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1.
Nature ; 632(8025): 513-516, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38914113

RESUMEN

The Cosmic Gems arc is among the brightest and highly magnified galaxies observed at redshift z ≈ 10.2 (ref. 1). However, it is an intrinsically ultraviolet faint galaxy, in the range of those now thought to drive the reionization of the Universe2-4. Hitherto the smallest features resolved in a galaxy at a comparable redshift are between a few hundreds and a few tens of parsecs (pc)5,6. Here we report JWST observations of the Cosmic Gems. The light of the galaxy is resolved into five star clusters located in a region smaller than 70 pc. They exhibit minimal dust attenuation and low metallicity, ages younger than 50 Myr and intrinsic masses of about 106M⊙. Their lensing-corrected sizes are approximately 1 pc, resulting in stellar surface densities near 105M⊙ pc-2, three orders of magnitude higher than typical young star clusters in the local Universe7. Despite the uncertainties inherent to the lensing model, they are consistent with being gravitationally bound stellar systems, that is, proto-globular clusters. We conclude that star cluster formation and feedback likely contributed to shaping the properties of galaxies during the epoch of reionization.

2.
Nature ; 557(7705): 392-395, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29769675

RESUMEN

A fundamental quest of modern astronomy is to locate the earliest galaxies and study how they influenced the intergalactic medium a few hundred million years after the Big Bang1-3. The abundance of star-forming galaxies is known to decline4,5 from redshifts of about 6 to 10, but a key question is the extent of star formation at even earlier times, corresponding to the period when the first galaxies might have emerged. Here we report spectroscopic observations of MACS1149-JD1 6 , a gravitationally lensed galaxy observed when the Universe was less than four per cent of its present age. We detect an emission line of doubly ionized oxygen at a redshift of 9.1096 ± 0.0006, with an uncertainty of one standard deviation. This precisely determined redshift indicates that the red rest-frame optical colour arises from a dominant stellar component that formed about 250 million years after the Big Bang, corresponding to a redshift of about 15. Our results indicate that it may be possible to detect such early episodes of star formation in similar galaxies with future telescopes.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39169473

RESUMEN

Amyloid fibril formation is associated with various amyloidoses, including neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Despite the numerous studies on the inhibition of amyloid formation, the prevention and treatment of a majority of amyloid-related disorders are still challenging. In this study, we investigated the effects of various plant extracts on amyloid formation of α-synuclein. We found that the extracts from Eucalyptus gunnii are able to inhibit amyloid formation, and to disaggregate preformed fibrils, in vitro. The extract itself did not lead cell damage. In the extract, miquelianin, which is a glycosylated form of quercetin and has been detected in the plasma and the brain, was identified and assessed to have a moderate inhibitory activity, compared to the effects of ellagic acid and quercetin, which are strong inhibitors for amyloid formation. The properties of miquelianin provide insights into the mechanisms controlling the assembly of α-synuclein in the brain.

4.
J Oral Maxillofac Surg ; 75(9): 1891-1898, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28390760

RESUMEN

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare genetic condition characterized by congenital malformation and progressive heterotopic ossification (HO) caused by a recurrent single nucleotide substitution at position 617 in the ACVR1 gene. As the condition progresses, HO leads to joint ankylosis, breathing difficulties, and mouth-opening restriction, and it can shorten the patient's lifespan. This report describes 3 cases of FOP confirmed by genetic testing in patients with restricted mouth opening. Each patient presented a different onset and degree of jaw movement restriction. The anatomic ossification site of the mandibular joint was examined in each patient using reconstructed computed tomographic (CT) images and 3-dimensional reconstructed CT (3D-CT) images. A 29-year-old woman complained of jaw movement restriction since 13 years of age. 3D-CT image of the mandibular joint showed an osseous bridge, formed by the mandibular depressors that open the mouth, between the hyoid bone and the mentum of the mandible. A 39-year-old man presented with jaw movement restriction that developed at 3 years of age after a mouth injury. 3D-CT image of the jaw showed ankylosis of the jaw from ossification of the mandibular depressors that was worse than in patient 1. CT images showed no HO findings of the masticatory muscles. To the authors' knowledge, these are the first 2 case descriptions of the anatomic site of ankylosis involving HO of the mandibular depressors in the jaw resulting from FOP. In contrast, a 62-year-old bedridden woman with an interincisal distance longer than 10 mm (onset, 39 years of age) had no HO of the mandibular depressors and slight HO of the medial pterygoid muscle on the right and left sides. These findings suggest that restricted mouth opening varies according to the presence or absence of HO of the mandibular depressors.


