2,433 research outputs found
I cementi vetroionomerici : nuove prospettive nella pratica clinica
No full textI cementi vetroionomerici (CVI) sono materiali di introduzione piuttosto recente in odontoiatria, essendo comparsi sul mercato a metà degli anni Settanta. Fin dalle prime formulazioni mostravano vantaggi considerevoli: la creazione di un legame chimico sia con lo smalto che con il collagene dentinale
Biochemical Characterization Of Uracil Phosphoribosyltransferase From Mycobacterium Tuberculosis
No full textUracil phosphoribosyltransferase (UPRT) catalyzes the conversion of uracil and 5-phosphoribosyl-α-1-pyrophosphate (PRPP) to uridine 5′-monophosphate (UMP) and pyrophosphate (PPi). UPRT plays an important role in the pyrimidine salvage pathway since UMP is a common precursor of all pyrimidine nucleotides. Here we describe cloning, expression and purification to homogeneity of upp-encoded UPRT from Mycobacterium tuberculosis (MtUPRT). Mass spectrometry and N-terminal amino acid sequencing unambiguously identified the homogeneous protein as MtUPRT. Analytical ultracentrifugation showed that native MtUPRT follows a monomer-tetramer association model. MtUPRT is specific for uracil. GTP is not a modulator of MtUPRT ativity. MtUPRT was not significantly activated or inhibited by ATP, UTP, and CTP. Initial velocity and isothermal titration calorimetry studies suggest that catalysis follows a sequential ordered mechanism, in which PRPP binding is followed by uracil, and PPi product is released first followed by UMP. The pH-rate profiles indicated that groups with pK values of 5.7 and 8.1 are important for catalysis, and a group with a pK value of 9.5 is involved in PRPP binding. 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pp. 97-105Cole, S.T., Brosch, R., Parkhill, J., Garnier, T., Churcher, C., Deciphering the biology of Mycobacterium tuberculosis from the complete genome sequence (1998) Nature, 393, pp. 537-544Villela, A.D., Sánchez-Quitian, Z.A., Ducati, R.G., Santos, D.S., Basso, L.A., Pyrimidine salvage pathway in Mycobacterium tuberculosis (2011) Curr Med Chem, 18, pp. 1286-1298Ducati, R.G., Breda, A., Basso, L.A., Santos, D.S., Purine Salvage Pathway in Mycobacterium tuberculosis (2011) Curr Med Chem, 18, pp. 1258-1275Ducati, R.G., Souto, A.A., Caceres, R.A., de Azevedo Jr, W.F., Basso, L.A., Purine Nucleoside Phosphorylase as a Molecular Target to Develop Active Compounds Against Mycobacterium tuberculosis (2010) Int Rev Biophys Chem, 1, pp. 34-40Ducati, R.G., Basso, L.A., Santos, D.S., de Azevedo Jr., W.F., Crystallographic and docking studies of purine nucleoside phosphorylase from Mycobacterium tuberculosis (2010) Bioorg Med Chem, 18, pp. 4769-4774Ducati, R.G., Santos, D.S., Basso, L.A., Substrate specificity and kinetic mechanism of purine nucleoside phosphorylase from Mycobacterium tuberculosis (2009) Arch Biochem Biophys, 486, pp. 155-164Ducati, R.G., Basso, L.A., Santos, D.S., Mycobacterial shikimate pathway enzymes as targets for drug design (2007) Curr Drug Targets, 8, pp. 423-435Kim, S., Park, D.H., Kim, T.H., Hwang, M., Shim, J., Functional analysis of pyrimidine biosynthesis enzymes using the anticancer drug 5-fluorouracil in Caenorhabditis elegans (2009) FEBS J, 276, pp. 4715-4726Moffatt, B.A., Ashihara, H., Purine and pyrimidine nucleotide synthesis and metabolism (2002) Arabidopsis Book, 1, pp. e0018Kadziola, A., Neuhard, J., Larsen, S., Structure of product-bound Bacillus caldolyticus uracil phosphoribosyltransferase confirms ordered sequential substrate binding (2002) Acta Crystallogr D Biol Crystallogr, 58, pp. 936-945Kantardjieff, K.A., Vasquez, C., Castro, P., Warfel, N.M., Rho, B.S., Structure of pyrR (Rv1379) from Mycobacterium tuberculosis: a persistence gene and protein drug target (2005) Acta Crystallogr D Biol Crystallogr, 61, pp. 355-364Li, J., Huang, S., Chen, J., Yang, Z., Fei, X., Identification and characterization of human uracil phosphoribosyltransferase (UPRTase) (2007) J Hum Genet, 52, pp. 415-422Renck, D., Ducati, R.G., Palma, M.S., Santos, D.S., Basso, L.A., The kinetic mechanism of human uridine phosphorylase 1: Towards the development of enzyme inhibitors for cancer chemotherapy (2010) Arch Biochem Biophys, 497, pp. 35-42Suzuki, N.N., Koizumi, K., Fukushima, M., Matsuda, A., Inagaki, F., Structural basis for the specificity, catalysis, and regulation of human uridine-cytidine kinase (2004) Structure, 12, pp. 751-764Yablonski, M.J., Pasek, D.A., Han, B.D., Jones, M.E., Traut, T.W., Intrinsic activity and stability of bifunctional human UMP synthase and its two separate catalytic domains, orotate phosphoribosyltransferase and orotidine-5′-phosphate decarboxylase (1996) J Biol Chem, 271, pp. 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Struct Biol, 169, pp. 413-423Rostirolla, D.C., Breda, A., Rosado, L.A., Palma, M.S., Basso, L.A., UMP kinase from Mycobacterium tuberculosis: Mode of action and allosteric interactions, and their likely role in pyrimidine metabolism regulation (2011) Arch Biochem Biophys, 505, pp. 202-212Nunes, J.E., Ducati, R.G., Breda, A., Rosado, L.A., de Souza, B.M., Molecular, kinetic, thermodynamic, and structural analyses of Mycobacterium tuberculosis hisD-encoded metal-dependent dimeric histidinol dehydrogenase (EC 1.1.1.23) (2011) Arch Biochem Biophys, 512, pp. 143-153Martinelli, L.K., Ducati, R.G., Rosado, L.A., Breda, A., Selbach, B.P., Recombinant Escherichia coli GMP reductase: kinetic, catalytic and chemical mechanisms, and thermodynamics of enzyme-ligand binary complex formation (2011) Mol Biosyst, 7, pp. 1289-1305de Mendonça, J.D., Adachi, O., Rosado, L.A., Ducati, R.G., Santos, D.S., Kinetic mechanism determination and analysis of metal requirement of dehydroquinate synthase from 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Portia in Primetime: Women Lawyers, Television, and L.A. Law
No full textThe following paper was written in March 1989, when L.A. Law was still in its third season and the author was in her last year at Harvard Law School. The analysis is based on events and characters prior to April 1, 1989. An unedited version of the paper is on file at Harvard Law School. The Epilogue included here updates the author\u27s review of L.A. Law through March 15, 1990
Eenige beschouwingen over de toekomst van ons technisch hoger onderwijs
No full textRede, uitgesproken op den Gedenkdag der Technische Hoogeschool, 8 Januari 1923, door den rector-magnificus Prof. L.A. van Royen.Delft University of Technolog
L.A. Tabulae ad Astra
No full textL.A.: Tabulae ad Astra (Los Angeles: Maps to the Stars) is a series of prints integrating portions of street maps of Los Angeles with gestural lines, impromptu marks from testing pen nibs, and cutting lines on boards—all unwittingly produced in the artist’s studio while working on other projects. The combined layers of intersecting and overlapping marks take on a surprising cartographic character that is reinforced by additional ancient map-like elements such as measurement grids, Latin phrases, beastiary, and scale markers. The resultant prints are also physically connected to the Los Angeles landscape, being printed on paper that was first soaked and stained in the waters of the L.A. River. Together Tabulae ad Astra plays on the constant tensions of control vs. freedom, order vs. complexity, safety vs. adventure, and city vs. wilderness.
Cover images: Design by Rebecca McKinney featuring Tab.10 and ephmera, by Dirk Hagner, courtesy of the artist. Artwork images by Dirk Hagner, courtesy of the artist. All other documentation photographs by Jeff Rau and Melanie Kim, from exhibition in the Earl & Virginia Green Art Gallery. L.A. Tabulae ad Astra (exhibition catalog), by Dirk Hagner Editor: Jeff Rau Contributing author: Karin Lanzoni Copyright © 2015 Earl & Virginia Green Art Gallery. Book design by Rebecca McKinney.https://digitalcommons.biola.edu/exhibit-catalogs/1012/thumbnail.jp
Portia in Primetime: Women Lawyers, Television, and L.A. Law
No full textThe following paper was written in March 1989, when L.A. Law was still in its third season and the author was in her last year at Harvard Law School. The analysis is based on events and characters prior to April 1, 1989. An unedited version of the paper is on file at Harvard Law School. The Epilogue included here updates the author's review of L.A. Law through March 15, 1990
A Look Back on the L.A. Riots: Black-Korean Relations
No full textWhat is the future of Black-Korean communities, post-L.A. riots? According to the author, there is an absence of Asian American issues in books devoted to race relations between ethnic minorities in the U.S. This thesis examines the Los Angeles riots, the histories of each group, and data from qualitative interviews. The author gives an objective and honest analysis of black-Korean relations despite racial, economic, and political biases. Methodology includes qualitative interviews of black respondents and Korean-American respondents
Inter institutional workshop on breakwaters
No full text(1) Functional requirements for Breakwaters - Prof. K.d' Angremond (2) Development of fishery harbors in India - Mr. K. Omprakash (3) Non-rubble Breakwaters and optimisation - Prof. K.d' Angremond (4) Wave energy caisson Breakwaters - Dr. S. Neelamani (5) Partially suspended porous wall Breakwaters - Dr. J.S. Mani (6) Case studies on stability of Breakwaters - Prof. V. Sundar (7) Introduction on Ennore coal port project - Mr. L.A. Mayboom (8) Design of Breakwaters for Ennore port - Mr. R. Haggie (9) Construction of Breakwaters for Ennore port - Mr. S. PearsonHydraulic EngineeringCivil Engineering and Geoscience
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