• The Role of RYBP in the Regulation of Apoptosis

      Novak, Rachel Lynn; Georgia Cancer Center (6/5/2014)
      The tumor suppressor Tp53 is the most frequently mutated gene in human cancer. Tp53 encodes a sequence specific transcription factor termed p53 that activates a number of biological programs contributing to tumor suppression, most notably, the promotion of cell cycle arrest and apoptosis. To identify new regulators of p53’s transcriptional activity, we performed a yeast 2-hyrbid screen and have identified Ring 1 YY1 Binding Protein (Rybp) as a novel p53-interacting partner. Consistent with its role as a transcriptional repressor, we have demonstrated that Rybp inhibits p53-mediated transcription. In addition, Rybp forms a trimeric complex with the critical negative regulator of p53, Mdm2. Mdm2 is an E3 ligase that ubiquitinates p53, targeting it for degradation, and expression of Rybp enhances the Mdm2-mediated ubiquitination. To further investigate the role of Rybp in the regulation of endogenous p53 stability we constructed a recombinant adenovirus expressing Rybp (Ad-Rybp). Ad-Rybp infection inhibited the accumulation of p53 and the induction of p53 target genes in response to genotoxic stress. However, interpretation of the results was confounded by Ad-Rybp infection reducing global mRNA levels. Despite inhibition of p53, Ad-Rybp was a powerful inducer of apoptosis, and we investigated this in more detail. Analysis of a panel of tumor cell and untransformed cell types revealed that Ad-Rybp infection specifically induces apoptosis in tumor cells but not in normal diploid cells. Furthermore, at a low multiplicity of infection, Ad-Rybp sensitizes tumor cells to apoptosis in the presence of the death receptor ligands, Tumor Necrosis Factor alpha (TNFα) and TNF related apoptosis inducing ligand (TRAIL). These results suggest that the tumor-specific killing properties of Rybp may be exploited for therapeutic advantage.
    • Evaluation of a Novel Compression Resistant Matrix for Recombinant Human Bone Morphogenetic Protein-2 (RHBMO-2) for Onlay Graft Indications

      Lu, Sheldon; Department of Oral Biology (6/4/2014)
      The discovery and subsequent characterization of endogenous signaling peptides known as bone morphogenetic proteins (BMPs) capable of inducing de novo bone formation in postfetal life represents a critical advancement in the understanding of tissue morphogenesis and has become an incentive to develop additional growth factor based tissue engineering strategies (Wozney & Seeherman 2004). Because BMPs act locally, a suitable carrier system must be used to ensure effective presentation of an adequate dose to a target site (Mont et al. 2004). A number of candidate biomaterials have thus been tested as potential carrier technologies (Huang et al. 2008). Currently, recombinant human BMP-2 (rhBMP-2) coupled with an absorbable collagen sponge (ACS) manufactured from bovine Achilles tendon Type 1 collagen is the only FDA approved device for orthopedic and craniofacial indications. Although the rhBMP-2/ACS construct has demonstrated clinical efficacy for indications including spine fusion, long bone fracture healing, sinus and alveolar augmentation, the ACS’s inability to resist tissue compression limits its use for onlay indications (Wikesjö et al. 2007).
    • Regulation of GluN2C-Containing N-methyl-D-aspartate (NMDA) Receptors

      Chung, Connie; Department of Neuroscience and Regenerative Medicine (6/3/2016)
      NMDA receptors (NMDARs) play a major role in the pathological events following excitotoxicity. Post-ischemic activation of NMDARs has been linked to opposing signaling that mediates pro-survival or pro-death activity. This dichotomy is largely due to distinct GluN2 subunit compositions governing important receptor functions including channel properties, receptor trafficking, and synaptic localization. Compared to GluN2A- and GluN2B-containing NMDARs, the trafficking of GluN2C in non-cerebellar granule neurons is less well understood. Moreover, the role of GluN2C following cerebral ischemia remains unknown. Here, we report 14-3-3 isoform-specific binding and regulation of GluN2C. Our findings highlight the isoform-specific structural and functional differences within the 14-3-3 family of proteins which determine GluN2C binding and its essential role in targeting the receptor to the cell surface to facilitate glutamatergic neurotransmission. Next, we sought to investigate the role of GluN2C following cerebral ischemia. We show that GluN2C expression promotes neuronal survival as a homeostatic mechanism by which intracellular Ca2+ levels are maintained by upregulation of GluN2C. Through such a mechanism, not only the intracellular Ca2+ level but also NMDAR signaling can be maintained at equilibrium.
    • Attenuating the Interaction Between Delta Protein Kinase C and the "d" Subunit of FIFo ATp Synthase Protects Against Cardiac Ischemia/Repferusion injury

