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1.
Phys Rev Lett ; 125(2): 027201, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32701305

RESUMEN

We measure the mode-resolved direction of the precessional motion of the magnetic order, i.e., magnon polarization, via the chiral term of inelastic polarized neutron scattering spectra. The magnon polarization is a unique and unambiguous signature of magnets and is important in spintronics, affecting thermodynamic properties such as the magnitude and sign of the spin Seebeck effect. However, it has never been directly measured in any material until this work. The observation of both signs of magnon polarization in Y_{3}Fe_{5}O_{12} also gives direct proof of its ferrimagnetic nature. The experiments agree very well with atomistic simulations of the scattering cross section.

2.
Phys Rev Lett ; 117(4): 047201, 2016 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-27494497

RESUMEN

The correlation between magnetic and dielectric properties has been investigated for the single crystal of the chiral triangular-lattice helimagnet MnSb_{2}O_{6}. We found that the spin-spiral plane in the ground state has a considerable tilting from the (110) plane and that the sign of the spin-spiral tilting angle is coupled to the clockwise or counterclockwise manner of spin rotation and accordingly to the sign of magnetically induced electric polarization. This leads to unique magnetoelectric responses such as the magnetic-field-induced selection of a single ferroelectric domain as well as the reversal of electric polarization just by a slight tilting of the magnetic field direction, where the chiral nature of the crystal structure plays a crucial role through the coupling of the chirality between the crystal and magnetic structures. Our results demonstrate that crystallographic chirality can be an abundant source of novel magnetoelectric functions with coupled internal degrees of freedom.

3.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 80(Pt 5): 393-400, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39320309

RESUMEN

Magnetic structures of the noncentrosymmetric magnet Sr2MnSi2O7 were examined through neutron diffraction for powder and single-crystalline samples, as well as magnetometry measurements. All allowed magnetic structures for space group P421m with the magnetic wavevector qm = (0, 0, ½) were refined via irreducible representation and magnetic space group analyses. The compound was refined to have in-plane magnetic moments within the magnetic space group Cmc21.1'c (No. 36.177) under zero field, which can be altered to P212121.1'c (No. 19.28) above µ0H = 0.067 (5) T to align induced weak-ferromagnetic components within one layer on the ab plane. All refined parameters are provided following the recent framework based upon the magnetic space group, which better conveys when exchanging crystallographic information for commensurate magnetic structures.

4.
Opt Express ; 19(20): 19562-71, 2011 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-21996897

RESUMEN

We discuss our estimates of the performance of a superconducting single photon detector (SSPD) in a high speed quantum key distribution (QKD) system. We find that at high repetition operation reflections from the readout circuit at room temperature causes an afterpulse-like phenomenon, and drastically increases the quantum bit error rate (QBER). Such effects are not seen during low frequency operation. By using an amplifier with a small reflection coefficient S11, we succeed in reducing the afterpulse-like phenomenon and increasing a secure key rate.


Asunto(s)
Amplificadores Electrónicos , Tecnología de Fibra Óptica , Fotones , Teoría Cuántica , Procesamiento de Señales Asistido por Computador/instrumentación , Telecomunicaciones/instrumentación , Simulación por Computador , Diseño de Equipo
5.
Opt Express ; 19(21): 20531-41, 2011 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-21997060

RESUMEN

An efficient and low-noise 1.244-GHz gating InGaAs single-photon avalanche photodiode (SAPD) was developed for a high-speed quantum key distribution (QKD) system. An afterpulsing probability of 0.61% and a dark count probability per gate of 0.71 ×10-6 were obtained at a detection efficiency of 10.9% for 1.55-µm photons. Furthermore, our SAPD successfully coped with high detection efficiency (≤ 25%) and quite low afterpulsing noise (≤ 3% for ≤ 25% efficiency) at the same time. Its potential was verified using the actual QKD setups installed over a metropolitan area network.

6.
Opt Express ; 19(11): 10387-409, 2011 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-21643295

RESUMEN

A secure communication network with quantum key distribution in a metropolitan area is reported. Six different QKD systems are integrated into a mesh-type network. GHz-clocked QKD links enable us to demonstrate the world-first secure TV conferencing over a distance of 45km. The network includes a commercial QKD product for long-term stable operation, and application interface to secure mobile phones. Detection of an eavesdropper, rerouting into a secure path, and key relay via trusted nodes are demonstrated in this network.

