Thesis (Ph. D.)--Michigan State University. Dept. of Chemistry, 2006. / Title from PDF t.p. (viewed on Nov. 20, 2008) Includes bibliographical references. Also issued in print.

Würzburg, Universiẗat, Diss., 2008.

Zugl.: Berlin, Univ., Diss., 2005 / Hergestellt on demand

No description available.

Made available in DSpace on 2018-08-02T00:16:18Z (GMT). No. of bitstreams: 1 tese_4383_Dissertação - Gabriela Pessotti Zamperlini.pdf: 3129526 bytes, checksum: 3a74e78e2de0c895848b0c1b69e39a81 (MD5) Previous issue date: 2010-03-23 / RESUMO - No intuito de ampliar o conhecimento sobre a cultura do abacaxizeiro, em particular da cultivar Vitória, um híbrido resistente à fusariose, este trabalho avaliou o crescimento e o desempenho fotossintético de plantas cultivadas na Fazenda Experimental do Incaper em Sooretama, Estado do Espírito Santo. Em um delineamento experimental inteiramente casualizado, a altura da planta e o comprimento da folha D, os teores de pigmentos fotossintéticos e a eficiência fotoquímica foram monitorados, desde o estádio de muda até o final do estádio reprodutivo. As plantas da cv. Vitória apresentaram menor porte do que os abacaxizeiros das cultivares Pérola e Smooth Cayenne, que são as mais produzidas no Brasil. O teor de pigmentos fotossintéticos (clorofilas a e b e carotenóides) aumentou durante o estádio vegetativo e manteve-se estável até o último mês de análise, quando sofreu uma redução. A análise da fluorescência transiente mostrou um aumento na densidade de centros de reação ativos do fotossistema II (RC/ABS), na força das reações fotoquímicas (P0/(1-P0)), na força relacionada às reações após a redução de QA- (0/(1-0)), e na performance das reações de óxido-redução no fotossistema I (R0/(1-R0)) durante o estádio vegetativo, que resultou no aumento do índice de vitalidade (PIABS) e do índice de vitalidade total (PITOTAL) das plantas ao final do período vegetativo. Estes índices apresentaram redução em seus valores três semanas após a indução floral, indicando uma inibição da fotossíntese, que evidencia uma sensibilidade das plantas à indução. Porém, os abacaxizeiros Vitória parecem apresentar mecanismos eficientes de diminuição dos danos ao aparato fotoquímico, visto que houve uma recuperação em RC/ABS, P0/(1-P0) e 0/(1-0) durante o período reprodutivo. Estes resultados permitem inferir que os índices de desempenho fotoquímico (PIABS e PITOTAL) foram parâmetros sensíveis à indução floral, mostrando-se eficientes na detecção de mudanças fisiológicas ocorridas durante o estádio vegetativo e reprodutivo das plantas de abacaxizeiro Vitória.

