by Wong Chi Shing Micky. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 140-149). / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- The Uterine Cervix --- p.1 / Chapter 1.2 --- Cervical Secretion and its Function --- p.3 / Chapter 1.3 --- Ion Transport System in Cell Volume Regulation --- p.6 / Chapter 1.3.1 --- "Regulatory Volume Decrease, RVD" --- p.8 / Chapter 1.3.2 --- "Regulatory Volume Increase, RVI" --- p.8 / Chapter 1.4 --- Signaling Pathways underlying RVD and RVI - The Role of Intracellular Free Calcium --- p.11 / Chapter 1.5 --- Swelling-induced Cl- Current --- p.12 / Chapter 1.6 --- Ca2+ activated K+ Channel --- p.14 / Chapter 1.7 --- Objectives of the Study --- p.15 / Chapter Chapter 2. --- Materials and Methods --- p.17 / Chapter 2.1 --- Materials --- p.17 / Chapter 2.1.1 --- Culture Media --- p.17 / Chapter 2.1.2 --- Chemicals --- p.17 / Chapter 2.2 --- Preparation of Solutions --- p.18 / Chapter 2.3 --- Cell Culture --- p.21 / Chapter 2.4 --- Patch-clamp Technique --- p.22 / Chapter 2.4.1 --- Preparation of Electrode --- p.27 / Chapter 2.4.1.1 --- Pulling and Polishing of Electrode --- p.27 / Chapter 2.4.1.2 --- Filling of the Electrode --- p.27 / Chapter 2.4.1.3 --- Coating of Electrode --- p.28 / Chapter 2.4.2 --- Patch-clamp Study --- p.29 / Chapter 2.4.2.1 --- Formation of Whole-cell Configuration --- p.29 / Chapter 2.4.2.2 --- Data Acquisition and Analysis --- p.31 / Chapter 2.5 --- Study of Cellular Volume Regulation by Confocal Laser Scanning Microscopy (CLSM) --- p.35 / Chapter 2.6 --- Determination of Intracellular Ca2+ by Confocal Laser Scanning Microscopy (CLSM) --- p.38 / Chapter Chapter 3. --- Results --- p.39 / Chapter 3.1 --- "Regulatory Volume Decrease, RVD" --- p.39 / Chapter 3.2 --- Responses of [Ca2+］i to swelling --- p.47 / Chapter 3.3 --- KC1 Efflux in RVD in HeLa Cells --- p.57 / Chapter 3.4 --- Swelling-induced Cl- Current --- p.67 / Chapter 3.4.1 --- Swelling-induced Anion and Cation Current --- p.67 / Chapter 3.4.2 --- Ca2+-independence of Swelling-induced Cl- Current --- p.71 / Chapter 3.4.3 --- Effect of Cl- Channel Blockers on Swelling-induced Cl- Current --- p.75 / Chapter 3.4.4 --- Anion Selectivity of Swelling-induced Cl- Current --- p.85 / Chapter 3.4.5 --- Cl- Dependence of Swelling-induced Cation Conductance --- p.85 / Chapter 3.4.6 --- K+ Independence of Swelling-induced Anion Conductance --- p.95 / Chapter 3.5 --- Ca2+ Activated K+ Current --- p.101 / Chapter 3.5.1 --- Ionomycin Induced Cell Shrinkage under Isotonic Condition --- p.101 / Chapter 3.5.2 --- Ionomycin Stimulated a Whole-cell K+ Conductance --- p.101 / Chapter 3.5.3 --- The Effect of Ionomycin on Intracellular Ca2+ Level --- p.111 / Chapter 3.5.4 --- Ca2+ Dependence of Ionomycin Stimulated K+ Current --- p.111 / Chapter Chapter 4. --- Discussion --- p.124 / Regulatory Volume Decrease in HeLa Cells --- p.124 / Role of Calcium in Regulatory Volume Decrease (RVD) --- p.126 / Swelling-induced Cation and Anion Conductance --- p.128 / Ca2+ Activated K+ Current in HeLa Cells --- p.134 / Chapter Chapter 5. --- Reference --- p.140

Thesis (Ph. D.)--University of Wisconsin--Madison, 1966. / Typescript. Vita. Description based on print version record. Includes bibliographical references.

This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).

