Papers by Pornanong Aramwit
Journal of Traditional and Complementary Medicine, 2021
Background Hyperpigmentation is a skin disorder, which is caused by an excess production of melan... more Background Hyperpigmentation is a skin disorder, which is caused by an excess production of melanin. The reduction in melanin content without causing undesirable effects is required for the treatment of hyperpigmentation. Sericin is increasingly used as a hyperpigmentation treatment because of its antityrosinase activity. However, the various methods of sericin extraction have an effect on the composition and biological properties. The purpose of this study was to investigate the antioxidant and anti-melanogenic properties of sericin using different extraction methods including acid, base, heat, and urea extraction. Methods The chemical properties of extracted sericin were assessed in terms of amino acid components, thermal behavior, and UV–vis absorption. The inhibitory effects of sericin on melanogenesis were explored by determining the melanin content and cellular tyrosinase activity in B16F10 cells. Results Sericin from urea extraction provided different properties when compared with the other extraction methods. Our results indicate that urea-extracted sericin reduced the melanin content and cellular tyrosinase activity more effectively than the other extraction methods. Interestingly, the potential anti-melanogenic activity was more effective than kojic acid, a depigmenting agent used to treat hyperpigmentation. Moreover, treatment of urea-extracted sericin induced reactive oxygen species and subsequently activated antioxidant activity in B16F0 cells. Conclusions Our results present the potential inhibitory effect of urea-extracted sericin on melanogenesis. The therapeutic potential of urea-extracted sericin can be used in the treatment of hyperpigmentation and its complications.
Journal of Biomaterials Science-polymer Edition, Oct 3, 2021
Abstract Hydroxyapatite (HA or HAp) is one of the most preferred biomaterials, specifically for b... more Abstract Hydroxyapatite (HA or HAp) is one of the most preferred biomaterials, specifically for bone tissue engineering. HAp is available naturally and is also chemically synthesized. The properties, shape, size and crystalline structure and applications of HAp vary widely depending on the source and extraction methods used. In addition to conventional chemical approaches such as precipitation or sol-gel techniques, newer methods such as microwave synthesis and atomic-layer deposition provide an opportunity to generate HAp with desirable structure and properties. Various methods used for the synthesis of HAp have their own pros and cons. Hence, it is essential to understand the role of specific methods and conditions on the properties and structure of HAps in order to obtain HAp with properties suitable for specific applications. In addition to pure HAp, substantial efforts have been made to dope HAp with various minerals or bioentities to enhance their suitability for medical, environmental remediation and other approaches. In this review, we provide an overview of the various chemical methods used to produce HAp, properties of the HAp produced and its potential applications. Particular focus of this paper is on the co-relation between properties and processes used to synthesis HAp. This review will enable readers to quickly understand the importance of synthesis methods and conditions on the properties of HAp and choose appropriate means to generate HAp with desired properties for specific applications. Graphical Abstract
International Journal of Molecular Sciences
The noncontagious immune-mediated skin disease known as psoriasis is regarded as a chronic skin c... more The noncontagious immune-mediated skin disease known as psoriasis is regarded as a chronic skin condition with a 0.09–11.4% global prevalence. The main obstacle to the eradication of the disease continues to be insufficient treatment options. Sericin, a natural biopolymer from Bombyx mori cocoons, can improve skin conditions via its immunomodulatory effect. Many external therapeutic methods are currently used to treat psoriasis, but sericin-based hydrogel is not yet used to treat plaques of eczema. Through the use of an imiquimod rat model, this study sought to identify the physical and chemical characteristics of a silk sericin-based poly(vinyl) alcohol (SS/PVA) hydrogel and assess both its therapeutic and toxic effects on psoriasis. The cytokines, chemokines, and genes involved in the pathogenesis of psoriasis were investigated, focusing on the immuno-pathological relationships. We discovered that the SS/PVA had a stable fabrication and proper release. Additionally, the anti-infla...
