Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
An amino acid that occurs in vertebrate tissues and in urine. In muscle tissue, creatine generally occurs as phosphocreatine. Creatine is excreted as CREATININE in the urine.
An endogenous substance found mainly in skeletal muscle of vertebrates. It has been tried in the treatment of cardiac disorders and has been added to cardioplegic solutions. (Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Englewood, CO, 1996)
A basic constituent of lecithin that is found in many plants and animal organs. It is important as a precursor of acetylcholine, as a methyl donor in various metabolic processes, and in lipid metabolism.
One of the non-essential amino acids commonly occurring in the L-form. It is found in animals and plants, especially in sugar cane and sugar beets. It may be a neurotransmitter.
Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
NMR spectroscopy on small- to medium-size biological macromolecules. This is often used for structural investigation of proteins and nucleic acids, and often involves more than one isotope.
A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
An isomer of glucose that has traditionally been considered to be a B vitamin although it has an uncertain status as a vitamin and a deficiency syndrome has not been identified in man. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1379) Inositol phospholipids are important in signal transduction.
Stable phosphorus atoms that have the same atomic number as the element phosphorus, but differ in atomic weight. P-31 is a stable phosphorus isotope.
Non-invasive method of vascular imaging and determination of internal anatomy without injection of contrast media or radiation exposure. The technique is used especially in CEREBRAL ANGIOGRAPHY as well as for studies of other vascular structures.
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
The chemical reactions involved in the production and utilization of various forms of energy in cells.
A nonmetallic, diatomic gas that is a trace element and member of the halogen family. It is used in dentistry as flouride (FLUORIDES) to prevent dental caries.
Inorganic salts of phosphoric acid.
A type of imaging technique used primarily in the field of cardiology. By coordinating the fast gradient-echo MRI sequence with retrospective ECG-gating, numerous short time frames evenly spaced in the cardiac cycle are produced. These images are laced together in a cinematic display so that wall motion of the ventricles, valve motion, and blood flow patterns in the heart and great vessels can be visualized.
A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.
A normal intermediate in the fermentation (oxidation, metabolism) of sugar. The concentrated form is used internally to prevent gastrointestinal fermentation. (From Stedman, 26th ed)
A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.
A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.
A diagnostic technique that incorporates the measurement of molecular diffusion (such as water or metabolites) for tissue assessment by MRI. The degree of molecular movement can be measured by changes of apparent diffusion coefficient (ADC) with time, as reflected by tissue microstructure. Diffusion MRI has been used to study BRAIN ISCHEMIA and tumor response to treatment.
The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Calcium and magnesium salts used therapeutically in hepatobiliary dysfunction.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Substances used to allow enhanced visualization of tissues.
The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.
Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.
A biosensing technique in which biomolecules capable of binding to specific analytes or ligands are first immobilized on one side of a metallic film. Light is then focused on the opposite side of the film to excite the surface plasmons, that is, the oscillations of free electrons propagating along the film's surface. The refractive index of light reflecting off this surface is measured. When the immobilized biomolecules are bound by their ligands, an alteration in surface plasmons on the opposite side of the film is created which is directly proportional to the change in bound, or adsorbed, mass. Binding is measured by changes in the refractive index. The technique is used to study biomolecular interactions, such as antigen-antibody binding.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Deuterium. The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.
Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
A component of PHOSPHATIDYLCHOLINES or LECITHINS, in which the two hydroxy groups of GLYCEROL are esterified with fatty acids. (From Stedman, 26th ed) It counteracts the effects of urea on enzymes and other macromolecules.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
The systematic identification and quantitation of all the metabolic products of a cell, tissue, organ, or organism under varying conditions. The METABOLOME of a cell or organism is a dynamic collection of metabolites which represent its net response to current conditions.
The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.
Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)
Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.
The rate dynamics in chemical or physical systems.
Elements of limited time intervals, contributing to particular results or situations.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Pathologic conditions affecting the BRAIN, which is composed of the intracranial components of the CENTRAL NERVOUS SYSTEM. This includes (but is not limited to) the CEREBRAL CORTEX; intracranial white matter; BASAL GANGLIA; THALAMUS; HYPOTHALAMUS; BRAIN STEM; and CEREBELLUM.
One of the convolutions on the medial surface of the CEREBRAL HEMISPHERES. It surrounds the rostral part of the brain and CORPUS CALLOSUM and forms part of the LIMBIC SYSTEM.
Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Posterior portion of the CEREBRAL HEMISPHERES responsible for processing visual sensory information. It is located posterior to the parieto-occipital sulcus and extends to the preoccipital notch.
The study of the composition, chemical structures, and chemical reactions of the NERVOUS SYSTEM or its components.
A complex of gadolinium with a chelating agent, diethylenetriamine penta-acetic acid (DTPA see PENTETIC ACID), that is given to enhance the image in cranial and spinal MRIs. (From Martindale, The Extra Pharmacopoeia, 30th ed, p706)
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
The characteristic three-dimensional shape of a molecule.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
The characteristic 3-dimensional shape of a carbohydrate.
Gadolinium. An element of the rare earth family of metals. It has the atomic symbol Gd, atomic number 64, and atomic weight 157.25. Its oxide is used in the control rods of some nuclear reactors.
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
The dynamic collection of metabolites which represent a cell's or organism's net metabolic response to current conditions.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.
The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.
A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.
The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.
Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.
A mass spectrometric technique that is used for the analysis of a wide range of biomolecules, such as glycoalkaloids, glycoproteins, polysaccharides, and peptides. Positive and negative fast atom bombardment spectra are recorded on a mass spectrometer fitted with an atom gun with xenon as the customary beam. The mass spectra obtained contain molecular weight recognition as well as sequence information.
Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Improvement of the quality of a picture by various techniques, including computer processing, digital filtering, echocardiographic techniques, light and ultrastructural MICROSCOPY, fluorescence spectrometry and microscopy, scintigraphy, and in vitro image processing at the molecular level.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
A metabolic process that converts GLUCOSE into two molecules of PYRUVIC ACID through a series of enzymatic reactions. Energy generated by this process is conserved in two molecules of ATP. Glycolysis is the universal catabolic pathway for glucose, free glucose, or glucose derived from complex CARBOHYDRATES, such as GLYCOGEN and STARCH.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function, known as the Fourier transform, describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine, e.g., analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules, including viruses, and the modified back-projection algorithm universally used in computerized tomography imaging, etc. (From Segen, The Dictionary of Modern Medicine, 1992)
Measurement of the intensity and quality of fluorescence.
Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The isotopic compound of hydrogen of mass 2 (deuterium) with oxygen. (From Grant & Hackh's Chemical Dictionary, 5th ed) It is used to study mechanisms and rates of chemical or nuclear reactions, as well as biological processes.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
An intermediate compound in the metabolism of carbohydrates, proteins, and fats. In thiamine deficiency, its oxidation is retarded and it accumulates in the tissues, especially in nervous structures. (From Stedman, 26th ed)
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Methods for visualizing REGIONAL BLOOD FLOW, metabolic, electrical, or other physiological activities in the CENTRAL NERVOUS SYSTEM using various imaging modalities.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
Benign and malignant central nervous system neoplasms derived from glial cells (i.e., astrocytes, oligodendrocytes, and ependymocytes). Astrocytes may give rise to astrocytomas (ASTROCYTOMA) or glioblastoma multiforme (see GLIOBLASTOMA). Oligodendrocytes give rise to oligodendrogliomas (OLIGODENDROGLIOMA) and ependymocytes may undergo transformation to become EPENDYMOMA; CHOROID PLEXUS NEOPLASMS; or colloid cysts of the third ventricle. (From Escourolle et al., Manual of Basic Neuropathology, 2nd ed, p21)
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
Mitochondria of skeletal and smooth muscle. It does not include myocardial mitochondria for which MITOCHONDRIA, HEART is available.
Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
A conjugated protein which is the oxygen-transporting pigment of muscle. It is made up of one globin polypeptide chain and one heme group.
Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.
A methylpentose whose L- isomer is found naturally in many plant glycosides and some gram-negative bacterial lipopolysaccharides.
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
A type of FLUORESCENCE SPECTROSCOPY using two FLUORESCENT DYES with overlapping emission and absorption spectra, which is used to indicate proximity of labeled molecules. This technique is useful for studying interactions of molecules and PROTEIN FOLDING.
Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.
The rostral part of the frontal lobe, bounded by the inferior precentral fissure in humans, which receives projection fibers from the MEDIODORSAL NUCLEUS OF THE THALAMUS. The prefrontal cortex receives afferent fibers from numerous structures of the DIENCEPHALON; MESENCEPHALON; and LIMBIC SYSTEM as well as cortical afferents of visual, auditory, and somatic origin.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Any visible result of a procedure which is caused by the procedure itself and not by the entity being analyzed. Common examples include histological structures introduced by tissue processing, radiographic images of structures that are not naturally present in living tissue, and products of chemical reactions that occur during analysis.
Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.
Inorganic compounds that contain phosphorus as an integral part of the molecule.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
Acquired or inborn metabolic diseases that produce brain dysfunction or damage. These include primary (i.e., disorders intrinsic to the brain) and secondary (i.e., extracranial) metabolic conditions that adversely affect cerebral function.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
The most common inhibitory neurotransmitter in the central nervous system.
A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.
Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)
The white of an egg, especially a chicken's egg, used in cooking. It contains albumin. (Random House Unabridged Dictionary, 2d ed)
Minimally invasive procedures guided with the aid of magnetic resonance imaging to visualize tissue structures.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
Lower lateral part of the cerebral hemisphere responsible for auditory, olfactory, and semantic processing. It is located inferior to the lateral fissure and anterior to the OCCIPITAL LOBE.
Paired bodies containing mostly GRAY MATTER and forming part of the lateral wall of the THIRD VENTRICLE of the brain.
Tests designed to assess neurological function associated with certain behaviors. They are used in diagnosing brain dysfunction or damage and central nervous system disorders or injury.
An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.
An enzyme that is active in the first step of choline phosphoglyceride (lecithin) biosynthesis by catalyzing the phosphorylation of choline to phosphorylcholine in the presence of ATP. Ethanolamine and its methyl and ethyl derivatives can also act as acceptors. EC 2.7.1.32.
A series of oxidative reactions in the breakdown of acetyl units derived from GLUCOSE; FATTY ACIDS; or AMINO ACIDS by means of tricarboxylic acid intermediates. The end products are CARBON DIOXIDE, water, and energy in the form of phosphate bonds.
Mathematical procedure that transforms a number of possibly correlated variables into a smaller number of uncorrelated variables called principal components.
A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium chelating ability.
Any visual display of structural or functional patterns of organs or tissues for diagnostic evaluation. It includes measuring physiologic and metabolic responses to physical and chemical stimuli, as well as ultramicroscopy.
The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.
Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.
Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.
A principle of estimation in which the estimates of a set of parameters in a statistical model are those quantities minimizing the sum of squared differences between the observed values of a dependent variable and the values predicted by the model.
A compound formed by the combination of hemoglobin and oxygen. It is a complex in which the oxygen is bound directly to the iron without causing a change from the ferrous to the ferric state.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.
Lipid infiltration of the hepatic parenchymal cells resulting in a yellow-colored liver. The abnormal lipid accumulation is usually in the form of TRIGLYCERIDES, either as a single large droplet or multiple small droplets. Fatty liver is caused by an imbalance in the metabolism of FATTY ACIDS.
Non-fatal immersion or submersion in water. The subject is resuscitable.
2-(2,2-Dicyclohexylethyl)piperidine. Coronary vasodilator used especially for angina of effort. It may cause neuropathy and hepatitis.
Relating to the size of solids.
Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.
A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)
Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
A conditionally essential nutrient, important during mammalian development. It is present in milk but is isolated mostly from ox bile and strongly conjugates bile acids.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Non-invasive methods of visualizing the CENTRAL NERVOUS SYSTEM, especially the brain, by various imaging modalities.
A circumscribed collection of purulent exudate in the brain, due to bacterial and other infections. The majority are caused by spread of infected material from a focus of suppuration elsewhere in the body, notably the PARANASAL SINUSES, middle ear (see EAR, MIDDLE); HEART (see also ENDOCARDITIS, BACTERIAL), and LUNG. Penetrating CRANIOCEREBRAL TRAUMA and NEUROSURGICAL PROCEDURES may also be associated with this condition. Clinical manifestations include HEADACHE; SEIZURES; focal neurologic deficits; and alterations of consciousness. (Adams et al., Principles of Neurology, 6th ed, pp712-6)
The circulation of blood through the BLOOD VESSELS of the BRAIN.
A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.
An imaging technique using compounds labelled with short-lived positron-emitting radionuclides (such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18) to measure cell metabolism. It has been useful in study of soft tissues such as CANCER; CARDIOVASCULAR SYSTEM; and brain. SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY is closely related to positron emission tomography, but uses isotopes with longer half-lives and resolution is lower.
Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.
Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.
Large subcortical nuclear masses derived from the telencephalon and located in the basal regions of the cerebral hemispheres.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
Adenosine 5'-(trihydrogen diphosphate). An adenine nucleotide containing two phosphate groups esterified to the sugar moiety at the 5'-position.
Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.
A relatively common neoplasm of the CENTRAL NERVOUS SYSTEM that arises from arachnoidal cells. The majority are well differentiated vascular tumors which grow slowly and have a low potential to be invasive, although malignant subtypes occur. Meningiomas have a predilection to arise from the parasagittal region, cerebral convexity, sphenoidal ridge, olfactory groove, and SPINAL CANAL. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2056-7)
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.
Diminished effectiveness of INSULIN in lowering blood sugar levels: requiring the use of 200 units or more of insulin per day to prevent HYPERGLYCEMIA or KETOSIS.
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.
Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the OCCIPITAL LOBE, and superior to the TEMPORAL LOBES.
Computer-based representation of physical systems and phenomena such as chemical processes.
Non-invasive diagnostic technique for visualizing the PANCREATIC DUCTS and BILE DUCTS without the use of injected CONTRAST MEDIA or x-ray. MRI scans provide excellent sensitivity for duct dilatation, biliary stricture, and intraductal abnormalities.
Analysis of the energy absorbed across a spectrum of x-ray energies/wavelengths to determine the chemical structure and electronic states of the absorbing medium.
The physical characteristics and processes of biological systems.
Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.
A severe emotional disorder of psychotic depth characteristically marked by a retreat from reality with delusion formation, HALLUCINATIONS, emotional disharmony, and regressive behavior.
Electron transfer through the cytochrome system liberating free energy which is transformed into high-energy phosphate bonds.
A major affective disorder marked by severe mood swings (manic or major depressive episodes) and a tendency to remission and recurrence.
Carbon-containing phosphoric acid derivatives. Included under this heading are compounds that have CARBON atoms bound to one or more OXYGEN atoms of the P(=O)(O)3 structure. Note that several specific classes of endogenous phosphorus-containing compounds such as NUCLEOTIDES; PHOSPHOLIPIDS; and PHOSPHOPROTEINS are listed elsewhere.
Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.
An essential amino acid that is required for the production of HISTAMINE.
The science and art of collecting, summarizing, and analyzing data that are subject to random variation. The term is also applied to the data themselves and to the summarization of the data.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
The largest and most lateral of the BASAL GANGLIA lying between the lateral medullary lamina of the GLOBUS PALLIDUS and the EXTERNAL CAPSULE. It is part of the neostriatum and forms part of the LENTIFORM NUCLEUS along with the GLOBUS PALLIDUS.
Treatment process involving the injection of fluid into an organ or tissue.
A physical property showing different values in relation to the direction in or along which the measurement is made. The physical property may be with regard to thermal or electric conductivity or light refraction. In crystallography, it describes crystals whose index of refraction varies with the direction of the incident light. It is also called acolotropy and colotropy. The opposite of anisotropy is isotropy wherein the same values characterize the object when measured along axes in all directions.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
Studies to determine the advantages or disadvantages, practicability, or capability of accomplishing a projected plan, study, or project.
Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)
Maintenance of a constant blood glucose level by perfusion or infusion with glucose or insulin. It is used for the study of metabolic rates (e.g., in glucose, lipid, amino acid metabolism) at constant glucose concentration.
An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating and chronic progressive forms (see MULTIPLE SCLEROSIS, CHRONIC PROGRESSIVE) also occur. (Adams et al., Principles of Neurology, 6th ed, p903)
Proteins found in any species of bacterium.
Fluids composed mainly of water found within the body.

The interaction of rhodium(II) carboxylates with enzymes. (1/24698)

The effect of rhodium(II) acetate, propionate, and methoxyacetate on the activity of 17 enzymes was evaluated. The enzymes were preincubated with the rhodium(II) complexes in order to detect irreversible inhibition. All enzymes that have essential sulfhydryl groups in or near their active site were found to be irreversibly inhibited. Those enzymes without essential sulfhydryl groups were not affected. In each case, the rate of inactivation closely paralleled the observed toxicity and antitumor activity of rhodium(II) carboxylates; that is, rhodium(II) propionate greater than rhodium(II) acetate greater than rhodium(II) methoxyacetate. In addition, those enzymes that have been demonstrated to be most sensitive to established sulfhydryl inhibitors, such as glyceraldehyde-3-phosphate dehydrogenase, were also most sensitive to rhodium(II) carboxylate inactivation. Proton nuclear magnetic resonance measurements made during the titration of rhodium(II) acetate with cysteine showed that breakdown of the carboxylate cage occurred as a result of reaction with this sulfhydryl-containing amino acid.  (+info)

Prodigious substrate specificity of AAC(6')-APH(2"), an aminoglycoside antibiotic resistance determinant in enterococci and staphylococci. (2/24698)

BACKGROUND: High-level gentamicin resistance in enterococci and staphylococci is conferred by AAC(6')-APH(2"), an enzyme with 6'-N-acetyltransferase and 2"-O-phosphotransferase activities. The presence of this enzyme in pathogenic gram-positive bacteria prevents the successful use of gentamicin C and most other aminoglycosides as therapeutic agents. RESULTS: In an effort to understand the mechanism of aminoglycoside modification, we expressed AAC(6')-APH(2") in Bacillus subtilis. The purified enzyme is monomeric with a molecular mass of 57 kDa and displays both the expected aminoglycoside N-acetyltransferase and O-phosphotransferase activities. Structure-function analysis with various aminoglycosides substrates reveals an enzyme with broad specificity in both enzymatic activities, accounting for AAC(6')-APH(2")'s dramatic negative impact on clinical aminoglycoside therapy. Both lividomycin A and paromomycin, aminoglycosides lacking a 6'-amino group, were acetylated by AAC(6')-APH(2"). The infrared spectrum of the product of paromomycin acetylation yielded a signal consistent with O-acetylation. Mass spectral and nuclear magnetic resonance analysis of the products of neomycin phosphorylation indicated that phosphoryl transfer occurred primarily at the 3'-OH of the 6-aminohexose ring A, and that some diphosphorylated material was also present with phosphates at the 3'-OH and the 3"'-OH of ring D, both unprecedented observations for this enzyme. Furthermore, the phosphorylation site of lividomycin A was determined to be the 5"-OH of the pentose ring C. CONCLUSIONS: The bifunctional AAC(6')-APH(2") has the capacity to inactivate virtually all clinically important aminoglycosides through N- and O-acetylation and phosphorylation of hydroxyl groups. The extremely broad substrate specificity of this enzyme will impact on future development of aminoglycosides and presents a significant challenge for antibiotic design.  (+info)

Single atom modification (O-->S) of tRNA confers ribosome binding. (3/24698)

Escherichia coli tRNALysSUU, as well as human tRNALys3SUU, has 2-thiouridine derivatives at wobble position 34 (s2U*34). Unlike the native tRNALysSUU, the full-length, unmodified transcript of human tRNALys3UUU and the unmodified tRNALys3UUU anticodon stem/loop (ASLLys3UUU) did not bind AAA- or AAG-programmed ribosomes. In contrast, the completely unmodified yeast tRNAPhe anticodon stem/loop (ASLPheGAA) had an affinity (Kd = 136+/-49 nM) similar to that of native yeast tRNAPheGmAA (Kd = 103+/-19 nM). We have found that the single, site-specific substitution of s2U34 for U34 to produce the modified ASLLysSUU was sufficient to restore ribosomal binding. The modified ASLLysSUU bound the ribosome with an affinity (Kd = 176+/-62 nM) comparable to that of native tRNALysSUU (Kd = 70+/-7 nM). Furthermore, in binding to the ribosome, the modified ASLLys3SUU produced the same 16S P-site tRNA footprint as did native E. coli tRNALysSUU, yeast tRNAPheGmAA, and the unmodified ASLPheGAA. The unmodified ASLLys3UUU had no footprint at all. Investigations of thermal stability and structure monitored by UV spectroscopy and NMR showed that the dynamic conformation of the loop of modified ASLLys3SUU was different from that of the unmodified ASLLysUUU, whereas the stems were isomorphous. Based on these and other data, we conclude that s2U34 in tRNALysSUU and in other s2U34-containing tRNAs is critical for generating an anticodon conformation that leads to effective codon interaction in all organisms. This is the first example of a single atom substitution (U34-->s2U34) that confers the property of ribosomal binding on an otherwise inactive tRNA.  (+info)

Molecular dynamics studies of U1A-RNA complexes. (4/24698)

The U1A protein binds to a hairpin RNA and an internal-loop RNA with picomolar affinities. To probe the molecular basis of U1A binding, we performed state-of-the-art nanosecond molecular dynamics simulations on both complexes. The good agreement with experimental structures supports the protocols used in the simulations. We compare the dynamics, hydrogen-bonding occupancies, and interfacial flexibility of both complexes and also describe a rigid-body motion in the U1A-internal loop complex that is not observed in the U1A-hairpin simulation. We relate these observations to experimental mutational studies and highlight their significance in U1A binding affinity and specificity.  (+info)

