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1.
J Phys Condens Matter ; 29(8): 085502, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28081007

RESUMEN

The valence band (VB) structures of wurtzite AlCrN (Cr concentration: 0-17.1%), which show optical absorption in the ultraviolet-visible-infrared light region, were investigated via photoelectron yield spectroscopy (PYS), x-ray/ultraviolet photoelectron spectroscopy (XPS/UPS), and ab initio density of states (DOS) calculations. An obvious photoelectron emission threshold was observed ~5.3 eV from the vacuum level for AlCrN, whereas no emission was observed for AlN in the PYS spectra. Comparisons of XPS and UPS VB spectra and the calculated DOS imply that Cr 3d states are formed both at the top of the VB and in the AlN gap. These data suggest that Cr doping could be a viable option to produce new materials with relevant energy band structures for solar photoelectric conversion.

2.
Chem Commun (Camb) ; 50(33): 4315-8, 2014 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-24637925

RESUMEN

We have developed a novel synthetic route for the production of fine Mg2Si particles (<1 µm) using NaSi, MgCl2, and Na. Mg2Si was suggested to be formed by a solid-state metathesis reaction, in which MgCl2 reacts with Na to form Mg and NaCl, and then Mg reacts with NaSi.

3.
Cytogenet Genome Res ; 142(3): 167-73, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24480864

RESUMEN

Gene amplification represents one of the molecular mechanisms of oncogene overexpression in many types of tumors. Homogeneously staining regions (HSRs) are cytogenetic hallmarks of gene amplification. Rhabdomyosarcoma is the most common malignant soft-tissue tumor in children. RMS-YM is an embryonal rhabdomyosarcoma cell line that possesses 3 HSRs. This cytogenetic finding suggests the presence of gene amplifications associated with tumor development or progression in RMS-YM. Here, using fluorescence in situ hybridization, we detected high amplification of the MDM2 gene in the HSRs of RMS-YM. We also refined the region of the amplicon and identified that the FRS2 gene and others are amplified in RMS-YM. MDM2 and FRS2 play important roles as a regulator of p53 and a mediator of FGF signaling, respectively, and thus are potential molecular targets for therapy in many different tumors. RMS-YM may be useful for studies of the molecular pathways of tumorigenesis and tumor progression in rhabdomyosarcoma and for in vitro evaluation of newly developed therapeutic agents that target MDM2 or FRS2.


Asunto(s)
Cromosomas Humanos Par 12/genética , Amplificación de Genes/genética , Oncogenes , Proteínas Proto-Oncogénicas c-mdm2/genética , Rabdomiosarcoma Embrionario/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Línea Celular Tumoral , Preescolar , Aberraciones Cromosómicas , Bandeo Cromosómico , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Proteínas de la Membrana/genética , Polimorfismo de Nucleótido Simple , Transducción de Señal/genética
5.
J Chem Phys ; 135(3): 034704, 2011 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-21787020

RESUMEN

The local electronic structures of crystalline and amorphous films of zinc phthalocyanine (ZnPc) and metal-free phthalocyanine (H(2)Pc) have been studied by soft x-ray emission spectroscopy (XES). We found a clear crystalline structure dependence of the elastic-peak shape in the resonant XES spectra. The elastic peaks of both ZnPc and H(2)Pc are found to show an asymmetric shape due to resonant inelastic x-ray scattering (RIXS) at the nitrogen sites for the α-crystalline films, but not for the amorphous films. The observed RIXS feature is ascribed to the charge transfer excitation due to the Raman-active intermolecular interaction, which dominates the excited-electron dynamics in α-crystalline phthalocyanine films.


Asunto(s)
Indoles/química , Membranas Artificiales , Compuestos Organometálicos/química , Cristalización , Isoindoles , Estructura Molecular , Espectrometría por Rayos X , Compuestos de Zinc
6.
Ann Oncol ; 22(7): 1601-1607, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21199885

RESUMEN

BACKGROUND: CD5-positive (CD5+) diffuse large B-cell lymphoma (DLBCL) shows poor prognosis and frequent central nervous system (CNS) relapses under anthracycline-containing chemotherapy. The aim of this study was to determine the prognosis and CNS relapse incidence of CD5+ DLBCL in the rituximab era. PATIENTS AND METHODS: We analyzed 337 patients with CD5+ DLBCL who received chemotherapy with (R-chemotherapy group; n = 184) or without (chemotherapy group; n = 153) rituximab. RESULTS: No significant difference was found in clinical background comparisons between the two groups. In the R-chemotherapy group, 60% of the patients were older than 65 years at diagnosis. Both the complete response rate and overall survival (OS) were significantly better in the R-chemotherapy group (P = 0.0003 and P = 0.002, respectively). Multivariate analysis confirmed that chemotherapy without rituximab was associated with unfavorable OS. However, the probability of CNS relapse did not differ between the two groups (P = 0.89). The CNS relapse was strongly associated with short OS (P < 0.0001). In the R-chemotherapy group, 83% of patients who experienced CNS relapse had parenchymal disease. CONCLUSIONS: Our results indicate that rituximab improves the OS of patients with CD5+ DLBCL but does not decrease the CNS relapse rate. More effective treatments with CNS prophylaxis are needed for CD5+ DLBCL patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Antígenos CD5/metabolismo , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/secundario , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Linfoma de Células B Grandes Difuso/metabolismo , Linfoma de Células B Grandes Difuso/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Prednisona/administración & dosificación , Inducción de Remisión , Estudios Retrospectivos , Rituximab , Tasa de Supervivencia , Resultado del Tratamiento , Vincristina/administración & dosificación , Adulto Joven
7.
Phys Rev Lett ; 105(4): 046103, 2010 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-20867867

RESUMEN

The correlation between the geometric and electronic structures of Zn-phthalocyanine (ZnPc) and F16ZnPc on Cu(111) were studied by x-ray standing wave and angle-resolved photoemission spectroscopy. We found evidence for a distortion of the planar molecules upon adsorption, with the central Zn atom in the molecule protruding towards the substrate. This modifies the energy levels of both the molecule and the substrate, which appear as interface states. The site-specific geometric and electronic relaxations are an important effect for organic-metal interface energetics.

8.
Amino Acids ; 38(1): 57-64, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19023642

RESUMEN

The central effects of L-proline, D-proline and trans-4-hydroxy-L-proline were investigated by using the acute stressful model with neonatal chicks in Experiment 1. Sedative and hypnotic effects were induced by all compounds, while plasma corticosterone release under isolation stress was only attenuated by L-proline. To clarify the mechanism by which L-proline and D-proline induce sedative and hypnotic effects, the contribution of the strychnine-sensitive glycine receptor (glycine receptor) and N-methyl-D-aspartate glutamate receptor (NMDA receptor) were further investigated. In Experiments 2-3, the glycine receptor antagonist strychnine was co-injected intracerebroventricular (i.c.v.) with L-proline or D-proline. The suppression of isolation-induced stress behavior by D-proline was attenuated by strychnine. However, the suppression of stress behavior by L-proline was not attenuated. In Experiment 4, the NMDA receptor antagonist (+)-MK-801 was co-injected i.c.v. with L-proline. The suppression of stress behavior by L-proline was attenuated by (+)-MK-801. These results indicate that L-proline and D-proline differentially induce sedative and hypnotic effects through NMDA and glycine receptors, respectively.


Asunto(s)
Conducta Animal/efectos de los fármacos , Pollos/fisiología , Hipnóticos y Sedantes/administración & dosificación , Prolina/administración & dosificación , Estrés Fisiológico/efectos de los fármacos , Animales , Hipnóticos y Sedantes/química , Hipnóticos y Sedantes/metabolismo , Inyecciones , Inyecciones Intraventriculares , Masculino , Prolina/química , Prolina/metabolismo , Receptores de Glicina/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Vocalización Animal/efectos de los fármacos
9.
Cytogenet Genome Res ; 125(3): 201-12, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19738380

RESUMEN

Spectral karyotyping (SKY) was used to assess the chromosomal constitution of embryos generated by nuclear transfer (NT) of neuronal nuclei (N-NT) or cumulus cell nuclei (C-NT) into oocytes and of their embryonic stem cell derivatives (ntES cells). We detected chromosomal changes during the first mitotic cleavage and in the condensed chromatids of NT embryos. We also found clonal translocations in the ntES cells that were derived from NT embryos cloned from neuronal nuclei. The differentiation potentials of the ntES cells showing chromosomal rearrangements were partly restricted. Our findings indicate that balanced or unbalanced chromosomal translocations can occur in early NT embryogenesis, suggesting that a DNA repair system is activated during both NT embryogenesis and ntES cell establishment. We observed a higher incidence of chromosomal changes in N-NT than in C-NT embryos, which may reflect a higher frequency of double-stranded (ds) DNA breaks in the neuronal genome.


