Now showing items 41-60 of 93

    • Characterization of 5HT1B and 5HT7 using Bioluminescence Resonance Energy Transfer

      Adams, Elizabeth; Department of Chemistry and Physics (Augusta University, 2019-05)
      GPCRs play a major role in cell signaling through their interactions with heterotrimeric G proteins. In conventional models of GPCR-G protein coupling, agonist binding promotes a conformational change within the receptor, which then associates with G proteins, facilitating the exchange of GDP for GTP. GTP-bound G proteins dissociate from the receptor and exert their effects on downstream signaling molecules. Previous studies suggest that serotonin 5HT7 receptors associate with Gs heterotrimers prior to agonist binding, and that 5HT7-Gs complexes dissociate after the G protein is activated. Here we study this unconventional mode of coupling using bioluminescence resonance energy transfer (BRET) between luciferase-tagged 5HT7 receptors and Gs heterotrimers labeled with Venus. Our results confirm that 5HT7 receptors interact with inactive (GDP-bound) Gs heterotrimers in the absence of an agonist, and that this interaction is stabilized by the inverse agonist methiothepin. Stimulation with the endogenous agonist serotonin (5HT) decreased BRET between 5HT7 receptors and Gs, indicating that the activation of the receptor leads to 5HT7-Gscomplex dissociation. Interestingly, Gs activation was not required for complex dissociation. These results are consistent with the hypothesis that 5HT7 receptors couple to Gs heterotrimers via an unconventional mechanism involving ligand-sensitive complexes of receptors and inactive Gs.
    • Effects of Vitamin D Receptor Knockout, Vitamin D Deficiency, and Diabetes on Corneal Epithelial Nerve Density

      Vick, Sarah; Department of Biological Sciences (Augusta University, 2018-12)
      This project is designed to test the hypothesis that vitamin D deficiency exacerbates preexisting primary corneal pathologies. Our lab has established that the corneal epithelium in diabetic mice heals at a faster rate than the epithelium in diabetic vitamin D receptor (VDR) knockout (KO) mice. It is known that within diabetic mice, the corneal nerve density is decreased, and it has been hypothesized that the decreased nerve density can slow corneal epithelium healing within mice. However, it is unknown how VDR KO or vitamin D deficiency in diabetic mice will affect corneal nerve density. In order to determine if nerve density is affected by VDR KO or vitamin D deficiency, mouse corneas were collected, nerves were immuno-stained for confocal microscope photography, and images were analyzed by image processing to determine nerve density. The results demonstrate that in otherwise healthy vitamin D deficient and VDR KO mice lacking the diabetic condition, nerve density was not affected by either vitamin D condition. Corneal nerve density was significantly decreased when vitamin D deficiency or VDR KO was combined with diabetes, confirming the hypothesis that vitamin D deficiency does worsen preexisting corneal pathologies. In addition, this finding may provide an explanation as to why diabetic VDR KO mice have delayed epithelial wound healing compared to control diabetic mice.
    • Optimizing Isolation and Culture of Primary Microglia

      Doughty, Deanna; Department of Biological Sciences (Augusta University, 2018-12)
      Glioblastoma (GBM) is the most aggressive and common adult brain tumor subtype, with the majority of patients surviving less than one year. The GBM microenvironment is composed of tumor cells as well as non-cancerous cells, such as microglia, a component of the immune system in the brain. To better understand the role of microglia in GBM, we have optimized in vitroculture conditions for primary microglia. Growing microglia in culture is challenging, but this technique is needed for planned future experiments. Microglia were isolated from mouse neuronal tissue by magnetic bead antibody cell separation using the cellular marker CX3CR1. Isolated microglia were then cultured in various culture conditions, and cellular morphology by light microscopy was used to determine cell health, viability, and activation status. It was determined that the primary microglia grow best in neurobasal media in wells coated with poly-D lysine. Future studies aim to isolate a larger number of cells to allow forco-culture of the inactivated microglia with GBM cells. These results will allow us to better understand the role that microglia play in GBM progression.
    • Iron, Copper, Nickel, and Zink Ion Concentrations in Rae's Creek

      Bridgers, Aerial; Department of Chemistry and Physics (Augusta University, 2018-12)
      Heavy metals can enter water systems through a variety of methods, such as through soil run-off, rain, or industrial activity near the system. Many of these heavy metals are toxic to both the wildlife and people around the system if present in high enough concentrations. The aim of this research was to create a model for a local water system, Rae's Creek, outlining the concentrations of iron, copper, nickel, and zinc present throughout a seven-month period. Additionally, this research sought to pinpoint any correlation between increases in metal concentrations and outside events, such as rain or the Master's Tournament held yearly in Augusta. Results indicated that copper and zinc concentrations were well above guidelines set for recreational water quality by the Environmental Protection Agency, while iron and nickel concentrations were generally below the limitations set for their concentrations. While rain had no observed effect on the heavy metal concentrations, there are two specific dates where all four metals had a marked increase in concentration. However, it is inconclusive as to what caused this increase.
    • The Mechanism of Protein Kinase C in regulation of ATPase family AAA-domain Containing Protein 3A in Head and Neck Squamous Cell Carcinoma

      Chemmalakuzhy, Ron; Department of Biological Sciences (Augusta University, 2018-12)
      One of the most important challenges of cancer treatment is inhibition of the metastasis of head and neck squamous cell carcinoma (HNSCC). HNSCC is a form of squamous cell carcinoma (SCC) that is localized in the mucosa] linings of the nose, mouth, and throat areas. HNSCC has a mortality rate of 350,000 deaths per year and approximately 630,000 new patients are diagnosed annually. The ATPase family AAA-domain containing protein 3A (ATAD3A) is a nuclear-encoded mitochondrial enzyme that has been identified to be highly expressed and associated with poor survival in I-INSCC patients. ATAD3A is involved in various cellular processes including mitochondrial dynamics, cell growth, cholesterol metabolism, and communication between endoplasmic reticul um and mitochondria. Although ATAD3A has been shown to act as a crucial regulator promoting head and neck cancer cell invasion and metastasis, the precise mechanism by which ATAD3A is upregulated in HNSCC cells is largely unknown. In this study, we elucidate for the first time that Protein Kinase C (PKC) enhances tumor­ promoting activity in HNSCC cells through regulating ATAD3A expression levels. The study uncovers the biological effects of PKC regulation in HNSCC cells, providing a strong rational basis for the design of novel therapeutic regimens by inhibition of ATAD3A in order to eventually increase cure rate in patients diagnosed with HNSCC.
    • Method development and environmental sampling of AVM toxin

      Maron, Nicholas; Department of Biological Sciences (Augusta University, 2018-12)
      Hydrilla in Lake Thurmond is colonized by cyanobacteria linked to avian vacuolar myelinopathy (AVM), a disease affecting several avian species including bald eagles and American coots. The cyanobacteria produce a neurotoxin that causes brain lesions and adverse effects including the inability to fly, swim, and walk. Prior studies have established that the toxin can be ingested through the hydrilla, but this test aims to determine the presence of the cyanobacterial toxin in the water. An experiment was designed using an ENVITM SPE Disk (C18 bonded phase) that successfully extracted the toxin from a previously spiked water sample. Water samples were collected from the lake during the Fall 2016 AVM season and are currently being analyzed for the presence of the toxin with the previously developed SPE disk method. This study was developed in order to create a method to test the water samples for toxin, identify different routes of exposure to the toxin, and evaluate its environmental effects.
    • The Role of CXCL10 (IP 10) in Breast Cancer/ Stromal Macrophage Interactions

      Mikulsky, Emilee; Department of Biological Sciences (Augusta University, 2019-05)
      Breast cancer is the second most deadly cancer with more than 260,000 people being diagnosed, and over 40,900 dying from it annually in the United States. This project focuses on triple negative breast cancer (TNBC), which is very aggressive due to the lack of hormone receptors. TNBC is characterized by an expansive stromal compartment that contains a large percentage of immune system macrophages, which correlates with poor patient prognosis. The Bradford lab has identified that the chemokine CXCL10 was found to be decreased at the mRNA and protein levels in TNBC cells when co-cultured with macrophages. The loss of CXCL10 might result in less destruction of tumors. To better understand the decrease in CXCL10, a cell invasion assay investigating invasion ability of the MDA-MB231 TNBC cell line was completed using macrophage conditioned media, with and without recombinant CXCL10, or a CXCL10 neutralizing antibody. We also investigated whether the NF-kappaB signaling pathway was involved by using primary bone marrow-derived macrophages from a NF-kappaB knockout mouse. The cell invasion assay showed that altering CXCL10 and NF-kappaB signaling in macrophages and/or the MDA-MB231 cells leads to differences in invasion ability.
    • The Sublethal Effects and Bioaccumulation of 17-Ethinyl Estradiol in Lumbriculus variegatus

      Ogun-Semore, Kikelomo; Department of Biological Sciences (Augusta University, 2019-05)
      Freshwater sources are subject to contamination from toxic compounds and other harmful materials through improper sewage cleanup and pollution. Ethinyl estradiol (EE), a synthetic, steroidal estrogen used in contraception, is present in varying concentrations across freshwater sources worldwide. EE is also classified as an endocrine disruptor that is known to interfere with the endocrine system. Endocrine disruptors can create adverse effects on bodily systems and have been found to affect behavioral patterns, enzymatic activity levels, and estrogen receptor levels. Preceding data has found that EE exposure leads to an increase in mortality, a decrease in offspring, and changes in reproductive morphology among freshwater invertebrates. The objective of this study was to observe the sublethal effects and bioaccumulation of ethinyl estradiol in Lumbriculus variegatus. Data collection on experimental endpoints, including reproduction rate, segment regrowth of L. variegatus, have been collected. The bioaccumulation of EE within L. variegatus was observed through sediment testing and an ethinyl estradiol ELISA. The data collected from this experiment contributes to information available on the effects of low-dosage endocrine disruptor concentrations on freshwater organisms. The effects of EE and its bioaccumulation could be extrapolated to include bioaccumulation of EE in organisms of higher trophic levels, including vertebrates.
    • Vaccine Proliferation in the Face of Public Scrutiny

      Sripathi, Nishita; Department of Biological Sciences (Augusta University, 2019-05)
      Each newly conceptualized vaccine has faced the same arguments over the last two centuries. A detailed examination of these several vaccines and their influences on the public will hopefully provide a better understanding of why the same arguments against vaccines continuously come up, even though each vaccine becomes widely used and celebrated. I supported my analysis by examining modern vaccine case studies and how those results may or may not skew the public reaction. By focusing on these two areas of research, I tried to understand the reasons behind persisted vaccine apprehension, even though there have been multiple and well-supported conclusions that vaccines are essential to a healthy human population. Perhaps by understanding the public's fear, I can one day suggest alternate methods of vaccine roll out and introduction to the public.
    • The Role of Neddylation in Cardiac Fibrosis

      Srivatsa, Abhiram; Department of Biological Sciences (Augusta University, 2018-05)
    • An Analysis of the Economy of Greece

      Mack, Michaela; Department of Mathematics (Augusta University, 2018-05)
    • Structural, Kinetic and Functional Properties of Adenylyl Cyclase-Associated Protein 1 / Adenylyl Cyclase Complexes in Pancreatic Cancer Cells

      Mehrotra, Simran; Department of Biological Sciences (Augusta University, 2018-05)
      Of all the different cancers, pancreatic cancer is one of the major unsolved health problems. It is important to study the mechanism through which the pancreatic cells migrate to prolong survival in patients. Concerning the progression of pancreatic cancer, the adenylyl cyclase (AC)/adenosine 3,5 cyclic monophosphate (cyclic AMP) pathway has shown to inhibit in the migration of pancreatic cancer cells. Adenylyl cyclase- associated protein 1 (CAP1) is a protein that is involved in the regulation of actin microfilament formation, which ultimately leads to cell migration and invasion. The CAP 1 protein binds to G-actin, inhibiting polymerization which inhibits filopodia formation, inhibiting cell migration. In a previous research project in the lab it was found that CAP 1 reacts with different adenylyl cyclase (AC) isoforms: AC1, AC3, AC4 and AC7. behavior. The objective of this research was, through theoretical and experimental analyses, to determine to which extent CAP1 interacts with the 4 transmembrane AC isoforms mentioned above. Through a sequential co-immunoprecipitation approach, I determined which AC isoform experimentally has a higher affinity for CAP1 using the HPAC cell line, which is moderately differentiated. Based on the theoretical and experimental results, AC3 and AC4 have the highest affinity for CAP1.
    • Identifying candidates genes involved in syndromic and non-syndromic intellectual diability in consanguineous Pakistani families

      Brown, Jason; Department of Biological Sciences (Augusta University, 2018-05)
      Intellectual disability (ID) is characterized by substantial limitations in intellectual functioningbefore the age of 18. One of its causes is genetic etiology. Around 300 genesarebelieved to beinvolved in autosomal recessive ID (ARID). It is thought that there are still many more genes as yet undiscovered. Consanguineous families have higher rates of autosomal recessive disorders and so make a good population in which to study ARID. Phenol-chloroform extraction was performed on the bloodof five consanguineous Pakistani families with syndromic and non-syndromic ID to obtain DNA. The DNA wasgenotyped using an SNP microarray and homozygosity mapping was used to analyze the genotyping data to provide candidate regions within the chromosomes likely to contain genes involved in ID. A review of current literaturewasperformed to identify the most likely candidate genes among the identified regions in each family. In the most likely region from each family, 36 genes in total were identified as candidates for involvement with ID, with 17 identified as stronger candidates. This paves the way for future studies to provide more evidence for causation. DNA sequencing could be used to identify potentially causative mutations, which could then be tested in animal models.
    • You Really Are Too Kind: Implications Regarding Friendly Submissiveness in Trainee Therapists

      Cain, Lylli; Department of Psychological Sciences; Augusta University (4/20/2018)
      To facilitate patient growth, therapists must immerse themselves in the patient’s world while also being able to see what is needed for change. This process requires finding a delicate balance between supporting and pushing patients. Therapists in training are additionally tasked with incorporating supervisors’ suggestions with their own views on what is needed to help their patients. Beginning therapists with tendencies to be overly accommodating may struggle to reconcile these competing demands. Thus, the aim of the present work is to explore how trainee friendly submissiveness (FS) interfaces with psychotherapy. Prior to training, clinical graduate trainee (n = 35) FS was assessed using the Inventory of Interpersonal Problems-32. Process and outcome data were then collected from each therapist’s first training case. Specifically, each trainee was assigned an undergraduate student volunteer with whom they had four non-manualized therapy sessions over the academic semester. After the third session, patients and trainees completed questionnaires assessing session impact and the working alliance, and two expert raters coded third session videotapes for techniques. Following termination, patients rated the overall helpfulness of the therapy. Trainee FS was significantly negatively associated with patient-rated depth, alliance, and overall helpfulness with moderate effects. Findings from a mediation analysis further suggested that trainees with high FS struggled to focus the therapy in a way that felt productive to patients. Implications for clinical training are discussed.
    • Investigation of the Effects of Leptin Treatment Towards AlphaAdrenergic Receptor Expression in Mouse Aortic, Renal, and Mesenteric Arteries and Adrenal Glands.

      Momtahan, Mina; Department of Biological Sciences (Augusta University, 2017-12)
      Body weight gain and obesity lead to an elevation in blood pressure (BP) also called hypertension when the level of blood pressure reaches 140 and 90 mmHg for the systolic and diastolic BP respectively. Previous work from this lab demonstrated that the adipocyte-derived hormone leptin, secreted in important amounts in obesity, reduces the ability of the aortic artery to contract in response to adrenergic stimulation, likely mediated by a decreased expression of the aorta alpha-adrenergic receptors. However, it is not known whether leptin decreases the expression of alpha-adrenergic receptors in other arteries such as the mesenteric and renal, as well as the adrenal glands that play a key role in the control of BP. To determine whether leptin decreases alpha-adrenergic receptors expression in these arteries, as it does in the aorta, we infused leptin (10ug/day) by implanting subcutaneous mini-pumps in a total of 10 male C57bl/6 mice and evaluated leptin-mediated changes via alpha-adrenergic receptor expression. Real-time PCR (qPCR) conducted on the arteries revealed fold changes which were not supportive of our hypothesis that leptin- mediated sympatho-activation decreases adrenergic receptor expression.
    • Exploring Music's Effects on Blood Pressure and Heart Rate Through Changes in Oxytocin Levels

      Cauthron, Steven; Department of Chemistry and Physics (Augusta University, 2017-12)
      High blood pressure and high heart rate can increase chances of a variety of diseases. This study looked at the impact of music on blood pressure and heart rate in pre-hypertensive individuals based on changes in their oxytocin levels. We hypothesized that listening to music would result in an increase in oxytocin and therefore a decrease in blood pressure and heart rate. This study involved 16 pre-hypertensive individuals. Hemodynamic measurements and oxytocin counts were obtained in three different experimental conditions: rest (control), stressed and after listening to music. The study results indicated a significant reduction in heart rate after listening to music. There was no significant change in blood pressure after listening to music. The results of this study show that listening to music is associated with higher oxytocin levels.
    • Anion Monitoring of Rae's Creek by Ion Chromatography

      Walton, Amberly; Department of Chemistry and Physics (Augusta University, 2018-12)
      Golf courses generally require large amounts of fertilizer to maintain their course appearance. Fertilizer is a source of phosphate- and nitrogen-based compounds. These compounds can have negative effects on aquatic life if there are large amounts introduced to the surface water. The effect of a golf course on anion concentrations in Rae’s Creek was studied using ion chromatography. Over the course of one year, the following anions were tracked: nitrate, nitrite, sulfate, phosphate, bromide, and chloride. The concentrations of the anions were high enough to allow quantitative measurements and changes were observed, but the concentrations remained below EPA guidelines for streams.