Neurons are able to maintain membrane potential and synaptic integrity by an intricate equilibrium of membrane transporter proteins and ion channels. Two membrane proteins of particular importance in the vertebrate retina are the excitatory amino acid transporters (EAATs) which are responsible for the reuptake of glutamate into both glial and neuronal cells and the sodium potassium chloride cotransporters (NKCCs) that are responsible for the uptake of chloride ions into the cell. NKCCs are electro-neutral with the uptake of 2 Cl- coupled to an exchange of a potassium and Na+ ion into the cells. Therefore, there is little change of cell membrane potential in the action of NKCCs. In this study the localization and function of EAATs in the distal retina is investigated. Whole cell patch clamp recordings in lower vertebrate retina have demonstrated that EAAT2 is the main synaptic EAATs in rod photoreceptors and it is localized to the axon terminals. Furthermore, the action of the transporter seems to be modified by intracellular calcium concentration. There is also evidence that EAAT2 might be regulated by feedback from the neuron network by glycinergic and GABAergic mechanisms. The second half of this study investigates expression of NKCCs in the retina by western blot analysis and quantitative polymerase chain reaction. There are two forms of NKCCs, NKCC1 and NKCC2. NKCC1 is mostly expressed in the central nervous system and NKCC2 was thought to only be expressed in the kidneys. NKCC1 is responsible for the majority of chloride uptake into neuronal and epithelial cells and NKCC1 is expressed in the distal retina where photoreceptors synapse on second order horizontal and bipolar cells. This study found the expression of NKCC1 in the distal retina to be regulated by temporal light and dark adaptation. Light adaptation increased phosphorylated NKCC1 expression (the active form of the cotransporter). The increase in NKCC1 expression during light adaptation was modulated by dopamine. Specifically, a D1 receptor agonist increased phosphorylated NKCC1 expression. Dopamine is an essential chemical and receptor known for initiating light adaptation in retina. Finally, an NKCC1 knockout mouse model was examined and it revealed that both forms of NKCC are expressed in the vertebrate retina. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Small conductance Ca2+-activated K+ (SK) channels have been shown to alter the encoding of spatial and non-spatial memory in the hippocampus by shaping glutamatergic postsynaptic potentials and modulating NMDA receptor-dependent synaptic plasticity. When activated, dendritic SK channels reduce hippocampal neuronal excitability and LTP. Similar SK channel properties have been demonstrated in lateral amygdala (LA) pyramidal neurons. Additionally, induction of synaptic plasticity and beta-adrenoreceptor activation in LA pyramidal neurons causes PKA-mediated internalization of SK channels from the postsynaptic density. Chronic activation of the amygdala through repetitive stressful stimuli can lead to excitatory synaptic strengthening that may create permanent hyper-excitability in its circuitry. This mechanism may contribute to a number of mood and anxiety disorders. The selective influence of SK channels in the LA on anxiety and fear conditioning are not known. The thesis project outlined herein examined whether SK channel blockade by bee venom peptide, apamin, during a repetitive acute fear conditioning paradigm was sufficient to alter fear memory encoding and the resulting behavioral outcome. Following the final fear memory test session, mice were tested in the open field immediately after the second fear conditioning test session. The findings indicate that intracranial LA microinfusions of apamin did not affect memory encoding or subsequent anxiety. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

