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2.
Anal Sci ; 28(9): 837-44, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22975910

RESUMO

An effort is made to critically present the achievements in silver ion chromatography during the last decade. Novelties in columns, mobile-phase compositions and detectors are described. Recent applications of silver ion chromatography in the analysis of fatty acids and triacylglycerols are presented while stressing novel analytical strategies or new objects. The tendencies in the application of the method in complementary ways with reversed-phase chromatography, chiral chromatography and, especially, mass detection are outlined.


Assuntos
Ácidos Graxos/análise , Prata/química , Triglicerídeos/análise , Cromatografia Líquida de Alta Pressão/história , Cromatografia em Camada Fina/história , Ácidos Graxos/história , História do Século XXI , Íons/química , Íons/história , Prata/história , Extração em Fase Sólida/história , Triglicerídeos/história
4.
Br J Nutr ; 97(5): 809-13, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17408519

RESUMO

The coordinated regulation of metabolic fuel selection is crucial to energy homeostasis. Philip Randle and his colleagues developed the fundamental concept of interplay between carbohydrate and lipid fuels in relation to the requirement for energy utilisation and storage. Their insight has fashioned current understanding of the regulation of metabolism in health and disease, as well as providing a springboard for research into the roles of lipid derivatives in insulin resistance and, at the transcriptional level, lipid-regulated nuclear hormone receptors.


Assuntos
Ácidos Graxos/história , Glucose/história , Ácidos Graxos/metabolismo , Expressão Gênica , Glucose/metabolismo , História do Século XX , História do Século XXI , Insulina/história , Insulina/metabolismo , Resistência à Insulina , Metabolismo dos Lipídeos , Lipídeos/história , Redes e Vias Metabólicas
5.
Anal Bioanal Chem ; 387(3): 829-36, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16896625

RESUMO

The application of combined Raman spectroscopic and GC-MS analytical techniques for the characterisation of organic varnish residues from Egyptian Dynastic funerary sarcophagal and cartonnage fragments from the Graeco-Roman period, ca. 2200 BP, is described. The nondestructive use of Raman spectroscopy was initially employed to derive information about the specific location of organic material on the specimens, which were then targeted in specific areas using minimal sampling for GC-MS analysis. In the case of the sarcophagal fragment, a degraded yellow-brown surface treatment was identified as a Pistacia spp. resin; this provides additional evidence for the use of this resin, which has previously been identified in Canaanite transport amphorae, varnishes and "incense" bowls in an Egyptian Late Bronze Age archaeological context. The cartonnage fragment also contained an organic coating for which the Raman spectrum indicated a degradation that was too severe to facilitate identification, but the GC-MS data revealed that it was composed of a complex mixture of fatty acid residues. The combined use of GC-MS and Raman spectroscopy for the characterisation of organic materials in an archaeological context is advocated for minimisation of sampling and restriction to specifically identified targets for museum archival specimens.


Assuntos
Arqueologia/métodos , Ácidos Graxos/análise , Compostos Orgânicos/análise , Resinas Vegetais/análise , Antigo Egito , Ácidos Graxos/química , Ácidos Graxos/história , Cromatografia Gasosa-Espectrometria de Massas/métodos , História Antiga , Compostos Orgânicos/química , Compostos Orgânicos/história , Resinas Vegetais/química , Resinas Vegetais/história , Análise Espectral Raman/métodos
7.
Biophys Chem ; 100(1-3): 151-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12646361

RESUMO

After 1946, serum albumin was available for studies. Its residue sequence and internal disulfide bonding was developed by 1976. We began to make dielectric dispersion studies and apply Perrin's equations for rotational relaxation times around the two axes of revolution in 1938. These data indicated that albumin should have an elongated shape. In 1992 atomic structure data indicated the molecule was heart-shaped. A similar 1998 study of albumin complexed with fatty acid showed that the molecule was substantially rearranged. We found that the dielectric constant of albumin solutions was sensitive to fatty acid content, making this property an attractive probe in stop-flow kinetic studies. Such studies show that the fatty acid reaction is a two-step process. The fatty acid first binds to exterior sites in a diffusion-limited second order reaction complete in 1 ms. Then a first order rearrangement reaction with approximately 400 ms half-life follows. Thus the highly specialized serum albumin sequence of amino acid residues determines not only the structure of the unligated molecule, but also the distinctive structures of the numerous multiligated molecules.


Assuntos
Albumina Sérica/história , Animais , Bioquímica/história , Eletroquímica/história , Ácidos Graxos/história , Ácidos Graxos/metabolismo , História do Século XX , Humanos , Ligantes , Proteínas de Plantas/química , Proteínas de Plantas/história , Ligação Proteica , Conformação Proteica , Albumina Sérica/química , Estados Unidos
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