Displaying publications 1 - 20 of 97 in total

Abstract:
Sort:
  1. microRNAs expression profiles in Schistosoma japonicum of different sex 14 and 28 days post-infection
    Ai L, Hu W, Zhang RL, Huang DN, Chen SH, Xu B, et al.
    Trop Biomed, 2020 Dec 01;37(4):947-962.
    PMID: 33612748 DOI: 10.47665/tb.37.4.947
    Different miRNAs are involved in the life cycles of Schistosoma japonicum. The aim of this study was to examine the expression profile of miRNAs in individual S. japonicum of different sex before and after pairing (18 and 24 dpi). The majority of differential expressed miRNAs were highly abundant at 14 dpi, except for sja-miR-125b and sja-miR-3505, in both male and female. Moreover, it was estimated that sja-miR-125b and sja-miR-3505 might be related to laying eggs. sja-miR-2a-5p and sja-miR-3484-5p were expressed at 14 dpi in males and were significantly clustered in DNA topoisomerase III, Rap guanine nucleotide exchange factor 1 and L-serine/L-threonine ammonia-lyase. Target genes of sja-miR-2d-5p, sja-miR-31- 5p and sja-miR-125a, which were expressed at 14 dpi in males but particularly females, were clustered in kelch-like protein 12, fructose-bisphosphate aldolase, class I, and heat shock protein 90 kDa beta. Predicted target genes of sja-miR-3483-3p (expressed at 28 dpi in females but not in males) were clustered in 26S proteasome regulatory subunit N1, ATPdependent RNA helicase DDX17. Predicted target genes of sja-miR-219-5p, which were differentially expressed at 28 dpi in females but particularly males, were clustered in DNA excision repair protein ERCC-6, protein phosphatase 1D, and ATPase family AAA domaincontaining protein 3A/B. Moreover, at 28 dpi, eight miRNAs were significantly up-regulated in females compared to males. The predicted target genes of these miRNAs were significantly clustered in heat shock protein 90 kDa beta, 26S proteasome regulatory subunit N1, and protein arginine N-methyltransferase 1. To sum up, differentially expressed miRNAs may have an essential role and provide necessary information on clarifying this trematode's growth, development, maturation, and infection ability to mammalian hosts in its complex life cycle, and may be helpful for developing new drug targets and vaccine candidates for schistosomiasis.
  2. Fulltext Whole-transcriptome sequencing identifies a distinct subtype of acute lymphoblastic leukemia with predominant genomic abnormalities of EP300 and CREBBP
    Qian M, Zhang H, Kham SK, Liu S, Jiang C, Zhao X, et al.
    Genome Res, 2017 02;27(2):185-195.
    PMID: 27903646 DOI: 10.1101/gr.209163.116
    Chromosomal translocations are a genomic hallmark of many hematologic malignancies. Often as initiating events, these structural abnormalities result in fusion proteins involving transcription factors important for hematopoietic differentiation and/or signaling molecules regulating cell proliferation and cell cycle. In contrast, epigenetic regulator genes are more frequently targeted by somatic sequence mutations, possibly as secondary events to further potentiate leukemogenesis. Through comprehensive whole-transcriptome sequencing of 231 children with acute lymphoblastic leukemia (ALL), we identified 58 putative functional and predominant fusion genes in 54.1% of patients (n = 125), 31 of which have not been reported previously. In particular, we described a distinct ALL subtype with a characteristic gene expression signature predominantly driven by chromosomal rearrangements of the ZNF384 gene with histone acetyltransferases EP300 and CREBBP ZNF384-rearranged ALL showed significant up-regulation of CLCF1 and BTLA expression, and ZNF384 fusion proteins consistently showed higher activity to promote transcription of these target genes relative to wild-type ZNF384 in vitro. Ectopic expression of EP300-ZNF384 and CREBBP-ZNF384 fusion altered differentiation of mouse hematopoietic stem and progenitor cells and also potentiated oncogenic transformation in vitro. EP300- and CREBBP-ZNF384 fusions resulted in loss of histone lysine acetyltransferase activity in a dominant-negative fashion, with concomitant global reduction of histone acetylation and increased sensitivity of leukemia cells to histone deacetylase inhibitors. In conclusion, our results indicate that gene fusion is a common class of genomic abnormalities in childhood ALL and that recurrent translocations involving EP300 and CREBBP may cause epigenetic deregulation with potential for therapeutic targeting.
  3. Weight and height curves for Malaysian schoolchildren
    Chen ST, Dugdale AE
    Med J Malaya, 1970 Dec;25(2):99-101.
    PMID: 4251142
  4. Fulltext Validation of the Geriatric Oral Health Assessment Index (GOHAI) in the Malay language
    Othman WN, Muttalib KA, Bakri R, Doss JG, Jaafar N, Salleh NC, et al.
    J Public Health Dent, 2006;66(3):199-204.
    PMID: 16913247 DOI: 10.1111/j.1752-7325.2006.tb02580.x
    Objective: To translate and validate the Geriatric Oral Health Assessment Index (GOHAI into the Malay language for use in Malaysia.