An in vitro phagocytosis assay system was developed and characterized for studying the specific receptor-mediated phagocytosis of bovine ROS by bovine RPE cells. The phagocytosis of ROS was detected qualitatively by electron microscopy and quantitatively by treating RPE cells with radioiodinated ROS or by probing ROS-treated RPE cells with a radiolabeled antirhodopsin monoclonal antibody. The binding sites for various antirhodopsin monoclonal antibodies were localized as an essential step in their application as immunochemical probes for analysis of the structure and function of rhodopsin. Five monoclonal antibodies raised against rhodopsin have been shown to be directed against the N-terminal regions on the basis of their reactivity to an immunoaffinity purified 2-39 glycopeptide, a 2-16 tryptic glycopeptide and a 1-16 synthetic peptide as measured by radioimmune competition assays. Limited proteolysis, immunogold-dextran labeling and competitive inhibition studies identified two antirhodopsin monoclonal antibodies which bound to internal cytoplasmic loop regions of rhodopsin. Finally, the binding sites for these and other C-terminal specific antirhodopsin monoclonal antibodies were used to elucidate the proposed transmembrane helical model of rhodopsin. An antirhodopsin monoclonal antibody (rho 4D2), which bound to rhodopsin in glutaraldehyde-fixed ROS plasma membranes, was employed as an immunocytochemical probe in studying the possible role of rhodopsin in the binding and phagocytosis of rod outer segments. An immunoaffinity purified 2-39 N-terminal rhodopsin glycopeptide, a synthetic 1-16 peptide analogue of rhodopsin and phospholipid vesicles reconstituted with rhodopsin were all found to be ineffective in inhibiting the phagocytosis of ¹²⁵I-labeled ROS by RPE cells. In essence, these results provided compelling evidence that rhodopsin in the ROS plasma membrane does not function as the ligand for recognition by RPE cells. The molecular properties of the ROS cell surface ligand(s), which are involved in recognition by bovine RPE cells, were studied by limited-proteolytic digestion in conjunction with quantitative phagocytosis assays. Mildly trypsin-treated ROS were found to be less effectively phagocytized than untreated ROS by bovine RPE cells. Moreover, the glycopolypeptides (34kD and 24kD) released from the ROS cell surface by trypsin were capable of inhibiting ROS phagocytosis. The ROS plasma membrane specific, ricin-binding, 230kD glycoprotein was observed by SDS-gel electrophoresis and western blotting to be highly trypsin sensitive under these conditions. Hence, ricin affinity chromatography and immunoaffinity chromatography were employed in an attempt to purify this 230kD glycoprotein from ROS membranes. Enriched preparations of the 230kD glycoprotein were reconstituted into phospholipid vesicles and effectively used to inhibit the phagocytosis of ROS by RPE cells. In summary, a ROS plasma membrane specific, 230kD glycoprotein has been identified and isolated; this protein may act as a ligand in specific ligand-receptor interactions between ROS and RPE cells. / Medicine, Faculty of / Biochemistry and Molecular Biology, Department of / Graduate

Måleri är centralt i mitt arbete. Jag har utövat måleri så länge jag har praktiserat konst. Sedan december 2017 har jag tillverkat egna färgpigment ur naturmaterial och uteslutit fabrikstillverkad färg från mitt måleri. Processen har hjälpt mig inse att all färg innehåller historia och plats. Genom att skriva om platserna där jag utför konstnärligt arbete, specifikt ateljén, fältet och utställningen, hoppas jag belysa viktiga aspekter inom min praktik.

Indiana University-Purdue University Indianapolis (IUPUI) / Obesity is a medical condition whose rates have seen a rise in both the United States and worldwide in recent decades. Numerous studies have been done to understand obesity, and through the use of GWAS researchers have been able to find multiple genetic factors that can contribute to obesity in mammals. One proposed cause of obesity are genetic impacts on cilia formation in the CNS, which causes downstream effects on food intake and energy expenditure, causing obesity via overeating and decreased activity. In the first half of this thesis, I describe a study, in collaboration with the Berbari Lab at IUPUI, that explored the human chromosome 16:53801550-53808600 (GRCh37/hg19), an intron of the FTO alpha-ketoglutarate Dependent Dioxygenase (FTO) gene for transcriptional regulators that impact BMI and obesity. First, using control DNA, PCR, and gel-electrophoresis, we created an assay for 44 primer sets (forward and reverse) covering the genomic region. After optimizing the assay, we then selected 111 human DNA samples across three weight groups (underweight, normal weight, and obese) to sequence using the assay. The samples were selected from subjects enrolled in the Walsh Lab FDP study. Sequencing was completed using the Illumina MiSeq System, and sequenced results were viewed using the Integrative Genomics Viewer (IGV) program. Variants that showed in the results were analyzed across and within the weight groups, and their locations were researched for previously known BMI or enhancer activity using online genome browsers Ensembl and UCSC Genome Browser. The results of this study revealed two SNPs, rs8055197 and rs11642015, that provided the best correlation with the weight categories among the samples. These results were consistent with literature that previously linked these single-nucleotide polymorphisms (SNPs) to obesity, particularly in relation to genes that are regulated by FTO (CUX1, POMC, and IRX3/5). Both SNPs lie within areas that show high enhancer activity in neural crest cells, important cells for cilia formation. Although there were SNPs in high LD within both regions, these two SNPs were chosen due to their homologous variant locations within the mouse genome (rs8055197 - GRCm38/mm10 8:91376305; rs11642015 - GRCm38/mm10 8:91375651), which provides a means of testing this obesity correlation, with a proposed enhancer relationship through FTO, in mouse models. In the second half of this thesis, I explored new methods for quantitatively defining natural hair color categories, and attempted to find novel SNPs impacting hair color in a GWAS using the quantitative values as phenotypes. In previous publications, the development and validation of the HIrisPlex-S Prediction Tool for hair prediction was made using categorical hair colors, which were defined and classified by individual researchers or lab personnel. Using spectrophotometer measurements and HSV color values, we used a machine-learning tool to objectively classify sample hair photos into natural hair color classes. We then used this quantitative data as the input phenotype for a GWAS, using both linear regression and linear mixed model regression, to search for new genetic associations with these objectively defined hair color classes. Lastly, we also measured correlations between these hair color phenotypes and a SNP array consisting of all currently known pigment SNPs cited in recent literature. The results of this study showed that quantitative values can be used as a means of classifying human hair colors. Both models used in the GWAS highlighted previously known SNPs that contributed to quantitative hair color. By utilizing the linear mixed model approach which has the ability to generate more power due to the normalization of hidden population structure, there was one near genome-wide significant SNP found that is currently not linked with hair color, rs2037697 (IQUB), which showed strong associations with light brown hair (p-value = 1.83192E-07), however this would need to be confirmed with increased numbers to validate its association. The results of the correlation analysis showed that SNPs cited as having impacts on pigmentation (eye, skin, and hair) also show strong associations with these objectively defined quantitative hair color classes and these rankings may prove very useful as the field moves towards quantitative hair color prediction.

