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2.
Curr Oncol ; 21(2): 84-90, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24764697

RESUMO

BACKGROUND: Prediction of prognosis is important for patients so that they can make the most of the rest of their lives. Oncologists could predict survival, but the accuracy of such predictions is unclear. METHODS: In this observational prospective cohort study, 14 oncologists treating 9 major adult solid malignancies were asked to complete questionnaires predicting survival based on performance status, oral intake, and other clinical factors when patients experienced progressive disease after standard chemotherapies. Clinically predicted survival (cps) was calculated by the oncologists from the date of progressive disease to the predicted date of death. Actual survival (as) was compared with cps using Kaplan-Meier survival curves, and factors affecting inaccurate prediction were determined by logistic regression analysis. The prediction of survival time was considered accurate when the cps/as ratio was between 0.67 and 1.33. RESULTS: The study cohort consisted of 75 patients. Median cps was 120 days (interquartile range: 60-180 days), and median as was 121 days (interquartile range: 40-234 days). The participating oncologists accurately predicted as within a 33% range 36% of the time; the survival time was overestimated 36% of time and underestimated 28% of the time. The factors affecting the accuracy of the survival estimate were the experience of the oncologist, patient age, and information given about the palliative care unit. CONCLUSIONS: Prediction of cps was accurate for just slightly more than one third of all patients in this study. Additional investigation of putative prognostic factors with a larger sample size is warranted.

3.
Phys Rev Lett ; 107(14): 146801, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-22107226

RESUMO

A crucial requirement for quantum-information processing is the realization of multiple-qubit quantum gates. Here, we demonstrate an electron spin-based all-electrical two-qubit gate consisting of single-spin rotations and interdot spin exchange in a double quantum dot. A partially entangled output state is obtained by the application of the two-qubit gate to an initial, uncorrelated state. We find that the degree of entanglement is controllable by the exchange operation time. The approach represents a key step towards the realization of universal multiple-qubit gates.

4.
Phys Rev Lett ; 105(15): 156601, 2010 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-21230921

RESUMO

We report on the inversion of spin-dependent photocurrent via interface localized states formed at the interface of an Fe/n-AlGaAs/GaAs quantum well heterostructure by means of an optical spin orientation technique. A careful adjustment of the excitation photon energy, which is determined by a separate analysis of electroluminescence spectra under a spin injection condition, enables us to explore the spin-dependent characteristics of photoelectron transmission from the quantum well into Fe. The bias dependence of the spin-dependent photocurrent shows clear spikelike features at the voltage which is compatible with the formation of the interface localized resonant states in the Schottky depletion layer.

5.
Phys Rev Lett ; 102(23): 236806, 2009 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-19658960

RESUMO

We experimentally study the transport features of electrons in a spin-diode structure consisting of a single semiconductor quantum dot (QD) weakly coupled to one nonmagnetic and one ferromagnetic (FM) lead, in which the QD has an artificial atomic nature. A Coulomb stability diamond shows asymmetric features with respect to the polarity of the bias voltage. For the regime of two-electron tunneling, we find anomalous suppression of the current for both forward and reverse bias. We discuss possible mechanisms of the anomalous current suppression in terms of spin blockade via the QD-FM interface at the ground state of a two-electron QD.

6.
Phys Rev Lett ; 102(13): 137204, 2009 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-19392400

RESUMO

For the study of ferromagnetic materials which are compatible with group-IV semiconductor spintronics, we demonstrate control of the ferromagnetic properties of Heusler-alloy Fe3-xMnxSi epitaxially grown on Ge(111) by tuning the Mn composition x. Interestingly, we obtain L2(1)-ordered structures even for nonstoichiometric atomic compositions. The Curie temperature of the epilayers with x approximately 0.6 exceeds 300 K. Theoretical calculations indicate that the electronic structures of the nonstoichiometric Fe3-xMnxSi alloys become half-metallic for 0.75 < or = x < or = 1.5. We discuss the possibility of room-temperature ferromagnetic Fe(3-x)Mn(x)Si/Ge epilayers with high spin polarization.

7.
Tuberculosis (Edinb) ; 89(1): 62-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19028143

RESUMO

We have reported previously that recombinant BCG Tokyo (Ag85A) (rBCG-Ag85A[Tokyo]) shows promise as a tuberculosis vaccine, demonstrating protective efficacy in cynomolgus monkeys. As a next step, rhesus monkeys were utilized because they are also susceptible to Mycobacterium tuberculosis and show a continuous course of infection resembling human tuberculosis. The recombinant BCG vaccine (5x10(5) CFU per monkey) was administered once intradermally into the back skin to three groups of rhesus monkeys, and its protective efficacy was compared for 4months with that of its parental BCG Tokyo strain. Eight week vaccination of the monkeys with rBCG-Ag85A[Tokyo] resulted in a reduction of tubercle bacilli CFU (p<0.01) and lung pathology in animals infected intratracheally with 3000 CFU H37Rv M. tuberculosis. Vaccination prevented an increase in the old tuberculin test after challenge with M. tuberculosis and reaction of M. tuberculosis-derived antigen. Thus, it was shown that even in rhesus monkeys rBCG-Ag85A[Tokyo] induced higher protective efficacy than BCG Tokyo.


Assuntos
Aciltransferases/imunologia , Antígenos de Bactérias/imunologia , Vacina BCG/administração & dosagem , Tuberculose Pulmonar/prevenção & controle , Aciltransferases/genética , Animais , Antígenos de Bactérias/genética , Vacina BCG/genética , Humanos , Hidrolases , Pulmão/diagnóstico por imagem , Pulmão/imunologia , Macaca mulatta , Masculino , Modelos Animais , Radiografia , Baço/diagnóstico por imagem , Baço/imunologia , Fatores de Tempo , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/imunologia , Vacinas Sintéticas/administração & dosagem
8.
Phys Rev Lett ; 101(20): 207201, 2008 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-19113372

RESUMO

From neutron diffraction measurements on a quasi-1D Ising-like Co2+ spin compound BaCo2V2O8, we observed an appearance of a novel type of incommensurate ordering in magnetic fields. This ordering is essentially different from the Néel-type ordering, which is expected for the classical system, and the peculiar spin structure is caused by quantum fluctuation inherent in the quantum spin chain. A Tomonaga-Luttinger liquid nature characteristic of the gapless quantum 1D system is responsible for the realization of the incommensurate ordering.

9.
Phys Rev Lett ; 100(5): 057202, 2008 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-18352418

RESUMO

High-field specific heat measurements on BaCo(2)V(2)O(8), which is a good realization of an S=1/2 quasi-one-dimensional (1D) Ising-like antifferomagnet, have been performed in magnetic fields up to 12 T along the chain and at temperature down to 200 mK. We have found a new magnetic ordered state in the field-induced phase above H(c) approximately 3.9 T. We suggest that a novel type of the incommensurate order, which is caused by the quantum effect inherent in the S=1/2 quasi-1D Ising-like antiferromagnet, appears in the field-induced phase.

10.
Phys Rev Lett ; 99(8): 087602, 2007 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-17930982

RESUMO

High field magnetization and ESR measurements on the quasi-one-dimensional (1D) antiferromagnet BaCo(2)V(2)O(8) have been performed in magnetic fields up to 50 T along the chain. The experimental results are explained well in terms of a 1D S=1/2 antiferromagnetic XXZ model in longitudinal fields. We show that the quantum phase transition from the Néel ordered phase to the spin liquid one in the model is responsible for a peculiar order to disorder transition in BaCo(2)V(2)O(8).


Assuntos
Campos Magnéticos , Transição de Fase , Modelos Teóricos
11.
Tuberculosis (Edinb) ; 87(6): 518-25, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17720625

RESUMO

One tuberculosis vaccine candidate that has shown a promising degree of protective efficacy in guinea pigs is recombinant BCG Tokyo (Ag85A)(rBCG-Ag85A[Tokyo]). As a next step, cynomolgus monkeys were utilized because they are susceptible to Mycobacterium tuberculosis and develop a continuous course of infection that resembles that in humans both clinically and pathologically. The recombinant BCG vaccine was administered once intradermally in the back skin to three groups of cynomolgus monkeys, and its protective efficacy was compared for 4 months with that of its parental BCG Tokyo strain. Vaccination of the monkeys with the rBCG-Ag85A[Tokyo] resulted in a reduction of tubercle bacilli CFU (p<0.01) and lung pathology in animals challenged intratracheally with 3000 CFU H37Rv M. tuberculosis. Vaccination prevented an increase in the old tuberculin test after challenge with M. tuberculosis and reaction of M. tuberculosis-derived antigen. Thus, it was shown in monkeys that rBCG-Ag85A[Tokyo] induced higher protective efficacy than BCG Tokyo. This warrants further clinical evaluation.