<p> This thesis is a study of the adhesive behaviour of HeLa cells using a novel instrument designed for measuring both the shearing and compression force applied to the cells. For these experiments a micropipette forged as a double cantilever is used to grasp and manoeuvre a cell onto a silicon or Poly-L-Lysine (PLL) coated substrate. The substrate is then moved perpendicularly with respect to the micropipette tip thereby sliding and shearing the cell across the surface. The perpendicular and parallel deflection of the cantilever enables us to directly measure the friction and normal force. A new approach for calibrating both sections of the cantilever has been developped and will also be presented in this work. As a proof of concept, the experiment is also performed with a polystyrene bead. The polystyrene bead, a simpler system, manifests some of the typical results expected from friction experiments. </p> / Thesis / Master of Science (MSc)

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.

published_or_final_version / Biological Sciences / Master / Master of Philosophy

Gene expression at the level of mRNA translation is critical for cells to respond to external signals; it allows changes in protein synthesis without triggering transcription of a new set of genes. Control of mRNA translation and stability is important in several cellular processes including cell growth and differentiation. Thus regulation of the cellular machinery involved in mRNA translation is crucial. Poly (A) binding protein (PABP1), eukaryotic elongation factor 1A (eEF1A) and ribosomal protein S6 (RPS6) are important members of the cellular mRNA translation machinery, the mRNAs that encode these proteins belong to the terminal oligo pyrimidine tract (TOP) containing family. Translation of the TOP mRNAs is regulated by growth signals and usually codes for several proteins involved in mRNA translation. Our laboratory has previously reported up regulation of PABP1 mRNA translation during recovery from heat shock. It was also shown that the terminal oligopyrmidine tract (TOP) cis-element of PABP1 mRNA is responsible for the preferential increase of PABP1 mRNA translation; however the mechanism for achieving this is unknown. In the studies reported here, we showed that translation of eEF1A and RPS6 expression was similarly enhanced during recovery from heat shock. Analyses of samples of in vivo cross linked RNA– protein complexes, immunoprecipitated by ZNF9 antibody, for the presence of specific mRNAs showed that the cellular nucleic acid binding protein ZNF9 binds not only to TOP mRNAs but also mRNA that lack the TOP element such as to β-actin mRNA. To elucidate the mechanism of activation of TOP mRNA translation, as a candidate trans acting factor, siRNA was used to deplete the cellular level of ZNF9 from heat shocked HeLa cells to examine its potential role in stimulation of TOP mRNA translation during recovery from heat shock. Results show that the knock down of ZNF9 disallowed the preferred stimulation of PABP1, eEF1A and RPS6 expression during recovery from heat shock. There was no detectable effect on the constitutive expression of either β-actin or PABP1, eEF1A and RPS6 in exponentially growing HeLa cells. These results suggest that binding of ZNF9 to TOP mRNAs per se does not inhibit translation, but more likely it acts as a general facilitator of mRNA translation. It is possible that modification of the interaction between ZNF9 with other unknown protein factors is responsible for its preferred effect on all three TOP mRNAs studied here. Additionally, results also suggest that a different TOP sequences amongst the observed TOP mRNAs responds similarly to ZNF9.

The correction of human genetic disorders by transfer of genetic material to cells is under intensive investigation in a number of 1aboratories. One possible way of trying to achieve the transfer of nucleic acid is by attaching DNA to a protein which has specific receptors on cells and which undergoes receptor-mediated endocytosis. In order to make use of the ligand protein-receptor approach for DNA transfer, iron-loaded human serum transferrin has been modified with the water soluble carbodiimides N-ethy1-N I -(3-dilllethy1aminopropyl) carbodiimide (CDI) and its quaterary analogue (ECDI) to give modified N-acy1urea transferrins. N-Acy1urea CDI (Fe 3+) transferrin and N-acy1urea CDI (Fe ) transferrin have been found to interact with and bind DNA in a reversible manner which i! dependent on ionic strength. [1251] N-Acy1urea CDI+(Fe3+) transferrin binds to transferrin receptors on Hea cells in culture and undergoes internalization through receptor-mediated endocytosis. Binding of the modified transferrin in the presence of calf thymus DNA to transferrin receptors also takes place. However, although internalization in the presence of DNA doe! appear to take place, the results of the internalization are not fully understood. Transfection studies with N-acy1urea CDI (Fe ) transferrin and plasmid pBR322 DNA as well as plasmid ptkNEO DNA complexes in the HeLa cell system are reported. The results of a number of transfection experiments suggests that N-acy1urea transferrins are capable of transfecting DNA (ptkNEO DNA), carrying genes for resistance to the antibiotic Geneticin (G41S) in the HeLa cell system. However, further development of the transfection system is necessary in order that consistantly reproducible results may be achievd. / Thesis (M.Sc.)-University of Durban-Westville, 1986.

Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 100-109) Also available in print.