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1.
Eye (Lond) ; 29(12): 1555-60, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26293140

RESUMEN

UNLABELLED: Purpose: To evaluate and compare surgical outcomes with respect to refractive errors in strabismus surgery for the treatment of intermittent exotropia (IXT). METHODS: The medical records of patients with IXT who were treated by one surgeon from January 2005 and June 2011 were reviewed. Three hundred and thirty-three IXT patients were included and divided into three groups according to preoperative refractive error: IXT with hyperopia (group I), IXT with emmetropia (group II), and IXT with myopia (group III). The surgical outcomes with respect to sensory and motor criteria were compared among the three groups. RESULTS: The surgical success rates according to motor criteria and sensory and motor criteria combined were higher in groups I (29 patients) and III (124 patients) than in group II (180 patients) at postoperative 3 and 6 months and at the last follow-up. Stereopsis was significantly better in groups II and III than in group I preoperatively (P=0.002 by one-way analysis of variance test); however, the difference was not significant postoperatively. Twenty patients in group I (69.0%) were prescribed undercorrected hyperopic spectacles postoperatively, while only 22 patients in group III (17.7%) were prescribed spectacles with more myopic power than their refractive errors. CONCLUSION: In the surgical treatment of IXT, hyperopia was not an indicator of poor prognosis. Taking into consideration the age effect, follow-up period after IXT surgery, and stereopsis improvement, hyperopic refractive error is rather a good prognostic factor.


Asunto(s)
Exotropía/cirugía , Hiperopía/diagnóstico , Hiperopía/etiología , Músculos Oculomotores/cirugía , Procedimientos Quirúrgicos Oftalmológicos/efectos adversos , Niño , Preescolar , Percepción de Profundidad/fisiología , Anteojos , Femenino , Humanos , Hiperopía/terapia , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
2.
Br J Dermatol ; 154(5): 829-38, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16634882

RESUMEN

BACKGROUND: Radiation induces many cellular events leading to radiodermatitis. OBJECTIVES: The aim of this study was to establish a radiodermatitis model using experimental animals, and to examine the expression profile of radiation-induced genes. METHODS: Hairless mice were irradiated on the dorsal skin; then total RNAs were isolated and microarray hybridizations were performed. RESULTS: Irradiation with a total of 40 Gy (10 Gy day-1 for four consecutive days) provokes radiodermatitis in the hairless mouse. After microarray analysis, 130 genes that showed upregulation by radiation were selected and organized into four different clusters, depending on the time-kinetic pattern. Classification of these genes into several functional categories revealed that various biological processes were globally affected by radiation. These include transcription regulation, signal transduction, cell communication, cell death regulation and metabolism. CONCLUSIONS: These results demonstrate the complexity of the transcriptional profile of the radiation response, providing important clues on which to base further investigations of the molecular events underlying radiodermatitis.


Asunto(s)
Modelos Animales de Enfermedad , Radiodermatitis/genética , Animales , Relación Dosis-Respuesta en la Radiación , Perfilación de la Expresión Génica , Masculino , Ratones , Ratones Pelados , Análisis por Micromatrices , Familia de Multigenes , Reacción en Cadena de la Polimerasa/métodos , Radiodermatitis/etiología , Regulación hacia Arriba/efectos de la radiación , Pérdida de Peso/efectos de la radiación
3.
J Thromb Haemost ; 1(2): 363-73, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12871512

RESUMEN

The peptide LSARLAF (LSA) causes alphaIIbbeta3-dependent platelet activation that results in alpha-granule secretion and aggregation. LSARLAF-induced, alphaIIbbeta3-mediated outside-in signaling causing alpha-granule secretion and platelet aggregation was studied using washed mouse platelets. ADP receptor antagonists, enzyme inhibitors, normal platelets and platelets from mice that lack either Galphaq or thromboxane (Tx) A2 receptors were used for this investigation. The results demonstrate that LSA-induced alphaIIbbeta3-mediated signaling producing aggregation of washed platelets is mediated through the release of ADP and thromboxane, which cause alpha-granule release by mediating their effects though Galphaq and/or Gi depending on the level of LSA used to activate the platelets. Specifically, alphaIIbbeta3 elicited aggregation of washed platelets in response to a low level of LSA requires signaling through the ADP receptor P2Y1 and Galphaq, and the ADP receptor P2Y12 and Gi as well as TxA2 receptors. However, this aggregation is independent of Galphaq and TxA2 signaling in response to high LSA concentrations, but is dependent on ADP signaling through its receptor P2Y12, and therefore presumably Gi, regardless of the level of LSA used to activate the platelets. PKC function is required for ADP secretion and the subsequent signaling through P2Y12 regardless of the level of LSA used to activate the platelets. The end point of the LSA-induced alphaIIbbeta3-mediated signaling characterized in this study is alpha-granule secretion, which provides the fibrinogen required for aggregation of washed platelets.


