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The properties of red seaweed (Kappaphycus alvarezii) and its effect on mammary carcinogenesis

Chang VS, Okechukwu PN, Teo SS

Biomed Pharmacother, 2017 Mar;87:296-301.
PMID: 28063411 DOI: 10.1016/j.biopha.2016.12.092

The edible red seaweed (Kappaphycus alvarezii) is one of the algae species which was found to be rich in nutrients and nutraceutical. Hence, K. alvarezii may have the ability to suppress cancer through its antiproliferative properties. The aim of this study was to investigate the potential compounds of K. alvarezii, cytotoxicity properties of K. alvarezii extract on breast cancer cell line (MCF-7), investigated toxicity effect of high dosage K. alvarezii extract in rats and determined the effect of K. alvarezii on 7, 12-dimethylbenz[a]anthracene (DMBA) mammary carcinogenesis in rats. The method of LCMS/MS and MTT assay were used. For animal study, sub-chronic toxicity method was used, the rats were supplemented with 2000mg/kg body weight daily of K. alvarezii crude extracts by oral gavage. For the anticancer effect of K. alvarezii crude extracts, this study consisted of three groups of the experimental, untreated and normal group of rats. The experimental and untreated groups of rats were induced with mammary tumour with DMBA. The experimental group of rats was given with K. alvarezii crude extracts orally. The results were being used to compare with the untreated group of rats and normal group of rats. All the rats were fed with standard diet and water ad libitum. Mortality, behavior changes and tumour sizes were observed specifically. The differences between the three groups of rats were evaluated by using the ANOVA test. By using LCMS/MS method, six unknown compounds were analysed. K. alvarezii crude extract reduced the cell viability of MCF-7 from 84.91% to 0.81% and the IC50 value is 4.1±0.69mg/mL. For sub-chronic and heavy metal toxicity studies, no significant difference was found in haematological and biochemical values of the control group and experimental group. The growth rate of tumours in the untreated group of rats was found significantly higher than the experimental group of rats. Besides that, the white blood cells level in untreated group was found significantly higher than the experimental group and the normal group. In conclusion, K. alvarezii extract might able to slow down the growth rate of the tumour cells, therefore, identification of an active compound of inhibition growth rate of the tumour cells can be positively carried out in the future.
de novo transcriptome assembly for discovering gene expressed in Holothuria leucospilota with exposed to copper

Leong RZL, Lim LH, Chew YL, Teo SS

Anim Biotechnol, 2023 Dec;34(9):4474-4487.
PMID: 36576030 DOI: 10.1080/10495398.2022.2158094

Sea cucumber is a bioremediator as it can composite organic matter and excrete inorganic matter. Sea cucumber has the potential to serve as a bioindicator in marine habitat as they provide an integrated insight into the status of their environment over long periods. Sea cucumbers are sensitive to the organic concentration in the marine environment and can effectively provide an early warning system for any organic contamination that can negatively impact the ecosystem. The availability of a reference transcriptome for sea cucumber would constitute an essential tool for identifying genes involved in crucial steps of the defence pathway. De novo assembly of RNA-seq data enables researchers to study the transcriptomes without needing a genome sequence. In this study, sea cucumbers fed with Kappaphycus alvarezii powder were treated with 0.20 mg/L copper concentration comprehensive transcriptome data containing 75,149 Unigenes, with a total length of 20,460,032 bp. A total of 8820 genes were predicted from the unigenes, annotated, and functionally categorized into 25 functional groups with approximately 20% cluster in signal transduction mechanism. The reference transcriptome presented and validated in this study is meaningful for identifying a wide range of gene(s) related to the bioindication of sea cucumber in a high copper environment.
Molecular cloning, homology modeling and site-directed mutagenesis of vanadium-dependent bromoperoxidase (GcVBPO1) from Gracilaria changii (Rhodophyta)

Baharum H, Chu WC, Teo SS, Ng KY, Rahim RA, Ho CL

Phytochemistry, 2013 Aug;92:49-59.
PMID: 23684235 DOI: 10.1016/j.phytochem.2013.04.014

