Displaying all 17 publications

Abstract:
Sort:
  1. Koh KC, Wong MH
    Malays Fam Physician, 2011;6(1):29-31.
    PMID: 25606217 MyJurnal
    A 19-year-old man presented with sudden onset of right eye ptosis, diplopia and giddiness. He had no previous medical illnesses with negative history of exertional dyspnoea, epistaxis, haemoptysis, palpitations, chest pain and chronic cough. Examination revealed central cyanosis, digital clubbing, polycythaemia, partial ptosis of right eye, diplopia on right gaze and dilated right pupil. Examination of the chest revealed pectus excavatum but no cardiac murmurs were heard. Investigations revealed a solitary right pulmonary arteriovenous malformation with two feeder vessels which were successfully embolized surgically.
  2. Wong MH, Sockalingam S, Zain A
    Int J Rheum Dis, 2011 Aug;14(3):e38-41.
    PMID: 21816012 DOI: 10.1111/j.1756-185X.2011.01602.x
    We report a 57-year-old woman with a 20-year history of hepatitis B presenting with progressive proximal lower limb weakness for the previous 1 month. Previous medical history included a pericardial and pleural effusion, of which no cause was found and pulmonary tuberculosis which has been adequately treated. Examination revealed multiple telangiactasia over face and nail beds and bilateral proximal lower limb weakness of power 4/5. Biochemical investigation revealed a raised erythrocyte sedimentation rate of 36 mm/h, elevated creatinine kinase levels (14,363 IU/L) and raised liver enzymes (alanine aminotransferase 445 IU/L, aspartate aminotransferase 606 IU/L) with high hepatitis B virus DNA (1,021,158 copies/mL). Nerve conduction tests and muscle biopsy were consistent with polymyositis. She received entacavir for hepatitis B treatment. Despite treatment with entacavir for 10 weeks, her weakness persisted and prednisolone was added. Upon commencement of prednisolone, her symptoms and biochemical profiles returned to normal.
  3. Wong MH, Chee KH, Azman W
    Singapore Med J, 2009 Oct;50(10):e362-4.
    PMID: 19907876
    A 40-year-old Malay woman presented with increasing lethargy, palpitation and shortness of breath, 17 years after a mitral and aortic valve replacement. A Starr-Edwards prosthetic valve replaced the mitral valve, and a Bjork-Shiley prosthetic valve replaced the aortic valve. Biochemical parameters demonstrated intravascular haemolysis, as evidenced by haemoglobin 7.8 g/dL, reticulocyte count 8.4%, lactate dehydrogenase 2,057 IU/L and low haptoglobulin levels (less than 6 mg/dL). Transoesophageal echocardiography revealed a paravalvular leakage over the mitral valve. The haemoglobin levels remained persistently low despite frequent blood transfusions. She successfully underwent a second mitral valve replacement. Her anaemia resolved subsequently.
  4. Wong MH, Lim LF, Ahmad FB, Assim ZB
    Asian Pac J Trop Biomed, 2014 May;4(5):386-92.
    PMID: 25182724 DOI: 10.12980/APJTB.4.2014C1129
    To investigate antioxidant and antimicrobial activities of two plant species, Litsea elliptica (L. elliptica) and Litsea resinosa (L. resinosa).
  5. Chai LK, Wong MH, Bruun Hansen HC
    J Environ Manage, 2013 Aug 15;125:28-32.
