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1.
Nat Commun ; 8: 14467, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28211544

RESUMEN

Controlled access to the border of the Mott insulating state by variation of control parameters offers exotic electronic states such as anomalous and possibly high-transition-temperature (Tc) superconductivity. The alkali-doped fullerides show a transition from a Mott insulator to a superconductor for the first time in three-dimensional materials, but the impact of dimensionality and electron correlation on superconducting properties has remained unclear. Here we show that, near the Mott insulating phase, the upper critical field Hc2 of the fulleride superconductors reaches values as high as ∼90 T-the highest among cubic crystals. This is accompanied by a crossover from weak- to strong-coupling superconductivity and appears upon entering the metallic state with the dynamical Jahn-Teller effect as the Mott transition is approached. These results suggest that the cooperative interplay between molecular electronic structure and strong electron correlations plays a key role in realizing robust superconductivity with high-Tc and high-Hc2.

2.
Phys Rev Lett ; 101(13): 136404, 2008 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-18851470

RESUMEN

Superconductivity emerges for the A15 polymorph of the fulleride Cs3C60 upon compression to a pressure of approximately 4 kbar. Using density functional theory we study the bonding in the A15 phase as a function of unit cell volume comparing it to that in the fcc polymorph. We find that, despite its smaller packing density, the bcc-derived A15 phase has both a substantially wider bandwidth for the partially occupied t1u band and a higher density of states at the Fermi level. This result can be traced to the striking differences in the nature of the interanion Tc--the two sphere packings (body centered versus face centered) observed experimentally produce two electronically distinct classes of fulleride superconductors.

3.
Langmuir ; 22(26): 10989-93, 2006 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-17154575

RESUMEN

A well-defined, double-hydrophilic diblock copolymer comprising poly[2-(methacryloyloxy)ethyl phosphorylcholine]-block-(glycerol monomethacrylate) (PMPC30-PGMA30, where the numbers represent the average degrees of polymerization for each block) was evaluated for the synthesis of colloidally stable ultrafine magnetite sols. Sterically stabilized paramagnetic sols were prepared in aqueous solution by chemical coprecipitation of ferric and ferrous salts in the presence of this block copolymer. The PMPC30-PGMA30-stabilized magnetite sol had a mean transmission electron microscopy (TEM) diameter of 9.4 +/- 1.7 nm and a mean hydrodynamic diameter of 34 nm. This sol exhibited improved colloidal stability with respect to long-term storage and pH variation compared with magnetite sols prepared in the presence of alternative water-soluble homopolymers and diblock copolymers. Fourier transform infrared (FT-IR) spectroscopy, thermogravimetry, electron spectroscopy imaging (ESI), and zeta potential studies indicate that the PMPC30-PGMA30 diblock copolymer was adsorbed onto the surface of the sol via the PGMA30 block, with the PMPC30 chains acting as the stabilizing block. Such sterically stabilized sols are expected to be improved contrast agents for magnetic resonance imaging (MRI) applications.


Asunto(s)
Materiales Biocompatibles Revestidos/síntesis química , Medios de Contraste/síntesis química , Óxido Ferrosoférrico/síntesis química , Metacrilatos/síntesis química , Nanopartículas/química , Fosforilcolina/análogos & derivados , Materiales Biocompatibles Revestidos/química , Medios de Contraste/química , Óxido Ferrosoférrico/química , Imagen por Resonancia Magnética/métodos , Metacrilatos/química , Microscopía Electrónica de Transmisión , Nanopartículas/ultraestructura , Fosforilcolina/síntesis química , Fosforilcolina/química , Ácidos Polimetacrílicos
4.
Phys Rev Lett ; 97(14): 145502, 2006 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-17155267

RESUMEN

We have measured deexcitation x rays emitted from the resonant coherently excited 2(1)P(1) state of heliumlike Fe24+ ions of 423 MeV/amu, planar channeling through a Si crystal. Large anisotropy in the angular distribution of deexcitation x-ray emission is observed: the x-ray emission in the direction parallel to the channeling plane is favored by a factor of 2 compared to the perpendicular direction. This anisotropy originates from the direction of the periodic crystal field, which populates specific m states in resonant coherent excitation and aligns the excited states.