The purpose of this study was to examine the acute and temporal response of CK- MM and FGF-21 to 3-day/wk. different repetition-range, volume-equated resistance training programs over 8-weeks in previously trained males. Sixteen trained, college- aged males were counterbalanced into high (DUP-HR) or low (DUP-LR) repetition groups. Subjects performed the squat and bench press 3x/wk. for 8 weeks. Blood samples were collected at various intervals throughout the study. Trained individuals did not elicit significant acute or chronic changes in CK-MM or FGF-21 following training and the lack of change was present in both groups. Additionally, neither biomarker correlated with changes in 1RM strength. There was a very strong correlation between acute mean (r=0.95) and acute percentage change (r=0.97) increase from pre training to post training in week #1. Additionally, a moderate correlation in percentage change was observed (r=0.59) of both biomarkers from pre training to 48 hours post training in week #2. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection

by Chan Po-cheung. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 218-244). / Acknowledgement --- p.i / Abbreviations --- p.ii / Abstract --- p.iv / Table of content --- p.ix / Chapter Chapter 1. --- Biochemistry of Tumor Necrosis Factor --- p.1 / Chapter I. --- Introduction --- p.1 / Chapter 1.1 --- The discovery of tumor necrosis factor (TNF) --- p.1 / Chapter 1.2 --- TNF as an antitumor agent --- p.3 / Chapter 1.3 --- Production of TNF --- p.4 / Chapter 1.4 --- Structure of TNF --- p.5 / Chapter 1.5 --- TNF receptor --- p.6 / Chapter 1.6 --- Biological activities of TNF --- p.10 / Chapter 1.7 --- Anti-tumor activity of TNF --- p.14 / Chapter 1.7.1 --- In vitro studies --- p.14 / Chapter 1.7.1.1 --- Synergistic effect of other cytokines --- p.14 / Chapter 1.7.1.2 --- DNA damages --- p.15 / Chapter 1.7.1.3 --- Free radical generation --- p.15 / Chapter 1.7.1.4 --- Utilization of ATP --- p.16 / Chapter 1.7.1.5 --- Phospholipase A2 activation --- p.17 / Chapter 1.7.2 --- In vivo studies --- p.17 / Chapter 1.8 --- Clinical trials --- p.18 / Chapter Chapter 2. --- Materials and Methods --- p.20 / Chapter 2.1 --- Materials --- p.20 / Chapter 2.2 --- Solutions commonly used --- p.21 / Chapter 2.3 --- Methods and procedure --- p.23 / Chapter 2.3.1 --- Culture of L-929 cells --- p.23 / Chapter 2.3.2 --- Trypan Blue exclusion test --- p.23 / Chapter 2.3.3 --- Determination of viability of L-929 cells upon rhTNF treatment --- p.24 / Chapter 2.3.4 --- Determination of cellular cAMP level --- p.25 / Chapter 2.3.5 --- Determination of inositol phosphate turnover --- p.26 / Chapter 2.3.6 --- Use of fluorescence probe in the study of rhTNF mediated killing --- p.28 / Chapter 2.3.6.1 --- Determination of changes in internal pH of L-929 cells --- p.29 / Chapter 2.3.6.2 --- Determination of intracellular calcium level in L-929 cells --- p.30 / Chapter 2.3.6.3 --- Determination of membrane potential by fluorescence probes --- p.32 / Chapter 2.3.6.4 --- "Translocation of nucleolar protein, nucleophosmin (B23)in L-929 cells" --- p.32 / Chapter 2.3.6.5 --- Determination of calcium mobilization in L-929 cells by confocal microscopy --- p.34 / Chapter 2.3.6.6 --- Determination of protein kinase C and phospho-tyrosine kinase in L-929 cells --- p.34 / Chapter 2.3.7 --- Uptake of 45Ca2+ in L-929 cells --- p.35 / Chapter 2.3.8 --- Measurement of membrane potential by Patch-clamp assay --- p.36 / Chapter 2.3.9 --- Determination of tyrosine kinase activation by Western blotting --- p.36 / Chapter 2.3.10 --- Statistical analysis --- p.38 / Chapter Chanter 3. --- Effect of rhTNF treatment on nucleophosmin in L-929 cells --- p.39 / Chapter 3.1 --- Introduction --- p.39 / Chapter 3.2 --- Results --- p.43 / Chapter 3.2.1 --- Effect of TNF (in the presence or absence of actinomycin D) on the nucleophosmin translocation in L-929 cells --- p.43 / Chapter 3.2.2 --- Effect of actinomycin D on the TNF-mediated cytotoxicity on L-929 cells --- p.51 / Chapter 3.3 --- Discussion --- p.57 / Chapter Chapter 4. --- Changes in membrane potential and intracellular pH in rhTNF-mediated cytotoxicity in L-929 cells --- p.59 / Chapter 4.1 --- Introduction --- p.59 / Chapter 4.2 --- Results --- p.61 / Chapter 4.2.1 --- Effect of rhTNF on the membrane potential of L-929 cells determined by fluorescence method --- p.61 / Chapter 4.2.2 --- Effect of rhTNF on the membrane potential of L-929 cells determined by patch clamp technique --- p.64 / Chapter 4.2.3 --- "Effect of K+, Na+ and pH on the rhTNF-mediated cytotoxicity on L-929 cells" --- p.67 / Chapter 4.3 --- Discussion --- p.90 / Chapter Chapter 5. --- Effect of intracellular cAMP and cAMP-dependent protein kinase (PKA) on the rhTNF-mediated cytotoxicity on L-929 cells --- p.92 / Chapter 5.1 --- Introduction --- p.92 / Chapter 5.1.1 --- "GTP-binding protein (G protein), cAMP and protein kinase