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2018

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The Effects Of Quality Assurance Rating By Independent Assessors On External Auditors’ Judgment On Evaluation Of The Internal Auditor’S Work, Patcharee Treepornchaisak Jan 2018

The Effects Of Quality Assurance Rating By Independent Assessors On External Auditors’ Judgment On Evaluation Of The Internal Auditor’S Work, Patcharee Treepornchaisak

Chulalongkorn University Theses and Dissertations (Chula ETD)

The International standard on Auditing (ISA) 610, using the work of internal audit allows the external auditors to use internal audit's work and use internal auditors as assistants. But the external auditors have to evaluate internal audit function by themselves. The self-evaluation causes uncertainty in using IAF's work and using internal auditors as assistants. The prior studies identify that the three determinants of IAF quality are objectivity, competence and work performance. This study argues that the quality assurance report (QAR) help increase external auditors' reliance decision. Moreover a paper posits that the internal control environment is also related to the …

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Physiological And Immunological Responses Of Porcine Primary Endometrial Cells To Porcine Reproductive And Respiratory Syndrome (Prrs) Virus Infection, Muttarin Lothong Jan 2018

Physiological And Immunological Responses Of Porcine Primary Endometrial Cells To Porcine Reproductive And Respiratory Syndrome (Prrs) Virus Infection, Muttarin Lothong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Porcine reproductive and respiratory syndrome virus (PRRSV) is highly limited to only cell subsets that express PRRSV receptors. Reproductive organ revealing the typical signs of PRRSV infection may be the critical site of problem syndromes. Persistent PRRSV producing re-infection via horizontal or vertical transmission could not be eradicated from herds. This research examined the possibility of porcine endometrium to be a PRRSV permissive cell and serves as the primary cause of the persistent PRRSV. Cellular and immunological in response to PRRSV relevant to viral replication, shedding and re-circulation was assessed. The different outcomes between the different genotypes (type I vs. …

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Thin Cloud Removal Using Local Minimization And Image Transformation In Hsi Color Space, Thanet Markchom Jan 2018

Thin Cloud Removal Using Local Minimization And Image Transformation In Hsi Color Space, Thanet Markchom

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the use of satellite images, clouds can be an obstacle due to their opacity property that can block the visibility of ground objects in case of thick clouds and can also be blended with the underlying details in case of thin clouds. In this research, we propose a novel method to remove thin clouds and retrieve the actual information by taking the advantage of HSI color space instead of RGB color space. The proposed method aims to estimate the cloud appearance called the scattering light, remove thin clouds from intensity channel to avoid an effect to the original color, …

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Polyamine Accumulation And Responses Of Mango Fruit To Postharvest Polyamine Application, Bussarin Wonnabussapawich Jan 2018

Polyamine Accumulation And Responses Of Mango Fruit To Postharvest Polyamine Application, Bussarin Wonnabussapawich

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mango (Mangifera indicia L.) is a popular tropical fruit which has a great value in both domestic and international markets. Mango is a climacteric fruit which ethylene production increases dramatically, thus leading to a quick ripening process and a short postharvest life. Polyamines (PAs) have been reported to be involved in fruit ripening. Changes in endogenous free polyamines accumulation were measured in two mango cultivars; ‘Nam Dok Mai No.4’ and ‘Nam Dok Mai Si Tong’. Mangoes were allowed to ripen at 25±1 ºC after harvest. It was found that ‘Nam Dok Mai No.4’ mango exhibited higher ethylene production, respiration rate, …

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Functional Characterization Of Heat Shock Proteins During Stress Response In Pacific White Shrimp Penaeus Vannamei And Brine Shrimp Artemia Franciscana, Wisarut Junprung Jan 2018

Functional Characterization Of Heat Shock Proteins During Stress Response In Pacific White Shrimp Penaeus Vannamei And Brine Shrimp Artemia Franciscana, Wisarut Junprung

Chulalongkorn University Theses and Dissertations (Chula ETD)

Acute hepatopancreatic necrosis disease (AHPND) caused by the bacterium Vibrio parahaemolyticus carrying toxin produced plasmid (VPAHPND), has led to severe mortalities in farmed penaeid shrimp throughout Asia. Our studies demonstrated that a chronic non-lethal heat shock (chronic-NLHS) could enhance resistance of the Pacific white shrimp Penaeus vannamei to VPAHPND infection. Shrimp exposed to chronic-NLHS (28 °C to 38 °C, 5 min for 7 days) had higher survival rate (>50%) than that of the control non-heated shrimp (20%) when they were challenged with VPAHPND. The qRT-PCR analysis revealed that the expression of heat shock proteins, LvHSP70 and LvHSP90, as well …

