Browse publications by year: 2014

  1. Plieskatt JL, Rinaldi G, Feng Y, Levine PH, Easley S, Martinez E, et al.
    J Transl Med, 2014;12:3.
    PMID: 24393330 DOI: 10.1186/1479-5876-12-3
    Nasopharyngeal carcinoma (NPC) is a solid tumor of the head and neck. Multimodal therapy is highly effective when NPC is detected early. However, due to the location of the tumor and the absence of clinical signs, early detection is difficult, making a biomarker for the early detection of NPC a priority. The dysregulation of small non-coding RNAs (miRNAs) during carcinogenesis is the focus of much current biomarker research. Herein, we examine several miRNA discovery methods using two sample matrices to identify circulating miRNAs (c-miRNAs) associated with NPC.
    MeSH terms: Aged; Aged, 80 and over; Herpesvirus 4, Human/genetics; Female; Humans; Malaysia; Male; Middle Aged; Nasopharyngeal Neoplasms/blood; Nasopharyngeal Neoplasms/genetics*; RNA, Neoplasm/genetics; RNA, Neoplasm/metabolism; RNA, Viral/genetics; RNA, Viral/metabolism; Biomarkers, Tumor/blood; Biomarkers, Tumor/genetics; Gene Expression Regulation, Neoplastic; Cluster Analysis; Case-Control Studies; Paraffin Embedding; Tissue Fixation; DNA, Complementary/genetics; DNA, Complementary/metabolism; Oligonucleotide Array Sequence Analysis; Gene Expression Profiling/methods*; MicroRNAs/blood; MicroRNAs/genetics*; MicroRNAs/metabolism; Real-Time Polymerase Chain Reaction
  2. Zohdi N, Mahdavi F, Abdullah LC, Choong TS
    J Environ Health Sci Eng, 2014 Jan 06;12(1):3.
    PMID: 24393401 DOI: 10.1186/2052-336X-12-3
    Boron removal capacity of multi-walled carbon nanotubes (MWCNTs) modified with tartaric acid was investigated in this study. Modification of MWCNTs with tartaric acid was confirmed by Boehm surface chemistry method and fourier transform infra-red (FT-IR) spectroscopy. Experiments were performed to determine the adsorption isotherm and adsorption thermodynamic parameters of boron adsorption on tartaric acid modified MWCNTs (TA-MWCNTs). The effect of variables including initial pH, dosage of adsorbent, contact time and temperature was investigated. Analysis of data showed that adsorption equilibrium could be better described by Freundlich isotherm and the maximum adsorption capacities obtained at the pH of 6.0 was 1.97 mg/g. The estimated thermodynamic values of free energy (ΔG°), entropy (ΔS°) and enthalpy (ΔH°) indicated a spontaneous and an endothermic process. Furthermore, the TA-MWCNTs was magnetized for separation of boron-contaminated adsorbent from aqueous solution by applying magnetic field. The results showed that magnetic TA-MWCNTs particles were separated effectively after adsorption from contaminated water.
  3. Shwter AN, Abdullah NA, Alshawsh MA, Alsalahi A, Hajrezaei M, Almaqrami AA, et al.
    J Ethnopharmacol, 2014 Feb 12;151(3):1194-1201.
    PMID: 24393787 DOI: 10.1016/j.jep.2013.12.044
    ETHNOPHARMACOLOGICAL RELEVANCE: Gynura procumbens is commonly used as a traditional medicinal plant in Malaysia for treatment of many diseases. To investigate the chemopreventive properties of Gynura procumbens on azoxymethane (AOM)-induced aberrant crypt foci (ACF) in rats.

    METHODS: Five groups of adult male rats were used in this experiment. Normal/control group; the rats were injected subcutaneously with 15 mg/kg of sterile normal saline once a week for two weeks, and orally administered with 10% Tween 20 (5 mL/kg). Carcinogen and treatment groups; the rats were injected subcutaneously each with 15 mg/kg body weight AOM once a week for 2 weeks and were continued to be fed for two months, respectively with 10% Tween 20, 500 and 250mg/kg body weight plant extracts. Reference group; the rats were injected subcutaneously with 15 mg/kg body weight AOM once a week for 2 weeks, and injected intraperitoneally with fluorouracil 35 mg/kg body weight for five consecutive days.