The pigment-lipid complexes of the phytopathogen, Xanthomonas juglandis, were studied. Experiments were designed to determine the cellular location of the complexes and whether or not they are associated with protein.

A sporadic pink color development in cooked, uncured turkey products remains a problem within the poultry industry because consumers associate this defect with inadequate cooking. Previous research demonstrated that nonfat dry milk (NFDM) has the ability to reduce pink color. The objective of this research was to determine if other dairy proteins also possess this capability. In particular, sodium caseinate (SC) and whey protein concentrate (WPC) were evaluated and compared to nonfat dry milk and to no dairy protein containing processed turkey. Pink color development was induced in the poultry products to simulate this defect in products by the addition of nicotinamide to produce nicotinamide hemochrome or sodium nitrite or sodium nitrate to produce nitrosylhemochrome. Prior to protein testing, measurement of these two pigment using reflectance spectrophotometric methods was evaluated. The reflectance ratio of %R at 537 nm divided by %R at 553 nm was able to predict (R²=0.99) concentrations of nicotinamide up to 2%, the highest level tested. The ratio of %R at 650 nm divided by %R at 570 nm was able to predict nitrite (R²=0.97) below 20 ppm. To narrow the possible dairy protein choices, three WPC and two SC dairy proteins, along with nonfat dry milk were evaluated for their ability to inhibit nicotinamide and nitrite induced pink color. Results of this prescreening indicated that variations among the different types of proteins existed in both their abilities to reduce the pink color when pink color generating ligands were intentionally added, and when no ligands were added. Some of the dairy proteins actually increased the redness of the control turkey formulation. The WPC (Alacen 882, New Zealand Milk Products, North America, Inc, Santa Rosa, CA) and SC (Alanate 180 New Zealand Milk Products, North America, Inc., Santa Rosa, CA) protein products chosen in the prescreening were evaluated with nonfat dry milk at various levels. A simplex lattice response surface design enabled prediction of these proteins' effects on red color at combinations of up to and including 3.0% added dairy protein. Sodium nitrate did not appear to increase redness of control samples and therefore was not discussed in detail. The WPC and NFDM proteins tested were able to reduce CIE a* values at both 1.5 and 3% and in combination with each other at 1.5% of each protein (P<0.05) regardless of ligand treatment. Of these treatments, SC had the least effect on CIE a*. With the exception of SC, the dairy proteins increased product yield (P<0.05) in all treatment combinations. Using the response surface prediction ability, other combinations of dairy proteins, not specifically tested in this research, were shown to optimize pink color reduction. / Master of Science