Asunto(s)
Plaquetas/efectos de los fármacos , Plaquetas/fisiología , Oligopéptidos/farmacología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/fisiología , Adenosina Difosfato/sangre , Animales , Degranulación de la Célula/efectos de los fármacos , Degranulación de la Célula/fisiología , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gq-G11 , Proteínas de Unión al GTP Heterotriméricas/sangre , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfatidilinositol 3-Quinasas/sangre , Agregación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/fisiología , Proteína Quinasa C/sangre , Receptores Purinérgicos P2/sangre , Receptores de Tromboxanos/sangre , Transducción de Señal/efectos de los fármacos
4.
Theor Appl Genet ; 106(1): 92-100, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12582875

RESUMEN

Introduced transgenes, uidA, sgfp (S65T) and/or bar, were localized using fluorescence in situ hybridization (FISH) on metaphase chromosomes of transgenic barley produced by microparticle bombardment of immature embryos. Of the 19 independent transgenic lines (eight diploid and 11 tetraploid), nine had uidA and ten had s gfp (S65T). All lines tested had three or more copies of the transgenes and 18 out of 19 lines had visibly different integration sites. At a gross level, it appeared that no preferential integration sites of foreign DNA among chromosomes were present in the lines tested; however, a distal preference for transgene integration was observed within the chromosome. In diploid T0 plants that gave a 3:1 segregation ratio of transgene expression in the T1, only single integration sites were detected on one of the homologous chromosomes. Homozygous diploid plants had doublet signals on a pair of homologous chromosomes. All tetraploid T0 plants that gave a 3:1 segregation ratio in the T1 generation had only a single integration site on one of the homologous chromosomes. In contrast, the single tetraploid T0 plant with a 35:1 segregation ratio in the T1 generation had doublet signals on a pair of homologous chromosomes. In the one tetraploid T0 line, which had a homozygote-like segregation ratio (45:0), there were doublet signals at two loci on separate chromosomes. We conclude that the application of FISH for analysis of transgenic plants is useful for the gross localization of transgene(s) and for early screening of homozygous plants.


Asunto(s)
Mapeo Cromosómico , Hordeum/genética , Hibridación Fluorescente in Situ , Transgenes , Acetiltransferasas/genética , Dosificación de Gen , Expresión Génica , Homocigoto , Fenotipo , Plantas Modificadas Genéticamente , Poliploidía
5.
Mol Cells ; 12(2): 204-8, 2001 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-11710522

RESUMEN

Cold acclimation enhances the transcription of several cold regulated (COR) genes. However, little is known about whether the elevation of the transcriptional level of the COR genes is due to transcriptional activation, or mRNA stability by a low temperature. Recently, we cloned a novel cold-inducible zinc finger protein gene from soybean, SCOF-1, which may function as a positive regulator of the COR gene expression . Here we report that the elevation of the SCOF-1 transcript level by cold stress is associated with both transcriptional activation and post-transcriptional mRNA stability under a low temperature. A nuclear run-on assay reveals that cold acclimation elevates the SCOF-1 transcript about three-fold compared to that of non-acclimated soybean nuclei. Furthermore, SCOF-1 transcripts increased substantially by a low temperature in transgenic tobacco plants that constitutively expressed SCOF-1 under the control of a constitutive cauliflower mosaic virus (CaMV) 35S promoter. When a transcription inhibitor, cordycepin, was treated with the deacclimating soybean cell, the decay level of the SCOF-1 transcripts was delayed significantly. This suggests that it may affect de novo protein synthesis, which degrades the SCOF-1 mRNA at room temperature. In addition, a secondary structure may be involved in the mRNA stability of SCOF-1 under a low temperature.


Asunto(s)
Proteínas de Choque Térmico/genética , Proteínas de Plantas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Factores de Transcripción/genética , Aclimatación/genética , Secuencia de Bases , Frío , ADN Complementario/genética , ADN de Plantas/genética , Conformación de Ácido Nucleico , Plantas Modificadas Genéticamente , Estabilidad del ARN , ARN Mensajero/química , ARN de Planta/química , Glycine max/genética , Glycine max/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Activación Transcripcional , Dedos de Zinc/genética
6.
Anal Biochem ; 293(1): 1-7, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11373071

