, weakly acid-fast bacillus that is difficult to differentiate using standard laboratory methods from other aerobic actinomycetales such as Nocardia spp., Rhododoccus spp., Gordonia spp., and the rapid growing Mycobacterium spp. We report a case of Tsukamurella tyrosinosolvens catheter-related bacteremia in a 51-year-old haematology patient who responded to treatment with imipenem and subsequent line removal. 16srRNA sequencing allowed for the prompt identification of this organism.
A large exposure to Brucella melitensis in a diagnostic laboratory

Sam IC, Karunakaran R, Kamarulzaman A, Ponnampalavanar S, Syed Omar SF, Ng KP, et al.

J Hosp Infect, 2012 Apr;80(4):321-5.
PMID: 22237130 DOI: 10.1016/j.jhin.2011.12.004

Brucella species are easily transmitted by aerosols and can be acquired in the laboratory.
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.
Dermatophytes isolated from patients in University Hospital, Kuala Lumpur, Malaysia

Ng KP, Soo-Hoo TS, Na SL, Ang LS

Mycopathologia, 2002;155(4):203-6.
PMID: 12650596

A total of 576 dermatophytes were isolated from patients with a variety of skin infections from January 1993 to May 2000. Ten species of dermatophytes were identified: Epidermophyton floccosum (0.7%), Microsporum audouinii (1.1%), M. canis (3.1%), M. gypseum (0.3%), Trichophyton concentricum (3.5%), T. equinum (0.2%), T. mentagrophytes (36.1%), T. rubrum (53.8%), T. verrucosum (0.2) and T. violaceum (1.0%). The body sites most frequently affected by dermatophytes were the buttocks, nails and trunk. Anthropophilic dermatophytes made up 60.1% of the isolates; the most common species was T. rubrum, T. mentagrophytes and M. canis were the two main zoophilic dermatophytes. T. mentagrophytes was isolated from all body sites except the scalp. M. canis was found to be associated with domestic dogs and was not isolated from ethnic Malays. The only geophilic dermatophyte was M. gypseum, an uncommon dermatophyte associated with tinea pedis.
Risk of flare and damage accrual after tapering glucocorticoids in modified serologically active clinically quiescent patients with systemic lupus erythematosus: a multinational observational cohort study

Katsumata Y, Inoue E, Harigai M, Cho J, Louthrenoo W, Hoi A, et al.

Ann Rheum Dis, 2024 Feb 29.
PMID: 38423757 DOI: 10.1136/ard-2023-225369

OBJECTIVES: To assess the risk of flare and damage accrual after tapering glucocorticoids (GCs) in modified serologically active clinically quiescent (mSACQ) patients with systemic lupus erythematosus (SLE).
METHODS: Data from a 12-country longitudinal SLE cohort, collected prospectively between 2013 and 2020, were analysed. SLE patients with mSACQ defined as the state with serological activity (increased anti-dsDNA and/or hypocomplementemia) but without clinical activity, treated with ≤7.5 mg/day of prednisolone-equivalent GCs and not-considering duration, were studied. The risk of subsequent flare or damage accrual per 1 mg decrease of prednisolone was assessed using Cox proportional hazard models while adjusting for confounders. Observation periods were 2 years and censored if each event occurred.
RESULTS: Data from 1850 mSACQ patients were analysed: 742, 271 and 180 patients experienced overall flare, severe flare and damage accrual, respectively. Tapering GCs by 1 mg/day of prednisolone was not associated with increased risk of overall or severe flare: adjusted HRs 1.02 (95% CI, 0.99 to 1.05) and 0.98 (95% CI, 0.96 to 1.004), respectively. Antimalarial use was associated with decreased flare risk. Tapering GCs was associated with decreased risk of damage accrual (adjusted HR 0.96, 95% CI, 0.93 to 0.99) in the patients whose initial prednisolone dosages were >5 mg/day.
CONCLUSIONS: In mSACQ patients, tapering GCs was not associated with increased flare risk. Antimalarial use was associated with decreased flare risk. Tapering GCs protected mSACQ patients treated with >5 mg/day of prednisolone against damage accrual. These findings suggest that cautious GC tapering is feasible and can reduce GC use in mSACQ patients.
Fulltext Physicochemical, pasting and gel textural properties of wheat-ripe Cavendish banana composite flours

Ng, K. F., Abbas, F. M. A., Tan, T. C., Azhar, M. E.

