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Fulltext Mast cell stabilizing effect of a geranyl acetophenone in dengue virus infection using in vitro model of DENV3-induced RBL-2H3 cells

Tan JW, Wan Zahidi NF, Kow ASF, Soo KM, Shaari K, Israf DA, et al.

Biosci Rep, 2019 06 28;39(6).
PMID: 31110077 DOI: 10.1042/BSR20181273

Mast cells (MCs), a type of immune effector cell, have recently become recognized for their ability to cause vascular leakage during dengue virus (DENV) infection. Although MC stabilizers have been reported to attenuate DENV induced infection in animal studies, there are limited in vitro studies on the use of MC stabilizers against DENV induced MC degranulation. 2,4,6-trihydroxy-3-geranyl acetophenone (tHGA) has been reported to be a potential MC stabilizer by inhibiting IgE-mediated MC activation in both cellular and animal models. The present study aims to establish an in vitro model of DENV3-induced RBL-2H3 cells using ketotifen fumarate as a control drug, as well as to determine the effect of tHGA on the release of MC mediators upon DENV infection. Our results demonstrated that the optimal multiplicities of infection (MOI) were 0.4 × 10-2 and 0.8 × 10-2 focus forming units (FFU)/cell. Ketotifen fumarate was proven to attenuate DENV3-induced RBL-2H3 cells degranulation in this in vitro model. In contrast, tHGA was unable to attenuate the release of both β-hexosaminidase and tumor necrosis factor (TNF)-α. Nonetheless, our study has successfully established an in vitro model of DENV3-induced RBL-2H3 cells, which might be useful for the screening of potential MC stabilizers for anti-dengue therapies.
Species composition and toxicity of the genus Pseudo-nitzschia in Taiwan Strait, including P. chiniana sp. nov. and P. qiana sp. nov

Huang CX, Dong HC, Lundholm N, Teng ST, Zheng GC, Tan ZJ, et al.

Harmful Algae, 2019 Apr;84:195-209.
PMID: 31128805 DOI: 10.1016/j.hal.2019.04.003

In a field survey in the Taiwan Strait during April 2016, the species composition and the domoic acid production of the diatom genus Pseudo-nitzschia were investigated. A total of 80 strains of Pseudo-nitzschia were established, and species identification was determined based on a combination of morphological and molecular data. Fourteen taxa were recognized, i.e., P. americana, P. brasiliana, P. calliantha, P. cuspidata, P. galaxiae, P. lundholmiae, P. multiseries, P. multistriata, P. pseudodelicatissima, P. pungens var. aveirensis, P. pungenus var. pungens and P. sabit, as well as two novel species P. chiniana C.X. Huang & Yang Li and P. qiana C.X. Huang & Yang Li. Morphologically, P. chiniana is characterized by striae comprising one or two rows of poroids, and valve ends that are normally dominated by two rows of poroids within each stria. Whereas P. qiana is unique by having a narrow valve width (1.3-1.5 μm) and sharply pointed valve ends. Both taxa constitute their own monophyletic lineage in the phylogenetic analyses inferred from LSU and ITS2 rDNA, and are well differentiated from other Pseudo-nitzschia species. Pseudo-nitzschia chiniana forms a group with P. abrensis and P. batesiana in LSU and ITS trees, whereas P. qiana is sister to P. lineola. When comparing ITS2 secondary structure, five CBCs and seven HCBCs are recognized between P. chiniana and P. abrensis, and four CBCs and ten HCBCs between P. chiniana and P. batesiana. Two CBCs and eight HCBCs are found between P. qiana with P. lineola. The ability of the strains to produce domoic acid was assessed, including a potential toxin induction by the presence of brine shrimps. Results revealed production of domoic acid in six strains belonging to three species. Without presence of brine shrimps, cellular DA (pDA) was detected in four P. multiseries strains (1.6 ± 0.3, 26.6 ± 2.7, 68.3 ± 4.2 and 56.9 ± 4.7 fg cell-1, separately), one strain of P. pseudodelicatissima (0.8 ± 0.2 fg cell-1) and one strain of P. lundholmiae (2.5 ± 0.4 fg cell-1). In the presence of brine shrimps, pDA contents increased significantly (p
Experimental assessment on feasibility of computed tomography-based thermometry for radiofrequency ablation on tissue equivalent polyacrylamide phantom

Tan D, Mohamad NA, Wong YH, Yeong CH, Cheah PL, Sulaiman N, et al.

Int J Hyperthermia, 2019;36(1):554-561.
PMID: 31132888 DOI: 10.1080/02656736.2019.1610800

Purpose: This study aimed to evaluate the effects of various computed tomography (CT) acquisition parameters and metal artifacts on CT number measurement for CT thermometry during CT-guided thermal ablation. Methods: The effects of tube voltage (100-140 kVp), tube current (20-250 mAs), pitch (0.6-1.5) and gantry rotation time (0.5, 1.0 s) as well as metal artifacts from a radiofrequency ablation (RFA) needle on CT number were evaluated using liver tissue equivalent polyacrylamide (PAA) phantom. The correlation between CT number and temperature from 37 to 80 °C was studied on PAA phantom using optimum CT acquisition parameters. Results: No statistical significant difference (p > 0.05) was found on CT numbers under the variation of different acquisition parameters for the same temperature setting. On the other hand, the RFA needle has induced metal artifacts on the CT images of up to 8 mm. The CT numbers decreased linearly when the phantom temperature increased from 37 to 80 °C. A linear regression analysis on the CT numbers and temperature suggested that the CT thermal sensitivity was -0.521 ± 0.061 HU/°C (R2 = 0.998). Conclusion: CT thermometry is feasible for temperature assessment during RFA with the current CT technology, which produced a high CT number reproducibility and stable measurement at different CT acquisition parameters. Despite being affected by metal artifacts, the CT-based thermometry could be further developed as a tissue temperature monitoring tool during CT-guided thermal ablation.
Identification of male-specific SNP markers and development of PCR-based genetic sex identification technique in crucifix crab (Charybdis feriatus) with implication of an XX/XY sex determination system

Fang S, Zhang Y, Shi X, Zheng H, Li S, Zhang Y, et al.

Genomics, 2020 01;112(1):404-411.
PMID: 30851358 DOI: 10.1016/j.ygeno.2019.03.003

In this study, we first identified male-specific SNP markers using restriction site-associated DNA sequencing, and further developed a PCR-based sex identification technique for Charybdis feriatus. A total of 296.96 million clean reads were obtained, with 114.95 and 182.01 million from females and males. After assembly and alignment, 10 SNP markers were identified being heterozygous in males but homozygous in females. Five markers were further confirmed to be male-specific in a large number of individuals. Moreover, two male-specific sense primers and a common antisense primer were designed, using which, a PCR-based genetic sex identification method was successfully developed and used to identify the sex of 103 individuals, with a result of 49 females and 54 males. The presence of male-specific SNP markers suggests an XX/XY sex determination system for C. feriatus. These findings should be helpful for better understanding sex determination mechanism, and drafting artificial breeding program in crustaceans.
Fulltext Psychometric properties and population norms of the positive mental health instrument in a representative multi-ethnic Asian population

Vaingankar JA, Subramaniam M, Tan LWL, Abdin E, Lim WY, Wee HL, et al.

BMC Med Res Methodol, 2018 03 15;18(1):29.
PMID: 29544448 DOI: 10.1186/s12874-018-0487-9

BACKGROUND: Measures of mental well-being and positive mental health (PMH) have been largely developed and used in Western populations, however, data on representative Asian communities are lacking. Using data from a population sample, this study sought to establish psychometric properties and norms of the PMH Instrument (PMH-I), a measure of positive mental health developed in Singapore.
METHODS: We conducted a nationally representative survey among 1925 adults aged 18-79 years of Chinese, Malay, Indian or other ethnicity. Participants reported socio-demographic characteristics and completed the PMH-I along with measures of health-related quality of life (HRQoL) and psychological distress. Construct validity of the PMH-I was assessed using confirmatory factor analysis and concurrent validity was tested through correlation with other psychological measures. Normative PMH values and differences in population subgroups were estimated.
RESULTS: The six-factor-higher-order structure of the PMH-I comprising six subscales of general coping, emotional support, spirituality, interpersonal skills, personal growth and autonomy and global affect was confirmed. Concurrent validity was shown through significant positive correlation of the total PMH score and its subscales with HRQoL and an inverse correlation with psychological distress. Weighted age, gender and ethnicity-specific norms were derived for the Singapore population. Total PMH was significantly higher in participants aged over 40 years as compared with 18-29 year olds and in non-Chinese ethnic groups as compared with Chinese. These differences were observed for all PMH-I subscales, with the exception of emotional support and interpersonal skills score differences by age. In contrast, gender, marital status, and education level were significantly associated with some of the subscales, but not with total PMH.
CONCLUSIONS: These results support the psychometric properties of the PMH-I in a multi-ethnic Asian population sample. The generalizable population-based norms support the application of the PMH-I for measuring mental health and assessing its determinants within the Singapore general population.
Acrylic-based genosensor utilizing metal salphen labeling approach for reflectometric dengue virus detection

Mazlan NF, Tan LL, Karim NHA, Heng LY, Jamaluddin ND, Yusof NYM, et al.

Talanta, 2019 Jun 01;198:358-370.
PMID: 30876573 DOI: 10.1016/j.talanta.2019.02.036

An optical genosensor based on Schiff base complex (Zn2+ salphen) DNA label and acrylic microspheres (AMs) as polymer support of the capturing DNA probe (cpDNA) was developed for dengue virus serotype 2 (DEN-2) detection via reflectance spectrophotometric method. The solid-state optical DNA biosensor showed high selectivity and specificity up to one-base mismatch in the target DNA sequence owing to the salphen chemical structure that is rich in localized electrons, and allowed π-π stacking interaction between stacked base pairs of double-stranded DNA (dsDNA). The reflectometric DNA microsensor demonstrated a broad linear detection range towards DEN-2 DNA from 1 × 10-15 M to 1 × 10-3 M with a low limit of detection (LOD) obtained at 1.21 × 10-16 M. The DNA biosensor gave reproducible optical response with a satisfactory relative standard deviation (RSD) at 3.1%, (n = 3), and the reflectance response was stable even after four regeneration cycles of the DNA biosensor. The optical genosensor was proven comparable with standard reverse transcription polymerase chain reaction (RT-PCR) in detecting DEN-2 genome acquired from clinical samples of serum, urine and saliva of dengue virus infected patients under informed consent. The developed reflectometric DNA biosensor is advantageous in offering an early DEN-2 diagnosis, when fever symptom started to manifest in patient.
Rapid assessment of total MCPD esters in palm-based cooking oil using ATR-FTIR application and chemometric analysis

Goh KM, Maulidiani M, Rudiyanto R, Wong YH, Ang MY, Yew WM, et al.

Talanta, 2019 Jun 01;198:215-223.
PMID: 30876552 DOI: 10.1016/j.talanta.2019.01.111

The technique of Fourier transform infrared spectroscopy is widely used to generate spectral data for use in the detection of food contaminants. Monochloropropanediol (MCPD) is a refining process-induced contaminant that is found in palm-based fats and oils. In this study, a chemometric approach was used to evaluate the relationship between the FTIR spectra and the total MCPD content of a palm-based cooking oil. A total of 156 samples were used to develop partial least squares regression (PLSR), artificial neural network (nnet), average artificial neural network (avNNET), random forest (RF) and cubist models. In addition, a consensus approach was used to generate fusion result consisted from all the model mentioned above. All the models were evaluated based on validation performed using training and testing datasets. In addition, the box plot of coefficient of determination (R2), root mean square error (RMSE), slopes and intercepts by 100 times randomization was also compared. Evaluation of performance based on the testing R2 and RMSE suggested that the cubist model predicted total MCPD content with the highest accuracy, followed by the RF, avNNET, nnet and PLSR models. The overfitting tendency was assessed based on differences in R2 and RMSE in the training and testing calibrations. The observations showed that the cubist and avNNET models possessed a certain degree of overfitting. However, the accuracy of these models in predicting the total MCPD content was high. Results of the consensus model showed that it slightly improved the accuracy of prediction as well as significantly reduced its uncertainty. The important variables derived from the cubist and RF models suggested that the wavenumbers corresponding to the MCPDs originated from the -CH=CH2 or CH=CH (990-900 cm-1) and C-Cl stretch (800-700 cm-1) regions of the FTIR spectrum data. In short, chemometrics in combination with FTIR analysis especially for the consensus model represent a potential and flexible technique for estimating the total MCPD content of refined vegetable oils.
Fulltext Clinical phenotypes of COPD and health-related quality of life: a cross-sectional study

Chai CS, Liam CK, Pang YK, Ng DL, Tan SB, Wong TS, et al.

