Scopus 2016-2017
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Publication Metadata only Scale up of a Plasmodium falciparum elimination program and surveillance system in Kayin State, Myanmar(2017-01-01) Daniel M. Parker; Jordi Landier; Aung Myint Thu; Khin Maung Lwin; Gilles Delmas; François H. Nosten; Mahidol University; Nuffield Department of Clinical Medicine© 2017 Parker DM et al. Background: Myanmar has one of the largest malaria burdens in Southeast Asia. Along the border with Thailand, Plasmodium falciparum parasites are increasingly showing reduced sensitivity to artemisinin combination therapies. Given that there are no current alternative treatment therapies, one proposed solution to the threat of untreatable P. falciparum malaria is to eliminate the parasite from the region. Several small-scale elimination projects have been piloted along the Myanmar-Thailand border. Following their success, this operational research aimed to scale up the elimination to a broad area of Eastern Kayin State, Myanmar. Methods: The project relied on geographic reconnaissance and a geographic information system, community engagement, generalized access to community-based early diagnosis and treatment, near real-time epidemiological surveillance, cross sectional malaria prevalence surveys and targeted mass drug administration in villages with high prevalence of P. falciparum malaria. Molecular markers of drug resistance were also monitored in individuals with symptomatic and asymptomatic infections. Discussion: This project illustrates the establishment of an elimination project and operational research in a remote, rural area encompassing several armed groups, multiple political organizations and a near-absent health care infrastructure. The establishment of the project relied on a strong rapport with the target community, on-the-ground knowledge (through geographic surveys and community engagement), rapid decision making and an approach that was flexible enough to quickly adapt to a complex landscape. The elimination project is ongoing, now over three years in operation, and assessment of the impact of this operational research will follow. This project has relevance not only for other malaria elimination projects but also for operational research aimed at eliminating other diseases.Publication Metadata only Economic growth and selection of municipal waste treatment options in Bangkok(2017-01-01) Shigefumi Okumura; Tomohiro Tasaki; Yuichi Moriguchi; Wassana Jangprajak; University of Tokyo; National Institute for Environmental Studies of Japan; Faculty of Environment and Resource Studies, Mahidol University© 2016, Springer Japan. A reasonable selection of waste treatment options is indispensable to address challenges in waste management. Introduction of incineration plants for municipal waste in Bangkok had been considered in the past, but each time it was dismissed. In 2013, however, the Bangkok Metropolitan Administration (BMA) decided to introduce an incinerator facility with electricity generation. This study examined how changes in socio-economic factors resulting from economic growth affected the BMA’s decision. First, we conducted interviews of key relevant stakeholders (policymakers and other experts) to determine what kinds of changes in socio-economic factors affected their decision. Then, for interpretation and confirmation of the results from interview, we quantitatively estimated changes in environmental factors (e.g., greenhouse gas emissions), financial factors (e.g., construction and operating costs), and social factors (e.g., employment) in 1990, 2000, and 2012. Based on the result of interview and quantitative analysis, we illustrated the complicated structure of the mechanism of how economic growth affected the selection of waste treatment options in Bangkok, particularly those that led to the selection of the incineration. In addition to local conditions, global economic also affected the waste treatment policy in Bangkok even though waste management is usually thought of as a local issue.Publication Metadata only Fabrication study of hydrophobic polyurethane sponge for oil absorption application(2017-01-01) Peeranut Prakulpawong; Jinjutha Wiriyanantawong; Janista Pornpoonsawat; Supan Yodyingyong; Darapond Triampo; Mahidol University© 2017 Trans Tech Publications, Switzerland. In this research, the researchers study the fabrication of oil absorption, hydrophobic polyurethane (PU) sponge for application in an oil-spill cleanup model. Virgin PU is initially hydrophilic. PU is made hydrophobic by incorporating hydrophobic silica aerogel (SA) into PU 3D porous structure by stirring method and UV-treatment method. UV-irradiation promotes the attachment of SA onto the PU surface. Varying UV irradiation time and concentration of SA is done to attain an optimal attachment of SA on PU. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and contact angle measurements (CA) are used to determine the adhesion of SA on PU. The loadings of SA with and without UV-treatment are compared. Results show that SA-PU with UV-treatment has more loading of SA than SA-PU without treatment. FT-IR spectra and SEM micrographs verify the results. Moreover, the SA-PU is tested for oil absorption to simulate oil-spill cleanup. The findings show fast (less than 3 seconds), recoverable oil-spills cleanup with simple method of preparation. In addition, SA-PU with UV treatment has higher absorption rate and absorption efficiency when compared to original PU and SA-PU without UV treatment.Publication Metadata only Development of LeHab robot for human lower limb movement rehabilitation(2017-12-19) Maheasak Rachakorakit; Warakorn Charoensuk; Mahidol University© 2017 IEEE. Rehabilitation is very important for patients who suffer from stroke or spinal cord injury. To restore musculature, it is necessary to prepare for the next step of therapeutics. The passive exercise is one of the method to maintain the musculature and prevent complication as deep vein thrombosis (DVT) as the patient cannot move leg until patient has been recovered. After that active exercise can be applied afterwards to maintain leg muscle and recover strength. In the past, the physical therapists are the person to use for treatment. The passive exercise and active exercise required a long time that makes physical therapists get fatigue. So Lehab robot was designed to assist therapist and improve quality of treatment. This robot was designed with four degree of freedom. Hip flexion-extension adduct-abduct, knee flexion-extension, ankle dorsiflexion-plantarflexion by applied PID controller for control each other joint of robot.Publication Metadata only Activation of dengue virus-specific T cells modulates vascular endothelial growth factor receptor 2 expression(2017-09-01) Jittraporn Rattanamahaphoom; Pornsawan Leaungwutiwong; Kriengsak Limkittikul; Nathamon Kosoltanapiwat; Anon Srikaitkhachorn; Mahidol University; University of Rhode Island© 2017, Allergy and Immunology Society of Thailand. All rights reserved. Background: The pathogenic mechanisms underlying the increased vascular permeability in dengue hemorrhagic fever (DHF) are not well understood. Enhanced cellular immune activation, especially activation of serotype-cross reactive T cells, has been implicated in plasma leakage in DHF. Changes in several biological markers and mediators including cytokines, chemokines, angiogenic factors and their receptors have been shown to correlate with disease severity. A decline in plasma levels of a soluble form of vascular endothelial growth factor receptor 2 (VEGFR2), a receptor of vascular endothelial growth factor (VEGF), has been associated with plasma leakage in dengue patients. Objective: We aimed to investigate the effect of dengue virus (DV)-specific CD8+ T cells on the expression of VEGFR2 on endothelial cells. Method: An in vitro model was developed in which dengue virus-specific CD8+ T cells generated from peripheral blood mononuclear cells (PBMCs) of DHF patients were co-cultured with antigen-presenting cells, human umbilical vein endothelial cells (HUVECs) and activated with DV non-structural protein 3 (NS3) peptides. The expression of VEGFR2 by endothelial cells was measured. Results: DV-specific CD8+ T cells were serotype cross-reactive. Activation of DV-specific CD8+ T cells resulted in down-regulation of soluble VEGFR2 production and an up-regulation of cell-associated VEGFR2. Conclusions: Our findings indicate that activation of DV-specific T cell is associated with modulation of VEGFR2 expression that may contribute to increased VEGF responsiveness and vascular permeabilityPublication Metadata only Inequity of healthcare utilization on mammography examination and Pap smear screening in Thailand: Analysis of a population-based household survey(2017-03-01) Sukanya Chongthawonsatid; Mahidol University© 2017 Sukanya Chongthawonsatid.