Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 223
Filtrar
1.
J Geophys Res Space Phys ; 127(6): e2021JA030114, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35864908

RESUMO

In the present study we examine three substorm events, Events 1-3, focusing on the spatio-temporal development of auroral electrojets (AEJs) before auroral breakup. In Events 1 and 2, auroral breakup was preceded by the equatorward motion of an auroral form, and the ground magnetic field changed northward and southward in the west and east of the expected equatorward flow, respectively. Provided that these magnetic disturbances were caused by local ionospheric Hall currents, this feature suggests that the equatorward flow turned both eastward and westward as it reached the equatorward part of the auroral oval. The auroral breakup took place at the eastward-turning and westward-turning branches in Events 1 and 2, respectively, and after the auroral breakup, the westward AEJ enhanced only on the same side of the flow demarcation meridian. The zonal flow divergence is considered as an ionospheric manifestation of the braking of an earthward flow burst in the near-Earth plasma sheet and subsequent dawnward and duskward turning. Therefore, in Events 1 and 2, the auroral breakup presumably mapped to the dawnward and duskward flow branches, respectively. Moreover, for Event 3, we do not find any pre-onset auroral or magnetic features that can be associated with an equatorward flow. These findings suggest that the braking of a pre-onset earthward flow burst itself is not the direct cause of substorm onset, and therefore, the wedge current system that forms at substorm onset is distinct from the one that is considered to form as a consequence of the flow braking.

2.
J Geophys Res Space Phys ; 125(9): e2020JA028215, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33282620

RESUMO

Four closely located satellites at and inside geosynchronous orbit (GEO) provided a great opportunity to study the dynamical evolution and spatial scale of premidnight energetic particle injections inside GEO during a moderate substorm on 23 December 2016. Just following the substorm onset, the four spacecraft, a LANL satellite at GEO, the two Van Allen Probes (also called "RBSP") at ~5.8 R E, and a THEMIS satellite at ~5.3 R E, observed substorm-related particle injections and local dipolarizations near the central meridian (~22 MLT) of a wedge-like current system. The large-scale evolution of the electron and ion (H, He, and O) injections was almost identical at the two RBSP spacecraft with ~0.5 R E apart. However, the initial short-timescale particle injections exhibited a striking difference between RBSP-A and -B: RBSP-B observed an energy dispersionless injection which occurred concurrently with a transient, strong dipolarization front (DF) with a peak-to-peak amplitude of ~25 nT over ~25 s; RBSP-A measured a dispersed/weaker injection with no corresponding DF. The spatiotemporally localized DF was accompanied by an impulsive, westward electric field (~20 mV m-1). The fast, impulsive E × B drift caused the radial transport of the electron and ion injection regions from GEO to ~5.8 R E. The penetrating DF fields significantly altered the rapid energy- and pitch angle-dependent flux changes of the electrons and the H and He ions inside GEO. Such flux distributions could reflect the transient DF-related particle acceleration and/or transport processes occurring inside GEO. In contrast, O ions were little affected by the DF fields.

3.
Geophys Res Lett ; 47(14): e2020GL088227, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32999513

RESUMO

Explosive magnetotail activity has long been understood in the context of its auroral manifestations. While global models have been used to interpret and understand many magnetospheric processes, the temporal and spatial scales of some auroral forms have been inaccessible to global modeling creating a gulf between observational and theoretical studies of these phenomena. We present here an important step toward bridging this gulf using a newly developed global magnetosphere-ionosphere model with resolution capturing ≲ 30 km azimuthal scales in the auroral zone. In a global magnetohydrodynamic (MHD) simulation of the growth phase of a synthetic substorm, we find the self-consistent formation and destabilization of localized magnetic field minima in the near-Earth magnetotail. We demonstrate that this destabilization is due to ballooning-interchange instability which drives earthward entropy bubbles with embedded magnetic fronts. Finally, we show that these bubbles create localized field-aligned current structures that manifest in the ionosphere with properties matching observed auroral beads.