      Walker, Matthew; Deparment of Pharmacology and Toxicology (6/3/2016)
      Cardiac ischemia / reperfusion (IR) injury most often results from the thrombotic blockade of the coronary arteries and is the most frequent cause of death in humans. Despite the significant role energy deprivation plays in cardiac IR injury, few studies have targeted the IR-induced impairment of the mitochondrial F1Fo ATP synthase. We have previously demonstrated delta protein kinase C (δPKC) involvement in cardiac myocyte energy deprivation via its interaction with the “d” subunit of F1Fo ATP synthase (dF1Fo) and have developed a peptide inhibitor [NH2YGRKKRQRRMLATRALSLIGKRAISTSVCAGRKLALKTIDWVSFDYKDDDDK- COOH] of this interaction. It targets to the mitochondrial matrix / inner membrane. The inhibitor peptide contains a FLAG epitope which allowed confirmation of its uptake into cardiac mitochondria. Our early studies in neonatal cardiac myocytes (NCMs) led us to the hypothesis that PKC inhibits ATP production in vivo via an interaction with dF1Fo to exacerbate cardiac IR injury. To directly test our hypothesis, we first utilized the Langendorff isolated heart model to show that PKC co-immunoprecipitates (co-IPs) with antisera to dF1Fo in myocardium exposed to simulated IR injury. Administration of the inhibitor peptide to the isolated rat hearts prior to cardiac IR attenuated the co-IP of 􀁇PKC with dF1Fo, improved recovery of contractility, diminished levels of tissue t-carbonyls and 4-hydroxy-2-nonenal (HNE), and reduced myocardial infarct size (as assessed by 2, 3, 5 triphenyltetrazolium chloride (TTC) staining) following simulated IR exposures. Additionally, this peptide enhanced ATP levels 2.1 fold, improved ADP-stimulated mitochondrial respiration, and attenuated Ca++-induced mitochondrial swelling in ischemic myocardium. We next evaluated the inhibitor peptide in an in situ rat coronary ligation model for its ability to protect live rats from cardiac IR injury. A 10 min coronary ligation increased the PKC-dF1Fo co-IP in the region at risk (RAR) by 5-fold which was attenuated by 71% with intravenous infusion of the inhibitor peptide. This response correlated with an enhancement of ATP levels, a 2-fold reduction in oxidative stress markers, improvement in systolic cardiac function, and a reduction in TTC monitored myocardial infarct size in the RAR. These results support further development of this peptide as a first-in-class-translational therapeutic for the treatment of cardiac IR injury.
    • Regulation and Function of the Major Stress-Induced HSP70 Molecular Chaperone in vivo: Analysis of Mice with Targeted Gene Disruption of the HSP70.1 or HSP70A1

      Huang, Lei; Georgia Cancer Center (6/3/2002)
      (First Paragraph) The cellular response to stress, including exposure to environmental (UV radiation, heat shock, heavy metals), pathological (infection, fever, inflammation, malignancy, ischemia) or physiological (growth factor, hormonal stimulation, tissue development) stimuli is represented at the molecular level by synthesis of groups of protein named heat shock proteins [hsp(s)] (Benjamin 1998; Feder and others 1992; Jolly and Morimoto 2000; Li and Mivechi 1986; Lindquist 1986; Smith 1998). The presence of hsp(s) protect host cells from the damage caused by thermal stress, and after induction of hsp expression, cells are protected well from higher temperatures than they can normally tolerate. This phenomenon is defined as themiotoleranee (Gemer 1975; Li and Mivechi 1986). The protective role of hsp(s) is attributed to several functional properties, including active participation in maintaining proteins in their native correctly folded states, promoting degradation and refolding of misfolded proteins, and minimizing aggregation and incorrect interactions between proteins (Agashe and Hartl 2000; Gething and Sambrook 1992). In addition, hsp(s) can function in cellular protection by modulating the engagement and progression of apoptosis induced by a variety of stress stimuli (Beere and Green 2001). Besides the recognition of the cytoprotective function of hsp(s) under stress conditions, widespread clinical interests exist in their chaperone function during a range of human pathologies, including neurodegenerative conditions, such as amyloidosis, prion disease, and Alzheimer's disease, and cardiovascular diseases, such as myocardial ischemia, cardiac hypertrophy, stroke, and blood vessel injury (Benjamin 1998; Planas and others 1997; Smith 1998).
    • Using peptide-based vaccines to enhance adoptive cell therapy with genetically engineered T cells

      Fan, Aaron; Department of Neuroscience and Regenerative Medicine (6/27/2018)
      Adoptive cell therapy (ACT) of retrovirally transduced (RV) CD8 T cells is a powerful technique that has shown promise in tumor eradication in cancer patients. However, some major barriers to current methods are that ACT is expensive, time consuming, and requires harmful and toxic adjunct procedures. The Celis laboratory has demonstrated the use of TriVax, a potent peptide vaccination strategy that dramatically expands ACT cell populations and bypasses the necessity for adjunct procedures. The purpose of my thesis project was to enhance current methods of ACT+TriVax by testing an antigen-specific antitumor response of RV CD8 T cells and if it could be improved with constitutively active STAT5 (CA-STAT5) expression, a protein activated downstream several cytokine pathways that have been shown to play a role in increasing CD8 T cell persistence and resistance to apoptosis. Here, I aimed to test the hypothesis that CA-STAT5 in CD8 T cells enhances an antitumor effect by increasing T cell persistence and efficacy. My results show that TriVax administration selectively expanded frequencies of the ACT cell population expressing gp100-TCR in both blood and spleen. When co-transduced with CA-STAT5, an even higher fold expansion of antigen-specific cells was observed. +CA-STAT5 T cells were able to expand more robustly than -CA-STAT5 T cells upon repeated antigen stimulation (vaccine boost), demonstrating nearly 4000-fold increases in antigen-specific CD8 T cells. +CA-STAT5 T cells also seemed to persist longer in vivo over time, and they expressed lower levels of surface PD-1. Using B16F10 melanoma, ACT+TriVax of these cell populations into tumor-bearing mice demonstrated a powerful antitumor effect, leading to tumor regression in treated groups. CA-STAT5 seemed to recapitulate similar antitumor effects our laboratory observed previously with combinatorial anti-PD-L1 treatment or IL2/anti-IL2 mAb complexes (IL2Cx), suggesting a potential role for STAT5 in resisting the PD-1/PD-L1 inhibitory pathway. Altogether, these results demonstrate that RV CD8 T cells expressing gp100-TCR and CA-STAT5 are capable of antigen-dependent expansion in response to TriVax. CA-STAT5 plays a role in increasing T cell proliferation and persistence, as well as increasing efficacy through resistance to PD-1/PD-L1 inhibition.
    • Exploration of Two Methodologies for Measuring Clinical Judgment in Baccalaureate Nursing Students.

