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Chulalongkorn University Theses and Dissertations (Chula ETD)

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The Effect Of Histone Methylation In Trained Innate Immunity Of Cord Blood Monocytes In Newborn Infants Of Chronic Hbv-Infected Mothers, Pennapa Plypongsa Jan 2022

The Effect Of Histone Methylation In Trained Innate Immunity Of Cord Blood Monocytes In Newborn Infants Of Chronic Hbv-Infected Mothers, Pennapa Plypongsa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Newborns contract Hepatitis B virus (HBV) through exposure in utero from mothers who are infected with HBV. In newborn infant from chronic HBV-infected mothers, the immune system displays innate immune cell maturation and enhances immune response upon restimulation with unrelated pathogens such as bacteria. This pattern is called “trained immunity” or “innate immune memory”. Trained immunity is regulated by epigenetic programming, especially histone modification. To date, there is not report on the epigenetics to regulate trained immunity in HBV. Therefore, this study investigated the cytokines levels and expression levels of histone modification enzyme genes in HBV-exposed cord blood monocytes. Moreover, …


Effect Of Candida Glabrata Β-Glucans On Immunosuppressive Properties Of Dendritic Cells, Phawida Tummamunkong Jan 2022

Effect Of Candida Glabrata Β-Glucans On Immunosuppressive Properties Of Dendritic Cells, Phawida Tummamunkong

Chulalongkorn University Theses and Dissertations (Chula ETD)

β-glucan is a polysaccharide and consists of the backbone of β-(1, 3)-glucan and/or β-(1, 6)-glucan structures. β-glucans are extracted from the cell wall of Candida sp, including Candida glabrata. Interestingly, the biological activity of Candida β-glucan has been represented as a stimulator in the mechanism of immune responses. Dendritic cells are powerful antigen-presenting cells that play a significant role in both innate and adaptive immunity. In the present study, we evaluated the effect of C. glabrata β-glucans on dendritic cell (DC) immunologic responses. Firstly, bone marrow-derived DCs (BMDCs) were induced with C. glabrata β-glucans in a dose-dependent manner. The expression …


Generation Of Tolerogenic Dendritic Cells From Fcgr2b Deficient Lupus-Prone Mice For The Model Of Sle Therapy, Phuriwat Khiewkamrop Jan 2022

Generation Of Tolerogenic Dendritic Cells From Fcgr2b Deficient Lupus-Prone Mice For The Model Of Sle Therapy, Phuriwat Khiewkamrop

Chulalongkorn University Theses and Dissertations (Chula ETD)

Tolerogenic dendritic cells (tolDCs) are DCs with an immunoregulatory function, which can induce regulatory T cells (Tregs) and suppress the immune response. Currently, tolDCs-based treatment has become a promising therapeutic approach for organ transplantation and autoimmune disease. FcgRIIB is an inhibitory receptor widely expressed in B cells, myeloid cells, and DCs. The ablation of FcgRIIB in the murine model shows a spontaneous development of a lupus-like disease and might affect other immune cell regulation. There was limited information on tolDC induction in FcgRIIB defective mice. Thus, in this study, we studied the generation of tolDCs from the bone marrow-derived dendritic …


Macrophage Depletion Enhances Gut Dysbiosis And Severity In Sepsis Mouse Model, Pratsanee Hiengrach Jan 2022

Macrophage Depletion Enhances Gut Dysbiosis And Severity In Sepsis Mouse Model, Pratsanee Hiengrach

Chulalongkorn University Theses and Dissertations (Chula ETD)

Macrophage is vital players in the responsiveness of the innate immune system against injury or infection. Although macrophage depletion is well-known for some emerging therapies, such as osteoporosis, osteopenia, and decreasing tumor-associated macrophages in melanoma, dysfunction of macrophages leads to an inability of an appropriate immune response and implicated in various disease processes, especially intestinal macrophages that play a key role in the gut immune system and the regulation of gastrointestinal physiology. To obtain an understanding of the role of sepsis-associated macrophages, clodronate was used for the dysfunction of mouse macrophages with and without cecal ligation and puncture (CLP) sepsis. …


Epigenetic Regulation In Trained And Tolerized Macrophages, Salisa Benjaskulluecha Jan 2022

Epigenetic Regulation In Trained And Tolerized Macrophages, Salisa Benjaskulluecha