An examination of coaxial stacking of helical stems in a pseudoknot motif: the gene 32 messenger RNA pseudoknot of bacteriophage T2. (5/24698)

The RNA pseudoknot located at the 5' end of the gene 32 messenger RNA of bacteriophage T2 contains two A-form helical stems connected by two loops, in an H-type pseudoknot topology. A combination of multidimensional NMR methods and isotope labeling were used to investigate the pseudoknot structure, resulting in a more detailed structural model than provided by earlier homonuclear NMR studies. Of particular significance, the interface between the stacked helical stems within the pseudoknot motif is described in detail. The two stems are stacked in a coaxial manner, with an approximately 18 degrees rotation of stem1 relative to stem2 about an axis that is parallel to the helical axis. This rotation serves to relieve what would otherwise be a relatively close phosphate-phosphate contact at the junction of the two stems, while preserving the stabilizing effects of base stacking. The ability of the NMR data to determine pseudoknot bending was critically assessed. The data were found to be a modestly precise indicator of pseudoknot bending, with the angle between the helical axes of stem1 and stem2 being in the range of 15+/-15 degrees. Pseudoknot models with bend angles within this range are equally consistent with the data, since they differ by only small amounts in the relatively short-range interproton distances from which the structure was derived. The gene 32 messenger RNA pseudoknot was compared with other RNA structures with coaxial or near-coaxial stacked helical stems.  (+info)

Purinogen is not an endogenous substrate used in endothelial cells during substrate deprivation. (6/24698)

Porcine aortic endothelial cells (PAEC) are known to be metabolically robust. They are capable of surviving extended periods of complete lack of exogenous substrate, and purine release has been shown to be significantly up-regulated. The endogenous substrates used during substrate deprivation, as well as the sources responsible for the increased purine release, have not been completely identified. We tested the possibility that a phosphoglyceroyl-ATP-containing polymer, purinogen, might support PAEC hibernation induced by lack of exogenous substrate. This involved isolation of the acid-insoluble fraction of PAEC, which was presumed to contain purinogen, and analysis by HPLC and 31P NMR. No evidence supporting the presence of triphosphate-containing compounds (purinogen) was found. Similar results were obtained in the rat heart. The majority of the products in the acid-insoluble, alkaline-treated fraction were identified as RNA degradation products (2'- and 3'-nucleoside monophosphates). A [14C]adenosine labelling experiment showed that incorporation of adenosine into the acid-insoluble fraction was almost completely prevented after inhibition of RNA synthesis with actinomycin D. Furthermore, RNA isolated from PAEC and subsequently treated with alkali showed a profile that was almost identical with the HPLC profile of the acid-insoluble fraction. Finally, substrate-free incubation of the cells did not quantitatively or qualitatively influence the distribution of acid-insoluble derivatives. We conclude that PAEC survival during the absence of exogenous substrate is not supported by purinogen but rather by some other, yet-to-be-identified, endogenous substrate.  (+info)

Accumulation of astaxanthin all-E, 9Z and 13Z geometrical isomers and 3 and 3' RS optical isomers in rainbow trout (Oncorhynchus mykiss) is selective. (7/24698)

Concentrations of all-E-, 9Z- and 13Z- geometrical and (3R,3'R), (3R, 3'S) and (3S,3'S) optical isomers of astaxanthin were determined in rainbow trout liver, gut tissues, kidney, skin and blood plasma to evaluate their body distribution. Two cold-pelleted diets containing predominantly all-E-astaxanthin (36.9 mg/kg astaxanthin, 97% all-E-, 0.4% 9Z-, 1.5% 13Z-astaxanthin, and 1.1% other isomers, respectively) or a mixture of all-E- and Z-astaxanthins (35.4 mg/kg astaxanthin, 64% all-E-, 18.7% 9Z-, 12.3% 13Z-astaxanthin, and 2.0% other isomers, respectively), were fed to duplicate groups of trout for 69 d. Individual E/Z isomers were identified by VIS- and 1H-NMR-spectrometry, and quantified by high-performance liquid chromatography. Significantly higher total carotenoid concentration was observed in plasma of trout fed diets with all-E-astaxanthin (P < 0.05). The relative E/Z-isomer concentrations of plasma, skin and kidney were not significantly different among groups, whereas all-E-astaxanthin was higher in intestinal tissues and 13Z-astaxanthin was lower in liver of trout fed all-E-astaxanthin (P < 0.05). The relative amount of hepatic 13Z-astaxanthin (39-49% of total astaxanthin) was higher than in all other samples (P < 0.05). Synthetic, optically inactive astaxanthin was used in all experiments, and the determined dietary ratio between the 3R,3'R:3R, 3'S (meso):3S,3'S optical isomers was 25.3:49.6:25.1. The distribution of R/S-astaxanthin isomers in feces, blood, liver and fillet was similar to that in the diets. The ratio between (3S,3'S)- and (3R,3'R)-astaxanthin in the skin and posterior kidney was ca. 2:1 and 3:1, respectively, regardless of dietary E/Z-astaxanthin composition. The results show that geometrical and optical isomers of astaxanthin are distributed selectively in different tissues of rainbow trout.  (+info)

Biophysical characterization of the structure of the amino-terminal region of gp41 of HIV-1. Implications on viral fusion mechanism. (8/24698)

A peptide of 51 amino acids corresponding to the NH2-terminal region (5-55) of the glycoprotein gp41 of human immunodeficiency virus type 1 was synthesized to study its conformation and assembly. Nuclear magnetic resonance experiments indicated the sequence NH2-terminal to the leucine zipper-like domain of gp41 was induced into helix in the micellar solution, in agreement with circular dichroism data. Light scattering experiment showed that the peptide molecules self-assembled in water into trimeric structure on average. That the peptide molecules oligomerize in aqueous solution was supported by gel filtration and diffusion coefficient experiments. Molecular dynamics simulation based on the NMR data revealed a flexible region adjacent to the hydrophobic NH2 terminus of gp41. The biological significance of the present findings on the conformational flexibility and the propensity of oligomerization of the peptide may be envisioned by a proposed model for the interaction of gp41 with membranes during fusion process.  (+info)