A" --- p.92 / Chapter 2.1.2 --- Role of cAMP as second messenger --- p.96 / Chapter 5.1.3 --- Bacterial toxin used for study of G-protein --- p.98 / Chapter 5.1.4 --- Effect of cAMP on rhTNF cytotoxicity --- p.99 / Chapter 5.1.5 --- Effect of cAMP-dependent protein kinase (PICA) on rhTNF cytotoxicity --- p.101 / Chapter 5.2 --- Results --- p.102 / Chapter 5.2.1 --- Cyclic-AMP (cAMP) level in rhTNF-treated L-929 cells --- p.102 / Chapter 5.2.2 --- Effect of intracellular cAMP level on rhTNF-mediated cytotoxicity on L-929 cells --- p.104 / Chapter 5.2.3 --- Effect of agonist and inhibitor of cAMP dependent protein kinase (protein kinase A) on rhTNF-mediated cytotoxicity on L-929 cells --- p.107 / Chapter 5.2.4 --- Effect of protein kinase A inhibitors on rhTNF-mediated cytotoxicity on L-929 cells --- p.111 / Chapter 5.3 --- Discussion --- p.118 / Chapter Chapter 6. --- "Role of intracellular free calcium, ions and calcium dependent response in rhTNF-mediated cytotoxicity on L-929 cells" --- p.121 / Chapter 6.1 --- Introduction --- p.121 / Chapter 6.1.1 --- Inositol triphosphate and intracellular free calcium --- p.121 / Chapter 6.1.2 --- Diacylglycerol --- p.131 / Chapter 6.1.3 --- Protein kinase C (PKC) --- p.131 / Chapter 6.1.4 --- Intracellular free calcium ions and protein kinase C --- p.134 / Chapter 6.1.5 --- Effect of intracellular free calcium ions and protein kinase C on TNF-mediated cytotoxicity --- p.135 / Chapter 6.1.6 --- Tyrosine kinase induced release of IP3 --- p.136 / Chapter 6.1.7 --- Calcium channels --- p.136 / Chapter 6.2 --- Result --- p.139 / Chapter 6.2.1 --- Effect of rhTNF on intracellular free [Ca2+] of L-929 cells --- p.141 / Chapter 6.2.2 --- Effect of calcium ion channel blockers on rhTNF-mediated cytotoxicity on L-929 cells --- p.148 / Chapter 6.2.3 --- Effect of protein kinase C (PKC) on rhTNF-mediated cytotoxicity on L-929 cells --- p.158 / Chapter 6.2.4 --- Immunofluorescence staining of PKC in rhTNF-treated L-929 cells --- p.162 / Chapter 6.2.5 --- Effect of calmodulin and calmodulin sensitive calcium ATPase on rhTNF-mediated cytotoxicity on L-929 cells --- p.165 / Chapter 6.2.6 --- Role of inositol triphosphate in rhTNF-mediated cytotoxicity on L-929 cells --- p.167 / Chapter 6.2.7 --- Role of tyrosine kinase activity in the rhTNF-mediated cytotoxicity on L-929 cells --- p.185 / Chapter 6.3 --- Discussion --- p.191 / Chapter Chapter 7. --- Effect of antioxidants on rhTNF-mediated cytotoxicity on L-929 cells --- p.195 / Chapter 7.1 --- Introduction: Oxygen free radicals as mediators of rhTNF-induced tumor cell necrosis --- p.195 / Chapter 7.2 --- Results --- p.199 / Chapter 7.3 --- Discussion --- p.203 / Chapter Chapter 8. --- General Discussion --- p.205 / Bibliography --- p.217

by Chan Eliza. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 183-196). / ACKNOWLEDGEMENTS / ABSTRACT --- p.i / Chapter CHAPTER ONE: --- INTRODUCTION --- p.1 / Chapter CHAPTER TWO: --- LITERATURE REVIEW / Chapter Section 1: --- History of Merkel cells --- p.3 / Chapter Section 2: --- Morphology and characteristic response of Merkel cell receptors in the skin --- p.5 / Chapter Section 3: --- Merkel cells and other mechanoreceptors in the mammalian sinus hair --- p.16 / Chapter Section 4: --- Functions of Merkel cells --- p.29 / Chapter Section 5: --- Review of technical approaches in the study of Merkel cell physiology --- p.39 / Chapter Section 6: --- Monitoring intracellular Ca2+ with the microfluorimetric technique --- p.42 / Chapter Section 7: --- Properties of voltage-gated and ligand-operated Ca2+ channels --- p.52 / Chapter CHAPTER THREE: --- METHODS / Chapter Section 1: --- Isolation of the rat vibrissal follicles --- p.60 / Chapter Section 2: --- Procedures for fluorimetric studies --- p.63 / Chapter Section 3: --- Procedures for electrophysiological study --- p.72 / Chapter Section 4: --- Chemicals --- p.82 / Chapter CHAPTER FOUR: --- RESULTS / Chapter Section 1: --- Electrophysiological studies in an isolated sinus hair preparation --- p.89 / Chapter Section 2: --- Electrophysiological studies on slowly adapting type I (SA I) mechanoreceptors in an isolated skin-nervein vitro preparation --- p.109 / Chapter Section 3: --- Microfluorimetric studies of Merkel cells in the isolated sinus hair preparation --- p.117

