Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Diabetes Obes Metab ; 7(5): 579-85, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16050951

RESUMO

BACKGROUND: Insulin resistance has been proposed as an important risk factor in the development of atherosclerosis. AIM: To evaluate the association of insulin resistance and coronary atherosclerosis, we investigated the correlation between insulin sensitivity and the degree of coronary stenosis in patients with angina pectoris. METHODS: The study population consisted of 74 subjects with angina (54 men and 20 women) aged from 31 to 73 years. Coronary angiograms were evaluated by three semiquantitative scoring systems (vessel score, stenosis score and extent score) to estimate the extent of focal and diffuse coronary artery disease (CAD). Insulin sensitivity (K(ITT)) was determined by the insulin tolerance test. RESULTS: There were significant correlations existed between K(ITT) and all three coronary scores. Multivariate analysis revealed significant and independent correlations of all three coronary scores with K(ITT) (vessel score: beta = -0.349, p = 0.004; stenosis score: beta = -0.487, p < 0.001; extent score: beta = -0.481, p < 0.001), even in patients without diabetes mellitus (vessel score: beta = -0.387, p = 0.008; stenosis score: beta = -0.469, p < 0.001; extent score: beta = -0.559, p < 0.001). K(ITT) was significantly lower in patient with diffuse CAD than without diffuse CAD (2.13 +/- 0.66 vs. 2.57 +/- 0.79%/min, p < 0.05). However, K(ITT) was not different between patients with and without focal CAD. CONCLUSIONS: Insulin sensitivity has statistically significant and independent associations with the extent of coronary stenosis. These results suggest that insulin resistance may play a major role in the development of diffuse coronary artery stenosis.


Assuntos
Angina Pectoris/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Resistência à Insulina , Adulto , Idoso , Angina Pectoris/sangue , Angina Pectoris/diagnóstico por imagem , Antropometria , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/diagnóstico por imagem , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença
2.
Appl Microbiol Biotechnol ; 60(1-2): 134-8, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12382054

RESUMO

The 5' upstream region of the cellulose synthase operon ( bcs operon) has been isolated by cloning from Escherichia coli. A gene encoding YhjQ is located 1.0 kb upstream of the bcs operon in E. coli. The function of YhjQ remains unknown. Insertional inactivation of the yhjQ gene causes abnormal cell division, resulting in incomplete partition of the chromosome and filamentous cells of various sizes. These results suggest that the product of yhjQ may affect normal doubling and cellular morphology.


Assuntos
Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/fisiologia , Escherichia coli/fisiologia , Genes Bacterianos/fisiologia , Regiões Promotoras Genéticas/fisiologia , Ciclo Celular , Divisão Celular/fisiologia , Núcleo Celular , Cromossomos Bacterianos , Clonagem Molecular , Escherichia coli/genética , Genoma Bacteriano , Microscopia Eletrônica , Dados de Sequência Molecular , Mutagênese Insercional , Óperon , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Mapeamento por Restrição
3.
Appl Microbiol Biotechnol ; 57(1-2): 138-45, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11693911

RESUMO

The yellow-pigmented bacterial strain causing green spot rot and death of layer was isolated from Porphyra dentata. This strain has been identified as Pseudomonas sp., harboring agarase, xylanase, and protease activity, as well as carboxymethyl-cellulase (CMCase). Using genomic DNA from the Pseudomonas sp. SK38 digested with Sau3AI and ligated into pBluescript II KS+, we isolated a cel gene encoding a CMCase in Pseudomonas sp. SK38. A 4.5-kb fragment was subcloned into pKR400. The structure of the cel9A gene consists of an open reading frame of 1,521 bp starting with a GTG start codon and ending with a TAG stop codon. It thus encodes 506 amino acid residues of a protein with a calculated molecular weight of 52,636 daltons plus a signal peptide of 22 amino acids. The deduced amino acid sequence of the cel9A protein is similar to the same protein of Clostridium thermocellum. It contains, in particular, the two conserved regions of the glycoside hydrolase family 9. The apparent molecular mass of the Cel9A protein is 52 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme is most active at pH 6-7 and an optimal temperature of around 30 degrees C.


