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Fulltext Non-evaporative method to remove high boiling point solvent (ethyl lactate) from palm oil extract at atmospheric conditions

Kua, Y. L., Gan, S., Morris, A., Ng, H. K.

International Food Research Journal, 2018;25(101):97-103.
MyJurnal

Ethyl lactate was demonstrated as a green and efficient agrochemical solvent to concentrate phytonutrients such as carotenes and tocols in palm oil. However, the removal of this solvent from the extract is difficult and expensive due to its very high boiling point and low volatility. Heating at high temperature in an effort to evaporate the solvent is undesirable even under reduced pressure as the extracted phytonutrients are heat-sensitive compounds. In this paper, a non-evaporative method using only water was proposed for the first time to remove the solvent at atmospheric conditions based on its solubility difference instead of the vapour pressure difference. The proposed method was proved to be more effective, faster and cheaper as compared to conventional approaches such as rotary evaporation, freeze drying and vacuum drying.
Fulltext An experimental and modelling study of selected heavy metals removal from aqueous solution using Scylla Serrata as biosorbent

Aris A. Z., Ismail F. A., Ng, H. Y., Praveena, S. M.

Pertanika Journal of Science & Technology, 2014;22(2):553-566.
MyJurnal

This study was conducted using crab shells as a biosorbent to remove Cu and Cd with different initial concentrations of 1, 5, 10, 15, and 20 mg/L in a biosorption treatment process. Crab shells were selected as biosorbents due to their abundance in the environment and ready availability as waste products from the market place. This study aimed to determine the ability of Scylla Serrata shells to remove Cu and Cd in an aqueous solution, as well as to provide a comparison of the removal rate between the two metals. The data were incorporated into hydrochemical software, PHREEQC, to investigate the chemical speciation distribution of each heavy metal. The shells of S. serrata were found to have a significant (p< 0.05) ability to remove Cu and Cd following the treatment. After six hours of treatment, the crab shells had removed 60 to 80% of both metals. However, the highest removal percentage was achieved for Cu with up to 94.7% removal rate in 5 mg/L initial Cu concentration, while 85.1% of Cd was removed in 1 mg/L initial solution, respectively. It can be concluded that the shells of S. serrata could remove Cu and Cd better with significant results (p
Application of vegetable oils in the treatment of polycyclic aromatic hydrocarbons-contaminated soils

Yap CL, Gan S, Ng HK

J Hazard Mater, 2010 May 15;177(1-3):28-41.
PMID: 20006435 DOI: 10.1016/j.jhazmat.2009.11.078

A brief review is conducted on the application of vegetable oils in the treatment of PAH-contaminated soils. Three main scopes of treatment strategies are discussed in this work including soil washing by oil, integrated oil-biological treatment and integrated oil-non-biological treatment. For each of these, the arguments supporting vegetable oil application, the applied treatment techniques and their efficiencies, associated factors, as well as the feasibility of the techniques are detailed. Additionally, oil regeneration, the environmental impacts of oil residues in soil and comparison with other commonly employed techniques are also discussed.
Remediation of soils contaminated with polycyclic aromatic hydrocarbons (PAHs)

Gan S, Lau EV, Ng HK

J Hazard Mater, 2009 Dec 30;172(2-3):532-49.
PMID: 19700241 DOI: 10.1016/j.jhazmat.2009.07.118

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic micropollutants which are resistant to environmental degradation due to their highly hydrophobic nature. Concerns over their adverse health effects have resulted in extensive studies on the remediation of soils contaminated with PAHs. This paper aims to provide a review of the remediation technologies specifically for PAH-contaminated soils. The technologies discussed here include solvent extraction, bioremediation, phytoremediation, chemical oxidation, photocatalytic degradation, electrokinetic remediation, thermal treatment and integrated remediation technologies. For each of these, the theories are discussed in conjunction with comparative evaluation of studies reported in the specialised literature.
Fulltext The correlation between cytopenia and esophageal varices in patients with liver cirrhosis