5.
J Synchrotron Radiat ; 8(Pt 2): 551-3, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11512848

RESUMEN

Structure of metal endohedral fullerenes is studied by XAFS and XANES. The Sc-Sc distance of 2.23(1) A determined from Sc K-edge XAFS supports the formation of a triangular Sc3 cluster in Sc3@C82 as is found by MEM analysis for the X-ray diffraction. Gd L(III)-edge XAFS of Gd@C82 shows that the first and the second neigboring Gd-C distances are 2.51(2) and 2.85(4) A, respectively. The La-La distance of La2@C80 has been determined to be 3.90(1) A at 40 K. This value does not change when increasing temperature [3.90(2) A at 240 K]. The position and the valenece of the Eu atom in Eu@C60 are also discussed based on Eu L(III)-edge XAFS and XANES.

6.
J Synchrotron Radiat ; 8(Pt 2): 725-7, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11512910

RESUMEN

Cs K-edge XAFS of Cs3C60 which is a pressure-induced superconductor were measured at 21 and 34 kbar by using a diamond anvil cell (DAC) in order to obtain the structural information under high pressure, and to clarify the origin of the pressure-induced superconductivity. The distances and the mean square displacements between the Cs and C atoms are consistent with those determined by X-ray powder diffraction. Consequently, the high-pressure XAFS can give the reliable structural-information on a fullerene superconductor under high pressure. We also show the procedure of the analysis of high-pressure XAFS with DAC in detail.

7.
Nihon Kokyuki Gakkai Zasshi ; 39(4): 250-5, 2001 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-11481823

RESUMEN

We encountered two cases of perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA). The first was a case of idiopathic interstitial pneumonia diagnosed in a 73-year-old man since 1998. He was admitted to our hospital because of renal failure and anemia. The serum level of p-ANCA on admission was 264 EU, and specimens obtained by percutaneous renal biopsy showed crescentic glomerulonephritis and vasculitis due to p-ANCA. He was treated with prednisolone pulse therapy and prednisolone (PSL), however interstitial pneumonia occurred during PSL tapering. We treated him for pulmonary fibrosis with plasmapheresis, methylprednisolone (mPSL) and cyclophosphamide (CPA), which suppressed the progress of the interstitial pneumonia. The second case was one of massive pulmonary hemorrhage in a 68-year-old man who was admitted to our hospital. Physical examination revealed anemia: the laboratory data, renal failure; and the serum level of p-ANCA was elevated to 611 EU. The specimens obtained by percutaneous renal biopsy showed crescentic glomerulonephritis and vasculitis. The renal failure was not improved by PSL, but, together with the inflammation, responded to the combination of PSL and CPA. However, both patients died of serious infection. They were regarded as compromised patients because of the therapy mentioned above. No standard therapy has been established against p-ANCA positive pulmonary disease with renal failure. The treatment should control the progression of interstitial pneumonitis and pulmonary hemorrhage. It is important to consider the possibility of serious infection.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/análisis , Glomerulonefritis/inmunología , Enfermedades Pulmonares Intersticiales/inmunología , Anciano , Ciclofosfamida/administración & dosificación , Quimioterapia Combinada , Glomerulonefritis/complicaciones , Glomerulonefritis/tratamiento farmacológico , Humanos , Enfermedades Pulmonares Intersticiales/complicaciones , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Masculino , Prednisolona/administración & dosificación , Quimioterapia por Pulso
8.
Amyloid ; 6(4): 292-6, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10611952

RESUMEN

A 67-year-old female patient with biopsy proven AL systemic amyloidosis developed rapidly progressive dyspnea. Chest roentgenogram and CT scan revealed a large right pleural effusion in addition to nodular lesions with bilateral hilar lymphadenopathy. The patient's serum showed IgG lambda type monoclonal gammopathy and she also had Bence Jones proteinuria. The pleural effusion was an exudate that contained many mononuclear cells and a high concentration of protein. Cardiac function was not seriously disturbed. Except for amyloidosis, no other causes for the severe pleural effusion were found. This patient was treated with chemical pleurodesis using Picibanil and a low dose of prednisolone. Eighteen months after this treatment, her right pleural effusion did not recur. Bronchopulmonary tissues are known to be frequently involved by AL systemic amyloidosis, but a nodular pattern of pulmonary amyloid deposition and a unilateral large pleural effusion are rare clinical manifestations in this disease.


