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Publication Open Access Sensitivity and specificity of PS/AA-modified nanoparticles used in malaria detection(2012-11) Raweewan Thiramanas; Kulachart Jangpatarapongsa; Udom Asawapirom; Pramuan Tangboriboonrat; Duangporn Polpanich; Center for Innovation Development and Technology Transferand affinity binding via streptavidin (SA) and biotin interaction, were employed. The optimum ratio of Ab to NPs used in each immobilization procedure and the latex agglutination test based on the reaction between Ab conjugated NPs and malaria patient plasmaPublication Open Access The removal of colors in non-carbonated soft drinks using granular activated carbon for coliform bacteria detection by sanitary indicator medium(2009) Vatanasomboon, P; Pisit Vatanasomboon; Rojanavipart, P; Piangchan Rojanavipart; Luksamijarulkul, P; Pipat Luksamijarulkul; พิศิษฐ์ วัฒนสมบูรณ์; เพียงจันทร์ โรจนวิภาต; พิพัฒน์ ลักษมีจรัลกุล; Srisantisang, N; Mahidol University. Faculty of Public Health. Department of Environmental Health Science; Mahidol University. Faculty of Public Health. Department of Biostatistics; Mahidol University. Faculty of Public Health. Department of Microbiologyfor blue color-tone. The validity of coliform bacteria detection by SI medium for these removed-color soft drinks when compared with the standard MPN method were sensitivity value, specificity value and efficiency of test of more than 80%. Thus, GAC can...ที่สุดสำหรับเครื่องดื่มสีฟ้า เมื่อหาค่าความถูกต้อง (validity) ของการตรวจโคลิฟอร์มแบคทีเรียด้วย SI medium ในเครื่องดื่มที่ถูกกำจัดสีออกด้วยสภาวะที่เหมาะสมที่สุด เปรียบเทียบกับวิธีมาตรฐาน MPN ได้ค่า sensitivity, specificity และ efficiency of test มากกว่า 80Publication Open Access Cytotoxicity evaluation of Clinacanthus nutans through dimethylthiazol diphenyltetrazolium bromide and neutral red uptake assays.(2016-01) Suwanna Korsuwannawong; สุวรรณา ก่อสุวรรณวงศ์; La‑Ongthong Vajrabhaya; ละอองทอง วัชราภัย; Suwanna Korsuwannawong; Mahidol University. Faculty of Dentistry. Research OfficeObjectives: The aim of this study was to compare the results of dimethylthiazol diphenyltetrazolium bromide (MTT) and neutral red uptake (NRU) assays of Clinacanthus nutans cytotoxicity. Materials and Methods: Mouse fibroblast (L929) cells were exposed to 0.01%, 0.1%, 0.25%, and 0.5% (W/V) C. nutans in a 96-cluster -well-culture plate for 24 h. The cell viability after exposure to C. nutans was determined by MTT and NRU assays in separate tissue culture plates. The two assays were compared through an intra‑class correlation coefficient (ICC) analysis. Results: No significant differences in cytotoxicity were noted between the two assays ( P > 0.05). The ICC values for agreement between two assays for the negative and positive control groups and C. nutans concentrations of 0.01%, 0.1%, 0.25%, and 0.5% were 0.84, 0.83, 0.77, 0.68, 0.74, and 0.71, respectively. Conclusion: In general, the MTT and NRU assays performed similarly, exhibiting moderate to good correlation for the evaluation of the cytotoxicity of C. nutans .Publication Open Access FlexiChip package: an universal microarray with a dedicated analysis software for high-thoughput SNPs detection linked to anti-malarial drug resistance.(2009-10-15) Steenkeste, Nicolas; Dillies, Marie-Agnès; Khim, Nimol; Sismeiro, Odile; Chy, Sophy; Lim, Pharath; Crameri, Andreas; Bouchier, Christiane; Mercereau-Puijalon, Odile; Beck, Hans-Peter; Mallika Imwong; มัลลิกา อิ่มวงศ์; Dondorp, Arjen M.; Socheat, Duong; Rogier, Christophe; Coppée, Jean- Yves; Ariey, Frédéric; Steenkeste, Nicolas; Mahidol University. Faculty of Tropical MedicineBACKGROUND: A number of molecular tools have been developed to monitor the emergence and spread of anti-malarial drug resistance to Plasmodium falciparum. One of the major obstacles to the wider implementation of these tools is the absence of practical methods enabling high throughput analysis. Here a new Zip-code array is described, called FlexiChip, linked to a dedicated software program, which largely overcomes this problem. METHODS: Previously published microarray probes detecting single-nucleotide polymorphisms (SNP) associated with parasite resistance to anti-malarial drugs (ResMalChip) were adapted for a universal microarray FlexiChip format. To evaluate the overall sensitivity of the FlexiChip package (microarray + software), the results of FlexiChip were compared to ResMalChip microarray, using the same extension probes and with the same PCR products. In both cases, sequence results were used as gold standard to calculate sensitivity and specificity. FlexiChip results obtained with a set of field isolates were then compared to those assessed in an independent reference laboratory. RESULTS: The FlexiChip package gave results identical to the ResMalChip results in 92.7% of samples (kappa coefficient 0.8491, with a standard error 0.021) and had a sensitivity of 95.88% and a specificity of 97.68% compared to the sequencing as the reference method. Moreover the method performed well compared to the results obtained in the reference laboratories, with 99.7% of identical results (kappa coefficient 0.9923, S.E. 0.0523). CONCLUSION: Microarrays could be employed to monitor P. falciparum drug resistance markers with greater cost effectiveness and the possibility for high throughput analysis. The FlexiChip package is a promising tool for use in poor resource settings of malaria endemic countries.Publication Open Access L-carnitine supplemented extender improves cryopreserved-thawed cat epididymal sperm motility(2014-06) Manee-In S; Parmornsupornvichit S; Kraiprayoon S; Tharasanit T; Chanapiwat P; Kaeoket K; Mahidol University. Faculty of Veterinary Science. Department of Clinical Sciences and Public Health Medicinesperm quality following cryopreservation and thawing. After routine castration, cauda epididymides were collected from 60 cat testes. The epididymal spermatozoa from 3 cauda epididymides were pooled as 1 replicate. Spermatozoa samples (16 replicatesPublication Open Access CD2068 potentially mediates multidrug efflux in Clostridium difficile(2017) Chawalit Ngernsombat; Suthasinee Sreesai; Phurt Harnvoravongchai; Surang Chankhamhaengdecha; Tavan Janvilisri; Mahidol University. Faculty of Science. Department of Biochemistry; Mahidol University. Faculty of Science. Department of BiologyClostridium difficile is a major cause of antibiotic-associated diarrhea and the treatment thereof becomes more difficult owing to a rise of multidrug resistant strains. ATP-binding cassette (ABC) transporters are known to play a crucial role in the resistance to multiple antibiotics. In this study, the potential contribution of an ABC transporter in C. difficile multidrug resistance was investigated. The expression level of the cd2068 gene in C. difficile encoding an ABC transporter was up-regulated following the exposure to certain antibiotics compared to the control cells. Heterologous expression of CD2068 in Escherichia coli revealed that it mediated the efflux of fluorescent substrates and conferred resistance to multiple drugs. The CD2068-associated ATPase activity in membrane vesicles was also stimulated by various antibiotics. Furthermore, the insertional inactivation of the cd2068 gene in C. difficile led to a significant increase in susceptibility to antibiotics, which could be genetically complemented, supporting that CD2068 was directly associated to the drug resistance. These results demonstrate the potential role for the ABC transporter CD2068 in the resistance mechanism against multiple drugs in C. difficile.Publication Open Access Novel adiponectin variants identified in type 2 diabetic patients reveal multimerization and secretion defects(2011) Prapaporn Jungtrakoon; Nattachet Plengvidhya; Watip Tangjittipokin; Sarin Chimnaronk; Wanisa Salaemae; Nalinee Chongjaroen; Kanjana Chanprasert; Jatuporn Sujjitjoon; Chatchawan Srisawat; Pa-thai Yenchitsomanus; Mahidol University. Faculty of Medical Technology. Department of Clinical Microscopy; Mahidol University. Faculty of Medicine Siriraj Hospital. Department of Medicine; Mahidol University. Institute of Molecular Biosciences.ADIPOQ, encoding adiponectin, is a candidate gene for type 2 diabetes (T2D) identified by genome-wide linkage analyses with supporting evidence showing the protein function in sensitizing insulin actions. In an endeavor to characterize candidate genes causing T2D in Thai patients, we identified 10 novel ADIPOQ variations, several of which were non-synonymous variations observed only in the patients. To examine the impact of these non-synonymous variations on adiponectin structure and biochemical characteristics, we conducted a structural analysis of the wild-type and variant proteins by in silico modeling and further characterized biochemical properties of the variants with predicted structural abnormalities from the modeling by molecular and biochemical studies. The recombinant plasmids containing wild-type and variant ADIPOQ cDNAs derived from the variations identified by our study (R55H, R112H, and R131H) and previous work (G90S and R112C) were constructed and transiently expressed and co-expressed in cultured HEK293T cells to investigate their oligomerization, interaction, and secretion. We found that the novel R55H variant impaired protein multimerization but it did not exert the effect over the co-expressed wild-type protein while novel R131H variant impaired protein secretion and also affected the co-expressed wild-type protein in a dominant negative fashion. The R131H variant could traffic from the endoplasmic reticulum to the Golgi, trans-Golgi network, and early endosome but could not be secreted. The R131H variant was likely to be degraded through the lysosomal system and inhibition of its degradation rescued the variant protein from secretion defect. We have shown the possibility of using in silico modeling for predicting the effect of amino acid substitution on adiponectin oligomerization. This is also the first report that demonstrates a dominant negative effect of the R131H variant on protein secretion and the possibility of using protein degradation inhibitors as therapeutic agents in the patients carrying adiponectin variants with secretion defect.Publication Open Access Shear bond strength of Zirconia to different adhesive resin cements.(2015-05) Porntida Visuttiwattanakorn; พรธิดา วิสุทธิวัฒนากร; Noi Rithy; Kallaya Suputtamonkol; กัลยา ศุพุทธมงคล; Widchaya Kanchanavasita; วิชญ กาญจนะวสิต; Mahidol University. Faculty of Dentistry. Prosthodontic Departmentof the square and cylinder-shaped blocks were sandblasted with 50 μm Al2O3 at 2-bar pressure. After bonding, specimens were stored in distilled water at 37 ˚C for 24 hrs and then shear bond test was performed using a universal testing machine. The bond... strength data were analyzed using an independent t-test at α = 0.05. Results: There was no significant difference between shear bond strength of either RelyXTM Ultimate (17.2 ± 6.0 MPa) or PanaviaTM F 2.0 (15.8 ± 4.4 MPa) bonded to zirconia. The failurePublication Open Access Biochemical and functional characterization of Plasmodium falciparum DNA polymerase δ(2016) Jitlada Vasuvat; Atcha Montree; Sangduen Moonsom; Ubolsree Leartsakulpanich; Songsak Petmitr; Federico Focher; Wright, George E.; Porntip Chavalitshewinkoon‑Petmitr; Mahidol University. Faculty of Tropical Medicine. Department of Protozoologyand identified by LC–MS/MS. PfPolδ-cat was biochemically characterized. The roles of PfPolδS and PfPCNA in PfPolδ-cat function were investigated. In addition, inhibitory effects of 11 compounds were tested on PfPolδ-cat activity and on in vitro parasite growthPublication Open Access การบำบัดน้ำเสียหมึกพิมพ์เฟล็กโซกราฟีชนิดใช้น้ำเป็นตัวทำลาย โดยใช้ฝุ่นจากเตาหลอมไฟฟ้า(2551) โสภา ชินเวชกิจวานิชย์; วัลภา คุปต์กาญจนกุล; Sopa Chinwetkitvanich; Wallapa Kupkanchanakul; โสภา ชินเวชกิจวานิชย์; มหาวิทยาลัยมหิดล. คณะสาธารณสุขศาสตร์. ภาควิชาวิศวกรรมสุขาภิบาลการศึกษานี้ มีวัตถุประสงค์เพื่อบำบัดน้ำเสียที่เกิดจากการพิมพ์ในระบบเฟล็กโซกราฟีโดยใช้ฝุ่นจากเตาหลอมไฟฟ้า (EAF dust) ทำการศึกษาหาสภาวะที่เหมาะสมโดยแปรค่าพีเอชตั้งแต่ 5-8 ปริมาณฝุ่นจากเตาหลอมไฟฟ้า 0-05 กรัมต่อลิตร และระยะเวลาการกวนผสม 5-30 นาที ผลการทดลองพบว่า พีเอชเป็นปัจจัยที่มีบทบาทมากที่สุดต่อประสิทธิภาพการลดสีและซีโอดี นั่นคือ ในสภาวะที่เป็นกรด (พีเอชต่ำกว่า 7 เล็กน้อย) พบว่าปริมาณฝุ่นจากเตาหลอมไฟฟ้าที่เติมให้เพิ่มขึ้นและการเพิ่มระยะเวลาการกวนผสมไม่ได้ทำให้ประสิทธิภาพการบำบัดน้ำเสียเพิ่มขึ้นอย่างมีนัยสำคัญ ในชุดการทดลองที่พีเอชเป็นกลาง (พีเอชของน้ำเสียเอง) พบว่าการเติมฝุ่นจากเตาหลอมไฟฟ้าให้เพิ่มขึ้น (0-50 กรัมต่อลิตร) ส่งผลให้ประสิทธิภาพการลดสี ซีโอดี และของแข็งแขวนลอยเพิ่มขึ้น แต่การเพิ่มระยะเวลาการกวนผสมมีผลกระทบน้อยมาก ประสิทธิภาพการลดสีซีโอดี และของแข็งแขวนลอยสูงสุดที่ร้อยละ 99, 88 และ 97 ตามลำดับ เมื่อใช้ปริมาณฝุ่นจากเตาหลอมไฟฟ้า 40 กรัมต่อลิตร และใช้เวลาในการกวนผสมเพียง 5 นาทีก็เพียงพอ ผลการวิเคระห์พื้นที่ผิวจำเพาะของฝุ่นจากเตาหลอมไฟฟ้าพบว่ามี 0.6 ตารางเมตรต่อกรัม (ด้วยเทคนิค BET ที่ใช้ไนโตรเจนเหลว) ซึ่งถือว่าฝุ่นจากเตาหลอมไฟฟ้านี้มีพื้นที่ผิวน้อยมากไม่เหมาะที่จะเป็นสารดูดซับ ดังนั้น คาดว่ากลไกในการบำบัดน้ำเสียน่าจะเป็นกระบวนการโคแอกกูเลชันมากกว่ากระบวนการดูดซับ This experimental study focuses on the treatability of effluents generated from a water- based ink industry by using electric arc furnace (EAF) dust. The optimum condition, was therefore investigated by variations of EAF dust dosages in the range of 0 to 50 g/l, pH of 5 to 8, and of mixing times (contact time) of 5 to 30 min. The results showed that pH played a significant role in both color and COD removals. Under acidic condition (pH lower than 7), the addition of EAF dust and increase of mixing times did not enhance the treatability significantly. While in the case of neutral pH level (the pH range of wastewater itself), the increase of EAF dust dosages from 0 to 50 g/l significantly affected the treatability, but the effect of mixing times was still small. The maximum removal efficiencies of color, COD, and SS were 99%, 88% and 97%, respectively, when using EAF dust dosage of 40 g/l with mixing time of 5 min. In addition, the specific surface area of EAF dust was about 0.6 m2/g (by BET technique with liquid nitrogen), which was considered to be a too small amount of surface area to be considered as a proper adsorbent. Therefore, the mechanisms of those removals would presumably be because of coagulation rather than by adsorption.