Browse publications by year: 2003

  1. Lim CP, Quek SS, Peh KK
    J Pharm Biomed Anal, 2003 Feb 05;31(1):159-68.
    PMID: 12560060
    This paper investigates the use of a neural-network-based intelligent learning system for the prediction of drug release profiles. An experimental study in transdermal iontophoresis (TI) is employed to evaluate the applicability of a particular neural network (NN) model, i.e. the Gaussian mixture model (GMM), in modeling and predicting drug release profiles. A number of tests are systematically designed using the face-centered central composite design (CCD) approach to examine the effects of various process variables simultaneously during the iontophoresis process. The GMM is then applied to model and predict the drug release profiles based on the data samples collected from the experiments. The GMM results are compared with those from multiple regression models. In addition, the bootstrap method is used to assess the reliability of the network predictions by estimating confidence intervals associated with the results. The results demonstrate that the combination of the face-centered CCD and GMM can be employed as a useful intelligent tool for the prediction of time-series profiles in pharmaceutical and biomedical experiments.
    MeSH terms: Administration, Cutaneous; Algorithms; Artificial Intelligence; Delayed-Action Preparations*; Diffusion; Pharmaceutical Preparations/administration & dosage*; Electrodes; Iontophoresis*; Models, Theoretical; Normal Distribution
  2. Jumaat BH, Dahalan A, Mohamad M
    Am J Ophthalmol, 2003 Feb;135(2):254-6.
    PMID: 12566045
    PURPOSE: To report a case of choroidal osteoma presenting with massive subretinal hemorrhage not associated with choroidal neovascularisation (CNV).

    DESIGN: Case report.

    METHODS: An 18-year-old man presented with sudden loss of vision in the right eye following competitive swimming. He was found to have a massive subretinal hemorrhage involving the macula.

    RESULTS: Following resolution of the hemorrhage, the patient was found to have an underlying choroidal osteoma. There was no evidence of choroidal neovascularisation clinically and angiographically. He regained his normal vision.

    CONCLUSIONS: Choroidal osteoma presenting with massive subretinal hemorrhage not associated with underlying choroidal neovascularization need not result in poor visual outcome.

    MeSH terms: Adolescent; Blindness/etiology; Choroid Neoplasms/complications*; Choroid Neoplasms/diagnosis; Fluorescein Angiography; Humans; Male; Osteoma/complications*; Osteoma/diagnosis; Retinal Hemorrhage/diagnosis; Retinal Hemorrhage/etiology*; Tomography, X-Ray Computed; Visual Acuity
  3. Arumainathan U, Kumar M, Raman R
    Trop Doct, 2003 Jan;33(1):31.
    PMID: 12568517
    MeSH terms: Biopsy, Needle/standards*; Developing Countries; Humans; Otorhinolaryngologic Neoplasms/pathology*; Sensitivity and Specificity
  4. Mak KH, Chia KS, Kark JD, Chua T, Tan C, Foong BH, et al.
    Eur Heart J, 2003 Jan;24(2):151-60.
    PMID: 12573272
    AIMS: We compare the myocardial infarction (MI) event and mortality rates among Chinese, Malay and Indian residents of Singapore.

    METHODS: Residents, aged 20 to 64 years, with an MI event were identified from hospital discharge listings, postmortem reports, and the Registry of Births and Deaths. All pathology laboratories flagged patients with elevated creatine phosphokinase (CPK) levels. Modified MONICA (multinational monitoring of trends and determinants in cardiovascular disease) criteria were used for determining MI events.

    RESULTS: From 1991 to 1999, 12 481 MI events were identified. Chinese patients were older and less likely to have typical symptoms or previous MI. Malays had the highest peak CPK level. Among all three ethnic groups, MI event and age-adjusted case-fatality rates declined. Compared with Chinese, MI event rates were >2-fold and >3-fold higher, and age-standardized coronary mortality rates were 2.4 and 3.0 higher times for Malays and Indians, respectively. Malays have the highest 3.1-year case-fatality, with an adjusted hazard ratio of 1.26 (95% confidence interval, 1.14 to 1.38) compared with Chinese.