Asunto(s)
Cromosomas , Células Madre Embrionarias/citología , Mitosis , Neuronas/citología , Oocitos/citología , Animales , Diferenciación Celular , Células Cultivadas , Células Madre Embrionarias/metabolismo , Femenino , Genoma , Cariotipificación , Masculino , Ratones , Neuronas/metabolismo , Técnicas de Transferencia Nuclear
10.
Mini Rev Med Chem ; 9(3): 300-5, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19275722

RESUMEN

The naturally-occurring dipeptide carnosine (beta-alanyl-L-histidine) and the tripeptide glutathione (L-gammaglutamyl-L-cysteinylglycine) are found extensively in animal tissues such as brain and skeletal muscle. Central functions for excitation and sedation of them and their derivatives were screened.


Asunto(s)
Estimulantes del Sistema Nervioso Central/farmacología , Dipéptidos/farmacología , Evaluación Preclínica de Medicamentos , Hipnóticos y Sedantes/farmacología , Animales , Carnosina/análogos & derivados , Carnosina/farmacología , Carnosina/fisiología , Dipéptidos/fisiología , Glutatión/análogos & derivados , Glutatión/farmacología , Glutatión/fisiología , Modelos Biológicos , Estructura Molecular
11.
Amino Acids ; 37(4): 733-9, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19018608

RESUMEN

Glutamate, an excitatory amino acid, acts at several glutamate receptor subtypes. Recently, we reported that central administration of glutathione induced hypnosis under stressful conditions in neonatal chicks. Glutathione appears to bind to the N-methyl-D-aspartate (NMDA) receptor. To clarify the involvement of each glutamate receptor subtype during stressful conditions, intracerebroventricular (i.c.v.) injection of several glutamate receptor agonists was given to chicks under social separation stress. Glutamate dose-dependently induced a hypnotic effect. NMDA, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) and kainate are characterized as ionotropic glutamate receptors (iGluRs). Although NMDA also induced a sedative effect, [corrected] the potency of NMDA for sleep-like behavior [corrected] was less than that of glutamate. AMPA tended to decrease distress vocalizations induced by acute stress and brought about a sedative effect. Kainate and (S)-3, 5-dehydroxyphenylglycine, which is a metabotropic glutamate receptor agonist, had no influence on chick behavior. Thus, it is suggested that the iGluRs, NMDA and AMPA, are important in inducing hypnosis and sedation under acute stress in chicks.


Asunto(s)
Pollos/fisiología , Ácido Glutámico/metabolismo , Pérdida de Tono Postural , N-Metilaspartato/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Estrés Psicológico/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/metabolismo , Animales , Pollos/metabolismo , Agonistas de Aminoácidos Excitadores/administración & dosificación , Ácido Glutámico/administración & dosificación , Ácido Kaínico/administración & dosificación , Ácido Kaínico/metabolismo , Masculino , Metoxihidroxifenilglicol/administración & dosificación , Metoxihidroxifenilglicol/análogos & derivados , Metoxihidroxifenilglicol/metabolismo , N-Metilaspartato/administración & dosificación , Receptores de N-Metil-D-Aspartato/agonistas , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/administración & dosificación
12.
J Fish Biol ; 75(3): 563-74, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20738557

RESUMEN

Although previous studies have claimed that Pungtungia herzi (Cyprinidae) is an obligate brood parasite, in this study a significant proportion of P. herzi egg masses was found in crevices formed by stones and rocks, which was not guarded by hosts. Egg masses were also found in almost all nests of a goby Odontobutis obscura, suggesting that P. herzi has two alternative reproductive tactics: brood parasitic spawning and non-parasitic crevice spawning, the latter of which may occur when a shortage of reproductive resources (i.e. host nests) exists. The hatching rates of parasitic egg masses were significantly higher than those of non-parasitic egg masses, and the hatching rate of P. herzi eggs exhibited a strong positive correlation with continuous egg guarding by a reproductive O. obscura male. These results indicate that brood parasitism effectively improves reproductive success in P. herzi. The alternative reproductive tactic of this species suggests that brood parasitism has evolved directly from crevice spawning via the sharing of spawning habitat with host species.