International Food Research Journal, 2014;21(2):655-662.
MyJurnal

Proximate composition, pH and amylose content of ripe Cavendish banana flour (RBF) prepared in this study were compared with all-purpose wheat flour (WF). RBF was found to be significantly (P < 0.05) higher in total carbohydrates and minerals content, while significantly (P < 0.05) lower in protein and fat contents compared with those of WF. Wheat-ripe banana composite flours (W-RBF) prepared by partial substitution of WF with RBF were assessed for swelling power, solubility, pasting properties and gel textural properties. Granular swelling of RBF occurred at a higher temperature compared to that of WF, suggesting that more energy and water were required to cook WF-RBF as the presence of soluble carbohydrates would compete for water and this would eventually delay starch hydration and granular expansion during cooking. Higher substitution with RBF led to higher soluble carbohydrates content, and increase in solubility index of WF-RBF. Partial substitution with RBF also resulted in significant (P < 0.05) decrease in pasting properties. A higher substitution of WF with RBF could reduce starch gelatinisation during cooking and retrogradation owing to the reduction of available starch in WF-RBF. All WF-RBF gels were significantly (P < 0.05) firmer and less sticky compared to WF gels.
Use of a modified natural-rubber phantom for radiotherapy dosimetry measurements

Bradley DA, Ng KH, Aziz YB

Int J Rad Appl Instrum A, 1988;39(5):439-40.
PMID: 2840420

The utility of a phantom material, based on SMR(L) [Standard Malaysian Rubber] grade natural rubber and a formulation used for the proprietary rubber phantom-material, Temex, has been examined for the 1-MeV photon-Measurement has also been performed with 60-keV photons using the radionuclide 241Am. At photon-therapy energy levels the measured response, when compared with tabulated central-axis percentage depth doses for the defined measuring conditions, produces everywhere (in the range 1-19 cm depth) better than 2% deviation. The favourable measured response characteristics combined with the ease of processing and casting the phantom material provide the basis for useful radiotherapy machine calibration and anthropomorphic dosimetry measurements. The measured mass-attenuation coefficient, at 60keV, of 0.204 cm2 g-1 (+/- 3%) is in close agreement with tabulated values for water (0.2055 cm2 g-1).
A study of hospitalized COVID-19 patients with AKI in a setting of multiracial developing country

Ooi SH, Ng KP, Sthaneshwar P, Lim SK, Khor PY, Lim JY, et al.

BMC Nephrol, 2024 Apr 05;25(1):122.
PMID: 38580977 DOI: 10.1186/s12882-024-03498-x

BACKGROUND: The commonest indication for hospitalization in COVID-19 patients is hypoxemia or severe respiratory symptoms. However, COVID-19 disease may result in extrapulmonary complications including kidney-related pathology. The reported incidence of renal involvement related to COVID infection varies based on geographical location.
OBJECTIVE: This study aimed to assess the incidence rate of AKI in hospitalized COVID-19 patients and identify risk factors and prognostic predictors.
METHOD: In this retrospective study, we recruited hospitalized COVID-19 patients from January 2021 until June 2021 at the University Malaya Medical Center. The inclusion criteria were hospitalized for ≥ 48 h with confirmed COVID-19 infection and at least 18 years old. Patient demographic and clinical data were collected from electronic medical records. The staging of AKI was based on criteria as per KDIGO guidelines.
RESULTS: One thousand five hundred twenty-nine COVID patients fulfilled the inclusion criteria with a male-to-female ratio of 759 (49.6%) to 770 (50.3%). The median age was 55 (IQR: 36-66). 500 patients (32.7%) had diabetes, 621 (40.6%) had hypertension, and 5.6% (n = 85) had pre-existing chronic kidney disease (CKD). The incidence rate of AKI was 21.1% (n = 323). The percentage of COVID patients in different AKI stages of 1,2 and 3 were 16.3%, 2.1%, and 2.7%, respectively. Fifteen hospitalized patients (0.98%) required renal replacement therapy. 58.8% (n = 190) of AKI group had complete recovery of kidney function. Demographic factors included age (p
Fulltext A parallel spatiotemporal saliency and discriminative online learning method for visual target tracking in aerial videos