7.
Sci Adv ; 7(7)2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33579703

RESUMEN

Uterine sensitization-associated gene-1 (USAG-1) deficiency leads to enhanced bone morphogenetic protein (BMP) signaling, leading to supernumerary teeth formation. Furthermore, antibodies interfering with binding of USAG-1 to BMP, but not lipoprotein receptor-related protein 5/6 (LRP5/6), accelerate tooth development. Since USAG-1 inhibits Wnt and BMP signals, the essential factors for tooth development, via direct binding to BMP and Wnt coreceptor LRP5/6, we hypothesized that USAG-1 plays key regulatory roles in suppressing tooth development. However, the involvement of USAG-1 in various types of congenital tooth agenesis remains unknown. Here, we show that blocking USAG-1 function through USAG-1 knockout or anti-USAG-1 antibody administration relieves congenital tooth agenesis caused by various genetic abnormalities in mice. Our results demonstrate that USAG-1 controls the number of teeth by inhibiting development of potential tooth germs in wild-type or mutant mice missing teeth. Anti-USAG-1 antibody administration is, therefore, a promising approach for tooth regeneration therapy.

8.
Br J Cancer ; 103(4): 469-74, 2010 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-20628385

RESUMEN

BACKGROUND: A British randomised study of gemcitabine plus cisplatin (GC) combination showed promising results in biliary tract cancer (BTC) patients. In our study, we evaluated the efficacy and safety of this combination compared with gemcitabine alone (G) in Japanese BTC patients. METHODS: Overall, 84 advanced BTC patients were randomised to either cisplatin 25 mg m(-2) plus gemcitabine 1000 mg m(-2) on days 1, 8 of a 21-day cycle (GC-arm), or single-agent gemcitabine 1000 mg m(-2) on days 1, 8 and 15 of a 28-day cycle (G-arm). Treatments were repeated for at least 12 weeks until disease progression or unacceptable toxicity occurred, up to a maximum of 48 weeks. RESULTS: A total of 83 patients were included in the analysis. For the GC and G-arms, respectively, the 1-year survival rate was 39.0 vs 31.0%, median survival time 11.2 vs 7.7 months, median progression-free survival time 5.8 vs 3.7 months and overall response rate 19.5 vs 11.9%. The most common grade 3 or 4 toxicities (GC-arm/G-arm) were neutropenia (56.1%/38.1%), thrombocytopenia (39.0%/7.1%), leukopenia (29.3%/19.0%), haemoglobin decrease (36.6%/16.7%) and gamma-GTP increase (29.3%/35.7%). CONCLUSIONS: Gemcitabine plus cisplatin combination therapy was found to be effective and well tolerated, suggesting that it could also be a standard regimen for Japanese patients.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias del Sistema Biliar/tratamiento farmacológico , Cisplatino/uso terapéutico , Desoxicitidina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Sistema Biliar/mortalidad , Desoxicitidina/uso terapéutico , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Gemcitabina
9.
Phys Rev Lett ; 105(3): 037402, 2010 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-20867806

RESUMEN

Neutron scattering is used to investigate spin correlations in ultrapure single crystals of the S=1 triangular lattice NiGa(2)S(4). Despite a Curie-Weiss temperature of Θ(CW)=-80(2) K, static (τ>1 ns) short-range (ξ(ab)=26(3) Å) incommensurate order prevails for T>1.5 K. The incommensurate modulation Q(0)=(0.155(3),0.155(3),0), Θ(CW), and the spin-wave velocity (c=4400 m/s) can be accounted for by antiferromagnetic third-nearest-neighbor interactions J(3)=2.8(6) meV and ferromagnetic nearest-neighbor coupling J(1)=-0.35(9) J(3). Interplane correlations are limited to nearest neighbors and weakened by an in-plane field. These observations show that the short-range ordered glassy phase that has been observed in a number of highly degenerate systems can persist near the clean limit.