    Methodology: The 6-Likert scale GOHAI was translated into the Malay language and self-administered on 189 subjects aged 60+. All subjects underwent oral status assessment. The measure was assessed for construct and discriminant validity, for test-retest reliability and principal component factor.

    Findings: Mean GOHAI score was 46.2 (SD 9.7, range 17-60). The Cronbach's alpha was 0.79. Mean GOHAI scores increased with more positive self-rated oral health and general health. The elderly with no perceived dental treatment need had higher mean GOHAI scores than those with perceived needs. There were slightly stronger inverse correlations between GOHAI scores and caries experience, number of teeth present, and number of pathologically mobile teeth. The measure demonstrated strong test-retest reliability. Eight of the 12 items had Spearman's r3 0.7. Only one principal factor was found at eigenvalue > 1. Using ANCOVA, self-rated perception of oral health and perceived need for dental treatment had the most significant impact on the GOHAI score.

    Conclusion and recommendations: The Malay language version of the GOHAI demonstrated acceptable validity and reliability and will be an important instrument to measure oral health-related quality of life among Malay-speaking Malaysians. Use of the Malay language version GOHAI should also be pursued among diverse adult age groups.
  5. Fulltext Validation of a multiplex RT-PCR assay for screening significant oncogene fusion transcripts in children with acute lymphoblastic leukaemia
    Ariffin H, Chen SP, Wong HL, Yeoh A
    Singapore Med J, 2003 Oct;44(10):517-20.
    PMID: 15024455
    In childhood acute lymphoblastic leukaemia (ALL), cytogenetics play an important role in diagnosis, allocation of treatment and prognosis. Conventional cytogenetic analysis, involving mainly karyotyping in our experience, has not been successful in a large proportion of cases due to inadequate metaphase spreads and poor chromosome morphology. Our aim is to develop a highly sensitive and specific method to screen simultaneously for the four most frequent fusion transcripts resulting from specific chromosomal translocations, namely, both the CML- and ALLtype BCR-ABL transcripts of t(9;22), E2A-PBX1 transcript of t(1;19), the MLL-AF4 transcript of t(4;11) and TEL-AML1 (also termed ETV6-CBFA2) of the cryptic t(12;21). A multiplex reverse transcription polymerase chain reaction protocol (RT-PCR) was developed and tested out on archival bone marrow samples and leukaemia cell lines. In all samples with a known translocation detected by cytogenetic techniques, the same translocation was identified by the multiplex-PCR assay. Multiplex RT-PCR assay is an effective, sensitive, accurate and cost-effective diagnostic tool which can improve our ability to accurately and rapidly risk-stratify patients with childhood ALL.
  6. Fulltext Using the 2020 global pandemic as a springboard to highlight the need for amphibian conservation in eastern Asia
    Borzée A, Kielgast J, Wren S, Angulo A, Chen S, Magellan K, et al.
    Biol Conserv, 2021 Mar;255:108973.
    PMID: 35125500 DOI: 10.1016/j.biocon.2021.108973
    Emerging infectious diseases are on the rise in many different taxa, including, among others, the amphibian batrachochytrids, the snake fungal disease and the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) virus, responsible for Coronavirus disease 2019 (COVID-19) in mammals. Following the onset of the pandemic linked to COVID-19, eastern Asia has shown strong leadership, taking actions to regulate the trade of potential vector species in several regions. These actions were taken in response to an increase in public awareness, and the need for a quick reaction to mitigate against further pandemics. However, trade restrictions rarely affect amphibians, despite the risk of pathogen transmission, directly, or indirectly through habitat destruction and the loss of vector consumption. Thus, species that help alleviate the risk of zoonoses or provide biological control are not protected. Hence, in view of the global amphibian decline and the risk of zoonoses, we support the current wildlife trade regulations and support measures to safeguard wildlife from overexploitation. The current period of regulation overhaul should be used as a springboard for amphibian conservation. To mitigate risks, we suggest the following stipulations specifically for amphibians. I) Restrictions to amphibian farming in eastern Asia, in relation to pathogen transmission and the establishment of invasive species. II) Regulation of the amphibian pet trade, with a focus on potential vector species. III) Expansion of the wildlife trade ban, to limit the wildlife-human-pet interface. The resulting actions will benefit both human and wildlife populations, as they will lead to a decrease in the risk of zoonoses and better protection of the environment.

    Significance statement: There is an increasing number of emerging infectious diseases impacting all species, including amphibians, reptiles and mammals. The latest threat to humans is the virus responsible for COVID-19, and the resulting pandemic. Countries in eastern Asia have taken steps to regulate wildlife trade and prevent further zoonoses thereby decreasing the risk of pathogens arising from wild species. However, as amphibians are generally excluded from regulations we support specific trade restrictions: I) Restrictions to amphibian farming; II) regulation of the amphibian pet trade; III) expansion of the wildlife trade ban. These restrictions will benefit both human and wildlife populations by decreasing the risks of zoonoses and better protecting the environment.

  7. Fulltext Timing of antenatal tetanus immunization for effective protection of the neonate
    Chen ST, Edsall G, Peel MM, Sinnathuray TA
    Bull World Health Organ, 1983;61(1):159-65.
    PMID: 6601539
    The relationship between the timing of maternal tetanus toxoid immunization and the presence of protective antitoxin in placental cord blood was investigated among women admitted to the obstetrical service of the University Hospital in Kuala Lumpur, Malaysia. The 1st dose was given between 13-39 weeks of gestation, with a median of 29 weeks. The 2nd dose was given an average of 4 weeks later. Protection was conferred on 80% or more of newborns whose mothers received their 1st tetanus toxoid injection 60 days or more before delivery. Protective levels were seen in all cord blood samples from infants whose mothers had received their 1st injection 90 days before delivery. Similarly,protective titers were found in 100% of cord blood samples when the 2nd maternal injection was give 60 days or more before delivery. There was no significant degree of protection when immunization was carried out less than 20 days before delivery. A single-dose schedule provided no protection when less than 70 days before delivery. Cord and maternal antiotoxin titers differed by no more than 1 2-fold dilution for almost all of the individual paired sera. A cord: maternal antitoxin ratio of 2 was more likely to occur with increasing time between the 2nd injection and delivery. Overall, these findings indicate that the 1st injection of a 2-dose maternal tetanus toxoid schedule should be given at least 60 days and preferably 90 days before delivery.
  8. The sensitivity of staphylococci to antibiotics
    Puthucheary SD, Chen ST, Dugdale AE
    Med J Malaya, 1972 Jun;26(4):262-5.
    PMID: 5069415
  9. The mediating role of Internet addiction in depression, social anxiety, and psychosocial well-being among adolescents in six Asian countries: a structural equation modelling approach
    Lai CM, Mak KK, Watanabe H, Jeong J, Kim D, Bahar N, et al.
    Public Health, 2015 Sep;129(9):1224-36.
    PMID: 26343546 DOI: 10.1016/j.puhe.2015.07.031
    OBJECTIVES: This study examines the associations of Internet addiction with social anxiety, depression, and psychosocial well-being among Asian adolescents. A self-medication model conceptualizing Internet addiction as a mediating role in relating depression and social anxiety to negative psychosocial well-being was tested.
    STUDY DESIGN: A cross-sectional survey.
    METHODS: In the Asian Adolescent Risk Behavior Survey (AARBS), 5366 adolescents aged 12-18 years from six Asian countries (China, Hong Kong, Japan, South Korea, Malaysia, and Philippines) completed a questionnaire with items of the Internet Addiction Test (IAT), Social Anxiety Scale for Adolescents (SAS-A), Center for Epidemiological Studies Depression Scale (CESD), Self-Rated Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA-SR) in the 2012-2013 school year. Structural equation modelling was used to examine the mediating role of Internet addiction in depression, social anxiety, and subjective psychosocial well-being.