    CONCLUSION: We found strong ethnic differences in MI event, case-fatality and coronary mortality rates among the three ethnic groups in Singapore. While Indians have the greatest MI event rates, Malays have the highest case-fatality.

    MeSH terms: Adult; China/ethnology; Female; Follow-Up Studies; Humans; India/ethnology; Malaysia/ethnology; Male; Middle Aged; Myocardial Infarction/ethnology*; Myocardial Infarction/mortality; Singapore/epidemiology; Survival Rate; Survival Analysis; Age Distribution
  5. Yapp DT, Yap SY
    J Ethnopharmacol, 2003 Mar;85(1):145-50.
    PMID: 12576213
    Malaria remains a global problem in the light of chloroquine-resistant strains of Plasmodium falciparum. New compounds are needed for the development of novel antimalarial drugs. Seed, leaf, and fruit skin extracts of Lansium domesticum, a common fruit tree in South-East Asia, are used by indigenous tribes in Sabah, Malaysia for treating malaria. The skin and aqueous leaf extracts of the tree were found to reduce parasite populations of the drug sensitive strain (3D7) and the chloroquine-resistant strain (T9) of P. falciparum equally well. The skin extracts were also found to interrupt the lifecycle of the parasite. The data reported here indicate that extracts of L. domesticum are a potential source for compounds with activity towards chloroquine-resistant strains of P. falciparum.
    MeSH terms: Animals; Antimalarials/pharmacology*; Chloroquine/pharmacology; Drug Resistance; Fruit/chemistry; Humans; Life Cycle Stages/drug effects; Plant Extracts/pharmacology; Plasmodium falciparum/drug effects*; Plant Leaves/chemistry; Meliaceae*; In Vitro Techniques
  6. Rahmah N, Lim BH, Azian H, Ramelah TS, Rohana AR
    Trop Med Int Health, 2003 Feb;8(2):158-63.
    PMID: 12581442
    Brugian filariasis infects 13 million people in Asia. The routine prevalence survey method using night thick blood smear is not sensitive enough to reflect the actual infection prevalence. In 1997-2001, only three microfilaraemic cases (of 5601 individuals screened; 0.05%) were reported in Pasir Mas, a district in Kelantan (Malaysia), which shares a border with Thailand. We therefore investigated the infection prevalence in this district by employing a sensitive and specific serological assay (Brugia-Elisa). This test is based on detection of specific IgG4 antibody against a Brugia malayi recombinant antigen. A total of 5138 children, aged 7-12 years, from 16 primary schools, were tested. Eighteen pupils in eight schools, located in five subdistricts, tested positive, giving an overall prevalence rate of 0.35%. Infection in these children is significant as they represent more recent cases. These subdistricts should be included in the national filariasis elimination programme.
    MeSH terms: Animals; Antibodies, Helminth/blood*; Antigens, Helminth*; Child; Elephantiasis, Filarial/diagnosis; Elephantiasis, Filarial/epidemiology*; Enzyme-Linked Immunosorbent Assay/methods; Female; Humans; Malaysia/epidemiology; Male; Sensitivity and Specificity; Prevalence; Brugia malayi/immunology; Brugia malayi/isolation & purification*
  7. Solomon T, Ni H, Beasley DW, Ekkelenkamp M, Cardosa MJ, Barrett AD
    J Virol, 2003 Mar;77(5):3091-8.
    PMID: 12584335
    Since it emerged in Japan in the 1870s, Japanese encephalitis has spread across Asia and has become the most important cause of epidemic encephalitis worldwide. Four genotypes of Japanese encephalitis virus (JEV) are presently recognized (representatives of genotypes I to III have been fully sequenced), but its origin is not known. We have determined the complete nucleotide and amino acid sequence of a genotype IV Indonesian isolate (JKT6468) which represents the oldest lineage, compared it with other fully sequenced genomes, and examined the geographical distribution of all known isolates. JKT6468 was the least similar, with nucleotide divergence ranging from 17.4 to 19.6% and amino acid divergence ranging from 4.7 to 6.5%. It included an unusual series of amino acids at the carboxy terminus of the core protein unlike that seen in other JEV strains. Three signature amino acids in the envelope protein (including E327 Leu-->Thr/Ser on the exposed lateral surface of the putative receptor binding domain) distinguished genotype IV strains from more recent genotypes. Analysis of all 290 JEV isolates for which sequence data are available showed that the Indonesia-Malaysia region has all genotypes of JEV circulating, whereas only more recent genotypes circulate in other areas (P < 0.0001). These results suggest that JEV originated from its ancestral virus in the Indonesia-Malaysia region and evolved there into the different genotypes which then spread across Asia. Our data, together with recent evidence on the origins of other emerging viruses, including dengue virus and Nipah virus, imply that tropical southeast Asia may be an important zone for emerging pathogens.
    MeSH terms: Amino Acid Sequence; Animals; Asia, Southeastern; Encephalitis Virus, Japanese/classification; Encephalitis Virus, Japanese/genetics*; Encephalitis Virus, Japanese/pathogenicity; Encephalitis, Japanese/physiopathology; Encephalitis, Japanese/virology*; Genotype; Humans; Models, Molecular; Molecular Sequence Data; Phylogeny*; Virulence; Sequence Analysis, DNA; Evolution, Molecular*; Mice
  8. Lai CK, De Guia TS, Kim YY, Kuo SH, Mukhopadhyay A, Soriano JB, et al.
    J Allergy Clin Immunol, 2003 Feb;111(2):263-8.
    PMID: 12589343
    Few data on asthma management are available for the Asia-Pacific region.
    MeSH terms: Adrenal Cortex Hormones/therapeutic use; Adult; Asia; Asthma/drug therapy*; Asthma/physiopathology; Bronchodilator Agents/therapeutic use; Child; Child, Preschool; Data Collection; Female; Humans; Male; Middle Aged; Pacific Islands; Theophylline/therapeutic use
  9. Gan SH, Ismail R, Wan Adnan WA, Wan Z
    Clin Chim Acta, 2003 Mar;329(1-2):61-8.
    PMID: 12589966 DOI: 10.1016/s0009-8981(03)00019-6
    BACKGROUND: Hair roots provide a useful alternative to blood as a source of DNA for genotyping. Besides simple and non-invasive collections, the DNA extraction step is also easy to perform and is fast. The aim of our study is to determine if hair roots can be used to genotype all of the common CYP2D6 alleles for routine screening purposes.

