Displaying publications 1 - 20 of 168 in total

Abstract:
Sort:
  1. Rhanye Mac Guad, Wan Ahmad Hafiz Wan Md Adnan, Zamri Chik, Gan, Siew Hua
    MyJurnal
    Calcineurin inhibitors, cyclosporine and tacrolimus are increasingly becoming part of the standard immunosuppresant therapies for renaltransplanted patients in Malaysia. In this study, the clinical safety and efficacy of cyclosporine and tacrolimus in a Malaysian renal-transplanted population is compared. A fourteen-year retrospective review on all renal-transplanted patients (from September 1991 to September 2015) or patients being followed up at University Malaya Medical Centre (UMMC) on cyclosporine or tacrolimus regime was conducted. We collected the clinical and laboratory parameters at 3-month, 6-month, 7-month, 8-month, 9-month, 10-month, 11-month, 12- months, 2-year and 3-year following from transplantation for each drug. The mean cyclosporine and tacrolimus trough levels were within the recommended therapeutic ranges (189.16 ± 69.10 ng/ml and 7.84 ± 2.18 mg/day respectively). The mean low-density lipoprotein (LDL) was significantly higher at eleven months for tacrolimus compared to cyclosporine. Similarly, the mean total bilirubin level was significantly higher with cyclosporine as compared to tacrolimus between 3 – 9 months post transplantation but did not show any significant difference (p = 0.49). The overall monthly means of serum uric acid levels in patients were also similar, 380 ± 87 mg/dL (cyclosporine) and 390.96 ± 95.97 mg/dL (tacrolimus) (p = 0.49). The Kaplan-Meier survival rate is significantly longer (p = 0.03) with cyclosporine-based treatment as compared to tacrolimus. Overall, cyclosporine and tacrolimus did not show any significant difference in terms of safety and efficacy parameters among Malaysian renal-transplanted patients indicating that they may be used interchangeably.
  2. Yusof W, Gan SH
    Clin Chim Acta, 2009 May;403(1-2):105-9.
    PMID: 19361454 DOI: 10.1016/j.cca.2009.01.032
    CYP2A6 gene encodes the principal enzyme involved in the metabolism of many drugs including artesunate. We developed a simplified duplex nested PCR method for the detection of the CYP2A61B, CYP2A62, CYP2A64, CYP2A67, CYP2A68 and CYP2A69 variant alleles highly prevalent among Malaysian population.
  3. Rao PV, Gan SH
    Curr Drug Metab, 2015;16(5):371-5.
    PMID: 25429672 DOI: 10.2174/1389200215666141125120215
    Nanotechnology is a field encompassing nanostructures, nanomaterials and nanoparticles, which are of increasing importance to researchers and industrial players alike. Nanotechnology addresses the construction and consumption of substances and devices on the nanometer scale. Nanomedicine is a new field that combines nanotechnology with medicine to boost human health care. Nanomedicine is an interdisciplinary field that includes various areas of biology, chemistry, physics and engineering. The most important problems related to diabetes management, such as self-monitoring of blood glucose levels and insulin injections, can now be conquered due to progress in nanomedicine, which offers glucose nanosensors, the layer-by-layer technique, carbon nanotubes, quantum dots, oral insulins, microspheres, artificial pancreases and nanopumps. In this review, the key methodological and scientific characteristics of nanomedicine related to diabetes treatment, glucose monitoring and insulin administration are discussed.
  4. Loo KW, Gan SH
    Gene, 2014 Jul 15;545(1):1-4.
    PMID: 24815047 DOI: 10.1016/j.gene.2014.05.016
    The Kelantanese Malays who resided in the remote northeastern regions of the Malay Peninsula in the Kelantan state are believed to have a unique genetic signature. The objective of this review is to analyze the populational sub-structure of the Kelantanese Malays from historical, genetic and linguistic perspectives. Historical data suggest that the Semang were composed of the Jahai, Bateq and Kensiu sub-tribes, whereas the Senoi were composed of only the Temiar sub-tribe. The Mendriq sub-tribe is believed to be the first group of aborigines to land in Kelantan. Subsequently, genetic analysis showed that the Kelantanese Malays are an independent clade at the base of the phylogenetic tree and contain genetic material similar to that of the Semang, specifically the Jahai and the Kensiu sub-tribes. The genetic data are supported by the fact that the Aslian language, a branch of the Austroasiatic languages that is widely spoken by the Semang, was potentially transmitted through agricultural activities. However, the potential limitation of this mini-review is the lack of primary reliable sources covering the historical, linguistic and genetic features of the Kelantanese Malays.
