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1.
Eur Rev Med Pharmacol Sci ; 26(7): 2422-2430, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35442497

RESUMEN

OBJECTIVE: Essence of chicken (EOC), a hot water extract of chicken, is widely consumed in Southeast Asia as a beverage. EOC has an inhibitory effect on the elevation of blood glucose levels and a secretagogue effect on insulin. However, the mechanism by which EOC promotes insulin secretion is unknown. We aimed to verify the postprandial hyperglycemic inhibitory effect and the insulin secretory effect of EOC in healthy adults under appropriate placebo settings. In addition, we aimed to understand the mechanism underlying the insulin secretory effect of EOC. PATIENTS AND METHODS: Thirty-four healthy Japanese adults were fed 68 mL of EOC or control food, followed by 200 g of cooked rice. Blood glucose and plasma insulin levels were measured at 30, 45, 60, 90, and 120 min after the participants ate cooked rice. The trial had a randomized, double-blind, crossover, placebo-controlled design. RESULTS: The ingestion of EOC induced an increase in the maximum blood concentration (Cmax) of insulin and shortened the time required to reach the maximum blood concentration following rice consumption. Ingestion of the test beverage resulted in a significantly higher insulinogenic index than that obtained after ingestion of the control beverage. No side effects were observed in this study. Mechanistic experiments revealed that EOC stimulated significant (p < 0.05) secretion of GLP-1 from NCI-H716 human intestinal L cells at 0.1, 1, and 10 mg/mL. CONCLUSIONS: Consuming EOC when eating rice supports pancreatic function. Daily consumption of EOC could elevate the early-phase insulin response; therefore, it could prevent diabetes in Asians with low insulin secretion.


Asunto(s)
Glucemia , Pollos , Animales , Glucemia/análisis , Glucemia/metabolismo , Pollos/metabolismo , Estudios Cruzados , Método Doble Ciego , Humanos , Insulina , Secreción de Insulina , Periodo Posprandial/fisiología , Agua
2.
Lab Chip ; 18(1): 115-125, 2017 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-29184959

RESUMEN

This paper reports a multi-throughput multi-organ-on-a-chip system formed on a pneumatic pressure-driven medium circulation platform with a microplate-sized format as a novel type of microphysiological system. The pneumatic pressure-driven platform enabled parallelized multi-organ experiments (i.e. simultaneous operation of multiple multi-organ culture units) and pipette-friendly liquid handling for various conventional cell culture experiments, including cell seeding, medium change, live/dead staining, cell growth analysis, gene expression analysis of collected cells, and liquid chromatography-mass spectrometry analysis of chemical compounds in the culture medium. An eight-throughput two-organ system and a four-throughput four-organ system were constructed on a common platform, with different microfluidic plates. The two-organ system, composed of liver and cancer models, was used to demonstrate the effect of an anticancer prodrug, capecitabine (CAP), whose metabolite 5-fluorouracil (5-FU) after metabolism by HepaRG hepatic cells inhibited the proliferation of HCT-116 cancer cells. The four-organ system, composed of intestine, liver, cancer, and connective tissue models, was used to demonstrate evaluation of the effects of 5-FU and two prodrugs of 5-FU (CAP and tegafur) on multiple organ models, including cancer and connective tissue.


Asunto(s)
Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas de Cultivo de Órganos/instrumentación , Células CACO-2 , Técnicas de Cultivo de Célula/instrumentación , Diseño de Equipo , Células HCT116 , Humanos , Modelos Biológicos , Presión
3.
Lab Chip ; 16(12): 2339-48, 2016 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-27229626

