• Tissue culture study of clinical specimens from an outbreak of rubella-like illness

      Reddick, Rhoda Anne; Department of Cell and Molecular Biology (1965-06)
    • Tissue metabolism of thyroid hormones in hypothyroid and growth hormone treated hypothyroid mothers, their fetuses and their progenies

      Berdecia-Rodriguez, Joseph; Department of Physiology and Endocrinology (1990-05)
      Studies of Man et al. have shown that the children of hypothyroxinemic women have an .increased rate of mental and .motor retardation. A rat model which presents the ~etabolic and motor defects of these children developed by Hendrich et al. was used for these studies. The metabolism of T4 was studied i~ the progenies of Tx-only and GH-treated Tx dams utilizing a radioimmunoassay for T4 detection and equations based on those of Inglebleek .~d Malvaux. In the above mentioned study, the hypothyroid dams showed an impaired reproductive performance that included lower body weight gain, smaller liter size and greater mortality for their pups. Furthermore, maternal hypothyroidism had a detrimental effect on their offsprings body and tissue weights. The parameters of metabolism for T4 showed that the offsprings of hypothyroid mothers have a clear derangement in the utilization of this hormone at the ages studied (i.e., 5, 30, 60 days of age). The next step in our investigation wa~ to measure the iodothyronine concentrations intracellularly to determine how these J molecules were utilized. We developed a new technique for the extraction of iodothyronines based on HPLC fluorescence. The extracted iodothyronines were derivatized with dansyl chloride and then rap in our chromatographic system. The iodothyronine concentrations ·in the tissues {i.e., brain and liver) and plasma for the progenies of hypothyroid mothers at all ages {i.e,. 22 day, 10, 30, 60 day-olds} were consistently abnormal confirming what we saw with the metabolic studies of T4 done initially. The hypothyroid mothers had iodothyronine concentrations consistently abnormal in all tissues studies. The progenies of hypothyroid mothers appear to suffer an insult that causes a severe impairment in the metabolism of T4. This insult not only affects the metabolism of T4 but also affects the concentrations' of other iodothyronines in liver, brain and plasma
    • Toll-like receptor 2 contributes to cerebrovascular dysfunction and cognitive impairment in diabetes

      Hardigan, Trevor; Department of Physiology (2016-03)
      The risk of cognitive decline in diabetes (Type 1 and Type 2) is significantly greater compared to normoglycemic patients, and the risk of developing dementia in diabetic patients is doubled. The etiology for this is likely multifactorial, but one mechanism that has gained increasing attention is decreased cerebral blood flow (CBF) as a result of cerebrovascular dysfunction. The innate immune system has been shown to play a role in diabetic vascular complications, notably through Toll-like receptor (TLR) stimulated release of proinflammatory cytokines and chemokines that leads to vascular damage. TLR2 has been implicated in the development of diabetic microvascular complications such as nephropathy, and thus we hypothesized that TLR2-mediated cerebrovascular dysfunction leads to decreased CBF and cognitive impairment in diabetes. Vascular TLR2 expression was increased and local TLR2 antagonism improved cerebrovascular function in diabetes. While the anti-hyperglycemic dipeptidylpeptidase-IV (DPP-IV) inhibitor linagliptin prevented TLR2 expression in brain microvascular endothelial cells (BMVEC) when applied locally, chronic in vivo treatment did not decrease vascular smooth muscle TLR2 expression. Treatment with linagliptin restored CBF in diabetes independent of effects on blood glucose levels, and this increase in CBF was correlated with decreased endothelin-1 (ET-1)-mediated vasoconstriction, decreased pathological remodeling, and increased endothelium-dependent relaxation. Knockout of TLR2 conferred protection from impaired CBF in early-stage diabetes and from hyperperfusion in long-term diabetes, prevented the development of endothelium dependent vascular dysfunction in diabetes, created a hyperactive and anxiolytic phenotype, and protected against diabetes induced impairment of long term hippocampal- and prefrontal cortex- mediated fear learning. In conclusion, these findings support the involvement of TLR2 in the pathogenesis of diabetic vascular disease and cognitive impairment.
    • Toll-like receptor 9 contributes to vascular dysfunction in hypertension