Gue CS, Yap CK, Ng HS

Med J Malaysia, 2004 Dec;59(5):604-8.
PMID: 15889562

This retrospective study analysed the case records of 200 patients in the Department of Gastroenterology, Singapore General Hospital from February 2000 to January 2001 who had liver cirrhosis and underwent gastroscopy for the detection of varices. The aim of this study was to determine any relationship between leucopenia, thrombocytopenia and the occurrence of esophageal varices in a cirrhotic population. Our results showed that the diagnostic yield of varices grade 2 and 3 was 6.3% if platelet count was > 150,000/mm3, 25% if platelet count was 100,000 to 150,000/mm3, 38.9% if platelet count was 50,000-99,000/mm3 and 100% if platelet count was <50,000/mm3. Similarly, the diagnostic yield of varices grade 2 and 3 was 19.4% if total white count was > 4,000/mm3, 66.7% if total white count was 3,000- 4,000/mm3 and 94.8% if total white count was < 3,000/mm5. We conclude that thrombocytopenia and leucopenia can be used to stratify risk for occurrence of esophageal varices in cirrhotic patients and gastroscopy will have a high yield for varices when platelet count is < 150,000/mm3 or total white is < 4,000/mm.
Fulltext Gastrointestinal Cytomegalovirus infection in non-human immunodeficiency virus infected patients

Ng KL, Ho J, Ng HS, Luman W

Med J Malaysia, 2003 Aug;58(3):337-44.
PMID: 14750372

This is a retrospective study of fourteen patients who had proven Cytomegalovirus (CMV) infection of the gastrointestinal tract with no Human Immunodeficiency virus infection. The median age was 60.5 (Range 28 to 81) years. Eight patients were below (Group 1) and six above sixty five years old (Group 2). Areas of gastro-intestinal involvement were: oesophagus (2), stomach (1), colon (10) and multiple sites (1). Seven patients from Group 1 had received immunosuppressive therapy at the time of presentation and one had diabetes mellitus. We found a high prevalence of co-morbidities such as chronic renal failure and diabetes mellitus in Group 2. At median follow up of 13.9 months, there was a mortality rate of 50%. Only four patients were treated with ganciclovir. Our study concludes that the gastrointestinal CMV diseases in young patients were associated with immunosuppression whereas the older patients had chronic renal failure or diabetes.
Fulltext Extraction techniques for polycyclic aromatic hydrocarbons in soils

Lau EV, Gan S, Ng HK

Int J Anal Chem, 2010;2010:398381.
PMID: 20396670 DOI: 10.1155/2010/398381

This paper aims to provide a review of the analytical extraction techniques for polycyclic aromatic hydrocarbons (PAHs) in soils. The extraction technologies described here include Soxhlet extraction, ultrasonic and mechanical agitation, accelerated solvent extraction, supercritical and subcritical fluid extraction, microwave-assisted extraction, solid phase extraction and microextraction, thermal desorption and flash pyrolysis, as well as fluidised-bed extraction. The influencing factors in the extraction of PAHs from soil such as temperature, type of solvent, soil moisture, and other soil characteristics are also discussed. The paper concludes with a review of the models used to describe the kinetics of PAH desorption from soils during solvent extraction.
Ocular leptospirosis in four patients: A diagnostic dilemma

Ng HR, Cheong MY, Mustapha M

Med J Malaysia, 2021 07;76(4):569-572.
PMID: 34305121

Leptospirosis is a zoonotic disease that is caused by the pathogenic spirochetes of the genus Leptospira. The infection occurs worldwide and is particularly more common in the tropics. However, it is becoming a neglected reemerging global health disease due to rapid urbanisation. This disease has a wide range of clinical manifestations from flu-like illness to pneumonia, acute kidney injury, etc. But many uncommon clinical findings are being reported as well. In this paper, we report four patients who presented initially with uveitic features who turned out serologically positive for Leptospira after extensive investigations.
Fulltext Development of vision based multiview gait recognition system with MMUGait database

Ng H, Tan WH, Abdullah J, Tong HL

ScientificWorldJournal, 2014;2014:376569.
PMID: 25143972 DOI: 10.1155/2014/376569

This paper describes the acquisition setup and development of a new gait database, MMUGait. This database consists of 82 subjects walking under normal condition and 19 subjects walking with 11 covariate factors, which were captured under two views. This paper also proposes a multiview model-based gait recognition system with joint detection approach that performs well under different walking trajectories and covariate factors, which include self-occluded or external occluded silhouettes. In the proposed system, the process begins by enhancing the human silhouette to remove the artifacts. Next, the width and height of the body are obtained. Subsequently, the joint angular trajectories are determined once the body joints are automatically detected. Lastly, crotch height and step-size of the walking subject are determined. The extracted features are smoothened by Gaussian filter to eliminate the effect of outliers. The extracted features are normalized with linear scaling, which is followed by feature selection prior to the classification process. The classification experiments carried out on MMUGait database were benchmarked against the SOTON Small DB from University of Southampton. Results showed correct classification rate above 90% for all the databases. The proposed approach is found to outperform other approaches on SOTON Small DB in most cases.
Fulltext Lack of association between RANTES-28, SDF-1 gene polymorphisms and systemic lupus erythematosus in the Malaysian population

Lian LH, Kee BP, Ng HL, Chua KH

Genet. Mol. Res., 2011;10(4):2841-50.
PMID: 22095608 DOI: 10.4238/2011.November.17.2

Regulated on activation, normal T-cell expressed and secreted (RANTES) and stromal cell-derived factor 1 (SDF-1) are members of the CC- and CXC-chemokine families, respectively. Both genes have been postulated to be involved in the pathogenesis of systemic lupus erythematosus (SLE). We analyzed position 28 of the RANTES gene promoter region, as well as the SNP observed in the 3' UTR of the SDF-1 gene at position 801, in 130 patients presenting SLE at the Malaya University Medical Centre. Screening of 130 healthy volunteer controls using RFLP was also performed. RANTES-28 polymorphism analysis showed no significant (P = 0.3520) relationship, even though homozygous C/C was more frequent in SLE patients (OR = 1.4183) and heterozygous C/G was more frequent in healthy controls (OR = 0.7051). There were no significant (P = 0.2650) associations between A/A (OR = 0.783), G/G (OR = 1.5914) and G/A (OR = 0.8289) genotypes in the SDF-1 gene polymorphism with SLE. We conclude that there is no significant association of RANTES-28 and SDF-1 gene polymorphisms and occurrence of SLE in Malaysia.
Fulltext Pattern of congenital heart disease and access to tertiary cardiac care in Malaysia

Hung LC, Mohan AJ, Soo TL, Ng HP

Med J Malaysia, 2000 Dec;55(4):424-32.
PMID: 11221153

This prospective, descriptive study was carried out to determine the pattern and the type of congenital heart disease seen in the Paediatric Departments in 4 government hospitals. The accessibility of surgical or transcatheter interventional treatment was also assessed. Consecutive new patients seen for suspected congenital heart disease from 1/1/95 till 31/12/95 (Group I) were registered. Records of patients seen from 1/1/95 to 31/8/95 (Group Ia) were reviewed 6 months after presentation to determine the nature of treatment received. Group II were cardiac patients who were first seen prior to the year 1995 and had undergone cardiac surgery or transcatheter interventional procedures in 1995. Of the 375 patients registered in the 4 hospitals, 250 were new patients and 125 were patients first seen prior to 1995 and had surgery or transcatheter interventional procedures in 1995. Of the 250 new patients, 83.2% had acyanotic cardiac lesions and 16.8% had cyanotic lesions. Ventricular septal defect was the commonest lesion, constituting 37.2%, followed by patent arterial duct (18.8%) and atrial septal defects (9.6%). At 6 month review, access to close-heart surgery or transcatheter interventional treatment were readily available. However, for patients with ventricular septal defects, 42.1% who required closure were still waiting for surgery 6 months after presentation. Of the 4 patients with Fallot's Tetralogy who required surgery, 2 had modified Blalock-Taussig shunt and 2 were awaiting surgery. In 1995, a total of 204 cardiac procedures were performed, there were 114 (55.9%) open heart procedures, 50 (24.5%) surgical ligation of the arterial duct, 28 (13.7%) modified Blalock-Taussig shunts, 11 (5.4%) transcatheter duct occlusion and 1 (0.5%) balloon valvuloplasty. The mean age of Fallot's Tetralogy repair was 6.4 years. No corrective surgery was performed for patients with complex cardiac lesions from the 4 hospitals in 1995. In conclusion, the pattern of congenital heart disease was similar to that seen world wide. Except for patent arterial duct, access to surgical treatment was inadequate.
D1S80 (pMCT118) allele frequencies in a Malay population sample from Malaysia

Koh CL, Lim ME, Ng HS, Sam CK

Int J Legal Med, 1997;110(1):39-40.
PMID: 9081241

The D1S80 allele frequencies in 124 unrelated Malays from the Malaysian population were determined and 51 genotypes and 19 alleles were encountered. The D1S80 frequency distribution met Hardy-Weinberg expectations. The observed heterozygosity was 0.80 and the power of discrimination was 0.96.
Fulltext Poly(Acrylic acid)⁻Based Hybrid Inorganic⁻Organic Electrolytes Membrane for Electrical Double Layer Capacitors Application

Liew CW, Ng HM, Numan A, Ramesh S

Polymers (Basel), 2016 May 18;8(5).
PMID: 30979292 DOI: 10.3390/polym8050179

Nanocomposite polymer electrolyte membranes (NCPEMs) based on poly(acrylic acid)(PAA) and titania (TiO₂) are prepared by a solution casting technique. The ionic conductivity of NCPEMs increases with the weight ratio of TiO₂.The highest ionic conductivity of (8.36 ± 0.01) × 10-4 S·cm-1 is obtained with addition of 6 wt % of TiO₂ at ambient temperature. The complexation between PAA, LiTFSI and TiO₂ is discussed in Attenuated total reflectance-Fourier Transform Infrared (ATR-FTIR) studies. Electrical double layer capacitors (EDLCs) are fabricated using the filler-free polymer electrolyte or the most conducting NCPEM and carbon-based electrodes. The electrochemical performances of fabricated EDLCs are studied through cyclic voltammetry (CV) and galvanostatic charge-discharge studies. EDLC comprising NCPEM shows the specific capacitance of 28.56 F·g-1 (or equivalent to 29.54 mF·cm-2) with excellent electrochemical stability.
25S rDNA genotyping and multi-locus sequence typing of Candida albicans of pathogenic and commensal origins in the Klang Valley, Malaysia

Illyaaseen Z, Ngeow YF, Yap SF, Ng HF

Malays J Pathol, 2021 Apr;43(1):55-61.
PMID: 33903306

Candida albicans is an important opportunistic fungal pathogen capable of causing fatal systemic infections in humans. Presently in Malaysia, there is little information available on the genetic diversity of this organism and trends in behavioural characteristics. In this project, three genotyping methods: 25S rDNA genotyping, Alternative Lengthening of Telomerase (ALT) sequence typing and Multi-Locus Sequence Typing (MLST) were applied to study the genetic diversity of strains from infected hospital in-patients and asymptomatic individuals in the community. The results showed that, with the 25S rDNA genotyping, as in other parts of the world, the most common genotype was type A which accounted for approximately 70% of the 111 isolates tested. Further typing with the ALT sequence showed type 3 to be the most common in the isolates tested. MLST analysis revealed many possibly novel sequence types, as well as a statistically significant association between pathogenicity and a group of closely related isolates, most of which were from hospital samples. Further work on genotypes associated with enhanced virulence will help to clarify the value of genotyping for clinical and epidemiological investigations.
Evaluation of visual outcomes after toric intraocular lens implantation

Ng HR, Goh CH, Ngim YS, Juliana J

Med J Malaysia, 2017 12;72(6):356-359.
PMID: 29308773 MyJurnal

PURPOSE: To evaluate postoperative visual acuity, refractive status and rotational stability of toric intraocular lens (IOL) in correcting pre-existing corneal astigmatism.
METHODS: A total of 69 patients with topographic corneal astigmatism of 1.0 Diopter (D) and above who underwent cataract surgery between June 2015 and December 2016 were included in this retrospective observational study. All preoperative toric IOL calculations were performed using immersion biometry. Appropriate formula to calculate toric IOL power was applied (SRK/T, Holladay 1 or Hoffer Q formula). All patients undergone similar uncomplicated phacoemulsification with implantation of AcrySoft IQ SN6AT toric IOL of different powers. Visual outcome, refractive status and axis of lens were evaluated at six weeks postoperatively. Ethical approval from the Ministry of Health Medical Research Ethics Committee was obtained prior to commencement of study.
RESULTS: The mean refractive astigmatism decreased from 1.69 D ±1.10 (SD) to 0.81 D ± 0.40 (SD) at six weeks postoperatively. The mean postoperative spherical equivalent was at -0.37 D ±0.64 (SD). Mean LogMAR for uncorrected and corrected distance visual acuity in six weeks postoperative patients was at 0.29 ±0.16 (SD) and 0.12 ±0.12 (SD) respectively. Intraoperative to 6 weeks of postoperative comparison of IOL axis alignment showed low levels of rotation (mean 3.21 ±2.52 degrees).
CONCLUSION: Cataract surgery with implantation of toric IOL was stable and effective in improving pre-existing regular corneal astigmatism.
Fulltext Immunohistochemical study of p16 INK4A and survivin expressions in cervical squamous neoplasm

Tan GC, Norlatiffah S, Sharifah NA, Razmin G, Shiran MS, Hatta AZ, et al.

