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Chulalongkorn University Theses and Dissertations (Chula ETD)

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Functional And Transcriptomic Changes In Synergy Of Endotoxin And (1->3)-Β-D-Glucan In Bone Marrow Derived Macrophage From Fc Gamma Receptor Iib Deficient Mice, Jiraphorn Issara-Amphorn Jan 2019

Functional And Transcriptomic Changes In Synergy Of Endotoxin And (1->3)-Β-D-Glucan In Bone Marrow Derived Macrophage From Fc Gamma Receptor Iib Deficient Mice, Jiraphorn Issara-Amphorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Systemic lupus erythematosus (SLE) is an autoimmune disease with a diverse array of clinical symptoms. There are many factors including environmental factors may trigger disease progression. In this study, we investigated the influence of spontaneous gut leakage upon polymicrobial sepsis in Fc gamma receptor IIb deficient (FcgRIIb-/-) mice aged 8 and 40 weeks, as representing asymptomatic and symptomatic lupus, respectively. The spontaneous gut leakage as determined by i) the level of serum FITC-dextran, ii) increased serum endotoxin (LPS), and iii) increased serum (1->3)-b-D-glucan (BG), were demonstrated in symptomatic FcgRIIb-/- mice, but not in asymptomatic group. Moreover, spontaneous gut leakage …


Effects Of Non-Albicans Candida Species On Biofilm Formation And Acidogenicity Of Dual-Species Biofilms And On Cariogenic Virulence Gene Expression Of Streptococcus Mutans, Wirunphat Sansanoa Jan 2019

Effects Of Non-Albicans Candida Species On Biofilm Formation And Acidogenicity Of Dual-Species Biofilms And On Cariogenic Virulence Gene Expression Of Streptococcus Mutans, Wirunphat Sansanoa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Early childhood caries is a common oral disease found in children which could affect their general health. Streptococcus mutans is an important cariogenic pathogen since it possesses cariogenic properties, which are acid production, acid tolerance and biofilm formation. Recent studies showed that Candida albicans, which is frequently found together with S. mutans in plaques of children with dental caries, enhances cariogenicity. At the same time, increasing prevalence of non-albicans Candida species (NACs) in children and immune-compromised patients has been reported. Therefore, this study aims to investigate the effects of NACs when co-cultured with S. mutans on cariogenic properties and virulence …


Effects Of Non-Albicans Candida Species On Biofilm Formation And Acidogenicity Of Dual-Species Biofilms And On Cariogenic Virulence Gene Expression Of Streptococcus Mutans, Wirunphat Sansanoa Jan 2019

Effects Of Non-Albicans Candida Species On Biofilm Formation And Acidogenicity Of Dual-Species Biofilms And On Cariogenic Virulence Gene Expression Of Streptococcus Mutans, Wirunphat Sansanoa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Early childhood caries is a common oral disease found in children which could affect their general health. Streptococcus mutans is an important cariogenic pathogen since it possesses cariogenic properties, which are acid production, acid tolerance and biofilm formation. Recent studies showed that Candida albicans, which is frequently found together with S. mutans in plaques of children with dental caries, enhances cariogenicity. At the same time, increasing prevalence of non-albicans Candida species (NACs) in children and immune-compromised patients has been reported. Therefore, this study aims to investigate the effects of NACs when co-cultured with S. mutans on cariogenic properties and virulence …


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 …


The Effect Of A Trehalase Inhibitor, Validamycin A, On The Growth Of Aspergillus Flavus, Napasawan Plabutong Jan 2019

The Effect Of A Trehalase Inhibitor, Validamycin A, On The Growth Of Aspergillus Flavus, Napasawan Plabutong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Aspergillus flavus is a fungus found in the environment causing keratitis, cutaneous infections, sinusitis, invasive pulmonary aspergillosis in humans. Although this fungus can be treated with antifungal agents, these main antifungal agents have many side effects. Trehalase is an enzyme for digesting trehalose into two glucose subunits and is essential for virulence in many fungi. A trehalase inhibitor, called validamycin A, has been used effectively against a rice fungal pathogen, Rhizoctonia solani. In this study, we observed that validamycin A increased trehalose levels significantly in A. flavus spores and delayed the germination of those spores. In addition, to further investigate …


Development Of Polymerase Chain Reaction Enzyme Linked Immunosorbent Assay For Detection Of Human Papillomavirus 16 L1 Gene Methylation, Sasiprapa Liewchalermwong Jan 2019

Development Of Polymerase Chain Reaction Enzyme Linked Immunosorbent Assay For Detection Of Human Papillomavirus 16 L1 Gene Methylation, Sasiprapa Liewchalermwong