  5. Loo KW, Gan SH
    Int J Stroke, 2013 Jun;8(4):273-5.
    PMID: 22974070 DOI: 10.1111/j.1747-4949.2012.00884.x
    In the Lao People's Democratic Republic (Laos), stroke is ranked as the third leading cause of death, with a 9·01% mortality rate. To date, neither the prevalence nor the incidence of stroke has been recorded in Laos. This omission may be attributed to a lack of awareness among Laotians of the signs and symptoms of stroke, incomplete data, or insufficient database recording. The only risk factor for stroke that has been studied extensively is cigarette smoking; studies have found that smokers have twice the risk of stroke. Unfortunately, smoking is increasing among youths, adults, and even healthcare professionals. The Southeast Asia Tobacco Control Alliance stated that 42% of hospitalized stroke patients are smokers. Laos is one of the least developed countries in the world, and the country has only one fully trained neurologist for the growing number of stroke cases. The Laos government should seek help from international bodies, such as the World Health Organization, to monitor and rehabilitate stroke patients and prevent stroke occurrence and recurrence.
  6. Loo KW, Gan SH
    Int J Stroke, 2013 Aug;8(6):475-8.
    PMID: 22973861 DOI: 10.1111/j.1747-4949.2012.00868.x
    In Cambodia, stroke is not ranked among the top 10 leading causes of death, but infectious disease are among the top three leading causes of death. This finding could be attributed to a lack of awareness among Cambodians of the signs and symptoms of stroke or to poor reporting, incomplete data, lack of neurologists and neurosurgeons, or low accessibility to the hospitals. The only study of stroke in Cambodia is the Prevalence of Non-Communicable Disease Risk Factors in Cambodia survey, which identified several stroke-related risk factors in the population. Tobacco chewing or smoking is the main risk factor for stroke in Cambodia. Traditional therapies, such as oyt pleung (moxibustion) and jup (cupping), are widely practiced for stroke rehabilitation. In Cambodia, there are few neurologists and few important equipment, such as magnetic resonance imaging machines and computed tomography scanners. The Cambodian government should cooperate with the World Health Organization and the United Nations Children's Fund to attract foreign expertise and technologies to treat stroke patients.
  7. Loo KW, Gan SH
    Int J Stroke, 2013 Feb;8(2):131-4.
    PMID: 22568853 DOI: 10.1111/j.1747-4949.2012.00806.x
    Based on disability-adjusted life-years, stroke is the second leading cause of death and among the top five diseases with the greatest burden. Although two community-based studies have been conducted to determine the prevalence of stroke in the Philippines, the incidence has not been nationally recorded to date. The prevalence ranged from 1·9% to 6·59%, and 'Wiihabilitation', a rehabilitation stroke therapy, is widely practiced. A clinical trial for stroke rehabilitation using the Chinese Medicine NeuroAid®, which consists of several herbs, is ongoing in many hospitals across the Philippines. Due to their ready availability, phytomedicines are widely used, especially in the rural areas, for the treatment of hypertension, diabetes mellitus, and hypercholesterolemia, which are predisposing factors for stroke in the Philippines. Due to the increasing number of stroke cases annually, the government of the Philippines should emphasize primary and secondary prevention strategies.
  8. Loo KW, Gan SH
    Int J Stroke, 2012 Feb;7(2):165-7.
    PMID: 22264370 DOI: 10.1111/j.1747-4949.2011.00767.x
    Stroke is one of the top five leading causes of death and one of the top 10 causes for hospitalization in Malaysia. Stroke is also in the top five diseases with the greatest burden of disease, based on disability-adjusted life years. However, prospective studies on stroke in Malaysia are limited. To date, neither the prevalence of stroke nor its incidence nationally has been recorded. Hypertension is the major risk factor for stroke. The mean age of stroke patients in Malaysia is between 54.5 and 62.6 years. Traditional medicine is commonly practiced. With the increasing number of stroke cases annually, more government and nongovernment organizations should be involved in primary and secondary prevention strategies.
  9. Abubakar MB, Gan SH
    Oncology, 2016;91(1):3-12.