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Production And Purification Of Mannan Oligosaccharide And Its Role In Tight Junction Assembly In Epithelial Cells, Chatchai Nopvichai Jan 2018

Production And Purification Of Mannan Oligosaccharide And Its Role In Tight Junction Assembly In Epithelial Cells, Chatchai Nopvichai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mannan Oligosaccharide (MOS) is well-known as prebiotic supplement that help increasing life quality of livestocks and animals. Many reports revealed that MOS supplement can help improve intestinal morphology, enhancing growth performance, raising body weight, and increasing metabolic and stress response. MOS feeding also affected several biological processes in peripheral blood mononuclear cells in pigs and modulates expression of many immune-related genes that helps to prevent and reduce the severity of viral infection. However, the mechanism of action of MOS is remained unclear and the production, purification, identification of bioactive MOS molecular type is needed. In this study, we developed a …

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Drug Resistance Mechanism Of Ns3/4a Protease And Identification Of Potent Compounds Inhibiting Reverse Transcriptase Of Hepatitis Virus, Jirayu Kammarabutr Jan 2018

Drug Resistance Mechanism Of Ns3/4a Protease And Identification Of Potent Compounds Inhibiting Reverse Transcriptase Of Hepatitis Virus, Jirayu Kammarabutr

Chulalongkorn University Theses and Dissertations (Chula ETD)

Viral Hepatitis has become a public health concern which caused 1.34 million deaths in 2015 and 95% of sickness and untimely deaths come from chronic hepatitis B and C virus infections. The epidemic of viral hepatitis B and C affects around 325 million people worldwide and is 10 times more than the global HIV epidemic. Hepatitis C virus (HCV), which is the main cause of hepatitis C, has a high mutation rate due to the lack of proofreading activity of the RNA polymerase enzyme. One of an attractive target for anti-HCV drug design and development is the NS3/4A serine protease. …

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Effect Of Feedback-Resistant Arog Overexpression On L-Phenylalanine Production In Escherichia Coli, Maria Ulfah Jan 2018

Effect Of Feedback-Resistant Arog Overexpression On L-Phenylalanine Production In Escherichia Coli, Maria Ulfah

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-Phenylalanine (L-Phe) is one of the most important amino acids in food and pharmaceutical industries. It is widely used as a nutritional supplement and a precursor for the synthesis of food additives. The market of L-Phe has been stimulated by increasing demand for the low-calorie sweetener, aspartame. In Escherichia coli, the key enzyme which catalyzes the first committed step of aromatic amino acid biosynthesis pathway is 3-deoxy-D-arabino-heptulosonate-7- phosphate synthase (DAHP-synthase). The enzyme has 3 isoforms, AroG, AroF and AroH, which are feedback inhibited by L-Phe, L-Tyr and L-Trp, respectively. AroG, encoded by aroG, is the major isoform contributed about 80% …

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Functional Characterization Of White Spot Syndrome Virus-Responsive Mir-750 In Black Tiger Shrimp Penaeus Monodon, Nichaphat Kanoksinwuttipong Jan 2018

Functional Characterization Of White Spot Syndrome Virus-Responsive Mir-750 In Black Tiger Shrimp Penaeus Monodon, Nichaphat Kanoksinwuttipong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the RNA interference (RNAi) process, small RNAs called microRNAs (miRNAs) modulate gene expression post-transcriptionally by acting as guides to direct Argonaute (Ago)-containing RNA-induced silencing complexes (RISCs) to targeted mRNAs. The Penaeus monodon miR-750 was previously reported as the highly upregulated miRNA during white spot syndrome virus (WSSV) infection. In this study, the computational program and 2D gel electrophoresis technique were used to identify miR-750 target genes. Bioinformatic analysis suggested that the predicted target mRNAs of miR-750 were ubiquitin-conjugating enzyme E2 Q1 gene (UbcQ1), Actin1 (Act1) and Sarcoplasmic calcium-binding protein (Scp). Furthermore, the alteration of protein expression in the stomach …

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Identification And Functional Characterization Of Genes And Micrornas From Penaeus Vannamei In Response To Pathogens And Heat Stress, Pakpoom Boonchuen Jan 2018

Identification And Functional Characterization Of Genes And Micrornas From Penaeus Vannamei In Response To Pathogens And Heat Stress, Pakpoom Boonchuen