Assuntos
Proteínas de Bactérias , Celulase/genética , Genes Bacterianos , Pseudomonas/genética , Sequência de Aminoácidos , Celulase/química , Clonagem Molecular , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Filogenia , Homologia de Sequência de Aminoácidos , Temperatura
4.
Biochem Biophys Res Commun ; 287(2): 348-54, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-11554733

RESUMO

The gene encoding an intracellular isoamylase from the Pectobacterium chrysanthemi PY35 was cloned in Escherichia coli DH5alpha and sequenced. The isoamylase gene (amyX) had an open reading frame of 1974 bp encoding 657 amino acid residues with a calculated molecular weight of 74,151 Da. The molecular weight of the enzyme was also estimated to be 74 kDa by activity staining of a SDS-PA gel. Isoamylase from P. chrysanthemi PY35 had 59% pairwise amino acid identity with glycogen debranching enzyme from E. coli and contained the four regions conserved among all amylolytic enzymes. The isoamylase was optimally active at pH 7 and 40 degrees C. AmyX hydrolyzed alpha-1,6-glycosidic linkages of amylopectin, while did not hydrolyze alpha-1,4-glycosidic linkages of amylose.


Assuntos
Enterobacteriaceae/enzimologia , Isoamilase/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/análise , Enterobacteriaceae/genética , Isoamilase/metabolismo , Dados de Sequência Molecular
5.
Water Res ; 35(4): 937-42, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11235889

RESUMO

The removal of Cu(II) by a mesoporous material, FSM-16, was studied using electron paramagnetic resonance (EPR) spectroscopy and surface complexation modeling (SCM). Free copper ions, adsorbed and precipitated Cu(II) species were qualitatively identified by in situ EPR spectroscopy of Cu-FSM-16 suspensions at room temperature and at 77 K. In addition, the adsorbed species was identified as a Cu(II) species with an axial symmetry from an analysis of the EPR spectra of "dry" Cu-FSM-16 at 77 K. On the basis of the EPR results, the removal of Cu(II) as a function of pH under various experimental conditions was successfully simulated by assuming two removal mechanisms such as surface complexation and surface precipitation. In the acidic pH range (< pH 6), free copper ions were predominant, and surface complexed then surface precipitated species became dominant as the pH increased.


Assuntos
Cobre/isolamento & purificação , Silicatos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Precipitação Química , Espectroscopia de Ressonância de Spin Eletrônica , Concentração de Íons de Hidrogênio , Propriedades de Superfície
6.
Heart ; 85(1): E1, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11119479

RESUMO

Aneurysms of the left main coronary arteries are found in 0.1% of angiograms. This case involves an athlete with a left main coronary artery aneurysm, which was combined with chronic total occlusion of the proximal left anterior descending and proximal left circumflex coronary arteries. The extraordinary clinical presentation in this patient may be associated with good coronary collaterals, which may have developed in the patient in response to chronic total occlusion of the coronary artery by the aneurysm, and repeat myocardial hypoxia during high levels of performance as a soccer player.


Assuntos
Aneurisma Coronário/diagnóstico , Adulto , Angiografia Coronária , Ecocardiografia , Humanos , Masculino , Futebol , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção
7.
Biochem Biophys Res Commun ; 279(2): 420-6, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11118302

RESUMO

Aquifex aeolicus is the hyperthermophilic bacterium known, with growth-temperature maxima near 95 degrees C. The cel8Y gene, encoding a thermostable endoglucanase (Cel8Y) from Aquifex aeolicus VF5, was cloned into a vector for expression and expressed in Escherichia coli XL1-Blue. A clone of 1.7 kb fragment containing endoglucanase activity, designated pKYCY100, was sequenced and found to contain an ORF of 978 bp encoding a protein of 325 amino acid residues, with a calculated molecular mass of 38,831 Da. This endoglucanase was designated cel8Y gene. The endoglucanase has an 18-amino-acid signal peptide but not cellulose-binding domain. The endoglucanase of A. aeolicus VF5 had significant amino acid sequence similarities with endoglucanases from glycosyl hydrolase family 8. The predicted amino acid sequence of the Cel8Y protein was similar to that of CMCase of Cellulomonas uda, BcsC of Escherichia coli, CelY of Erwinia chrysanthemi, and CMCase of Acetobacter xylinum. The molecular mass of Cel8Y was calculated to be 36,750 Da, which is consistent with the value obtained from result of CMC-SDS-PAGE of the purified enzyme. Cel8Y was thermostable, exhibiting maximal activity at 80 degrees C and pH optima of 7.0 and with half-lives of 2 h at 100 degrees C, 4 h at 90 degrees C.


