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435 results on '"Ho, Ann"'

51. REMOVED: Use of hydrogen peroxide as an effective disinfectant to Actinobacillus ureae

Author

Chan Wha Kim, Ho Hyuk Jang, Sung Ho Ann, and Myung Deok Kim

Subjects
chemistry.chemical_compound, chemistry, Disinfectant, Actinobacillus ureae, Bioengineering, Biology, Hydrogen peroxide, GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries), Applied Microbiology and Biotechnology, Biochemistry, Microbiology
Abstract

This article has been removed at the request of the Editor-in-Chief and author. Please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy ). Reason: This article has been removed due to concerns in the release of proprietary information.

Published
2008

52. Determination of pKa Values of Carboxyl Groups in the N-Terminal Domain of Rat CD2: Anomalous pKa of a Glutamate on the Ligand-Binding Surface

Author

Mark S. B. McAlister, Paul C. Driscoll, Ho Ann Chen, and Mark Pfuhl

Subjects
Models, Molecular, Magnetic Resonance Spectroscopy, Low protein, Stereochemistry, T-Lymphocytes, Static Electricity, CD2 Antigens, Glutamic Acid, CD48 Antigen, Biochemistry, Acid dissociation constant, Antigens, CD, Cell Adhesion, Side chain, Animals, Carbon Isotopes, Nitrogen Isotopes, Chemistry, Titrimetry, Glutamic acid, Nuclear magnetic resonance spectroscopy, Hydrogen-Ion Concentration, Ligand (biochemistry), Rats, Mutation, Proton NMR, Titration, Hydrogen, Protein Binding
Abstract

The ligand-binding surface of the T-lymphocyte glycoprotein CD2 has an unusually high proportion of charged residues, and ionic interactions are thought to play a significant role in defining the ligand specificity and binding affinity of CD2 with the structurally homologous ligands CD48 (in rodents) and CD58 (in humans). The determination of the electrostatic properties of these proteins can therefore contribute to our understanding of structure-activity relationships for these adhesion complexes that underpin T-cell adhesion to antigen-presenting cells. In this study, we investigated the pH titration behavior of the carboxyl groups of the N-terminal domain of rat CD2 (CD2d1) using the chemical shifts of backbone amide nitrogen-15 ((15)N) and proton NMR resonances, and carboxyl carbon-13 ((13)C) signals. The analysis revealed the presence of a glutamate (Glu41) on the binding surface of rat CD2 with an unusually elevated acidity constant (pK(a) = 6.73) for CD2d1 samples at 1.2 mM concentration. pH titration of CD2d1 at low protein concentration (0.1 mM) resulted in a slight decrease of the measured pK(a) of Glu41 to 6.36. The ionization of Glu41 exhibited reciprocal interactions with a second glutamate (Glu29) in a neighboring location, with both residues demonstrating characteristic biphasic titration behavior of the carboxyl (13)C resonances. Measurements at pH 5.5 of the two-bond deuterium isotope shift for the (13)C carboxyl resonances for Glu41 and Glu29 [(2)DeltaC(delta)(O(epsilon)D) = 0.2 and 0.1 ppm, respectively] were consistent with the assignment of the anomalous pK(a) to Glu41, under the strong influence of Glu29. The characterization of single site mutations of CD2d1 residues Glu41 and Glu29 to glutamine confirmed the anomalous pK(a) for Glu41, and indicated that electrostatic interaction with the Glu29 side chain is a significant contributing influence for this behavior in the wild-type protein. The implications of these observations are discussed with respect to recent structural and functional analyses of the interaction of rat CD2 with CD48. In particular, CD2 Glu41 must be a candidate residue to explain the previously reported strong pH dependence of binding of these two proteins in vitro.

Published
2000

56. Supplementary material. Voluntary alcohol drinking enhances proopiomelanocortin gene expression in nucleus accumbens shell and hypothalamus of sardinian alcohol-preferring rats

Author

Zhou, Yan, Colombo, Giancarlo, Niikura, Keiichi, Carai, Mauro A. M., Femenía, Teresa, García-Gutiérrez, María Salud, Manzanares, Jorge, Ho, Ann, Gessa, Gian Luigi, Kreek, Mary Jeanne, Zhou, Yan, Colombo, Giancarlo, Niikura, Keiichi, Carai, Mauro A. M., Femenía, Teresa, García-Gutiérrez, María Salud, Manzanares, Jorge, Ho, Ann, Gessa, Gian Luigi, and Kreek, Mary Jeanne

Abstract

Data S1. Genetically determined differences between sP and sNP rats in voluntary alcohol drinking, and the effects on orexin and ppDyn in RNA levels in the lateral hypothalamus, and plasma prolactin levels, with methods.

Published
2013

60. Voluntary Alcohol Drinking Enhances Proopiomelanocortin Gene Expression in Nucleus Accumbens Shell and Hypothalamus of Sardinian Alcohol-Preferring Rats

Author

Zhou, Yan, primary, Colombo, Giancarlo, additional, Niikura, Keiichi, additional, Carai, Mauro A. M., additional, Femenía, Teresa, additional, García-Gutiérrez, Maria S., additional, Manzanares, Jorge, additional, Ho, Ann, additional, Gessa, Gian Luigi, additional, and Kreek, Mary Jeanne, additional

Published
2012
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61. Effects of Hepatitis C and HIV on Cognition in Women

Author

Crystal, Howard, primary, Kleyman, Inna, additional, Anastos, Kathryn, additional, Lazar, Jason, additional, Cohen, Mardge, additional, Liu, Chenglong, additional, Pearce, Leigh, additional, Golub, Elizabeth, additional, Valcour, Victor, additional, Ho, Ann, additional, Strickler, Howard, additional, Peters, Marion, additional, Kovacs, Andrea, additional, Holman, Susan, additional, Kreek, Mary Jeanne, additional, and Manly, Jennifer, additional

Published
2012
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67. “Binge” cocaine differentially alters preproenkephalin mRNA levels in guinea pig brain

Author

LaForge, K. Steven, Yuferov, Vadim, Zhou, Yan, Ho, Ann, Nyberg, Fred, Kreek, Mary Jeanne, LaForge, K. Steven, Yuferov, Vadim, Zhou, Yan, Ho, Ann, Nyberg, Fred, and Kreek, Mary Jeanne

Abstract

Male Hartley guinea pigs were administered i.p. injections of cocaine or saline for 2 or 7 days in a "binge" paradigm. RNA was isolated from dissected brain regions and levels of preproenkephalin mRNA and total RNA were quantified by RNase protection assays. Following 2 days of "binge" cocaine administration, no significant alterations in preproenkephalin mRNA levels were detected in six brain regions. Following 7 days of cocaine administration, however, lower levels of preproenkephalin mRNA were observed in the nucleus accumbens and hypothalamus of cocaine-treated animals and higher levels in the frontal cortex and amygdala. These findings differed from previous studies in the rat, so an additional experiment was performed with animals treated at the 7 day time point. For increased statistical power, data from the two experiments were combined and examined by two-way ANOVAs; in this combined analysis, increases in preproenkephalin mRNA were observed in frontal cortex, amygdala, and hippocampus, decreases were found in the nucleus accumbens and hypothalamus, with no change in thalamus, caudate putamen, or cerebellum. These observed differences between guinea pigs and rats make this species an interesting model for neurobiological studies of cocaine-induced alterations in neuropeptide gene expression in the mammalian brain.

Published
2003
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68. A C17T polymorphism in the mu opiate receptor is associated with quantitative measures of drug use in African American women

Author

Crystal, Howard A., primary, Hamon, Sara, additional, Randesi, Matthew, additional, Cook, Judith, additional, Anastos, Kathryn, additional, Lazar, Jason, additional, Liu, Chenglong, additional, Pearce, Leigh, additional, Golub, Elizabeth, additional, Valcour, Victor, additional, Weber, Kathleen M., additional, Holman, Susan, additional, Ho, Ann, additional, and Kreek, Mary Jeanne, additional

Published
2010
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80. Mouse Model of the OPRM1 (A118G) Polymorphism: Differential Heroin Self-Administration Behavior Compared with Wild-Type Mice.

Author

Zhang, Yong, Picetti, Roberto, Butelman, Eduardo R, Ho, Ann, Blendy, Julie A, and Kreek, Mary Jeanne

Subjects
OPIOID receptors, HEROIN, SINGLE nucleotide polymorphisms, DOPAMINE, LABORATORY mice, NEUROPSYCHOPHARMACOLOGY
Abstract

Mu-opioid receptors (MOPRs) are the target of heroin and other prescription opioids, which are currently responsible for massive addiction morbidity in the US. The gene coding for the human MOPR (OPRM1) has an important functional single nucleotide polymorphism (SNP), A118G. The OPRM1 A118G genotype results in substantially increased risk of heroin addiction in humans; however, the neurobiological mechanism for this increased risk is not fully understood. This study examined heroin self-administration (SA) behavior in A112G (G/G) mice, harboring a functionally equivalent SNP in Oprm1 with a similar amino acid substitution, in extended (4 h) SA sessions. Adult male and female G/G mice and 'wild-type' litter mates (A/A) were allowed to self-administer heroin (0.25 mg/kg/unit dose, FR1 with a nose poke response) for 4 h/day, for 10 consecutive days. Half of the mice then continued in a heroin dose-response study, while extinction from heroin SA was studied in the other half. In vivo microdialysis was used to measure acute heroin-induced increases of striatal dopamine in the GG vs AA genotypes. Male and female G/G mice responded for heroin significantly more (and thus had greater intake) than A/A mice, in the initial 10 days of heroin SA, and in the subsequent dose-response study. There were no significant differences in extinction of SA between the A/A and G/G mice. Heroin-induced increases in striatal dopamine levels are higher in the GG mice than in the AA mice. Both male and female G/G mice self-administered more heroin than did A/A mice over a 10-day period, possibly because of the greater increases of heroin-induced striatal dopamine in the GG mice. Furthermore, G/G male mice escalated the amount of heroin self-administration across 10 extended-access sessions more than A/A male mice did. These are the first studies to examine the acquisition of heroin SA in this mouse model. These studies may lead to a better understanding of the neurobiological and behavioral mechanisms that underlie greater risk of heroin addiction in carriers of the A118G SNP. [ABSTRACT FROM AUTHOR]

Published
2015
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