Recent research output from Malaysia (via PubMed). Updated automatically.
Kinetics, thermodynamics, equilibrium isotherms, and reusability studies of cationic dye adsorption by magnetic alginate/oxidized multiwalled carbon nanotubes composites.
Int J Biol Macromol. 2018 Nov 14;:
Authors: Boukhalfa N, Boutahala M, Djebri N, Idris A
Magnetic beads (AO-γ-Fe2O3) of alginate (A) impregnated with citrate coated maghemite nanoparticles (γ-Fe2O3) and oxidized multiwalled carbon nanotubes (OMWCNTs) were synthesized and used as adsorbent for the removal of methylene blue from water. The XRD analysis revealed that the diameter of γ-Fe2O3 is 10.24 nm. The mass saturation magnetization of AO-γ-Fe2O3 and γ-Fe2O3 were found to be 27.16 and 42.63 emu·g-1, respectively. The adsorption studies revealed that the data of MB isotherm were well fitted to the Freundlich model. The Langmuir isotherm model exhibited a maximum adsorption capacity of 905.5 mg·g-1. The adsorption was very dependent on initial concentration, adsorbent dose, and temperature. The beads exhibited high adsorption stability in large domain of pH (4-10). The thermodynamic parameters determined at 283, 293, 303, and 313 K revealed that the adsorption occurring was spontaneous and endothermic in nature. Adsorption kinetic data followed the intraparticle diffusion model. The AO-γ-Fe2O3 beads were used for six cycles without significant adsorptive performance loss. Therefore, the eco-friendly prepared AO-γ-Fe2O3 beads were considered as highly recyclable and efficient adsorbent for methylene blue as they can be easily separated from water after treatment.
PMID: 30447356 [PubMed - as supplied by publisher]
Sugar palm nanofibrillated cellulose (Arenga pinnata (Wurmb.) Merr): Effect of cycles on their yield, physic-chemical, morphological and thermal behavior.
Int J Biol Macromol. 2018 Nov 14;:
Authors: Ilyas RA, Sapuan SM, Ishak MR, Zainudin ES
Nanofibrillated cellulose (NFCs) were extracted from sugar palm fibres (SPS) in two separate stages; delignification and mercerization to remove lignin and hemicellulose, respectively. Subsequently, the obtained cellulose fibres were then mechanically extracted into nanofibres using high pressurized homogenization (HPH). The diameter distribution sizes of the isolated nanofibres were dependent on the cycle number of HPH treatment. TEM micro-images displayed the decreasing trend of NFCs diameter, from 21.37 to 5.5 nm when the number of cycle HPH was increased from 5 to 15 cycles, meanwhile TGA and XRD analysis showed that the degradation temperature and crystallinity of the NFCs were slightly increased from 347 to 347.3 °C and 75.38 to 81.19% respectively, when the number of cycles increased. Others analysis also were carried on such as FT-IR, FESEM, AFM, physical properties, zeta potential and yield analysis. The isolated NFCs may be potentially applied in various application, such as tissue engineering scaffolds, bio-nanocomposites, filtration media, bio-packaging and etc.
PMID: 30447353 [PubMed - as supplied by publisher]
Measuring Engagement in eHealth and mHealth Behavior Change Interventions: Viewpoint of Methodologies.
J Med Internet Res. 2018 Nov 16;20(11):e292
Authors: Short CE, DeSmet A, Woods C, Williams SL, Maher C, Middelweerd A, Müller AM, Wark PA, Vandelanotte C, Poppe L, Hingle MD, Crutzen R
Engagement in electronic health (eHealth) and mobile health (mHealth) behavior change interventions is thought to be important for intervention effectiveness, though what constitutes engagement and how it enhances efficacy has been somewhat unclear in the literature. Recently published detailed definitions and conceptual models of engagement have helped to build consensus around a definition of engagement and improve our understanding of how engagement may influence effectiveness. This work has helped to establish a clearer research agenda. However, to test the hypotheses generated by the conceptual modules, we need to know how to measure engagement in a valid and reliable way. The aim of this viewpoint is to provide an overview of engagement measurement options that can be employed in eHealth and mHealth behavior change intervention evaluations, discuss methodological considerations, and provide direction for future research. To identify measures, we used snowball sampling, starting from systematic reviews of engagement research as well as those utilized in studies known to the authors. A wide range of methods to measure engagement were identified, including qualitative measures, self-report questionnaires, ecological momentary assessments, system usage data, sensor data, social media data, and psychophysiological measures. Each measurement method is appraised and examples are provided to illustrate possible use in eHealth and mHealth behavior change research. Recommendations for future research are provided, based on the limitations of current methods and the heavy reliance on system usage data as the sole assessment of engagement. The validation and adoption of a wider range of engagement measurements and their thoughtful application to the study of engagement are encouraged.