Chulalongkorn University Theses and Dissertations (Chula ETD)

Innate immune memory is the phenomenon that can either enhance (trained) or suppress (tolerized) immune response by innate immune cells during the second encounter of the stimuli such as pathogens. Previous studies reported that epigenetic regulations critically regulate both types of innate immune memory. However, a complete understanding of the underlying mechanisms is still lacking. In this study, we performed a screening of an epigenetics compound library to identify inhibitors that affect ß-glucan (BG)-trained or LPS-tolerized macrophages. Among 181 compounds tested, various inhibitors targeting Aurora kinase, histone methyltransferase PRMT and EZH2, histone demethylase LSD1 and JMJD2, histone deacetylase 6 and …


Effects Of Different Serum Supplements On Piggybac Cd19 Chimeric Antigen Receptor T Cells, Mulita Sanyanusin Jan 2022

Effects Of Different Serum Supplements On Piggybac Cd19 Chimeric Antigen Receptor T Cells, Mulita Sanyanusin

Chulalongkorn University Theses and Dissertations (Chula ETD)

Chimeric Antigen Receptor (CAR) T cell is a novel therapy for relapse and refractory hematologic malignancy. Characteristics of CAR T cells is associated with clinical efficacy and toxicity. Type of serum supplements used during cultivation affect the immunophenotype and function of viral-based CAR T cells. This study explores the effect of serum supplements on non-viral piggyBac transposon CAR T cell production. PiggyBac CD19 CAR T cells were expanded in cultured conditions containing either fetal bovine serum, human AB serum, human platelet lysate or xeno-free serum replacement. Then, the effect of different serum supplements on cell expansion, transfection efficiency, immunophenotypes and …


Study Of Thermodynamic Binding Between Ader And Ades In Two-Component Antibiotic Sensor Of Antibiotic Resistant Strains Of Acinetobacter Baumannii, Konrawee Thananon Jan 2022

Study Of Thermodynamic Binding Between Ader And Ades In Two-Component Antibiotic Sensor Of Antibiotic Resistant Strains Of Acinetobacter Baumannii, Konrawee Thananon

Chulalongkorn University Theses and Dissertations (Chula ETD)

The proteins AdeR (response regulator) and AdeS (histidine kinase sensor) play a crucial role in regulating the efflux pump, which is responsible for removing antibiotics from bacterial cells. This regulation occurs through a two-component regulatory system (TCS) involving autophosphorylation. Upon receiving external signals, AdeS undergoes autophosphorylation, leading to the activation of AdeR, which in turn initiates the expression of target genes related to the efflux pump. In this study, both enzymes from the reference strain of Acinetobacter baumannii (ATCC19606) and antibiotic resistant strains (H1074 and G560) were cloned and expressed in E. coli. The enzymes were purified using an immobilized …


The Inhibitory Effect Of Combined Human Cathelicidin With Antibiotics On Antibiotic-Resistant Cutibacterium Acnes, Rakwaree Sriharat Jan 2022

The Inhibitory Effect Of Combined Human Cathelicidin With Antibiotics On Antibiotic-Resistant Cutibacterium Acnes, Rakwaree Sriharat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cutibacterium acnes is one of the major factors involved in the pathogenesis of acne vulgaris which sometimes develops antibiotic resistance particularly clindamycin- and doxycycline-resistant C. acnes. In this study, human cathelicidin (LL-37) which is a type of human antimicrobial peptide against a wide range of microorganisms was used. We investigated the antimicrobial activity of LL-37 on C. acnes isolated from patients with acne at the King Chulalongkorn Hospital using broth microdilution. Moreover, the synergistic effects of LL-37 with clindamycin and doxycycline were investigated using checkerboard microdilution, and time-killing assays. The cytotoxicity of LL-37 was also evaluated by MTT assay. The …


Development Of A Human Viable Heavy Chain Antibody Against The Alpha Folate Receptor As A Molecule For Targeted Application By Phage Display Technology, Nattihda Parakasikron Jan 2021

Development Of A Human Viable Heavy Chain Antibody Against The Alpha Folate Receptor As A Molecule For Targeted Application By Phage Display Technology, Nattihda Parakasikron

Chulalongkorn University Theses and Dissertations (Chula ETD)