      McCarthy, Cameron; Department of Physiology (2016-03)
      Inappropriate immune system activation is common in hypertension; however, the exact mechanisms by which this occurs are not well understood. Innate immune system recognition and response to damage-associated molecular patterns (DAMPs) is becoming an increasingly accepted mechanism. Mitochondrial DNA (mtDNA) is a DAMP that is recognized by Toll-like receptor (TLR)9, and it is elevated in the circulation of spontaneously hypertensive rats (SHR). Therefore, we hypothesized that (1) inhibition of TLR9 in SHR with a TLR9 antagonist (ODN2088) or TLR9 inhibitor (chloroquine) would lower blood pressure and improve vascular function and that (2) treatment of normotensive rats with a TLR9 agonist (ODN2395) would cause vascular dysfunction and increase blood pressure. Both ODN2088 and chloroquine lowered high blood pressure in SHR and treatment with chloroquine also improved cyclooxygenase-dependent endothelial function and prevented the full recruitment of the adaptive immune system in SHR. On the other hand, treatment of normotensive rats with ODN2395 increased blood pressure and rendered their arteries less sensitive to acetylcholine-induced relaxation and more sensitive to norepinephrine-induced contraction. This dysfunctional vasoreactivity was due to cyclooxygenase activation, increased reactive oxygen species generation, and reduced nitric oxide bioavailability. In conclusion, these findings support the involvement of the innate immune system pattern recognition receptor TLR9 in the pathogenesis and maintenance of hypertension. Specifically, circulating mtDNA may activate TLR9 and contribute to high blood pressure and endothelial dysfunction in SHR.
    • Transcriptional Coactivator and Oncoprotein CoAA

      Brooks, Yang Sui; Department of Pathology (2008)
      CoAA contains two copies of RNA recognition motifs (RRM) and an intrinsic transactivation domain rich in repetitive tyrosines and glutamines (YxxQ domain). Previously, CoAA has been shown to be a transcriptional coactivator that stimulates transcriptional activation and regulates alternative splicing. A pattern and profile search revealed that the YxxQ domain in CoAA shared significant pattern homology with the oncogenic EWS activation domains (EAD) in TET family proteins, including, TLS/FUS, EWS and TAFII 68. It was further demonstrated that CoAA’s YxxQ domain and EWS’ EAD also shared functional similarities. Based on these findings, this work investigated the aberration of CoAA in cancers and its pathophysiological significance. The results showed that the CoAA gene was amplified in a high percentage of inflammation-related human cancers with recurrent loss of the 5’ regulatory element upstream of its promoter. This genomic aberration resulted in CoAA protein overexpression, which in turn, induced the transformation of NIH3T3 cells. Subsequently, it was shown that the lost 5’ regulatory element could modulate the alternative splicing of the CoAA gene during stem cell differentiation and that the unbalanced expression of CoAA and its splice variant, CoAM could potentially impact the cell differentiation process. To further characterize the regulation of CoAA alternative splicing, two conserved trans-splicing events between CoAA and its downstream RBM4 were identified. These events yield a novel zinc finger- containing coactivator, CoAZ, and a non-coding splice variant, ncCoAZ. Both variants regulated their parental genes’ mRNA expression as well as activities, suggesting a linked control between CoAA and RBM4. Moreover, the expression patterns of CoAA, RBM4 and their trans-splicing variants switched during neural stem cell differentiation, resulting in lineage-specific expression of each variant. Our phylogenetic analysis suggests that mammalian CoAA and RBM4 share a common ancestor with the Drosophila melanogaster gene, Lark. In this regard, the trans-splicing events between CoAA and RBM4 represent a functional regulation preserved during evolution. This study established the connection between CoAA and human cancer and provides evidence for CoAA’s involvement in the regulation of cell differentiation. Moreover, this study is the first to report a functional trans-splicing variant in mammalian cells.
    • Transcriptional Regulation by Tbx2

      Chen, Jung-Ren; Department of Pathology (2001-03)
      Tbx2 is a member of an evolutionarily conserved transcriptional regulatory gene family. Little is known about the molecular mechanisms underlying the function of Tbx2. Because connexin43 (Cx43) and Tbx2 are both expressed in neural crest derivatives in pharyngeal arches and because the promoter of Cx43 contains direct repeats of T (Brachyury) half sites, it is hypothesized that Tbx2 regulates Cx43 and other genes important for neural crest cell functions. TBX2 DNA binding affinity was analyzed by eletrophoretic mobility shift assays. Transcriptional regulation of the Cx43 promoter by Tbx2 was analyzed using reporter constructs. These results suggest that Cx43 is a bona fide target gene o(Tbx2 and that Tbx2 negatively regulates Cx43 gene expression by binding to TCACAC sites. Moreover, dye-coupling assays showed that Tbx2 upregulation led to decreased junctional coupling. To identify other genes that may be regulated by Tbx2, a differential gene expression profile was determined using GEM1 microarrays. CellSpace knowledgebase was used to perform functional assignments to 72>x2-regulated genes. This analysis indicated that Tbx2 might be involved in different fundamental cell functions. Tbx2 upregulates proliferation genes, downregulates tenascinC, and upregulates nidogen. In conclusion, together with Cx43 repression, Tbx2 may signal neural crest cells to stop migration and start proliferation. Gene cluster analysis also suggested a potential role for Tbx2 in osteogenesis. In accord, Tbx2 expression was detected in chondrocytes and osteocytes both in long bone and membranous bones.
    • Transformation from Informal Community Group to Community-Based Health Care Organization: A Case Study of Change