    PMID: 23632002 DOI: 10.1016/j.jenvman.2013.04.005
    The insecticide chlorpyrifos is extensively used in the humid tropics for insect control on crops and soils. Chlorpyrifos degradation and mineralization was studied under laboratory conditions to characterize the critical factors controlling the degradation and mineralization in three humid tropical soils from Malaysia. The degradation was fastest in moist soils (t1/2 53.3-77.0 days), compared to dry (t1/2 49.5-120 days) and wet soils (t1/2 63.0-124 days). Degradation increased markedly with temperature with activation energies of 29.0-76.5 kJ mol(-1). Abiotic degradation which is important for chlorpyrifos degradation in sub-soils containing less soil microbial populations resulted in t½ of 173-257 days. Higher chlorpyrifos dosages (5-fold) which are often applied in the tropics due to severe insects infestations caused degradation and mineralization rates to decrease by 2-fold. The mineralization rates were more sensitive to the chlorpyrifos application rates reflecting that degradation of metabolites is rate limiting and the toxic effects of some of the metabolites produced. Despite that chlorpyrifos is frequently used and often in larger amounts on tropical soils compared with temperate soils, higher temperature, moderate moisture and high activity of soil microorganisms will stimulate degradation and mineralization.
  6. Chai LK, Wong MH, Mohd-Tahir N, Hansen HC
    Chemosphere, 2010 Apr;79(4):434-40.
    PMID: 20189217 DOI: 10.1016/j.chemosphere.2010.01.046
    Acephate is poorly sorbed to soil, thus the risk of leaching to the aquatic environment is high if it is not quickly degraded. The effect of soil moisture, temperature, microbial activity and application rate on acephate degradation has been studied in three Malaysian soils to examine and identify critical variables determining its degradation and mineralization kinetics. First-order kinetics could be used to describe degradation in all cases (r(2)>0.91). Acephate degraded faster in air-dry (t((1/2)) 9-11 d) and field capacity (t((1/2)) 10-16d) soils than in the wet soils (t((1/2)) 32-77 d). The activation energy of degradation was in the range 17-28 kJ mol(-1) and significantly higher for the soil with higher pH and lower clay and iron oxide contents. Soil sterilization caused a 3- to 10-fold decrease in degradation rates compared to non-sterile soils (t((1/2)) 53-116 d) demonstrating that acephate degradation is mainly governed by microbial processes. At 5-fold increase in application rates (25 microg g(-1)), half-life increased slightly (t((1/2)) 13-19 d) or was unaffected. Half-life from acephate mineralization was similar to those from degradation but much longer at the 5-fold increase in acephate application rates (t((1/2)) 41-96 d) demonstrating that degradation of metabolites is rate limiting. Thus, application of acephate should be restricted or avoided during wet seasons with heavy rainfall and flooded soil as in paddy cultivation. Sandy soils with low microbial activity are more prone to acephate leaching than clay soils rich in humic matter.
  7. Lim KS, Wo SW, Wong MH, Tan CT
    Epilepsy Behav, 2013 Apr;27(1):130-4.
    PMID: 23416283 DOI: 10.1016/j.yebeh.2012.12.034
    Studies on the impact of epilepsy on employment have been extensively performed in European and some Asian countries but not in Southeast Asia such as Malaysia, a country with a robust economy, low unemployment rate, and minimal social security benefits for the unemployed. This study aims to determine the impact of epilepsy on employment in Malaysia.
  8. Wan Md Adnan WA, Zaharan NL, Wong MH, Lim SK
    PLoS One, 2014;9(12):e114262.
    PMID: 25546434 DOI: 10.1371/journal.pone.0114262
    Chronic kidney disease is an emerging problem in the majority Muslim countries. Despite the uncertainties of the risks involved, some Muslim patients undergoing chronic haemodialysis choose to observe intermittent fasting during the month of Ramadan. This study aims to investigate the effect of Ramadan fasting in haemodialysis patients residing in a tropical climate country.
  9. Lim KS, Hills MD, Choo WY, Wong MH, Wu C, Tan CT
    Epilepsy Behav, 2013 Feb;26(2):158-61.
    PMID: 23314303 DOI: 10.1016/j.yebeh.2012.12.001
    Students' attitudes toward epilepsy have been studied in several countries, but none of the studies used a quantitative scale. We aimed to determine the validity and reliability of the Public Attitudes Toward Epilepsy (PATE) scale in a homogenous population consisting of secondary and tertiary students in Malaysia and to quantify their attitudes toward epilepsy, using a web-based survey.