      Call, Marlene W.; Department of Physiological and Technological Nursing (5/8/2017)
      Introduction: Senior nursing students need a requisite level of preparedness to safely care for an acutely ill, complex patient once they graduate and become independent clinicians. This level of preparedness may be evaluated by measuring clinical judgment (CJ) with the Lasater Clinical Judgment Rubric (LCJR). The LCJR contains 11 indicators that represent the actions and behaviors necessary for demonstrating CJ. Two methods of simulation, high fidelity patient simulation (HFPS) and objective structured clinical examination (OSCE), replicate the healthcare environment so students may safely demonstrate clinical skills without harming an actual patient. The purposes of this study were to 1) explore the use of the LCJR in the OSCE setting, and 2) elicit and compare the number of LCJR indicators that occur in the HFPS and OSCE settings for senior baccalaureate nursing students. Two research questions were explored: 1) comparing the representation of indicators between the OSCE and a single HFPS and question 2) comparing the representation of indicators between the OSCE and two HFPSs. Methods: This study used a two group, randomized crossover design with 23 senior nursing students in their last semester of a Bachelor of Science in Nursing program (n = 11; n = 12). Each participant performed patient care during two HFPS scenarios and 12 OSCE stations, followed by a written debriefing. Clinical performances were video recorded for each participant. CJ was evaluated by the reviewing the video recordings and counting the number of times an LCJR indicator occurred during the HFPS and OSCE settings. Counts for each indicator in each setting were established for the OSCE by adding indicator counts for each and for the HFPS by adding each indicator for the two scenarios. Comparisons of the OSCE to individual HFPSs as well as the combined HFPS means were performed using paired t-tests with an alpha value of 0.05. Results: The mean number of times that the LCJR indicators occurred in the OSCE setting was significantly higher (p < 0.05) than in either individual HFPS setting, indicating that the OSCE setting provided more opportunities for measuring CJ than a single HFPS setting. When comparing the OSCE to the combined HFPSs setting the mean counts of LCJR Indicators 3, 4, 5, 7, and 9 were higher in the OSCE, while counts for LCJR Indicators 2, 6, and 8 were higher in the combined HFPS settings. Indicators 3, 5, and 7 count means were more than five counts higher, indicating a likely impact on the accuracy of CJ scores regarding those indicators and a more favorable environment to measure those indicators within the OSCE setting. Participants reflected on their simulation experiences by answering written questions during the debriefing sessions to measure Indicators 10 and 11. Opportunities to measure Indicator 10 were similar between the two settings, while Indicator 11 occurred more in the students’ written OSCE debriefing than in HFPS debriefing. No variability existed with Indicators 10 and 11, thus statistical significance could not be determined. Conclusions: The overall higher mean count of LCJR opportunities in the OSCE setting suggests that OSCE provides a comparable number opportunities to measure CJ of senior nursing students. While previous research has validated the use of the LCJR tool in the HFPS setting, the results of this study suggest that the LCJR may be used in the OSCE setting and be similarly suitable. The OSCE uses less faculty resources than HFPS and thus may be a more cost-effective mode for evaluating CJ. However, additional research is needed to establish the validity and feasibility of using the LCJR tool in the OSCE setting to measure CJ in senior nursing students prior to graduation.
    • Effect of mentoring relationships on professional socialzation of the pre-licensure clinical nurse leader graduate

      Gazaway, Shena Borders; Department of Physiological and Technological Nursing (5/8/2017)
      The professional socialization of a nurse begins during their education experience and continues throughout their career as they acquire new roles and responsibilities. For pre-licensure clinical nurse leader graduates (PLCNLGs), the challenge is to meld the ideals learned during their education experience with the protocols and regulations necessary to practice successfully in their first professional nursing position. While all novice nurses experience difficulty with professional socialization, PLCNLGs have an additional stressor due to the prevailing belief that a Master’s-prepared nurse should be an expert nurse clinician before assuming the title of Clinical Nurse Leader. No matter their educational program, early professional socialization helps all newly licensed nurses, identify with the profession and provide a philosophical foundation with which to build a dynamic career. Mentoring is a low-cost strategy that may help achieve early professional socialization. Mentors provide the necessary support, career lifeline, and professional guidance during the PLCNLG’s transition from student to independent clinician. A positive mentoring relationship creates a trusted partner and confidant who eases the negative feelings associated with this transition process. Nursing research is needed to establish the best mentoring strategy to support the PLCNLG’s professionalism and career trajectory since differences exist in the foundation underlying each mentoring relationship. This study used a mixed methods longitudinal design with two instruments, the Nurses Professional Values Scale-Revised (NPVS-R) and the Nurses Role Conceptions Instrument (NRCI), plus focus groups to examine the impact formal and informal mentoring relationships had on the professional socialization of PLCNLGs. Participants were recruited from the pre-licensure Clinical Nurse Leader program nursing program of a large university located in the southeastern portion of the United States. Phase I data collection took place on campus just before graduation (n=69), nine months later the participants were approached to participate in the Phase II portion of data collection. A final sample of 22 participants completed Phase II with six of them participating in the focus groups. Using a one-way ANOVA, statistically significant differences were not found between the types of mentoring (formal, informal, both, none) and NPVS-R or NRCI bureaucratic and professional role orientation. However, a significant difference was seen with the service role discrepancy and mentoring relationship. Focus group results led to the development of a conceptual model which supports the manner in which mentoring impacted the professional socialization process of PLCNLGs. The integrated quantitative and qualitative results provided evidence that participants were greatly impacted by mentoring relationships. These relationships were established on trust and with people who were willing to help them grow in their nursing role. Participants reported increased confidence, comfort, and competence in their nursing role due to the actions of their mentors. The results of this study added critical knowledge regarding the professional socialization process from the perspective of the PLCNLG. The mixed method integrated approach highlighted how mentoring impacted this socialization process when quantitative analysis did not produce statistically significant results. Nurse executives and leaders should use this research to establish goals for employing mentors and successfully cultivating best practice for pairing mentors and mentees to decrease PLCNLG employment dissatisfaction and turnover.
    • A New Method For Analyzing 1:N Matched Case Control Studies With Incomplete Data