    RESULT: Total ACF detected in methylene blue stained whole mounts of rat colon were 21, 23and 130 in rats fed with 500, 250 mg/kg body weight treatment and carcinogen groups, respectively. Treatment with high and low doses of the plant extract led to83.6% and 82.2% decrease in the total crypts in the groups fed 500 mg/kg and 250 mg/kg Gynura procumbens respectively compared to carcinogen group. Immunohistochemical staining of ACF showed suppressed azoxymethane induced colonic cell proliferation and Bcl-2 expression. Glutathione-S-transfarase and superoxide dismutase activities were higher in treated rats compared to carcinogen groups.

    CONCLUSION: Gynura procumbens reduced the incidence of AOM induced ACF. The findings showed that Gynura procumbens may have antiproliferative and antioxidative properties. Moreover, Gynura procumbens possesses the medicinal properties to prevent colon cancer.

    MeSH terms: Animals; Antioxidants/therapeutic use*; Antioxidants/toxicity; Antioxidants/chemistry; Azoxymethane; Carcinogens; Colon/drug effects; Colon/metabolism; Colon/pathology; Female; Glutathione Transferase/metabolism; Male; Malondialdehyde/metabolism; Phytotherapy; Phenols/analysis; Plant Extracts/therapeutic use*; Plant Extracts/toxicity; Plant Extracts/chemistry; Superoxide Dismutase/metabolism; Colorectal Neoplasms/chemically induced; Colorectal Neoplasms/prevention & control; Rats, Sprague-Dawley; Plant Leaves; Chemoprevention; Asteraceae*; Toxicity Tests, Acute; Rats; Aberrant Crypt Foci/chemically induced; Aberrant Crypt Foci/prevention & control*
  4. Chong ET, Lee CC, Chua KH, Chuah JA, Lee PC
    BMJ Open, 2014;4(1):e004109.
    PMID: 24394801 DOI: 10.1136/bmjopen-2013-004109
    Our study aimed to investigate the association of CYP2E1 C-1019T RsaI and T7678A DraI polymorphisms and factors such as age, gender and ethnicity to the risk of gastrointestinal cancer (GIC) in Malaysians.
    MeSH terms: Adult; Female; Gastrointestinal Neoplasms/genetics*; Gastrointestinal Neoplasms/epidemiology*; Humans; Malaysia; Male; Middle Aged; Risk Factors; Case-Control Studies; Cytochrome P-450 CYP2E1/genetics*; Polymorphism, Single Nucleotide*; Asian Continental Ancestry Group
  5. Tay LX, Lim CK, Mansor A, Kamarul T
    Int J Med Sci, 2014;11(1):24-33.
    PMID: 24396283 DOI: 10.7150/ijms.7244
    This preliminary study aims to determine the differentially expressed proteins from chondrogenic differentiated multipotent stromal cells (cMSCs) in comparison to undifferentiated multipotent stromal cells (MSCs) and adult chondrocytes (ACs).
    MeSH terms: Animals; Cell Differentiation*; Cells, Cultured; Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism; Glycosaminoglycans/metabolism; Male; Phenazines/metabolism; Proteins/metabolism*; Rabbits; Electrophoresis, Gel, Two-Dimensional; Chondrocytes/cytology; Chondrocytes/metabolism*; Collagen Type II/metabolism; Principal Component Analysis; Multipotent Stem Cells/cytology; Multipotent Stem Cells/metabolism*; Cofilin 1/metabolism; Mesenchymal Stromal Cells/cytology; Mesenchymal Stromal Cells/metabolism*
  6. Naveen SV, Ahmad RE, Hui WJ, Suhaeb AM, Murali MR, Shanmugam R, et al.
    Int J Med Sci, 2014;11(1):97-105.
