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The bulk electronic structure of T_{d}-MoTe_{2} features large hole Fermi pockets at the Brillouin zone center (Γ) and two electron Fermi surfaces along the Γ-X direction. However, the large hole pockets, whose existence has important implications for the Weyl physics of T_{d}-MoTe_{2}, has never been conclusively detected in quantum oscillations. This raises doubt about the realizability of Majorana states in T_{d}-MoTe_{2}, because these exotic states rely on the existence of Weyl points, which originated from the same band structure predicted by density functional theory (DFT). Here, we report an unambiguous detection of these elusive hole pockets via Shubnikov-de Haas (SdH) quantum oscillations. At ambient pressure, the quantum oscillation frequencies for these pockets are 988 and 1513 T, when the magnetic field is applied along the c axis. The quasiparticle effective masses m^{*} associated with these frequencies are 1.50 and 2.77 m_{e}, respectively, indicating the importance of Coulomb interactions in this system. We further measure the SdH oscillations under pressure. At 13 kbar, we detected a peak at 1798 T with m^{*}=2.86m_{e}. Relative to the oscillation data at a lower pressure, the amplitude of this peak experienced an enhancement, which can be attributed to the reduced curvature of the hole pockets under pressure. Combining our experimental data with DFT+U calculations, where U is the Hubbard parameter, our results shed light on why these important hole pockets have not been detected until now.
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We have experimentally studied a magnetopiezoelectric effect predicted recently for magnetic metals with low crystal symmetries. In EuMnBi_{2} with antiferromagnetic Mn moments at 77 K, dynamic displacements emerge along the a direction upon application of ac electric fields in the c direction and increase in proportion to the applied electric fields. Such displacements are not observed along the c direction of EuMnBi_{2} or EuZnBi_{2} with nonmagnetic Zn ions. As temperature increases from 77 K, the displacement signals decrease and disappear at about 200 K, above which electric conduction changes from coherent to incoherent. These results demonstrate the emergence of the magnetopiezoelectric effect in a magnetic metal lacking inversion and time-reversal symmetries.
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By using a molecular beam epitaxy technique, we fabricate a new type of superconducting superlattices with controlled atomic layer thicknesses of alternating blocks between the heavy-fermion superconductor CeCoIn5, which exhibits a strong Pauli pair-breaking effect, and nonmagnetic metal YbCoIn5. The introduction of the thickness modulation of YbCoIn5 block layers breaks the inversion symmetry centered at the superconducting block of CeCoIn5. This configuration leads to dramatic changes in the temperature and angular dependence of the upper critical field, which can be understood by considering the effect of the Rashba spin-orbit interaction arising from the inversion symmetry breaking and the associated weakening of the Pauli pair-breaking effect. Since the degree of thickness modulation is a design feature of this type of superlattices, the Rashba interaction and the nature of pair breaking are largely tunable in these modulated superlattices with strong spin-orbit coupling.
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Fermionic superfluidity with a nontrivial Cooper-pairing, beyond the conventional Bardeen-Cooper-Schrieffer state, is a captivating field of study in quantum many-body systems. In particular, the search for superconducting states with finite-momentum pairs has long been a challenge, but establishing its existence has long suffered from the lack of an appropriate probe to reveal its momentum. Recently, it has been proposed that the nonreciprocal electron transport is the most powerful probe for the finite-momentum pairs, because it directly couples to the supercurrents. Here we reveal such a pairing state by the non-reciprocal transport on tricolor superlattices with strong spin-orbit coupling combined with broken inversion-symmetry consisting of atomically thin d-wave superconductor CeCoIn5. We find that while the second-harmonic resistance exhibits a distinct dip anomaly at the low-temperature (T)/high-magnetic field (H) corner in the HT-plane for H applied to the antinodal direction of the d-wave gap, such an anomaly is absent for H along the nodal direction. By carefully isolating extrinsic effects due to vortex dynamics, we reveal the presence of a non-reciprocal response originating from intrinsic superconducting properties characterized by finite-momentum pairs. We attribute the high-field state to the helical superconducting state, wherein the phase of the order parameter is spontaneously spatially modulated.
