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Author (up) Dingley, A.J.; Lorenzen, I.; Grotzinger, J. file  url
openurl 
  Title NMR analysis of viral protein structures Type Journal Article
  Year 2008 Publication Methods in Molecular Biology (Clifton, N.J.) Abbreviated Journal Methods Mol Biol  
  Volume 451 Issue Pages 441-462  
  Keywords Cloning, Molecular; DNA, Complementary; Indicators and Reagents; Magnetic Resonance Spectroscopy--methods; Models, Molecular; Protein Conformation; Recombinant Proteins--chemistry; Solutions; Viral Proteins--chemistry, genetics, isolation & purification  
  Abstract Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool to study the three-dimensional structure of proteins and nucleic acids at atomic resolution. Since the NMR data can be recorded in solution, conditions such as pH, salt concentration, and temperature can be adjusted so as to closely mimic the biomacromolecules natural milieu. In addition to structure determination, NMR applications can investigate time-dependent phenomena, such as dynamic features of the biomacromolecules, reaction kinetics, molecular recognition, or protein folding. The advent of higher magnetic field strengths, new technical developments, and the use of either uniform or selective isotopic labeling techniques, currently allows NMR users the opportunity to investigate the tertiary structure of biomacromolecules of approximately 50 kDa. This chapter will outline the basic protocol for structure determination of proteins by NMR spectroscopy. In general, there are four main stages: (i) preparation of a homogeneous protein sample, (ii) the recording of the NMR data sets, (iii) assignment of the spectra to each NMR observable atom in the protein, and (iv) generation of structures using computer software and the correctly assigned NMR data.  
  Call Number Serial 782  
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Author (up) Gajer, P.; Brotman, R.M.; Bai, G.; Sakamoto, J.; Schutte, U.M.E.; Zhong, X.; Koenig, S.S.K.; Fu, L.; Ma, Z.S.; Zhou, X.; Abdo, Z.; Forney, L.J.; Ravel, J. file  url
openurl 
  Title Temporal dynamics of the human vaginal microbiota Type Journal Article
  Year 2012 Publication Science Translational Medicine Abbreviated Journal Sci Transl Med  
  Volume 4 Issue 132 Pages 132ra52  
  Keywords Bacteria/classification/genetics; Female; Humans; Magnetic Resonance Spectroscopy; Metabolome; Metabolomics; Metagenome/genetics/*physiology; Models, Biological; Phylogeny; Time Factors; Vagina/*microbiology; Microbiome  
  Abstract Elucidating the factors that impinge on the stability of bacterial communities in the vagina may help in predicting the risk of diseases that affect women's health. Here, we describe the temporal dynamics of the composition of vaginal bacterial communities in 32 reproductive-age women over a 16-week period. The analysis revealed the dynamics of five major classes of bacterial communities and showed that some communities change markedly over short time periods, whereas others are relatively stable. Modeling community stability using new quantitative measures indicates that deviation from stability correlates with time in the menstrual cycle, bacterial community composition, and sexual activity. The women studied are healthy; thus, it appears that neither variation in community composition per se nor higher levels of observed diversity (co-dominance) are necessarily indicative of dysbiosis.  
  Call Number Serial 2175  
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Author (up) Garwood, M.; DelaBarre, L. file  url
doi  openurl
  Title The return of the frequency sweep: designing adiabatic pulses for contemporary NMR Type Journal Article
  Year 2001 Publication Journal of Magnetic Resonance (San Diego, Calif. : 1997) Abbreviated Journal J Magn Reson  
  Volume 153 Issue 2 Pages 155-177  
  Keywords Brain/anatomy & histology; Brain Mapping; Humans; Magnetic Resonance Spectroscopy/*methods; Rotation  
  Abstract Frequency-modulated (FM) pulses that function according to adiabatic principles are becoming increasingly popular in many areas of NMR. Often adiabatic pulses can extend experimental capabilities and minimize annoying experimental imperfections. Here, adiabatic principles and some of the current methods used to create these pulses are considered. The classical adiabatic rapid passage, which is a fundamental element upon which all adiabatic pulses and sequences are based, is analyzed using vector models in different rotating frames of reference. Two methods to optimize adiabaticity are described, and ways to tailor modulation functions to best satisfy specific experimental needs are demonstrated. Finally, adiabatic plane rotation pulses and frequency-selective multiple spin-echo sequences are considered.  
  Call Number Serial 438  
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Author (up) Hall, A.C.; Suarez, C.; Hom-Choudhury, A.; Manu, A.N.; Hall, C.D.; Kirkovits, G.J.; Ghiriviga, I. file  url
openurl 
  Title Cation transport by a redox-active synthetic ion channel Type Journal Article
  Year 2003 Publication Organic & Biomolecular Chemistry Abbreviated Journal Org Biomol Chem  
  Volume 1 Issue 16 Pages 2973-2982  
  Keywords Cations; Electrochemistry/methods; Ferrous Compounds/*chemistry; Ion Channels/chemical synthesis/*chemistry; Ion Transport; Kinetics; Lipid Bilayers/*chemistry; Magnetic Resonance Spectroscopy/methods; Oxidation-Reduction; Phosphatidylethanolamines/chemistry; Sodium/chemistry/metabolism; Spectrometry, Fluorescence  
  Abstract The synthesis, cation binding and transmembrane conductive properties of a novel group of synthetic ion channels containing a redox-active centre are described. Experiments using a black lipid membrane preparation revealed that these compounds function effectively as ion channels. Subsequent 23Na NMR spectroscopy studies focused on a synthesized ion channel with a ferrocene centre. When incorporated in vesicular bilayers, this channel was demonstrated to support a Na+ flux that was at least six times faster than ion transport by monensin. Since oxidation of the ferrocene moiety completely inhibited the Na+ transport, the redox-active centre provides a potential mechanism for controlling ion flux.  
  Call Number Serial 512  
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Author (up) Mollet, K.; Catak, S.; Waroquier, M.; Van Speybroeck, V.; D'hooghe, M.; De Kimpe, N. file  url
doi  openurl
  Title Stereoselective synthesis of cis-3,4-disubstituted piperidines through ring transformation of 2-(2-mesyloxyethyl)azetidines Type Journal Article
  Year 2011 Publication The Journal of Organic Chemistry Abbreviated Journal J Org Chem  
  Volume 76 Issue 20 Pages 8364-8375  
  Keywords Aza Compounds; Azetidines/*chemistry; Chemistry, Pharmaceutical/*methods; Halogenation; Hydrolysis; Magnetic Resonance Spectroscopy; Mesylates/*chemistry; Models, Chemical; Molecular Structure; Piperidines/*chemical synthesis; Stereoisomerism; beta-Lactams/*chemistry  
  Abstract The reactivity of 2-(2-mesyloxyethyl)azetidines, obtained through monochloroalane reduction and mesylation of the corresponding beta-lactams, with regard to different nucleophiles was evaluated for the first time, resulting in the stereoselective preparation of a variety of new 4-acetoxy-, 4-hydroxy-, 4-bromo-, and 4-formyloxypiperidines. During these reactions, transient 1-azoniabicyclo[2.2.0]hexanes were prone to undergo an S(N)2-type ring opening to afford the final azaheterocycles, which was rationalized by means of a detailed computational analysis. This approach constitutes a convenient alternative for the known preparation of 3,4-disubstituted 5,5-dimethylpiperidines, providing an easy access to the 5,5-nor-dimethyl analogues as valuable templates in medicinal chemistry. Furthermore, cis-4-bromo-3-(phenoxy or benzyloxy)piperidines were elaborated into the piperidin-3-one framework via dehydrobromination followed by acid hydrolysis.  
  Call Number Serial 231  
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Author (up) Privalov, P.L.; Griko YuV; Venyaminov SYu; Kutyshenko, V.P. file  url
openurl 
  Title Cold denaturation of myoglobin Type Journal Article
  Year 1986 Publication Journal of Molecular Biology Abbreviated Journal J Mol Biol  
  Volume 190 Issue 3 Pages 487-498  
  Keywords Animals; Calorimetry; *Cetacea; *Cold Temperature; *Hemeproteins; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; *Metmyoglobin; Protein Denaturation; Spectrum Analysis; Temperature; Thermodynamics; *Whales  
  Abstract The stability of the structure of sperm whale metmyoglobin has been studied in various solutions, in the temperature range -8 degrees C to 100 degrees C, by scanning microcalorimetry, light absorption, circular dichroism, nuclear magnetic resonance spectroscopy and viscosimetry. It has been shown that in 10 mM-sodium acetate solutions (pH 3.5 to 3.9) the protein molecule undergoes a reversible conformational transition into a non-compact disordered state not only when the solution is heated above room temperature but also when it is cooled. In this state the protein does not have a tertiary structure, although it retains some residual ellipticity, which may be caused by the fluctuating alpha-helical conformation of the unfolded polypeptide chain. The disruption of the native protein structure both on cooling (cold-denaturation) and on heating (heat-denaturation) proceeds in an “all-or-none” manner, with a significant and similar increase of the protein heat capacity, but with inverse enthalpic and entropic effects: the enthalpy and entropy of the protein molecule decrease during cold-denaturation and increase during heat-denaturation.  