    PMID: 24396291 DOI: 10.7150/ijms.6964
    Monosodium -iodoacetate (MIA)-induced animal model of osteoarthritis (OA) is under-utilised despite having many inherent advantages. At present, there is lack of studies that directly compare the degenerative changes induced by MIA with the surgical osteoarthritis induction method and human osteoarthritis, which would further verify a greater use of this model. Therefore, we compared the histological, biochemical and biomechanical characteristics in rat model using MIA against the anterior cruciate ligament transection (ACLT) and human cartilage with clinically established osteoarthritis. The right knees of Sprague-Dawley rats were subjected to either MIA or ACLT (n=18 in each group). Six rats were used as controls. Human cartilage samples were collected and compared from patients clinically diagnosed with (n=7) and without osteoarthritis (n=3). Histological, biochemical (Glycosaminoglycans/total protein) and biomechanical (cartilage stiffness) evaluations were performed at the end of the 1(st) and 2(nd) week after OA induction. For human samples, evaluations were performed at the time of sampling. Histopathological changes in the MIA group were comparable to that observed in the ACLT group and human OA. The Mankin scores of the 3 groups were comparable (MIA: 11.5 ± 1.0; ACLT: 10.1 ± 1.1; human OA: 13.2 ± 0.8). Comparable reduction in Glycosaminoglycan/total protein content in the intervention groups were observed (MIA: 7 ± 0.6; ACLT: 6.6 ± 0.5; human OA: 3.1 ± 0.7). Cartilage stiffness score were 24.2 ± 15.3 Mpa for MIA, 25.3 ± 4.8 for ACLT and 0.5 ± 0.0 Mpa for human OA. The MIA model produces comparable degenerative changes to ACLT and human OA with the advantage of being rapid, minimally invasive and reproducible. Therefore, wider utilisation of MIA as animal translational OA model should perhaps be advocated.
    MeSH terms: Animals; Cartilage, Articular/physiopathology*; Disease Models, Animal; Glycosaminoglycans/metabolism*; Humans; Knee Joint/physiopathology; Osteoarthritis/chemically induced; Osteoarthritis/metabolism; Osteoarthritis/physiopathology*; Anterior Cruciate Ligament/surgery; Rats, Sprague-Dawley; Iodoacetic Acid/toxicity; Rats
  7. Abdul Latif NS, Wake GC, Reglinski T, Elmer PA
    J Theor Biol, 2014 Apr 21;347:144-50.
    PMID: 24398025 DOI: 10.1016/j.jtbi.2013.12.023
    Plant disease control has traditionally relied heavily on the use of agrochemicals despite their potentially negative impact on the environment. An alternative strategy is that of induced resistance (IR). However, while IR has proven effective in controlled environments, it has shown variable field efficacy, thus raising questions about its potential for disease management in a given crop. Mathematical modelling of IR assists researchers with understanding the dynamics of the phenomenon in a given plant cohort against a selected disease-causing pathogen. Here, a prototype mathematical model of IR promoted by a chemical elicitor is proposed and analysed. Standard epidemiological models describe that, under appropriate environmental conditions, Susceptible plants (S) may become Diseased (D) upon exposure to a compatible pathogen or are able to Resist the infection (R) via basal host defence mechanisms. The application of an elicitor enhances the basal defence response thereby affecting the relative proportion of plants in each of the S, R and D compartments. IR is a transient response and is modelled using reversible processes to describe the temporal evolution of the compartments. Over time, plants can move between these compartments. For example, a plant in the R-compartment can move into the S-compartment and can then become diseased. Once in the D-compartment, however, it is assumed that there is no recovery. The terms in the equations are identified using established principles governing disease transmission and this introduces parameters which are determined by matching data to the model using computer-based algorithms. These then give the best match of the model with experimental data. The model predicts the relative proportion of plants in each compartment and quantitatively estimates elicitor effectiveness. An illustrative case study will be given; however, the model is generic and will be applicable for a range of plant-pathogen-elicitor scenarios.
    MeSH terms: Models, Biological*; Plant Diseases*
  8. Khan KM, Jamil W, Ambreen N, Taha M, Perveen S, Morales GA
    Ultrason Sonochem, 2014 May;21(3):1200-5.
    PMID: 24398059 DOI: 10.1016/j.ultsonch.2013.12.011
    Aldazines (Bis-Schiff bases) 1-24 were synthesized using aromatic aldehydes (heterocyclic and benzaldehydes) and hydrazine hydrate under reflux using conventional heating and/or via ultrasound irradiation using BiCl3 as catalyst. Ultrasonication conditions with cat. BiCl3 proved to be an effective, environmentally friendly synthetic procedure. This methodology is robust in the presence of electron donating and electron withdrawing groups affording desired products with high yields (>95%) in just a couple of minutes vs. hours using conventional heating.
