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1.
Inorg Chem ; 63(5): 2553-2561, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38253512

RESUMEN

The structural and superconducting properties of the Bi-based compound Bi2Pd3Se2 were investigated over a wide pressure range. The prepared Bi2Pd3Se2 sample was a superconductor with a superconducting transition temperature, Tc, of approximately 3.0 K, which differed from a previous report (Tc of less than 1.0 K). At ambient pressure, the powder X-ray diffraction (XRD) pattern of the Bi2Pd3Se2 sample was consistent with that previously reported for Bi2Pd3Se2. The Rietveld method was used to refine the crystal structure, which had a space group of C2/m (No. 12), as reported previously. This compound showed no clear anomaly due to the charge-density-wave (CDW) transition, as seen from the temperature dependence of magnetic susceptibility. However, the temperature dependence of electrical resistivity indicated a clear anomaly, presumably because of the CDW transition in the low-pressure range; the CDW transition temperature was approximately 230 K. The XRD patterns of the Bi2Pd3Se2 sample were measured at 0.160-22.7 GPa, and the patterns were well analyzed by both the Le Bail and Rietveld refinement methods, showing no structural phase transitions in the above pressure range. The pressure dependence of Tc of Bi2Pd3Se2 was recorded based on the temperature dependence of the electrical resistance, which showed an almost constant Tc at 0-13.7 GPa, and the Tc-pressure (p) behavior was fully discussed.

2.
Phys Rev Lett ; 124(8): 087202, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32167310

RESUMEN

Antiferromagnet Mn_{3}P with Neel temperature T_{N}=30 K is composed of Mn tetrahedrons and zigzag chains formed by three inequivalent Mn sites. Due to the nearly frustrated lattice with many short Mn-Mn bonds, competition of the exchange interactions is expected. We here investigate the magnetic structure and physical properties including pressure effect in single crystals of this material, and reveal a complex yet well-ordered helimagnetic structure. The itinerant character of this materials is strong, and the ordered state with small magnetic moments is easily suppressed under pressure, exhibiting a quantum critical point at ∼1.6 GPa. The remarkable mass renormalization, even in the ordered state, and an incoherent-coherent crossover in the low-temperature region, characterize an unusual electronic state in Mn_{3}P, which is most likely effected by the underlying frustration effect.

3.
Mod Rheumatol ; 23(3): 547-53, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22752504

RESUMEN

OBJECTIVE: To compare Behçet's syndrome (BS) cohorts from the US and Japan in terms of rates of concordance with the International Study Group (ISG) criteria and Japanese criteria, disease manifestations, and treatment. METHODS: All BS patients seen at the NYU Hospital for Joint Diseases in the US and the Kameda Medical Center and St. Luke's International Hospital in Japan between 2003 and 2010 were included. Diagnosis of BS was made on the basis of clinical manifestations and the clinical decisions of experienced specialists familiar with BS. We classified the patients into complete and incomplete types based on their symptoms; both complete or incomplete types were assumed to fulfil the Japanese criteria. RESULTS: A total of 769 patients (US n = 634, Japan n = 135) were reviewed. 61.5 % in the US and 63.7 % in Japan fulfilled the ISG criteria. Similarly, there was no difference in the proportions of US and Japanese patients who fulfilled the Japanese criteria. Japanese patients were less likely to be female and to have genital ulcers, but were more likely to have epididymitis and pulmonary disease. Significantly more patients were treated with colchicine, sulfasalazine/mesalazine, and NSAIDs in Japan, while significantly more patients in the US received first-line immunosuppressants. CONCLUSIONS: The concordance rates for ISG and Japanese criteria fulfillment in the US and Japan were not significantly different. These findings could help to clarify regional differences in the diagnostic and clinical features of BS.


Asunto(s)
Síndrome de Behçet/diagnóstico , Adulto , Edad de Inicio , Antiinflamatorios/uso terapéutico , Síndrome de Behçet/tratamiento farmacológico , Estudios de Cohortes , Femenino , Humanos , Inmunosupresores/uso terapéutico , Japón , Masculino , Persona de Mediana Edad , Estados Unidos
4.
Rheumatology (Oxford) ; 50(11): 2093-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21890622