Wong Hau Yan Connie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 86-95). / Abstracts in English and Chinese. / Abstract --- p.ii / Acknowledgements --- p.ix / Contents --- p.x / List of Figures --- p.xiii / List of Tables --- p.xv / Abbreviations --- p.xvi / Chapter Chapter 1: --- Introduction / Chapter 1.1 --- Role of extracellular nucleotides in equine sweat gland epithelial cells --- p.1 / Chapter 1.2 --- Subdivision of P1 and P2 purinoceptor --- p.4 / Chapter 1.3 --- General properties of P2 purinoceptor --- p.5 / Chapter 1.3.1 --- P2X purinoceptor family --- p.5 / Chapter 1.3.2 --- P2Y purinoceptor family --- p.8 / Chapter 1.4 --- The diversity of P2Y purinoceptor --- p.10 / Chapter 1.4.1 --- P2Y1 receptor --- p.10 / Chapter 1.4.2 --- P2Y2 receptor --- p.10 / Chapter 1.4.3 --- P2Y4 receptor --- p.10 / Chapter 1.4.4 --- P2Y6 receptor --- p.10 / Chapter 1.4.5 --- P2Y11 receptor --- p.11 / Chapter 1.5 --- The importance of calcium --- p.13 / Chapter 1.6 --- General aspects of calcium signaling --- p.14 / Chapter 1.7 --- Calcium release from the intracellular calcium stores --- p.15 / Chapter 1.7.1 --- Metabolism of inositol phosphates --- p.15 / Chapter 1.7.2 --- Ca2+ release from the internal calcium store --- p.15 / Chapter 1.8 --- Store-operated calcium channels (SOCC) or Capacitative calcium entry (CCE) --- p.18 / Chapter 1.8.1 --- The nature of the signal for CCE --- p.18 / Chapter 1.8.1.1 --- Conformational coupling --- p.18 / Chapter 1.8.1.2 --- Diffusible messenger --- p.21 / Chapter 1.9 --- Mechanism of intracellular calcium measurement --- p.25 / Chapter 1.10 --- Background of E92/3 cell line --- p.28 / Chapter Chapter 2: --- Materials and methods --- p.29 / Chapter 2.1 --- Cell culture --- p.29 / Chapter 2.2 --- Preparation of the simultaneous measurement --- p.31 / Chapter 2.2.1 --- Cell seeding --- p.31 / Chapter 2.2.2 --- Dye loading --- p.33 / Chapter 2.3 --- The setup of simultaneous measurement --- p.36 / Chapter 2.4 --- Statistical analysis --- p.40 / Chapter Chapter 3: --- Results --- p.41 / Chapter 3.1 --- Major domain of Ca2+ influx is from the basolateral side --- p.41 / Chapter 3.1.1 --- Effect of store depletion by apical ATP --- p.41 / Chapter 3.1.2 --- Effect of store depletion by basolateral ATP --- p.43 / Chapter 3.1.3 --- Effect of store depletion by thapsigargin --- p.47 / Chapter 3.2 --- Differential effect of apical and basolateral nucleotides on [Ca2+]i and Isc --- p.51 / Chapter 3.2.1 --- Basolateral ATP activates an increase in [Ca2+]i but not Isc --- p.51 / Chapter 3.2.2 --- Apical and basolateral ATP activated distinct but partially overlapped internal Ca2+ pool --- p.51 / Chapter 3.2.3 --- "Dose-dependent effect of apical or basolateral ATP, UDP and UTP on [Ca2+]i i and Isc" --- p.54 / Chapter 3.3 --- P2Y receptors subtypes on the basolateral membrane --- p.60 / Chapter 3.3.1 --- "Possible involvement of P2X, P2Y1 and P2Y11 purinoceptors on the basolateral membrane" --- p.60 / Chapter 3.3.2 --- "Cross-desensitization of experiments of UTP, ATP and UDP" --- p.60 / Chapter 3.4 --- The ATP-activated Ca2+ pool and thapsigargin-activated Ca2+ pool are partially overlapped --- p.68 / Chapter 3.5 --- Anion secretion activated by Ca2+ -independent pathway --- p.74 / Chapter Chapter 4: --- Discussion --- p.76 / Chapter 4.1 --- The major membrane for the CCE is from the basolateral side --- p.76 / Chapter 4.2 --- Basolateral P2Y receptors --- p.80 / Chapter 4.3 --- Differential effects of apical and basolateral ATP --- p.82 / Chapter 4.3.1 --- Apical and basolateral ATP release Ca2+ from different pools --- p.83 / Chapter 4.3.2 --- Ca2+ -independent mechanism --- p.83 / Chapter 4.3.3 --- Other potential signaling molecules --- p.84 / Chapter Chapter 5: --- Reference --- p.86

by Ho Wai Fong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 207-243). / Abstracts in English and Chinese. / Title --- p.i / Abstract --- p.ii / 摘要 --- p.v / Acknowledgements --- p.viii / Table of Contents --- p.x / List of Abbreviations --- p.xviii / List of Figures --- p.xxiv / List of Tables --- p.xxix / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Traumatic brain injury --- p.1 / Chapter 1.2 --- Ceils of the nervous system: glia --- p.1 / Chapter 1.2.1 --- Astroglia - / Chapter 1.2.1.1 --- Molecular markers of astroglia --- p.3 / Chapter 1.2.1.2 --- Functions of astroglia --- p.3 / Chapter 1.2.2 --- Oligodendrocyte --- p.5 / Chapter 1.2.2.1 --- Molecular markers of oligodendrocyte --- p.6 / Chapter 1.2.2.2 --- Functions of oligodendrocyte --- p.6 / Chapter 1.2.3 --- Microglia --- p.7 / Chapter 1.2.3.1 --- Molecular markers of microglia --- p.7 / Chapter 1.2.3.2 --- Functions of microglia --- p.8 / Chapter 1.3 --- Cytokine and brain injury --- p.8 / Chapter 1.4 --- Tumor necrosis factor alpha (TNF-α) --- p.9 / Chapter 1.5 --- TNF-α receptor --- p.10 / Chapter 1.6 --- Biological activities of TNF-α --- p.11 / Chapter 1.7 --- Signaling mechanism --- p.13 / Chapter 1.7.1 --- Protein kinase C --- p.13 / Chapter 1.7.2 --- Protein kinase A --- p.14 / Chapter 1.7.3 --- p38 mitogen-activated protein kinase (p38 MAPK) --- p.15 / Chapter 1.7.3.1 --- Biological activities of p38 MAPK --- p.18 / Chapter 1.7.4 --- Inducible nitric oxide synthase (iNOS) --- p.20 / Chapter 1.7.5 --- cAMP responsive element binding protein (CREB) --- p.21 / Chapter 1.7.6 --- Transcription factor c-fos --- p.23 / Chapter 1.7.7 --- Nuclear factor kappa-B (NF-kB) --- p.24 / Chapter 1.8 --- "Brain injury, astrogliosis and scar formation" --- p.26 / Chapter 1.9 --- β-adrenergic receptor (β-AR) --- p.28 / Chapter 1.9.1 --- Functions of β-AR in astrocytes --- p.29 / Chapter 1.10 --- Why do we use C6 glioma cell? --- p.31 / Chapter 1.11 --- Fluorescent differential display (FDD) --- p.34 / Chapter 1.12 --- Aims and Scopes of this project --- p.36 / Chapter Chapter 2 --- MATERIALS AND METHODS / Chapter 2.1 --- Material --- p.40 / Chapter 2.1.1 --- Cell line --- p.40 / Chapter 2.1.2 --- Cell culture reagents --- p.40 / Chapter 2.1.2.1 --- Complete Dulbecco's modified Eagle medium (CDMEM) --- p.40 / Chapter 2.1.2.2 --- Rosewell Park Memorial Institute (RPMI) medium --- p.41 / Chapter 2.1.2.3 --- Phosphate buffered saline (PBS) --- p.41 / Chapter 2.1.3 --- Recombinant cytokines --- p.41 / Chapter 2.1.4 --- Chemicals for signal transduction study --- p.42 / Chapter 2.1.4.1 --- Modulators of p38 mitogen-activated protein kinase (p38 MAPK) --- p.42 / Chapter 2.1.4.2 --- Modulators of protein kinase C (PKC) --- p.42 / Chapter 2.1.4.3 --- Modulators of protein kinase A (PKA) --- p.42 / Chapter 2.1.4.4 --- β-Adrenergic agonist and antagonist --- p.43 / Chapter 2.1.5 --- Antibodies --- p.44 / Chapter 2.1.5.1 --- Anti-p38 mitogen-activated protein kinase (p38 MAPK) antibody --- p.44 / Chapter 2.1.5.2 --- Anti-phosporylation p38 mitogen-activated protein kinase (p-p38 MAPK) antibody --- p.44 / Chapter 2.1.5.3 --- Antibody conjugates --- p.44 / Chapter 2.1.6 --- Reagents for RNA isolation --- p.45 / Chapter 2.1.7 --- Reagents for DNase I treatment --- p.45 / Chapter 2.1.8 --- Reagents for reverse transcription of mRNA and fluorescent PCR amplification --- p.45 / Chapter 2.1.9 --- Reagents for fluorescent differential display --- p.46 / Chapter 2.1.10 --- Materials for excision of differentially expressed cDNA fragments --- p.46 / Chapter 2.1.11 --- Reagents for reamplification of differentially expressed cDNA fragments --- p.46 / Chapter 2.1.12 --- Reagents for subcloning of reamplified cDNA fragments --- p.47 / Chapter 2.1.13 --- Reagents for purification of plasmid DNA from recombinant clones --- p.47 / Chapter 2.1.14 --- Reagents for DNA sequencing of differentially expressed cDNA fragments --- p.47 / Chapter 2.1.15 --- Reagents for reverse transcription-polymerase chain reaction (RT-PCR) --- p.48 / Chapter 2.1.16 --- Reagents for electrophoresis --- p.50 / Chapter 2.1.17 --- Reagents and buffers for Western blot --- p.50 / Chapter 2.1.18 --- Other chemicals and reagents --- p.50 / Chapter 2.2 --- Maintenance of rat C6 glioma cell line --- p.51 / Chapter 2.3 --- RNA isolation --- p.52 / Chapter 2.3.1 --- Measurement of RNA yield --- p.53 / Chapter 2.4 --- DNase I treatment --- p.53 / Chapter 2.5 --- Reverse transcription of mRNA and fluorescent PCR amplification --- p.54 / Chapter 2.6 --- Fluorescent differentia display --- p.55 / Chapter 2.7 --- Excision of differentially expressed cDNA fragments --- p.59 / Chapter 2.8 --- Reamplification of differentially expressed cDNA fragments --- p.59 / Chapter 2.9 --- Subcloning of reamplified cDNA fragments --- p.60 / Chapter 2.10 --- Purification of plasmid DNA from recombinant clones --- p.63 / Chapter 2.11 --- DNA sequencing of differentially expressed cDNA fragments --- p.64 / Chapter 2.12 --- Reverse transcription-polymerase chain reaction (RT-PCR) --- p.66 / Chapter 2.13 --- Western bolt analysis --- p.67 / Chapter Chapter 3 --- RESULTS / Chapter 3.1 --- DNase