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Potential Of Nanoscale Elements To Control Fusarium Wilt Disease In Tomato (Solanum Lycopersicum), Enhance Macronutrient Use Efficiency, And Increase Its Yield, Ishaq Olarewaju Adisa 2019 University of Texas at El Paso

Potential Of Nanoscale Elements To Control Fusarium Wilt Disease In Tomato (Solanum Lycopersicum), Enhance Macronutrient Use Efficiency, And Increase Its Yield, Ishaq Olarewaju Adisa

Open Access Theses & Dissertations

Nanotechnology has a great potential in ensuring food production, security and safety globally. Over the past decade, research on the use of nanomaterials to supply nutrient elements and protect plants from pest and diseases has significantly increased. Tomato (Solanum lycopersicum) is one of the most consumed vegetables in the world and United State is one of its largest producers globally generating billions of dollars annually in revenue.. Tomato plants are affected worldwide by Fusarium wilt caused by Fusarium oxysporum f. sp. Lycopersici. There is growing concern about excessive use of conventional pesticides in controlling Fusarium and other diseases in tomato …


Characterization Of The Effects Of Sex And Estrogen Receptor Signaling On Antigen-Specific T Cells For Immunotherapy, Flor Cecilia Navarro Negredo 2019 Loyola University Chicago

Characterization Of The Effects Of Sex And Estrogen Receptor Signaling On Antigen-Specific T Cells For Immunotherapy, Flor Cecilia Navarro Negredo

Dissertations

Adoptive cell transfer (ACT) immunotherapy using antigen (Ag)-specific T cells is partially effective treating several malignancies but numerous challenges remain in order to improve its therapeutic potential. The roles of host factors, such as sex hormone receptor signaling, that can affect the T cell anti-tumor function remain understudied. The work performed in this dissertation characterized the role of estrogen signaling on T cell function in vitro, and during ACT immunotherapy against hepatocellular carcinoma (HCC) in vivo. Estrogen signaling through ERa enhanced the expression and secretion of Type I effector cytokines including IFNg, TNFa, and Granzyme B in male and female …


Yczr, A New Case Of Plp-Dependent Mocr/Gabr Type Transcription Regulator In Klebsiella Pneumonia, Yuanzhang Zheng 2019 Loyola University Chicago

Yczr, A New Case Of Plp-Dependent Mocr/Gabr Type Transcription Regulator In Klebsiella Pneumonia, Yuanzhang Zheng

Dissertations

Increasing number of genes encoding PLP-dependent transcription regulators, MocR/GabR type regulators, have been identified in various bacterial genomes. However, only a handful of them, including MocR, PdxR and GabR have been studied experimentally. They control different aspects of the bacterial metabolism. Only GabR has reported crystallographic structures. MocR/GabR regulators possess a chimeric structure consisted of a WHTH DNA binding domain and an Aminotransferase-like regulation domain, which can bind PLP as an effector in transcription regulation. Such a chimeric construct presents an interesting case in molecular evolution. The regulation domains of All MocR/GabR type regulators loss their catalytic capacity during evolution …


Co-Expression Of Feedback Resistant Enzymes In Phenylalanine Biosynthesis Pathway To Increase Phenylalanine Production, Charintip Yenyuvadee 2019 Faculty of Science

Co-Expression Of Feedback Resistant Enzymes In Phenylalanine Biosynthesis Pathway To Increase Phenylalanine Production, Charintip Yenyuvadee

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-Phenylalanine (L-Phe) is an important commercial amino acid. It is widely used in food and pharmaceutical industries. Currently, the requirement of L-Phe is increased according to the great demand for the low-calorie sweetener, aspartame. In Escherichia coli, the synthesis of L-Phe is controlled by the multi-hierarchical regulations. AroG isoform of 3-deoxy- D-arabino-heptulosonate-7-phosphate synthase (DAHP synthase) and chorismate mutase/prephenate dehydratase (PheA), two important enzymes, are feedback inhibited by LPhe. Co-expression of feedback-resistant pheA (pheA[superscript L359D]) with other pivotal genes in L-Phe biosynthesis pathway: aroB, aroL, phedh, tktA, aroG, pheA, yddG, and glpF in pRSFDuet-1 (pPTFBLYA[superscript L359D]) elevated L-Phe production of E. …


