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1.
Phys Rev Lett ; 111(6): 067601, 2013 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-23971612

RESUMEN

We report the detection and polarization of nuclear spins in diamond at room temperature by using a single nitrogen-vacancy (NV) center. We use Hartmann-Hahn double resonance to coherently enhance the signal from a single nuclear spin while decoupling from the noisy spin bath, which otherwise limits the detection sensitivity. As a proof of principle, we (i) observe coherent oscillations between the NV center and a weakly coupled nuclear spin and (ii) demonstrate nuclear-bath cooling, which prolongs the coherence time of the NV sensor by more than a factor of 5. Our results provide a route to nanometer scale magnetic resonance imaging and novel quantum information processing protocols.


Asunto(s)
Espectroscopía de Resonancia Magnética , Modelos Teóricos , Física Nuclear/métodos , Electrones , Nitrógeno/química
2.
Microsc Microanal ; 18(5): 1030-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23058452

RESUMEN

Adenosine triphosphate (ATP) is a well-known energy source for muscle contraction. In this study, to visualize localization of ATP, a luciferin-luciferase reaction (LLR) was performed in mouse skeletal muscle with an "in vivo cryotechnique" (IVCT). First, to confirm if ATP molecules could be trapped and detected after glutaraldehyde (GA) treatment, ATP was directly attached to glass slides with GA, and LLR was performed. The LLR was clearly detected as an intentional design of the ATP attachment. The intensity of the light unit by LLR was correlated with the concentration of the GA-treated ATP in vitro. Next, LLR was evaluated in mouse skeletal muscles with IVCT followed by freeze-substitution fixation (FS) in acetone-containing GA. In such tissue sections the histological structure was well maintained, and the intensity of LLR in areas between muscle fibers and connective tissues was different. Moreover, differences in LLR among muscle fibers were also detected. For the IVCT-FS tissue sections, diaminobenzidine (DAB) reactions were clearly detected in type I muscle fibers and erythrocytes in capillaries, which demonstrated flow shape. Thus, it became possible to perform microscopic evaluation of the numbers of ATP molecules in the mouse skeletal muscles with IVCT, which mostly reflect living states.


Asunto(s)
Adenosina Trifosfato/análisis , Luciferina de Luciérnaga/metabolismo , Substitución por Congelación/métodos , Luciferasas/metabolismo , Músculo Esquelético/química , Adenosina Trifosfato/metabolismo , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/citología , Músculo Esquelético/metabolismo
3.
Scand J Immunol ; 71(6): 447-51, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20500697

RESUMEN

We identify possible differences in the cytokine/chemokine profiles in cerebrospinal fluid (CSF) from children with encephalopathy and febrile seizure. Interleukin (IL)-1beta, 2, 4, 5, 6, 7, 8, 10, 12, 13, 17, interferon-gamma, tumour necrosis factor-alpha, granulocyte colony-stimulating factor, granulocyte monocyte colony-stimulating factor, monocyte chemoattractant protein-1 and macrophage inflammatory protein-1beta were measured simultaneously in CSF supernatants from children with encephalopathy (n = 8), febrile seizure (n = 16) and fever without neurological complications (n = 8). IL-8 in CSF from children with encephalopathy was significantly elevated compared to that in CSF from children with febrile seizure and fever without neurological complications. IL-8 in CSF was also higher than serum IL-8, suggesting that increased IL-8 was generated from glia cells or astrocytes, not by leakage from serum. Increased IL-8 in CSF in encephalopathy may protect against severe brain damage.


