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1	Indukovaná RNAi proti esenciálním genům metabolismu dusíku jako nástroj pro kontrolu GM rostlin / Inducible RNAi against essential genes of nitrogen metabolism as a tool for control of GM plants Kobercová, Eliška January 2017 (has links) Uncontrolled spreading of genetically modified (GM) plants is one of the main concerns about their cultivation. Inducible RNA interference against an essential gene could be a tool for control of GM plants. After spraying with a chemical inducer, the essential gene will be silenced so the treated GM plant will die. For testing this strategy we chose two key enzymes of nitrogen metabolism, glutamate synthase (GOGAT) and glutamine synthetase (GS). GS processes ammonium ions into glutamine, then GOGAT transfers the amide group from glutamine to 2-oxoglutarate to form two glutamates. GS/GOGAT cycle is the main pathway for assimilation of ammonium ions, which could be toxic to plants in a higher concentration. Disruption of ammonium assimilation during photorespiration causes a strong inhibition of photosynthesis. The aim of this work was to describe the effects of silencing GOGAT and GS genes in Arabidopsis thaliana. To induce silencing, RNAi hairpin constructs under a control of constitutive or estradiol-inducible promoter were prepared. In selected independent transformants with the inducible hairpin against GOGAT, chlorosis and reduced growth were observed after the estradiol treatment in in vitro conditions. However, the spraying with estradiol was tricky, at the whole plant level, the induction of...
2	Advanced Modeling of Longitudinal Spectroscopy Data Kundu, Madan Gopal January 2014 (has links) Indiana University-Purdue University Indianapolis (IUPUI) / Magnetic resonance (MR) spectroscopy is a neuroimaging technique. It is widely used to quantify the concentration of important metabolites in a brain tissue. Imbalance in concentration of brain metabolites has been found to be associated with development of neurological impairment. There has been increasing trend of using MR spectroscopy as a diagnosis tool for neurological disorders. We established statistical methodology to analyze data obtained from the MR spectroscopy in the context of the HIV associated neurological disorder. First, we have developed novel methodology to study the association of marker of neurological disorder with MR spectrum from brain and how this association evolves with time. The entire problem fits into the framework of scalar-on-function regression model with individual spectrum being the functional predictor. We have extended one of the existing cross-sectional scalar-on-function regression techniques to longitudinal set-up. Advantage of proposed method includes: 1) ability to model flexible time-varying association between response and functional predictor and (2) ability to incorporate prior information. Second part of research attempts to study the influence of the clinical and demographic factors on the progression of brain metabolites over time. In order to understand the influence of these factors in fully non-parametric way, we proposed LongCART algorithm to construct regression tree with longitudinal data. Such a regression tree helps to identify smaller subpopulations (characterized by baseline factors) with differential longitudinal profile and hence helps us to identify influence of baseline factors. Advantage of LongCART algorithm includes: (1) it maintains of type-I error in determining best split, (2) substantially reduces computation time and (2) applicable even observations are taken at subject-specific time-points. Finally, we carried out an in-depth analysis of longitudinal changes in the brain metabolite concentrations in three brain regions, namely, white matter, gray matter and basal ganglia in chronically infected HIV patients enrolled in HIV Neuroimaging Consortium study. We studied the influence of important baseline factors (clinical and demographic) on these longitudinal profiles of brain metabolites using LongCART algorithm in order to identify subgroup of patients at higher risk of neurological impairment. / Partial research support was provided by the National Institutes of Health grants U01-MH083545, R01-CA126205 and U01-CA086368 Spectroscopy Functional Data Analysis Longitudinal Functional Data Analysis Brownian Bridge Longitudinal CART Longitudinal Regression Tree HIV Brain metabolites HIV neuroimaging consortium LongPEER PEER Decomposition based penalty NAA Creatine Myo-inositol Choline Glutamine and Glutamate White matter Gray matter Basal ganglia LongCART neurological disorder Global deficit score GSVD General Singular Value Decomposition Microbial metabolites -- Research HIV infections -- Complications Myelinated neurofibrils Research -- Methodology Trees (Graph theory) -- Research Biometry -- Research -- Methodology Cerebral cortex Central nervous system -- Abnormalities Spectrum analysis -- Research HIV (Viruses) -- Research -- Analysis Creatine Choline Glutamine

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Indukovaná RNAi proti esenciálním genům metabolismu dusíku jako nástroj pro kontrolu GM rostlin / Inducible RNAi against essential genes of nitrogen metabolism as a tool for control of GM plants

Advanced Modeling of Longitudinal Spectroscopy Data