Alpha folate receptor (FRα) is currently under investigation as a target for the treatment of patients with non-small-cell lung cancer (NSCLC), since it is highly expressed in tumor cells but is largely absent in normal tissue. In this study, a novel human variable domain of a heavy-chain (VH) antibody fragment specific to FRα was enriched and selected by phage bio-planning. The positive phage clone (3A102 VH) is specifically bound to FRα and also cross-reacted with FRβ, as tested by ELISA. Clone 3A102 VH was then successfully expressed as a soluble protein in an E. coli shuffle strain. The obtained soluble …


Designing An Extracorporeal Plasma Filtration Column With Specific Binding To Dengue Virions, Sasiwimon Thonghong Jan 2021

Designing An Extracorporeal Plasma Filtration Column With Specific Binding To Dengue Virions, Sasiwimon Thonghong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Dengue infection is one of the major public health concerns and no specific treatment is currently available. An extracorporeal system is one of the alternative treatment in severe dengue patients with impending shock. However, the commercial immunoadsorption devices were size-exclusive, non-selective designed for multipurpose thus not specific for dengue syndrome. This study focuses on establishing the flavivirus-specific (4G2) antibody entrapped into the alginate bead. Results showed that the viral titer reduced more than 90 % after 3 h running on a simulated circuit quantified by reverse transcription qPCR and plaque titration assay. The experiments were repeated with two biological replicates …


Endotoxemia From Nsaids-Induced Gut-Leakage Enhanced Lupus Characteristics In Fc Gamma Receptor Iib Deficient Lupus Mice, Thansita Bhunyakarnjanarat Jan 2021

Endotoxemia From Nsaids-Induced Gut-Leakage Enhanced Lupus Characteristics In Fc Gamma Receptor Iib Deficient Lupus Mice, Thansita Bhunyakarnjanarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

High dose of non-steroidal anti-inflammatory drugs (NSAIDs), the common analgesia, might induce lupus activity through NSAIDs-induced gastrointestinal permeability defect (gut leakage) that causes endotoxemia. Indomethacin (25 mg/day) was orally administered for 7 days in 24-week-old Fc gamma receptor IIb deficient (FcgRIIb-/-) mice, an asymptomatic lupus model, and age-matched wild-type (WT) mice. The severity of indomethacin-induced enteropathy in FcgRIIb-/- mice was higher than WT mice as demonstrated by intestinal injury (histology, immune-deposition and intestinal cytokines), gut leakage (FITC-dextran assay and endotoxemia) and serum cytokines. In addition, higher responses against endotoxemia in indomethacin-administered FcgRIIb-/- mice was also supported by the prominent responses …


Impact Of Bacterial Dna In Severity Of Sepsis, Warerat Kaewduangduen Jan 2021

Impact Of Bacterial Dna In Severity Of Sepsis, Warerat Kaewduangduen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Bacterial sepsis can be caused by intestinal damage, leading to the passage of viable bacteria and their components into the circulatory system. Bacterial-free DNA in the blood during sepsis can be derived from bacterial death and intestinal translocation of free DNA in the gut contents. The presence of bacterial DNA in combination with lipopolysaccharide (LPS) can lead to more serious outcomes of sepsis. To explore the impact of bacterial-free DNA in sepsis, animal and macrophage experiments were performed. Firstly, the appearance of bacterial-free DNA and bacteriome in the blood was presented in mice with cecal ligation and puncture sepsis. Secondly, …


The Role Of Neutrophils Against Pythium Insidiosum, Apichaya Sriwarom Jan 2021

The Role Of Neutrophils Against Pythium Insidiosum, Apichaya Sriwarom

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pythium insidiosum (P. insidiosum) is an oomycetes fungus-like microorganism causing pythiosis infection in humans. The zoospores (infective stage) of this pathogen contaminate aquatic environments such as moist soil and swampy area, which is a natural habitiat. Humans are infected with P. insidiosum via cutaneous route which is the main entry of the zoospores. Recent studies have shown that patients with pythiosis shows high morbidity and mortality rates particularly those with hematologic diseases. As neutrophils are the first line of immune defense during fungal infections, this study therefore investigated the activity of neutrophils in response to P. insidiosum. The neutrophil killing …


Mechanisms Of Colistin Resistance And The Antimicrobial Effects Of Antibiotic And Adjuvant Combination On Colistin-Resistant Klebsiella Pneumoniae, Aye Mya Sithu Shein Jan 2021