RESUMEN

Antisense oligonucleotides have shown great promise over the past several years as viable drugs to combat various forms of cancer and viral diseases. However, quantitative detection to monitor cellular association is difficult using conventional methods such as radiolabeling of the oligonucleotide or fluorescence confocal microscopy. In this paper quantitation of intracellular concentration of the morpholino oligonucleotide is investigated using capillary electrophoresis coupled with laser-induced fluorescence detection (CE-LIF). HeLa cells, which produce luciferase as the antisense oligomer enters the cell, were scrape-loaded with varying concentrations of the morpholino antisense. The intracellular antisense concentration measured by CE-LIF was found to correlate with those obtained with the cellular functional assay based on upregulation of luciferase. Intracellular concentrations of the antisense were found to be in the range of 6 to 29 nmol/g total cell protein, depending on the amounts that were scrape-loaded. To our best knowledge, this is the first reported quantitative correlation between delivered antisense concentration in a cell extract and the subsequent antisense upregulation of gene expression.


Asunto(s)
Electroforesis Capilar/métodos , Células HeLa/metabolismo , Luciferasas/genética , Oligonucleótidos Antisentido/análisis , Preparaciones Farmacéuticas/análisis , Membrana Celular/fisiología , Sistemas de Liberación de Medicamentos , Fluoresceínas , Fluorescencia , Colorantes Fluorescentes , Expresión Génica , Humanos , Rayos Láser , Fluidez de la Membrana , Microscopía Confocal , Regulación hacia Arriba
7.
Am Surg ; 67(3): 215-9; discussion 219-20, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11270877

RESUMEN

Serum amylase and lipase elevation has been observed in trauma patients and patients with traumatic intracranial bleeding. However, the causes of this elevation have not been clearly elucidated. A further question remains as to whether other intracranial events are associated with such enzyme elevation as well. We retrospectively reviewed 75 patients consecutively admitted to Cook County Hospital Neurosurgical Intensive Care Unit over a 3-month period for trauma, infection, tumor, or other space-occupying lesions with an unstable condition or neurological deficit. Eleven patients (15%) had elevated amylase and lipase levels. The patients were divided into two groups: Group I (n = 64) had normal and Group II (n = 11) had raised amylase and lipase levels [amylase 402 +/- 444 U/L with normal < or = 125 U/L and lipase 474 +/- 313 U/L with normal < or = 55 U/L]. All Group II patients suffered an intracranial event. Twenty-four Group I (38%) and 10 Group II (91%) patients required craniotomy (P < 0.01). No patients had clinical or radiographic evidence of pancreatitis. In summary, intracranial events are associated with serum amylase and lipase elevation probably through centrally activated pathways. Because of the lack of diagnostic value, routine pancreatic enzyme monitoring should not be performed in this patient population.


Asunto(s)
Amilasas/sangre , Encefalopatías/enzimología , Neoplasias Encefálicas/enzimología , Traumatismos Craneocerebrales/enzimología , Infecciones/enzimología , Aneurisma Intracraneal/enzimología , Hemorragias Intracraneales/enzimología , Lipasa/sangre , Enfermedades de la Columna Vertebral/enzimología , Traumatismos Vertebrales/enzimología , Anciano , Encefalopatías/sangre , Encefalopatías/mortalidad , Encefalopatías/terapia , Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/terapia , Traumatismos Craneocerebrales/sangre , Traumatismos Craneocerebrales/mortalidad , Traumatismos Craneocerebrales/terapia , Craneotomía , Femenino , Mortalidad Hospitalaria , Humanos , Infecciones/sangre , Infecciones/mortalidad , Infecciones/terapia , Aneurisma Intracraneal/sangre , Aneurisma Intracraneal/mortalidad , Aneurisma Intracraneal/terapia , Hemorragias Intracraneales/sangre , Hemorragias Intracraneales/mortalidad , Hemorragias Intracraneales/terapia , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/normas , Estudios Retrospectivos , Enfermedades de la Columna Vertebral/sangre , Enfermedades de la Columna Vertebral/mortalidad , Enfermedades de la Columna Vertebral/terapia , Traumatismos Vertebrales/sangre , Traumatismos Vertebrales/mortalidad , Traumatismos Vertebrales/terapia , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler Transcraneal
8.
Plant J ; 25(3): 247-59, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11208017