Vanadium-dependent haloperoxidases belong to a class of vanadium enzymes that may have potential industrial and pharmaceutical applications due to their high stability. In this study, the 5'-flanking genomic sequence and complete reading frame encoding vanadium-dependent bromoperoxidase (GcVBPO1) was cloned from the red seaweed, Fracilaria changii, and the recombinant protein was biochemically characterized. The deduced amino acid sequence of GcVBPO1 is 1818 nucleotides in length, sharing 49% identity with the vanadium-dependent bromoperoxidases from Corralina officinalis and Cor. pilulifera, respectively. The amino acid residues associated with the binding site of vanadate cofactor were found to be conserved. The Km value of recombinant GcVBPO1 for Br(-) was 4.69 mM, while its Vmax was 10.61 μkat mg(-1) at pH 7. Substitution of Arg(379) with His(379) in the recombinant protein caused a lower affinity for Br(-), while substitution of Arg(379) with Phe(379) not only increased its affinity for Br(-) but also enabled the mutant enzyme to oxidize Cl(-). The mutant Arg(379)Phe was also found to have a lower affinity for I(-), as compared to the wild-type GcVBPO1 and mutant Arg(379)His. In addition, the Arg(379)Phe mutant has a slightly higher affinity for H2O2 compared to the wild-type GcVBPO1. Multiple cis-acting regulatory elements associated with light response, hormone signaling, and meristem expression were detected at the 5'-flanking genomic sequence of GcVBPO1. The transcript abundance of GcVBPO1 was relatively higher in seaweed samples treated with 50 parts per thousand (ppt) artificial seawater (ASW) compared to those treated in 10 and 30 ppt ASW, in support of its role in the abiotic stress response of seaweed.
MOLECULAR CLONING AND BIOCHEMICAL CHARACTERIZATION OF GALACTOSE-1-PHOSPHATE URIDYLYLTRANSFERASE FROM GRACILARIA CHANGII (RHODOPHYTA)(1)

Siow RS, Teo SS, Ho WY, Shukor MY, Phang SM, Ho CL

J Phycol, 2012 Feb;48(1):155-62.
PMID: 27009660 DOI: 10.1111/j.1529-8817.2011.01105.x

Galactose-1-phosphate uridylyltransferase (GALT) catalyzes the reversible conversion of glucose-1-phosphate and UDP-galactose to galactose-1-phosphate and UDP-glucose. This enzyme is also responsible for one of the biochemical steps that produce the precursors of agar and agarose. In this study, we report the molecular cloning and sequence analyses of a cDNA encoding GALT, from Gracilaria changii (B. M. Xia et I. A. Abbott) I. A. Abbott, J. Zhang et B. M. Xia, which constitutes a genus of seaweeds that supply more than 60% of the world's agar and agarose. We have subcloned this cDNA into a bacterial expression cloning vector and characterized the enzyme activities of its recombinant proteins in vitro. The GcGALT gene was shown to be up-regulated by salinity stresses. The abundance of transcripts encoding GcGALT was the highest in G. changii, followed by Gracilaria edulis and Gracilaria salicornia in a descending order, corresponding to their respective agar contents. Our findings indicated that GALT could be one of the components that determines the agar yield in Gracilaria species.
TRANSCRIPTOMIC ANALYSIS OF GRACILARIA CHANGII (RHODOPHYTA) IN RESPONSE TO HYPER- AND HYPOOSMOTIC STRESSES(1)

Teo SS, Ho CL, Teoh S, Rahim RA, Phang SM

J Phycol, 2009 Oct;45(5):1093-9.
PMID: 27032354 DOI: 10.1111/j.1529-8817.2009.00724.x

Osmotic stress is one of the most significant natural abiotic stresses that occur in the intertidal zones. Seaweeds may physiologically acclimate to changing osmolarity by altering their transcriptome. Here, we investigated the transcriptomic changes of Gracilaria changii (B. M. Xia et I. A. Abbott) I. A. Abbott, J. Zhang et B. M. Xia in response to hyper- and hypoosmotic stresses using a cDNA microarray approach. Microarray analysis revealed that 199 and 200 genes from ∼3,300 genes examined were up- and down-regulated by >2-fold in seaweed samples treated at 50 parts per thousand (ppt) artificial seawater (ASW) compared with those at 30 ppt ASW, respectively. The number of genes that were up- and down-regulated by >2-fold in seaweed samples treated at 10 ppt ASW compared with those at 30 ppt ASW were 154 and 187, respectively. A majority of these genes were only differentially expressed under hyper- or hypoosmotic conditions, whereas 67 transcripts were affected by both stresses. The findings of this study have shed light on the expression profiles of many transcripts during the acclimation of G. changii to hyperosmotic and hypoosmotic conditions. This information may assist in the prioritization of genes to be examined in future studies.
Profiling the transcriptome of Gracilaria changii (Rhodophyta) in response to light deprivation