    RESULTS: Significant differences on the scores of IAT, SAS-A, CESD, and HoNOSCA-SR across the six countries were found. The proposed self-medication model of Internet addiction received satisfactory goodness-of-fit with data of all countries. After the path from social anxiety to Internet addiction had been discarded in the revised model, there was a significant improvement of the goodness-of-fit in the models for Japan, South Korea, and the Philippines.
    CONCLUSIONS: Depression and social anxiety reciprocally influenced, whereas depression associated with poorer psychosocial well-being directly and indirectly through Internet addiction in all six countries. Internet addiction mediated the association between social anxiety and poor psychosocial well-being in China, Hong Kong, and Malaysia.
    KEYWORDS: Adolescents; Asian; Depression; Internet addiction; Social anxiety; Structural equation modelling
  10. The improvement of immunization coverage by early immunisation of children in Malaysia
    Chen ST
    Med J Malaysia, 1976 Sep;31(1):17-9.
    PMID: 1023007
  11. The early immunisation of infants in Malaysia
    Chen ST, Choong MM
    Med J Malaya, 1971 Sep;26(1):15-9.
    PMID: 4258569
  12. The combined action of biochar and nitrogen-fixing bacteria on microbial and enzymatic activities of soil N cycling
    Gou Z, Zheng H, He Z, Su Y, Chen S, Chen H, et al.
    Environ Pollut, 2023 Jan 15;317:120790.
    PMID: 36460190 DOI: 10.1016/j.envpol.2022.120790
    This study aims to investigate the positive effects of the combined use of Enterobacter cloacae and biochar on improving nitrogen (N) utilization. The greenhouse pots experimental results showed the synergy of biochar and E. cloacae increased soil total N content and plant N uptake by 33.54% and 15.1%, respectively. Soil nitrogenase (NIT) activity increased by 253.02%. Ammonia monooxygenase (AMO) and nitrate reductase (NR) activity associated with nitrification and denitrification decreased by 10.94% and 29.09%, respectively. The relative abundance of N fixing microorganisms like Burkholderia and Bradyrhizobium significantly increased. Sphingomonas and Ottowia, two bacteria involved in the nitrification and denitrification processes, were found to be in lower numbers. The E. cloacae's ability to fix N2 and promote the growth of plants allow the retention of N in soil and make more N available for plant development. Biochar served as a reservoir of N for plants by adsorbing N from the soil and providing a shelter for E. cloacae. Thus, biochar and E. cloacae form a synergy for the management of agricultural N and the mitigation of negative impacts of pollution caused by excessive use of N fertilizer.
  13. Fulltext The FLUXNET2015 dataset and the ONEFlux processing pipeline for eddy covariance data
    Pastorello G, Trotta C, Canfora E, Chu H, Christianson D, Cheah YW, et al.
    Sci Data, 2020 07 09;7(1):225.
    PMID: 32647314 DOI: 10.1038/s41597-020-0534-3
    The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-filled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the first time in this paper. In addition, 206 of these sites are for the first time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible.
  14. Tetanus neonatorum in West Malaysia
    Chen ST
    J Trop Med Hyg, 1974 Sep;77(9):204-7.
    PMID: 4416077
  15. Fulltext Study protocol for an open labelled randomised controlled trial of perioperative oral nutrition supplement in breast and colorectal cancer patients undergoing elective surgery
    Wong TX, Chen ST, Ong SH, Shyam S, Kandasami P, Chee WSS
    Trials, 2021 Nov 03;22(1):767.
    PMID: 34732233 DOI: 10.1186/s13063-021-05716-5
    BACKGROUND: While it is well established that perioperative use of oral nutrition supplement (ONS) improves nutrition status among severely malnourished surgical cancer patients, the evidence requires further substantiation for non-severely malnourished patients with cancer. This protocol paper presents the rationale and design of a randomised controlled trial to evaluate the effectiveness of preoperative as well as an extended 90-day postoperative use of ONS on nutritional and clinical outcomes among patients undergoing elective surgery for breast and colorectal cancer.

