Displaying publications 81 - 100 of 200 in total

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  1. Fulltext Perceptions and attitudes towards medication error reporting in primary care clinics: a qualitative study in Malaysia
    Samsiah A, Othman N, Jamshed S, Hassali MA
    PLoS One, 2016;11(12):e0166114.
    PMID: 27906960 DOI: 10.1371/journal.pone.0166114
    OBJECTIVE: To explore and understand participants' perceptions and attitudes towards the reporting of medication errors (MEs).

    METHODS: A qualitative study using in-depth interviews of 31 healthcare practitioners from nine publicly funded, primary care clinics in three states in peninsular Malaysia was conducted for this study. The participants included family medicine specialists, doctors, pharmacists, pharmacist assistants, nurses and assistant medical officers. The interviews were audiotaped and transcribed verbatim. Analysis of the data was guided by the framework approach.

    RESULTS: Six themes and 28 codes were identified. Despite the availability of a reporting system, most of the participants agreed that MEs were underreported. The nature of the error plays an important role in determining the reporting. The reporting system, organisational factors, provider factors, reporter's burden and benefit of reporting also were identified.

    CONCLUSIONS: Healthcare practitioners in primary care clinics understood the importance of reporting MEs to improve patient safety. Their perceptions and attitudes towards reporting of MEs were influenced by many factors which affect the decision-making process of whether or not to report. Although the process is complex, it primarily is determined by the severity of the outcome of the errors. The participants voluntarily report the errors if they are familiar with the reporting system, what error to report, when to report and what form to use.
  2. Whole-Exome Sequencing of ETV6/RUNX1 in Four Childhood Acute Lymphoblastic Leukaemia Cases
    Zakaria Z, Othman N, Ismail A, Kamaluddin NR, Esa E, Abdul Rahman EJ, et al.
    Asian Pac J Cancer Prev, 2017 04 01;18(4):1169-1175.
    PMID: 28548470
    Background: ETV6/RUNX1 gene fusion is the most frequently seen chromosomal abnormality in childhood acute
    lymphobastic leukamia (ALL). However, additional genetic changes are known to be required for the development of
    this type of leukaemia. Therefore, we here aimed to assess the somatic mutational profile of four ALL cases carrying the
    ETV6/RUNX1 fusion gene using whole-exome sequencing. Methods: DNA was isolated from bone marrow samples
    using a QIAmp DNA Blood Mini kit and subsequently sequenced using the Illumina MiSeq system. Results: We
    identified 12,960 to17,601 mutations in each sample, with a total of 16,466 somatic mutations in total. Some 15,533
    variants were single nucleotide polymorphisms (SNPs), 129 were substitutions, 415 were insertions and 389 were
    deletions. When taking into account the coding region and protein impact, 1,875 variants were synonymous and 1,956
    were non-synonymous SNPs. Among non-synonymous SNPs, 1,862 were missense, 13 nonsense, 35 frameshifts, 11
    nonstop, 3 misstart, 15 splices disrupt and 17 in-frame indels. A total of 86 variants were located in leukaemia-related
    genes of which 32 variants were located in the coding regions of GLI2, SP140, GATA2, SMAD5, KMT2C, CDH17,
    CDX2, FLT3, PML and MOV10L1. Conclusions: Detection and identification of secondary genetic alterations are
    important in identifying new therapeutic targets and developing rationally designed treatment regimens with less
    toxicity in ALL patients.
  3. Socioeconomic Predictors of Adherence Behavior Among HIV-Positive Patients Receiving Antiretroviral Therapy in Selangor, Malaysia
    Abdulrahman SA, Rampal L, Othman N, Ibrahim F, Kadir Shahar H, Radhakrishnan AP
    Asia Pac J Public Health, 2017 May;29(4):304-314.
    PMID: 28397533 DOI: 10.1177/1010539517700471
    Medication adherence remains a critical link between the prescribed ART regimen and treatment outcome. Several factors may influence adherence behavior. This cross-sectional study aimed to highlight socioeconomic predictors of adherence behavior among a cohort of 242 adult Malaysian patients receiving antiretroviral therapy in Hospital Sungai Buloh, Malaysia, where they were enrolled in a parent study (single-blinded randomized controlled trial) between January and December 2014. Statistical analysis of secondary data on adherence behavior and sociodemographic characteristics of the patients revealed mean age of 33.4 years and ranged from 18 to 64 years; 88.8% were males. A total of 224 (93%) patients who completed 6 months' adherence assessment were included in the model. Of these, 135 (60.3%) achieved optimal adherence. Multivariate binary logistic regression analysis revealed that patient's income and ethnicity were significant predictors of adherence behavior. This may be valuable for targeted programmatic interventions to further enhance successful treatment outcomes among the target population.
  4. Development and initial evaluation of a lateral flow dipstick test for antigen detection of Entamoeba histolytica in stool sample
    Saidin S, Yunus MH, Othman N, Lim YA, Mohamed Z, Zakaria NZ, et al.
    Pathog Glob Health, 2017 May;111(3):128-136.
    PMID: 28335696 DOI: 10.1080/20477724.2017.1300421
    Entamoeba histolytica infection remains a public health concern in developing countries. Early diagnosis of amoebiasis can avoid disease complications, thus this study was aimed at developing a test that can rapidly detect the parasite antigens in stool samples. Rabbits were individually immunized with recombinant pyruvate phosphate dikinase (rPPDK) and E. histolytica excretory-secretory antigens to produce polyclonal antibodies. A rapid dipstick test was produced using anti-rPPDK PAb lined on the dipstick as capture reagent and anti-EhESA PAb conjugated to colloidal gold as the detector reagent. Using E. histolytica-spiked in stool sample of a healthy individual, the detection limit of the dipstick test was found to be 1000 cells ml-1. Meanwhile when rPPDK was spiked in the stool sample, the minimum concentration detected by the dipstick test was 0.1 μg ml-1. The performances of the dipstick, commercial Techlab E. histolytica II enzyme-linked immunosorbent assays (ELISA) and real-time PCR were compared using 70 stool samples from patients infected with Entamoeba species (n = 45) and other intestinal pathogens (n = 25). When compared to real-time PCR, the diagnostic sensitivity of the dipstick for detection of E. histolytica was 65.4% (n = 17/26); while the diagnostic specificity when tested with stool samples containing other intestinal pathogens was 92% (23/25). In contrast, Techlab E. histolytica II ELISA detected 19.2% (5/26) of the E. histolytica-positive samples as compared to real-time PCR. The lateral flow dipstick test produced in this study enabled rapid detection of E. histolytica, thus it showed good potential to be further developed into a diagnostic tool for intestinal amoebiasis.
  5. Recombinant protein expression of Moringa oleifera lectin in methylotrophic yeast as active coagulant for sustainable high turbid water treatment
    Abd Wahid MA, Megat Mohd Noor MJ, Goto M, Sugiura N, Othman N, Zakaria Z, et al.
    Biosci Biotechnol Biochem, 2017 Aug;81(8):1642-1649.
    PMID: 28585494 DOI: 10.1080/09168451.2017.1329617
    The natural coagulant Moringa oleifera lectin (MoL) as cationic protein is a promising candidate in coagulation process of water treatment plant. Introducing the gene encoding MoL into a host, Pichia pastoris, to secrete soluble recombinant protein is assessed in this study. Initial screening using PCR confirmed the insertion of MoL gene, and SDS-PAGE analysis detected the MoL protein at 8 kDa. Cultured optimization showed the highest MoL protein at 520 mg/L was observed at 28 °C for 144 h of culturing by induction in 1% methanol. Approximately, 0.40 mg/mL of recombinant MoL protein showed 95 ± 2% turbidity removal of 1% kaolin suspension. In 0.1% kaolin suspension, the concentration of MoL at 10 μg/mL exhibits the highest turbidity reduction at 68 ± 1%. Thus, recombinant MoL protein from P. pastoris is an effective coagulant for water treatment.
  6. Parallel ELISAs using crude soluble antigen and excretory-secretory antigen for improved serodiagnosis of amoebic liver abscess
    Wong WK, Foo PC, Olivos-Garcia A, Noordin R, Mohamed Z, Othman N, et al.
    Acta Trop, 2017 Aug;172:208-212.
    PMID: 28506795 DOI: 10.1016/j.actatropica.2017.05.017
    Crude soluble antigen (CSA) produced from Entamoeba histolytica trophozoite is conventionally used for serodiagnosis of invasive amoebiasis. However, high background seropositivities by CSA-assay in endemic areas complicate the interpretation of positive result in clinical settings. Instead, incorporating a second assay which indicates active or recent infection into the routine amoebic serology could possibly complement the limitations of CSA-assay. Hence, the present study aimed to evaluate the diagnostic efficacies of indirect ELISAs using CSA and excretory-secretory antigen (ESA) for serodiagnosis of amoebic liver abscess (ALA). Reference standard for diagnosis of ALA at Hospital Universiti Sains Malaysia is based on clinical presentation, radiological imaging and positive indirect haemagglutination assay (titer ≥256). Five groups of human serum samples collected from the hospital included Group I - ALA diagnosed by the reference standard and pus aspirate analysis using real-time PCR (n=10), Group II - ALA diagnosed by the reference standard only (n=41), Group III - healthy control (n=45), Group IV - other diseases control (n=51) and Group V - other infectious diseases control (n=31). For serodiagnosis of ALA serum samples (Group I and II), CSA-ELISA showed sensitivities of 100% for both groups, while ESA-ELISA showed sensitivities of 100% and 88%, respectively. For serodiagnosis of non-ALA serum samples (Group III, IV and V), CSA-ELISA showed specificities of 91%, 75% and 100%, respectively; while ESA-ELISA showed specificities of 96%, 98% and 100%, respectively. Indirect ELISAs using CSA and ESA have shown distinct strength for serodiagnosis of ALA, in terms of sensitivity and specificity, respectively. In conclusion, parallel analysis by both assays improved the overall efficacies of amoebic serology as compared to either single assay.
  7. Multimodality cardiac imaging of submitral left ventricular aneurysm with concurrent descending aorta mycotic aneurysm
    Abdullah H, Jiyen K, Othman N
    BMJ Case Rep, 2017 Sep 27;2017.
    PMID: 28954754 DOI: 10.1136/bcr-2017-221466
    We present a case of a 20-year-old Malay man with underlying tuberculous (TB) lymphadenitis who presented with shortness of breath and found to have submitral left ventricular aneurysm (SLVA). SLVA is well recognised but rare. Incidence of SLVA in Malay has never been documented. This is the first reported case of SLVA in Malays with concomitant thoracic aorta mycotic aneurysm. TB has been reported to be associated with SLVA. Treatment is either surgical or conservative. Imaging is required for diagnosis and preoperative assessment. Multimodality imaging include echocardiography (ECHO), cardiac CTangiography and the robust multiparametric cardiac MR (CMR). ECHO is the first line imaging and useful for initial detection of the aneurysm. CMR including the late gadolinium enhancement allows excellent visualisation of the LV aneurysm, tissue characterisation, cardiac function and detection of associated pathology as shown in this case.
  8. Genome wide allelic imbalance in cervical cancer tissues: an interethnic comparison in Malaysian population
    Ankathil R, Tan S, Ismail M, Dasuki D, Othman N
    Ann Oncol, 2017 Oct;28 Suppl 9:ix94.
    PMID: 32120746 DOI: 10.1093/annonc/mdx697.085
  9. Fulltext In Vitro Testing of Potential Entamoeba histolytica Pyruvate Phosphate Dikinase Inhibitors
    Saidin S, Othman N, Noordin R
    Am J Trop Med Hyg, 2017 Oct;97(4):1204-1213.
    PMID: 28820699 DOI: 10.4269/ajtmh.17-0132
    Adverse effects and resistance to metronidazole have motivated the search for new antiamoebic agents against Entamoeba histolytica. Control of amoeba growth may be achieved by inhibiting the function of the glycolytic enzyme and pyruvate phosphate dikinase (PPDK). In this study, we screened 10 compounds using an in vitro PPDK enzyme assay. These compounds were selected from a virtual screening of compounds in the National Cancer Institute database. The antiamoebic activity of the selected compounds was also evaluated by determining minimal inhibitory concentrations (MICs) and IC50 values using the nitro-blue tetrazolium reduction assay. Seven of the 10 compounds showed inhibitory activities against the adenosine triphosphate (ATP)/inorganic phosphate binding site of the ATP-grasp domain. Two compounds, NSC349156 (pancratistatin) and NSC228137 (7-ethoxy-4-[4-methylphenyl] sulfonyl-3-oxido-2, 1, 3-benzoxadiazol-3-ium), exhibited inhibitory effects on the growth of E. histolytica trophozoites with MIC values of 25 and 50 μM, and IC50 values of 14 and 20.7 μM, respectively.
  10. Synergistic green extraction of nickel ions from electroplating waste via mixtures of chelating and organophosphorus carrier
    Sulaiman RNR, Othman N
    J Hazard Mater, 2017 Oct 15;340:77-84.
    PMID: 28711835 DOI: 10.1016/j.jhazmat.2017.06.060
    The discharge of electroplating waste containing nickel ions has led to environmental issues owing to the toxicity problem mainly to the aquatic organisms and humans. Liquid-liquid extraction offers a great potential treatment for nickel removal with several advantages of simple, high efficiency and high separation factor. In this study, a green synergistic liquid-liquid extraction of nickel ions from electroplating waste solution using chelating oxime (LIX63) and organophosphorus (D2EHPA) carriers individually as well as their synergistic mixture has been studied. The result demonstrated that about 83% of nickel ions have been successfully extracted via the mixture system of 0.08M LIX63 +0.02M D2EHPA with the maximum synergistic enhancement factor, Rmax of 29.56. Meanwhile, the back extraction study also revealed that HNO3 was the most suitable stripping agent while the diluent screening also showed that palm oil has high potential to be incorporated as a diluent in the green synergistic liquid-liquid extraction of nickel.
  11. miR-608 regulates apoptosis in human lung adenocarcinoma via regulation of AKT2
    Othman N, Nagoor NH
    Int J Oncol, 2017 Dec;51(6):1757-1764.
    PMID: 29075783 DOI: 10.3892/ijo.2017.4174
    Lung cancer remains a major health problem with a low 5-year survival rate of patients. Recent studies have shown that dysregulation of microRNAs (miRNAs) are prevalent in lung cancer and these aberrations play a significant role in the progression of tumour progression. In the present study, bioinformatics analyses was employed to predict potential miR-608 targets, which are associated with signaling pathways involved in cancer. Luciferase reporter assay identified AKT2 as a novel target of miR-608, and suppression of its protein levels was validated through western blot analysis. Zebrafish embryos were microinjected with cells transfected with miR-608 to elucidate the role of miR-608 in vivo, and immunostained with antibodies to detect activated caspase-3. We present the first evidence that miR-608 behaves as a tumour suppressor in A549 and SK-LU-1 cells through the regulation of AKT2, suggesting that selective targeting of AKT2 via miR-608 may be developed as a potential therapeutic strategy for miRNA-based non-small cell lung cancer (NSCLC) therapy.
  12. Fulltext Characterization of Musty Odor-Producing Actinomycetes from Tropics and Effects of Temperature on the Production of Musty Odor Compounds
    Anuar NSS, Kassim AA, Utsumi M, Iwamoto K, Goto M, Shimizu K, et al.
    Microbes Environ, 2017 Dec 27;32(4):352-357.
    PMID: 29093279 DOI: 10.1264/jsme2.ME17109
    Geosmin and 2-methylisoborneol (MIB) outbreaks in tropical water bodies, such as Southeast Asia, by actinomycetes have not yet been elucidated in detail. Six Streptomyces isolates from lowland environments in Malaysia were selected and evaluated for their odor production under different temperatures. The gene responsible for the production of geosmin, geoA, was detected in all isolates, while only two isolates harbored tpc, which is responsible for 2-MIB production. This result suggested that geosmin and 2-MIB synthesis pathway genes already existed in the environment in the Tropics of Southeast Asia. Furthermore, our isolates produced musty odor compounds at 30°C, and differences were observed in musty odor production between various temperatures. This result indicated the potential for odor episodes in water bodies of the tropical countries of Southeast Asia throughout the year due to the mean annual ambient temperature of 27°C in the lowlands.
  13. Fulltext Optimisation of Botryococcus sp. growth using synthetic media (N: P) for biodiesel production
    Wellson, R., Othman, N., Matias-Peralta, H.M.
    Pertanika Journal of Science & Technology, 2017;25(105):129-136.
    MyJurnal
    Algae biodiesel is undeniably very promising as an energy substitute for fossil fuel. It mass cultivation though requires huge capital investment. The aim of this study was to find a simple, inexpensive and tolerable media for algae growth. The optimal growth conditions for algae growth were studied. Botryococcus sp. was isolated from Sembrong Dam in Johor, Malaysia. In this study, two media were used, namely bold’s basal medium (BBM) and synthetic media from nitrogen and phosphorus compound. The synthetic media consisted of ammonium chloride and monopotassium phosphate that were blended together and modified into desired ratios. The N: P ratio of 1.5:1 yielded the highest chlorophyll-a concentration and the optimal growth conditions of algae for both media were at 6000 Lux, pH 7 and 30 rpm. The BMM had the highest algae growth, 3.25 x 107cell/ml while the synthetic media yielded a maximum cell concentration of up to 1.025 x 107 cell/ml which is 68.5% lower compared with BBM. The findings of this study point to the importance of large scale production of algae useful for industrial production of biodiesel.
  14. Fulltext The influence of Sulphate Reduction Bacteria on the durability of concrete in seawater condition
    Teddy, T., Irwan, J.M., Othman, N.
    Pertanika Journal of Science & Technology, 2017;25(105):117-122.
    MyJurnal
    Strength and durability are important characteristics of concrete and desired engineering properties. Exposure to aggressive environment threatens durability of concrete. Previous studies on bio-concrete using several types of bacteria, including sulphate reduction bacteria (SRB), had to increase durability of concrete have shown promising results. This study used mixtures designed according to concrete requirement for sea water condition with SRB composition of 3%, 5% and 7% respectively. The curing time were 28, 56 and 90 days respectively. The mechanical properties, namely compressive strength and water permeability, were tested using cube samples. The results showed compressive strength had higher increase than the control at 53.9 Mpa. The SRB with 3%composition had maximum water permeability. Thus, adding SRB in concrete specimens improves compressive strength and water permeability. This is particularly suitable for applications using chloride ion penetration (sea water condition) where corrosion tends to affect durability of concrete constructions.
  15. Fulltext Diagnostic dilemma of reactive arthritis aided by multimodality imaging using MRI, CECT and 18F-FDG PET/CT Scans
    Suppiah S, Zakaria MH, Khalid B, Mohamad Saini S, Othman N
    Malaysian Journal of Medicine and Health Sciences, 2017;13(1):73-77.
    MyJurnal
    Reactive arthritis can be an elusive diagnosis especially in the elderly. A 77-year-old lady, presented with recent history of hip pain. She had been treated for urinary tract infection caused by Chlamydia sp. and had associated weight loss. She was also investigated for possible tuberculosis and occult malignancy. CT scan abdomen/pelvis and MRI revealed peri-articular muscle inflammation. Biopsy of her hip joint failed to find the causative factor. Whole body 18F-FDG PET/CT scan revealed increased FDG uptake at bilateral hip and shoulder joints. She recovered after an intensive course of antibiotics. Thus, she was diagnosed with reactive arthritis. Reactive arthritis is usually a diagnosis of exclusion made by a high index of suspicion and positive serology test. Molecular imaging can be an alternative investigation for joint pains in the elderly, which enables excellent anatomical and functional information to exclude more sinister conditions such as malignancy.
  16. Fulltext Mobile phone reminders and peer counseling improve adherence and treatment outcomes of patients on ART in Malaysia: A randomized clinical trial
    Abdulrahman SA, Rampal L, Ibrahim F, Radhakrishnan AP, Kadir Shahar H, Othman N
    PLoS One, 2017;12(5):e0177698.
    PMID: 28520768 DOI: 10.1371/journal.pone.0177698
    BACKGROUND: Adherence to treatment remains the cornerstone of long term viral suppression and successful treatment outcomes among patients receiving Antiretroviral Therapy (ART).

    OBJECTIVE(S): Evaluate the effectiveness of mobile phone reminders and peer counseling in improving adherence and treatment outcomes among HIV positive patients on ART in Malaysia.

    METHODS: A single-blind, parallel group RCT conducted in Hospital Sungai Buloh, Malaysia in which 242 adult Malaysian patients were randomized to intervention or control groups. Intervention consisted of a reminder module delivered through SMS and telephone call reminders by trained research assistants for 24 consecutive weeks (starting from date of ART initiation), in addition to adherence counseling at every clinic visit. The length of intended follow up for each patient was 6 months. Data on adherence behavior of patients was collected using specialized, pre-validated Adult AIDS Clinical Trial Group (AACTG) adherence questionnaires. Data on weight, clinical symptoms, CD4 count and viral load tests were also collected. Data was analyzed using SPSS version 22 and R software. Repeated measures ANOVA, Friedman's ANOVA and Multivariate regression models were used to evaluate efficacy of the intervention.

    RESULTS: The response rate after 6 months follow up was 93%. There were no significant differences at baseline in gender, employment status, income distribution and residential location of respondents between the intervention and control group. After 6 months follow up, the mean adherence was significantly higher in the intervention group (95.7; 95% CI: 94.39-96.97) as compared to the control group (87.5; 95% CI: 86.14-88.81). The proportion of respondents who had Good (>95%) adherence was significantly higher in the intervention group (92.2%) compared to the control group (54.6%). A significantly lower frequency in missed appointments (14.0% vs 35.5%) (p = 0.001), lower viral load (p = 0.001), higher rise in CD4 count (p = 0.017), lower incidence of tuberculosis (p = 0.001) and OIs (p = 0.001) at 6 months follow up, was observed among patients in the intervention group.

    CONCLUSION: Mobile phone reminders (SMS and telephone call reminders) and peer counseling are effective in improving adherence and treatment outcomes among HIV positive patients on ART in Malaysia. These findings may be of potential benefit for collaborative adherence planning between patients and health care providers at ART commencement.

  17. Fulltext Sociodemographic profile and predictors of outpatient clinic attendance among HIV-positive patients initiating antiretroviral therapy in Selangor, Malaysia
    Abdulrahman SA, Rampal L, Othman N, Ibrahim F, Hayati KS, Radhakrishnan AP
    Patient Prefer Adherence, 2017;11:1273-1284.
    PMID: 28794617 DOI: 10.2147/PPA.S141609
    BACKGROUND: Inconsistent literature evidence suggests that sociodemographic, economic, and system- and patient-related factors are associated with clinic attendance among the HIV-positive population receiving antiretroviral therapy (ART) around the world. We examined the factors that predict outpatient clinic attendance among a cohort of HIV-positive patients initiating ART in Selangor, Malaysia.

    PATIENTS AND METHODS: This cross-sectional study analyzed secondary data on outpatient clinic attendance and sociodemographic, economic, psychosocial, and patient-related factors among 242 adult Malaysian patients initiating ART in Selangor, Malaysia. Study cohort was enrolled in a parent randomized controlled trial (RCT) in Hospital Sungai Buloh Malaysia between January and December 2014, during which peer counseling, medication, and clinic appointment reminders were provided to the intervention group through short message service (SMS) and telephone calls for 24 consecutive weeks. Data on outpatient clinic attendance were extracted from the hospital electronic medical records system, while other patient-level data were extracted from pre-validated Adult AIDS Clinical Trial Group (AACTG) adherence questionnaires in which primary data were collected. Outpatient clinic attendance was categorized into binary outcome - regular attendee and defaulter categories - based on the number of missed scheduled outpatient clinic appointments within a 6-month period. Multivariate regression models were fitted to examine predictors of outpatient clinic attendance using SPSS version 22 and R software.

    RESULTS: A total of 224 (93%) patients who completed 6-month assessment were included in the model. Out of those, 42 (18.7%) defaulted scheduled clinic attendance at least once. Missed appointments were significantly more prevalent among females (n=10, 37.0%), rural residents (n=10, 38.5%), and bisexual respondents (n=8, 47.1%). Multivariate binary logistic regression analysis showed that Indian ethnicity (adjusted odds ratio [AOR] =0.235; 95% CI [0.063-0.869]; P=0.030) and heterosexual orientation (AOR =4.199; 95% CI [1.040-16.957]; P=0.044) were significant predictors of outpatient clinic attendance among HIV-positive patients receiving ART in Malaysia.

    CONCLUSION: Ethnicity and sexual orientation of Malaysian patients may play a significant role in their level of adherence to scheduled clinic appointments. These factors should be considered during collaborative adherence strategy planning at ART initiation.

    Study site: Outpatient clinic, Hospital Sungai Buloh Malaysia
  18. Fulltext Genetic analyses favour an ancient and natural origin of elephants on Borneo
    Sharma R, Goossens B, Heller R, Rasteiro R, Othman N, Bruford MW, et al.
    Sci Rep, 2018 01 17;8(1):880.
    PMID: 29343863 DOI: 10.1038/s41598-017-17042-5
    The origin of the elephant on the island of Borneo remains elusive. Research has suggested two alternative hypotheses: the Bornean elephant stems either from a recent introduction in the 17th century or from an ancient colonization several hundreds of thousands years ago. Lack of elephant fossils has been interpreted as evidence for a very recent introduction, whereas mtDNA divergence from other Asian elephants has been argued to favor an ancient colonization. We investigated the demographic history of Bornean elephants using full-likelihood and approximate Bayesian computation analyses. Our results are at odds with both the recent and ancient colonization hypotheses, and favour a third intermediate scenario. We find that genetic data favour a scenario in which Bornean elephants experienced a bottleneck during the last glacial period, possibly as a consequence of the colonization of Borneo, and from which it has slowly recovered since. Altogether the data support a natural colonization of Bornean elephants at a time when large terrestrial mammals could colonise from the Sunda shelf when sea levels were much lower. Our results are important not only in understanding the unique history of the colonization of Borneo by elephants, but also for their long-term conservation.
  19. Fulltext Effects of gamma irradiation on tropomyosin allergen, proximate composition and mineral elements in giant freshwater prawn (Macrobrachium rosenbergii)
    Muanghorn W, Konsue N, Sham H, Othman Z, Mohamed F, Mohd Noor N, et al.
    J Food Sci Technol, 2018 May;55(5):1960-1965.
    PMID: 29666550 DOI: 10.1007/s13197-018-3104-3
    Effects of food irradiation on allergen and nutritional composition of giant freshwater prawn are not well documented. Thus, this study aimed to investigate the effects of gamma irradiation on tropomyosin allergen, proximate composition, and mineral elements in Macrobrachium rosenbergii. In this study, prawn was peeled, cut into small pieces, vacuum packaged and gamma irradiated at 0, 5, 7, 10 and 15 kGy with a dose rate of 0.5 kGy/h using cobalt-60 as the source, subsequently determined the level of tropomyosin, proximate composition and mineral elements respectively. The results showed that band density of tropomyosin irradiated at 10 and 15 kGy is markedly decreased. Proximate analysis revealed that moisture, protein, and carbohydrate content were significantly different as compared with non-irradiated prawn. Meanwhile, gamma irradiated M. rosenbergii at 15 kGy was observed to be significantly higher in nickel and zinc than the non-irradiated prawn. The findings provide a new information that food irradiation may affect the tropomyosin allergen, proximate composition and mineral elements of the prawn.
  20. Fulltext Preparation and Characterization of Low-Molecular-Weight Natural Rubber Latex via Photodegradation Catalyzed by Nano TiO₂
    Ibrahim S, Othman N, Sreekantan S, Tan KS, Mohd Nor Z, Ismail H
    Polymers (Basel), 2018 Nov 01;10(11).
    PMID: 30961141 DOI: 10.3390/polym10111216
    Natural rubber is one of the most important renewable biopolymers used in many applications due to its special properties that cannot be easily mimicked by synthetic polymers. To sustain the existence of natural rubber in industries, modifications have been made to its chemical structure from time to time in order to obtain new properties and to enable it to be employed in new applications. The chemical structure of natural rubber can be modified by exposure to ultraviolet light to reduce its molecular weight. Under controlled conditions, the natural rubber chains will be broken by photodegradation to yield low-molecular-weight natural rubber. The aim of this work was to obtain what is known as liquid natural rubber via photodegradation, with titanium dioxide nanocrystals as the catalyst. Titanium dioxide, which was firstly synthesized using the sol⁻gel method, was confirmed to be in the form of an anatase, with a size of about 10 nm. In this work, the photodegradation was carried out in latex state and yielded low-molecular-weight natural rubber latex of less than 10,000 g/mol. The presence of hydroxyl and carbonyl groups on the liquid natural rubber (LNR) chains was observed, resulting from the breaking of the chains. Scanning electron microscopy of the NR latex particles showed that titanium dioxide nanocrystals were embedded on the latex surface, but then detached during the degradation reaction.
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