    MeSH terms: Electron Transport; Kinetics; Schiff Bases/chemical synthesis*; Ultrasonics*; Chemistry Techniques, Synthetic/methods*
  9. Mishra RK, Ramasamy K, Ahmad NA, Eshak Z, Majeed AB
    J Mater Sci Mater Med, 2014 Apr;25(4):999-1012.
    PMID: 24398912 DOI: 10.1007/s10856-013-5132-x
    Stimuli responsive hydrogels have shown enormous potential as a carrier for targeted drug delivery. In this study we have developed novel pH responsive hydrogels for the delivery of 5-fluorouracil (5-FU) in order to alleviate its antitumor activity while reducing its toxicity. We used 2-(methacryloyloxyethyl) trimetylammonium chloride a positively charged monomer and methacrylic acid for fabricating the pH responsive hydrogels. The released 5-FU from all except hydrogel (GEL-5) remained biologically active against human colon cancer cell lines [HT29 (IC50 = 110-190 μg ml(-1)) and HCT116 (IC50 = 210-390 μg ml(-1))] but not human skin fibroblast cells [BJ (CRL2522); IC50 ≥ 1000 μg ml(-1)]. This implies that the copolymer hydrogels (1-4) were able to release 5-FU effectively to colon cancer cells but not normal human skin fibroblast cells. This is probably due to the shorter doubling time that results in reduced pH in colon cancer cells when compared to fibroblast cells. These pH sensitive hydrogels showed well defined cell apoptosis in HCT116 cells through series of events such as chromatin condensation, membrane blebbing, and formation of apoptotic bodies. No cell killing was observed in the case of blank hydrogels. The results showed the potential of these stimuli responsive polymer hydrogels as a carrier for colon cancer delivery.
    MeSH terms: Antineoplastic Agents/administration & dosage*; Antineoplastic Agents/pharmacokinetics; Biocompatible Materials/chemical synthesis; Biocompatible Materials/chemistry; Cell Line; Colonic Neoplasms/drug therapy*; Colonic Neoplasms/metabolism; Colonic Neoplasms/pathology; Drug Carriers/chemistry; Fluorouracil/administration & dosage*; Fluorouracil/pharmacokinetics; Humans; Hydrogen-Ion Concentration; Materials Testing; Methacrylates/chemistry*; Microscopy, Electron, Scanning; Polymethacrylic Acids/chemical synthesis; Polymethacrylic Acids/chemistry*; Thermodynamics; Viscosity; X-Ray Diffraction; Drug Delivery Systems*; Apoptosis/drug effects; Spectroscopy, Fourier Transform Infrared; HT29 Cells; Hydrogels; HCT116 Cells
  10. Sakthiswary R, Suresh E
    Lupus, 2014 Mar;23(3):225-35.
    PMID: 24399812 DOI: 10.1177/0961203313519159
    OBJECTIVE: The objective of this review is to evaluate the evidence for efficacy of methotrexate (MTX) in systemic lupus erythematosus (SLE).
    METHODS: A comprehensive, computerized search was performed in MEDLINE (PubMed), EMBASE and the Cochrane Controlled Trials registry to screen for studies that examined the efficacy of MTX in adult SLE patients. The Jadad scoring system was used to assess study quality, and data were pooled using the random effects model.
    RESULTS: Of the 53 articles that were identified, 44 were excluded. Nine studies (including three randomized controlled and six observational) were eligible for inclusion. All of the included studies predominantly involved patients with arthritis or mucocutaneous features. There was significant reduction of the SLE Disease Activity Index (SLEDAI) among MTX-treated patients when compared with controls (p = 0.001, odds ratio (OR) 0.444, 95% confidence interval (CI) 0.279 to 0.707). There was also significant reduction in the average dose of corticosteroids among MTX-treated patients when compared with controls (p = 0.001, OR 0.335, 95% CI 0.202 to 0.558). The effect of MTX on laboratory and serological markers, including erythrocyte sedimentation rate, anti-dsDNA and complement levels (C3 and C4), could not be determined because of the limited numbers of controlled trials.
