Asymmetries in physisorbed systems give rise to interesting phases and phase transitions in two-dimensional (2D) monolayer and multilayer systems. The effects of asymmetric adsorbate and substrate interactions in monolayers of dipolar molecules on ionic substrates and N2 on graphite are studied. In the case of dipolar molecules on ionic substrates, 2D dielectric phase transitions using a modified Blume-Emery-Griffiths (BEG) model are determined theoretically. A dipole adsorbed vertically above a metal ion lattice site, and pointing up (down), is assigned a spin s=+1 (s=-1). An empty lattice site is assigned a spin S=0. Analytic solutions for both ferroelectrically and antiferroelectrically ordered systems are found. The model is applied to CO adsorbed on MgO and NaCl, and preliminary results for the phase diagram of CH3F on NaCl, are presented. Multilayer phase transitions for N2 on graphite are studied experimentally using synchrotron x-ray diffraction. The system is measured to undergo layering transitions, where the number of layers increases as the temperature of the system increases. A new multilayer phase diagram based on our results and the combined results published by other researchers is presented. The effects of capillary condensation on this multilayer system are quantified, and it is determined that its primary effect is to broaden the discrete layering transitions. The results for both studies are put into context with other adsorption systems with asymmetric interactions.

The usual procedure employed in enzyme kinetic analysis is the method of initial rates. However, it has been appreciated for years that the analysis of enzyme-catalyzed reactions could, in principle, be more efficiently performed by examining the entire time course. There is much more information contained in a progress curve than in a simple initial rate. With the appearance of the computer, the formidable computations necessary for the use of integrated-rate equations are quite possible. The intention of this research was to develop the analytical and statistical methodology for applying an integrated-rate equation to a two-substrate reaction. I have analyzed the kinetics of pyruvate reduction, as catalyzed by the rabbit M4 isoenzyme of lactate dehydrogenase. Time courses were carried out, in sextuplicate, by observing the disappearance of NADH. Initial concentrations were: NADH, .026 to 1.7 mM; pyruvate, .016 to .29 mM; NAD+, 0 to 7 mM; and lactate, 0 to 40 mM. The concentrations of pyruvate and/or NAO+ were such that measurable enzyme inactivation did not occur. For each progress curve, values of Cf, Cs, C1, and C2 in the integrated equation were obtained by nonlinear regression; variances were calculated using replicate observations. Multiple regression, weighting each coefficient according to its variance, then gave 8 of the 11 J coefficients that characterize an ordered ternary-complex mechanism. The values obtained are comparable to previously published initial-rate values and predict progress curves that are consistent with the observed curves. The analysis required as few as nine experiments. A similar initial-rate study would require perhaps 10 times this number. This research shows that the computations necessary to apply progress curve methods can be routinely computerized; these methods are potentially a very powerful tool when used with the correct analytical techniques and experimental design.

A fundamental understanding of bio-interfaces will facilitate improvement in the design and application of biomaterials that can beneficially interact with biological objects such as nucleic acids, molecules, bacteria, and mammalian cells. Currently, there exist analytical instruments to investigate material properties and report information on electrical, chemical, physical, and mechanical natures of biomaterials and biological samples. The overall goal of this research was to utilize advanced spectroscopy techniques coupled with data mining to elucidate specific characteristic properties for biological objects and how these properties imply interaction with environmental biomaterials. My studies of interfacial electron transfer (ET) of DNA-modified gold electrodes aided in understanding that DNA surface density is related to the step-wise order of which a self-assembled monolayer is created on a gold substrate. Further surface modification plays a role in surface conductivity, and I found that electro-oxidation of the DNA involved the oxidation of guanine and adenine nucleotides. Scanning tunneling microscopy (STM) was used to create topography and current images of the SAM surfaces. I also used Raman microspectroscopy (RM) to obtain spectra and spectral maps of DNA-modified gold surfaces. For studies of bacteria, atomic force microscopy (AFM) and scanning electron microscopy (SEM) images showed similar morphological features of Gram-positive and Gram-negative bacteria. Direct classical least squares (DCLS) analysis aided to distinguish co-cultured strains. Fourier transform infrared (FTIR) spectroscopy proved insightful for characteristic bands for Gram-positive bacteria and a combined AFM/RM image revealed a relationship between culture height/density and peak Raman intensity. In our mammalian cell studies we focused on human lung adenocarcinoma epithelial cells (A549), metastatic human breast carcinoma cells MDA-MB-435 (435), and non-metastatic MDA-MB-435/BRMS1 (435/BRMS1). RM revealed similarities between metastatic 435 and non-metastatic 435/BRMS1 cells compared to epithelial A549 cells. AFM showed increases in biomechanical properties for 435/BRMS1 in the areas of cell adhesion, cell spring constant, and Young’s modulus. Fluorescent staining illustrates F-actin rearrangement for 435 and 435/BRMS1. Electric cell-substrate impedance sensing (ECIS) revealed that 435 cells adhere tightly to substrata and migrate rapidly compared with 435/BRMS1. For ECIS, ≤10-fold diesel exhaust particles (DEP) concentration exposure caused clastogenic DNA degradation whereas ≥25-fold DEP exposure caused cytotoxic results. Resveratrol (RES) at 10 μM showed minimal to mild protection against DEP before and after exposure and aided in improving injury recovery.