10.
Sci Rep ; 10(1): 22109, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33335175

RESUMEN

Ti2O3 exhibits unique metal-insulator transition (MIT) at ~ 450 K over a wide temperature range of ~ 150 K. The close relationship between MIT and crystal deformation has been proposed. However, as physical properties are governed by the thermodynamic equilibrium in bulk systems, conducting experimental studies under different lattice deformations remains challenging. Epitaxial thin films can offer high flexibility to accommodate adaptive crystal lattices and provide efficient platforms for investigating the MIT. In this study, we report the synthesis of corundum-type Ti2O3 films on various growth temperatures. We found that the metallic ground states appeared in the films grown at low temperatures. The electronic ground states were further investigated by the electronic-structure calculations. Results suggest that the electrical properties of Ti2O3 films were governed by the c/a ratio of the crystal structure, and the absence of the MIT was attributed to the lattice deformation characterized by an elongated c lattice constant.

11.
Commun Phys ; 2(1)2019.
Artículo en Inglés | MEDLINE | ID: mdl-38915317

RESUMEN

Topological defects are found ubiquitously in various kinds of matter, such as vortices in type-II superconductors, and magnetic skyrmions in chiral ferromagnets. While knowledge on the static behavior of magnetic skyrmions is accumulating steadily, their dynamics under forced flow is still a widely open issue. Here, we report the deformation of the moving magnetic skyrmion lattice in MnSi under electric current flow observed using small-angle neutron scattering. A spatially inhomogeneous rotation of the skyrmion lattice, with an inverse rotation sense for opposite sample edges, is observed for current densities greater than a threshold value j t ~ 1 MA m-2 (106 A m-2). Our result show that skyrmion lattices under current flow experience significant friction near the sample edges due to pinning, this being a critical effect that must be considered for anticipated skyrmion-based applications at the nanoscale.

12.
J Clin Invest ; 101(5): 1102-10, 1998 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9486981

RESUMEN

The Fas receptor and ligand initiate an apoptotic pathway. Alterations in this pathway within tumor cells can result in escape from apoptosis and immune surveillance. We evaluated Fas protein expression in 42 primary pulmonary adenocarcinomas, and Fas expression and function in the lung adenocarcinoma cell lines A549 and A427. Immunohistochemical analysis demonstrated Fas protein expression in 47.6% of the tumors; however, Fas-positive tumors demonstrated cytoplasmic staining without cell surface expression. Northern blot analysis indicated that levels of Fas mRNA were similar in Fas protein-positive tumors to levels in normal lung tissue, but were reduced in Fas protein-negative tumors. Soluble form Fas was not detected in the majority of these tumors either by RT-PCR or Western blot analysis. Cell surface Fas protein expression was minimal in A549 and A427 cell lines as determined by flow cytometry. Both cell lines demonstrated Fas mRNA expression by Northern blot analysis and abundant protein expression by Western blot analysis. Transfection of the Fas cDNA derived from A549 cells induced surface Fas protein in COS cells; however, stable transfection of a native Fas cDNA into A549 cells failed to induce surface Fas protein expression. Parental A549 cells and A549 cells transfected with a Fas expression vector were resistant to Fas-mediated apoptosis. Transgenic expression of a FLAG-tagged Fas cDNA in A549 cells, with visualization of the Fas-FLAG protein using confocal microscopy, demonstrated that the Fas-FLAG protein was retained within cytoplasmic portions of the cell and was not translocated to the cell surface. These findings suggest that the Fas protein is reduced or not present on the cell surface in the primary lung tumors and is sequestered within A549 tumorigenic lung cells, and these alterations directly affect the cells resistance to Fas-mediated apoptosis.


Asunto(s)
Adenocarcinoma/inmunología , Adenocarcinoma/metabolismo , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/metabolismo , Receptor fas/metabolismo , Anciano , Animales , Antígenos de Superficie/inmunología , Antígenos de Superficie/metabolismo , Apoptosis/inmunología , Northern Blotting , Southern Blotting , Western Blotting , Células COS , Citoplasma/metabolismo , ADN/genética , ADN/aislamiento & purificación , ADN Complementario , Femenino , Citometría de Flujo , Expresión Génica , Vectores Genéticos , Humanos , Inmunohistoquímica , Masculino , Microscopía Confocal , Persona de Mediana Edad , Oligopéptidos , Péptidos/inmunología , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Transfección , Células Tumorales Cultivadas , Receptor fas/genética , Receptor fas/inmunología
13.
Cancer Res ; 57(24): 5571-8, 1997 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9407969