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Healthcare in Thailand is not equally distributed, and not all people can equally access healthcare resources even if they are covered by health insurance. To examine factors associated with the utilization of mammography examination for breast cancer and Pap smear screening for cervical cancer, data from the national reproductive health survey conducted by the National Statistical Office of Thailand in 2009 was examined. The survey was carried out on 15,074,126 women aged 30±59 years. The results showed that the wealthier respondents had more mammograms than did the lower-income groups. The concentration index was 0.144. The data on Pap smears for cervical cancer also showed that the wealthier respondents were more likely to have had a Pap smear than their lower-income counterparts. The concentration index was 0.054. Determinants of mammography examination were education, followed by health welfare and wealth index, whereas the determinants of Pap smear screening were wealth index, followed by health welfare and education. The government should support greater education for women because education was associated with socioeconomic status and wealth. There should be an increase in the number of screening campaigns, mobile clinics, and low-cost mammograms and continued support for accessibility to mammograms, especially in rural areas and low-income communities.Publication Metadata only Preface(2017-11-01) Shabbir H. Gheewala; Thapat Silalertruksa; Pomthong Malakul; Trakarn Prapaspongsa; King Mongkut s University of Technology Thonburi; Chulalongkorn University; Mahidol UniversityPublication Metadata only Molecular investigation by whole exome sequencing revealed a high proportion of pathogenic variants among Thai victims of sudden unexpected death syndrome(2017-07-01) Bhoom Suktitipat; Sakda Sathirareuangchai; Ekkapong Roothumnong; Wanna Thongnoppakhun; Purin Wangkiratikant; Nutchavadee Vorasan; Rungroj Krittayaphong; Manop Pithukpakorn; Warangkna Boonyapisit; Mahidol University© 2017 Suktitipat et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Introduction: Sudden unexpected death syndrome (SUDS) is an important cause of death in young healthy adults with a high incident rate in Southeast Asia; however, there are no molecular autopsy reports about these victims. We performed a combination of both a detailed autopsy and a molecular autopsy by whole exome sequencing (WES) to investigate the cause of SUDS in Thai sudden death victims. Materials and methods: A detailed forensic autopsy was performed to identify the cause of death, followed by a molecular autopsy, in 42 sudden death victims who died between January 2015 and August 2015. The coding sequences of 98 SUDS-related genes were sequenced using WES. Potentially causative variants were filtered based on the variant functions annotated in the dbNSFP database. Variants with inconclusive clinical significance evidence in ClinVar were resolved with a variant prediction algorithm, metaSVM, and the frequency data of the variants found in public databases, such as the 1000 Genome Project, ESP6500 project, and the Exome Aggregation Consortium (ExAc) project. Results: Combining both autopsy and molecular autopsy enabled the potential identification of cause of death in 81% of the cases. Among the 25 victims with WES data, 72% (18/25) were found to have potentially causative SUDS mutations. The majority of the victims had at a mutation in the TTN gene (8/18 = 44%), and only one victim had an SCN5A mutation. Conclusions: WES can help to identify the genetic causes in victims of SUDS and may help to further guide investigations into their relatives to prevent additional SUDS victims.Publication Metadata only Activation of cryptic phthoxazolin A production in Streptomyces avermitilis by the disruption of autoregulator-receptor homologue AvaR3(2017-12-01) Dian Anggraini Suroto; Shigeru Kitani; Kiyoko T. Miyamoto; Yasuko Sakihama; Masayoshi Arai; Haruo Ikeda; Takuya Nihira; Osaka University; Hokkaido University; Kitasato University; Mahidol University© 2017 The Society for Biotechnology, Japan The genomes of actinomycetes encode many cryptic novel/useful bioactive compounds, but access to these cryptic secondary metabolites remains limited. Streptomyces avermitilis predominantly produces three polyketide antibiotics (avermectin, filipin, and oligomycin) but has the potential to produce more secondary metabolites based on the number of cryptic biosynthetic gene clusters. Here, we extensively investigated the