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1.
Phys Rev Lett ; 121(6): 067602, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-30141664

RESUMO

In this Letter, we report a resonant x-ray scattering measurement of stripelike charge order in the 1/8th doped component of electronically phase-separated, orthorhombic La_{2}CuO_{4+y}. This observation is coupled to the absence of any resonant (001) peak, which at different resonant energies has been identified with the presence of low-temperature-tetragonal-like structural tilt patterns or nematicity in the CuO planes. Thus, we provide evidence that structural pinning is not necessary for the formation of static charge stripes and that the relationship between charge nematicity and stripes may not be simple.

2.
Phys Rev Lett ; 120(3): 037003, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29400495

RESUMO

We present detailed neutron scattering studies of the static and dynamic stripes in an optimally doped high-temperature superconductor, La_{2}CuO_{4+y}. We observe that the dynamic stripes do not disperse towards the static stripes in the limit of vanishing energy transfer. Therefore, the dynamic stripes observed in neutron scattering experiments are not the Goldstone modes associated with the broken symmetry of the simultaneously observed static stripes, and the signals originate from different domains in the sample. These observations support real-space electronic phase separation in the crystal, where the static stripes in one phase are pinned versions of the dynamic stripes in the other, having slightly different periods. Our results explain earlier observations of unusual dispersions in underdoped La_{2-x}Sr_{x}CuO_{4} (x=0.07) and La_{2-x}Ba_{x}CuO_{4} (x=0.095).

3.
Leukemia ; 30(9): 1853-60, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27133821

RESUMO

Dasatinib (DAS) and interferon-α have antileukemic and immunostimulatory effects and induce deep responses in chronic myeloid leukemia (CML). We assigned 40 newly diagnosed chronic-phase CML patients to receive DAS 100 mg o.d. followed by addition of pegylated interferon-α2b (PegIFN) after 3 months (M3). The starting dose of PegIFN was 15 µg/week and it increased to 25 µg/week at M6 until M15. The combination was well tolerated with manageable toxicity. Of the patients, 84% remained on PegIFN at M12 and 91% (DAS) and 73% (PegIFN) of assigned dose was given. Only one patient had a pleural effusion during first year, and three more during the second year. After introduction of PegIFN we observed a steep increase in response rates. Major molecular response was achieved in 10%, 57%, 84% and 89% of patients at M3, M6, M12 and M18, respectively. At M12, MR(4) was achieved by 46% and MR(4.5) by 27% of patients. No patients progressed to advanced phase. In conclusion, the combination treatment appeared safe with very promising efficacy. A randomized comparison of DAS±PegIFN is warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Dasatinibe/administração & dosagem , Interferon-alfa/administração & dosagem , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Derrame Pleural , Proteínas Recombinantes/administração & dosagem , Indução de Remissão , Resultado do Tratamento , Adulto Jovem
4.
J Phys Condens Matter ; 28(3): 036001, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26732100

RESUMO

With the goal of elucidating the background of photoinduced ferromagnetism phenomena observed in the perovskite structured (Pr,Ca) manganites, the low-temperature magnetostructure of the material Pr0.9Ca0.1MnO3 was revised using cold neutron powder diffraction, SQUID magnetometry and ab initio calculations. Particular emphasis was placed on determining the presence of nanoscale magnetic phase separation. Previously published results of a canted A-AFM average ground state were reproduced to a good precision both experimentally and theoretically, and complemented by investigating the effects of an applied magnetic field of 2.7 T on the magnetostructure. Explicit evidence of nanoscale magnetic clusters in the material was obtained based on high-resolution neutron diffractograms. Along with several supporting arguments, we present this finding as a justification for extending the nanoscale magnetic phase separation model of manganites to the material under discussion despite its very low Ca doping level in the context of the model. In the light of the new data, we also conclude that the low temperature magnetic moment of Pr must be ca. 300% larger than previously thought in this material, close to the high spin value of 2µB per formula unit.

5.
Phys Rev Lett ; 111(22): 227001, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24329465

RESUMO

We present a combined magnetic neutron scattering and muon spin rotation study of the nature of the magnetic and superconducting phases in electronically phase separated La(2-x)Sr(x)CuO(4+y), x=0.04, 0.065, 0.09. For all samples, we find long-range modulated magnetic order below T(N) is approximately equal to Tc=39 K. In sharp contrast to oxygen-stoichiometric La(2-x)Sr(x)CuO(4), we find that the magnetic propagation vector as well as the ordered magnetic moment is independent of Sr content and consistent with that of the "striped" cuprates. Our study provides direct proof that superoxygenation in La(2-x)Sr(x)CuO(4+y) allows the spin stripe ordered phase to emerge and phase separate from superconducting regions with the hallmarks of optimally doped oxygen-stoichiometric La(2-x)Sr(x)CuO(4).

6.
Mol Hum Reprod ; 15(5): 287-94, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19282327

RESUMO

Ectopic pregnancy (EP) remains a considerable cause of morbidity and occasional mortality. Currently, there is no reliable test to differentiate ectopic from intrauterine gestation. We have previously used array technology to demonstrate that differences in gene expression in decidualized endometrium from women with ectopic and intrauterine gestations could be used to identify candidate diagnostic biomarkers for EP. The aim of this study was to further investigate the decidual gene with the highest fold increase in EP, cysteine-rich secretory protein-3 (CRISP-3). Decidualized endometrium from gestation-matched women undergoing surgical termination of pregnancy (n = 8), evacuation of uterus for miscarriage (n = 6) and surgery for EP (n = 11) was subjected to quantitative RT-PCR, morphological assessment, immunohistochemistry and western blot analysis. Sera were analysed for progesterone and human chorionic gonadotrophin (hCG) levels. Immortalized endometrial epithelial cells were cultured with physiological concentrations of hCG. CRISP-3 mRNA and protein expression were greater in endometrium from ectopic when compared with intrauterine pregnancies (P < 0.05). CRISP-3 protein was localized to epithelium and granulocytes of endometrium. CRISP-3 serum concentrations were not different in women with ectopic compared with intrauterine pregnancies. CRISP-3 expression in endometrium was not related to the degree of decidualization or to serum progesterone levels. Endometrial CRISP-3 expression was inversely proportional to serum hCG concentrations (P < 0.001). Stimulation of endometrial epithelial cells with hCG in vitro caused a reduction in CRISP-3 expression (P < 0.01). The measurement of CRISP-3 in endometrium could provide an additional tool in the diagnosis of failing early pregnancy of unknown location. The absence of a local reduction in expression of CRISP-3 in decidualized endometrium of women with EP may be due to reduced exposure to hCG due to the ectopic location of the trophoblast.


Assuntos
Gonadotropina Coriônica/metabolismo , Decídua/metabolismo , Gravidez Ectópica/metabolismo , Proteínas e Peptídeos Salivares/antagonistas & inibidores , Proteínas e Peptídeos Salivares/metabolismo , Proteínas de Plasma Seminal/antagonistas & inibidores , Proteínas de Plasma Seminal/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Linhagem Celular , Decídua/citologia , Decídua/patologia , Implantação do Embrião , Endométrio/citologia , Endométrio/metabolismo , Endométrio/patologia , Feminino , Humanos , Análise em Microsséries , Pessoa de Meia-Idade , Gravidez , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/patologia , Progesterona/sangue , Proteínas e Peptídeos Salivares/genética , Proteínas de Plasma Seminal/genética , Trofoblastos/metabolismo , Adulto Jovem
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