RESUMEN

This study describes Fas (CD95) expression in Barrett's esophagus, adenocarcinomas of the esophagus, and three esophageal adenocarcinoma cell lines. Immunohistochemical analysis of Barrett's esophagus demonstrated cell surface expression of Fas protein. In contrast, 30.5% of esophageal adenocarcinomas examined by immunohistochemical analysis demonstrated faint cytoplasmic staining, and 69.5% were negative for Fas. Similar levels of Fas mRNA were identified in tumors compared to mRNA levels in esophageal squamous mucosa or Barrett's esophagus. An approximately Mr 48,000 Fas protein was identified by Western blot analysis in tumors that were negative for Fas expression by immunohistochemical analysis. The esophageal adenocarcinoma cell line Seg-1 was negative for Fas expression by immunohistochemical analysis, but Western blot analysis demonstrated abundant, appropriately sized Fas protein. In agreement with the immunohistochemical analysis, flow cytometry of Seg-1 showed minimal amounts of Fas on the cell surface, which correlated with resistance to Fas-mediated apoptosis. No mutations in the Seg-1 Fas coding sequence or exon 1 were identified by sequence analysis. This was confirmed by transient transfection of COS cells with expression vectors generated from the Seg-1 Fas cDNA, which resulted in cell surface expression of the Fas protein. Stable transfection of Seg-1 with a Fas expression vector did not result in efficient Fas expression on the cell surface. Seg-1 cells, transiently transfected with a Fas-FLAG expression vector and examined for protein expression using confocal microscopy and an anti-FLAG antibody, showed that the Fas-FLAG protein was not present on the cell surface but was present in the cytoplasm. Taken together, these results indicate that expression of Fas on the cell surface by esophageal adenocarcinoma is reduced. In an esophageal adenocarcinoma cell line, wild-type Fas protein is retained in the cytoplasm, and this correlates with resistance to Fas-mediated apoptosis. The retention of wild-type Fas protein within the cytoplasm may represent a mechanism by which malignant cells evade Fas-mediated apoptosis.


Asunto(s)
Adenocarcinoma/metabolismo , Neoplasias Esofágicas/metabolismo , Receptor fas/metabolismo , Adenocarcinoma/patología , Animales , Apoptosis/fisiología , Esófago de Barrett/complicaciones , Esófago de Barrett/metabolismo , Southern Blotting , Células COS/metabolismo , Membrana Celular/metabolismo , ADN/análisis , ADN/genética , ADN de Neoplasias/análisis , ADN de Neoplasias/genética , Epitelio/metabolismo , Neoplasias Esofágicas/patología , Humanos , Inmunohistoquímica , Factores de Riesgo , Células Tumorales Cultivadas , Receptor fas/biosíntesis , Receptor fas/genética
14.
Transplantation ; 69(9): 1785-93, 2000 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10830212

RESUMEN

BACKGROUND: Because the fluid transport capacity of the alveolar epithelium after lung ischemia with and without lung deflation has not been well studied, we carried out experimental studies to determine the effect of lung deflation on alveolar fluid clearance. METHODS: After 1 or 2 hr of ischemia, we measured alveolar fluid clearance using 125I-albumin and Evans blue-labeled albumin concentrations in in vivo rabbit lungs in the presence of pulmonary blood flow and in ex vivo rat lungs in the absence of any pulmonary perfusion, respectively. RESULTS: The principal results were: (1) lung deflation decreased alveolar fluid clearance while inflation of the lungs during ischemia preserved alveolar fluid clearance in both in vivo and ex vivo studies; (2) alveolar fluid clearance was normal in the rat lungs inflated with nitrogen (thus, alveolar gas composition did not affect alveolar fluid clearance); (3) amiloride-dependent alveolar fluid clearance was preserved when the lungs were inflated during ischemia; (4) terbutaline-simulated alveolar fluid clearance was preserved in the hypoxic rat lungs inflated with nitrogen; (5) lecithinized superoxide dismutase, a scavenger of superoxide anion, and N(omega)-nitro-L-arginine methyl ester, an inhibitor of nitric oxide, preserved normal alveolar fluid clearance in the deflated rat lungs. CONCLUSION: Lung deflation decreases alveolar fluid clearance by superoxide anion- and nitric oxide-dependent mechanisms.