I treatment --- p.71 / Chapter 3.2 --- FDD RT-PCR and band excision --- p.71 / Chapter 3.3 --- Reamplification of excised cDNA fragments --- p.74 / Chapter 3.4 --- Subcloning of reamplified cDNA fragments --- p.77 / Chapter 3.5 --- DNA sequencing of subcloned cDNA fragments --- p.77 / Chapter 3.6 --- Confirmation of the differentially expressed cDNA fragments by RT-PCR and Western blotting --- p.84 / Chapter 3.6.1 --- Effects of TNF-α on p38a mitogen protein kinase (p38 α MAPK) --- p.84 / Chapter 3.6.2 --- Effects of TNF-α on p38 a MAPK and p-p38 α MAPK protein level --- p.86 / Chapter 3.7 --- Effects of TNF-α on p38 MAPK --- p.88 / Chapter 3.7.1 --- "Effects of TNF-α on p38 α, β,γ andδ MAPK" --- p.88 / Chapter 3.7.2 --- Role of TNF-receptor (TNF-R) subtype in the TNF-α-induced p3 8 MAPK expression in C6 cells --- p.89 / Chapter 3.7.3 --- The signaling system mediating TNF-α-induced p38 a MAPK expression in C6 cells --- p.92 / Chapter 3.7.3.1 --- The involvement of PKC in TNF-α-induced p38 MAPK expression in C6 cells --- p.92 / Chapter 3.7.3.2 --- The involvement of PKC in TNF-α-induced p38 MAPK expression in C6 cells --- p.98 / Chapter 3.7.4 --- The relationship between p38 MAPK and β-adrenergic mechanisms in C6 cells --- p.99 / Chapter 3.7.4.1 --- Effects of isoproterenol and propanol on p38 MAPK mRNA levels in C6 cells --- p.103 / Chapter 3.7.4.2 --- Effects of β1-agonist and -antagonist on p38 MAPK mRNA levels in C6 cells --- p.106 / Chapter 3.7.4.3 --- Effects of β2-agonist and -antagonist on p38 MAPK mRNA levels in C6 cells --- p.107 / Chapter 3.8 --- The relationship between p3 8 MAPK and inducible nitric oxide synthase (iNOS) expression --- p.113 / Chapter 3.8.1 --- Effects of TNF-α on the iNOS expression in C6 cells --- p.113 / Chapter 3.8.2 --- Role of TNF-receptors (TNF-R) subtypes in the TNF-α- induced iNOS expression in C6 cells --- p.115 / Chapter 3.8.3 --- The signaling system mediating TNF-α-induced iNOS expression in C6 cells --- p.115 / Chapter 3.8.3.1 --- The involvement of p38 MAPK in the TNF-α-induced iNOS expression in C6 cells --- p.117 / Chapter 3.8.3.2 --- The involvement of PKA in the TNF-α-induced iNOS expression in C6 cells --- p.119 / Chapter 3.9 --- The relationship between p38 MAPK and cAMP-responsive element binding protein (CREB) expression --- p.120 / Chapter 3.9.1 --- Effects of TNF-α on the CREB expression in C6 cells --- p.120 / Chapter 3.9.2 --- Role of TNF-receptors (TNF-R) subtypes in the TNF-α- induced CREB expression in C6 cells --- p.124 / Chapter 3.9.3 --- The signaling system mediating TNF-α-induced CREB expression in C6 cells --- p.126 / Chapter 3.9.3.1 --- The involvement of p38 MAPK in the TNF-α-induced CREB expression in C6 cells --- p.126 / Chapter 3.9.3.2 --- The involvement of PKC in the TNF-α-induced CREB expression in C6 cells --- p.128 / Chapter 3.9.3.3 --- The involvement of PKA in TNF-α-induced CREB expression in C6 cells --- p.129 / Chapter 3.9.4 --- The relationship between CREB and β-adrenergic mechanisms in C6 cells --- p.136 / Chapter 3.9.4.1 --- Effects of isoproterenol and propanol on CREB mRNA levels in C6 cells --- p.136 / Chapter 3.9.4.2 --- Effects of β1-agonist and -antagonist on CREB mRNA levels in C6 cells --- p.139 / Chapter 3.9.4.3 --- Effects of (32-agonist and -antagonist on CREB mRNA levels in C6 cells --- p.142 / Chapter 3.10 --- The relationship between p38 MAPK and transcription factor c-fos expression --- p.146 / Chapter 3.10.1 --- Effects of TNF-α on the c-fos expression in C6 cells --- p.146 / Chapter 3.10.2 --- Role of TNF-receptors (TNF-R) subtypes in the TNF-α- induced c-fos expression in C6 cells --- p.146 / Chapter 3.10.3 --- The signaling system mediating TNF-α-induced c-fos expression in C6 cells --- p.149 / Chapter 3.10.3.1 --- The involvement of p38 MAPK in the TNF-α-induced c-fos expression in C6 cells --- p.149 / Chapter 3.10.3.2 --- The involvement of PKC in the TNF-α-induced c-fos expression in C6 cells --- p.151 / Chapter 3.10.3.3 --- The involvement of PKA in TNF-α-induced c-fos expression in C6 cells --- p.154 / Chapter 3.10.4 --- The relationship between c-fos and β-adrenergic mechanisms in C6 cells --- p.157 / Chapter 3.10.4.1 --- Effects of isoproterenol and propanolol on c-fos mRNA levels in C6 cells --- p.157 / Chapter 3.10.4.2 --- Effects of β1-agonist and -antagonist on c-fos mRNA levels in C6 cells --- p.160 / Chapter 3.10.4.3 --- Effects