Asunto(s)
Cyprinidae/fisiología , Comportamiento de Nidificación/fisiología , Reproducción/fisiología , Animales , Huevos , Femenino , Interacciones Huésped-Parásitos , Masculino
13.
Amino Acids ; 35(1): 107-13, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18219550

RESUMEN

Recently, we observed that central administration of L-arginine attenuated stress responses in neonatal chicks, but the contribution of nitric oxide (NO) to this response was minimal. The sedative and hypnotic effects of L-arginine may be due to L-arginine itself and/or its metabolites, excluding NO. To clarify the mechanism, the effect of intracerebroventricular (i.c.v.) injection of L-arginine metabolites on behavior under social separation stress was investigated. The i.c.v. injection of agmatine, a guanidino metabolite of L-arginine, had no effect during a 10 min behavioral test. In contrast, the i.c.v. injection of L-ornithine clearly attenuated the stress response in a dose-dependent manner, and induced sleep-like behavior. The L-ornithine concentration in the telencephalon and diencephalon increased following the i.c.v. injection of L-arginine. In addition, several free amino acids including L-alanine, glycine, L-proline and L-glutamic acid concentrations increased in the telencephalon. In conclusion, it appears that L-ornithine, produced by arginase from L-arginine in the brain, plays an important role in the sedative and hypnotic effects of L-arginine observed during a stress response. In addition, several other amino acids having a sedative effect might partly participate in the sedative and hypnotic effects of L-arginine.


Asunto(s)
Arginina/farmacología , Conducta Animal/efectos de los fármacos , Química Encefálica/efectos de los fármacos , Hipnóticos y Sedantes/farmacología , Ornitina/metabolismo , Estrés Fisiológico/metabolismo , Aminoácidos , Animales , Animales Recién Nacidos , Arginina/metabolismo , Pollos , Diencéfalo/metabolismo , Relación Dosis-Respuesta a Droga , Hipnóticos y Sedantes/metabolismo , Telencéfalo/metabolismo
14.
Amino Acids ; 35(1): 139-46, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18163184

RESUMEN

L-arginine participates in many important and diverse biochemical reactions associated with the normal physiology of the organism. In the present study, we investigated the effect of central administration of L-arginine on the stress response and its mechanism in neonatal chicks. Intracerebroventricular (i.c.v.) injection of L-arginine clearly attenuated the stress response in a dose-dependent manner, and induced sleep-like behavior during 10 min. To clarify the mechanism by which L-arginine induces sedative and hypnotic effects in chicks, we investigated the effects of nitric oxide (NO) synthase (NOS) inhibitors on L-arginine-induced sedative and hypnotic effects, and as well as the effects of a NO donor. L-Arginine-induced (1.9 micromol) sedative and hypnotic effects were attenuated by i.c.v. co-injection with a non-selective NOS inhibitor N(G)-nitro-L-arginine methyl ester HCl (400 nmol). In addition, the effects of L-arginine were slightly attenuated by the inactive isomer of the NOS inhibitor N(G)-nitro-D-arginine methyl ester HCl (400 nmol). The i.c.v. injection of 3-morpholinosylnomine hydrochloride, a spontaneous NO donor, had little effect on postures. The i.c.v. injection of L-arginine had no effect on NOx concentration at various brain sites. These results suggested that the contribution of NO generation via NOS may be low in the sedative and hypnotic actions of L-arginine. Therefore, L-arginine and/or its metabolites, excluding NO, may be necessary for these actions.


Asunto(s)
Arginina/farmacología , Conducta Animal/efectos de los fármacos , Química Encefálica/efectos de los fármacos , Hipnóticos y Sedantes/farmacología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Estrés Fisiológico/enzimología , Enfermedad Aguda , Animales , Animales Recién Nacidos , Pollos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo I/antagonistas & inhibidores
15.
Amino Acids ; 34(1): 55-60, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17906978

RESUMEN

Intracerebroventricular (i.c.v.) injection of L-serine was shown to have sedative and hypnotic effects on neonatal chicks under acute stressful conditions. To clarify the central mechanism of these effects of L-serine, two experiments were done. First, we focused on the glycogenic pathway in which L-serine is converted into pyruvate and finally glucose. I.c.v. administration of pyruvate (0.84 micromol) did not induce any behavioral and endocrinological changes, while L-serine and glucose triggered sedative and hypnotic effects. Secondly, the relationship between the sedation by L-serine and the metabolism into other amino acids which have sedative effects was investigated in the telencephalon and diencephalon. In both brain areas, a dose-dependent increase was seen in L-serine, although other amino acids were not changed. In the present study, it was concluded that the sedative action of L-serine was not due to the action of its metabolite pyruvate, or to the action of other amino acids.


Asunto(s)
Aminoácidos/administración & dosificación , Hipnóticos y Sedantes/administración & dosificación , Ácido Pirúvico/administración & dosificación , Aminoácidos/química , Aminoácidos/metabolismo , Aminoácidos/farmacología , Animales , Animales Recién Nacidos , Pollos , Glucosa/administración & dosificación , Glucosa/farmacología , Hipnóticos y Sedantes/química , Hipnóticos y Sedantes/metabolismo , Hipnóticos y Sedantes/farmacología , Inyecciones , Masculino , Estructura Molecular , Ácido Pirúvico/química , Ácido Pirúvico/metabolismo , Ácido Pirúvico/farmacología , Factores de Tiempo
16.
AJNR Am J Neuroradiol ; 28(7): 1375-7, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17698545

RESUMEN

An organized hematoma is a chronic state of fibrotic tissue surrounding a hemorrhage. A mass lesion resulting from hematoma in the maxillary sinus was first reported in 1917, and the term, "blood boil," was clinically coined from such features as encapsulated blood and locally aggressive behavior. Subsequently, others have reported lesions with a similar appearance and clinical course, and now, in Japan, blood boil is used as a clinical term for such lesions. Factors that may predispose a patient to hematoma formation vary, and the pathogenesis of the mass is still uncertain. The lesions are mainly composed of an organized hematoma, regardless of their origin. We present 2 cases of organized maxillary sinus hematomas that have unusual radiologic findings and correlate these findings with the histopathologic findings.


Asunto(s)
Hematoma/diagnóstico , Imagen por Resonancia Magnética/métodos , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/patología , Enfermedades de los Senos Paranasales/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Humanos , Masculino
17.
Mol Genet Genomics ; 269(1): 90-100, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12715157

RESUMEN

This study identifies and characterizes a basic non-S RNase in the styles with stigmas of sweet cherry (Prunus avium L.), a member of the Rosaceae subfamily Amygdaloideae, which has an RNase-based gametophytic self-incompatibility system. Internal sequences of putative non-S RNases (RNase PA1 and PA2) were determined, and a cDNA for PA1 was obtained. The deduced amino acid sequence of PA1 contained two conserved sequence motifs essential for T2/ S-type RNase activity. PA1 shows 20-30% sequence identity to S-RNases of Rosaceae, Solanaceae and Scrophulariaceae, and non-S RNases of higher plants. Transcription of the PA1 gene was specific to the styles with stigmas, and the gene was not expressed in other tissues. Although PA1 resembles RNase X2, a non-S RNase from Petunia inflata, the placement of PA1 and RNase X2 in the phylogenetic tree was quite different. Placement of PA1 was also distinct from that of rosaceous S-RNases, while RNase X2 was incorporated in the clade of S-RNases from the Solanaceae. The sole intron in the PA1 gene is located at a position equivalent to that of the second intron of amygdaloid S-RNase genes, and that of the only intron in most other S-RNase genes. Genomic Southern analysis revealed the presence of sequences homologous to PA1 in all of the other four Prunus species tested, suggesting that PA1 has an important physiological function. The significance of the discovery of PA1 is discussed in terms of the origin and evolution of S-RNases and self-incompatibility in Rosaceae.


Asunto(s)
ADN de Plantas/genética , Prunus/genética , Ribonucleasas/química , Ribonucleasas/genética , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , ADN Complementario/genética , Evolución Molecular , Genes de Plantas , Datos de Secuencia Molecular , Filogenia , Prunus/enzimología , Ribonucleasas/aislamiento & purificación , Ribonucleasas/metabolismo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Especificidad de la Especie
18.
Theor Appl Genet ; 105(2-3): 222-228, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12582523

RESUMEN

Self-compatible cultivars of Japanese apricot ( Prunus mume Shieb. et Zucc.), a tree species that normally shows S-RNase-based self-incompatiblity, have a horticultural advantage over self-incompatible cultivars. Inheritance of self-compatibility and a common S(f)-RNase allele that is observed in self-compatible cultivars was investigated using progenies from controlled crosses. Total DNAs were isolated from the parents and progenies of seven crosses that included at least one self-compatible cultivar as a parent. These DNAs were PCR-amplified with the Pru-C2 and PCE-R primer pair to determine S-haplotypes of the parents and progenies. A novel S-haplotype, S(8), was found. In all crosses examined, the S(f)-RNase gene was inherited from either the seed or pollen parent as a pistil S-allele in a non-functional S-haplotype. Self-compatibility of about 20 trees each from reciprocal crosses of 'Benisashi ( S(7) S(f))' and 'Shinpeidayu ( S(3) S(f))', and 26 selections from 16 different crosses was tested by pollination and pollen-tube growth studies. Cosegregation of the S(f)-RNase allele and self-compatibility was confirmed with all but selection 1K0-26 ( S(3) S(7)). Selection 1K0-26 ( S(3) S(7)) that originated from 'Benisashi ( S(7) S(f))' x 'Koshinoume ( S(3) S(f))' appeared to be self-compatible even without the S(f)-RNase allele. The possible role of pollen- S, a presumably existing pollen component of gametophytic self-incompatibility, is discussed.

19.
Plant Cell Physiol ; 42(11): 1290-3, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11726715

RESUMEN

The expression of a papain-type proteinase, designated SH-EP, in cotyledons of Vigna mungo seedlings has been shown to require some factors in the embryonic axes. Gibberellin A1 (GA(1)) and GA(20) were identified by GC-MS in embryonic axes of V. mungo seedlings. The level of accumulation of SH-EP in cotyledons of V. mungo seedlings was greatly reduced by treatment of the seeds with uniconazole-P, an inhibitor for GA biosynthesis. The reduced level of accumulation of SH-EP in cotyledons by uniconazole-P was recovered by exogenous application of GA(1) and GA(20) to the seedlings.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Fabaceae/metabolismo , Giberelinas/metabolismo , Cotiledón/genética , Cotiledón/metabolismo , Cisteína Endopeptidasas/genética , Fabaceae/enzimología , Fabaceae/genética , Cromatografía de Gases y Espectrometría de Masas , Germinación/fisiología , Giberelinas/farmacología , Triazoles/farmacología
20.
Proc Natl Acad Sci U S A ; 98(26): 15137-42, 2001 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-11752460

RESUMEN

Differentiation of naive CD4(+) T cells into IFN-gamma-producing T helper 1 (T(H)1) cells is pivotal for protective immune responses against intracellular pathogens. T-bet, a recently discovered member of the T-box transcription factor family, has been reported to play a critical role in this process, promoting IFN-gamma production. Although terminal T(H)1 differentiation occurs over days, we now show that challenge of mice with a prototypical T(H)1-inducing stimulus, Toxoplasma gondii soluble extract, rapidly induced IFN-gamma and T-bet; T-bet induction was substantially lower in IFN-gamma-deficient mice. Naive T cells expressed little T-bet, but this transcription factor was induced markedly by the combination of IFN-gamma and cognate antigen. Human myeloid antigen-presenting cells showed T-bet induction after IFN-gamma stimulation alone, and this induction was antagonized by IL-4 and granulocyte/macrophage colony-stimulating factor. Although T-bet was induced rapidly and directly by IFN-gamma, it was not induced by IFN-alpha, lipopolysaccharide, or IL-1, indicating that this action of IFN-gamma was specific. Moreover, T-bet induction was dependent on Stat1 but not Stat4. These data argue for a model in which IFN-gamma gene regulation involves an autocrine loop, whereby the cytokine regulates a transcription factor that promotes its own production. These findings substantially alter the current view of T-bet in IFN-gamma regulation and promotion of cell-mediated immune responses.


Asunto(s)
Linfocitos T CD4-Positivos/metabolismo , Células Dendríticas/metabolismo , Interferón gamma/fisiología , Macrófagos/metabolismo , Factores de Transcripción/biosíntesis , Animales , Anticuerpos Monoclonales/inmunología , Secuencia de Bases , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular/fisiología , Células Cultivadas , Cartilla de ADN , Células Dendríticas/inmunología , Femenino , Humanos , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Proteínas de Dominio T Box , Factores de Transcripción/fisiología , Regulación hacia Arriba
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