Assuntos
Vacina BCG , Tuberculose Pulmonar/prevenção & controle , Aciltransferases/imunologia , Animais , Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Sedimentação Sanguínea , Pulmão/microbiologia , Macaca fascicularis , Masculino , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/isolamento & purificação , Radiografia , Baço/microbiologia , Teste Tuberculínico , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Vacinas de DNA/imunologia
12.
Tuberculosis (Edinb) ; 87(2): 94-101, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16815096

RESUMO

A recombinant form of BCG Tokyo with an Ag85A gene insert was administered once subcutaneously to guinea pigs and its protective efficacy was compared with that of a DNA vaccine encoding Ag85A from Mycobacterium tuberculosis administered twice to guinea pigs by epidermal gene gun bombardment. Vaccination with either the recombinant BCG Tokyo or Ag85A DNA significantly reduced the severity of pulmonary pathology and the number of pulmonary and splenic colony-forming units (cfu) (p<0.001). The recombinant BCG Tokyo was better than Ag85A DNA in terms of protective efficacy against M. tuberculosis. When immunogenic synthetic Ag85A peptide was further used as a booster together with recombinant BCG Tokyo (Ag85A) or Ag85A DNA, lung pathology was improved significantly and the number of pulmonary CFU was reduced significantly. Neither recombinant BCG Tokyo, Ag85A DNA, nor the parental BCG Tokyo protected the guinea pigs from hematogenous spread of tubercle bacilli to the spleen because splenic granulomas without central necrosis were recognized. The spleen tissues from guinea pigs vaccinated with recombinant BCG Tokyo or Ag85A DNA expressed IFN-gamma and IL-2 mRNA at significantly high levels (p<0.001) as evaluated by reverse transcription polymerase chain reaction. It is concluded that peptide boosting is important for the induction of higher protective efficacy by recombinant BCG Tokyo or a tuberculosis DNA vaccine and both recombinant BCG Tokyo (Ag85A) and Ag85A DNA vaccine induce Th2 cytokine mRNA expression significantly.


Assuntos
Aciltransferases/imunologia , Antígenos de Bactérias/imunologia , Vacina BCG/uso terapêutico , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/prevenção & controle , Vacinas de DNA/uso terapêutico , Animais , Vacina BCG/imunologia , Contagem de Colônia Microbiana , Feminino , Cobaias , Imunização Secundária , Interferon gama/imunologia , Interleucina-2/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Peptídeos/imunologia , RNA Mensageiro/análise , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , Baço/imunologia , Baço/microbiologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Vacinas de DNA/imunologia
13.
Phys Rev Lett ; 94(14): 147203, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15904101

RESUMO

Two different ferromagnetic-paramagnetic transitions are detected in (Ga,Mn)As/GaAs(001) epilayers from ac susceptibility measurements: transition at a higher temperature results from (Ga,Mn)As cluster phases with [110] uniaxial anisotropy and that at a lower temperature is associated with a ferromagnetic (Ga,Mn)As matrix with 100 cubic anisotropy. A change in the magnetic easy axis from [100] to [110] with increasing temperature can be explained by the reduced contribution of 100 cubic anisotropy to the magnetic properties above the transition temperature of the (Ga,Mn)As matrix.

14.
Phys Rev Lett ; 91(19): 197201, 2003 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-14611607

RESUMO

We report clear evidence of the ferromagnetism of gas-evaporated Pd fine particles with a clean surface. The clean Pd particle is found to have a magnetic heterostructure: the surface of the particle is ferromagnetic and the rest is paramagnetic. The size dependence of the magnetic saturation component reveals that the ferromagnetic ordering occurs only on (100) facets of the particle and that the topmost two to five layers from the surface contribute to the ferromagnetism with a magnetic moment of (0.75+/-0.31)micro(B)/atom.