Ho CL, Teoh S, Teo SS, Rahim RA, Phang SM

Mar Biotechnol (NY), 2009 Jul-Aug;11(4):513-9.
PMID: 19043658 DOI: 10.1007/s10126-008-9166-x

Light regulates photosynthesis, growth and reproduction, yield and properties of phycocolloids, and starch contents in seaweeds. Despite its importance as an environmental cue that regulates many developmental, physiological, and biochemical processes, the network of genes involved during light deprivation are obscure. In this study, we profiled the transcriptome of Gracilaria changii at two different irradiance levels using a cDNA microarray containing more than 3,000 cDNA probes. Microarray analysis revealed that 93 and 105 genes were up- and down-regulated more than 3-fold under light deprivation, respectively. However, only 50% of the transcripts have significant matches to the nonredundant peptide sequences in the database. The transcripts that accumulated under light deprivation include vanadium chloroperoxidase, thioredoxin, ferredoxin component, and reduced nicotinamide adenine dinucleotide dehydrogenase. Among the genes that were down-regulated under light deprivation were genes encoding light harvesting protein, light harvesting complex I, phycobilisome 7.8 kDa linker polypeptide, low molecular weight early light-inducible protein, and vanadium bromoperoxidase. Our findings also provided important clues to the functions of many unknown sequences that could not be annotated using sequence comparison.
Perception of nudge interventions to mitigate medication errors risk in healthcare service delivery

Chew KS, Ooi SK, Abdul Rahim NF, Wong SS, Kandasamy V, Teo SS

BMC Health Serv Res, 2023 Nov 27;23(1):1310.
PMID: 38012617 DOI: 10.1186/s12913-023-10247-7

BACKGROUND: Conventional cognitive interventions to reduce medication errors have been found to be less effective as behavioural change does not always follow intention change. Nudge interventions, which subtly steer one's choices, have recently been introduced.
METHODS: Conducted from February to May 2023, this study aimed to determine the relationships between perceived effectiveness and perceived ease of implementation of six nudge interventions to reduce medication errors, i.e., provider champion, provider's commitment, peer comparison, provider education, patient education and departmental feedback, and the moderating effects of seniority of job positions and clinical experience on nudge acceptability. Partial Least Square Structural Equation Modelling was used for data analysis.
RESULTS AND DISCUSSION: All six nudge strategies had significant positive relationships between perceived effectiveness and acceptability. In three out of six interventions, perceived ease of implementation was shown to have positive relationships with perceived acceptability. Only seniority of job position had a significant moderating effect on perceived ease of implementation in peer comparison intervention. Interventions that personally involve senior doctors appeared to have higher predictive accuracy than those that do not, indicating that high power-distance culture influence intervention acceptability.
CONCLUSION: For successful nudge implementations, both intrinsic properties of the interventions and the broader sociocultural context is necessary.
Fulltext The Role of Personality and Social Support in Health-Related Quality of Life in Chronic Kidney Disease Patients

Ibrahim N, Teo SS, Che Din N, Abdul Gafor AH, Ismail R

PLoS One, 2015;10(7):e0129015.
PMID: 26131714 DOI: 10.1371/journal.pone.0129015

BACKGROUND: Chronic kidney disease (CKD) is commonly associated with various negative health outcomes. The aim of this study was to examine the influence of personality and social support on health-related quality of life in patients with chronic kidney disease. Health-related quality of life (HRQoL) is the quality of life studied in relation to health, and it provides important information of patients' coping with their health issues.
METHOD: Participants comprised of 200 patients experiencing various stages of chronic kidney disease. All participants completed the Short-Form 36 (SF-36), Big Five Inventory (BFI) and the Medical Outcomes Study (MOS) Social Support questionnaires.
RESULTS: Participants consisted of 108 males (54.0%) and 92 females (46.0%) with the mean age of 59.3 years (SD 14.5). Results showed that higher levels of extraversion and lower perceived affectionate social support were associated with higher physical HRQoL, whereas higher levels of neuroticism were associated with poorer mental HRQoL.
CONCLUSION: The current study found that certain personality traits, namely extraversion and neuroticism, were found to be associated with HRQoL. In addition, affectionate social support was also associated with higher HRQoL. Therefore, special attention should be paid to the personality of CKD patients, as well as the type of social support that they have, in planning interventions to improve their health outcomes.
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.
The details are in the genome-wide SNPs: Fine scale evolution of the Malaysian weedy rice

Sudo MPS, Yesudasan R, Neik TX, Masilamany D, Jayaraj J, Teo SS, et al.