RESUMEN

Here, we report a pneumatic pressure-driven microfluidic device capable of multi-throughput medium circulation culture. The circulation culture system has the following advantages for application in drug discovery: (i) simultaneous operation of multiple circulation units, (ii) use of a small amount of circulating medium (3.5 mL), (iii) pipette-friendly liquid handling, and (iv) a detachable interface with pneumatic pressure lines via sterile air-vent filters. The microfluidic device contains three independent circulation culture units, in which human umbilical vein endothelial cells (HUVECs) were cultured under physiological shear stress induced by circulation of the medium. Circulation of the medium in the three culture units was generated by programmed sequentially applied pressure from two pressure-control lines. HUVECs cultured in the microfluidic device were aligned under a one-way circulating flow with a shear stress of 10 dyn cm(-2); they exhibited a randomly ordered alignment under no shear stress and under reciprocating flow with a shear stress of 10 dyn cm(-2). We also observed 2.8- to 4.9-fold increases in expression of the mRNAs of endothelial nitric oxide synthase and thrombomodulin under one-way circulating flow with a shear stress of 10 dyn cm(-2) compared with conditions of no shear stress or reciprocating flow.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Microfluídica/instrumentación , Recuento de Células , Medios de Cultivo , Fluoresceínas , Colorantes Fluorescentes , Células Endoteliales de la Vena Umbilical Humana , Humanos , Dispositivos Laboratorio en un Chip , Óxido Nítrico Sintasa de Tipo III/genética , Estrés Mecánico , Trombomodulina/genética
4.
Int J Hyperthermia ; 26(5): 465-74, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20377361

RESUMEN

PURPOSE: Although induction heating cancer therapy (IHCT) using magnetic nanoparticles can be a promising approach to treatment-less multi-nodular cancers, the objective requirement for successful clinical application has not clearly been elucidated. We intended to define objective heat doses suitable for IHCT, especially focusing on the sizes of liver cancer nodules. MATERIALS AND METHODS: Alternating magnetic fields were applied to three human pancreatic cancer cell lines, the intercellular space of those cell pellets were filled with magnetic nanoparticles, and confirmed the cytotoxic effect of IHCT. Subsequently, the temperatures of liver cancer nodules in IHCT were simulated using a computer software program and the required heat dose for various sized tumours were determined. RESULTS: Heating the cancer cells up to 50 degrees C for 10 min was sufficient for complete cell killing and the heat dose of 1.7 W/g(tumour) is required for 10 mm tumour. Larger tumours require a smaller heat dose, e.g. 20 mm and 40 mm tumours require 0.7 W/g(tumour) and 0.6 W/g(tumour), respectively, whereas smaller tumours require large amounts of heat, e.g. 5 mm and 1 mm tumours require 5.1 W/g(tumour) and 105 W/g(tumour), respectively. CONCLUSIONS: Integrating the presently available technologies, including high-quality magnetic nanoparticles (1000 W/g(material)) and effective drug delivery systems (1-2 mg(material)/g(tumour)), treatment of a 10 mm tumour seems possible. Since treatment of smaller tumours less than 5 mm require substantial heat dose, researchers involved in IHCT should target cancer nodules of 10 mm or more, and develop a heat delivery system providing a minimum of 1.7 W/g(tumour).


Asunto(s)
Calor , Hipertermia Inducida/métodos , Neoplasias/terapia , Línea Celular Tumoral , Supervivencia Celular , Simulación por Computador , Dextranos , Óxido Ferrosoférrico , Humanos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , Magnetismo , Nanopartículas de Magnetita , Nanopartículas , Neoplasias Pancreáticas/terapia
5.
Phys Med Biol ; 54(8): 2571-83, 2009 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-19349659

RESUMEN

Magnetic nanoparticles have recently been widely applied in the bio-medical field. Responding to the demand for a simple and sensitive magnetic assay system for bio-liquid samples, we employed a general-purpose superconducting quantum interference device (SQUID) magnetometer. Strips of filter paper were used as a liquid-specimen sample holder possessing a very small magnetic background signal. An aqueous solution of superparamagnetic iron-oxide nanoparticles (Resovist) was dropped in a tiny blot-like spot in the middle of the filter paper and the magnetization was measured. Magnetic moments of a dilution series of Resovist solutions versus the number of particles provided a linear graph, revealing that the magnetic moment per Resovist particle was 8.25 x 10(-17) emu. 1 x 10(5) cancer cells were incubated with Resovist, and the number of Resovist particles attached to the cell surface and surrounding a living cell was calculated to be 1.02 +/- 0.14 x 10(7) particles/cell. Our system using a commercial SQUID magnetometer should be more than enough to determine the number of magnetic nanoparticles biologically reacting with living cells, contributing to the application of magneto nanomaterials to the life-science field.


