RESUMEN
We have investigated the in-plane local structure of the Ba0.6K0.4Fe2As2 superconductor by polarized Fe K-edge extended X-ray absorption fine structure (EXAFS) measurements with temperature. The near neighbor bond distances and their stiffness, measured by polarized EXAFS in two orthogonal directions, are different suggesting in-plane anisotropy of the atomic displacements and local orthorhombicity in the title system. The X-ray absorption near edge structure (XANES) spectra reveal anisotropy of valence electronic structure that changes anomalously below â¼100 K. The local iron magnetic moment, measured by Fe Kß X-ray emission spectroscopy (XES), increases below the anomalous temperature and shows a decrease in the vicinity of the superconducting transition temperature (Tc â¼ 36 K). The results provide a clear evidence of coupled local lattice, electronic and magnetic degrees of freedom to induce possible nematic fluctuations in an optimally hole doped iron-based superconductor.
RESUMEN
We have investigated the pinning potential of high-quality single crystals of superconducting material CaKFe4As4 having high critical current density and very high upper critical field using both magnetization relaxation measurements and frequency-dependent AC susceptibility. Preliminary studies of the superconducting transition and of the isothermal magnetization loops confirmed the high quality of the samples, while temperature dependence of the AC susceptibility in high magnetic fields show absolutely no dependence on the cooling conditions, hence, no magnetic history. From magnetization relaxation measurements were extracted the values of the normalized pinning potential U*, which reveals a clear crossover between elastic creep and plastic creep. The extremely high values of U*, up to 1200 K around the temperature of 20 K lead to a nearly zero value of the probability of thermally-activated flux jumps at temperatures of interest for high-field applications. The values of the creep exponents in the two creep regimes resulted from the analysis of the magnetization relaxation data are in complete agreement with theoretical models. Pinning potentials were also estimated, near the critical temperature, from AC susceptibility measurements, their values being close to those resulted (at the same temperature and DC field) from the magnetization relaxation data.
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Hybridization of Bogoliubov quasiparticles (BQPs) between the CuO_{2} layers in the triple-layer cuprate high-temperature superconductor Bi_{2}Sr_{2}Cu_{2}Cu_{3}O_{10+δ} is studied by angle-resolved photoemission spectroscopy (ARPES). In the superconducting state, an anticrossing gap opens between the outer- and inner-BQP bands, which we attribute primarily to interlayer single-particle hopping with possible contributions from interlayer Cooper pairing. We find that the d-wave superconducting gap of both BQP bands smoothly develops with momentum without an abrupt jump in contrast to a previous ARPES study. Hybridization between the BQPs also gradually increases in going from the off nodal to the antinodal region, which is explained by the momentum dependence of the interlayer single-particle hopping. As possible mechanisms for the enhancement of the superconducting transition temperature, the hybridization between the BQPs as well as the combination of phonon modes of the triple CuO_{2} layers and spin fluctuations represented by a four-well model are discussed.
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Mesenchymal stem cell (MSC) transplantation is an effective periodontal regenerative therapy. MSCs are multipotent, have self-renewal ability, and can differentiate into periodontal cells. However, senescence is inevitable for MSCs. In vitro, cell senescence can be induced by long-term culture with/without cell passage. However, the regulatory mechanism of MSC senescence remains unclear. Undifferentiated MSC-specific transcription factors can regulate MSC function. Herein, we identified the regulatory transcription factors involved in MSC senescence and elucidated their mechanisms of action. We cultured human MSCs (hMSCs) with repetitive cell passages to induce cell senescence and evaluated the mRNA and protein expression of cell senescence-related genes. Additionally, we silenced the cell senescence-induced transcription factors, GATA binding protein 6 (GATA6) and SRY-box 11 (SOX11), and investigated senescence-related signaling pathways. With repeated passages, the number of senescent cells increased, while the cell proliferation capacity decreased; GATA6 mRNA expression was upregulated and that of SOX11 was downregulated. Repetitive cell passages decreased Wnt and bone morphogenetic protein (BMP) signaling pathway-related gene expression. Silencing of GATA6 and SOX11 regulated Wnt and BMP signaling pathway-related genes and affected cell senescence-related genes; moreover, SOX11 silencing regulated GATA6 expression. Hence, we identified them as pair of regulatory transcription factors for cell senescence in hMSCs via the Wnt and BMP signaling pathways.