RESUMEN

Cold stress on plants induces changes in the transcription of cold response genes. A cDNA clone encoding C2H2-type zinc finger protein, SCOF-1, was isolated from soybean. The transcription of SCOF-1 is specifically induced by low temperature and abscisic acid (ABA) but not by dehydration or high salinity. Constitutive overexpression of SCOF-1 induced cold-regulated (COR) gene expression and enhanced cold tolerance of non-acclimated transgenic Arabidopsis and tobacco plants. SCOF-1 localized to the nucleus but did not bind directly to either C-repeat/dehydration (CRT/DRE) or ABA responsive element (ABRE), cis-acting DNA regulatory elements present in COR gene promoters. However, SCOF-1 greatly enhanced the DNA binding activity of SGBF-1, a soybean G-box binding bZIP transcription factor, to ABRE in vitro. SCOF-1 also interacted with SGBF-1 in a yeast two-hybrid system. The SGBF-1 transactivated the beta-glucuronidase reporter gene driven by the ABRE element in Arabidopsis leaf protoplasts. Furthermore, the SCOF-1 enhanced ABRE-dependent gene expression mediated by SGBF-1. These results suggest that SCOF-1 may function as a positive regulator of COR gene expression mediated by ABRE via protein-protein interaction, which in turn enhances cold tolerance of plants.


Asunto(s)
Adaptación Fisiológica/genética , Frío , Glycine max/genética , Proteínas de Choque Térmico/fisiología , Proteínas de Plantas , Plantas Modificadas Genéticamente/fisiología , Factores de Transcripción/fisiología , Dedos de Zinc , Ácido Abscísico/farmacología , Secuencia de Aminoácidos , Secuencia de Bases , Núcleo Celular/metabolismo , Cartilla de ADN , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes Reporteros , Glucuronidasa/genética , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/genética , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente/genética , Homología de Secuencia de Aminoácido , Factores de Transcripción/química , Factores de Transcripción/genética , Activación Transcripcional
9.
FEBS Lett ; 486(2): 103-6, 2000 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-11113447

RESUMEN

Possible functions that have been proposed for the plant 1Cys-peroxiredoxin, include activity as a dormancy regulator and as an antioxidant. The transcript level of rice 1Cys-peroxiredoxin (R1C-Prx) rapidly decreased after imbibition of rice seeds, but the protein was detected for 15 days after imbibition. To investigate the function of this protein, we generated transgenic tobacco plants constitutively expressing the R1C-Prx gene. The transgenic R1C-Prx plants showed a germination frequency similar to control plants. However, the transgenic lines exhibited higher resistance against oxidative stress, suggesting that antioxidant activity may be its primary function.


Asunto(s)
Antioxidantes , Oryza/enzimología , Peroxidasas/fisiología , Animales , Expresión Génica , Germinación/fisiología , Oryza/genética , Oryza/fisiología , Estrés Oxidativo , Peroxidasas/genética , Peroxirredoxinas , Plantas Modificadas Genéticamente , Plantas Tóxicas , Conejos , Semillas/fisiología , Nicotiana
10.
Biochem J ; 350 Pt 1: 299-306, 2000 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10926857

RESUMEN

Multiple calmodulin (CaM) isoforms are expressed in plants, but their biochemical characteristics are not well resolved. Here we show the differential regulation exhibited by two soya bean CaM isoforms (SCaM-1 and SCaM-4) for the activation of five CaM-dependent enzymes, and the Ca(2+) dependence of their target enzyme activation. SCaM-1 activated myosin light-chain kinase as effectively as brain CaM (K(act) 1.8 and 1.7 nM respectively), but SCaM-4 produced no activation of this enzyme. Both CaM isoforms supported near maximal activation of CaM-dependent protein kinase II (CaM KII), but SCaM-4 exhibited approx.12-fold higher K(act) than SCaM-1 for CaM KII phosphorylation of caldesmon. The SCaM isoforms showed differential activation of plant and animal Ca(2+)-ATPases. The plant Ca(2+)-ATPase was activated maximally by both isoforms, while the erythrocyte Ca(2+)-ATPase was activated only by SCaM-1. Plant glutamate decarboxylase was activated fully by SCaM-1, but SCaM-4 exhibited an approx. 4-fold increase in K(act) and an approx. 25% reduction in V(max). Importantly, SCaM isoforms showed a distinct Ca(2+) concentration requirement for target enzyme activation. SCaM-4 required 4-fold higher [Ca(2+)] for half-maximal activation of CaM KII, and 1.5-fold higher [Ca(2+)] for activation of cyclic nucleotide phosphodiesterase than SCaM-1. Thus these plant CaM isoforms provide a mechanism by which a different subset of target enzymes could be activated or inhibited by the differential expression of these CaM isoforms or by differences in Ca(2+) transients.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Calcio/metabolismo , Calmodulina/metabolismo , Plantas/enzimología , Isoformas de Proteínas/metabolismo , Secuencia de Aminoácidos , Animales , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , ATPasas Transportadoras de Calcio/metabolismo , Activación Enzimática
11.
Radiother Oncol ; 56(2): 175-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10927136