Asunto(s)
Magnetismo , Nanopartículas , Calibración , Línea Celular Tumoral , Supervivencia Celular , Filtración , Humanos , Papel , Sensibilidad y Especificidad
6.
Xenobiotica ; 39(5): 391-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19280383

RESUMEN

Salvinorin A is the main active psychoactive ingredient in Salvia divinorum, a Mexican plant that has been widely available as a hallucinogen in recent years. The aims of this study were to investigate the stability of salvinorin A in rat plasma, esterases responsible for its degradation, and estimation of the degradation products. The apparent first-order rate constants of salvinorin A at 37 degrees C, 25 degrees C, and 4 degrees C were 3.8 x 10(-1), 1.1 x 10(-1), and < 6.0 x 10(-3) h(-1), respectively. Salvinorin A degradation was markedly inhibited by the addition of sodium fluoride, an esterase inhibitor. Moreover, phenylmethylsulfonyl fluoride (serine esterase inhibitor) and bis-p-nitrophenylphosphate (carboxylesterase inhibitor) also inhibited salvinorin A degradation. In contrast, little or no suppression of the degradation was seen with 5,5'-dithiobis-2-nitrobenzoic acid (arylesterase inhibitor),ethopropazine (butyrylcholinesterase inhibitor), and BW284c51 (acetylcholineseterase inhibitor). These findings indicated that carboxylesterase was mainly involved in the salvinorin A hydrolysis in rat plasma.4. The degradation products of salvinorin A estimated by liquid chromatography-mass spectrometry included the deacetylated form (salvinorin B) and the lactone-ring-open forms of salvinorin A and salvinorin B. This lactone-ring-opening reactions were involved in calcium-dependent lactonase.


Asunto(s)
Diterpenos de Tipo Clerodano/farmacocinética , Diterpenos/farmacocinética , Esterasas/metabolismo , Alucinógenos/farmacocinética , Animales , Diterpenos/sangre , Diterpenos de Tipo Clerodano/sangre , Estabilidad de Medicamentos , Inhibidores Enzimáticos/farmacología , Esterasas/antagonistas & inhibidores , Alucinógenos/sangre , Masculino , Ratas , Ratas Wistar , Salvia/química
7.
J Dent Res ; 87(12): 1117-21, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19029078

RESUMEN

Residual monomers in resin-based biomaterials cause cytotoxicity. We previously showed that methyl methacrylate (MMA) induced mRNA expression of the glutathione S-transferase alpha 1 gene (Gsta1) located downstream of the cis-acting anti-oxidant responsive element (ARE). Herein, we tested the hypothesis that MMA activated the Gsta1 promoter through the ARE. HepG2 cells were transfected with a luciferase reporter vector containing the ARE and the Gsta1 promoter (-990 to +46 bp) and cultured for 12 hrs with MMA (initial concentration, 10 mM). Analysis of the expressed luciferase activity indicated that MMA activated the promoter 2.6-fold. MMA (from 1 to 30 mM) dose-dependently increased the promoter activity, which reached a plateau between 6 and 12 hrs. In HepG2 cells transfected with a reporter vector containing 2 AREs and a TATA-like promoter, 10 mM MMA increased the reporter expression 2.8-fold. These results suggest that MMA increases Gsta1 transcription through ARE-mediated promoter activation.


Asunto(s)
Materiales Dentales/farmacología , Glutatión Transferasa/genética , Isoenzimas/genética , Metilmetacrilato/farmacología , Regiones Promotoras Genéticas/genética , Activación Transcripcional/efectos de los fármacos , Región de Flanqueo 5'/efectos de los fármacos , Región de Flanqueo 5'/genética , Animales , Antioxidantes/farmacología , Recuento de Células , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Genes Reporteros/genética , Vectores Genéticos/genética , Glutatión Transferasa/efectos de los fármacos , Humanos , Hidroquinonas/farmacología , Isoenzimas/efectos de los fármacos , Luciferasas/genética , Metilmetacrilato/administración & dosificación , Ratones , Plásmidos/genética , Regiones Promotoras Genéticas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Elementos de Respuesta/efectos de los fármacos , Elementos de Respuesta/genética , TATA Box/genética , Secuencias Repetidas en Tándem/efectos de los fármacos , Secuencias Repetidas en Tándem/genética , Factores de Tiempo , Transfección
8.
Xenobiotica ; 38(12): 1476-86, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18982537

RESUMEN

1. The in vivo metabolism of alpha-methyltryptamine (AMT), a psychoactive tryptamine analogue, was studied in rats. 2. Male Wistar rats were administered 10 mg kg(-1) AMT orally and 24-h urine fractions were collected. After enzymatic hydrolysis of the urine sample, the metabolites were extracted by liquid-liquid extraction and analysed by gas chromatography/mass spectrometry (GC/MS). 3. 2-Oxo-AMT, 6-hydroxy-AMT, 7-hydroxy-AMT and 1'-hydroxy-AMT were detected as metabolites of AMT.


Asunto(s)
Triptaminas/orina , Animales , Cromatografía de Gases y Espectrometría de Masas , Masculino , Ratas , Ratas Wistar , Triptaminas/administración & dosificación , Triptaminas/metabolismo
9.
Xenobiotica ; 37(6): 679-92, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17614010

RESUMEN

The in vivo metabolism of 2,5-dimethoxy-4-propylthiophenethylamine (2C-T-7), a ring-substituted psychoactive phenethylamine, was studied in rat. Male Wistar rats were administered 10 mg/kg 2C-T-7 hydrochloride orally, and 24-h urine fractions were collected. After enzymatic hydrolysis of the urine sample, the metabolites were extracted by liquid-liquid extraction and analyzed by liquid chromatography/mass spectrometry. 2C-T-7-sulfoxide, N-acetyl-2C-T-7-sulfoxide, N-acetyl-2,5-dimethoxy-4-methylthiophenethylamine-sulfoxide, N-acetyl-2,5-dimethoxy-4-(2-hydroxypropylthio)phenethylamine-sulfoxide, and N-acetyl-2,5-dimethoxy-4-(2-hydroxypropylthio)phenethylamine-sulfone were detected as the primary metabolites of 2C-T-7. These findings suggest that sulfoxidation, sulfone formation, hydroxylation of the propyl side chain at the beta-position, and S-depropylation followed by methylation of thiol were the major metabolic pathways of 2C-T-7 in rat.


Asunto(s)
Fenetilaminas/farmacocinética , Psicotrópicos/farmacocinética , Animales , Cromatografía Liquida , Masculino , Espectrometría de Masas , Fenetilaminas/química , Fenetilaminas/orina , Psicotrópicos/química , Psicotrópicos/orina , Ratas , Ratas Wistar
10.
Kyobu Geka ; 60(4): 279-84, 2007 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-17416093

RESUMEN

We evaluated the results of 213 emergency operations of acute type A aortic dissection in our center from January 2003 to December 2006. They were 101 male and 112 female, and the mean age was 64.6 years. The hospital mortality rate of all cases was 13.6% (29/213). And that of cases with malperfusion was 31.9% (15/47). They consisted of stroke 8/17 (47.1%), myocardial ischemia 5/27 (18.5%) [right coronary artery: 2/22 (9.1%), left main trunk: 3/5 (60.0%)], and intestinal ischemia 2/3 (66.7%). The hospital mortality rate of pulseless electrical activity (PEA) cases was 57.1% (4/7), and that of aortic rupture cases was 33.3% (3/9). On the other hand, the mortality rate of cases with cardiac tamponade alone was 4/45 (8.9%). That of cases without cardiac tamponade and malperfusion was 3/105 (2.9%), and was significantly (p < 0.05) lower than that with malperfusion.


Asunto(s)
Aneurisma de la Aorta Torácica/mortalidad , Aneurisma de la Aorta/mortalidad , Disección Aórtica/mortalidad , Implantación de Prótesis Vascular , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Disección Aórtica/cirugía , Aorta/cirugía , Aneurisma de la Aorta/cirugía , Aneurisma de la Aorta Torácica/cirugía , Urgencias Médicas , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Tasa de Supervivencia
11.
Forensic Sci Int ; 148(2-3): 131-7, 2005 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-15639607

RESUMEN

The metabolism of methamphetamine (MA) and 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in freshly isolated rat hepatocytes was investigated, and compared with in vivo results. A suspended hepatocyte culture, established from male Wistar rats using a collagenase perfusion technique, was incubated in the presence of MA or 2C-B. After enzymatic hydrolysis of the conjugated forms, the metabolites were extracted by liquid-liquid partition and analyzed by gas chromatography/mass spectrometry (GC/MS). Amphetamine, p-hydroxymethamphetamine and p-hydroxyamphetamine were detected in the culture fluids of the rat hepatocytes inoculated with MA. The alcohol derivative, carboxylic acid derivative, 2-O-desmethyl-2C-B, 2-O-desmethyl-N-acetyl-2C-B and 5-O-desmethyl-N-acetyl-2C-B were detected in the case of 2C-B. The major metabolite of MA in rat hepatocytes was p-hydroxymethamphetamine. This is in good agreement with the urinary excretion profile for rats that were fed MA. 2-O-Desmethyl-2C-B and the carboxylic acid derivative were the major recovered metabolites of 2C-B in the rat hepatocyte culture, a slight deviation from the in vivo findings, in which 5-O-desmethyl-N-acetyl-2C-B was found to be the main component. Metabolites with a hydroxy group were largely present in their conjugated forms in the culture fluids, except for 2-O-desmethyl-2C-B. Taking these results into consideration, a primary hepatocyte culture system has the potential to provide a quick and handy method for estimating the in vivo metabolic fate of abused drugs.


Asunto(s)
Estimulantes del Sistema Nervioso Central/metabolismo , 2,5-Dimetoxi-4-Metilanfetamina/análogos & derivados , 2,5-Dimetoxi-4-Metilanfetamina/metabolismo , Alucinógenos/metabolismo , Hepatocitos/metabolismo , Metanfetamina/análogos & derivados , Metanfetamina/metabolismo , Anfetamina/metabolismo , Animales , Ácidos Carboxílicos/química , Células Cultivadas , Cromatografía de Gases y Espectrometría de Masas , Masculino , Modelos Animales , Estructura Molecular , Ratas , Ratas Wistar , Simpatomiméticos/metabolismo , p-Hidroxianfetamina/metabolismo
12.
Int J Artif Organs ; 26(4): 308-18, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12757030

RESUMEN

We propose a new bioartificial liver (BAL) system equipped with a high performance hemodialyzer to act as an immunoisolation device. We discuss the design of the BAL system using a mathematical kinetic model with the experimentally obtained mass-transfer performances of various hemodialyzers. The mass transfer resistances of the hemodialyzers did not adversely influence the ammonia-removal and bioactive-substance-supply performances of the BAL system. A suitable hemodialyzer for the BAL system is available even at present using an engineering design. The remaining problems to be overcome before realizing clinical use of the BAL system are to increase the rate constant of the first order reaction of the BAL for ammonia metabolism and to develop a new method of blood access that can be used safely with long term reliability at a high blood flow rate (ca. 556 ml/min).


Asunto(s)
Separación Celular/instrumentación , Diseño de Equipo , Cinética , Fallo Hepático/inmunología , Fallo Hepático/terapia , Hígado Artificial , Modelos Teóricos , Diálisis Renal/instrumentación , Simulación por Computador , Humanos , Peso Molecular
13.
Gene Ther ; 8(14): 1043-50, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11526451

RESUMEN

We scrutinized the applicability and efficacy of Sendai virus (SeV) vectors expressing either LacZ or human insulin-like growth factor-I (hIGF-I) in gene transfer into skeletal muscle. Seven days after the intramuscular injection of LacZ/SeV X-gal labeled myofibers were demonstrated in rat anterior tibialis muscle with/without bupivacaine treatment and the transgene expression persisted up to 1 month after injection. Recombinant hIGF-I was detected as a major protein species in culture supernatants of a neonatal rat myoblast cell line L6 and thus induced the cells to undergo myogenetic differentiation. The introduction of hIGF-I/SeV into the muscle showed a significant increase in regenerating and split myofibers which were indicative of hypertrophy, and also an increase in the total number of myofibers, in comparison to that seen in the LacZ/SeV-treated control muscle. These results demonstrate that SeV achieves high-level transgene expression in skeletal muscle, and that hIGF-I gene transfer using SeV vector may therefore have great potential in the treatment of neuromuscular disorders.


Asunto(s)
Terapia Genética/métodos , Vectores Genéticos/administración & dosificación , Factor I del Crecimiento Similar a la Insulina/genética , Músculo Esquelético/fisiología , Enfermedades Neuromusculares/terapia , Regeneración , Animales , Células Cultivadas , Expresión Génica , Miembro Posterior , Humanos , Inyecciones Intramusculares , Factor I del Crecimiento Similar a la Insulina/análisis , Operón Lac , Masculino , Modelos Animales , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/análisis , Respirovirus/genética , Transfección/métodos , Transgenes
14.
J Biomater Sci Polym Ed ; 12(5): 533-42, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11469783

RESUMEN

We have fabricated an asymmetric polyimide hollow fiber for use as a membrane oxygenator. A dry/wet phase inversion process has been applied to a spinning process to prepare the hollow fiber. The fiber structure consisted of a complete defect-free skin layer and a porous substructure characterized by the presence of an open-cell structure and macrovoids. The outer diameter was 480 microm with a wall thickness of 50 microm. Transfer rates of O2 and CO2 in the asymmetric polyimide fiber were 2.3 x 10(-5) and 1.1 x 10(-4) (cm3 (STP)/(cm2 s cmHg)), respectively, which were four times higher than those measured in the polydimethylsiloxane (PDMS) fiber of the presently-available membrane oxygenator. The (QO2/QN2) selectivity of the polyimide fiber was 4.9, indicating that the surface skin layer is essentially defect-free. The blood compatibility of the polyimide hollow fiber has been evaluated in vitro and in vivo. The polyimide had an excellent blood compatibility when compared with PDMS.


Asunto(s)
Materiales Biocompatibles/química , Proteínas Sanguíneas/metabolismo , Imidas/química , Oxigenadores de Membrana/normas , Polímeros/química , Adsorción , Animales , Materiales Biocompatibles/normas , Dióxido de Carbono/metabolismo , Diseño de Equipo , Humanos , Microscopía Electrónica de Rastreo , Oxígeno/metabolismo , Permeabilidad , Adhesividad Plaquetaria , Conejos , Venas Cavas
15.
Anal Chem ; 73(8): 1849-54, 2001 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-11338601

RESUMEN

A triethylammonium-sensitive electrode was constructed using sodium tetrakis[3,5-bis(2-methoxyhexafluoro-2-propyl)phenyl]borate as an ion-exchanger and benzyl 2-nitrophenyl ether as a solvent mediator in a poly(vinylchloride) membrane matrix and was used to determine the pH difference across a cell membrane. The method is based on monitoring of the pH gradient-induced uptake of triethylammonium in situ. The triethylammonium electrode exhibited a near-Nernstian response to triethylammonium in the concentration range of 5 x 10(-6)-1 x 10(-2) M with a slope of 58.5 mV per concentration decade in a buffer solution composed of 150 mM NaCl and 10 mM NaH2PO4/Na2HPO4 (pH 7.5). The limit of detection was 1 microM. In experiments using liposomes, the uptake of triethylammonium into liposomes was quantitatively induced according to the pH difference across the liposomal membrane. The transmembrane pH differences in Escherichia coli cells and the light-induced pH differences across the envelope vesicles of Halobacterium halobium were successfully determined by the present method.


Asunto(s)
Membrana Celular/química , Escherichia coli/química , Halobacterium/química , Concentración de Iones de Hidrógeno , Liposomas , Microelectrodos
16.
Kyobu Geka ; 54(1): 42-6, 2001 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-11197909

RESUMEN

The purpose of this study was to evaluate the results of carinal resection for bronchogenic carcinoma in our institute. From 1981 to 1999, 24 carinal resection were performed for squamous cell carcinoma (n = 19), adenoid cystic carcinoma (n = 2), small cell carcinoma (n = 1), adenocarcinoma (n = 1), and mucoepidermoid carcinoma (n = 1). Nineteen underwent sleeve pneumonectomy, 2 had carinal resection without lung resection, 2 had carinal resection with right middle and lower lobectomy, and 1 had wedge pneumonectomy. In the patients with sleeve or wedge pneumonectomy, there were 5 operative death and 3 patients had survived for more than 3 years. Two patients with low-grade malignant tumors underwent carinal resection without lung resection and survived more than 10 years. We believe that limited carinal resection for low-grade malignant tumors are safe and valuable procedure. Careful selection of patients with sleeve or wedge pneumonectomy is mandatory.


Asunto(s)
Carcinoma Broncogénico/cirugía , Neoplasias Pulmonares/cirugía , Procedimientos de Cirugía Plástica/métodos , Tráquea/cirugía , Adulto , Anciano , Carcinoma Adenoide Quístico/cirugía , Carcinoma de Células Escamosas/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neumonectomía , Pronóstico , Estudios Retrospectivos
17.
Kyobu Geka ; 53(11): 905-9, 2000 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-11048439

RESUMEN

The purpose of this study was to evaluate the results of new TNM staging system for lung cancer in 1997, especially T3N0M0, stage IIIA, stage IIIB, and pm. Five-year survival rates of the patients with stage IIIA and stage IIIB were 16% and 18% respectively (NS). Five-year survival rates of patients with T3N1M0, T1N2M0, T2N2M0, and T3N2M0 were 40%, 28%, 15%, and 3%, respectively. The prognosis of T3N2M0 was significantly worse than that of T3N1M0, T1N2M0, and T2N2M0. Five-year survival rates of the patients excluding pm 1 with T4N0M0, T4N1M0, T4N2M0, and T4N3M0 were 21%, 10%, 10%, and 0%, respectively. The prognosis of the patients with T4N0 was significantly better than that of T4N2 and T4N3. In the patients with pm, 5-year survival rates of the patients with pm 1 and pm 2 were 26% and 7%, respectively (p < 0.01). In the patients with pm 1, 5-year survival rates of the patients with N0 + N1 and N1 + N2 were 53% and 16%, respectively (p < 0.01). From our these results, we supported the new TNM system as putting T3N0M0 to stage IIB, putting pm 2 into stage IV. We proposed; 1) chest wall invasion with bone destruction stay in stage IIIA or is T4, 2) T3N1M0 is classified with stage IIB, 3) main stem bronchus invasion is classified with T2, 4) pm 1 is subdivide by N status. Furthermore, stage III seemed to be reasonably subdivided into T1-2N3M0, T4N0-1M0 as stage IIIA and T3-4N2, T1-4N3 as stage IIIB.


Asunto(s)
Neoplasias Pulmonares/patología , Estadificación de Neoplasias/métodos , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/cirugía , Neumonectomía , Pronóstico , Análisis de Supervivencia
18.
ASAIO J ; 46(5): 612-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11016518

RESUMEN

An asymmetric hollow fiber membrane was prepared from a newly synthesized fluorinated aromatic polyimide (6FDA-6FAP) by using a dry/wet phase inversion process. The membrane was used in a membrane oxygenator over a long period of time. In this study, the potential of the membrane for intravascular membrane oxygenation (IVOX) was studied in respect to oxygen transfer. The gas permeance of the membrane and three commercially available hollow fiber membranes for membrane oxygenators was measured in a gas-gas system and a gas-liquid system and discussed relative to the membrane structures. The oxygen transfer rates of the IVOX devices using these four membranes were estimated by a mathematical kinetic model, with the oxygen permeance measured in the gas-liquid system. The results showed that the device using the 6FDA-6FAP hollow fiber membrane has the highest oxygen transfer rate and is believed to be applicable to IVOX. The methods to determine oxygen transfer rate of a hollow fiber membrane and the mathematical kinetic model, are useful for developing a hollow fiber membrane and a device for oxygenation.


Asunto(s)
Oxígeno/metabolismo , Oxigenadores de Membrana , Humanos , Permeabilidad
19.
J Chromatogr A ; 877(1-2): 61-9, 2000 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-10845789

RESUMEN

A cyclophane (CP66)-bonded silica gel stationary phase (CP66-SP) was prepared and the retention of water-insoluble hydrophobic compounds on it was investigated in comparison with that on the CP44-bonded stationary phase (CP44-SP) reported previously. Like CP44-SP, it retained aromatic compounds more strongly than the corresponding alicyclic compounds, as was expected by the cavity size of the cyclophane. The CP66-SP also showed isomer-selectivity for monosubstituted and disubstituted naphthalenes, but its selectivity was perfectly reversed to that of the CP44-SP. On the CP66-SP, isomers having methyl and ethyl groups at beta-position were eluted prior to those having groups at alpha-position, whereas on the CP44-SP beta-substituted naphthalenes were retained more strongly than alpha-substituted ones. Isomers of three- and four-ring aromatic compounds were also separated on these cyclophane-bonded stationary phases. The retention order on the CP66-SP was almost opposite to that on the CP44-SP; on the CP66-SP, the retention order was phenanthrene > anthracene, and chrysene > 1,2-benzanthracene > 2,3-benzanthracene, whereas on the CP44-SP, anthracene > phenanthrene, and 2,3-benzanthracene > chrysene > 1,2-benzanthracene. The retention mechanism of aromatic compounds is discussed on the basis of the structure of the cyclophane-involved complex.


Asunto(s)
Éteres Cíclicos/química , Piperidinas/química , Cromatografía Liquida , Isomerismo , Espectrofotometría Ultravioleta
20.
Genes Dev ; 14(1): 11-6, 2000 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-10640270

RESUMEN

Antigenic stimulation of the B-cell receptor (BCR) is a central event in the immune response. In contrast, antigen bound to IgG negatively regulates signals from the BCR by cross-linking it to the inhibitory receptor FcgammaRIIB. Here we show that upon cross-linking of BCR or BCR with FcgammaRIIB, the rasGAP-associated protein p62(dok) is prominently tyrosine phosphorylated in a Lyn-dependent manner. Inactivation of the dok gene by homologous recombination has shown that upon BCR cross-linking, p62(dok) suppresses MAP kinase and is indispensable for FcgammaRIIB-mediated negative regulation of cell proliferation. We propose that p62(dok), a downstream target of many PTKs, plays a negative role in various signaling situations.


Asunto(s)
Proteínas de Unión al ADN , Fosfoproteínas/fisiología , Proteínas de Unión al ARN , Receptores de Antígenos de Linfocitos B/fisiología , Transducción de Señal , Animales , Femenino , Ratones , Ratones Endogámicos C57BL , Mutación , Fosfoproteínas/genética , Fosforilación , Receptores de IgG/metabolismo , Tirosina/metabolismo
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