Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Catheter Cardiovasc Interv ; 91(2): 322-329, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28303634

RESUMO

OBJECTIVES: This report demonstrates the application and feasibility of novel 3D-MDCT real-time fusion technology with fluoroscopy, for left atrial appendage (LAA) occlusion procedures. BACKGROUND: A successful LAA occlusion procedure relies on multiple imaging modalities, including TEE or 3D-MDCT, and fluoroscopy. Effectively integrating these imaging modalities may improve implantation safety and success. To our knowledge this technique has not been previously described for LAA occlusions. METHODS: This observational study compared clinical and procedural parameters for procedures performed with or without fusion integration. All patients had a pre-procedural 3D-MDCT for LAA measurements, along with 3D analyses of LAA morphology and surrounding structures. Using the image fusion software (Valve ASSIST 2, GE Healthcare, UK), landmarks were identified on fluoroscopy, and MDCT LAA anatomy outlines were then projected onto the real-time fluoroscopy image during the procedure, to guide all steps of the intervention. RESULTS: A total of 57 patients underwent LAA occlusion, with 16 performed using fusion software. In comparison to the pre-fusion group, reductions in contrast volume (21.0 ± 11.7 vs. 95.9 ± 80.5 ml, P < 0.001), procedure time (63.0 ± 22.0 vs. 87.3 ± 43.0 min, P = 0.01), and fluoroscopy time (6.2 vs. 8.3 min, P = 0.03) were observed. Incomplete sealing (0 vs. 14.6%, P = 0.16) and device deployment success (100 vs. 92.7%, P = 0.17) were not significantly different. CONCLUSIONS: The addition of this novel fusion technology is safe and feasible. To optimize LAA procedural success, fusion integration may offer a promising addition, or alternative, to current imaging modalities. © 2017 Wiley Periodicals, Inc.


Assuntos
Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/terapia , Cateterismo Cardíaco , Imageamento Tridimensional/métodos , Tomografia Computadorizada Multidetectores/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Intervencionista/métodos , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Apêndice Atrial/fisiopatologia , Fibrilação Atrial/fisiopatologia , Cateterismo Cardíaco/instrumentação , Estudos de Viabilidade , Feminino , Fluoroscopia , Humanos , Masculino , Imagem Multimodal , Valor Preditivo dos Testes , Estudos Retrospectivos , Resultado do Tratamento
2.
Mol Psychiatry ; 22(12): 1701-1713, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27646262

RESUMO

Stressful life events produce a state of vulnerability to depression in some individuals. The mechanisms that contribute to vulnerability to depression remain poorly understood. A rat model of intense stress (social defeat (SD), first hit) produced vulnerability to depression in 40% of animals. Only vulnerable animals developed a depression-like phenotype after a second stressful hit (chronic mild stress). We found that this vulnerability to depression resulted from a persistent state of oxidative stress, which was reversed by treatment with antioxidants. This persistent state of oxidative stress was due to low brain-derived neurotrophic factor (BDNF) levels, which characterized the vulnerable animals. We found that BDNF constitutively controlled the nuclear translocation of the master redox-sensitive transcription factor Nrf2, which activates antioxidant defenses. Low BDNF levels in vulnerable animals prevented Nrf2 translocation and consequently prevented the activation of detoxifying/antioxidant enzymes, ultimately resulting in the generation of sustained oxidative stress. Activating Nrf2 translocation restored redox homeostasis and reversed vulnerability to depression. This mechanism was confirmed in Nrf2-null mice. The mice displayed high levels of oxidative stress and were inherently vulnerable to depression, but this phenotype was reversed by treatment with antioxidants. Our data reveal a novel role for BDNF in controlling redox homeostasis and provide a mechanistic explanation for post-stress vulnerability to depression while suggesting ways to reverse it. Because numerous enzymatic reactions produce reactive oxygen species that must then be cleared, the finding that BDNF controls endogenous redox homeostasis opens new avenues for investigation.