      Hanson, Glenda F; Department of Physiological and Technological Nursing (1996-03)
      The purpose o f this study was to examine the transformations of the organization, AID Atlanta in it’s first ten years to determine how and why decisions were made which lead from an informal community group to the creation of the successful, viable, community-based health care organization. Case study methodology was used to conduct the investigation. Sources o f data included primary and secondary documents, direct observations, and systematic interviewing. The theoretical framework for this study was the theory of dissipative structures, as developed by Prigogine (1976) and others within the fields of biology and chemistry. A number o f social scientists have applied this theory to the study of organizational change and transformation. The theory conceptualizes organizations as open systems that exchange energy with the environment, are self determining, and self organizing. Change is conceived as a normal response to an uncertain and complex environment. The study found that AID Atlanta underwent a series o f changes and transformations which enabled it to grow, survive and remain viable. Forces influencing the organization came from both the internal and external environment, with the most powerful force being the AIDS epidemic. Decisions were made by numerous individuals which served to shape the success o f the organization. The clear and constant mission of the organization was a positive sustaining force, and the development of linkages to the community was a key factor in securing necessary resources. Implications o f the study are that decision makers in community-based health care organizations must expect and prepare for change. Knowledge of the experiences of similar successful organizations may lead the administrator to develop strategies which may serve to promote their own success. Strategies shown to promote viability in this study included an open exchange with the internal and external environments, a willingness to change, the use of resources from external connections, articulation o f a vision based on the mission, knowledgeable and experienced leaders, and a strong foundation and heritage.
    • Transformation of neisseria gonorrhoeae with gonococcal and meningo- coccal DNA

      Wood, David Oliver; Department of Cell and Molecular Biology (1975-06)
    • A Transforming Growth Factor From MCG-T14 Mouse Mammary Carcinoma Cells

      Cheng, Charles; Department of Cell and Molecular Biology (1983-04)
      Mitogenic activity was assayed in the harvest fluid concentrates (HFC) from. human· mammary cell.lines ·(T47P, HSO 578T, MDA-157, HBL-100 and BT-20) and a mouse mamamry carcinOinii (MCG-T14) cell line. Data showed that the HFC from four of the human cell lines (T47D,.HSO 578T, MDA-157, and HBL-fOO) and the mouse cell line (MCG-Tl4) were sour.ces of mitogenic activity. The mitogenic activity from the HFC was not due to the action of the serine protease, plasminogen activator. The mitogenic substance was also not a cell degradation product. The HFC from the human mammary carcinoma line BT-20 contained a non-dialyzable inhibitory activity which su~pressed the activities of the mitogerts in fetal bovine serum. Attempts to isolated the mitogenic activity from HFCs proved impractical due to proteolytic breakdown. However, a transforming growth factor (TGF) from acid-ethanol extracts of MCG-T14'mouse mammary carcinoma ' ' cells was isolate~ and·partially characterized. This factor stimulated thymidine uptake in BALB/c 3T3 cells and promoted anchorage-independent growth of NRK-49F cells in soft agar. The mitogenic activity, designated T14-TGF, stimulted thymidine uptake in conflue.nt-quiescent BALB/c 3T3 cells to the same extent as tha,t exhibited by 5% calf serum. T14-TGF was potentiated by EGF in its ability to promote colonial growth of NRK-49F cells. In competition binding assays, T14-TGF and EGF competed for binding to BALB/c 3T3 and A431 cells. However, EGF was a more efficien~ competitor than T14-TGF in all experiments and T14-TGF exhibited only partial inhibition of EGF-binding to A431 cells. This suggests that T14-TGF may have contained subfractions which did not compete for EGF binding sites. Nerve growth factor, fibroblast growth factor, and multiplication stimulating activity did not compete with T14-TGF for binding .. 1 sites .on BALB/c 3T3 cells. In addition, iodinated T14-TGF did not bind to NR6/6 3T3 cells which lack EGF receptors. It was concluded that Tl4-TGF must interact with EGF receptors specifically~ 2 T14-TGF was purified to apparent electrophoretic homogeneity by electroelution from 15% SDS-urea polyacrylamide gelso The factor was basic (pi 8.3), had anapparent moleculaJ; weight of 14,000 and was selectively inactivated by trypsin. In addition, T14-TGF exhibited no proteolytic activity and contained no carbohydrate residues. The biological activity of T14-TGF was resistant to inactivation by acid or heat and· denaturation by guanidine HCl. T14-TGF was completely inactivated by treatment with dithiothreitol which indicated that it required one or more intact disulfide .bridges for activ~ty. A unique characteristic of T14 ... TGF was that this factor bound very strongly to. both DEAE or carboxymethyl f:on excha'Iigers. T14-TGF contained high proportions of basic amino acid residues lys~ne and arginine.
    • Transient Self-Association of Beta2-Adrenergic Receptors