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the present day, high-throughput (HT) sequencing techniques provide in-depth data on how the transcripts are expressed and regulated and in this case shed light on how innate immunity responds to different stimuli. Acute Hepatopancreatic Necrosis Disease (AHPND) caused by Vibrio parahaemolyticusproducing Pir toxin (VPAHPND) is a current severe bacterial disease in shrimp. Suppression subtractive hybridization (SSH) was used to identify differentially expressed genes (DEGs) in hepatopancreas and hemocyte of VPAHPND-challengedPenaeus vannamei. The hemocyaninand Vago5 were found as up-regulated genes in hepatopancreas and hemocyte of VPAHPND-infectedP. vannamei, respectively. Their functions in shrimp immunity against VPAHPNDinfection were then characterized. The native …

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Anticancer Activity Of Mansonone G Derivatives Against Human Non-Small Cell Lung Cancer: Computational And Mechanistic Study, Panupong Mahalapbutr Jan 2018

Anticancer Activity Of Mansonone G Derivatives Against Human Non-Small Cell Lung Cancer: Computational And Mechanistic Study, Panupong Mahalapbutr

Chulalongkorn University Theses and Dissertations (Chula ETD)

Epidermal growth factor receptor (EGFR) and DNA topoisomerase II (Topo II) are the key molecular targets for non-small cell lung cancer (NSCLC) due to its major contribution to complex signaling cascades modulating the survival of cancer cells. In the present study, mansonone G (MG), a naturally occurring quinone-containing compound, and its semi-synthetic ether derivatives were subjected to theoretically and experimentally investigate the anticancer effects on EGFR/Topo II-mediated signaling pathways in NSCLC cell lines expressing wild-type EGFR (A549) and mutant EGFR (H1975). In vitro cytotoxicity screening results demonstrated that butoxy MG (MG3) was more susceptible to H1975 mutant cells (IC50 of …

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L-Pipecolic Acid Production In Thra Knockout Escherichia Coli, Suttilak Khuanwilai Jan 2018

L-Pipecolic Acid Production In Thra Knockout Escherichia Coli, Suttilak Khuanwilai

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-pipecolic acid (L-PA) is a non-proteinogenic amino acid, however, it is an important precursor and a key ingredient of many pharmaceutically compound syntheses such as immunosuppressants and anesthetics. The production of amino acids via fermentation of microorganisms are getting attention, one of the widely used is an engineered E. coli. L-PA production in the engineered E. coli uses L-lysine in its cell as a substrate. This research aimed to increase L-PA production by thrA knockout. The thrA encodes homoserine dehydrogenase I, the enzyme which draws the intermediate in L-lysine biosynthesis pathway to synthesize L-threonine. The group II intron insertion was …

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Effects Of Mutations Of Levansucrase From Bacillus Licheniformis Rn-01 On Levan Oligosaccharides Binding, Thassanai Sitthiyotha Jan 2018

Effects Of Mutations Of Levansucrase From Bacillus Licheniformis Rn-01 On Levan Oligosaccharides Binding, Thassanai Sitthiyotha

Chulalongkorn University Theses and Dissertations (Chula ETD)

Produced by levansucrase that uses sucrose as a substrate, levan and levan oligosaccharides (GFn) have potential applications in food and pharmaceutical industries such as prebiotics, anti-obesity and anti-tumor agents. Previous study reported that N251A and N251Y mutants of levansucrase from Bacillus licheniformis RN-01 could effectively produce short-chain oligosaccharides upto GF3, instead of long-chain levan synthesis. This study hypothesized that these mutations probably reduced GF3 binding affinity in the active site of levansucrase that contains fructosyl-Asp93 intermediate and caused GF3 to be in an unfavorable orientation for transfructosylation; therefore, levansucrase could not effectively extend GF3 to GF4. However, these mutations probably …

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Transcriptome Of Rice Oryza Sativa L. Over-Expressing Oscam1-1 Gene And Characterization Of Salt Stress-Responsive Isocitrate Lyase Gene, Worawat Yuenyong Jan 2018

Transcriptome Of Rice Oryza Sativa L. Over-Expressing Oscam1-1 Gene And Characterization Of Salt Stress-Responsive Isocitrate Lyase Gene, Worawat Yuenyong

Chulalongkorn University Theses and Dissertations (Chula ETD)