Aghamohammadi A, Ang MC, A Sundararajan E, Weng Ng K, Mogharrebi M, Banihashem SY

PLoS One, 2018;13(2):e0192246.
PMID: 29438421 DOI: 10.1371/journal.pone.0192246

Visual tracking in aerial videos is a challenging task in computer vision and remote sensing technologies due to appearance variation difficulties. Appearance variations are caused by camera and target motion, low resolution noisy images, scale changes, and pose variations. Various approaches have been proposed to deal with appearance variation difficulties in aerial videos, and amongst these methods, the spatiotemporal saliency detection approach reported promising results in the context of moving target detection. However, it is not accurate for moving target detection when visual tracking is performed under appearance variations. In this study, a visual tracking method is proposed based on spatiotemporal saliency and discriminative online learning methods to deal with appearance variations difficulties. Temporal saliency is used to represent moving target regions, and it was extracted based on the frame difference with Sauvola local adaptive thresholding algorithms. The spatial saliency is used to represent the target appearance details in candidate moving regions. SLIC superpixel segmentation, color, and moment features can be used to compute feature uniqueness and spatial compactness of saliency measurements to detect spatial saliency. It is a time consuming process, which prompted the development of a parallel algorithm to optimize and distribute the saliency detection processes that are loaded into the multi-processors. Spatiotemporal saliency is then obtained by combining the temporal and spatial saliencies to represent moving targets. Finally, a discriminative online learning algorithm was applied to generate a sample model based on spatiotemporal saliency. This sample model is then incrementally updated to detect the target in appearance variation conditions. Experiments conducted on the VIVID dataset demonstrated that the proposed visual tracking method is effective and is computationally efficient compared to state-of-the-art methods.
Fulltext Immunogenicity and Safety of the AS04-adjuvanted Human Papillomavirus-16/18 Cervical Cancer Vaccine in Malaysian Women Aged 18-35 years: A Randomized Controlled Trial

Lim BK, Ng KY, Omar J, Omar SZ, Gunapalaiah B, Teoh YL, et al.

Med J Malaysia, 2014 Feb;69(1):2-8.
PMID: 24814620

INTRODUCTION: Cervical cancer is the third most common cancer in women worldwide. The HPV-16/18 AS04- adjuvanted vaccine (Cervarix©) has previously been shown to be highly immunogenic with a clinically acceptable safety profile. This phase IIIb, double-blind, randomized (1:1) and placebo controlled trial (NCT00345878) was designed to evaluate the vaccine immunogenicity against HPV-16 and HPV-18 as well as its safety and reactogenicity in Malaysian women.

METHODS: Healthy women aged 18-35 years received intramuscularly three doses of either the vaccine (HPV group) or aluminium hydroxide (ALU group) at 0, 1, and 6 months. Antibody titers were measured by an enzyme-linked immunosorbent assay (ELISA).

RESULTS: A total of 271 eligible subjects were enrolled and 266 subjects completed the study. Initially seronegative subjects in the HPV group showed 100% seroconversion one month post-dose-3 for anti HPV-16 and anti-HPV-18 antibodies with geometric mean titers of 11107.5 (95% CI: 9727.3-12683.4) EL.U/mL and 4273.5 (95% CI: 3771.8-4841.9) EL.U/mL, respectively. Over 96% of subjects in both groups received all three vaccine doses. Solicited local (pain) and general symptoms (myalgia, fatigue, arthralgia and headache) were commonly reported in both HPV and ALU groups. Eight serious adverse events were reported throughout the study (five in the HPV group; three in the ALU group), all considered by investigators to be unrelated to vaccination.

