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1.
Phys Rev Lett ; 116(9): 096602, 2016 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-26991190

RESUMEN

We present results on spin to charge current conversion in experiments of resonant spin pumping into the Dirac cone with helical spin polarization of the elemental topological insulator (TI) α-Sn. By angle-resolved photoelectron spectroscopy (ARPES), we first check that the Dirac cone (DC) at the α-Sn (0 0 1) surface subsists after covering Sn with Ag. Then we show that resonant spin pumping at room temperature from Fe through Ag into α-Sn layers induces a lateral charge current that can be ascribed to the inverse Edelstein effect by the DC states. Our observation of an inverse Edelstein effect length much longer than those generally found for Rashba interfaces demonstrates the potential of TIs for the conversion between spin and charge in spintronic devices. By comparing our results with data on the relaxation time of TI free surface states from time-resolved ARPES, we can anticipate the ultimate potential of the TI for spin to charge conversion and the conditions to reach it.


Asunto(s)
Modelos Teóricos , Estaño/química , Hierro/química , Espectroscopía de Fotoelectrones/métodos , Plata/química , Temperatura
2.
Phys Rev Lett ; 111(12): 126603, 2013 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-24093286

RESUMEN

We investigate the electronic states of BiTeI after the optical pumping with circularly polarized photons. Our data show that photoexcited electrons reach an internal thermalization within 300 fs of the arrival of the pump pulse. Instead, the dichroic contrast generated by the circularly polarized light relaxes on a time scale shorter than 80 fs. This result implies that orbital and spin polarization created by the circular pump pulse rapidly decays via manybody interaction. The persistent dichroism at longer delay times is due to the helicity dependence of superdiffussive transport. We ascribe it to the lack of inversion symmetry in an electronic system far from equilibrium conditions.

3.
Phys Rev Lett ; 109(22): 226404, 2012 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-23368140

RESUMEN

We investigate the bismuth (111) surface by means of time and angle resolved photoelectron spectroscopy. The parallel detection of the surface states below and above the Fermi level reveals a giant anisotropy of the spin-orbit spitting. These strong deviations from the Rashba-like coupling cannot be treated in k·p perturbation theory. Instead, first principles calculations could accurately reproduce the experimental dispersion of the electronic states. Our analysis shows that the giant anisotropy of the spin-orbit splitting is due to a large out-of plane buckling of the spin and orbital texture.

4.
Gene ; 256(1-2): 223-8, 2000 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-11054551

RESUMEN

The bph genes involved in PCB/biphenyl degradation in Pseudomonas sp. KKS102 are clustered as bphEGFA1A2A3BCDA4R. The bph genes are inducibly expressed in the presence of biphenyl. In order to understand the induction more fully, the inducer of bph gene expression was investigated. To identify the inducer molecule, we constructed four deletion mutants of the structural genes and analyzed the inducibility of the bphE gene in each mutant strain. In the wild-type cell and the bphD deletion mutant, the levels of the bphE transcript were enhanced in the presence of biphenyl. On the other hand, in the bphA, bphB, and bphC deletion mutants, levels of the bphE transcript were not enhanced in the presence of biphenyl. These results demonstrated that the series of reactions catalyzed by biphenyl dioxygenase (BphA), dihydrodiol dehydrogenase (BphB), and 2, 3-dihydroxybiphenyl dioxygenase (BphC) are necessary to convert biphenyl to the inducer. It is known that these reactions convert biphenyl to 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA), and it was found that the expression of the bph genes was induced by purified HOPDA. These results clearly indicate that HOPDA is the inducer of the bph genes in KKS102.


Asunto(s)
Dioxigenasas , Ácidos Grasos Insaturados/farmacología , Bifenilos Policlorados/metabolismo , Pseudomonas/efectos de los fármacos , Biodegradación Ambiental , Northern Blotting , ADN Recombinante/genética , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Mutación , Oxidorreductasas , Oxigenasas/genética , Pseudomonas/enzimología , Pseudomonas/genética
5.
FEBS Lett ; 459(3): 395-8, 1999 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-10526172

RESUMEN

The pentachlorophenol (PCP) mineralizing bacterium Sphingomonas chlorophenolica ATCC39723 degrades PCP via 2,6-dichlorohydroquinone (2,6-DCHQ). The pathway converting PCP to 2,6-DCHQ has been established previously; however, the pathway beyond 2,6-DCHQ is not clear, although it has been suggested that a PcpA plays a role in 2, 6-DCHQ conversion. In this study, PcpA expressed in Escherichia coli was purified to homogeneity and shown to have novel ring-cleavage dioxygenase activity in conjunction with hydroquinone derivatives, and converting 2,6-DCHQ to 2-chloromaleylacetate.


Asunto(s)
Proteínas Bacterianas , Proteínas Portadoras/metabolismo , Pentaclorofenol/metabolismo , Sphingomonas/enzimología , Secuencia de Aminoácidos , Proteínas Portadoras/genética , Escherichia coli , Hidroquinonas/metabolismo , Maleatos/metabolismo , Datos de Secuencia Molecular , Oxigenasas , Homología de Secuencia de Aminoácido
6.
J Drug Target ; 2(2): 157-65, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8069594

RESUMEN

Three types of bovine serum albumin (BSA) derivatives such as lactosylated BSA (LBSA), mannosylated BSA (Man-BSA), and cationized BSA (cBSA) were synthesized and their hepatic disposition characteristics in mice were evaluated by pharmacokinetic analysis. At lower doses (< or = 1 mg/kg), LBSA and Man-BSA were very rapidly eliminated from the blood circulation due to uptake by parenchymal and nonparenchymal cells of the liver, respectively, via receptor-mediated endocytosis (Nishikawa et al., 1992; Nishida et al., 1991a, b). These uptake processes were nonlinear and the apparent hepatic uptake clearances (CLliver) were decreased at administered doses higher than 1 mg/kg, e.g. 10, 20, and 100 mg/kg. The liver accumulation of cBSA was also nonlinear, but its binding and/or uptake capacity in the liver was larger than those of LBSA and Man-BSA; i.e., CLliver decreased at doses higher than 20 mg/kg. In the next step, we modified these BSA derivatives by attaching polyethylene glycol (PEG), a modifier known to reduce the hepatic uptake and increase plasma retention, to achieve precise control of the in vivo disposition characteristics of BSA derivatives. By conjugation with PEG having a molecular weight of 10 kDa, the CLliver values of LBSA, Man-BSA, and cBSA were decreasing to one-seventh, one-fortyfifth, and one-onehundredthirtieth, respectively. However, liver accumulation of PEG modified LBSA and Man-BSA at 24 h after i.v. injection was not significantly different from unmodified BSA derivatives. These results suggest that it is possible to control the hepatic uptake of protein drugs by a combination of introduction of charge or sugar moieties and PEG conjugation.


Asunto(s)
Albúmina Sérica Bovina/farmacocinética , Animales , Cationes/química , Fenómenos Químicos , Química Física , Endocitosis/efectos de los fármacos , Glucosa/química , Radioisótopos de Indio , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos , Polietilenglicoles/química , Receptores de Albúmina/metabolismo , Albúmina Sérica Bovina/química , Distribución Tisular
7.
Carbohydr Res ; 315(1-2): 142-7, 1999 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-10385977

RESUMEN

Three limonoid glycosides were isolated from Citrus unshiu peels, and their structures were determined based on MS and NMR spectroscopic data as nomilinic acid 17-O-beta-D-glucopyranoside (1), methyl nomilinate 17-O-beta-D-glucopyranoside (2), and obacunone 17-O-beta-D-glucopyranoside (3). In particular, the location of the sugar moiety was clearly determined by the B/E constant linked scan FABMS method. No limonoid glycosides obtained here were found to have antitumor activity in NCI-H292 and EL-4 cell lines.


Asunto(s)
Citrus/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Animales , Secuencia de Carbohidratos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Espectroscopía de Resonancia Magnética , Ratones , Datos de Secuencia Molecular , Células Tumorales Cultivadas
8.
J Agric Food Chem ; 47(2): 588-93, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10563937

RESUMEN

New polyisoprenepolyols (hypsiziprenol AA and BA) were isolated from an edible mushroom (Hypsizigus marmoreus). These polyols occur as a mixture of homologous polyisoprene derivatives with 40-70 carbon atoms. Analyses by FAB/MS in the positive and negative ion modes are complementary with each other in that the former provides information on the number of hydroxy groups present while the latter specifies the isoprenoid sequence, and thus become a powerful tool for analyzing the structures of polyisoprenepolyols. No polyisoprenepolyols obtained here were found to have antitumor activity on NCI-H292 and EL-4 cell lines.


Asunto(s)
Agaricales/química , Alcoholes Grasos/química , Terpenos/química , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Alcoholes Grasos/farmacología , Humanos , Indicadores y Reactivos , Espectrometría de Masa Bombardeada por Átomos Veloces , Gusto , Terpenos/farmacología , Células Tumorales Cultivadas
9.
Neurol Med Chir (Tokyo) ; 39(7): 544-7, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10437385

RESUMEN

A neonate presented with Dandy-Walker syndrome associated with occipital meningocele and spinal lipoma, manifesting as soft masses on the skull and lumbosacral regions. Magnetic resonance imaging demonstrated a large posterior fossa cyst between the fourth ventricle and occipital meningocele, but the aqueduct was patent and there was no sign of hydrocephalus. A cyst-peritoneal shunt was emplaced at the age of 8 days followed by partial removal of the spinal lipoma and untethering of the cord at the 3 months. Follow-up examination of age 3 years found almost normal development, although the cyst still persisted.


Asunto(s)
Síndrome de Dandy-Walker/complicaciones , Lipoma/complicaciones , Meningocele/complicaciones , Hueso Occipital , Neoplasias de la Columna Vertebral/complicaciones , Derivación Ventriculoperitoneal , Adulto , Síndrome de Dandy-Walker/diagnóstico , Síndrome de Dandy-Walker/cirugía , Femenino , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Hueso Occipital/patología , Embarazo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
10.
Yakugaku Zasshi ; 116(10): 783-91, 1996 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-8950870

RESUMEN

The antagonism of histamine H2-receptor by SWR-104SA (1'-bromo-N-[3-[3-(1-piperidinylmethyl) phenoxy] propyl]-spiro [1,3-dioxolane-2,9'-pentacyclo-[4.3.0.0.(2,5)0.(3,8) 0.(4,7)]nonane]-4'-carboxamide monooxalate) was estimated using the isolated guinea-pig atrium and gastric acid secretion in rats. The concentration-response curves for the positive chronotropic effect of histamine on the atrium were displaced to the right in parallel without change in the maximum response by SWR-104SA and roxatidine acetate hydrochloride (roxatidine). The pA2 values of SWA-104SA and roxatidine acetate hydrochloride were 7.27 and 7.38, respectively. The slopes of the regression line of log (DR-1) against log SWR-104SA and roxatidine concentration were 1.00 and 0.92, respectively. There was no significant difference between the two compounds with respect to the histamine H2-receptor antagonism and/or binding manner in vitro. In the rat gastric fistula model stimulated by histamine, however, antisecretory potency of SWR-104SA was 3 times less than that of roxatidine. SWR-104SA given p.o. prevented the formation of gastric lesion induced by HCl-ethanol and indomethacin dose-dependently, roxatidine also prevented its formation by HCl-ethanol, but failed to prevent that by indomethacine. These antiulcer activities of SWR-104SA were shown at the lesser doses of antisecretory activity. On the other hand, roxatidine did not prevent the ulcer formation at the same dose level of antisecretory activity. These results indicate that the antiulcer effect of SWR-104SA is not caused by the antisecretory action alone. In addition, the mucosal protective activity of SWR-104SA for HCl-ethanol induced gastric lesion was independent of endogenous prostaglandins. Moreover SWR-104SA had inhibitory effects on indomethacin-induced gastric hypermotility in rats. These actions may partly explain the gastric protection of this compound and additional mechanisms such as mucosal blood flow could be involved in the antiulcer efficacy. Consequently, it appears that SWR-104SA is a new antiulcer drug that exerts a potent cytoprotective effect in addition to its gastric antisecretory activity.


Asunto(s)
Dioxolanos/farmacología , Ácido Gástrico/metabolismo , Antagonistas de los Receptores H2 de la Histamina/farmacología , Compuestos de Espiro/farmacología , Úlcera Gástrica/prevención & control , Animales , Etanol , Motilidad Gastrointestinal/efectos de los fármacos , Cobayas , Antagonistas de los Receptores H2 de la Histamina/uso terapéutico , Ácido Clorhídrico , Indometacina , Masculino , Ratas , Ratas Sprague-Dawley , Úlcera Gástrica/inducido químicamente
11.
Gan To Kagaku Ryoho ; 24(8): 965-9, 1997 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-9212805

RESUMEN

Eleven inoperable patients with advanced esophageal carcinoma were treated with chemotherapy (carboplatin, 5-FU, vindesine) and concomitant radiotherapy. Two patients (T2) received this treatment due to their poor general condition and refusal of operation, and 9 patients for infiltration of tumor into the adjacent organs (T4). Administration of carboplatin (30 mg/body) and 5-FU (250 mg/body) together with radiotherapy (1.8 Gy/d) for 5 days a week was performed. This chemoradiation therapy was carried out for 5 consecutive weeks. In addition, vindesine (1-3 mg/body) was administered in the 1st and 4th week. After evaluation, endoscopic balloon dilatation was performed in 6 patients with stenosis of the esophagus. The general response rate was 80%. CR was noted in 2 patients of T2 but 1 patient of T4 developed severe leucopenia and immunosuppression, and died of septic MOF. All but the MOF case could take enough food orally following the endoscopic dilatation. The 1-year survival rate in the T4 group (45%) was significantly better than the non-treatment group (0%). In conclusion, this treatment is beneficial for patients with inoperable esophageal carcinoma to obtain a satisfactory QOL and survival rate.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Esofágicas/terapia , Anciano , Carboplatino/administración & dosificación , Cateterismo , Terapia Combinada , Esquema de Medicación , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/radioterapia , Femenino , Fluorouracilo/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Dosificación Radioterapéutica , Tasa de Supervivencia , Vindesina/administración & dosificación
12.
Fukuoka Igaku Zasshi ; 81(2): 71-6, 1990 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-2328937

RESUMEN

Autonomic nerve dysfunction in patients with chronic renal failure has of late become an issue to be investigated. R-R intervals in resting electrocardiograms were measured to evaluate activities of the cardiac parasympathetic nerve system. A total of 140 patients with chronic renal failure were studied to be compared with 20 normal controls (cont.) and 39 with diabetes mellitus (DM). Of these patients 15 were subjected to conservative treatment (CRF), while 125 patients were undergoing hemodialysis due to chronic renal failure-100 of them derived from chronic glomerulonephritis (HD) and 25 from diabetes mellitus (DM.HD). The variation coefficient of the R-R interval (CVRR) was measured after the subject patients had rested for over 15 minutes before a dialysis session. The mean CVRR were 2.15 +/- 1.25% in CRF group, 2.36 +/- 1.37% in HD and 1.37 +/- 0.99% in DM.HD. These values were significantly lower than in control group (4.70 +/- 2.64%). On the other hand, the value in DM.HD group, as shown above, was significantly lower than in HD. In CRF group the CVRR values lowered as residual renal functions decreased. No significant correlations between CVRR S and the duration of hemodialysis treatment were noted among the groups. In HD group the CVRR S were significantly lower in patients with hypotensive tendency during hemodialysis than in those who enjoyed good control of blood pressure. These results suggest that the measurement of CVRR S can be of help in evaluating autonomic nerve dysfunction in patients with chronic renal failure.


Asunto(s)
Electrocardiografía , Corazón/inervación , Fallo Renal Crónico/fisiopatología , Sistema Nervioso Parasimpático/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
13.
Shinrigaku Kenkyu ; 67(5): 367-74, 1996 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-9121009

RESUMEN

This study addressed people's judgments about desirability of various reward allocation under different task-rules aggregating individual inputs to a group outcome. The rules used in the study were additive, conjunctive, and disjunctive (Steiner, 1972), and subjects evaluated twelve cases of reward allocation reflecting different distributive principles, such as equality and equity. It was found that no one principle was favored under all three aggregation rules. Generally, a distributive principle was favored that was most beneficial for the member whose input 'determined' group success. Specifically, equality was endorsed most often under the conjunctive rule, and equity under the disjunctive rule. It was also found that the Pareto axiom was frequently violated. In pairwise comparison, more than 60% of the subjects endorsed an allocation scheme, that was, subjectively fairer but objectively inferior in terms of Pareto optimality, revealing their commitment to a specific distributive principle. The results suggest that the universal economic assumption of Pareto optimality for social policy-making be seriously questioned.


Asunto(s)
Juicio , Recompensa , Deseabilidad Social , Justicia Social , Adulto , Femenino , Humanos , Masculino , Personalidad , Formulación de Políticas , Política Pública , Análisis y Desempeño de Tareas
14.
Nihon Saikingaku Zasshi ; 44(6): 797-803, 1989 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-2533624

RESUMEN

A mycolic acid-containing glycolipid, trehalose-2,3,6'-trimycolate (GaGM), derived from Gordona aurantiaca, an acid-fast bacteria closely related taxonomically to Mycobacterium, was investigated for its immune adjuvant activity in vitro. The liposomes containing GaGM showed strong mitogenic effects on murine spleen cells at the doses used (25-100 micrograms/ml), but not on T-cell-depleted spleen cells or macrophage-depleted spleen cells. These results suggest that the mitogenic property of liposomes containing GaGM differs from that of such as lipopolysaccharide, a B-cell mitogen and that its mitogenic effects depend on the presence of macrophages. In addition, liposomes containing GaGM augmented the mixed lymphocyte reaction (MLR) and in vitro induction of cytotoxic T-lymphocytes (CTLs) against allogeneic tumor cells. These results suggest that liposomes containing GaGM have immune adjuvant properties in vitro and the adjuvant activity may be related to such cytokines as interleukin-1 and -2.


Asunto(s)
Adyuvantes Inmunológicos , Glucolípidos/farmacología , Activación de Linfocitos/efectos de los fármacos , Mycobacterium/análisis , Linfocitos T Citotóxicos/inmunología , Animales , Células Cultivadas , Glucolípidos/aislamiento & purificación , Liposomas/inmunología , Prueba de Cultivo Mixto de Linfocitos , Macrófagos/inmunología , Masculino , Ratones , Bazo/citología
15.
Nihon Saikingaku Zasshi ; 44(2): 533-9, 1989 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-2788754

RESUMEN

A mycolic acid-containing glycolipid, trehalose-2,3,6'-trimycolate (GaGM), derived from Gordona aurantiaca, an acid-fast bacterium closely related taxonomically to Mycobacterium, was investigated for its immune adjuvant activity on cell-mediated responses in the mouse. I.V. injection of liposomes containing GaGM enhanced the generation of cytotoxic T-lymphocyte (CTL) against syngeneic and allogeneic tumor cells. In addition, the injection of GaGM augmented the natural killer (NK) activity and the antibody-dependent cellular cytotoxicity (ADCC). These results suggest that the injection of GaGM induces the production of interleukin-2 (IL-2), since such effector cells as CTL, NK and K cells have been shown to require IL-2 for their development.


Asunto(s)
Adyuvantes Inmunológicos , Glucolípidos/farmacología , Células Asesinas Naturales/inmunología , Mycobacterium/análisis , Animales , Citotoxicidad Celular Dependiente de Anticuerpos/efectos de los fármacos , Células Cultivadas , Glucolípidos/aislamiento & purificación , Interleucina-2/biosíntesis , Activación de Linfocitos/efectos de los fármacos , Ratones
16.
Genome Announc ; 1(3)2013 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-23682148

RESUMEN

γ-Hexachlorocyclohexane (γ-HCH) is a man-made chlorinated insecticide that has caused serious environmental problems. Here, we report the complete genome sequence of the γ-HCH-degrading bacterium Sphingomonas sp. strain MM-1, which consists of one chromosome and five plasmids. All the specific lin genes that are almost identical to those of Sphingobium japonicum UT26 for the conversion of γ-HCH to ß-ketoadipate are dispersed on four out of the five plasmids.

17.
J Phys Condens Matter ; 24(9): 092001, 2012 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-22301685

RESUMEN

We show that a metallic surface state is formed on Tl/Ge(111)-(1 × 1). The surface state forms electron pockets around K of the surface Brillouin zone. A first-principles calculation reveals that the electron pockets are composed of a single branch of a spin-split surface-state band. The spin quantization axis is along the surface normal and inverts according to the time-reversal symmetry. Since this spin-split branch is the unique metallic band on this surface, the surface conductivity should be governed by this spin-split branch, suggesting a possible spin-polarized electric current.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón , Germanio/química , Marcadores de Spin , Talio/química , Propiedades de Superficie
19.
Nihon Seikeigeka Gakkai Zasshi ; 66(1): 83-91, 1992 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-1548444

RESUMEN

The author investigated the influence of sexual glands and testosterone on the incidence of femoral head lesions, those are osteonecrosis or ossification disturbance in the femoral heads, of spontaneously hypertensive rats (SHR). The rats were divided into the following six experimental groups: 1) untreated males (I M group); 2) castrated males (II M group); 3) castrated males treated with testosterone (III M group); 4) untreated females (I F group); 5) ovariectomized females (II F group); and 6) ovariectomized females treated with testosterone (III F group). We then compared the incidence of lesions in the 20 femoral heads in each group. There were 18, 5, 16, 6, 9, and 10 lesions in the I M, II M, III M, I F, II F and III F groups, respectively. The incidence was remarkably high in the I M group and III M group. Moreover, the incidence of abnormal findings in the growth plate of the femoral heads showed a pattern similar to that of the femoral head lesions. The above findings suggest a difference in the incidence of femoral head lesions between the sexes results from the effect of testosterone on the growth plate.


Asunto(s)
Necrosis de la Cabeza Femoral/epidemiología , Caracteres Sexuales , Animales , Femenino , Necrosis de la Cabeza Femoral/patología , Placa de Crecimiento/fisiología , Masculino , Ratas , Ratas Endogámicas SHR , Testosterona/fisiología
20.
Biol Pharm Bull ; 22(7): 745-8, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10443477

RESUMEN

To investigate the effects of vasoactive intestinal peptide (VIP) on Cl- transport across normal human bronchial epithelial (NHBE) cells grown in a monolayer, changes in short-circuit current (Isc) were measured in Ussing chamber systems. In the presence of 10(-4) M amiloride, the addition of VIP to the serosal solution led to an increase in the Isc in a concentration-dependent manner, the 50% effective concentration (EC50) being 2.6 x 10(-11) M. However, the addition of 10(-5) M forskolin had little effect on the increase in Isc. On the other hand, in the intracellular cAMP measurement, 10(-5) M forskolin remarkably increased the cAMP levels, but 10(-7) M VIP did not. This result suggests that Cl- secretion by VIP is not related to the raised intracellular cAMP levels in NHBE cells.


Asunto(s)
Bronquios/metabolismo , Cloruros/metabolismo , Péptido Intestinal Vasoactivo/metabolismo , Bronquios/citología , Células Cultivadas , AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Células Epiteliales/metabolismo , Humanos
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