TY - JOUR. T1 - Method of determining protein conformations by the two-dimensional nuclear overhauser enhancement spectroscopy data. AU - Sherman, S. A.. AU - Andrianov, A. M.. AU - Akhrem, A. A.. PY - 1987/4. Y1 - 1987/4. N2 - A method is suggested to determine the most probable values of the angles, y of the protein backbone by the data on the availability and absence of d connectivities in the two-dimensional nuclear Overhauser enhancement spectra. In view of this, the dependences of the protonproton distances in dipeptide units of L-amino acid residues on the dihedral angles tp, y, x, are considered and the conformational states of amino acid residues of the proteins with the known spatial structure are analysed statistically. The potentialities of the method are assessed with the aid of model spectral nuclear magnetic resonance (NMR) parameters obtained from the X-ray data for the bovine pancreatic trypsin inhibitor and avian pancreatic polypeptide. It is shown that the developed procedure ...
TY - JOUR. T1 - Proton nuclear magnetic resonance assignments and secondary structure determination of the Co1E1 rop (rom) protein. AU - Eberle, W.. AU - Klaus, W.. AU - Cesareni, G.. AU - Sander, C.. AU - Rosch, P.. PY - 1990. Y1 - 1990. N2 - The complete resonance assignment of the Co1E1 rop (rom) protein at pH 2.3 was obtained by two-dimensional (2D) proton nuclear magnetic resonance spectroscopy (1H NMR) at 500 and 600 MHz using through-bond and through-space connectivities. Sequential assignments and elements of regular secondary structure were deduced by analysis of nuclear Overhauser enhancement spectroscopy (NOESY) experiments and 3J(HNα) coupling constants. One 7.2-kDa monomer of the homodimer consists of two antiparallel helices connected by a hairpin loop at residue 31. The C-terminal peptide consisting of amino acids 59-63 shows no stable conformation. The dimer forms a four-helix bundle with opposite polarization of neighboring elements in agreement with the X-ray structure.. AB - ...
Fingerprint Dive into the research topics of Intratumoral Agreement of High-Resolution Magic Angle Spinning Magnetic Resonance Spectroscopic Profiles in the Metabolic Characterization of Breast Cancer. Together they form a unique fingerprint. ...
TY - JOUR. T1 - Carbon-13 Nuclear Magnetic Resonance Investigations of Phase Transitions and Phase Equilibria in Pure and Mixed Phospholipid Bilayers. AU - Wittebort, R. J.. AU - Blume, A.. AU - Huang, T. H.. AU - Das Gupta, S. K.. AU - Griffin, R. G.. PY - 1982/7. Y1 - 1982/7. N2 - The temperature dependence of the 13C NMR spectra of dipalmitoylphosphatidylethanolamine (DPPE) and three lecithins-dimyristoyl-, dipalmitoyl-, and distearoylphosphatidylcholine- which have been 13C-labeled at the sn-2 carbonyl has been studied. In the Lg or Lp phase, an axially symmetric powder pattern of about 100-ppm breadth is observed, and this transforms to an isotropic line at the main Lβ (Lβ) →Lα phase transition. In the case of DPPE, this transformation occurs precipitously and, with data from 2H spectra of 2H chain labeled DPPE, is shown to be due to a change in conformation at the sn-2 carbonyl. In contrast, the 13C=0 sn-2 spectra of lecithins exhibit a gradual transformation, beginning at ...
A method for determining properties of a mixture of fluids includes: (a) acquiring a plurality of nuclear magnetic resonance measurements from the mixture of fluids, each of the plurality of nuclear magnetic resonance measurements having a different value in an acquisition parameter for which at least one relaxation selected from the group consisting of longitudinal relaxation and transverse relaxation affects magnitudes of the nuclear magnetic resonance measurements; (b) generating a model of the mixture of fluids; (c) calculating a synthesized nuclear magnetic data set based on the model; (d) comparing the synthesized nuclear magnetic data set with the nuclear magnetic resonance measurements; and (e) adjusting the model and repeating (c) and (d), if difference between the synthesized nuclear magnetic data set and the nuclear magnetic measurements is greater than a minimum.
TY - JOUR. T1 - Photochemistry of cytosine derivatives. 2. Photohydration of cytosine derivatives. proton magnetic resonance study on the chemical structure and property of photohydrates. AU - Liu, Fu-Tong. PY - 1978. Y1 - 1978. N2 - Photohydrates of cytidine and cytidylic acids have been definitively characterized to be isomeric 6-hydroxy-5,6-dihydrocytosine derivatives. It has also been demonstrated by nuclear magnetic resonance spectroscopy that (1) the stereochemistry of photohydration is random, (2) the C5-H trans to the C6-OH undergoes a rapid selective exchange in the presence of proton acids, and (3) the dehydration of photohydrates is a trans-elimination. The mechanism of these processes is discussed.. AB - Photohydrates of cytidine and cytidylic acids have been definitively characterized to be isomeric 6-hydroxy-5,6-dihydrocytosine derivatives. It has also been demonstrated by nuclear magnetic resonance spectroscopy that (1) the stereochemistry of photohydration is random, (2) the C5-H ...
TY - JOUR. T1 - Nuclear magnetic relaxation dispersion studies of water‐soluble gadolinium(iii)‐texaphyrin complexes. AU - Geraldes, C. F.. AU - Sherry, A. D.. AU - Vallet, P.. AU - Maton, F.. AU - Muller, R. N.. AU - Mody, T. D.. AU - Hemmi, G.. AU - Sessler, J. L.. N1 - Copyright: Copyright 2016 Elsevier B.V., All rights reserved.. PY - 1995. Y1 - 1995. N2 - Water proton 1/T1 nuclear magnetic relaxation dispersion (NMRD) profiles were measured for a water‐soluble gadolinium(III) texaphyrin (Gd‐tex) complex as a function of temperature and in the presence and absence of 5% human serum albumin (HSA). Upon dissolving the complex in water (0.259 mM), the water relaxivity values decreased with time but remained higher than those of free Gd3+aqat all fields. Concurrent measurements of free Gd3+ using metallochromic dyes indicated that demetallation of the texaphyrin did not occur over a period of several days at 37°C. The high relaxivity values and shape of the NMRD profile of this complex ...
Natural and semi-synthetic compounds are being studied as novel phosphodiesterase 5 (PDE5) inhibitors for the treatment of erectile dysfunction, pulmonary hypertension, and lower urinary symptoms. Maclura pomifera is a source of flavonoids, one of the main classes of molecules investigated for these purposes. The extraction of the natural isoflavone osajin and its modification to obtain a semi-synthetic derivative are described in this short note. 1H and 13C-nuclear magnetic resonance spectroscopy (NMR), mass spectrometry, high-performance liquid chromatography (HPLC) and spectroscopic characterization of the title compound are also hereby provided. Two-dimensional (2D) nuclear Overhauser effect spectroscopy (NOESY) NMR, supported by in silico conformational studies, was used to achieve a complete assignment of the proton signals, assessing the correct chemical structure of the compound. Heteronuclear single quantum coherence spectroscopy (HSQC) and heteronuclear multiple bond correlation (HMBC) NMR
Magic Angle Spinning Nuclear Magnetic Resonance Characterization of Voltage-Dependent Anion Channel Gating in Two-Dimensional Lipid Crystalline Bilayers ...
TY - JOUR. T1 - High-precision measurement of hydrogen bond lengths in proteins by nuclear magnetic resonance methods. AU - Harris, Thomas K.. AU - Mildvan, Albert S.. PY - 1999/5/15. Y1 - 1999/5/15. N2 - We have compared hydrogen bond lengths on enzymes derived with high precision (≤ ±0.05 Å) from both the proton chemical shifts (δ) and the fractionation factors (φ) of the proton involved with those obtained from protein X-ray crystallography. Hydrogen bond distances derived from proton chemical shifts were obtained from a correlation of 59 O-H ···· O hydrogen bond lengths, measured by small molecule high-resolution X-ray crystallography, with chemical shifts determined by solid-state nuclear magnetic resonance (NMR) in the same crystals (McDermott A, Ridenour CF, Encyclopedia of NMR, Sussex, U.K.: Wiley, 1996:3820-3825). Hydrogen bond distances were independently obtained from fractionation factors that yield distances between the two proton wells in quartic double minimum potential ...
COSTA, Flávia Martins et al. Proton magnetic resonance spectroscopy and perfusion magnetic resonance imaging in the evaluation of musculoskeletal tumors. Radiol Bras [online]. 2009, vol.42, n.4, pp.215-223. ISSN 1678-7099. https://doi.org/10.1590/S0100-39842009000400006.. OBJECTIVE: To assess the role of proton magnetic resonance spectroscopy and dynamic contrast-enhanced magnetic resonance imaging in the differentiation between malignant and benign musculoskeletal tumors. MATERIALS AND METHODS: Fifty-five patients with musculoskeletal tumors (27 malignant and 28 benign) were studied. The examinations were performed in a 1.5 T magnetic resonance scanner with standard protocol, and single voxel proton magnetic resonance spectroscopy with 135 msec echo time. The dynamic contrast study was performed using T1-weighted gradient-echo sequence after intravenous gadolinium injection. Timesignal intensity curves and slope values were calculated. The statistical analysis was performed with the Levenes ...
A method for determining a pore characteristic of a substance includes the following steps: subjecting the substance to a substantially uniform static magnetic field; applying a magnetic pulse sequence to the substance, the pulse sequence being selected to produce nuclear magnetic resonance signals that are responsive to internal magnetic field inhomogeneities in the pore structure of the substance, and detecting, as measurement signals, nuclear magnetic resonance signals from the substance; applying a reference magnetic pulse sequence to the substance, the reference pulse sequence being selected to produce nuclear magnetic resonance signals that are substantially unresponsive to internal magnetic field inhomogeneities in the pore structure of the substance, and detecting, as reference measurement signals, nuclear magnetic resonance signals from the substance; and determining a pore characteristic of the substance from the measurement signals and the reference measurement signals.
TY - JOUR. T1 - Proton overhauser enhancements in human cardiac phosphorus NMR spectroscopy at 1.5 T. AU - Bottomley, Aul A.. AU - Hardy, Christopher J.. PY - 1992/4. Y1 - 1992/4. N2 - Narrowband irradiation of water protons with a surface coil yields significant nuclear Overhauser enhancement (nOe) of phosphocreatine (PCr) and some adenosine triphosphate (ATP) moieties in localized and unlocalized phosphorus (31P) NMR spectra from chest and heart muscle. In seven normal subjects at 1.5 T the nOe values were 0.6 ± 0.3, 0.6 ± 0.3, 0 ± 0.3, and 0.3 ± 0.2 for myocardial PCr, γ‐ATP, α‐ATP, and β‐ATP, respectively, not significantly different from those in chest muscle. Distortion of the measured PCr/ATP ratios due to differences in the nOe may require accurate correction to realize the full benefit of the effect in studies involving quantitative intergroup comparisons. © 1992 Academic Press, Inc.. AB - Narrowband irradiation of water protons with a surface coil yields significant ...
TY - JOUR. T1 - 31P nuclear magnetic resonance study of the proton-irradiated KTiOPO4 AU - Kim, Se Hun. AU - Lee, Cheol Eui. PY - 2013/10/17. Y1 - 2013/10/17. N2 - 31P nuclear magnetic resonance (NMR) was employed to study the effects of proton irradiation on KTiOPO4 (KTP) in view of the previously studied paramagnetic impurity doping effects. High-resolution 31P NMR measurements showed significant increase in the isotropic chemical shifts of the two inequivalent phosphorus sites in the proton-irradiated KTP system, indicating decrease in the electron density around the phosphorous nuclei. The 31P NMR linewidths of the KTP system manifested anomalies associated with the superionic transition and with the polaron formation, which became much weaker after proton irradiation. Besides, the activation energy of the charge carriers increased significantly after proton irradiation.. AB - 31P nuclear magnetic resonance (NMR) was employed to study the effects of proton irradiation on KTiOPO4 (KTP) in ...
High-resolution magic angle spinning proton (HRMAS 1H) magnetic resonance spectroscopy produces well-resolved spectra of metabolites from intact tissue specimens. Here we report the results of a preliminary study of 19 human brain tumors obtained by applying this method. Among these 19 cases were 2 low-grade astrocytomas, 1 anaplastic astrocytoma, 8 glioblastomas, 6 meningiomas, and 2 schwannomas. In addition, autopsy human brain tissues from two subjects without any known neurological diseases were used as normal controls. The HRMAS 1H magnetic resonance spectroscopy measurements were performed at 2°C on a 400-MHz NMR spectrometer with a HRMAS speed of 2.5 kHz. From these HRMAS 1H MR spectra, we measured the concentrations of 11 metabolites, the ratios of 15 metabolites (resonances) to creatine (at 3.03 ppm), and the spin-spin relaxation time for these metabolites (resonances). Our results indicate that these parameters have the potential to characterize tumor types and grades with statistical ...
TY - JOUR. T1 - Studies by 1H nuclear magnetic resonance and distance geometry of the solution conformation of the α-amylase inhibitor Tendamistat. AU - Kline, Allen D.. AU - Braun, Werner. AU - Wüthrich, Kurt. PY - 1986/5/20. Y1 - 1986/5/20. N2 - This is a preliminary report on the determination of the solution conformation of the α-amylase inhibitor Tendamistat by nuclear magnetic resonance and distance geometry calculations. A characterization is given of the complete polypeptide backbone fold and the side-chains of the presumed active site in this protein. These results are based on complete sequence-specific resonance assignments, a list of 401 distance constraints from nuclear Overhauser effects, 168 distance constraints from hydrogen bonds and disulphide bridges, and 50 torsion angle constraints from measurements of spin-spin coupling constants.. AB - This is a preliminary report on the determination of the solution conformation of the α-amylase inhibitor Tendamistat by nuclear ...
Solid state nuclear magnetic resonance studies of hydroxypropylmethylcellulose acetyl succinate polymer, a useful carrier in pharmaceutical solid dispersions. (deposited 07 Jan 2020 15:02) [Currently Displayed] ...
The Kingston Upon Hull Centre for Magnetic Resonance Investigations (CMRI), which opened in 1992, is a magnetic resonance imaging centre located in the city of Kingston upon Hull (Hull) in the East Riding of Yorkshire, England, UK. It is situated in the grounds of the Hull Royal Infirmary hospital in the centre of the city. The centre carries out both cancer research studies, under the auspices of the University of Hull, and clinical scanning, under the auspices of the local NHS trust, Hull and East Yorkshire Hospitals. The centre currently has three MRI scanners; two 1.5 tesla scanners owned by the NHS (a Philips Intera and a GE Signa) and a 3.0 tesla MR 750 GE Signa scanner owned by the University which was installed in January 2009 (one of the first 3.0 tesla whole-body capable systems in Europe). The medical research is carried out under the Directorship of Professor Lindsay W. Turnbull, and is devoted to the application of magnetic resonance imaging and magnetic resonance spectroscopy ...
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Preface XV. 1 Introduction 1. 1.1 Literature 8. 1.2 Units and Constants 9. References 10. Part I Basic Principles and Applications 11. 2 The Physical Basis of the Nuclear Magnetic Resonance Experiment.. Part I 13. 2.1 The Quantum Mechanical Model for the Isolated Proton 13. 2.2 Classical Description of the NMR Experiment 16. 2.3 Experimental Verification of Quantized Angular Momentum and of the Resonance Equation 17. 2.4 The NMR Experiment on Compact Matter and the Principle of the NMR Spectrometer 19. 2.4.1 How to Measure an NMR Spectrum 19. 2.5 Magnetic Properties of Nuclei beyond the Proton 25. References 27. 3 The Proton Magnetic Resonance Spectra of Organic Molecules - Chemical Shift and Spin-Spin Coupling 29. 3.1 The Chemical Shift 29. 3.1.1 Chemical Shift Measurements 32. 3.1.2 Integration of the Spectrum 35. 3.1.3 Structural Dependence of the Resonance Frequency - A General Survey 37. 3.2 Spin-Spin Coupling 41. 3.2.1 Simple Rules for the Interpretation of Multiplet Structures 46. 3.2.2 ...
1. One- and two-dimensional (correlated shift spectroscopy) high resolution proton n.m.r. spectra of human cerebrospinal fluid (CSF) are reported. The merits of water suppression by freeze drying or irradiation, and spectral simplification by spin-echo methods, are discussed. 2. Well-resolved resonances for a range of low molecular weight metabolites such as lactate, 3-d-hydroxybutyrate, alanine, acetate, citrate, glucose, valine and formate were observed. Resonances for glutamine were observed only from freeze dried samples. Concentrations determined by n.m.r. were in reasonable agreement with those from conventional methods. 3. The n.m.r. spectra of CSF were related to the clinical conditions of the subjects. No resonances for citrate were present in spectra of CSF from subjects (three infants) with bacterial meningitis; high lactate and lowered glucose levels were observed. Strong resonances for glucose and glycine were observed for mildly diabetic subjects. Both the aromatic and the ...
1. 31P n.m.r. spectroscopy was used to measure the dissociation constant of MgATP under simulated intracellular conditions and to measure erythrocyte free magnesium concentration.. 2. In a group of 40 subjects, the relationship between erythrocyte free magnesium and blood pressure, age and sex was examined by univariate and multivariate regression analysis.. 3. A weak positive association was found between erythrocyte free magnesium and mean blood pressure. This association was lost in a multivariate regression analysis including both age and sex.. 4. No significant relationship was found between erythrocyte free magnesium and age, sex, family history of hypertension or use of the combined oral contraceptive pill in the sample studied.. ...
Preface XV. 1 Introduction 1. 1.1 Literature 8. 1.2 Units and Constants 9. References 10. Part I Basic Principles and Applications 11. 2 The Physical Basis of the Nuclear Magnetic Resonance Experiment.. Part I 13. 2.1 The Quantum Mechanical Model for the Isolated Proton 13. 2.2 Classical Description of the NMR Experiment 16. 2.3 Experimental Verification of Quantized Angular Momentum and of the Resonance Equation 17. 2.4 The NMR Experiment on Compact Matter and the Principle of the NMR Spectrometer 19. 2.4.1 How to Measure an NMR Spectrum 19. 2.5 Magnetic Properties of Nuclei beyond the Proton 25. References 27. 3 The Proton Magnetic Resonance Spectra of Organic Molecules - Chemical Shift and Spin-Spin Coupling 29. 3.1 The Chemical Shift 29. 3.1.1 Chemical Shift Measurements 32. 3.1.2 Integration of the Spectrum 35. 3.1.3 Structural Dependence of the Resonance Frequency - A General Survey 37. 3.2 Spin-Spin Coupling 41. 3.2.1 Simple Rules for the Interpretation of Multiplet Structures 46. 3.2.2 ...
TY - JOUR. T1 - Proton magnetic resonance spectroscopy and intracranial tumours. T2 - Clinical perspectives. AU - Falini, Andrea. AU - Calabrese, Giovanna. AU - Origgi, Daniela. AU - Lipari, Susanna. AU - Triulzi, Fabio. AU - Losa, Marco. AU - Scotti, Giuseppe. PY - 1996. Y1 - 1996. N2 - Proton magnetic resonance spectroscopy ( 1H-MRS) was applied to characterize intracranial tumours of different hystological types. Seventy patients with intracranial neoplasms were studied before receiving surgery, radiotherapy or chemotherapy. All tumours were characterized by reduced or absent N-acetylaspartate and increased signal from choline-containing compounds. Distinctive patterns were observed only for primitive brain neo-plasms; high-grade gliomas were differentiated from low-grade ones by higher levels of choline-containing compounds. The metabolic aspects of metastatic lesions were similar to high-grade gliomas. These results, together with the limitations of 1H-MRS and future applications are ...
Measurement of myocardial iron is key to the clinical management of patients at risk of iron-overload cardiomyopathy, which is a major killer in transfusion-dependent patients and others with errors of iron metabolism. This applies especially to the large cohort of β-thalassemia major patients, in whom iron accumulation leads to damage in the liver, heart, and endocrine organs. Myocardial iron is assessed clinically with the cardiovascular magnetic resonance relaxation parameter T2*. This study describes the calibration of cardiovascular magnetic resonance relaxation against human iron concentration and the iron distribution throughout the heart under conditions of iron overload. A strong correlation was observed between cardiovascular magnetic resonance relaxation measurements and biochemically derived tissue iron concentration in 12 postmortem human hearts from transfusion-dependent patients, leading to a clinical calibration equation of [Fe]=45.0×(T2*)−1.22, where [Fe] is measured in ...
Law, W.S., Huang, P.Y., Li, S.F.Y., Ong, E.S., Ong, C.N., Sethi, S.K., Saw, S. (2009). Combination of1H nuclear magnetic resonance spectroscopy and liquid chromatography/mass spectrometry with pattern recognition techniques for evaluation of metabolic profile associated with albuminuria. Journal of Proteome Research 8 (4) : 1828-1837. [email protected] Repository. https://doi.org/10.1021/ ...
We aimed to elucidate the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats using in vivo magnetic resonance spectroscopy (MRS) and to determine their roles in the development of liver steatosis. Wistar rats received normal chow and either normal drinking water, or solutions containing 13% (w/v) glucose, 13% fructose, or 0.4% aspartame. After 7 weeks, in vivo hepatic dietary lipid uptake and de novo lipogenesis were assessed with proton-observed, carbon-13-edited MRS combined with 13C-labeled lipids and 13C-labeled glucose, respectively. The molecular basis of alterations in hepatic liver metabolism was analyzed in detail ex vivo using immunoblotting and targeted quantitative proteomics. Both glucose and fructose feeding increased adiposity, but only fructose induced hepatic lipid accumulation. In vivo MRS showed that this was not caused by increased hepatic uptake of dietary lipids, but could be attributed to an increase in de novo lipogenesis. Stimulation of lipogenesis
PURPOSE: Phosphorus magnetic resonance spectroscopy ((31)P-MRS) affords unique insight into cardiac energetics but has a low intrinsic signal-to-noise ratio (SNR) in humans. Theory predicts an increased (31)P-MRS SNR at 7T, offering exciting possibilities to better investigate cardiac metabolism. We therefore compare the performance of human cardiac (31)P-MRS at 7T to 3T, and measure T1s for (31)P metabolites at 7T. METHODS: Matched (31)P-MRS data were acquired at 3T and 7T, on nine normal volunteers. A novel Look-Locker CSI acquisition and fitting approach was used to measure T1s on six normal volunteers. RESULTS: T1s in the heart at 7T were: phosphocreatine (PCr) 3.05 ± 0.41s, γ-ATP 1.82 ± 0.09s, α-ATP 1.39 ± 0.09s, β-ATP 1.02 ± 0.17s and 2,3-DPG (2,3-diphosphoglycerate) 3.05 ± 0.41s (N = 6). In the field comparison (N = 9), PCr SNR increased 2.8× at 7T relative to 3T, the Cramer-Ráo uncertainty (CRLB) in PCr concentration decreased 2.4×, the mean CRLB in PCr/ATP decreased 2.7× and the PCr
Fluorination of oxide catalysts has been shown to drastically change the catalytic properties of these materials. The catalytic activity of these materials has been studied using a wide variety of reactions. Research on fluorinated oxides has focused upon improving product yields and product selectivity and upon obtaining a better understanding of the unmodified oxide catalyst as changes due to fluorination are observed. The purpose of this investigation has been to demonstarate the utility of pulsed nuclear magnetic resonance (NMR) spectroscopy as a direct spectroscopic probe of the local chemical environment of the hydroxyl groups and the fluorine atoms of these materials ...
Native human mammary MCF-7 adenocarcinoma cells and a subline displaying resistance to 4-hydroperoxycyclophosphamide, the chemically activated form of cyclophosphamide, were grown as multicellular spheroids or on a collagen sponge matrix and perfused for study by 31P and 13C nuclear magnetic resonance spectroscopy. The natural abundance 13C spectrum of the perfused cells exhibits well-resolved resonances due to the intracellular glutathione (GSH). The resistant cell line shows a higher intensity of the GSH 13C resonances, consistent with the increased GSH concentration determined from biochemical assays of extracts. Treatment of the resistant cell line with buthionine sulfoximine selectively diminishes the intensity of the GSH resonances in the 13C nuclear magnetic resonance spectrum.. ...
Neutrophil-activating protein-2 (NAP-2) is a 72 residue protein demonstrating a range of proinflammatory activities. The solution structure of monomeric NAP-2 has been investigated by two-dimensional 1H-n.m.r. spectroscopy. Sequence-specific proton resonance assignments have been made and secondary structural elements have been identified on the basis of nuclear Overhauser data, coupling constants and amide hydrogen/deuteron exchange. The NAP-2 monomer consists of a triple-stranded anti-parallel beta-sheet arranged in a Greek key and a C-terminal helix (residues 59-70) and is very similar to that found in the n.m.r. solution conformation of dimeric interleukin-8 and the crystal structure of tetrameric bovine platelet factor-4. Results are discussed in terms of heparin binding and neutrophil-activation properties of NAP-2. ...
Correlation spectroscopy is one of several types of two-dimensional nuclear magnetic resonance (NMR) spectroscopy. Other types of two-dimensional NMR include J-spectroscopy, exchange spectroscopy (EXSY), and Nuclear Overhauser effect spectroscopy (NOESY.) Two-dimensional NMR spectra provide more information about a molecule than one-dimensional NMR spectra and are especially useful in determining the structure of a molecule, particularly for molecules that are too complicated to work with using one-dimensional NMR. The first two-dimensional experiment, COSY, was proposed by Jean Jeener, a professor at Universit Libre de Bruxelles, in 1971. This experiment was later implemented by Walter P. Aue, Enrico Bartholdi and Richard R. Ernst, who published their work in 19761. A two-dimensional NMR experiment involves a series of one-dimensional experiments. Each experiment consists of a sequence of radio frequency pulses with delay periods in between them. It is the timing, frequencies, and intensities ...
The lactose transport protein (LacS) from Streptococcus thermophilus bearing a single cysteine mutation, K373C, within the putative interhelix loop 10-11 has been overexpressed in native membranes. Cross-polarization magic-angle spinning nuclear magnetic resonance spectroscopy (NMR) could selectively distinguish binding of (13)C-labeled substrate to just 50-60 nmol of LacS(K373C) in the native fluid membranes. Nitroxide electron spin-label at the K373C location was essentially immobile on the time scale of both conventional electron spin resonance spectroscopy (ESR) (|10(-8)s) and saturation-transfer ESR (|10(-3)s), under the same conditions as used in the NMR studies. The presence of the nitroxide spin-label effectively obscured the high-resolution NMR signal from bound substrate, even though (13)C-labeled substrate was shown to be within the binding center of the protein. The interhelix loop 10-11 is concluded to be in reasonably close proximity to the substrate binding site(s) of LacS (|15 A), and
Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement, Progress in Nuclear magnetic resonance spectroscopy 104, 12-55, (2018). by : J.-P. Korb [email protected] Abstract. The nuclear magnetic relaxation dispersion (NMRD) technique consists of measurement of the magnetic- field dependence of the longitudinal nuclear-spin-lattice relaxation rate 1/T1. Usually, the acquisition of the NMRD profiles is made using a fast field cycling (FFC) NMR technique that varies the magnetic field and explores a very large range of Larmor frequencies (10 kHz < x0/(2p) < 40 MHz). This allows extensive explorations of the fluctuations to which nuclear spin relaxation is sensitive. The FFC technique thus offers opportunities on multiple scales of both time and distance for characterizing the molecular dynam- ics and transport properties of complex liquids in bulk or embedded in confined environments. This review presents the principles, theories and ...
Interpretation Of Proton Nmr Spectra - 28 images - Chemistry Assignment Of 13c Nmr Spectra To Structural, Benchtop Nmr On Ibuprofen Molecules, How To Interpret Proton Nmr Spectra Thespectroscopy, Image Gallery Nmr Spectrum, Organic Spectroscopy International 1h Nmr
Apparatus is provided for coupled liquid chromatography and nuclear magnetic resonance (NMR) spectroscopy measurements. The apparatus includes a liquid chromatograph, an intermediate storage device for intermediately storing of components of a probe eluent and an NMR spectrometer. Selected intermediately stored components are fed to an NMR measurement unit. The intermediate storing device includes a number of capillary tubes, which are switchable by an automatically controlled valve arrangement for selectively receiving and delivering desired eluent components.
TY - JOUR. T1 - Magnetic Resonance Spectroscopy of the Breast. T2 - Current Status. AU - Bolan, Patrick J.. PY - 2013/8/1. Y1 - 2013/8/1. N2 - Invivo magnetic resonance spectroscopy (MRS) of the breast can be used to measure the level of choline-containing compounds, which is a biomarker of malignancy. In the diagnostic setting, MRS can provide high specificity for distinguishing benign from malignant lesions. MRS also can be used as an early response indicator in patients undergoing neoadjuvant chemotherapy. This article describes the acquisition and analysis methods used for measuring total choline levels in the breast using MRS, reviews the findings from clinical studies of diagnosis and treatment response, and discusses problems, limitations, and future developments for this promising clinical technology.. AB - Invivo magnetic resonance spectroscopy (MRS) of the breast can be used to measure the level of choline-containing compounds, which is a biomarker of malignancy. In the diagnostic ...
TY - JOUR. T1 - A study of spin-lattice relaxation rates of glucose, fructose, sucrose and cherries using high-T c SQUID-based NMR in ultralow magnetic fields. AU - Liao, Shu-Hsien. AU - Wu, Pei Che. PY - 2017/7/5. Y1 - 2017/7/5. N2 - We study the concentration dependence of spin-lattice relaxation rates, T 1 -1, of glucose, fructose, sucrose and cherries by using high-T c SQUID-based NMR at magnetic fields of ∼97 μT. The detected NMR signal, Sy (T Bp), is fitted to [1 - exp(-T Bp/T 1)] to derive T 1 -1, where Sy (T Bp) is the strength of the NMR signal, T Bp is the duration of pre-polarization and T 1 -1 is the spin-lattice relaxation rate. It was found that T 1 -1 increases as the sugar concentrations increase. The increased T 1 -1 is due to the presence of more molecules in the surroundings, which increases the spin-lattice interaction and in turn enhances T 1 -1. The T 1 -1versus degrees Brix curve provides a basis for determining unknown Brix values for cherries as well as other ...
Reply to: On the Correction of Effects of Flip Angle in 1H Magnetic Resonance Spectroscopy Signal Acquired Using Stimulated Echo Acquisition Mode ...
Subjects. NMR studies were performed with eight healthy volunteers (four males and four females; aged 29 ± 6; mean ± SD) at rest after a 12 hr overnight fasting. Informed written consent was obtained from all subjects after the aims and potential risks were explained to them. The protocol was approved by the Yale University School of Medicine Human Investigation Committee.. NMR acquisition. NMR data were acquired on a 2.1 T whole body (1 m bore) magnet connected to a modified Bruker AVANCE spectrometer (Bruker Instruments, Billerica, MA). Subjects remained supine in the magnet with the head lying on top of a home-built radio-frequency NMR probe, consisting of one13C circular coil (8.5 cm diameter) and two 1H quadrature coils for1H acquisitions and decoupling. After tuning, acquisition of scout images, shimming with the FASTERMAP procedure (Shen et al., 1997), and calibration of the decoupling power,13C NMR spectra were acquired for 10 min before and during a 160 min [2-13C] acetate infusion ...
Subjects. NMR studies were performed with eight healthy volunteers (four males and four females; aged 29 ± 6; mean ± SD) at rest after a 12 hr overnight fasting. Informed written consent was obtained from all subjects after the aims and potential risks were explained to them. The protocol was approved by the Yale University School of Medicine Human Investigation Committee.. NMR acquisition. NMR data were acquired on a 2.1 T whole body (1 m bore) magnet connected to a modified Bruker AVANCE spectrometer (Bruker Instruments, Billerica, MA). Subjects remained supine in the magnet with the head lying on top of a home-built radio-frequency NMR probe, consisting of one13C circular coil (8.5 cm diameter) and two 1H quadrature coils for1H acquisitions and decoupling. After tuning, acquisition of scout images, shimming with the FASTERMAP procedure (Shen et al., 1997), and calibration of the decoupling power,13C NMR spectra were acquired for 10 min before and during a 160 min [2-13C] acetate infusion ...
Advanced imaging of veterinary cancer patients has evolved in recent years and modalities once limited to human medicine have now been described for diagnostic purposes in veterinary medicine (positron emission tomography/computed tomography, single-photon emission computed tomography, whole body magnetic resonance imaging). Magnetic resonance spectroscopy (MRS) is a non-invasive and non-ionizing technique that is well described in the human medical literature and is most frequently used to evaluate the metabolic activity of tissues with questionable malignant transformation. Differentiation of neoplastic tissue from surrounding normal tissue is dependent on variations in cellular metabolism. Choline (Cho) levels have been described as diagnostic markers for malignancy for many different tumor types in vivo and ex vivo (tissue biopsies). Monitoring of pre- and post-therapy choline metabolites in tumors has also been performed to evaluate a patients response to cancer treatment. Positive ...
Abstract : We have developed new methods enabling in vivo localization and identification of metabolites through their (1)H NMR signatures, in a drosophila. Metabolic profiles in localized regions were obtained using HR-MAS Slice Localized Spectroscopy and Chemical Shift Imaging at high magnetic fields. These methods enabled measurement of metabolite contents in anatomic regions of the fly, demonstrated by a decrease in beta-alanine signals in the thorax of flies showing muscle degeneration.. ...
High resolution magic angle spinning (HRMAS) 1H NMR spectroscopy has been used to resolve different surface and in-pore solvent environments of ethylene carbonate (EC) and dimethyl carbonate (DMC) mixtures absorbed within nanoporous carbon (NPC). Two dimensional (2D) 1H HRMAS NMR exchange measurements revealed that the inhomogeneous broadened in-pore resonances have pore-to-pore exchange rates on the millisecond timescale. Pulsed-field gradient (PFG) NMR diffusometry revealed the in-pore self-diffusion constants for both EC and DMC were reduced by up to a factor of five with respect to the diffusion in the non-absorbed solvent mixtures. ...
Citrate was increased in the majority of gliomas in adult patients. The elevated citrate in our data indicates an altered metabolic state of tumor relative to healthy brain.
Nuclear magnetic resonance spectroscopy of stereoisomers most commonly known as NMR spectroscopy of stereoisomers is a chemical analysis method that uses NMR spectroscopy to determine the absolute configuration of stereoisomers. For example, the cis or trans alkenes, R or S enantiomers, and R,R or R,S diastereomers.[1][2] In a mixture of enantiomers, these methods can help quantify the optical purity by integrating the area under the NMR peak corresponding to each stereoisomer. Accuracy of integration can be improved by inserting a chiral derivatizing agent with a nucleus other than hydrogen or carbon, then reading the heteronuclear NMR spectrum: for example fluorine-19 NMR or phosphorus-31 NMR. Moshers acid contains a -CF3 group, so if the adduct has no other fluorine atoms, the 19F NMR of a racemic mixture shows just two peaks, one for each stereoisomer. As with NMR spectroscopy in general, good resolution requires a high signal-to-noise ratio, clear separation between peaks for each ...
Natural-abundance 13C nuclear magnetic resonance spectra of ten common nucleotides in neutral, aqueous solutions have been determined and interpreted. The spectra of two of these substances were also determined in acidic solutions, and several of the carbon chemical shifts were found to depend markedly on pH. Within the limited range of concentrations employed, there were observed no carbon chemical-shift changes which could be ascribed to base-stacking or base-pairing phenomena. ...
TY - JOUR. T1 - Proton and multinuclear magnetic resonance spectroscopy in the human brain at ultra-high field strength. T2 - A review. AU - Henning, Anke. PY - 2018/3. Y1 - 2018/3. N2 - Magnetic Resonance Spectroscopy (MRS) allows for a non-invasive and non-ionizing determination of in vivo tissue concentrations and metabolic turn-over rates of more than 20 metabolites and compounds in the central nervous system of humans. The aim of this review is to give a comprehensive overview about the advantages, challenges and advances of ultra-high field MRS with regard to methodological development, discoveries and applications from its beginnings around 15 years ago up to the current state. The review is limited to human brain and spinal cord application at field strength of 7T and 9.4T and includes all relevant nuclei (1H, 31P, 13C).. AB - Magnetic Resonance Spectroscopy (MRS) allows for a non-invasive and non-ionizing determination of in vivo tissue concentrations and metabolic turn-over rates of ...
Two new daphnane-type diterpene esters, yuanhuahine (1) and yuanhualine (2), were isolated from the flowers of Daphne genkwa (Thymelaeaceae) along with three known diterpene esters, yuanhuacine (3), yuanhuadine (4), and yuanhuagine (5). Their structures were determined by a combination of 1D and 2D NMR experiments, including correlation spectroscopy (COSY), heteronuclear multiple quantum correlation (HMQC), heteronuclear multiple bond correlation (HMBC), and rotating frame Overhauser enhancement spectroscopy (ROESY) sequences, and mass spectrometry. All the isolated compounds were tested against A549 human lung cancer cells and MRC-5 human normal lung epithelial cells. Compounds 1-5 exhibited potent anti-proliferative effects against A549 lung cancer cells with IC50 values of 12-53 nM, whereas these compounds were relatively non-cytotoxic against MRC-5 normal lung epithelial cells. © 2010 Pharmaceutical Society of Japan ...
In the search for novel chemical scaffolds leading to potential antihypertensive agents, the methanol extract of Murraya paniculata leaves was assessed for its effects on isolated rat aorta rings. The vasorelaxing effect of the chloroform fraction of the methanol plant extract was the most potent for its vasorelaxing activity on rat aorta rings contracted by 60 mM K(+) (K60). Two coumarins were isolated from the chloroform fraction: the novel kimcuongin (1) and the known murracarpin (2). Their structures were determined from spectroscopic evidences including (1)H- and (13)C-NMR, correlation spectroscopy (COSY), nuclear Overhauser effect spectroscopy (NOESY), heteronuclear multiple bond correlation (HMBC), heteronuclear single quantum correlation (HSQC), and high resolution mass spectrometry (HR-MS). Kimcuongin and, to a lesser extent, murracarpin, showed vasorelaxing activity with IC50 values of 37.7 µM and 139.3 µM, respectively. The coumarins kimcuongin and murracarpin may thus represent a ...
Detail záznamu - 1H magnetic resonance spectroscopy study of different histological types of human meningiomas in vitro - Detailné zobrazenie záznamu - Slovenská lekárska knižnica
TY - JOUR. T1 - Metabolic Characterization of Human Non-Hodgkins Lymphomas in Vivo with the Use of Proton-decoupled Phosphorus Magnetic Resonance Spectroscopy. AU - Negendank, William G.. AU - Padavic-Shaller, Kristin A.. AU - Li, Chun Wei. AU - Murphy-Boesch, Joseph. AU - Stoyanova, Radka. AU - Krigel, Robert L.. AU - Schilder, Russell J.. AU - Smith, Mitchell R.. AU - Brown, Truman R.. PY - 1995/8/1. Y1 - 1995/8/1. N2 - Development of biological and clinical uses of in vivo 31P magnetic resonance spectroscopy has been hampered by poor anatomic localization of spectra and poor resolution of overlapping signals within phosphomonoester and phosphodiester regions of the spectrum. We applied 1H decoupling and nuclear Overhauser enhancement to improve resolution of 31P magnetic resonance spectra accurately localized to 21 non-Hodgkins lymphomas (NHL) by using three-dimensional chemical shift imaging. All 21 spectra had large phosphomonoester signals (26% of total phosphorus) that contained high ...
sup13)C nuclear magnetic resonance spectroscopy was used to investigate citrate-glucose cometabolism in nongrowing cell suspensions of the wine lactic acid bacterium Leuconostoc oenos. The use of isotopically enriched substrates allowed us to identify and quantify in the end products the carbon atoms derived from each of the substrates supplied; furthermore, it was possible to differentiate between products derived from the metabolism of endogenous carbon reserves and those derived from external substrates. Citrate-sugar cometabolism was also monitored in dilute cell suspensions for comparison with the nuclear magnetic resonance results. A clear metabolic shift of the end products from glucose metabolism was observed when citrate was provided along with glucose: ethanol was replaced by acetate, and 2,3-butanediol was produced. Reciprocally, the production of lactate and 2,3-butanediol from citrate was increased in the presence of glucose. When citrate was cometabolized with glucose, a 10-fold ...
The chemical structures of isolated compounds were established on the basis of spectroscopical data as Infra-red (IR), 1D (1H, 13C, DEPT 135) and 2D-NMR experiments; Heteronuclear Multiple-Quantum Correlation (HMQC), correlation spectroscopy (COSY) and Heteronuclear Multiple Bond Correlation (HMBC) plus Mass Spectroscopy (MS) data. The 13C NMR data were assigned with the help of HMQC and DEPT 135 experiments while, the connectivitys of the molecular fragments were established by HMBC, COSY and NOESY. The analysis of the spectra and structure elucidation was also facilitated by comparison of observed and published 1H and 13C NMR data for the compounds.. Lysicamine (1): yellow needles (10.21 mg), m.p. 209-211°C, 1H NMR (CDCl3, 600 MHz) δ 7.57 (1H, s, H-3), 8.07 (1H, d, J = 5.2 Hz, H-4), 8.77 (1H, d, J = 5.2 Hz, H-5), 8.48 (1H, dd, J = 9.0, 1.8 Hz, H-8), 7.63 (1H, t, J = 9.0, 1.2 Hz, H-9), 7.86 (1H, t, J = 9.0, 1.4 Hz, H-10), 9.26 (1H, dd, J = 9.0, 1.2 Hz, H-11), 4.13 (3H, s, 1-OCH3), 4.06 (3H, ...
Virulence of Vibrio vulnificus has been strongly associated with encapsulation and an opaque colony morphology. Capsular polysaccharide was purified from a whole-cell, phosphate-buffered saline-extracted preparation of the opaque, virulent phase of V. vulnificus M06-24 (M06-24/O) by dialysis, centrifugation, enzymatic digestion, and phenol-chloroform extraction. Nuclear magnetic resonance spectroscopic analysis of the purified polysaccharide showed that the polymer was composed of a repeating structure with four sugar residues per repeating subunit: three residues of 2-acetamido-2,6-dideoxyhexopyranose in the alpha-gluco configuration (QuiNAc) and an additional residue of 2-acetamido hexouronate in the alpha-galactopyranose configuration (GalNAcA). The complete carbohydrate structure of the polysaccharide was determined by heteronuclear nuclear magnetic resonance spectroscopy and by high-performance anion-exchange chromatography. The 1H and 13C nuclear magnetic resonance spectra were completely ...
High-field proton NMR spectroscopic analysis of urine and plasma has been employed to study the biochemical effects and nephrotoxic action of an intramuscular dose of auranofin in rats. Auranofin induced a characteristic profile of proximal tubular damage as evidenced by aminoaciduria, lactic aciduria and increased urinary acetate concentrations. In addition, ethanol was detectable in both urine and plasma obtained from auranofin-treated rats. Auranofin-mediated elevations in the plasma and urine concentrations of 3-D-hydroxybutyrate indicated an increased utilisation of fats for fuel in rats treated with this novel therapeutic agent.. ...
Group IVA cytosolic phospholipase A2 (cPLA2α) plays an important role in tumorigenesis and angiogenesis. It is overexpressed in basal-like breast cancer (BLBC), which is aggressive and usually triple-negative, making it unresponsive to current targeted therapies. Here, we evaluated the anti-angiogenic effects of a specific cPLA2α inhibitor, AVX235, in a patient-derived triple-negative BLBC model. Mice bearing orthotopic xenografts received i.p. injections of AVX235 or DMSO vehicle daily for 1 week and then every other day for up to 19 days. Six treated and six control mice were terminated after 2 days of treatment, and the tumors excised for high resolution magic angle spinning magnetic resonance spectroscopy (HR MAS MRS) and prostaglandin E2 (PGE2) enzyme immunoassay (EIA) analysis. A 1-week imaging study was performed on a separate cohort of mice. Longitudinal dynamic contrast enhanced (DCE)-MRI was performed before, after 4 days, and after 1 week of treatment. The mice were then perfused with a
The highly interdisciplinary study of molecular magnetism spans a wide array of topics, ranging from spintronics and quantum computing to enzyme function and MRI contrast agents. At the core of all these fields is the study of materials whose properties can be controlled through the rational design of molecules. The chemical tailoring of molecular magnetic properties can only be achieved by understanding the relationship between the physical and electronic structures. In this dissertation, the interplay between structure and physical properties is probed using a variety of magnetic resonance techniques. In Chapter 1, we give a succinct overview of the various methods utilized in this dissertation. We first describe the experimental methods including electron paramagnetic resonance (EPR), 57Fe nuclear gamma resonance (Mössbauer) spectroscopy, electron double resonance detected nuclear magnetic resonance (ELDOR-NMR), and Fourier transform far-infrared (FTIR) spectroscopy. In addition to the ...
TY - JOUR. T1 - A tridentate CNO-donor palladium(II) complex as efficient catalyst for direct C―H arylation. T2 - Application in preparation of imidazole-based push-pull chromophores. AU - Li, Hui Hong. AU - Maitra, Ratnava. AU - Kuo, Ya Ting. AU - Chen, Jie Hong. AU - Hu, Ching Han. AU - Lee, Hon Man. PY - 2018/1. Y1 - 2018/1. N2 - A series of imidazolium chlorides for the formation of tridentate CNO-donor palladium(II) complexes featuring N-heterocyclic carbene moieties have been developed from cheap and readily available starting materials with high yields. Their palladium complexes were prepared by reactions between the ligand precursors and PdCl2 using K2CO3 as base in pyridine with reasonable yields. These air-stable metal complexes were characterized using 1H NMR and 13C{1H} NMR spectroscopy and elemental analyses. Heteronuclear multiple bond correlation experiments were performed to identify key NMR signals of these compounds. The structures of two of the complexes were also ...
Key words & phrases: isomer of C3H9N (CH3)2CHNH2 Interpreting the C-13 NMR spectra of propan-2-amine (2-aminopropane), C-13 nmr spectrum of propan-2-amine (2-aminopropane), understanding the carbon-13 nmr spectrum of propan-2-amine (2-aminopropane), explaining the line pattern in the high resolution C-13 nmr spectra of propan-2-amine (2-aminopropane), revising the C-13 nmr spectrum of propan-2-amine (2-aminopropane), ppm chemical shifts of the C-13 nmr spectrum of propan-2-amine (2-aminopropane), how to construct the diagram of the C-13 nmr spectrum of propan-2-amine (2-aminopropane), how to analyse the chemical shifts in the carbon-13 NMR spectrum of propan-2-amine (2-aminopropane) deducing the chemical environment of all the carbon atoms in propan-2-amine (2-aminopropane) examining the c13 nmr spectrum of propan-2-amine (2-aminopropane) analysing the 13-c nmr spectrum of propan-2-amine (2-aminopropane) how do you sketch and interpret the C-13 NMR spectrum of propan-2-amine (2-aminopropane) ...
TY - JOUR. T1 - Completing the circuit. T2 - Direct-observe 13C,15N double-quantum spectroscopy permits sequential resonance assignments near a paramagnetic center in acireductone dioxygenase. AU - Pochapsky, Susan Sondej. AU - Sunshine, Joel C.. AU - Pochapsky, Thomas C.. N1 - Copyright: Copyright 2010 Elsevier B.V., All rights reserved.. PY - 2008/2/20. Y1 - 2008/2/20. N2 - Acireductone dioxygenase (ARD) is a 179-residue enzyme containing a paramagnetic Ni+2 ion in the active site. Because of electron-nuclear spin interactions, 1H resonances within ∼9 Å of the Ni+2 are broadened beyond detection. For this reason, 1H-detected multidimensional NMR experiments are not suitable for structural characterization of the active site of ARD, and no isostructural diamagnetic homologue is available. Rapid recycle two-dimensional direct 13C detection NMR methods previously allowed correlation of carbonyl (13C′) carbons with directly bonded 13Cα and 15N spins in ARD (Kostic, M.; Pochapsky, S. S.; ...
Abstract: We present two-dimensional nuclear magnetic resonance spectroscopy protocols based on nitrogen-vacancy (NV) centers in diamond as efficient quantum sensors of protein structure. Continuous microwave driving fields are used to achieve Hartmann-Hahn resonances between NV spin sensor and proximate nuclei for selective control of nuclear spins and measurement of their polarization. Our protocols take advantage of the strong coupling between the NV sensor and the nuclei, thus facilitating coherence control of nuclear spins and relax the requirement of nuclear spin polarization. We dramatically reduce the experimental effort by employing a singular value thresholding matrix completion algorithm from signal processing to regain the resolution of protein structure based on sub-sampled data from NV based single molecule nuclear magnetic resonance spectroscopy. As an illustration, we demonstrate the power of this approach by identifying the nitrogen-Hydrogen interaction peak in an Alanine ...
B. Rajagopalan, W.J. McKenna, M.J. Blackledge, G.K. Radda; Measurement of Phosphorus Metabolism in Hypertrophic Cardiomyopathy by 31P Magnetic Resonance Spectroscopy. Clin Sci (Lond) 1 January 1988; 74 (s18): 9P. doi: https://doi.org/10.1042/cs074009P. Download citation file:. ...
Part I: Procedures and methodology -- Free energy simulations / M. Mezei, D.L. Beveridge -- Computer simulations of macromolecular dynamics : models for vibrational spectroscopy and x-ray refinement / Ronald M. Levy -- Nuclear magnetic resonance relaxation and the dynamics of proteins and membranes : theory and experiment / Attila Szabo -- Molecular dynamics simulation study of polypeptide conformational equilibria : a progress report / Amil Anderson, Mike Carson, Jan Hermans -- Conformational energy calculations on polypeptide and proteins : use of a statistical mechanical procedure for evaluating structure and properties / Harold A. Scheraga, Gregory H. Paine -- Computer simulation of DNA supercoiling / Wilma K. Olson, Janet Cicariello -- Calculation of atomic charges in large molecules / S. Shankar W.J. Mortier, S.K. Ghosh -- A vectorized near-neighbors algorithm of order N for molecular dynamics simulations / S.G. Lambrakos, J.P. Boris, I. Chandrasekhar [and others] -- A comment on ...
Deuterium isotope effects on 13C-NMR chemical shifts are investigated in a series of 10-hydroxybenzo[h]quinolines (HBQs) The OH proton is deuteriated. The isotope effects on 13C chemical shifts in these hydrogen bonded systems are rather unusual. The formal four-bond effects are found to be negative, indicating transmission via the hydrogen bond. In addition unusual long-range effects are seen. Structures, NMR chemical shifts and changes in nuclear shieldings upon deuteriation are calculated using DFT methods. Two-bond deuterium isotope effects on 13C chemical shifts are correlated with calculated OH stretching frequencies. Isotope effects on chemical shifts are calculated for systems with OH exchanged by OD. Hydrogen bond potentials are discussed. New and more soluble nitro derivatives are synthesized ...
13C and 1H NMR characterization of the sodium perchlorafe complex of a new tetraoxatetraaza lipophilic cage ligand (1) derived from 1,7-dioxa-4,10-diazacyclododecane has been performed. 1H homonuclear correlated and 1H J-resolved two-dimensional experiments allowed the recognition of resonances due to different types of OCH2CH2N fragments, and of those of the hydrogens of the bridging chains. 13C resonances have been assigned on the basis of a 13C1H heteronuclear correlated two-dimensional experiment, together with the 13C NMR spectra of the synthetic precursors of 1. 13C spin-lattice relaxation times and NOE measurements established that the unique relaxation mechanism is dipole-dipole; the calculated rotational correlation times indicated that molecular reorientation is isotropic. 13C spectra and relaxation times obtained in different solvents showed that specific solute-solvent interactions are absent.. ...
A new polymorphic form of ciprofloxacin saccharinate (CIP-SAC II) is presented, and compared with CIP-SAC I, a different polymorph which we had previously reported. The characterization techniques used were single crystal and powder X-ray diffraction, differential scanning calorimetry, thermogravimetry analysis and infrared and (13)C solid-state nuclear magnetic resonance spectroscopy. The results obtained from these techniques are consistent. Differential scanning calorimetry and thermogravimetric analysis showed that the reaction between the precursors is completed and the crystalline forms of both salts obtained (I and II) are highly pure. Infrared spectroscopy gave clear evidence of a salt formation. Solid-state nuclear magnetic resonance spectroscopy would indicate some degree of qualitative similarity in the intermolecular interaction scheme in both polymorphs, while thermal analysis data might indicate a difference in quantitative terms. A thorough single crystal structure determination ...
Despite the prevalence and impact of mild traumatic brain injury (mTBI), common clinical assessment methods for mTBI have insufficient sensitivity and specificity. Moreover, few researchers have attempted to document underlying changes in physiology as a function of recovery from mTBI. Proton magnet …
Quantitative, in-situ visualisation of metal ion dissolution and transport using 1H magnetic resonance imaging, J. M. Bray, A. J. Davenport, K. S. Ryder, M. M. Britton, Angew. Chem. Int. Ed., 55 (2016) 9394-97. Applications of magnetic resonance imaging to probe chemistry and flow in complex systems, M. M. Britton, Specialist Periodical Reports - Nuclear Magnetic Resonance volume 45 ed. V. Ramesh (2016). Location dependent coordination chemistry and MRI relaxivity, in de novo designed lanthanide coiled coils, M. R. Berwick, L. N. Slope, C. F. Smith, S. M. King, S. L. Newton, R. B. Gillis, G. G. Adams, A. J. Rowe, S. E. Harding, M. M. Britton, A. F. A. Peacock, Chem. Sci., 7 (2016) 2207-16. Probing composition and molecular mobility in thin spherical films using nuclear magnetic resonance measurements of diffusion, A. Vallatos, R. M. Kirsch, R. A. Williams, R. B. Hammond, X. Jia, U. Bröckel and M. M. Britton, Ind. Eng. Chem. Res., 54 (2015) 6825-6830.. Mapping B1-induced eddy current ...
TY - JOUR. T1 - A Nuclear Magnetic Resonance Study of Hydrogen Bonding in Tris(2-N-methylaminoethyl) Borate and Similar Compounds. AU - Meek, Devon W.. AU - Springer, Charles S.. PY - 1966/3. Y1 - 1966/3. N2 - Tris(2-aminoethyl) borate, B(OCH2CH2NH2)3, and the analogous N-methylamino and N,N-dimethylamino compounds have been prepared by the transesterification of methyl borate with the appropriate 2-aminoethanol. The nuclear magnetic resonance spectra show that extensive association of the terminal amino groups occurs in pure tris(N-methylaminoethyl) borate and that this association can be broken apart by heating to 160° or by dissolution in polar organic solvents such as triethylamine or acetonitrile. In order to determine whether the association results from hydrogen bonding or internal B-N coordination, several model systems have been investigated. The spectra of NH2C5H5-BF3, piperidine-BF3, and (C6H5)BO-CH2CH2NH2 in acetonitrile contain very complicated NCH2 peaks and broad NH peaks which ...
TY - JOUR. T1 - Nuclear magnetic resonance spin-lattice relaxation of lithium ions in aqueous solution by NMR and molecular dynamics. AU - Mohammadi, Mohaddese. AU - Benders, Stefan. AU - Jerschow, Alexej. N1 - Funding Information: This work was supported by the National Science Foundation under Award No. CBET 1804723. Publisher Copyright: © 2020 Author(s).. PY - 2020/11/14. Y1 - 2020/11/14. N2 - We study the aqueous solvation dynamics of lithium ions using nuclear magnetic resonance spectroscopy, molecular dynamics, and viscosity measurements. Several relaxation mechanisms are examined to explain the strong increases of spin-lattice relaxation toward high concentrations. The use of both 6Li and 7Li isotopes is helpful to identify the quadrupolar contribution to the relaxation rate. In particular, it is found that the quadrupolar interaction constitutes the strongest contribution above a concentration of ∼10 molal. The next-strongest contribution arises from interactions that scale with the ...
Bark samples isolated from brown coal deposits in Victoria, Australia, and buried wood from Rhizophora mangle have been studies by high-resolution solid-state nuclear magnetic resonance (NMR) techniques. Dipolar dephasing 13C NMR appears to be a useful method of detecting the presence of tannins in geochemical samples including barks, buried woods, peats and leaf litter. It is shown that tannins are selectively preserved in bark during coalification to the brown coal stage. ?? 1988....
The Tm3+ chelate of DOTAM [1,4,7,10-tetrakis(carbamoylmethyl)-1,4,7,10-tetraazacyclododecane] possessing sterically demanding t-butyl amide substitution favors TSAP geometry. This chelate displayed a paraCEST signal associated with the highly shifted amide proton signal at approximately −100 ppm that was beyond the frequency of macromolecule magnetization transfer. This signal also displayed high temperature dependence (0.57 ppm °C−1) in the range of 35-42 °C and at neutral pH. Copyright © 2013 John Wiley & Sons, Ltd. ...
Serogroup X Neisseria meningitidis (MenX) has recently emerged as a cause of localized disease outbreaks in sub-Saharan Africa. In order to prepare for vaccine development, MenX polysaccharide (MenX PS) was purified by standard methods and analyzed for identity and structure by NMR spectroscopy. This study presents the first full assignment of the structure of the MenX PS using (13)C, (1)H and (31)P NMR spectroscopy and total correlation spectroscopy (TOCSY) and (1)H-(13)C heteronuclear single quantum coherence (HSQC). Molecular size distribution analysis using HPLC-SEC with multi-angle laser light scattering (MALLS) found the single peak of MenX PS to have a weight-average molar mass of 247,000g/mol, slightly higher than a reference preparation of purified serogroup C meningococcal polysaccharide. MenX PS tended to be more thermostable than serogroup A PS. A method for the quantification of MenX PS was developed by use of high performance anion exchange chromatography with pulsed amperometric detection
BACKGROUND: In vivo hepatic phosphorus-31 magnetic resonance spectroscopy (31P MRS) provides biochemical information about phosphorus metabolism. AIM: To assess 31P MRS as a prognostic marker in patients with primary biliary cirrhosis (PBC) in relation to the current clinical prognostic models. PATIENTS AND METHODS: Twenty three patients with PBC of varying functional severity and 16 matched healthy volunteers were studied using in vivo 31P MRS. Spectra were acquired using a 1.5 T spectroscopy system. Peak area ratios of phosphomonoesters (PME), inorganic phosphate (Pi), and phosphodiesters (PDE) and nucleotide triphosphate (NTP) were calculated. Pugh score, Christensen prognostic index, and R value according to the Mayo model were calculated from the clinical data. RESULTS: The PME/NTP, Pi/NTP, PME/PDE, and PME/Pi ratios and the PME signal height ratio (SHR) were significantly higher, while the PDE/NTP and PDE/SHR were significantly lower in PBC patients compared with healthy volunteers (p , ...
There is continuing interest in understanding how fuel, fuel additives, and lubricants contribute to combustion chamber deposit (CCD) weights and compositions in order to better anticipate the impact of CCD on exhaust emissions and engine performance. For this reason, we have characterized a range of CCDs from bench engines and vehicles using solid state 13C Nuclear Magnetic Resonance Spectroscopy (NMR) and X-ray Photoelectron Spectroscopy (XPS). Differences in CCD composition and structure were related to the fuel, fuel additives, and engine oil used in the test. CCDs derived from most fuels run in modern engines are predominantly organic. The fraction of aromatic carbon ranges between 24 and 74% depending on fuels and test conditions over a test length of 1,000 to 20,000 miles. These aromatic carbons exist in predominantly 1 and 2 ring structures that are independent of the amount of aromatic carbon in the CCD. These 1 and 2 ring aromatic carbon units are even present in CCD produced from ...
On MR imaging, the white matter lesions, which could be seen in the subacute stage, but not in the acute or chronic stage, might represent edema due to postinfectious neuroallergic phenomena. Immunohistochemical detection of HSV antigen is depicted in B. The sparse amount of literature on proton magnetic resonance spectroscopy in patients with herpes simplex type 1 encephalitis is discussed. Here is MRI Brain with single voxel MRI Spectroscopy. MR spectra of bilateral temporal lobes were acquired by the single voxel method using 1.5T unit. We performed MR imaging and 1H MR spectroscopy of the brain in patients with different types of primary mitochondrial diseases to investigate the role of 1H MR spectroscopy in the clinical evaluation of these disorders. Theyre usually red in colour and will develop a white head.. Although the clinical picture has been well established for some time, clinical diagnosis is attained in only 20% of the cases. Although these conditions are similar with regard to ...
Carr−Purcell−Meiboom−Gill relaxation dispersion NMR spectroscopy has evolved into a powerful approach for the study of low populated, invisible conformations of biological molecules. One of the powerful features of the experiment is that chemical shift differences between the exchanging conformers can be obtained, providing structural information about invisible excited states. Through the development of new labeling approaches and NMR experiments it is now possible to measure backbone 13Cα and 13CO relaxation dispersion profiles in proteins without complications from 13C−13C couplings. Such measurements are presented here, along with those that probe exchange using 15N and 1HN nuclei. A key experimental design has been the choice of an exchanging system where excited-state chemical shifts were known from independent measurement. Thus it is possible to evaluate quantitatively the accuracy of chemical shift differences obtained in dispersion experiments and to establish that in general ...
Phosphorus-31 nuclear magnetic resonance spectroscopy can determine the status of high energy phosphates in vivo. However, its application to human cardiac studies requires precise spatial localization without significant contamination from other tissues. Using image-selected in-vivo spectroscopy (ISIS), a technique that allows three-dimensional localization of the volume of interest, 12 subjects were studied to determine the feasibility and reproducibility of phosphorus-31 spectroscopy of the human heart. Nuclear magnetic resonance imaging was performed using a commercial 1.5 tesla system to define the volume of interest.. Phosphorus-31 spectra were obtained from the septum and anteroapical region of the left ventricle in 10 studies. Relative peak heights and areas were determined for high energy phosphates. The mean phosphocreatine to adenosine triphosphate ratio was 1.33 ± 0.19 by height analysis and 1.23 ± 0.27 by area analysis. Duplicate measurements in four subjects showed a ...
A pulsed EPR saturation-recovery method has been used to measure spin-lattice relaxation times (T 1) for aminoxyl spin labels in cardiolipin bilayers, with and without cytochrome c. The relaxation time for each spin label was determined at various positions in the bilayer, which included the bilayer surface and three positions within the hydrophobia interior in the membrane, as well as a position close to the glycerol backbone of phospholipids in the bilayer. A dynamic profile for the hydrocarbon chains in bilayers was found in agreement with results from other techniques. On addition of cytochrome c to cardiolipin bilayers, changes in the spin-lattice relaxation time and order parameter were observed around the unsaturated region in the cardiolipin acyl chains. Supported by complementary lineshape analysis, these effects were interpreted as changes in the molecular dynamics around the double bonds in the acyl chains of cardiolipin bilayers, induced upon the binding of cytochrome
Routine measurement of adipose tissue composition by repeated biopsy invokes both ethical and practical difficulties, limiting long-term serial studies of adipose tissue composition. In vivo13C nuclear magnetic resonance (NMR) spectroscopy has been applied as a non-invasive alternative, although it has not as yet been fully validated. In this study we critically assess in vivo13C NMR spectroscopy and gas-liquid chromatography for the analysis of adipose tissue composition. The advantages and drawbacks of both methods are discussed, in particular to the study of adipose tissue during dietary manipulation and development. Our results show that the NMR measurements of adipose tissue composition are highly reproducible, but they can significantly differ from those obtained by gas-liquid chromatography (GLC) from the same volunteer. We show that the discrepancy between these two techniques arises from inherent limitations of both 13C NMR spectroscopy and GLC. Finally, we show that 13C NMR ...
We studied the in vivo cerebral metabolites and documented the presence of MECP2 gene mutations in six Chinese females with Rett syndrome. Magnetic resonance spectroscopy spectra from the frontal lobe (gray and white matter) and deep gray nuclei (basal ganglia and thalamus) of either side were obtained. N-acetylaspartate/total creatine, choline/total creatine, and N-acetylaspartate/choline ratios were analyzed and compared with six healthy age-matched female control subjects. MECP2 gene mutation was identified in four patients; one patient had polymorphism and one patient did not have gene mutation. N-acetylaspartate/total creatine of the frontal lobe of all patients (mean: 2.63, S.D. = 0.33) was decreased compared with age-matched control subjects (mean: 3.15, S.D. = 0.27), and the difference was statistically significant (P = 0.017) with a mean difference of 0.52 (95% CI = 0.68-0.36). The difference in all other metabolite ratios in the frontal lobe and deep gray nuclei were not statistically ...
1NTX: SECONDARY STRUCTURE DETERMINATION FOR ALPHA-NEUROTOXIN FROM DENDROASPIS POLYLEPIS POLYLEPIS BASED ON SEQUENCE SPECIFIC PROTON NUCLEAR MAGNETIC RESONANCE ASSIGNMENTS
STRUKTURAUFKLÄRUNG (ANALYTISCHE CHEMIE); COMPUTERANWENDUNGEN IN DER CHEMIE; KOHLENSTOFF-13-KERNRESONANZSPEKTROSKOPIE; PROTONEN-KERNRESONANZSPEKTROSKOPIE; INFRAROTSPEKTROSKOPIE; MASSENSPEKTROMETRIE; STRUCTURE DETERMINATION (ANALYTICAL CHEMISTRY); COMPUTER APPLICATIONS IN CHEMISTRY; CARBON-13 NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; PROTON NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; INFRARED SPECTROSCOPY; MASS ...
The requested funds are forthe purchase of a new400 MHz NMR spectrometer with high throughput capabilities to underpin current research acitivity and allow the development of several new research projects. The current facilities for organic chemists are notable to meet the future requirements. The new research projects are: (a) Synthesis and screening of natural and novel antibioticJanticanceragents; (b) new methodologiesfororganicsynthesis(includingtelescoped oxidation processes, new chiral diamine ligands and new ways of generating radicals; (c) Catalysis and clean organic chemistry (including catalytically active ionicliquids; silicon-supported guanidines and new oxidation catalysts) and (d) supramolecular and biological organ icchemistry (including functional models of meta lloenzymes, supramoleculardendrimer chemistry, nanotechnology and a combinatorial approach to glycoconjugates). Several proposals are linkedto funded research programmes while others represent new initiatives. ...
Synthesis of Imidazo[1,2-a]pyridines: Triflic Anhydride-Mediated Annulation of 2H … 5.1 Spectrometry in Organic Chemistry 5-4 Types of Spectrometry (5.1A) 5-5 Mass Spectrometry (MS) Nuclear Magnetic Resonance Spectrometry (NMR) Infrared Spectrometry (IR) Ultraviolet-Visible Spectrometry (UV-Vis) 5.2 Mass Spectrometry (MS) 5-6 Formation of Molecular and Fragment Ions (5.2A) 5-6 Molecular Ion In the 1,1-dichloroethane example all the coupling constants are 6.0 Hz, as illustrated by clicking on the spectrum. This is a Carbon 13 nmr then Proton nmr. A di-substituted benzene will have 4 protons in the AR region. First, spectra taken in benzene-d6 generally show small upfield shifts of most C-H signals, but in the case of acetone this shift is about five times larger than normal. Since no two magnets will have exactly the same field, resonance frequencies will vary accordingly and an alternative method for characterizing and specifying the location of nmr signals is needed. The isomeric pairs ...
In the Lake Champlain Basin, phosphorus (P) loading from streambank erosion and cropland are both important P sources, and a better understanding of the factors affecting riparian P loss is needed to help prioritize riparian restoration efforts. We utilized solution phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy and an enzyme hydrolysis method to characterize P and assess bioavailability in 14 commonly mapped riparian soils from northwestern Vermont. Surface horizons were sampled from distinct series at two riparian restoration sites to capture a range of soil properties. Samples were extracted with sodium hydroxide-ethylenediaminetetra-acetic acid (NaOH-EDTA) and analyzed by solution 31P NMR to speciate and quantify P compounds, and commercially available phosphatase enzymes were used to fractionate water-extractable molybdate unreactive P (MUP) into labile orthophosphate monoesters and orthophosphate diesters. Phosphorus extracted by NaOH-EDTA ranged from 74 to 510 mg P kg-1 ...
Blumenstein, Michael (1973) I. ³¹P and ¹³C Nuclear Magnetic Resonance Studies of Nicotinamide Adenine Denucleotide and Related Compounds. II. ¹⁹F Nuclear Magnetic Resonance Studies of Rabbit Muscle Glyceraldehyde-3-Phosphate Dehydrogenase Covalently Labeled with a Trifluoromethyl Group. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/0XYM-Z897. https://resolver.caltech.edu/CaltechTHESIS:11122019-135233564 ...
9. A magnetic resonance apparatus comprising:a magnetic resonance data acquisition unit comprising a basic field magnet that generates a basic magnetic field in an examination volume of the data acquisition unit;gradient coils in said data acquisition unit that generate gradient fields in the examination volume;a gradient coil unit that controls the gradient coils to generate said gradient fields;a radio-frequency transmitter that generates radio-frequency signals;a radio-frequency antenna system connected to said radio-frequency transmitter that radiates said radio-frequency signals into an examination subject located in said examination volume of said data acquisition unit, and that acquire radio-frequency signals from the examination subject that result from the radiated radio-frequency signals;a receiver unit connected to said antenna system that receives the detection radio-frequency signals;a control device that operates said gradient coil control unit, said receiver unit and said ...
TY - JOUR. T1 - Heme orientational heterogeneity in deuterohemin-reconstituted horse and human hemoglobin characterized by proton nuclear magnetic resonance spectroscopy. AU - Jue, Thomas. AU - La Mar, Gerd N.. PY - 1984/3/15. Y1 - 1984/3/15. N2 - The number of 2,4-H signals of met-cyano and deoxy deuteroheme-reconstituted sperm whale Mb are shown to reflect the known degree of heme rotational disorder in this modified protein. Using these unique spectral windows for the 2,4-H signals, we show that both horse and human Hb reconstituted with deuteroheme exhibit significant molecular heterogeneity which is consistent with approximately 20% heme rotational disorder within each subunit.. AB - The number of 2,4-H signals of met-cyano and deoxy deuteroheme-reconstituted sperm whale Mb are shown to reflect the known degree of heme rotational disorder in this modified protein. Using these unique spectral windows for the 2,4-H signals, we show that both horse and human Hb reconstituted with deuteroheme ...
In vivo nuclear magnetic resonance (NMR) spectroscopy is a non-invasive technique that can be used to investigate the metabolic response of plant tissues to anoxia. It has been used extensively in studies aimed at assessing the contribution of particular pathways to energy production and pH control during oxygen deprivation; and it is also a powerful method for investigating the origin and metabolic significance of the intracellular pH changes that occur in anoxic tissues. Recent NMR investigations of plant anaerobiosis are reviewed and it is concluded: (a) that the NMR approach provides a detailed description of the time-dependent interaction between some of the key pathways of carbon and nitrogen metabolism under anoxia; and (b) that it can provide strong evidence for the direct effect of pH on metabolism, and for the biochemical pH-stat model of the anoxic response. The significance of the NMR contribution to the understanding of plant anaerobiosis is discussed, and the possibility that the ...
