MyMedR

Displaying all 15 publications

Abstract:

Sort:

Readability and suitability of oral health education pamphlets produced by the Ministry of Health Malaysia

Wong ST, Saddki N, Tin-Oo MM

Med J Malaysia, 2019 08;74(4):312-319.
PMID: 31424039

INTRODUCTION: Printed health education materials can only be effective if they are readable and suitable for the target audience. This study examined the readability and suitability of oral health education (OHE) pamphlets produced by the Oral Health Program (OHP), Ministry of Health (MOH) Malaysia.
METHODS: The Khadijah Rohani's Readability Formula (KRRF) and Suitability Assessment of Materials (SAM) instrument were used to assess the readability and suitability of the pamphlets respectively. All 23 Bahasa Malaysia pamphlets retrieved from the official portal of OHP on the 31st January 2019 were assessed for suitability. However, only five pamphlets were found to be eligible for readability assessment because the KRRF, the single formula available for Bahasa Malaysia text is applicable only for materials with 300 words or more. The readability is interpreted based on the level of formal education in Malaysia.
RESULTS: All pamphlets achieved superior suitability rating with a minimum and maximum score of 75% and 95% respectively. However, a few pamphlets did not fulfil SAM superior and adequate criteria for the following factors and were rated not suitable: did not include summary (73.9%), have few or no headers (4.3%), did not use captions to explain graphics (17.4%), and did not provide interactive learning (21.7%). Readability of the pamphlets eligible for assessment ranged from primary six to secondary three.
CONCLUSIONS: OHE pamphlets produced by the MOH are readable by most Malaysians. Most pamphlets are generally suitable for the intended audience although a few performed poorly in several areas.
Fulltext Toll-like receptor 9 and 4 gene polymorphisms in susceptibility and severity of malaria: a meta-analysis of genetic association studies

Naing C, Wong ST, Aung HH

Malar J, 2021 Jul 03;20(1):302.
PMID: 34217314 DOI: 10.1186/s12936-021-03836-6

BACKGROUND: Malaria is still a major public health problem in sub-Saharan Africa and South-east Asia. The clinical presentations of malaria infection vary from a mild febrile illness to life-threatening severe malaria. Toll like receptors (TLRs) are postulated to be involved in the innate immune responses to malaria. Individual studies showed inconclusive findings. This study aimed to assess the role of TLR4 (D299G, T399I) and TLR9 (T1237C, T1486C) in severity or susceptibility of malaria by meta-analysis of data from eligible studies.
METHODS: Relevant case-control studies that assessed the association between TLR 4/9 and malaria either in susceptibility or progression were searched in health-related electronic databases. Quality of included studies was evaluated with Newcastle-Ottawa scale. Pooled analyses for specific genetic polymorphisms were done under five genetic models. Stratified analysis was done by age and geographical region (Asian countries vs non-Asian countries).
RESULTS: Eleven studies (2716 cases and 2376 controls) from nine endemic countries were identified. Five studies (45.4%) obtained high score in quality assessment. Overall, a significant association between TLR9 (T1486C) and severity of malaria is observed in allele model (OR: 1.26, 95% CI: 1.08-1.48, I2 = 0%) or homozygous model (OR: 1.55, 95% CI: 1.08-2.28, I2 = 0%). For TLR9 (T1237C), a significant association with severity of malaria is observed in in heterozygous model (OR:1.89, 95% CI: 1.11-3.22, I2 = 75%). On stratifications, TLR9 (T1486C) is only significantly associated with a subgroup of children of non-Asian countries under allele model (OR: 1.25, 95% CI: 1.02-1.38), while 1237 is with a subgroup of adults from Asian countries under heterozygous model (OR: 2.0, 95% CI: 1.09-3.64, I2 = 39%). Regarding the susceptibility to malaria, TLR9 (T1237C) is significantly associated only with the children group under recessive model (OR: 2.21, 95% CI: 1.06-4.57, I2=85%) and homozygous model (OR: 1.49, 95% CI: 1.09-2.0, I2 = 0%). For TLR4 (D299G, T399I), none is significantly associated with either severity of malaria or susceptibility to malaria under any genetic models.
CONCLUSIONS: The findings suggest that TLR 9 (T1486C and T1237C) seems to influence the progression of malaria, under certain genetic models and in specific age group of people from specific geographical region. TLR 9 (T1237C) also plays a role in susceptibility to malaria under certain genetic models and only with children of non-Asian countries. To substantiate these, future well designed studies with larger samples across endemic countries are needed.
Development of an optical biosensor for the detection of Trypanosoma evansi and Plasmodium berghei

