Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Br J Cancer ; 110(2): 271-7, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24281004

RESUMO

BACKGROUND: This randomised phase II trial compared dose-escalated weekly paclitaxel (wPTX) vs standard-dose wPTX for patients with previously treated advanced gastric cancer (AGC). METHODS: Ninety patients were randomised to a standard dose of wPTX (80 mg m(-2)) or an escalated dose of wPTX (80-120 mg m(-2)) to assess the superiority of overall survival (OS) with a one-sided alpha error of 0.3 and a power of 0.8. RESULTS: The median OS showed a trend towards longer survival in the dose-escalated arm (11.8 vs 9.6 months; hazard ratio (HR), 0.75; one-sided P=0.12), although it was statistically not significant. The median progression-free survival (PFS) was significantly longer in the dose-escalated arm (4.3 vs 2.5 months, HR, 0.55; P=0.017). Objective response rate was 30.3% with dose escalation and 17.1% with standard dose (P=0.2). The frequency of all grades of neutropenia was significantly higher with dose escalation (88.7% vs 60.0%, P=0.002); however, no significant difference was observed in the proportion of patients experiencing grade 3 or more (40.9% vs 31.1%, P=0.34). CONCLUSION: Dose-escalated wPTX in patients with pretreated AGC met our predefined threshold of primary end point, OS (P<0.3); however, it did not show a significantly longer OS. Progression-free survival was significantly better with dose escalation.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Paclitaxel/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Fitogênicos/efeitos adversos , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/efeitos adversos , Neoplasias Gástricas/mortalidade
2.
Nature ; 450(7169): 529-32, 2007 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-18033292

RESUMO

The effect of quantum statistics in quantum gases and liquids results in observable collective properties among many-particle systems. One prime example is Bose-Einstein condensation, whose onset in a quantum liquid leads to phenomena such as superfluidity and superconductivity. A Bose-Einstein condensate is generally defined as a macroscopic occupation of a single-particle quantum state, a phenomenon technically referred to as off-diagonal long-range order due to non-vanishing off-diagonal components of the single-particle density matrix. The wavefunction of the condensate is an order parameter whose phase is essential in characterizing the coherence and superfluid phenomena. The long-range spatial coherence leads to the existence of phase-locked multiple condensates in an array of superfluid helium, superconducting Josephson junctions or atomic Bose-Einstein condensates. Under certain circumstances, a quantum phase difference of pi is predicted to develop among weakly coupled Josephson junctions. Such a meta-stable pi-state was discovered in a weak link of superfluid 3He, which is characterized by a 'p-wave' order parameter. The possible existence of such a pi-state in weakly coupled atomic Bose-Einstein condensates has also been proposed, but remains undiscovered. Here we report the observation of spontaneous build-up of in-phase ('zero-state') and antiphase ('pi-state') 'superfluid' states in a solid-state system; an array of exciton-polariton condensates connected by weak periodic potential barriers within a semiconductor microcavity. These in-phase and antiphase states reflect the band structure of the one-dimensional polariton array and the dynamic characteristics of metastable exciton-polariton condensates.

3.
Br J Cancer ; 104(5): 856-62, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21285991

RESUMO

BACKGROUND: Activating mutation of KRAS and BRAF are focused on as potential prognostic and predictive biomarkers in patients with colorectal cancer (CRC) treated with anti-EGFR therapies. This study investigated the clinicopathological features and prognostic impact of KRAS/BRAF mutation in advanced and recurrent CRC patients. METHOD: Patients with advanced and recurrent CRC treated with systemic chemotherapy (n=229) were analysed for KRAS/BRAF genotypes by cycleave PCR. Prognostic factors associated with survival were identified by univariate and multivariate analyses using the Cox proportional hazards model. RESULTS: KRAS and BRAF mutations were present in 34.5% and 6.5% of patients, respectively. BRAF mutated tumours were more likely to develop on the right of the colon, and to be of the poorly differentiated adenocarcinoma or mucinous carcinoma, and peritoneal metastasis. The median overall survival (OS) for BRAF mutation-positive and KRAS 13 mutation-positive patients was 11.0 and 27.7 months, respectively, which was significantly worse than that for patients with wild-type (wt) KRAS and BRAF (40.6 months) (BRAF; HR=4.25, P<0.001, KRAS13; HR=2.03, P=0.024). After adjustment for significant features by multivariate Cox regression analysis, BRAF mutation was associated with poor OS (HR=4.23, P=0.019). CONCLUSION: Presence of mutated BRAF is one of the most powerful prognostic factors for advanced and recurrent CRC. The KRAS13 mutation showed a trend towards poor OS in patients with advanced and recurrent CRC.