Asunto(s)
Enfermedades Mandibulares/fisiopatología , Miositis Osificante/fisiopatología , Músculos Pterigoideos/fisiopatología , Trismo/fisiopatología , Adulto , Progresión de la Enfermedad , Femenino , Humanos , Imagenología Tridimensional , Masculino , Enfermedades Mandibulares/diagnóstico por imagen , Persona de Mediana Edad , Miositis Osificante/diagnóstico por imagen , Músculos Pterigoideos/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Trismo/diagnóstico por imagen
5.
Biochem Biophys Res Commun ; 443(3): 911-6, 2014 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-24361895

RESUMEN

In kinesin X-ray crystal structures, the N-terminal region of the α-1 helix is adjacent to the adenine ring of the bound nucleotide, while the C-terminal region of the helix is near the neck-linker (NL). Here, we monitor the displacement of the α-1 helix within a kinesin monomer bound to microtubules (MTs) in the presence or absence of nucleotides using site-directed spin labeling EPR. Kinesin was doubly spin-labeled at the α-1 and α-2 helices, and the resulting EPR spectrum showed dipolar broadening. The inter-helix distance distribution showed that 20% of the spins have a peak characteristic of 1.4-1.7 nm separation, which is similar to what is predicted from the X-ray crystal structure, albeit 80% were beyond the sensitivity limit (>2.5 nm) of the method. Upon MT binding, the fraction of kinesin exhibiting an inter-helix distance of 1.4-1.7 nm in the presence of AMPPNP (a non-hydrolysable ATP analog) and ADP was 20% and 25%, respectively. In the absence of nucleotide, this fraction increased to 40-50%. These nucleotide-induced changes in the fraction of kinesin undergoing displacement of the α-1 helix were found to be related to the fraction in which the NL undocked from the motor core. It is therefore suggested that a shift in the α-1 helix conformational equilibrium occurs upon nucleotide binding and release, and this shift controls NL docking onto the motor core.


Asunto(s)
Cinesinas/química , Cinesinas/metabolismo , Nucleótidos/metabolismo , Marcadores de Spin , Adenosina Trifosfatasas/metabolismo , Cristalografía por Rayos X , Espectroscopía de Resonancia por Spin del Electrón , Microtúbulos/metabolismo , Mutagénesis Sitio-Dirigida , Proteínas Mutantes/química , Estructura Secundaria de Proteína , Rotación
6.
Environ Toxicol Chem ; 27(6): 1416-25, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18260696