Asunto(s)
Encefalitis/líquido cefalorraquídeo , Encefalitis/inmunología , Interleucinas/líquido cefalorraquídeo , Convulsiones Febriles/líquido cefalorraquídeo , Convulsiones Febriles/inmunología , Quimiocina CCL2/líquido cefalorraquídeo , Quimiocina CCL2/inmunología , Quimiocina CCL4/líquido cefalorraquídeo , Quimiocina CCL4/inmunología , Preescolar , Femenino , Factor Estimulante de Colonias de Granulocitos/líquido cefalorraquídeo , Factor Estimulante de Colonias de Granulocitos/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/líquido cefalorraquídeo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Humanos , Inmunoensayo , Lactante , Interferón gamma/líquido cefalorraquídeo , Interferón gamma/inmunología , Interleucinas/inmunología , Masculino , Estadísticas no Paramétricas , Factor de Necrosis Tumoral alfa/líquido cefalorraquídeo , Factor de Necrosis Tumoral alfa/inmunología
4.
Theor Appl Genet ; 121(7): 1357-67, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20589366

RESUMEN

DNA markers that allow for identification of resistance genes in rice germplasm have a great advantage in resistance breeding because they can assess the existence of the genes without laborious inoculation tests. Functional markers (FMs), which are designed from functional polymorphisms within the sequence of genes, are unaffected by nonfunctional allelic variation and make it possible to identify an individual gene. We previously showed that the resistance function of the rice blast resistance gene Pit in a resistant cultivar, K59, was mainly acquired by up-regulated promoter activity through the insertion of a long terminal repeat (LTR) retrotransposon upstream of Pit. Here, we developed PCR-based DNA markers derived from the LTR-retrotransposon sequence and used these markers to screen worldwide accessions of rice germplasm. We identified 5 cultivars with the LTR-retrotransposon insertion out of 68 rice accessions. The sequence and expression pattern of Pit in the five cultivars were the same as those in K59 and all showed Pit-mediated blast resistance. The results suggest that the functional Pit identified using the markers was derived from a common progenitor. Additionally, comparison of the Pit coding sequences between K59 and susceptible cultivars revealed that one nucleotide polymorphism, which caused an amino acid substitution, offered another target for a FM. These results indicate that our DNA markers should enhance prediction of Pit function and be applicable to a range of rice varieties/landraces cultivated in various regions worldwide and belonging to the temperate japonica, tropical japonica, and indica groups.


Asunto(s)
Marcadores Genéticos , Genoma de Planta , Oryza/genética , Inmunidad de la Planta/genética , Secuencias Repetidas Terminales/genética , Alelos , Secuencia de Aminoácidos , Secuencia de Bases , Cruzamiento , Genotipo , Geografía , Magnaporthe/patogenicidad , Enfermedades de las Plantas/genética , Mutación Puntual , Polimorfismo Genético , Retroelementos/genética
5.
Science ; 292(5523): 1899-901, 2001 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-11397942

RESUMEN

We report the realization of an ultraviolet light-emitting diode with the use of a diamond pn junction. The pn junction was formed from a boron-doped p-type diamond layer and phosphorus-doped n-type diamond layer grown epitaxially on the 111 surface of single crystalline diamond. The pn junction exhibited good diode characteristics, and at forward bias of about 20 volts strong ultraviolet light emission at 235 nanometers was observed and was attributed to free exciton recombination.

6.
Thorac Cardiovasc Surg ; 57(5): 311-2, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19629898

RESUMEN

Airway obstruction by retropharyngeal or cervicomediastinal hematomas following stellate ganglion block is life-threatening. The onset of the initial symptoms of retropharyngeal or cervicomediastinal hematoma usually occurs 2 hours or more after stellate ganglion block. We report the rare complication of airway obstruction leading to respiratory arrest caused by retropharyngeal and cervicomediastinal hematomas due to rebleeding of an ascending cervical artery 3 days after stellate ganglion block.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Bloqueo Nervioso Autónomo/efectos adversos , Vértebras Cervicales/irrigación sanguínea , Hematoma/etiología , Hemorragia/etiología , Enfermedades del Mediastino/etiología , Enfermedades Faríngeas/etiología , Ganglio Estrellado , Arteria Vertebral/lesiones , Obstrucción de las Vías Aéreas/diagnóstico por imagen , Obstrucción de las Vías Aéreas/terapia , Parálisis Facial/terapia , Femenino , Hematoma/diagnóstico por imagen , Hematoma/terapia , Hemorragia/diagnóstico por imagen , Hemorragia/terapia , Humanos , Enfermedades del Mediastino/diagnóstico por imagen , Enfermedades del Mediastino/terapia , Persona de Mediana Edad , Enfermedades Faríngeas/diagnóstico por imagen , Enfermedades Faríngeas/terapia , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
7.
Neuron ; 22(1): 125-37, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10027295

RESUMEN

Elementary Ca2+ release signals in nerve growth factor- (NGF-) differentiated PC12 cells and hippocampal neurons, functionally analogous to the "Ca2+ sparks" and "Ca2+ puffs" identified in other cell types, were characterized by confocal microscopy. They either occurred spontaneously or could be activated by caffeine and metabotropic agonists. The release events were dissimilar to the sparks and puffs described so far, as many arose from clusters of both ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors (InsP3Rs). Increasing either the stimulus strength or loading of the intracellular stores enhanced the frequency of and coupling between elementary release sites and evoked global Ca2+ signals. In the PC12 cells, the elementary Ca2+ release preferentially occurred around the branch points. Spatio-temporal recruitment of such elementary release events may regulate neuronal activities.


Asunto(s)
Señalización del Calcio/fisiología , Hipocampo/fisiología , Factores de Crecimiento Nervioso/farmacología , Neuronas/fisiología , Células PC12/patología , Células PC12/fisiología , Animales , Calcio/metabolismo , Canales de Calcio/metabolismo , Canales de Calcio/fisiología , Diferenciación Celular/efectos de los fármacos , Electrofisiología , Retículo Endoplásmico/metabolismo , Hipocampo/citología , Receptores de Inositol 1,4,5-Trifosfato , Neuritas/metabolismo , Ratas , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores Citoplasmáticos y Nucleares/fisiología , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/fisiología
8.
Int J Biol Markers ; 23(3): 182-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18949745

RESUMEN

The aim of this study was to evaluate periostin expression measured immunohistochemically in patients with non-small cell lung cancer (NSCLC) and to determine its association with clinical features, prognosis, angiogenesis, and lymphangiogenesis. We investigated periostin expression in a series of 88 patients with NSCLC. We also determined whether expression of periostin correlated with microvessel density and lymphatic microvessel density. Periostin was expressed in 42% of 88 patients. Its expression was significantly correlated with tumor size, lymph node metastasis, disease stage, and lymphatic invasion (p=0.0128, 0.0015, 0.0310 and 0.0273, respectively). There also was a significant relation between periostin expression and microvessel density and lymphatic microvessel density (all p<0.0001). Five-year survival rates were better in patients with negative periostin expression than in those with positive periostin expression (p=0.0044). Periostin expression was not significant in a multivariate additive model. Our findings show that periostin correlates with increased tumor progression and a worse prognosis in NSCLC, as well as with angiogenesis and lymphangiogenesis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Moléculas de Adhesión Celular/biosíntesis , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/metabolismo , Linfangiogénesis , Neovascularización Patológica , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica/métodos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
9.
Phytopathology ; 98(2): 159-66, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18943192

RESUMEN

Members of the Fusarium graminearum species complex are important cereal pathogens worldwide and belong to one of at least nine phylogenetically distinct species. We examined 298 strains of the F. graminearum species complex collected from wheat or barley in Japan to determine the species and trichothecene chemotype. Phylogenetic analyses and species-diagnostic polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLPs) revealed the presence and differential distribution of F. graminearum sensu stricto (s. str.) and F. asiaticum in Japan. F. graminearum s. str. is predominant in the north, especially in the Hokkaido area, while F. asiaticum is predominant in southern regions. In the Tohoku area, these species co-occurred. Trichothecene chemotyping of all strains by multiplex PCR revealed significantly different chemotype compositions of these species. All 50 strains of F. graminearum s. str. were of a 15- or 3-acetyl deoxynivalenol type, while 173 (70%) out of 246 strains of F. asiaticum were of a nivalenol type. The possibility of gene flow between the two species was investigated by use of 15 PCR-RFLP markers developed in this study. However, no obvious hybrids were detected from 98 strains examined, including strains collected from regions where both species co-occur.


Asunto(s)
ADN de Hongos/genética , Fusarium/genética , Enfermedades de las Plantas/microbiología , Fusarium/clasificación , Fusarium/aislamiento & purificación , Geografía , Hordeum/microbiología , Japón , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Triticum/microbiología
10.
Eur Surg Res ; 40(3): 247-55, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18057903

RESUMEN

BACKGROUND/AIM: Ischemic preconditioning (IPC) may reduce hepatic ischemia-reperfusion (IR) injury, but efficacy of IPC on mitochondrial proteome is not demonstrated. We investigated how IPC modifies the mitochondrial proteome after IR injury. METHODS: Rats were subjected to 25 min of portal triad crossclamping (IR group, n = 8). In the IPC group (n = 8), 10 min of temporal portal triad clamping was performed before 25 min of portal clamping. Samples were obtained after 24 h. The mitochondrial inner-membrane potential was measured by the uptake of a lipophilic cationic carbocyanine probe and mitochondrial proteome was also investigated using 2-dimensional differential in-gel electrophoresis and liquid chromatography-tandem mass spectrometry. RESULTS: Mitochondrial inner-membrane potential and glutathione were lower and serum transaminase was higher in the IPC group than in the IR group. The mitochondrial precursor of aldehyde dehydrogenase 2 and alpha-methylacyl-CoA-racemase were upregulated in the IPC group in comparison to the IR group. In contrast, protein disulfide-isomerase A3 precursor, 60S acid ribosomal protein P0, carbonic anhydrase 3 and superoxide dismutase were significantly more downregulated in the IPC group than in the IR group. CONCLUSIONS: A hepatoprotective effect by IPC was not shown; however, IPC caused significant up- or downregulation of several mitochondrial proteins.


Asunto(s)
Precondicionamiento Isquémico , Hepatopatías/prevención & control , Mitocondrias Hepáticas/fisiología , Proteoma/fisiología , Daño por Reperfusión/prevención & control , Animales , Modelos Animales de Enfermedad , Hepatopatías/fisiopatología , Masculino , Ratas , Ratas Wistar , Daño por Reperfusión/fisiopatología
11.
Kyobu Geka ; 61(10): 873-6, 2008 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-18788378

RESUMEN

We report 2 cases of resected CA19-9 producing adenocarcinoma of the lung. Immunohistochemical studies of the specimens in 2 cases showed positive staining for CA19-9 in most of tumor cells. The serum CA19-9 levels decreased after operations and effective chemotherapy in these cases. But the serum CA19-9 levels increased with regrowth of tumors or with no therapeutic gain by chemotherapy. The serum CA19-9 level was useful to evaluate the therapeutic effect of surgery and chemotherapy, and may be effective in detecting the recurrence of lung cancer.


Asunto(s)
Adenocarcinoma/metabolismo , Adenocarcinoma/cirugía , Biomarcadores de Tumor/biosíntesis , Antígeno CA-19-9/biosíntesis , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/cirugía , Neumonectomía , Adenocarcinoma/diagnóstico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Carboplatino/administración & dosificación , Terapia Combinada , Docetaxel , Resultado Fatal , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Taxoides/administración & dosificación , Resultado del Tratamiento
12.
J Clin Invest ; 103(1): 129-35, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9884342

