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  1. Cheng, L.H., Nur Halawiah, H., Lai, B.N, Yong, H.M., Ang, S.L.
    MyJurnal
    Konjac glucomannan (KGM) was treated with or without sonication and/or hydrochloric acid (HCl).
    Hydrolysis effects on KGM were studied for properties such as degree of hydrolysis, fluidity, molecular mass, and creep properties. The degree of hydrolysis for sonicated KGM and acid treated KGM were not significantly different. However, the combination treatment of acid hydrolysis and sonication was found effective in yielding a smaller molecular weight fraction of KGM and solution with higher fluidity. From the creep analysis, KGM treated with combination treatment exhibited the highest compliance among samples tested. In general, ultrasound mediated acid hydrolysis was found to be a promising technique in degrading high molecular weight biopolymer. This could be attributed to a localized high temperature and high shear forces generated during cavitation that facilitated the endothermic acid hydrolysis.
  2. Nadarajan V, Shanmugam H, Sthaneshwar P, Jayaranee S, Sultan KS, Ang C, et al.
    Int J Lab Hematol, 2011 Oct;33(5):463-70.
    PMID: 21501392 DOI: 10.1111/j.1751-553X.2011.01309.x
    INTRODUCTION:
    The glucose-6-phosphate dehydrogenase (G6PD) fluorescent spot test (FST) is a useful screening test for G6PD deficiency, but is unable to detect heterozygote G6PD-deficient females. We sought to identify whether reporting intermediate fluorescence in addition to absent and bright fluorescence on FST would improve identification of mildly deficient female heterozygotes.

    METHODS:
    A total of 1266 cord blood samples (705 male, 561 female) were screened for G6PD deficiency using FST (in-house method) and a quantitative enzyme assay. Fluorescence intensity of the FST was graded as either absent, intermediate or normal. Samples identified as showing absent or intermediate fluorescence on FST were analysed for the presence of G6PD mutations using TaqMan@SNP genotyping assays and direct nucleotide sequencing.

    RESULTS:
    Of the 1266 samples, 87 samples were found to be intermediate or deficient by FST (49 deficient, 38 intermediate). Of the 49 deficient samples, 48 had G6PD enzyme activity of ≤ 9.5 U/g Hb and one sample had normal enzyme activity. All 38 intermediate samples were from females. Of these, 21 had G6PD activity of between 20% and 60%, and 17 samples showed normal G6PD activity. Twenty-seven of the 38 samples were available for mutation analysis of which 13 had normal G6PD activity. Eleven of the 13 samples with normal G6PD activity had identifiable G6PD mutations.

    CONCLUSION:
    Glucose-6-phosphate dehydrogenase heterozygote females cannot be identified by FST if fluorescence is reported as absent or present. Distinguishing samples with intermediate fluorescence from absent and bright fluorescence improves detection of heterozygote females with mild G6PD deficiency. Mutational studies confirmed that 85% of intermediate samples with normal enzyme activity had identifiable G6PD mutations.
  3. Abubakar MB, Abdullah WZ, Sulaiman SA, Suen AB
    Int J Mol Sci, 2012;13(11):15054-73.
    PMID: 23203111 DOI: 10.3390/ijms131115054
    Hematologic malignancies constitute about 9% of all new cases of cancers as reported via the GLOBOCAN series by International Agency for Research on Cancer (IARC) in 2008. So far, the conventional therapeutic and surgical approaches to cancer therapy have not been able to curtail the rising incidence of cancers, including hematological malignancies, worldwide. The last decade has witnessed great research interest in biological activities of phenolic compounds that include anticancer, anti-oxidation and anti-inflammation, among other things. A large number of anticancer agents combat cancer through cell cycle arrest, induction of apoptosis and differentiation, as well as through inhibition of cell growth and proliferation, or a combination of two or more of these mechanisms. Various phenolic compounds from different sources have been reported to be promising anticancer agents by acting through one of these mechanisms. Honey, which has a long history of human consumption both for medicinal and nutritional uses, contains a variety of phenolic compounds such as flavonoids, phenolic acids, coumarins and tannins. This paper presents a review on the molecular mechanisms of the anti-leukemic activity of various phenolic compounds on cell cycle, cell growth and proliferation and apoptosis, and it advocates that more studies should be conducted to determine the potential role of honey in both chemoprevention and chemotherapy in leukemia.
  4. Tan HJ, Ling WC, Chua AL, Lee SK
    Phytomedicine, 2021 Sep;90:153623.
    PMID: 34303263 DOI: 10.1016/j.phymed.2021.153623
    BACKGROUND: Concurrent use of epigallocatechin-3-gallate (EGCG) and medication may lead to botanical-drug interactions, subsequently therapeutic failure or drug toxicity. It has been reported that EGCG reduces plasma nadolol bioavailability in normotensive models. Nevertheless, evidence on the effects of EGCG on hypertensive model, and the possible underlying mechanism have not been elucidated.