  10. Lim KS, Hills MD, Choo WY, Wong MH, Wu C, Tan CT
    Epilepsy Res, 2013 Oct;106(3):433-9.
    PMID: 23886655 DOI: 10.1016/j.eplepsyres.2013.06.014
    INTRODUCTION: There is a lack of study comparing the attitudes toward epilepsy between the teachers and general population, teachers and students, using a similar quantitative scale.
    METHODS: This study was performed in one primary and one secondary school in Kuala Lumpur, Malaysia, using the Public Attitudes Toward Epilepsy (PATE) scale.
    RESULTS: A total of 186 teachers aged 39.6±10.4 years completed the questionnaire. The mean scores in both personal and general domains of PATE scale were significantly better in the teachers, comparing to the scores in the secondary and college students reported in previous study (Lim et al., 2013; p<0.001 and <0.05, respectively). The mean scores in personal domain was significantly better in the teachers, comparing to the general population reported by Lim et al. (2012; p<0.001). This hold true when comparing teachers with general population with tertiary education, suggesting that the better attitude is specific to the job, rather than tertiary education generally. Subanalysis showed that the attitudes of teachers were significantly better than the general population and the students related to employment and social life, but were equally negative on issues directly related to education, such as placing children with epilepsy in regular classes.
    CONCLUSION: Teachers had more positive attitudes toward epilepsy as compared with the general population with tertiary education. Attitude to epilepsy may differ specific to types of work.
  11. Lew TTS, Wong MH, Kwak SY, Sinclair R, Koman VB, Strano MS
    Small, 2018 Nov;14(44):e1802086.
    PMID: 30191658 DOI: 10.1002/smll.201802086
    The ability to control the subcellular localization of nanoparticles within living plants offers unique advantages for targeted biomolecule delivery and enables important applications in plant bioengineering. However, the mechanism of nanoparticle transport past plant biological membranes is poorly understood. Here, a mechanistic study of nanoparticle cellular uptake into plant protoplasts is presented. An experimentally validated mathematical model of lipid exchange envelope penetration mechanism for protoplasts, which predicts that the subcellular distribution of nanoparticles in plant cells is dictated by the particle size and the magnitude of the zeta potential, is advanced. The mechanism is completely generic, describing nanoparticles ranging from quantum dots, gold and silica nanoparticles, nanoceria, and single-walled carbon nanotubes (SWNTs). In addition, the use of imaging flow cytometry to investigate the influence of protoplasts' morphological characteristics on nanoparticle uptake efficiency is demonstrated. Using DNA-wrapped SWNTs as model nanoparticles, it is found that glycerolipids, the predominant lipids in chloroplast membranes, exhibit stronger lipid-nanoparticle interaction than phospholipids, the major constituent in protoplast membrane. This work can guide the rational design of nanoparticles for targeted delivery into specific compartments within plant cells without the use of chemical or mechanical aid, potentially enabling various plant engineering applications.
  12. Ong MP, Sam IC, Azwa H, Mohd Zakaria IE, Kamarulzaman A, Wong MH, et al.
    J Infect, 2010 Nov;61(5):440-2.
    PMID: 20708031 DOI: 10.1016/j.jinf.2010.08.001
  13. Yaiw KC, Hyatt A, Vandriel R, Crameri SG, Eaton B, Wong MH, et al.
    Arch Virol, 2008;153(5):865-75.