RESUMEN

PURPOSES: The objectives of this prospective clinical trial were to determine whether pentoxifylline improves the radiation response and survival in patients with non-small cell lung cancer. MATERIALS AND METHODS: From July 1993 through October 1994, 64 patients with histologically confirmed Stage I, II and III non-small cell lung cancer were randomly divided into pentoxifylline (Pento)+Radiotherapy (RT) group and RT alone group. Out of the 64 patients, only 47 patients who had measurable tumors on chest X-ray views were analyzed and divided into Pento+RT group (n=27) and RT alone group (n=20). Total tumor dose of 65-70 Gy was delivered as conventional fractionated radiation schedules. Pento was given to the patients 3 x 400 mg/day with a daily dose of 1200 mg during RT. RESULTS: Complete response (CR), partial response (PR), and stable in Pento+RT group were three (11%), 13 (48%), and 11 (41%), respectively, as compared with corresponding values of three (15%), 13 (65%), and four (20%) in the RT alone group. The median time to relapse in the Pento+RT group was 11 months which was 2 months longer than for the RT alone group (P>0.05). All the patients in both groups showed lower than or equal to grade 2 dysphagia, odynophagia, pulmonary fibrosis, and pneumonitis. The median survival was 18 months in the Pento+RT group and 7 months in the RT alone group. The 1-year survival rate was 60% in the Pento+RT group and 35% in the RT alone group, the 2-year survival rate was 18% in the Pento+RT group and 12% in the RT alone group. But these differences were not statistically significant (P>0.05). CONCLUSION: We concluded that Pento is a modestly effective radiation response modifier and provide benefit in the treatment of non-small cell lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Pentoxifilina/administración & dosificación , Protectores contra Radiación/administración & dosificación , Radioterapia/métodos , Anciano , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Probabilidad , Estudios Prospectivos , Radioterapia Adyuvante , Análisis de Supervivencia , Resultado del Tratamiento
12.
Plant Cell ; 12(8): 1393-407, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10948258

RESUMEN

Ca(2)+-ATPases are key regulators of Ca(2+) ion efflux in all eukaryotes. Animal cells have two distinct families of Ca(2+) pumps, with calmodulin-stimulated pumps (type IIB pumps) found exclusively at the plasma membrane. In plants, no equivalent type IIB pump located at the plasma membrane has been identified at the molecular level, although related isoforms have been identified in non-plasma membrane locations. Here, we identify a plant cDNA, designated SCA1 (for soybean Ca(2+)-ATPase 1), that encodes Ca(2+)-ATPase and is located at the plasma membrane. The plasma membrane localization was determined by sucrose gradient and aqueous two-phase membrane fractionations and was confirmed by the localization of SCA1p tagged with a green fluorescent protein. The Ca(2+)-ATPase activity of the SCA1p was increased approximately sixfold by calmodulin (K(1/2) approximately 10 nM). Two calmodulin binding sequences were identified in the N-terminal domain. An N-terminal truncation mutant that deletes sequence through the two calmodulin binding sites was able to complement a yeast mutant (K616) that was deficient in two endogenous Ca(2+) pumps. Our results indicate that SCA1p is structurally distinct from the plasma membrane-localized Ca(2+) pump in animal cells, belonging instead to a novel family of plant type IIB pumps found in multiple subcellular locations. In plant cells from soybean, expression of this plasma membrane pump was highly and rapidly induced by salt (NaCl) stress and a fungal elicitor but not by osmotic stress.


Asunto(s)
ATPasas Transportadoras de Calcio/metabolismo , Calmodulina/farmacología , Membrana Celular/enzimología , Glycine max/enzimología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sitios de Unión , Calcio/farmacología , ATPasas Transportadoras de Calcio/química , ATPasas Transportadoras de Calcio/genética , Calmodulina/metabolismo , Fraccionamiento Celular , Membrana Celular/efectos de los fármacos , Clonación Molecular , Activación Enzimática/efectos de los fármacos , Prueba de Complementación Genética , Datos de Secuencia Molecular , Especificidad de Órganos , Concentración Osmolar , Estructura Terciaria de Proteína , ARN Mensajero/análisis , ARN Mensajero/genética , ARN de Planta/análisis , ARN de Planta/genética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Sales (Química)/farmacología , Alineación de Secuencia , Eliminación de Secuencia/genética , Glycine max/citología , Glycine max/efectos de los fármacos , Levaduras/citología , Levaduras/genética , Levaduras/metabolismo
13.
Plant Physiol ; 123(1): 51-8, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10806224

RESUMEN

Fibrillarin is a nucleolar protein known to be involved in the processing of ribosomal RNA precursors. We isolated AtFbr1, a cDNA encoding a homolog of fibrillarin in Arabidopsis. The cDNA is 1.2 kb in size and encodes a polypeptide of 310 amino acid residues with a molecular mass of 33 kD. AtFbr1 is expressed at high levels in the flower and root tissue and at a slightly lower level in leaf tissue, whereas it was nearly undetectable in siliques. Expression of AtFbr1 was compared with that of the FLP (fibrillarin-like protein) gene identified by the Arabidopsis genome project. Abscisic acid treatment resulted in the down-regulation of the expression of both AtFbr1 and FLP genes in seedlings, although the degree of suppression was higher for FLP than for AtFbr1. In addition, the expression level of FLP decreased with the age of the seedlings, whereas AtFbr1 did not exhibit any detectable change. The subcellular localization of AtFbrl was studied with an in vivo targeting approach using a fusion protein, and was found to be correctly targeted to the nucleolus in protoplasts when expressed as a green fluorescent fusion protein (GFP). Deletion experiments showed that the N-terminal glycine- and arginine-rich region is necessary and sufficient to target AtFbr1 to the nucleolus.


Asunto(s)
Arabidopsis/genética , Proteínas Cromosómicas no Histona/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Complementario , Datos de Secuencia Molecular , Proteínas de Plantas/genética , Homología de Secuencia de Aminoácido
14.
Mol Plant Microbe Interact ; 13(4): 470-4, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10755311

RESUMEN

In order to study molecular interactions that occur between rice and rice blast fungus upon infection, we isolated fungal elicitor-responsive genes from rice (Oryza sativa cv. Milyang 117) suspension-cultured cells treated with fungal elicitor prepared from the rice blast fungus (Magnaporthe grisea) employing a method that combined mRNA differential display and cDNA library screening. Data base searches with the isolated cDNA clones revealed that the OsERG1 and OsERG2 cDNAs share significant similarities with the mammalian Ca2+-dependent lipid binding (C2) domains. The OsCPX1 cDNA is highly homologous to peroxidases. The OsHin1 cDNA exhibits homology to the tobacco hin1 gene, whose expression is induced by avirulent pathogens. The OsLPL1 and OsMEK1 cDNAs share homologies with lysophospholipases and serine/threonine mitogen-activated protein (MAP) kinase kinases, respectively. The OsWRKY1 and OsEREBP1 cDNAs are homologous to transcription factors, such as the WRKY protein family and the AP2/EREBP family, respectively. Transcripts of the OsERG1, OsHin1, and OsMEK1 genes were specifically elevated only in response to the avirulent race KJ301 of the rice blast fungus. Our study yielded a number of elicitor-responsive genes that will not only provide molecular probes, but also contribute to our understanding of host defense mechanisms against the rice blast fungus.


Asunto(s)
Magnaporthe/patogenicidad , Oryza/metabolismo , Proteínas de Plantas/metabolismo , ARN de Planta/metabolismo , Transducción de Señal/genética , Northern Blotting , Células Cultivadas , Oryza/microbiología , Proteínas de Plantas/análisis , ARN Mensajero/análisis , ARN de Planta/análisis , Virulencia
15.
Anticancer Res ; 20(6B): 4605-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11205310

RESUMEN

The aim of this study was to investigate whether multiple injections (daily for 5 days) of the hemorheological agent pentoxifylline (PTX) affected tumor physiological parameters (i.e., tumor pO2, tumor pH, and tumor interstitial fluid pressure) during the tumor growth of FSaII murine fibrosarcoma in C3H mice. The radiation sensitization by multiple injections of PTX (daily for 5 days) was also studied. Following multiple administrations of PTX, PTX significantly improved tumor oxygenation in all sizes of tumors tested. Our results showed that the elevated tumor interstitial fluid pressure (TIFP) in solid tumors could be reduced by PTX. Based on our results with the improvement in tumor pathophysiology, PTX may be of use during tumor therapies in which the outcome may be detrimentally affected by the presence of hypoxia. As anticipated, multiple injections of PTX with fractionated x-irradiation prolonged the radiation-induced growth delay in FSaII tumors, producing an enhancement ratio of 1.8 of the growth delay at 15 days. However, we did not observe any alteration in cellular oxygen consumption (QO2) after the treatment with PTX. Therefore, we concluded that PTX-induced radiosensitization was due to an increase in tumor pO2, not a reduction in QO2.