      Jin, Chan; Department of Biostatisctics and Epidemiology (5/8/2017)
      1:n matched case-control studies are commonly used to evaluate the association between the exposure to a risk factor and a disease, where one case is matched to up till n controls. The odds ratio is typically used to quantify such association. Difficulties in estimating the true odds ratio arise, when the exposure status is unknown for at least one individual in a group. In the case where the exposure status is known for all individuals in a group, the true odds ratio is estimated as the ratio of the counts in the discordant cells of the observed two-by-two table. In the case where all data are independent, the odds ratio is estimated using the cross-product ratio from the observed table. Conditional logistic regression estimates are used for incomplete matching data. In this dissertation we suggest a simple method for estimating the odds ratio when the sample consists of a combination of paired and unpaired observations, with 1:n matching. This method uses a weighted average of the odds ratio calculations described above. This dissertation compares the new method to existing methods via simulation.
    • Diabetic Membrane Repair Deficiency and Repair Promotion By Vitamin E

      Howard, Amber Cyran; Department of Cellular Biology and Anatomy (5/30/2014)
      Myopathy, characterized by muscle necrosis and atrophy, is a diabetic complication. The myopathy of at least one muscular dystrophy is linked to defective membrane repair. We hypothesized that defective membrane repair is also associated with diabetic myopathy. To test this hypothesis, we monitored repair in intact muscle from diabetic type 1 (INS2Akita+/-) and type 2 (db/db) mouse models. Myocytes were laser injured in the presence of a membrane impermeant dye, and cellular dye uptake through the disruption site was monitored. Dye influx of diabetic myocytes was significantly increased, compared to controls, indicating repair deficiency. This defect was mimicked in cultured cell models by high (30 mM) glucose exposure. Inhibiting the high glucose formation of advanced glycation endproducts (AGE) prevented this repair defect, but was induced in the absence of high glucose exposure by enhanced AGE receptor (RAGE) binding. We conclude that high glucose exposure leads to defective membrane repair in skeletal muscle, and that AGE/RAGE interactions underlie this defect. AGE/RAGE binding also induces generation of reactive oxygen species (ROS), which is increased in diabetes. ROS are also produced in skeletal muscle during eccentric contracts, an act that creates muscle membrane disruptions. Using a potent antioxidant, vitamin E (α-tocopherol), we were able to reverse the high glucose exposure repair defect. Interestingly, diets deficient in vitamin E results in a lethal muscular dystrophy. α-Tocopherol partitions into membrane bilayers where it is thought to act as a membrane stabilizer and/or as an antioxidant. We hypothesize that one important biological role of vitamin E is to promote muscle membrane repair. To test this hypothesis, cultured muscle cells were loaded with α-tocopherol and repair assessed with the laser assay. α-Tocopherol loading significantly decreased cellular dye influx, indicating that repair had been promoted. Strikingly, the HeLa cell, a non-muscle cell that normally displays unrestricted dye influx after laser disruption, e.g. not capable of repair via this form of injury, became repair competent after loading with α-tocopherol. Vitamin C, another antioxidant that can be loaded into cells, also significantly decreased dye influx after laser injury. However, horseradish peroxidase, an antioxidant that lacks transport across the plasma membrane was found to be ineffective in promoting repair. Cells injured in the presence of H2O2, displayed significantly more dye influx than controls injured in physiological saline lacking this oxidant. If however cells were loaded with vitamin E the H2O2 did not affect repair. We further tested H2O2 exposure in intact mouse skeletal muscle, and found repair to be significantly impaired. However, comparable to vitamin E loading in the cell model, Trolox (a water soluble analog of vitamin E) pretreatment prevented the H2O2 muscle membrane repair defect. We conclude that vitamin E promotes plasma membrane repair, and that its capacity as an anti-oxidant is crucial in this role.
    • Investigating Student and Faculty Perspectives Related to Predictors of Success: BSN Curriculum and NCLEX-RN Outcomes