Assuntos
Bactérias/enzimologia , Celulase/química , Celulase/metabolismo , Sequência de Aminoácidos , Bactérias/genética , Sequência de Bases , Celulase/genética , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli , Genes Bacterianos , Temperatura Alta , Cinética , Dados de Sequência Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Termodinâmica
8.
J Hepatobiliary Pancreat Surg ; 5(3): 303-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9880779

RESUMO

In the Far East, hepatic resection is the definitive treatment for complicated intrahepatic stones (IHS). However, many investigators have reported that the associated intrahepatic biliary stricture is the main cause of treatment failure. A retrospective comparative study was undertaken to clarify the long-term efficacy of hepatic resection for treatment of IHS and to investigate the clinical significance of intrahepatic biliary stricture in treatment failure after hepatic resection performed in 44 patients with symptomatic IHS. The patients were divided into two study groups: group A, with intrahepatic biliary stricture (n = 28) and group B, without stricture (n = 16). Residual or recurrent stones, recurrence of intrahepatic biliary stricture, late cholangitis, and final outcomes were analyzed and compared statistically between the two groups. The patients were followed up for a median duration of 65 months after hepatectomy. The overall incidence of residual or recurrent stones was 36% and 11%, respectively, in groups A and B. The initial treatment failure rate was 50% in group A and 31% in group B. Intrahepatic biliary stricture recurred in 46% of patients in group A, while none of the group B patients had biliary stricture recurrence (P = 0.001). More than two-thirds of the restrictures in group A were identified at the primary site. The incidence of late cholangitis was higher in group A (54%) than in group B (6%) (P = 0. 002). Three-quarters of the patients with cholangitis in group A had severe cholangitis, that was recurrent, and related to stones and strictures (n = 11). They and 2 asymptomatic patients in group B required secondary procedures done at a median of 12 months after hepatectomy. Final outcomes after hepatectomy with or without secondary management were good in 80%, fair in 16%, and poor in 4% of our 44 patients. Most recurrent cholangitis after hepatectomy in patients with IHS was related to recurrent intrahepatic ductal strictures. Therefore, to be effective, hepatic resection should include the strictured duct. However, with hepatectomy alone it is difficult to clear the IHS or relieve the ductal strictures completely, particularly in patients with bilateral IHS, so perioperative team approaches that include both radiologic and cholangioscopic interventions should be combined for the effective management of IHS.


Assuntos
Ductos Biliares Intra-Hepáticos , Colelitíase/cirurgia , Colestase Intra-Hepática/complicações , Hepatectomia , Estudos de Casos e Controles , Colangite/etiologia , Colangite/cirurgia , Colelitíase/complicações , Colestase Intra-Hepática/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Falha de Tratamento
9.
Cancer ; 79(10): 1879-83, 1997 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9149012

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) is overexpressed in various malignancies including carcinoma of the breast, lung, esophagus, cervix, and stomach. In patients with gastric carcinoma, its overexpression may be associated with advanced stage and poor prognosis. METHODS: The levels of EGFR extracellular domain were determined in serum from 40 gastric carcinoma patients using enzyme-linked immunosorbent assay. Serum EGFR levels were measured in 5 Stage I, 2 Stage II, 6 Stage III, and 27 Stage IV patients, and 29 healthy controls. RESULTS: The mean serum level for EGFR in the gastric carcinoma patients was significantly elevated compared with that of healthy controls (681 +/- 226 fmol/mL vs. 440 +/- 46 fmol/mL; P < 0.0001). Thirty-one patients with gastric carcinoma (77.5%) showed elevated EGFR levels above a cutoff value of 532 fmol/mL (defined as 2 standard deviations above the mean of the controls). No significant association was noted between positivity of EGFR and gender, age, stage, and tumor differentiation. CONCLUSIONS: The authors believe that serum EGFR could be useful as a tumor marker of gastric carcinoma for diagnosis, prognosis, follow-up after surgery, and monitoring patient response to chemotherapy.


Assuntos
Carcinoma/sangue , Receptores ErbB/sangue , Neoplasias Gástricas/sangue , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma/patologia , Ensaio de Imunoadsorção Enzimática , Receptores ErbB/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Estadiamento de Neoplasias , Prognóstico , Fatores Sexuais , Neoplasias Gástricas/patologia
10.
Biotechnol Bioeng ; 25(1): 53-65, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18548538

RESUMO

A new type of reactor, an attrition bioreactor, was tested to achieve a higher rate and extent of enzymatic saccharification of cellulose than is possible with conventional methods. The reactor consisted of a jacketted stainless-steel vessel with shaft, stirrer, and milling media, which combined the effect of the mechanical action of wet milling with cellulose hydrolysis. The substrates tested were newsprint and white-pine heartwood. The performance of the reactor was excellent. The extent and rate of enzymatic hydrolysis could be markedly improved over other methods. The power consumption of the attrition bioreactor was also measured. The cellulase enzyme deactivation during attrition milling was not significant.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...