RESUMEN

The first known human case of heme oxygenase-1 (HO-1) deficiency is presented in this report. The patient is a six-year-old boy with severe growth retardation. He has been suffering from persistent hemolytic anemia characterized by marked erythrocyte fragmentation and intravascular hemolysis, with paradoxical increase of serum haptoglobin and low bilirubin. An abnormal coagulation/fibrinolysis system, associated with elevated thrombomodulin and von Willebrand factor, indicated the presence of severe, persistent endothelial damage. Electron microscopy of renal glomeruli revealed detachment of endothelium, with subendothelial deposition of an unidentified material. Iron deposition was noted in renal and hepatic tissue. Immunohistochemistry of hepatic tissue and immunoblotting of a cadmium-stimulated Epstein-Barr virus-transformed lymphoblastoid cell line (LCL) revealed complete absence of HO-1 production. An LCL derived from the patient was extremely sensitive to hemin-induced cell injury. Sequence analysis of the patient's HO-1 gene revealed complete loss of exon-2 of the maternal allele and a two-nucleotide deletion within exon3 of the paternal allele. Growth retardation, anemia, iron deposition, and vulnerability to stressful injury are all characteristics observed in recently described HO-1 targeted mice. This study presents not only the first human case of HO-1 deficiency but may also provide clues to the key roles played by this important enzyme in vivo.


Asunto(s)
Hemo Oxigenasa (Desciclizante)/deficiencia , Estrés Oxidativo/genética , Animales , Cadmio/farmacología , Línea Celular , Niño , Análisis Mutacional de ADN , Modelos Animales de Enfermedad , Hemo Oxigenasa (Desciclizante)/genética , Hemo-Oxigenasa 1 , Hemina/metabolismo , Hemina/toxicidad , Histocitoquímica , Humanos , Inmunohistoquímica , Glomérulos Renales/patología , Hígado/patología , Masculino , Proteínas de la Membrana , Ratones , Ratones Noqueados , Microscopía Electrónica , Monocitos , ARN Mensajero/genética
13.
J Clin Invest ; 75(3): 1008-14, 1985 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2579975

RESUMEN

Immature myeloid precursor cells were preferentially selected from normal human bone marrow by using immune rosette techniques that employed monoclonal antibodies against mature granulocytes, monocytes, T and B lymphocytes, and erythroid precursors (Mo5, M3, OKT3, B1, and EP1, respectively). We examined the formation, retention, and cytotoxic effects of methotrexate (MTX) polyglutamates (MTX-PGs) in these purified myeloid precursor cells. After 1- and 24-h exposures to MTX, with thymidine and deoxyinosine as rescue, the intracellular MTX-PG profile was examined by high-pressure liquid chromatography. Efflux patterns of MTX-PGs were also studied after additional 1- and 24-h incubations in drug-free media. Cytotoxic effects of retained MTX-PGs on bone marrow myeloid precursors were examined by colony formation in drug-free semisolid agar. Normal myeloid precursor cells converted MTX to MTX-PGs in a concentration- and time-dependent manner, preferentially retaining MTX-PGs with three to five glutamyl moieties. At low concentrations of MTX (1 microM), MTX-PG formation was insufficient to maintain saturation of the target enzyme dihydrofolate reductase after removal of drug from the incubation medium, and there was no decrease in myeloid colony formation. At higher concentrations of MTX (10 microM), formation of higher molecular weight polyglutamates was sufficient to allow for 24-h saturation of intracellular binding capacity after removal of extracellular drug and resulted in a 35% reduction in the formation of colony-forming units in culture. Comparison of MTX metabolism in normal bone marrow cells and the MTX-sensitive HL-60 human leukemia cell line showed twofold greater PG formation by these tumor cells after 24-h exposure to 1 or 10 microM MTX, and a marked (greater than 30-fold) increase in cytotoxicity for the HL-60 cells as compared with normal myeloid precursors, suggesting that the MTX polyglutamation may be important to its selective antitumor action.


Asunto(s)
Células de la Médula Ósea , Células Madre Hematopoyéticas/metabolismo , Metotrexato/análogos & derivados , Péptidos/metabolismo , Ácido Poliglutámico/metabolismo , Médula Ósea/metabolismo , Línea Celular , Separación Celular/métodos , Supervivencia Celular/efectos de los fármacos , Ensayo de Unidades Formadoras de Colonias , Inhibidores de Crecimiento/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Inosina , Líquido Intracelular/metabolismo , Leucemia Mieloide Aguda/metabolismo , Metotrexato/metabolismo , Metotrexato/farmacología , Ácido Poliglutámico/análogos & derivados , Ácido Poliglutámico/farmacología , Timidina
14.
Neuroscience ; 147(1): 153-63, 2007 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-17521827

RESUMEN

Retinoic acids (RAs), including all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9-cis RA), play fundamental roles in a variety of physiological events in vertebrates, through their specific nuclear receptors: retinoic acid receptor (RAR) and retinoid X receptor (RXR). Despite the physiological importance of RA, their functional significance under pathological conditions is not well understood. We examined the effect of ATRA on oxygen/glucose-deprivation/reperfusion (OGD/Rep)-induced neuronal damage in cultured rat hippocampal slices, and found that ATRA significantly reduced neuronal death. The cytoprotective effect of ATRA was observed not only in cornu ammonis (CA) 1 but also in CA2 and dentate gyrus (DG), and was attenuated by selective antagonists for RAR or RXR. By contrast, in the CA3 region, no protective effects of ATRA were observed. The OGD/Rep also increased phosphorylated forms of c-jun-N-terminal kinase (P-JNK) and p38 (P-p38) in hippocampus, and specific inhibitors for these kinases protected neurons. ATRA prevented the increases in P-JNK and P-p38 after OGD/Rep, as well as the decrease in NeuN and its shrinkage, all of which were inhibited by antagonists for RAR or RXR. These findings suggest that the ATRA signaling via retinoid receptors results in the inhibition of JNK and p38 activation, leading to the protection of neurons against OGD/Rep-induced damage in the rat hippocampus.


Asunto(s)
Hipocampo/enzimología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Neuronas/enzimología , Tretinoina/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Análisis de Varianza , Animales , Glucemia/metabolismo , Muerte Celular/fisiología , Inhibidores Enzimáticos/metabolismo , Hipocampo/patología , Hipoxia/enzimología , Técnicas In Vitro , Neuronas/patología , Ratas , Ratas Wistar , Receptores de Ácido Retinoico/metabolismo , Daño por Reperfusión/enzimología , Daño por Reperfusión/prevención & control , Transducción de Señal/fisiología , Estadísticas no Paramétricas
15.
Mol Cell Biol ; 9(10): 4398-401, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2586515

RESUMEN

Strain d48 of Paramecium tetraurelia contains the A i-antigen gene in the micronucleus, but the gene is lost when micronuclear products develop into the macronucleus. It has recently been shown that when injected into d48, macronucleoplasm from the wild type transforms d48 cells to wild type. It is shown here that wild-type cytoplasm can also bring about transformation, with a marked stage-specific sensitivity for both donor and recipient. It was also found that a plasmid containing the cloned A gene could transform d48 to wild type. Injection of nucleoplasm from animals in the vegetative stage of the cell cycle into the cytoplasm of recipients at various stages of autogamy caused high-frequency transformation of cells able to express the A serotype both before and after the next autogamy. Injection of nucleoplasm into vegetative macronuclei produced over 70% transformants able to express the A serotype after the next autogamy. The ability of nucleoplasm to transform was acquired at the second cell cycle after autogamy and was maintained throughout the vegetative stage. When cytoplasm was obtained from donors during autogamy and injected into the cytoplasm of recipients 1 to 2 h after the sensitive period, quite high frequencies of stable revertants were found when tested both before and after the next autogamy. Cells that were injected into the macronucleus with the cloned A plasmid expressed the A serotype after five fissions in over 20% of the lines and maintained this ability through successive fissions; all transformants except one stably expressed the A serotype even after the next autogamy.


Asunto(s)
Antígenos de Protozoos , Antígenos de Superficie/fisiología , Núcleo Celular/fisiología , Paramecium/genética , Proteínas Protozoarias , Animales , Antígenos de Superficie/genética , Citoplasma/fisiología , Microinyecciones , Paramecium/ultraestructura , Plásmidos
16.
Mol Cell Biol ; 10(3): 1249-53, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2137553

RESUMEN

Phosphorylation of the human ets-2 protein in response to mitogenic signals to T lymphocytes was investigated in Jurkat cells. Activation of the cells by antibodies against the T-cell antigen receptor-CD3 complex or by concanavalin A was followed within 5 min by increased phosphorylation of the protein, as shown by a mobility shift of the protein from 54 to 56 kilodaltons in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and increased incorporation of 32P. The Ca2+ ionophores A23187 and ionomycin were able to mimic this effect, suggesting that this phosphorylation is mediated by Ca2+.


Asunto(s)
Antígenos de Diferenciación de Linfocitos T/fisiología , Proteínas de Unión al ADN , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Receptores de Antígenos de Linfocitos T/fisiología , Proteínas Represoras , Linfocitos T/metabolismo , Transactivadores , Factores de Transcripción , Complejo CD3 , Calcio/fisiología , Humanos , Técnicas In Vitro , Activación de Linfocitos , Peso Molecular , Fosforilación , Fosfoserina/metabolismo , Proteína Quinasa C/fisiología , Proteína Proto-Oncogénica c-ets-2 , Transducción de Señal , Células Tumorales Cultivadas
17.
Curr Opin Struct Biol ; 10(5): 536-41, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11042450

RESUMEN

Rapid advances in the cloning and expression of glycosyltransferase genes, especially from bacteria, could open the way to overcoming difficulties in the mass production of oligosaccharides. The large-scale production of oligosaccharides using either glycosyltransferases isolated from engineered microorganisms or whole cells as an enzyme source could promote a new era in the field of carbohydrate synthesis.


Asunto(s)
Bacterias/genética , Glicosiltransferasas/metabolismo , Oligosacáridos/biosíntesis , Glicosiltransferasas/genética , Oligosacáridos/genética
18.
Clin Nephrol ; 68(5): 315-21, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18044264

RESUMEN

BACKGROUND: We report a 16 year-old girl with propylthiouracil (PTU)-induced antineutrophil cytoplasmic antibody (ANCA)-positive glomerulonephritis combined with Henoch-Schönlein purpura nephritis (HSPN) and antiphospholipid syndrome (APS). CASE AND METHODS: The patient had Graves' disease and had been treated with PTU for about 6 years. She complained of arthralgia, epigastralgia, purpura of the lower extremities, anemia, and abnormal urinalysis. Lupus anticoagulant was positive. Additionally, a high level of anti-myeloperoxidase (MPO) antibodies (IgG) and a low level of coagulation factor XIII were recognized. She had several complications including lung bleeding, lacuna infarctions of the right frontal and parietal brain lobes, and deep vein thrombosis of the left lower extremity. We studied tissue histology and carried out MPO-ANCA subtype analysis by immunofluorescence and flow cytometry and MPO-ANCA epitope analysis. RESULTS: Histologically, purpura showed leukocytoclastic vasculitis with perivascular depositions of IgA and complement C3. Renal biopsy showed necrotizing glomerulonephritis with crescents and mesangial IgA deposits. Notably, IgG, IgM, and IgA ANCA were detected in the patient's serum by flow cytometry and immunofluorescence. We diagnosed an overlap syndrome of ANCA-positive vasculitis, HSPN, and APS. A change in the reactivity of MPO-ANCA from recognition of only the Hg epitope in the C-terminal region to recognition of multiple MPO epitopes was accompanied by a remission of symptoms. CONCLUSIONS: This report may provide a very rare description of an overlap syndrome of PTU-induced ANCA vasculitis, HSPN, and APS in which not only IgG ANCA but also IgA and IgM ANCA were found. Epitope analysis may be a useful marker for disease-monitoring of PTU-induced ANCA-positive vasculitis. This case may provide insight into the pathological mechanism underlying each of these diseases.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/análisis , Peroxidasa/análisis , Propiltiouracilo/efectos adversos , Vasculitis/inducido químicamente , Vasculitis/complicaciones , Niño , Epítopos , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Glomérulos Renales/enzimología , Glomérulos Renales/patología
19.
Phytopathology ; 97(5): 598-602, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-18943579