    CONCLUSION: The use of MTX is associated with significant reductions in SLEDAI and the average dose of corticosteroids in adult patients with SLE.
    KEYWORDS: SLE; Systemic lupus erythematosus; efficacy; lupus; methotrexate
    MeSH terms: Adrenal Cortex Hormones/therapeutic use; Drug Therapy, Combination; Humans; Immunosuppressive Agents/therapeutic use*; Lupus Erythematosus, Systemic/blood; Lupus Erythematosus, Systemic/diagnosis; Lupus Erythematosus, Systemic/drug therapy*; Methotrexate/therapeutic use*; Remission Induction; Biomarkers/blood; Odds Ratio; Treatment Outcome
  11. Shaharir SS, Ghafor AH, Said MS, Kong NC
    Lupus, 2014 Apr;23(4):436-42.
    PMID: 24399814 DOI: 10.1177/0961203313518624
    INTRODUCTION: Renal involvement is the most common serious complication in patients with systemic lupus erythematosus (SLE).
    OBJECTIVE: The objective of this article is to investigate and determine the associated factors of disease damage among lupus nephritis (LN) patients.
    METHODS: Medical records of LN patients who attended regular follow-up for at least one year in the Nephrology/SLE Clinic, Universiti Kebangsaan Malaysia Medical Centre (UKMMC), were reviewed. Their Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index scores were noted. Univariate analysis and multivariable regression analysis were performed to determine the independent factors of disease damage in LN.
    RESULTS: A total of 150 patients were included and their follow-up duration ranged from one to 20 years. Sixty (40%) LN patients had disease damage (SDI ≥1). In the univariate analysis, it was associated with age, longer disease duration, antiphospholipid syndrome (APS), higher maximum daily oral prednisolone dose (mg/day), lower mean C3 and C4, higher chronicity index and global sclerosis on renal biopsies (p < 0.05). Patients who received early (≤3 months after the SLE diagnosis) hydroxychloroquine (HCQ), optimum HCQ dose at 6.5 mg/kg/day and achieved early complete remission (CR) were less likely to have disease damage (p < 0.05). After adjustment for age, gender, disease duration and severity, multivariable regression analysis revealed that a higher maximum daily dose of oral prednisolone was independently associated with disease damage while early HCQ and CR were associated with lower disease damage.
    CONCLUSION: Higher maximum daily prednisolone dose predicted disease damage whereas treatment with early HCQ and early CR had a protective role against disease damage.
    KEYWORDS: Antiphospholipid syndrome; lupus nephritis; systemic lupus erythematosus

    Study site: Nephrology/SLE Clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM)
    MeSH terms: Adult; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Hospitals, University; Humans; Hydroxychloroquine/administration & dosage; Hydroxychloroquine/therapeutic use*; Lupus Nephritis/epidemiology; Lupus Nephritis/physiopathology*; Malaysia/epidemiology; Male; Middle Aged; Outpatient Clinics, Hospital; Prednisolone/administration & dosage; Prednisolone/therapeutic use*; Regression Analysis; Remission Induction; Retrospective Studies; Risk Factors; Severity of Illness Index; Time Factors; Multivariate Analysis; Antiphospholipid Syndrome/epidemiology*
  12. Chan TC, Hwang JS, Chen RH, King CC, Chiang PH
    BMC Public Health, 2014 Jan 08;14:11.
    PMID: 24400725 DOI: 10.1186/1471-2458-14-11
    BACKGROUND: Severe epidemics of enterovirus have occurred frequently in Malaysia, Singapore, Taiwan, Cambodia, and China, involving cases of pulmonary edema, hemorrhage and encephalitis, and an effective vaccine has not been available. The specific aim of this study was to understand the epidemiological characteristics of mild and severe enterovirus cases through integrated surveillance data.

    METHODS: All enterovirus cases in Taiwan over almost ten years from three main databases, including national notifiable diseases surveillance, sentinel physician surveillance and laboratory surveillance programs from July 1, 1999 to December 31, 2008 were analyzed. The Pearson's correlation coefficient was applied for measuring the consistency of the trends in the cases between different surveillance systems. Cross correlation analysis in a time series model was applied for examining the capability to predict severe enterovirus infections. Poisson temporal, spatial and space-time scan statistics were used for identifying the most likely clusters of severe enterovirus outbreaks. The directional distribution method with two standard deviations of ellipse was applied to measure the size and the movement of the epidemic.