    PMID: 27233906 DOI: 10.1159/000446437
    The advent of advanced molecular targeted therapy has resulted in improved prognoses for patients with advanced malignancies. However, despite the significant success and specificity of this advocated targeted therapy, significant on- and off-target adverse effects and inter-individual variability in treatment responses have been reported. The interpatient variability in drug response has been suggested to be partly due to variations in patient genomes. Therefore, the identification of genetic biomarkers by conducting pharmacogenetics studies can help predict patient responses to targeted therapy and may serve as a basis for individualized treatment. In this review, both clinically established and potential molecular targets are highlighted. Overall, current literature suggests that individualization of targeted therapy is promising; however, integrating the clinical benefits of identified biomarkers into clinical practice for personalized medicine remains a major challenge, and further studies to validate these markers and identify novel therapeutic approaches are needed.
  10. Shaik MM, Gan SH
    Biomed Res Int, 2015;2015:469529.
    PMID: 25815319 DOI: 10.1155/2015/469529
    Migraine is the most common form of headache disorder globally. The etiology of migraine is multifactorial, with genetic components and environmental interactions considered to be the main causal factors. Some researchers postulate that deficits in mitochondrial energy reserves can cause migraine or an increase in homocysteine levels can lead to migraine attacks; therefore, vitamins could play a vital role in migraine prevention. For instance, riboflavin influences mitochondrial dysfunction and prevents migraine. Genes such as flavoenzyme 5,10-methylenetetrahydrofolate reductase (MTHFR), especially the C677T variant, have been associated with elevated plasma levels of homocysteine and migraine with aura. Homocysteine catalyzation requires the presence of vitamins B6, B12, and folic acid, which can decrease the severity of migraine with aura, making these vitamins potentially useful prophylactic agents for treating migraine with aura. Menstrual migraine, on the other hand, is associated with increased prostaglandin (PG) levels in the endometrium, indicating a role for vitamin E, which is an anti-PG. Vitamin C can also be used as a scavenger of reactive oxygen species for treating neurogenic inflammation in migraine patients. This paper reviews possible therapies based on vitamin supplementation for migraine prophylaxis, focusing on migraine with aura and menstrual migraine.
  11. Shaik MM, Gan SH
    Indian J Pharmacol, 2013 Mar-Apr;45(2):159-67.
    PMID: 23716893 DOI: 10.4103/0253-7613.108303
    Hyperhomocysteinemia and vitamins B(6), B(9), and B(12) deficiencies usually result in various neurological, vascular, ocular, renal, and pulmonary abnormalities. However, to date, there are no simultaneous detection methods available for determining homocysteine, vitamins B(6), B(9), and B(12) levels in various biological fluids. In this study, we aim to develop a new validated simultaneous detection method for all four compounds to save both cost and time of analysis.
  12. Rao PV, Gan SH
    PMID: 24817901 DOI: 10.1155/2014/642942
    Cinnamon (Cinnamomum zeylanicum, and Cinnamon cassia), the eternal tree of tropical medicine, belongs to the Lauraceae family. Cinnamon is one of the most important spices used daily by people all over the world. Cinnamon primarily contains vital oils and other derivatives, such as cinnamaldehyde, cinnamic acid, and cinnamate. In addition to being an antioxidant, anti-inflammatory, antidiabetic, antimicrobial, anticancer, lipid-lowering, and cardiovascular-disease-lowering compound, cinnamon has also been reported to have activities against neurological disorders, such as Parkinson's and Alzheimer's diseases. This review illustrates the pharmacological prospective of cinnamon and its use in daily life.
  13. Loo KW, Griffiths LR, Gan SH
    J Diabetes, 2014 Sep;6(5):447.
    PMID: 24645716 DOI: 10.1111/1753-0407.12151
  14. Abubakar MB, Wei K, Gan SH
    Pharmacogenet Genomics, 2014 Dec;24(12):575-81.
    PMID: 25203739 DOI: 10.1097/FPC.0000000000000092
    Breast cancer is a common cause of cancer mortality among women. Several genetic factors have been implicated in its development. Current treatment guidelines for estrogen receptor-positive breast cancer recommend that anastrozole [or any of the other two aromatase inhibitors (letrozole and exemestane)] is used as an alternative to tamoxifen or following several years of tamoxifen treatment. Nevertheless, this approach is still associated with many challenges, ranging from the recurrence of breast cancer to considerable interindividual variability in the tolerability of anastrozole, which may cause adverse effects, such as musculoskeletal symptoms, and lead to the withdrawal of many patients from treatment. Variabilities in the genes encoding the drug target (aromatase) or its metabolizing enzymes (CYP3A and UGT1A) contribute toward the interindividual variability in anastrozole's pharmacokinetics and/or pharmacodynamics. This paper reviews the role of genetic polymorphisms of CYP19A1, CYP3A4, and UGT1A4 in the responses of female hormone receptor-positive postmenopausal breast cancer patients to anastrozole. Many reviews in the literature have suggested that the study of functional polymorphisms and investigation of relevant genetic markers may provide valuable information in predicting responses to anastrozole in terms of its therapeutic and adverse effects. Nevertheless, more studies are required before the knowledge of its pharmacogenomics can be applied to the individualization of treatment to ensure that patients receive the maximum benefits. Therefore, future analyses, including but not limited to genome-wide association studies, are encouraged to address some of the gray areas in the pharmacogenomics of anastrozole therapy in postmenopausal breast cancer cases; this will help in providing guidance for future pharmacogenomics protocols when anastrozole is utilized in patients' management.