metabolite profiles of a gene disruptant of AvaR3 (an autoregulator receptor homologue), which is involved in the pleiotropic regulation of antibiotic production and cell morphology. Unlike the wild-type strain, the avaR3 mutant accumulated compound 3 in the culture. The chemical structure of compound 3 was elucidated on the basis of various spectroscopic analyses, and was identified as phthoxazolin A, a cellulose synthesis inhibitor. Bioassays demonstrated that compound 3 exerts growth inhibitory activity against a broad range of plant pathogenic oomycetes. Moreover, unlike avermectin production, phthoxazolin A (3) production was negatively controlled by avenolide, a new type of autoregulator in streptomycetes, through the function of AvaR3. These results suggest that the genetic manipulation of autoregulator receptor homologues would be a valuable tool for the discovery of cryptic bioactive compounds.Publication Metadata only A Development of Supervised-Online Personal Learning Environment: Examining Factors Affecting Self-Directed Learning and Conceptual Understanding Progression(2017-11-15) Niwat Srisawasdi; Patcharin Panjaburee; Khon Kaen University; Mahidol University© 2017 IEEE. Personalized web-based learning environment have enhanced the value of instruction procedures in educational organizations. In doing so, a novel personalized web-based learning environment harmonizing with embedded pedagogy and formative assessment was developed in this study. The web-based learning systems that support students learning performance and attitudes, and factors that increase students acceptance of the systems have been widely study in recent years. However, the effect of factors on students self-directed learning and conceptual understanding progression is not explored yet. According to the developed web-based learning environment, this study choose pedagogy and formative assessment as important factors in promoting self-directed learning and increasing conceptual understanding. Our results suggest that scientific inquiry learning with relevance to daily life, with corresponding to individual characteristics, and with formative assessment affecting self-directed learning and conceptual understanding progression gained by a personalized web-based learning environment.Publication Metadata only Factors affecting the intention to buy electric vehicles: Empirical evidence from Thailand(2017-01-01) Trin Thananusak; Sirisuhk Rakthin; Thiti Tavewatanaphan; Prattana Punnakitikashem; Mahidol UniversityCopyright © 2017 Inderscience Enterprises Ltd. This study used partial least squares structural equation modelling (PLS-SEM) to test the relationships between the five factors (financial factors, infrastructure, performance, environmental concern, and price-premium) and intention to buy electric vehicles (EVs) in Thailand. Our findings suggest that the Thai car buyers pay attention to the performance factor of EVs (e.g., driving range, speed, safety) whilst not being concerned much with the infrastructure (e.g., charging facilities) and the financial factors (purchase price, operation and maintenance costs, resale price) of EVs. Moreover, the individuals’ environmental concerns affect the decision to own EVs and Thai customers are willing to pay for a price-premium for EVs. However, price-premium factor could negatively moderate the relationship between the environmental concern and intention to buy EVs. That is, if the price-premium of EVs becomes too high, people with a pro-environmental ethos may be less likely to adopt EVs.Publication Metadata only L929 cell cytotoxicity associated with experimental and commercial dental flosses(2017-11-29) P. Tua-Ngam; L. Supanitayanon; S. Dechkunakorn; N. Anuwongnukroh; T. Srikhirin; P. Roongrujimek; Mahidol University© 2017 Published under licence by IOP Publishing Ltd. This aim of the study was to investigate the cytotoxicity of two commercial and two experimental dental flosses. Two commercial, Oral B® Essential Floss (nylon-waxed) and Thai Silk Floss (silk-waxed), and two experimental, Floss X (nylon-waxed) and Floss Xu (nylon-unwaxed) dental flosses were used. The cytotoxic assay was performed by using cell cultures (L929) which were subjected to cell viability test with methyl-tetrazolium. Each floss specimen (0.4 g) was placed in 1 ml of Minimum Essential Medium at 37°C with 5% CO2at 100% humidity in an incubator for 24 hours. After incubation, the cell mitochondrial activity was evaluated for detecting viable cells using optical density as per the guidelines of ISO 10993-5:2009(E). Cytotoxic effects were evaluated by measuring percentage of cell viability at 3 points of time- 5 mins, 30 mins, and 1 hr. The results showed that two commercial dental flosses and Floss X had cell viability about 90% at the three time points; however, the experimental Floss Xu presented 80% cell viability at 5 min and <70% cell viability at 30 min and 1 hr. The results concluded that the commercial dental flosses and the experimental dental floss with wax tested in this study were acceptable for clinical use.Publication Metadata only Derangement of calcium metabolism in diabetes mellitus: negative outcome from the synergy between impaired bone turnover and intestinal calcium absorption(2017-01-01) Kannikar Wongdee; Nateetip Krishnamra; Narattaphol Charoenphandhu; Mahidol University; Burapha University© 2016, The Physiological Society of Japan and Springer Japan. Both types 1 and 2 diabetes mellitus (T1DM and T2DM) are associated with profound deterioration of calcium and bone metabolism, partly from impaired intestinal calcium absorption, leading to a reduction in calcium uptake into the body. T1DM is associated with low bone mineral density (BMD) and osteoporosis, whereas the skeletal changes in T2DM are variable, ranging from normal to increased and to decreased BMD. However, both types of DM eventually compromise bone quality through production of advanced glycation end products and misalignment of collagen fibrils (so-called matrix failure), thereby culminating in a reduction of bone strength. The underlying cellular mechanisms (cellular failure) are related to suppression of osteoblast-induced bone formation and bone calcium accretion, as well as to enhancement of osteoclast-induced bone resorption. Several other T2DM-related pathophysiological changes, e.g., osteoblast insulin resistance, impaired productions of osteogenic growth factors (particularly insulin-like growth factor 1 and bone morphogenetic proteins), overproduction of pro-inflammatory cytokines, hyperglycemia, and dyslipidemia, also aggravate diabetic osteopathy. In the kidney, DM and the resultant hyperglycemia lead to calciuresis and hypercalciuria in both humans and rodents. Furthermore, DM causes deranged functions of endocrine factors related to mineral metabolism, e.g., parathyroid hormone, 1,25-dihydroxyvitamin D3, and fibroblast growth factor-23. Despite the wealth of information regarding impaired bone remodeling in DM, the long-lasting effects of DM on calcium metabolism in young growing individuals, pregnant women, and neonates born to women with gestational DM have received scant attention, and their underlying mechanisms are almost unknown and worth exploring.Publication Metadata only Geographic Resource Allocation Based on Cost Effectiveness: An Application to Malaria Policy(2017-06-01) Tom L. Drake; Yoel Lubell; Shwe Sin Kyaw; Angela Devine; Myat Phone Kyaw; Nicholas P.J. Day; Frank M. Smithuis; Lisa J. White; Myanmar Oxford Clinical Research Unit; Nuffield Department of Clinical Medicine; Mahidol University; Ministry of Health© 2017, The Author(s). Healthcare services are often provided to a country as a whole, though in many cases the available resources can be more effectively targeted to specific geographically defined populations. In the case of malaria, risk is highly geographically heterogeneous, and many interventions, such as insecticide-treated bed nets and malaria community health workers, can be targeted to populations in a way that maximises impact for the resources available. This paper describes a framework for geographically targeted budget allocation based on the principles of cost-effectiveness analysis and applied to priority setting in malaria control and elimination. The approach can be used with any underlying model able to estimate intervention costs and effects given relevant local data. Efficient geographic targeting of core malaria interventions could significantly increase the impact of the resources available, accelerating progress towards elimination. These methods may also be applicable to priority setting in other disease areas.Publication Metadata only Potential Prebiotic Oligosaccharide Mixtures from Acidic Hydrolysis of Rice Bran and Cassava Pulp(2017-12-01) Chanida Hansawasdi; Peter Kurdi; Mahidol University; Thailand National Center for Genetic Engineering and Biotechnology© 2017, Springer Science+Business Media, LLC. Two agricultural