    METHOD: The study complies with the Declaration of Helsinki. After obtaining informed consents, both blood and hair samples were collected from 92 patients for genotyping of the CYP2D6 gene. PCR was used to detect the following mutations: CYP2D6*1, *3, *4, *5, *9, *10, *17 and duplication gene. The results were compared where hair roots and blood were used as templates for DNA respectively.

    RESULTS: When blood was used as a source of DNA for genotyping, all of the investigated CYP2D6 alleles were successfully amplified. However, with hair roots, the genes with the larger fragment sizes: CYP2D6*5 and the duplication gene could not be amplified and the bands of other alleles investigated were faint when visualized under UV light.

    CONCLUSIONS: DNA extraction from hair roots and leucocytes yielded similar results but the DNA extracted from hair roots did not allow successful amplification of the longer genes such as the CYP2D6*5 and the duplication gene.
    MeSH terms: Alleles; DNA/chemistry*; Electrophoresis, Agar Gel; Genotype; Hair/chemistry*; Humans; Isoenzymes/genetics; Leukocytes/chemistry; Cytochrome P-450 CYP2D6/genetics*; Reverse Transcriptase Polymerase Chain Reaction; Gene Duplication
  10. Wong HS, Morad Z
    Transplant Proc, 2003 Feb;35(1):230-1.
    PMID: 12591376
    MeSH terms: Adult; Creatinine/blood; Dose-Response Relationship, Drug; Female; Humans; Immunosuppressive Agents/blood; Immunosuppressive Agents/pharmacokinetics*; Immunosuppressive Agents/therapeutic use; Malaysia; Male; Retrospective Studies; Tissue Donors; Cyclosporine/blood; Cyclosporine/pharmacokinetics*; Cyclosporine/therapeutic use; Drug Monitoring/methods; Living Donors
  11. Ooi MH, Wong SC, Clear D, Perera D, Krishnan S, Preston T, et al.
    Clin Infect Dis, 2003 Mar 1;36(5):550-9.
    PMID: 12594634
    We report the virological and clinical features of 8 children who presented with adenovirus-associated acute flaccid paralysis (AFP) during an epidemic of enterovirus type 71 (EV71)-associated hand-foot-and-mouth disease (HFMD) in Sarawak, Malaysia, in 1997. Neutralization tests and phylogenetic analysis revealed adenovirus type 21 (Ad21), although DNA restriction digests suggested that this virus was different from the prototype Ad21. Four children had upper-limb monoparesis, 2 had lower-limb monoparesis (one of whom had changes in the anterior spinal cord noted on magnetic resonance imaging), and 2 had flaccid paraparesis. At follow-up, 4 children were noted to have made full recoveries and 3 had residual flaccid weakness and wasting. Neurophysiological investigation revealed a mixture of axonal and demyelinating features in motor and sensory nerves, with denervation. These findings suggest that Ad21 might cause AFP by anterior horn cell damage or neuropathy of the brachial or lumbosacral plexus. The occurrence of these unusual adenovirus infections during an outbreak of EV71-associated HFMD suggests that an interaction between the 2 viruses may have occurred.
    MeSH terms: Acute Disease; Adenoviridae/classification; Adenoviridae/immunology; Adenoviridae/isolation & purification*; Adenoviridae Infections/complications*; Adenoviridae Infections/immunology; Adenoviridae Infections/virology; Disease Outbreaks*; Female; Hand, Foot and Mouth Disease/complications; Hand, Foot and Mouth Disease/epidemiology*; Humans; Infant; Malaysia/epidemiology; Male; Paraplegia/complications; Paraplegia/immunology; Paraplegia/virology*
  12. Kanaheswari Y
    J Paediatr Child Health, 2003 Mar;39(2):118-23.
    PMID: 12603800 DOI: 10.1046/j.1440-1754.2003.00105.x
    OBJECTIVES: To estimate the prevalence of nocturnal enuresis in primary school children in Malaysia and to determine the factors associated with primary nocturnal enuresis.

    METHODS: This was a cross-sectional survey. A total of 3371 self-administered questionnaires were distributed to parents of children aged 7, 9 and 12 years attending four primary schools in the city. The ICD-10 definition of enuresis was used.

    RESULTS: From an overall response rate of 73.8%, nocturnal enuresis was reported in 200 children (8%), primary nocturnal enuresis in 156 children (6.2%) and secondary nocturnal enuresis in 44 children (1.8%). Fifty-three percent of those with primary enuresis had a positive family history, and 54% had two or more wet nights per week. Eighty-seven percent had not sought any form of treatment despite 74% admitting to being embarrassed. Using logistic regression analysis, only three factors were significant predictors of primary nocturnal enuresis. These were: (i) younger age (P < 0.001); (ii) male sex (P < 0.033); and (iii) Indian ethnic group (P < 0.044) compared to Chinese.