Plant Sci, 2021 Sep;310:110985.
PMID: 34315600 DOI: 10.1016/j.plantsci.2021.110985

Weedy rice (Oryza spp.) is a major nuisance to rice farmers from all over the world. Although the emergence of weedy rice in East Malaysia on the island of Borneo is very recent, the threat to rice yield has reached an alarming stage. Using 47,027 genotyping-by-sequencing (GBS)-derived SNPs and candidate gene analysis of the plant architecture domestication gene TAC1, we assessed the genetic variations and evolutionary origin of weedy rice in East Malaysia. Our findings revealed two major evolutionary paths for genetically distinct weedy rice types. Whilst the cultivar-like weedy rice are very likely to be the weedy descendant of local coexisting cultivars, the wild-like weedy rice appeared to have arisen through two possible routes: (i) accidental introduction from Peninsular Malaysia weedy rice populations, and (ii) weedy descendants of coexisting cultivars. The outcome of our genetic analyses supports the notion that Sabah cultivars and Peninsular Malaysia weedy rice are the potential progenitors of Sabah weedy rice. Similar TAC1 haplotypes were shared between Malaysian cultivated and weedy rice populations, which further supported the findings of our GBS-SNP analyses. These different strains of weedy rice have convergently evolved shared traits, such as seeds shattering and open tillers. A comparison with our previous simple-sequence repeat-based population genetic analyses highlights the strength of genome-wide SNPs, including detection of admixtures and low-level introgression events. These findings could inform better strategic management for controlling the spread of weedy rice in the region.
Identification of microorganisms from fermented biowaste and the potential for wastewater treatment

Zhi Ling RL, Kong LK, Lim LH, Teo SS, Ng HS, Lan JC, et al.

Environ Res, 2023 Feb 01;218:115013.
PMID: 36495970 DOI: 10.1016/j.envres.2022.115013

Food loss or waste is a far-reaching problem and has indeed become a worrying issue that is growing at an alarming rate. Fruits and vegetables are lost or wasted at the highest rate among the composition of food waste. Furthermore, the world is progressing toward sustainable development; hence, an efficient approach to valorise fruit and vegetable waste (FVW) is necessary. A simple phenotypic characterisation of microbiota isolated from the fermented FVW was conducted, and its effectiveness toward wastewater treatment was investigated. Presumptive identification suggested that yeast is dominant in this study, accounting for 85% of total isolates. At the genus level, the enriched medium's microbial community consists of Saccharomyces, Bacillus and Candida. Ammonium in the wastewater can enhance certain bacteria to grow, such as lactic acid bacteria, resulting in decreased NH4+ concentration at the end of the treatment to 0.5 mg/L. In addition, the fermented biowaste could reduce PO43- by 90% after the duration of treatment. Overall, FVW is a valuable microbial resource, and the microbial population enables a reduction in organic matter such as NH4+ and PO43-. This study helps explore the function and improve the effectiveness of utilising biowaste by understanding the microorganisms responsible for producing eco-enzyme.
Perovskite oxide for emerging photo(electro)catalysis in energy and environment

Li M, Han N, Zhang X, Wang S, Jiang M, Bokhari A, et al.

Environ Res, 2022 Apr 01;205:112544.
PMID: 34902376 DOI: 10.1016/j.envres.2021.112544

Using solar energy to catalyse photo-driven processes to address the energy crisis and environmental pollution plays a role in the path to a sustainable society. Many oxide-based materials, especially perovskite oxides, have been widely investigated as catalysts for photocatalysis in energy and environment because of the low-cost and earth-abundant and good performance. At this stage, there is a need to present a scientific-based evaluation of the technologies developed so far and identify the most sustainable technologies and the existing limitations and opportunities for their commercialisation. This work comprehensively investigated the outcomes using various scientometric indices on perovskite oxide-based photo(electro)catalysts for water splitting, nitrogen fixation, carbon dioxide conversion, organic pollutant degradation, current trends and advances in the field. According to the results achieved, efforts in both energy and environment based on perovskite oxides have been initiated in the 1990s and accelerated since the 2010s. China and the United States were identified as the most contributing countries. Based on the results achieved in this study, the main milestones and current trends in the development of this field have been identified. The aim of this research is to provide useful guidelines for the further investigation of perovskite oxide-based catalysts for photoelectrocatalysis and photocatalysis both in energy and environment on the applications such as water splitting, nitrogen fixation, carbon dioxide conversion, and wastewater treatment.

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