  Call Number Serial 1564  
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Author (up) Rupsingh, R.; Borrie, M.; Smith, M.; Wells, J.L.; Bartha, R. file  url
doi  openurl
  Title Reduced hippocampal glutamate in Alzheimer disease Type Journal Article
  Year 2011 Publication Neurobiology of Aging Abbreviated Journal Neurobiol Aging  
  Volume 32 Issue 5 Pages 802-810  
  Keywords Aged; Aged, 80 and over; Alzheimer Disease/diagnosis/*metabolism; Biological Markers/analysis; Choline/metabolism; Creatine/metabolism; Female; Glutamic Acid/analysis/*deficiency; Hippocampus/chemistry/*metabolism; Humans; Inositol/metabolism; Magnetic Resonance Spectroscopy/methods; Male  
  Abstract Altered neurometabolic profiles have been detected in Alzheimer disease (AD) using (1)H magnetic resonance spectroscopy (MRS), but no definitive biomarker of mild cognitive impairment (MCI) or AD has been established. This study used MRS to compare hippocampal metabolite levels between normal elderly controls (NEC) and subjects with MCI and AD. Short echo-time (TE=46 ms) (1)H spectra were acquired at 4T from the right hippocampus of 23 subjects with AD, 12 subjects with MCI and 15 NEC. Absolute metabolite levels and metabolite ratios were compared between groups using a multivariate analysis of covariance (covariates: age, sex) followed by post hoc Tukey's test (p<0.05 significant). Subjects with AD had decreased glutamate (Glu) as well as decreased Glu/creatine (Cr), Glu/myo-inositol (mI), Glu/N-acetylaspartate (NAA), and NAA/Cr ratios compared to NEC. Subjects with AD also had decreased Glu/mI ratio compared to MCI. There were no differences between subjects with MCI and NEC. Therefore, in addition to NAA/Cr, decreased hippocampal Glu may be an indicator of AD.  
  Call Number Serial 138  
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Author (up) Seedat, S.; Videen, J.S.; Kennedy, C.M.; Stein, M.B. file  url
doi  openurl
  Title Single voxel proton magnetic resonance spectroscopy in women with and without intimate partner violence-related posttraumatic stress disorder Type Journal Article
  Year 2005 Publication Psychiatry Research Abbreviated Journal Psychiatry Res  
  Volume 139 Issue 3 Pages 249-258  
  Keywords Adult; Aspartic Acid/analogs & derivatives/metabolism; Brain/metabolism; Choline/metabolism; Conflict (Psychology); Creatine/metabolism; Diagnostic and Statistical Manual of Mental Disorders; Female; Humans; *Magnetic Resonance Spectroscopy; Severity of Illness Index; *Sexual Partners; Spouse Abuse/*psychology; Stress Disorders, Post-Traumatic/diagnosis/*etiology/metabolism  
  Abstract Preliminary in vivo proton magnetic spectroscopic ((1)H-MRS) studies of N-acetylaspartate (a putative marker of neuronal viability and function) in combat veterans and maltreated children with posttraumatic stress disorder (PTSD) suggest altered neuronal integrity in anterior cingulate and medial temporal lobe structures. In this study, (1)H-MRS was used to measure N-acetylaspartate (NAA), choline (Cho) and myo-inositol (mI) relative to creatine (Cr) in the anterior cingulate of 16 women with histories of intimate partner violence (7 with a DSM-IV diagnosis of PTSD, 9 without PTSD) and 11 healthy, non-abused comparison subjects. The relationship between anterior cingulate chemistry and performance on the Stroop Color-Word task and Part B of the Trail Making Test was also examined. There were no significant differences in anterior cingulate or occipital gray matter metabolite ratios of NAA/Cr and Cho/Cr between intimate partner violence and healthy comparison subjects. Intimate partner violence subjects with PTSD had significantly higher anterior cingulate Cho/Cr than intimate partner violence subjects without PTSD. There was evidence that the subjects with PTSD suffered more severe intimate partner violence as measured by the Conflict Tactics Scale-Revised. Metabolite ratios were not significantly correlated with performance on the Stroop or Trails B. Our findings, in agreement with earlier studies, showed significant alterations in anterior cingulate chemistry in women with PTSD. In contrast to other studies, we found an increase in Cho/Cr rather than a decrease in NAA/Cr, indicating alterations in glia, instead of neuronal dropout.  
  Call Number Serial 83  
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Author (up) Thaker, B.T.; Barvalia, R.S. file  url
doi  openurl
  Title Microwave assisted synthesis and characterization of unsymmetrical tetradentate Schiff base complexes of VO(IV) and MoO(V) Type Journal Article
  Year 2011 Publication Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy Abbreviated Journal Spectrochim Acta A Mol Biomol Spectrosc  
  Volume 84 Issue 1 Pages 51-61  
  Keywords Electron Spin Resonance Spectroscopy; Electrons; Ligands; Magnetic Phenomena; Magnetic Resonance Spectroscopy; Mass Spectrometry; *Microwaves; Molybdenum/*chemistry; Oxides/*chemistry; Physical Phenomena; Powders; Schiff Bases/*chemical synthesis/*chemistry; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared; Stereoisomerism; Temperature; Thermogravimetry; Vanadates/*chemistry  
  Abstract Microwave synthesis, is green chemical method, simple, sensitive, reducing solvent amount and reaction time. The attempt was made to synthesize the unsymmetrical tetradentate N(2)O(2) ligands and their VO(IV) and MoO(V) unsymmetrical tetradentate Schiff base complexes by classical and microwave techniques using domestic microwave oven. The resulting unsymmetrical Schiff base ligands L(1)-L(3) characterized by different spectral methods. Their complexes with oxocations of VO(IV) and MoO(V) have been synthesized and characterized by elemental analyses, conductometric measurements, infrared and electronic absorption, (1)H NMR spectra, mass spectrometry, ESR spectra, magnetic susceptibility measurement and thermal study. The study suggests that the oxo metal ion is bonded to the ligand through the oxygen and imino nitrogen and the geometry around metal ion is distorted octahedral.  
  Call Number Serial 426  
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Author (up) Tsikolia, M.; Hall, A.C.; Suarez, C.; Nylander, Z.O.; Wardlaw, S.M.; Gibson, M.E.; Valentine, K.L.; Onyewadume, L.N.; Ahove, D.A.; Woodbury, M.; Mongare, M.M.; Hall, C.D.; Wang, Z.; Draghici, B.; Katritzky, A.R. file  url
doi  openurl
  Title Synthesis and characterization of a redox-active ion channel supporting cation flux in lipid bilayers Type Journal Article
  Year 2009 Publication Organic & Biomolecular Chemistry Abbreviated Journal Org Biomol Chem  
  Volume 7 Issue 18 Pages 3862-3870  
  Keywords Biological Transport; Cations/*metabolism; Cell Membrane/chemistry/metabolism; Electric Conductivity; Ferrous Compounds/chemistry; Ion Channels/*chemical synthesis/chemistry/*metabolism; Lipid Bilayers/chemistry/*metabolism; Magnetic Resonance Spectroscopy; Oxidation-Reduction; Spectrometry, Fluorescence  
  Abstract The synthesis, cation binding and transmembrane conductive properties of a novel synthetic ion channel containing a redox-active ferrocene unit are described. Fluorescence spectroscopy was used to demonstrate that the channel supports multiple ion coordination and association constants for 1:1 and 1:2 (channel:cation) coordination for both Na(+) and K(+) were evaluated. Experiments using a black lipid membrane preparation revealed that this compound functioned effectively as an ion channel for both Na(+) and K(+). Concomitant (23)Na NMR spectroscopy studies supported this finding and revealed a Na(+) flux, at least 5 times higher than ion transport rates by monensin. Furthermore, oxidation of the redox-active centre (Fe(2+) to Fe(3+)) effectively inhibited ion transport.  
  Call Number Serial 511  
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