    PMID: 18330496 DOI: 10.1007/s00705-008-0059-0
    Tioman virus (TioPV) and Menangle virus (MenPV) are two antigenically and genetically related paramyxoviruses (genus: Rubulavirus, family: Paramyxoviridae) isolated from Peninsular Malaysia (2001) and Australia (1997), respectively. Both viruses are potential zoonotic agents. In the present study, the infectivity, growth kinetics, morphology and morphogenesis of these two paramyxoviruses in a human neuronal cell (SK-N-SH) line were investigated. Sub-confluent SK-N-SH cells were infected with TioPV and MenPV at similar multiplicity of infection. These cells were examined by conventional and immunoelectron microscopy, and virus titres in the supernatants were assayed. Syncytia were observed for both infections in SK-N-SH cells and were more pronounced during the early stages of TioPV infection. The TioPV titre increased consistently (10(1)) every 12 h after infection. In MenPV-infected cells, cellular material was frequently observed within budding virions, and microfilaments and microtubules were abundant. Viral budding was common, and extracellular MenPVs tended to be more pleomorphic compared to TioPVs, which appeared to be more spherical in appearance. The MenPV cytoplasmic viral inclusion appeared to be comparatively smaller, loose and interspersed with randomly scattered circle-like particles, whereas huge tubule-like cytoplasmic inclusions were observed in TioPV-infected cells. Both viruses also displayed different cellular pathology in the SK-N-SH cells. The intracellular ultrastructural characteristics of these two viruses in infected neuronal cells may allow them to be differentiated by electron microscopy.
  14. Cheng Z, Li HH, Wang HS, Zhu XM, Sthiannopkao S, Kim KW, et al.
    Environ Res, 2016 Oct;150:423-30.
    PMID: 27372065 DOI: 10.1016/j.envres.2016.06.011
    Phthalate esters are used in a wide variety of consumer products, and human exposure to this class of compounds is widespread. Nevertheless, studies on dietary exposure of human to phthalates are limited. In this study, to assess the daily intakes of phthalate esters and the possible adverse health impacts, different food samples were collected from three areas of Cambodia, one of the poorest countries in the world. The ∑phthalate ester concentrations in Kampong Cham, Kratie and Kandal provinces ranged from 0.05 to 2.34 (median 0.88) μgg(-1), 0.19-1.65 (median 0.86) μgg(-1) and 0.24-3.05 (median 0.59) μgg(-1) wet weight (ww), respectively. Di-2-Ethylhexyl phthalate (DEHP) and diisobutyl phthalate (DiBP) were the predominant compounds among all foodstuffs. The estimated daily intake (EDI) of phthalate esters for the general population in Kampong Cham, Kratie and Kandal was 34.3, 35.6 and 35.8μgkg(-1) bw d(-1), respectively. The dietary daily intake of DEHP, benzylbutyl phthalate (BBP) and di-n-butyl phthalate (DBP) in Kampong Cham, Kratie and Kandal were below the tolerable daily intakes (TDI) imposed by the European Food Safety Authority (EFSA) and reference doses (RfD) imposed by The United States Environmental Protection Agency (USEPA). Rice contributed the greatest quantity of DEHP to the daily intake in Cambodia so may deserve further exploration. To our knowledge, this is the first study to investigate the occurrence and the daily intakes of phthalate esters in Cambodia.
  15. Mazarji M, Bayero MT, Minkina T, Sushkova S, Mandzhieva S, Bauer TV, et al.
    Sci Total Environ, 2023 Jul 01;880:163330.
    PMID: 37023818 DOI: 10.1016/j.scitotenv.2023.163330
    Biochar can be used for soil remediation in environmentally beneficial manner, especially when combined with nanomaterials. After a decade of research, still, no comprehensive review was conducted on the effectiveness of biochar-based nanocomposites in controlling heavy metal immobilization at soil interfaces. In this paper, the recent progress in immobilizing heavy metals using biochar-based nanocomposite materials were reviewed and compared their efficacy against that of biochar alone. In details, an overview of results on the immobilization of Pb, Cd, Cu, Zn, Cr, and As was presented by different nanocomposites made by various biochars derived from kenaf bar, green tea, residual bark, cornstalk, wheat straw, sawdust, palm fiber, and bagasse. Biochar nanocomposite was found to be most effective when combined with metallic nanoparticles (Fe3O4 and FeS) and carbonaceous nanomaterials (graphene oxide and chitosan). This study also devoted special consideration to different remediation mechanisms by which the nanomaterials affect the effectiveness of the immobilization process. The effects of nanocomposites on soil characteristics related to pollution migration, phytotoxicity, and soil microbial composition were assessed. A future perspective on nanocomposites' use in contaminated soils was presented.
