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1.
Braz. j. med. biol. res ; 48(5): 479-485, 05/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-744381

RESUMEN

Neoadjuvant chemotherapy has practical and theoretical advantages over adjuvant chemotherapy strategy in breast cancer (BC) management. Moreover, metronomic delivery has a more favorable toxicity profile. The present study examined the feasibility of neoadjuvant metronomic chemotherapy in two cohorts [HER2+ (TraQme) and HER2− (TAME)] of locally advanced BC. Twenty patients were prospectively enrolled (TraQme, n=9; TAME, n=11). Both cohorts received weekly paclitaxel at 100 mg/m2 during 8 weeks followed by weekly doxorubicin at 24 mg/m2 for 9 weeks in combination with oral cyclophosphamide at 100 mg/day (fixed dose). The HER2+ cohort received weekly trastuzumab. The study was interrupted because of safety issues. Thirty-six percent of patients in the TAME cohort and all patients from the TraQme cohort had stage III BC. Of note, 33% from the TraQme cohort and 66% from the TAME cohort displayed hormone receptor positivity in tumor tissue. The pathological complete response rates were 55% and 18% among patients enrolled in the TraQme and TAME cohorts, respectively. Patients in the TraQme cohort had more advanced BC stages at diagnosis, higher-grade pathological classification, and more tumors lacking hormone receptor expression, compared to the TAME cohort. The toxicity profile was also different. Two patients in the TraQme cohort developed pneumonitis, and in the TAME cohort we observed more hematological toxicity and hand-foot syndrome. The neoadjuvant metronomic chemotherapy regimen evaluated in this trial was highly effective in achieving a tumor response, especially in the HER2+ cohort. Pneumonitis was a serious, unexpected adverse event observed in this group. Further larger and randomized trials are warranted to evaluate the association between metronomic chemotherapy and trastuzumab treatment.


Asunto(s)
Humanos , Descontaminación/métodos , Geobacillus stearothermophilus/efectos de los fármacos , Peróxido de Hidrógeno/administración & dosificación , Control de Infecciones/métodos
2.
Braz J Med Biol Res ; 48(5): 479-85, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25760024

RESUMEN

Neoadjuvant chemotherapy has practical and theoretical advantages over adjuvant chemotherapy strategy in breast cancer (BC) management. Moreover, metronomic delivery has a more favorable toxicity profile. The present study examined the feasibility of neoadjuvant metronomic chemotherapy in two cohorts [HER2+ (TraQme) and HER2- (TAME)] of locally advanced BC. Twenty patients were prospectively enrolled (TraQme, n=9; TAME, n=11). Both cohorts received weekly paclitaxel at 100 mg/m(2) during 8 weeks followed by weekly doxorubicin at 24 mg/m(2) for 9 weeks in combination with oral cyclophosphamide at 100 mg/day (fixed dose). The HER2+ cohort received weekly trastuzumab. The study was interrupted because of safety issues. Thirty-six percent of patients in the TAME cohort and all patients from the TraQme cohort had stage III BC. Of note, 33% from the TraQme cohort and 66% from the TAME cohort displayed hormone receptor positivity in tumor tissue. The pathological complete response rates were 55% and 18% among patients enrolled in the TraQme and TAME cohorts, respectively. Patients in the TraQme cohort had more advanced BC stages at diagnosis, higher-grade pathological classification, and more tumors lacking hormone receptor expression, compared to the TAME cohort. The toxicity profile was also different. Two patients in the TraQme cohort developed pneumonitis, and in the TAME cohort we observed more hematological toxicity and hand-foot syndrome. The neoadjuvant metronomic chemotherapy regimen evaluated in this trial was highly effective in achieving a tumor response, especially in the HER2+ cohort. Pneumonitis was a serious, unexpected adverse event observed in this group. Further larger and randomized trials are warranted to evaluate the association between metronomic chemotherapy and trastuzumab treatment.