Assuntos
Neoplasias Colorretais/genética , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Genes ras , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Recidiva
4.
J Phys Chem B ; 110(21): 10430-5, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16722749

RESUMO

Tungsten oxide (WO3) thin films have been produced by KrF excimer laser (lambda = 248 nm) ablation of bulk ceramic WO3 targets. The crystal structure, surface morphology, chemical composition, and structural stability of the WO3 thin films have been studied in detail. Characterization of freshly grown WO3 thin films has been performed using X-ray diffraction (XRD), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy (RS), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) measurements. The results indicate that the freshly grown WO3 thin films are nearly stoichiometric and well crystallized as monoclinic WO3. The surface morphology of the resulting WO3 thin film has grains of approximately 60 nm in size with a root-mean-square (rms) surface roughness of 10 nm. The phase transformations in the WO3 thin films were investigated by annealing in the TEM column at 30-500 degrees C. The phase transitions in the WO3 thin films occur in sequence as the temperature is increased: monoclinic --> orthorhombic --> hexagonal. Distortion and tilting of the WO6 octahedra occurs with the phase transitions and significantly affects the electronic properties and, hence, the electrochemical device applications of WO3.

5.
Eur J Radiol ; 20(2): 126-32, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7588867

RESUMO

To assess the accuracy of automatic extraction of the left ventricular inner contour on contrast-enhanced ultrafast cine magnetic resonance (MR) images, we compared the values obtained by this method with those obtained using intravenous digital subtraction left ventriculography. High-quality single breath-hold contrast-enhanced ultrafast cine MR images were obtained in all cardiac phases on horizontal and vertical long axis sections of the left ventricle. For ultrafast cine MR imaging, a phase-rewind gradient-echo (rewind-SMASH) sequence was used. Automatic extraction of the left ventricular inner contour on contrast-enhanced ultrafast cine MR images was performed in all cardiac phases. High-quality left ventricular images of the horizontal long axis section were obtained in 127 of 160 patients (79%). The automatic extraction of the left ventricular contour was easily performed on high-quality images with very short processing time (4 s/frame). The values for left ventricular volumes obtained with the automatic extraction method on contrast-enhanced ultrafast cine MR imaging were correlated well with those obtained with the manual extraction method and IV-DSA in high quality cardiac images. The biplane modified Simpson's method using automatic extraction is an accurate and highly reproducible method for evaluating left ventricular volumes.


Assuntos
Volume Cardíaco , Cardiopatias/diagnóstico , Cardiopatias/fisiopatologia , Ventrículos do Coração , Imageamento por Ressonância Magnética/métodos , Cardiopatias/diagnóstico por imagem , Humanos , Intensificação de Imagem Radiográfica , Volume Sistólico
6.
Nihon Rinsho ; 57(6): 1417-20, 1999 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-10391011

RESUMO

Recently a novel virus named TT virus (TTV), associated with posttransfusion hepatitis, was isolated. The prevalence of TTV infection and the route of TTV transmission in HD units was investigated. TTV was detected in 51.3% of patients on HD (59/115), as compared with 16.5% of healthy blood donors (15/91). The prevalence rate of TTV in the patients without history of blood transfusion was similarly high (51.6%), compared with that of those with history of blood transfusion (51.2%). The prevalence rate of TTV did not differ according to the duration of HD. These suggest that the risk of TTV infection is very high in HD units and there is another major route of TTV transmission than blood transfusion.