The previous study of OsCam1-1 showed that the transgenic KDML105 rice over-expressing OsCam1-1 was more tolerant to salt stress than the wild type, so to investigate the role of calmodulin encoded by OsCam1-1 in the salt-responsive mechanism, the transcriptome approach using RNA-seq technique was applied. Transcriptome profile of the transgenic KDML105 rice over-expressing OsCam1-1 under 4 hr of salt stresss (150 mM NaCl) revealed that several cell processes were affected; signaling, hormone-mediated regulation, transcription, secondary metabolism, stress responses, lipid metabolism, glycolysis, TCA cycle, glyoxylate cycle, photosynthesis, and carbohydrate metabolism. Photosynthesis rate and stomatal conductance at day 3 and 5 of …

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Functional Characterization Of Inhibitor Of Kappa B Kinase In Black Tiger Shrimp Penaeus Monodon Antiviral Signaling Pathway, Zittipong Nhnhkorn Jan 2018

Functional Characterization Of Inhibitor Of Kappa B Kinase In Black Tiger Shrimp Penaeus Monodon Antiviral Signaling Pathway, Zittipong Nhnhkorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

The IKK-NF-κB signaling cascade is one of the crucial responsive mechanisms in inflammatory and immune responses. The key kinase proteins called inhibitor of kappa B kinases (IKKs) serve as the core elements involved in cascade activation. Here, the complete open reading frames of IKK homologs including PmIKKβ, PmIKKε1 and PmIKKε2, from the black tiger shrimp Penaeus monodon were identified and characterized for their functions in shrimp antiviral responses. The PmIKK transcripts were widely expressed in various examined tissues and the PmIKKε protein was detected in all three types of shrimp hemocytes. Only the PmIKKε1 and PmIKKε2 were responsive to white …

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Mutation Identification And Functional Analysis Of Mutant Dax-1 Proteins Found In Thai Patients With X-Linked Adrenal Hypoplasia Congenita, Chanisara Suthiworachai Jan 2018

Mutation Identification And Functional Analysis Of Mutant Dax-1 Proteins Found In Thai Patients With X-Linked Adrenal Hypoplasia Congenita, Chanisara Suthiworachai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mutations in the DAX-1 gene result in X-linked adrenal hypoplasia congenita (X-linked AHC), a rare congenital disorder of adrenal insufficiency with defects in adrenal gland development and steroid biosynthesis. Male patients usually develop severe adrenal insufficiency in early infancy or childhood. In some cases, hypogonadotropic hypogonadonism (HH) is presented in puberty. DAX-1 gene product, DAX-1 protein, acts as a transcriptional repressor of genes in the steroidogenic pathway by interacting with, and repressing the steroidogenic factor 1 (SF-1) protein. In contrast, the SF-1 protein transactivates the steroidogenic acute regulatory (StAR) protein that functions in the steroid biosynthetic pathway. The aim of …

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Effects Of Habitat Enhancement On Bird Diversity In Kaeng Khoi District, Saraburi Province, Dijan Sunar Rukmi Jan 2018

Effects Of Habitat Enhancement On Bird Diversity In Kaeng Khoi District, Saraburi Province, Dijan Sunar Rukmi

Chulalongkorn University Theses and Dissertations (Chula ETD)

Various techniques of habitat enhancement have been used to increase the habitat quality, consequently enriching biodiversity and maintaining ecosystem services. This study aims to assess the effects of habitat enhancement on bird diversity, guild composition and bird usage pattern by conducting bird censuses and observations as well as arthropod samplings in the landscape-scale (LS) experiment plots and in the teak reforestation (TR) enhanced with sunflower and sunn hemp species over dry and wet seasons of 2015-2016. Sunflower treatment attracted more bird species (LS: 28, TR: 19) than sunn hemp treatment (LS: 25, TR: 15), but bird occurrence was varied based …

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Taxonomy And Systematics Of Earthworm Genus Pontodrilus Perrier, 1874 In Thailand, Teerapong Seesamut Jan 2018

Taxonomy And Systematics Of Earthworm Genus Pontodrilus Perrier, 1874 In Thailand, Teerapong Seesamut

Chulalongkorn University Theses and Dissertations (Chula ETD)

A taxonomic study of the littoral earthworm genus Pontodrilus Perrier, 1874 was critically conducted based on material collected from marine sandy coasts along the east and west sides of the Thai-Malay Peninsula (Thailand and Malaysia) and selected localities in Japan. Comparative material from other parts of Southeast Asia, including Myanmar, Vietnam, Malaysia, Singapore and Indonesia, were also collected. Morphological examination identified almost all of the specimens as Pontodrilus litoralis, but as two morphotypes with some character differences in the diverticulum between them. A combined morphological and molecular phylogenetic analyses supported one of these morphotypes as a new species, P. longissimus. …