Functional Characterization Of Cytosolic Ddx41 Sensor In Mediating Antiviral Immune Response In Black Tiger Shrimp Penaeus Monodon, Suthinee Soponpong 2019 Faculty of Science

Functional Characterization Of Cytosolic Ddx41 Sensor In Mediating Antiviral Immune Response In Black Tiger Shrimp Penaeus Monodon, Suthinee Soponpong

Chulalongkorn University Theses and Dissertations (Chula ETD)

DEAD (Asp-Glu-Ala-Asp) box polypeptide 41 (DDX41), a receptor belonging to the DExD family, was recently identified as an intracellular DNA sensor in vertebrates. Here, we investigated the presence of cytosolic DNA sensing, DDX41 in shrimp Penaeus monodon. By searching for gene involved in DNA sensing cascade within the shrimp P. monodon EST database, 3 cDNA fragments exhibited similarity to DDX41 in various species were identified. Sequences assembly resulted in a complete ORF of Penaeus monodon DDX41 (PmDDX41) which has 1868-bp encoding a putative protein of 620 amino acid residues. The multiple sequence alignment of deduced amino acid sequence of PmDDX41 …


Fructooligosaccharide Synthesis By Immobilized Inulosucrase From Lactobacillus Reuteri 121 And Improvement Of Product Pattern Using Site-Directed Mutagenesis, Thanapon Charoenwongpaiboon 2019 Faculty of Science

Fructooligosaccharide Synthesis By Immobilized Inulosucrase From Lactobacillus Reuteri 121 And Improvement Of Product Pattern Using Site-Directed Mutagenesis, Thanapon Charoenwongpaiboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Inulin-type fructooligosaccharides (IFOS) are well-known prebiotics which can be produced from sucrose using bacterial inulosucrase (E.C. 2.4.1.9). However, the use of inulosucrase for IFOS synthesis has some limitations because it also synthesizes some polysaccharides and exhibits lower stability than the fungal enzymes. To overcome these limitations, improvement of inulosucrase was made by using enzyme immobilization and enzyme engineering. First, inulosucrase from Lactobacillus reuteri 121 was immobilized on a novel, high capacity core-shell chitosan beads using glutaraldehyde as a cross-linker. The results showed that both immobilized and free inulosucrase had the same optimum pH (5.5), while the optimum temperature was shifted …


Development Of Paper-Based 3d Cell Culture Devices And Real-Time Biosensing Applications, Naricha Pupinyo 2019 Faculty of Allied Health Sciences

Development Of Paper-Based 3d Cell Culture Devices And Real-Time Biosensing Applications, Naricha Pupinyo

Chulalongkorn University Theses and Dissertations (Chula ETD)

Due to its micro fibrous pores, paper has gained traction in the use as a scaffold for 3D cell culture. To study melanoma mechanism, screening the amount of melanin production and invasion study are major keys for drug development. In this work, we developed paper-based devices for culturing melanoma cells. Through the development process, we obtained the optimal parameters, which were applied for 3 different projects; 1) Anti-melanogenic effect screening, 2) Impedance-based E-screen assay, and 3) A membrane insert for real-time invasion assay. As a result of melanin production from melanocytes, the cells can be easily observed after a few …


Effects And Mechanisms Of Caesalpinia Mimosoides Leaf Extract On Oxidative Stress Resistance And Anti-Aging Activity In Caenorhabditis Elegans And Neurite Outgrowth Activity In Neuro2a Cells, Panthakarn Rangsinth 2019 Faculty of Allied Health Sciences

Effects And Mechanisms Of Caesalpinia Mimosoides Leaf Extract On Oxidative Stress Resistance And Anti-Aging Activity In Caenorhabditis Elegans And Neurite Outgrowth Activity In Neuro2a Cells, Panthakarn Rangsinth

Chulalongkorn University Theses and Dissertations (Chula ETD)

