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1.
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
2.
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
3.
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
4.
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.

5.
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
6.
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
7.
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
8.
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
9.
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
11.
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
12.
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
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.
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
15.
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.

16.
Plant Physiol ; 109(4): 1239-1245, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12228665

RESUMEN

ent-Kaurene synthase B (KSB) was purified 291-fold from a crude enzyme preparation from endosperm of pumpkin (Cucurbita maxima L.). Separation of ent-kaurene synthase A and KSB was achieved by hydrophobic interaction chromatography. The fractions containing KSB activity were further purified by diethylaminoethyl, phenyl, and hydroxyapatite column chromatography. Using sodium dodecyl phosphate-polyacrylamide gel electrophoresis, the purest enzyme preparation showed a major band at an apparent molecular mass of 81 kD. The amount of protein in this band was correlated with KSB activity after diethylaminoethyl and hydroxyapatite chromatography. The N terminus of the 81-kD protein was blocked. Therefore, the protein was partially digested with protease and the amino acid sequences of the resulting major peptide fragments were analyzed. A polyclonal antibody was raised against a synthetic peptide based on the longest peptide fragment combined with a keyhole limpet hemocyanin. The antibody recognized only the 81-kD denatured protein and not the native KSB. The properties of KSB were examined using the phenyl-purified enzyme preparation. The Km value for copalyl pyrophosphate was 0.35 [mu]M, and the optimal pH was 6.8 to 7.5. The KSB activity required divalent cations such as Mg2+, Mn2+, and Co2+, whereas Cu2+, Ca2+, and Ba2+ inhibited the activity.

17.
Plant Physiol ; 111(3): 741-745, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12226326

RESUMEN

Antheridiogens in two species of Schizaeaceous ferns, Lygodium circinnatum and Lygodium flexuosum, were analyzed by gas chromatography-mass spectrometry. In L. circinnatum, gibberellin A73 (GA73) methyl ester (GA73-Me), which had originally been identified in L. japonicum, was identified as a principal antheridiogen, and the methyl esters of five known GAs (GA9, GA20, GA70, GA88, and 3-epi-GA88) were also identified as minor antheridiogens. In addition, four compounds corresponding to isomers of monohydroxy-GA73-Me were detected. One of these was shown to be 12[beta]-hydroxy-GA73-Me, the parent acid of which has been allocated the GA assignment GA96. The other three compounds, tentatively named X1, X2, and X3, have not been fully characterized. In L. flexuosum, GA73-Me was also identified as a major antheridiogen, with X2 being detected as a minor one. The total antheridium-formation activity in the culture medium of 7-week-old prothallia of L. circinnatum and L. flexuosum was more than 1000 times higher than that of L. japonicum. On the other hand, the response of gametophytes of the former two Lygodium ferns to GA73-Me was more than 100 times lower than that of L. japonicum.

18.
Plant Physiol ; 113(3): 773-778, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12223642

RESUMEN

Biosynthesis of GA73 methyl ester (GA73-Me), the principal antheridiogen in Lygodium ferns, was investigated. From the methanol extract of prothallia of Lygodium circinnatum, GA25, GA73, GA73-Me, GA88-Me, and a few unknown GA73 derivatives were detected by GC-MS. Because the presence of GA25 suggests that GA24, a direct precursor of GA25, could also be present in L. circinnatum prothallia, we used feeding experiments to investigate the possibility that GA24 is a precursor of GA73-Me. In L. circinnatum prothallia, [2H2]GA24 was converted into [2H2]GA73-Me and a trace amount of [2H2]GA9-Me, whereas [2H3]GA9 was converted into [2H3]GA9-Me and [2H3]monohydroxy-GA9-Me. Because GA73-Me, GA9-Me, and their monohydroxy derivatives had been identified by GC-MS from the culture medium of L. circinnatum prothallia, our results suggest that GA73-Me is biosynthesized from GA24 via GA73, and that neither GA9 nor GA9-Me is a precursor of GA73-Me. Though the possibility had been suggested that GA73-Me is biosynthesized from 9,15-cyclo-GA9 (GA103), [2H2]GA103 was not converted into [2H2]GA73-Me.

19.
Plant Physiol ; 110(2): 387-392, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12226190

RESUMEN

It has been suggested that jasmonic acid (JA) could be an integral part of a general signal transduction system regulating inducible defense genes in plants. It was reported that treatment with an elicitor (N-acetylchitoheptaose) induced production of phytoalexin in suspension-cultured rice (Oryza sativa L.) cells. In this study, the role of JA in the induction of phytoalexin production by N-acetylchitoheptaose was investigated. Exogenously applied ([plus or minus])-JA (10-4 M) clearly induced the production of momilactone A, a major phytoalexin, in suspension-cultured rice cells. On the other hand, in rice cells treated with N-acetylchitoheptaose, endogenous JA was rapidly and transiently accumulated prior to accumulation of momilactone A. Treatment with ibuprofen, an inhibitor of JA biosynthesis, reduced production of momilactone A in the cells treated with N-acetylchitoheptaose, but the addition of ([plus or minus])-JA increased production of momilactone A to levels higher than those in the elicited rice cells. These results strongly suggest that JA functions as a signal transducer in the induction of biosynthesis of momilactone A by N-acetylchitoheptaose in suspension-cultured rice cells.

20.
Clin Cancer Res ; 5(4): 933-6, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10213231

RESUMEN

Loss of expression of HLA class I antigens has been demonstrated in a wide variety of tumors and is considered to be one of the mechanisms whereby tumors escape T-cell surveillance. Genomic DNA of MHC class I/II molecules in seven lung cancer cell lines was investigated and compared with that in peripheral blood mononuclear cells. In three cell lines, OU-LC-A1, OU-LC-A2, and OU-LC-AS1, a loss of HLA haplotype was observed. Aberrations of HLA class I/II in tumor cell lines should be considered when MHC-restricted phenomena in vitro models are assessed and clinical use of tumor vaccination in vivo is considered.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/inmunología , Antígenos HLA/genética , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase I/genética , Neoplasias Pulmonares/inmunología , Carcinoma de Pulmón de Células no Pequeñas/genética , ADN/genética , Haplotipos , Humanos , Vigilancia Inmunológica , Neoplasias Pulmonares/genética , Masculino , Fenotipo , Reacción en Cadena de la Polimerasa , Serotipificación , Células Tumorales Cultivadas
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