Mechanisms Of Colistin Resistance And The Antimicrobial Effects Of Antibiotic And Adjuvant Combination On Colistin-Resistant Klebsiella Pneumoniae, Aye Mya Sithu Shein

Chulalongkorn University Theses and Dissertations (Chula ETD)

The prevalence of colistin-resistant Klebsiella pneumoniae (ColRkp) has progressively increased globally. The purposes of this study were to characterize the molecular mechanisms responsible for colistin resistance among ColRkp clinical isolates in Thailand, to determine the expression levels of virulence factors associated with ColRkp clinical isolates, and to evaluate in vitro and in vivo synergistic activities of novel combination of antibiotic and adjuvant against ColRkp clinical isolates. A total of 165 carbapenem-resistant K. pneumoniae clinical isolates were obtained from King Chulalongkorn Memorial Hospital between 2016 and 2021. We discovered a rising trend of ColRkp displaying extensively drug-resistant (XDR) and pandrug-resistant (PDR) …


A Comparative Study Of Gut Microbiota In The Healthy Elderly And The Elderly With Colorectal Cancer, Nutta Iadsee Jan 2021

A Comparative Study Of Gut Microbiota In The Healthy Elderly And The Elderly With Colorectal Cancer, Nutta Iadsee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Colorectal cancer is one of the third most common cancer worldwide. Dysbiosis of the human gut microbiota has been linked to sporadic colorectal cancer (CRC). This study aimed to compare the gut microbiota profile of a total of 80 Thai volunteers, who were above 50 years old, among 25 CRC patients, 33 adenoma patients, and 22 healthy controls (HC). The 16S rRNA sequencing was utilized to characterize the gut microbiome in both mucosal tissue and stool samples. Moreover, absolute quantitative PCR (qPCR) assay was conducted to quantify six CRC-associated bacteria including Fusobacterium nucleatum (FN), Parvimonas micra (PM), colibactin positive strains …


Comparative Response Of Dendritic Cells To Pathogenic And Non-Pathogenic Leptospira Spp., Pratomporn Krangvichian Jan 2021

Comparative Response Of Dendritic Cells To Pathogenic And Non-Pathogenic Leptospira Spp., Pratomporn Krangvichian

Chulalongkorn University Theses and Dissertations (Chula ETD)

Leptospirosis is a zoonotic disease caused by pathogenic Leptospira species, which consist of three groups and contain 4 subclades: pathogenic strains (P1), intermediate strains (P2), and non-pathogenic strains (S1 and S2). Infection of pathogenic leptospires occurs through contact with contaminated environments. Then, leptospires present in the bloodstream disseminate to target organs. Nowadays, the knowledge of the immune response to pathogenic and non-pathogenic leptospires during early infection is still limited. Due to the limitation of a susceptible host, immunological reagents for hamsters and strains of mice are limited and not available. Dendritic cells are the first cells to encounter leptospires found …


The Effect Of Xylitol And Erythritol In The Presence Of Sucrose On Single And Mixed-Species Biofilm Of Early Colonizer And Cariogenic Streptococci, Panadda Yuapibanrak Jan 2021

The Effect Of Xylitol And Erythritol In The Presence Of Sucrose On Single And Mixed-Species Biofilm Of Early Colonizer And Cariogenic Streptococci, Panadda Yuapibanrak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Dental caries is caused by multiple factors. An essential factor is sucrose. Dental caries is the result of an imbalance between early colonizers and cariogenic bacteria in biofilms. Sugar alcohols, xylitol and erythritol, become more popular because they do not cause cavities and are also effective at preventing caries. In everyday life, however, sucrose consumption is unavoidable. Thus, the aim of this study was to investigate the effect of xylitol and erythritol in the presence of sucrose on single- and mixed-species biofilm of early colonizers and cariogenic bacteria. Bacteria were cultured in broth containing 1% sucrose compared to broth containing …


The Synergistic Activity Of Antibiotic Combinations Against Colistin-Resistant Acinetobacter Baumannii Clinical Isolates And Its Mechanisms Related To Colistin Resistance, Sukrit Srisakul Jan 2021

