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1.
Chemistry ; 30(21): e202304328, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38332328

RESUMEN

Although λ5-phosphinine derivatives are known as a promising class of blue fluorescent emitters, those photoluminescent quantum yield (PLQY) values have been reached up to 92 %, however, only a few examples have been explored as an emitter for blue organic light-emitting device (OLED), and the external quantum efficiency (EQE) has been below 2.4 % so far. In this study, we newly developed two types of blue λ5-phosphinine derivatives namely CN-COCF3 and CO2Me-CHO, and investigated the photophysical properties in the solid states. The photophysical analyses in solid state films suggested that the strong electron-accepting nature of these λ5-phosphinine derivatives caused the inferior PLQY values, and the exciplex formation with the host and neighboring materials should be avoided to improve the device efficiency. By choosing suitable host and neighboring materials with deep ionization potentials, we successfully realized efficient blue fluorescent OLEDs with EQE of over 4 % and CIE (0.14, 0.18). This is among the best in λ5-phosphinine-based blue OLEDs so far.

2.
Chemistry ; 25(65): 14762-14766, 2019 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-31412147

RESUMEN

The selective and efficient removal of oxygenated groups from lignin-derived phenols is a critical challenge to utilize lignin as a source for renewable aromatic chemicals. This report describes how surface modification of a zeolite-supported Pt catalyst using ionic liquids (ILs) remarkably increases selectivity for the hydrodeoxygenation (HDO) of phenols into arenes under mild reaction conditions using atmospheric pressure H2 . Unmodified Pt/H-ZSM-5 converts phenols into aliphatic species as the major products along with a slight amount of arenes (10 % selectivity). In contrast, the catalyst modified with an IL, 1-butyl-3-methylimidazolium triflate, keeps up to 76 % selectivity for arenes even at a nearly complete conversion of phenols. The IL on the surface of Pt catalyst may offer the adsorption of phenols in an edge-to-face manner onto the surface, thus accelerating the HDO without the ring hydrogenation.

3.
J Am Chem Soc ; 140(6): 2046-2049, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29400451

RESUMEN

A practical synthesis of a variety of λ5-phosphinines, which show distinct fluorescence both in solution and solid state, is described. Both C4-selective electrophilic substitutions and the following conversions realized an easy preparation of a wide range of derivatives having several substituents for electronic modification, which provides the potential for fine-tuning of the photophysical properties.

4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3040-3043, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29060539

RESUMEN

This paper presents a swallowable sensor device that can be ingested orally, later passing to the stomach, where the device can indwell for long periods. Using wireless communication, it can be egested at any time after it is triggered. This device can indwell using a silicone balloon in the gastrointestinal tract. A chemical reaction inflates the balloon inside the stomach. Then it is deflated to egest the sensor device using an actuator with electrolysis of water. Energy for the actuator with electrolysis can be fed wirelessly. Near field communication and a flexible antenna are used for power feeding and wireless data communication. Because of the flexible balloon and the flexible antenna, the device size can be minimized without performance degradation.


Asunto(s)
Deglución , Técnicas Biosensibles , Diseño de Equipo , Tracto Gastrointestinal , Tecnología Inalámbrica
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 3035-3038, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28268951

RESUMEN

Various types of implants are being commonly used for monitoring vital signals and controlling the critically ill patient's condition such as arrhythmia, sick sinus syndrome, etc. For implanting these medical devices under the skin, surgery is inevitable. These days many patients are more willing to accept interventional therapies that are less invasive, especially inserting a catheter into a blood vessel or endoscopy through a natural orifice. To be able to use interventional therapy for implanting medical devices, they will need to be small enough to fit them through a catheter or the forceps channel of an endoscope. We evaluated a wirelessly powered prototype of a thin coil shaped (diameter 0.05 inches) implant for electrocardiogram (ECG) monitoring and controlling abnormal heart rhythms. An extracorporeal unit fed power to the sensors and transceiver circuit. We are planning to add sensors for detecting ECG signals and also a pulse generator for transmitting signals to the heart. At 13.6MHz, 10mW was wirelessly transferred from the helical antenna attached to the chest wall of the phantom to the coil's receiving antenna and the power enabled the sensors and circuits to work. Moreover, the coil's receiving antennas worked as stimulating electrodes similar to a pacemaker lead.