The drive to develop better electrochemical energy storage devices requires the development of not only new materials, but also better understanding of the underpinning chemical and dynamical processes within such devices during operation, for which new analytical techniques are required. Currently, there are few techniques that can probe local composition and transport in the electrolyte during battery operation. In this paper, we report a novel application of magnetic resonance imaging (MRI) for probing electrochemical processes in a model electrochemical cell. Using MRI, the transport and zinc and oxygen electrochemistry in an alkaline electrolyte, typical of that found in zinc-air batteries, are investigated. Magnetic resonance relaxation maps of the electrolyte are used to visualize the chemical composition and electrochemical processes occurring during discharge in this model metal-air battery. Such experiments will be useful in the development of new energy storage/conversion devices, as ...
Compositional and structural changes within an electrolyte solution above an electrochemically active metal surface have been visualised using magnetic resonance imaging (MRI) for the first time. In these proof-of-concept experiments, zinc metal was galvanically corroded in a saturated lithium chloride solution. Magnetic resonance relaxation maps were taken during the corrosion process and spatial variations in both T1 and T2 relaxation times were observed to change with time. These changes were attributed to changes in the speciation of zinc ions in the electrolyte ...
Nuclear magnetic resonance (NMR) Nuclear magnetic resonance spectroscopy of carbohydrates Nuclear magnetic resonance ... ISBN 0-7216-3184-3. Pregosin, P. S.; Rueegger, H. (2004). "Nuclear magnetic resonance spectroscopy". In McCleverty, Jon A.; ... spectroscopy of nucleic acids Nuclear magnetic resonance spectroscopy of proteins Proton NMR Relaxation (NMR) Residual dipolar ... ISBN 0-7167-8759-8. Carrington, Alan; McLachlan, Andrew D. (1967). Introduction to Magnetic Resonance. Harper & Row. p. 47. the ...
... or near infrared spectroscopy (NIRS). Nuclear magnetic resonance (NMR) is what MRI and fMRI technologies were derived from, but ... magnetic resonance spectroscopy (for measuring some key metabolites such as N-acetylaspartate and lactate within the living ... transcranial magnetic stimulation, and nuclear magnetic resonance. To begin with, much of the recent progress has had to do not ... "Nuclear Magnetic Resonance Spectroscopy." Online at http://www.shu.ac.uk/schools/sci/chem/tutorials/molspec/nmr1.htm Shorey, ...
Nelson, J. H. (2003). Nuclear magnetic resonance spectroscopy. Prentice Hall. pp. 129-139. ISBN 978-0-13-033451-0. Danielson, ... Fluorine compounds are highly amenable to nuclear magnetic resonance (NMR), because fluorine-19 has a nuclear spin of 1⁄2, a ... Magnetic Resonance in Medicine. 39 (1): 85-88. doi:10.1002/mrm.1910390114. PMID 9438441. Gabriel, J. L.; Miller, T. F.; Wolfson ... high nuclear magnetic moment, and a high magnetogyric ratio. Fluorine compounds typically have a fast NMR relaxation, which ...
Nuclear Magnetic Resonance Spectroscopy. ISBN 978-0130334510. Garrou, Philip E. (1985). "Transition-Metal-Mediated Phosphorus- ... An important technique for the characterization of metal-PR3 complexes is 31P NMR spectroscopy. Substantial shifts occur upon ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 70: 25-49. doi:10.1016/j.pnmrs.2012.10.001. PMC 3613763. PMID 23540575. " ... Magnetic Resonance in Medicine. 71 (2): 561-569. doi:10.1002/mrm.24691. PMC 3718873. PMID 23447121. Yu, J.-X.; Hallac, R. R.; ... Magnetic Resonance in Medicine. 62 (2): 357-364. doi:10.1002/mrm.22020. PMC 4426862. PMID 19526495. Hallac, R. R.; Zhou, H.; ... Magnetic Resonance in Medicine. 71 (5): 1863-1873. doi:10.1002/mrm.24846. PMC 3883977. PMID 23813468. Zhang, Z.; Hallac, R. R ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 56 (4): 360-405. doi:10.1016/j.pnmrs.2010.03.002. PMC 2899824. PMID ... 2004 Fellow of the International Society of Magnetic Resonance, 2008 E. Bright Wilson Award in Spectroscopy by the American ... aka electron spin resonance) spectroscopy. He is the Frank and Robert Laughlin Professor of Physical Chemistry, Emeritus, at ... 2009 ISMAR Prize by the International Society of Magnetic Resonance, 2013 Joel Henry Hildebrand Award in the Chemistry of ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 80: 1-11. doi:10.1016/j.pnmrs.2014.03.001. PMC 4057650. PMID 24924264.CS1 ... Journal of Magnetic Resonance. 160 (1): 65-73. Bibcode:2003JMagR.160...65S. doi:10.1016/S1090-7807(02)00014-9. PMID 12565051. ... Elected Fellow of the International Society of Magnetic Resonance 2010: Elected Fellow of the American Academy of Arts and ... Encyclopedia of Magnetic Resonance. John Wiley & Sons. doi:10.1002/9780470034590. hdl:11693/53364. ISBN 9780470034590. "2014 ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 84-85: 14-32. doi:10.1016/j.pnmrs.2014.11.001. PMC 4325279. PMID 25669739 ... Bax, Ad (December 2011). "Triple resonance three-dimensional protein NMR: Before it became a black box". Journal of Magnetic ... Torchia, Dennis A. (2012). "Adventures in Biomolecular NMR". Encyclopedia of Magnetic Resonance. John Wiley & Sons. doi:10.1002 ... He received the Eastern Analytical Symposium Award for Outstanding Achievement in Nuclear Magnetic Resonance in 2013. " ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 31 (4): 293-315. doi:10.1016/s0079-6565(97)00007-1. Duckett, S. B.; Mewis ... "Detecting tumor response to treatment using hyperpolarized 13C magnetic resonance imaging and spectroscopy". Nat. Med. 13 (11 ... Hyperpolarized noble gases are typically used in magnetic resonance imaging (MRI) of the lungs. Hyperpolarized small molecules ... The magnetic field generating coils can be a pair of Helmholtz coils, used to generate the desired magnetic field strength, ...
Ammerlaan, C. A. J.; Kemp, R. V. (1985). "Magnetic resonance spectroscopy in semiconducting diamond". Journal of Physics C: ... The defects can be detected by different types of spectroscopy, including electron paramagnetic resonance (EPR), luminescence ... There is a tradition in diamond spectroscopy to label a defect-induced spectrum by a numbered acronym (e.g. GR1). This ... Baker, J.; Van Wyk, J.; Goss, J.; Briddon, P. (2008). "Electron paramagnetic resonance of sulfur at a split-vacancy site in ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 28 (1): 37-52. doi:10.1016/0079-6565(95)01019-X. Lécuyer, p. 101-103 ... They also were interested in nuclear magnetic resonance technology. One of Varian Associates' major contracts in the 1950s was ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 74: 1-32. doi:10.1016/j.pnmrs.2013.04.002. PMID 24083460.. ... Tofts, PS; Buckley, DL (1997). "Modeling tracer kinetics in dynamic Gd-DTPA MR imaging". Journal of Magnetic Resonance Imaging ... Magnetic Resonance Imaging. 5 (3): 201-08. doi:10.1016/0730-725X(87)90021-X. PMID 3626789. Cheng, K; Koeck, PJ; Elmlund, H; ... "Magnetic resonance diffusion-perfusion mismatch in acute ischemic stroke: An update". World Journal of Radiology. 4 (3): 63-74 ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 17: 33-67. doi:10.1016/0079-6565(85)80005-4. Kuhn, Lars T.; et al., eds. ( ... Goldman, Maurice (1970). Spin Temperature and Nuclear Magnetic Resonance in Solids. Oxford University Press. ISBN 978-0-19- ... 2008). "High-Field Dynamic Nuclear Polarization for Solid and Solution Biological NMR". Applied Magnetic Resonance. 34 (3-4): ... Applied Magnetic Resonance. 5 (2): 161-176. doi:10.1007/BF03162519. ISSN 0937-9347. Ni, Qing Zhe; Daviso E; Can TV; Markhasin E ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 11 (4): 211-272. doi:10.1016/0079-6565(77)80010-1. ISSN 0079-6565. ... Mantsch, Henry H.; Saitô, Hazime; Smith, Ian C. P. (1977). "Deuterium magnetic resonance, applications in chemistry, physics ... Deuterium NMR is NMR spectroscopy of deuterium (2H or D), an isotope of hydrogen. Deuterium is an isotope with spin = 1, unlike ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 26: 421-444. doi:10.1016/0079-6565(94)80012-X. Tolman, J. R. (2002). "A ... Magnetic dipole-dipole interaction Residual chemical shift anisotropy (rCSA) Solid-state nuclear magnetic resonance (ssNMR) ... Yannoni, C. S.; Ceasar, G. P.; Dailey, B. P. (1967). "Nuclear magnetic resonance spectrum of oriented (cyclobutadiene)iron ... 1964) Snyder, L. C. (1965). "Analysis of Nuclear Magnetic Resonance Spectra of Molecules in Liquid-Crystal Solvents". The ...
... where he applied both electron paramagnetic resonance (EPR) and Nuclear magnetic resonance spectroscopy (NMR) to the study of ... Antony John Williams is a British chemist and expert in the fields of both nuclear magnetic resonance (NMR) spectroscopy and ... Progress in Nuclear Magnetic Resonance Spectroscopy. 53 (1-2): 1-104. doi:10.1016/j.pnmrs.2007.04.003. Smurnyy, Y. D.; ... "Variable-temperature high-pressure investigation of the cobalt-59 NMR spectroscopy of aqueous K3\Co(CN)6]". Magnetic Resonance ...
Emsley, J. W.; Feeney, J.; Sutcliffe, L. H. (22 October 2013). High Resolution Nuclear Magnetic Resonance Spectroscopy. ... The angles ∠FSF and ∠FSO are 90°. The 19F nuclear magnetic resonance spectrum of SOF6 compared to SF6 has a -131.5 ppm shift ...
Wishart, DS (Feb 2011). "Interpreting protein chemical shift data". Progress in Nuclear Magnetic Resonance Spectroscopy. 58: 62 ... The Re-referenced Protein Chemical shift Database (RefDB) is an NMR spectroscopy database of carefully corrected or re- ...
SHIFTCOR Protein structure database NMR Nuclear magnetic resonance spectroscopy Protein nuclear magnetic resonance spectroscopy ... Wishart, DS (Feb 2011). "Interpreting protein chemical shift data". Progress in Nuclear Magnetic Resonance Spectroscopy. 58 (1- ... many biomolecular NMR spectroscopy labs use non-standard methods for determining the 1H, 13C or 15N "zero-point" chemical shift ... For protein NMR spectroscopy the recommended standard is DSS, which is insensitive to pH variations (unlike TSP). Furthermore, ...
Zhuravleva A, Korzhnev DM (May 2017). "Protein folding by NMR". Progress in Nuclear Magnetic Resonance Spectroscopy. 100: 52-77 ... Protein Nuclear Magnetic Resonance (NMR) is able to collect protein structural data by inducing a magnet field through samples ... As for fluorescence spectroscopy, circular-dichroism spectroscopy can be combined with fast-mixing devices such as stopped flow ... Fluorescence spectroscopy can be used to characterize the equilibrium unfolding of proteins by measuring the variation in the ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 48 (1): 47-62. doi:10.1016/j.pnmrs.2005.10.001. Schwieters, CD; Clore, GM ... Progress in Nuclear Magnetic Resonance Spectroscopy. 80: 1-11. doi:10.1016/j.pnmrs.2014.03.001. PMC 4057650. PMID 24924264. ... Restraints derived from all current solution and many solid state nuclear magnetic resonance (NMR) and X-ray scattering ...
... is a branch of biomolecular nuclear magnetic resonance spectroscopy that aims to accurately ... NMR chemical shifts are often called the mileposts of nuclear magnetic resonance spectroscopy. Chemists have used chemical ... Progress in Nuclear Magnetic Resonance Spectroscopy. 58 (1-2): 62-87. doi:10.1016/j.pnmrs.2010.07.004. PMID 21241884. Neal, S; ...
Yavari, I.; Roberts, J. D. (1978). "Nitrogen-15 Nuclear Magnetic Resonance Spectroscopy. Carbodiimides" (PDF). Journal of ...
Progress in Nuclear Magnetic Resonance Spectroscopy. 67: 1-48. doi:10.1016/j.pnmrs.2012.03.001.CS1 maint: uses authors ... Parahydrogen-induced polarization (PHIP) is a technique used in magnetic resonance imaging. The technique relies on the ... "The theory and practice of hyperpolarization in magnetic resonance using parahydrogen". ...
"Diffusion ordered nuclear magnetic resonance spectroscopy: principles and applications". Progress in Nuclear Magnetic Resonance ... and diffusion ordered nuclear magnetic resonance spectroscopy (DOSY). The apparent hydrodynamic size can then be used to ... Spectroscopy. 34: 203-256. doi:10.1016/S0079-6565(99)00003-5. Neufeld, R.; Stalke, D. (2015). "Accurate Molecular Weight ...
II Nuclear magnetic resonance spectroscopy (NMR). In addition to his use of NMR to determine magnetic susceptibilities of ... The determination of the paramagnetic susceptibility of substances in solution by nuclear magnetic resonance". Journal of the ... was an English chemist who made important contributions to nuclear magnetic resonance, magnetochemistry and other aspects of ... I. Measurement of magnetic susceptibility. For paramagnetic inorganic materials in particular, such measurements are often ...
"Introduction to Nuclear Magnetic Resonance Spectroscopy". Virtual Textbook of Organic Chemistry. Michigan State University. ... It is sometimes useful as a solvent for infrared spectroscopy, because there are no significant absorption bands above 1600 cm− ... Its use in NMR spectroscopy has been largely superseded by deuterated solvents. Use of carbon tetrachloride in determination of ... 1. Because carbon tetrachloride does not have any hydrogen atoms, it was historically used in proton NMR spectroscopy. In ...
Using magnetic resonance spectroscopy, it was discovered that they both had lead levels in their bones about 5-10 times more ... Weisskopf, Marc (2007). "Magnetic Resonance Spectroscopy and Environmental Toxicant Exposure". Annals of the New York Academy ...
Bachelard, edited by Herman (1997). Magnetic Resonance Spectroscopy and Imaging in Neurochemistry. Boston, MA: Springer Verlag ... "Magnetic Resonance Spectroscopy and Imaging in Neurochemistry.", and -as a co-editor- also "Neurochemistry : a practical ... C magnetic resonance spectroscopy". Journal of Neuroscience Research. 66 (5): 737-46. doi:10.1002/jnr.10053. PMID 11746397. ... "13-C In vivo magnetic resonance spectroscopy" to estimate glucose-oxidation metabolic rates in visual cortex during intense ...
for services to nuclear magnetic resonance spectroscopy. Leslie Edward George Smith, Chairman, British Oxygen Company ...
For the magnetic phenomenon, see Rayleigh law. For the stochastic distribution, see Rayleigh distribution. For the wireless ... For light frequencies well below the resonance frequency of the scattering particle (normal dispersion regime), the amount of ... Journal of Quantitative Spectroscopy and Radiative Transfer. 92 (3): 293-310. Bibcode:2005JQSRT..92..293S. doi:10.1016/j.jqsrt. ... "Laser spectroscopy of gas confined in nanoporous materials" (PDF). Applied Physics Letters. 96 (2): 021107. arXiv:0907.5092 ...
Andreev, S.V.; Letokhov, V.S.; Mishin, V.I. (1987). "Laser resonance photoionization spectroscopy of Rydberg levels in Fr". ... which may have significant impacts on their interior magnetic fields.[169][170] It has been estimated that the transition from ... it has been used in spectroscopy experiments, leading to more information regarding energy levels and the coupling constants ... "Spectroscopy with trapped francium: advances and perspectives for weak interaction studies". Rep. Prog. Phys. 69 (1): 79-118. ...
Assignments as a Basis for Determination of Spatial Protein Structures by High Resolution Proton Nuclear Magnetic Resonance" ( ... "Metabolic fingerprinting in disease diagnosis: biomedical applications of infrared and Raman spectroscopy". The Analyst 131 ...
... membrane proteins have been determined at atomic resolution by X-ray crystallography or nuclear magnetic resonance spectroscopy ...
Nucleic acid NMR is the use of nuclear magnetic resonance spectroscopy to obtain information about the structure and dynamics ... Applications for multidimensional nuclear magnetic resonance spectroscopy". Methods in Enzymology. 338: 261-283. doi:10.1016/ ... Robinson, B.H.; Drobny, G.P. (1995). "[19] Site-specific dynamics in DNA: Theory and experiment". Nuclear Magnetic Resonance ... Kan, Lou-sing; Ts'o, Paul O. P. (1986). "Nuclear Magnetic Resonance Studies of Nucleic Acids". In Chien, Shu; Ho, Chien (eds ...
"Diffusion ordered nuclear magnetic resonance spectroscopy: principles and applications". Progress in Nuclear Magnetic Resonance ... and diffusion ordered nuclear magnetic resonance spectroscopy (DOSY).[6] The apparent hydrodynamic size can then be used to ...
A well studied biradical is trimethylenemethane (TMM), C 4H 6. In 1966 Paul Dowd determined with electron spin resonance that ... The intermediate has been produced by reaction of oxygen radical anions with acetone and studied by photoelectron spectroscopy ... 200906666 PMID 20108294 Strong Exchange Interactions between Two Radicals Attached to Nonaromatic Spacers Deduced from Magnetic ...
Isidor Isaac Rabi (1898-1988): American physicist and Nobel Prize-winning scientist who discovered nuclear magnetic resonance ... Fay Ajzenberg-Selove (1926-2012): American nuclear physicist who was known for her experimental work in nuclear spectroscopy of ... Prize in Physiology or Medicine in 2003 with Peter Mansfield for his work which made the development of magnetic resonance ... position of Alan MacDiarmid Professor of Physical Sciences and was President of the International Society of Magnetic Resonance ...
Acoustic resonance spectroscopy. *Auger spectroscopy. *Astronomical spectroscopy. *Cavity ring-down spectroscopy. *Circular ... "FastTrack™ UV/VIS Spectroscopy" (PDF). www.mt.com. Mettler-Toledo AG, Analytical. 2016. Retrieved Dec 23, 2018.. ... Main article: Ultraviolet-visible spectroscopy. Most spectrophotometers are used in the UV and visible regions of the spectrum ... Spectrophotometry is a branch of electromagnetic spectroscopy concerned with the quantitative measurement of the reflection or ...
Nuclear magnetic resonance. Magic angle spinning. Two-dimensional nuclear magnetic resonance spectroscopy. Carbon-13 NMR. ... Atomic absorption spectroscopy. Fourier transform infrared spectroscopy. Ultraviolet-visible spectroscopy. Interferometry. ... Fundamental Spectroscopy. Raman spectroscopy. Rayleigh scattering. Fluorescence. Phosphorescence. Jablonski diagram. Emission ... Applied Spectroscopy Techniques. Inductively coupled plasma atomic emission spectroscopy. ...
The field enhancement is greatest when the plasmon frequency, ωp, is in resonance with the radiation (. ω. =. ω. p. /. 3. {\ ... Xu, X., Li, H., Hasan, D., Ruoff, R. S., Wang, A. X. and Fan, D. L. (2013), Near-Field Enhanced Plasmonic-Magnetic Bifunctional ... The term surface enhanced Raman spectroscopy implies that it provides the same information that traditional Raman spectroscopy ... "Surface-enhanced Raman spectroscopy on novel black silicon-based nanostructured surfaces". Journal of Raman Spectroscopy. 40 (8 ...
... nuclear magnetic resonance spectroscopy". Mol. Endocrinol. 6 (6): 904-13. DOI:10.1210/me.6.6.904. PMID 1495492. ...
"for his contributions to the development of the methodology of high resolution nuclear magnetic resonance (NMR) spectroscopy"[ ... for his development of nuclear magnetic resonance spectroscopy for determining the three-dimensional structure of biological ... "for his studies of the transition states of chemical reactions using femtosecond spectroscopy"[91] ...
There is an energy associated with a magnetic dipole moment in the presence of a magnetic field. For a nuclear magnetic dipole ... 2002). "Sub-Doppler Saturation Spectroscopy of HCN up to 1 THz and Detection of J. =. 3. ⟶. 2. (. 4. ⟶. 3. ). {\displaystyle J ... Electron paramagnetic resonance. References[edit]. *^ Shankland, Robert S. (1974). "Michelson and his interferometer". Physics ... The complete magnetic dipole contribution to the hyperfine Hamiltonian is thus given by: H. ^. D. =. 2. g. I. μ. N. μ. B. μ. 0 ...
... nuclear magnetic resonance and mass spectrometry. ... methods include X-ray crystallography and NMR spectroscopy, ... Resonance structures of the peptide bond that links individual amino acids to form a protein polymer ... The peptide bond has two resonance forms that contribute some double-bond character and inhibit rotation around its axis, so ... by spectroscopy if the protein has distinguishable spectroscopic features, or by enzyme assays if the protein has enzymatic ...
Magnesite Magnesium magnetic resonance magnetism Magnetite Malachite Malacolite Manfred Eigen Manganese Marble Marcasite Marie ... X-ray photoelectron spectroscopy xenon Xenotime YBCO Ytterbium Yttria Yttrium Yuan T. Lee Zeolite Zinc Zinnwaldite Zircon ... Nitrogen dioxide Nitroglycerine Nitrous oxide Nobel Prize in Chemistry Nobelium Noble gas Nonmetal nuclear magnetic resonance ... Ulexite UN number Uralite Uraninite Uranium Urea Uric acid UV/VIS spectroscopy Valence Van der Waals radius Van der Waals force ...
"for his contributions to the development of the methodology of high resolution nuclear magnetic resonance (NMR) spectroscopy"[ ... for his development of nuclear magnetic resonance spectroscopy for determining the three-dimensional structure of biological ... "for his studies of the transition states of chemical reactions using femtosecond spectroscopy"[98] ...
... magnetic resonance imaging (MRI), diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS), positron emission ...
... of cerebral oxygenation changes during brain activation by near-infrared spectroscopy and functional magnetic resonance imaging ... The functional magnetic resonance imaging (fMRI) machine uses the signal from deoxyhemoglobin, which is sensitive to magnetic ... "Functional brain mapping by blood oxygenation level-dependent contrast magnetic resonance imaging. A comparison of signal ... Deoxygenated hemoglobin is paramagnetic; it is weakly attracted to magnetic fields.[49][50] In contrast, oxygenated hemoglobin ...
... effective negative magnetic permeability is achievable when polariton resonance exists. To achieve a negative index of ... "Spectroscopy of metamaterials from infrared to optical frequencies" (PDF). Journal of the Optical Society of America B. 23 (3 ... which now has an effective magnetic permeability μeff in response to the radiated-incident magnetic field.[5] ... Looking at the make-up of the split ring, the associated magnetic field pattern from the SRR is dipolar. This dipolar behavior ...
Magnetic resonance imaging (MRI) uses magnetic fields and radio waves to produce high quality two- or three-dimensional images ... Whereas techniques such as diffuse optical imaging (DOT) and near-infrared spectroscopy (NIRS) measure optical absorption of ... Functional magnetic resonance imagingEdit. Axial MRI slice at the level of the basal ganglia, showing fMRI BOLD signal changes ... Functional Magnetic Resonance Imaging (fMRI)Edit. fMRI is commonly classified as a minimally-to-moderate risk due to its non- ...
Quantitative proton magnetic resonance spectroscopy (MRS) is a noninvasive analytical technique that has been used to study ... Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to visualize internal structures of the body ... MRI makes use of the property of nuclear magnetic resonance (NMR) to image nuclei of atoms inside the body. This method is ...
Plasma diagnostics, Self Excited Electron Plasma Resonance Spectroscopy (SEERS). *Plasma display. *Plasma effect ... Magnetic radiation reaction force. *Magnetic reconnection. *Magnetic Reynolds number. *Magnetic sail, Mini-magnetospheric ...
... nuclear magnetic resonance, and high performance liquid chromatography. The result of the analysis showed that the calculus was ... and Processed Foods Using Surface Enhanced Raman Spectroscopy and HPLC". Journal of Food Science. 73 (8): T129. doi:10.1111/j. ... another procedure is based on surface-enhanced Raman spectroscopy (SERS).[83][84] ... and melamine cyanurate using surface enhanced Raman spectroscopy coupled with gold nanosubstrates". Sensing and Instrumentation ...
... of cerebral oxygenation changes during brain activation by near-infrared spectroscopy and functional magnetic resonance imaging ... Astronomical spectroscopyEdit. Near-infrared spectroscopy is in astronomy for studying the atmospheres of cool stars where ... Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum ... 2007). Handbook of Near-Infrared Analysis, Third Edition (Practical Spectroscopy). pp. 349-369. ISBN 9781420007374.. ...
Carbon-13 and nitrogen-15 nuclear magnetic resonance[edit]. Main article: Triple-resonance nuclear magnetic resonance ... NMR spectroscopy on large proteins[edit]. Traditionally, nuclear magnetic resonance spectroscopy has been limited to relatively ... Resonance assignment[edit]. In order to analyze the nuclear magnetic resonance data, it is important to get a resonance ... "Validation of protein structures derived by NMR spectroscopy". Progress in Nuclear Magnetic Resonance Spectroscopy. 45 (3-4): ...
en: Magnetic Resonance Spectroscopy, Imaging and Applications: NMR, NMRI and ESR, Minuteman Press, USA, 2010;pp.204 ... Nuclear Magnetic Resonance Fourier Transform (2D-FT) Spectroscopy. Nobel Lecture, pe 9 Decembrie,1992. ... en: Magnetic Resonance Spectroscopy, Imaging and Applications: NMR, NMRI and ESR, Minuteman Press, USA, 2010;pp.204. http:// ... J.M Tyszka, S.E Fraser, R.E Jacobs (2005). „en: Magnetic Resonance Microscopy: Recent Advances and Applications.". Current ...
"Physics of Magnetic Flux Ropes: 439-453.. *^ Mészáros, Péter (2010) The High Energy Universe: Ultra-High Energy Events in ... Inductively coupled plasmas (ICP), formed typically in argon gas for optical emission spectroscopy or mass spectrometry ... Examples include helicon discharge and electron cyclotron resonance (ECR).[75] ... the electrons but not the ions are trapped by the magnetic field), non-magnetized (the magnetic field is too weak to trap the ...
Magnetic induction accelerators accelerate particles by induction from an increasing magnetic field, as if the particles were ... High-energy X-rays are useful for X-ray spectroscopy of proteins or X-ray absorption fine structure (XAFS), for example. ... In such a structure, the accelerating field's frequency (and the cyclotron resonance frequency) is kept constant for all ... The increasing magnetic field creates a circulating electric field which can be configured to accelerate the particles. ...
"Electric and magnetic properties of carbon monoxide by molecular-beam electric-resonance spectroscopy". Chemical Physics. 22 (2 ... Metal carbonyls in coordination chemistry are usually studied using infrared spectroscopy.. Organic and main group chemistry[ ... Gilliam, O. R.; Johnson, C. M.; Gordy, W. (1950). "Microwave Spectroscopy in the Region from Two to Three Millimeters". ...
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a ... Biomolecular NMR spectroscopy[edit]. Proteins[edit]. Main article: Nuclear magnetic resonance spectroscopy of proteins ... "Diffusion ordered nuclear magnetic resonance spectroscopy: principles and applications". Progress in Nuclear Magnetic Resonance ... Correlation spectroscopy is one of several types of two-dimensional nuclear magnetic resonance (NMR) spectroscopy or 2D-NMR. ...
Katrin H. Preller, Thomas Pokorny, Andreas Hock, Rainer Kraehenmann, Philipp Stämpfli, Erich Seifritz, Milan Scheidegger, and Franz X. Vollenweider ...
The combination of our electron spin based magnetic resonance and solid-state device electrical characterization skill sets are ... The Magnetic Resonance Spectroscopy Project strives to be at the forefront of understanding the roles that critical atomic- ... The Magnetic Resonance Spectroscopy Project strives to be at the forefront of understanding the roles that critical atomic- ... The Magnetic Resonance Spectroscopy Project leverages the most powerful analytical tool available to accomplish this goal; ...
Carbon-13 and nitrogen-15 nuclear magnetic resonance[edit]. Main article: Triple-resonance nuclear magnetic resonance ... NMR spectroscopy on large proteins[edit]. Traditionally, nuclear magnetic resonance spectroscopy has been limited to relatively ... Resonance assignment[edit]. In order to analyze the nuclear magnetic resonance data, it is important to get a resonance ... "Validation of protein structures derived by NMR spectroscopy". Progress in Nuclear Magnetic Resonance Spectroscopy. 45 (3-4): ...
How might magnetic resonance spectroscopy be used to determine a probable CTE diagnosis in living patients? ... Proton magnetic resonance spectroscopy (MRS) may be one tool to support an in-life diagnosis of CTE. MRS is a safe and ... Magnetic Resonance Spectroscopy as a Biomarker for Chronic Traumatic Encephalopathy. Michael L. Alosco, PhD; Johnny Jarnagin, ... Proton magnetic resonance spectroscopy (MRS) measures brain tissue metabolism in vivo and could facilitate a "probable CTE" ...
Nuclear magnetic resonance spectroscopy Handout Duration : 32 pages Buy Modern Chemical Techniques: £19.95 Website ... Practical chemistryEquipment, apparatus & instrumentsAnalysis: qualitativeSpectroscopyMagnetic resonanceMedical applications ... Modern chemical techniques: ultraviolet/visible spectroscopy Modern chemical techniques: infrared spectroscopy. Modern chemical ... Spectroscopy in a Suitcase (SIAS) Laboratory and Pilot Plant Tours SpectraSchool. Assessment for Learning Chemistry: How can ...
RMITs Nuclear Magnetic Resonance Spectroscopy Facility houses a range of solid and solution state nuclear magnetic resonance ... RMITs Nuclear Magnetic Resonance Spectroscopy Facility houses a range of solid and solution state nuclear magnetic resonance ... Home / About RMIT / Our locations and facilities / Facilities / Research Facilities / Nuclear Magnetic Resonance Spectroscopy ... Nuclear magnetic resonance (NMR) spectroscopy is a sophisticated and powerful yet non-destructive technique that employs strong ...
Using a revolutionary technique known as magnetic resonance spectroscopy, doctors can now measure the amount of fat inside an ... Magnetic resonance spectroscopy is based on the same principles as magnetic resonance imaging (MRI), but goes a step further: ... Szczepaniak-a physicist by training and now director of magnetic resonance spectroscopy at the Cedars-Sinai Heart Institute-in ... Using a revolutionary research technique known as magnetic resonance spectroscopy, Dr. Szczepniak can measure the amount of fat ...
Magnetic resonance spectroscopy (MRS) or spectroscopic imaging (MRSI) enables the detection of metabolites, amino acids, and ... Magnetic resonance spectroscopy (MRS) or spectroscopic imaging (MRSI) enables the detection of metabolites, amino acids, and ... Cheng M., Glunde K. (2018) Magnetic Resonance Spectroscopy Studies of Mouse Models of Cancer. In: García Martín M., López ... Serkova NJ, Brown MS (2012) Quantitative analysis in magnetic resonance spectroscopy: from metabolic profiling to in vivo ...
Webinars , Nuclear Magnetic Resonance (NMR) Spectroscopy Nuclear Magnetic Resonance (NMR) Spectroscopy Webinars. *Alzheimers ... High speed spectroscopy - New AVANCE NEO The Bruker AVANCE III HD delivered cutting-edge, sophisticated NMR performance that ... Chemical Reaction Monitoring with Easy On-The-Fly NMR Spectroscopy NMR is becoming an increasingly important tool for the ... This webinar will introduce a technique called 2D heteronuclear single quantum coherence (HSQC) NMR spectroscopy for assessing ...
Proton magnetic resonance spectroscopy has demonstrated neural damages in the left lenticular nucleus in a group of patients ... Proton magnetic resonance spectroscopy has demonstrated neural damages in the left lenticular nucleus in a group of patients ... What findings on proton magnetic resonance spectroscopy suggest tardive dyskinesia (TD)?. Updated: Oct 17, 2018 ...
Magnetic resonance imaging and spectroscopy for monitoring liver steatosis.. Cowin GJ1, Jonsson JR, Bauer JD, Ash S, Ali A, ... To compare noninvasive MRI and magnetic resonance spectroscopy (MRS) methods with liver biopsy to quantify liver fat content. ... Centre for Magnetic Resonance, University of Queensland, Queensland, Australia. [email protected] ...
Here we report a method, combining deep learning and sparse matrix completion, to speed up 2D nanoscale NMR spectroscopy. The ... Two-dimensional nuclear magnetic resonance (NMR) is indispensable to molecule structure determination. Nitrogen-vacancy center ... Two-dimensional nuclear magnetic resonance spectroscopy with a microfluidic diamond quantum sensor. Sci. Adv. 5, eaaw7895 (2019 ... Accelerated 2d magnetic resonance spectroscopy of single spins using matrix completion. Sci. Rep. 5, 17728 (2015). ...
Nuclear Magnetic Resonance Spectroscopy. Nuclear Magnetic Resonance Spectroscopy. ... The technique known as nuclear magnetic resonance (NMR) is based on the interaction of the magnetic properties of nuclei with ... NMR spectroscopy is at the center of most strategies for solving structural problems in all fields of chemistry. ...
9780124016880 Our cheapest price for Magnetic Resonance Spectroscopy: Tools for Neuroscience Research and is $110.19. Free ... Magnetic Resonance Spectroscopy: Tools for Neuroscience Research and Emerging Clinical Applications. by Stagg, Charlotte J. * ...
Contemporary 1H-magnetic resonance spectroscopy (MRS) techniques can estimate the levels of brain metabolites with a high ... reproducibility and add only 10 minutes to a routine or volumetric magnetic... ... Sclerosis Mild Cognitive Impairment Magnetic Resonance Spectroscopy Temporal Lobe Epilepsy Magnetic Resonance Spectroscopy ... In-vivo proton magnetic resonance spectroscopy studies of human brain. Magn Reson Imaging 1991; 9: 303-8PubMedCrossRefGoogle ...
... magnetic resonance spectroscopy (MRS), and Nottingham Prognostic Index (NPI), LDH-A and proliferative marker Ki-67 were ... Lactate concentration in breast cancer using advanced magnetic resonance spectroscopy. *Sai Man Cheung. 1. na1, ... Metabolic profiles of human brain tumors using quantitative in vivo 1H magnetic resonance spectroscopy. Magn. Reson. Med. 49, ... a software package for quantitation of in vivo/medical magnetic resonance spectroscopy signals. Comput. Biol. Med. 31, 269-286 ...
Magnetic resonance spectroscopy (MRS) is a companion technique to the more familiar magnetic resonance imaging (MRI) scan. ... Magnetic Resonance Spectroscopy Studies of Human Metabolism Message Subject (Your Name) has forwarded a page to you from ... Observation of intramyocellular lipids by 1H-magnetic resonance spectroscopy. Ann N Y Acad Sci 2000;904:25-31pmid:10865706. ... 1-(13)C glucose magnetic resonance spectroscopy of pediatric and adult brain disorders. NMR Biomed 2001;14:19-32pmid:11252037. ...
... fees and contact details for Magnetic Resonance Imaging and Spectroscopy at University of Nottingham on prospects.ac.uk ... Magnetic Resonance Imaging and Spectroscopy. Institution. University of Nottingham · School of Physics and Astronomy. ... Magnetic Resonance Imaging and Spectroscopy. Institution. University of Nottingham · School of Physics and Astronomy. ... Magnetic resonance imaging (MRI), which was invented at The University of Nottingham by Nobel laureate Sir Peter Mansfield, has ...
... Polymer characterisation by Nuclear Magnetic Resonance ... Polymer characterisation by Nuclear Magnetic Resonance Spectroscopy (NMR) provides detailed structural information for product ... Spectroscopy (NMR) provides detailed structural information for product development and QC. ...
... spectroscopy is used to elucidation and confirmation of structures. Introduction of Nuclear Magnetic Resonance Spectroscopy for ... spectroscopy is used to elucidation and confirmation of structures. Introduction of Nuclear Magnetic Resonance Spectroscopy for ... the Nuclear Magnetic Resonance may collect and analyze the eluted peak. The Nuclear Magnetic Resonance in conjunction with ... Other than Nuclear Magnetic Resonance, techniques based on Raman or Infra-red spectroscopy are useful in examining paperwork, ...
Cancer Magnetic Resonance Spectroscopy: Clinical and Research Applications. Organizers: N.R. Jagannathan, Ph.D. and Daniel B. ...
Introduction to Molecular Spectroscopy. This week we concentrate on Nuclear Magnetic Resonance (NMR) spectroscopy. Here a ... magnetic field is used to create energy levels for magnetic ... ... Nuclear Magnetic Resonance (NMR) Spectroscopy. This week we ... These are UV/Visible , Infra-red (IR) and Nuclear Magnetic Resonance (NMR) spectroscopies. The content is presented using short ... concentrate on Nuclear Magnetic Resonance (NMR) spectroscopy. Here a magnetic field is used to create energy levels for ...
... and magnetic resonance spectroscopy (MRS) are diagnostic tests that allow researchers to l... ... Magnetic resonance imaging (. MRI) and magnetic resonance spectroscopy (MRS) are diagnostic tests that allow researchers to ... diseases with magnetic resonance imaging. Researchers will attempt different magnetic resonance imaging methods and techniques ... Magnetic resonance imaging and spectroscopy studies can be used to gather or evaluate information about various aspects of ...
Nuclear Magnetic Resonance Fourier Transform Spectroscopy. Read the Nobel Lecture. Pdf 1.45 MB. Copyright © The Nobel ...
System for Magnetic Resonance Spectroscopy of Brain Tissue for Pattern-Based Diagnostics. * Share ... System for Magnetic Resonance Spectroscopy of Brain Tissue for Pattern-Based Diagnostics ... Available for licensing and commercial development is a system for preprocessing magnetic resonance spectroscopy (MRS) data of ... Computed Tomography and Magnetic Resonance Imaging (MRI) appearance have been used for early detection of cancer. However, by ...
Buy Cardiovascular Magnetic Resonance Spectroscopy by Saul Schaefer, Robert S. Balaban from Waterstones today! Click and ... Cardiovascular Magnetic Resonance Spectroscopy (Hardback). Saul Schaefer (editor), Robert S. Balaban (editor) Sign in to write ... The application of magnetic resonance spectroscopy (MRS) to the cardiovascular system is a relatively new phenomenon. Its ... realm of human myocardial metabolism has been made possible by the advent of relatively high-field magnets with spectroscopy ...
Phosphorus magnetic resonance spectroscopy monitors muscle energy metabolism by recording the ratio of phosphocreatine to ... Phosphorus magnetic resonance spectroscopy (31P MRS) in neuromuscular disorders Ann Neurol. 1991 Jul;30(1):90-7. doi: 10.1002/ ... Phosphorus magnetic resonance spectroscopy can also record intracellular pH and thus identify disorders of glycogen metabolism ... While phosphorus magnetic resonance spectroscopy remains primarily a research tool in metabolic myopathies, it will be ...
078 - Proton magnetic resonance spectroscopy in the brain (2002) Category: Reports AAPM Magnetic Resonance Task Group #9 on ... Some fundamental issues covered in this paper are common to many forms of magnetic resonance spectroscopy and are written as an ... Keywords: MRI, Proton Head Spectrocopy, SNR, Post-Processing, PPM Scale Magnetic Resonance Task Group #9 Dick J. Drost, William ... proton magnetic resonance spectroscopy (MRS) in the brain was formed to provide a reference document for acquiring and ...
Acquisition of mono- and bidimensional spectra of a wide variety of NMR active nuclei. Acquisition of spectra of solid samples using MAS (up to 30kHz). Determination of relaxation constants.
  • These properties are fundamentally the same as those used in the more familiar magnetic resonance imaging (MRI) , but the molecular applications use a somewhat different approach, appropriate to the change of scale from millimeters (of interest to radiologists) to nanometers (bonded atoms are typically a fraction of a nanometer apart), a factor of a million. (wikipedia.org)
  • Magnetic resonance spectroscopy is based on the same principles as magnetic resonance imaging (MRI), but goes a step further: it extracts metabolic information from the organ it's imaging. (cedars-sinai.edu)
  • Magnetic resonance spectroscopy (MRS) or spectroscopic imaging (MRSI) enables the detection of metabolites, amino acids, and lipids, among other biomolecules, in tumors of live mouse models of cancer. (springer.com)
  • Danishad KK, Sharma U, Sah RG, Seenu V, Parshad R, Jagannathan NR (2010) Assessment of therapeutic response of locally advanced breast cancer (LABC) patients undergoing neoadjuvant chemotherapy (NACT) monitored using sequential magnetic resonance spectroscopic imaging (MRSI). (springer.com)
  • Magnetic resonance imaging and spectroscopy for monitoring liver steatosis. (nih.gov)
  • Contemporary 1 H-magnetic resonance spectroscopy (MRS) techniques can estimate the levels of brain metabolites with a high reproducibility and add only 10 minutes to a routine or volumetric magnetic resonance imaging scan. (springer.com)
  • Magnetic resonance spectroscopy (MRS) is a companion technique to the more familiar magnetic resonance imaging (MRI) scan. (diabetesjournals.org)
  • Magnetic resonance imaging (MRI), which was invented at The University of Nottingham by Nobel laureate Sir Peter Mansfield, has had a major impact on medical science. (prospects.ac.uk)
  • Our current research focuses on the development and application of new techniques and hardware for MR imaging and spectroscopy (MRS), often via multidisciplinary collaboration. (prospects.ac.uk)
  • The purpose of this study is to evaluate normal volunteers and patients with a variety of diseases with magnetic resonance imaging. (bioportfolio.com)
  • Researchers will attempt different magnetic resonance imaging methods and techniques as well as different levels of magnetic strength. (bioportfolio.com)
  • Computed Tomography and Magnetic Resonance Imaging (MRI) appearance have been used for early detection of cancer. (fda.gov)
  • MRS is becoming a common adjunct to magnetic resonance imaging (MRI), especially for the differential diagnosis of tumors in the brain. (aapm.org)
  • Even though MR imaging is an offshoot of MR spectroscopy, clinical medical physicists familiar with MRI may not be familiar with many of the common practical issues regarding MRS. Numerous research labora- tories perform in vivo MRS on other magnetic nuclei, such as 31P, 13C, and 19F. (aapm.org)
  • Quantitative Assessment of Liver Fat with Magnetic Resonance Imaging and Spectroscopy. (nih.gov)
  • Using MR spectroscopy, a special form of MR imaging that allows researchers to analyze the chemical properties of tissue, Dr. Port and colleagues studied 60 to 70 regions of the brain at a time, gathering thousands of data points. (news-medical.net)
  • Following conventional cranial MR imaging, single voxel proton MR spectroscopy of the thalamus involving the VIM nuclei was performed bilaterally in both the patients with ET and controls. (biomedsearch.com)
  • Bruker is the market leader in magnetic resonance spectrocopy instruments including NMR, EPR and preclinical magnetic resonance imaging (MRI). (bruker.com)
  • Bruker is the market leader in magnetic resonance spectroscopy instruments including NMR, time-domain NMR , EPR and preclinical magnetic resonance imaging (MRI). (bruker.com)
  • An NMR is done on the same machine as an MRI (magnetic resonance imaging). (mainehealth.org)
  • Maine Medical Center's Neuroscience Institute in Portland offers magnetic resonance spectroscopy and other neurological imaging services. (mainehealth.org)
  • The objective of this study was to determine if any discrimination could bc achieved through use of nuclear magnetic resonance (NMR) spectroscopy or magnetic resonance imaging (MRI).of seeds. (usda.gov)
  • In vivo magnetic resonance spectroscopy (MRS) is a specialized technique associated with magnetic resonance imaging (MRI). (wikipedia.org)
  • Magnetic resonance spectroscopy is an analytical technique that can be used to complement the more common magnetic resonance imaging (MRI) in the characterization of tissue. (wikipedia.org)
  • Magnetic Resonance Spectroscopic Imaging (MRSI): a 2-dimensional (or 3-dimensional) MRS technique which uses two/three phase-encoding directions to create a two/three-dimensional map of spectra. (wikipedia.org)
  • Journal of Magnetic Resonance Imaging, 13, 560-567. (scirp.org)
  • Magnetic Resonance Imaging Clinics of North America, 6, 1-20. (scirp.org)
  • Both underwent a comprehensive neuropsychological evaluation and both were evaluated using the magnetic resonance imaging (MRI) and MRS at the University of Pennsylvania Medical Center. (aappublications.org)
  • Proton MR spectroscopy is an imaging tool that is highly sensitive for detecting cerebral injury. (ajnr.org)
  • To assess the role of proton magnetic resonance spectroscopy and dynamic contrast-enhanced magnetic resonance imaging in the differentiation between malignant and benign musculoskeletal tumors. (scielo.br)
  • The time-intensity curve and slope values using dynamic-enhanced perfusion magnetic resonance imaging in association with the presence of choline peak demonstrated by single voxel magnetic resonance spectroscopy study are useful in the differentiation between malignant and benign musculoskeletal tumors. (scielo.br)
  • Hyperpolarized 13C-Magnetic Resonance Spectroscopy: Are We Ready for Metabolic Imaging? (ovid.com)
  • Contrast enhanced computerized tomography (CECT) and magnetic resonance imaging (MRI) studies had shown the results more in favor of tuberculoma. (eduzhai.net)
  • All of the participants underwent magnetic resonance imaging (MRI) and non-selective (31)P MRS (3 T) of the leg muscles before and after graded exercise on a treadmill. (biomedsearch.com)
  • Seventeen schizophrenia patients and 17 healthy volunteers underwent proton magnetic resonance spectroscopy (MRS) and imaging to measure neurochemical and structural changes in vivo . (uwo.ca)
  • Imaging Neurodegeneration: What can Magnetic Resonance Spectroscopy Contribute? (wisepress.com)
  • 200 cal) on multi-organs of primary interest (liver, visceral/subcutaneous/bone marrow fat, muscle) using non-invasive advanced magnetic resonance spectroscopic (MRS) and imaging (MRI) methods. (frontiersin.org)
  • They state that the spectroscopy was performed on 4 patients with neurologic symptoms and a diagnosis of parenchymal mass lesions on MR imaging. (ajnr.org)
  • Progress in Nuclear Magnetic Resonance Spectroscopy publishes review papers describing research related to theory and application of NMR spectroscopy. (scimagojr.com)
  • The diagnostic utility of prostate cancer metabolites measured with proton magnetic resonance spectroscopy (1HMRS) has been tested. (aacrjournals.org)
  • Proton magnetic resonance spectroscopy (MRS) measures brain tissue metabolism in vivo and could facilitate a "probable CTE" diagnosis during life. (medscape.com)
  • Extension of these investigations into the realm of human myocardial metabolism has been made possible by the advent of relatively high-field magnets with spectroscopy capabilities and sufficient bore dimensions to allow human studies. (waterstones.com)
  • Phosphorus magnetic resonance spectroscopy monitors muscle energy metabolism by recording the ratio of phosphocreatine to inorganic phosphate at rest, during exercise, and during recovery from exercise. (nih.gov)
  • Phosphorus magnetic resonance spectroscopy can also record intracellular pH and thus identify disorders of glycogen metabolism in which the production of lactic acid is blocked during ischemic exercise. (nih.gov)
  • These results show that cellular metabolism can be recorded directly in intact cells by 31 P nuclear magnetic resonance. (pnas.org)
  • Magnetic resonance spectroscopy offers a broad range of noninvasive analytical methods for investigating metabolism in vivo. (diabetesjournals.org)
  • Because of its versatility, magnetic resonance spectroscopy (MRS) has emerged as a powerful modality for studying tissue-specific intracellular metabolism in vivo. (diabetesjournals.org)
  • In the current study, we used proton MR spectroscopy to evaluate cerebral metabolism and injury in children during DKA. (ajnr.org)
  • We aimed to elucidate the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats using in vivo magnetic resonance spectroscopy (MRS) and to determine their roles in the development of liver steatosis. (mdpi.com)
  • To specifically measure the contribution of astroglia to brain energy metabolism in humans, we used a novel noninvasive nuclear magnetic resonance spectroscopic approach. (jneurosci.org)
  • In this study, we used [2- 13 C]-labeled acetate to selectively measure the contribution of astroglial oxidative metabolism to total substrate oxidation and the rate of total glial/neuronal glutamate trafficking in human brain by 13 C NMR spectroscopy. (jneurosci.org)
  • 31P magnetic resonance spectroscopy (MRS) offers a unique non-invasive window on energy metabolism in skeletal muscle, with possibilities for longitudinal studies and of obtaining important bioenergetic data continuously and with sufficient time resolution during muscle exercise. (lu.se)
  • Available for licensing and commercial development is a system for preprocessing magnetic resonance spectroscopy (MRS) data of brain tissue for pattern-based diagnostics. (fda.gov)
  • Nuclear magnetic resonance spectroscopy , most commonly known as NMR spectroscopy or magnetic resonance spectroscopy ( MRS ), is a spectroscopic technique to observe local magnetic fields around atomic nuclei . (wikipedia.org)
  • In addition to conventionally detected ESR/EPR suitable for larger area "bulk" samples, we leverage several highly specialized electrically detected magnetic resonance (EDMR) schemes that allows detailed spectroscopic information to be obtained in fully-processed individual device structures. (nist.gov)
  • In many such applications it is desirable to provide a system that can produce a magnetic field having the required intensity, distribution and stability for high-resolution analytical spectroscopic applications. (google.com)
  • Finally, the clinical applications of cardiovascular MRS are addressed.Schaefer, Saul is the author of 'Cardiovascular Magnetic Resonance Spectroscopy' with ISBN 9780792316862 and ISBN 079231686X. (valorebooks.com)
  • The application of magnetic resonance spectroscopy (MRS) to the cardiovascular system is a relatively new phenomenon. (waterstones.com)
  • To compare noninvasive MRI and magnetic resonance spectroscopy (MRS) methods with liver biopsy to quantify liver fat content. (nih.gov)
  • Improving proton MR spectroscopy of brain tissue for noninvasive diagnostics. (fda.gov)
  • In the human brain, magnetic resonance spectroscopy (MRS) provides a noninvasive, risk-free method to monitor the biochemistry of acute and chronic stages of disease. (aappublications.org)
  • Although we commend the authors' enthusiasm for this technique, the paper lacks statistical significance and contains much bias to support the authors' claim that MR spectroscopy "can be helpful in the noninvasive diagnosis of acute demyelinating diseases" 1 when elevated glutamate/glutamine peaks are identified. (ajnr.org)
  • Proton magnetic resonance spectroscopy (MRS) may be one tool to support an in-life diagnosis of CTE. (medscape.com)
  • Nelson MT, Everson LI, Garwood M, Emory T, Bolan PJ (2008) MR spectroscopy in the diagnosis and treatment of breast cancer. (springer.com)
  • Comments on use of 1H MR spectroscopy for diagnosis of probable Alzheimer disease. (springer.com)
  • Correlation spectroscopy is a development of ordinary NMR. (wikipedia.org)
  • These include correlation spectroscopy (COSY) and total coherence transfer spectroscopy (TOCSY) to detect through-bond nuclear couplings, and nuclear Overhauser effect spectroscopy (NOESY) to detect couplings between nuclei that are close to each other in space. (wikipedia.org)
  • Protocols combining magnetic resonance perfusion, volumetry and spectroscopy in AD may prove to be powerful research tools. (springer.com)
  • The sample is placed in a magnetic field and the NMR signal is produced by excitation of the nuclei sample with radio waves into nuclear magnetic resonance , which is detected with sensitive radio receivers. (wikipedia.org)
  • The most common types of NMR are proton and carbon-13 NMR spectroscopy, but it is applicable to any kind of sample that contains nuclei possessing spin . (wikipedia.org)
  • The technique known as nuclear magnetic resonance (NMR) is based on the interaction of the magnetic properties of nuclei with the radio portion of the electromagnetic spectrum. (lycoming.edu)
  • Here a magnetic field is used to create energy levels for magnetic nuclei present in a molecule. (coursera.org)
  • Electrons on neighboring atoms will block, or "shield", the nuclei from some of the magnetic field. (jove.com)
  • A course dealing with the quantum and classical description of the nuclear magnetic resonance of an isolated system of two spin-1/2 nuclei. (wustl.edu)
  • When placed in a magnetic field, NMR active nuclei (such as 1H or 13C) absorb electromagnetic radiation at a frequency characteristic of the isotope. (wikipedia.org)
  • Several metabolically relevant nuclei, including hydrogen ( 1 H), carbon ( 13 C), and phosphorus ( 31 P), are magnetic resonance (MR)-visible, permitting the detection of a range of metabolites in a variety of tissues. (diabetesjournals.org)
  • The invention relates to a Nuclear Magnetic Resonance (NMR) spectroscopy device adapted for carrying out 1D and nD homo- and heteronuclear NMR spectroscopy measurements of a plurality of nuclei, comprising an RF coil adapted to transmit RF to and/or receive RF from a measuring volume, wherein the RF coil forms part of a non-tuned radiofrequency circuit. (patents.com)
  • The basic sensitivity of any particular nuclei is a function of the relative abundance (natural concentration of the NMR active isotope) and the magnetic moment. (spectroscopyeurope.com)
  • Most NMR facilities offer either liquid state NMR spectroscopy or solid state NMR spectroscopy and, rarely, time domain NMR. (edu.au)
  • PhysOrg.com) -- A new study using solid-state NMR spectroscopy to analyze intact bone paves the way for atomic-level explorations of how disease and aging affect bone. (phys.org)
  • We here present magic-angle spinning solid-state NMR spectroscopy (SSNMR) as a powerful method to investigate structures of macromolecular assemblies at atomic resolution. (jove.com)
  • Single voxel proton MR spectroscopy has been applied for characterizing the metabolic signatures of brain tumors for some time ( 24 - 32 ). (aacrjournals.org)
  • The examinations were performed in a 1.5 T magnetic resonance scanner with standard protocol, and single voxel proton magnetic resonance spectroscopy with 135 msec echo time. (scielo.br)
  • Single-voxel proton magnetic resonance spectroscopy was performed on all of them with an echo time of 30 milliseconds and a repetition time of 2500 milliseconds. (healthyplace.com)
  • Magnetic resonance spectros-copy: clinical applications and techniques. (springer.com)
  • After surgery, the freshly excised tumours were scanned on a clinical 3 T MRI scanner to derive lactate concentration within the whole tumour using double quantum filtered (DQF) magnetic resonance spectroscopy (MRS). Subsequently, histopathological analysis provided tumour grade, size, histological type, lactate dehydrogenase A and B (LDH-A and LDH-B), Ki-67 expression and Nottingham Prognostic Index (NPI). (nature.com)
  • Since drugs in clinical use are mostly natural or synthetic products, Nuclear Magnetic Resonance (NMR) spectroscopy is used to elucidation and confirmation of structures. (hubpages.com)
  • Magnetic resonance spectroscopy (MRS) is becoming more widely available for clinical applications and is able to provide information about the metabolic properties of regions of normal and abnormal tissue morphology. (aacrjournals.org)
  • Magnetic resonance spectroscopy (MRS) encompasses a variety of related techniques, such as nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR), that have a diverse array of research, clinical and industry applications. (bruker.com)
  • Clinical Proton MR Spectroscopy in Central Nervous system Disorders. (scirp.org)
  • Burtscher, I.M. and Holtas, S. (2001) Proton MR Spectroscopy in Clinical Routine. (scirp.org)
  • The reliability of spectroscopy is debatable and has to be decided on the merits along with clinical symptomatology. (eduzhai.net)
  • The thought of using MR spectroscopy in this situation is attractive because the current clinical approach may warrant a lumbar puncture and even biopsy. (ajnr.org)
  • Serkova NJ, Brown MS (2012) Quantitative analysis in magnetic resonance spectroscopy: from metabolic profiling to in vivo biomarkers. (springer.com)
  • Nuclear magnetic resonance spectroscopy of proteins (usually abbreviated protein NMR ) is a field of structural biology in which NMR spectroscopy is used to obtain information about the structure and dynamics of proteins , and also nucleic acids , and their complexes. (wikipedia.org)
  • However, in large molecules such as proteins the number of resonances can typically be several thousand and a one-dimensional spectrum inevitably has incidental overlaps. (wikipedia.org)
  • Nucleic acids also tend to have resonances distributed over a smaller range than proteins, making the spectra potentially more crowded and difficult to interpret. (wikipedia.org)
  • Highly affinic and reversible binding spinmarkers for analysing proteins with magnetic resonance spectroscopy, e.g. (innovations-report.com)
  • Frankfurt scientists have developed a novel orthogonal spin label for structural and functional analysis of proteins with electron paramagnetic resonance (EPR). (innovations-report.com)
  • Solution of the phase problem in the X-ray diffraction method for proteins with the nuclear magnetic resonance solution structure as initial model. (iucr.org)
  • Technical advances on high magnetic fields, methodological developments and sample preparation has established MAS SSNMR into a robust method to investigate insoluble proteins in various environments, notably in their biologically-relevant macromolecular assembled state or in cellular membranes, making the technique highly complementary to cryo-electron microscopy. (jove.com)
  • Nuclear Magnetic Resonance and Distortionless Enhancement by Polarization Transfer (DEPT) spectra help in obtaining the different numbers of carbons and protons attached to each. (hubpages.com)
  • synonymous with NMR = nuclear magnetic resonance) is a universal physical technique best known for non-invasive detection and anatomical mapping of water protons (H). MR-spectroscopy (MRS) records protons from tissue chemicals other than water, intrinsic phosphorus containing metabolites, sodium, potassium, carbon, nitrogen, and fluorine. (nih.gov)
  • In ethanol the methylene, hydroxyl, and methyl protons all have unique resonance frequencies. (jove.com)
  • For those unfamiliar with the technique, it is worth remembering that essentially only isotopes that contain an odd number of protons and/or neutrons have a magnetic moment and angular momentum to be detected by NMR spectroscopy. (spectroscopyeurope.com)
  • Nuclear magnetic resonance (NMR) is a unique tool for translational research, as in vitro results can be potentially translated into in vivo magnetic resonance protocols. (hindawi.com)
  • Besides STEAM and PRESS as the principal sequences used in in vivo magnetic resonance spectroscopy, there are adiabatic pulses. (wikipedia.org)
  • Nevertheless, they represent genuine candidates and should be considered for further in vivo magnetic resonance spectroscopy (MRS) studies. (uio.no)
  • Lactate concentration was quantified from freshly excised whole tumours with double quantum filtered (DQF) magnetic resonance spectroscopy (MRS), and Nottingham Prognostic Index (NPI), LDH-A and proliferative marker Ki-67 were assessed histologically. (nature.com)
  • Also, for some metastatic lesions and for high-grade gliomas, typically, there are resonances corresponding to lactate or lipids ( 26 , 27 ). (aacrjournals.org)
  • Reversal of brain metabolic alterations with zidovudine detected by proton localised magnetic resonance spectroscopy. (springer.com)
  • Brain proton magnetic resonance spectroscopy in HIV-related encephalopathy: identification of evolving metabolic patterns in relation to dementia and therapy. (springer.com)
  • Metabolic brain mapping in Alzheimer's disease using proton magnetic resonance spectroscopy. (springer.com)
  • While phosphorus magnetic resonance spectroscopy remains primarily a research tool in metabolic myopathies, it will be clinically useful in identifying new therapies and monitoring their effects in a variety of neuromuscular disorders. (nih.gov)
  • We are hopeful that very high-field MR spectroscopy will prove helpful by identifying metabolic markers of the disease. (news-medical.net)
  • In this study, the authors investigated the presence of biochemical or metabolic alterations in the thalamus of patients with ET using magnetic resonance (MR) spectroscopy. (biomedsearch.com)
  • Magnetic resonance spectroscopy (MRS), also known as nuclear magnetic resonance (NMR) spectroscopy, is a non-invasive, ionizing-radiation-free analytical technique that has been used to study metabolic changes in brain tumors, strokes, seizure disorders, Alzheimer's disease, depression, and other diseases affecting the brain. (wikipedia.org)
  • Zimmerman, R.A. and Wang, Z.J. (1997) The Value of Proton MR Spectroscopy in Pediatric Metabolic Brain Disease. (scirp.org)
  • The aim of this study was to evaluate the metabolic profiles of yak ( Bos grunniens ) serum, feces, and urine by using proton nuclear magnetic resonance ( 1 H-NMR), to serve as a reference guide for the healthy yak milieu. (mdpi.com)
  • AIM: To evaluate the effect of physical activity on the structural, morphological, and metabolic characteristics of the gastrocnemius muscle in familial Mediterranean fever (FMF) patients, utilizing quantitative (31)P magnetic resonance spectroscopy (MRS), in order to elucidate the mechanism of their exertional leg pain. (biomedsearch.com)
  • MR spectroscopy is a non-invasive in vivo method for measuring metabolite levels in various tissues based on the principles of nuclear magnetic resonance (NMR). (frontiersin.org)
  • At higher magnetic field strengths this can introduce significant bias in metabolite measurements. (bl.uk)
  • The presence or absence of imino proton resonances, or of coupling between 15 N atoms across a hydrogen bond, indicates the presence or absence of basepairing. (wikipedia.org)
  • Individual assignments of amide proton resonances in the proton NMR spectrum of the basic pancreatic trypsin inhibitor. (iucr.org)
  • Journal of Magnetic Resonance, 72, 502-508. (scirp.org)
  • ultra-broadband probe for NMR", Journal of Magnetic Resonance. (patents.com)
  • Most magnetic resonance (MR) techniques measure the signal fat-fraction (the fraction of the liver MR signal attributable to liver fat), which may be confounded by numerous technical and biological factors and may not reliably reflect fat content. (nih.gov)
  • Topics which are described in the present paper are the information content of the 31P magnetic resonance spectrum of skeletal muscle, some practical issues in the performance of this MRS methodology, related muscle biochemistry and the validity of. (lu.se)
  • Topics which are described in the present paper are the information content of the 31P magnetic resonance spectrum of skeletal muscle, some practical issues in the performance of this MRS methodology, related muscle biochemistry and the validity of interpreting results in terms of biochemical processes, the possibility of investigating reaction kinetics in vivo and some indications for fibre-type heterogeneity as seen in spectra obtained during exercise. (lu.se)
  • Bruker technology and knowledge that makes us the worldwide technology and market leader in electron paramagnetic resonance (EPR). (bruker.com)
  • Günther Laukien, founder of Bruker, dedicated his post-doctoral studies to NMR spectroscopy and, in 1958, published his pioneering paper on high-frequency NMR. (spectroscopyeurope.com)
  • 1 H-NMR spectroscopy is one of the main platforms for metabolomics because the very simple sample preparation and highly reproducible molecule quantification counterbalance a sensitivity lower than the one granted by other platforms such as mass spectrometry. (mdpi.com)
  • One way of in- creasing both the sensitivity and spectral resolution of MRS is to increase the static magnetic field strength. (bl.uk)
  • The main function of Nuclear Magnetic Resonance in pharmaceutical analysis is to elucidate and confirm the structures of substances that relate to drug (Kamienska-Trela, 2011). (hubpages.com)
  • To learn more about NMR spectroscopy in pharmaceutical analysis, or to speak with one of our experts, contact us today. (element.com)
  • We propose a nuclear-magnetic-resonance (NMR) experiment in which we titrate the chirality (enantiomeric excess) of a solvent and measure the diasteriomeric splitting in the spectra of a chiral solute in order to search for an anomalous offset due to parity nonconservation (PNC). (osti.gov)
  • To illustrate the method, comprehensive electron spin resonance spectra of a mesoscopic, single-crystal YIG disk at room temperature will be presented, along with situations where torque spectroscopy can offer complimentary information to existing magnetic resonance detection techniques. (spie.org)
  • Sequential resonance assignments in protein 1 H nuclear magnetic resonance spectra: computation of sterically allowed proton-proton distances and statistical analysis of proton-proton distances in single crystal protein conformations. (iucr.org)
  • We studied two patients with Creutzfeldt-Jakob disease by in vivo proton magnetic resonance spectroscopy and obtained spectra from an extract of biopsy tissue from a third patient. (neurology.org)
  • The potential for bias is evident if one examines the 2.1 to 2.5 region of the spectra where complex, unresolved resonances produce a "shoulder" of variable slope downfield from the N -acetylaspartate resonance. (ajnr.org)
  • Spectroscopy of the biopsy extract obtained 4 months after onset of symptoms showed no reduction in metabolites measured by in vivo spectroscopy, in accord with quantitative pathology showing no overall neuronal loss. (neurology.org)
  • Utilization of the inherent structural and quantitative information delivered via NMR spectroscopy can provide detailed mechanistic insights and increase process understanding. (news-medical.net)
  • Quantitative in vivo 31P magnetic resonance spectroscopy of Alzheimer disease. (harvard.edu)
  • This webinar will introduce a technique called 2D heteronuclear single quantum coherence (HSQC) NMR spectroscopy for assessing the quality control of a biologic. (news-medical.net)
  • The intramolecular magnetic field around an atom in a molecule changes the resonance frequency, thus giving access to details of the electronic structure of a molecule and its individual functional groups. (wikipedia.org)
  • Two-dimensional nuclear magnetic resonance (NMR) is indispensable to molecule structure determination. (nature.com)
  • Since instruments with different magnetic strengths will shift the resonant frequencies, they are referenced to a standard molecule added to the sample, often tetramethylsilane, or TMS. (jove.com)
  • Twenty-nine children with DKA underwent cerebral proton MR spectroscopy during DKA treatment (2-12 hours after initiating therapy) and after recovery from the episode (72 hours or more after the initiation of therapy). (ajnr.org)
  • Magnetic resonance, which exploits the change in energy levels after exposure to a strong magnetic field, forms the basis of some powerful analytical research tools. (bruker.com)
  • Brain ratios of N -acetylaspartate (NAA) to creatine (Cr), measured by proton MR spectroscopy, decrease with neuronal injury or dysfunction. (ajnr.org)
  • Proton magnetic resonance spectroscopy ( 1 H-MRS) of the central nervous system gives information on neuronal viability, cellular energy, and membrane status. (diabetesjournals.org)
  • Equipped for multinuclear analysis of solutions, for solid state analysis of organic solids, and for LC-NMR spectroscopy. (edu.au)
  • Equipped with a triple resonance helium cooled cryoprobe, broadband probe, 3.2 and 4mm solids probes, and 4mm HRMAS probe, automatic sample changer, and variable temperature capability. (unh.edu)
  • The sequential walking methodology is not possible for non-double helical nucleic acid structures, nor for the Z-DNA form, making assignment of resonances more difficult. (wikipedia.org)
  • The principle of NMR usually involves three sequential steps: The alignment (polarization) of the magnetic nuclear spins in an applied, constant magnetic field B0. (wikipedia.org)
  • Sequence-specific 1H resonance assignments were obtained using the sequential assignment method. (rcsb.org)
  • Among three vastly used techniques for structure analysis, X-ray, electron microscopy, and nuclear magnetic resonance (NMR), NMR is the most promising technique to reveal the structure information with nondestructive detection in the room temperature under living condition. (nature.com)
  • Introduction of Nuclear Magnetic Resonance Spectroscopy for polymorph detection in pharmaceuticals, over the past years, helps in the determination of the impurity profile of a drug. (hubpages.com)
  • The paper will look into the use of Nuclear Magnetic Resonance Spectroscopy for polymorph detection in pharmaceuticals. (hubpages.com)
  • The method relies on frequency mixing of orthogonal RF fields to yield a torque amplitude (arising from the transverse component of a precessing dipole moment, in analogy to magnetic resonance detection by electromagnetic induction) on a miniaturized resonant mechanical torsion sensor. (spie.org)
  • The purpose of this study is to assess the efficacy, of treating patients with recurrent glioblastoma using Gamma-Knife Radiosurgery (GKS) to target a tumor volume defined by a combination of gadolinium enhancement and magnetic resonance spectroscopy (MRS). This is a single center, Phase II trial. (clinicaltrials.gov)
  • Structure of human cyclophilin and its binding site for cyclosporin A determined by X-ray crystallography and NMR spectroscopy. (iucr.org)
  • Atomic insights into the assembly mechanisms and the functioning of those macromolecular assemblies remain often scarce since their inherent insolubility and non-crystallinity often drastically reduces the quality of the data obtained from most techniques used in structural biology, such as X-ray crystallography and solution Nuclear Magnetic Resonance (NMR). (jove.com)
  • Protein NMR utilizes multidimensional nuclear magnetic resonance experiments to obtain information about the protein. (wikipedia.org)
  • 1. A patient with familial adult-onset hypophosphataemia, whose myopathy was closely related to the plasma phosphate concentration, was investigated by phosphorus nuclear magnetic resonance spectroscopy ( 31 P n.m.r.) in vivo of the right flexor digitorum superficialis muscle. (clinsci.org)
  • We utilized solution phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy and an enzyme hydrolysis method to characterize P and assess bioavailability in 14 commonly mapped riparian soils from northwestern Vermont. (gc.ca)
  • There are also more complex 3D and 4D methods and a variety of methods designed to suppress or amplify particular types of resonances. (wikipedia.org)
  • Some fundamental issues covered in this paper are common to many forms of magnetic resonance spectroscopy and are written as an introduction for the reader to these methods. (aapm.org)
  • Magnets for magnetic resonance systems and methods for employing such systems in spectroscopy and biomedical applications are in general use. (google.com)
  • For example, a recent poll of methods utilised by pharma discovery scientists searching for the next new blockbuster drug highlights the dominance of NMR spectroscopy in fragment-based lead generation. (spectroscopyeurope.com)
  • Nuclear magnetic resonance (NMR) spectroscopy is a sophisticated and powerful yet non-destructive technique that employs strong magnetic fields and radiofrequencies to reveal the structural and dynamic characteristics of materials at the molecular level. (edu.au)
  • Designed for walk-up routine molecular structural analysis, via proton and multinuclear NMR spectroscopy, of organic compounds in solution. (edu.au)
  • NMR spectroscopy is at the center of most strategies for solving structural problems in all fields of chemistry. (lycoming.edu)
  • Herein, we present a protocol to perform high-resolution structural studies on insoluble and non-crystalline macromolecular protein assemblies by magic-angle spinning solid-state nuclear magnetic resonance spectroscopy (MAS SSNMR). (jove.com)
  • Advances in magic-angle spinning solid-state nuclear magnetic resonance spectroscopy (SSNMR) offer an efficient tool for the structural characterization of macromolecular protein assemblies at an atomic resolution. (jove.com)
  • 1 In this article, the authors reported the approach of examining glutamate/glutamine peaks in 1 H-MR (proton) spectroscopy to increase the specificity in differentiating tumefactive demyelinating processes from neoplasms. (ajnr.org)
  • we aim to examine whether a representative atypical antipsychotic, quetiapine, has different effects from conventional antipsychotics on the magnetic resonance spectroscopy (MRS) markers in schizophrenia patients. (clinicaltrials.gov)
  • In nuclear Overhauser effect (NOE) spectroscopy, the relaxation of the resonances is observed. (wikipedia.org)
  • Newman, R.H. and Hemmingson, J.A.. "Determination of the Degree of Cellulose Crystallinity in Wood by Carbon-13 Nuclear Magnetic Resonance Spectroscopy" , vol. 44, no. 5, 1990, pp. 351-356. (degruyter.com)
  • Ever since that experience, I have generally avoided the ordeal of locking horns with NMR experts and confined myself to the peaceful waters of familiar spin ½ carbon-13 and proton NMR spectroscopy. (spectroscopyeurope.com)
  • AAPM Magnetic Resonance Task Group #9 on proton magnetic resonance spectroscopy (MRS) in the brain was formed to provide a reference document for acquiring and processing proton (1H) MRS acquired from brain tissue. (aapm.org)
  • In this context, proton magnetic resonance spectroscopy ( 1 H-MRS) provides a non-invasive and widely available technique for investigating the biochemical milieu of brain tissue in vivo . (frontiersin.org)
  • Of course, the absolute concentration of carbon in the sample also plays a key role in the final signal-to-noise ratio of the measurement compared to proton NMR spectroscopy. (spectroscopyeurope.com)
  • An in vitro 1H nuclear magnetic resonance study of the temporoparietal cortex of Alzheimer brains. (springer.com)
  • N-acetyl-L-aspartate and other amino acid metabolites in Alzheimer's disease brain: a preliminary proton nuclear magnetic resonance study. (springer.com)
  • Brain N-acetyl-L-aspartic acid in Alzheimer's disease: a proton magnetic resonance spectroscopy study. (springer.com)
  • Nuclear Magnetic Resonance helps in the study drug contaminants and impurities including synthetic precursors, solvents, decomposition products and synthesis intermediates. (hubpages.com)
  • Magnetic resonance (MR) spectroscopy may prove to be the definitive diagnostic test for bipolar disorder, a serious brain illness characterized by an alternating pattern of extreme emotional highs and lows, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA) . (news-medical.net)
  • This is the first study to analyze drug-free bipolar patients using a 3T longbore MR scanner, which has twice the magnetic-field strength of scanners used in recent bipolar disorder studies. (news-medical.net)
  • The purpose of this study was to use proton magnetic resonance spectroscopy ( 1 H-MRS) to investigate whether neurochemical changes underlie abnormal brain function in BAFME. (dovepress.com)
  • This thesis describes several novel in-vivo proton magnetic resonance spectroscopy (MRS) techniques used to study the human brain. (bl.uk)
  • Why were these spectroscopy results not included in the study? (ajnr.org)
  • The facts in this study are not significant enough to suggest that MR spectroscopy "can be helpful" in distinguishing between tumefactive demyelinating diseases and neoplasm. (ajnr.org)
  • Untargeted metabolomics of lysate from cultured glioblastoma cells was carried out with liquid state proton nuclear magnetic resonance (NMR) spectroscopy at resonance frequency 800 MHz. (uio.no)