    CONCLUSION: The prevalence of nocturnal enuresis in urban-dwelling Malaysian children is similar to that reported from Korea and Taiwan but appears to be lower than that reported from developed countries. Predictive factors associated with primary nocturnal enuresis included lower age group, male sex and Indian ethnicity.
    MeSH terms: Child; Child, Preschool; Cross-Sectional Studies; Enuresis/diagnosis; Enuresis/epidemiology*; Female; Health Surveys; Humans; Malaysia/epidemiology; Male; Probability; Surveys and Questionnaires; Risk Factors; Incidence; Logistic Models; Age Distribution; Sex Distribution
  13. Monirith I, Ueno D, Takahashi S, Nakata H, Sudaryanto A, Subramanian A, et al.
    Mar Pollut Bull, 2003 Mar;46(3):281-300.
    PMID: 12604061
    Contamination of persistent organochlorines (OCs) such as PCBs (polychlorinated biphenyls), DDT and its metabolites (DDTs), HCH (hexachlorocyclohexane) isomers (HCHs), chlordane compounds (CHLs), and HCB (hexachlorobenzene) were examined in mussels collected from coastal waters of Asian countries such as Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Far East Russia, Singapore, and Vietnam in 1994, 1997, 1998, 1999, and 2001 to elucidate the contamination status, distribution and possible pollution sources and to assess the risks on aquatic organisms and human. OCs were detected in all mussels collected from all the sampling sites investigated. Considerable residue levels of p,p(')-DDT and alpha-HCH were found in mussels and the concentrations of DDTs and HCHs found in mussels from Asian developing countries were higher than those in developed nations suggesting present usage of DDTs and HCHs along the coastal waters of Asian developing countries. On the other hand, lower concentrations of PCBs detected in mussels from Asian developing countries than those in developed countries indicate that PCBs contamination in mussels is strongly related to industrial and activities. To our knowledge, this is a first comprehensive report on monitoring OCs pollution in the Asia-Pacific region.
    MeSH terms: Animals; Asia; Lindane/adverse effects*; Lindane/analysis; DDT/adverse effects*; DDT/analysis; Developing Countries*; Environmental Monitoring/methods*; Environmental Pollutants/adverse effects*; Environmental Pollutants/analysis; Industry; Insecticides/adverse effects*; Insecticides/analysis; Polychlorinated Biphenyls/adverse effects*; Polychlorinated Biphenyls/analysis; Risk Assessment; Bivalvia*
  14. Ong BB, Green M
    Am J Forensic Med Pathol, 2003 Mar;24(1):64-9.
    PMID: 12605001
    In a strict and conservative society like Malaysia, the number of cases of infanticide has continued to occur. The authors present two typical cases of infanticide in Malaysia. Case 1 concerned a body of a fully mature newborn fetus disposed in a rubbish bin. The head was traumatically amputated by the rubbish truck's compactor. The umbilical cord was still attached to the body, with no reddening around the insertion. The severed neck showed features consistent with post-mortem amputation. The significant finding was expanded crepitant lungs, which floated in water. The histology of the lungs showed expanded alveoli. It was concluded that the baby had been born alive, but no cause of death could be elicited. Case 2 concerned a decomposed mature newborn found in a scrub forest. The internal organs showed advanced putrefaction, the lungs being collapsed, congested, and hemorrhagic, typical of decomposed lungs. No conclusion could be made about the state of birth or the cause of death because of the putrefied state of the body. The two cases illustrate the typical cases and problems faced by pathologists locally and probably elsewhere in the world. Most of the bodies are found in a putrefied state. Pathologists have to ascertain not only maturity and live birth but also the cause of death, which may be very subtle or masked by putrefaction. The problems of diagnosis of live birth are discussed.
    MeSH terms: Amputation, Traumatic/pathology; Female; Head/pathology; Humans; Infant, Newborn; Infanticide*; Lung/pathology; Malaysia; Postmortem Changes; Pulmonary Alveoli/pathology
  15. Goldsmith CS, Whistler T, Rollin PE, Ksiazek TG, Rota PA, Bellini WJ, et al.
    Virus Res, 2003 Mar;92(1):89-98.
    PMID: 12606080
    Nipah virus, which was first recognized during an outbreak of encephalitis with high mortality in Peninsular Malaysia during 1998-1999, is most closely related to Hendra virus, another emergent paramyxovirus first recognized in Australia in 1994. We have studied the morphologic features of Nipah virus in infected Vero E6 cells and human brain by using standard and immunogold electron microscopy and ultrastructural in situ hybridization. Nipah virions are enveloped particles composed of a tangle of filamentous nucleocapsids and measured as large as 1900 nm in diameter. The nucleocapsids measured up to 1.67 microm in length and had the herringbone structure characteristic for paramyxoviruses. Cellular infection was associated with multinucleation, intracytoplasmic nucleocapsid inclusions (NCIs), and long cytoplasmic tubules. Previously undescribed for other members of the family Paramyxoviridae, infected cells also contained an inclusion formed of reticular structures. Ultrastructural ISH studies suggest these inclusions play an important role in the transcription process.