The Synergistic Activity Of Antibiotic Combinations Against Colistin-Resistant Acinetobacter Baumannii Clinical Isolates And Its Mechanisms Related To Colistin Resistance, Sukrit Srisakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

The increasing development of colistin resistance in Acinetobacter baumannii clinical isolates is a global concern. Due to the limitation of effective antibiotics, the antibiotic combination therapies are the alternative choices. Here, we investigated the prevalence of colistin resistant A. baumannii (CoR-AB) clinical isolates and their resistance mechanisms, and examined the in vitro synergistic activities of the antibiotic combinations against CoR-AB. Among 341 carbapenem-resistant Acinetobacter spp., 317 (92.0%) were identified as A. baumannii by gyrB multiplex PCR. The rate of colistin resistance was 15.1% in A. baumannii isolates with MIC range of 0.125 – 64 mg/L. A total of 30 representative …


Application Of Phage Display Technology For The Production Of Antibodies Againststreptococcus Suis Serotype 2, Pattarawadee Sulong Jan 2020

Application Of Phage Display Technology For The Production Of Antibodies Againststreptococcus Suis Serotype 2, Pattarawadee Sulong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Streptococcus suis (S. suis) serotype 2 infection is problematic in the swine industry and responsible for most cases of human infection worldwide. Since current multiplex PCR cannot differentiate between serotypes 2 and 1/2, then serotype-specific antibodies (Abs) are required for serotype identification to confirm S. suis serotype 2 infection. This study aimed to generate Abs specific to S. suis serotype 2 by phage display from a human heavy chain variable domain (VH) antibody library. For biopanning, whole cells of S. suis serotype 2 were used as the target antigen. With increasing selection stringency, we could select the VH Abs that …


Molecular Detection Of Viable Mycobacterium Tuberculosis Complex In Clinical Specimens, Suthidee Petsong Jan 2020

Molecular Detection Of Viable Mycobacterium Tuberculosis Complex In Clinical Specimens, Suthidee Petsong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Tuberculosis (TB) is the global health concern because of the rising incidence and mortality. TB is caused by Mycobacterium tuberculosis complex (MTBC) and transmitted via inhalation of infectious droplet nuclei circulating in the air. The World Health Organization (WHO) recommends the use of Acid-fast (AFB) smear microscopy, MTBC culture, and molecular detection of MTBC DNA for diagnosis of TB. The response to treatment should be acquired as soon as possible to reduce disease transmission and drug resistance. Although MTBC culture is a gold standard, it is laborious, expensive, and may take up to 8 weeks. The AFB staining and molecular …


Detection Of Leptospires By Rpa-Nalfia And Crispr-Cas12a, Sirawit Jirawannaporn Jan 2020

Detection Of Leptospires By Rpa-Nalfia And Crispr-Cas12a, Sirawit Jirawannaporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

The key barrier in leptospirosis diagnosis is a lack of available sensitive point-of-care testing. Therefore, we aimed to develop and validate nucleic acid lateral flow immunoassay (NALFIA) and clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 12a (CRISPR/Cas12a) platform combined with isothermal amplification to detect leptospires from extracted patients' DNA samples. A recombinase polymerase amplification (RPA)-NALFIA and RPA-CRISPR/Cas12a assay was designed to detect the LipL32, SecY and lfb1 genes of pathogenic Leptospira spp. The RPA-NALFIA targeting LipL32 observed the LOD at 105 copies/reaction. In comparison, the RPA-CRISPR/Cas12a targeting LipL32 and SecY demonstrated a limit of detection (LOD) of 100 copies/reaction, …


The Influence Of Polycyclic Aromatic Hydrocarbons In Fcgriib -/- Lupus Mice, Kanyarat Udompornpitak Jan 2020

The Influence Of Polycyclic Aromatic Hydrocarbons In Fcgriib -/- Lupus Mice, Kanyarat Udompornpitak

Chulalongkorn University Theses and Dissertations (Chula ETD)

The activation of aryl hydrocarbon receptor (Ahr) through polycyclic aromatic hydrocarbons (PAHs), the major components of particulate matter at 2.5 micron (PM2.5) in the polluted air, might aggravate inflammation and lupus activity. Hence, 1,4-chrysenequinone (1,4-CQ), a substance in the PAHs group, was tested in a lupus model from FcgRIIb deficiency (FcgRIIb-/-) using macrophages and mice. Although the activation by 1,4-CQ alone was unable to induce inflammation, the pre-conditioning by lipopolysaccharide (LPS), a representative inflammatory-activator, before 1,4-CQ (LPS/1,4-CQ) induced more predominant inflammation in macrophages when compared with LPS or 1,4-CQ activation alone as determined by supernatant cytokines (TNF-α, IL-6 and IL-10). …