CONCLUSION: The HPV-16/18 AS04-adjuvanted vaccine was immunogenic and generally well tolerated in Malaysian women aged 18-35 years.
Microcalcification clustering parameters in breast disease: a morphometric analysis of radiographs of excision specimens

Ng KH, Looi LM, Bradley DA

Br J Radiol, 1996 Apr;69(820):326-34.
PMID: 8665132

X-ray microradiography of surgically excised breast specimens offers the possibility of morphological characterization of calcifications. When combined with digital imaging techniques there exists added potential for obtaining valuable basic quantitative morphometric information regarding differences between microcalcifications in tissues exhibiting evidence of fibrocystic change, benign and malignant tumours. A total of 157 excised breast specimens from 84 patients were microradiographed using a Softex Super Soft X-ray unit and Kodak AA high resolution industrial film. A Quantimet 570C image analysis system was used to digitize and analyse the microradiographs. Of the 157 microradiographs, 51 (from 30 patients) revealed microcalcification clusters. The existence of significant differences between the three identified categories of tissue were indicated by clustering parameters. These included the number of particles per cluster, area of clusters, maximum distance to nearest neighbour, and geometric mean distance to nearest neighbour. The distribution pattern index (DPI), another of the clustering parameters used in this study, has been observed to be a particularly powerful discriminator. The value for fibrocystic change was found to be significantly smaller (0.514) than that for benign tumour (0.796) whilst that for benign tumour was observed to be significantly larger than that for malignant tumour (0.604) at a p-value of less than 0.05 (Kruskal-Wallis one-way analysis of variance).
Retrospective review of spinal versus epidural anaesthesia for caesarean section in preeclamptic patients

Chiu CL, Mansor M, Ng KP, Chan YK

Int J Obstet Anesth, 2003 Jan;12(1):23-7.
PMID: 15676316

A 5-year retrospective survey of anaesthesia for caesarean section for mild/moderate and severe preeclampsia was performed, covering the period between 1 January 1996 and 31 December 2000. One hundred and twenty-one cases of non-labouring preeclamptic patients receiving spinal or epidural anaesthesia for caesarean section were included for analysis. Comparisons were made of the lowest blood pressures recorded before induction of anaesthesia, during the period from induction to delivery and the period from delivery to the end of operation. The decreases in blood pressure were similar after spinal and epidural anaesthesia. The use of intravenous fluids and ephedrine were also comparable in the two anaesthetic groups. There was no difference in maternal or neonatal outcome. Our result supports the use of spinal anaesthesia in preeclamptic women.
Squamous cell carcinoma of the oral mucosa in Malaysia--any change?

Ng KH, Siar CH, Ramanathan K, Murugasu P, Chelvanayagam PI

Southeast Asian J. Trop. Med. Public Health, 1985 Dec;16(4):602-6.
PMID: 3835704

The prevalence rate of 749 cases of oral squamous cell carcinomas (SCC) recorded between 1978-1984 was studied. Results showed that the Indians formed the dominant group (63.8%) followed by the Malays (19.6%) and Chinese (16.6%). The peak incidences were generally located between the sixth and eighth decades. Only in the Chinese group a male preponderance was noted. In the Indians, the buccal mucosa was the most prevalent site; in the Malays and Chinese males, the gingiva and alveolus; and the Chinese female, the tongue. In all three groups, the well-differentiated SCC was the commonest type and the poorly differentiated least common.
Combined granular cell ameloblastoma and plexiform granular cell odontogenic tumour

Siar CH, Ng KH, Chia TY

Singapore Dent J, 1990 Dec;15(1):35-7.
PMID: 2097728

Granular cell ameloblastomas are uncommon lesions accounting for about 3-5% of all histologic subtypes of ameloblastoma. The plexiform granular cell odontogenic tumour, on the other hand, is a newly described lesion characterised by a monophasic plexiform pattern of granular cells. This article reports a tumour found occurring in the left mandible of a 67-year-old Indian male which histologically showed features of both the aforementioned lesions.
Erysipelothrix rhusiopathiae endocarditis presenting with stroke

Tan YA, Ng KC, Cheo SW, Low QJ, Chia YK

QJM, 2020 07 01;113(7):485-487.
PMID: 32053172 DOI: 10.1093/qjmed/hcaa025

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