  16. Hashim JH, Radzi RS, Aljunid SM, Nur AM, Ismail A, Baguma D, et al.
    Sci Total Environ, 2013 Oct 1;463-464:1210-6.
    PMID: 23759330 DOI: 10.1016/j.scitotenv.2013.04.084
    Natural, inorganic arsenic contamination of groundwater threatens the health of more than 100 million people worldwide, including residents of the densely populated river deltas of South and Southeast Asia. Contaminated groundwater from tube wells in Cambodia was discovered in 2001 leading to the detection of the first cases of arsenicosis in 2006. The most affected area was the Kandal Province. The main objective of this study was to determine the prevalence of arsenicosis in Cambodia based on acceptable criteria, and to investigate the use of hair arsenic as a biomarker not only for arsenicosis-related signs but also for associated symptoms. A cross-sectional epidemiological study of 616 respondents from 3 purposely selected provinces within the Mekong River basin of Cambodia was conducted. The Kandal Province was chosen as a high arsenic-contaminated area, while the Kratie Province and Kampong Cham Province were chosen as moderate and low arsenic-contaminated areas, respectively. The most prevalent sign of arsenicosis was hypomelanosis with a prevalence of 14.5% among all respondents and 32.4% among respondents with a hair arsenic level of ≥1 μg/g. This was followed by hyperkeratosis, hyperpigmentation and mee's lines. Results also suggest a 1.0 μg/g hair arsenic level to be a practical cut off point for an indication of an arsenic contaminated individual. This hair arsenic level, together with the presence of one or more of the classical signs of arsenicosis, seems to be a practical criteria for a confirmed diagnosis. Based on these criteria, the overall prevalence of arsenicosis for all provinces was found to be 16.1%, with Kandal Province recording the highest prevalence of 35.5%. This prevalence is comparatively high when compared to that of other affected countries. The association between arsenicosis and the use of Chinese traditional medicine also needs further investigation.
  17. Thumboo J, Fong KY, Chng HH, Koh ET, Chia HP, Leong KH, et al.
    J Rheumatol, 1998 Jul;25(7):1299-304.
    PMID: 9676760
    OBJECTIVE: To determine the effects of ethnicity on disease manifestations in Oriental patients with systemic lupus erythematosus (SLE) and to describe the risk of developing renal or central nervous system (CNS) involvement with time.
    METHODS: A retrospective study of 472 patients with SLE seen at the only Rheumatology Unit in Singapore. The effect of ethnicity on selected disease manifestations at diagnosis was assessed after adjusting for demographic variables using multiple logistic regression. The probability of developing selected disease manifestations with time was determined using the Kaplan-Meier product limit method.
    RESULTS: At diagnosis, Malays had a higher risk of renal or CNS involvement than Chinese (OR 2.26, 95% CI 1.21 to 4.21, and OR 3.07, 95% CI 1.01 to 9.34, respectively), and Indians a lower risk of malar rash and a higher risk of oral ulcers than Chinese (OR 0.30, 95% CI 0.13 to 0.68, and OR 2.90, 95% CI 1.45 to 7.34, respectively). The prevalence of renal or CNS involvement in the entire cohort increased with time, reaching 75.6% (95% CI 66.1% to 85.0%) and 16.7% (95% CI 11.7% to 21.6%), respectively, after 18 years of disease.
    CONCLUSION: Ethnicity influenced disease manifestations at diagnosis in this cohort of Oriental patients with SLE. Renal or CNS involvement developed in previously unaffected patients up to 18 years after diagnosis, highlighting the need for continued vigilance in patients with lupus.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links