    RESULTS: The secular trend showed that the number of severe EV cases peaked in 2008, and the number of mild EV cases was significantly correlated with that of severe ones occurring in the same week [r = 0.553, p 

    MeSH terms: Enterovirus Infections/epidemiology*; Enterovirus Infections/prevention & control; Enterovirus Infections/virology; Enterovirus; Humans; Population Surveillance*; Severity of Illness Index; Taiwan/epidemiology; Enterovirus A, Human/isolation & purification*; Epidemics/prevention & control; Spatio-Temporal Analysis
  13. Norasyikin AW, Rozita M, Mohd Johan MJ, Suehazlyn Z
    Med Princ Pract, 2014;23(4):387-9.
    PMID: 24401542 DOI: 10.1159/000357645
    OBJECTIVE: To report an uncommon presentation of a rare case of autoimmune polyglandular syndrome type IIIb in an elderly woman.
    CLINICAL PRESENTATION AND INTERVENTION: A 62-year-old woman presented with anaemic symptoms and jaundice. Blood tests showed macrocytic anaemia due to vitamin B12 deficiency with Coombs negative haemolysis. A thyroid function test was consistent with hypothyroidism. Autoimmune antibody assays were positive for anti-parietal cell, anti-intrinsic factor and anti-thyroid peroxidase antibodies. A final diagnosis of autoimmune thyroiditis with pernicious anaemia, which constituted autoimmune polyglandular syndrome type IIIb, was made and the patient was treated with L-thyroxine, vitamin B12 injection and a blood transfusion. She was discharged uneventfully after a week of hospitalization.
    CONCLUSION: This case showed that the presence of one autoimmune endocrine disease should prompt clinicians to look for other coexisting autoimmune diseases which may be asymptomatic despite positive autoantibodies.
    MeSH terms: Anemia, Macrocytic/physiopathology; Diagnosis, Differential; Female; Humans; Hypothyroidism/physiopathology; Jaundice/physiopathology; Malaysia; Middle Aged; Thrombocytopenia/physiopathology; Thyroid Function Tests; Thyroiditis, Autoimmune; Vitamin B 12 Deficiency/physiopathology; Polyendocrinopathies, Autoimmune/diagnosis*; Polyendocrinopathies, Autoimmune/physiopathology*
  14. Ambati RR, Phang SM, Ravi S, Aswathanarayana RG
    Mar Drugs, 2014 Jan 07;12(1):128-52.
    PMID: 24402174 DOI: 10.3390/md12010128
    There is currently much interest in biological active compounds derived from natural resources, especially compounds that can efficiently act on molecular targets, which are involved in various diseases. Astaxanthin (3,3'-dihydroxy-β, β'-carotene-4,4'-dione) is a xanthophyll carotenoid, contained in Haematococcus pluvialis, Chlorella zofingiensis, Chlorococcum, and Phaffia rhodozyma. It accumulates up to 3.8% on the dry weight basis in H. pluvialis. Our recent published data on astaxanthin extraction, analysis, stability studies, and its biological activities results were added to this review paper. Based on our results and current literature, astaxanthin showed potential biological activity in in vitro and in vivo models. These studies emphasize the influence of astaxanthin and its beneficial effects on the metabolism in animals and humans. Bioavailability of astaxanthin in animals was enhanced after feeding Haematococcus biomass as a source of astaxanthin. Astaxanthin, used as a nutritional supplement, antioxidant and anticancer agent, prevents diabetes, cardiovascular diseases, and neurodegenerative disorders, and also stimulates immunization. Astaxanthin products are used for commercial applications in the dosage forms as tablets, capsules, syrups, oils, soft gels, creams, biomass and granulated powders. Astaxanthin patent applications are available in food, feed and nutraceutical applications. The current review provides up-to-date information on astaxanthin sources, extraction, analysis, stability, biological activities, health benefits and special attention paid to its commercial applications.