Asunto(s)
Administración Metronómica , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/tratamiento farmacológico , Terapia Neoadyuvante , Receptor ErbB-2 , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/patología , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Síndrome Mano-Pie/etiología , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Terapia Neoadyuvante/efectos adversos , Clasificación del Tumor , Paclitaxel/administración & dosificación , Neumonía/etiología , Estudios Prospectivos , Receptores de Estrógenos/análisis , Trastuzumab
3.
Mycoses ; 48(1): 38-41, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15679664

RESUMEN

We reassessed the in vitro synergistic effect of fluconazole with the non-steroidal anti-inflammatory agent ibuprofen against the pathogenic yeast Candida albicans. No synergistic effect of fluconazole combined with ibuprofen was seen against fluconazole-susceptible strains, but a remarkable effect was seen against fluconazole-resistant strains (FIX index: 0.02-0.03). Furthermore, vigorous growth of the microorganism, the so-called 'Eagle effect', was observed at concentrations higher than the minimal inhibitory concentrations of ibuprofen and fluconazole. Our results suggest that the combination of ibuprofen and fluconazole should prove useful for treating infection caused by fluconazole-resistant C. albicans.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Fluconazol/farmacología , Ibuprofeno/farmacología , Farmacorresistencia Fúngica , Sinergismo Farmacológico , Humanos , Pruebas de Sensibilidad Microbiana/métodos
4.
Histochem Cell Biol ; 121(3): 181-8, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14986002

RESUMEN

We used immunohistochemistry to identify the localization of monoamine oxidase type B (MAOB) in the rat oxyntic mucosa. At light microscopic levels, MAOB-immunopositive cells were mostly located in the basal half of the oxyntic mucosa. By a double-labeling immunofluorescence method, it was shown that MAOB immunoreactivity was localized in almost all of histidine decarboxylase (HDC)-positive cells. Only a few MAOB-positive cells were negative for HDC. At electron microscopic levels, immunohistochemical reaction products of MAOB were detected on the mitochondrial outer membranes in cells that showed morphological characteristics of enterochromaffin-like (ECL) cells. These findings indicate that ECL cells contain MAOB in the rat. We provide a hypothesis that MAOB is involved in the inactivation mechanism of histamine that is released from ECL cells and activates parietal cells to secrete gastric acid.


Asunto(s)
Células Similares a las Enterocromafines/enzimología , Mucosa Gástrica/enzimología , Histidina Descarboxilasa/metabolismo , Mitocondrias/metabolismo , Monoaminooxidasa/metabolismo , Animales , Masculino , Microscopía Electrónica , Conejos , Ratas , Ratas Sprague-Dawley
5.
Adv Space Res ; 31(7): 1833-7, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14503524

RESUMEN

In order to control the material circulation in the Closed Ecology Experiment Facilities (CEEF), it is necessary to clarify material flow in the Closed Plant Experiment Facility (CPEF) of CEEF. We tried to grow rice plants and measure the nitrogen contents in rice plant and nutrient solution in plant cultivation bed to trace the material balance in CPEF. The measurements were carried out under the condition of 750 ppm (v/v) CO2 at 26/19 degrees C in the plant cultivation room. The measurements showed the absorbed nitrogen amount in plant was less than the outflow nitrogen amount from nutrient solution. This difference between absorbed and outflow quantity reached to 17%.


Asunto(s)
Sistemas Ecológicos Cerrados , Sistemas de Manutención de la Vida , Nitrógeno/análisis , Oryza/metabolismo , Amoníaco/síntesis química , Biomasa , Medios de Cultivo/química , Arquitectura y Construcción de Instituciones de Salud , Fertilizantes , Luna , Nitratos/síntesis química , Nitrógeno/química , Nitrógeno/metabolismo , Oryza/química , Oryza/crecimiento & desarrollo
6.
Genetica ; 119(1): 99-106, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12903752

RESUMEN

The Japanese rose bitterling, Rhodeus ocellatus kurumeus, and the oily bitterling, Tanakia limbata, were cytogenetically studied by silver (Ag)- and chromomycin A3 (CMA3)-staining, by C-banding and by mapping of the 18S ribosomal genes and of the (TTAGGG)n telomeric sequence. These two representative species of related genera of the subfamily Acheilognathinae show very similar chromosome complements. Nevertheless, significant differences in the chromosomal distribution of nucleolus organizer regions (NORs) and interstitial telomeric sequences were observed. Whereas R. ocellatus kurumeus shows a single NOR-bearing chromosome pair, T. limbata is characterized by a higher number of variable NORs. Multiple telomeric sequence sites were found at the pericentromeric regions of several chromosomes in the rose bitterling. No telomeric sequence sites were detected near centromeres, but they were found to be scattered along the NORs in the oily bitterling. Two karyoevolutive trends might have been identified in the subfamily.