  15. Tan KL, Ankathil R, Gan SH
    J Chromatogr B Analyt Technol Biomed Life Sci, 2011 Nov 15;879(30):3583-91.
    PMID: 22000961 DOI: 10.1016/j.jchromb.2011.09.048
    We developed a simple and sensitive method for the simultaneous detection of imatinib mesylate (IM) and its active metabolite, N-desmethyl imatinib (M1), in human serum samples. Separation was successfully achieved using an Agilent(®) ZORBAX Eclipse plus C(18) reversed phase column (50 mm × 2.1 mm, i.d.; 1.8 μm) under isocratic mobile phase conditions consisting of acetonitrile: 0.02 M potassium dihydrogen phosphate with 0.2% triethylamine at pH 3 (25:75, v/v) and ultra-violet detection was achieved at 235 nm. Extraction of the target compounds was completed using 100% cold acetonitrile. Good linearities (r(2)>0.99) for both IM and M1 were achieved for the concentration ranges of 50-1800 ng/mL and 50-360 ng/mL, respectively. The detection limits were 20 ng/mL and 10 ng/mL for M1 and IM, respectively. The intra- and inter-day precisions were less than 1% with percent recoveries of more than 90%. The method was successfully applied to calculate the pharmacokinetic parameters of chronic myeloid leukemia patients receiving imatinib. The method is suitable to be routinely applied for determination of IM and M1 in serum.
  16. Loo KW, Griffiths LR, Gan SH
    BMC Med Genet, 2012 May 17;13:34.
    PMID: 22594584 DOI: 10.1186/1471-2350-13-34
    BACKGROUND: Hyperhomocysteinemia as a consequence of the MTHFR 677 C > T variant is associated with cardiovascular disease and stroke. Another factor that can potentially contribute to these disorders is a depleted nitric oxide level, which can be due to the presence of eNOS +894 G > T and eNOS -786 T > C variants that make an individual more susceptible to endothelial dysfunction. A number of genotyping methods have been developed to investigate these variants. However, simultaneous detection methods using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis are still lacking. In this study, a novel multiplex PCR-RFLP method for the simultaneous detection of MTHFR 677 C > T and eNOS +894 G > T and eNOS -786 T > C variants was developed. A total of 114 healthy Malay subjects were recruited. The MTHFR 677 C > T and eNOS +894 G > T and eNOS -786 T > C variants were genotyped using the novel multiplex PCR-RFLP and confirmed by DNA sequencing as well as snpBLAST. Allele frequencies of MTHFR 677 C > T and eNOS +894 G > T and eNOS -786 T > C were calculated using the Hardy Weinberg equation.

    METHODS: The 114 healthy volunteers were recruited for this study, and their DNA was extracted. Primer pair was designed using Primer 3 Software version 0.4.0 and validated against the BLAST database. The primer specificity, functionality and annealing temperature were tested using uniplex PCR methods that were later combined into a single multiplex PCR. Restriction Fragment Length Polymorphism (RFLP) was performed in three separate tubes followed by agarose gel electrophoresis. PCR product residual was purified and sent for DNA sequencing.

    RESULTS: The allele frequencies for MTHFR 677 C > T were 0.89 (C allele) and 0.11 (T allele); for eNOS +894 G > T, the allele frequencies were 0.58 (G allele) and 0.43 (T allele); and for eNOS -786 T > C, the allele frequencies were 0.87 (T allele) and 0.13 (C allele).

    CONCLUSIONS: Our PCR-RFLP method is a simple, cost-effective and time-saving method. It can be used to successfully genotype subjects for the MTHFR 677 C > T and eNOS +894 G > T and eNOS -786 T > C variants simultaneously with 100% concordance from DNA sequencing data. This method can be routinely used for rapid investigation of the MTHFR 677 C > T and eNOS +894 G > T and eNOS -786 T > C variants.