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Suppressive Effect Of Crepidatin On Stemness Of Lung Cancer Cells, Narumol Bhummaphan Jan 2018

Suppressive Effect Of Crepidatin On Stemness Of Lung Cancer Cells, Narumol Bhummaphan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cancer stem cells (CSCs) have been perceived as rare populations driving cancer progression, metastasis, and drug resistance in leading cancers. The discovery of new compounds that attenuates CSCs’ properties is crucial for enabling advances in novel therapeutics to limit recurrence. We have reported the CSC-suppressing activity of chrysotoxine and crepidatin, two bibenzyl compounds isolated from Dendrobium pulchellum. Both chrysotoxine and crepidatin displayed suppression in CSC-like phenotypes, as determined in CSC-rich populations and primary CSCs in 3D culture and extreme limiting dilution assay. Individual treatment of chrysotoxine and crepidatin also affected the expression of CSC markers and associated proteins concomitantly decreased …

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The Role Of Cytokine Response Signatures In The Pathogenesis Of Leptospirosis Associated Acute Kidney Injury, Nattachai Srisawat Jan 2018

The Role Of Cytokine Response Signatures In The Pathogenesis Of Leptospirosis Associated Acute Kidney Injury, Nattachai Srisawat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Acute Kidney Injury (AKI) is one of the most serious complications of leptospirosis, an important zoonosis in the tropics. Host pathogen interaction is one of the potential key factor in development of leptospirosis associated AKI. In this multicenter study, we aimed to study the association of cytokines, leptospiral burden, and anti-leptospira antibody and AKI in leptospirosis. Method: In the first cohort, patients who presented with clinical suspiciousness of leptospirosis were prospectively enrolled in 9 centers from August 2012 to November 2014. In the second cohort, we prospectively recruited patients from 15 centers from February 2016 to July 2017. The …

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Molecular Epidemiology And Characterization Of Rotavirus Group A, Group C And Porcine Epidemic Diarrhea Virus In Pigs With Gastroenteritis Among The Commercial Swine Farms In Thailand, 2011-2016, Supansa Tuanthap Jan 2018

Molecular Epidemiology And Characterization Of Rotavirus Group A, Group C And Porcine Epidemic Diarrhea Virus In Pigs With Gastroenteritis Among The Commercial Swine Farms In Thailand, 2011-2016, Supansa Tuanthap

Chulalongkorn University Theses and Dissertations (Chula ETD)

The most frequent viruses associated with pig gastroenteritis have been previously reported as porcine epidemic diarrhea virus (PEDV) and rotavirus (RV). Rotavirus is an important cause of diarrhea in piglets and pigs worldwide, and group A (RVA) and group C (RVC) are mostly affected. In Thailand, studies on RVA and PEDV have been reported periodically, whereas information on RVC is still limited. In this study, 769 samples (fecal and intestinal content) from pigs with diarrhea were collected from pig herds located in difference provinces throughout Thailand between 2011 and 2016. The specimens were tested using virus-specific RT-PCR to detect the …

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Establishment Of An In Vitro System To Screen For Substances To Improve Osteogenesis Imperfecta Osteoblasts’ Functions, Wandee Udomchaiprasertkul Jan 2018

Establishment Of An In Vitro System To Screen For Substances To Improve Osteogenesis Imperfecta Osteoblasts’ Functions, Wandee Udomchaiprasertkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Osteogenesis imperfecta (OI) is a heritable bone disorder caused mainly by dominant mutations in genes encoding collagen-related proteins which are COL1A1 and COL1A2. Genotype-phenotype correlation has some discrepancies which lead to the difficult prediction of the clinical outcome of OI patients. We identified a child with dentinogenesis imperfecta (DI) and OI who was homozygous for c.1009G>A (p.G337S) mutation in COL1A2. Her parents were heterozygous for the mutation and had only DI. This family provides the opportunity to explore the biochemical changes which are different between the homozygous with DI and OI and the heterozygous with DI only. Methods: …

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Immunity To Pertussis Vaccination, Nasamon Wanlapakorn Jan 2018

Immunity To Pertussis Vaccination, Nasamon Wanlapakorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Thailand has implemented universal whole cell pertussis vaccination in children for more than 35 years; nevertheless, the numbers of reported pertussis cases are still on the rise, especially among infants below one year who bear the greatest risk of severe complications. Several countries have implemented a pertussis booster during adolescence. However, data on the appropriate age groups targeted for a booster in the Thai population is limited. The increase in pertussis incidence among Thai infants warrants the need to further investigate the pre-existing maternal antibody against Bordetella pertussis (B. pertussis) antigens and the potential benefit of Tetanus toxoid-reduced dose of …

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Effects Of 4,5,4'-Trihydroxy-3,3'-Dimethoxybibenzyl From Dendrobium Ellipsophyllum On Induction Of Apoptosis And Inhibition Of Cancer Stem-Like Cells In Human Lung Cancer H460 Cells, Anirut Hlosrichok Jan 2018

Effects Of 4,5,4'-Trihydroxy-3,3'-Dimethoxybibenzyl From Dendrobium Ellipsophyllum On Induction Of Apoptosis And Inhibition Of Cancer Stem-Like Cells In Human Lung Cancer H460 Cells, Anirut Hlosrichok

Chulalongkorn University Theses and Dissertations (Chula ETD)

Failure of current chemotherapeutic drugs leads to the recurrence of tumors and increased mortality in lung cancer patients. This study investigated 4,5,4'-trihydroxy-3,3'-dimethoxybibenzyl (TDB), a bibenzyl extracted from Dendrobium ellipsophyllum Tang and Wang as a novel anticancer agent for lung cancer. Selective anticancer activity of TDB against human lung cancer cells was demonstrated with a high half maximal inhibitory concentration (IC50) approximately > 300 µM in dermal papilla cells, while IC50 in human lung cancer H460 cells was approximately 100 ± 5.18 µM. Flow cytometry confirmed that TDB (50 µM) treatment for 24 h, caused significant early and late apoptosis but not …

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Effect Of Major Triterpenoids Of Centella Asiatica On Neurite Outgrowth In Neuro-2a Cells, Nonthaneth Nalinratana Jan 2018

Effect Of Major Triterpenoids Of Centella Asiatica On Neurite Outgrowth In Neuro-2a Cells, Nonthaneth Nalinratana

Chulalongkorn University Theses and Dissertations (Chula ETD)

Centella asiatica has been reported to demonstrate neuroprotection and memory improvement in various animal models. Triterpenoid glycosides, madecassoside (MS), asiaticoside (AS), and their aglycones, madecassic acid (MA) and asiatic acid (AA) are considered as major neuroactive constituents in C. asiatica. In this study we aimed to compared MS, AS, MA and AA for their neurite outgrowth activities and mechanisms in Neuro-2a cells. Immunofluorescent staining against ßIII-tubulin showed that MS and AS significantly increased the percentage of neurite-bearing cells and neurite length with higher potency than MA and AA. Our mechanistic studies revealed the differences in signal activation between glycosides and …

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A Study On The In Vitro Stability And Metabolism Of Curcumin Diethyl Disuccinate In Plasma, Pahweenvaj Ratnatilaka Na Bhuket Jan 2018

A Study On The In Vitro Stability And Metabolism Of Curcumin Diethyl Disuccinate In Plasma, Pahweenvaj Ratnatilaka Na Bhuket

Chulalongkorn University Theses and Dissertations (Chula ETD)

Stability in aqueous media such as buffers and plasma are the one of important properties of drug candidates. Curcumin diethyl disuccinate (CDD), an ester prodrug of curcumin, has been developed to improve the chemical stability of curcumin. In this study, the in vitro stability of CDD in HCl buffer (pH 1.2), acetate buffer (pH 4.5), phosphate buffer (pH 6.8, 7.4 and 8.0) and in vitro metabolism of CDD in rat, dog and human plasma were investigated at 4, 25 and 37 °C. HPLC and nonlinear regression analyses showed that the degradation of CDD in buffers was temperature-dependent and followed pseudo-1st …

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Optimization Of Protein Hydrolysate Preparation From Split Gill Mushroom Schizophyllum Commune, Aunchalee Wongaem Jan 2018

Optimization Of Protein Hydrolysate Preparation From Split Gill Mushroom Schizophyllum Commune, Aunchalee Wongaem

Chulalongkorn University Theses and Dissertations (Chula ETD)

The optimum conditions for hydrolysate production from split gill mushroom protein using the microbial protease, Alcalase were investigated. The study was conducted using central composite design and response surface methodology. Three independent factors: hydrolysis temperature (45, 50, and 55 °C); hydrolysis time (60, 120, and 180 min); and enzyme to substrate ratio (2%, 4%, and 6% w/v) were varied, while the pH was fixed at pH 8. These three factors had a significant effect on the DH and ABTS radical-scavenging activity (p < 0.05). The optimum conditions obtained from experiments were: enzyme to substrate ratio 2%; hydrolysis time 161.4 min; and temperature 55 °C. The coefficient of determination (R2) of total protein and the IC50 value for ABTS radical-scavenging activity were 0.972 and 0.205 µg/mL, respectively, and the DH value was 50.882%. The hydrolysate was fractionated by molecular weight (MW) cut-off membranes (10, 5, 3, and 0.65 kDa). The < 0.65 kDa fraction had the highest radical scavenging ability (IC50 = 0.026 ± 0.004 µg/mL). The MW < 0.65 kDa fraction was separated by reversed-phase HPLC to yield four subfractions (F1–5). The F4 subfraction showed the highest maximum ABTS radical-scavenging activity and was selected for further analysis by quadrupole-time-of-flight-electron spin induction–mass spectrometry-based. Five antioxidant peptides were identified. In addition, the MW< 0.65 kDa fraction protected against oxidation-induced DNA damage in pBR322, pKS, and pUC19 plasmids. Furthermore, the MW < 0.65 kDa fraction, exhibited cellular antioxidant activity in a human intestinal cancer cell line (HT-29), which was dependent on the peptide concentration. These results suggested that split gill mushroom protein hydrolysate is a good source of bioactive peptides and has potential as a natural antioxidant in food production and cosmetic products.

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Reaction Mechanisms Of Substrate And Inhibitor With Ns2b/Ns3 Serine Protease Of Zika Virus By Mm And Qm/Mm Simulations, Bodee Nutho Jan 2018

Reaction Mechanisms Of Substrate And Inhibitor With Ns2b/Ns3 Serine Protease Of Zika Virus By Mm And Qm/Mm Simulations, Bodee Nutho

Chulalongkorn University Theses and Dissertations (Chula ETD)

Zika virus (ZIKV) infection has become a public health concern worldwide. The recent epidemiological data have revealed a possible association of ZIKV infection with neurological manifestations in both newborn children and adults. Currently, there is no anti-ZIKV drug or vaccine available for preventing or controlling ZIKV infection. An attractive drug target for ZIKV treatment is NS2B/NS3 serine protease that plays a crucial role to cleave the peptide bond during the viral replication process. Initially, the ZIKV NS2B/NS3 serine protease in complex with four peptide substrates were studied to investigate the binding recognition and protein-substrate interactions using conventional molecular dynamics (MD) …

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การประยุกต์ใช้เทคนิคการเรียนรู้เชิงลึกในการฝังคำเพื่อสร้างแบบจำลองสำหรับทำนายผลการวินิจฉัยโรคจากบันทึกทางการแพทย์ของแผนกออร์โธปิดิกส์, ธนากร รัตนจริยา Jan 2018

การประยุกต์ใช้เทคนิคการเรียนรู้เชิงลึกในการฝังคำเพื่อสร้างแบบจำลองสำหรับทำนายผลการวินิจฉัยโรคจากบันทึกทางการแพทย์ของแผนกออร์โธปิดิกส์, ธนากร รัตนจริยา

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้จะนำเสนอวิธีการฝังคำในการเรียนรู้เชิงลึกเพื่อสร้างแบบจำลองสำหรับทำนายผลการวินิจฉัยโรค ซึ่งปัจจัยสำคัญที่ทำให้ผลการวินิจฉัยโรคของแพทย์ผิดพลาดคือประสบการณ์ของแพทย์ที่ไม่เพียงพอ โดยการวินิจฉัยโรคที่ผิดพลาดนั้น นอกจากจะนำไปสู่การรักษาที่ผิดพลาดแล้ว ยังทำให้ผู้ป่วยเสียทั้งเงินและเวลา ดังนั้นเพื่อแก้ไขปัญหาการวินิจฉัยที่ผิดพลาด งานวิจัยนี้จึงนำเสนอวิธีการประยุกต์ใช้การเรียนรู้เชิงลึกกับการฝังคำ เพื่อทำนายผลการวินิจฉัยโรคจากระบบเวชระเบียน โดยจะสร้างแบบจำลองจากการใช้ข้อมูลในบันทึกของแพทย์ ซึ่งข้อมูลจะถูกนำไปวิเคราะห์ผ่านแบบจำลอง เพื่อทำนายผลการวินิจฉัยโรคที่มีความน่าจะเป็นออกมา เรียงตามลำดับความเชื่อมั่น และสุดท้ายจะใช้อัตราผลบวกจริง อัตราผลบวกเท็จ และค่าความแม่นยำมาเป็นตัววัดประสิทธิภาพของแบบจำลองที่ได้ ซึ่งพบว่าค่าความแม่นยำของแบบจำลองในงานวิจัยนี้มีค่าเท่ากับ 99.95% และอัตราผลบวกจริงมีค่าเท่ากับ 86.64% ด้วยการทำนายผลลัพธ์อันดับแรกเพียงอันดับเดียว

