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The Effects Of Dietary Probiotic Inclusion On Skeletal Health Of Poultry And Its Possible Mechanisms, Feifei Yan Dec 2016

The Effects Of Dietary Probiotic Inclusion On Skeletal Health Of Poultry And Its Possible Mechanisms, Feifei Yan

Open Access Dissertations

Probiotics are live microorganisms which may confer health benefits on the host when administered in appropriate amounts. Numerous studies have shown that probiotics improve bone health in humans and rodents with less information available on the skeletal health of avians given probiotics. The objective of this study was to determine the effects of probiotic supplementation on bone health of egg-laying and meat-type chickens. Dietary supplementation of a multi-species based probiotic reduced the percentage of shell-less eggs beginning at 4 wk following treatment and increased tibial and femoral bone mineral density in egg-laying hens at 7 wk post-treatment. Similarly, bone mineralization …


Repurposing Non-Antimicrobial Drugs To Treat Multi-Drug Resistant Bacterial And Fungal Infections, Shankar Thangamani Dec 2016

Repurposing Non-Antimicrobial Drugs To Treat Multi-Drug Resistant Bacterial And Fungal Infections, Shankar Thangamani

Open Access Dissertations

Bacterial and fungal resistance to conventional antimicrobials is a burgeoning global health epidemic that necessitates urgent action. Even more alarming, the development of new antimicrobials to treat these multidrug-resistant pathogens has not kept pace with the rapid emergence of resistance to current antimicrobials. Antimicrobial drug development through the traditional de novo process is a risky venture given the significant financial and time investment required by researchers and limited success rate of translating these compounds to the clinical setting. This has led researchers to mine existing libraries of clinical molecules in order to repurpose old drugs for new applications (as antimicrobials). …


Immunotherapeutic Strategies To Reverse Tumor Associated Immunosuppression In Breast Cancer, Sruthi Ravindranathan Dec 2016

Immunotherapeutic Strategies To Reverse Tumor Associated Immunosuppression In Breast Cancer, Sruthi Ravindranathan

Graduate Theses and Dissertations

Heterogenous cancers such as breast carcinoma, would highly benefit from personalized vaccine approaches such as autologous tumor cell vaccines (ATCVs). By using cancer cells that are isolated from self, this approach has the potential to generate a polyclonal immune response against tumor antigens, that are specific to the individual. However, so far, ATCVs against breast cancers have not had any clinical success due to the poor immunogenicity of the malignant cells.

In this study, for the first time, we determined tumor derived G-CSF to play a major role in affecting immune response against breast cancer ATCVs. By using CRISPR/Cas9 genome …


Phenotypic Analysis And Localization Of Leukocytes At The Site Of Intradermal Injection Of Phytohemagglutinin In Chickens, Kallie Alyce Sullivan Dec 2016

Phenotypic Analysis And Localization Of Leukocytes At The Site Of Intradermal Injection Of Phytohemagglutinin In Chickens, Kallie Alyce Sullivan

Graduate Theses and Dissertations

Phytohemagglutinin (PHA) is commonly used to gain insight into an individual’s cellular immuno-competence. PHA is typically injected intradermally (i.d.) into the skin (e.g. wing web) and the tissue swelling response is then monitored, whereby the extent of the swelling positively relates to the individual’s cellular immune system capabilities. Although i.d. injected PHA was shown to stimulate mononuclear cell- and basophil-infiltration to the site of injection, reports on temporal, qualitative and quantitative aspects of the local PHA response are limited. The objective of this study was to use the growing feather (GF) as a cutaneous test-site to assess and monitor the …


Innate Immunity In Chickens: In Vivo Responses To Different Pathogen Associated Molecular Patterns, Kristen Alicia Byrne Aug 2016

Innate Immunity In Chickens: In Vivo Responses To Different Pathogen Associated Molecular Patterns, Kristen Alicia Byrne

Graduate Theses and Dissertations

Pattern recognition receptors (PRRs) on host cells recognize motifs known as pathogen associated molecular patterns (PAMPs) that are common to groups of microbes. Examples include LPS on Gram-negative bacteria, the structural motif PGN common to all bacteria, MDP the smallest immunostimulatory unit of PGN, and poly I:C the dsRNA analog. PAMP recognition by and stimulation of the innate immune system is crucial to an individual’s ability to quickly limit microbial growth and stimulate the adaptive immune system. Characterization of the in vivo immune responses initiated by PAMPs has not been directly addressed. Using growing feathers (GF) as a novel intradermal …


Identification Of Biomarkers Associated With Rous Sarcoma Virus-Induced Tumors In Two Divergently Selected Chicken Lines, Ashley Hayden Aug 2016

Identification Of Biomarkers Associated With Rous Sarcoma Virus-Induced Tumors In Two Divergently Selected Chicken Lines, Ashley Hayden

Graduate Theses and Dissertations

Poultry has become especially important to genetic research due to breeding feasibility, short generation turnover, and ease of maintaining large populations. The discovery of virus induced cancer has paved the way for further genetic studies. Rous Sarcoma Virus (RSV) is a tumor-causing virus that infects poultry. While not prevalent today, it can serve as a model for virus-induced cancer in humans and create additional insight to marker assisted selection in poultry. Genetically selected Arkansas Progressor (AP) and Arkansas Regressor (AR) chicken lines have been established and maintained at the Arkansas Experimental Station (AES) in Fayetteville, AR. Previous research has investigated …


Immune Modulating Functions By Soypeptide Lunasin In Cancer Immunotherapy, Chun-Yu Tung May 2016

Immune Modulating Functions By Soypeptide Lunasin In Cancer Immunotherapy, Chun-Yu Tung

Open Access Dissertations

Chemotherapy is currently the mainstay of treatment for most cancer patients. Despite its efficacy in eliminating cancer cells, a high percentage of chemotherapy patients eventually relapse or suffer progression of the disease. Immunosurveillance is capable of recognizing and eliminating continuously arising transformed mutant cells, and thus cancer immunotherapy is one of the emerging therapeutic strategies that harnesses the power of the immune system to eradicate chemotherapy-resistant cancerous cells. However, the adverse side effects of chemotherapy impede the therapeutic effects of immunotherapy. Our previous studies demonstrate that lymphoma patients are refractory to clinical immunotherapy because of chemotherapy-induced immune dysfunction. In addition, …


Proteomic Characterization Of Eggshell Membranes And Their Effect On Poultry Physiology And Immunity, Sarbjeet Kaur Makkar May 2016

Proteomic Characterization Of Eggshell Membranes And Their Effect On Poultry Physiology And Immunity, Sarbjeet Kaur Makkar

Graduate Theses and Dissertations

The use of antibiotics in poultry growth and disease control has led to antibiotics resistant problem in human beings, which is a big concern among consumers. With the necessity for judicious use of antibiotics in poultry production, alternative strategies to improve disease resistance in poultry production are necessary. The research is more inclined towards using the natural products available to grow healthier and antibiotic free meat animals. In the context of exploring natural and sustainable resource of alternative to antibiotics, the biochemical milieu of eggshell membranes (ESM) were analyzed by using mass spectrometry techniques including matrix assisted laser desorption ionization …


Comparison Of Different Modulators That Affect Macrophage Activation In Vitro, Alda Alexa Díaz Pérez Jul 2015

Comparison Of Different Modulators That Affect Macrophage Activation In Vitro, Alda Alexa Díaz Pérez

Graduate Theses and Dissertations

Inflammation is known as a mechanism to regulate and control infections as well as promote tissue repair. Macrophages (Mф) are known to be a major cell type in the initiation, sustainability and resolution of inflammation. Moreover, Mф are essential for the remodeling process that is also known as the wound healing response. The objective of this research was to compare five modulators (acetylsalicylic acid (ASA), dexamethasone (DEX), prostaglandin E2 (PGE2), iloprost, and resolvin D1 (RvD1) for their anti-inflammatory effects on macrophages in vitro. Then, Mф phenotype in terms of gene expression and secreted cytokine response was determined. Our study compared …


Development Of Novel Antifungal Peptides Based On A Natural Model Of Histatin-5 Peptide, Duy Tu Nguyen Dec 2013

Development Of Novel Antifungal Peptides Based On A Natural Model Of Histatin-5 Peptide, Duy Tu Nguyen

Graduate Theses and Dissertations

Our research group is working toward the development of novel antifungal peptides based on a natural model of peptide histatin-5. Histatin-5 is found in human saliva and known to protect our body against oral infections by Candida species. Candidiasis, or an infection caused by Candida species, is considered one of the most medically important fungal infections worldwide. Blood stream infections caused by Candida species are the fourth leading cause of hospital-acquired fungal infections that is associated with high mortality rates and high costs of treatment. This study investigated the modes of action of histatin-5 with the use of one 16-mer …


Role Of Mitogen-Activated Kinases In Cd40-Mediated T Cell Activation Of Monocyte/Macrophage And Vascular Smooth Muscle Cell Cytokine/Chemokine Production, Denise M. Milhorn Aug 1999

Role Of Mitogen-Activated Kinases In Cd40-Mediated T Cell Activation Of Monocyte/Macrophage And Vascular Smooth Muscle Cell Cytokine/Chemokine Production, Denise M. Milhorn

Electronic Theses and Dissertations

This dissertation represents efforts to determine the functional consequences acquired by vascular smooth muscle cells (SMC) in response to CD40 ligation by activated CD154+ T cells, and to elucidate components of the signaling pathway(s) activated in response to CD40 signaling in both monocytes and SMC. To study the consequences of CD40 stimulation, primary human monocytes and aortic SMC were treated with plasma membranes purified from CD154 + , CD4+ T cells. The results presented in this dissertation demonstrate that SMC, like monocytes/macrophages, are capable of interacting with T cells in a manner that results in reciprocal activation events. SMC were …


Tnf(Alpha)-Dependent And Tnf(Alpha)-Independent Activation Of Macrophage Effector Function, Annette R. Clemons-Miller May 1998

Tnf(Alpha)-Dependent And Tnf(Alpha)-Independent Activation Of Macrophage Effector Function, Annette R. Clemons-Miller

Electronic Theses and Dissertations

Tumor necrosis factor α (TNFα) is a pleiotropic cytokine that is predominantly produced by activated macrophages. The effects of TNFα are as diverse as the cells with which it interacts, e.g., stimulating fibroblast growth, exerting cytotoxic/cytostatic; activity against various human and murine cell lines, promoting inflammation through upregulation of endothelial adhesion molecules and IL-8 production. Yet TNFα is best known, and in fact was originally described, for its role in the bacterial-induced hemorrhagic necrosis of tumors and exacerbation of septic shock in which aberrant TNFα production leads to vascular collapse, cachexia, multiple organ failure, and ultimately death in as many …


Cd40-Mediated Signaling Of Interleukin-1(Beta) Synthesis And Rescue From Apoptosis In Monocytes: Modulation By Il-4 And Il-10, Jonathan C. Poe Dec 1997

Cd40-Mediated Signaling Of Interleukin-1(Beta) Synthesis And Rescue From Apoptosis In Monocytes: Modulation By Il-4 And Il-10, Jonathan C. Poe

Electronic Theses and Dissertations

To date, the cellular mechanisms involved in the progression of diseases characterized by chronic inflammation, such as rheumatoid arthritis (RA), remain largely unknown. However, cell-to-cell contact interactions between CD4+ helper T (Th) cells and monocytes have been implicated in the induction and maintenance of pro-inflammatory cytokine synthesis that is characteristic to the pathogenesis of RA. One such cytokine produced during monocyte-Th cell contact is interleukin (IL)-1 β, a mediator directly involved in the characteristic tissue destruction that occurs in the synovia of individuals with RA. Previous studies in our laboratories have shown that ligation of CD40 on monocytes with CD40 …