Asunto(s)
Senescencia Celular/genética , Células de la Médula Ósea/citología , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/metabolismo , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Factor de Transcripción GATA6/antagonistas & inhibidores , Factor de Transcripción GATA6/genética , Factor de Transcripción GATA6/metabolismo , Histona Desacetilasa 2/genética , Histona Desacetilasa 2/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Factores de Transcripción SOXC/antagonistas & inhibidores , Factores de Transcripción SOXC/genética , Factores de Transcripción SOXC/metabolismo , Transducción de Señal/genética , Proteínas Wnt/genética , Proteínas Wnt/metabolismoRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMEN
Improvement of the critical current density (Jc) of superconducting wires/tapes is one of the key issues in the field of superconductivity applications. Here we report the fabrication of a silver-sheathed Ba1-xNaxFe2As2 (BaNa-122) superconducting tape by using a powder-in-tube technique and its superconducting properties, in particular transport Jc, as well as the tape-core texture. The optimally-doped BaNa-122 tape with Na concentration x = 0.4 exhibits the superconducting critical temperature (Tc) of 33.7 K and high transport Jc of 4 × 104 A/cm2 at 4.2 K in a magnetic field of 4 T. Patterns of x-ray diffraction for the superconducting core show that the degree of c-axis orientation is significantly enhanced through the tape fabrication process. The tendency of c-axis orientation is advantageous for achieving higher Jc, suggesting the high potential of BaNa-122 for superconducting wire/tape applications.
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Anisotropy of transport and magnetic properties of parent compounds of iron based superconductors is a key ingredient of superconductivity. In this work, we investigate in-plane and out-of-plane properties, namely thermal, electric, thermoelectric transport and magnetic susceptibility in a high quality BaFe2As2 single crystal of the 122 parent compound, using a combined experimental and theoretical approach. Combining the ab initio calculation of the band structure and the measured in-plane and out-of-plane resistivity, we evaluate the scattering rates which turn out to be strongly anisotropic and determined by spin excitations in the antiferromagnetic state. The observed anisotropy of thermal conductivity is discussed in terms of anisotropy of sound velocities which we estimate to be [Formula: see text]. Remarkably, we find that thermal conductivity is characterized by a sizeable electronic contribution at low temperature, which is ascribed to the high purity of our crystal.
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This paper reports a multi-throughput multi-organ-on-a-chip system formed on a pneumatic pressure-driven medium circulation platform with a microplate-sized format as a novel type of microphysiological system. The pneumatic pressure-driven platform enabled parallelized multi-organ experiments (i.e. simultaneous operation of multiple multi-organ culture units) and pipette-friendly liquid handling for various conventional cell culture experiments, including cell seeding, medium change, live/dead staining, cell growth analysis, gene expression analysis of collected cells, and liquid chromatography-mass spectrometry analysis of chemical compounds in the culture medium. An eight-throughput two-organ system and a four-throughput four-organ system were constructed on a common platform, with different microfluidic plates. The two-organ system, composed of liver and cancer models, was used to demonstrate the effect of an anticancer prodrug, capecitabine (CAP), whose metabolite 5-fluorouracil (5-FU) after metabolism by HepaRG hepatic cells inhibited the proliferation of HCT-116 cancer cells. The four-organ system, composed of intestine, liver, cancer, and connective tissue models, was used to demonstrate evaluation of the effects of 5-FU and two prodrugs of 5-FU (CAP and tegafur) on multiple organ models, including cancer and connective tissue.
Asunto(s)
Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas de Cultivo de Órganos/instrumentación , Células CACO-2 , Técnicas de Cultivo de Célula/instrumentación , Diseño de Equipo , Células HCT116 , Humanos , Modelos Biológicos , PresiónRESUMEN
Conventional superconductivity is caused by electron-phonon coupling. The discovery of high-temperature superconductors raised the question of whether such strong electron-phonon coupling is realized in cuprates. Strong coupling with some collective excitation mode has been indicated by a dispersion "kink". However, there is intensive debate regarding whether the relevant coupling mode is a magnetic resonance mode or an oxygen buckling phonon mode. This ambiguity is a consequence of the energy of the main prominent kink. Here, we show a new landscape of dispersion kinks. We report that heavily overdoping a Bi2Sr2CaCu2O8+δ superconductor results in a decline of the conventional main kink and a rise of another sharp kink, along with substantial energy shifts of both. Notably, the latter kink can be ascribed only to an oxygen-breathing phonon. Hence, the multiple phonon branches provide a consistent account of our data set on the multiple kinks. Our results suggest that strong electron-phonon coupling and its dramatic change should be incorporated into or reconciled with scenarios for the evolution of high-T c superconductivity.
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BACKGROUND: Calcineurin-inhibitor-induced pain syndrome (CIPS) was used as a reference in the literature as reflex sympathetic dystrophy syndrome related to calcineurin inhibitors. Much of the literature describes CIPS that occurred after kidney and bone marrow transplantation. We describe a rare case of CIPS in induction immunosuppression before kidney transplantation, under administration of an anti-rheumatoid drug. METHODS: A 53-year-old woman had pre-status of ABO-incompatible living kidney transplantation. The patient had rheumatoid arthritis, but that was well-controlled with salazosulfapyridine as an anti-rheumatoid drug. Fourteen days before transplantation, she received induction immunosuppressive therapy consisting of tacrolimus (TAC) and mycophenolate mofetil (MMF) and she stopped taking salazosulfapyridine. The third day after that treatment, she had a high fever, fatigue, and joint pains of the knees, elbows, and wrists. RESULTS: When the patient stopped taking TAC and MMF and started taking salazosulfapyridine again, she soon recovered. Next, we challenged same induction immunosuppression therapy with administration of salazosulfapyridine; however, the patient had the same symptom. We considered that the symptom was caused by TAC or MMF, and we did not challenge-test each drug. We found that taking only TAC caused the same symptom for the patient. Also, we challenged cyclosporine (CsA) with MMF and confirmed that she did not have the symptom. CONCLUSIONS: We decided that drugs of the induction immunosuppression therapy were CsA, MMF, prednisolone, and basiliximab. The patient received induction therapy with plasmapheresis and rituximab in addition to the above-mentioned drugs, and we performed ABO-incompatible kidney transplantation for her. The post-surgical course was good, without acute rejection, and she had no pain.
Asunto(s)
Artralgia/inducido químicamente , Inhibidores de la Calcineurina/efectos adversos , Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Fallo Renal Crónico/cirugía , Trasplante de Riñón , Tacrolimus/efectos adversos , Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/complicaciones , Artritis Reumatoide/tratamiento farmacológico , Basiliximab , Incompatibilidad de Grupos Sanguíneos , Ciclosporina/uso terapéutico , Femenino , Supervivencia de Injerto , Humanos , Factores Inmunológicos/uso terapéutico , Fallo Renal Crónico/complicaciones , Persona de Mediana Edad , Ácido Micofenólico/uso terapéutico , Plasmaféresis , Cuidados Preoperatorios , Proteínas Recombinantes de Fusión/uso terapéutico , Rituximab/uso terapéutico , Sulfasalazina/uso terapéuticoRESUMEN
BACKGROUND: Urinary decoy cells develop after renal transplantation and their appearance is attributable primarily to the proliferation of polyomavirus types BK and JC. We measured the levels of these 2 viruses that cause decoy cells to appear in the urine. PATIENTS AND METHODS: BK and JC virus levels were quantified in 1182 urine samples from 335 renal transplant patients using a multiplex Taqman real-time polymerase chain reaction assay. Forty-four samples were excluded from analyses because both viruses were present at ≥10(4) copies/mL. We analyzed the relationship between viral load and the presence of urinary decoy cells. RESULTS: Decoy cells were observed in 237 of 1138 urine samples (21%) and the BK and JC viruses were positive in 205 (18%) and 455 (40%) samples, respectively. Decoy cells were observed in 0%, 21%, 67%, 87%, 100%, and 96% of urine samples when the BK viral load was <10(4), 10(4)-10(5), 10(5)-10(6), 10(6)-10(7), 10(7)-10(8), and ≥10(8) copies/mL, respectively; and in 1%, 13%, 41%, 59%, 87%, and 97% of urine samples when the JC viral load was <10(4), 10(4)-10(5), 10(5)-10(6), 10(6)-10(7), 10(7)-10(8), and ≥10(8) copies/mL, respectively. CONCLUSIONS: BK virus more frequently triggered the appearance of decoy cells than did JC virus at equivalent viral titers.
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Virus BK/aislamiento & purificación , Virus JC/aislamiento & purificación , Fallo Renal Crónico/patología , Fallo Renal Crónico/virología , Trasplante de Riñón , Infecciones por Polyomavirus/patología , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Fallo Renal Crónico/cirugía , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Urinálisis , Orina/citología , Orina/virología , Carga Viral , Adulto JovenAsunto(s)
ADP-Ribosil Ciclasa 1/metabolismo , Citotoxicidad Inmunológica/efectos de los fármacos , Interferón-alfa/farmacología , Leucemia-Linfoma de Células T del Adulto/inmunología , Glicoproteínas de Membrana/metabolismo , Linfocitos T/efectos de los fármacos , Tretinoina/farmacología , ADP-Ribosil Ciclasa 1/inmunología , Adulto , Sinergismo Farmacológico , Humanos , Interferón-alfa/administración & dosificación , Leucemia-Linfoma de Células T del Adulto/patología , Glicoproteínas de Membrana/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Tretinoina/administración & dosificación , Células Tumorales Cultivadas , Regulación hacia Arriba/efectos de los fármacosAsunto(s)
Regulación Neoplásica de la Expresión Génica/genética , Mutación , Factor 88 de Diferenciación Mieloide/genética , FN-kappa B/metabolismo , Transducción de Señal , Macroglobulinemia de Waldenström/genética , Proteína bcl-X/biosíntesis , Secuencia de Aminoácidos , Secuencia de Bases , Supervivencia Celular , Análisis Mutacional de ADN , Humanos , Immunoblotting , Inmunoprecipitación , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Factor 88 de Diferenciación Mieloide/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Transducción de Señal/fisiología , Regulación hacia Arriba , Macroglobulinemia de Waldenström/metabolismo , Proteína bcl-X/genéticaRESUMEN
The aim of this study was to investigate stomatognathic performance after mandibulectomy. Twenty-six subjects were classified into two groups: the mandibular continuity (MC) group were reconstructed and kept in MC, while the mandibular non-continuity (MNC) group lost MC. Stomatognathic performance was evaluated using the Oral Health Impact Profile in Japanese (OHIP-J), a colour-changing chewing gum, a gummy jelly, Sato's questionnaire, electromyography (EMG) of the masticatory muscles, and mandibular movement. The OHIP-J and modified Sato's questionnaire revealed that the physical and eating disability of the MNC group was significantly more severe than that of the MC group (P<0.05). The mean EMG activity of the anterior temporalis muscle in the relaxed state was significantly higher in the MNC group than in the MC group (P<0.05). The mean masticating/relaxing ratio of EMG activities for the masseter muscle was lower in the MNC group than in the MC group (P<0.05). The maximum mouth opening range of the MNC group was greater than that of the MC group (P<0.05). Accordingly, the MC group had good results for physical and eating ability. The MNC group suffered from muscle fatigue but had the advantage of a greater maximum mouth opening range.
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Mandíbula/fisiología , Neoplasias Mandibulares/cirugía , Reconstrucción Mandibular/métodos , Masticación/fisiología , Músculos Masticadores/fisiología , Salud Bucal , Anciano , Anciano de 80 o más Años , Niño , Electromiografía , Femenino , Humanos , Masculino , Mandíbula/cirugía , Persona de Mediana Edad , Fatiga Muscular/fisiología , Perfil de Impacto de Enfermedad , Colgajos Quirúrgicos , Encuestas y CuestionariosRESUMEN
In order to clarify the taxonomic position of serotypes 20, 22 and 26 of Streptococcus suis, biochemical and molecular genetic studies were performed on isolates (SUT-7, SUT-286(T), SUT-319, SUT-328 and SUT-380) reacted with specific antisera of serotypes 20, 22 or 26 from the saliva of healthy pigs as well as reference strains of serotypes 20, 22 and 26. Comparative recN gene sequencing showed high genetic relatedness among our isolates, but marked differences from the type strain S. suis NCTC 10234(T), i.e. 74.8-75.7 % sequence similarity. The genomic relatedness between the isolates and other strains of species of the genus Streptococcus, including S. suis, was calculated using the average nucleotide identity values of whole genome sequences, which indicated that serotypes 20, 22 and 26 should be removed taxonomically from S. suis and treated as a novel genomic species. Comparative sequence analysis revealed 99.0-100 % sequence similarities for the 16S rRNA genes between the reference strains of serotypes 20, 22 and 26, and our isolates. Isolate STU-286(T) had relatively high 16S rRNA gene sequence similarity with S. suis NCTC 10234(T) (98.8 %). SUT-286(T) could be distinguished from S. suis and other closely related species of the genus Streptococcus using biochemical tests. Due to its phylogenetic and phenotypic similarities to S. suis we propose naming the novel species Streptococcus parasuis sp. nov., with SUT-286(T) (â= JCM 30273(T)â= DSM 29126(T)) as the type strain.
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Filogenia , Streptococcus suis/clasificación , Streptococcus/clasificación , Animales , ADN Bacteriano/genética , Genes Bacterianos , Sueros Inmunes/inmunología , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Saliva/inmunología , Análisis de Secuencia de ADN , Serogrupo , Porcinos/inmunologíaRESUMEN
In high-transition-temperature superconducting cuprates and iron arsenides, chemical doping plays an important role in inducing superconductivity. Whereas in the cuprate case, the dominant role of doping is to inject charge carriers, the role for the iron arsenides is complex owing to carrier multiplicity and the diversity of doping. Here, we present a comparative study of the in-plane resistivity and the optical spectrum of doped BaFe2As2, which allows for separation of coherent (itinerant) and incoherent (highly dissipative) charge dynamics. The coherence of the system is controlled by doping, and the doping evolution of the charge dynamics exhibits a distinct difference between electron and hole doping. It is found in common with any type of doping that superconductivity with high transition temperature emerges when the normal-state charge dynamics maintains incoherence and when the resistivity associated with the coherent channel exhibits dominant temperature-linear dependence.
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We developed a high power supercontinuum source at a center wavelength of 1.7 µm to demonstrate highly penetrative ultrahigh-resolution optical coherence tomography (UHR-OCT). A single-wall carbon nanotube dispersed in polyimide film was used as a transparent saturable absorber in the cavity configuration and a high-repetition-rate ultrashort-pulse fiber laser was realized. The developed SC source had an output power of 60 mW, a bandwidth of 242 nm full-width at half maximum, and a repetition rate of 110 MHz. The average power and repetition rate were approximately twice as large as those of our previous SC source [20]. Using the developed SC source, UHR-OCT imaging was demonstrated. A sensitivity of 105 dB and an axial resolution of 3.2 µm in biological tissue were achieved. We compared the UHR-OCT images of some biological tissue samples measured with the developed SC source, the previous one, and one operating in the 1.3 µm wavelength region. We confirmed that the developed SC source had improved sensitivity and penetration depth for low-water-absorption samples.
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A novel galacto-oligosaccharide (GOS) was administered by gavage to groups (10 males and 10 females) of Sprague-Dawley specific pathogen-free rats for 6 weeks from day 4 after birth at doses of 0, 500, 1000, or 2000 mg/kg/day. Each pup was subjected to a variety of observations to examine for development effects/changes after birth: general condition, clinical signs, functional examinations, grip strength and spontaneous movement, body weight and feed consumption, external differentiation, ophthalmological examination, urinalysis (including water consumption), hematology, blood chemistry, necropsy, organ weight, and histopathology. During the study period, no deaths occurred in any group and there were no observed effects from administration of GOS. Therefore, it was concluded that GOS had no effects on the development of animals 4 days after birth. Since, there were no abnormalities due to administration of GOS in the macroscopic examination, organ weight or histopathology of the reproductive organs or differentiation (incisor eruption and eyelid opening) of males or females, it was concluded that repeated oral administration of GOS at 2000 mg/kg/day for 6 weeks from day 4 after birth had : no effects on postnatal development. The no observed effect level of GOS by repeated oral administration for 6 weeks from day 4 after birth was 2000 mg/kg/day for both males and females under the conditions of this study.
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Oligosacáridos/toxicidad , Prebióticos/toxicidad , Administración Oral , Factores de Edad , Animales , Conducta Animal/efectos de los fármacos , Biomarcadores/sangre , Biomarcadores/orina , Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Femenino , Masculino , Actividad Motora/efectos de los fármacos , Fuerza Muscular/efectos de los fármacos , Oligosacáridos/administración & dosificación , Ratas Sprague-Dawley , Medición de Riesgo , Factores de Tiempo , Pruebas de ToxicidadRESUMEN
The aim of this study was to clarify the usefulness of colour-changing gum in evaluating masticatory performance after mandibulectomy. Thirty-nine patients who underwent mandibulectomy between 1982 and 2010 at Kobe University Hospital were recruited in this study. There were 21 male and 18 female subjects with a mean age of 64·7 years (range: 12-89 years) at the time of surgery. The participants included six patients who underwent marginal mandibulectomy, 21 patients who underwent segmental mandibulectomy and 12 patients who underwent hemimandibulectomy. The masticatory function was evaluated using colour-changing chewing gum, gummy jelly and a modified Sato's questionnaire. In all cases, the data were obtained more than 3 months after completing the patient's final prosthesis. The colour-changing gum scores correlated with both the gummy jelly scores (r = 0·634, P < 0·001) and the total scores of the modified Sato's questionnaire (r = 0·537, P < 0·001). In conclusion, colour-changing gum is a useful item for evaluating masticatory performance after mandibulectomy.
Asunto(s)
Goma de Mascar , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Masticación/fisiología , Enfermedades de la Boca/cirugía , Cirugía Bucal/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Color , Femenino , Humanos , Masculino , Osteotomía Mandibular/efectos adversos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Adulto JovenRESUMEN
An energy gap is, in principle, a dominant parameter in superconductivity. However, this view has been challenged for the case of high-Tc cuprates, because anisotropic evolution of a d-wave-like superconducting gap with underdoping has been difficult to formulate along with a critical temperature Tc. Here we show that a nodal-gap energy 2ΔN closely follows 8.5 kBTc with underdoping and is also proportional to the product of an antinodal gap energy Δ(*) and a square-root superfluid density âPs for Bi2Sr2CaCu2O8+δ, using low-energy synchrotron-radiation angle-resolved photoemission. The quantitative relations imply that the distinction between the nodal and antinodal gaps stems from the separation of the condensation and formation of electron pairs, and that the nodal-gap suppression represents the substantial phase incoherence inherent in a strong-coupling superconducting state. These simple gap-based formulae reasonably describe a crucial part of the unconventional mechanism governing Tc.