4.
Breast Cancer ; 25(4): 407-415, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29445928

RESUMO

BACKGROUND: Dual blockade of HER2 promises increased pathological complete response (pCR) rate compared with single blockade in the presence of chemotherapy for HER2-positive (+) primary breast cancer. Many questions remain regarding optimal duration of treatment and combination impact of endocrine therapy for luminal HER2 disease. METHODS: We designed a randomised phase II, five-arm study to evaluate the efficacy and safety of lapatinib and trastuzumab (6 weeks) followed by lapatinib and trastuzumab plus weekly paclitaxel (12 weeks) with/without prolongation of anti-HER2 therapy prior to chemotherapy (18 vs. 6 weeks), and with/without endocrine therapy in patients with HER2+ and/or oestrogen receptor (ER)+ disease. The primary endpoint was comprehensive pCR (CpCR) rate. Among the secondary endpoints, pCR (yT0-isyN0) rate, safety, and clinical response were evaluated. RESULTS: In total, 215 patients were enrolled; 212 were included in the full analysis set (median age 53.0 years; tumour size = T2, 65%; and tumour spread = N0, 55%). CpCR was achieved in 101 (47.9%) patients and was significantly higher in ER- patients than in ER+ patients (ER- 63.0%, ER+ 36.1%; P = 0.0034). pCR with pN0 was achieved in 42.2% of patients (ER- 57.6%, ER+ 30.3%). No significant difference was observed in pCR rate between prolonged exposure groups and standard groups. Better clinical response outcomes were obtained in the prolongation phase of the anti-HER2 therapy. No surplus was detected in pCR rate by adding endocrine treatment. No major safety concern was recognised by prolonging the anti-HER2 treatment or adding endocrine therapy. CONCLUSIONS: This study confirmed the therapeutic impact of lapatinib, trastuzumab, and paclitaxel therapy for each ER- and ER+ subgroup of HER2+ patients. Development of further strategies and tools is required, particularly for luminal HER2 disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/metabolismo , Feminino , Humanos , Lapatinib , Pessoa de Meia-Idade , Terapia Neoadjuvante , Paclitaxel/administração & dosagem , Quinazolinas/administração & dosagem , Receptor ErbB-2/metabolismo , Trastuzumab/administração & dosagem , Resultado do Tratamento
5.
Breast Cancer Res Treat ; 163(3): 545-554, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28337663

RESUMO

PURPOSE: This retrospective study evaluated the effect of clinical background and treatment line on time to treatment failure (TTF) in advanced/metastatic breast cancer (AMBC) patients receiving F500 in Japan (UMIN 000015168). METHODS: Patients who commenced F500 treatment were registered at 16 sites in Japan. Correlations between baseline clinicopathological factors, treatment line, and TTF were investigated by Kaplan-Meier analysis. TTF data were analyzed using univariate analysis and multivariate analysis with a Cox proportional hazards model. RESULTS: Data for 1072 patients were available; 1031 patients (96.2%) were evaluable for efficacy. F500 was administered as first-line treatment in 2.0%, second-line in 22.7%, third-line in 26.7%, and ≥fourth-line in 48.6% patients. Median TTF was 5.4 months. Multivariate analysis found that earlier F500 use (first and second vs. third vs. ≥fourth line; hazard ratio (HR) = 0.80, 95% confidence interval (CI) 0.74-0.86; P < 0.001), longer period from AMBC diagnosis to F500 use (≥3 vs. <3 years; HR 0.60, 95% CI 0.51-0.70; P < 0.001), and no prior palliative chemotherapy administered for unresectable or metastatic breast cancer (no vs. yes; HR 0.69, 95% CI 0.60-0.80; P < 0.001) were associated with significantly longer TTF. Among 691 patients, where information on histologic/nuclear grade was available, a low grade was also associated with a longer TTF, but this finding was not maintained among patients with recurrent breast cancer (N = 558). Among women with recurrent breast cancer, a longer DFI between a patient's initial breast cancer diagnosis and their recurrence was associated with a longer TTF on F500 therapy. CONCLUSIONS: Our study showed that treatment period of F500 was longer when used in earlier-line treatment. For patients on F500, TTF was also longer for patients who had not received prior palliative chemotherapy and for those who had a longer period from their AMBC diagnosis to F500 use.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Estradiol/análogos & derivados , Adulto , Idoso , Antineoplásicos Hormonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Feminino , Fulvestranto , Humanos , Japão , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Falha de Tratamento , Resultado do Tratamento
6.
Sci Rep ; 7: 41928, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28195147

RESUMO

In Lake Shinji, Japan, periodic outbreaks of musty odour have occurred since mid-May 2007. Although the substance responsible for the odour was identified as geosmin, the odour-producing organism was unknown. We cultivated an axenic unialgal strain and determined that a species of Coelosphaerium (Synechococcales) was responsible for the production of geosmin in Lake Shinji. Our analysis was conducted using gas chromatography/mass spectrometry to determine the odorous compound. To determine the algae species, it was observed by optical microscopy to describe its morphological characteristics and the polymerase chain reaction was used to characterise the nucleotide sequence of the 16S rRNA gene and the 16S-23S rRNA internal transcribed spacer region. In addition, we explored the relationship between the number of cells of the Coelosphaerium sp. and the concentration of geosmin. In conclusion, geosmin, the cause of the musty odour in Lake Shinji in autumn 2009, was produced by Coelosphaerium sp., and to our knowledge, this is the first report of a geosmin-producing species in the family Coelosphaeriaceae.


Assuntos
Cianobactérias/metabolismo , Naftóis/metabolismo , Cianobactérias/citologia , Cianobactérias/genética , Cianobactérias/isolamento & purificação , Lagos/microbiologia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética
7.
Transplant Proc ; 48(4): 1288-91, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27320606

RESUMO

Cellular survival and death are at least partially regulated by the phosphorylation of proteins. A chaperon protein, 14-3-3ζ, regulates the activity of many proteins by covering the phosphorylation site within a 14-3-3 binding motif. Therefore, regulation of 14-3-3ζ activity may affect the fate of cells subjected to cold preservation and/or hypothermic oxygenated conditions. The present study assessed whether 14-3-3ζ protects cells from hypothermic oxygenation-induced injury and clarified its role in mitochondrial functions. Human renal tubular cell line HK-2 or 14-3-3ζ-overexpressed HK-2 (ζHK-2) cells were subjected to 72 hours of normoxic cold preservation in UW solution with or without antioxidants and hydroperoxides. Cellular death, adenosine triphosphate (ATP) content, and MTT catabolism were evaluated. Deferoxamine treatment reduced cellular death and augmented ATP content in both cell types. These indices were higher in ζHK-2, regardless of deferoxamine treatment. Exposure to hydroperoxides did not affect cellular death in either cell type, whereas hydroperoxide supplementation significantly reduced ATP content, except for low-dose hydrogen peroxide in HK-2 cells. MTT assay at normal state showed higher values in ζHK-2 cells, whereas it was impaired by hydroperoxides in both cell types. These results suggest that accumulation of hydroperoxides as a byproduct of the augmented oxidative phosphorylation by 14-3-3ζ overexpression causes mitochondrial dysfunction. In conclusion, despite possessing many potentially protective functions, 14-3-3ζ exacerbates cellular injury under hypothermic oxygenated conditions. 14-3-3ζ accelerates mitochondrial functions together with iron-dependent oxidative damage. Although further investigations are necessary, upregulation of 14-3-3ζ could be a method to maintain mitochondrial function under hypothermic oxygenated conditions, as shown in hypothermic machine preservation of renal grafts, when appropriate antioxidant treatment is administered.


Assuntos
Proteínas 14-3-3/fisiologia , Túbulos Renais/fisiologia , Proteínas 14-3-3/metabolismo , Adenosina/farmacologia , Alopurinol/farmacologia , Antioxidantes/farmacologia , Soluções Cardioplégicas/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Desferroxamina/farmacologia , Glutationa/farmacologia , Humanos , Insulina/farmacologia , Túbulos Renais/citologia , Túbulos Renais/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Preservação de Órgãos/métodos , Soluções para Preservação de Órgãos/farmacologia , Fosforilação Oxidativa , Estresse Oxidativo/fisiologia , Rafinose/farmacologia , Sideróforos/farmacologia
8.
Phys Rev Lett ; 112(16): 162502, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24815642

RESUMO

The hyperfine splittings of ground state Be+11 have been measured precisely by laser-microwave double resonance spectroscopy for trapped and laser cooled beryllium ions. The ions were produced at relativistic energies and subsequently slowed down and trapped at mK temperatures. The magnetic hyperfine structure constant of Be+11 was determined to be A11=-2677.302 988(72) MHz from the measurements of the mF-mF'=0-0 field independent transition. This measurement provides essential data for the study of the distribution of the halo neutron in the single neutron halo nucleus Be11 through the Bohr-Weisskopf effect.