Indiana University-Purdue University Indianapolis (IUPUI) / Neurofibromatosis Type 1 (NF1) is a highly penetrant autosomal dominant genetic disorder where mutations in the tumor suppressor gene NF1 leads to decreased neurofibromin. The most debilitating manifestation is the presence of complex multilineage Schwann cell-derived plexiform neurofibromas (PN). Historically, little clinical success has been achieved targeting PN through surgery or chemotherapies. I performed an shRNA library screen of patient-derived Schwann cell lines to identify novel therapeutic targets to disrupt PN formation and progression. An shRNA library screen of human kinases and Rho-GTPases was performed in NF1-/- and paired NF1 competent immortalized Schwann cell lines. Following sequencing, candidates were identified. We previously developed a novel mouse model of NF1 wherein a neural crest specific Postncre targeted loxp-flanked Nf1 that replicated the PN found in patients. Additional cohorts of mice were generated with biallelic deletion of Rac1 (Nf1f/fRac1f/f Postn-Cre+; DKO ). Mice were aged for 9 months and peripheral nerves were harvested and fixed in formalin. Peripheral nerve size was measured and tumors were identified through blinded analysis of hematoxylin and eosin and Masson’s Trichrome (collagen) stained slides. Rho family members, including RAC1, were identified as candidates through an shRNA library screen. Genetic disruption of Rac1 in the Schwann cell lineage resulted in the prevention of tumor formation in DKO mice, as observed by peripheral nerve size and histological analysis. I observed an average of 14.8 +/- 2.65 tumors per mouse in the Nf1f/f Postnviii Cre+ cohort compared to 0 tumors in the DKO (p<0.0001). Following an shRNA library screen, RAC1 was identified as a candidate to modulate PN formation. Biallelic deletion of Rac1 in vivo prevented PN formation. I demonstrate that a candidate identified in an shRNA library screen can translate to an biological effect in a mouse model of PN.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18331号 / 農博第2056号 / 新制||農||1022(附属図書館) / 学位論文||H26||N4838(農学部図書室) / 31189 / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 植田 充美, 教授 三上 文三, 教授 小川 順 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18342号 / 農博第2067号 / 新制||農||1024(附属図書館) / 学位論文||H26||N4849(農学部図書室) / 31200 / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 栗原 達夫, 教授 三上 文三, 教授 平竹 潤 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19042号 / 農博第2120号 / 新制||農||1032(附属図書館) / 学位論文||H27||N4924(農学部図書室) / 31993 / 京都大学大学院農学研究科食品生物科学専攻 / (主査)教授 伏木 亨, 教授 保川 清, 教授 金本 龍平 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

京都大学 / 0048 / 新制・課程博士 / 博士(薬科学) / 甲第18918号 / 薬科博第32号 / 新制||薬||4(附属図書館) / 31869 / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 松﨑 勝巳, 教授 加藤 博章, 教授 石濱 泰 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DGAM

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20701号 / 工博第4398号 / 新制||工||1683(附属図書館) / 京都大学大学院工学研究科マイクロエンジニアリング専攻 / (主査)教授 小寺 秀俊, 教授 中部 主敬, 教授 安達 泰治, 准教授 横川 隆司 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

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