Asunto(s)
Cyprinidae/genética , ARN Ribosómico 18S/genética , Telómero/genética , Animales , Cromomicina A3 , Bandeo Cromosómico , Mapeo Cromosómico , Hibridación Fluorescente in Situ , Japón , Cariotipificación , Tinción con Nitrato de Plata
7.
Neuroscience ; 114(4): 825-35, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12379239

RESUMEN

Monoamine oxidase type A and type B are major neurotransmitter-degrading enzymes in the CNS. The type A is present on mitochondrial outer membranes in the whole extent of noradrenergic and dopaminergic neurons, including their axon terminals. The type B is present in serotonergic neurons, but its subcellular localization has not been elucidated. In the present study, we used both a double-labeling immunofluorescence method and electron microscopic immunohistochemistry to examine the subcellular localization of monoamine oxidase type B in serotonergic neurons projecting from the dorsal raphe nucleus to the suprachiasmatic nucleus in the rat brain. In the dorsal raphe nucleus, serotonin-positive neuronal cell bodies were clustered, and virtually all of these cell bodies were also positive for monoamine oxidase type B. By contrast, serotonin-negative neuronal cell bodies were mostly free of this enzyme. Within the neuronal cell bodies and dendrites that were positive for monoamine oxidase type B, most mitochondria contained this enzyme on their outer membranes, but a substantial proportion of mitochondria lacked this enzyme. In the suprachiasmatic nucleus, serotonin-positive varicosities were concentrated, but none of these varicosities exhibited monoamine oxidase type B. In this nucleus, mitochondria were found in almost all serotonin-positive axon terminals, but monoamine oxidase type B was not observed in any axon terminal that contained mitochondria. Our results show that there are two kinds of mitochondria in serotonergic neuronal cell bodies and dendrites: one containing monoamine oxidase type B on their outer membranes, and the other lacking this enzyme. In addition, mitochondria in serotonergic axon terminals do not possess monoamine oxidase type B. It is suggested in serotonergic neurons that only mitochondria lacking monoamine oxidase type B are transported by axonal flow up to axon terminals. It is also probable that mitochondria containing monoamine oxidase type B are transported along the axons, but that this enzyme undergoes a change, for example, conformational change, decomposition or removal from the membranes.


Asunto(s)
Mitocondrias/enzimología , Monoaminooxidasa/análisis , Neuronas/enzimología , Serotonina/fisiología , Animales , Transporte Axonal/fisiología , Técnicas para Inmunoenzimas , Masculino , Microscopía Confocal , Microscopía Electrónica , Monoaminooxidasa/metabolismo , Neuronas/ultraestructura , Núcleos del Rafe/citología , Ratas , Ratas Sprague-Dawley , Núcleo Supraquiasmático/citología
8.
J Neural Transm (Vienna) ; 109(5-6): 683-9, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12111460

RESUMEN

This study reports the presence of noradrenergic (NA) neurons which are capable to take up 5-hydroxytryptophan (5-HTP) and decarboxylate it to 5-hydroxytryptamine (5-HT serotonin) in the kitten brain. After loading of 5-HTP and monoamine oxidase inhibitor (MAOI), we could demonstrate 5-HT-immunoreactivity (IR) not only in hypothalamic and midbrain dopaminergic (DA) cell bodies, but also in NA ones located in the pons and medulla oblongata of the new born kitten aged from 1 to 7 days. NA cell bodies could no longer show 5-HT-IR after this treatment in the kitten older than 1 month. On the other hand, 5-HT-IR in the ventrolateral posterior hypothalamic (VLPH) cells was very weak at birth and became more and more intense after 15 days of age. Finally, after loading of tryptophan (TP) and MAOI, 5-HTP uptake cells mentioned above did not express 5-HT-IR in the kitten brain.


Asunto(s)
5-Hidroxitriptófano/metabolismo , 5-Hidroxitriptófano/farmacocinética , Animales Recién Nacidos/metabolismo , Encéfalo/metabolismo , Envejecimiento/metabolismo , Animales , Gatos , Descarboxilación , Combinación de Medicamentos , Femenino , Masculino , Inhibidores de la Monoaminooxidasa/farmacología , Pargilina/farmacología , Serotonina/metabolismo , Cloruro de Sodio/farmacología , Distribución Tisular , Triptófano/farmacología
9.
Biochem Biophys Res Commun ; 289(1): 299-304, 2001 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-11708816

RESUMEN

We have generated a novel model protein for an artificial light-harvesting complex composed of two proteins, cytochrome b(562) (cytb(562)) and enhanced green fluorescent protein (EGFP), in which two chromophores are fixed in each protein matrix. Cytb(562) was appended to the N-terminus of EGFP via a Gly-Ser linker and the resultant fusion protein was successfully expressed in Escherichia coli as a mixture of the apo- and the holo-forms as to the cytb(562) moiety. The fluorescence of EGFP was substantially quenched when the apo-form was reconstituted with hemin. Based on the fluorescence lifetime measurements, it appeared that light energy entrapped by EGFP is transferred to the heme of cytb(562) by resonance energy transfer (energy transfer yield: 65%). Spatial organization of two chromophores using small and stable protein matrices will be promising toward the construction of an artificial light-harvesting complex by protein engineering.


Asunto(s)
Grupo Citocromo b/química , Proteínas de Escherichia coli , Proteínas Luminiscentes/genética , Grupo Citocromo b/genética , Diseño de Fármacos , Escherichia coli/genética , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/química , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Proteínas del Complejo del Centro de Reacción Fotosintética/genética , Ingeniería de Proteínas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Espectrometría de Fluorescencia , Espectrofotometría
10.
Adv Space Res ; 27(9): 1541-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11695434

RESUMEN

In order to predict carbon sequestration of vegetation with the future rise in atmospheric CO2 concentration, [CO2] and temperature, long term effects of high [CO2] and high temperature on responses of both photosynthesis and transpiration of plants as a whole community to environmental parameters need to be elucidated. Especially in the last decade, many studies on photosynthetic acclimation to elevated [CO2] at gene, cell, tissue or leaf level for only vegetative growth phase (i.e. before formation of reproductive organs) have been conducted all over the world. However, CO2 acclimation studies at population or community level for a whole growing season are thus far very rare. Data obtained from repeatable experiments at population or community level for a whole growing season are necessary for modeling carbon sequestration of a plant community. On the other hand, in order to stabilize material circulation in the artificial ecological system of Closed Ecology Experiment Facilities (CEEF), it is necessary to predict material exchange rates in the biological systems. In particular, the material exchange rate in higher plant systems is highly variable during growth periods and there is a strong dependence on environmental conditions. For this reason, dependencies of both CO2 exchange rate and transpiration rate of three rice populations grown from seed under differing conditions of [CO2] and day/night air temperature (350 microL CO2 L-1, 24/17 degrees C (population A); 700 microL CO2 L-1, 24/17 degrees C (population B) and 700 microL CO2 L-1, 26/19 degrees C (population C)) upon PPFD, leaf temperature and [CO2] were investigated every two weeks during whole growing season. Growth of leaf lamina, leaf sheath, panicle and root was also compared. From this experiment, it was elucidated that acclimation of instantaneous photosynthetic response of rice population to [CO2] occurs in vegetative phase through changes in ratio of leaf area to whole plant dry weight, LAR. But, in reproductive growth phase (i.e. after initiation of panicle formation), the difference between photosynthetic response to [CO2] of population A and that of population B decreased. Although LAR of population C was almost always less than that of population A, there was no difference between the photosynthetic response to [CO2] of population A at 24 degrees C and that of population C at 26 degrees C for its whole growth period. These results are useful to make a model to predict carbon sequestration of rice community, which is an important type of vegetation especially in Asia in future global environmental change.


Asunto(s)
Dióxido de Carbono/farmacología , Sistemas Ecológicos Cerrados , Oryza/crecimiento & desarrollo , Fotosíntesis/fisiología , Transpiración de Plantas/fisiología , Relación Dosis-Respuesta a Droga , Ambiente Controlado , Sistemas de Manutención de la Vida , Modelos Biológicos , Oryza/efectos de los fármacos , Fotones , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Fenómenos Fisiológicos de las Plantas , Temperatura
11.
Protein Eng ; 14(8): 529-32, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11579220

RESUMEN

With the aim of separating the domains of a bifunctional fusion protein, the ability of several lengths of helix-forming peptides to separate two weakly interacting beta-can domains was compared with that of flexible linkers or of a three alpha-helices bundle domain. We introduced helix-forming peptide linkers A(EAAAK)nA (n = 2-5) between two green fluorescent protein variants, EBFP and EGFP, and investigated their spectral properties. The fluorescence resonance energy transfer from EBFP to EGFP decreased as the length of the linkers increased. The circular dichroism spectra analysis suggested that the linkers form an alpha-helix and the alpha-helical contents increased as the length of the linkers increased. The results clearly suggested the ability of the helical linkers to control the distance and reduce the interference between the domains. This 'linker engineering' may open a way to the rational design of linkers which maximize the multiple functions of fusion proteins or de novo multi-domain proteins.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Diseño de Fármacos , Proteínas Recombinantes de Fusión/química , Dicroismo Circular , Transferencia de Energía , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/química , Modelos Moleculares , Péptidos/química , Péptidos/genética , Estructura Secundaria de Proteína , Proteínas Recombinantes de Fusión/genética , Espectrometría de Fluorescencia , Transformación Genética
12.
Kaibogaku Zasshi ; 76(4): 381-8, 2001 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-11577440

RESUMEN

The aim of the present study is to demonstrate the cellular basis of 5'-nucleotidase (5'-Nase) activity in the greater omentum of rats. Enzyme histochemistry for 5'-Nase showed that lymphatic vessels in the omentum as well as lymphocytes in the milky spots were positively stained. Electron microscopic observation revealed-5'-Nase activity at the luminal surface of the lymphatic endothelial cells, pinocytotic vesicles in the endothelial cells and the surface of fibroblasts located at the intercellular space of adipose cells. Fibroblasts extended long cytoplasmic processes toward adipose cells and inflammatory cells. These findings suggest that lymphatic endothelial cells as well as fibroblasts in the omentum may play an important role in regulation of metabolism and immune mechanisms in the greater omentum by supplying adenosin.


Asunto(s)
5'-Nucleotidasa/metabolismo , Epiplón/enzimología , Adenosina/metabolismo , Adenosina/fisiología , Animales , Sistema Linfático/enzimología , Sistema Linfático/inmunología , Linfocitos/enzimología , Linfocitos/inmunología , Masculino , Ratas , Ratas Wistar
13.
Mol Biol Cell ; 12(5): 1367-80, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11359928

RESUMEN

We characterized the novel Schizosaccharomyces pombe genes myo4(+) and myo5(+), both of which encode myosin-V heavy chains. Disruption of myo4 caused a defect in cell growth and led to an abnormal accumulation of secretory vesicles throughout the cytoplasm. The mutant cells were rounder than normal, although the sites for cell polarization were still established. Elongation of the cell ends and completion of septation required more time than in wild-type cells, indicating that Myo4 functions in polarized growth both at the cell ends and during septation. Consistent with this conclusion, Myo4 was localized around the growing cell ends, the medial F-actin ring, and the septum as a cluster of dot structures. In living cells, the dots of green fluorescent protein-tagged Myo4 moved rapidly around these regions. The localization and movement of Myo4 were dependent on both F-actin cables and its motor activity but seemed to be independent of microtubules. Moreover, the motor activity of Myo4 was essential for its function. These results suggest that Myo4 is involved in polarized cell growth by moving with a secretory vesicle along the F-actin cables around the sites for polarization. In contrast, the phenotype of myo5 null cells was indistinguishable from that of wild-type cells. This and other data suggest that Myo5 has a role distinct from that of Myo4.


Asunto(s)
Polaridad Celular , Proteínas Fúngicas/metabolismo , Cadenas Pesadas de Miosina , Miosina Tipo I , Miosina Tipo V , Miosinas/metabolismo , Transporte de Proteínas/fisiología , Proteínas de Saccharomyces cerevisiae , Schizosaccharomyces/genética , Vesículas Secretoras/metabolismo , Actinas/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , División Celular/fisiología , Colorantes Fluorescentes/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Genes Reporteros , Humanos , Cinética , Microscopía Fluorescente , Microtúbulos/metabolismo , Datos de Secuencia Molecular , Miosinas/química , Miosinas/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Schizosaccharomyces/fisiología , Schizosaccharomyces/ultraestructura
14.
J Clin Endocrinol Metab ; 86(4): 1795-800, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11297620

RESUMEN

We studied a 60-yr-old female with a brain tumor who showed severe symptoms of hypoglycemia (plasma glucose, 2.2 mmol/L) and hyperinsulinemia (1.28 nmol/L) after radiotherapy. The cystic brain tumor contained proinsulin and insulin at concentrations of 13.6 and 1.22 nmol/L, respectively. Immunohistochemical studies showed the tumor cells were ectodermal in origin but not endodermal, based on three diagnostic features of neuroectodermal tumors 1) pseudorosette formation noted under light microscopy, 2) finding of a small number of dense core neurosecretory granules on electron microscopy, and 3) positive immunostaining for both neuronal specific enolase and protein gene product 9.5. These cells also expressed the transcription factor, neurogenin-3, NeuroD/beta 2, and islet factor I, which are believed to be transcription factors in neuroectoderm as well as in pancreatic islet cells, but not pancreatic-duodenal homeobox 1, Pax4, or Nkx2.2. In addition, they did not express glucagon, somatostatin, or glucagon-like peptide-1. Our results show the presence of proinsulin in an ectoderm cell brain tumor that does not express the homeobox gene, pancreatic-duodenal homeobox 1, but expresses other transcription factors, i.e. neurogenin3, NeuroD/beta 2, and islet factor-1, which are related to insulin gene expression in the brain tumor.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Proteínas de Homeodominio/metabolismo , Insulina/biosíntesis , Tumores Neuroectodérmicos/metabolismo , Transactivadores/metabolismo , Antígenos de Diferenciación/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Encéfalo/metabolismo , Encéfalo/patología , Neoplasias Encefálicas/patología , Femenino , Proteína Homeobox Nkx-2.2 , Humanos , Proteínas con Homeodominio LIM , Persona de Mediana Edad , Proteínas del Tejido Nervioso/metabolismo , Tumores Neuroectodérmicos/patología , Proteínas Nucleares , Factores de Transcripción , Ubiquitina Tiolesterasa
15.
Anal Biochem ; 289(1): 77-81, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11161297

RESUMEN

We describe a noncompetitive homogeneous bioluminescent immunoassay based on the antigen-dependent reassociation of antibody variable domains (open sandwich bioluminescent immunoassay, OS-BLIA). The reassociation of two chimeric proteins, an antibody heavy-chain fragment (V(H))-Renilla luciferase (Rluc) and an antibody light-chain fragment (V(L))-enhanced yellow fluorescent protein (EYFP), was monitored by a bioluminescence resonance energy transfer (BRET) between the two. Upon simple mixing of the reagents with the sample, an antigen-dependent increase in BRET was observed with a measurable concentration range of 0.1 to approximately 10 microg/ml antigen hen egg lysozyme. Compared with our comparable assays based on fluorescence resonance energy transfer (FRET), a 10-fold improvement in the sensitivity was attained, probably due to a reduction in reagent concentration.


Asunto(s)
Inmunoensayo/métodos , Proteínas Bacterianas/química , Secuencia de Bases , Cartilla de ADN , Transferencia de Energía , Mediciones Luminiscentes , Proteínas Luminiscentes/química , Proteínas Recombinantes de Fusión/química
16.
J Biosci Bioeng ; 92(3): 301-4, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-16233101

RESUMEN

Green fluorescent protein (GFP) reporter genes for the bacterial umu-test were constructed. Utilization of tandem, lacUV5 and chimeric trp/umu promoters, and coexpression of the Escherichia coli recA5327 mutant enhanced the GFP expression level fourteen-fold over that of the system with only the umu promoter, thereby improving the sensitivity of the umu-test.

17.
Genetica ; 111(1-3): 423-32, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11841185

RESUMEN

In bitterlings (Acheilognathinae) C- and Ag-banding karyotypes of 6 species-subspecies collected in China and South Korea were analyzed. The chromosomal constitution of 2n =46 (4 SM + 42 ST) in Rhodeus atremius fangi was quite different from that of 2n = 48 (8 M + 20 SM + 20 ST) in other species-subspecies in Rhodeus. It was concluded from the analysis of banded chromosomes that the increase in number of ST during the karyotype change from 2n = 48 to 2n = 46 was achieved by a series of pericentric inversions from 24 M-SM to 24 ST, and the decrease in the diploid number was caused by an additional tandem fusion of 4 ST chromosomes, forming a new ST pair in the 2n = 46 karyotype. The karyotype of Tanakia koreensis, T. signifer, and Acheilognathus macropterus is 2n = 48 (8 M + 20 SM + 20 ST), 2n = 48 (8 M + 20 SM + 14-16 ST + 4-6 A), 2n = 44 (14M + 16 SM + 14 ST), respectively. In R. ocellatus ocellatus, T. koreensis, T. signifer and A. macropterus, karyotype changes from 2n = 48 to 2n = 44 due to centric fusion and inversion have also been estimated. It was suggested that C-banding heterochromatin was greatly concerned with the karyotype evolution in bitterlings.


Asunto(s)
Evolución Biológica , Cyprinidae/genética , Cariotipificación , Animales , Especificidad de la Especie
18.
Cell Struct Funct ; 26(6): 545-54, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11942608

RESUMEN

How actin filaments (F-actin) and myosin II (myosin) assemble to form the contractile ring was investigated with fission yeast and Xenopus egg. In fission yeast cells, an aster-like structure composed of F-actin cables is formed at the medial cortex of the cell during prophase to metaphase, and a single F-actin cable(s) extends from this structure, which seems to be a structural basis of the contractile ring. In early mitosis, myosin localizes as dots in the medial cortex independently of F-actin. Then they fuse with each other and are packed into a thin contractile ring. At the growing ends of the cleavage furrow of Xenopus eggs, F-actin at first assembles to form patches. Next they fuse with each other to form short F-actin bundles. The short bundles then form long bundles. Myosin seems to be transported by the cortical movement to the growing end and assembles there as spots earlier than F-actin. Actin polymerization into the patches is likely to occur after accumulation of myosin. The myosin spots and the F-actin patches are simultaneously reorganized to form the contractile ring bundles. The idea that a Ca signal triggers cleavage furrow formation was tested with Xenopus eggs during the first cleavage. We could not detect any Ca signals such as a Ca wave, Ca puffs or even Ca blips at the growing end of the cleavage furrow. Furthermore, cleavages are not affected by Ca-chelators injected into the eggs at concentrations sufficient to suppress the Ca waves. Thus we conclude that formation of the contractile ring is not induced by a Ca signal at the growing end of the cleavage furrow.


Asunto(s)
Actinas/metabolismo , División Celular/fisiología , Miosina Tipo II/metabolismo , Oocitos/citología , Schizosaccharomyces/fisiología , Xenopus laevis/fisiología , Animales , Calcio/metabolismo , Citoesqueleto/metabolismo , Oocitos/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Xenopus/metabolismo
19.
Mol Biol Cell ; 11(12): 4393-401, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11102532

RESUMEN

Schizosaccharomyces pombe rho1(+) and rho2(+) genes are involved in the control of cell morphogenesis, cell integrity, and polarization of the actin cytoskeleton. Although both GTPases interact with each of the two S. pombe protein kinase C homologues, Pck1p and Pck2p, their functions are distinct from each other. It is known that Rho1p regulates (1,3)beta-D-glucan synthesis both directly and through Pck2p. In this paper, we have investigated Rho2p signaling and show that pck2 delta and rho2 delta strains display similar defects with regard to cell wall integrity, indicating that they might be in the same signaling pathway. We also show that Rho2 GTPase regulates the synthesis of alpha-D-glucan, the other main structural polymer of the S. pombe cell wall, primarily through Pck2p. Although overexpression of rho2(+) in wild-type or pck1 delta cells is lethal and causes morphological alterations, actin depolarization, and an increase in alpha-D-glucan biosynthesis, all of these effects are suppressed in a pck2 delta strain. In addition, genetic interactions suggest that Rho2p and Pck2p are important for the regulation of Mok1p, the major (1-3)alpha-D-glucan synthase. Thus, a rho2 delta mutation, like pck2 delta, is synthetically lethal with mok1-664, and the mutant partially fails to localize Mok1p to the growing areas. Moreover, overexpression of mok1(+) in rho2 delta cells causes a lethal phenotype that is completely different from that of mok1(+) overexpression in wild-type cells, and the increase in alpha-glucan is considerably lower. Taken together, all of these results indicate the presence of a signaling pathway regulating alpha-glucan biosynthesis in which the Rho2p GTPase activates Pck2p, and this kinase in turn controls Mok1p.


Asunto(s)
Pared Celular/metabolismo , Proteínas Fúngicas/fisiología , Glucanos/metabolismo , Proteína Quinasa C/fisiología , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/metabolismo , Proteínas de Unión al GTP rho/fisiología , Celulasa/metabolismo , Proteínas Fúngicas/genética , Eliminación de Gen , Proteína Quinasa C/genética , Schizosaccharomyces/ultraestructura , Proteínas de Unión al GTP rho/genética
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