Chulalongkorn University Theses and Dissertations (Chula ETD)

It has been well known that cervical cancer is caused by persistent infections with the high risk human papillomavirus (HR-HPV) especially HPV16 and 18. However, a minority of HR-HPV infected women developed cancer, therefore, triage test is necessary to particularly select some HR-HPV infected women who are at higher risk to progress to cervical cancer quickly for colposcopy examination. Since HPV16 L1 gene hypermethylation has been reported to be correlated well with high grade cervical lesions and cancer, the present study aims to develop PCR-ELISA for detection of HPV16 L1 gene methylation. Cervical cells were collected from women who referred …


Characterization Of Mait Tcr Repertoire Of Gastrointestinal Tract And Peripheral Blood Mait Cells, Thidarat Kongkaew Jan 2019

Characterization Of Mait Tcr Repertoire Of Gastrointestinal Tract And Peripheral Blood Mait Cells, Thidarat Kongkaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mucosal-associated invariant T (MAIT) cells are an innate-like T cell that rapidly respond to infection. MAIT cells are αβ T cells that possess a Vα7.2 (TRAV1-2) TCR with mostly pairing to TRAJ33, TRAJ20 or TRAJ12 and predominantly TRBV20-1, TRBV6-1 and TRBV6-4. MAIT T cell receptors (TCR) repertoire have been previously studied in peripheral blood. However, data on MAIT TCR repertoire in gastrointestinal tract are lacking. We studied 2 individuals who are underwent esophagogastroduodenoscopy (EGD) and colonoscopy. Blood and biopsies were obtained. PBMCs were isolated from blood and LPLs were isolated from biopsies. Due to the low number of MAIT cells …


Identification Of Probiotic Bacteria With Anticancer Activity Against Colorectal Cancer In Vitro, Patcharin Prakobwat Jan 2019

Identification Of Probiotic Bacteria With Anticancer Activity Against Colorectal Cancer In Vitro, Patcharin Prakobwat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Colorectal cancer is the third most common cause of cancer death worldwide. It is ranked third for new cancer patients in Thailand. Colorectal cancer is associated with multifactorial risk factors including the imbalance of gut microbiota. This project aimed to identify Lactobacillus strains isolated from Thai healthy populations that have anticancer activities against colorectal cancer in vitro. Lactobacillus cultured media (LCM) obtained from thirty-nine Lactobacillus strains, previously shown to have anti-inflammatory activity, were selected and used at different concentrations and/or pH adjustment to determine the anti-proliferative effect on HT-29 and Caco-2 colon cancer cells at 24, 48, and 72 h. …


Characterization Of Leptospiral Extracellular Vesicles In Stress Conditions, Eakalak Phanchamnan Jan 2018

Characterization Of Leptospiral Extracellular Vesicles In Stress Conditions, Eakalak Phanchamnan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pathogenic Leptospira spp. is a causative agent of leptospirosis, a worldwide zoonosis with public health concern especially in the urban slum of metropolis and rural areas in tropical and subtropical countries. The pathogenesis of leptospirosis remains elusive. Extracellular vesicles (ECVs), which pinch off from the bacterial membranes, simultaneously harbor multiple active molecules that may serve as a secretion system, communication tool, and vaccine candidates. Recently, chemically induced leptospiral ECVs were studied and used as vaccine candidates. However, the naturally produced leptospiral ECVs has not been characterized. This study aimed to identify proteins in leptospiral ECVs produced under stress conditions including …


Comprehensive Proteomics Identification Of Ifn-Λ3-Regulated Antiviral Proteins In Hbv-Transfected Cells, Jiradej Makjaroen Jan 2018

Comprehensive Proteomics Identification Of Ifn-Λ3-Regulated Antiviral Proteins In Hbv-Transfected Cells, Jiradej Makjaroen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Interferon (IFN)-λ is a relatively unexplored, yet promising anti-viral agent. IFN-λ has recently been tested in clinical trials of chronic hepatitis B, with the advantage that side effects may be limited compared with IFN-α, as IFN-λ receptors are found only in epithelial cells. To date, IFN-λ downstream signaling pathway remains largely unelucidated, particularly via proteomics methods. Here, we report that IFN-λ3 inhibits HBV replication in HepG2.2.15 cells, reducing levels of both HBV transcripts and intracellular HBV DNA. Quantitative proteomic analysis of HBV-transfected cells was performed following 24-hour IFN-λ3 treatment, with parallel IFN-α2a and PBS treatments for comparison using a dimethyl …