of β2-agonist and -antagonist on c-fos mRNA levels in C6 cells --- p.164 / Chapter 3.11 --- The relationship between p38 MAPK and transcription factor NF-kB expression --- p.168 / Chapter 3.11.1 --- Effects of TNF-α on the NF-kB expression in C6 cells --- p.168 / Chapter 3.11.2 --- Role of TNF-receptors (TNF-R) subtypes in the TNF-α- induced NF-kB expression in C6 cells --- p.168 / Chapter 3.11.3 --- The signaling system mediating TNF-α-induced NF-kB expression in C6 cells --- p.171 / Chapter 3.11.3.1 --- The involvement of p38 MAPK in the TNF-α-induced NF-kB expression in C6 cells --- p.171 / Chapter 3.11.3.2 --- The involvement of PKC in the TNF-α-induced NF-kB expression in C6 cells --- p.173 / Chapter Chapter 4 --- DISCUSSION AND CONCLUSION / Chapter 4.1 --- Effects of tumor-necrosis factor-alpha (TNF-α) on C6 cell proliferations --- p.176 / Chapter 4.2 --- The Signaling System Involved in TNF-α-Induced p38 MAPK Expression in C6 cells --- p.178 / Chapter 4.3 --- The Signaling System Involved in TNF-α-Induced iNOS Expression in C6 cells --- p.184 / Chapter 4.4 --- The Signaling System Involved in TNF-α-Induced CREB Expression in C6 cells --- p.186 / Chapter 4.5 --- The Signaling System Involved in TNF-α-Induced c-fos Expressionin in C6 cells --- p.190 / Chapter 4.6 --- The Signaling System Involved in TNF-α-Induced NF-kB Expression in C6 cells --- p.193 / Chapter 4.7 --- Conclusions --- p.195 / Chapter 4.8 --- Possible application / References

Mosaic, activating mutations in PIK3CA, the gene encoding the catalytic p110α subunit of class IA phosphatidylinositol 3-kinase (PI3K), are the cause of rare, developmental growth disorders collectively known as PIK3CA-Related Overgrowth Spectrum (PROS). Given the pressing need for targeted therapy and evidence for tissue- and cell lineage-specific distribution of PIK3CA mutations in PROS, developmental models of this disease will be a key asset for preclinical drug testing and for a better understanding of PIK3CA activation in development. This PhD project addressed the lack of human, developmental PROS models by establishing isogenic series of human induced pluripotent stem cells (iPSCs) with endogenously expressed, activating PIK3CA mutations. This involved the optimisation of a CRISPR/Cas9 protocol for efficient knockin of different PIK3CA variants into human iPSCs. An isogenic iPSC series was established with cells expressing either wild-type PIK3CA or PIK3CA-H1047R, knocked into either one or both endogenous alleles. In parallel, mosaic patient- derived fibroblast cultures were reprogrammed to obtain isogenic wild-type and heterozygous iPSCs expressing PIK3CA-E418K. The models were used in comprehensive signalling studies, providing new insights into PI3K signalling in human iPSCs and how it is perturbed by genetic p110α activation. PIK3CA-E418K, a rare variant in both PROS and cancer, caused minimal pathway activation, in contrast to the highly recurrent variant PIK3CA-H1047R which induced strong PI3K signalling in both heterozygous and homozygous iPSCs according to a graded pattern. Studies of clinically relevant PI3K pathway inhibitors provided proof-of-concept that stem cell-based PROS models can be used for preclinical drug testing, and demonstrated that p110α is likely to be the main catalytic isoform mediating canonical PI3K signalling in human iPSCs. Differentiation assays revealed allele dose-dependent effects of PIK3CA-H1047R on stemness, with homozygous iPSCs exhibiting widespread transcriptome remodelling affect- ing genes implicated in cancer and development. Accordingly, these cells showed increased expression of pluripotency genes such as NANOG and NODAL, resulting in self-sustained "stemness" in embryoid body and teratoma assays. In comparison, heterozygous mutants behaved similar to wild-type controls under all differentiation paradigms. Furthermore, evidence was obtained that strong activation of PI3K signalling is fully compatible with definitive endoderm formation, arguing against cell-autonomous differentiation defects as the cause of endoderm sparing in PROS. In summary, these studies demonstrate the utility of human stem cell-based models of PROS for preclinical drug testing and for improved understanding of class IA PI3K signalling in human development. They are also likely to be useful in efforts to obtain a better understanding of PIK3CA-H1047R in human cancer.