Int J Chron Obstruct Pulmon Dis, 2019 03 01;14:565-573.
PMID: 30880946 DOI: 10.2147/COPD.S196109

Introduction: The Spanish COPD guideline (GesEPOC) classifies COPD into four clinical phenotypes based on the exacerbation frequency and dominant clinical manifestations. In this study, we compared the disease-specific health-related quality of life (HRQoL) of patients with different clinical phenotypes.
Methods: This was a cross-sectional study of patients with COPD attending the respiratory medicine clinic of University of Malaya Medical Centre from 1 June 2017 to 31 May 2018. Disease-specific HRQoL was assessed by using the COPD Assessment Test (CAT) and St George's Respiratory Questionnaire for COPD (SGRQ-c).
Results: Of 189 patients, 28.6% were of non-exacerbator phenotype (NON-AE), 18.5% were of exacerbator with emphysema phenotype (AE NON-CB), 39.7% were of exacerbator with chronic bronchitis phenotype (AE CB), and 13.2% had asthma-COPD overlap syndrome phenotype (ACOS). The total CAT and SGRQ-c scores were significantly different between the clinical phenotypes (P<0.001). Patients who were AE CB had significantly higher total CAT score than those with ACOS (P=0.033), AE NON-CB (P=0.001), and NON-AE (P<0.001). Concerning SGRQ-c, patients who were AE CB also had a significantly higher total score than those with AE NON-CB (P=0.001) and NON-AE (P<0.001). However, the total SGRQ-c score of AE CB patients was only marginally higher than those who had ACOS (P=0.187). There was a significant difference in the score of each CAT item (except CAT 7) and SGRQ-c components between clinical phenotypes, with AE CB patients recording the highest score in each of them.
Conclusion: Patients who were AE CB had significantly poorer HRQoL than other clinical phenotypes and recorded the worst score in each of the CAT items and SGRQ-c components. Therefore, AE CB patients may warrant a different treatment approach that focuses on the exacerbation and chronic bronchitis components.
Fulltext Parental concern of feeding difficulty predicts poor growth status in their child

Lee WS, Tee CW, Tan AG, Wong SY, Chew KS, Cheang HK, et al.

Pediatr Neonatol, 2019 12;60(6):676-683.
PMID: 31056340 DOI: 10.1016/j.pedneo.2019.04.004

BACKGROUND: Parents often express concerns about feeding difficulties in their child. We hypothesized that these parental concerns were associated with adverse growth status in early childhood. We aimed to determine the prevalence of such concerns and whether these concerns were associated with adverse growth status in early childhood.
METHODS: We performed a cross-sectional study among healthy children aged 12-36 months attending three well-baby clinics in three urban areas in Malaysia and Singapore between December 2016 and February 2017. Parents were interviewed for concerns about their child's feeding and presence of behavioral and organic red flags for feeding difficulties. We defined growth faltering as weight-for-age < 3rd centile and short stature as height-for-age < 3rd centile according to World Health Organization Growth Standards.
RESULTS: Of the 303 children studied (boys = 160, 52.8%; mean [± SD] chronological age at interview 21.3 [± 4.0] months), 13% (n = 38/292) had growth faltering and 19.5% (n = 50/256) had short stature. Overall, 36.3% (n = 110) of parents expressed concerns about their child's feeding behavior. Sixty-eight percent (n = 206) of parents reported presence of at least one behavioral and 18.5% (n = 56) had at least one organic red flag for feeding difficulties, respectively. 9.9% (n = 30) had both behavioral and organic red flags for feeding difficulties. Growth faltering was significantly associated with parental concern about feeding (odds ratio [OR] 3.049, p
Low Muscularity as Assessed by Abdominal Computed Tomography on Intensive Care Unit Admission Is Associated With Mortality in a Critically Ill Asian Population

Ng CC, Lee ZY, Chan WY, Jamaluddin MF, Tan LJ, Sitaram PN, et al.

JPEN J Parenter Enteral Nutr, 2020 03;44(3):425-433.
PMID: 31173666 DOI: 10.1002/jpen.1666

BACKGROUND: Low muscularity (LM) is associated with high mortality in the Caucasian critically ill population. Muscularity can be accurately measured by the skeletal muscle index (SMI; cm2 /m2 ) generated by computed tomography (CT). This study aimed to establish the overall and sex-specific cutoff values that predict hospital mortality in an Asian critically ill population.
METHODS: This single-center, retrospective, observational study included patients aged ≥18 years with an abdominal CT conducted within 72 hours of admission to the intensive care unit. SMI generated from CT images at the level of the mid-third lumbar vertebra were extracted from the medical records. Area under the receiver operating characteristic curves (AUC) was generated to determine the SMI cutoff values for hospital mortality. Association between LM (defined by SMI cutoff value) and hospital mortality was further evaluated by multivariable logistic regression.
RESULTS: In a sample of 228 patients, the overall SMI cutoff value (cm2 /m2 ) for hospital mortality was 42.0 (AUC: 0.637; sensitivity: 66.7%, specificity: 56.8%), whereas it was 46.5 in males and 35.3 in females. More males than females had LM (51.4% vs 37.5%), and >40% of overweight/obese patients had LM. Patients with LM were older and had a longer duration of mechanical ventilation and hospitalization. After adjusting for known confounders, LM independently predicted hospital mortality in the overall sample (adjusted odds ratio: 2.42; 95% CI 1.16-5.03; P = 0.003) and in both sexes.
CONCLUSION: This study established a set of SMI cutoff values that predict hospital mortality. LM is independently associated with hospital mortality.
Antiretroviral agents in pre-exposure prophylaxis: emerging and advanced trends in HIV prevention

Yap PK, Loo Xin GL, Tan YY, Chellian J, Gupta G, Liew YK, et al.

J Pharm Pharmacol, 2019 Sep;71(9):1339-1352.
PMID: 31144296 DOI: 10.1111/jphp.13107

OBJECTIVES: Antiretroviral agents (ARVs) have been the most promising line of therapy in the management of human immunodeficiency virus (HIV) infections. Some of these ARVs are used in the pre-exposure prophylaxis (PrEP) to suppress the transmission of HIV. Prophylaxis is primarily used in uninfected people, before exposure, to effectively prevent HIV infection. Several studies have shown that ART PrEP prevents HIV acquisition from sexual, blood and mother-to-child transmissions. However, there are also several challenges and limitations to PrEP. This review focuses on the current antiretroviral therapies used in PrEP.
KEY FINDINGS: Among ARVs, the most common drugs employed from the class of entry inhibitors are maraviroc (MVC), which is a CCR5 receptor antagonist. Other entry inhibitors like emtricitabine (FTC) and tenofovir (TFV) are also used. Rilpivirine (RPV) and dapivirine (DPV) are the most common drugs employed from the Non-nucleoside reverse transcriptase inhibitor (NNRTIs) class, whereas, tenofovir disoproxil fumarate (TDF) is primarily used in the Nucleoside Reverse Transcriptase Inhibitor (NRTIs) class. Cabotegravir (CAB) is an analog of dolutegravir, and it is an integrase inhibitor. Some of these drugs are also used in combination with other drugs from the same class.
SUMMARY: Some of the most common pre-exposure prophylactic strategies employed currently are the use of inhibitors, namely entry inhibitors, non-nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, integrase and protease inhibitors. In addition, we have also discussed on the adverse effects caused by ART in PrEP, pharmacoeconomics factors and the use of antiretroviral prophylaxis in serodiscordant couples.
Personalized administration of contrast medium with high delivery rate in low tube voltage coronary computed tomography angiography

Tan SK, Ng KH, Yeong CH, Raja Aman RRA, Mohamed Sani F, Abdul Aziz YF, et al.

Quant Imaging Med Surg, 2019 Apr;9(4):552-564.
PMID: 31143647 DOI: 10.21037/qims.2019.03.13

Background: High delivery rate is an important factor in optimizing contrast medium administration in coronary computed tomography angiography (CCTA). A personalized contrast volume calculation algorithm incorporating high iodine delivery rate (IDR) can reduce total iodine dose (TID) and produce optimal vessel contrast enhancement (VCE) in low tube voltage CCTA. In this study, we developed and validated an algorithm for calculating the volume of contrast medium delivered at a high rate for patients undergoing retrospectively ECG-gated CCTA with low tube voltage protocol.
Methods: The algorithm for an IDR of 2.22 gI·s-1 was developed based on the relationship between VCE and contrast volume in 141 patients; test bolus parameters and characteristics in 75 patients; and, tube voltage in a phantom study. The algorithm was retrospectively tested in 45 patients who underwent retrospectively ECG-gated CCTA with a 100 kVp protocol. Image quality, TID and radiation dose exposure were compared with those produced using the 120 kVp and routine contrast protocols.
Results: Age, sex, body surface area (BSA) and peak contrast enhancement (PCE) were significant predictors for VCE (P<0.05). A strong linear correlation was observed between VCE and contrast volume (r=0.97, P<0.05). The 100-to-120 kVp contrast enhancement conversion factor (Ec) was calculated at 0.81. Optimal VCE (250 to 450 HU) and diagnostic image quality were obtained with significant reductions in TID (32.1%) and radiation dose (38.5%) when using 100 kVp and personalized contrast volume calculation algorithm compared with 120 kVp and routine contrast protocols (P<0.05).
Conclusions: The proposed algorithm could significantly reduce TID and radiation exposure while maintaining optimal VCE and image quality in CCTA with 100 kVp protocol.
Fulltext Impact of a standardized protocol for the Management of Prolonged Neonatal Jaundice in a regional setting: an interventional quasi-experimental study

Tan HS, Balasubramaniam IS, Hss AS, Yeong ML, Chew CC, Singh RP, et al.

BMC Pediatr, 2019 05 29;19(1):174.
PMID: 31142302 DOI: 10.1186/s12887-019-1550-3

BACKGROUND: Prolonged neonatal jaundice (PNNJ) is often caused by breast milk jaundice, but it could also point to other serious conditions (biliary atresia, congenital hypothyroidism). When babies with PNNJ receive a routine set of laboratory investigations to detect serious but uncommon conditions, there is always a tendency to over-investigate a large number of well, breastfed babies. A local unpublished survey in Perak state of Malaysia revealed that the diagnostic criteria and initial management of PNNJ were not standardized. This study aims to evaluate and improve the current management of PNNJ in the administrative region of Perak.
METHODS: A 3-phase quasi-experimental community study was conducted from April 2012 to June 2013. Phase l was a cross-sectional study to review the current practice of PNNJ management. Phase ll was an interventional phase involving the implementation of a new protocol. Phase lll was a 6 months post-interventional audit. A registry of PNNJ was implemented to record the incidence rate. A self-reporting surveillance system was put in place to receive any reports of biliary atresia, urinary tract infection, or congenital hypothyroidism cases.
RESULTS: In Phase I, 12 hospitals responded, and 199 case notes were reviewed. In Phase II, a new protocol was developed and implemented in all government health facilities in Perak. In Phase III, the 6-month post-intervention audit showed that there were significant improvements when comparing mean scores of pre- and post-intervention: history taking scores (p
Fulltext Molecular identification of natural hybridization between Melastoma malabathricum and Melastoama beccarianum in Sarawak, Malaysia

Wu R, Zou P, Tan G, Hu Z, Wang Y, Ning Z, et al.

Ecol Evol, 2019 May;9(10):5766-5776.
PMID: 31160997 DOI: 10.1002/ece3.5160

Hybridization is very common in flowering plants and it plays a significant role in plant evolution and adaptation. Melastoma L. (Melastomataceae) comprises about 80-90 species in tropical Asia and Oceania, among which 41 species occur in Borneo. Natural hybridization is frequently reported in Melastoma in China, but so far there have been no confirmed cases of hybridization in Southeast Asia (including Borneo), where most species occur. Here, we identified a case of natural hybridization between Melastoma malabathricum L. and Melastoma beccarianum Cogn. in Sarawak, Malaysia, by using sequence data of three nuclear genes and one chloroplast intergenic spacer. Melastoma malabathricum is the most widespread species of this genus, occurring in almost the whole range of this genus, while M. beccarianum is a local species endemic to northern Borneo. Our results showed that natural hybridization and introgression occur between M. malabathricum and M. beccarianum, and the introgression was asymmetrical, mainly from M. malabathricum to M. beccarianum. As adaptive traits can be transferred by introgression, our study suggests that natural hybridization should be a significant mechanism for the evolution and adaptation of Melastoma in Southeast Asia. However, introgression from the common species M. malabathricum to the relatively rare species M. beccarianum may cause the decline of M. beccarianum, incurring conservation concern. With a large number of species of Melastoma and almost year-around flowering in Southeast Asia, more cases of natural hybridization are expected to be found and identified in near future.
Fulltext Antimicrobial Polymers: The Potential Replacement of Existing Antibiotics?

Kamaruzzaman NF, Tan LP, Hamdan RH, Choong SS, Wong WK, Gibson AJ, et al.

Int J Mol Sci, 2019 Jun 04;20(11).
PMID: 31167476 DOI: 10.3390/ijms20112747

Antimicrobial resistance is now considered a major global challenge; compromising medical advancements and our ability to treat infectious disease. Increased antimicrobial resistance has resulted in increased morbidity and mortality due to infectious diseases worldwide. The lack of discovery of novel compounds from natural products or new classes of antimicrobials, encouraged us to recycle discontinued antimicrobials that were previously removed from routine use due to their toxicity, e.g., colistin. Since the discovery of new classes of compounds is extremely expensive and has very little success, one strategy to overcome this issue could be the application of synthetic compounds that possess antimicrobial activities. Polymers with innate antimicrobial properties or that have the ability to be conjugated with other antimicrobial compounds create the possibility for replacement of antimicrobials either for the direct application as medicine or implanted on medical devices to control infection. Here, we provide the latest update on research related to antimicrobial polymers in the context of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) pathogens. We summarise polymer subgroups: compounds containing natural peptides, halogens, phosphor and sulfo derivatives and phenol and benzoic derivatives, organometalic polymers, metal nanoparticles incorporated into polymeric carriers, dendrimers and polymer-based guanidine. We intend to enhance understanding in the field and promote further work on the development of polymer based antimicrobial compounds.
Body Weight, Body Weight Perception, and Bullying Among Adolescents in Malaysia

Ganapathy SS, Tan L, Sooryanarayana R, Hashim MH, Saminathan TA, Ahmad FH, et al.

Asia Pac J Public Health, 2019 11;31(8_suppl):38S-47S.
PMID: 31617372 DOI: 10.1177/1010539519879339

Body weight is a factor, with body weight perception a mediator, toward being a victim of bullying. This study aimed to explore the association between body weight, body weight perception, and bullying among students 13 to 17 years of age in Malaysia. Data were collected using a self-administered questionnaire. A 2-stage stratified cluster sampling design was used, and 212 schools across Malaysia were selected for this survey. Body weight was measured and body weight perception was the student's reflection of their body weight. The prevalence of being bullied among adolescents in Malaysia was 16.2%. Being too thin or being obese increased the probability of being bullied. Students with a normal body mass index, but with a misperception of their body weight, also had increased odds of being bullied. Obesity prevention, together with instilling positive body weight perception, should be part of all programs directed toward tackling the problem of bullying.
Fulltext Oxidation and Polymerization of Triacylglycerols: In-Depth Investigations towards the Impact of Heating Profiles

Khor YP, Hew KS, Abas F, Lai OM, Cheong LZ, Nehdi IA, et al.

Foods, 2019 Oct 11;8(10).
PMID: 31614487 DOI: 10.3390/foods8100475

The stability of refined, bleached, and deodorized palm olein (RBDPO) was studied under controlled heating conditions. RBDPO was heated continuously for 24 h at 160, 170, and 180 °C, with oil sampled at four hour intervals. Thermo-oxidative alterations were measured through various parameters, such as monomeric oxidized triacylglycerols (oxTAG), total polar compounds (TPC), polymerized triacylglycerols (PTG), oxidative stability, and fatty acid composition. After 24 h of heating, the TPC and triacylglycerol oligomers showed a linear increase with heating time at all heating temperatures. At the end of the heating study, more epoxy acids were formed than keto and hydroxy acids. Moreover, caprylic acid, which was not present in fresh oil, was formed in significant amounts. The increase in oxTAG was strongly correlated with the increase in the p-anisidine value and total oxidation value. The decreases in diacylglycerol and free fatty acids were strongly correlated with an increase in PTG.
Fulltext When West Meets East: The Origins and Spread of Weedy Rice Between Continental and Island Southeast Asia

Neik TX, Chai JY, Tan SY, Sudo MPS, Cui Y, Jayaraj J, et al.

G3 (Bethesda), 2019 09 04;9(9):2941-2950.
PMID: 31292156 DOI: 10.1534/g3.119.400021

Weedy crop relatives are among the world's most problematic agricultural weeds, and their ability to rapidly evolve can be enhanced by gene flow from both domesticated crop varieties and wild crop progenitor species. In this study, we examined the role of modern commercial crop cultivars, traditional landraces, and wild relatives in the recent emergence and proliferation of weedy rice in East Malaysia on the island of Borneo. This region of Malaysia is separated from the Asian continent by the South China Sea, and weedy rice has become a major problem there more recently than on the Malaysian peninsular mainland. Using 24 polymorphic SSR loci and genotype data from the awn-length domestication gene An-1, we assessed the genetic diversity, population structure and potential origins of East Malaysian weeds; 564 weedy, cultivated and wild rice accessions were analyzed from samples collected in East Malaysia, Peninsular Malaysia and neighboring countries. While there is considerable evidence for contributions of Peninsular Malaysian weed ecotypes to East Malaysian populations, we find that local crop cultivars and/or landraces from neighboring countries are also likely contributors to the weedy rice infestations. These findings highlight the implications of genetic admixture from different cultivar source populations in the spread of weedy crop relatives and the urgent need for preventive measurements to maintain sustainable crop yields.
Fulltext Towards developing and validating Quality Physical Education in schools-The Asian physical education professionals' voice

Ho WKY, Ahmed MD, Khoo S, Tan CH, Dehkordi MR, Gallardo M, et al.

PLoS One, 2019;14(8):e0218158.
PMID: 31369586 DOI: 10.1371/journal.pone.0218158

Physical education professionals aim to develop quality programmes for physical education. This study aimed to develop and validate a scale using professionals' perceptions of Quality Physical Education QPE in Asia using twenty-four items regarding QPE quality issues. The items covered status and roles, development of educational elements and supportive features in physical education. A sample of N = 799 sport and physical education professionals from eleven Asian cities participated in this questionnaire survey. Twenty-four items relating to QPE were examined via exploratory factor analysis (EFA) using maximum likelihood extraction and direct oblimin rotation methods. Nevertheless, only 20 items were extracted following the EFA examination. Items 1, 9, 14 and 18 were excluded because of low factor loadings. The remaining items were clustered into four subscales: Development and Supportive Elements for Quality Physical Education in Schools (DSFQPE; α = .918), Core Values of Quality Physical Education (CVPE; α = .908), Curriculum Arrangement of Physical Activities (CAPA; α = .884) and Provision and Norms in Physical Education (PNPE; α = .865). The Cronbach's alpha coefficient (α = .875) indicated excellent internal consistency for the overall measure. Furthermore, the 4 retained factors from the EFA were assessed via robust confirmatory factor analysis (CFA). The 4-factor model demonstrated a good fit with the data (CMIN/DF = 3.450, CFI = .928, TLI = .916, PCFI = .801, RMSEA = .078). The study identified a 4-factor structure with internal consistency and acceptable interfactor correlations. The structure seemed to be applicable, including the twenty items identified as useful and necessary tools for the framework of analysis in the investigation of diverse settings for the study of quality physical education.
Fulltext Epithelial-to-mesenchymal transition (EMT) to sarcoma in recurrent lung adenosquamous carcinoma following adjuvant chemotherapy

Poh ME, Liam CK, Mun KS, Chai CS, Wong CK, Tan JL, et al.

Thorac Cancer, 2019 09;10(9):1841-1845.
PMID: 31350945 DOI: 10.1111/1759-7714.13156

Adjuvant chemotherapy has long been indicated to extend survival in completely resected stage IB to IIIA non-small cell lung cancer (NSCLC). However, there is accumulating evidence that chemotherapy or chemoradiotherapy can induce epithelial-to-mesenchymal transition (EMT) in disseminated or circulating NSCLC cells. Here, we describe the first case of EMT as the cause of recurrence and metastasis in a patient with resected stage IIB lung adenosquamous carcinoma after adjuvant chemotherapy. We review the literature and explore the possible mechanisms by which EMT occurs in disseminated tumor cells (DTC) or circulating tumor cells (CTC) in response to adjuvant chemotherapy (cisplatin) as a stressor. We also explore the possible therapeutic strategies to reverse EMT in patients with recurrence. In summary, although adjuvant cisplatin-based chemotherapy in resected NSCLC does extend survival, it may lead to the adverse phenomenon of EMT in disseminated tumor cells (DTC) or circulating tumor cells (CTC) causing recurrence and metastasis.

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