      Callan, Richard S.; Department of Advanced Studies and Innovation (Augusta University, 5/22/2018)
      The literature reports higher patient satisfaction when care is delivered from baccalaureate-prepared nurses (BSN); however, there is a significant shortage of BSN prepared nurses in the country (Schmidt & MacWilliams, 2015; Roa, Shipman, Hooten, & Carter, 2011). For institutions across the nation, there is a lack of understanding as to why certain students struggle academically throughout the program and on the board certification exam. In order to facilitate training, graduation, and success with NCLEX-RN outcomes for these critical healthcare providers, consideration for why students struggle with curriculum and passing the board certification examination is needed. This study utilized a concurrent embedded mixed methods design to gain a greater understanding as to what factors may be contributing to student difficulty. Participants included graduates (n = 75) and faculty (n = 25) within the College of Nursing in a university located in the southeast region of the United States. Data were collected through review of student records, survey responses, focus group participation, and use of the EQ-i 2.0 for descriptive purposes. Results indicate that the BSN GPA, HESI examination scores, and Adult Health II course grades were found to predict performance on the NCLEX-RN. The qualitative findings illuminate categories of external and interpersonal factors contributing to students’ success and first time pass rates on the NCLEX-RN. The themes of Curriculum, Test Methodologies and Preparation, Teaching and Instruction, Balance, Drive, Compassion and Respect, and Critical Thinking were all relevant for consideration to help nursing programs improve the first time pass rates of their graduates on the NCLEX-RN. Further research utilizing methods to understand emotional intelligence and implications for admission as well as successful outcomes on the NCLEX-RN are indicated based on the qualitative findings of this investigation.
    • MECHANISM OF 12/15 LIPOXYGENASE-INDUCED RETINAL MICROVASCULAR DYSFUNCTION IN DIABETIC RETINOPATHY

      Elmasry, Khaled; Department of Biochemistry and Molecular Biology / Cancer Center (5/22/2018)
      Our earlier studies have established the role of 12/15-lipoxygenase (LO) in mediating the inflammatory reaction in diabetic retinopathy. However, the exact mechanism is still unclear. The goal of the current study was to identify the potential role of endoplasmic reticulum (ER) stress as a major cellular stress response in the 12/15-LO-induced retinal changes in diabetic retinopathy. We used in vivo and in vitro approaches. For in vivo studies, experimental diabetes was induced in wild-type (WT) mice and 12/15-Lo (also known as Alox15) knockout mice (12/15-Lo−/−); ER stress was then evaluated after 12-14 weeks of diabetes. We also tested the effect of intravitreal injection of 12-hydroxyeicosatetraenoic acid (HETE) on retinal ER stress in WT mice and in mice lacking the catalytic subunit of NADPH oxidase, encoded by Nox2 (also known as Cybb) (Nox2−/− mice). In vitro studies were performed using human retinal endothelial cells (HRECs) treated with 15-HETE (0.1 µmol/l) or vehicle, with or without ER stress or NADPH oxidase inhibitors. This was followed by evaluation of ER stress response, NADPH oxidase expression/activity and the levels of phosphorylated vascular endothelial growth factor receptor-2 (p-VEGFR2) by western blotting and immunoprecipitation assays. Moreover, real-time imaging of intracellular calcium (Ca2+) release in HRECs treated with or without 15-HETE was performed using confocal microscopy. Deletion of 12/15-Lo significantly attenuated diabetes-induced ER stress in mouse retina. In vitro, 15-HETE upregulated ER stress markers such as phosphorylated RNA-dependent protein kinase-like ER-regulated kinase (p-PERK), activating transcription factor 6 (ATF6) and protein disulfide isomerase (PDI) in HRECs. Inhibition of ER stress reduced 15-HETE-induced-leukocyte adhesion, VEGFR2 phosphorylation and NADPH oxidase expression/activity. However, inhibition of NADPH oxidase or deletion of Nox2 had no effect on ER stress induced by the 12/15-LO-derived metabolites both in vitro and in vivo. We also found that 15-HETE increases the intracellular calcium in HRECs. ER stress contributes to 12/15-LO-induced retinal inflammation in diabetic retinopathy via activation of NADPH oxidase and VEGFR2. Perturbation of calcium homeostasis in the retina might also play a role in linking 12/15-LO to retinal ER stress and subsequent microvascular dysfunction in diabetic retinopathy.
    • Female Teens Step It Up with the Fitbit Zip: A Randomized Controlled Pilot Study

      Linck, Donna Teresa; Department of Physiological & Technological Nursing (5/22/2018)
      Physical inactivity is a global pandemic. Six percent of all deaths globally (approximately 3.2 million people) are the result of insufficient physical activity, and 80% of adolescents worldwide do not get the recommended levels of daily physical activity. Depression is a major cause of disability worldwide and is a significant disease of burden for most age groups. Female adolescents are more than twice as likely to experience depressive symptoms as their male counterparts. The primary purpose of this randomized controlled pilot study was to determine if the use of electronic activity monitors, specifically Fitbit Zips, and daily step goals would increase physical activity participation in female adolescents. The secondary purpose was to determine if participation in a 12-week intervention using Fitbit Zips together with step goals would reduce depressive symptoms in female adolescents. The tertiary purpose was to determine the feasibility of recruiting and retaining female adolescents (80% or more) in the study and having them adhere to the research protocol. There were no available research studies examining physical activity and depressive symptoms in female adolescents using Fitbit Zips as an intervention to increase physical activity and decrease depressive symptoms. A convenience sample of 44 female adolescents from two church youth groups in the southeastern United States participated in the study. The mean age of the participants was 16.6 years. Psychosocial variables such as self-efficacy, social support, and commitment to a plan of action were assessed. Using mixed model analysis, no significant differences (p = .678) were found between the experimental (Fitbit-E) and control groups (Fitbit-C) on average median steps per day. The Fitbit-C group had 6,088.3 (SE = 668.6) average median steps per day at baseline, but only had 2,783.7 (SE = 698) average median steps per day at posttest. The Fitbit-E group had a lesser decline with 6,279.1 (SE = 661) average median steps per day at baseline and 4,339.4 (SE = 728) average median steps per day at posttest. Both groups’ depression scores, as measured by the CES-D, decreased from pretest to posttest, indicating an improvement in depressive symptoms. However, the difference between the two groups on depression scores was not statistically significant (p = .425). Post hoc pairwise comparisons yielded statistically significant decreases in depression scores for the Fitbit-C group (p = .002) and for the Fitbit-E group (p < .001) from pretest to posttest. Additionally, 42 out of 44 participants (95%) completed final CES-D surveys, and 35 out of 44 (79.5%) had some final step count data at post-test. Therefore, it was feasible to recruit and retain 80% of the participants in this RCT pilot study, and they did adhere to the protocol. This study helps bring to light the importance of promoting physical activity and assessing for depressive symptoms in the female adolescent population. Although there were no significant differences between the experimental and control groups on depressive symptoms for the 12-week intervention period, within each group there were significant decreases in depressive symptoms. The results from this study provide the groundwork to further investigate the impact of EAMs on physical activity and depressive symptoms in female adolescents.
    • Role of NADPH Oxidase following Traumatic Brain Injury

      Ma, Merry Wenlan; Department of Neuroscience and Regenerative Medicine (5/22/2018)
      Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Despite intense investigation, no neuroprotective agents for TBI have yet translated to the clinic. Recent efforts have focused on identifying potential therapeutic targets that underlie the secondary TBI pathology that evolves minutes to years following the initial injury. Oxidative stress is a key player in this complex cascade of secondary injury mechanisms and prominently contributes to neurodegeneration and neuroinflammation. In addition, the NLRP3 inflammasome, which produces pro-inflammatory signals, can become activated in response to oxidative stress and may exacerbate secondary pathology. NADPH oxidase (NOX) is a unique family of enzymes whose primary function is to produce reactive oxygen species (ROS). Human post-mortem and animal studies have identified elevated NOX2 and NOX4 levels in the injured brain, suggesting that NOX is involved in the pathogenesis of TBI. Our experiments demonstrate that targeting NOX, specifically NOX2 and NOX4, can reduce oxidative stress, attenuate neuroinflammation, reduce lesion size, and promote neuronal survival following TBI. In particular, deletion of NOX2 or inhibition of NOX can attenuate the increased expression and activation of the NLRP3 inflammasome via TXNIP- mediated pathway and decrease the production of pro-inflammatory factors, such as caspase-1 and IL-1β. We also demonstrate the novel findings that deletion of NOX4 can reduce neuronal oxidative damage evidenced by decreased DNA oxidation, lipid peroxidation, and protein nitration in the injured cerebral cortex. Mice lacking NOX4 also showed reduced cell death and neurodegeneration following TBI. Collectively, our results support the notion that targeting NOX enzymes can suppress neuroinflammatory secondary TBI pathology in addition to alleviating oxidative damage following injury. In addition, our inhibitor studies extend the critical window of efficacious TBI treatment, which further supports the pursuit of NOX as therapeutic targets.
    • Early Life Environmental Exposure and Hormonal Exposure and Race-Related Influence on the Human Stem Cell Populations in Fibroid and Myometrial Tissues Lead to Compromised Genomic Integrity and Increased Tumorigenesis

      Prusinski Fernung, Lauren; Department of Neuroscience and Regenerative Medicine (5/22/2018)
      Though benign, uterine fibroids (UF) are the most significant benign neoplastic threat to women’s health and most common indication for hysterectomy. The elusive etiology of UF inhibits significant improvement in quality of care for affected women. Somatic mutations in the MED12 gene are currently thought to arise in myometrial stem cells (MSCs) converting them into UF tumor-initiating cells. Defective DNA repair increases the risk of tumorigenic somatic mutations, suggesting that additional mutations arising in fibroid stem cells (FSCs) ultimately contribute further to tumor growth and development. In addition, a significant ethnic disparity exists in UF prevalence, occurring in African American (AA) four times more as compared to Caucasian (CA) women, a phenomenon that has been observed for more than 120 years, but the molecular attributes behind UF’s ethnic disparity are still not fully realized. Our goal is to determine the mechanism by which the physiology of these human uterine MSCs is altered by changes in utero during early development of the epigenetic regulators of DNA-damage repair genes and how these stem cells lead to the origination of MED12 mutations and, ultimately, UF development later in adult life. Using a rat model of early-life environmental exposure, in which rats undergoing early uterine development were exposed to an endocrine disruptor, we compared the DNA repair capacity of exposed, "at-risk" myometrial stem cells to those from unexposed animals. In addition, we utilized human myometrial and fibroid tissue samples to characterize the myometrial stem cell populations from normal versus fibroid-containing uteri and compared the DNA repair capacity of human fibroid stem cells to the stem cells of adjacent myometrium. We determined that DNA repair in both exposed rat MSCs and human FSCs was decreased/altered compared to unexposed murine MSCs and human adjacent MSCs, respectively. In exposed rat MSCs, DNA double-strand break (DSB) repair was significantly impaired both in untreated cells and in cells in which DNA DSB damage was induced. Similar phenomena were observed in human FSCs as compared to adjacent MSCs. These data suggest impaired DNA repair in exposed MSCs and in human FSCs may contribute to initiation and perpetuation of UF tumorigenesis.
    • Relationships among Health Literacy, Self-Care, and Hospital Readmission Status in African American Adults with Heart Failure