9.
Cancer Chemother Pharmacol ; 74(2): 229-38, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24871032

RESUMO

PURPOSE: Better treatments for triple-negative breast cancer (TNBC) are needed. To address this need, we studied the effects of preoperative metronomic paclitaxel/cyclophosphamide/capecitabine (mPCX) followed by 5-fluorouracil (FU)/epirubicin/cyclophosphamide (FEC) as preoperative chemotherapy in TNBC patients. METHODS: Forty primary TNBC patients received four cycles of metronomic paclitaxel (80 mg/m(2) on Days 1, 8, and 15), cyclophosphamide (50 mg/body daily), and capecitabine (1,200 mg/m(2) daily), followed by four cycles of 5-FU (500 mg/m(2)), epirubicin (100 mg/m(2)), and cyclophosphamide (500 mg/m(2)) every 3 weeks. The primary end point was the pathological complete response (pCR) rate. RESULTS: Forty patients formed the intent-to-treat population. The median dose intensities of paclitaxel, cyclophosphamide, and capecitabine were 89.7, 92.1, and 89.8%, respectively. Five patients discontinued mPCX and two discontinued FEC, primarily because of adverse events, resulting in a per-protocol population (PPS) of 33 patients. The pCR (ypT0/Tis ypN0) rate was 47.5% (19/40) in the intent-to-treat population and 54.5% (18/33) in the PPS. The clinical response rates were 36/40 (90.0%) and 31/33 (93.9%) in the intent-to-treat and PPS, respectively. The breast conservation rate was 72.7% (24/33), and 5/13 patients underwent partial resection instead of pre-planned total mastectomy. Grade 3-4 adverse events included neutropenia (35%), leukopenia (25%), and hand-foot syndrome (8%). CONCLUSIONS: Metronomic PCX followed by FEC chemotherapy was associated with a high pCR rate and low toxicity in TNBC patients. Further studies of this regimen in larger numbers of patients are warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Capecitabina , Ciclofosfamida/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Prognóstico , Neoplasias de Mama Triplo Negativas/patologia , Adulto Jovem
10.
Breast Cancer Res Treat ; 145(1): 143-53, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24682674

RESUMO

We investigated the disease-free survival (DFS) of HER2-positive primary breast cancer patients treated with neoadjuvant chemotherapy plus trastuzumab, as well as predictive factors for DFS and pathologic response. Data from 829 female patients treated between 2001 and 2010 were collected from 38 institutions in Japan. Predictive factors were evaluated using multivariate analyses. The 3-year DFS rate was 87 % [95 % confidence interval (CI) 85-90]. The pathologic complete response (pCR: ypT0/is + ypN0) rate was 51 %. The pCR rate was higher in the ER/PgR-negative patients than in the ER/PgR-positive patients (64 vs. 36 %, P < 0.001). Patients with pCR showed a higher DFS rate than patients without pCR (93 vs. 82 %, P < 0.001). Multivariate analysis revealed three independent predictors for poorer DFS: advanced nodal stage [hazard ratio (HR) 2.63, 95 % CI 1.36-5.21, P = 0.004 for cN2-3 vs. cN0], histological/nuclear grade 3 (HR 1.81, 95 % CI 1.15-2.91, P = 0.011), and non-pCR (HR 1.98, 95 % CI 1.22-3.24, P = 0.005). In the ER/PgR-negative dataset, non-pCR (HR 2.63, 95 % CI 1.43-4.90, P = 0.002) and clinical tumor stage (HR 2.20, 95 % CI 1.16-4.20, P = 0.017 for cT3-4 vs. cT1-2) were independent predictors for DFS, and in the ER/PgR-positive dataset, histological grade of 3 (HR 3.09, 95 % CI 1.48-6.62, P = 0.003), clinical nodal stage (HR 4.26, 95 % CI 1.53-13.14, P = 0.005 for cN2-3 vs. cN0), and young age (HR 2.40, 95 % CI 1.12-4.94, P = 0.026 for ≤40 vs. >40) were negative predictors for DFS. Strict pCR (ypT0 + ypN0) was an independent predictor for DFS in both the ER/PgR-negative and -positive datasets (HR 2.66, 95 % CI 1.31-5.97, P = 0.006 and HR 3.86, 95 % CI 1.13-24.21, P = 0.029, respectively). These results may help assure a more accurate prognosis and personalized treatment for HER2-positive breast cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Terapia Neoadjuvante , Receptor ErbB-2/metabolismo , Anticorpos Monoclonais Humanizados/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Prognóstico , Estudos Retrospectivos , Trastuzumab
11.
J Dairy Sci ; 96(8): 5174-83, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23769370