Asunto(s)
Amiloidosis/complicaciones , Enfermedades Pulmonares/etiología , Derrame Pleural/etiología , Anciano , Amiloide/análisis , Amiloidosis/diagnóstico por imagen , Femenino , Histocitoquímica , Humanos , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/patología , Picibanil/uso terapéutico , Derrame Pleural/tratamiento farmacológico , Derrame Pleural/patología , Prednisolona/uso terapéutico , Radiografía
9.
Respiration ; 66(6): 544-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10575342

RESUMEN

A 26-year-old single female was admitted to hospital with recurrent chest pain, cough and hemoptysis. The symptoms developed 5 months before admission coinciding with menstruation. The disease was diagnosed as pulmonary endometriosis. She was treated with a long-acting gonadotropin-releasing hormone analogue (GnRH agonist; sustained-release leuprolide acetate, 3.75 mg/month, i.m.) for 6 months. She remained asymptomatic for 16 months with regular menstruation even after discontinuing the treatment. This indicates that the initial treatment of pulmonary endometriosis with a GnRH agonist is an acceptable medical alternative, especially in patients with a short duration of the disease from the onset of the chest symptoms.


Asunto(s)
Leuprolida/administración & dosificación , Enfermedades Pulmonares/tratamiento farmacológico , Adulto , Preparaciones de Acción Retardada , Esquema de Medicación , Endometriosis , Femenino , Estudios de Seguimiento , Humanos , Enfermedades Pulmonares/diagnóstico , Tomografía Computarizada por Rayos X
11.
Nihon Kokyuki Gakkai Zasshi ; 37(12): 970-3, 1999 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-10707536

RESUMEN

Between 1996 and 1998, we treated 6 patients with unresectable and advanced thymic cancer (stages IVa and IVb). All received 50 mg/m2 of cisplatin and 40 mg/m2 of doxorubicin intravenously (i.v.) on day 1,0.6 mg/m2 of vincristine i.v. on day 3, and 700 mg/m2 of cyclophosphamide i.v. on day 4; ADOC regimen, respectively at 3-4 week intervals. Four patients obtained a partial response (PR) after ADOC chemotherapy and the overall clinical response rate was 67%. No life-threatening side effects were noted. In 2 patients, cisplatin plus VP-16 chemotherapy failed to demonstrate any benefits prior to the ADOC regimen. Radiotherapy was initiated after the achievement of PR in the other 2 patients. ADOC chemotherapy appears to be an effective treatment for thymic cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/terapia , Neoplasias del Timo/terapia , Anciano , Cisplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioterapia Adyuvante , Resultado del Tratamiento , Vincristina/administración & dosificación
13.
J Synchrotron Radiat ; 6(Pt 3): 564-6, 1999 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-15263381
14.
J Am Coll Cardiol ; 29(1): 168-74, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8996310

RESUMEN

OBJECTIVES: This study attempted to assess myocardial sympathetic innervation using iodine-123 (I-123) metaidobenzylguanidine (MIBG) imaging in patients with familial amyloid polyneuropathy. BACKGROUND: Signs and symptoms of cardiac autonomic dysfunction are commonly seen in patients with cardiac amyloidosis. However, the incidence and magnitude of abnormalities in myocardial sympathetic nerve function by means of I-123 MIBG imaging and their relation to clinical findings, cardiac function and the results of thallium-201 (Tl-201) and technetium-99m pyrophosphate (Tc-99m PYP) myocardial scanning have not yet been clarified. METHODS: We performed M-mode, two-dimensional and Doppler echocardiography and I-123 MIBG, Tl-201 and Tc-99m PYP imaging of the heart in 12 patients with familial amyloid polyneuropathy and biopsy-proved cardiac amyloidosis. RESULTS: Ten of 12 patients had no clinical evidence of overt heart disease, but left ventricular (LV) wall thickening was observed in 4 of these 10. Left ventricular percent fractional shortening and Doppler transmitral flow velocity patterns were found to be normal in all 12 patients. Eight of 12 patients showed no myocardial MIBG accumulation, with limited uptake in the remaining 4 demonstrated only in the LV anterior wall. Diffuse but mild myocardial uptake of Tc-99m PYP occurred in only 4 of 12 patients, and all 12 had normal results on Tl-201 myocardial scanning. Complete defects on myocardial MIBG scans were found in five of eight patients with negative findings on Tc-99m PYP myocardial scanning. The incidence and magnitude of myocardial uptake of MIBG were independent of clinical findings, extent of endomyocardial amyloid deposition, electrocardiographic QRS voltage and ventricular wall thickness. CONCLUSIONS: Patients with familial amyloid polyneuropathy show a high incidence of myocardial adrenergic denervation with viable myocardium that can be identified very early in cardiac amyloidosis, before the development of clinically apparent heart disease, ventricular wall thickening, significant LV systolic and diastolic dysfunction and positive findings on Tc-99m PYP myocardial scanning.


Asunto(s)
Neuropatías Amiloides/diagnóstico por imagen , Enfermedades del Sistema Nervioso Autónomo/diagnóstico por imagen , Cardiomiopatías/diagnóstico por imagen , Corazón/diagnóstico por imagen , Radioisótopos de Yodo , Yodobencenos , 3-Yodobencilguanidina , Adulto , Neuropatías Amiloides/diagnóstico , Neuropatías Amiloides/fisiopatología , Enfermedades del Sistema Nervioso Autónomo/diagnóstico , Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Cardiomiopatías/diagnóstico , Cardiomiopatías/fisiopatología , Medios de Contraste , Ecocardiografía , Femenino , Corazón/inervación , Humanos , Masculino , Cintigrafía , Pirofosfato de Tecnecio Tc 99m , Radioisótopos de Talio
15.
Eur Respir J ; 9(9): 1947-9, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8880116

RESUMEN

We present a case of high altitude pulmonary oedema (HAPE) with pulmonary hypertension and polymorphonuclear leucocyte (PMN) accumulation in bronchoalveolar lavage fluid (BALF), which occurred in a 21 year old man. Plasma endothelin-1 (ET-1) and interleukin-8 (IL-8) concentration in BALF were elevated on admission, and returned to normal level at recovery, when the pulmonary artery pressure and the PMN counts in BALF were normal. In addition, E-selectin and intercellular adhesion molecule-1 (ICAM-1) in BALF were also slightly increased on admission. These findings suggest that endothelin-1 is a vasoconstrictor which contributes to the pulmonary hypertension in high altitude pulmonary oedema, and that some of the inflammatory mediators play an important role in chemotaxis and accumulation of polymorphonuclear leucocytes in the development of high altitude pulmonary oedema.


Asunto(s)
Mal de Altura/complicaciones , Endotelina-1/sangre , Interleucina-8/análisis , Edema Pulmonar/metabolismo , Adulto , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Quimiotaxis de Leucocito , Selectina E/análisis , Humanos , Hipertensión Pulmonar/etiología , Molécula 1 de Adhesión Intercelular/análisis , Recuento de Leucocitos , Masculino , Montañismo/lesiones , Neutrófilos/patología , Edema Pulmonar/sangre , Edema Pulmonar/etiología , Presión Esfenoidal Pulmonar , Vasoconstrictores/sangre
16.
Nihon Kyobu Shikkan Gakkai Zasshi ; 31(6): 775-9, 1993 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-8345713

RESUMEN

A 29-year-old male climber developed high altitude pulmonary edema (HAPE), progressing from headache and dyspnea to disturbance of consciousness in the Japan Alps. He was admitted to Shinshu University Hospital. Physical examination on admission revealed a cyanotic patient with coarse crackles and wheezes in bilateral lungs. Chest X-ray film showed bilateral patchy infiltrates. Arterial blood gases indicated severe hypoxemia, and respiratory alkalosis; pH 7.452, PO2 35.5 Torr, PCO2 31.6 Torr. Right heart catheterization showed noncardiogenic pulmonary edema, analysis of bronchoalveolar lavage (BAL) fluid was as follows; cells 2.05 x 10(5)/ml (alveolar macrophages 61.5%, neutrophils 25.5%, lymphocytes 13.0%), protein concentration 91 mg/dl. Cellular and protein analysis of BAL has been shown to be of value to clarify the pathogenesis of the permeability edema in patients with HAPE.


Asunto(s)
Mal de Altura/patología , Líquido del Lavado Bronquioalveolar/citología , Edema Pulmonar/patología , Adulto , Líquido del Lavado Bronquioalveolar/química , Humanos , Masculino
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