Theint HT, Walsh JE, Wong ST, Voon K, Shitan M

Spectrochim Acta A Mol Biomol Spectrosc, 2019 Jul 05;218:348-358.
PMID: 31026712 DOI: 10.1016/j.saa.2019.04.008

A laboratory prototype system that correlates murine blood absorbance with degree of infection for Plasmodium berghei and Trypanosoma avensi has been designed, constructed and tested. A population (n = 6) of control uninfected, Plasmodium infected and Trypanosoma infected BALB/c mice were developed and spectral absorption measurements pre and post infection were made every 3 days. A fibre optic spectrometer set-up was used as the basis of a laboratory prototype biosensor that uses the Beer Lambert Law to relate Ultraviolet-Visible-Near-infrared absorbance data to changes in murine blood chemistry post infection. Spectral absorption results indicate a statistically relevant correlation at a 650 nm with infection for Plasmodium from between 4 and 7 sampling days' post infection, in spite of significant standard deviations among the sample populations for control and infected mice. No significant spectral absorption change for Trypanosoma infection was been detected from the current data. Corresponding stained slides of control and infected blood at each sampling date were taken with related infected cell counts determined and these correlate well for Plasmodium absorbance at 650 nm.
Habitat use by a primate community in a lowland dipterocarp forest in Danum Valley, Borneo

Hanya G, Kanamori T, Kuze N, Wong ST, Bernard H

Am J Primatol, 2020 08;82(8):e23157.
PMID: 32515849 DOI: 10.1002/ajp.23157

Knowledge of niche partitioning with respect to habitat is indispensable to understand the mechanism of coexistence of multiple species. Among primates, however, data are still deficient because repeated survey for a sufficiently long time, covering seasonal changes over a large area, is the only way to clarify habitat segregation within a seasonally fluctuating environment. Southeast Asia is particularly interesting because of the supra-annual, highly unpredictable seasonality in fruiting known as mast fruiting. We conducted repeated route census, habitat monitoring, and group tracking for 25 months in two study sites (ca. 10 km apart) in the largely primary lowland dipterocarp forest of the Danum Valley Conservation Area, eastern Sabah, northern Borneo, Malaysia. The five species of diurnal primates (Bornean orangutan Pongo pygmaeus, Müeller's gibbon Hylobates muelleri, red leaf monkey Presbytis rubicunda, long-tailed macaque Macaca fascicularis, and southern pig-tailed macaque M. nemestrina) did not show horizontal spatial segregation. Red leaf monkeys showed preferences for places with short tree height, but their distribution was not confined to such places. In response to the fruiting peak observed once during the study period, orangutans increased their numbers simultaneously in the two study sites. The average tree height used by the five species was different, but their range overlapped substantially. Compared with other primate communities, the lack of horizontal spatial segregation and the suggested long-distance movement of orangutans seem to be unique characteristics in Borneo, although the use of different forest strata is a widespread phenomenon among primate communities throughout the world.
Clinicopathological study of gastric cancer in a Malaysian tertiary public health care centre

Htet H, Win TT, Wong ST, Shamsudin NH, Kandasami P

Med J Malaysia, 2023 Sep;78(5):616-620.
PMID: 37775488

INTRODUCTION: Gastric cancer (GC) is one of the leading causes of all new cancer cases globally. Although it is no longer reported in the top 10th most common cancer in Malaysia, geographical distribution and ethnic influences still obviously exist.
MATERIALS AND METHODS: This is a retrospective analysis of histopathological records in a public tertiary health care centre in Malaysia. The computerised laboratory information system from the histopathology department of the hospital was retrieved for the period of 2005-2018. Descriptive analysis was done using Microsoft Excel.
RESULTS: There was a total of 233 histologically confirmed GC cases. The burden of GC was observed to be an increasing trend from 2016 onwards. Among them, 64% were male and 36% were female. The youngest age of diagnosis was 19, while the oldest one was 93. Malaysian Chinese were found to have the highest incidences (41.63%), followed by Malays (32.19%) and Malaysian Indians (23.61%). All cases were of adenocarcinoma cell types and were found to have poorly differentiated in majority at the time of diagnosis.
CONCLUSION: Although this report only represents one tertiary health care centre in Malaysia, the Indian Enigma was still observed, as stated in other literatures. Over time, the incidence of GC in Malays has increased. Consideration of lifestyle modifications, health education and Helicobacter pylori eradication in various nations' National Health Insurance plans, are encouraged as prevention is always better than treatment or cure, including the cost load.
Fulltext Pteropine Orthoreovirus (PRV7S) does not Establish Persistent Infection in NP460 Cells but with Inflammatory Response Triggered

Loh MKA, Siew ZY, Leong PP, Koh RY, Chye SM, Wong ST, et al.

Biomed Environ Sci, 2023 Sep 20;36(9):886-891.
PMID: 37803902 DOI: 10.3967/bes2023.114
Fulltext Antioxidant and toxicity studies of 50% methanolic extract of Orthosiphon stamineus Benth

Yam MF, Lim CP, Fung Ang L, Por LY, Wong ST, Asmawi MZ, et al.

Biomed Res Int, 2013;2013:351602.
PMID: 24490155 DOI: 10.1155/2013/351602

The present study evaluated the antioxidant activity and potential toxicity of 50% methanolic extract of Orthosiphon stamineus (Lamiaceae) leaves (MEOS) after acute and subchronic administration in rats. Superoxide radical scavenging, hydroxyl radical scavenging, and ferrous ion chelating methods were used to evaluate the antioxidant properties of the extract. In acute toxicity study, single dose of MEOS, 5000 mg/kg, was administered to rats by oral gavage, and the treated rats were monitored for 14 days. While in the subchronic toxicity study, MEOS was administered orally, at doses of 1250, 2500, and 5000 mg/kg/day for 28 days. From the results, MEOS showed good superoxide radical scavenging, hydroxyl radical scavenging, ferrous ion chelating, and antilipid peroxidation activities. There was no mortality detected or any signs of toxicity in acute and subchronic toxicity studies. Furthermore, there was no significant difference in bodyweight, relative organ weight, and haematological and biochemical parameters between both male and female treated rats in any doses tested. No abnormality of internal organs was observed between treatment and control groups. The oral lethal dose determined was more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of MEOS for both male and female rats is considered to be 5000 mg/kg per day.
Mitochondrial DNA Profiling Reveals Two Lineages of Sun Bears in East and West Malaysia

Lai WL, Chew J, Gatherer D, Ngoprasert D, Rahman S, Ayub Q, et al.

J Hered, 2021 03 29;112(2):214-220.
PMID: 33439997 DOI: 10.1093/jhered/esab004

Sun bear populations are fragmented and at risk from habitat loss and exploitation for body parts. These threats are made worse by significant gaps in knowledge of sun bear population genetic diversity, population connectivity, and taxonomically significant management units. Using a complete sun bear mitochondrial genome, we developed a set of mitochondrial markers to assess haplotype variation and the evolutionary history of sun bears from Peninsular (West) Malaysia and Sabah (East Malaysia). Genetic samples from 28 sun bears from Peninsular Malaysia, 36 from Sabah, and 18 from Thailand were amplified with primers targeting a 1800 bp region of the mitochondrial genome including the complete mitochondrial control region and adjacent genes. Sequences were analyzed using phylogenetic methods. We identified 51 mitochondrial haplotypes among 82 sun bears. Phylogenetic and network analyses provided strong support for a deep split between Malaysian sun bears and sun bears in East Thailand and Yunnan province in China. The Malaysian lineage was further subdivided into two clades: Peninsular Malaysian and Malaysian Borneo (Sabah). Sun bears from Thailand occurred in both Sabah and Peninsular Malaysian clades. Our study supports recent findings that sun bears from Sundaland form a distinct clade from those in China and Indochina with Thailand possessing lineages from the three clades. Importantly, we demonstrate a more recent and clear genetic delineation between sun bears from the Malay Peninsula and Sabah indicating historical barriers to gene flow within the Sundaic region.
Fulltext Dengue fever and insecticide resistance in Aedes mosquitoes in Southeast Asia: a review

Gan SJ, Leong YQ, Bin Barhanuddin MFH, Wong ST, Wong SF, Mak JW, et al.

Parasit Vectors, 2021 Jun 10;14(1):315.
PMID: 34112220 DOI: 10.1186/s13071-021-04785-4

Dengue fever is the most important mosquito-borne viral disease in Southeast Asia. Insecticides remain the most effective vector control approach for Aedes mosquitoes. Four main classes of insecticides are widely used for mosquito control: organochlorines, organophosphates, pyrethroids and carbamates. Here, we review the distribution of dengue fever from 2000 to 2020 and its associated mortality in Southeast Asian countries, and we gather evidence on the trend of insecticide resistance and its distribution in these countries since 2000, summarising the mechanisms involved. The prevalence of resistance to these insecticides is increasing in Southeast Asia, and the mechanisms of resistance are reported to be associated with target site mutations, metabolic detoxification, reduced penetration of insecticides via the mosquito cuticle and behavioural changes of mosquitoes. Continuous monitoring of the status of resistance and searching for alternative control measures will be critical for minimising any unpredicted outbreaks and improving public health. This review also provides improved insights into the specific use of insecticides for effective control of mosquitoes in these dengue endemic countries.
Bat coronavirus was detected positive from insectivorous bats in Krau Wildlife Reserve Forest

Siew ZY, Lai ZJ, Ho QY, Ter HC, Ho SH, Wong ST, et al.

Trop Biomed, 2023 Dec 01;40(4):462-470.
PMID: 38308834 DOI: 10.47665/tb.40.4.012

Bats are flying mammals with unique immune systems that allow them to hold many pathogens. Hence, they are recognised as the reservoir of many zoonotic pathogens. In this study, we performed molecular detection to detect coronaviruses, paramyxoviruses, pteropine orthoreoviruses and dengue viruses from samples collected from insectivorous bats in Krau Reserve Forest. One faecal sample from Rhinolophus spp. was detected positive for coronavirus. Based on BLASTN, phylogenetic analysis and pairwise alignment-based sequence identity calculation, the detected bat coronavirus is most likely to be a bat betacoronavirus lineage slightly different from coronavirus from China, Philippines, Thailand and Luxembourg. In summary, continuous surveillance of bat virome should be encouraged, as Krau Reserve Forest reported a wide spectrum of biodiversity of insectivorous and fruit bats. Moreover, the usage of primers for the broad detection of viruses should be reconsidered because geographical variations might possibly affect the sensitivity of primers in a molecular approach.
Fulltext A novel strategy for community screening of SARS-CoV-2 (COVID-19): Sample pooling method

Lim KL, Johari NA, Wong ST, Khaw LT, Tan BK, Chan KK, et al.

PLoS One, 2020;15(8):e0238417.
PMID: 32857823 DOI: 10.1371/journal.pone.0238417

The rapid global spread of the coronavirus disease (COVID-19) has inflicted significant health and socioeconomic burden on affected countries. As positive cases continued to rise in Malaysia, public health laboratories experienced an overwhelming demand for COVID-19 screening. The confirmation of positive cases of COVID-19 has solely been based on the detection of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) using real-time reverse transcription polymerase chain reaction (qRT-PCR). In efforts to increase the cost-effectiveness and efficiency of COVID-19 screening, we evaluated the feasibility of pooling clinical Nasopharyngeal/Oropharyngeal (NP/OP) swab specimens during nucleic acid extraction without a reduction in sensitivity of qRT-PCR. Pools of 10 specimens were extracted and subsequently tested by qRT-PCR according to the WHO-Charité protocol. We demonstrated that the sample pooling method showed no loss of sensitivity. The effectiveness of the pooled testing strategy was evaluated on both retrospective and prospective samples, and the results showed a similar detection sensitivity compared to testing individual sample alone. This study demonstrates the feasibility of using a pooled testing strategy to increase testing capacity and conserve resources, especially when there is a high demand for disease testing.
Fulltext COVID-19 Sample Pooling: From RNA Extraction to Quantitative Real-time RT-PCR

Voon K, Johari NA, Lim KL, Wong ST, Khaw LT, Wong SF, et al.

Bio Protoc, 2021 May 05;11(9):e4005.
PMID: 34124305 DOI: 10.21769/BioProtoc.4005

The COVID-19 pandemic requires mass screening to identify those infected for isolation and quarantine. Individually screening large populations for the novel pathogen, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is costly and requires a lot of resources. Sample pooling methods improve the efficiency of mass screening and consume less reagents by increasing the capacity of testing and reducing the number of experiments performed, and are therefore especially suitable for under-developed countries with limited resources. Here, we propose a simple, reliable pooling strategy for COVID-19 testing using clinical nasopharyngeal (NP) and/or oropharyngeal (OP) swabs. The strategy includes the pooling of 10 NP/OP swabs for extraction and subsequent testing via quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR), and may also be applied to the screening of other pathogens.
Seroprevalence of Pteropine orthoreovirus in humans remain similar after nearly two decades (2001-2002 vs. 2017) in Tioman Island, Malaysia

Leong WJ, Quek XF, Tan HY, Wong KM, Muhammad HS, Mohamed NA, et al.