wastes, rice bran and cassava pulp were subjected to acidic hydrolysis by 2 M sulfuric acid which resulted in hemicellulosic oligosaccharide mixtures. Monosaccharide component analysis of these mixtures revealed that the oligosaccharides of rice bran acid hydrolysate (RAHF) composed of glucose and arabinose while cassava pulp acid hydrolysate (CAHF) was found to be comprised of glucose, galactose and arabinose. Both RAHF and CAHF were able to fuel all of the tested three Lactobacillus, five Bifidobacterium and three Bacteroides strains indicating the prebiotic potential of these oligosaccharide mixtures. Moreover, Lb. gasseri grew significantly better on RAHF than on inulin, a benchmark prebiotic oligo- and polysaccharide mixture. When the digestibility of RAHF and CAHF were tested it was found that these oligosaccharide mixtures were only slightly hydrolyzed upon exposure to simulated human gastric (by less than 8%) and pancreatic juices (by less than 3%). Additionally, most sensory attributes of the above obtained oligosaccharide mixtures supplemented two model cereal drink formulations were generally not different from those of the control, while the overall acceptance was not affected significantly in one cereal drink formulation.Publication Metadata only Robust human re-identification using mean shape analysis of face images(2017-12-19) Sarattha Kanchanapreechakorn; Worapan Kusakunniran; Mahidol University© 2017 IEEE. Human re-identification is an important component in many application domains especially the automatic surveillance system. This paper proposes a robust method to re-identify persons using their face shapes based on the Active Shape Model (ASM) and the Procrustes Shape Analysis (PSA). The ASM-based technique is used to extract landmark points of each face image, as the feature. Then, the Procrustes Distance (PD) is used to measure the similarity between two ASMs of any two face images. In addition, the trained ASMs of each subject can be grouped into clusters, using the PD-based K-mean clustering. Then, the Procrustes Mean Shape (PMS) is computed for each cluster using all belonging ASMs. In stead of using ASM of individual face image, the PMS is used as the representative face model. This process is performed to increase the robustness and reduce the number of models representing each subject. The proposed method is evaluated on the well-known face datasets and the real-world scenario of the security guard re-identification under the real environment. The experimental results and comprehensive comparisons show a very promising performance of the proposed method.Publication Metadata only Copper complexes of 8-aminoquinoline and uracils as novel aromatase inhibitors(2017-08-01) Nujarin Sinthupoom; Virapong Prachayasittikul; Veda Prachayasittikul; Ratchanok Pingaew; Apilak Worachartcheewan; Supaluk Prachayasittikul; Somsak Ruchirawat; Mahidol University; Srinakharinwirot University; Chulabhorn Research Institute; Thailand Ministry of Education© 2017 Bentham Science Publishers. Currently, aromatase inhibitors (AIs) have been developed for the treatment of breast cancers and other estrogen-related conditions. However, searching for more and new classes of AIs is being investigated. 8-Aminoquinoline (8AQ) is an interesting scaffold to be explored. In particular, 8AQ as its mixed ligands (5-nitrouracil, 5Nu and 5-iodouracil, 5Iu) metal complexes are potential compounds to be studied. Objective: Metal complexes of 8AQ-5Nu/5Iu were investigated for aromatase inhibitory activity and cytotoxicity. Methods: Metal complexes (1-6) and free ligands were evaluated for aromatase inhibitory and cytotoxic activities. Aromatase inhibitory activity of the metal complexes was performed according to a guideline of BD Gentest™ kit using CYP19 enzyme and O-benzyl fluorescein (DBF) as a substrate. Cytotoxic effect of the compounds was tested against normal embryonic lung cell line (MRC) using the MTT assay. Results: Significantly, copper complexes 3 (IC50 = 0.7 μM) and 6 (IC50 = 1.7 μM) were shown to be active aromatase inhibitors with selectivity indices of 24.74 and16.40, respectively. Conclusion: Copper complexes of 8AQ-5Nu (3) and of 8AQ-5Iu (6) were highlighted as novel aromatase inhibitors that could be further developed for therapeutic applications.Publication Metadata only Combining over-sampling and under-sampling techniques for imbalance dataset(2017-02-24) Nutthaporn Junsomboon; Tanasanee Phienthrakul; Mahidol University© 2017 ACM. An