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We report a highly unusual angular variation of the upper critical field (H(c2)) in epitaxial superlattices CeCoIn(5)(n)/YbCoIn(5)(5), formed by alternating layers of n and a 5 unit-cell thick heavy-fermion superconductor CeCoIn(5) with a strong Pauli effect and normal metal YbCoIn(5), respectively. For the n=3 superlattice, H(c2)(θ) changes smoothly as a function of the field angle θ. However, close to the superconducting transition temperature, H(c2)(θ) exhibits a cusp near the parallel field (θ=0°). This cusp behavior disappears for n=4 and 5 superlattices. This sudden disappearance suggests the relative dominance of the orbital depairing effect in the n=3 superlattice, which may be due to the suppression of the Pauli effect in a system with local inversion symmetry breaking. Taking into account the temperature dependence of H(c2)(θ) as well, our results suggest that some exotic superconducting states, including a helical superconducting state, might be realized at high magnetic fields.
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BACKGROUND: Immunoglobulin (Ig) E plays an important role in the pathogenesis of allergic diseases such as atopic dermatitis and allergic asthma.We previously reported that a sulfate polysaccharide, fucoidan, suppressed IgE production by murine B cells in vitro. However, the mechanism by which fucoidan suppresses IgE production remains unclear. OBJECTIVE: We incorporated sulfate groups into cellulose and studied their biological characteristics in vitro to explore the possibility of converting biologically neutral polysaccharides to active reagents with antiallergic functions. MATERIAL AND METHODS: Cellulose was chemically processed using N,N-dimethylformamide (DMF) and DMF-sulfurtrioxide and recovered as cellulose sulfate with a molecular weight of around 10 kDa. We then studied the effect of cellulose sulfate on IgE production from B cells, IgE class-switching, and populations of IgE-secreting B cells prepared from murine spleen. We also investigated the effects of sulfated cellulose on the production of interleukin (IL) 4 and interferon (IFN) gamma and the expression of T-bet mRNA by splenic T cells. The cytotoxicity of cellulose sulfate was also examined. RESULTS: Cellulose sulfate suppressed IgE production in B cells stimulated with IL-4 and anti-CD40 antibody by inhibiting IgE class-switch recombination and decreasing the number of IgE-secreting B cells in vitro. Moreover, both cellulose sulfate and fucoidan suppressed IL-4 production and enhanced IFN-gamma production by murine T cells stimulated with anti-CD3 and anti-CD28 antibodies, despite the decrease in T-bet mRNA expression. CONCLUSIONS: Cellulose gains an antiallergic effect on B cells and T cells with the addition of sulfate groups.
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Linfócitos B/efeitos dos fármacos , Celulose/análogos & derivados , Imunoglobulina E/biossíntese , Animais , Antialérgicos/imunologia , Antialérgicos/farmacologia , Anticorpos/imunologia , Linfócitos B/imunologia , Antígenos CD40/imunologia , Células Cultivadas , Celulose/imunologia , Celulose/farmacologia , Dimetilformamida , Formamidas/química , Imunoglobulina E/imunologia , Interferon gama/imunologia , Interleucina-4/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Polissacarídeos/imunologia , Polissacarídeos/farmacologia , Baço/efeitos dos fármacos , Baço/imunologia , Proteínas com Domínio T/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologiaRESUMO
The novel spin-triplet superconductor candidate UTe2was discovered only recently at the end of 2018 and already attracted enormous attention. We review key experimental and theoretical progress which has been achieved in different laboratories. UTe2is a heavy-fermion paramagnet, but following the discovery of superconductivity, it has been expected to be close to a ferromagnetic instability, showing many similarities to the U-based ferromagnetic superconductors, URhGe and UCoGe. This view might be too simplistic. The competition between different types of magnetic interactions and the duality between the local and itinerant character of the 5fUranium electrons, as well as the shift of the U valence appear as key parameters in the rich phase diagrams discovered recently under extreme conditions like low temperature, high magnetic field, and pressure. We discuss macroscopic and microscopic experiments at low temperature to clarify the normal phase properties at ambient pressure for field applied along the three axis of this orthorhombic structure. Special attention will be given to the occurrence of a metamagnetic transition atHm= 35 T for a magnetic field applied along the hard magnetic axisb. Adding external pressure leads to strong changes in the magnetic and electronic properties with a direct feedback on superconductivity. Attention is paid on the possible evolution of the Fermi surface as a function of magnetic field and pressure. Superconductivity in UTe2is extremely rich, exhibiting various unconventional behaviors which will be highlighted. It shows an exceptionally huge superconducting upper critical field with a re-entrant behavior under magnetic field and the occurrence of multiple superconducting phases in the temperature-field-pressure phase diagrams. There is evidence for spin-triplet pairing. Experimental indications exist for chiral superconductivity and spontaneous time reversal symmetry breaking in the superconducting state. Different theoretical approaches will be described. Notably we discuss that UTe2is a possible example for the realization of a fascinating topological superconductor. Exploring superconductivity in UTe2reemphasizes that U-based heavy fermion compounds give unique examples to study and understand the strong interplay between the normal and superconducting properties in strongly correlated electron systems.
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OBJECTIVES: To establish normative reference ranges of fetal cardiac dimensions derived from volume datasets acquired using spatiotemporal image correlation with M-mode display (cardio-STIC-M). METHODS: A cross-sectional study was undertaken on singleton pregnancies with normal fetuses and accurate gestational ages. Cardio-STIC volume datasets were acquired by experienced operators using a high-resolution ultrasound machine; these were maneuvered to obtain a four chamber-view with exactly horizontal interventricular septum (IVS). Cardiac dimensions were measured in STIC-M-mode using 4D View software. RESULTS: A total of 657 measurements, at a rate of between 15 and 37 per week, were obtained. Normal reference ranges for biventricular outer diameter, left and right ventricular inner diameter, left and right ventricular wall thickness, IVS thickness, left to right ventricular diameter ratio and left and right ventricular shortening fractions were constructed based on best-fit equations as a function of gestational age, fetal head circumference and biparietal diameter. Thirty-four volume datasets of abnormal fetal hearts were also separately assessed, many of which showed abnormal cardiac dimensions. CONCLUSIONS: This is the first report on normal ranges of fetal cardiac dimensions constructed using the new cardio-STIC-M technology. Preliminary evaluation suggests that these reference ranges may be a useful tool in the assessment of fetal cardiac abnormalities.
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Ecocardiografia Quadridimensional/métodos , Coração Fetal/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Interpretação de Imagem Assistida por Computador , Variações Dependentes do Observador , Tamanho do Órgão , Gravidez , Valores de Referência , Reprodutibilidade dos Testes , Ultrassonografia Pré-Natal/métodosAssuntos
Basófilos/efeitos dos fármacos , Eritritol/efeitos adversos , Hipersensibilidade Alimentar/diagnóstico , Liberação de Histamina , Diester Fosfórico Hidrolases/imunologia , Pirofosfatases/imunologia , Adolescente , Teste de Degranulação de Basófilos , Basófilos/imunologia , Basófilos/patologia , Feminino , Hipersensibilidade Alimentar/etiologia , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/patologia , Expressão Gênica , Humanos , Diester Fosfórico Hidrolases/genética , Cultura Primária de Células , Pirofosfatases/genéticaRESUMO
Successful surgical treatment of a case of infective endocarditis with embolism to a lower extremity artery is reported. A 71-year-old man was referred to our hospital for the treatment of infective endocarditis. Echocardiography showed a vegetation on the non-coronary cusp of the aortic valve measuring 19 mm in diameter. We planned surgical treatment, including aortic valve replacement, however, embolism of a lower extremity artery by the vegetation occurred during the waiting period for the operation. We removed the offending vegetation from the popliteal artery and replaced the peccant aortic valve with a prosthetic valve in separate operations. The postoperative course was uneventful and the patient was transferred to another hospital on the 33rd day after the valve replacement surgery.
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Embolia/etiologia , Embolia/cirurgia , Endocardite/etiologia , Endocardite/cirurgia , Extremidade Inferior/irrigação sanguínea , Doença Aguda , Idoso , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Artéria Poplítea , Resultado do TratamentoRESUMO
In conventional metals, modification of electron trajectories under magnetic field gives rise to a magnetoresistance that varies quadratically at low field, followed by a saturation at high field for closed orbits on the Fermi surface. Deviations from the conventional behaviour, for example, the observation of a linear magnetoresistance, or a non-saturating magnetoresistance, have been attributed to exotic electron scattering mechanisms. Recently, linear magnetoresistance has been observed in many Dirac materials, in which the electron-electron correlation is relatively weak. The strongly correlated helimagnet CrAs undergoes a quantum phase transition to a nonmagnetic superconductor under pressure. Here we observe, near the magnetic instability, a large and non-saturating quasilinear magnetoresistance from the upper critical field to 14 T at low temperatures. We show that the quasilinear magnetoresistance may arise from an intricate interplay between a nontrivial band crossing protected by nonsymmorphic crystal symmetry and strong magnetic fluctuations.
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Monoclonal antibodies were produced against human fibroblast (beta-)interferon (IFN-beta). Four of them were directed to the determinant designated a, while the remaining 3 to another determinant named b. An IFN molecule was found to bear one each of a and b determinants arranged in such a manner that the occupation of a with the corresponding antibody did not interfere with the binding of b to its corresponding antibody, and vice versa. This allowed the development of a 2-site sandwich radioimmunoassay in which antibody to b was immobilized on wells of a microtiter plate and the bound antigen was detected by the radiolabeled antibody to a. The 2-site sandwich radioimmunoassay detected, with a high sensitivity, IFN-beta either induced from fibroblast or produced by Escherichia coli harboring the gene of IFN-beta.
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Anticorpos Monoclonais , Interferon gama/análise , Animais , Células Cultivadas , Epitopos/análise , Feminino , Fibroblastos/fisiologia , Humanos , Hibridomas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Radioimunoensaio/métodosRESUMO
Whether electrical microstimulation of a rat's striatal jaw region (SJR) in fact induced tongue or facial muscle activity in addition to jaw muscle activity was tested. Microstimulation of SJR-evoked EMG activity in a jaw-opener (anterior digastricus) and tongue-protruder (genioglossus). No activity was evoked in jaw-closers (temporalis or masseter), tongue-retractor (hyoglossus) or in facial muscles. In addition, the EMG effect could still be induced after extensive ablation of the neocortex; it was reproduced by microinjection of 50 mM kainic acid into SJR. The effective sites were histologically localized to a small central striatal region adjoining the anterior commissure. These findings may be of considerable value in understanding the striatal mechanism of orolingual dyskinesia involving involuntary jaw and tongue movements.
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Músculos Faciais/fisiologia , Músculos da Mastigação/fisiologia , Neostriado/fisiologia , Língua/fisiologia , Animais , Descorticação Cerebral , Estimulação Elétrica , Eletromiografia , Ácido Caínico/administração & dosagem , Masculino , Microeletrodos , Microinjeções , Neostriado/efeitos dos fármacos , Ratos , Estimulação QuímicaRESUMO
AIMS: Nephropathy has long been recognized as a potential complication of cyanotic congenital heart disease (CCHD). There have been few large-scale studies or clinical reports on renal impairment in patients with CCHD; similarly, very few studies have examined the drug treatment of nephropathy in CCHD. We examined the clinical characteristics and effectiveness of enalapril, an angiotensin-converting enzyme inhibitor (ACE-I), in patients with CCHD complicated with significant proteinuria. MATERIALS AND METHODS: The clinical records of 37 patients with CCHD were evaluated; all were older than 10 years of age (median 19, range from 10 to 27) and had regular check-ups, including urinalysis. The treatment criteria for enalapril administration included significant proteinuria (urinary excretion > 1.0 g/24 h), stable cardiac condition and blood pressure within the normal range. RESULTS: Eleven patients (29.7%) had persistent proteinuria, 6 patients met the enalapril treatment criteria and 5 patients were treated for more than 12 months. Enalapril apparently reduced the urinary protein excretion in 4 of the 5 patients (80%). No consistent improvement of renal function, as evidenced in the glomerular filtration rate (GFR), renal plasma flow (RPF) or filtration fraction (FF) was found in these patients, but neither were any significant adverse effects noted. CONCLUSION: The incidence of nephropathy among patients with CCHD was about 30%, which was consistent with previous studies. It is worth considering the use of ACE-I when nephropathy accompanies CCHD.
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Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/tratamento farmacológico , Síndrome Nefrótica/etiologia , Adolescente , Adulto , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Biomarcadores/sangue , Biomarcadores/urina , Biópsia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Criança , Creatinina/sangue , Enalapril/uso terapêutico , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Hexosaminidases/efeitos dos fármacos , Hexosaminidases/urina , Humanos , Japão , Rim/patologia , Rim/fisiopatologia , Testes de Função Renal , Masculino , Síndrome Nefrótica/tratamento farmacológico , Proteinúria/tratamento farmacológico , Proteinúria/etiologia , Fluxo Plasmático Renal/efeitos dos fármacos , Fluxo Plasmático Renal/fisiologia , Albumina Sérica/efeitos dos fármacos , Resultado do Tratamento , alfa-N-Acetilgalactosaminidase , Microglobulina beta-2/efeitos dos fármacos , Microglobulina beta-2/urinaRESUMO
A total of 28 surgically resected hepatocellular carcinomas, including both fresh-smeared specimens and paraffin-embedded tissues, was stained with alpha-fetoprotein (AFP) antibody. In all cases we measured the DNA contents using microspectrophotometry. In 5 cases, analyses of the nuclear DNA histogram of both the AFP-positive and negative cells from the same specimen were successfully performed. The ratio of the S-G2.M phase of the AFP-positive cells was 2.24 times more than that of the AFP-negative cells. In addition, not only the ratio of S-G2.M phase cells, but also the incidence of aneuploidy pattern of AFP positive stained cases was higher than the negative stained cases. Histologically, the AFP-positive cases contained various differentiated tissues more than the negative cases. From these results, we confirmed that AFP production was related to the growth of HCC, and the results suggest that AFP producing HCC have a higher potential for growth than AFP non-producing HCC.
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Carcinoma Hepatocelular/química , DNA de Neoplasias/análise , Neoplasias Hepáticas/química , alfa-Fetoproteínas/análise , Carcinoma Hepatocelular/patologia , Divisão Celular , DNA de Neoplasias/genética , Humanos , Neoplasias Hepáticas/patologia , Microespectrofotometria , Inclusão em Parafina , PloidiasRESUMO
Successful radiotherapy was performed for three post-operative hepatocellular carcinoma patients, two with bone metastases and one with lymph node metastasis. One patient had severe high back pain and paraplesia caused by spinal compression with bone metastasis on 5th thoracic vertebra. After a total of 45 Gy irradiations, the back pain was removed, and 9 months later the patient recovered from the paraplesia gradually and could start rehabilitation. A second patient with multiple bone metastases was very concerned about skull metastasis and severe headache. Radiation reduced the headache and the tumor vanished. A third patient with cervical lymph node metastasis was irradiated. The size of the lymph node was decreased but did not disappear. We concluded that radiotherapy for distant metastases (ie, bone, skin) in a hepatocellular carcinoma patient, can be an effective therapeutic procedure for patient complaints.
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Neoplasias Ósseas/radioterapia , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/patologia , Neoplasias Ósseas/secundário , Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/cirurgia , Terapia Combinada , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Prognóstico , Radioterapia de Alta EnergiaRESUMO
To evaluate the objective proliferative activity in HCC nuclear DNA contents were measured by means of microspectrophotometry and at the same time the immunohistochemical technique using anti-PCNA antibody was employed. Surgically resected 26 HCCs were analyzed in terms of cell proliferative activity and regional heterogeneity. The analysis was performed by immunohistochemical demonstration of PCNA and pathologic histochemical study in formalin-fixed, paraffin-embedded specimens and cytophotometric measurements of nuclear DNA contents in fresh specimens. The results were as follows. 1) Nine HCCs showed regional ploidy heterogeneity. 2) PCNA labeling index and histological grade of the marginal area was much higher than that of the central area. From these results, we concluded that in the process of the HCC progression proliferative activity was decreased in the central area and was not decreased in the marginal area.
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Carcinoma Hepatocelular/genética , DNA de Neoplasias/genética , Neoplasias Hepáticas/genética , Ploidias , Carcinoma Hepatocelular/patologia , Divisão Celular , Humanos , Neoplasias Hepáticas/patologia , Microespectrofotometria , Proteínas Nucleares/análise , Inclusão em Parafina , Antígeno Nuclear de Célula em Proliferação , Coloração e RotulagemRESUMO
To evaluate the tumor blood flow in hepatocellular carcinoma, we have introduced color Doppler imaging during operation. 37 hepatocellular carcinoma patient with 54 nodules were included in this study. Following categories were analyzed, those were detectability of pulsatile blood flow and continuous blood flow signal in the tumor, pulsatile blood flow velocity depend on tumor size and pathological feature. Even the size of the tumor is less than 1 cm in diameter in 70% of those nodules we could detect and analyze the flow signal. This new modality could have a possibility to be a useful diagnostic device for small mass lesions in the liver.