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1.
Proc Natl Acad Sci U S A ; 121(1): e2303423120, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38150501

RESUMO

The ability to efficiently control charge and spin in the cuprate high-temperature superconductors is crucial for fundamental research and underpins technological development. Here, we explore the tunability of magnetism, superconductivity, and crystal structure in the stripe phase of the cuprate La[Formula: see text]Ba[Formula: see text]CuO[Formula: see text], with [Formula: see text] = 0.115 and 0.135, by employing temperature-dependent (down to 400 mK) muon-spin rotation and AC susceptibility, as well as X-ray scattering experiments under compressive uniaxial stress in the CuO[Formula: see text] plane. A sixfold increase of the three-dimensional (3D) superconducting critical temperature [Formula: see text] and a full recovery of the 3D phase coherence is observed in both samples with the application of extremely low uniaxial stress of [Formula: see text]0.1 GPa. This finding demonstrates the removal of the well-known 1/8-anomaly of cuprates by uniaxial stress. On the other hand, the spin-stripe order temperature as well as the magnetic fraction at 400 mK show only a modest decrease under stress. Moreover, the onset temperatures of 3D superconductivity and spin-stripe order are very similar in the large stress regime. However, strain produces an inhomogeneous suppression of the spin-stripe order at elevated temperatures. Namely, a substantial decrease of the magnetic volume fraction and a full suppression of the low-temperature tetragonal structure is found under stress, which is a necessary condition for the development of the 3D superconducting phase with optimal [Formula: see text]. Our results evidence a remarkable cooperation between the long-range static spin-stripe order and the underlying crystalline order with the three-dimensional fully coherent superconductivity. Overall, these results suggest that the stripe- and the SC order may have a common physical mechanism.

2.
Clin Radiol ; 77(8): e652-e659, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35710528

RESUMO

AIM: To clarify the usefulness and accuracy of segmental adrenal venous sampling (sAVS) on localisation and functional diagnosis of various adrenal lesions in primary aldosteronism. MATERIALS AND METHODS: Consecutive patients (n=162) who underwent adrenalectomy and 138 patients indicated for medication following sAVS were analysed retrospectively. Based on immunohistopathological diagnosis, the positive predictive value (PPV) of computed tomography (CT)-detectable aldosterone-producing adenoma (APA) was calculated. Moreover, endocrinological and sAVS characteristics were analysed quantitatively and qualitatively among APA, CT-undetectable aldosterone-producing nodules (APNs), multiple aldosterone-producing micronodules (MAPM), and medication groups. RESULTS: The PPV of APA by sAVS was 137/141 (97.1%; 95% confidence interval, 92.9-99.2%). Compared to the medication cases, the APA group showed stronger disease activity clinically and significant differences in adrenal hormones, such as a higher aldosterone level and aldosterone-to-cortisol ratio, and lower cortisol levels in the adrenal central vein and aldosterone maximum tributaries on the dominant side after cosyntropin stimulation. The APA group shows focal aldosterone hypersecretion, such as mean number of aldosterone elevated segments (1.7 ± 0.7 versus 2 ± 0.9, p=0.003) and presence of aldosterone-not-elevated segments (93% versus 41%, p<0.001). Clinically and in terms of sAVS, APN and MAPM showed similar characteristics to APA and to the medication cases, respectively. CONCLUSION: sAVS can localise functionally active tissues of CT-detectable and CT-undetectable lesions enabling decisions on surgical or medical treatment.


Assuntos
Aldosterona , Hiperaldosteronismo , Glândulas Suprarrenais/irrigação sanguínea , Glândulas Suprarrenais/diagnóstico por imagem , Humanos , Hidrocortisona , Hiperaldosteronismo/diagnóstico por imagem , Hiperaldosteronismo/patologia , Estudos Retrospectivos
4.
Clin Exp Dermatol ; 46(7): 1255-1261, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33899950

RESUMO

BACKGROUND: Keloid lesions are characterized by mesenchymal cell proliferation and excessive extracellular matrix deposition. Previous microarray analyses have been performed to investigate the mechanism of keloid development. However, the molecular pathology that contributes to keloid development remains obscure. AIM: To explore the underlying essential molecules of keloids using microarrays. METHODS: We performed microarray analyses of keloid and nonlesional skin tissues both in vivo and in vitro. Gene expression levels were compared between tissues and cells. Quantitative reverse transcription (qRT)-PCR and immunohistochemical staining were used to determine the expression levels of molecules of interest in keloid tissues. RESULTS: Several common molecules were upregulated in both keloid tissues and keloid-lesional fibroblasts. PTPRD and NTM were upregulated both in vivo and in vitro. The genes MDFI and ITGA4 were located at the centre of the gene coexpression network analysis using keloid tissues. qRT-PCR revealed significant expression levels of PTPRD and MDFI in keloid tissues. Immunopathological staining revealed that MDFI-positive cells, which have fibroblast characteristics, were located in the keloid-associated lymphoid tissue (KALT) portion of the keloid tissue. CONCLUSION: Our gene expression profiles of keloids could distinguish the difference between lesional tissue and cultured lesional fibroblasts, and MDFI was found to be commonly expressed in both tissues and cells. Thus, MDFI-positive cells, which were located in the KALT, may play an important role in keloid pathogenesis and thus might be useful for in vitro keloid studies.


Assuntos
Perfilação da Expressão Gênica , Expressão Gênica , Queloide/genética , Fatores de Regulação Miogênica/genética , Diagnóstico Diferencial , Fibroblastos/metabolismo , Humanos , Imuno-Histoquímica , Queloide/metabolismo , Análise em Microsséries , Fatores de Regulação Miogênica/metabolismo , RNA/análise , RNA Mensageiro/metabolismo , Regulação para Cima
5.
Phys Rev Lett ; 125(9): 097005, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32915617

RESUMO

We report muon spin rotation and magnetic susceptibility experiments on in-plane stress effects on the static spin-stripe order and superconductivity in the cuprate system La_{2-x}Ba_{x}CuO_{4} with x=0.115. An extremely low uniaxial stress of ∼0.1 GPa induces a substantial decrease in the magnetic volume fraction and a dramatic rise in the onset of 3D superconductivity, from ∼10 to 32 K; however, the onset of at-least-2D superconductivity is much less sensitive to stress. These results show not only that large-volume-fraction spin-stripe order is anticorrelated with 3D superconducting coherence but also that these states are energetically very finely balanced. Moreover, the onset temperatures of 3D superconductivity and spin-stripe order are very similar in the large stress regime. These results strongly suggest a similar pairing mechanism for spin-stripe order and the spatially modulated 2D and uniform 3D superconducting orders, imposing an important constraint on theoretical models.

6.
Phys Rev Lett ; 124(18): 187002, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32441965

RESUMO

We use resonant inelastic x-ray scattering to investigate charge-stripe correlations in La_{1.675}Eu_{0.2}Sr_{0.125}CuO_{4}. By differentiating elastic from inelastic scattering, it is demonstrated that charge-stripe correlations precede both the structural low-temperature tetragonal phase and the transport-defined pseudogap onset. The scattering peak amplitude from charge stripes decays approximately as T^{-2} towards our detection limit. The in-plane integrated intensity, however, remains roughly temperature independent. Therefore, although the incommensurability shows a remarkably large increase at high temperature, our results are interpreted via a single scattering constituent. In fact, direct comparison to other stripe-ordered compounds (La_{1.875}Ba_{0.125}CuO_{4}, La_{1.475}Nd_{0.4}Sr_{0.125}CuO_{4}, and La_{1.875}Sr_{0.125}CuO_{4}) suggests a roughly constant integrated scattering intensity across all these compounds. Our results therefore provide a unifying picture for the charge-stripe ordering in La-based cuprates. As charge correlations in La_{1.675}Eu_{0.2}Sr_{0.125}CuO_{4} extend beyond the low-temperature tetragonal and pseudogap phase, their emergence heralds a spontaneous symmetry breaking in this compound.