Assuntos
Transtorno Depressivo/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Antioxidantes/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Dominação-Subordinação , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Proteoma , Distribuição Aleatória , Ratos Sprague-Dawley
5.
Ann Pharm Fr ; 63(1): 53-62, 2005 Jan.
Artigo em Francês | MEDLINE | ID: mdl-15803101

RESUMO

Three glucuronyl prodrugs of paclitaxel have been synthesized in order to be activated by the B-glucuronidase present within the necrotic areas of tumors. As three compartments containing prodrugs, they include a specifier, a self immolative spacer and the drug. In vitro testing clearly indicates that the two former prodrugs are stable and are more or less detoxified. As expected, in the presence of E. coli B-glucuronidase, the glycosidic linkage is hydrolyzed with a rate depending on the nature of the spacer but, once this hydrolysis has occurred, the self immolative spacer is soon eliminated leading to the liberation of the paclitaxel.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias/tratamento farmacológico , Paclitaxel/análogos & derivados , Paclitaxel/farmacologia , Pró-Fármacos , Animais , Antineoplásicos Fitogênicos/síntese química , Biotransformação , Humanos , Neoplasias/metabolismo , Paclitaxel/síntese química
7.
J Chromatogr A ; 909(2): 111-35, 2001 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-11269513

RESUMO

The quality of sample preparation is a key factor in determining the success of analysis. While analysis of pharmaceutically important compounds in biological matrixes has driven forward the development of sample clean-up procedures in last 20 years, today's chemists face an additional challenge: sample preparation and analysis of complex biochemical samples for characterization of genotypic or phenotypic information contained in DNA and proteins. This review focuses on various sample pretreatment methods designed to meet the requirements for the analysis of biopolymers and small drugs in complex matrices. We discuss the advances in development of solid-phase extraction (SPE) sorbents, on-line SPE, membrane-based sample preparation, and sample clean-up of biopolymers prior to their analysis by mass spectrometry.


Assuntos
Cromatografia/métodos , Espectrometria de Massas/métodos , DNA/isolamento & purificação , Eletroquímica , Peptídeos/isolamento & purificação , Proteínas/isolamento & purificação
8.
Arch Mal Coeur Vaiss ; 94(12): 1409-12, 2001 Dec.
Artigo em Francês | MEDLINE | ID: mdl-11828927

RESUMO

Ruptures of sinus of Valsalva aneurysms are a rare complication, and very few cases of rupture in the left atrium have been described. In this clinical case we report the case of a patient hospitalised with a scenario of cardiac insufficiency revealing a very large posterior sinus of Valsalva aneurysm, associated with a bicuspid aortic valve, and rupture in the left atrium. The diagnosis was by transthoracic and transoesophageal multiplan echocardiography, and the treatment surgical, with a good result.


Assuntos
Aneurisma Aórtico/patologia , Ruptura Aórtica/patologia , Seio Aórtico/patologia , Idoso , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/cirurgia , Ruptura Aórtica/diagnóstico por imagem , Ruptura Aórtica/cirurgia , Ecocardiografia/métodos , Átrios do Coração , Insuficiência Cardíaca/complicações , Humanos , Masculino , Seio Aórtico/diagnóstico por imagem , Seio Aórtico/cirurgia , Resultado do Tratamento
9.
Anal Chem ; 72(7): 1469-74, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10763242

RESUMO

A 1-mm microbore hydrophilic interaction column has been used for the separation of 2-aminoacridone (2-AMAC)-derivatized glycan mixtures, released from naturally occurring and recombinant proteins. Primary structure identification of the 2-AMAC glycan derivatives was carried out by HPLC using fluorescence and mass spectrometric detection. In some cases, enzymatic digestion of the 2-AMAC glycans was applied to confirm glycan structure. This strategy is considerably more rapid than methods normally used in glycan analysis, which involves manual collection of separated oligosaccharide derivatives and analysis of individual fractions by mass spectrometry.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Oligossacarídeos/análise , Sequência de Carboidratos , Espectrometria de Massas , Dados de Sequência Molecular , Espectrometria de Fluorescência
10.
Am J Forensic Med Pathol ; 17(3): 207-10, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8870870

RESUMO

Coroner is an ancient office, dating back centuries in England; originally financial officers, coroners over time become medicolegal investigators. Coroners in early Massachusetts functioned under English common law and, later, under statute. However, studies of early coroners and inquests are not common, and many details of how coroners actually functioned are unknown. A previously unpublished set of 19th-century Massachusetts inquest records discloses details of coroner function, including administrative and financial details, social conditions surrounding inquests, and increasing use of medical and toxicologic testimony.