Assuntos
Infecções por Vírus de DNA/epidemiologia , Vírus de DNA/isolamento & purificação , Hepatite C/epidemiologia , Hepatite Viral Humana/epidemiologia , Diálise Renal/efeitos adversos , Biomarcadores/análise , Infecções por Vírus de DNA/transmissão , Infecções por Vírus de DNA/virologia , DNA Viral/análise , Hepatite C/virologia , Hepatite Viral Humana/transmissão , Hepatite Viral Humana/virologia , Humanos , Japão/epidemiologia , Prevalência , RNA Viral/análise
9.
Am J Gastroenterol ; 94(12): 3567-70, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10606320

RESUMO

OBJECTIVE: Recently, TT virus (TTV), associated with posttransfusion hepatitis, was discovered. Prevalence of TTV infection in maintenance hemodialysis (HD) units and its pathogenicity to liver was investigated. METHODS: A total of 115 patients on HD were assessed for presence of serum TTV. DNA was purified from sera, and nested polymerase chain reaction was done for the detection of TTV DNA. RESULTS: TTV was detected in 59 patients on HD (51.3%), as compared with healthy blood donors (15 of 91 [16.5%], p < 0.0001). Serum HCV RNA and HBs antigen were positive in 16 and three patients, respectively. The prevalence rate of TTV was already 58.3% in the patients on HD for only 1 yr, and did not change according to the duration of HD until 15 yr on HD. TTV was positive in 51.2% (43 of 84) of the patients with history of blood transfusion, and in 51.6% (16 of 31) of those without it. In HCV-negative patients, alanine aminotransferase (ALT) levels of TTV-positive patients were similar to those of TTV-negative patients. Contrarily, in HCV-positive patients, ALT levels were more frequently > or =15 IU/L in TTV-positive patients (14 of 18) than in TTV-negative patients (five of 15) (p < 0.05). CONCLUSIONS: TTV infection is remarkably prevalent in patients on HD and in healthy blood donors. It is suggested that TTV generally does not cause liver disease by itself, but there remains the possibility that TTV may aggravate liver disease caused by HCV.


Assuntos
Vírus de Hepatite/patogenicidade , Hepatite Viral Humana/transmissão , Diálise Renal , Idoso , Doadores de Sangue/estatística & dados numéricos , Estudos Transversais , Feminino , Hepacivirus/isolamento & purificação , Hepatite B/epidemiologia , Hepatite B/transmissão , Hepatite B/virologia , Vírus da Hepatite B/isolamento & purificação , Hepatite C/epidemiologia , Hepatite C/transmissão , Hepatite C/virologia , Hepatite Viral Humana/epidemiologia , Hepatite Viral Humana/virologia , Humanos , Incidência , Japão/epidemiologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Virulência
10.
Virology ; 264(1): 153-8, 1999 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-10544140

RESUMO

Hypervariable region 1 (HVR1) proteins of hepatitis C virus (HCV) have been reported to react broadly with sera of patients with HCV infection. However, the variability of the broad reactivity of individual HVR1 proteins has not been elucidated. We assessed the reactivity of 25 different HVR1 proteins (genotype 1b) with sera of 81 patients with HCV infection (genotype 1b) by Western blot. HVR1 proteins reacted with 2-60 sera. The number of sera reactive with each HVR1 protein significantly correlated with the number of amino acid residues identical to the consensus sequence defined by Puntoriero et al. (G. Puntoriero, A. Lahm, S. Zucchelli, B. B. Ercole, R. Tafi, M. Penzzanera, M. U. Mondelli, R. Cortese, A. Tramontano, G. Galfre', and A. Nicosia. 1998. EMBO J. 17, 3521-3533. ) (r = 0.561, P < 0.005). The most widely reactive HVR1 protein, 12-22, had a sequence similar to the consensus sequence. The peptide with C-terminal 13-amino-acids sequence of HVR1 protein 12-22 (NH2-CSFTSLFTPGPSQK) was injected into rabbits as an immunogen. The rabbit immune sera reacted with 9 of 25 HVR1 proteins of genotype 1b including HVR1 protein 12-22 and with 3 of 12 proteins of genotype 2a. These results indicate that the HVR1 protein broadly reactive with patients' sera has a sequence similar to the consensus sequence, can induce broadly reactive sera, and could be one of the candidate immunogens in a prophylactic vaccine against HCV.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Antígenos da Hepatite C/imunologia , Hepatite C Crônica/imunologia , Proteínas Virais/imunologia , Sequência de Aminoácidos , Animais , Sequência Consenso , Genótipo , Hepacivirus/genética , Hepatite C Crônica/sangue , Humanos , Imunoglobulina G/sangue , Dados de Sequência Molecular , Coelhos , Proteínas Recombinantes de Fusão/imunologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteínas Virais/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA