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1.
Neoplasma ; 65(6): 915-924, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30334452

RESUMEN

Although platinum-based chemotherapies have long been used as standard treatment in ovarian cancer, cisplatin resistance is a major problem that restricts its use. Herein, we investigate the biological function of SLC27A2 and its underlying mechanisms in regulating chemo-resistance in ovarian cancer. The findings show that SLC27A2 down-regulation in primary ovarian cancer tissues correlates with chemo-resistance and poor patient survival in our patient cohort. Significantly, we demonstrate that up-regulation of SLC27A2 by lentivirus-mediated p-SLC27A2 sensitizes ovarian cancer cells to cisplatin in vitro and in vivo via apoptosis. Mechanistic investigation reveals that miR-411 is the most strikingly over-expressed gene in response to ectopic expression of SLC27A2, but under-expressed in recurrent ovarian cancer tissues. Lower miR-411 expression contributes to ovarian cancer chemo-resistance in vitro and in vivo. Furthermore, SLC27A2 directly binds specific sites in the miR-411 promoter region and promoter activity decreases after mutation of putative SLC27A2-binding sites. This indicates that SLC27A2 is required for the transcriptional induction of miR-411. The luciferase assays also confirm that miR-411 directly targets ABCG2 in ovarian cancer, and overall findings establish the SLC27A2-miR-411-ABCG2 pathway in the regulation of ovarian cancer chemo-resistance with potential therapeutic applications.


Asunto(s)
Antineoplásicos/farmacología , Coenzima A Ligasas/genética , Resistencia a Antineoplásicos , MicroARNs/genética , Neoplasias Ováricas/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Línea Celular Tumoral , Cisplatino , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas de Neoplasias/genética , Recurrencia Local de Neoplasia , Neoplasias Ováricas/tratamiento farmacológico
3.
Science ; 369(6500): 184-188, 2020 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-32646999

RESUMEN

Tuning a semiconductor to function as a fast proton conductor is an emerging strategy in the rapidly developing field of proton ceramic fuel cells (PCFCs). The key challenge for PCFC researchers is to formulate the proton-conducting electrolyte with conductivity above 0.1 siemens per centimeter at low temperatures (300 to 600°C). Here we present a methodology to design an enhanced proton conductor by means of a Na x CoO2/CeO2 semiconductor heterostructure, in which a field-induced metallic state at the interface accelerates proton transport. We developed a PCFC with an ionic conductivity of 0.30 siemens per centimeter and a power output of 1 watt per square centimeter at 520°C. Through our semiconductor heterostructure approach, our results provide insight into the proton transport mechanism, which may also improve ionic transport in other energy applications.

4.
Science ; 370(6513): 179, 2020 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-33033209
5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 20(6): 369-71, 390, 1992 Dec.
Artículo en Zh | MEDLINE | ID: mdl-1307980

RESUMEN

This study is to demonstrate the role of early afterdepolarization (EAD) in the cesium chloride induced long QT interval and ventricular arrhythmias by recording monophasic action potential (MAP) of right ventricular endocardium with contact electrode in 12 closed chest dogs. The results suggested that EAD could produce triggered premature ventricular beats and ventricular tachycardias (VT) in situ. The first ectopic ventricular beat of EAD induced VT usually appears close to the peak of the U wave. Short-long-short interval sequence preceding episodes of VT occurred in 89.6% of VT.


Asunto(s)
Cloruros , Taquicardia Ventricular/fisiopatología , Potenciales de Acción , Animales , Cesio , Perros , Electrocardiografía , Electrofisiología , Endocardio/fisiopatología , Femenino , Masculino , Taquicardia Ventricular/inducido químicamente
6.
IEEE Trans Inf Technol Biomed ; 16(6): 1043-50, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22711780

RESUMEN

This paper presents the prototype implementation of a Bio-Patch using fully integrated low-power System-on-Chip (SoC) sensor and paper-based inkjet printing technology. The SoC sensor is featured with programmable gain and bandwidth to accommodate a variety of bio-signals. It is fabricated in a 0.18-ìm standard CMOS technology, with a total power consumption of 20 ìW from a 1.2 V supply. Both the electrodes and interconnections are implemented by printing conductive nano-particle inks on a flexible photo paper substrate using inkjet printing technology. A Bio-Patch prototype is developed by integrating the SoC sensor, a soft battery, printed electrodes and interconnections on a photo paper substrate. The Bio-Patch can work alone or operate along with other patches to establish a wired network for synchronous multiple-channel bio-signals recording. The measurement results show that electrocardiogram and electromyogram are successfully measured in in-vivo tests using the implemented Bio-Patch prototype.


Asunto(s)
Informática Médica/instrumentación , Sistemas Microelectromecánicos/instrumentación , Monitoreo Fisiológico/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Telemedicina/instrumentación , Electrocardiografía , Electromiografía , Diseño de Equipo , Humanos , Impresión
7.
J Int Med Res ; 40(1): 134-40, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22429353

RESUMEN

OBJECTIVE: This study evaluated serum levels of the neuropeptides calcitonin gene-related peptide (CGRP) and substance P (SP) in coronary artery disease (CAD) patients with and without a history of diabetes mellitus (DM). METHODS: Patients undergoing coronary angiography for suspected myocardial ischaemia were divided into four groups depending on their clinical status: control group (no CAD or DM; n=44), DM group (DM without CAD; n=46), CAD group (stable CAD without DM; n=44) and DM+CAD group (stable CAD with DM; n=50). Serum levels of CGRP and SP were determined using radioimmunoassays. RESULTS: CGRP and SP levels in the DM and CAD groups were significantly lower than in the control group. The lowest levels of CGRP and SP were observed in the DM+CAD group. There were no significant differences in CGRP and SP levels between the DM group and the CAD group. CONCLUSION: CGRP and SP may have a role in the pathogenesis of CAD in patients with diabetes.


Asunto(s)
Calcitonina/sangre , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/complicaciones , Complicaciones de la Diabetes/sangre , Precursores de Proteínas/sangre , Sustancia P/sangre , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Demografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/sangre , Isquemia Miocárdica/complicaciones
8.
J Synchrotron Radiat ; 16(Pt 1): 30-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19096171

RESUMEN

Lattice vibrations have been investigated in TiB2, ZrB2 and HfB2 by temperature-dependent extended X-ray absorption fine structure (EXAFS) experiments. Data clearly show that the EXAFS oscillations are characterized by an anomalous behavior of the Debye-Waller factor of the transition-metal-boron pair, which is suggested to be associated with a superposition of an optical mode corresponding to phonon vibrations induced by the B sublattice and an acoustic mode corresponding to the transition-metal (TM) sublattice. Data can be interpreted as a decoupling of the metal and boron vibrations observed in these transition-metal diborides (TMB2), a mechanism that may be responsible for the significant reduction of the superconducting transition temperature observed in these systems with respect to the parent MgB2 compound. The vibrational behavior of TM-TM bonds has also been investigated to study the occurrence of anisotropy and anomalies in the lattice vibrational behavior of TM-TM bonds.

9.
Pacing Clin Electrophysiol ; 15(11 Pt 2): 2164-8, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1279619

RESUMEN

Torsade de pointes (TdP) syncopal episodes were almost invariably precipitated by emotional stress or menstruation in a 17-year-old girl. U wave accentuation occurred during sinus rhythm without pauses in periods of heightened sympathetic tone. To examine the role of early afterdepolarization (EAD), monophasic action potentials were recorded during ventricular extrasystoles and TdP occurring spontaneously and induced by ventricular pacing. The effects of lidocaine, verapamil, propranolol, and epinephrine were assessed. Our data show that: (1) EAD plays a significant role in the genesis of familial long QTU syndrome and TdP; (2) rapid ventricular pacing causes postpause-dependent EADs, U waves, and TdP; and (3) EAD is enhanced by epinephrine infusion in the absence of pause, whereas EAD-triggered firing is inhibited by verapamil and propranolol but not by lidocaine.


Asunto(s)
Sistema de Conducción Cardíaco/fisiopatología , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/fisiopatología , Torsades de Pointes/fisiopatología , Potenciales de Acción/fisiología , Adolescente , Estimulación Cardíaca Artificial , Epinefrina/farmacología , Femenino , Humanos , Lidocaína/farmacología , Síndrome de QT Prolongado/diagnóstico , Menstruación , Propranolol/farmacología , Estrés Psicológico/complicaciones , Síncope/etiología , Verapamilo/farmacología
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