Synergistic Activities Of Antibiotic Combinations Against Carbapenem-Resistant Klebsiella Pneumoniae And Mechanisms Of Carbapenem Resistance In Klebsiella Pneumoniae Clinical Isolates., Netchanok Muhummudaree Jan 2020

Synergistic Activities Of Antibiotic Combinations Against Carbapenem-Resistant Klebsiella Pneumoniae And Mechanisms Of Carbapenem Resistance In Klebsiella Pneumoniae Clinical Isolates., Netchanok Muhummudaree

Chulalongkorn University Theses and Dissertations (Chula ETD)

Carbapenem-resistant Klebsiella pneumoniae (CRKP) has been increasing reported worldwide. The aims of this study were to investigate the mechanisms of carbapenem resistance in K. pneumoniae Thai isolates and study the synergistic activities of antibiotic combinations against CRKP isolates. Two-hundred and forty CRKP clinical isolates were obtained from patients at King Chulalongkorn Memorial Hospital between September 2016 and April 2020. The antibiotic susceptibility testing was determined by agar dilution to imipenem, meropenem, amikacin, fosfomycin, ciprofloxacin and by broth microdilution to colistin. The prevalence rates of resistance to imipenem, meropenem, ciprofloxacin, fosfomycin, amikacin, and colistin were 90.42%, 91.67%, 95.84%, 41.25%, 20%, and …


Role Of Chondrocyte Antigen Presentation In Osteoarthritis, Panjana Sengprasert Jan 2020

Role Of Chondrocyte Antigen Presentation In Osteoarthritis, Panjana Sengprasert

Chulalongkorn University Theses and Dissertations (Chula ETD)

Osteoarthritis (OA) is an inflammatory disorder characterized by degeneration of joint components, especially the cartilage. Chondrocytes are found in articular cartilage and play a role in cartilage production and degradation. Several studies found that chondrocytes not only control the cartilage metabolism, but also play a role in immune responses. However, the role of chondrocytes in the pathogenesis of OA is still unclear. In this study, we investigated the responses of OA chondrocytes after stimulating with IFN-γ and proteoglycan aggrecan and also determined antigen presentation function of chondrocytes to present proteoglycan aggrecan peptide to T cells. We found that OA chondrocyte …


Characterization Of Carbon Storage Regulator A (Csra) Homolog As A Global Gene Regulator In Leptospira Spp., Theerapat Phoka Jan 2020

Characterization Of Carbon Storage Regulator A (Csra) Homolog As A Global Gene Regulator In Leptospira Spp., Theerapat Phoka

Chulalongkorn University Theses and Dissertations (Chula ETD)

Leptospira spp. consist of non-pathogenic and pathogenic species. The bacteria can survive in diverse environments and therefore need mechanisms of rapid adaptation to environmental changes. However, molecular mechanisms of stress response in Leptospira are not fully understood. Carbon Storage Regulator A (CsrA) is a well-characterized, conserved, post-transcriptional global regulator that plays a critical role in response to environmental changes in many bacteria. CsrA has been reported to regulate several pathways such as glycogen metabolism, motility, biofilm formation, and virulence-associated genes. Based on available genomics data of Leptospira spp., we found putative csrA homolog, approximately 50% similarity with csrA of E. …


The Differential Dendritic Cell Properties In Response To Candida Albicans And Non-Albican Candida Β-Glucan, Truc Thi Huong Dinh Jan 2020

The Differential Dendritic Cell Properties In Response To Candida Albicans And Non-Albican Candida Β-Glucan, Truc Thi Huong Dinh

Chulalongkorn University Theses and Dissertations (Chula ETD)

Increased mortality and antifungal drug resistance of non-albicans Candidiasis patients have become an alarming in health problems nowadays, whereas profound knowledge of their pathogenesis mechanisms is still limited. The immune responses of innate and adaptive immunity play a crucial role in protecting from Candida infections. Dendritic cells (DCs) are the most notable because of their roles in bridging an innate immunity and specific adaptive immunity to eliminate fungal invasion. It is little known about DC functions in non-albicans Candida (NACs) infections. Besides, there is less study on evaluating the DC properties upon the interaction between DCs and NACs-derived ß-glucans. Therefore, …


