Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 157
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Clin Genet ; 94(2): 232-238, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29700822

RESUMEN

Leukoencephalopathies encompass all clinical syndromes that predominantly affect brain white matter. Genetic diagnosis informs clinical management of these patients, but a large part of the genetic contribution to adult leukoencephalopathy remains unresolved. To examine this genetic contribution, we analyzed genomic DNA from 60 Japanese patients with adult leukoencephalopathy of unknown cause by next generation sequencing using a custom-designed gene panel. We selected 55 leukoencephalopathy-related genes for the gene panel. We identified pathogenic mutations in 8 of the 60 adult leukoencephalopathy patients (13.3%): NOTCH3 mutations were detected in 5 patients, and EIF2B2, CSF1R, and POLR3A mutations were found independently in 1 patient each. These results indicate that cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) caused by NOTCH3 mutations is the most frequent adult leukoencephalopathy in our cohort. Moreover, brain imaging analysis indicates that CADASIL patients who do not present typical phenotypes may be underdiagnosed if not examined genetically.


Asunto(s)
CADASIL/genética , Predisposición Genética a la Enfermedad , Leucoencefalopatías/genética , Receptor Notch3/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , CADASIL/diagnóstico por imagen , CADASIL/fisiopatología , Estudios de Cohortes , Factor 2B Eucariótico de Iniciación/genética , Pruebas Genéticas , Humanos , Leucoencefalopatías/diagnóstico por imagen , Leucoencefalopatías/fisiopatología , Imagen por Resonancia Magnética , Persona de Mediana Edad , Mutación , Fenotipo , ARN Polimerasa III/genética , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Secuenciación del Exoma
2.
J Clin Pharm Ther ; 39(5): 573-6, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24989642

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Drug-induced liver injury (DILI) is a leading cause of acute liver failure in developed countries. Hepatotoxicity is a well-recognized adverse effect associated with synthetic oestrogens, which can cause cholestasis. The current report describes ethinyloestradiol (EE2)-associated highly unusual adverse effects of autoimmune hepatitis (AIH) and microvesicular steatosis (MS). DILI that fulfils the criteria for AIH is referred to as drug-induced autoimmune hepatitis (DIAIH). MS is a potentially severe liver lesion that results from mitochondrial dysfunction. We explore the pathophysiological mechanisms underlying DIAIH and MS. CASE SUMMARY: A 51-year-old woman presented with jaundice, increased liver enzymes and IgG, and positive ANA. She had been taking EE2 for 3 years. Liver biopsy showed prominent interface hepatitis with MS. A drug-lymphocyte stimulation test (DLST) using EE2 was positive. The liver biochemical parameters had normalized after the EE2 discontinuation; however, they exacerbated 5 months post-onset. Repeated liver biopsy showed interface hepatitis with no MS. Considering EE2-induced DIAIH, corticosteroids treatment was initiated. Then, all liver biochemical parameters had normalized, and the corticosteroids were successfully withdrawn. The patient continued to be in complete remission over the next 3 years. WHAT IS NEW AND CONCLUSION: Five remarkable points should be emphasized: (i) a long latency interval, despite the acute presentation; (ii) exacerbation of liver biochemical parameters, even after drug cessation; (iii) the paired liver biopsies indicating continuing inflammation and disappearance of toxic features; (iv) a positive DLST and the absence of fibrosis consistent with DIAIH and not AIH; and (v) a rare histological feature of MS. Intense immunoallergic reactions were likely triggers of MS in the current case. A possibility of DIAIH should be considered in cases of DILI which exhibit overt jaundice, autoantibodies, intense histological inflammation and a long latency period.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Etinilestradiol/efectos adversos , Hígado Graso/diagnóstico , Hepatitis Autoinmune/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Diagnóstico Diferencial , Hígado Graso/sangre , Hígado Graso/inducido químicamente , Femenino , Hepatitis Autoinmune/sangre , Humanos , Persona de Mediana Edad
3.
Nature ; 405(6789): 929-32, 2000 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-10879529