important problem in medical data analysis is imbalance dataset. This problem is a cause of diagnostic mistake. The results of diagnostic affect to life of patients. If a doctor fails in diagnostic of patient who have disease that means he cannot treat patient in timely. However, the problem can be easily solved by adding or removing the data to closely balance for performance of diagnostic in medically. This paper proposed a solution to adjust imbalance dataset by combining Neighbor Cleaning Rule (NCL) and Synthetic Minority Over-Sampling Technique (SMOTE) techniques. The process of work is using NCL technique for removing sample data that are outliers in majority class and SMOTE technique is used for increasing sample data in minority class to closely balance dataset. After that, the balanced medical dataset is classified by Naïve Bayes, SMO and KNN algorithm. The experimental results show that the recall rate can be improved from the models that were created from balanced dataset.Publication Metadata only Cytotoxicity of three commercial orthodontic elastomeric ligature brands(2017-05-31) Peerapong Tua-Ngam; Nittaya Jira-Anankul; Niwat Anuwongnukroh; Surachai Dechkunakorn; Pasaree Laokijcharoen; Mahidol University; Faculty of Dentistry; Thailand National Metal and Materials Technology Center© The Authors, published by EDP Sciences, 2017. This study aimed to evaluate cytotoxicity of three commercial brands of orthodontic elastomeric ligatures. Materials and Methods: The three commercial orthodontic elastomeric ligature brands were C-brand, T-brand and U-brand from different manufacturing countries. The cytotoxic assay was performed using cell cultures (L929) which were subjected to the cell viability test with methyl-Tetrazolium (MTT). The L929 cell line was grown in 96-well tissue culture plates (1×105cells/cm3). Elastomeric ligatures (0.2 g) from each brand was placed in 1 ml of Minimum Essential Medium (MEM) at 37°C with 5% CO2at 100% humidity in an incubator for 24 hours. After incubation, the cell mitochondrial activity was evaluated by the MTT test for detecting viable cells from optical density according to ISO 10993-5: 2009 (E) test procedure. Cytotoxic effects were determined by the percentage of cell viability. Results: Microscopic investigation showed that all commercial elastomeric ligatures caused alterations in the fibroblast cell morphology from an elongated to a spherical form. The cell viability of C-brand, T-brand and U-brand were 51.10, 73.04 and 93.04%, respectively. Conclusion: T-brand and U-brand orthodontic elastomeric ligatures were non cytotoxic potential. U-brand had the greatest cell viability and C-brand had the lowest cell viability at 24 hours.Publication Metadata only Oleic acid Enhances Dengue Virus But Not Dengue Virus-Like Particle Production from Mammalian Cells(2017-10-01) Suwipa Ramphan; Sathiporn Suksathan; Nitwara Wikan; Puey Ounjai; Kanpong Boonthaworn; Poramate Rimthong; Tapanee Kanjanapruthipong; Suchin Worawichawong; Anan Jongkaewwattana; Nuttaporn Wongsiriroj; Duncan R. Smith; Mahidol University; Thailand National Center for Genetic Engineering and Biotechnology© 2017, Springer Science+Business Media, LLC. Despite the recent introduction of a commercial vaccine, the mosquito-transmitted dengue virus is still a worldwide public health problem. Based on the live attenuated vaccine strategy, the commercial vaccine has a less than optimal protective profile. Virus-like particles (VLPs) offer an attractive alternate vaccination strategy due to the effectively native presentation of epitopes in the absence of any infectious genetic material. However, the production of amounts of VLP in a platform that can support commercial development remains a major obstacle. This study generated two DENV 2 VLPs [codon-optimized and chimeric DENV/Japanese encephalitis virus (JEV)] and directly compared yields of these constructs by western blotting and dot blot hybridization. The effect of oleic acid supplementation, a process known to increase DENV production in natural infection, was also investigated. Results showed that the chimeric construct gave a two- to threefold higher yield than the codon-optimized construct and that while oleic acid increased DENV virion production in natural infection, it inhibited VLP production. These results suggest that further optimization of DENV VLP expression is possible, but it will require more understanding of how native DENV infection remodels the host cell machinery.