RESUMEN

Phthalates are used industrially as plasticizers and are known to contaminate natural environments, mostly as di-ester or mono-ester complexes. Because they are structurally similar to natural estrogens, they could act as endocrine disruptors. Here, we used a DNA microarray containing estrogen responsive genes (EstrArray) to examine gene expression profiles in MCF-7 cells treated with 10 microM butylbenzyl phthalate (BBP), dibutyl phthalate (DBP), diethyl phthalate (DEP), and diisopropyl phthalate (DIP) along with the natural estrogen 17beta-estradiol ([E(2)], 10 nM). The profiles for phthalate esters and E(2) were examined by correlation analysis using correlation coefficients (r-values) and cluster analysis. We found that BBP showed the highest correlation with E(2) (r = 0.85), and DEP and DIP showed moderate r-values (r = 0.52 and r = 0.49, respectively). Dibutyl phthalate exhibited the lowest (but still significant) correlation with E(2) (r = 0.36). Furthermore, among the pairs of chemicals, DEP-DIP and DIP-DBP showed very high correlations (r = 0.90 and r = 0.80, respectively), and the other pairs showed moderate relationships, which reflected how structurally close they are to each other. The analysis of six functional groups of genes (enzymes, signaling, proliferation, transcription, transport, and others) indicated that the genes belonging to the enzyme, transcription, and other functional groups showed common responses to phthalate esters and E(2). Although the effect of BBP was similar to that of E(2), the other phthalate esters showed different types of effects. These results indicate that the structure of estrogenic chemicals is strongly related to their estrogenic activity and can be evaluated by appropriate grouping of the responsive genes by focused microarray analysis.


Asunto(s)
Disruptores Endocrinos/farmacología , Ésteres/farmacología , Estrógenos/farmacología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos , Ácidos Ftálicos/química , Línea Celular Tumoral , Ésteres/química , Humanos , Estructura Molecular , Especificidad por Sustrato
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 3028-3031, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30441033

RESUMEN

Upper-limb rehabilitation training for hemiplegic patients has been primarily conducted by human therapists, and, hence, their use of training methods and conditions strongly depends on their expertise. The force control and motion sensing functions of rehabilitation robots are expected to be used for the qualitative training/assessment in the next-generation computerized rehabilitation. In this study, we developed a desktop rehabilitation robot for upper limbs (D-SEMUL). In addition, we also assessed the usability of its user interface and the affinity (acceptance) of the training program with a questionnaire for elderly hemiplegic/non-hemiplegic participants (nine hemiplegic, five males and four females and seven non-hemiplegic, two males and five females). The results indicated that the touchscreen is acceptable for the user interface, and the background music used significantly affects the affinity of the program.


Asunto(s)
Música , Robótica , Extremidad Superior , Terapia por Ejercicio , Femenino , Humanos , Masculino
8.
Endocr Relat Cancer ; 14(2): 279-92, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17639044

RESUMEN

Early growth responsive gene 3 (EGR3) is a zinc-finger transcription factor and plays important roles in cellular growth and differentiation. We recently demonstrated estrogen-mediated induction of EGR3 in breast carcinoma cells. However, EGR3 has not yet been examined in breast carcinoma tissues and its significance remains unknown. Therefore, in this study, we examined biological functions of EGR3 in the breast carcinoma by immunohistochemistry, in vitro study, and nude mouse xenograft model. EGR3 immunoreactivity was detected in carcinoma cells in 99 (52%) out of 190 breast carcinoma tissues and was associated with the mRNA level. EGR3 immunoreactivity was positively associated with lymph node status, distant metastasis into other organs, estrogen receptor alpha, or EGR3 immunoreactivity in asynchronous recurrent lesions in the same patients, and was negatively correlated with tubule formation. EGR3 immunoreactivity was significantly associated with an increased risk of recurrence and adverse clinical outcome by both uni- and multivariate analyses. Egr3-expressing transformant cell lines derived from MCF-7 Tet-Off cells (Eg-10 and Eg-11) significantly enhanced the migration and invasion properties according to the treatment of doxycyclin, but did not significantly change the cell proliferation. Moreover, Eg-11 cells injected into athymic mice irregularly invaded into the adjacent peritumoral tissues, although Clt-7, which was stably transfected with empty vector as a control, demonstrated a well-circumscribed tumor. Eg-11 cells were significantly associated with invasive components and less tubule formation in the xenograft model. These results suggest that EGR3 plays an important role in estrogen-meditated invasion and is an independent prognostic factor in breast carcinoma.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Proteína 3 de la Respuesta de Crecimiento Precoz/análisis , Adulto , Anciano , Anciano de 80 o más Años , Animales , Neoplasias de la Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Células Cultivadas , Proteína 3 de la Respuesta de Crecimiento Precoz/genética , Estrógenos/metabolismo , Femenino , Humanos , Ratones , Ratones Desnudos , Persona de Mediana Edad , Invasividad Neoplásica , Trasplante de Neoplasias , Pronóstico , ARN Mensajero/análisis , Trasplante Heterólogo
9.
Toxicol In Vitro ; 21(4): 741-52, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17369015

RESUMEN

It is important to know the difference as well as the similarity in estrogen responsiveness among cell lines for understanding the effects of estrogenic chemicals. Here, using 120 estrogen responsive genes, we examined comparative expression profiles between the profile in breast cancer MCF-7 cells treated with 17beta-estradiol and the profiles in other cell lines derived from breast (T-47D and HBC-4 cells), endometrium (Ishikawa cells) and kidney (RXF-631L cells) treated with estrogenic chemicals. First, comparative profiling between MCF-7 and T-47D cells showed similar (correlation coefficient or R value=0.49-0.87) profiles for all chemicals examined: 17beta-estradiol, estrone, estriol, diethylstilbestrol, bisphenol A, nonylphenol and genistein. The analysis using other cell lines indicated that significant correlations to the profile in MCF-7 cells treated with 17beta-estradiol were observed for the profiles in Ishikawa cells treated with 17beta-estradiol, diethylstilbestrol and bisphenol A, and HBC-4 cells treated with 17beta-estradiol. The profiles for diethylstilbestrol and bisphenol A in HBC-4 cells and all three chemicals in RXF-631L cells did not show significant correlation with those in MCF-7 cells. Hierarchical cluster analysis revealed that there are cell-specific responses to estrogenic chemicals (T-47D and HBC-4 cells for example). Correlation analysis using six (proliferation, transcription, transport, enzymes, signaling and others) functionally-categorized gene groups indicated that the genes related to enzymes showed greater correlations for all chemicals tested in T-47D cells and some chemicals in Ishikawa and HBC-4 cells while those related to transcription contributed to variations.


Asunto(s)
Estrógenos no Esteroides/farmacología , Perfilación de la Expresión Génica , Transporte Biológico Activo/efectos de los fármacos , Transporte Biológico Activo/genética , Línea Celular , Proliferación Celular/efectos de los fármacos , ADN Complementario/biosíntesis , ADN Complementario/genética , Interpretación Estadística de Datos , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Transducción de Señal/efectos de los fármacos
10.
Food Chem Toxicol ; 45(12): 2470-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17664038

RESUMEN

Glycyrrhiza glabra root is one of the common traditional Chinese medicines and used as flavoring and sweetening agents for tobaccos, chewing gums, candies, toothpaste and beverages. While glycyrrhizin is one of the main components in the extract of G. glabra root and has been characterized, the other components have not been well characterized. The mechanism of growth activation of breast cancer MCF-7 cells, including the activation of Erk1/2 and Akt, and the transcriptional regulation of estrogen-responsive genes, was examined by means of sulforhodamine B, luciferase reporter gene, real-time RT-PCR and Western blotting assays after the induction of the cells with the extract of G. glabra root. The extract has similar activity to that induced by 17beta-estradiol (E(2)), although glycyrrhizin did not show such an activity. Moreover, the estrogen receptor alpha-dependent neurite outgrowth induced by the extract was similar to that by E(2), whereas glycyrrhizin had no effect. Furthermore, the expression profile examined by cDNA microarray assay using a set of 120 estrogen-responsive genes, which were related to proliferation, transcription, transport, enzymes and signaling, showed a statistically significant correlation (R=0.47, P<0.0001) between the profiles for E(2) and the extract. However, the expression profile for glycyrrhizin was different from that of the extract and E(2). The results indicate that rapid signaling pathways, including Erk1/2 and Akt, and the subsequent transcriptional regulation are involved in the proliferation of MCF-7 cells induced by the extract of G. glabra root. Furthermore, the extract had estrogenic activity and a distinguishable profile of gene expression, suggesting the presence of potentially useful components other than glycyrrhizin in G. glabra root for hormone and anti-cancer therapies.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Proliferación Celular/efectos de los fármacos , Glycyrrhiza , Ácido Glicirrínico/farmacología , Fitoterapia , Transducción de Señal/efectos de los fármacos , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Línea Celular Tumoral/efectos de los fármacos , Estradiol/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Ácido Glicirrínico/administración & dosificación , Ácido Glicirrínico/uso terapéutico , Humanos , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Raíces de Plantas , Proteínas Proto-Oncogénicas c-akt/metabolismo
11.
Kurume Med J ; 54(1-2): 31-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18332594

RESUMEN

Little is known about the influence of simple limbectomy on the growth of the acetabulum. An experimental study was carried out in ten monkeys divided into two groups: limbectomy only (Group A) and limbectomy with concomitant cartilage resection (Group B). After three years and four months postoperatively, monkeys were sacrificed. Excised joints were examined macro-and microscopically. Degenerative changes in the cartilage and hypertrophy in the joint capsule were noted in all five monkeys of Group B, and in none of Group A. The diameter of the acetabulum was significantly enlarged in Group B (longitudinal diameter: p<0.05, transverse diameter: p<0.01, Mann-Whitney's U test), compared with Group A and the contralateral hips as controls. There was no other significant difference in other soft tissue or osseous components, between two groups. Histologically, the injured limbus was healed with irregular and sparse fibrous tissue in both groups. Fibrillation in the superficial layer of the cartilage and cluster formation was frequently noted in group B, while normal appearance was noted in Group A. This study demonstrated that simple limbectomy dose not affect the growth of the acetabulum, but may cause degenerative changes if the adjacent acetabular cartilage was simultaneously injured.


Asunto(s)
Acetábulo/crecimiento & desarrollo , Extremidades/cirugía , Animales , Macaca
12.
PLoS One ; 12(5): e0175029, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28467441

RESUMEN

The optimal distribution of the reinforcing fibers for stiffening hollow cylindrical composites is explored using the linear elasticity theory. The spatial distribution of the vascular bundles in wild bamboo, a nature-designed functionally graded material, is the basis for the design. Our results suggest that wild bamboos maximize their flexural rigidity by optimally regulating the radial gradation of their vascular bundle distribution. This fact provides us with a plant-mimetic design principle that enables the realization of high-stiffness and lightweight cylindrical composites.


Asunto(s)
Bambusa , Diseño de Equipo , Modelos Teóricos
13.
IEEE Int Conf Rehabil Robot ; 2017: 505-510, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28813870

RESUMEN

Upper limb rehabilitation training for Hemiplegie patients has been conducted mainly by human therapists. Training methods and conditions depend strongly on their experience because of the wide range of individual differences between patients. The force control and sensing functions of rehabilitation robots are expected to be used for the qualitative assessment of next-generation computational rehabilitation. In this study, we developed a simple exercise machine for upper limbs (SEMUL) using an electro-rheological fluid brake, as a safe brake-type robotic rehabilitation system. We also developed a new upper limb training/assessment program, called "WIPE," for the SEMUL. Furthermore, we conducted clinical tests on twelve subjects (six each for the SEMUL training and for general training). We adopted the ABA design methodology for the clinical research tests. The motor functions of upper limbs were assessed using five clinical scores: Fugl-Meyer Assessment (FMA), Brunnstrome recovery stage, Simple Test for Evaluating Hand Function (STEF), Stroke Impairment Assessment Set (SIAS), and Motor Activity Log. Improvements of the FMA, STEF, and SIAS in the SEMUL training groups were found to be higher than those in the general training groups.


Asunto(s)
Terapia por Ejercicio/métodos , Rehabilitación de Accidente Cerebrovascular/métodos , Extremidad Superior/fisiología , Anciano , Diseño de Equipo , Terapia por Ejercicio/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación del Resultado de la Atención al Paciente , Rehabilitación de Accidente Cerebrovascular/instrumentación
14.
Toxicol Lett ; 163(2): 130-41, 2006 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-16280211

RESUMEN

We examined expression profiles of estrogen-responsive genes after treatment with alkylphenols (p-cresol (pC), 4-n-ethylphenol (4EP), 4-n-heptylphenol (4HP), 4-t-octylphenol (4OP) and nonylphenol (NP)), chlorinated phenols (4-chlorophenol (4CP), 4-chloro-3,5-dimethylphenol (CDP), 2,4-dichlorophenol (DCP) and pentachlorophenol (PCP)), parabens (methylparaben (MPB), ethylparaben (EPB) propylparaben (PPB) and butylparaben (BuPB)), or bis- and benzoylphenols (bisphenols A and B and p-hydroxybenzophenone (pHBP)) by means of a DNA microarray assay first to evaluate the estrogenic activity of these chemicals and then to understand the structural basis for the activity. By selecting a set of 120 genes showing greater statistical reliability for estrogen, a more reliable assay for each of the chemicals was achieved and, for the chemicals for which data were available, the results were consistent with those of previously reported estrogen receptor-binding and yeast two-hybrid assays except for chlorinated and few other phenols. Evaluation of the chemicals based on gene function indicated that the genes related to proliferation, transcription and transport were mostly up-regulated while significant numbers of genes related to enzymes and signaling were down-regulated. The genes related to transcription showed the highest degree of variation among the six functional categories (enzymes, signaling, proliferation, transcription, transport and others) for the chemicals with relatively high levels of estrogenic activity. These results indicate that the variations in chemicals and their biological effects can be monitored by the appropriate grouping of estrogen-responsive genes.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Estrógenos no Esteroides/toxicidad , Expresión Génica/efectos de los fármacos , Fenoles/toxicidad , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Análisis por Conglomerados , Estrógenos no Esteroides/química , Estrógenos no Esteroides/clasificación , Femenino , Perfilación de la Expresión Génica , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenoles/química , Fenoles/clasificación , Transducción de Señal , Relación Estructura-Actividad
15.
Phys Rev E ; 93(2): 022406, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26986361

RESUMEN

Bamboo has a distinctive structure wherein a long cavity inside a cylindrical woody section is divided into many chambers by stiff diaphragms. The diaphragms are inserted at nodes and thought to serve as ring stiffeners for bamboo culms against the external load; if this is the case, the separation between adjacent nodes should be configured optimally in order to enhance the mechanical stability of the culms. Here, we reveal the hitherto unknown blueprint of the optimal node spacings used in the growth of wild bamboo. Measurement data analysis together with theoretical formulations suggest that wild bamboos effectively control their node spacings as well as other geometric parameters in accord with the lightweight and high-strength design concept.


Asunto(s)
Fenómenos Mecánicos , Poaceae/crecimiento & desarrollo , Fenómenos Biomecánicos , Modelos Biológicos
16.
Science ; 352(6293): 1559-62, 2016 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-27312046

RESUMEN

The physical properties and elemental abundances of the interstellar medium in galaxies during cosmic reionization are important for understanding the role of galaxies in this process. We report the Atacama Large Millimeter/submillimeter Array detection of an oxygen emission line at a wavelength of 88 micrometers from a galaxy at an epoch about 700 million years after the Big Bang. The oxygen abundance of this galaxy is estimated at about one-tenth that of the Sun. The nondetection of far-infrared continuum emission indicates a deficiency of interstellar dust in the galaxy. A carbon emission line at a wavelength of 158 micrometers is also not detected, implying an unusually small amount of neutral gas. These properties might allow ionizing photons to escape into the intergalactic medium.

17.
FEBS Lett ; 579(7): 1732-40, 2005 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-15757668

RESUMEN

Here, we examined phytoestrogens, isoflavones (genistein, daidzein, glycitein, biochanin A and ipriflavone), flavones (chrysin, luteolin and apigenin), flavonols (kaempferol and quercetin), and a coumestan, a flavanone and a chalcone (coumestrol, naringenin and phloretin, respectively) by means of a DNA microarray assay. A total of 172 estrogen responsive genes were monitored with a customized DNA microarray and their expression profiles for the above phytoestrogens were compared with that for 17beta-estradiol (E2) using correlation coefficients, or R values, after a correlation analysis by linear regression. While R values indicate the similarity of the response by the genes, we also examined the genes by cluster analysis and by their specificity to phytoestrogens (specific to genistein, daidzein or glycitein) or gene functions. Several genes were selected from p53-related genes (CDKN1A, TP53I11 and CDC14), Akt2-related genes (PRKCD, BRCA1, TRIB3 and APPL), mitogen-activated protein kinase-related genes (RSK and SH3BP5), Ras superfamily genes (RAP1GA1, RHOC and ARHGDIA) and AP-1 family and related genes (RIP140, FOS, ATF3, JUN and FRA2). We further examined the extracts from two local crops of soy beans (Kuro-daizu or Mochi-daizu) by comparing the gene expression profiles with those of E2 or phytoestrogens as a first step in utilizing the expression profiles for various applications.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Expresión Génica/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Fitoestrógenos/farmacología , Línea Celular Tumoral , Regulación hacia Abajo , Estradiol/farmacología , Humanos , Estructura Molecular , Fitoestrógenos/química , Extractos Vegetales/farmacología , Glycine max/química , Regulación hacia Arriba
18.
Exp Hematol ; 32(3): 244-53, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15003309

RESUMEN

OBJECTIVE: Fetal hemoglobin inducers such as hemin, butyrate, and hydroxyurea stimulate gamma-globin gene expression by activating the cyclic GMP (cGMP)-dependent pathway. Although cGMP activates the cyclic AMP (cAMP)-dependent pathway by suppressing cGMP-inhibited phosphodiesterase 3 (PDE3), the effects of the cAMP-dependent pathway on gamma-globin gene expression are unknown. MATERIALS AND METHODS: The cAMP-dependent pathway was activated in K562 cells using the adenylate cyclase activator forskolin. Expression of gamma-globin mRNA was examined by primer extension, and transcriptional activity of the gamma-globin gene promoter was determined by reporter gene assays. RESULTS: PDE3 was expressed in K562 cells at a high level. The cAMP-dependent pathway was found to be activated in K562 cells in which the cGMP-dependent pathway was activated by hemin. Activation of the cAMP-dependent pathway by forskolin inhibited hemin-induced expression of gamma-globin mRNA and decreased transcriptional activity of the gamma-globin gene promoter. The levels of phosphorylation of mitogen-activated protein kinases (MAPKs) were not affected by the cAMP-dependent pathway. CONCLUSIONS: These results suggested that the cAMP-dependent pathway, which is independent of MAPK pathways, plays a negative role in gamma-globin gene expression in K562 cells. cAMP and cGMP may have differential roles in the regulation of gamma-globin gene expression in erythroid cells.


Asunto(s)
Adenina/análogos & derivados , AMP Cíclico/fisiología , Células Precursoras Eritroides/metabolismo , Regulación de la Expresión Génica/fisiología , Globinas/biosíntesis , Transducción de Señal/fisiología , 3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Adenina/farmacología , Adenilil Ciclasas/metabolismo , Colforsina/farmacología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/fisiología , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , GMP Cíclico/fisiología , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 3 , Células Precursoras Eritroides/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Globinas/genética , Hemina/farmacología , Humanos , Células K562/efectos de los fármacos , Células K562/metabolismo , Sistema de Señalización de MAP Quinasas , Fosforilación , Regiones Promotoras Genéticas , ARN Mensajero/biosíntesis , Transducción de Señal/efectos de los fármacos , Transcripción Genética
19.
Environ Health Perspect ; 112(7): 773-81, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15159206

RESUMEN

We developed a DNA microarray to evaluate the estrogen activity of natural estrogens and industrial chemicals. Using MCF-7 cells, we conducted a comprehensive analysis of estrogen-responsive genes among approximately 20,000 human genes. On the basis of reproducible and reliable responses of the genes to estrogen, we selected 172 genes to be used for developing a customized DNA microarray. Using this DNA microarray, we examined estrogen activity among natural estrogens (17beta-estradiol, estriol, estrone, genistein), industrial chemicals (diethylstilbestrol, bisphenol A, nonylphenol, methoxychlor), and dioxin. We obtained results identical to those for other bioassays that are used for detecting estrogen activity. On the basis of statistical correlations analysis, these bioassays have shown more sensitivity for dioxin and methoxychlor.


Asunto(s)
Contaminantes Ambientales/toxicidad , Estrógenos/toxicidad , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos , Receptores de Estrógenos/efectos de los fármacos , Bioensayo/métodos , Neoplasias de la Mama/patología , Contaminantes Ambientales/farmacología , Estrógenos/farmacología , Femenino , Humanos , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
20.
J Steroid Biochem Mol Biol ; 86(3-5): 433-42, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14623541

RESUMEN

Estrogen and its receptor play important roles in genesis and malignant progression of estrogen-dependent cancers, together with various growth factors. Functional cross-talk between estrogen-signaling and growth factor-mediated signaling pathways has been reported. Firstly, we show an example of the cross-talk that may alter the effect of antagonist on the breast and endometrial cancer cell growth. Our observations suggest that the constitutively activated MAP kinase-signaling pathway in endometrial cancer cells might enhance the transcriptional activity of ERalpha via phosphorylation of AF-1 domain. This mechanism may cause the growth stimulative effect of tamoxifen on the endometrium. Secondly, we show our recent study for comprehensive understanding of estrogen-signaling pathway using cDNA microarray. According to the results of the expression profiling of estrogen-responsive genes in ER-positive breast cancer cells using large-scale cDNA microarray, the custom-made cDNA microarray, on which only estrogen-responsive genes were loaded, was produced. Using this microarray consisting of the narrowed gene subset, we analyzed estrogen responsiveness of various cell lines and effect of estrogen antagonists. Aim of this study is not only to address the molecular mechanisms of estrogen-dependent growth of breast cancer, but also to develop the new diagnostic tools for responsiveness to hormone therapy of primary breast cancer patients. Finally, in order to understand the local tumor biology including stroma-cancer interaction, we recently developed the new analytical system using ERE-GFP introduced into breast cancer cells. Several observations indicated that these reporter cells were useful for assessment of stimulative effects of stroma cells adjacent to breast cancer on the estrogen-signaling pathway. These studies may provide not only new clues for elucidation of the molecular mechanisms of estrogen-dependent growth of breast cancer, but also assessment of anti-estrogen responses of individual breast cancer for patient-tailored hormone therapy.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias Endometriales/patología , Estrógenos/fisiología , Sustancias de Crecimiento/fisiología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Neoplasias Endometriales/metabolismo , Estradiol/farmacología , Receptor alfa de Estrógeno , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Proteínas Fluorescentes Verdes , Humanos , Proteínas Luminiscentes/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Receptores de Estrógenos/metabolismo , Elementos de Respuesta/genética , Transducción de Señal/efectos de los fármacos , Células del Estroma/metabolismo , Células del Estroma/patología , Tamoxifeno/farmacología
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