World’s population of older people is rising, dietary supplements promoting healthy lifespan are needed. Moreover, Alzheimer’s disease (AD), an age-related degenerative disease, becomes a public health problem in aging society. Recent reports using cell culture models of AD suggest that amyloid precursor protein (APP), a protein causally related to AD, plays an important role as an inhibitor of neurite outgrowth. Medicinal herbs with neurite outgrowth stimulatory effect may help to prevent and cure AD. Moreover, studies suggest that dietary supplements from plant sources act in preventive nutrition, since they provide antioxidant action against oxidative stress, promote healthspan and prolong lifespan. …


Development Of Cell-Penetrating Peptides Targeting Nuclear And Extra-Nuclear Signaling Pathways In Cancer Cells, Panthita Kaewjanthong 2019 Faculty of Allied Health Sciences

Development Of Cell-Penetrating Peptides Targeting Nuclear And Extra-Nuclear Signaling Pathways In Cancer Cells, Panthita Kaewjanthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Growth factors and hormones often mediate their biological effects through series of protein-protein interaction between cytoplasmic signaling molecules or transcription factors. Interfering of these protein-protein interactions has been shown to reduce or inhibit biological and growth responses to various growth factors and hormones. We previously demonstrated that progesterone receptor (PR) contains a polyproline domain (PPD) which directly interact to Src homology 3 (SH3) domain-containing molecules and expression of PR-PPD inhibits EGFR-mediated NSCLC cell proliferation. In this study, we investigated that the introduction of PR-PPD by cell-penetrating peptide could inhibit EGF-induced NSCLC cell proliferation. PR-PPD was attached to a cancer-specific CPP, …


ผลการปกป้องของสารสกัดใบรางจืดจากการเหนี่ยวนำความเป็นพิษด้วยกลูตาเมตในเซลล์ประสาท Ht-22 ผ่านวิถีออโตฟาจี, วุฒิพงษ์ วงศ์ทิพย์ 2019 คณะสหเวชศาสตร์

ผลการปกป้องของสารสกัดใบรางจืดจากการเหนี่ยวนำความเป็นพิษด้วยกลูตาเมตในเซลล์ประสาท Ht-22 ผ่านวิถีออโตฟาจี, วุฒิพงษ์ วงศ์ทิพย์

Chulalongkorn University Theses and Dissertations (Chula ETD)