    OBJECTIVES: This study aims (i) to investigate the effects of EGCG on nadolol pharmacokinetics (maximum plasma concentration, time to achieve maximum concentration, area under the time-plasma concentration curve, plasma half-life and total clearance) and subsequently its impact on blood pressure control; and (ii) to identify transcriptional regulatory roles of EGCG on the nadolol intestinal and hepatic drug-transporters in SHR.

    METHODS: Male SHR were pre-treated with a daily dose of EGCG (10 mg/kg body weight, i.g.) for 13 days. On day-14, a single dose of nadolol (10 mg/kg body weight) was given to the rats 30 min after the last dose of EGCG administration. Systolic blood pressure (SBP) was measured at 6-h and 22-h post-nadolol administration. Plasma and urinary nadolol concentrations were quantified using high-performance liquid chromatography, and pharmacokinetic parameters were analyzed by using non-compartmental analysis. Hepatic and ileal Oatp1a5, P-gp, and Oct1 mRNA expressions were determined by real-time PCR.

    RESULTS: SBP of SHR pre-treated with EGCG and received nadolol was significantly higher than those which were not pre-treated with EGCG but received nadolol. Pre-treatment of EGCG resulted in a marked reduction of plasma nadolol maximum concentration (Cmax) and area under the time-plasma concentration curve (AUC) by 53% and 51% compared to its control. The 14-day treatment with oral EGCG led to a significant downregulation of mRNA levels of ileal Oatp1a5, P-gp, and Oct1 genes by 4.03-, 8.01- and 4.03-fold; and hepatic P-gp, and Oct1 genes by 2.61- and 2.66-fold.

    CONCLUSION: These data concluded that exposure to EGCG could lead to reduced nadolol bioavailability and therefore, uncontrolled raised blood pressure and higher risks of cardiovascular events. Our data suggest that the reduced nadolol bioavailability is associated with the downregulation of ileal Oatp1a5 and Oct1 mRNA levels that subsequently lead to poor absorption of nadolol to the systemic circulation.