RESUMEN

OBJECTIVE: To assess the effectiveness, drug survival and safety of tocilizumab compared with TNF-α inhibitors in clinical practice. METHODS: Patients in the Cohort of Arthritis Biologic Users at Kameda Institute (CABUKI) registry who were on biologics during July 2003 to October 2010 were included. Remission rates at 6 months, Kaplan-Meier drug survival estimates and serious adverse event (SAE) rates were compared. RESULTS: A total of 247 RA patients were analysed. For first-line biologic users, the 6-month 28-joint DAS (DAS-28)-ESR remission rates were 66.7% for tocilizumab vs 25.8% for TNF inhibitors (P < 0.001, Fisher's exact test). This advantage disappeared with the application of the newly suggested Boolean remission criterion for clinical trials: 0% for tocilizumab vs 8.2% for TNF inhibitors (P = 0.367, Fisher's exact test). Tocilizumab users in DAS-28-ESR remission had lower mean ESR (3.9 mm/h for tocilizumab vs 7.9 mm/h for TNF inhibitors, P = 0.026, t-test) and higher mean swollen joint count (2.6 for tocilizumab vs 1.3 for TNF inhibitors, P = 0.036, t-test), thus failing to meet the more stringent Boolean criteria. First- and second-line tocilizumab users showed similar drug survival and SAE rates compared with TNF inhibitor users. CONCLUSION: Tocilizumab had drug survival and safety profiles similar to those of TNF inhibitors in this Japanese single-centre registry. Tocilizumab was superior to TNF inhibitors when compared at 6 months by DAS-28-ESR remission. However, the newly suggested Boolean criteria are more appropriate measures of effectiveness as DAS-28-ESR remission by tocilizumab was mainly due to very low ESR in our study population.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adalimumab , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Antirreumáticos/efectos adversos , Artritis/fisiopatología , Productos Biológicos/efectos adversos , Tolerancia a Medicamentos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Etanercept , Femenino , Hospitales Comunitarios , Humanos , Inmunoglobulina G/uso terapéutico , Infliximab , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Inducción de Remisión
5.
Nature ; 436(7048): 238-41, 2005 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-16015325

RESUMEN

Metal-organic microporous materials (MOMs) have attracted wide scientific attention owing to their unusual structure and properties, as well as commercial interest due to their potential applications in storage, separation and heterogeneous catalysis. One of the advantages of MOMs compared to other microporous materials, such as activated carbons, is their ability to exhibit a variety of pore surface properties such as hydrophilicity and chirality, as a result of the controlled incorporation of organic functional groups into the pore walls. This capability means that the pore surfaces of MOMs could be designed to adsorb specific molecules; but few design strategies for the adsorption of small molecules have been established so far. Here we report high levels of selective sorption of acetylene molecules as compared to a very similar molecule, carbon dioxide, onto the functionalized surface of a MOM. The acetylene molecules are held at a periodic distance from one another by hydrogen bonding between two non-coordinated oxygen atoms in the nanoscale pore wall of the MOM and the two hydrogen atoms of the acetylene molecule. This permits the stable storage of acetylene at a density 200 times the safe compression limit of free acetylene at room temperature.

6.
Gan To Kagaku Ryoho ; 38(5): 853-5, 2011 May.
Artículo en Japonés | MEDLINE | ID: mdl-21566453

RESUMEN

A 71-year-old male with unresectable pancreatic cancer treated with gemcitabine (GEM) by another doctor came to our hospital because of stenosis of duodenum and hydronephrosis. There was peritoneal dissemination in his abdominal cavity, and gastro-jejunostomy was performed. After surgery, GEM therapy was continued until he was judged as PD. The regimen was switched to S-1/GEM combination therapy. After that, the tumor marker was down to within normal range, and abdominal symptoms improved. He is now being treated as an outpatient. S-1/GEM combination therapy is effective for patients with unresectable advanced pancreatic cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Desoxicitidina/análogos & derivados , Ácido Oxónico/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Terapia Recuperativa , Tegafur/uso terapéutico , Terapia Combinada , Desoxicitidina/administración & dosificación , Desoxicitidina/uso terapéutico , Combinación de Medicamentos , Humanos , Masculino , Ácido Oxónico/administración & dosificación , Neoplasias Pancreáticas/cirugía , Tegafur/administración & dosificación , Gemcitabina
7.
Mod Rheumatol ; 20(2): 196-9, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19937460

RESUMEN

We report a novel case of eosinophilic orbital myositis associated with Churg-Strauss syndrome. A 56-year-old man with a 20-year history of chronic sinusitis and seasonal allergic rhinitis was admitted because of fever, swelling of cheeks and extremities, diplopia, and eosinophilia. With findings from gadolinium-enhanced FST1WI of the orbits and a muscle biopsy of the skeletal muscle, the diagnosis was made. He was treated with oral corticosteroid, and his symptoms rapidly improved.


Asunto(s)
Síndrome de Churg-Strauss/complicaciones , Eosinofilia/complicaciones , Miositis Orbitaria/complicaciones , Humanos , Masculino , Persona de Mediana Edad
8.
Nephron Exp Nephrol ; 113(3): e89-96, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19684413

RESUMEN

BACKGROUND/AIMS: Morphological change of podocytes is closely correlated with the development of proteinuria. Podocalyxin is a major sialoglycoprotein of the podocytes and is thought to be involved in the maintenance of the foot processes structure. Our aim was to examine the mechanism by which podocalyxin contributes to the morphological change of podocytes. METHODS: We searched protein(s) which coprecipitate with podocalyxin using rat glomerular lysate. Localization of podocalyxin and the coprecipitated protein, cortactin, was studied in a model of puromycin aminonucleoside (PAN) nephrosis by immunocytochemistry. Tyrosine phosphorylation of cortactin was examined. Association of the podocalyxin/cortactin complex with the actin cytoskeleton was evaluated by extraction with Triton-X and immunoblotting. RESULTS: Cortactin was found to be co-immunoprecipitated with podocalyxin. Immunocytochemical analysis revealed that these 2 proteins colocalized in the apical side of podocytes. In PAN nephrosis, localization of cortactin was altered after the onset of proteinuria, with increased tyrosine phosphorylation. Simultaneously, the dissociation of the podocalyxin/cortactin complex from the actin cytoskeleton was induced. CONCLUSIONS: These results indicate that cortactin mediates interaction between podocalyxin and actin filaments in podocytes and that alteration of this interaction may play a role in the process of morphological change of podocytes.


Asunto(s)
Cortactina/metabolismo , Podocitos/efectos de los fármacos , Sialoglicoproteínas/metabolismo , Animales , Citoesqueleto/metabolismo , Glomérulos Renales/metabolismo , Nefrosis/inducido químicamente , Nefrosis/metabolismo , Fosforilación , Podocitos/citología , Proteinuria/etiología , Puromicina Aminonucleósido , Ratas , Ratas Wistar , Sialoglicoproteínas/inmunología
9.
J Nanosci Nanotechnol ; 9(1): 69-76, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19441280

RESUMEN

The crystal structure of a microporous coordination polymer with adsorbed methane gas was determined by in situ synchrotron powder diffraction of the gas adsorption and the MEM (maximum entropy method)/Rietveld method. Methane molecules were found to be adsorbed forming a one-dimensional array in the nanochannels of the polymer. The MEM charge density distribution of the adsorbed methane molecules indicated some protrusions which were not observed in that of a spherical atom of adsorbed argon. This was interpreted as a mixed distribution of two uniaxially rotating molecules with different pivotal axes. The methane molecules displayed hindered rotation depending on the shape of the nanopore surface. This result indicates the capability to control the molecular arrangement and orientation by the adsorption of gas molecules on the precisely designed nanopores of coordination polymers.

11.
Knee ; 14(1): 59-62, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17169564

RESUMEN

Periprosthetic supracondylar femoral fractures after total knee arthroplasty (TKA) are difficult surgical problems. We report a case of an 84-year-old female, in which an original method was applied to treat a periprosthetic supracondylar femoral nonunion just proximal a femoral component. The new method features extending the stem of the femoral component with a Küntcher nail. Eventually bony union was obtained and the patient is now able to walk without any support.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Clavos Ortopédicos , Fracturas del Fémur/cirugía , Fijación Interna de Fracturas/métodos , Accidentes por Caídas , Anciano de 80 o más Años , Femenino , Humanos , Reoperación
12.
Clin Rheumatol ; 25(4): 579-82, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16568213

RESUMEN

A 45-year-old Japanese male was diagnosed with adult onset Still's disease (AOSD). High-dose corticosteroid initially resolved the illness; however, high fever, maculopalpular rashes, arthralgia, and acute pericarditis rapidly recurred, and were followed by a somnolent state without focal signs. A diagnosis of corticosteroid resistant, severe, recurrent AOSD was made, and double-filtration plasmapheresis (DFPP) was performed immediately. The somnolent state began to resolve during the first plasmapheresis procedure, and the other symptoms resolved shortly thereafter. DFPP theoretically removes monocyte-activating cytokines, such as monocyte colony-stimulating factor (M-CSF) from the circulation, and therefore may prove to be an effective treatment for corticosteroid resistant, rapidly developing cases of AOSD.


Asunto(s)
Plasmaféresis/métodos , Enfermedad de Still del Adulto/terapia , Corticoesteroides/farmacología , Filtración , Humanos , Japón , Masculino , Persona de Mediana Edad , Recurrencia , Inducción de Remisión , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
13.
J Phys Condens Matter ; 28(44): 444001, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27604421

RESUMEN

Potassium-doped picene (K3.0picene) with a superconducting transition temperature (T C) as high as 14 K at ambient pressure has been prepared using an annealing technique. The shielding fraction of this sample was 5.4% at 0 GPa. The T C showed a positive pressure-dependence and reached 19 K at 1.13 GPa. The shielding fraction also reached 18.5%. To investigate the chemical composition and the state of the picene skeleton in the superconducting sample, we used energy-dispersive x-ray (EDX) spectroscopy, MALDI-time-of-flight (MALDI-TOF) mass spectroscopy and x-ray diffraction (XRD). Both EDX and MALDI-TOF indicated no contamination with materials other than K-doped picene or K-doped picene fragments, and supported the preservation of the picene skeleton. However, it was also found that a magnetic K-doped picene sample consisted mainly of picene fragments or K-doped picene fragments. Thus, removal of the component contributing the magnetic quality to a superconducting sample should enhance the volume fraction.

14.
J Phys Chem B ; 109(49): 23378-85, 2005 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-16375310

RESUMEN

Molecules and atoms confined in a nanospace may have properties distinctly different from those of the bulk fluid, owing to the formation of a specific molecular array characteristic of nanospace. In situ synchrotron powder X-ray diffraction measurements have been used to observe confined guest molecules such as N2, O2, Ar, and CH4 in the well-regulated ultramicropore of a copper coordination polymer, 1 ([Cu2(pzdc)2pyz]: pzdc = 2,3-pyrazinedicarboxylate and pyz = pyrazine). The obtained crystal structures indicate that guest molecules are confined in a linear fashion to form crystalline-like regular ordered arrays, in contrast to the situation in the gas and liquid state, even at temperatures above the boiling point, and the ordered arrays are characteristic of the kind of gas molecule and the geometrical and potential properties of the ultramicropore of 1.

15.
Knee ; 12(6): 447-53, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15967667

RESUMEN

In evaluating patello-femoral alignment, it is not enough to assess the conformity of the joint two-dimensionally, the direction of the extensor mechanism must be examined three-dimensionally. Using magnetic resonance imaging (MRI), we adopted an ideal extensor mechanism plane intersecting the patellar facet of the femur centrally and perpendicularly. We evaluated the alignment according to the extent to which the patella and/or the tibial tuberosity deviated from the plane. The results suggested that our method is useful for indicating proximal and distal realignment. Furthermore, two-dimensional finite element analysis in the patello-femoral joint showed that peak stress was significantly higher in the dislocation group than in the no-dislocation group. This indicates that osteoarthritic change in the future is a risk in the dislocation group.


Asunto(s)
Fémur/fisiología , Luxación de la Rodilla/fisiopatología , Articulación de la Rodilla/fisiología , Imagen por Resonancia Magnética/métodos , Rótula/fisiología , Adolescente , Adulto , Femenino , Fémur/patología , Análisis de Elementos Finitos , Humanos , Luxación de la Rodilla/patología , Articulación de la Rodilla/patología , Masculino , Persona de Mediana Edad , Rótula/patología , Soporte de Peso/fisiología
16.
Sci Rep ; 5: 9477, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25828620

RESUMEN

The pressure dependence of the superconducting transition temperature (Tc) and unit cell metrics of tetragonal (NH3)yCs0.4FeSe were investigated in high pressures up to 41 GPa. The Tc decreases with increasing pressure up to 13 GPa, which can be clearly correlated with the pressure dependence of c (or FeSe layer spacing). The Tc vs. c plot is compared with those of various (NH3)yMxFeSe (M: metal atoms) materials exhibiting different Tc and c, showing that the Tc is universally related to c. This behaviour means that a decrease in two-dimensionality lowers the Tc. No superconductivity was observed down to 4.3 K in (NH3)yCs0.4FeSe at 11 and 13 GPa. Surprisingly, superconductivity re-appeared rapidly above 13 GPa, with the Tc reaching 49 K at 21 GPa. The appearance of a new superconducting phase is not accompanied by a structural transition, as evidenced by pressure-dependent XRD. Furthermore, Tc slowly decreased with increasing pressure above 21 GPa, and at 41 GPa superconductivity disappeared entirely at temperatures above 4.9 K. The observation of a double-dome superconducting phase may provide a hint for pursuing the superconducting coupling-mechanism of ammoniated/non-ammoniated metal-doped FeSe.

17.
Arthroscopy ; 20(9): 981-6, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15525932

RESUMEN

Abstract The prognosis of osteochondritis dissecans (OCD) depends on the age of manifestation and the size of the lesion. Before epiphyseal closure, OCD usually responds well to the restriction of the patient's sporting activities. Surgical intervention is not always necessary. However, if the disease manifests after epiphyseal closure, it often needs surgical treatment because the lesion is usually found at an advanced stage (International Cartilage Repair Society [ICR] OCD II or more). Furthermore, if a massive lesion develops to separation (ICR OCD II or III) or displaced loose bodies (ICR OCD IV), despite restriction of sporting activities, the prognosis is poor. This report discusses 2 cases of OCD. One patient had a massive stage ICR I lesion, although the disease was found before epiphyseal closure. In the other patient, a 22-year-old man, a large separated fragment (ICR OCD IV) was found after epiphyseal closure. The separated surfaces of the fragment and the mother bed had become sclerotic. Cylindrical osteochondral grafts using jigs for Mosaicplasty (Smith & Nephew, Andover, MA) were performed on the 2 patients, both of whom made successful recoveries. These cases suggest that cylindrical osteochondral grafting is a useful procedure for difficult cases of large lesion size or late manifestation.


Asunto(s)
Cartílago Articular/trasplante , Osteocondritis Disecante/cirugía , Adulto , Niño , Humanos , Masculino
18.
Knee ; 10(2): 135-8, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12787995

RESUMEN

Procedures for the treatment of patello-femoral malalignment are grouped into two categories, proximal realignment and distal realignment. However, no clear indications in respect of these realignments have been reported. We have tried to evaluate patello-femoral alignment three-dimensionally using CT. The results lead us to group patients with recurrent patella dislocation into three types. Type 1 comprises patients with normal patello-femoral alignment. Type 2 comprises patients whose patella only deviates laterally and who need proximal realignment. Type 3 comprises patients whose patella and tibial tuberosity both deviate laterally and who need both proximal and distal realignment.


Asunto(s)
Imagenología Tridimensional , Luxaciones Articulares/clasificación , Luxaciones Articulares/diagnóstico por imagen , Articulación de la Rodilla , Tomografía Computarizada por Rayos X , Adolescente , Estudios de Casos y Controles , Femenino , Humanos , Luxaciones Articulares/cirugía , Masculino , Procedimientos Ortopédicos , Rótula , Pronóstico
19.
Knee ; 9(2): 165-7, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11950585

RESUMEN

Procollagen II C peptide is used as a joint fluid marker of collagen synthesis by chondrocytes in patients with osteoarthritis. Since osteochondromatosis activates ectopic chondrogenesis in the synovial membrane, procollagen II C peptide is expected to be a good marker of the disease. Procollagen II C peptide can be used to evaluate the condition of the disease metabolically by simply aspirating the joint fluid. We have experienced a case of osteochondromatosis (Miligram's stage 2) with a high concentration of procollagen II C peptide. This case suggests that the concentration of procollagen II C peptide is a good marker of chondrogenesis by osteochondromatosis.


Asunto(s)
Condromatosis Sinovial/metabolismo , Fragmentos de Péptidos/análisis , Procolágeno/análisis , Líquido Sinovial/metabolismo , Adulto , Condromatosis Sinovial/diagnóstico , Humanos , Masculino
20.
J Long Term Eff Med Implants ; 13(4): 355-62, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14649573

RESUMEN

The Leeds-Keio artificial ligament (LK), which was developed not only as a ligament substitute but also as a scaffold for tissue induction in knee ligament reconstruction, has been in clinical use since 1982 in Europe and Japan. Recently, we have developed radio frequency generated glow discharge (RFGD)-treated LK ligament (Bio-LK) to expedite the process of tissue induction and its maturation. In this study of cell adhesion to the scaffold, we report the difference in the covered area with synovial cells when using scaffolds made from treated and untreated materials. Plasma clot methods were used in this study. The covered area on LK and Bio-LK by cells was stained by 0.1% toluidine blue and analyzed using NIH image. The covered area of Bio-LK was about three times higher than that of LK (untreated) at 3 weeks. In scanning electron microscopy, more cells were observed on fibers of Bio-LK, and these filled the space among the fibers more extensively. The spreading of covered area means that cell attachment, cell proliferation, and cell migration on the fibers are likely to be improved. Our experimental study indicates that Bio-LK will possibly speed up the process of induction of autogenous tissue from synovium.


Asunto(s)
Cápsula Articular/diagnóstico por imagen , Procedimientos Ortopédicos/instrumentación , Ligamento Rotuliano , Prótesis e Implantes , Técnicas de Cultivo de Célula , Humanos , Cápsula Articular/patología , Ligamento Rotuliano/cirugía , Radiografía
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