Mechanisms Of Ceftriaxone Resistance In Neisseria Gonorrhoeae Isolated From Thai Patients, Naris Kueakulpattana Jan 2018

Mechanisms Of Ceftriaxone Resistance In Neisseria Gonorrhoeae Isolated From Thai Patients, Naris Kueakulpattana

Chulalongkorn University Theses and Dissertations (Chula ETD)

N. gonorrhoeae is the causative agent of gonorrhea, which is one of the most important sexually transmitted disease. The multidrug resistance in N. gonorrhoeae has been increasingly reported worldwide. The objectives of this study were to investigate the prevalence and the mechanisms of ceftriaxone resistance in N. gonorrhoeae Thai isolates, and to investigate the synergistic activities of antibiotic combinations against N. gonorrhoeae isolates with reduced susceptibility or resistance to ceftriaxone. A total of 134 N. gonorrhoeae isolates were included in this study. The resistance rates of ciprofloxacin, tetracycline, penicillin G, gentamicin, azithromycin, ertapenem, fosfomycin, cefixime, and ceftriaxone were 90.30%, 82.09%, …


The Role Of Histone Methylation Of H3k4 In Polarization Of Macrophages Stimulated By Immune Complex And Lipopolysaccharide And Its Therapeutic Potential In Sepsis, Vichaya Ruenjaiman Jan 2018

The Role Of Histone Methylation Of H3k4 In Polarization Of Macrophages Stimulated By Immune Complex And Lipopolysaccharide And Its Therapeutic Potential In Sepsis, Vichaya Ruenjaiman

Chulalongkorn University Theses and Dissertations (Chula ETD)

Macrophage plasticity is a process that allows macrophages to switch between two opposing phenotypes based on differential stimuli. Functional plasticity of macrophages contributes to disease pathogenesis such as cancer, metabolic diseases, autoimmune diseases and systemic infections. Epigenetics plays an important role in regulating this process. Macrophages stimulated with lipopolysaccharide (LPS) (M(LPS)) produce high level of pro-inflammatory cytokines such as IL-12, TNFα and IL-6 and low level of anti-inflammatory cytokine IL-10, while macrophages stimulated with LPS in the presence of immune complex (IC) (M(IC)) produce high level of IL-10 and low level of IL-12. In this study, we investigated the plasticity …


The Severity Of Cryptococcus Neoformans Infection In Fc Gamma Receptor Iib Deficient Mice, Saowapha Surawut Jan 2018

The Severity Of Cryptococcus Neoformans Infection In Fc Gamma Receptor Iib Deficient Mice, Saowapha Surawut

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cryptococcus neoformans, an encapsulated yeast commonly infecting the central nervous system, refers to as cryptococcal meningitis or cryptococcosis is commonly found in Thailand. C. neoformans is able to replicate, survive inside host macrophages, evade from the cells and use macrophages as a vehicle to disseminate to the target organs, a mechanism known as Trojan horse. Therefore, the containment of C. neoformans in phagocytic cell is important for host protective immunity. Cryptococcosis is common in immunocompromised host such as in patients with low CD4+ T helper cells in HIV-infection and patients taking immunosuppressive drugs. However, the incidence of cryptococcosis in healthy …


Hsv-1 Induces Filopodia Formation In Activated T Lymphocytes, Thanayod Sasivimolrattana Jan 2018

Hsv-1 Induces Filopodia Formation In Activated T Lymphocytes, Thanayod Sasivimolrattana

Chulalongkorn University Theses and Dissertations (Chula ETD)

Herpes simplex virus type 1 (HSV-1) is a widespread pathogen, which has diverse clinical manifestations from mild localized infection to severe systemic infection. The tissue tropism of HSV-1 is mainly epithelial and mucosal cells. However, it can also multiply in T lymphocytes suggesting a cause of viremia. In this study, CD3+CD4-CD8- Jurkat T lymphocytes were used. Under activation, up-regulation of CD69 molecules on cell surface was observed. Increase yield of HSV-1 production in activated T lymphocytes was demonstrated. In addition, most of HSV-1 virion progenies from infected T lymphocytes were released extracellularly, suggesting the cause of dissemination. The mechanism which …


Development Of Gold Nanoparticle-Based Lateral Flow Immunoassay For Detection Of Pathogenic Leptospiral Antigen, Prayoon Lae-Ngee Jan 2017

Development Of Gold Nanoparticle-Based Lateral Flow Immunoassay For Detection Of Pathogenic Leptospiral Antigen, Prayoon Lae-Ngee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Leptospirosis, caused by pathogenic Leptospira spp., is a global re-emerging zoonosis and endemic disease in tropical and sub-tropical countries including Thailand. Point-of-care testing (POCT) for rapid diagnosis of leptospirosis is needed for prompt and appropriate treatment particularly in resource-poor settings. Lateral flow immunoassay (LFA)-based POCT devices are rapid, user friendly, cheap, have one-step analysis, and need no sophisticated equipment. LipL32 is a common target for diagnostic tests of leptospirosis because it is the major outer membrane protein (OMP) that is specific and highly conserved among pathogenic Leptospira. This study aimed to develop the gold nanoparticle (AuNP)-based LFA for detection of …


Characterization Of Antimicrobial-Resistant Nontyphoidal Salmonella Isolated From Humans And Food Animals In Thailand 172252256, Sirirat Luk-In Jan 2017

Characterization Of Antimicrobial-Resistant Nontyphoidal Salmonella Isolated From Humans And Food Animals In Thailand 172252256, Sirirat Luk-In

Chulalongkorn University Theses and Dissertations (Chula ETD)

The emergence and increase of resistance to antimicrobial agents, especially to extended-spectrum cephalosporins (ESCs) and fluoroquinolones in nontyphoidal Salmonella have recently become a serious therapeutic problem. The objectives of this study were to characterize antimicrobial resistance mechanisms, the clonality, and plasmid profiles among nontyphoidal Salmonella isolates from human and food animals in Thailand. A total of 897 nontyphoidal Salmonella isolates, 617 isolates from human and 280 isolates from food animal in Thailand during 2005 to 2007 and 2012 to 2016 were included in this study. The significantly higher resistance rates were found in S. Choleraesuis compared with other serotypes to …


Antimicrobial Effect Of High Dose Ascorbate In Mouse Model With Bacterial Infection, Chulamartd Wirapakorn Jan 2017

Antimicrobial Effect Of High Dose Ascorbate In Mouse Model With Bacterial Infection, Chulamartd Wirapakorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Ascorbate or Vitamin C is a vitamin that is important to the body. It contributes to the immunity, involves the collagen formation, acts as an antioxidant and has the ability to destroy cancer cells and bacteria. These abilities depend on the concentration of ascorbate. Bactericidal properties of ascorbate were interesting, especially in the high concentrations. Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, and Escherichia coli are a common etiologies of nosocomial infection in Thailand and worldwide. These bacteria have developed mechanisms of antibiotics resistance and cause more violence in the disease. Hence, the time-killing assay was used to explore the bactericidal …


Involvement Of Notch Signaling In Interleukin-4-Stimulated Human Macrophages, Naunpun Sangphech Jan 2017

Involvement Of Notch Signaling In Interleukin-4-Stimulated Human Macrophages, Naunpun Sangphech

Chulalongkorn University Theses and Dissertations (Chula ETD)

Macrophages respond to various stimuli, resulting in distinct effector phenotypes that range from LPS-stimulated proinflammatory to IL-4-activated pro-healing phenotype. The regulatory mechanism of this polarization is not fully understood. Notch signaling pathway is a conserved signaling pathway involved in polarization of macrophages, especially proinflammatory macrophages. However, the role of Notch signaling in IL-4 stimulated macrophages (M(IL-4)) is not well defined. PPARgamma is a signature nuclear receptor in M(IL-4) that function mainly in regulating lipid metabolism. There are many reports that revealed the interaction of Notch signaling and PPARgamma in various cells but not in macrophages. In this study, the interaction …


Ctl-Mediated Immune Evasion In Hiv Viraemic Controllers And Non-Controllers, Prathanporn Kaewpreedee Jan 2017

Ctl-Mediated Immune Evasion In Hiv Viraemic Controllers And Non-Controllers, Prathanporn Kaewpreedee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Objective: To compare T cell response and to identify the mechanism of escape in HIV-infected volunteers. Methods: HIV-infected volunteers (CD4>450 cells/µL) were enrolled from the anonymous clinic. Volunteers were classified into two groups based on HIV plasma viral load; viraemic controllers (VC) (VL<2000 cp/mL) and non-controllers (NC) (VL>2000 cp/mL). EDTA-whole blood was collected and determined the response against Gag p24 by IFNγ ELISpot assay. Population sequencing within the Gag p24 region was performed to identify escape mutations. Results: Demographic data [age, gender, sexual preference and the presence of protective alleles (HLA-B27, -B57 and –B58)] between VC (n=23) and NC (n=41) were no statistical …


Gold Nanoparticles In Clp Model And Mechanism In Bone Marrows Derived Macrophages Cell For Sepsis Severity Attenuation, Sujittra Taratummarat Jan 2017

Gold Nanoparticles In Clp Model And Mechanism In Bone Marrows Derived Macrophages Cell For Sepsis Severity Attenuation, Sujittra Taratummarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Sepsis is still a major worldwide- public health problem as a leading cause of the high mortality rate condition. Sepsis is the inflammatory condition in host due to bacterial infections. Sepsis severity depends on the individual's immune responses and the organism virulence factor. The current strategies for sepsis treatment are based, mainly on, symptomatic treatment with antibiotics. However, the adjuvant therapy in sepsis is interesting. Gold nanoparticles are anti-inflammatory drug from the ancient time which is still currently used for the treatment of rheumatoid arthritis. Thus, we hypothesized that gold nanoparticles could be effective in reducing an inflammation in sepsis …


Characterization Of T Cell Secreted Cytokines And Cytotoxic Mediators Profiling In Knee Osteoarthritis Patients, Thitiya Sae-Jung Jan 2017

Characterization Of T Cell Secreted Cytokines And Cytotoxic Mediators Profiling In Knee Osteoarthritis Patients, Thitiya Sae-Jung

Chulalongkorn University Theses and Dissertations (Chula ETD)

Osteoarthritis (OA) is a chronic disease associated with morphological joint changes that results in the breakdown of joint cartilage and underlying bone with erosive inflammation. Factors of OA are intrinsic factor and extrinsic factor. The pathogenesis of OA relates with immune responses and immune cells, T cells, B cells, and macrophages etc., T cells both CD4+ and CD8+ T cell are immune cells that have been suggested to play a role in OA. However, we found many finding in CD8+ T cells such as a high proportion of CD8+ T cell was observed in tissue of knee joint. In addition, …


Immune Response In Pythiosis Patients Treated With Pythium Insidiosum Antigen (Pia), Navaporn Worasilchai Jan 2017

Immune Response In Pythiosis Patients Treated With Pythium Insidiosum Antigen (Pia), Navaporn Worasilchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Immunotherapy using Pythium insidiosum antigen (PIA) is one of the combination treatment for P. insidiosum infected patients along with amputation and certain antifungal agents. The protocol of first prime (day0) after diagnosis and six booster doses (at 0.5, 1, 1.5, 3, 6, 12 months; mo.) along a year period were performed based on previous study. The switching of T-helper2 (Th2) to Th1 after immunotherapy along with the clinical improvement in equine and rabbit models were revealed whereas studies in human are very limited. To investigate the immune response in PIA treated pythiosis patients, cytokine profile (CMI response), P. insidiosum specific …


The Antiviral Activity Of Phenolic Lipids Group Against Dengue Virus, Parichat Kanyaboon Jan 2017

The Antiviral Activity Of Phenolic Lipids Group Against Dengue Virus, Parichat Kanyaboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Dengue virus causes a global burden that specific chemotherapy has not been established in a clinical setting. A previous report suggested that anacardic acid saturated (C15:0), a member of phenolic lipids, inhibited hepatitis C virus infection. Here, we explored structure activity relationship of phenolic lipids homologues with anti-DENV properties in the cell-based system. Our results indicated that Cardol triene (C15:3) expressed DENV1-4 inhibition, but not to Zika virus (SV0010/15) with the EC50s of 5.35 ± 1.16 µM, 7.13 ± 0.72 µM, 8.98 ± 1.77 µM, and 8.21 ± 0.34 µM, respectively. Also, the compound showed good CC50s to Vero cells …


Induction Of Interleukin-1 Receptor Antagonist (Il-1ra) By Porcine Reproductive And Respiratory Syndrome Virus (Prrsv), Teerawut Nedumpun Jan 2017

Induction Of Interleukin-1 Receptor Antagonist (Il-1ra) By Porcine Reproductive And Respiratory Syndrome Virus (Prrsv), Teerawut Nedumpun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Porcine respiratory and reproductive syndrome virus (PRRSV) is one of the major pathogens affecting pig production industry worldwide. Impaired innate and adaptive immune responses are evidenced through the course of PRRSV infection. Several evidences indicate that PRRSV suppresses host immune responses via several immune evasion strategies. Interleukin-1 receptor antagonist (IL-1Ra) is known as an early inhibitory cytokine that suppresses innate immune functions and T lymphocyte responses. The aims of this study were to explore the induction of IL-1Ra by PRRSV and the negative immunomodulatory effects of PRRSV-induced IL-1Ra on porcine immune responses. In this study, the previous monocytes-derived dendritic cells …