      Sarfo, Robert; Department of Physiological and Technological Nursing (5/22/2018)
      Approximately six million adults are diagnosed with heart failure (HF) yearly in the U.S., with one million subsequent hospitalizations. Of these, 25%-30% are readmitted within 30 to 90 days of initial discharge. Little is known about relationships among health literacy (HL), self-care and 30-day hospital readmission status in adult African Americans (AAs) with HF. The primary purpose of this study was to explore relationships among HL, baseline self-care maintenance (BSCM), and 30-day hospital readmission status in adult AAs with HF. Two secondary purposes were to determine whether BSCM mediated the relationship between HL and readmission status and whether there was a moderating effect of age, gender, education, insurance status and perceived social support (PSS), on the relationships of HL with BSCM and readmission status. Using a one-month prospective cohort design, HL, BSCM, PSS, basic conditioning factors, and 30-day readmission status were measured in participants from two large hospitals in the Central Savannah River Area in Georgia. Statistical analyses included logistic regression, Pearson product-moment correlation, chi-square tests of independence, and mediation and moderation analyses. Eighty-nine participants were enrolled in this study. Most participants (71.9%) were male, and their mean age was 53.25 years (Standard Deviation, SD = 12.74; range 25-88 years). Of the 89 participants, 28.1% experienced at least one readmission within 30 days of discharge. The following findings have p values < .05. BSCM varied significantly with HL (X2 = 6.97 (degrees of freedom, df = 2, sample size (N) = 89)). Higher PSS was significantly associated with higher BSCM (r = .29). HL was significantly correlated with age (r = -.62). The influence of age on the relationship between HL and readmission status was significant (b = .005). Elderly patients (> 65 years) scoring high on HL had a higher probability of readmission, and younger patients (< 40 years) scoring low on HL had a higher probability of readmission. Post hoc analysis showed that lower ejection fraction predicted readmissions (odds ratio = 3.1, 95% confidence interval = 1.03 - 9.05) after controlling for the other predictors. The findings provide a basis for further research to better understand the impact of HL, self-care maintenance, and other patient characteristics on readmission of AAs with HF.
    • NLRP3 Inflammasome-Mediated Uncoupling of Hippocampal Vasoneuronal Communications in Diabetes: Relevance to Cognitive Impairment and Stroke

      Ward, Rebecca; Department of Neuroscience and Regenerative Medicine (5/22/2018)
      Diabetes is a prevalent chronic disease that affects over 29 million individuals in the United States and 422 million people worldwide as of 2017. Given the high mortality and morbidity associated with diabetes due to its complications including retinopathy, chronic kidney disease, peripheral neuropathy, heart disease and stroke, this increase in incidence of diabetes creates many clinical, social and economic problems. A silent, but unrecognized complication of diabetes is cognitive impairment, which ranges from mild cognitive impairment to dementia. The increased risk and incidence of stroke amplifies these cognitive deficits. The objectives of this dissertation were to 1) determine the role and mechanism(s) by which diabetes worsens cognitive decline and 2) determine the extent and mechanism by which NLRP3 activation contributes to poor cognitive function after stroke in diabetes. To investigate these objectives, feeding rats a high fat diet and administering a low dose of streptozotocin was used as a clinically relevant diet-enhanced model of diabetes. Stroke was induced through either transient MCAO (60 or 90 min) or embolic MCAO. Embolic stroke caused more severe hippocampal neurovascular injury, microglial activation and cognitive decline in diabetes as compared to stroke induced by a shorter 60 min suture occlusion of the MCA. Diabetic females were more sensitive to ischemic injury than males. Furthermore, hippocampal vascularization patterns at baseline and after ischemic injury differed in males and females and despite these sex differences in the extent and patterns of hippocampal neurovascular injury, diabetes worsened cognitive outcomes in both sexes. Collectively, these first studies provide a preclinical foundation for future studies addressing cognitive impairment in diabetes in both sexes. NLRP3 inflammasome, which cleaves IL-1β and IL-18 into their active forms, was upregulated in diabetes and amplified following ischemia. Inhibition of the NLRP3 inflammasome with MCC950, a specific small molecule inhibitor of NLRP3 activation, improved post-stroke cognition, reduced hippocampal cell death, was associated with less leaky vasculature, and blunted chronic inflammation in the hippocampus after 90-min MCAO. MCC950 did not seem to provide neuroprotection to the neuron through the mBDNF, but did reduce cell death after hypoxia/reoxygenation in vitro. These results are the first to provide essential data showing that MCC950 has the potential to become a therapeutic agent to prevent neurovascular remodeling and worsened cognitive decline in diabetic patients following stroke. Collectively, this work may provide a piece of the puzzle explaining how diabetes leads to cognitive impairment and worsens outcome following acute ischemic injury, and it provides a potential therapeutic target to treat cognitive impairment after stroke, especially in diabetic patients.
    • IN VITRO AND IN VIVO STUDIES DEMONSTRATE A ROLE FOR SH3PX1 IN LAMELLIPODIA FORMATION.

      Hicks, Lawrence Joseph; Department of Cellular Biology and Anatomy (5/22/2018)
      Actin remodeling and endocytosis are essential functions for most cells. Defects in these processes present in a variety of diseases. Sorting nexins are known to contribute to endocytic uptake, cytokinesis, the retromer complex, and autophagy. Sorting nexin 9 (Snx9) interacts with major endocytic factors and proteins involved in regulation of actin cytoskeleton dynamics. Nonetheless, Snx9’s exact in vivo roles in these basic cellular processes and disease mechanisms are not known. By examining the roles of Sh3px1, we can better understand the mechanism by which this protein contributes to endocytosis and actin remodeling in vivo. Two additional paralogs, Snx18 and Snx33, complicate studies in mammalian models due to potential redundant mechanisms. Utilizing the single ortholog in Drosophila, sh3px1, this report describes the function of Sh3px1 in membrane organization and actin dynamics. Drosophila S2 cells that are depleted of Sh3px1 fail to form lamellipodia, a process that is also dependent on the actin nucleation factor, Scar. In addition, over-expression of Sh3px1 in S2 cells results in the formation of tubules and also long membrane protrusions, atypical of a classical BAR domain protein. An intact PX-BAR domain is required for these overexpression phenotypes. sh3px1 null flies are viable; however, mutant females have significantly compromised fertility. Female sh3px1 null egg chambers show many morphological defects. The age-dependent degeneration of the null egg chamber is not likely due to compromised endocytosis. Additionally, collective border cell migration is attenuated in the absence of Sh3px1. These cells are known for their reliance on endocytosis and modulation of actin dynamics for migration. We have found that Sh3px1 is essential in efficient lamellipodia production at the start of border cell migration. Our findings also suggest that Scar directly interacts with Sh3px1 and is upregulated in sh3px1 nulls. Mutation of Scar enhances many reproductive defects in sh3px1 nulls. Thus, our work reveals a main in vivo function of Sh3px1 in actin regulation for the production of structures such as lamellipodia.
    • Investigating Student and Faculty Perspectives Related to Predictors of Success: BSN Curriculum and NCLEX-RN Outcomes

      Cosper, Sharon M; Department of Advanced Studies and Innovation (Augusta University, 5/22/2018)
      The literature reports higher patient satisfaction when care is delivered from baccalaureate-prepared nurses (BSN); however, there is a significant shortage of BSN prepared nurses in the country (Schmidt & MacWilliams, 2015; Roa, Shipman, Hooten, & Carter, 2011). For institutions across the nation, there is a lack of understanding as to why certain students struggle academically throughout the program and on the board certification exam. In order to facilitate training, graduation, and success with NCLEX-RN outcomes for these critical healthcare providers, consideration for why students struggle with curriculum and passing the board certification examination is needed. This study utilized a concurrent embedded mixed methods design to gain a greater understanding as to what factors may be contributing to student difficulty. Participants included graduates (n = 75) and faculty (n = 25) within the College of Nursing in a university located in the southeast region of the United States. Data were collected through review of student records, survey responses, focus group participation, and use of the EQ-i 2.0 for descriptive purposes. Results indicate that the BSN GPA, HESI examination scores, and Adult Health II course grades were found to predict performance on the NCLEX-RN. The qualitative findings illuminate categories of external and interpersonal factors contributing to students’ success and first time pass rates on the NCLEX-RN. The themes of Curriculum, Test Methodologies and Preparation, Teaching and Instruction, Balance, Drive, Compassion and Respect, and Critical Thinking were all relevant for consideration to help nursing programs improve the first time pass rates of their graduates on the NCLEX-RN. Further research utilizing methods to understand emotional intelligence and implications for admission as well as successful outcomes on the NCLEX-RN are indicated based on the qualitative findings of this investigation.
    • Examining and Fostering Effective Reading Comprehension Instructional Practices in Smalltowne

      Zills, Jennifer Amy; Department of Advanced Studies and Innovation (Augusta University, 5/22/2018)
      Abstract This mixed-methods study examined reading instructional practices at Smalltowne Elementary, as almost 30% of their third grade students were not scoring proficient in the area of English Language Arts (ELA) on the state assessment. Smalltowne is a rural elementary school located in a southeast Georgia town with a population of just under 10,000. A total of 18 female participants included both second grade (n = 9) and third grade (n = 9) teachers. Participants completed an online survey of the Literacy Orientation Survey (LOS) containing 30 Likert type items to determine their teaching orientations as either traditional, constructivist, or eclectic. Researchers interviewed 14 participants and spent a total of 50.25 hours observing instructional practices in the areas of reading comprehension, vocabulary instruction, phonics, fluency, and literacy through technology. The teachers’ survey results were compared to the observed practice to determine alignment. Nine teachers identified as eclectic, eight identified as traditional and only one teacher identified as constructivist. Observed literacy practices matched self-selected LOS scores for 11 out of the 14 teachers. Observations were conducted to determine if research-based instructional strategies were being used in the classroom, including comprehension strategies, vocabulary strategies, fluency practices, and literacy through technology. Instructional concerns were noted with higher usage of teacher-directed practice and lack of authentic use of technology for literacy to incorporate more student-centered practice. After the analysis of data, a responsive product in the form of professional development was created by researchers with input from district school leaders to expand teachers’ use of higher level questioning and technology within the classroom. Keywords: teacher orientations, reading comprehension, instructional practices