Asunto(s)
Isquemia/metabolismo , Pulmón/irrigación sanguínea , Alveolos Pulmonares/metabolismo , Amilorida/farmacología , Animales , Transporte Biológico , Epitelio/metabolismo , Pulmón/metabolismo , Masculino , NG-Nitroarginina Metil Éster/farmacología , Conejos , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/farmacología , Terbutalina/farmacología
15.
J Nucl Med ; 41(1): 85-92, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10647609

RESUMEN

UNLABELLED: The goals of this study were to correlate FDG uptake with cell proliferation and cellular density in non-small cell lung cancer. METHODS: Thirty-one patients with 32 non-small cell lung cancers were examined with FDG PET. For semiquantitative analysis, standardized uptake values (SUVs) were calculated. All patients underwent thoracotomy within 4 wk after the FDG PET study. Cell proliferation was immunohistochemically assessed as the relative number of cells expressing the proliferating cell nuclear antigen ([PCNA] labeling index). Cellular density was also evaluated using light microscopy. RESULTS: SUVs correlated significantly with PCNA labeling index (r = 0.740; P < 0.0001) but only weakly with cellular density (r = 0.392; P = 0.0266). High FDG uptake correlated with high PCNA expression. The PCNA labeling index and SUVs were significantly lower in bronchioloalveolar carcinomas (n = 8) (12.3 +/- 9.45% and 1.45 +/- 0.76, respectively) than in nonbronchioloalveolar carcinomas (n = 19) (33.5 +/- 21.8%, P = 0.015, and 3.75 +/- 1.93, P = 0.003, respectively). However, no significant differences in cellular density were seen between bronchioloalveolar carcinomas and nonbronchioloalveolar carcinomas. CONCLUSION: FDG uptake is related to cell proliferation rather than to the cellular density of non-small cell lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Radiofármacos , Tomografía Computarizada de Emisión , Carcinoma de Pulmón de Células no Pequeñas/patología , División Celular , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Antígeno Nuclear de Célula en Proliferación/análisis
16.
J Nucl Med ; 39(1): 9-15, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9443730

RESUMEN

UNLABELLED: We compared the diagnostic value of [18F]2-fluoro-2-deoxy-D-glucose (FDG) PET imaging and 201Tl SPECT imaging in the detection of primary lung cancer and mediastinal lymph node metastases. METHODS: Thirty-three patients with histologically-proven primary lung cancer were examined with both FDG PET and TI SPECT (early and delayed scans) within a week of each study. For semiquantitative analysis, the tumor-to-nontumor activity ratio (T-to-N ratio) was calculated. RESULTS: Although both techniques delineated focal lesions with an increase in tracer accumulation in 28 patients, PET identified three additional patients in whom Tl SPECT images did not visualize any lesions on both early and delayed scans. In the detection of lung cancer of less than 2 cm in size, FDG PET provided higher sensitivity (six of seven, 85.7%) than did Tl SPECT early scan (one of seven, 14.3%) and delayed scan (four of seven, 57.1%). Neither technique visualized any lesions in two patients who had bronchioloalveolar carcinoma. The T-to-N ratio was significantly higher with FDG PET (10.39 +/- 6.63) than it was with Tl SPECT (early scan, 2.37 +/- 0.86; delayed scan, 3.01 +/- 1.01) (p < 0.0001), whereas there was significant positive correlation between the FDG T-to-N ratio and the thallium T-to-N ratio (p < 0.01). Twenty-two patients had thoracotomies. Regarding the staging of mediastinal nodes, FDG PET detected mediastinal lymph node metastasis that was negative on Tl SPECT, whereas both techniques excluded tumor involvement in enlarged node at CT. CONCLUSION: Both techniques have clinical value for the noninvasive detection of primary lung cancer that is 2 cm or greater in diameter. However, if a PET camera is available, FDG PET is considered the method of choice for the evaluation of patients with suspected primary lung cancer that is less than 2 cm in diameter.