Role Of The Cd40-Cd40 Ligand Interaction In Cd4(+) T Cell Activation Of Monocyte Interleukin-1 Synthesis, David H. Wagner Dec 1994

Role Of The Cd40-Cd40 Ligand Interaction In Cd4(+) T Cell Activation Of Monocyte Interleukin-1 Synthesis, David H. Wagner

Electronic Theses and Dissertations

Most studies of the induction of cytokine synthesis in monocytes have used an exogenous triggering agent such as Lipolpoysaccharide (LPS). However, during nonseptic chronic inflammatory responses (e.g., rheumatoid arthritis) monocyte activation occurs as a result of T cell generated signals. This report demonstrated that plasma membranes from anti-CD3 activated peripheral CD4$\sp{+}$ T cells (Tm$\sp{\rm A}$) but not from resting CD4$\sp{+}$ cells (Tm$\sp{\rm R}$) induced monocytes to synthesize IL-1 in the absence of costimulatory cytokines. The expression kinetics of the molecule(s) unique to activated T cells which interact with monocyte receptors to induce IL-1 demonstrated that optimal expression occurred at 6h …


Nitric Oxide Production: A Mechanism For Inhibition Of Chlamydia Trachomatis Replication, Bojun Chen Dec 1993

Nitric Oxide Production: A Mechanism For Inhibition Of Chlamydia Trachomatis Replication, Bojun Chen

Electronic Theses and Dissertations

Chlamydia trachomatis (CT) replicates in macrophages, but is inhibited by IFN-$\gamma$ or LPS. IFN-$\gamma$ and/or LPS induced nitrite production in mouse peritoneal macrophages, macrophage cell lines (RAW264.7 and J774A.1) and McCoy cells. Kinetic studies indicated that peak production occurred 48 hours post-treatment. CT infection itself was insufficient to induce nitrite production, but resulted in enhancement of nitrite production in IFN-$\gamma$-treated cells. Treatment with IFN-$\gamma$ or LPS resulted in significant inhibition of CT replication in these cells. Strong correlation between nitrite production and inhibition of CT replication was observed in RAW264.7 and J774A.1 cells (correlation coefficients: $-$0.93 and $-$0.94, p $<$ 0.001). N$\sp{\rm g}$- monomethyl-L-arginine (L-NMMA) specifically inhibited nitrite production and partially reversed inhibition of CT replication in macrophage cell lines. NOS mRNA was measured in RAW264.7 cells by Northern blot and Dot blot hybridization. Strong correlation between NOS mRNA expression and inhibition of CT replication (correlation coefficient: $-$0.97, p $<$ 0.05) was observed. Anti-TNF-$\alpha$ antibody completely neutralized the biological activity of TNF-$\alpha$ secreted by LPS-treated RAW264.7 cells, yet the antibody neither reduced nitrite production nor restored CT replication. Combination of the antibody and L-NMMA significantly enhanced restoration of CT replication. In peritoneal macrophages, inhibition of CT replication induced by IFN-$\gamma$ was partially restored by L-NMMA or anti-TNF-$\alpha$ antibody. In McCoy cells, inhibition of CT replication induced by IFN-$\gamma$ and LPS was not significantly restored by L-NMMA. Great restoration of CT replication by 1 mM L-NMMA was observed in LPS-treated J774A.1 cells (31%), but not in IFN-$\gamma$-treated cells (5%). Our data indicate that (1) NO production is one of the mechanisms for inhibition of CT replication in IFN-$\gamma$-activated peritoneal macrophages and RAW264.7 cells; (2) NO plays a significant role in CT inhibition in LPS-treated macrophage cell lines, but not peritoneal macrophages; (3) TNF-$\alpha$ may be associated with inhibition, but the mechanism(s) may not involve NO production; (4) NO production may not be the mechanism for CT inhibition in McCoy cells treated with IFN-$\gamma$ and LPS.


Mechanisms Of T Cell-Mediated Macrophage Activation: Role Of Antigen Specific And Antigen Nonspecific Cognate Interactions, Xiang Tao Jun 1993

Mechanisms Of T Cell-Mediated Macrophage Activation: Role Of Antigen Specific And Antigen Nonspecific Cognate Interactions, Xiang Tao

Electronic Theses and Dissertations

Macrophages play an important role in host antimicrobial immunity and in non-septic inflammatory reactions. Most studies on macrophage activation have focused on the roles of the T cell-produced cytokine, interferon-$\gamma$ (IFN$\gamma)$ and bacterial product, lipopolysaccharide (LPS). T cell-macrophage interaction is a critical step in initiating both specific and nonspecific immune responses to antigenic stimulation. The current study examines the role of cognate T cell-macrophage interaction in activation of macrophage effector functions and induction of macrophage early activation gene expression. Viable resting T$\sb{\rm H}$2 clone cells can activate IFN$\gamma$-primed macrophages to produce reactive nitrogen intermediates (RNI) or express cytostatic activity. The …


Probing Protein-Protein Interactions Among Proteins Of A Nonaggregated Fatty Acid Synthetase From Euglena Gracilis Variety Bacillaris, Sande G. Williams May 1993

Probing Protein-Protein Interactions Among Proteins Of A Nonaggregated Fatty Acid Synthetase From Euglena Gracilis Variety Bacillaris, Sande G. Williams

Electronic Theses and Dissertations

Enoyl-acyl carrier protein (ACP) reductase from chloroplast nonaggregated fatty acid synthetase (FAS) of Euglena gracilis variety bacillaris was purified to a single band on a denaturing polyacrylamide gel. The enzyme was partially characterized with respect to substrate specificity, reduced nucleotide requirement, and the effect of ACP and Ca$\sp{++}$ on enzyme activity. Antibodies against the purified protein were raised in hens and isolated from eggs. ACP was purified from Euglena in yields of about 1mg/100g (wet weight) of cells. Antibodies were raised against the purified protein. ACP antibodies inhibited the Euglena chloroplast FAS using Euglena or E. coli ACP as a …


Generation, Isolation And Assay Methods For Human Lymphocyte Mitogenic Factor, Thomas E. Seay Dec 1982

Generation, Isolation And Assay Methods For Human Lymphocyte Mitogenic Factor, Thomas E. Seay

Electronic Theses and Dissertations

Activated lymphocytes secrete many products including the lymphokine human lymphocyte mitogenic factor (HLMF). In preliminary experiments lymphocytes from peripheral blood and palatine tonsils were evaluated as possible sources of HLMF by evaluating their level of activation through screening their spontaneous and concanavalin A (con A)-induced blastogenic responses. Tonsil lymphocytes (TL) were found to have high spontaneous proliferation as compared to peripheral blood lymphocytes (PBL). Cells from both sources responded to con A by undergoing a typical blastogenic response. Because TL must be obtained septically, they are frequently cultured in the presence of the antimycotic agent, Amphotericin B (Am B). Since …


Tonsil Cell Products Which Modify In Vitro Proliferation Of Blood Lymphocytes, Thomas W. Hodge May 1982

Tonsil Cell Products Which Modify In Vitro Proliferation Of Blood Lymphocytes, Thomas W. Hodge

Electronic Theses and Dissertations

Human palatine tonsil lymphocytes, when compared to peripheral blood lymphocytes (PBL), were in an activated state even though there was no in vitro stimulation. When these tonsil lymphocytes were cultured in the absence of serum and polyclonal mitogens or antigens, the supernatant fluid often inhibited the proliferative response of target PBL to con A. The extent of this suppression ranged from 22% to 84%, and target cell viability was 90% or greater. There was no evidence for the presence of immunoglobulins or (alpha)2-macroglobulin in whole supernatant fluids. The suppressor was partially denatured at 80(DEGREES)C and was rendered completely inactive upon …