    MeSH terms: Animals; Brain/virology; Cercopithecus aethiops; Humans; RNA, Viral/genetics; RNA, Viral/metabolism; Vero Cells; Virus Replication; Microscopy, Immunoelectron; In Situ Hybridization; Paramyxovirinae/genetics; Paramyxovirinae/growth & development*; Paramyxovirinae/physiology*; Paramyxovirinae/ultrastructure; Paramyxoviridae Infections/virology; Encephalitis, Viral/virology; Virus Assembly; In Vitro Techniques
  16. Coetzee MP, Wingfield BD, Bloomer P, Ridley GS, Wingfield MJ
    Mycologia, 2003 Mar-Apr;95(2):285-93.
    PMID: 21156614
    Armillaria root rot is a serious disease, chiefly of woody plants, caused by many species of Armillaria that occur in temperate, tropical and subtropical regions of the world. Very little is known about Armillaria in South America and Southeast Asia, although Armillaria root rot is well known in these areas. In this study, we consider previously unidentified isolates collected from trees with symptoms of Armillaria root rot in Chile, Indonesia and Malaysia. In addition, isolates from basidiocarps resembling A. novae-zelandiae and A. limonea, originating from Chile and Argentina, respectively, were included in this study because their true identity has been uncertain. All isolates in this study were compared, based on their similarity in ITS sequences with previously sequenced Armillaria species, and their phylogenetic relationship with species from the Southern Hemisphere was considered. ITS sequence data for Armillaria also were compared with those available at GenBank. Parsimony and distance analyses were conducted to determine the phylogenetic relationships between the unknown isolates and the species that showed high ITS sequence similarity. In addition, IGS-1 sequence data were obtained for some of the species to validate the trees obtained from the ITS data set. Results of this study showed that the ITS sequences of the isolates obtained from basidiocarps resembling A. novae-zelandiae are most similar to those for this species. ITS sequences for isolates from Indonesia and Malaysia had the highest similarity to A. novae-zelandiae but were phylogenetically separated from this species. Isolates from Chile, for which basidiocarps were not found, were similar in their ITS and IGS-1 sequences to the isolate from Argentina that resembled A. limonea. These isolates, however, had the highest ITS and IGS-1 sequence similarity to authentic isolates of A. luteobubalina and were phylogenetically more closely related to this species than to A. limonea.
    MeSH terms: Argentina; Chile; Indonesia; Malaysia; Phylogeny; Wood; Plant Roots; Databases, Nucleic Acid; Fruiting Bodies, Fungal; Armillaria
  17. Zain AM, Syedsahiljamalulail S
    Malays J Nutr, 2003 Mar;9(1):19-29.
    PMID: 22692529
    Stress is a common phenomenon. Every individual experiences it. There are many ways of combating stress. Stress is necessary for preparation against challenging situations and danger. It is necessary to have stress before a test so that we are prepared. For instance, stress actually motivates students to prepare for examination but excessive stress can lead to poor performance. This study evaluates the effect of a commercial essence of chicken (CEC) on the various parameters related to stress and cognition of human volunteers. CEC is produced by a hot-water extraction process from chicken meat under high pressure condition. It contains concentrated amounts of proteins, amino acids and peptides such as carnosine compared to homemade traditional chicken soup. Due to the unique extraction process, it has been postulated that readily absorbed amino acids and bioactive peptides are present in CEC. In this experiment, we evaluated the effect of CEC in comparison with a placebo and carageenan on a group of stressed medical students before their examinations. Students were divided into three groups at random and given either CEC, placebo or a carageenan drink daily for two weeks. Before and after the two weeks, the students were given a series of tests to assess their mental and physical well-being as well as attention and memory. The tests were the general health questionnaire (GHQ), SF36, digit span, construction of figures, 3-min memory test, comprehension and mental arithmetic. The students who ingested essence of chicken fared significantly better than the other two groups of students. The ability of essence of chicken to control anxiety by distraction and promoting attention and memory is discussed.
  18. Ismail A, Cheah SF
    Malays J Nutr, 2003 Mar;9(1):31-9.
    PMID: 22692530