      Lan, Tien-Hung; Department of Pharmacology and Toxicology (2014-03)
      G-protein coupled receptors (GPCRs) constitute the largest family of cell surface receptors. Through binding to ligands such as hormones, peptides, neurotransmitters, or photons, GPCRs are activated and regulate a variety of physiological responses. It has been widely accepted that GPCRs can self-associate as dimers or higher-order oligomers even though protomeric GPCR is capable of activating heterotrimeric G proteins and recruiting arrestins. Although GPCR complexes have been suggested to possess distinct functional properties such as receptor trafficking, receptor phosphorylation, biased downstream signaling, and allosteric communication, the stability and the structural mechanisms for the dimerization of class A GPCRs have not been extensively studied. The β2 adrenergic receptor (β2AR) is a prototype of class A GPCRs and is probably the most extensively studied among the currently available high resolution crystal structures of GPCRs. However, lack of clear dimer interface and the controversy of the stability of β2AR dimeric complexes brings to the question that whether β2AR self-associate as a stable dimer.
    • THE TUMOR SECRETORY FACTOR ZAG PROMOTES WHITE ADIPOSE TISSUE BROWNING AND ENERGY WASTING IN CACHEXIA

      Elattar, Sawsan; Department of Biochemistry and Molecular Biology / Cancer Center (8/7/2018)
      SAWSAN ELATTAR The Tumor Secretory Factor ZAG Promotes White Adipose Tissue Browning and Energy Wasting in Cachexia (Under the direction of SATYANARAYANA ANDE) Cachexia is a complex tissue-wasting syndrome characterized by inflammation, hyper-metabolism, increased energy expenditure and anorexia. Browning of white adipose tissue (WAT) is one of the significant factors that contribute to energy wasting in cachexia. Tumors secrete an array of secretory factors, such as tumor necrosis factor α (TNFα), interleukin-1 (IL-1), interleukin-6 (IL-6), interferon γ (IFNγ) and zinc-α2-glycoprotein (ZAG), that have been implicated in altering metabolism and promoting cachexia. Previous studies have demonstrated that ZAG can induce lipolysis; however, whether ZAG plays a role beyond lipolysis remains unclear. Here, by utilizing a cell implantation model, we demonstrate that the lipid-mobilizing factor, ZAG, induces WAT browning in mice. Increased circulating levels of ZAG not only induced lipolysis in the adipose tissues, but also caused robust browning in the WAT. Stimulating white adipose progenitors with ZAG recombinant protein or expression of ZAG in mouse embryonic fibroblasts (MEFs) strongly enhanced brown-like differentiation. At the molecular level, ZAG stimulated peroxisome proliferator-activated receptor gamma (PPARƔ) and early B cell factor 2 (Ebf2) expression and promoted their recruitment to the PR/SET domain 16 (Prdm16) promoter, leading to enhanced expression of Prdm16, which determines brown cell fate. In the brown adipose tissue (BAT), ZAG stimulated the expression of PPARƔand peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) and promoted recruitment of PPARƔ to the uncoupling protein 1 (UCP1) promoter, leading to increased expression of UCP1. Collectively, by promoting WAT browning and by activating thermogenesis in the BAT, ZAG increased body energy expenditure. Overall, our results revealed a novel function of ZAG in WAT browning and highlight that targeting ZAG may have therapeutic applications in humans with cachexia. KEYWORDS: (Cachexia, beige adipocyte, brown fat, adipose atrophy, Zinc-α2-glycoprotein, Ebf2, Prdm16, PPARƔ, UCP1)
    • TWO-SAMPLE TESTS FOR HIGH DIMEMSIONAL MEANS WITH PREPIVOTING and DATA TRANSFORMATION