Asunto(s)
Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Radiofármacos , Radioisótopos de Talio , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada de Emisión , Adenocarcinoma/diagnóstico por imagen , Anciano , Carcinoma de Células Escamosas/diagnóstico por imagen , Femenino , Humanos , Neoplasias Pulmonares/patología , Ganglios Linfáticos/diagnóstico por imagen , Metástasis Linfática , Masculino , Mediastino , Sensibilidad y Especificidad
17.
J Appl Physiol (1985) ; 90(1): 10-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11133887

RESUMEN

The effect of denopamine, a selective beta(1)-adrenergic agonist, on alveolar fluid clearance was determined in both ex vivo rat and guinea pig lungs. Alveolar fluid clearance was measured by the progressive increase in the concentration of Evans blue-labeled albumin over 1 h at 37 degrees C. Denopamine (10(-6) to 10(-3) M) increased alveolar fluid clearance in a dose-dependent manner in ex vivo rat lungs. Denopamine also stimulated alveolar fluid clearance in guinea pig lungs. Atenolol, a selective beta(1)-adrenergic antagonist, and amiloride, a sodium channel inhibitor, inhibited denopamine-stimulated alveolar fluid clearance. The potency of denopamine was similar to that of similar doses of isoproterenol or terbutaline. Short-term hypoxia (100% nitrogen for 1-2 h) did not alter the stimulatory effect of denopamine. Denopamine (10(-4), 10(-3) M) increased intracellular adenosine 3',5'-cyclic monophosphate levels in cultured rat alveolar type II cells. In summary, denopamine, a selective beta(1)-adrenergic agonist, stimulates alveolar fluid clearance in both ex vivo rat and guinea pig lungs.


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Líquidos Corporales/metabolismo , Etanolaminas/farmacología , Alveolos Pulmonares/metabolismo , Enfermedad Aguda , Antagonistas Adrenérgicos beta/farmacología , Animales , Células Cultivadas , AMP Cíclico/metabolismo , Cobayas , Hipoxia/metabolismo , Técnicas In Vitro , Isoproterenol/farmacología , Enfermedades Pulmonares/metabolismo , Masculino , Alveolos Pulmonares/citología , Ratas , Ratas Sprague-Dawley , Bloqueadores de los Canales de Sodio , Terbutalina/farmacología
18.
J Appl Physiol (1985) ; 91(4): 1766-74, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11568161

RESUMEN

There is little information regarding the effect of hypoxia on alveolar fluid clearance capacity. We measured alveolar fluid clearance, lung water volume, plasma catecholamine concentrations, and serum osmolality in rats exposed to 10% oxygen for up to 120 h and explored the mechanisms responsible for the increase in alveolar fluid clearance. The principal results were 1) alveolar fluid clearance did not change for 48 h and then increased between 72 and 120 h of exposure to hypoxia; 2) although nutritional impairment during hypoxia decreased basal alveolar fluid clearance, endogenous norepinephrine increased net alveolar fluid clearance; 3) the changes of lung water volume and serum osmolality were not associated with those of alveolar fluid clearance; 4) an administration of beta-adrenergic agonists further increased alveolar fluid clearance; and 5) alveolar fluid clearance returned to normal within 24 h of reoxygenation after hypoxia. In conclusion, alveolar epithelial fluid transport capacity increases in rats exposed to hypoxia. It is likely that a combination of endogenous norepinephrine and nutritional impairment regulates alveolar fluid clearance under hypoxic conditions.


Asunto(s)
Hipoxia/metabolismo , Pulmón/metabolismo , Alveolos Pulmonares/metabolismo , Antagonistas Adrenérgicos alfa/farmacología , Agonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/farmacología , Algoritmos , Animales , Transporte Biológico Activo/efectos de los fármacos , Líquidos Corporales/efectos de los fármacos , Líquidos Corporales/metabolismo , Catecolaminas/sangre , Agua Pulmonar Extravascular/efectos de los fármacos , Agua Pulmonar Extravascular/metabolismo , Privación de Alimentos/fisiología , Pulmón/efectos de los fármacos , Alveolos Pulmonares/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Bloqueadores de los Canales de Sodio/farmacología
19.
Nucl Med Commun ; 21(8): 707-14, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11039452