    MeSH terms: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Antioxidants; Biological Availability; Biological Products/chemistry; Biotechnology; Cardiovascular Agents; Drug Stability; Humans; Hypoglycemic Agents; Immunologic Factors; Marine Biology; Xanthophylls/adverse effects; Xanthophylls/biosynthesis; Xanthophylls/isolation & purification; Xanthophylls/pharmacokinetics; Xanthophylls/pharmacology; Xanthophylls/chemistry
  15. Islahudin F, Tindall SM, Mellor IR, Swift K, Christensen HE, Fone KC, et al.
    Sci Rep, 2014 Jan 09;4:3618.
    PMID: 24402577 DOI: 10.1038/srep03618
    The major antimalarial drug quinine perturbs uptake of the essential amino acid tryptophan, and patients with low plasma tryptophan are predisposed to adverse quinine reactions; symptoms of which are similar to indications of tryptophan depletion. As tryptophan is a precursor of the neurotransmitter serotonin (5-HT), here we test the hypothesis that quinine disrupts serotonin function. Quinine inhibited serotonin-induced proliferation of yeast as well as human (SHSY5Y) cells. One possible cause of this effect is through inhibition of 5-HT receptor activation by quinine, as we observed here. Furthermore, cells exhibited marked decreases in serotonin production during incubation with quinine. By assaying activity and kinetics of the rate-limiting enzyme for serotonin biosynthesis, tryptophan hydroxylase (TPH2), we showed that quinine competitively inhibits TPH2 in the presence of the substrate tryptophan. The study shows that quinine disrupts both serotonin biosynthesis and function, giving important new insight to the action of quinine on mammalian cells.
    MeSH terms: Antimalarials/pharmacology*; Humans; Neuroblastoma/pathology; Quinine/pharmacology*; Saccharomyces cerevisiae/drug effects; Saccharomyces cerevisiae/growth & development; Serotonin/biosynthesis*; Serotonin/physiology; Tryptophan Hydroxylase/antagonists & inhibitors; Cell Line, Tumor
  16. Baharuddin MY, Salleh ShH, Suhasril AA, Zulkifly AH, Lee MH, Omar MA, et al.
    Artif Organs, 2014 Jul;38(7):603-8.
    PMID: 24404766 DOI: 10.1111/aor.12222
    Total hip arthroplasty is a flourishing orthopedic surgery, generating billions of dollars of revenue. The cost associated with the fabrication of implants has been increasing year by year, and this phenomenon has burdened the patient with extra charges. Consequently, this study will focus on designing an accurate implant via implementing the reverse engineering of three-dimensional morphological study based on a particular population. By using finite element analysis, this study will assist to predict the outcome and could become a useful tool for preclinical testing of newly designed implants. A prototype is then fabricated using 316L stainless steel by applying investment casting techniques that reduce manufacturing cost without jeopardizing implant quality. The finite element analysis showed that the maximum von Mises stress was 66.88 MPa proximally with a safety factor of 2.39 against endosteal fracture, and micromotion was 4.73 μm, which promotes osseointegration. This method offers a fabrication process of cementless femoral stems with lower cost, subsequently helping patients, particularly those from nondeveloped countries.
    MeSH terms: Hip Prosthesis/economics*; Humans; Prosthesis Design; Stainless Steel/economics*; Stainless Steel/chemistry; Stress, Mechanical; Arthroplasty, Replacement, Hip/economics; Finite Element Analysis
  17. Jamshed SQ, Shamsudin SH
    Int J Pharm Pract, 2014 Feb;22(1):101-2.
    PMID: 24404933 DOI: 10.1111/ijpp.12036
    MeSH terms: Education, Pharmacy/methods*; Writing*
  18. Doughty MJ
    Clin Exp Optom, 2014 May;97(3):256-63.
    PMID: 24405014 DOI: 10.1111/cxo.12127
    PURPOSE: The aim was to assess the morphology of the Asian corneal endothelium, particularly the index of polymegethism and its relationship to endothelial cell density assessments.
    METHODS: The central regions of the corneal endothelium of 72 healthy, normal weight, non-contact lens wearers were assessed by non-contact specular microscopy. There were six groups of persons, aged between 18 and 27 years, whose ethnic origins were self-reported as Asian (Mainland China, Hong Kong, India, Malaysia, Pakistan or other Asian groups). Single images including at least 100 contiguous cells were obtained from each subject and were processed by planimetry after manual border marking to minimise errors. Calculations were made of the coefficient of variation of cell area (COV; polymegethism) as well as the endothelial cell density and percentage of six-sided cells.