      Hellebuyck, Rafael Adriel; Department of Biostatistics and Epidemiology (2019-01-08)
      Within the medical field, the demand to store and analyze small sample, large variable data has become ever-abundant. Several two-sample tests for equality of means, including the revered Hotelling’s T2 test, have already been established when the combined sample size of both populations exceeds the dimension of the variables. However, tests such as Hotelling’s T2 become either unusable or output small power when the number of variables is greater than the combined sample size. We propose a test using both prepivoting and Edgeworth expansion that maintains high power in this higher dimensional scenario, known as the “large p small n ” problem. Our test’s finite sample performance is compared with other recently proposed tests designed to also handle the “large p small n ” situation. We apply our test to a microarray gene expression data set and report competitive rates for both power and Type-I error.
    • Ultrastructural and functional effects of dimethylsulfoxide (DMSO) in the isolated kidney

      Jeske, Arthur Herbert; Department of Pharmacology and Toxicology (1975-06)
    • Ultrastructure of the crown cells of stingrays (Genus Dasyatis)

      Crandall, Wilson T; Department of Anatomy (1970-05)
    • Understanding African American women church members' health decision-making and described behavior: a qualitative inqui

      McCall, Amber Brown; Department of Biobehavioral Nursing (2011-12)
      This dissertation described the processes that African-American women church members used to make health decisions and investigated the experiences and perceptions that faith had on this cohort‘s health beliefs. African-American women historically have suffered disproportionately from health disparities, and African-American women church members have played a central role as their families‘ primary caregiver. It is perceived that faith-based interventions can be effective at reducing health disparities. However, there is little understanding of the impact on the health decision-making process. By undertaking an investigation into this process in a cohort of African-American women church members, this study incorporated and advanced nursing theories used to guide the development of risk-reduction interventions through describing and delineating the role of faith-based health decision-making. A purposive, intensity sample of eleven African-American women church members were recruited to participate. Naturalistic inquiry methodology was used to analyze the interview data, answering the following questions: 1) What process(es) do African-American women church members use to make health decisions, and what health behaviors do these women describe? 2) What is the role of faith (if any) in the health beliefs of African-American women church members? The results indicated religious faith was integrated throughout the health decision-making process; additionally, three overarching processes were used by the study subjects, which are described herein as: 1) Believing in God, 2) Empowering Self, and 3) Using Resources. This demonstrated that their faith was a major influence in the lives participants and that faith impacted their competence and ability to be empowered and resourceful—as well as influenced health decision-making. Due to the targeted, purposive sampling methods along with the qualitative nature of the data obtained from study participant interviews, these research results cannot be generalized to the general population of African-American women. Nevertheless, understanding the process of health decision-making in this sample may be important to enabling researchers, clinicians and clergy to promote further research regarding the interplay of faith in health decision-making, risk reduction activities, and quality of life. The implications for nursing theory, practice and research, and empowering the community are included, and provide the essential foundation for this study.
    • Understanding african american women church members' health decision-making and described behavior: a qualitative inquiry

      McCall, Amber Brown; College of Graduate Studies (2011-12)
      This' dissertation described the processes that African-American women church members used to make health decisions and investigated the experiences and perceptions that faith had on this cohort's health beliefs. African-American women historically have suffered disproportionately from health disparities, and African-American women church members have played a central role as their families' primary caregiver. It is perceived that faith-based interventions can be effective at reducing health disparities. However, there is little understanding of the impact on the health decision-making process. By . undertaking an investigation into this process in a cohort of African-American women church members, this study incorporated and advanced nursing theories used to guide the development of risk-reduction interventions through describing and delineating the role of faith-based health decision-making. A purposive, intensity sample of eleven African-American women church members were recruited to participate. . Naturalistic inquiry methodology was used to analyze the interview data, answering the following questions: 1) What process(es) do African-American women church members use to make health decisions, and what health behaviors do these women describe? 2) What is the role of faith (if any) in the health beliefs of African-American . women church members? VI The results indicated religious faith was integrated throughout the health decisionmaking process; additionally, three overarching processes were used by the study subjects, which are described herein as: 1) Believing in God, 2) Empowering Self, and . 3) Using Resources. This demonstrated that their faith was a major influence in the lives participants and that faith impacted their competence and ability to be empowered and resourceful-as well as influenced health decision-making. Due to the targeted, purposive sampling methods along with.the qualitative nature of the data obtained from study participant interviews, these research results cannot be generalized to the genera~ population of African-American women. Nevertheless, understanding the process of health decision~making in this sample may be important to enabling researchers, clinicians and clergy to promote further research regarding the interplay of faith in health decision-making, risk reduction activities, and quality of life. The implications for nursing theory, practice and research, and empowering the community are included, and provide the essential foundation for this study.