Food quality control is a mandatory task in the food industry, and for coffee manufacturers, one of the key target compounds is caffeine, because of its well-known biological effects and currently expensive analytical methods are employed for caffeine quantification. This project was thought with the aim of developing a cost-effective caffeine sensor for application in industrial environments. Two main approaches were investigated: i) the use of imprinted polymers; ii) electrochemical using bare carbon electrodes. Chapter 1 is the main introduction, it focuses on the importance of food quality control, the limitation of the methodologies currently employed and it presents the advantages of using imprinted polymers recognition and electrochemistry signal transduction. Chapter 2 presents data related to studies of self-association of caffeine in water using a novel computational approach. The wider applicability of the method was assessed by studying self-association of paraxanthine and the results were validated via a collaboration with Miss R. Anastasiadi who employed isothermal titration calorimetry. Chapter 3 describes the synthesis of MIPs in water, starting with the selection of the functional monomers: HPTS (8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt). The polymerisation conditions were optimised in terms of solvent to be used, initiator content, temperature and total monomer concentration. Afterwards, the polymers were synthesised, characterised, and preliminary data on the rebinding ability towards caffeine were presented. Chapter 4 focuses on electrochemical methods for the detection of caffeine using bare carbon electrodes. A voltammetric method for accurate determination of caffeine in beverages was developed. Based on the encouraging results obtained, further studies on the applicability of electrochemical methods for coffee quality analysis were done. A second method was developed for simultaneous detection of caffeine and polyphenols and an amperometric chemosensor for sucrose determination was acquired and its applicability for the analysis of green coffee beans was evaluated.

Scaffold proteins facilitate many aspects of intracellular signaling. These proteins can regulate two or more proteins in the same pathway, or coordinate signaling from multiple pathways. Scaffold proteins are therefore key control points for the flux of signaling and play essential roles in biological systems. There are four possible mechanisms by which scaffold proteins achieve activation and propagate signaling: 1) rigid protein binding between two or more proteins to co-localize binding partners, 2) ligand-induced activation such as may result from a conformational change, 3) disorder-to-order transition where the scaffold protein folds as a result of a protein-protein interaction, and 4) dynamic processes such as phosphorylation. The scaffold protein NF-κB essential modulator (NEMO) functions via ligand-induced activation and serves as the key control point for canonical NF-κB signaling. The work described in this thesis investigates the role of a previously uncharacterized domain within NEMO that is required for function, which we term the Intervening Domain (IVD). Bioinformatic analysis reveals a high level of sequence conservation across species within this domain. Conformational changes following ligand binding are observed for NEMO and these changes require conserved sequences in the IVD. Additionally, a functional IVD is shown to increase the binding affinity of NEMO for IKKβ, enhance the thermal stability of NEMO, and is required to propagate NF-κB signaling in cells. A fluorescence-based assay is also developed to characterize the formation of a complex composed of NEMO, a zinc ion, and IκBα. A separate fluorescence-based assay is developed to measure IKK activity and is used to determine that NEMO alone or in the presence of linear tetraubiquitin does not enhance the rate of IKKβ phosphorylation of an IκBα-derived peptide. Furthermore, a number of organic small molecules and macrocycles are screened against the NEMO-IKKβ interaction. One small molecule was validated as an inhibitor and its biophysical properties and inhibition kinetics are described in this thesis. These analyses represent the first characterization of a highly conserved domain required for the function of the key control point in NF-κB signaling. The IVD domain of NEMO could be targeted for development of an allosteric effector for therapeutic discovery.