    RESULTS: The COV values ranged from 18 to 30.4 per cent (group mean 24.5 ± 2.8 per cent). The corneas had essentially normal thickness (0.530 ± 0.026 mm), with the endothelia showing a high percentage of six-sided cells (66.3 ± 7.1 per cent) and none showing even mild signs of polymegethism. Endothelial cell density estimates based on average cell areas ranged from 2,020 to 3,623 cells per mm(2) and from 2,157 to 3,835 with calculations based on individual cell areas. The difference between the two estimates of endothelial cell density was strongly related to the coefficient of variation (r = 0.765).
    CONCLUSIONS: This result is consistent with several older reports indicating that it is uncommon to find polymegethism in healthy young adult Asian individuals. Nonetheless, even low coefficient of variation values can substantially affect the estimations of the cell density.
    KEYWORDS: Asian; cornea; endothelium; human; polymegathism
    MeSH terms: Adolescent; Adult; Cell Count; Endothelium, Corneal/cytology*; Female; Follow-Up Studies; Great Britain; Humans; Malaysia; Male; Prospective Studies; Reference Values; Asian Continental Ancestry Group*; Young Adult
  19. Samat N, Tan PJ, Shaari K, Abas F, Lee HB
    Anal Chem, 2014 Feb 4;86(3):1324-31.
    PMID: 24405504 DOI: 10.1021/ac403709a
    Photodynamic therapy (PDT) is an alternative treatment for cancer that involves administration of a photosensitive drug or photosensitizer that localizes at the tumor tissue followed by in situ excitation at an appropriate wavelength of light. Tumour tissues are then killed by cytotoxic reactive oxygen species generated by the photosensitizer. Targeted excitation and photokilling of affected tissues is achieved through focal light irradiation, thereby minimizing systemic side effects to the normal healthy tissues. Currently, there are only a small number of photosensitizers that are in the clinic and many of these share the same structural core based on cyclic tetrapyrroles. This paper describes how metabolic tools are utilized to prioritize natural extracts to search for structurally new photosensitizers from Malaysian biodiversity. As proof of concept, we analyzed 278 photocytotoxic extracts using a hyphenated technique of liquid chromatography-mass spectrometry coupled with principal component analysis (LC-MS-PCA) and prioritized 27 extracts that potentially contained new photosensitizers for chemical dereplication using an in-house UPLC-PDA-MS-Photocytotoxic assay platform. This led to the identification of 2 new photosensitizers with cyclic tetrapyrrolic structures, thereby demonstrating the feasibility of the metabolic approach.
    MeSH terms: Biological Products/analysis*; Biological Products/isolation & purification; Biological Products/therapeutic use; Chromatography, Liquid; Photochemotherapy*; Plant Extracts/analysis*; Plant Extracts/isolation & purification; Plant Extracts/therapeutic use; Mass Spectrometry*; Photosensitizing Agents/analysis*; Photosensitizing Agents/isolation & purification; Photosensitizing Agents/therapeutic use; Principal Component Analysis*; Metabolomics/methods*
  20. Al-Darraji HA, Kamarulzaman A, Altice FL
    BMC Public Health, 2014 Jan 10;14:22.
    PMID: 24405607 DOI: 10.1186/1471-2458-14-22
    Prisons continue to fuel tuberculosis (TB) epidemics particularly in settings where access to TB screening and prevention services is limited. Malaysia is a middle-income country with a relatively high incarceration rate of 138 per 100,000 population. Despite national TB incidence rate remaining unchanged over the past ten years, data about TB in prisons and its contribution to the overall national rates does not exist. This survey was conducted to address the prevalence of latent TB infection (LTBI) in Malaysia's largest prison.
    MeSH terms: Adult; Female; Humans; Malaysia/epidemiology; Male; Middle Aged; Prisons; Surveys and Questionnaires; Risk Factors; Tuberculin Test; HIV Infections/epidemiology; Prevalence; Logistic Models; Needle Sharing; CD4 Lymphocyte Count; Substance-Related Disorders/complications; Latent Tuberculosis/epidemiology*; Latent Tuberculosis/prevention & control
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