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ระบบสังเคราะห์เสียงร้องเพลงภาษาไทยโดยใช้แบบจำลองฮิดเดนมาร์คอฟ, ลัทธพล จีระประดิษฐ Jan 2018

ระบบสังเคราะห์เสียงร้องเพลงภาษาไทยโดยใช้แบบจำลองฮิดเดนมาร์คอฟ, ลัทธพล จีระประดิษฐ

Chulalongkorn University Theses and Dissertations (Chula ETD)

การร้องเพลงในแต่ละภาษานั้นมีเอกลักษณ์เฉพาะตัวบางอย่างซึ่งส่งผลให้การพัฒนาความเป็นธรรมชาติของเสียงร้องเพลงสังเคราะห์ในแต่ละภาษานั้นมีความท้าทายแตกต่างกัน เสียงวรรณยุกต์เป็นส่วนที่มีผลมากกับการสื่อสารในภาษาที่มีเสียงวรรณยุกต์ แต่ระบบสังเคราะห์เสียงร้องเพลงในปัจจุบันไม่ได้คำนึงถึงเสียงวรรณยุกต์ นอกจากนี้เมลิสมาเป็นอีกสถานการณ์หนึ่งที่พบได้บ่อยครั้งในการร้องเพลงป็อปไทยซึ่งต้องมีการจัดการเพื่อจำลองการร้องเมลิสมา เป้าหมายของวิทยานิพนธ์นี้จึงมุ่งเน้นที่การปรับระบบสังเคราะห์เสียงร้องเพลงให้รองรับการจำลองเสียงในสถานการณ์เมลิสมาและผลกระทบของเสียงวรรณยุกต์ งานวิทยานิพนธ์นี้เสนอ 1) ปัจจัยบริบทที่ใช้ในระบบสังเคราะห์เสียงร้องเพลงสำหรับภาษาที่วรรณยุกต์มีผลต่อเสียงร้องเพลงและคำนึงถึงเมลิสมา 2) วิธีการทำสำเนารูปเขียน จากการประเมินผลพบว่า วิธีการทำสำเนารูปเขียนที่เสนอทั้งสองแบบนั้นส่งผลให้ระบบสังเคราะห์เสียงร้องเพลงรองรับเมลิสมา โดยวิธีการทำสำเนารูปเขียนที่คำนึงถึงสระเสียงสั้น-ยาวและตัวสะกดนั้นมีรูปคลื่นของเสียงร้องเพลงสังเคราะห์ใกล้เคียงกับรูปคลื่นของเสียงร้องเพลงจริงมากกว่า รวมถึงมีความเป็นธรรมชาติมากกว่าโดยใช้มาตรวัดเอ็มโอเอส อีกทั้งเมื่อมีปัจจัยบริบทที่เกี่ยวข้องกับเสียงวรรณยุกต์ เค้ารูปของความถี่มูลฐานที่สังเคราะห์ได้นั้นมีความใกล้เคียงเสียงร้องเพลงจริงมากกว่าในระบบที่ไม่มีปัจจัยบริบทที่เกี่ยวข้องกับเสียงวรรณยุกต์ และมีความเป็นธรรมชาติมากขึ้นโดยใช้มาตรวัดเอ็มโอเอส นอกจากนี้เพื่อเพิ่มความเป็นธรรมชาติให้เสียงร้องเพลงสังเคราะห์จึงมีการทดลองเกี่ยวกับจำนวนสถานะของแบบจำลองเสียงพบว่า เมื่อจำนวนสถานะเพิ่มขึ้น ความเป็นธรรมชาติของเสียงร้องเพลงสังเคราะห์ก็มากขึ้น แต่เมื่อถึงจุดหนึ่งเสียงร้องเพลงสังเคราะห์ที่ได้จะมีความเป็นธรรมชาติลดลง

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