RESUMO

Understanding the influence of regional dietary factors on the flavors of milk and dairy products will provide consumers with more options and promote the conservation of regional resources and the original terroir. The objective of this study was to evaluate the influence of regional differences in feeding systems on the composition, fatty acid content, and flavor of pasteurized milk at the farm level. Nine dairy farms using grass silage (GS), 6 farms using maize silage (MS), and 4 farms using by-products (BP) as the characteristic feed components were chosen for this survey. Fresh milk was sampled once per month from September 2008 to February 2009 at each dairy farm. The percentages of GS, MS, and BP (soybean curd residue or brewer's grain) in the feed were 32.4, 22.1, and 15.1%, respectively. The milk fat, protein, and lactose contents did not differ among the milks from farms with different feeding systems. Fatty acids with chain lengths of less than C16 and saturated fatty acids were present at higher concentrations in the milks from the GS and MS farms than in the milk from the BP farms; conversely, fatty acids with chain lengths greater than C18 and unsaturated fatty acids (UFA), including mono- (MUFA) and polyunsaturated fatty acids (PUFA), were present at higher concentrations in the milks from the BP farms than in the milks from the GS farms. No significant differences were detected in milk flavor, evaluated as sweetness, body, texture, aftertaste, and palatability, between the milks from the farms with different feeding systems. The proportion of BP in the cow's diet was positively correlated with the concentrations of fatty acids with chain lengths greater than C18 and with UFA, MUFA, and PUFA. In contrast, the proportion of GS in the diet was positively associated with the levels of milk fat, protein, fatty acids with chain lengths less than C16, and SFA. The MUFA, PUFA, UFA, and fatty acids with chain lengths greater than C18 were not associated with any of the milk flavors. These results suggest the regional differences in feeding systems contribute to the differences in the fatty acid compositions of milk at the farm level. However, these differences do not influence the flavor of pasteurized milk. Thus, more specific feed profiles will be required to provide a specific regional flavor to pasteurized milk.


Assuntos
Ração Animal , Indústria de Laticínios/métodos , Qualidade dos Alimentos , Leite/química , Ração Animal/normas , Animais , Bovinos , Coleta de Dados , Ácidos Graxos/análise , Feminino , Japão , Lactose/análise , Leite/normas , Proteínas do Leite/análise , Poaceae , Silagem , Zea mays
12.
Placenta ; 32(1): 20-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21159380

RESUMO

The aim of the present study was to evaluate the relationship between the retention of fetal membranes (RFM) and apoptosis of the cells in fetal membranes. The present study investigated mRNA and protein expressions of apoptosis-regulating factors: FAS, cellular FLICE-like inhibiting protein (cFLIP), BAX, BCL2, caspase-8 (CASP8), and CASP3 in fetal membranes. Placentomes were manually collected from the uterus immediately after parturition and classified into two groups (RFM; n = 8 and non-RFM; n = 8) according to whether placental membranes were expelled or not within 12 h after delivery. FAS mRNA expression in maternal placental tissue was less in RFM cows than in non-RFM cows (P < 0.05). cFLIP mRNA expression in maternal and fetal placental tissue was greater in RFM cows than in non-RFM cows (P < 0.05). CASP3 mRNA expression in maternal placental tissue was greater in RFM cows than in non-RFM cows (P < 0.05). However, the protein expressions of FAS, cFLIP and cleaved CASP3 were not significantly different between the two groups. mRNA and protein expressions of BAX, BCL2 and CASP8 were also not significantly different between the two groups. In the immunohistochemical study, single-stranded DNA, which appears specifically in the apoptotic cells, was mainly found in the maternal placenta of non-RFM cows. Together these results suggest that RFM occurs at least in part due to a dysfunctional apoptotic process caused by the inhibition of FAS expression in the maternal placenta, and the increase of cFLIP expression in the maternal and fetal placenta.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Doenças dos Bovinos/genética , Placenta Retida/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Bovinos , Doenças dos Bovinos/metabolismo , Membranas Extraembrionárias/metabolismo , Membranas Extraembrionárias/patologia , Feminino , Feto/metabolismo , Placenta/metabolismo , Placenta Retida/metabolismo , Placenta Retida/veterinária , Gravidez
13.
Nano Lett ; 11(1): 91-5, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21114247