RESUMEN

The realization of all-optical switching, modulating and computing devices is an important goal in modern optical technology. Nonlinear optical materials with large third-order nonlinear susceptibilities (chi(3)) are indispensable for such devices, because the magnitude of this quantity dominates the device performance. A key strategy in the development of new materials with large nonlinear susceptibilities is the exploration of quasi-one-dimensional systems, or 'quantum wires'--the quantum confinement of electron-hole motion in one-dimensional space can enhance chi(3). Two types of chemically synthesized quantum wires have been extensively studied: the band insulators of silicon polymers, and Peierls insulators of pi-conjugated polymers and platinum halides. In these systems, chi(3) values of 10(-12) to 10(-7) e.s.u. (electrostatic system of units) have been reported. Here we demonstrate an anomalous enhancement of the third-order nonlinear susceptibility in a different category of quantum wires: one-dimensional Mott insulators of 3d transition-metal oxides and halides. By analysing the electroreflectance spectra of these compounds, we measure chi(3) values in the range 10(-8) to 10(-5) e.s.u. The anomalous enhancement results from a large dipole moment between the lowest two excited states of these systems.

4.
Nat Commun ; 11(1): 4138, 2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-32811820

RESUMEN

Charge acceleration during an intense light field application to solids attracts much attention as elementary processes in high-harmonic generation and photoelectron emission. For manipulating such attosecond dynamics of charge, carrier-envelope-phase (CEP: relative phase between carrier oscillation of light field and its envelope function) control has been employed in insulators, nanometal and graphene. In superconducting materials, collective control of charge motion is expected because of its strongly coherent nature of quasi-particles. Here we report that, in a layered organic superconductor, a non-linear petahertz current driven by a single-cycle 6 femtosecond near infrared field shows up as second harmonic generation (SHG), which is in contrast to the common belief that even harmonics are forbidden in the centrosymmetric system. The SHG represents a CEP sensitive nature and an enhancement near the superconducting temperature. The result and its quantum many-body analysis indicate that a polarized current is induced by non-linear acceleration of charge, which is amplified by superconducting fluctuations. This will lead to petahertz functions of superconductors and of strongly correlated systems.

5.
Food Chem Toxicol ; 46(7): 2349-57, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18448224

RESUMEN

Licorice flavonoid oil (LFO) is a new functional food ingredient consisting of licorice hydrophobic polyphenols in medium-chain triglycerides (MCT). As part of a safety evaluation, a 90-day oral toxicity study in rats was conducted using an LFO concentrate solution (2.90% glabridin). Male and female animals were assigned to one of 12 groups (10 males or females per group) and received corn oil (negative control), MCT (vehicle control), or 400, 600, 800 or 1600 mg/kg of the LFO concentrate solution. In conclusion, LFO concentrate solution induced an anticoagulation effect in both sexes, although there was a clear sex difference. Based on these findings, it is concluded that the no-observed-adverse-effect level (NOAEL) for the LFO concentrate solution is estimated to be 800 mg/kg/day for female rats, and approximately 400 mg/kg/day for male rats.


Asunto(s)
Flavonoides/toxicidad , Glycyrrhiza/química , Aceites de Plantas/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Nivel sin Efectos Adversos Observados , Distribución Aleatoria , Ratas , Factores Sexuales , Organismos Libres de Patógenos Específicos , Pruebas de Toxicidad
6.
Sci Rep ; 8(1): 15014, 2018 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-30301914