RESUMEN

2-[Fluorine-18]fluoro-2-deoxy-d-glucose (FDG) uptake within the primary lesion correlates with survival on positron emission tomography (PET) studies of patients with non-small cell lung cancer. The more metabolically active the tumour, the worse the outcome. The aim of this study was to determine whether a correlation exists between aggressiveness as determined by pathology and the findings of FDG PET in pulmonary adenocarcinoma. Thirty-five patients with 38 adenocarcinomas of the lung were studied. All patients underwent thoracotomy within 4 weeks of the FDG PET study. For semiquantitative analysis, standardized uptake values (SUVs) were calculated. Patients were classified into high SUV (> or = 4.0) and low SUV (<4.0) groups. The degree of FDG uptake (SUVs) in primary lung lesions was correlated with the histopathological features of aggressiveness (pleural involvement, vascular invasion or lymphatic permeation). The mean SUV of aggressive adenocarcinomas (4.36+/-1.94, n = 22) was higher than that of non-aggressive ones (1.53+/-0.88, n = 16) (P < 0.0001). Tumours with a high FDG uptake have a significantly higher likelihood of aggressiveness than those with a low FDG uptake (P = 0.0004). Analysis by the Kaplan-Meier methods revealed that the groups had different prognoses (log-rank test, P = 0.0099). The high SUV group had a significantly worse prognosis. In conclusion, a correlation was seen between aggressiveness as determined by pathology and glucose metabolism as measured by FDG PET in adenocarcinoma of the lung. FDG PET may be used as a non-invasive diagnostic technique in measuring aggressiveness and prognosis in patients with pulmonary adenocarcinoma.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Radiofármacos , Adenocarcinoma/metabolismo , Adenocarcinoma Bronquioloalveolar/diagnóstico por imagen , Adenocarcinoma Bronquioloalveolar/metabolismo , Adenocarcinoma Bronquioloalveolar/patología , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Glucosa/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Persona de Mediana Edad , Cintigrafía , Análisis de Supervivencia
20.
No Shinkei Geka ; 17(5): 495-9, 1989 May.
Artículo en Japonés | MEDLINE | ID: mdl-2550831

RESUMEN

A rare case is reported of pineal metastasis from lung cancer initially caused by neurological abnormalities of pineal tumor. A 70-year-old female suffering from headache and deterioration of consciousness for 1 week was admitted. She also had a tumor on both sides of her neck. On admission, neurological examination revealed disturbance of upward gaze, and CT scans showed hydrocephalus and pineal tumor. The tumor was seen as a slightly high density mass on non-contrast CT, and was homogeneously enhanced after administration of contrast material. Right V-P shunt and excision of the left neck tumor were performed at the same time. Pathological diagnosis of neck tumor was undifferentiated carcinoma metastasized to cervical lymph nodes. Extensive study was made, by bronchial fiberscope and biopsy, in order to find the origin of the malignancy and disclosed a small cell lung cancer of left lower lobe. The patient took radiation therapy for both the whole brain (60 Gy) and for the bilateral cervical regions (45 Gy). Two courses of chemotherapy using CDDP, ADR, VCR and CY were administered. Both the neck and the pineal tumors were markedly reduced in size at the termination of radiation therapy. However, she was readmitted 3 months later because of dyspnea. Chest X-P revealed enlargement of the left-lung tumor. She died on April 22, 1987. General autopsy disclosed invasive enlargement of left lung cancer, however, no remote metastasis was found. Examination of pineal region showed only necrotic pineal tissue, and no tumor cell was seen in either macroscopic or microscopic study.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Neoplasias Encefálicas/secundario , Carcinoma de Células Pequeñas/secundario , Neoplasias Pulmonares/patología , Enfermedades del Sistema Nervioso/etiología , Glándula Pineal , Anciano , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Carcinoma de Células Pequeñas/patología , Carcinoma de Células Pequeñas/terapia , Terapia Combinada , Femenino , Humanos , Neoplasias Pulmonares/terapia , Ganglios Linfáticos/patología , Metástasis Linfática , Cuello
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