PMID: 30446482 [PubMed - in process]
A comparison of aesthetic outcome between tissue adhesive and subcuticular suture in thyroidectomy wound closure in a multiracial country: A randomized controlled trial.
Asian J Surg. 2018 Nov 13;:
Authors: Teoh LY, Chong SS, Hoh SY, Teoh MS, Ng KL
OBJECTIVES: Monofilament sutures, both absorbable and non-absorbable, have been used for wound closure. Tissue adhesive has been used in closure of clean, low tension wounds. However, there have been very few published studies on the aesthetic outcomes in neck surgeries. The aim of this study is to compare the patients' and doctors' satisfaction scores in the aesthetic outcome between both methods of closure of thyroidectomy wounds using validated scoring systems.
METHODS: A double-blinded randomised controlled trial comparing the aesthetic outcome between tissue adhesive and conventional suture was conducted among patients undergoing thyroid and parathyroid surgeries. Ninety-six patients were randomised into two treatment groups. Patients' wounds were scored by an independent observer using the SBSES score at 6 weeks postoperatively and observer component of the POSAS score at 3 months.
RESULTS: Forty-nine patients were randomised to the tissue adhesive group while forty-seven patients received the conventional method. There was no statistical difference in the aesthetic outcome using the patient's scoring system between both arms, with a median score of 9 (p = 0.25, SD ± 6.5). The observer's satisfaction score using POSAS was also not statistically significant (median score of 14 (p = 0.77, SD ± 6.2)). No significance was found in the observer's median score using the SBSES scoring system either (score 3, p = 0.12, SD ± 1.3). However, there was significant reduction in the duration of closure using glue (4.42 mins vs 6.36 mins, p < 0.05).
CONCLUSION: Tissue adhesive offers a comparable cosmetic result to the absorbable suture in thyroidectomy wound closure.
PMID: 30446424 [PubMed - as supplied by publisher]
Production, structure and morphology of exopolysaccharides yielded by submerged fermentation of Antrodia cinnamomea.
Carbohydr Polym. 2019 Feb 01;205:271-278
Authors: Chen L, Wang Z, Zhang B, Ge M, Ng H, Niu Y, Liu L
Carbon and nitrogen sources in culture medium of Antrodia cinnamomea were optimized to eliminate the interference of exterior macromolecules on exopolysaccharide (EPS) yield by submerged fermentation. The results suggested that culture medium containing 50 g/L of glucose and 20 g/L of yeast extract as the optimal carbon and nitrogen sources could produce 1.03 g/L of exopolysaccharides. After purification, two heteropolysaccharides (AC-EPS1 and AC-EPS2) were obtained and characterized to provide the basic structure information. As the main component of the produced EPS, AC-EPS2 (accounting for 89.63%) was mainly composed of galactose (87.42%) with Mw (molecular weight) and R.M.S. (root-mean-square) radius of 1.18 × 105 g/mol and 25.3 nm, respectively. Furthermore, the spherical and flexible chain morphologies of EPS were observed in different solvents by TEM. The structural and morphological information of purified EPS were significant for further study on their structure-activity relationship and related applications.
PMID: 30446105 [PubMed - in process]
Characterization of a novel N-acylhomoserine lactonase, AidP, from Antarctic Planococcus sp.
Microb Cell Fact. 2018 Nov 17;17(1):179
Authors: See-Too WS, Convey P, Pearce DA, Chan KG
BACKGROUND: N-acylhomoserine lactones (AHLs) are well-studied signalling molecules produced by some Gram-negative Proteobacteria for bacterial cell-to-cell communication or quorum sensing. We have previously demonstrated the degradation of AHLs by an Antarctic bacterium, Planococcus versutus L10.15T, at low temperature through the production of an AHL lactonase. In this study, we cloned the AHL lactonase gene and characterized the purified novel enzyme.
RESULTS: Rapid resolution liquid chromatography analysis indicated that purified AidP possesses high AHL-degrading activity on unsubstituted, and 3-oxo substituted homoserine lactones. Liquid chromatography-mass spectrometry analysis confirmed that AidP functions as an AHL lactonase that hydrolyzes the ester bond of the homoserine lactone ring of AHLs. Multiple sequence alignment analysis and phylogenetic analysis suggested that the aidP gene encodes a novel AHL lactonase enzyme. The amino acid composition analysis of aidP and the homologous genes suggested that it might be a cold-adapted enzyme, however, the optimum temperature is 28 °C, even though the thermal stability is low (reduced drastically above 32 °C). Branch-site analysis of several aidP genes of Planococcus sp. branch on the phylogenetic trees also showed evidence of episodic positive selection of the gene in cold environments. Furthermore, we demonstrated the effects of covalent and ionic bonding, showing that Zn2+ is important for activity of AidP in vivo. The pectinolytic inhibition assay confirmed that this enzyme attenuated the pathogenicity of the plant pathogen Pectobacterium carotovorum in Chinese cabbage.
CONCLUSION: We demonstrated that AidP is effective in attenuating the pathogenicity of P. carotovorum, a plant pathogen that causes soft-rot disease. This anti-quorum sensing agent is an enzyme with low thermal stability that degrades the bacterial signalling molecules (AHLs) that are produced by many pathogens. Since the enzyme is most active below human body temperature (below 28 °C), and lose its activity drastically above 32 °C, the results of a pectinolytic inhibition assay using Chinese cabbage indicated the potential of this anti-quorum sensing agent to be safely applied in the field trials.
PMID: 30445965 [PubMed - in process]
Inter-sectoral approaches for the prevention and control of malaria among the mobile and migrant populations: a scoping review.
Malar J. 2018 Nov 16;17(1):430
Authors: Naing C, Whittaker MA, Tanner M
BACKGROUND: Malaria cases among mobile and migrant populations (MMPs) represent a large and important reservoir for transmission, if undetected or untreated. The objectives of this review were to identify which intersectoral actions have been taken and how they are applied to interventions targeted at the MMPs and also to assess the effect of interventions targeted to these special groups of population.
RESULTS: A total of 36 studies met the inclusion criteria for this review. Numerous stakeholders were identified as involved in the intersectoral actions to defeat malaria amongst MMPs. Almost all studies discussed the involvement of Ministry of Health/Public Health (MOH/MOPH). The most frequently assessed intervention among the studies that were included was the coverage and utilization of insecticide-treated nets as personal protective measures (40.5%), followed by the intervention of early diagnoses and treatment of malaria (33.3%), the surveillance and response activities (13.9%) and the behaviour change communication (8.3%). There is a dearth of information on how these stakeholders shared roles and responsibilities for implementation, and about the channels of communication between-and-within the partners and with the MOH/MOPH. Despite limited details in the studies, the intermediate outcomes showed some evidence that the intersectoral collaborations contributed to improvement in knowledge about malaria, initiation and promotion of bed nets utilization, increased access to diagnosis and treatment in a surveillance context and contributed towards a reduction in malaria transmission. Overall, a high proportion of the targeted MMPs was equipped with correct knowledge about malaria transmission (70%, 95% CI 57-83%). Interventions targeting the use of bed nets utilization were two times more likely to reduce malaria incidence amongst the targeted MMPs (summary OR 2.01, 95% CI 1.43-2.6) than the non-users. The various intersectoral actions were often more vertically organized and not fully integrated in a systemic way within a given country or sub-national administrative setting.
CONCLUSION: Findings suggest that interventions supported by the multiple stakeholders had a significant impact on the reduction of malaria transmission amongst the targeted MMPs. Well-designed studies from different countries are recommended to robustly assess the role of intersectoral interventions targeted to MMPs and their impact on the reduction of transmission.
PMID: 30445959 [PubMed - in process]
Quantifying the genetic parameters of feed efficiency in juvenile Nile tilapia Oreochromis niloticus.