7.
Sci Rep ; 10(1): 379, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941998

RESUMO

Humans can increase the endpoint stiffness of their arm to reduce self-generated movement variability and to reject unpredictable perturbations from the environment, like during handheld drilling, thereby increasing movement precision. Existing methods to estimate changes in the endpoint stiffness use robotic interfaces to apply position or force perturbations to measure the arm's dynamic response. We propose an alternative method of measuring changes in the power grasp force to estimate adaptations in the magnitude of the arm's endpoint stiffness. To validate our method, we examined how the strength of the power grasp, when holding onto a robotic manipulandum, affected the arm's endpoint stiffness in three different locations of the workspace. The endpoint stiffness magnitude increased linearly with the grasp force, and this linear relationship did not depend on the arm's posture or position in the workspace. The endpoint stiffness may have increased as a combination of greater grasp stiffness and greater arm stiffness, since larger co-contraction was observed in the elbow and shoulder with a stronger grasp. Changes in the grasp force could serve as a metric in assessing how humans adapt their endpoint stiffness magnitude.

8.
eNeuro ; 6(4)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31296554

RESUMO

Grasping is an action engraved in the human genome, enabling newborn infants to hang from a monkey-bar immediately after birth. The grasp force provides rich information about the brain's control of arm movements. In this study, we tested the hypothesis that the grasp force increases to improve the hand's movement precision during reaching. In two reaching experiments, subjects increased grasp force to suppress movement imprecision that arose from both self-generated motor noise and from an unpredictable environment. Furthermore, the grasp force did not increase constantly, but increased specifically along the movement where the hand's deviation was greatest. The increased grasp was premeditated and was not a reaction to environmental forces, suggesting that the central nervous system has a predictive, state-dependent model of movement precision during reaching. The grasp force provides a high temporal resolution and calibration-less estimate of movement precision adaptation.


Assuntos
Força da Mão , Intenção , Atividade Motora , Desempenho Psicomotor , Adaptação Fisiológica , Fenômenos Biomecânicos , Mãos , Humanos , Masculino
9.
J Magn Reson ; 296: 1-4, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30165264

RESUMO

We have developed a high-pressure electron spin resonance probe and successfully installed into the world's highest-field cryogen-free superconducting magnet having a maximum central field of 24.6 T. The high pressure of 2.5 GPa is achieved by the specially designed piston-cylinder pressure cell using THz-wave-transparent components. In the first application of this high-pressure high-field ESR system, we observed that the orthogonal dimer spin system SrCu2(BO3)2 undergoes a quantum phase transition from the dimer singlet ground to the plaquette singlet ground states.

11.
Br J Dermatol ; 177(6): 1732-1736, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28369922

RESUMO

Patients with deficiency of interleukin-36 receptor antagonist (DITRA), due to mutation of IL36RN, exhibit psoriatic phenotypes, typically generalized pustular psoriasis (GPP). We report a paediatric patient with DITRA, whose cutaneous lesions varied from psoriasis vulgaris in infancy to annular pustular psoriasis with acute exacerbation to GPP at 13 years of age. Conventional systemic treatments for GPP, which include oral retinoids, ciclosporin and methotrexate, are controversial in paediatric cases, because of their adverse effects and uncertain long-term consequences. Granulocyte monocyte apheresis, a process associated with few adverse events, promptly controlled the GPP of our paediatric patient, and has potential as a suitable alternative treatment for paediatric patients with DITRA.


Assuntos
Citaferese/métodos , Granulócitos , Interleucinas/genética , Monócitos , Psoríase/terapia , Adolescente , Humanos , Masculino , Mutação/genética , Psoríase/genética , Resultado do Tratamento
12.
Pediatr Surg Int ; 32(12): 1115-1119, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27815640

RESUMO

PURPOSE: Feeding and systemic hypoxia are major stresses inducing necrotizing enterocolitis (NEC). This study aims to investigate the role of systemic hypoxia in NEC and its effect before and after feeding. METHODS: Neonatal mice were studied in three groups. Control (N = 9): breast feeding; NEC A (N = 8), gavage feeding + lipopolysaccharide (LPS) + preprandial hypoxia; and NEC B (N = 9), feeding + LPS + postprandial hypoxia. Pimonidazole, a hypoxia marker, was injected intraperitoneally before ileum was harvested for histology and quantitative RT-PCR studies. Statistical analysis was done using the ANOVA and Chi-square test. RESULTS: NEC incidence was 62.5% in NEC A and 88.9% in NEC B. The mortality in NEC B (55.6%) but not A (25%) is significantly higher than control (0%, p < 0.05). Pimonidazole staining elevated in both NEC A and B with higher pimonidazole grade in NEC B (p < 0.01). Both NEC groups had increased the expression of hypoxia-related genes: HIF-1α, GLUT-1, and PHD-3 with GLUT-1 expressed more in NEC B compared with NEC A (p < 0.01). The inflammation marker, IL6, was similarly raised in both NEC A and B. CONCLUSION: Feeding and postprandial hypoxia synergistically induce intestinal hypoxia in NEC. As feeding increases intestinal oxygen demand, maintaining a balance between intestinal oxygen supply and demand is important to prevent NEC.


Assuntos
Enterocolite Necrosante/patologia , Hipóxia/patologia , Intestinos/patologia , Substitutos do Leite/administração & dosagem , Animais , Animais Recém-Nascidos , Animais Lactentes , Modelos Animais de Doenças , Nutrição Enteral , Íleo/patologia , Lipopolissacarídeos/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase
13.
Sci Rep ; 6: 25432, 2016 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-27174036

RESUMO

Perception of an object's weight is linked to its form and motion. Studies have shown the relationship between weight perception and motion in horizontal and vertical environments to be universally identical across subjects during passive observation. Here we show a contradicting finding in that not all humans share the same motion-weight pairing. A virtual environment where participants control the steepness of a slope was used to investigate the relationship between sliding motion and weight perception. Our findings showed that distinct, albeit subjective, motion-weight relationships in perception could be identified for slope environments. These individualistic perceptions were found when changes in environmental parameters governing motion were introduced, specifically inclination and surface texture. Differences in environmental parameters, combined with individual factors such as experience, affected participants' weight perception. This phenomenon may offer evidence of the central nervous system's ability to choose and combine internal models based on information from the sensory system. The results also point toward the possibility of controlling human perception by presenting strong sensory cues to manipulate the mechanisms managing internal models.


Assuntos
Movimento (Física) , Percepção de Peso , Adulto , Análise por Conglomerados , Percepção de Profundidade , Feminino , Humanos , Masculino , Modelos Teóricos , Percepção de Movimento , Psicometria , Interface Usuário-Computador , Adulto Jovem
14.
Sci Rep ; 6: 23611, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-27021464

RESUMO

In strongly correlated electron systems, enhanced fluctuations in the proximity of the ordered states of electronic degrees of freedom often induce anomalous electronic properties such as unconventional superconductivity. While spin fluctuations in the energy-momentum space have been studied widely using inelastic neutron scattering, other degrees of freedom, i.e., charge and orbital, have hardly been explored thus far. Here, we use resonant inelastic x-ray scattering to observe charge fluctuations proximate to the charge-order phase in transition metal oxides. In the two-leg ladder of Sr(14-x)Ca(x)Cu24O41, charge fluctuations are enhanced at the propagation vector of the charge order (qCO) when the order is melted by raising temperature or by doping holes. In contrast, charge fluctuations are observed not only at qCO but also at other momenta in a geometrically frustrated triangular bilayer lattice of LuFe2O4. The observed charge fluctuations have a high energy (~1 eV), suggesting that the Coulomb repulsion between electrons plays an important role in the formation of the charge order.

15.
Nat Commun ; 7: 10567, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26843063

RESUMO

In the hole-doped cuprates, a small number of carriers suppresses antiferromagnetism and induces superconductivity. In the electron-doped cuprates, on the other hand, superconductivity appears only in a narrow window of high-doped Ce concentration after reduction annealing, and strong antiferromagnetic correlation persists in the superconducting phase. Recently, Pr(1.3-x)La0.7Ce(x)CuO4 (PLCCO) bulk single crystals annealed by a protect annealing method showed a high critical temperature of around 27 K for small Ce content down to 0.05. Here, by angle-resolved photoemission spectroscopy measurements of PLCCO crystals, we observed a sharp quasi-particle peak on the entire Fermi surface without signature of an antiferromagnetic pseudogap unlike all the previous work, indicating a dramatic reduction of antiferromagnetic correlation length and/or of magnetic moments. The superconducting state was found to extend over a wide electron concentration range. The present results fundamentally challenge the long-standing picture on the electronic structure in the electron-doped regime.

16.
Br J Dermatol ; 173(4): 1054-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25973640

RESUMO

Docetaxel and paclitaxel are widely used in the treatment of various malignant neoplasms. Taxane-induced sclerosis is dose-dependent and usually not generalized. Little information on the pathogenesis of scleroderma is currently available. Here, we report a case of generalized scleroderma and a case of early-stage oedematous sclerosis, both of which presented with intense versican deposits after administration of taxane for angiosarcoma.


Assuntos
Glicosaminoglicanos/metabolismo , Couro Cabeludo/patologia , Esclerodermia Localizada/induzido quimicamente , Taxoides/efeitos adversos , Versicanas/metabolismo , Docetaxel , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Hemangiossarcoma/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose/induzido quimicamente , Neoplasias Cutâneas/tratamento farmacológico
17.
Phys Rev Lett ; 114(5): 056402, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25699459

RESUMO

We report on the real space profile of spin polarons in the quasi-two-dimensional frustrated dimer spin system SrCu(2)(BO(3))(2) doped with 0.16% of Zn. The (11)B nuclear magnetic resonance spectrum exhibits 15 additional boron sites near nonmagnetic Zn impurities. With the help of exact diagonalizations of finite clusters, we have deduced from the boron spectrum, the distribution of local magnetizations at the Cu sites with fine spatial resolution, providing direct evidence for an extended spin polaron. The results are confronted with those of other experiments performed on doped and undoped samples of SrCu(2)(BO(3))(2).

18.
Sci Rep ; 4: 5592, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24998816

RESUMO

Structural phase separation in AxFe2-ySe2 system has been studied by different experimental techniques, however, it should be important to know how the electronic uniformity is influenced, on which length scale the electronic phases coexist, and what is their spatial distribution. Here, we have used novel scanning photoelectron microscopy (SPEM) to study the electronic phase separation in KxFe2-ySe2, providing a direct measurement of the topological spatial distribution of the different electronic phases. The SPEM results reveal a peculiar interconnected conducting filamentary phase that is embedded in the insulating texture. The filamentary structure with a particular topological geometry could be important for the high Tc superconductivity in the presence of a phase with a large magnetic moment in AxFe2-ySe2 materials.

19.
Neuroscience ; 274: 383-92, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-24912028

RESUMO

Previous neuroimaging studies of response inhibition have examined correlations between behavioral efficiency and brain activity, but the temporal stability of the correlations has largely been ignored. The present functional magnetic resonance imaging (fMRI) study demonstrates the temporal changes of the brain activity associated with performance efficiency that led to more robust brain-behavior correlations in a later part of the experimental sessions. Participants performed a stop-signal task requiring inhibition of inappropriate responses, where more efficient behavioral performance is reflected in a shorter stop-signal reaction time (SSRT). Among across-subject negative correlations between the brain activity and the SSRT, the majority of the negative correlations were observed in the second half of experimental sessions. In the cerebellar region that showed the greatest difference in correlations between the second and the first halves, the brain activity increased in efficient performers, whereas the brain activity decreased in poor performers. These results suggest the existence of multiple brain mechanisms that increase and decrease the brain activity depending on the behavioral efficiency of the performers. More practically, these results indicate that robust brain-behavior correlations can more effectively be detected in a later part of the experimental sessions.


Assuntos
Encéfalo/fisiologia , Inibição Psicológica , Desempenho Psicomotor/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tempo de Reação/fisiologia , Adulto Jovem
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