• Factors associated with turnover among nurses in Taiwan

      Yang, Ke-Ping Agnes; School of Nursing (1987-12)
      The purpose of this study wasta examine the factors r~lated to nurses' turnover in Taiwan, the Republiq, of Ghina. Abelson~s (1986) lntegrCllted Turnover a I I ' Process Model, which ass~mes a causal relationship between an-employee's perceptions of indi~idual, organizational, atld environmental factors and that individual's decision to leave thei·r job, provided the theoretical basis for this - r . . study. A retrospective, descriptive correlational study design was-employed. Two h~ndred ar:1d thirty-$eve~ n~wly hi..red registered nurses who nad vo'lu~tarily le~ ~heir last position within the lasj twelve months were chos~n from eight large teac~ing hospitals loqated in the f110St populated areas o.f Taiwan .. A two-part \ questionnaire, an adaptation of--McCios-key's 1974 toolJor studying nursing turnover in the U.~. was used to collect.the da~a. ,A paQel of ~ive experts judged ~ - \, -- ' ' ,.. _.... . tbe final questio,nnaire-to have .conter:1t and translation validity. The Cronbach's alpha reliability score for Part ll_~f the que$tionn~ire us~d in, thi~ st~,Jdy w~s 0.98. Organizational ·level factors considered' most impo~ant when seeking a job were cited by 84.4 percent of t~e respondents. All 45 reward or incentive items in Part II of the questionnaire would have influenced some of the respondents to remain in their last position. Correlation statistics, Pearson r, t-Test, and ·one-way AN OVA were employed to test the relationships between ten selected fndividual, organizational, o~ environmental level variables and . nurses' length of service. Finding$ indicate that there was a significant relationship between length of service and age, marital status, relationship behavior, salary, hospital bed size, and type of hospital (private or public). , - The desire for better financial compensation for their work, opportunities for career advancement through continuing and formal education, more professional recognition from their supervisors, pe·ers, and physicians for their contribution to patient care, and more autonomy in their clinical practice appear to be shared by nurses in the Republic of China and the United States. Recommended approaches based on these findings which will assist administrators in retention as well as recruitment of nurses are presented.
    • Factors in student attrition

      Laird, Lee; Nauright, Lynda; School of Nursing (1973-12)
    • False coverage rate - adjusted smoothed bootstrap simultaneous confidence intervals for selected parameters

      Sun, Jing; Department of Biostatistics and Epidemiology (Augusta University, 2020-05)
      Many modern applications refer to a large number of populations with high dimensional parameters. Since there are so many parameters, researchers often draw inferences regarding the most significant parameters, which are called selected parameters. Benjamini and Yekutieli (2005) proposed the false coverage-statement rate (FCR) method for multiplicity correction when constructing confidence intervals for only selected parameters. FCR for the confidence interval method is parallel to the concept of the false discovery rate for multiple hypothesis testing. In practice, we typically construct FCR-adjusted approximate confidence intervals for selected parameters either using the bootstrap method or the normal approximation method. However, these approximated confidence intervals show higher FCR for small and moderate sample sizes. Therefore, we suggest a novel procedure to construct simultaneous confidence intervals for the selected parameters by using a smoothed bootstrap procedure. We consider a smoothed bootstrap procedure using a kernel density estimator. A pertinent problem associated with the smoothed bootstrap approach is how to choose the unknown bandwidth in some optimal sense. We derive an optimal choice for the bandwidth and the resulting smoothed bootstrap confidence intervals asymptotically to give better control of the FCR than its competitors. We further show that the suggested smoothed bootstrap simultaneous confidence intervals are FCR-consistent if the dimension of data grows no faster than N^3/2. Finite sample performances of our method are illustrated based on empirical studies. Through these empirical studies, it is shown that the proposed method can be successfully applied in practice.
    • Feasibility of immunogold visualization of nuclear antigens by scanning electron microscopy

      Smith, Mary Leverett; Department of Cell and Molecular Biology (1987-09)
    • Fecal Streptococci Determinations In Water From a Small Urban Lake and Tributary

      Bruker, Eugene; Department of Cell and Molecular Biology (1962-06)
    • 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.
    • The fenestrations of serious membranes in relation to lymphatic absorption