RESUMEN

Rapid polarization control by an electric field in ferroelectrics is important to realize high-frequency modulation of light, which has potential applications in optical communications. To achieve this, a key strategy is to use an electronic part of ferroelectric polarization. A hydrogen-bonded molecular ferroelectric, croconic acid, is a good candidate, since π-electron polarization within each molecule is theoretically predicted to play a significant role in the ferroelectric-state formation, as well as the proton displacements. Here, we show that a sub-picosecond polarization modulation is possible in croconic acid using a terahertz pulse. The terahertz-pulse-pump second-harmonic-generation-probe and optical-reflectivity-probe spectroscopy reveal that the amplitude of polarization modulation reaches 10% via the electric-field-induced modifications of π-electron wavefunctions. Moreover, the measurement of electric-field-induced changes in the infrared molecular vibrational spectrum elucidates that the contribution of proton displacements to the polarization modulation is negligibly small. These results demonstrate the electronic nature of polarization in hydrogen-bonded molecular ferroelectrics. The ultrafast polarization control via π-electron systems observed in croconic acid is expected to be possible in many other hydrogen-bonded molecular ferroelectrics and utilized for future high-speed optical-modulation devices.

8.
Kyobu Geka ; 60(11): 1022-6, 2007 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-17926908

RESUMEN

Two episode of junctional ectopic tachycardia (JET) caused hemodynamic deterioration early after tetralogy of Fallot repair in an 8-month-old infant. Sinus rhythm resumed in each of the episodes immediately after intravenous administration of nifekalant hydrochloride (NIF), a newly developed Vaughan-Williams class III antiarrhythmic drug in Japan. Although QT interval was modestly prolonged with NIF, no life-threatening ventricular arrhythmia (i.e., torsades de pointes) occurred. NIF might be an effective alternative in the treatment of postoperative JET in congenital cardiac surgery.


Asunto(s)
Antiarrítmicos/uso terapéutico , Complicaciones Posoperatorias/tratamiento farmacológico , Pirimidinonas/uso terapéutico , Taquicardia Ectópica de Unión/tratamiento farmacológico , Tetralogía de Fallot/cirugía , Humanos , Lactante , Masculino , Taquicardia Ectópica de Unión/etiología
9.
Cancer Res ; 58(20): 4548-51, 1998 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-9788598

RESUMEN

Male Wistar rats were fed a choline-deficient, L-amino acid-defined (CDAA) diet alone or in combination with a nitrone-based free radical trapping agent, phenyl N-tert-butyl nitrone (PBN) in the drinking water at the concentrations of 0.013, 0.065, and 0.130% for 12 weeks. PBN inhibited the changes that are normally induced in the livers of rats by the CDAA diet feeding, i.e., development of putative preneoplastic lesions, proliferation of connective tissue, reduction of glutathione S-transferase activity, formation of 8-hydroxyguanine in DNA, and an increase in inducible cyclo-oxygenase (COX2) activity. PBN, however, did not prevent the increases in the COX2 mRNA or protein levels brought on by the CDAA diet These results indicate that the loss of glutathione S-transferase activity and COX2 induction may play significant roles in rat liver carcinogenesis by the CDAA diet and that PBN prevents neoplasia not only by its radical scavenging activity but also by inhibiting COX2 activity at the catalytic level.


Asunto(s)
Aminoácidos/deficiencia , Deficiencia de Colina/complicaciones , Depuradores de Radicales Libres/farmacología , Neoplasias Hepáticas Experimentales/prevención & control , Óxidos de Nitrógeno/farmacología , Animales , Óxidos N-Cíclicos , Ciclooxigenasa 2 , Glutatión/metabolismo , Isoenzimas/efectos de los fármacos , Neoplasias Hepáticas Experimentales/etiología , Masculino , FN-kappa B/fisiología , Óxido Nítrico Sintasa/fisiología , Óxido Nítrico Sintasa de Tipo II , Prostaglandina-Endoperóxido Sintasas/efectos de los fármacos , Ratas , Ratas Wistar
10.
J Am Coll Cardiol ; 35(3): 655-65, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10716468

RESUMEN

OBJECTIVES: To determine the effect of macrophage colony-stimulating factor (MCSF) on atherogenesis in patients with coronary artery disease (CAD), we assessed the relation between the plasma concentration of MCSF and the incidence of acute coronary events in patients with CAD. BACKGROUND: Cytokines such as MCSF play a central role in inflammatory and proliferative responses in patients with acute coronary syndromes. However, the effect of MCSF on the clinical course in patients with CAD is still not known. METHODS: We measured the plasma MCSF concentration in 142 patients with documented CAD (62 +/- 9 years) and followed up for a mean period of 14 +/- 6 months. The study included 97 patients with stable angina (SA), 45 patients with unstable angina (UA) and 22 age-matched control subjects. The predictors of coronary events were analyzed by using a Cox proportional hazards model. RESULTS: The mean plasma MCSF concentration in patients with UA was significantly higher than that in patients with SA and in control subjects (981 +/- 277 vs. 693 +/- 223 vs. 680 +/- 158 pg/ml, p < 0.001). The mean plasma MCSF concentration in the 20 patients with coronary events was significantly higher than that in patients without coronary events (1,192 +/- 232 vs. 690 +/- 213 pg/ml, p < 0.001). The predictors of unfavorable outcome were an increased MCSF concentration, the presence of CAD and a low ejection fraction. CONCLUSIONS: These findings suggest that an increased circulating MCSF concentration reflects atherosclerotic progression in patients with CAD and predicts future cardiac events.


Asunto(s)
Angina de Pecho/sangre , Factor Estimulante de Colonias de Macrófagos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Angina de Pecho/diagnóstico por imagen , Angina de Pecho/terapia , Angioplastia Coronaria con Balón , Biomarcadores/sangre , Angiografía Coronaria , Puente de Arteria Coronaria , Progresión de la Enfermedad , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Volumen Sistólico
11.
Clin Pharmacol Ther ; 42(2): 166-74, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2955996

RESUMEN

The effect of nicorandil, a new coronary vasodilator, was evaluated in 32 patients with variant angina pectoris in a single-blind trial. The study was comprised of a pretreatment period of 2 days with a placebo, a 3-day nicorandil medication period (20 mg/day), and a 2-day posttreatment period with the placebo. Anginal attacks disappeared completely in 24 of the 32 patients. The number of attacks during the pretreatment period, 3.6 +/- 0.4 per day, became significantly reduced to 0.7 +/- 0.2 per day during nicorandil therapy (P less than 0.001) and significantly increased to 1.3 +/- 0.3 per day after withdrawal of the drug (P less than 0.05). In 17 patients with continuous ECG monitoring, the frequency of occurrence of ST-segment elevation was 8.6 +/- 2.7 per day during the preobservation period, significantly decreased to 0.4 +/- 0.2 per day during nicorandil therapy (P less than 0.01), and significantly increased to 1.9 +/- 0.7 per day after withdrawal of the drug (P less than 0.05). The results demonstrate the effectiveness of nicorandil in the treatment of variant angina pectoris.


Asunto(s)
Angina Pectoris Variable/tratamiento farmacológico , Niacinamida/análogos & derivados , Vasodilatadores/uso terapéutico , Ensayos Clínicos como Asunto , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Niacinamida/farmacología , Niacinamida/uso terapéutico , Nicorandil , Factores de Tiempo , Vasodilatadores/farmacología
12.
Neuroscience ; 117(2): 373-81, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12614677

RESUMEN

Syntrophin is an adaptor protein that binds signaling molecules to the dystrophin-associated protein complex, which connects extracellular matrix to intracellular cytoskeleton for construction and maintenance of the postsynaptic structures in the neuromuscular junction and the CNS. Among these signaling molecules, a family of microtubule-associated serine/threonine kinases has a unique structural feature with a serine/threonine kinase domain and a postsynaptic density protein-95/discs large/zona occludens-1 domain. In the present study, we identified syntrophin-associated serine/threonine kinase-124, a novel splice variant of the syntrophin-associated serine/threonine kinase which is a member of the microtubule-associated serine/threonine kinases family. Comparing to the original clone (syntrophin-associated serine/threonine kinase-170), syntrophin-associated serine/threonine kinase-124 is truncated just downstream of the postsynaptic density protein-95/discs large/zona occludens-1 domain. Using a monoclonal antibody specifically recognizing syntrophin-associated serine/threonine kinase-124, strong expression of the protein was observed in neurons of the subventricular zone and granule cells of the olfactory bulb, Islands of Calleja, hippocampal dentate gyrus and cerebellum. syntrophin-associated serine/threonine kinase-124 is selectively localized in the nuclei of neurons and distinct from syntrophin-associated serine/threonine kinase-170, which is interacting with syntrophin on the cell surface. Considering the tissue and subcellular distributions of syntrophin-associated serine/threonine kinase-124, it is suggested that syntrophin-associated serine/threonine kinase-124 may have functions in transcriptional regulation for the features commonly shared by these neurons. On the other hand, syntrophin-associated serine/threonine kinase-124 was also localized in glia-like cell bodies in the corpus callosum and fiber bundles in the spinal trigeminal and solitary tracts, suggesting syntrophin-associated serine/threonine kinase-124 may have other functions in these types of cells.


Asunto(s)
Encéfalo/metabolismo , Proteínas Asociadas a la Distrofina , Proteínas de la Membrana/metabolismo , Proteínas Musculares/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Secuencia de Aminoácidos/fisiología , Animales , Encéfalo/enzimología , ADN Recombinante/biosíntesis , ADN Recombinante/genética , Masculino , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/genética , Proteínas Musculares/biosíntesis , Proteínas Musculares/genética , Proteínas Serina-Treonina Quinasas/biosíntesis , Proteínas Serina-Treonina Quinasas/genética , Ratas , Ratas Wistar
13.
Am J Cardiol ; 49(8): 2030-6, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6211085

RESUMEN

A negative U wave is highly specific for the presence of heart disease and is associated with other electrocardiographic abnormalities in more than 90 percent of patients. The three most common conditions associated with a negative U wave are systemic hypertension, aortic and mitral regurgitation and ischemic heart disease. The U wave vector is directed opposite to the QRS axis in the horizontal plane in patients with both left and right ventricular hypertrophy. In patients with ischemic heart disease, the U wave vector tends to be directed away from the site of the akinetic or dyskinetic region. The change from a negative to an upright U wave after a reduction in blood pressure, renal transplantation, insertion of a valve prosthesis or a coronary arterial bypass graft procedure is associated with a decrease in the QRS amplitude but with no consistent changes in T wave polarity. The timing of the U wave apex is dependent on the duration of ventricular repolarization but not on the duration of the QRS complex. This finding and other electrocardiographic observations are explained better by the ventricular relaxation than by the Purkinje fiber repolarization theory of U wave genesis.


Asunto(s)
Electrocardiografía , Cardiopatías/diagnóstico , Insuficiencia de la Válvula Aórtica/diagnóstico , Bloqueo de Rama/diagnóstico , Cardiomegalia/diagnóstico , Enfermedad Coronaria/diagnóstico , Cardiopatías Congénitas/diagnóstico , Humanos , Hipertensión/diagnóstico , Insuficiencia de la Válvula Mitral/diagnóstico , Infarto del Miocardio/diagnóstico , Ramos Subendocárdicos/fisiopatología
14.
Am J Cardiol ; 84(5): 608-11, A9, 1999 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10482168

RESUMEN

Cardiac troponin T, measured by second-generation assay, is a highly sensitive and specific marker of minor myocardial damage. Cardiac troponin T was elevated in patients with severe chronic heart failure; it identifies those with latent and progressive myocardial damage and those who are at increased risk of cardiac events.


Asunto(s)
Insuficiencia Cardíaca/diagnóstico , Troponina T/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico , Valor Predictivo de las Pruebas , Valores de Referencia
15.
Brain Res Mol Brain Res ; 45(1): 117-26, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9105677

RESUMEN

Nociceptin/orphanin FQ is a heptadecapeptide which was recently isolated from brains. It induces hyperalgesia, in contrast to the analgesic effects of opioid ligands, although it and its receptor structurally resemble opioid peptides and opioid receptors, respectively. To investigate the molecular mechanism underlying nociceptin/orphanin FQ actions, we performed Xenopus oocyte expression assays, in situ hybridization histochemistry and electrophysiological analyses of neurons. We found that the nociceptin/orphanin FQ receptor is functionally coupled with the G-protein-activated K+ (GIRK) channel in Xenopus oocytes, and that the receptor mRNA and GIRK1 mRNA co-exist in various neurons, including hippocampal pyramidal cells. Furthermore, we found that nociceptin/orphanin FQ induces hyperpolarizing currents via inward-rectifier K+ channels in hippocampal pyramidal cells, suggesting that the nociceptin/orphanin FQ receptor couples with the GIRK channel in this region. We conclude that the nociceptin/orphanin FQ receptor couples with the GIRK channel in various neurons, including hippocampal pyramidal cells, thereby modulating neuronal excitability.


Asunto(s)
Endorfinas/farmacología , Hipocampo/fisiología , Péptidos Opioides/farmacología , Canales de Potasio de Rectificación Interna , Canales de Potasio/fisiología , Receptores Opioides/fisiología , Animales , Cartilla de ADN , Canales de Potasio Rectificados Internamente Asociados a la Proteína G , Humanos , Potenciales de la Membrana/efectos de los fármacos , Neuronas/fisiología , Oocitos/fisiología , Péptidos Opioides/metabolismo , Reacción en Cadena de la Polimerasa , Potasio/farmacología , Canales de Potasio/biosíntesis , Células Piramidales/fisiología , Ratas , Receptores Opioides/biosíntesis , Proteínas Recombinantes/biosíntesis , Xenopus laevis , Receptor de Nociceptina , Nociceptina
16.
Toxicol Sci ; 80(1): 109-14, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15014208

RESUMEN

Until recently it has been generally considered that genotoxic carcinogens have no threshold in exerting their potential for cancer induction. However, the nonthreshold theory can be challenged with regard to assessment of cancer risk to humans. In the present study we show that a food derived, genotoxic hepatocarcinogen, 2-amino-1-methyl-6-phenolimidazo[4,5-b]pyridine (PhIP), does not induce aberrant crypt foci (ACF) as preneoplastic lesions at low dose (below 50 ppm) or 8-hydroxy-2'-deoxyguanosine (below 400 ppm) in the rat colon. Moreover PhIP-DNA adducts were not formed at the lowest dose (below 0.01 ppm). Thus, the dose required to initiate ACF is approximately 5000 times higher than that needed for adduct formation. The results imply a no-observed effect level (existence of a threshold) for colon carcinogenesis by a genotoxic carcinogen.


Asunto(s)
Carcinógenos/toxicidad , Colon/efectos de los fármacos , Desoxiguanosina/análogos & derivados , Imidazoles/toxicidad , Mutágenos/toxicidad , 8-Hidroxi-2'-Desoxicoguanosina , Animales , Carcinógenos/administración & dosificación , Colon/metabolismo , Colon/patología , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/patología , Aductos de ADN/biosíntesis , Aductos de ADN/metabolismo , Desoxiguanosina/metabolismo , Relación Dosis-Respuesta a Droga , Imidazoles/administración & dosificación , Imidazoles/metabolismo , Masculino , Pruebas de Mutagenicidad , Mutágenos/administración & dosificación , Nivel sin Efectos Adversos Observados , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/patología , Ratas , Ratas Endogámicas F344
17.
Neurosci Lett ; 172(1-2): 119-21, 1994 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-8084514

RESUMEN

The electrophysiological effects of KST-5452 [3-(m-phenoxybenzylidene)-quinuclidine], an M1 muscarinic acetylcholine receptor (muscarinic AChR) binding compound, were studied in NG108-15 neuroblastoma x glioma hybrid cells transfected with m1 muscarinic AChR cDNA. Application of KST-5452 to m1-transformed NGPM1-27 cells elicited a sustained inward current associated with decreased conductance and reduced M-current relaxations at a holding potential of -20 mV. The KST-5452-induced responses were blocked by pirenzepine, suggesting that KST-5452 acts as a potent excitant via M1 muscarinic AChRs in brain neurons.


Asunto(s)
Compuestos de Bencilideno/farmacología , Cognición/efectos de los fármacos , Canales de Potasio/metabolismo , Quinuclidinas/farmacología , Receptores Muscarínicos/efectos de los fármacos , Acetilcolina/farmacología , Animales , Compuestos de Bencilideno/antagonistas & inhibidores , Línea Celular Transformada , Electrofisiología , Potenciales de la Membrana/efectos de los fármacos , Pirenzepina/farmacología , Canales de Potasio/efectos de los fármacos , Quinuclidinas/antagonistas & inhibidores , Ratas , Células Tumorales Cultivadas
18.
Int J Cardiol ; 35(1): 65-70, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1563881

RESUMEN

Circadian variation of ischemic threshold in chronic stable exertional angina was determined in 51 patients with documented coronary artery disease from the Holter monitor results. The peak favored time zones of ischemic attacks were 8 a.m. and 9 a.m. There was no difference in frequency of ischemic attacks, magnitude of ST-segment depression, or duration of ST-segment depression between the two time zones for ischemic attacks, 6-9 a.m. and 0-3 p.m., but the ischemic threshold was lower in the morning than in the afternoon. These observations suggest that the pathogenesis of ischemic attacks differs from one time zone to the other and is considered helpful in planning therapeutic strategies for myocardial ischemia.


Asunto(s)
Angina de Pecho/fisiopatología , Ritmo Circadiano , Actividades Cotidianas , Adulto , Anciano , Enfermedad Coronaria/fisiopatología , Electrocardiografía Ambulatoria , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Miocardio/metabolismo , Consumo de Oxígeno
19.
Int J Cardiol ; 14(1): 47-53, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3804504

RESUMEN

Human leucocyte antigen analysis of 45 patients with variant angina was performed to determine the presence of causative genetic factor(s). A significantly low frequency of human leucocyte antigen DQ omega 3 was found in these patients, as compared with that in 152 normal Japanese adults. There were no differences in frequencies of antigens between patients with normal and those with atherosclerotic coronaries. These data suggest that some genetic factor(s) may contribute to the pathogenesis of coronary spasm.


Asunto(s)
Angina Pectoris Variable/genética , Antígenos de Histocompatibilidad/genética , Angina Pectoris Variable/sangre , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/genética , Vasos Coronarios/anatomía & histología , Femenino , Antígenos de Histocompatibilidad/análisis , Humanos , Japón , Masculino
20.
J Antibiot (Tokyo) ; 39(7): 985-93, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3759652

RESUMEN

The gene for an extracellular xylanase from Streptomyces sp. No. 36a was cloned into Streptomyces lividans TK21 using pIJ702 as a vector plasmid. The smallest DNA fragment encoding the xylanase gene and its possible promotor was determined to be a 1.04 kb Sph I-Sac I fragment by sub-cloning studies. This xylanase gene fragment was transferred into the pSK2 series of plasmids and introduced into Streptomyces kasugaensis G3 protoplasts. The cloned xylanase gene was expressed in both S. lividans TK21 and S. kasugaensis G3, and these clones produced and secreted high yields of xylanase into the culture medium. The xylanase production was not detected when a foreign DNA fragment was inserted into the Bcl I site locating in the xylanase gene fragment.


Asunto(s)
Clonación Molecular , Glicósido Hidrolasas/genética , Streptomyces/genética , Vectores Genéticos , Glicósido Hidrolasas/biosíntesis , Plásmidos , Streptomyces/enzimología , Xilano Endo-1,3-beta-Xilosidasa
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA