Sonkaew T.,Lampang Rajabhat University |
Macatangay R.,University of the Philippines at Diliman
Environmental Research Letters | Year: 2015
This study aims to determine the variability and trends of tropical biomass burning, tropospheric ozone levels from 2005-2012 in Thailand and the ozone transport from the surrounding regions. Intense biomass burning and tropospheric ozone in this area have a seasonal variability with the maximum generally occurring during the dry season. The northern part of Thailand was observed to have high tropospheric ozone during the dry peak season in April. Forward trajectory analysis determined that ozone sources due to biomass burning in the northern and western surrounding regions (Myanmar, Laos and India) enhance the tropospheric ozone column in northern Thailand. Seasonal variations were also seen for the middle and northeastern regions of Thailand. During August, most biomass burning occurs in Indonesia and Malaysia. However, forward trajectory analysis showed that the effect in the tropospheric ozone column level in the southern part of Thailand is minimal from these regions. Eight-year trends of tropospheric ozone column were also calculated for the different regions of Thailand. However, statistical analysis showed that these trends were not significant. The interannual variability of the tropospheric ozone column concentrations due to El Niño Southern Oscillation were also investigated. It was observed that the best correlation of the tropospheric ozone column with the Oceanic Niño Index (ONI) occured when ONI was advanced 3 months for the north, northeast and south regions of Thailand and 4 months for the middle region of Thailand. © 2015 IOP Publishing Ltd.
Pitchakarn P.,Chiang Mai University |
Ohnuma S.,U.S. National Institutes of Health |
Pintha K.,Chiang Mai University |
Pompimon W.,Lampang Rajabhat University |
And 2 more authors.
Journal of Nutritional Biochemistry | Year: 2012
Multidrug resistance (MDR) is a major factor in the failure of chemotherapy in cancer patients. Resistance to chemotherapy has been correlated to the overexpression of ABC drug transporters including P-glycoprotein (P-gp) that actively efflux chemotherapeutic drugs from cancer cells. Our previous study showed that bitter melon (Momordica charantia) leaf extract (BMLE) was able to reverse the MDR phenotype by increasing the intracellular accumulation of chemotherapeutic drugs. In the present study, bioguided fractionation was used to identify the active component(s) of BMLE that is able to modulate the function of P-gp and the MDR phenotype in a human cervical carcinoma cell line (KB-V1). We found that kuguacin J, one of the active components in BMLE, increased sensitivity to vinblastine and paclitaxel in KB-V1 cells. A flow cytometry assay indicated that kuguacin J inhibits the transport function of P-gp and thereby significantly increases the accumulation of rhodamine 123 and calcein AM in the cells. These results were confirmed by [ 3H]-vinblastine transport assay. Kuguacin J significantly increases intracellular [ 3H]-vinblastine accumulation and decreased the [ 3H]-vinblastine efflux in the cells. Kuguacin J also inhibited the incorporation of [ 125I]-iodoarylazidoprazosin into P-gp in a concentration-dependent manner, indicating that kuguacin J directly interacts with the drug-substrate-binding site on P-gp. These results indicate that kuguacin J modulates the function of P-gp by directly interacting at the drug-substrate-binding site, and it appears to be an effective inhibitor of P-gp activity in vitro and thus could be developed as an effective chemosensitizer to treat multidrug-resistant cancers. © 2012 Elsevier Inc.
Petsophonsakul P.,Chiang Mai University |
Pompimon W.,Lampang Rajabhat University |
Banjerdpongchai R.,Chiang Mai University
Asian Pacific Journal of Cancer Prevention | Year: 2013
Goniothalamin is an active compound extracted from Goniothalamus griffithii, a local plant found in northern Thailand. Goniothalamin inhibits cancer cell growth but is also toxic to normal cells. The aims of this study were to identify the cytotoxic effect of goniothalamin and the mechanism of cell death in human HL-60 and U937 cells. Cytotoxicity was determined by MTT assay and cell cycle profiles were demonstrated by staining with propidium iodide (PI) and flow cytometry. Apoptosis was confirmed by staining with annexin V-FITC/propidium iodide (PI) and flow cytometry. Reduction of mitochondrial transmembrane potential was determined by staining with dihexyloxacarbocyanine iodide and flow cytometry and expression of Smac, caspase-8 and -9 was demonstrated by Western blotting. Goniothalamin inhibited growth of HL-60 and U937 cell lines. An increase of SubG1 phase was found in their cell cycle profiles, indicating apoptosis as the mode of cell death. Apoptosis was confirmed by the flip-flop of phosphatidylserine using annexin V-FITC/PI assay in HL60 and U937 cells in a dose response manner. Furthermore, reduction of mitochondrial transmembrane potential was found in both cell types while expression of caspase-8, -9 and Smac/Diablo was increased in HL-60 cells. Taken together, our results indicate that goniothalamin-treated human leukemic cells undergo apoptosis via intrinsic and extrinsic pathways.
Banjerdpongchai R.,Chiang Mai University |
Wudtiwai B.,Chiang Mai University |
Pompimon W.,Lampang Rajabhat University
Asian Pacific Journal of Cancer Prevention | Year: 2014
Stigmalactam, an aristolactam-type alkaloid extracted from Orophea enterocarpa, exerts cytotoxicity against several human and murine cancer cell lines, but the molecular mechanisms remain elusive. The aims of this study were to identify the mode and mechanisms of human cancer cell death induced by stigmalactam employing human hepatocellular carcinoma HepG2 and human invasive breast cancer MDA-MB-231 cells as models, compared to normal murine fibroblasts. It was found that stigmalactam was toxic to HepG2 and MDA-MB-231 cells with IC50 levels of 23.0±2.67 μM and 33.2±4.54 μM, respectively, using MTT assays. At the same time the IC50 level towards murine normal fibroblast NIH3T3 cells was 24.4±6.75 μM. Reactive oxygen species (ROS) production was reduced in stigmalactam-treated cells dose dependently after 4 h of incubation, indicating antioxidant activity, measured by using 2',7',-dichlorohydrofluorescein diacetate and flow cytometry. Caspase-3 and caspase-9 activities were increased in a dose response manner, while stigmalactam decreased the mitochondrial transmembrane potential dose-dependently in HepG2 cells, using 3,3'-dihexyloxacarbocyanine iodide and flow cytometry, indicating mitochondrial pathway-mediated apoptosis. In conclusion, stigmalactam from O. enterocarpa was toxic to both HepG2 and MDA-MB-231 cells and induced human cancer HepG2 cells to undergo apoptosis via the intrinsic (mitochondrial) pathway.
Mulinta S.,Lampang Rajabhat University
Key Engineering Materials | Year: 2014
The objective of this study is to investigate the effect of red clay, grog and cement content (5,10,15,20%) on unfired clay brick's properties. The comparative properties of construction bricks produced by the community fulfilled the requirements of Thai industrial standard (TIS 77-2545) for brick processing in Small and Micro Community Enterprise of Clay Brick Making Group in Son Bun Reung village. The physical and mechanical properties were tested consisting of the volume shrinkage, bulk density, appearance porosity, moisture expansion, slaking, compressive and fractural strength. The result showed that physical-mechanical properties were improved by the addition of cement. The unfired clay brick consisting of 100% grog and 20% cement had 4.5% shrinkage value. The bulk density and appearance porosity were 1.77 g/cm2 and 3.5%, respectively. The fractural strength of unfired clay bricks was 41.2 kg/cm2. The compressive strength of unfired clay bricks was 282.4 kg/cm2. The clay bricks were not slaking. © (2014) Trans Tech Publications, Switzerland.
Ruammaitree K.,Lampang Rajabhat University
Key Engineering Materials | Year: 2014
The inspiration of the work was polka dot. It was a regulation of nature can be seen in shape and structure of living and non-living things. The ceramic products were decorated by used slip color before being left to dry at room temperature. The ceramic products were fired at 1230 °C in oxidation atmosphere. The ceramic products were appearance of slip dots that was slightly raised above surface gave ceramics are wonderful and interesting texture. © (2014) Trans Tech Publications, Switzerland.
Phoo-ngernkham T.,Khon Kaen University |
Chindaprasirt P.,Khon Kaen University |
Sata V.,Khon Kaen University |
Hanjitsuwan S.,Lampang Rajabhat University |
Hatanaka S.,Mie University
Materials and Design | Year: 2014
This article presents the effect of adding nano-SiO2 and nano-Al2O3 on the properties of high calcium fly ash geopolymer pastes. Nano-particles were added to fly ash at the dosages of 0%, 1%, 2%, and 3% by weight. The sodium hydroxide concentration of 10 molars, sodium silicate to sodium hydroxide weight ratio of 2.0, the alkaline liquid/binder ratio of 0.60 and curing at ambient temperature of 23°C were used in all mixtures. The results showed that the use of nano-SiO2 as additive to fly ash results in the decrease of the setting time, while the addition of nano-Al2O3 results in only a slight reduction in setting time. Adding 1-2% nano-particles could improve compressive strength, flexural strength, and elastic modulus of pastes due to the formation of additional calcium silicate hydrate (CSH) or calcium aluminosilicate hydrate (CASH) and sodium aluminosilicate hydrate (NASH) or geopolymer gel in geopolymer matrix. In addition, the additions of both nano-SiO2 and nano-Al2O3 enhances the shear bond strength between concrete substrate and geopolymer. © 2013 Elsevier Ltd.
Boonkorn P.,Lampang Rajabhat University
International Food Research Journal | Year: 2016
Mature-green tomato fruits were soaked in hot water for 10 minutes at 35, 40, 45 or 50°C and then stored at 13°C for 20 days. Untreated fruits were soaking with tap water (22°C). The study showed that exposing fruit to hot water influenced peroxidase (POD) and catalase (CAT) activities. Activity of the two enzymes increased with the increasing of soaking temperature, except for the 50°C treatment. Decay of tomato fruits reduced concurrently with increasing of POD and CAT activities. Polyphenol oxidase (PPO) activity in all hot water treatments decreased when compared to control and slightly increased at the end of storage period. Hot water treatment did not alter qualities of tomato fruits in terms of total soluble solids, titratable acidity and ascorbic acid. From the study, hot water treatment of tomato fruits at 40°C for 10 minutes before storage at 13°C was the most effective in activating antioxidant enzymes and reducing fruits decay. © All Rights Reserved.
Mulinta S.,Lampang Rajabhat University
Key Engineering Materials | Year: 2016
The purpose of the study was to investigate the effects of dolomite body, frit and potassium feldspar on the properties of color slip for decorative method of color slip on earthen ware production. The chemical composition of raw material was analyzed by X-ray fluorescence(XRF). The experiment started with triaxial blend of dolomite body, frit and potassium feldspar in the defined ratio and then to painting of color slips on specimen. After that, firing specimens at 950 °C in oxidation atmosphere. Finally, the specimens were tested microstructure and physical properties. The results showed that the ratio of 50% dolomite body, 40% frit and 10% potassium feldspar were optimum properties for decorative on earthenware body. In color slip consisting of blue color added cobalt oxide 1 wt%, green colors added chromic oxide 10 wt%, gray color added manganese oxide 10 wt%, yellow color added stain 2225 10 wt% and hazel color added ferric oxide 2 wt%. © 2016 Trans Tech Publications, Switzerland.
Numluk P.,Lampang Rajabhat University |
Chaisena A.,Lampang Rajabhat University
E-Journal of Chemistry | Year: 2012
The rapid development of the global alumina industry has led to a considerable increase in the production alumina and processing of alumina from non-bauxitic sources. Lampang clays comprise various minerals that contain about 22.70 wt% of extractable alumina. Local clay was ground, activated by calcination and treated with sulfuric acid to extract alumina. In the activation step, the effects of temperature and time on the extraction of alumina and iron were investigated. The leaching experiments were performed on clay samples with particle sizes less than 200 mesh. The samples were calcined at different temperatures, ranging from 450°C to 1050°C, and for different periods, ranging from 30 to 150 min. The optimum conditions for the extraction of alumina from Lampang clay include grinding the clay to pass through a 200 mesh sieve, calcining the ground clay at 750°C for 30 min, extracting the alumina from the calcined clay by leaching with 3M sulfuric acid, and using an acid to clay ratio of 80 wt% at 100°C for 120 min. An aluminum dissolution efficiency of 95.1 % was achieved under the conditions that resulted in the maximum dissolution efficiency of iron (26.6 %).