หนึ่งในสาเหตุสำคัญของการเกิดโรคความเสื่อมของระบบประสาทนั้นเกิดได้จากภาวะเครียดออกซิเดชันภายในเซลล์ประสาท โดยพบว่าสารสื่อประสาทชนิดกลูตาเมตเมื่อมีระดับสูงผิดปกติสามารถเหนี่ยวนำให้เกิดอนุมูลอิสระและภาวะเครียดออกซิเดชันนำไปสู่การสูญเสียและการตายของเซลล์ประสาทได้ โดยเฉพาะการตายของเซลล์จากการเกิดกระบวนการออโตฟาจีมากเกินไป ซึ่งเป็นกระบวนการที่มีบทบาทสำคัญในการควบคุมการตายของเซลล์ผ่านวิถีอื่นๆ รางจืด (Thunbergia laurifolia) เป็นพืชสมุนไพรไทยมีสรรพคุณในการถอนพิษ ต้านการอักเสบ และ ต้านอนุมูลอิสระได้ดี จุดประสงค์ในการวิจัยครั้งนี้ คือ ศึกษาคุณสมบัติการต้านอนุมูลอิสระของสารสกัดหยาบจากใบรางจืด และการปกป้องการตายของเซลล์ประสาทผ่านวิถีออโตฟาจี จากการเหนี่ยวนำภาวะเครียดออกซิเดชันด้วยกลูตาเมตโดยทดสอบในเซลล์ประสาทส่วนฮิปโปแคมปัสของหนูชนิด HT-22 ใบรางจืดถูกนำมาสกัดด้วยเอทานอล จากผลการทดสอบพบว่าสารสกัดหยาบจากใบรางจืดมีความสามารถในการต้านอนุมูลอิสระ และมีปริมาณสารประกอบ ฟลาโวนอยด์และฟีนอลิกสูง โดยจากการวิเคราะห์ด้วยเครื่อง LC-MS และเปรียบเทียบผลที่ได้กับฐานข้อมูล METLIN-(CA, USA) พบสารออกฤทธิ์สำคัญที่ยังไม่มีรายงานในสารสกัดเอทานอลของใบรางจืด ได้แก่ Apigenin 7-O-glucoside และ 7-Hydroxycoumarin ยิ่งไปกว่านั้นสารสกัดหยาบจากใบรางจืดยังสามารถลดการตายของเซลล์ประสาทจากการเหนี่ยวนำความเป็นพิษด้วยกลูตาเมต โดยสามารถยับยั้งการเกิดอนุมูลอิสระภายในเซลล์ และเพิ่มการแสดงออกของยีนต้านอนุมูลอิสระที่ทำหน้าที่สำคัญในกระบวนการต้านอนุมูลอิสระในร่างกาย ได้แก่ superoxide dismutase 1 และ 2 (SOD1 and SOD2) catalase (CAT) และ glutathione peroxidase (GPx) ซึ่งสัมพันธ์กับการลดการเกิดกระบวนการออโตฟาจีภายในเซลล์และเพิ่มปริมาณ ไมโตคอนเดรียโปรตีน โดยพบว่าสารสกัดหยาบจากใบรางจืดสามารถลดอัตราส่วนการแสดงออกของโปรตีน LC3B-II/LC3B-I และเพิ่มการแสดงออกของไมโตคอนเดรียโปรตีน TOM20 เมื่อทำการตรวจหาตำแหน่งที่จำเพาะต่อการแสดงออกของโปรตีนในกระบวนการออโตฟาจี (LC3B) และไมโตคอนเดรียด้วยกล้องจุลทรรศน์ชนิดคอนโฟคอล พบว่า สารสกัดหยาบจากใบรางจืดสามารถลดการเกิด LC3-puncta ซึ่งเป็นลักษณะเด่นของการเกิดกระบวนการออโตฟาจี นอกจากนี้สารสกัดหยาบจากใบรางจืดยังลดการ colocalization ของ LC3B และไมโตคอนเดรีย จากผลการศึกษานี้เราพบสารออกฤทธิ์สำคัญใหม่ที่ยังไม่มีรายงานมาก่อนของใบรางจืด โดยสารออกฤทธิ์นี้มีความสามารถในการปกป้องเซลล์ประสาทชนิด HT-22 จากภาวะเครียดออกซิเดชันและเป็นปัจจัยสำคัญทำให้สารสกัดจากใบรางจืดมีความสามารถลดการตายของเซลล์ประสาทผ่านวิถีออโตฟาจีได้ ซึ่งอาจสามารถนำไปพัฒนาเป็นสมุนไพรทางเลือกหรือยาเพื่อใช้ในการป้องกันหรือรักษาการเกิดโรคความเสื่อมของระบบประสาทได้ในอนาคต


Knob-Socket Investigation Of Stability And Specificity In Alpha-Helical Secondary And Quaternary Packing Structure, Taylor Renee Rabara 2019 University of the Pacific

Knob-Socket Investigation Of Stability And Specificity In Alpha-Helical Secondary And Quaternary Packing Structure, Taylor Renee Rabara

University of the Pacific Theses and Dissertations

The novel knob-socket (KS) model provides a construct to interpret and analyze the direct contributions of amino acid residues to the stability in α-helical protein structures. Based on residue preferences derived from a set of protein structures, the KS construct characterizes intra- and inter-helical packing into regular patterns of simple motifs. The KS model was used in the de novo design of an α-helical homodimer, KSα1.1. Using site-directed mutagenesis, KSα1.1 point mutants were designed to selectively increase and decrease stability by relating KS propensities with changes to α-helical structure. This study suggests that the sockets from the KS Model can …


Functional Analysis Of Bacillus Anthracis Aspartate Transcarbamoylase And Dihydroorotase, Katelyn Leigh Schwager Silva 2019 Wayne State University

Functional Analysis Of Bacillus Anthracis Aspartate Transcarbamoylase And Dihydroorotase, Katelyn Leigh Schwager Silva

Wayne State University Theses

There are many enzymes required for efficient and proper pyrimidine biosynthesis. The two that are most important and were discussed in this thesis are aspartate transcarbamoylase (ATCase) and dihydroorotase (DHOase). Both play an important role in not only pyrimidine biosynthesis production, but also mechanistic regulation of de novo synthesis. Anthrax is an infection caused by Bacillus anthracis. Here we studied ATCase and DHOase in Bacillus Anthracis. In this thesis we understood the effects of the enzymes ATCase and DHOase on pyrimidine biosynthesis. Adequate inhibitors of these enzymes would result in cell death and could pose as a cure to infection …


Eralpha Isoforms Modulate The Tumorigenicity Of 24r,25(Oh)2d3 In Estrogen-Responsive Cancer, Anjali Verma 2019 Virginia Commonwealth University

Eralpha Isoforms Modulate The Tumorigenicity Of 24r,25(Oh)2d3 In Estrogen-Responsive Cancer, Anjali Verma

Theses and Dissertations

Over 200,000 cases of breast cancer are diagnosed every year. Nearly 20% of these patients supplement their diets with some form of vitamin D. This high frequency of vitamin D supplement use may be due in part to research suggesting that cancer patients with higher serum vitamin D3 levels have better prognoses than patients with low serum vitamin D3. However, double-blind clinical trials on the efficacy of vitamin D3 supplementation in breast cancer have been inconclusive. A recent meta-analysis showed evidence of reduced cancer recurrence in patients taking vitamin D3 supplements who had ‘estrogen receptor positive’ …


Cyclophilin A As A Molecular Switch Regulating Prolactin Receptor Mediated Signaling, Mammary Tumorigenesis And Metastasis, Shawn Hakim 2019 Virginia Commonwealth University

Cyclophilin A As A Molecular Switch Regulating Prolactin Receptor Mediated Signaling, Mammary Tumorigenesis And Metastasis, Shawn Hakim

Theses and Dissertations

Prolactin (PRL) and its receptor (PRLr) have been implicated in the development and progression of human breast cancer. PRL activates its receptor and induces activation of proximal Janus kinase 2 (Jak2) for signal transduction. Here, we sought to determine the role of PRLr-associated peptidyl-prolyl isomerase, cyclophilin A (CypA), in modulating structure/function relationships of the PRLr. It was demonstrated that CypA mediated PRL-induced conformational change of the CFP- and -YFP tagged forms of the PRLr cytoplasmic-tail, whereas CypA inhibition by NIM811 (N-methyl-4-isoleucine cyclosporin) or knockdown blocked the conformational change of the PRLr assessed by Fluorescence Resonance Energy Transfer (FRET) signal or …


Preconditioning Of The Tumor Microenvironment By Means Of Low Dose Chemotherapies For An Effective Immunotherapy Of Breast Cancer, HUSSEIN F. AQBI 2019 Virginia Commonwealth University

Preconditioning Of The Tumor Microenvironment By Means Of Low Dose Chemotherapies For An Effective Immunotherapy Of Breast Cancer, Hussein F. Aqbi

Theses and Dissertations

Breast cancer mortality is mainly due to distant recurrence of the disease arising from dormant tumor cells established by cancer therapies. Patients who initially respond to cancer therapies often succumb to distant recurrence of the disease. It is not clear why people with the same type of breast cancer respond to treatments differently; some escape from dormancy and relapse earlier than others. In addition, some tumor clones respond to immunotherapy while others do not. We investigated how autophagy plays a role in accelerating or delaying recurrence of neu overexpressing mouse mammary carcinoma (MMC) following adriamycin (ADR) treatment, and in affecting …


Electrostatic Networks And Mechanisms Of Δph-Dependent Gating In The Human Voltage-Gated Proton Channel Hv1, Ashley L. Bennett 2019 Virginia Commonwealth University

Electrostatic Networks And Mechanisms Of Δph-Dependent Gating In The Human Voltage-Gated Proton Channel Hv1, Ashley L. Bennett

Theses and Dissertations

The structure of the voltage-gated proton (H+) channel Hv1 is homologous to the voltage sensor domain (VSD) of tetrameric voltage-gated Na+, K+ and Ca2+ channels (VGCs), but lacks a pore domain and instead forms a homodimer. Similar to other VSD proteins, Hv1 is gated by changes in membrane potential (V), but unlike VGCs, voltage-dependent gating in Hv1 is modulated by changes in the transmembrane pH gradient (DpH = pHo - pHi). In Hv1, pHo or pHi changes shift the open probability (POPEN)-V relation by ~40 mV per …