Neutrophil Extracellular Traps (Nets) Formation Of Fcgr2b Deficient Mice In Lupus Mouse Model With Ischemic Reperfusion Injury, Wilasinee Saisorn Jan 2020

Neutrophil Extracellular Traps (Nets) Formation Of Fcgr2b Deficient Mice In Lupus Mouse Model With Ischemic Reperfusion Injury, Wilasinee Saisorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Acute kidney injury (AKI) caused by renal ischemic reperfusion (I/R) is the most prevalent cause of morbidity and mortality in patients. Neutrophil extracellular traps (NETs) are important for the progression of lupus nephritis after renal I/R injury. Because neutrophils are the first immune cell that respond to tissue damage, neutrophils might be an important cell that determines renal I/R injury. Additionally, NET components, including cell-free DNA, histone, nucleosome, and cytoplasmic protein compartment release the auto-antigens that accelerate lupus disease activity. Therefore, this project aimed to compare NETs formation in several internal organs following renal I/R injury in Fcgr2b deficient (Fcgr2b-/-) …


The Antiviral Activity Of Lichen Metabolites Against Dengue Virus, Naphat Loeanurit Jan 2020

The Antiviral Activity Of Lichen Metabolites Against Dengue Virus, Naphat Loeanurit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Dengue fever is one of the mosquito-borne infectious diseases globally. Currently, no specific treatment was established. Depsidones and depsides are one of the most common lichen secondary metabolites produced for the organism’s survival in extreme environments. These compounds have been reported as antivirals against the other virus in Flaviviridae family, hepatitis C virus. In this study, depsidones and depsides were explored for anti-dengue efficacy and cellular toxicity. One depsidone, VK-0014, and two depsides, TT-031 and TT-032, exhibited an anti-DENV2 with effective concentration (EC50) of 17.42 ± 3.21, 2.43 ± 0.19, and 0.91 ± 0.15 µM, respectively. Cytotoxicity concentration (CC50) in …


The Role Of Chromatin Structure In Cellular Responses To Bacterial Cytolethal Distending Toxin In Saccharomyces Cerevisiae Model, Siriyod Denmongkholchai Jan 2019

The Role Of Chromatin Structure In Cellular Responses To Bacterial Cytolethal Distending Toxin In Saccharomyces Cerevisiae Model, Siriyod Denmongkholchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cytolethal distending toxin subunit B (CdtB) is a DNase I-like bacterial genotoxin that causes DNA damage leading to cell cycle arrest and cell death. Previous reports demonstrated that CdtB has low level of DNase activity in vitro. Besides, a mutation at histone H2B phosphorylation site required for chromatin condensation during apoptosis (S10A) conferred partial resistance to CdtB in Saccharomyces cerevisiae model. Therefore, we hypothesized that chromatin structure may affect CdtB function. In this study, we identified chromatin regulators required for CdtB cytotoxicity in yeast. We found that deletions of certain components of SWR-complex (SWR1, SWC2, SWC5, SWC6, and ARP6), INO80-complex …


The Incidence Of Antibiotic-Resistant Staphylococcus Spp. Colonization And Infection In Children And Adults With Atopic Dermatitis, Matchima Laowansiri Jan 2019

The Incidence Of Antibiotic-Resistant Staphylococcus Spp. Colonization And Infection In Children And Adults With Atopic Dermatitis, Matchima Laowansiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Atopic dermatitis (AD) is an inflammatory skin disease characterized by chronic and recurrent eczematous rash. AD occurs in both children and adults, but children are more affected. An important aggravating factor is caused by Staphylococcus aureus (S. aureus) infection. Therefore, topical (beta-lactam, macrolides, clindamycin) and systemic (mupirocin and fusidic acid) antibiotics are essential for treatment of AD. However, frequent use of antibiotics results in an increase in the incidence of antibiotic-resistant S. aureus. Methicillin resistance S. aureus (MRSA) becomes a problem in the treatment of skin diseases. It’s found that the change from penicillin binding protein (PBP) to PBP2a with …