Asunto(s)
Electrocardiografía/métodos , Monitoreo Fisiológico , Prótesis e Implantes , Diseño de Prótesis , Signos Vitales/fisiología , Tecnología Inalámbrica , Electrodos , Corazón/fisiología , Humanos , Contracción Miocárdica , Marcapaso Artificial , Fantasmas de Imagen
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 3039-3042, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28268952

RESUMEN

This paper presents a swallowable sensor device that can be ingested orally, later arriving to the stomach, where the device can indwell for a long term and can be egested at any time after it is triggered using wireless communication. This device can inflate a silicone balloon in the gastrointestinal tract using a chemical reaction. The balloon can be deflated later using electrolysis of water at the time of egestion. A motorless chemical-reaction-based egestion method is proposed to minimize the sensor device size. This device can achieve long-term monitoring in the gastrointestinal tract.


Asunto(s)
Técnicas Biosensibles/instrumentación , Deglución/fisiología , Tracto Gastrointestinal/fisiología , Monitoreo Fisiológico/instrumentación , Tecnología Inalámbrica/instrumentación , Dióxido de Carbono , Humanos , Bicarbonato de Sodio , Factores de Tiempo
7.
Chem Commun (Camb) ; 51(98): 17382-5, 2015 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-26465096

RESUMEN

N-Heterocyclic carbenes bearing poly(ethylene glycol) chains of different lengths have been designed and employed as ligands in palladium-catalyzed coupling reactions. The catalyst system having longer chains was found to be highly efficient for Suzuki-Miyaura coupling and borylation reactions employing aryl chlorides under mild reaction conditions.


Asunto(s)
Compuestos de Bifenilo/síntesis química , Compuestos de Boro/síntesis química , Paladio/química , Polietilenglicoles/química , Compuestos de Bencilo/síntesis química , Catálisis , Imidazoles/síntesis química , Ligandos , Estructura Molecular , Polietilenglicoles/síntesis química
8.
Chem Commun (Camb) ; 51(95): 17000-3, 2015 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-26446803

RESUMEN

The hydrodeoxygenation of various phenols to form cyclohexanes was achieved at 110 °C under an H2 atmosphere at ambient pressure using a Pt/H-ZSM-5 catalyst and octane as the solvent.

9.
Artículo en Inglés | MEDLINE | ID: mdl-26737193

RESUMEN

Several types of implant devices have been proposed and introduced into healthcare and telemedicine systems for monitoring physiological parameters, sometimes for very long periods of time. To our disappointment, most of the devices are implanted invasively and by surgery. We often have to surgically remove such devices after they have finished their mission or before the battery becomes worn out. Wearable devices have the possibility to become new modalities for monitoring vital parameters less-invasively. However, for round-the-clock monitoring of data from sensors over long periods of time, it would be better to put them inside the body to avoid causing inconvenience to patients in their daily lives. This study tested a less invasive endoluminal approach and innovative tools (developed during our research into therapeutic capsule endoscopy) for remotely anchoring ingestible sensors to the stomach wall. Preliminary investigations are also described about wireless communication (NFC, ZigBee, and Bluetooth) for low power consumption and inductive extracorporeal power feeding wirelessly to the circuits in a phantom lined with swine gastric mucosa. Electrocardiogram and pH were monitored and those parameters were successfully transmitted by wireless communication ICs to the Internet via a portable device.


Asunto(s)
Endoscopía Capsular , Animales , Endoscopios en Cápsulas , Fundus Gástrico , Mucosa Gástrica , Humanos , Concentración de Iones de Hidrógeno , Monitoreo Fisiológico/instrumentación , Fantasmas de Imagen , Teléfono Inteligente , Porcinos , Tecnología Inalámbrica
10.
Chem Commun (Camb) ; 50(81): 12123-6, 2014 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-25177750

RESUMEN

Quatermetallic alloy nanoparticles of Ni/Ru/Pt/Au were prepared and found to promote the catalytic transfer hydrogenation of non-activated alkenes bearing conjugating units (e.g., 4-phenyl-1-butene) with 2-propanol, where the composition metals, Ni, Ru, Pt, and Au, act cooperatively to provide significant catalytic ability.

11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2014: 6997-7000, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25571606

RESUMEN

Ever since capsule endoscopy (CE) was introduced into clinical practice, we gastroenterologists have been dreaming of using this less invasive modality to explore the entire gastrointestinal (GI) tract. To realize this dream, we have developed a magnetic navigation system which includes real-time internet streaming of endoscopic video and some useful gadgets (position detection by means of magnetic impedance (MI) sensors and a modified capsule that is "weightless" in water). The design of the weightless capsule made it possible with 0.5T (Tesla) extracorporeal magnets to control the capsule beyond 20cm. A pair of MI sensors on the body surface could detect subtle magnetic flux generated by an intra-capsular magnet in the GI tract by utilizing the space diversity effect which eliminated the interference of terrestrial magnetism. Subjects underwent CE, during which they were free from confinement in the hospital, except for 1 hour when the capsule was manipulated in the stomach and colon. This study had a completion rate of 97.5%. The high completion rate indicates that our system (single capsule endoscopy-SCE) with further improvements could become a viable modality for screening of the entire GI tract.


Asunto(s)
Endoscopios en Cápsulas , Endoscopía Capsular/instrumentación , Endoscopía Capsular/métodos , Tracto Gastrointestinal/patología , Magnetismo , Diseño de Equipo , Humanos , Internet , Fenómenos Magnéticos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador , Estómago , Agua
12.
Artículo en Inglés | MEDLINE | ID: mdl-25571607

RESUMEN

A few types of steerable capsule endoscopes have been proposed but disappointingly their systems were not applicable to common endoscopic treatment or pathological diagnosis. This study validates the possibility of treatment and biopsy by using an internet-linked (wireless control via the internet) robotic capsule endoscope (iRoboCap). iRoboCap consisted of three parts: an imaging unit, a movement control unit and a therapeutic tool unit. Two types of iRoboCaps were designed, one was a submarine type (iRoboCap-S) and the other was an amphibious type (iRoboCap-A). They were remotely and wirelessly steered by a portable tablet device using Bluetooth and via the internet. The success rates of biopsy or clipping were evaluated in a phantom. Although the two prototypes have various problems that need improving, we hope that our robotic and wireless innovations have opened the door to new endoscopic procedures and will pioneer various new applications in medicine.


Asunto(s)
Biopsia/métodos , Endoscopios en Cápsulas , Endoscopía Capsular/instrumentación , Enfermedades Gastrointestinales/diagnóstico , Robótica/instrumentación , Telemedicina/métodos , Endoscopía Capsular/métodos , Endoscopía , Diseño de Equipo , Humanos , Internet , Fantasmas de Imagen , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador
13.
J Gastroenterol ; 49(2): 239-44, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23595613

RESUMEN

BACKGROUND: It is not clear what kind of drug is appropriate to heal NSAID-induced enteropathy. Several reports showed the preventive effect of prostaglandin analogue or inducer using healthy subjects who took NSAIDs. However there was no report for healing effect and for patients. The aim of this study was to evaluate the healing effect of rebamipide in patients with NSAIDs-induced enteropathy. In addition, we evaluated for nutritional parameter. METHODS: This study was conducted as a randomized, double-blinded, placebo-controlled, multicenter trial. Study protocol was approved by each hospital's ethical committees. Patients with LDA and/or NSAID more than 3 months were enrolled. Patients with enteropathy were divided into the placebo and the rebamipide groups. Rebamipide 100 mg three times daily was administered during 4 weeks. Capsule endoscopies were performed at 0 and 4 week. The number of small intestinal ulcer and erosion were evaluated. Total protein was analyzed as nutritional parameter. RESULTS: Sixty one participants were completed this study. Change in number of small intestinal erosion in the rebamipide group was -2.5 ± 3.4, and 2.1 ± 3.9 in the placebo group (P < 0.0001). Change in number of small intestinal ulcer in the rebamipide group was -0.5 ± 1.6, and 0.1 ± 0.7 in the placebo group (P = 0.024). Change in serum total protein levels in the rebamipide group was 0.06 ± 0.36, and -0.27 ± 0.34 in the placebo group (P = 0.0005). CONCLUSIONS: Rebamipide has not only the healing effect for NSAIDs-induced enteropathy compared with placebo, but the improvement of nutritional condition. These results showed a tentative therapeutical strategy for chronic NSAIDs users.


Asunto(s)
Alanina/análogos & derivados , Antiinflamatorios no Esteroideos/efectos adversos , Antiulcerosos/uso terapéutico , Aspirina/efectos adversos , Enfermedades Intestinales/tratamiento farmacológico , Mucosa Intestinal/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Quinolonas/uso terapéutico , Anciano , Alanina/uso terapéutico , Antiinflamatorios no Esteroideos/administración & dosificación , Aspirina/administración & dosificación , Endoscopía Capsular , Proteínas en la Dieta/sangre , Método Doble Ciego , Femenino , Humanos , Enfermedades Intestinales/inducido químicamente , Enfermedades Intestinales/patología , Mucosa Intestinal/lesiones , Mucosa Intestinal/patología , Intestino Delgado/lesiones , Intestino Delgado/patología , Masculino , Persona de Mediana Edad , Cicatrización de Heridas
14.
Org Lett ; 15(3): 628-31, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23330691

RESUMEN

Practical and versatile syntheses of tertiary phosphine derivatives have been achieved by palladium-catalyzed deformylative P-C cross-coupling reactions of hydroxymethylphosphine derivatives. Sequential couplings of orthogonally protected precursors provide a simple and practical route toward a variety of tertiary phosphine derivatives having aryl substituents in any combination.

15.
Chem Commun (Camb) ; 47(44): 12209-11, 2011 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-21991582

RESUMEN

Carbon-supported Pt catalysts are highly active and reusable for the aqueous-phase hydrodeoxygenation of phenols as lignin models without adding any acids. It is suggested that Pt/carbon facilitates the hydrogenation of phenols and the hydrogenolysis of the resulting cyclohexanols.


Asunto(s)
Carbono/química , Oxígeno/química , Fenoles/química , Platino (Metal)/química , Catálisis , Ciclohexanoles/química , Hidrogenación , Lignina/química , Agua/química
16.
Org Lett ; 13(15): 3892-5, 2011 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-21714487

RESUMEN

An in-water dehydrative alkylation with a novel heterobimetallic polymeric catalyst is described. Thus, a boron-iridium heterobimetallic polymeric catalyst was prepared by ionic convolution of a poly(catechol borate) and an iridium complex. The alkylation of ammonia and amines with alcohols, alkylating agents, was performed with 1 mol % Ir of the heterogeneous catalyst in water without the use of organic solvents under aerobic conditions to give the corresponding alkylated amines.


Asunto(s)
Alcoholes/química , Aminas/química , Amoníaco/química , Iridio/química , Agua/química , Alquilación , Estructura Molecular
17.
Chem Asian J ; 6(9): 2545-9, 2011 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-21751405

RESUMEN

The development of a highly active solid-phase catechol-copper network catalyst for direct aldol reaction is described. The catalyst was prepared from an alkyl-chain-linked bis(catechol) and a copper(II) complex. The direct aldol reaction between carbonyl compounds (aldehydes and ketones) and methyl isocyanoacetate was carried out using 0.1-1 mol% [Cu] catalyst to give the corresponding oxazolines at yields of up to 99% and a trans/cis ratio of >99:1. The catalyst was reused with no loss of catalytic activity. A plausible reaction pathway is also described.

18.
Cancer Chemother Pharmacol ; 66(4): 721-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20041328

RESUMEN

PURPOSE: We evaluated the activity and toxicity of docetaxel, cisplatin, and S-1 (DCS) combination chemotherapy in patients with unresectable metastatic gastric cancer. METHODS: Patients with histologically proven, unresectable metastatic gastric adenocarcinoma, performance status (PS) 0-2, and no prior chemotherapy were eligible. Patients received oral S-1 (40 mg/m(2) b.i.d.) on days 1-14 and intravenous cisplatin (60 mg/m(2)) and docetaxel (60 mg/m(2)) on day 8 every 3 weeks. RESULTS: Thirty-four patients were enrolled between March 2005 and April 2007. Three patients were considered ineligible and did not receive the DSC therapy. Clinical characteristics were as follows: median age, 63 years (range, 44-77); PS, 0/1/2: 23/8/0; women/men, 8/23; and well-differentiated/undifferentiated adenocarcinoma, 10/21. The objective response rate was 87.1% with 1 complete response (3.2%) and 26 partial responses (83.9%) in 31 assessable patients. Four had stable disease (12.9%) but none had progressive disease. Of these 27 responders, 8 (25.8%) achieved downstaging and 7 (22.6%) underwent curative surgery. The median survival time and progression-free survival were 687 days [confidence interval (95% CI), 600.0-1,138.1] and 226 days (95% CI, 182.5-379.3), respectively. Most common grade 3/4 hematologic toxicity was neutropenia (77.4%). Most common grade 3 nonhematologic toxicities included anorexia (35.5%) and nausea (32.3%). All treatment-related toxicities resolved, and no toxic deaths were observed. CONCLUSIONS: DCS combination chemotherapy is highly active against unresectable metastatic gastric cancer and can be given safely with proper management of adverse events. Further studies of this combination are warranted.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Antimetabolitos Antineoplásicos/administración & dosificación , Antineoplásicos/administración & dosificación , Antineoplásicos Fitogénicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Cisplatino/administración & dosificación , Docetaxel , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Femenino , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Metástasis de la Neoplasia , Neutropenia/inducido químicamente , Neutropenia/tratamiento farmacológico , Ácido Oxónico/administración & dosificación , Neoplasias Gástricas/patología , Análisis de Supervivencia , Taxoides/administración & dosificación , Tegafur/administración & dosificación , Resultado del Tratamiento
19.
Nihon Shokakibyo Gakkai Zasshi ; 106(9): 1327-33, 2009 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-19734704

RESUMEN

A 54-year-old man was referred to our hospital with an esophageal lesion. On esophagogastroduodenoscopy a pedunculated elevated lesion about 15mm in diameter was identified in the abdominal esophagus. The surface of the lesion had irregular nodules with white coating. We found no Barrett's mucosa around the lesion. A biopsy specimen of this tumor showed well-differentiated adenocarcinoma. A lower esophagus-proximal gastrectomy was performed because this tumor was suspected to invade the submucosal layer. Eventually, the histological diagnosis after resection was esophageal adenocarcinoma arising from cardiac glands, limited to the mucosal layer (M2). This origin of the esophageal adenocarcinoma is rare. Furthermore, this form of the tumor is especially unusual, and there have been few reports of similar cases.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Esofágicas/patología , Humanos , Masculino , Persona de Mediana Edad , Membrana Mucosa/patología
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