Asunto(s)
Hipoxia de la Célula/efectos de los fármacos , Espacio Extracelular/efectos de los fármacos , Fibrosarcoma/fisiopatología , Fármacos Hematológicos/farmacología , Consumo de Oxígeno/efectos de los fármacos , Pentoxifilina/farmacología , Protectores contra Radiación/farmacología , Animales , Hipoxia de la Célula/efectos de la radiación , Deformación Eritrocítica/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Eritrocitos/fisiología , Espacio Extracelular/fisiología , Femenino , Fibrosarcoma/irrigación sanguínea , Fibrosarcoma/radioterapia , Fármacos Hematológicos/administración & dosificación , Concentración de Iones de Hidrógeno/efectos de los fármacos , Ratones , Ratones Endogámicos C3H , Consumo de Oxígeno/efectos de la radiación , Pentoxifilina/administración & dosificación , Tolerancia a Radiación/efectos de los fármacos , Protectores contra Radiación/administración & dosificación , Dosificación Radioterapéutica
16.
Plant Mol Biol ; 40(5): 825-34, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10487217

RESUMEN

A cDNA (C2C-Prx) corresponding to a 2Cys-peroxiredoxin (2Cys-Prx) was isolated from a leaf cDNA library of Chinese cabbage. The predicted amino acid sequence of C2C-Prx has 2 conserved cysteines and several peptide domains present in most of the 2Cys-Prx subfamily members. It shows the highest sequence homology to the 2Cys-Prx enzymes of spinach (88%) and Arabidopsis (86%). Southern analysis using the cDNA insert of C2C-Prx revealed that it consists of a small multigene family in Chinese cabbage genome. RNA blot analysis showed that the gene was predominantly expressed in the leaf tissue of Chinese cabbage seedlings, but the mRNA was generally expressed in most tissues of mature plant, except roots. The expression of C2C-Prx was slightly induced by treatment with H2O2 (100 microM) or Fe3+/O2/DTT oxidation system, but not by ABA (50 microM) or GA3 (10 microM). The C2C-Prx is encoded as a preprotein of 273 amino acids containing a putative chloroplast-targeting signal of 65 amino acids at its N-terminus. The N-terminally truncated recombinant protein (deltaC2C-Prx) migrates as a dimer in a non-reducing SDS-polyacrylamide gel and as a monomer in a reducing condition. The deltaC2C-Prx shows no immuno cross-reactivity to antiserum of the yeast thiol-specific antioxidant protein, and vice versa. The deltaC2C-Prx prevents the inactivation of glutamine synthetase and the DNA cleavage in the metal-catalyzed oxidation system. In the yeast thioredoxin system containing thioredoxin reductase, thioredoxin, and NADPH, the deltaC2C-Prx exhibits peroxidase activity on H2O2.


Asunto(s)
Brassica/enzimología , Brassica/genética , Peroxidasas/genética , Secuencia de Aminoácidos , Animales , Arabidopsis/genética , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , Cisteína , Regulación de la Expresión Génica de las Plantas , Glutamato-Amoníaco Ligasa/metabolismo , Humanos , Cinética , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Peroxidasas/biosíntesis , Peroxidasas/química , Peroxirredoxinas , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Spinacia oleracea/enzimología
17.
Helicobacter ; 4(2): 77-81, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10382119

RESUMEN

BACKGROUND: Helicobacter pylori has generally been observed only in the gastric mucous layer or in the spaces between gastric mucus-secreting cells and not in the gastric epithelial cells or in the lamina propria. The purpose of this study is to determine whether H. pylori invades the gastric mucosa, using an immunoelectron microscopical examination of human gastric mucosa infected with H. pylori. MATERIALS AND METHODS: Five hundred gastric antral biopsy specimens were fixed in a periodate-lysin-paraformaldehyde solution, embedded in Lowicryl, sectioned, and examined with a light microscope. One hundred specimens moderately or severely infected with H. pylori were selected and were incubated with polyclonal rabbit anti-H. pylori antibody. The specimens were washed, incubated with 20 nm of colloidal gold-conjugated goat anti-rabbit IgG, stained with uranyl acetate and lead citrate, and observed with a transmission electron microscope. RESULTS: In one case, a bacterium was observed within the cytoplasm of a gastric mucus-secreting cell; in another case, a few bacteria were observed within the cytoplasm of a stromal cell in the lamina propria. The bacteria could be differentiated from degenerated intracellular organelles by gold particles attached to the bacteria. CONCLUSION: H. pylori rarely invade the lamina propria and gastric cells.


Asunto(s)
Mucosa Gástrica/microbiología , Helicobacter pylori/patogenicidad , Antro Pilórico/microbiología , Adulto , Biopsia , Mucosa Gástrica/ultraestructura , Helicobacter pylori/ultraestructura , Humanos , Microscopía Inmunoelectrónica , Antro Pilórico/ultraestructura
18.
Radiology ; 211(1): 183-7, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10189469

RESUMEN

PURPOSE: To clarify the natural history of primary lymphoma of the small bowel and identify preferred treatments for it. MATERIALS AND METHODS: A retrospective analysis of 61 patients with primary lymphoma of the small bowel was performed. The Ann Arbor stages were I in 20 patients, II in 28, and IV in 13. After resection or biopsy, 15 patients were treated with radiation therapy, 26 with chemotherapy, and 16 with combined-modality therapy. Four patients underwent no adjuvant treatment after resection. RESULTS: The actuarial 10-year overall survival and relapse-free survival for the patients with intermediate- and high-grade lymphoma were 47% and 53%, respectively. For the patients with low-grade lymphoma, these rates were 81% and 62%. For patients who underwent radiation therapy, combined-modality therapy, or chemotherapy, the recurrence rates inside the abdomen or pelvis were one of 12, two of 15, and five of 20, respectively, and those outside the abdomen or pelvis were four of 12, one of 15, and zero of 20, respectively. Four of the five abdominopelvic recurrences of disease in the chemotherapy group were among the nine patients who had Ann Arbor stage II disease. CONCLUSION: Chemotherapy lowered the recurrence rate outside the abdomen or pelvis. Patients with stage II disease may benefit most from radiation therapy.


Asunto(s)
Neoplasias Intestinales/epidemiología , Intestino Delgado , Linfoma no Hodgkin/epidemiología , Antineoplásicos/uso terapéutico , Terapia Combinada , Bases de Datos Factuales , Femenino , Humanos , Neoplasias Intestinales/terapia , Linfoma no Hodgkin/terapia , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Pronóstico , Dosificación Radioterapéutica , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
19.
Proc Natl Acad Sci U S A ; 96(2): 766-71, 1999 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-9892708

RESUMEN

The Ca2+ signal is essential for the activation of plant defense responses, but downstream components of the signaling pathway are still poorly defined. Here we demonstrate that specific calmodulin (CaM) isoforms are activated by infection or pathogen-derived elicitors and participate in Ca2+-mediated induction of plant disease resistance responses. Soybean CaM (SCaM)-4 and SCaM-5 genes, which encode for divergent CaM isoforms, were induced within 30 min by a fungal elicitor or pathogen, whereas other SCaM genes encoding highly conserved CaM isoforms did not show such response. This pathogen-triggered induction of these genes specifically depended on the increase of intracellular Ca2+ level. Constitutive expression of SCaM-4 and SCaM-5 in transgenic tobacco plants triggered spontaneous induction of lesions and induces an array of systemic acquired resistance (SAR)-associated genes. Surprisingly, these transgenic plants have normal levels of endogenous salicylic acid (SA). Furthermore, coexpression of nahG gene did not block the induction of SAR-associated genes in these transgenic plants, indicating that SA is not involved in the SAR gene induction mediated by SCaM-4 or SCaM-5. The transgenic plants exhibit enhanced resistance to a wide spectrum of virulent and avirulent pathogens, including bacteria, fungi, and virus. These results suggest that specific CaM isoforms are components of a SA-independent signal transduction chain leading to disease resistance.


Asunto(s)
Calcio/farmacología , Calmodulina/genética , Regulación de la Expresión Génica de las Plantas/genética , Glycine max/metabolismo , Inmunidad Innata/genética , Enfermedades de las Plantas , Ácido Salicílico/metabolismo , Fusarium/patogenicidad , Genes de Plantas/genética , Fenotipo , Phytophthora/patogenicidad , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Plantas Tóxicas , Pseudomonas/patogenicidad , Nicotiana/genética , Nicotiana/microbiología , Activación Transcripcional
20.
Nucleosides Nucleotides ; 17(6): 1089-98, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9708324

RESUMEN

Bis(pivaloyloxymethyl) ester of 2'-azido-2'-deoxyuridine 5'-monophosphate was prepared as a prodrug to generate 2'-azido-2'-deoxyuridine 5'-diphosphate inside the cell. A synthetic route utilizing stannyl phosphate was adopted in the preparation. The prodrug was evaluated for cell growth inhibition against a variety of tumor cell lines along with 2'-azido-2'-deoxyuridine and 2'-azido-2'-deoxycytidine.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Azidas/síntesis química , Azidas/farmacología , Nucleótidos de Desoxiuracil/síntesis química , Nucleótidos de Desoxiuracil/farmacología , Animales , Células CHO , Cricetinae , Ensayos de Selección de Medicamentos Antitumorales , Espectroscopía de Resonancia Magnética , Células Tumorales Cultivadas
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