Biofuels, Bioproducts and Biorefining
Extraction of oil from Azadirachta indica generates oil cake (meal) containing proteins and carbo... more Extraction of oil from Azadirachta indica generates oil cake (meal) containing proteins and carbohydrates. The proteins in neem oil cake with antimicrobial and antioxidant properties have been made into films and studied for their properties and potential applications. Neem oil cakes are available in large quantities at low cost but are non‐edible and have limited applications. Currently, most of the neem oil cakes are used as fertilizers. Neem oil cakes contain about 25–30% proteins and 30–40% carbohydrates, which are valuable. Proteins in the neem oil cake could be suitable for food, medical, biotechnology, and other applications. However, there are no reports on the properties or applications of proteins in neem meal. In this study, a simple alkaline process was used to extract proteins from the oil meal and the proteins obtained were converted into films. The films were crosslinked with citric acid (CA) to improve mechanical properties and stability in aqueous conditions. Neem p...
EXCLI Journal, 2019
Previous studies proved the pro-angiogenic effect of Crocetin, a natural carotenoid dicarboxylic ... more Previous studies proved the pro-angiogenic effect of Crocetin, a natural carotenoid dicarboxylic acid, in both in vivo and in vitro models. However, the exact mechanism of Crocetin action has not completely been elucidated yet. The current experiment was designed to find the activity of PI3K-Akt-eNOS axis after the treatment of endothelial cells with Crocetin in vitro. Human Umbilical Vein Endothelial Cells (HUVECs) were incubated with various concentrations of Crocetin (1, 5, 25, 50, and 100 µM) over a period of 72 h. Crocetin significantly increased HUVECs viability after 72 h as compared with the control group. We also found that Crocetin promoted the formation of the capillary-like structure compared to the control (p<0.05). Moreover, an improved migration rate and increased MMP-9 activity were observed in HUVECs that received 50 µM Crocetin (p<0.05). Crocetin enhanced the uptake of Ac-LDL which is correlated with increased lipid metabolism. Based on the data from the curr...
Journal of Traditional and Complementary Medicine, 2021
Background and aim Psoriasis is a skin disorder that leads to chronic inflammation and keratinocy... more Background and aim Psoriasis is a skin disorder that leads to chronic inflammation and keratinocyte hyperproliferation. Sericin extracted from Bombyx mori cocoon has been demonstrated to possess anti-inflammatory and antiproliferative properties, which makes it a viable candidate for psoriasis treatment. This study aimed to investigate the therapeutic effect of sericin on skin psoriasis at the cellular level. Experimental procedure Imiquimod-induced skin psoriasis was established in Sprague-Dawley rats. The rats with psoriasis were divided into 6 groups (n = 5), namely, one nontreatment control group and five groups that received different treatments: sericin (2.5%, 5%, and 10%), 0.1% betamethasone, 3 μg/ml calcitriol. The treatments were administered twice daily for 7 days, followed by skin sample collection. Epidermal improvement and protein expression were evaluated using histopathological and label-free proteomic approaches and immunohistochemistry. Results and conclusion Compared with other concentrations, 10% sericin had the desired effect of improving skin psoriasis as shown by reduced epidermal thickness, similar to the effects of betamethasone and calcitriol treatments. Anti-inflammatory activity was shown by decreased C–C motif chemokine 20 (CCL20) expression posttreatment. Proteomic observation revealed that sericin reduced cytokine production by Th17 cells by interfering with the JAK-STAT signaling pathway. Sericin treatment also resulted in a modulated immune response via upregulation of Galectin-3 (Lgals3) and downregulation of Sphingosine-1-phosphate lyase1 (Sgpl1). Sericin improved epithelial cell proliferation by upregulating Nucleoside diphosphate kinase B (Nme2). Therefore, the therapeutic effect of sericin on psoriasis correlated with a reduced immune response and attenuated epidermal proliferation, making sericin a promising approach for skin psoriasis treatment.
Trends in Biotechnology, 2020
Silk has remained the most preferred protein fiber since its discovery in 3000 BC. However, the c... more Silk has remained the most preferred protein fiber since its discovery in 3000 BC. However, the cost, availability, and resources required to rear the silkworms and process silk are imposing considerable constraints on the future of silk. It is often unrealized that apart from the fibers, production and processing of silk are a source for a diverse range of sustainable, biodegradable, and biocompatible polymers. Hence, delineating itself from being the primary source of protein fibers for millenniums, the silk industry worldwide is transitioning into a biobased industry and as a source for pharmaceuticals, biomaterials, cosmetics, food, and energy. Toward this, byproducts (BPs) and co-products (CPs) that are inevitably generated are now being considered to be of immense economic value and could be up to 10 times more valuable than the silk fibers. Here, we elucidate the properties and potential applications of silk BPs and CPs to present the true potential of silkworms and to promote the establishment of silkwormbased bioeconomy and biorefineries. Silk beyond the Fibers Although discovered accidentally in China, the journey of silk has been fascinating and silk has played an important role in the social and economic status and political implications across the globe for more than 5000 years. Treasured for its elegance and unparalleled virtues, silk and silk products have graced the royals and the commons equally. Silk has been one of the most traded textile materials and continues to play a crucial role in the geopolitical events even today. Despite only two countries (China and India) and one species of silkworm (Bombyx mori; Box 1) producing more than 90% of the world's silk fibers, silk-based products are extensively used worldwide not only for apparel and textiles but also for medical and other applications. Throughout its history, considerable technical, economical, and social challenges have been overcome to ensure the legacy and importance of silk. However, the focus of the silk industry has been to rise production of silk, decrease costs, and develop exquisite products and increase the applicability and acceptance of silk. Although the dominance of silk as a preferred fiber continues, silk and silk industries face numerous challenges. Increasing costs, issues in quality, changing climatic conditions, and constraints in availability of resources are imposing unseen restrictions on the rearing (see Glossary), production, processing, and selling of silk and silk products. There has been considerable decrease in the growth and value addition of silk and silk goods in the last decade or so. To overcome these challenges, the silk industry is actively seeking new avenues of expanding beyond fibers and fibrous applications. Highlights Silkworms are biofactories that generate proteins, lipids, and polysaccharides. Sericin, pupae, litter, and mulberry leaves contain valuable biomolecules.
Scientific Reports, 2020
Psoriasis is mainly caused because of inappropriate immune responses in the epidermis. Rice (Oryz... more Psoriasis is mainly caused because of inappropriate immune responses in the epidermis. Rice (Oryza sativa L.: SRNC05053-6-2) consists of anthocyanin, which exhibits strong antioxidative and anti-inflammatory properties. This study aimed to evaluate the role of this black-coloured rice crude extract in alleviating the symptoms of psoriasis using human psoriatic artificial skin and an imiquimod-induced rat psoriasis model. Psoriasis-related genes, cytokines and chemokines were examined; in addition, the antioxidative and anti-inflammatory properties and the immunohistopathological features of this condition were studied. The results showed that the rice extract reduced the severity of psoriasis by (1) decreasing the epidermal thickness, acanthosis, hyperkeratosis, epidermal inflammation and degree of apoptosis induction via caspase-3, (2) increasing the expression levels of anti-inflammatory cytokines (IL-10 and TGF-β), (3) reducing the levels of pro-inflammatory cytokines (IL-6, IL-8...
Research in Pharmaceutical Sciences, 2020
Background and purpose: Crocetin is a natural antioxidant that is found in the crocus flower and ... more Background and purpose: Crocetin is a natural antioxidant that is found in the crocus flower and Gardenia jasminoides (fruit). Previous studies have reported its anticancer activity both in vivo and in vitro. In addition, crocetin suppresses the growth and migration of human colorectal cancer cells, however, its mechanism of action remains to be elucidated. Therefore, the present study investigated the molecular mechanism of crocetin effect on colorectal cancer cells (HCT-116) in vitro. Experimental approach: HCT-116 cells were treated with different concentrations (0, 200, 400, 600, and 800 μM) of crocetin for 24 h. The cell survival rate was measured by MTT assay. Cell migration capacity was evaluated using the wound healing assay. The expression levels of vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP-9) was monitored by RT-PCR. Phosphorylation of focal adhesion kinase (FAK) and p38 mitogen-activated protein kinase (MAPK) was determined using western blot. Findings/Results: The proliferation of HCT-116 was inhibited by crocetin at 800 μM (P < 0.001). Crocetin prevented migration of HCT-116 cells (P < 0.05) and suppressed VEGF and MMP-9 mRNA expression (P < 0.001) and increased phosphorylation of p38 (MAPK; P < 0.001). However, no significant change in the phosphorylation of FAK was observed. Conclusion and implication: These data suggested that crocetin-induced growth-and migrationsuppressing effects on HCT-116 cells may partially depend on the regulation of the p38 (MAPK) signaling pathway.
Advances in Wound Care, 2019
Objective: To fabricate and investigate the properties of fibroin and polyvinyl alcohol (PVA) hyd... more Objective: To fabricate and investigate the properties of fibroin and polyvinyl alcohol (PVA) hydrogels containing sericin prepared using high-pressure carbon dioxide (CO 2). Approach: In this study, fibroin/PVA hydrogels with and without sericin were prepared using the high-pressure CO 2 method. The physical and mechanical properties of the hydrogels were investigated using field-emission scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry, and the swelling, water retention, and compressive properties were assessed. Results: The hydrogels obtained from the combination of fibroin and PVA presented a compositional gradient along the hydrogel thickness and structure. The upper layer of the hydrogel consisted of a fibroin-based hydrogel blended with PVA, whereas the lower layer contained only fibroin. The mechanical properties regarding compression of the fibroin/PVA hydrogel were significantly better than those of the pure fibroin hydrogel, for hydrogels with and without sericin. Moreover, the mechanical properties of the hydrogels with sericin were significantly better than those without sericin. The water contents of all samples were >90%. Innovation: This study assessed a new combination of a wound healing agent and a biomaterial dressing. Moreover, this hydrogel production technique used a clean method without the need for a chemical crosslinking agent. Conclusion: The combination of the fibroin and PVA hydrogel and sericin prepared using the high-pressure CO 2 method led to good physical properties. This material may be a candidate for medical applications.
European Journal of Clinical Microbiology & Infectious Diseases, 2018
The use of topical antimicrobials is beneficial for infection control in wound care because wound... more The use of topical antimicrobials is beneficial for infection control in wound care because wound infection is the major cause of delayed healing. The advantages of topical over systemic antimicrobials include a higher concentration at the target site, fewer systemic adverse effects, and a lower incidence of antimicrobial resistance. Nowadays, topical antimicrobials are divided into three groups: disinfectants, antiseptics, and antibiotics. Only antiseptics and antibiotics can be applied to living skin; therefore, this review will focus only on these groups. The advantages of each topical antimicrobial are well established; however, their disadvantages remain prominent. It is widely known that antiseptics show higher cytotoxicity and a broader spectrum of activity than antibiotics, whereas antibiotics show a higher probability of bacterial resistance development. However, there are still many adverse effects, resulting from each topical antimicrobial. This review aims to summarize the possible adverse effects of commonly used antiseptics (biguanide, silver, iodine, chlorine compounds, and other antiseptics), antibiotics (bacitracin, mafenide, mupirocin, neomycin, and silver sulfadiazine), and natural antimicrobials (curcumin and honey). Moreover, the antimicrobials that should be avoided in particular populations are also summarized in this review in order to increase awareness for antimicrobial selection in those populations.
Express Polymer Letters, 2019
Keratin, a fibrous structural protein, is the major component of hair (approximately 95 wt% in wo... more Keratin, a fibrous structural protein, is the major component of hair (approximately 95 wt% in wool [1]), feathers (approximately 90 wt% [2]), and the outer layer of skin, nails, horns and beaks. According to its structure and function, keratin is categorized into two groups with-i) low sulfur content (soft keratin) and ii) high sulfur content (hard keratin) [3-5]. The former is the crucial structural component of epithelial tissues [6], whereas the latter is found in nails and beaks. Different from other fibrous proteins, keratin contains high amounts of cysteine (7-20% of total amino acid residues) [7, 8], mostly localized at the terminal regions of the protein [9, 10]. Similar to other biopolymers, the intrinsic biocompatibility [11-13], biodegradability [14, 15], and natural abundance of keratin make it a valuable candidate for biomedical and tissue engineering applications [16, 17]. The presence of the primary amino acid sequence of cellular-binding motifs, i.e. RGD (Arg-Gly-Asp), in
Gene, 2018
Many phyto-compounds are found to have anti-angiogenesis property. Curcumin, a natural polyphenol... more Many phyto-compounds are found to have anti-angiogenesis property. Curcumin, a natural polyphenol, has been used as medicinal plant for years with different biological activities. Here, we investigated the effect of curcumin on angiogenesis potential of human endothelial cells. Human Umbilical Vein Endothelial Cells (HUVECs) were treated with different concentration of curcumin over a period of 72 h. Cell survival rate was measured by MTT assay. Cell migration and tubulogenesis were studied by scratch and tubulogenesis assays. The expression level of VEGF was monitored by RT-PCR. We also monitored the phosphorylation of FAK and P-38 MAPK by western blotting. Compared to control group, curcumin decreased HUVECs survival rate after 72 h. We found that the migration of HUVECs was decreased after curcumin treatment compared to the control (p<0.0001). Cell alignment and tubulogenesis activity were found to be inhibited compared to cells from the VEGF group (p<0.05). The expression level of VEGF was increased in curcumin treated cells at first 24 h time period. Based on data from the current experiment, the protein level of p-FAK/FAK ratio was increased coincided with a decrease in p-P38/P38 ratio treatment with curcumin (p<0.0001). These data demonstrated that curcumin inhibited HUVECs angiogenesis potential by modulation of FAK/ P-38 MAPK signaling pathway.
Archives of Dermatological Research, 2018
Bacterial cellulose wound dressings containing silk sericin and PHMB (BCSP) were developed in our... more Bacterial cellulose wound dressings containing silk sericin and PHMB (BCSP) were developed in our previous studies. It had good physical properties, efficacy, and safety. For further use as a medical material, this dressing was investigated for its efficacy and safety in split-thickness skin graft (STSG) donor-site wound treatment compared to Bactigras® (control). Moreover, the inflammatory responses to both dressings were also deeply investigated. For in vivo study, expressions of antiinflammatory cytokines were intensely considered in the tissue interfacing area. The result showed that IL-4 and TGF-β from BCSP-treated tissue had advantages over Bactigras®-treated tissue at 14 and 21 days post-implantation. For clinical study, a single-blinded, randomized controlled study was generated. The half of STSG donor site wound was randomly assigned to cover with BCSP or Bactigras®. Twenty-one patients with 32 STSG donor site wounds were enrolled. The results showed that wound-healing time was not significantly different in both dressings. However, wound quality of BCSP was better than Bactigras® at healing time and after 1 month (p < 0.05). The pain scores of BCSP-treated wound were statistically significant lower than Bactigras®-treated wound (p < 0.05). No sign of infection or adverse event was observed after treatment with both dressings. In conclusion, the inflammation responses of the dressing were clearly clarified. The advantages of BCSP were wound-quality improvement, pain reduction, and infection protection without adverse events. It was fit to be used as the alternative treatment of STSG donor site wound.
Journal of Bioactive and Compatible Polymers, 2016
Gamma irradiation was used to fabricate crosslinked poly(vinyl alcohol)/sericin hydrogels with di... more Gamma irradiation was used to fabricate crosslinked poly(vinyl alcohol)/sericin hydrogels with different sericin concentrations, and the physicochemical and biological properties of the gamma-irradiated poly(vinyl alcohol)/sericin hydrogels were characterized. Following gamma irradiation, the hydrogels had a high gel fraction (80%–95%), implying a high degree of crosslinking. Fourier transform infrared spectra confirmed the crosslinking bonds within the hydrogels, as seen by the characteristic shift in the peak. Furthermore, a low tensile modulus together with a high elongation percentage indicated that the hydrogels were easy to handle. We also showed that all hydrogels released sericin simultaneously. The poly(vinyl alcohol)/sericin hydrogels with high sericin content released more sericin, possibly due to less crosslinking of the hydrogels. When L929 cells were cultured with the hydrogel extracts, the cells were viable and could proliferate, particularly for the cells cultured wi...
International Journal of Polymeric Materials and Polymeric Biomaterials, 2017
Bacterial cellulose (BC) has been applied for wound dressing application. In this study, physical... more Bacterial cellulose (BC) has been applied for wound dressing application. In this study, physical and biological properties of the BC dressing were improved by incorporation of silk sericin (SS), polyhexamethylene biguanide (PHMB), and glycerin. The glycerin incorporation reduced dehydration rate and wound adhesion of the BC dressing in a concentration-dependent manner. PHMB, an antiseptic agent, provided antibacterial activity against gram-positive and gram-negative bacteria. Meanwhile, SS would enhance collagen and tissue formation in wounds. Finally, we confirmed that the BC dressing incorporating SS, PHMB, and glycerin was safe to be used as a medical material according to ISO 10993-6 standard.
Journal of Bioactive and Compatible Polymers, 2017
In our previous works, two techniques (freeze-drying and salt-leaching) were introduced to fabric... more In our previous works, two techniques (freeze-drying and salt-leaching) were introduced to fabricate the sericin/poly(vinyl alcohol)/glycerin scaffolds. The freeze-dried and salt-leached sericin/poly(vinyl alcohol)/glycerin scaffolds with the same composition showed distinguished physical and in vitro biological characteristics. In this study, the in vivo safety and efficacy tests of both scaffolds as dressing materials for the healing of full-thickness wounds in rat model were performed in comparison with the clinically used dressing, Allevyn®. In the safety test, the scaffolds were implanted subcutaneously, and the signs of tissue irritation including the extent of inflammatory cells, calcification, vascularization, and fatty infiltration were scored. In the efficacy test, the scaffolds were applied to the full-thickness wound (1.5 cm × 1.5 cm), and the epithelialization and collagen formation in the wound were evaluated. Both freeze-dried and salt-leached scaffolds were character...
Archives of biochemistry and biophysics, Oct 12, 2017
Silk cocoon is produced from silkworm (Bombyx mori) to protect itself from outer environment. Var... more Silk cocoon is produced from silkworm (Bombyx mori) to protect itself from outer environment. Various strains of cocoon contain different forms and amounts of flavonoids, which may affect on their antioxidant activity. Moreover, the extraction method would influence the amount of flavonoids extracted. Therefore, the objectives of this study were to identify and quantify the flavonoids in 3 strains of bivoltine Bombyx mori silk cocoon (Chul 1/1; white cocoon, Chul 3/2; greenish cocoon, and Chul 4/2; yellow cocoon) extracted by 6 different solvents including acetone, ethyl acetate, dimethyl sulfoxide (DMSO), ethanol, methanol, and purified water. The flavonoids extracted were identified and quantified by liquid chromatography-mass spectrometry (LC-MS). The antioxidant activity of flavonoids extracted was also investigated by visible spectroscopy at 517 nm. The results showed that Chul 3/2 silk cocoon contained the highest amount of flavonoids. Purified water seemed to be the best solv...
Histology and histopathology, 2016
Silk sericin-releasing (sericin/polyvinyl alcohol (PVA)/glycerin) scaffolds have been designed fo... more Silk sericin-releasing (sericin/polyvinyl alcohol (PVA)/glycerin) scaffolds have been designed for wound dressing applications using different fabrication techniques that influence scaffold antigenicity. The immunological tolerance of scaffolds depends on the balance of immunogenic and tolerogenic responses modulated by dendritic cells (DCs). An in vivo skin implantation model was used to compare the tolerogenic effect of sericin/PVA/glycerin scaffolds prepared by freeze-drying versus salt-leaching techniques, using an Allevyn® scaffold as a control. Immunohistochemical and histopathological studies were performed to evaluate tolerogenic DCs (CD206+), immunogenic DCs (CD83+), regulatory T-cells (FOXP3+ and CTLA-4), a proinflammatory cytokine (interleukin 33: IL-33), a stress marker (heat shock protein 60; HSP60), histopathological changes and related inflammatory cells. It was found that both sericin/PVA/glycerin scaffolds were tolerogenic and induced early activated Treg functions,...
Journal of biomaterials science. Polymer edition, 2017
Wound healing is a natural process of body reaction to repair itself after injury. Nonetheless, m... more Wound healing is a natural process of body reaction to repair itself after injury. Nonetheless, many internal and external factors such as aging, comorbidity, stress, smoking, alcohol drinking, infections, malnutrition, or wound environment significantly affect the quality and speed of wound healing. The unsuitable conditions may delay wound healing process and cause chronic wound or scar formation. Therefore, many researches have attempted to search for agents that can accelerate wound healing with safety and biocompatibility to human body. Widely studied wound healing agents are those derived from either natural sources including plants and animals or chemical synthesis. The natural products seem to be safer and more biocompatible to human tissue. This review paper demonstrated various kinds of the animal-derived products including chitosan, collagen, honey, anabolic steroids, silk sericin, peptides, and proteoglycan in term of mechanisms of action, advantages, and disadvantages w...
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Papers by Pornanong Aramwit