Assuntos
Médicos Legistas/história , Medicina Legal/história , Autopsia/legislação & jurisprudência , Médicos Legistas/legislação & jurisprudência , Prova Pericial , Feminino , História do Século XIX , Humanos , Masculino , Massachusetts , Toxicologia/legislação & jurisprudência
11.
Eur J Gastroenterol Hepatol ; 8(3): 267-71, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8724029

RESUMO

Viral chronic hepatitis often occurs in heart transplant recipients receiving cyclosporin. This essential immunosuppressive drug may induce cholestasis. We investigated the effect of treatment with cyclosporin on serum conjugated bile acids in patients with chronic hepatitis developing after heart transplantation. Fifty-nine patients were studied: 17 with chronic hepatitis, 15 heart transplant patients with normal alanine aminotransferase activity, and 27 heart transplant patients with chronic hepatitis, the last two groups receiving cyclosporin. Hepatic biochemical tests and total bile acid concentration were determined on fasting blood samples. The individual glyco- and tauroconjugated bile acids were quantified by high-performance liquid chromatography and direct spectrometry. In patients taking cyclosporin the bilirubin concentration and the alkaline phosphatase activity were increased only when hepatitis was present, in association with a slight increase in cholic acid level (5.13 microM vs. 0.68 microM; P < 0.01). Conjugated lithocholate concentration was dramatically higher when hepatitis and immunosuppression with cyclosporin were associated (1.17 microM vs. 0.03 and 0.04 microM; P < 0.01). Chenodeoxycholate was the main circulating bile acid only in the heart transplant patients treated with cyclosporin but without hepatitis. These results suggest that the mechanisms which explain the cyclosporin-associated modifications of the bile acid pool are different according to the presence or absence of hepatitis. The occurrence of hepatitis in patients on cyclosporin led to an increase in serum lithocholate and primary bile acid concentrations. Further studies are required to assess the effect of ursodeoxycholic acid for this cholestasis.


Assuntos
Colestase/induzido quimicamente , Ciclosporina/efeitos adversos , Transplante de Coração , Hepatite Crônica/complicações , Imunossupressores/efeitos adversos , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Ácidos e Sais Biliares/sangue , Bilirrubina/sangue , Ácido Quenodesoxicólico/sangue , Colestase/sangue , Ácido Cólico , Ácidos Cólicos/sangue , Cromatografia Líquida de Alta Pressão , Jejum , Feminino , Ácido Glicocólico/sangue , Hepatite Crônica/sangue , Humanos , Ácido Litocólico/sangue , Masculino , Pessoa de Meia-Idade , Espectrofotometria Ultravioleta , Ácido Taurocólico/sangue , Ácido Ursodesoxicólico/sangue
12.
J Chromatogr ; 330(2): 181-92, 1985 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-4066822

RESUMO

The retention behavior of methoxy-substituted p-benzoquinones and the corresponding hydroquinones in reversed-phase chromatography was examined on octylsilica and two octadecylsilica stationary phases and with five hydroorganic mobile phases containing acetonitrile, methanol or tetrahydrofuran and additionally in most cases (NH3OH)3PO4 used as a reducing and buffering agent. The retention order of benzoquinones and hydroquinones was the same on each stationary phase with either methanol or acetonitrile as the organic modifier. On the other hand, minor differences in the retention order were observed with the various stationary phases. In all cases, satisfactory quantitative structure-retention relationships (QSRRs) were found and the data suggest that the differences in the retention behaviour of octadecylsilicas used in this study are silanophilic interactions which, together with solvophobic interaction contribute to the retention of these eluites. Further analysis showed that QSRRs of sterically crowded molecules must take into account reduced surface area available for binding. The retention data obtained with use of aqueous tetrahydrofuran as mobile phase failed to give rise to satisfactory QSRRs. This was attributed to selective solvation of eluite by tetrahydrofuran and/or nearly equipotent binding of eluite and tetrahydrofuran to stationary phase.


Assuntos
Benzoquinonas , Hidroquinonas/análise , Quinonas/análise , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Octanóis , Solubilidade , Relação Estrutura-Atividade , Água
15.
Circulation ; 61(3): 648-52, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7353256

RESUMO

Three cases are presented showing retrograde alternate Wenckebach periods. Retrograde alternate Wenckebach periods were defined as 2:1 ventriculoatrial (VA) block in which the conducted beats showed progressive prolongation of conduction (VA) time. The sequence terminates with two or three successively blocked ventricular beats. In one of the three cases the level of block was identified as being in the atrioventricular (AV) node. In the other two the level of block could not be clearly identified. This report provides further evidence for the concept of multilevel block within the AV node. Retrograde alternate Wenckebach periods may explain some instances of variation of atrial depolarization intervals during episodes of ventricular tachycardia and may be clinically significant.


Assuntos
Nó Atrioventricular/fisiopatologia , Bloqueio Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Idoso , Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial , Eletrocardiografia , Aneurisma Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Síndrome do Nó Sinusal/fisiopatologia , Taquicardia/fisiopatologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA