Chan Ho Yu, Richard. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 115-122). / Abstracts in English and Chinese. / Declaration --- p.i / Acknowledgements --- p.ii / Abstract --- p.iii / 摘要 --- p.v / Table of Contents --- p.vii / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Potassium Channels --- p.1 / Chapter 1.1.1 --- Potassium Ions --- p.1 / Chapter 1.1.2 --- Potassium Channels --- p.1 / Chapter 1.1.3 --- Structure of K Channels --- p.2 / Chapter 1.1.4 --- Classification ofK Channels --- p.3 / Chapter 1.1.5 --- Mechanisms Contributed to K Channel Functions and Diversity --- p.5 / Chapter 1.1.5.1 --- RNA Editing --- p.5 / Chapter 1.1.5.2 --- Alternative Splicing --- p.6 / Chapter 1.1.5.3 --- Heteromultimeric Assembly of Principal Subunits --- p.6 / Chapter 1.1.5.4 --- Auxiliary Subunits --- p.7 / Chapter 1.1.5.5 --- Posttranslational Modifications --- p.7 / Chapter 1.2 --- Voltage-gated Potassium (Kv) Channels --- p.9 / Chapter 1.2.1 --- Diversity of Kv Channel Structure --- p.9 / Chapter 1.2.2 --- Early Origin of the Kv Family --- p.10 / Chapter 1.2.3 --- Structural Diversity of Kv Channels in Drosophila --- p.11 / Chapter 1.2.4 --- Structural Diversity of Kv Channels in Mammals --- p.11 / Chapter 1.2.5 --- Phylogenetic Tree of Kv Family --- p.13 / Chapter 1.2.6 --- Tissue Expression of Kv Channels --- p.13 / Chapter 1.2.7 --- "Three Main Functions of Kv Channels as Signaling Proteins: Ion Permeation, Gating and Sensing" --- p.16 / Chapter 1.2.7.1 --- Ion Permeation --- p.16 / Chapter 1.2.7.2 --- Gating --- p.18 / Chapter 1.2.7.2.1 --- Gating at the S6 Bundle Crossing --- p.18 / Chapter 1.2.7.2.2 --- Ball-and-Chain Gating --- p.19 / Chapter 1.2.7.2.3 --- Gating at the Selectivity Filter --- p.19 / Chapter 1.2.7.3 --- Sensing Mechanisms --- p.20 / Chapter 1.2.7.3.l --- Voltage Sensor --- p.20 / Chapter 1.2.7.3.2 --- Gating Sensors for Ligands --- p.21 / Chapter 1.3 --- KCNA10 --- p.22 / Chapter 1.3.1 --- "Rabbit Homologue of KCNA10, Kcnl" --- p.22 / Chapter 1.3.2 --- Genomic Localization of Human KCNA10 --- p.23 / Chapter 1.3.3 --- Human Gene for KCNA10 --- p.23 / Chapter 1.3.4 --- Basic Kinetic and Pharmacological Properties of KCNA10 --- p.25 / Chapter 1.3.5 --- "Regulation of KCNAlO by KCNA4B, a β -subunit" --- p.27 / Chapter 1.4 --- Aim of the Present Study --- p.30 / Chapter Chapter2: --- Materials and Methods --- p.31 / Chapter 2.1 --- Molecular Sub-Cloning ofKCNAlO --- p.31 / Chapter 2.1.1 --- Polymerase Chain Reaction (PCR) ofKCNA10 Fragment from KCNA Clone --- p.10 / Chapter 2.1.2 --- Separation and Purification of PCR Products --- p.32 / Chapter 2.1.2.1 --- Separation --- p.32 / Chapter 2.1.2.2 --- Purification --- p.33 / Chapter 2.1.3 --- Polishing the Purified PCR Products --- p.33 / Chapter 2.1.4 --- Ligation of PCR Products and pPCR-Script Amp SK(+) Cloning Vector --- p.34 / Chapter 2.1.5 --- Transformation --- p.34 / Chapter 2.1.6 --- Preparing Glycerol Stocks Containing the Bacterial Clones --- p.35 / Chapter 2.1.7 --- Plasmid DNA Preparation --- p.35 / Chapter 2.1.8 --- Clones Confirmation --- p.36 / Chapter 2.1.8.1 --- Restriction Enzyme Digestion --- p.36 / Chapter 2.1.8.2 --- Automatic Sequencing --- p.37 / Chapter 2.2 --- In situ Hybridization --- p.39 / Chapter 2.2.1 --- Probe Preparation --- p.39 / Chapter 2.2.1.1 --- Antisense KCNA10 RNA Probe --- p.39 / Chapter 2.2.1.2 --- Sense KCNA10 RNA Probe (Control Probe) --- p.40 / Chapter 2.2.2 --- Testing of DIG-Labeled RNA Probes --- p.43 / Chapter 2.2.3 --- Paraffin Sections Preparation --- p.43 / Chapter 2.2.4 --- In situ Hybridization: Pretreatment --- p.44 / Chapter 2.2.5 --- "Pre-hybridization, Hybridization and Post-hybridization" --- p.45 / Chapter 2.2.5.1 --- Pre-hybridization --- p.45 / Chapter 2.2.5.2 --- Hybridization --- p.45 / Chapter 2.2.5.3 --- Post-hybridization --- p.46 / Chapter 2.2.6 --- Colourimetnc Detection of Human KCNA10 --- p.46 / Chapter 2.3 --- Cell Culture --- p.47 / Chapter 2.3.1 --- Human Kidney Proximal Epithelial Cell Line (OK) --- p.47 / Chapter 2.3.2 --- Mouse Micro-vessel Endothelial Cell Line (H5V) --- p.48 / Chapter 2.3.3 --- Mouse Neuroblastoma Cell Line (NG108-15) --- p.48 / Chapter 2.3.4 --- Human Bladder Epithelial Cell Line (ECV304) --- p.48 / Chapter 2.3.5 --- Human T Cell Leukemia Cell Line (Jurkat) --- p.49 / Chapter 2.4 --- Total RNA Extraction --- p.49 / Chapter 2.5 --- Reverse Transcription from Cell Line --- p.51 / Chapter 2.6 --- Polymerase Chain Reaction (PCR) ofKCNAl 0 Fragment from Frist Strand cDNA --- p.51 / Chapter 2.7 --- Northern Hybridization --- p.52 / Chapter 2.7.1 --- Probe Preparation --- p.52 / Chapter 2.7.2 --- Separating RNA on an Agarose Gel --- p.52 / Chapter 2.7.3 --- RNA Transfer and Fixation --- p.52 / Chapter 2.7.4 --- Hybridization --- p.54 / Chapter 2.7.5 --- Post-hybridization --- p.54 / Chapter 2.7.6 --- Chemiluminescent Detection --- p.55 / Chapter 2.8 --- Intracellular Free Calcium Ion ([Ca2+］i) Measurement by Confocal Imaging System --- p.56 / Chapter 2.8.1 --- Bathing Solutions --- p.56 / Chapter 2.8.2 --- Preparation of Cells for [Ca2+]i Measurement --- p.56 / Chapter 2.8.3 --- Confocal Imaging System --- p.57 / Chapter 2.8.3.1 --- Fluo-3/AM Dye Loading --- p.57 / Chapter 2.8.3.2 --- [Ca2+]i Measurement --- p.57 / Chapter Chapter3: --- Results --- p.59 / Chapter 3.1 --- Phylogenetic Tree Reconstruction ofKCNAl0 --- p.59 / Chapter 3.2 --- Hydropathy Analysis ofKCNAl0 --- p.60 / Chapter 3.3 --- Molecular Sub-Cloning ofKCNAl0 --- p.61 / Chapter 3.3.1 --- Polymerase Chain Reaction (PCR) ofKCNAl0 Fragment from KCNA10 Clone --- p.61 / Chapter 3.3.2 --- Clones Confirmation --- p.63 / Chapter 3.4 --- In situ Hybridization Analysis ofKCNAl0 mRNAExpression --- p.65 / Chapter 3.4.1 --- Expression ofKCNAl0 in Human Kidney (Nephron) --- p.66 / Chapter 3.4.2 --- Expression ofKCNAl0 in Human Cerebral Artery --- p.69 / Chapter 3.4.3 --- Expression ofKCNAl0 in Human Cerebellum --- p.71 / Chapter 3.4.4 --- Expression ofKCNAl0 in Human Hippocampus --- p.73 / Chapter 3.4.5 --- Expression ofKCNAl0 in Human Occipital Cortex --- p.75 / Chapter 3.4.6 --- Expression ofKCNAl0 in Human Esophagus --- p.77 / Chapter 3.4.7 --- Expression ofKCNAl0 in Human Lung --- p.79 / Chapter 3.4.8 --- Expression ofKCNAl0 in Human Thyroid Glands --- p.81 / Chapter 3.4.9 --- Expression ofKCNAl0 in Human Adrenal Glands --- p.83 / Chapter 3.4.10 --- Expression ofKCNAl0 in Human Spleen --- p.86 / Chapter 3.5 --- RT-PCR ofKCNAl0 Fragment from Different Tissues --- p.88 / Chapter 3.6 --- Northern Blot Analysis of KCNA10 in Different Tissues --- p.90 / Chapter 3.7 --- Effects of Blocking KCNA10 on Ca2+ influx in Human Renal Proximal Tubule Epithelial Cells --- p.91 / Chapter Chapter4: --- Discussion --- p.97 / Chapter 4.1 --- Phylogency ofKCNAlO --- p.97 / Chapter 4.2 --- Hydropathy Plot for KCNA10 --- p.97 / Chapter 4.3 --- Expression ofKCNAl0 --- p.98 / Chapter 4.3.1 --- In situ Hybridization --- p.98 / Chapter 4.3.2 --- RT-PCR & Northern Blot Analysis --- p.99 / Chapter 4.4 --- Functional Implication of KCNA10 Expression in Different Human Tissues --- p.100 / Chapter 4.4.1 --- Unique Functional Properties ofKCNAlO --- p.100 / Chapter 4.4.2 --- Role ofKCNAlO in Renal Proximal Tubule --- p.101 / Chapter 4.4.2.1 --- Functions ofK+ Channels in Kidney --- p.101 / Chapter 4.4.2.2 --- The Function ofKCNAlO --- p.104 / Chapter 4.4.3 --- Role ofKCNAl0 in Blood Vessels --- p.106 / Chapter 4.4.3.1 --- Endothelial Cells --- p.106 / Chapter 4.4.3.2 --- Smooth Muscle Cells --- p.108 / Chapter 4.4.4 --- Role ofKCNA10 in CNS --- p.109 / Chapter 4.4.5 --- Role ofKCNAl0 in Secretory Cells --- p.111 / Chapter 4.4.6 --- Role ofKCNAl0 in Lung --- p.112 / Chapter 4.5 --- Conclusion --- p.114 / Chapter Chapter5： --- Reference --- p.115

An investigation on the damaging effects of potassium acetate deicer (KAc) on concrete durability was conducted. Different SCM replacement levels were used. ASTM C 1293 and ASTM C 1260 test methods results indicated that KAc is capable of inducing alkali-silica reaction (ASR) expansion in specimens containing reactive aggregate. Class C fly ash was ineffective even at a replacement level of 45%. Class F fly ash and slag were effective in mitigating ASR expansion for specimens exposed to diluted (25% by weight) KAc. KAc showed an increase in pH value upon exposure to concrete specimens. Concrete specimen without SCM and exposed to deicers had higher [K]/[Na] molar ratio near the surface but ions penetrated less compared to specimens containing SCM. ASTM C 666 and MTO LS-412 test methods results showed that air-entrained concrete slabs and prisms without SCM and exposed to KAc are resistant to scaling and freezing and thawing damage.

An investigation on the damaging effects of potassium acetate deicer (KAc) on concrete durability was conducted. Different SCM replacement levels were used. ASTM C 1293 and ASTM C 1260 test methods results indicated that KAc is capable of inducing alkali-silica reaction (ASR) expansion in specimens containing reactive aggregate. Class C fly ash was ineffective even at a replacement level of 45%. Class F fly ash and slag were effective in mitigating ASR expansion for specimens exposed to diluted (25% by weight) KAc. KAc showed an increase in pH value upon exposure to concrete specimens. Concrete specimen without SCM and exposed to deicers had higher [K]/[Na] molar ratio near the surface but ions penetrated less compared to specimens containing SCM. ASTM C 666 and MTO LS-412 test methods results showed that air-entrained concrete slabs and prisms without SCM and exposed to KAc are resistant to scaling and freezing and thawing damage.

Thesis (M. Ag. Sci.)--University of Adelaide, 1959. / Typewritten. Includes bibliographical references.

Thèses (M.Sc.)--Université de Sherbrooke (Canada), 1997. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.

Th. 3e cycle--Chim. struct.--Besançon, 1977. N°: 279.

Made available in DSpace on 2014-10-09T12:29:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:18Z (GMT). No. of bitstreams: 1 00509.pdf: 1593088 bytes, checksum: f571f25ac5f3585305e9bcb409db3f29 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA

Made available in DSpace on 2014-10-09T12:29:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:18Z (GMT). No. of bitstreams: 1 00509.pdf: 1593088 bytes, checksum: f571f25ac5f3585305e9bcb409db3f29 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA

Les cellules gliales, notamment les astrocytes, interviennent dans l'homéostasie potassique en limitant entre autres les excès de potassium dans le milieu extracellulaire. C'est le tamponnage potassique glial. Les canaux gliaux Kir4.1, principaux responsables de la haute conductance potassique de ces cellules au potentiel de repos, semblent être les candidats idéaux pour assurer un rôle important dans le tamponnage potassique. Cependant, leur contribution effective et l'importance de cette participation dans la recapture de potassium sont encore peu claires. Notre étude s'est appuyée sur le modèle de la souris transgénique knock-out pour le gène Kir4.1 dans les cellules gliales GFAP+ (cKG: knock-out conditionnel). Le but principal était d'étudier l'impact de cette déplétion génétique sur la recapture du potassium extracellulaire. Les expériences ont été faites in vivo dans l'hippocampe de souris juvéniles, maintenues sous anesthésie (kétamine-xylasine). Nous avons utilisé des pipettes sensibles au potassium pour enregistrer les variations de concentration de potassium extracellulaire ([K+]extra), simultanément avec des enregistrements de potentiels de champ DC. Nous avons évalué les différences de dynamisme du [K+]extra suite à des stimulations (chapitre 1) ou lors de l'activité spontanée hippocampique, caractérisée par de lents épisodes périodiques d'activité, occasionnant de conséquentes augmentations de [K+]extra (~ 0.5 mM) (chapitre 2). En parallèle, nous avons aussi effectué des enregistrements intracellulaires gliaux (chapitre 1) pour évaluer l'effet de la déplétion sur leurs propriétés membranaires. Nous avons mis en évidence que les souris cKG Kir4.1: 1) présentaient des glies dépolarisées de près de 20 m V, avec une perméabilité potassique altérée; 2) présentaient un retour plus lent du [K+]extra suite des stimulations induisant un excès modéré de [K+]extra <2mM), ou suite à l'activité spontanée lente hippocampique ; 3) présentait une activité spontanée moins intense, associée à un dynamisme de [K+]extra plus lent. Nous montrons donc dans cette étude que les canaux Kir4.1 gliaux confèrent une importante conductance potassique aux cellules gliales, et par conséquent ont un rôle essentiel dans le maintien du potentiel de membrane des cellules gliales proche du potentiel d'équilibre du potassium. De plus, nous apportons des évidences en faveur de l'implication de ces canaux dans une recapture efficace du potassium extracellulaire.

M. S.