  5. Tou KAS, Rehman K, Ishak WMW, Zulfakar MH
    Drug Dev Ind Pharm, 2019 Sep;45(9):1451-1458.
    PMID: 31216907 DOI: 10.1080/03639045.2019.1628042
    Objective: The aim of this study was to develop a coenzyme Q10 nanoemulsion cream, characterize and to determine the influence of omega fatty acids on the delivery of coenzyme Q10 across model skin membrane via ex vivo and in silico techniques. Methods: Coenzyme Q10 nanoemulsion creams were prepared using natural edible oils such as linseed, evening primrose, and olive oil. Their mechanical features and ability to deliver CoQ10 across rat skin were characterized. Computational docking analysis was performed for in silico evaluation of CoQ10 and omega fatty acid interactions. Results: Linseed, evening primrose, and olive oils each produced nano-sized emulsion creams (343.93-409.86 nm) and exhibited excellent rheological features. The computerized docking studies showed favorable interactions between CoQ10 and omega fatty acids that could improve skin permeation. The three edible-oil nanoemulsion creams displayed higher ex vivo skin permeation and drug flux compared to the liquid-paraffin control cream. The linseed oil formulation displayed the highest skin permeation (3.97 ± 0.91 mg/cm2) and drug flux (0.19 ± 0.05 mg/cm2/h). Conclusion: CoQ10 loaded-linseed oil nanoemulsion cream displayed the highest skin permeation. The highest permeation showed by linseed oil nanoemulsion cream may be due to the presence of omega-3, -6, and -9 fatty acids which might serve as permeation enhancers. This indicated that the edible oil nanoemulsion creams have potential as drug vehicles that enhance CoQ10 delivery across skin.
  6. Wong AP, Kassab YW, Mohamed AL, Abdul Qader AM
    Pak J Pharm Sci, 2018 Jan;31(1):237-244.
    PMID: 29348109
    Hypertension is one of the major causes of morbidity and mortality. Worldwide, Hypertension is estimated to cause 7.5 million deaths, about 12.8% of the total of all deaths. This accounts for 57 million disability adjusted life years (DALYS) or 3.7% of total DALYS. This led WHO to set a target of 25% reduction in prevalence by 2025. To reach that, WHO has adopted non-conventional methods for the management of hypertension? Despite worldwide popularity of such non-conventional therapies, only small volume of evidence exists that supports its effectiveness. This review attempted to make a critical appraisal of the evidence, with the aim to (1) describe the therapeutic modalities frequently used, and (2) review the current level of evidence attributable to each modality. Databases from Cochrane Library, MEDLINE, PUBMED, and EMBASE were searched from 2005-2015. A total of 23 publications have been identified and selected. Out of these, 15 systematic reviews and/or meta-analysis of RCTs, 5 RCTs, 1 non-RCT, and 2 observational studies without control. Among those 23 publications, therapeutic modalities identified are: fish oil, qigong, yoga, coenzyme Q10, melatonin, meditation, vitamin D, vitamin C, monounsaturated fatty acids, dietary amino-acids, chiropractic, osteopathy, folate, inorganic nitrate, beetroot juice, beetroot bread, magnesium, and L-arginine. The followings were found to have weak or no evidence: fish oil, yoga, vitamin D, monounsaturated fatty acid, dietary amino-acids, and osteopathy. Those found to have significant reduction in blood pressure are: magnesium, qigong, melatonin, meditation, vitamin C, chiropractic, folate, inorganic nitrate, beetroot juice and L-arginine. Coenzyme Q10on the other hand, showed contradicting results were some studies found weak or no effect on blood pressure while others showed significant blood pressure reduction effect. By virtue of the research designs and methodologies, the evidence contributed from these studies is at level 1. Results from this review suggest that certain non-conventional therapies may be effective in treating hypertension and improving cardiac function and therefore considered as part of an evidence-based approach.
  7. Zalilah MS, Khor GL, Mirnalini K, Norimah AK, Ang M
    Singapore Med J, 2006 Jun;47(6):491-8.
    PMID: 16752017
    INTRODUCTION: Paediatric obesity is a public health concern worldwide as it can track into adulthood and increase the risk of adult morbidity and mortality. While the aetiology of obesity is multi-factorial, the roles of diet and physical activity are controversial. Thus, the purpose of this study was to report on the differences in energy intake, diet composition, time spent doing physical activity and energy expenditure among underweight (UW), normal weight (NW) and at-risk of overweight (OW) Malaysian adolescents (317 females and 301 males) aged 11-15 years.