      Williams, William B.; Department of Anatomy (1971-06)
    • FLAGELLAR CHAPERONES AND CONTROL OF CAMPYLOBACTER JEJUNI MOTILITY

      Fiedler, Jarred; Department of Biochemistry and Molecular Biology (2018-11)
      Campylobacter jejuni is a leading cause of bacterial gastroenteritis, with an annual incidence of 140 million cases globally and 1.3 million cases in the United States. Approximately 1/1000 of C. jejuni infections lead to the onset of Guillain-Barré Syndrome, the world’s leading cause of acute paralysis. While the pathogenic mechanisms of C. jejuni are incompletely understood, it is known that flagellar motility is a primary virulence factor. Flagella are involved in host cell adherence and invasion, biofilm formation, and chick colonization. Flagellar assembly is dependent on the coordinated regulation of flagellar subunit synthesis via transcriptional and post-transcriptional regulators, as well as flagellar chaperones which maintain flagellar subunits in an unfolded state. In C. jejuni, the post-transcriptional regulator CsrA regulates flagellar biogenesis in C. jejuni by binding to the mRNA for flaA, repressing FlaA synthesis. CsrA regulatory activity on flagellar and non-flagellar targets is predicted to be modulated by protein-protein interactions with the flagellar chaperone FliW. Both FliW and a second flagellar chaperone FliS are predicted to participate in flagellar assembly by binding to FlaA. Therefore, we investigated the roles of FliW and FliS in CsrA regulation and flagellar biogenesis by constructing and characterizing a fliS mutant of C. jejuni strain 81-176, and by testing for the presence of protein-protein interaction(s) among CsrA, flagellin, and flagellar chaperones. We created an in-frame deletion mutant of fliS, and determined that the deletion of fliS resulted in a loss of motility and reduced the capacity of C. jejuni to autoagglutinate and form biofilm. We also used a bacterial two-hybrid system to study possible binding among the flagellarrelated proteins FlaA, FliS, FliW, and CsrA. Additionally, we performed deletion analysis of fliW in pT25, with the goal of identifying the region of FliW that mediates binding to CsrA. CsrA bound to full-length FliW, but no other protein-protein interactions were evident using the two-hybrid system. Surprisingly, CsrA did not interact with fragments of FliW, suggesting that the CsrA-binding site of FliW may be complex. These results show that flagellar biogenesis is accomplished by interactions of flagellar chaperones that link motility with the regulation of Campylobacter pathogenesis-related properties.
    • Fluoride metabolism : effect of caffeinated beverages / by Xiaoyan Chen.

      Chen, Xiaoyan; Department of Oral Biology (1992-05)
    • From Adipokines to Atherosclerosis: The Role of Adipose Tissue in Inflammation and Etiology of Vascular Disease

      Bundy, Vanessa; Vascular Biology Center (2007-04)
      The prevalence of overweight and obese has steadily increased over the years among males and females of all ages, all racial and ethnic groups, and all educational levels. Recent studies have established adipose tissue as a dynamic, endocrine organ with the capacity to secrete a number of adipokines which may act directly upon the vasculature to stimulate adhesion molecule expression and exacerbate vascular disease. Our aim was to elucidate the associations of vasoactive pro- and anti- inflammatory factors, including adhesion molecules, with adiposity, blood pressure and endothelial function, and to distinguish race and sex variations in these relationships. To accomplish this, we expanded upon existing measurements within a Georgia Prevention Institute cross-sectional study entitled Lifestyle, Adiposity & Cardiovascular Health in Youths (LACHY) by adding two cardiovascular disease risk factor domains: inflammation and vascular adhesion. Our model included measurements of adiposity, adiponectin, C-reactive protein, leptin, insulin, resistin, tumor necrosis factor-a, interleukin-6, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, blood pressure and endothelial-dependent arterial dilation. Our findings include numerous race and sex differences in the concentration of circulating risk factors along with significant interactions between them and measurements of adiposity. However, we did not find circulating cardiovascular disease risk factors or their concentration differences to be significantly associated with blood pressure or endothelial function. We believe this to be largely due to the fact that our subjects were young and apparently healthy at time of measurement. Overall, our findings provide insight into the relationships between adiposity, inflammation and cardiovascular outcomes in black and white, male and female adolescents. Future studies are needed to further elucidate these relationships and how they may change over time.
    • The Function of NELF and ESR1 in Puberty Development and Fertility

      Quaynor, Samuel Nii Djangmah; Department of Obstetrics and Gynecology (2013-07)
      Reproductive disorders affect 10-15% of the population in the United States and result in debilitating social and economic issues. Reproductive dysfunction may be displayed as delayed puberty or infertility due to defects in the hypothalamic-pituitary gonadal (HPG) axis. This axis is controlled by gonadotropin releasing hormone (GnRH) through the release of GnRH peptide. An important critical barrier to understanding normal puberty is the lack of known specific genes that regulate the development, migration and function of hypothalamic GnRH neurons, which synthesize and secrete GnRH neuropeptide in a pulsatile pattern into the portal blood. Several human diseases occur as the result of impaired GnRH function. Idiopathic hypogonadotropic hypogonadism (IHH) patients present with decreased gonadotropins and sex steroids leading to permanent delayed of puberty and infertility. Kallmann syndrome (KS) combines IHH phenotypes in addition to anosmia/hyposmia as there is impairment in migration o f GnRH neurons and olfactory neurons/axons. To date, the molecular basis has only been identified for approximately 40% o f all IHH/KS patients. The purpose of this study was to understand the role and function o f genes, such as NELF (nasal embryonic LHRH factor), in pubertal development and fertility. NELF, a nuclear protein isolated from migratory GnRH neurons, has been shown to be involved in the pathogenesis of IHH/KS, and knockdown impairs GnRH neuron migration in vitro. The mechanism o f NELF’s role relevant to GnRH migration/signaling and its effects on pubertal development and fertility are unclear. NELF function has been studied in GnRH cell lines, but not in the whole organism. The overall goals of this study are to characterize the phenotypic features of /Ve/^knockout (KO) mice, classify the prevalence of the different variants of NELF reported, and the inheritance patterns of IHH/KS genes including NELF, and finally examine the phenotype and hormonal profile o f an estrogen receptor-a (ESR1) mutation in a woman. Methods: Following breeding of heterozygous mice to generate homozygous N elf knockout mice, pubertal onset was assessed by daily monitoring of weight, vaginal opening (females), and anogenital distance (males). In addition we determined fertility of the mice by doing a continuous 90 day breeding study. Immunocytochemical labeling o f GnRH neurons was performed and analyzed for migration and count; hematoxylin and eosin stains were performed to visualize gonadal morphology. Three additional studies were also performed: 1) NELF splice variants were studied in immortalized human and mouse GnRH neurons; 2) the prevalence of digenic disease in IHH/KS was determined when the 13 most common genes were sequenced in 48 patients; and 3) the first woman with an estrogen receptor-a (ESR1) mutation was characterized clinically and by in vitro analysis. Results: Female NelfK O mice had delayed puberty, small uteri, and a decrease in GnRH neuron distribution distance, but male KO mice had normal puberty and GnRH neuron distribution distance. Both male and female KO mice had decreased litter size. Furthermore, NELF variant 2 was the dominant variant in both mouse and human GnRH neurons. Both nuclear and non-nuclear splice variants were expressed at the RNA and protein levels. DNA sequencing of 13 genes in 48 IHH/KS patients demonstrated that -90% of the cases are monogenic. Finally, the ESR1 mutation in the female patient led to absent pubertal development as ESR1 signaling is profoundly defective.
    • Function of TNF Death Receptors in Apoptosis and Cancer Immune Surveillance

      Hu, Xiaolin; Department of Biochemistry and Molecular Biology (2012)
      Tumor necrosis factor receptor (TNFR) is a group of death receptors that can mediate extrinsic apoptosis in target cells upon specific ligand engagement. Members of the TNFR super family play a pivotal role in cytotoxic T cell-mediated immune surveillance and immune regulation. However, cancer cells can acquire apoptosis resistance through down-regulating surface TNFR level or alteration of key mediators in the TNFR signaling pathway so that cancer cells can evade TNFR-mediated and immune cell-based cytotoxicity. Therefore, understanding the underlying mechanism of cancer resistance to TNFR-mediated apoptosis will provide the basis for identifying specific molecular targets and effecient cancer therapy. In this study, we discovered that chronic myelogeneous leukemia (CML) cells use DNA methylation to down-regulate IRF8, a tumor suppressor gene, to acquire apoptosis resistance to Fas-mediated apoptosis. More importantly, we showed that acid ceramidase is a transcription target of IRF8. Restoration of IRF8 or inhibition of acid ceramidase can re-sensitize CML cells to FasL-induced apoptosis in vitro. Furthermore, such manipulation can prolong mouse survival in vivo. While targeting Fas-mediated apoptosis is one strategy to restore immune cell-mediated surveillance, targeting other TNFR members sheds light on monoclonal antibody (mAb) based therapy. We demonstrated that LTβR, as a member of the death receptor super family, could function in cancer immune surveillance through mediating tumor cell apoptosis in sarcoma, colon and mammary carcinoma in a caspase dependent way. Because LTR is selectively up-regulated on cancer cells, it could potentially be a good target for cancer-selective killing. Targeting the TNFR pathway might not only eliminate tumors, but it may also emerge as a promising target to eliminate myeloid derived suppressor cells that accumulate in the peripheral blood under neoplastic conditions. We demonstrated that tumor induced myeloid derived suppressor cells (MDSC) were more resistant to apoptosis than the cells with the same phenotype in tumor free mice. We also identified that up-regulation of Bcl-xL is one of the mechanisms responsible for apoptosis resistance in tumor induced MDSC and that inhibiting Bcl-xL by BH3 mimetics could greately sensitize MDSC to FasL induced apoptosis.
    • Functional analysis of a hematopoietic-specific gene identified using high-throughput tissue-specific cDNA screening in zebrafish

      Marty, Scott D.; School of Graduate Studies (2001-06)
      Zebrafish hematopoiesis begins in an intra-embryonic tissue called the intermediate cell mass (ICM), which specifically expresses the erythroid-specific transcription factor GATA-1. Using a cDNA library constructed from embryonic zebrafish GATA-1- positive cells, we identified a prothymosin alpha-like gene, ProTaL-1. RNA whole mount in situ hybridization showed that ProT~-1 was specifically expressed in the ICM. Microinjection of a construct encoding ProTa.L-1 fused to the green fluorescent protein revealed nuclear localization of ProTa.L-1. Oye~-expression of ProTaL-1 mRNA increased gata-1 expression, whereas knockdown ofProTaL-1 using an antisense, morpholino oligonucleotide resulted in a specific decrease of gata-1 expression in whole embryos. Fluorescence activated cell sorting analy~is of green fluorescent proteinlabeled GATA-I-positive cells from transgenic zebrafish indicated that ProTa.L-1 acted primarily to increase the total number· of ~mbryonic hematopoietic cells. s·ince prothymosin alpha is conserved among species, ProTa.L-1 may play a role in promoting , ' proliferation ofhematopoietic-ptogenitor cells in,higher vertebrates.
    • Functional Characterization of the P53 Family Protein P63 and the EPHA2 Receptor Tyrosine Kinase, a Novel P53 Family Target Gene

      Dohn, Michael Robert; Department of Biochemistry and Molecular Biology (2001-10)
      A cell’s ability to survive as part of a multicellular organism often depends on how well it communicates with other cells in its surrounding environment. The need for coordinated and complementary cellular activities requires a means o f sending and receiving signals to and from neighboring cells. This is achieved by the presence of an assortment of proteins both linked to and within the plasma membrane. The plasma membrane acts as a barrier between the intracellular and extracellular milieu, and plasma membrane proteins allow for much o f the communication between these two environments. An important class o f proteins found on the plasma membrane is the superfamily of receptor protein tyrosine kinases (RPTKs). RPTKs are membrane-spanning proteins, that contain domains on both sides of the plasma membrane, joined by a single transmembrane domain (1). Binding of a growth factor or cytokine to the extracellular domain of an RPTK results in receptor dimerization and autophosphorylation o f specific tyrosine residues on the cytosolic domains (1). These phosphotyrosine residues then act as docking sites for cytosolic proteins containing modular structures such as Srchomology- 2 (SH2) and phosphotyrosine binding (PTB) domains (2). Binding of SH2- and PTB-containing proteins initiates an intracellular signaling cascade that often results in the regulation of transcription factors in the nucleus (3-5). It is through these RPTKmediated cascades that many extracellular signals are received by a cell.