  17. Mijanur Rahman M, Gan SH, Khalil MI
    PMID: 24876885 DOI: 10.1155/2014/958721
    Honey is the only insect-derived natural product with therapeutic, traditional, spiritual, nutritional, cosmetic, and industrial value. In addition to having excellent nutritional value, honey is a good source of physiologically active natural compounds, such as polyphenols. Unfortunately, there are very few current research projects investigating the nootropic and neuropharmacological effects of honey, and these are still in their early stages. Raw honey possesses nootropic effects, such as memory-enhancing effects, as well as neuropharmacological activities, such as anxiolytic, antinociceptive, anticonvulsant, and antidepressant activities. Research suggests that the polyphenol constituents of honey can quench biological reactive oxygen species and counter oxidative stress while restoring the cellular antioxidant defense system. Honey polyphenols are also directly involved in apoptotic activities while attenuating microglia-induced neuroinflammation. Honey polyphenols are useful in improving memory deficits and can act at the molecular level. Therefore, the ultimate biochemical impact of honey on specific neurodegenerative diseases, apoptosis, necrosis, neuroinflammation, synaptic plasticity, and behavior-modulating neural circuitry should be evaluated with appropriate mechanistic approaches using biochemical and molecular tools.
  18. Shaik MM, Hassan NB, Tan HL, Gan SH
    Biomed Res Int, 2015;2015:523717.
    PMID: 25632394 DOI: 10.1155/2015/523717
    Disability caused by migraine may be one of the main causes of burden contributing to poor quality of life (QOL) among migraine patients. Thus, this study aimed to measure QOL among migraine sufferers in comparison with healthy controls.
  19. Chua YA, Abdullah WZ, Yusof Z, Gan SH
    Biomed Res Int, 2014;2014:316310.
    PMID: 24790995 DOI: 10.1155/2014/316310
    The vitamin K epoxide reductase complex 1 gene (VKORC1) is commonly assessed to predict warfarin sensitivity. In this study, a new nested allele-specific multiplex polymerase chain reaction (PCR) method that can simultaneously identify single nucleotide polymorphisms (SNPs) at VKORC1 381, 861, 5808, and 9041 for haplotype analysis was developed and validated. Extracted DNA was amplified in the first PCR DNA, which was optimized by investigating the effects of varying the primer concentrations, annealing temperature, magnesium chloride concentration, enzyme concentration, and the amount of DNA template. The amplification products produced from the first round of PCR were used as templates for a second PCR amplification in which both mutant and wild-type primers were added in separate PCR tubes, followed by optimization in a similar manner. The final PCR products were resolved by agarose gel electrophoresis and further analysed by using a VKORC1 genealogic tree to infer patient haplotypes. Fifty patients were identified to have H1H1, one had H1H2, one had H1H7, 31 had either H1H7 or H1H9, one had H1H9, eight had H7H7, and one had H8H9 haplotypes. This is the first method that is able to infer VKORC1 haplotypes using only conventional PCR methods.
  20. Moniruzzaman M, Sulaiman SA, Azlan SA, Gan SH
    Molecules, 2013;18(12):14694-710.
    PMID: 24287998 DOI: 10.3390/molecules181214694
    Honey is a good source of several important chemical compounds and antioxidants and is harvested throughout the year. However, no study has determined how their contents change over the years. The aim of the present research was to investigate the changes in the phenolics, flavonoids and antioxidant properties, as well as other physicochemical properties, of Malaysian acacia honey collected during different months during a two year period. The DPPH (1,1-diphenyl-2-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) methods were used to determine the total antioxidant activity of the honey samples. Generally, honey samples collected in the beginning and the middle of the year tended to have higher sugar content, which may be attributed to its high acidic nature and low moisture content. There was a gradual increase in the phenolic content of the acacia honey samples collected between September 2010 and December 2010. The honey sample collected at the beginning of the year (January) showed the highest color intensity and was dark amber in color. It also contained the highest concentration of phenolic compounds (341.67 ± 2.94 mg(gallic acid)/kg), the highest flavonoid content (113.06 ± 6.18 mg(catechin)/kg) and the highest percentage of DPPH inhibition and the highest FRAP value, confirming its high antioxidant potential. There was a positive correlation between DPPH and total phenolic content, suggesting that phenolic compounds are the strongest contributing factor to the radical scavenging activity of Malaysian acacia honeys. Overall, our results indicated that there were significant seasonal variations in the antioxidant potentials of honey over the two year period and the time of honey collection affects its physicochemical properties. Therefore, acacia honey from Malaysia should ideally be collected during the dry season, particularly in the months of January, May and June.
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links