Targeting Sphingosine Kinase 2 As A Treatment For Cholangiocarcinoma, Anthony D. Stillman 2019 Human and Molecular Genetics

Targeting Sphingosine Kinase 2 As A Treatment For Cholangiocarcinoma, Anthony D. Stillman

Theses and Dissertations

Cholangiocarcinoma (CCA) has a high mortality rate and its occurrence is rising. This increase prompts the need for improved CCA treatments. Studies have suggested that CCA is highly reliant on the sphingosine-1-phosphate-receptor-2 (S1PR2) and sphingosine kinase 2 (SphK2). Recently, a competitive SphK2 inhibitor, ABC294640, has been approved for clinical trial. ABC294640 has the potential to treat CCA, which is support by a phase I clinical study that was able to temporarily treat a patient suffering from metastasized CCA with ABC294640. To determine the viability of ABC294640 as a treatment for CCA, this study focused on determining the effects of ABC294640 …


An Investigation On The Role Of Β-Arrestin 2, Protein Kinase C And Sex On The Mechanism Of Morphine Tolerance In The Mouse Ileum, Karan Hitesh Muchhala 2019 Virginia Commonwealth University

An Investigation On The Role Of Β-Arrestin 2, Protein Kinase C And Sex On The Mechanism Of Morphine Tolerance In The Mouse Ileum, Karan Hitesh Muchhala

Theses and Dissertations

Opioids such as morphine are frequently used in the clinic to treat pain. However, the perennial bane of chronic opioid use is the rapid development of tolerance to the analgesic effects but delayed development of tolerance to the respiratory depressant and constipating effects. As constipation is one of the most common opioid-related adverse effects in humans, it is important to delineate mechanisms that drive opioid tolerance in the ileum and lack of it in the colon. The overarching goal of this thesis was to investigate mechanisms of morphine tolerance in the ileum by comparing the mechanism of morphine tolerance in …


Stat5b And Stat5 Tetramers Are Essential For Ige-Mediated Mast Cell Function, Kasalina N. Kiwanuka 2019 Virginia Commonwealth University

Stat5b And Stat5 Tetramers Are Essential For Ige-Mediated Mast Cell Function, Kasalina N. Kiwanuka

Theses and Dissertations

Signal Transducers and Activators of Transcription (STATs) are latent transcription factors that mediate several cellular responses. This protein family consists of seven members, STAT1 – 6 including two closely related molecules, STAT5a and STAT5b, that show 96% amino acid sequence homology and are critical for lymphoid, myeloid and erythroid cell development and function. Activated STAT proteins dimerize and translocate to the nucleus, where they bind to high-affinity DNA motifs to modulate gene expression. We recently identified STAT5b as the critical regulator of IgE-mediated cytokine production in mast cells. STAT5b knockout (KO) cells show decreased sensitivity to IgE-mediated passive systemic anaphylaxis …


Adaptation Of The Streptococcal Collagen-Like Protein 1, Scl1, Of Group A Streptococcus To Recognize Fibronectin Type Iii Repeats, Dudley H. Mcnitt 2019 West Virginia University

Adaptation Of The Streptococcal Collagen-Like Protein 1, Scl1, Of Group A Streptococcus To Recognize Fibronectin Type Iii Repeats, Dudley H. Mcnitt

Graduate Theses, Dissertations, and Problem Reports (ETD)

Background: Group A Streptococcus (GAS) is responsible more than 700 million infections worldwide each year. Most of these infections start with initial colonization of the throat and skin, which is augmented by surface adhesins. The streptococcal collagen-like protein 1 (Scl1) is a major adhesin expressed by GAS that contains an N-terminal sequence-variable (V) domain, protruded away from the cell surface by the collagen domain. The Scl-V domain is comprised of three pairs of anti-parallel α-helices interconnected by surface-exposed loops. For attachment, GAS adhesins require a portal of entry, such as a wound or breach in the epithelium, to enter …


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