15.
Phys Rev Lett ; 90(1): 016601, 2003 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-12570638

RESUMO

Spin injection is found to have a significant effect on the transport properties of the Kondo alloy Cu(Fe). When a spin-polarized electron current flows from Co into Cu(Fe) wires through the Co/Cu(Fe) interface, the resistivity of the Cu(Fe) wire is suppressed near the interface, as distinct from the ordinary logarithmic increase in the resistivity at low temperatures. For the opposite current direction, no significant changes are observed. The asymmetry of the resistivity with respect to the current direction decays with a characteristic length of 1.5+/-0.4 microm at 2.5 K as the distance from the interface is increased. Possible mechanisms for the asymmetry are discussed.

16.
J Clin Pharm Ther ; 26(5): 387-90, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11679030

RESUMO

BACKGROUND: Boric acid is generally not recognized as a poisonous substance. However, boric acid has potentially fatal actions such as hypotension, metabolic acidosis and oliguria. Death may result from circulation collapse and shock. OBJECTIVE: We present a clinical case history of the successful use of forced diuresis with furosemide and intravenous fluid for boric acid poisoning. SUBJECT: A 26-year-old female who attempted suicide by consuming a large quantity of boric acid. She was brought to the hospital in a state of clouded consciousness, fever and erythema 14 h after ingestion. METHOD: 3.25 L of intravenous fluid and 100 mg of furosemide were administered over a period of 4 h in the intensive care unit and the serum and urinary concentrations of boric acid measured. RESULTS: The elimination rate of boric acid obtained with diuresis was similar to that obtained with haemodialysis on a previous occasion when the same patient attempted suicide with boric acid. The patient showed only temporary emesis and diarrhoea along with erythema, and was moved to the general ward 4 h after admission. Although in the general ward the patient's fever persisted and nausea, vomiting and headache often recurred, possibly because of an insufficient dose of furosemide, the patient's condition steadily improved over the 64 h after admission. CONCLUSION: Forced diuresis without haemodialysis is recommended early after admission for boric acid poisoning.


Assuntos
Ácidos Bóricos/intoxicação , Diurese , Adulto , Ácidos Bóricos/sangue , Ácidos Bóricos/urina , Cuidados Críticos , Diuréticos/administração & dosagem , Diuréticos/uso terapêutico , Feminino , Hidratação , Furosemida/administração & dosagem , Furosemida/uso terapêutico , Humanos , Intoxicação/tratamento farmacológico , Intoxicação/patologia , Suicídio , Fatores de Tempo
17.
Int J Obes Relat Metab Disord ; 25(10): 1459-64, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11673766

RESUMO

OBJECTIVE: Based on the inhibitory effects of teasaponin on pancreatic lipase activity in vitro, this study was performed to clarify whether teasaponin prevented obesity induced in mice by a high-fat diet for 11 weeks. DESIGN: For in vitro experiments, assay for the inhibitory effects of teasaponin on pancreatic lipase activity was performed by measuring the rate of release of oleic acid from triolein in an assay system using triolein emulsified with lecithin, gum arabic, Triton X-100 or 4-methylumbelliferyloleate. For in vivo experiments, female ICR mice were fed a high-fat diet with or without 0.5% teasaponin for 11 weeks. RESULTS: Teasaponin competitively inhibited the hydrolysis of triolein emulsified with lecithin, gum arabic, Triton X-100 or 4-methylumbelliferyloleate. Teasaponin inhibited the elevations of plasma triacylglycerol levels 3, 4 and 5 h after oral administration of lipid emulsion containing corn oil. Teasaponin suppressed the increases in body, parametrial adipose tissue weights and diameter in adipose cell size induced by a high-fat diet. Furthermore, feeding a high-fat diet plus teasaponin had no effect on stool frequency and content, but significantly increased triacylglycerol contents in feces as compared to feeding a high-fat diet. CONCLUSIONS: The anti-obesity effects of teasaponin in high-fat diet-treated mice may be partly mediated through delaying the intestinal absorption of dietary fat by inhibiting pancreatic lipase activity.


Assuntos
Fármacos Antiobesidade/farmacologia , Gorduras na Dieta/metabolismo , Absorção Intestinal/efeitos dos fármacos , Lipase/antagonistas & inibidores , Obesidade/prevenção & controle , Chá/química , Animais , Fezes/química , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Obesidade/metabolismo , Pâncreas/enzimologia , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Triglicerídeos/análise , Trioleína/metabolismo
18.
Jpn J Cancer Res ; 92(8): 848-53, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11509116

RESUMO

We have studied the inhibitory effect of chlorophyllin-chitosan (Chl-Chi) complex, an insoluble form of chlorophyllin, on the DNA adduct formation and mutagenesis by a heterocyclic food mutagen-carcinogen, 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), in mice carrying the E. coli rpsL gene as a mutagenesis reporter. Upon administration of a diet containing 0.002% or 0.01% Trp-P-2, DNA adducts were formed in various tissues in a dose-dependent manner, with the maximum level observed in the liver. Addition of 3% Chl-Chi to the diet reduced the Trp-P-2 adduct by up to 90%. The rpsL mutant frequencies increased significantly in both the liver and spleen upon administration of a 0.01% Trp-P-2 diet. Addition of Chl-Chi to the diet decreased these induced mutant frequencies to the background level. No harmful effect of Chl-Chi was detected during these experiments. The results show that Chl-Chi may be a candidate chemopreventive agent against the genotoxic action of Trp-P-2, and possibly also other aromatic carcinogens in the diet.


Assuntos
Carbolinas/antagonistas & inibidores , Quitina/farmacologia , Clorofilídeos/farmacologia , Adutos de DNA/efeitos dos fármacos , Mutagênese/efeitos dos fármacos , Proteínas Ribossômicas/genética , Animais , Carbolinas/toxicidade , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/prevenção & controle , Quitina/análogos & derivados , Quitosana , Cromatografia em Camada Fina , Dieta , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Proteínas de Escherichia coli , Frequência do Gene , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/prevenção & controle , Camundongos , Camundongos Transgênicos , Testes de Mutagenicidade , Mutagênicos/toxicidade , Proteína S9 Ribossômica
19.
Int Immunol ; 13(8): 1075-84, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11470777

RESUMO

Expression of the human low-affinity Fc receptors for IgG (human Fc gamma RII) is differentially regulated. We report here the characterization of the promoter structure of the human Fc gamma RIIB gene and the isolation of the promoter region-binding proteins by a yeast one-hybrid assay. The minimal 154-bp region upstream from the transcription start site of the human Fc gamma RIIB gene was shown to possess promoter activity in a variety of cells. An electrophoretic mobility shift assay indicated that multiple nuclear factors in cell extracts bind to the two regions [F2-3 (-110 to -93) and F4-3 (-47 to -31)] of the human Fc gamma RIIB gene promoter. Mutation analysis indicated that GGGAGGAGC (-105 to -97) and AATTTGTTTGCC (-47 to -36) sequences are responsible for binding to nuclear factors respectively. By using GGGAGGAGC and AATTTGTTTGCC as bait sequences, we cloned two zinc-finger proteins (ZNF140 and ZNF91) that bind to the F2-3 and F4-3 regions within the promoter of the human Fc gamma RIIB gene respectively. When the ZNF140 and ZNF91 were transfected with reporter plasmid, both showed repressor activity with additive effects. Thus, these results indicate that these cloned ZNF140 and ZNF91 proteins function as repressors for the human Fc gamma RIIB transcription.


Assuntos
Antígenos CD/química , Antígenos CD/genética , Proteínas de Ligação a DNA/metabolismo , Regiões Promotoras Genéticas/imunologia , Receptores de IgG/química , Receptores de IgG/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/fisiologia , Transcrição Gênica/imunologia , Dedos de Zinco/imunologia , Regiões 5' não Traduzidas/isolamento & purificação , Sequência de Aminoácidos , Antígenos CD/isolamento & purificação , Sequência de Bases , Sítios de Ligação/genética , Sítios de Ligação/imunologia , Clonagem Molecular/métodos , Proteínas de Ligação a DNA/fisiologia , Feminino , Humanos , Fatores de Transcrição Kruppel-Like , Luciferases/biossíntese , Dados de Sequência Molecular , Receptores de IgG/isolamento & purificação
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