BMC Genet. 2018 Nov 16;19(1):105
Authors: de Verdal H, Vandeputte M, Mekkawy W, Chatain B, Benzie JAH
BACKGROUND: Improving feed efficiency in fish is crucial at the economic, social and environmental levels with respect to developing a more sustainable aquaculture. The important contribution of genetic improvement to achieve this goal has been hampered by the lack of accurate basic information on the genetic parameters of feed efficiency in fish. We used video assessment of feed intake on individual fish reared in groups to estimate the genetic parameters of six growth traits, feed intake, feed conversion ratio (FCR) and residual feed intake in 40 pedigreed families of the GIFT strain of Nile tilapia, Oreochromis niloticus. Feed intake and growth were measured on juvenile fish (22.4 g mean body weight) during 13 consecutive meals, representing 7 days of measurements. We used these data to estimate the FCR response to different selection criteria to assess the potential of genetics as a means of increasing FCR in tilapia.
RESULTS: Our results demonstrate genetic control for FCR in tilapia, with a heritability estimate of 0.32 ± 0.11. Response to selection estimates showed FCR could be efficiently improved by selective breeding. Due to low genetic correlations, selection for growth traits would not improve FCR. However, weight loss at fasting has a high genetic correlation with FCR (0.80 ± 0.25) and a moderate heritability (0.23), and could be an easy to measure and efficient criterion to improve FCR by selective breeding in tilapia.
CONCLUSION: At this age, FCR is genetically determined in Nile tilapia. A selective breeding program could be possible and could help enabling the development of a more sustainable aquaculture production.
PMID: 30445908 [PubMed - in process]
Methylation and Acetylation Enhanced the Antidiabetic Activity of Some Selected Flavonoids: In Vitro, Molecular Modelling and Structure Activity Relationship-Based Study.
Biomolecules. 2018 Nov 15;8(4):
Authors: Ahmed QU, Sarian MN, Mat So'ad SZ, Latip J, Arief Ichwan SJ, Hussein NN, Taher M, Alhassan AM, Hamidon H, Fakurazi S
Flavonoids have been reported to exert antihyperglycemic effects and have potential to enhance the current therapy options against type 2 diabetes mellitus. However, the structure activity relationships (SAR) studies of flavonoids against this disease have not been thoroughly comprehended. Hence, in the present study, 14 structurally related flavonoids viz. wogonin, techtochrysin, norwogonin, isoscutellarein, hypolaetin, kaempferol, quercetin, methyl ether of wogonin, acetate of wogonin, acetate of norwogonin, 8-hydroxy-7-methoxyflavone, chrysin, (+)-catechin and (-)-epicatechin were taken into account for in vitro antidiabetic evaluation. Cell viability of RIN-5F pancreatic cells and 3T3-L1 pre-adipocyte cells was initially tested, then an insulin secretion assay of RIN-5F as well as adipogenesis and glucose uptake measurements of adipocyte were investigated. Subsequently, protein expressions study through adipokines measurement (leptin, adiponectin, TNF-α, RBP-4) via enzyme-linked immunosorbent assay (ELISA) kit, Western blotting analysis against GLUT4 and C/EBP-α as well as molecular docking against GLUT1 were analyzed. The results from cell culture antidiabetic assays (insulin secretion, adipogenesis, and glucose uptake), protein expressions and molecular docking pointed that the methoxy group at position C-8 is responsible for antidiabetic property of selected flavonoids via glucose uptake mechanism indicated by up regulation of GLUT4 and C/EBP-α expressions. The mechanism could be enhanced by the addition of an acetate group at C-5 and C-7 of the flavone skeleton.
PMID: 30445784 [PubMed - in process]
Information-Centric Network-Based Vehicular Communications: Overview and Research Opportunities.
Sensors (Basel). 2018 Nov 15;18(11):
Authors: Din IU, Kim BS, Hassan S, Guizani M, Atiquzzaman M, Rodrigues JJPC
Information Centric Network (ICN) is expected to be the favorable deployable future Internet paradigm. ICN intends to replace the current IP-based model with the name-based content-centric model, as it aims at providing better security, scalability, and content distribution. However, it is a challenging task to conceive how ICN can be linked with the other most emerging paradigm, i.e., Vehicular Ad hoc Network (VANET). In this article, we present an overview of the ICN-based VANET approach in line with its contributions and research challenges.In addition, the connectivity issues of vehicular ICN model is presented with some other emerging paradigms, such as Software Defined Network (SDN), Cloud, and Edge computing. Moreover, some ICN-based VANET research opportunities, in terms of security, mobility, routing, naming, caching, and fifth generation (5G) communications, are also covered at the end of the paper.
PMID: 30445723 [PubMed - in process]
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