    METHODS: This was a cross-sectional study with 6,555 adolescents measured for weights and heights for body mass index (BMI) categorisation. A total of 618 subjects were randomly selected from each BMI category according to gender. The subjects' dietary intake and physical activity were assessed using self-reported three-day food and activity records, respectively. Dietary intake components included total energy and macronutrient intakes. Energy expenditure was calculated as a sum of energy expended for basal metabolic rate and physical activity. Time spent (in minutes) in low, medium and high intensity activities was also calculated.
    RESULTS: The OW adolescents had the highest crude energy intake and energy expenditure. However, after adjusting for body weight, the OW subjects had the lowest energy intake and energy expenditure (p-value is less than 0.001). The study groups did not differ significantly in time spent for low, medium and high intensity activities. Macronutrient intakes differed significantly only among the girls where the OW group had the highest intakes compared to UW and NW groups (p-value is less than 0.05). All study groups had greater than 30 percent and less than 55 percent of energy intake from fat and carbohydrate, respectively.
    CONCLUSION: The data suggested that a combination of low energy expenditure adjusted for body weight and high dietary fat intake may be associated with overweight and obesity among adolescents. To prevent overweight and obesity among children and adolescents, strategies that address eating behaviours and physical activity are required. Various segments of the society must be involved in efforts to promote healthful dietary intakes and active lifestyle in children and adolescents.
  8. Low A, Chow RC, Ee Ling A, Khaliddin N
    Cureus, 2023 Jul;15(7):e41341.
    PMID: 37546106 DOI: 10.7759/cureus.41341
    A 72-year-old Chinese male presented with unilateral left eye panuveitis, then diagnosed as bilateral T-cell primary vitreoretinal lymphoma (T-PVRL) through chorioretinal biopsy and immunohistochemistry. No CNS nor systemic involvement was found at diagnosis. Despite initiating intravenous and intrathecal chemotherapy and intravitreal methotrexate, the disease eventually spread to the fellow eye with subsequent recurrence and systemic metastasis. To our knowledge, no cases of T-PVRL treated in a silicone-filled eye were reported in the literature. T- PVRL is exceedingly rare, with most PVRL being the malignant B-cell variant. This case highlights the challenges encountered throughout the treatment course of this aggressive entity, including the administration of intravitreal methotrexate in a silicone oil-filled eye. The poor overall survival rate and grim prognosis of T-PVRL are highlighted. Therefore, we recommend prompt tissue biopsy and immediate initiation of systemic chemotherapy and intravitreal methotrexate.
  9. Wong AP, Kalinovsky T, Niedzwiecki A, Rath M
    Exp Ther Med, 2015 Sep;10(3):1071-1073.
    PMID: 26622441
    Psoriasis is a chronic inflammatory skin disease characterized by thickened, silvery-scaled patches. There is currently no cure and treatments only attempt to reduce the severity of symptoms. This study reports the case of a 36-year-old female who presented to the clinic with severe psoriasis and had been treated with topical steroid cream for the past 14 years. After adherence to prescribed dietary changes for 6 months, including abundant intake of vegetables, minimal consumption of meat, and avoidance of junk food and sugar in food or drinks, as well as nutritional supplementation with Vitacor Plus, ProLysinC, VitaCforte and LysinC Drink mix, the patient experienced complete resolution of psoriatic patches on her body.
  10. Al-Haddad A, Arsheed NAA, Yee A, Kohli S
    Saudi Dent J, 2024 Jan;36(1):11-19.
    PMID: 38375394 DOI: 10.1016/j.sdentj.2023.10.004
    PURPOSE: This systematic review is aimed to evaluate in fixed prosthodontics treated teeth, the effect of the BOPT on periodontal health compared to the horizontal preparation technique using a chamfer finishing line or to the baseline.