Indian J Pathol Microbiol, 2010 Jan-Mar;53(1):1-6.
PMID: 20090212 DOI: 10.4103/0377-4929.59173

Cervical cancer is the second most common cancer affecting Malaysian women. Despite the implementation of pap smear screening, many women are still diagnosed only in the advanced stage of cervical cancer. This could partly be due to failure of detection of its precursor lesions; hence the need to search for novel biomarkers to assist in the screening and diagnosis of cervical neoplasia. This study aims to determine the expression of p16INK4A and survivin as possible predictive biomarkers in cervical squamous neoplasm.
Fulltext Neonatal post-intubation subglottic stenosis

Loi HDK, Parhr AS, Subramaniam SK, Choo KE, Ng HP

Med J Malaysia, 2004 Mar;59(1):126-8.
PMID: 15535351

Acquired subglottic stenosis is a compication or neonatal endotracheal intubation. Although it is rare, it contributes significantly to the morbidity and physical well being of post extubated neonates. A 20-day old neonate, ventilated for meconium aspiration syndrome and persistent fetal circulation, presented with marked stridor and respiratory embarrassment. A stenosed subglottic area was found on rigid bronchoscopy. Anterior cricoid split was performed to relieve the obstruction. He is asymptomatic post operatively.
Haemophilus influenzae meningitis in Malaysia

Hussain IH, Sofiah A, Ong LC, Choo KE, Musa MN, Teh KH, et al.

Pediatr Infect Dis J, 1998 Sep;17(9 Suppl):S189-90.
PMID: 9781759

To determine the pattern of postneonatal childhood meningitis in Malaysia.
Production, structure and morphology of exopolysaccharides yielded by submerged fermentation of Antrodia cinnamomea

Chen L, Wang Z, Zhang B, Ge M, Ng H, Niu Y, et al.

Carbohydr Polym, 2019 Feb 01;205:271-278.
PMID: 30446105 DOI: 10.1016/j.carbpol.2018.10.070

Carbon and nitrogen sources in culture medium of Antrodia cinnamomea were optimized to eliminate the interference of exterior macromolecules on exopolysaccharide (EPS) yield by submerged fermentation. The results suggested that culture medium containing 50 g/L of glucose and 20 g/L of yeast extract as the optimal carbon and nitrogen sources could produce 1.03 g/L of exopolysaccharides. After purification, two heteropolysaccharides (AC-EPS1 and AC-EPS2) were obtained and characterized to provide the basic structure information. As the main component of the produced EPS, AC-EPS2 (accounting for 89.63%) was mainly composed of galactose (87.42%) with Mw (molecular weight) and R.M.S. (root-mean-square) radius of 1.18 × 105 g/mol and 25.3 nm, respectively. Furthermore, the spherical and flexible chain morphologies of EPS were observed in different solvents by TEM. The structural and morphological information of purified EPS were significant for further study on their structure-activity relationship and related applications.
Multistage optimizations of slow pyrolysis synthesis of biochar from palm oil sludge for adsorption of lead

Lee XJ, Lee LY, Hiew BYZ, Gan S, Thangalazhy-Gopakumar S, Kiat Ng H

Bioresour Technol, 2017 Dec;245(Pt A):944-953.
PMID: 28946195 DOI: 10.1016/j.biortech.2017.08.175

This research investigated the removal of lead (Pb(2+)) by a novel biochar derived from palm oil sludge (POS-char) by slow pyrolysis. Multistage optimizations with central composite design were carried out to firstly optimize pyrolysis parameters to produce the best POS-char for Pb(2+) removal and secondly to optimize adsorption conditions for the highest removal of Pb(2+). The optimum pyrolysis parameters were nitrogen flowrateof30mLmin(-1), heating rateof10°Cmin(-1), temperatureof500°C and timeof30min. The optimum Pb(2+) adsorption conditions were concentrationof200mgL(-1), timeof60min, dosageof0.3g and pH of 3.02. The various functional groups within POS-char played a vital role in Pb(2+) uptake. Regeneration was demonstrated to be feasible using hydrochloric acid. Adsorption equilibrium was best described by Freundlich model. At low concentration range, adsorption kinetic obeyed pseudo-first-order model, but at high concentration range, it followed pseudo-second-order model. Overall, the results highlighted that POS-char is an effective adsorbent for Pb(2+) removal.

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