RESUMO

We study the plasmons confined at the gap between silver nanospheres and silver planar surfaces by means of angle- and space-resolved spectral cathodoluminescence. Plasmons in individual nanoparticles are excited by an electron beam, giving rise to light emission that is analyzed as a function of photon-energy, emission direction, and position of the beam spot. Gap plasmons are significantly red shifted due to the interaction between the particles and the metal substrate, and they are preferentially excited by positioning the beam close to the sphere centers, which results in an angular emission pattern similar to that of a dipole oriented along the surface normal. In contrast, weaker emission features are observed at higher-energies when the beam is grazing to the spheres, corresponding to the excitation of Mie plasmons like those of isolated particles, which display an angular pattern approximately mimicking a dipole parallel to the surface. Our measurements are in excellent agreement with simulations, thus providing useful insight into gap plasmons arising from the interaction between metal particles and metal substrates that are relevant for molecular sensing applications.

14.
J Phys Condens Matter ; 22(17): 176003, 2010 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-21393678

RESUMO

Magnetic and structural phase diagram in a spinel-type solid solution system Fe(1-x)Mn(x)Cr(2)O(4) has been investigated. The cubic-to-tetragonal transition temperature T(s 1) is gradually reduced by the substitution of Mn(2+) (3d(5)) for Jahn-Teller-active Fe(2+) (3d(6)) ions, implying the long-range nature of the ferroic interaction between orbitals. In the paramagnetic tetragonal phase for x < 0.5, the c parameter is shorter than a because of the anharmonicity of the elastic energy. The crystal structure further changes to orthorhombic at around the ferrimagnetic transition temperature T(N 1). T(s 1) and T(N 1) meet at x = 0.5, and Mn substitution of more than 0.5 gives rise to another tetragonal phase with a < c. The systematic change in crystal structure is discussed in terms of competition between the anharmonic lattice potential and the intra-atomic spin-orbit interaction at Fe(2+).

15.
Kyobu Geka ; 62(11): 1015-8, 2009 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-19827558

RESUMO

A 47-year-old woman with 4 episodes of right pneumothorax related to onset of menstruation was reported. A month ago, she was undergone breast conserving resection for breast cancer. She had recurrent right pneumothorax a month later and operation was performed. Thoracoscopy revealed the presence of multiple fenestrations in the right diaphragm. Thoracoscopic partial resection of the diaphragm was performed. Histopathological findings of the lesion showed spindle cells with hemosiderosis. Immunohistochemistry showed that spindle cells were estrogen receptor (ER) positive and progesterone receptor (PgR) positive, compatible with endometriosis. She was treated by tamoxifen and goserelin acetate for breast cancer and endometriosis. Two years later, gonadotropin releasing hormone (GnRH) analogue was converted from goserelin acetate to leuprorelin acetate. She was diagnosed as having recurrence of right pneumothorax 17 months later and was treated with a chest tube. Additionally, GnRH analogue was re-converted to goserelin acetate. Since then, she has been asymptomatic free for 18 months. A catamenial pneumothorax is rare disease with difficulty of diagnosis and treatment We herein report a case of the disease that was treated successfully by goserelin acetate.


Assuntos
Neoplasias da Mama/complicações , Gosserrelina/uso terapêutico , Distúrbios Menstruais/tratamento farmacológico , Pneumotórax/tratamento farmacológico , Pneumotórax/etiologia , Feminino , Humanos , Pessoa de Meia-Idade
16.
Phys Rev Lett ; 102(14): 147201, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19392476

RESUMO

The novel memory effect of a nonpolar paraelectric phase with a collinear spin structure has been observed in a magnetoelectric multiferroic material MnWO4. Since the ferroelectric polarization arises from a noncollinear spin structure, in a new class of magnetoelectric multiferroic materials with a spiral-spin structure, the information of ferroelectric domains should be lost in the collinear spin phase. However, in MnWO4, it has been found that the domain states in the ferroelectric phase are memorized even in the nonpolar phase with a collinear spin structure, when the phase transition is of the first-order type. Here we demonstrate a magnetoelectric memory effect that the ferroelectric single-domain state can be reproduced from the paraelectric phase by a magnetic field. We propose the nuclei growth model, in which the small ferroelectric embryos keep the polarization state in the nonpolar collinear spin phase.

17.
Phys Rev Lett ; 101(21): 212502, 2008 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-19113405

RESUMO

The ground state hyperfine splitting of (7)Be+ has been measured by laser-microwave double-resonance spectroscopy in the online rf trap of RIKEN's slow RI-beam facility. Be ions produced by projectile fragmentation of 13C at approximately 1 GeV were thermalized in a rf ion guide gas cell and subsequently laser cooled in the ion trap to approximately 1 microeV. This 10(15)-fold reduction of the kinetic energy allows precision spectroscopy of these ions. A magnetic hfs constant of A=-742.772 28(43) MHz was measured for 7Be+, from which a nuclear magnetic moment of mu(I)=-1.399 28(2)mu(N) was deduced.

18.
Dis Esophagus ; 21(3): 214-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18430101

RESUMO

Immunosuppressive acidic protein (IAP) suppresses several immune responses in vivo and in vitro , and high preoperative IAP levels could predict the impairment of the host's immunity. In this study prognostic significance of preoperative IAP levels was investigated in 68 esophageal cancer patients with curative resection and eight with non-curative resection. The curative group had significantly lower levels than the non-curative group (432 +/- 183 mg/mL vs. 739 +/- 235 mg/mL, P < 0.0001). The IAP levels were associated with T-status (P < 0.0001), lymphatic invasion (P < 0.05), and p-stages (P < 0.0001). When 5-year survival rate of patients with curative resection was compared by setting various cutoff values of IAP between high and low IAP groups, several cutoff points (400-580 mg/mL) were revealed to be significantly associated with survival. Setting cutoff value of IAP to 560 mg/mL resulted in a most significant difference of 5-year survival rate of patients between the high and low IAP groups (13.9% and 61.5%, P < 0.0001). These data indicate that pre-operative IAP level is a useful parameter to predict the prognosis of esophageal cancer patients after curative resection.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/mortalidade , Proteínas de Neoplasias/sangue , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
19.
Phys Rev Lett ; 99(22): 227206, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-18233323

RESUMO

For the memory application of magnetoelectric multiferroics, not only bistability (i.e., ferroelectricity) but also the switching of the polarization direction with some noneverlasting stimulus is necessary. Here, we report a novel method for the electric polarization reversal in TbMnO3 without the application of an electric field or heat. The direction of the magnetic-field-induced polarization along the a axis (Pa) is memorized even in the zero field where Pa is absent. The polarization direction can be reversed by rotating the magnetic-field direction in the ab plane.

20.
Br J Cancer ; 92(6): 1130-6, 2005 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-15770218

RESUMO

To seek for a candidate gene that would regulate tumour progression and metastasis in gastric cancer, we investigated gene expression profiles by using DNA microarray. Tumour tissue and adjacent normal tissue were obtained from 21 patients with gastric cancer and then examined for their gene expression profiles by the Gene Chip Human U95Av2 array, which includes 12 000 human genes and EST sequences. A total of 25 genes were upregulated and two genes were downregulated by at least four-fold in the tumour tissue. In a further analysis according to lymph node metastasis, the expressed levels of maspin, as well as carcinoembryonic antigen and nonspecific crossreacting antigen were significantly higher in tumours with lymph node metastasis than in those without it. Maspin expression in 85 gastric cancer patients was further investigated by using immunohistochemistry. Maspin expression was not observed in normal gastric epithelia without intestinal metaplasia. In contrast, maspin was expressed in 74 of 85 tumour tissues. There was a significant correlation between the incidence of maspin-positive tumour staining and lymph node metastasis. These results suggest that maspin has a potential role for tumour metastasis in gastric cancer.


Assuntos
Perfilação da Expressão Gênica , Serpinas/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Metilação de DNA , Feminino , Genes Supressores de Tumor , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Serpinas/análise , Neoplasias Gástricas/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...