    METHODS: The electronic databases Cochrane Central Library, PubMed, Scopus, and ScienceDirect were searched based on specific MeSH keywords. The Randomized controlled clinical trials (RCTs) and prospective clinical trials on BOPT printed in English up to July 2022 were selected. Screening, selection, and data extraction were done. The studies were assessed for risk of bias, and descriptive and meta-analyses were performed.

    RESULTS: Eight studies were included in the systematic review and only three RCTs were involved in the meta-analysis. Two RCTs were assessed as low risk while one has some concerns. were grouped as good, fair, and poor based on NOS. Three of the prospective studies were considered to be of good quality and one study was fair. The meta-analysis revealed no statistically significant difference in the effect of BOPT and chamfer preparation on periodontal health status and success rate (P > 0.05).

    CONCLUSIONS: Considering the limitation of this review, the BOPT is comparable to chamfer preparation and it resulted in an acceptable effect to maintain periodontal health with a high success rate. However, more evidence is required to support these findings.

  11. Iu Tong Lim, Avatar Singh Mohan Singh, Viji Ramasamy, Suhana Abdul Rahim, Ang Piao Piao, Irfan Mohamad
    MyJurnal
    Neurofibromatosis Type 1 (NF1), also known as von Recklinghausen’s disease is a multisystem genetic disorder that occurs with an incidence of 1 in 4000 live births. Plexiform nmeurofibroma (PN) is a rare important variant of NF1, seen in 5 to 15% of cases. We report a 7-year-old boy, without family history of neurofibromatosis presented with left neck swelling associated with multiple café au lait spots for one-year duration. Computed tomography of head and neck revealed an extensive soft tissue lesion involving the left parapharyngeal, carotid space and parotid space encasing the left internal and common carotid artery until its origin at the arch of aorta with erosion of the basiocciput. He underwent transcervical excision of the lesion, which was confirmed histopathologically as PN.
  12. Chelliah, Kanaga Kumari, Ang, Wee Chin, Abd Aziz Tajuddin, Arasaratnam, Shantini A., Suraya Aziz, Laila Suryani Elias
    MyJurnal
    Digital mammography has been progressively introduced in screening centers and the concern is to achieve an image of diagnostic value which would be able to detect early changes in the breast tissue. The aim of this study was to evaluate the image quality of mammograms using quantitative and qualitative methods of two FFDM systems with variations in breast thickness and anode/filter combination. This study was done from January to April 2008 with two FFDM systems; Siemens Mammomat NovationDR at Diagnostic Imaging Department, Hospital Kuala Lumpur and Hologic Lorad Selenia at Breast Clinic, National Cancer Society. A CIRS012A tissue equivalent breast phantom (4, 5 and 6 cm) thickness was used to obtain images in the craniocaudal plane with 26-32 kVp and a combination of molybdenum/molybdenum (Mo/Mo) and molybdenum/rhodium (Mo/Rh) anode/filter. For the qualitative evaluation, two independent radiologist with a minimum of five years experience was used to score the images. Wilcoxon Sign Rank Test showed that there are no significant differences (p > 0.05) in image quality between both the FFDM systems. Kappa analysis had a poor agreement between the scores given by the two radiologists. The quantitative analysis using Mann-Whitney test showed that there are significant differences (p < 0.05) between the SNR values of both FFDM systems. Although the qualitative evaluation was similar, the study showed that Lorad Selenia had a significantly superior SNR value, hence would be a better tool to detect early changes in the breast tissue. This study also demonstrated that a lower kVp is more suitable with molybdenum filter and as the breast thickness is increased rhodium filter with higher kVp displayed better quality images.
  13. Koh, Kwee Choy, Shanmugan Goonasakaren, Ng, Lam Kean, Chua, Yi Lin, Lee, Jia Ying, Alaric Ding Tian Ang
    MyJurnal
    Background: Medical schools are escalating changes
    to meet the need for doctors competent to work in the
    era of precision medicine. Information on the current
    level of awareness of precision medicine among medical
    students can help effect the necessary changes in the
    medical curriculum. A cross-sectional comparative
    study was done to assess the knowledge, attitude and
    perception toward the practice of precision medicine
    among junior and senior medical students in a medical
    school in Malaysia.

    Materials and Method: A survey instrument measuring
    attitude toward precision medicine, perceived
    knowledge of genomic testing concepts, and perception
    toward ethical consideration related to precision
    medicine, was distributed to junior and senior medical
    students. Comparisons were made between senior and
    junior medical students.

    Results: Only about one-third of the 356 respondents
    had heard of precision medicine although 92.7%
    expressed interest to learn more about precision
    medicine. Overall, junior and senior medical students
    had positive attitude toward the adoption of genomeguided
    prescribing and precision medicine but were
    uncomfortable with their knowledge of genomic testing
    concepts. Both junior and senior students were largely
    well grounded in their understanding of ethical issues
    related to precision medicine.

    Conclusions: Knowledge of precision medicine was low
    among junior and senior medical students. Although
    the students supported the use of precision medicine,
    they did not feel adequately prepared to apply genomics
    to clinical practice. Their perceptions on ethical issues
    related to precision medicine were sound. Seniority did
    not appear to influence the perceptions of the students.
  14. Laila Suryani Elias, Eng M, Ang W, Chelliah K, Abd Aziz Tajuddin, Arasaratnam S, et al.
    Sains Malaysiana, 2010;39:299-303.
    Mammography is used as a screening tool for early detection of breast cancer. However, the radiation dose used should be as low as possible to minimize any effects on asymptomatic woman while maintaining the diagnostic value of the image as mammography is done annually. This study was done to determine the optimum exposure parameter in exposure control mode (AEC) for two combinations of anode/filter which were molybdenum/molybdenum (Mo/Mo) and molybdenum/rhodium (Mo/Rh) using the Lorad Selenia digital mammography system at the Women’s Breast Clinic, National Cancer Society (NCS). A CIRS012A mammography research of phantom 4 cm thickness with 50% glandularity was exposed in the cranio-caudal projection. TLD 100H was used to measure the entrance surface air kerma (ESAK). The AGD values were then calculated from the ESAK values, incorporating three correction factors (g, c and s) according to Euref protocol. Image quality was evaluated using signal to noise ratio (SNR). Figure of Merit (FOM) which is the ratio of the square of SNR to the AGD shows that 30 kVp is the optimum exposure parameter for a 4 cm thickness phantom with the use of Mo/Rh and Mo/Mo anode/filter combination. Non-parametric Spearman correlation test showed a negative linear relationship between AGD and SNR with increasing tube voltage for both anode/filters.
    Keywords: Average glandular dose; CIRS012A phantom; exposure; full field digital mammography
    Study site: Women’s Breast Clinic, National Cancer Society (NCS), Kuala Lumpur, Malaysia
  15. Habiba U, Islam MS, Siddique TA, Afifi AM, Ang BC
    Carbohydr Polym, 2016 09 20;149:317-31.
    PMID: 27261756 DOI: 10.1016/j.carbpol.2016.04.127
    Chitosan/PVA/Na-titanate/TiO2 composite was synthesized by solution casting method. The composite was analyzed via Fourier Transform Infrared Spectroscopy, X-ray diffraction, Field Emission Scanning Electron Microscopy, Thermal gravimetric analysis and water stability test. Incorporation of Na-titanate shown decrease of crystallinity for chitosan but increase water stability. However, the composite structure was deteriorated with considerable weight loss in acidic medium. Two anionic dyes, methyl orange and congo red were used for the adsorption test. The adsorption behavior of the composites were described by pseudo-second-order kinetic model and Lagergren-first-order model for methyl orange and congo red, respectively. For methyl orange, adsorption was started with a promising decolorization rate. 99.9% of methyl orange dye was removed by the composite having higher weightage of chitosan and crystalline TiO2 phase. On the other hand, for the congo red the composite having higher chitosan and Na-titanate showed an efficient removal capacity of 95.76%. UV-vis results showed that the molecular backbone of methyl orange and congo red was almost destroyed when equilibrium was obtained, and the decolorization rate was reaching 100%. Kinetic study results showed that the photocatalytic degradation of methyl orange and congo red could be explained by Langmuir-Hinshelwood model. Thus, chitosan/PVA/Na-titanate/TiO2 possesses efficient adsorptivity and photocatalytic property for dye degradation.
  16. Nik Man NM, Hassan R, Ang CY, Abdullah AD, Mohd Radzi MA, Sulaiman SA
    Biomed Res Int, 2015;2015:307094.
    PMID: 26613081 DOI: 10.1155/2015/307094
    Complementary medicine using natural product as antitumor is on the rise. Much research has been performed on Tualang Honey and it was shown to have therapeutic potential in wound healing, and antimicrobial activity and be antiproliferative against several cancer models such as human osteosarcoma (HOS), human breast (MCF-7 and MDA-MB-231), and cervical (HeLa) cancer cell lines. To date, there was limited study on antileukemic properties of Tualang (Koompassia excelsa) Honey. The aim of this study was to evaluate the antileukemic effect of Tualang Honey on acute and chronic leukemia cell lines. Leukemia cell lines (K562 and MV4-11) and human mononuclear cell isolated from peripheral blood were grown in RPM1 1640 culture medium. The cells were incubated with increasing concentrations of Tualang Honey. After incubation, the evaluation of viability and apoptosis was performed. The morphological changes of leukemia cells were the presence of cytoplasmic blebs followed by apoptotic bodies and round shape of cells. IC50 against K562 and MV4-11 was determined. Tualang Honey gave 53.9% and 50.6% apoptosis activity on K562 and MV4-11, respectively, while on human mononuclear cell it was 37.4%. Tualang Honey has the apoptosis-inducing ability for acute and chronic myeloid leukemia (K562 and MV4-11) cell lines.
  17. Ang SH, Rambeli M, Thevarajah TM, Alias YB, Khor SM
    Biosens Bioelectron, 2016 Apr 15;78:187-93.
    PMID: 26606311 DOI: 10.1016/j.bios.2015.11.045
    We describe a gold nanoparticle-based sandwich immunoassay for the dual detection and measurement of hemoglobin A1c (HbA1c) and total hemoglobin in the whole blood (without pretreatment) in a single step for personalized medicine. The optimized antibody-functionalized gold nanoparticles immunoreact simultaneously with HbA1c and total hemoglobin to form a sandwich at distinctive test lines to transduce visible signals. The applicability of this method as a personal management tool was demonstrated by establishing a calibration curve to relate % HbA1c, a useful value for type 2 diabetes management, to the signal ratio of captured HbA1c to all other forms of hemoglobin. The platform showed excellent selectivity (100%) toward HbA1c at distinctive test lines when challenged with HbA0, glycated HbA0 and HbA2. The reproducibility of the measurement was good (6.02%) owing to the dual measurement of HbA1c and total hemoglobin. A blood sample stability test revealed that the quantitative measurement of % HbA1c was consistent and no false-positive results were detected. Also, this method distinguished the blood sample with elevated HbF from the normal samples and the variants. The findings of this study highlight the potential of a lateral flow immunosensor as a simple, inexpensive, consistent, and convenient strategy for the dual measurement of HbA1c and total Hb to provide useful % HbA1c values for better on-site diabetes care.
  18. Ang SS, Salleh AB, Chor AL, Normi YM, Tejo BA, Rahman MB
    Comput Biol Chem, 2015 Jun;56:19-29.
    PMID: 25766878 DOI: 10.1016/j.compbiolchem.2015.02.015
    Cytochrome P450s are a superfamily of heme monooxygenases which catalyze a wide range of biochemical reactions. The reactions involve the introduction of an oxygen atom into an inactivated carbon of a compound which is essential to produce an intermediate of a hydroxylated product. The diversity of chemical reactions catalyzed by cytochrome P450s has led to their increased demand in numerous industrial and biotechnology applications. A recent study showed that a gene sequence encoding a CYP was found in the genome of Bacillus lehensis G1, and this gene shared structural similarity with the bacterial vitamin D hydroxylase (Vdh) from Pseudonocardia autotrophica. The objectives of present study was to mine, for a novel CYP from a new isolate B. lehensis G1 alkaliphile and determine the biological properties and functionalities of CYP in this bacterium. Our study employed the usage of computational methods to search for the novel CYP from CYP structural databases to identify the conserved pattern, functional domain and sequence properties of the uncharacterized CYP from B. lehensis G1. A computational homology model of the protein's structure was generated and a docking analysis was performed to provide useful structural knowledge on the enzyme's possible substrate and their interaction. Sequence analysis indicated that the newly identified CYP, termed CYP107CB2, contained the fingerprint heme binding sequence motif FxxGxxxCxG at position 336-345 as well as other highly conserved motifs characteristic of cytochrome P450 proteins. Using docking studies, we identified Ser-79, Leu-81, Val-231, Val-279, Val-383, Ala-232, Thr-236 and Thr-283 as important active site residues capable of stabilizing interactions with several potential substrates, including vitamin D3, 25-hydroxyvitamin D3 and 1α-hydroxyvitamin D3, in which all substrates docked proximally to the enzyme's heme center. Biochemical analysis indicated that CYP107CB2 is a biologically active protein to produce 1α,25-dihydroxyvitamin D3 from 1α-hydroxyvitamin D3. Based on these results, we conclude that the novel CYP107CB2 identified from B. lehensis G1 is a putative vitamin D hydroxylase which is possibly capable of catalyzing the bioconversion of parental vitamin D3 to calcitriol, or related metabolic products.
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