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2.
ACG Case Rep J ; 6(9): e00180, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31750370

RESUMO

We report a rare case of multiple esophageal squamous papillomas (ESPs). A 42-year-old man underwent a medical examination, and abnormalities of multiple elevated lesions were noted using a esophagogastroduodenoscope. He underwent upper gastrointestinal tract radiography with an orally ingested barium sulfate and gastrointestinal endoscopy, which revealed multiple elevated lesions in the esophagus, predominantly on the distal esophagus. We performed an endoscopic esophageal mucosal resection using a cap-fitted esophagogastroduodenoscope to obtain sufficient specimens. Based on the pathological findings, we diagnosed multiple ESPs. Although single ESPs or a few ESPs in a patient are often encountered, multiple ESP cases are rare.

3.
J Mol Biol ; 365(4): 903-10, 2007 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-17107688

RESUMO

UV exposure of DNA molecules induces serious DNA lesions. The cyclobutane pyrimidine dimer (CPD) photolyase repairs CPD-type - lesions by using the energy of visible light. Two chromophores for different roles have been found in this enzyme family; one catalyzes the CPD repair reaction and the other works as an antenna pigment that harvests photon energy. The catalytic cofactor of all known photolyases is FAD, whereas several light-harvesting cofactors are found. Currently, 5,10-methenyltetrahydrofolate (MTHF), 8-hydroxy-5-deaza-riboflavin (8-HDF) and FMN are the known light-harvesting cofactors, and some photolyases lack the chromophore. Three crystal structures of photolyases from Escherichia coli (Ec-photolyase), Anacystis nidulans (An-photolyase), and Thermus thermophilus (Tt-photolyase) have been determined; however, no archaeal photolyase structure is available. A similarity search of archaeal genomic data indicated the presence of a homologous gene, ST0889, on Sulfolobus tokodaii strain7. An enzymatic assay reveals that ST0889 encodes photolyase from S. tokodaii (St-photolyase). We have determined the crystal structure of the St-photolyase protein to confirm its structural features and to investigate the mechanism of the archaeal DNA repair system with light energy. The crystal structure of the St-photolyase is superimposed very well on the three known photolyases including the catalytic cofactor FAD. Surprisingly, another FAD molecule is found at the position of the light-harvesting cofactor. This second FAD molecule is well accommodated in the crystal structure, suggesting that FAD works as a novel light-harvesting cofactor of photolyase. In addition, two of the four CPD recognition residues in the crystal structure of An-photolyase are not found in St-photolyase, which might utilize a different mechanism to recognize the CPD from that of An-photolyase.


Assuntos
Desoxirribodipirimidina Fotoliase/química , Flavina-Adenina Dinucleotídeo/química , Complexos de Proteínas Captadores de Luz/química , Sulfolobus/enzimologia , Sequência de Aminoácidos , Catálise , Cristalografia por Raios X , Cianobactérias/enzimologia , DNA/química , Escherichia coli/enzimologia , Genoma Arqueal , Conformação Molecular , Dados de Sequência Molecular , Fases de Leitura Aberta , Estrutura Secundária de Proteína , Thermus thermophilus/enzimologia
5.
Bioinformatics ; 20(17): 3238-40, 2004 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-15059839

RESUMO

Timely worldwide distribution of biosequence and bioinformatics data depends on high performance networking and advances in Internet transport methods. The Bio-Mirror project focuses on providing up-to-date distribution of this rapidly growing and changing data. It offers FTP, Web and Rsync access to many high-volume databanks from several sites around the world. Experiments with data grids and other methods offer future improvements in biology data distribution.


Assuntos
Biologia Computacional/métodos , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Genéticas , Documentação/métodos , Disseminação de Informação/métodos , Armazenamento e Recuperação da Informação/métodos , Internet , Biologia/métodos , Redes de Comunicação de Computadores , Integração de Sistemas
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