J Med Virol, 2022 02;94(2):771-775.
PMID: 34708881 DOI: 10.1002/jmv.27422

Pteropine orthoreovirus (PRV) is an emerging zoonotic respiratory virus that can be transmitted from bats to humans. In Malaysia, aside from PRV2P (Pulau virus) being isolated from Pteropus hypomelanus sampled in Tioman Island, PRV3M (Melaka virus), PRV4K (Kampar virus), and PRV7S (Sikamat virus) were all isolated from samples of patients who reported having a disease spectrum from acute respiratory distress to influenza-like illness and sometimes even with enteric symptoms such as diarrhea and abdominal pain. Screening of sera collected from human volunteers on Tioman Island in 2001-2002 demonstrated that 12.8% (14/109) were positive for PRV2P and PRV3M. Taking all these together, we aim to investigate the serological prevalence of PRV (including PRV4K and PRV7S) among Tioman Island inhabitants again with the assumption that the seroprevalence rate will remain nearly similar to the above reported if human exposure to bats is still happening in the island. Using sera collected from human volunteers on the same island in 2017, we demonstrated seroprevalence of 17.8% (28/157) against PRV2P and PRV3M, respectively. Seropositivity of 11.4% among Tioman Island inhabitants against PRV4K and PRV7S, respectively, was described in this study. In addition, the seroprevalence of 89.5% (17/19), 73.6% (14/19), 63.0% (12/19), and 73.6% (14/19) against PRV2P, PRV3M, PRV4K, and PRV7S, respectively, were observed among pteropid bats in the island. We revealed that the seroprevalence of PRV among island inhabitants remains nearly similar after nearly two decades, suggesting that potential spill-over events in bat-human interface areas in the Tioman Island. We are unclear whether such spillover was directly from bats to humans, as suspected for the PRV3M human cases, or from an intermediate host(s) yet to be identified. There is a high possibility of the viruses circulating among the bats as demonstrated by high seroprevalence against PRV in the bats.
Fulltext Habitat degradation and indiscriminate hunting differentially impact faunal communities in the Southeast Asian tropical biodiversity hotspot

Tilker A, Abrams JF, Mohamed A, Nguyen A, Wong ST, Sollmann R, et al.

Commun Biol, 2019;2:396.
PMID: 31701025 DOI: 10.1038/s42003-019-0640-y

Habitat degradation and hunting have caused the widespread loss of larger vertebrate species (defaunation) from tropical biodiversity hotspots. However, these defaunation drivers impact vertebrate biodiversity in different ways and, therefore, require different conservation interventions. We conducted landscape-scale camera-trap surveys across six study sites in Southeast Asia to assess how moderate degradation and intensive, indiscriminate hunting differentially impact tropical terrestrial mammals and birds. We found that functional extinction rates were higher in hunted compared to degraded sites. Species found in both sites had lower occupancies in the hunted sites. Canopy closure was the main predictor of occurrence in the degraded sites, while village density primarily influenced occurrence in the hunted sites. Our findings suggest that intensive, indiscriminate hunting may be a more immediate threat than moderate habitat degradation for tropical faunal communities, and that conservation stakeholders should focus as much on overhunting as on habitat conservation to address the defaunation crisis.
Human cytokeratin 1 plays a role in the interaction of Pteropine orthoreovirus with Hek293 cells but not HeLa cells

Siew ZY, Tan YF, Iswara RP, Wong SF, Wong ST, Tan BK, et al.

Microbes Infect, 2024;26(1-2):105243.
PMID: 38380604 DOI: 10.1016/j.micinf.2023.105243

Pteropine orthoreovirus (PRV) causes respiratory tract infections in humans. Despite its emergence as a zoonotic and respiratory virus, little is known about its cell tropism, which hampers progress in fully understanding its pathogenesis in humans. Hek293 cells are most susceptible to PRV infection, while HeLa cells are the least. Human cytokeratin 1 (CK1) was identified as the protein that interacts with PRV. The immunofluorescence assay and qPCR results revealed prior treatment with anti-CK1 may provide Hek293 cells protection against PRV. The KRT1-knockout Hek293 cells were less susceptible to PRV infection. Further study into the pathogenesis of PRV in humans is needed.

Filters

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

External Links