    METHODS: Patients with primary breast and colorectal cancer undergoing elective surgery are recruited from two tertiary hospitals. Eligible patients are assigned into one of the three intervention arms: (i) Group SS will receive ONS in addition to their normal diet up to 14 days preoperatively and postoperatively up to discharge; (ii) Group SS-E will receive ONS in addition to their normal diet up to 14 days preoperatively, postoperatively up to discharge and for an extended 90 days after discharge; and (iii) Group DS will receive ONS in addition to their normal diet postoperatively up to discharge from the hospital. The ONS is a standard formula fortified with lactium to aid in sleep for recovery. The primary endpoints include changes in weight, body mass index (BMI), serum albumin and prealbumin levels, while secondary endpoints are body composition (muscle and fat mass), muscle strength (handgrip strength), energy and protein intake, sleep quality, haemoglobin, inflammatory markers (transferrin, high sensitivity C-reactive protein, interleukin-6), stress marker (saliva cortisol), length of hospital stay and postoperative complication rate.

    DISCUSSION: This trial is expected to provide evidence on whether perioperative supplementation in breast and colorectal cancer patients presenting with high BMI and not severely malnourished but undergoing the stress of surgery would be beneficial in terms of nutritional and clinical outcomes.

    TRIAL REGISTRATION: ClinicalTrial.gov NCT04400552. Registered on 22 May 2020, retrospectively registered.

  16. Standards for subcutaneous fat and arm circumference in Malaysian school children
    Chen ST
    J Singapore Paediatr Soc, 1977 Jun;19(2):97-100.
    PMID: 916636
  17. Some epidemiological aspects of diphtheria in Malaysia
    Chen ST, Puthucheary SD
    Trop Geogr Med, 1976 Sep;28(3):211-5.
    PMID: 1006789
    In Malysia, the proportion of children fully immunized againest diphtheria is generally low (20%). On the other hand, the Schick conversion rate rises with age and reaches 90% by 11 years of age. It is noted that asymptomatic carriers are an important epidemiological factor in diphtheria and that carrier rates for school children are high (prevalence of 7.5% while the rate of coloization with C. diphtheriae over a period of one year was 30%). Although immunization protects against clinical diphtheria, it does not prevent the carrier state. Thus, for the control of diphtheria, one should aim for 100% compliance. Some suggestions as to how higher levels of immunity may be achieved are described.
  18. Fulltext Silver nanoparticles reduce brain inflammation and related neurotoxicity through induction of H2S-synthesizing enzymes
    Gonzalez-Carter DA, Leo BF, Ruenraroengsak P, Chen S, Goode AE, Theodorou IG, et al.
    Sci Rep, 2017 03 02;7:42871.
    PMID: 28251989 DOI: 10.1038/srep42871
    Silver nanoparticles (AgNP) are known to penetrate into the brain and cause neuronal death. However, there is a paucity in studies examining the effect of AgNP on the resident immune cells of the brain, microglia. Given microglia are implicated in neurodegenerative disorders such as Parkinson's disease (PD), it is important to examine how AgNPs affect microglial inflammation to fully assess AgNP neurotoxicity. In addition, understanding AgNP processing by microglia will allow better prediction of their long term bioreactivity. In the present study, the in vitro uptake and intracellular transformation of citrate-capped AgNPs by microglia, as well as their effects on microglial inflammation and related neurotoxicity were examined. Analytical microscopy demonstrated internalization and dissolution of AgNPs within microglia and formation of non-reactive silver sulphide (Ag2S) on the surface of AgNPs. Furthermore, AgNP-treatment up-regulated microglial expression of the hydrogen sulphide (H2S)-synthesizing enzyme cystathionine-γ-lyase (CSE). In addition, AgNPs showed significant anti-inflammatory effects, reducing lipopolysaccharide (LPS)-stimulated ROS, nitric oxide and TNFα production, which translated into reduced microglial toxicity towards dopaminergic neurons. Hence, the present results indicate that intracellular Ag2S formation, resulting from CSE-mediated H2S production in microglia, sequesters Ag+ ions released from AgNPs, significantly limiting their toxicity, concomitantly reducing microglial inflammation and related neurotoxicity.
  19. Fulltext Sex differences in dementia risk and risk factors: Individual-participant data analysis using 21 cohorts across six continents from the COSMIC consortium
    Gong J, Harris K, Lipnicki DM, Castro-Costa E, Lima-Costa MF, Diniz BS, et al.
    Alzheimers Dement, 2023 Aug;19(8):3365-3378.
    PMID: 36790027 DOI: 10.1002/alz.12962
    INTRODUCTION: Sex differences in dementia risk, and risk factor (RF) associations with dementia, remain uncertain across diverse ethno-regional groups.

    METHODS: A total of 29,850 participants (58% women) from 21 cohorts across six continents were included in an individual participant data meta-analysis. Sex-specific hazard ratios (HRs), and women-to-men ratio of hazard ratios (RHRs) for associations between RFs and all-cause dementia were derived from mixed-effect Cox models.

    RESULTS: Incident dementia occurred in 2089 (66% women) participants over 4.6 years (median). Women had higher dementia risk (HR, 1.12 [1.02, 1.23]) than men, particularly in low- and lower-middle-income economies. Associations between longer education and former alcohol use with dementia risk (RHR, 1.01 [1.00, 1.03] per year, and 0.55 [0.38, 0.79], respectively) were stronger for men than women; otherwise, there were no discernible sex differences in other RFs.

    DISCUSSION: Dementia risk was higher in women than men, with possible variations by country-level income settings, but most RFs appear to work similarly in women and men.

  20. Sensitivity of Staphylococci to antibiotics
    Puthucheary SD, Chen ST, Dugdale AE
    Med J Malaysia, 1972 Jun;26(4):262-265.
    PMID: 35158504
    No abstract available.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links