    As consumer interest in organically grown vegetables is increasing in Malaysia, there is a need to answer whether the vegetables are more nutritious than those conventionally grown. This study investigates commercially available vegetables grown organically and conventionally, purchased from retailers to analyse β-carotene, vitamin C and riboflavin contents. Five types of green vegetables were selected, namely Chinese mustard (sawi) (Brassica juncea), Chinese kale (kai-lan) (Brassica alboglabra), lettuce (daun salad) (Lactuca sativa), spinach (bayam putih) (Amaranthus viridis) and swamp cabbage (kangkung) (Ipomoea aquatica). For vitamin analysis, a reverse-phase high performance liquid chromatography was used to identify and quantify β -carotene, vitamin C and riboflavin. The findings showed that not all of the organically grown vegetables were higher in vitamins than that conventionally grown. This study found that only swamp cabbage grown organically was highest in β -carotene, vitamin C and riboflavin contents among the entire samples studied. The various nutrients in organically grown vegetables need to be analysed for the generation of a database on nutritional value which is important for future research.
  19. Subramaniam V, Adenan MI, Ahmad AR, Sahdan R
    Malays J Nutr, 2003 Mar;9(1):41-51.
    PMID: 22692531 MyJurnal
    The antioxidant activity of two edible medicinal plants commonly used in Malaysian traditional medicine i.e. Piper sarmentosum (kadok) and Morinda elliptica (mengkudu) were tested for antioxidant activity. The methanolic leave extracts of kadok and mengkudu, at 250ug/ml, were tested using the Xanthine/Xanthine Oxidase (X/XOD) Superoxide Scavenging assay. Both extracts showed high superoxide scavenging assay, 88% and 80% respectively compared to superoxide dismutase (SOD) standard. The crude extracts were further fractionated using column chromatography and tested for superoxide scavenging activity, to obtain antioxidant active fractions. Two active fractions were obtained from kadok, PsFr6-71.3%, PsFr7-71.3%, and one active fraction from mengkudu, MeFr3-86.6%. These active fractions were compared against 14 phenolic compound standards. After a series of HPLC analysis of samples and standards, a natural antioxidant compound was identified in kadok and mengkudu i.e. Naringenin (4',5,7-Trihydroxyflavanone) with 75.7% superoxide scavenging activity. Naringenin is a highly potent natural antioxidant that has been reported in the raw materials of larch and grapefruit extracts. Thus, kadok and mengkudu which contain Naringenin, could be used as antioxidant dietary supplements.
  20. Singh R
    Malays J Nutr, 2003 Mar;9(1):53-74.
    PMID: 22692532 MyJurnal
    Major sporting events in Malaysia are commonly staged in hot environments where the average daytime temperature is generally in the range of 29 to 31°C with the average relative humidity ranging from 80 to 95%. Exercise capacity and exercise performance are reduced when the ambient temperature is high and it has major implications for competitors as well as for spectators and officials. Prolonged exercise leads to progressive water and electrolyte loss from the body as sweat is secreted to promote heat loss. The rate of sweating depends on many factors and increases in proportion to work rate and environmental temperature and humidity. Sweat rates are highly variable and can exceed 2L.h-1 for prolonged periods in high heat. Since dehydration will impair exercise capacity and can pose a risk to health, the intake of fluid during exercise to offset sweat losses is important. Carbohydrate-electrolyte fluid ingestion during exercise has the dual role of providing a source of carbohydrate fuel to supplement the body's limited stores and of supplying water and electrolytes to replace the losses incurred by sweating. The composition of the drinks to be taken will be influenced by the relative importance of the need to supply fuel and water which, in turn depends on the intensity and duration of exercise activity, the ambient temperature, and humidity. Carbohydrate-electrolyte solutions appear to be more effective in improving performance than plain water. There is no advantage to fluid intake during exercise of less than 30-minute duration. Complete restoration of fluid balance after exercise is an important part of the recovery process and becomes even more important in hot, humid conditions. If a second bout of exercise has to be performed after a relatively short interval, the speed of rehydration becomes of crucial importance. Rehydration after exercise requires not only replacement of volume losses, but also replacement of some electrolytes, primarily sodium. Studies show that rehydration after exercise can be achieved only if sweat electrolyte losses as well as water are replaced. Drinks with low sodium content are ineffective at rehydration and they will only reduce the stimulus to drink. Addition of smalls amounts of carbohydrate to the rehydrating drinks may improve the rate of intestinal uptake of sodium and water and will improve palatability. The volume of the rehydration beverage consumed should be greater than the volume of sweat lost to provide the ongoing obligatory urine losses. Palatability of the beverage is a major issue when a large volume of fluid has to be consumed.
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