RESUMEN

ABSTRACT Partial resistance to rice blast in the Oryza sativa japonica group cv. Chubu 32 is controlled by Pi34, a major quantitative trait locus (QTL) on chromosome 11, and several uncharacterized QTLs. The objectives of the study were (i) high-resolution genetic and physical mapping of Pi34 and (ii) identification of new QTL imparting resistance to rice blast. Chubu 32 was crossed with a susceptible chromosomal segment substitution line (CSSL) of cv. Koshihikari. From 4,012 of segregating individuals, 213 recombinants in the Pi34 region were screened by using polymerase chain reaction-based markers and tested resistance in the field and greenhouse. The Pi34 locus is located in the 54.1-kb region on the genomic sequence of cv. Nipponbare. We constructed a bacterial artificial chromosome (BAC) library of Chubu 32, selected the clone containing Pi34, and sequenced it. The Pi34 locus consequently was located on an interval of 65.3 kb containing 10 predicted open reading frames (ORFs). Two of these ORFs were predicted only in Chubu 32 and encoded transposable elements. The other eight ORFs were found in both Chubu 32 and Nipponbare and one of them, which encoded an unknown protein, showed significantly different amino acid sequences between two cultivars. The new QTL, Piq6(t), was detected on the short arm of chromosome 6 and the genetic distance of flanking markers was 16.9 centimorgans in Nipponbare. Pi34 and Piq6(t) acted additively on resistance to rice blast but the effect of Piq6(t) was relatively small compared with Pi34.

20.
Nat Biotechnol ; 16(9): 847-50, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9743118

RESUMEN

A large-scale production system of uridine 5'-diphospho-galactose (UDP-Gal) has been established by the combination of recombinant Escherichia coli and Corynebacterium ammoniagenes. Recombinant E. coli that overexpress the UDP-Gal biosynthetic genes galT, galK, and galU were generated. C. ammoniagenes contribute the production of uridine triphosphate (UTP), a substrate for UDP-Gal biosynthesis, from orotic acid, an inexpensive precursor of UTP. UDP-Gal accumulated to 72 mM (44 g/L) after a 21 h reaction starting with orotic acid and galactose. When E. coli cells that expressed the alpha1,4-galactosyltransferase gene of Neisseria gonorrhoeae were coupled with this UDP-Gal production system, 372 mM (188 g/L) globotriose (Galalpha1-4Galbeta1-4Glc), a trisaccharide portion of verotoxin receptor, was produced after a 36 h reaction starting with orotic acid, galactose, and lactose. No oligosaccharide by-products were observed in the reaction mixture. The production of globotriose was several times higher than that of UDP-Gal. The strategy of producing sugar nucleotides by combining metabolically engineered recombinant E. coli with a nucleoside 5'-triphosphate producing microorganism, and the concept of producing oligosaccharides by coupling sugar nucleotide production systems with glycosyltransferases, can be applied to the manufacture of other sugar nucleotides and oligosaccharides.


Asunto(s)
Escherichia coli/genética , Trisacáridos/biosíntesis , Uridina Difosfato Galactosa/biosíntesis , Secuencia de Bases , Conformación de Carbohidratos , Secuencia de Carbohidratos , Clonación Molecular , Corynebacterium/genética , Cartilla de ADN , Datos de Secuencia Molecular , Neisseria gonorrhoeae/genética , Plásmidos , Recombinación Genética , Trisacáridos/química
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