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1.
Gesundheitswesen ; 77 Suppl 1: S45-6, 2015 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-23970393
2.
Neuroimage ; 81: 294-305, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23684882

RESUMEN

Successful social interaction requires recognising the intention of another person's communicative gestures. At a neural level, this process may involve neural activity in different systems, such as the mentalizing system (MS) and the mirror neuron system (MNS). The aim of the present study was to explore the neural correlates of communicative gestures during observation and execution of these gestures. Twenty participants watched video clips of an actor executing social gestures (S), non-social gestures (NS) and meaningless gestures (ML). During fMRI data acquisition, participants were asked to observe (O) and subsequently to execute (E) one of two tasks: imitate the gesture presented (IMI) or perform a motor control task (CT). For the contrast IMI>CT we found activations in the core areas of the MNS [inferior parietal lobule (IPL) and inferior frontal cortex, the posterior part of pars opercularis], as well as in areas related to the MS [superior temporal sulcus (STS) and middle cingulate cortex]. For S>NS, we found activations in the left medial orbitofrontal cortex (mOFC), right superior frontal cortex and middle cingulate cortex. The interaction of stimulus condition (S vs NS) and task (IMI vs CT) revealed activation in the right IPL. For the interaction between observation vs execution (O vs E), task (IMI vs CT) and stimulus condition (S vs NS) we found activation in the right mOFC. Our data suggest that imitation is differentially processed in the MNS as well as in the MS. The activation in IPL is enhanced during the processing of social gestures most likely due to their communicative intention. The activation of IPL together with medial frontal areas may contribute to mentalizing processes. The interaction in the mOFC suggests an involvement of self-referential processes in the processing of social gesture.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Gestos , Conducta Imitativa/fisiología , Neuronas Espejo/fisiología , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Adulto Joven
4.
Rev. bras. plantas med ; 14(2): 287-292, 2012. ilus
Artículo en Inglés | LILACS | ID: lil-650668

RESUMEN

Spathodea campanulata is used in traditional medicine in Africa as diuretic and anti-inflammatory. Although few studies have reported the mechanism of antioxidant action, this study evidenced the antioxidant activity of S. campanulata bark and flower extracts and their possible mechanism of action. Ethanol extracts of S. campanulata bark and flowers showed antioxidant activity on lipid peroxidation of liver microsome induced by Fe3+-ascorbic acid. Bark extract was 5 times more efficient than flower extract. The antioxidant activity of flower extract, previously complexed with increasing concentrations of Fe3+ (20 - 100 µM) which resulted in antioxidant activity loss, was shown to be related to iron complex formation. In contrast, the antioxidant activity of bark extract was not inhibited by the previous incubation with Fe3+, although complexation was demonstrated by spectral analysis of the solution. These results suggest an antioxidant mechanism other than Fe3+ complex formation. Therefore, the antioxidant mechanisms of S. campanulata flower and bark extracts are distinct from each other, reflecting the extract heterogeneous composition and the mechanism of action.


Spathodea campanulata é usada na medicina popular na África como diurético e antiinflamatório. Embora poucos estudos relatem o mecanismo de ação antioxidante, neste trabalho foi evidenciado a atividade antioxidante dos extratos da casca e da flor da S. campanulata e o possível mecanismo de ação. Os extratos etanólicos da casca e da flor da S. campanulata mostrou possuir atividade antioxidante sobre a lipoperoxidação de microssoma hepático induzida por Fe3+-ácido ascórbico. O extrato da casca foi 5 vezes mais eficiente que da flor. O extrato da flor foi previamente complexado com concentrações crescentes de Fe3+ (20 - 100 µM) o qual resultou na perda da atividade antioxidante, demonstrando que esta está relacionada com a formação de complexo com o ferro. Por outro lado, a atividade antioxidante do extrato da casca não foi inibida pela prévia incubação com o ferro, embora haja a formação do complexo evidenciado pela análise espectral da solução. Estes resultados sugerem que o mecanismo antioxidante seja outro que não a complexação com o Fe3+. Portanto, o mecanismo antioxidante dos extratos da flor e da casca da S. campanulata é distinto entre si o que reflete a composição heterogênica do extrato e o mecanismo de ação.


Asunto(s)
Liriodendron/efectos adversos , Antioxidantes/análisis , Extractos Vegetales/análisis , Flores/efectos adversos
6.
Cytogenet Genome Res ; 134(2): 88-95, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21555877

RESUMEN

Gliosarcoma, a rare glioblastoma variant, is composed of a glial and a mesenchymal component. Though the mesenchymal portion most commonly resembles a fibrosarcoma, other differentiation patterns have been observed. We present the first genomic characterisation (karyotyping followed by FISH and array comparative genomic hybridisation analysis) of a gliosarcoma with osseous metaplasia. In addition to chromosomal changes often found in gliomas (+7, -10, -13, and -22), the tumour cells also harboured a hitherto unknown t(3;21)(q13∼21;q21∼22).


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Gliosarcoma/genética , Gliosarcoma/patología , Ventrículos Laterales/patología , Anciano , Cromosomas Humanos , Hibridación Genómica Comparativa , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Metaplasia/genética
7.
Phys Rev Lett ; 103(11): 110801, 2009 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-19792359

RESUMEN

We present an x-ray optical approach to overcome the current limitations in spatial resolution of x-ray microscopes. Our new BESSY full-field x-ray microscope operates with an energy resolution up to E/DeltaE=10(4). We demonstrate that under these conditions it is possible to employ high orders of diffraction for imaging. Using the third order of diffraction of a zone plate objective with 25 nm outermost zone width, 14 nm lines and spaces of a multilayer test structure were clearly resolved. We believe that high-order imaging paves the way towards sub-10-nm real space x-ray imaging.

8.
J Synchrotron Radiat ; 15(Pt 1): 26-35, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18097075

RESUMEN

Using the scanning transmission X-ray microscope at BESSY II, colloidal structures from a Chernozem soil have been studied with a spatial resolution around 60 nm and a spectral resolution of 1,700 at the K-absorption edge of carbon. Elemental mapping has been used to determine the distribution of organic matter within the colloidal structures. Spectra have been extracted from image stacks to obtain information about the chemical state. For the analysis of the latter, principal component analysis and cluster analysis have been applied. It was possible, for example, to discriminate clay particles against organic components.

9.
Scand J Clin Lab Invest ; 68(2): 93-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17852828

RESUMEN

OBJECTIVE: High expression of CD7 on CD34+ cells (>20 %) has been shown to be associated with inferior prognosis in chronic myeloid leukaemia (CML), but the reason has not been unravelled. We set out to investigate whether lack of dendritic cells or der(9)t(9;22)(q34;q11) deletions might be correlated with increased CD7 expression on CD34+ cells in CML. MATERIAL AND METHODS: We identified 43 patients in our cohort of CML patients in the first chronic phase in whom we were able to assess the expression of CD7 on CD34+ cells. der(9)t(9;22) deletions were evaluated by FISH (fluorescent in situ hybridization) analyses and the proportions of plasmacytoid and myeloid dendritic cells were assessed by flow cytometry. RESULTS: High and low expressions of CD7 on CD34+ cells were found in 19 and 24 patients, respectively. Two out of 20 patients examined had a der(9)t(9;22)(q34;11) deletion, one patient with high expression and one with low expression of CD7 on CD34+ cells. The proportions of plasmacytoid dendritic cells (PDCs) and myeloid dendritic cells (MDCs) were reduced in a majority of patients in our cohort, but no correlation was found between high or low expression of CD7 on CD34+ cells and the proportion of dendritic cells. CONCLUSIONS: A high proportion of CD34+CD7+ cells in patients with CML is not associated with der(9)t(9;22)(q34;q11) deletions. Nor did we find any correlation between CD7 expression on CD34+ cells and lack of dendritic cells. High expressions of CD7 on CD34+ cells and der(9)t(9;22)(q34;q11) deletions seem to be independent prognostic markers in CML.


Asunto(s)
Antígenos CD34/metabolismo , Antígenos CD7/metabolismo , Cromosomas Humanos Par 9 , Células Dendríticas/inmunología , Leucemia Mielógena Crónica BCR-ABL Positiva/inmunología , Adulto , Anciano , Deleción Cromosómica , Femenino , Humanos , Hibridación Fluorescente in Situ , Subgrupos Linfocitarios , Masculino , Persona de Mediana Edad
11.
Cytogenet Genome Res ; 118(1): 13-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17901695

RESUMEN

The dic(7;9)(p11 approximately 13;p11 approximately 13) is a recurrent chromosomal abnormality in acute lymphoblastic leukemia (ALL), mainly of B-lineage. Although more than 20 dic(7;9)-positive ALLs have been reported to date, the molecular genetic consequences of this aberration are unknown. We performed tiling resolution (32K) genome-wide array-based comparative genomic hybridization (array CGH) analysis of three cases with dic(7;9) in order to characterize the breakpoints on 7p and 9p. The analysis showed a clustering of breakpoints within 9p13.1 in all three cases and within 7p11.2 in two cases; the array CGH revealed two different breakpoints - 7p12.1 and 7p14.1 - in the remaining case. Based on these findings the abnormality should hence be designated dic(7;9)(p11.2 approximately 12.1;p13.1). Locus-specific fluorescence in situhybridization analysis of one of the cases narrowed down the 7p11.2 breakpoint to a <500-kb segment in this sub-band, a region containing three known genes. Unfortunately, lack of material precluded further molecular genetic studies, and it thus remains unknown whether the pathogenetically important outcome of the dic(7;9) is formation of a chimeric gene or loss of 7p and/or 9p material.


Asunto(s)
Linfoma de Burkitt/genética , Cromosomas Humanos , Hibridación de Ácido Nucleico , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Persona de Mediana Edad
12.
Cytogenet Genome Res ; 114(2): 126-30, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16825763

RESUMEN

Isochromosome 7q - i(7q) - is seen in a wide variety of hematologic malignancies and solid tumors, often as a secondary change to a characteristic primary translocation. Despite its high frequency, nothing is known about the formation and the pathogenetic outcome of this abnormality. To address these issues, we performed a detailed fluorescence in situ hybridization (FISH) investigation of four acute lymphoblastic leukemias, one acute myeloid leukemia, and two myxoid liposarcomas with i(7q). Using FISH with bacterial artificial chromosomes (BACs) mapping between 7p12.2 and 7q11.2, the breakpoints (BPs) in all seven cases were shown to cluster to an approximately 340 kb segment at 7p11.2, covered by the overlapping BAC probes RP11-760D2 and RP11-10F11. Thus, the i(7q) should formally be designated idic(7) (p11.2). In one of the cases, FISH with fosmids could narrow down the BP further to an 80-kb sequence delineated by G248P81983A10 and G248P8793H7. No known genes are located in the 340-kb BP cluster region, indicating that the idic(7)(p11.2) does not result in a fusion or deregulation of genes in this segment. The pathogenetically important outcome is thus likely to be an altered gene expression because of copy number changes. The clustering of breakpoints might be due to frequent intrachromosomal duplicons in the BP region.


Asunto(s)
Rotura Cromosómica/genética , Cromosomas Humanos Par 7/genética , Isocromosomas/genética , Leucemia/genética , Leucemia/patología , Liposarcoma Mixoide/genética , Liposarcoma Mixoide/patología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Persona de Mediana Edad
13.
J Pathol ; 209(2): 258-64, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16583359

RESUMEN

Marginal zone differentiation of follicular lymphomas (FL), sometimes referred to as monocytoid B-cell differentiation, is a relatively uncommon phenomenon. Recently, this type of differentiation was also linked to secondary cytogenetic aberrations of chromosome 3 in a small number of patients. We have analysed 131 primary nodal FL with t(14;18)(q32;q21) for secondary cytogenetic aberrations previously described as recurrent in marginal zone lymphomas (MZL) to identify their frequency and possible association with morphological evidence of marginal zone differentiation. We searched for trisomy of chromosomes 3, 12, and 18, gains of chromosome arm 3q, deletions of chromosome arm 7p, structural anomalies with break-points in 1q21 and 1p34, as well as the t(1;2)(p22;p12), t(1;14)(p22;q32), t(3;14)(q27;q32), t(6;14)(p21;q32), and t(11;18)(q21;q21) translocations. At least focal morphological evidence of marginal zone differentiation occurred in 35/131 (27%) FL with t(14;18)(q32;q21) as the primary chromosomal abnormality. None of the recurrent balanced translocations characteristic of extranodal MZL were seen secondarily in the nodal FLs with t(14;18)(q32;q21). However, 43/131 (33%) cases had at least one of the above secondary cytogenetic aberrations previously reported as recurrent aberrations in MZL and, when combined, these were significantly more frequent in FL with morphological evidence of marginal zone differentiation (p<0.0001, two-sided Fisher's exact test). Aberrations of chromosome 3 and, in particular, trisomy 3 occurred frequently in FL with marginal zone differentiation (p=0.002 and p<0.0001, respectively, two-sided Fisher's exact test), while chromosome 21, 22, and X chromosome aberrations, which have not been described previously as recurrent in MZL, were also significantly associated with marginal zone differentiation in FL (p=0.002, p=0.037, p=0.039, respectively, two-sided Fisher's exact test).


Asunto(s)
Aberraciones Cromosómicas , Linfoma Folicular/genética , Translocación Genética/genética , Diferenciación Celular/genética , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 12/genética , Cromosomas Humanos Par 18/genética , Cromosomas Humanos Par 3/genética , Cromosomas Humanos Par 7/genética , Análisis Citogenético/métodos , Humanos , Inmunofenotipificación/métodos , Linfoma Folicular/patología , Fenotipo , Trisomía/genética
14.
Chemosphere ; 61(10): 1427-38, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15992860

RESUMEN

To study the recent contamination history of DDT (1,1,1-trichloro-2,2-bis(chlorophenyl)ethane) and its metabolites, as well as methoxychlor (1,1,1-trichloro-2,2-bis(p-methoxyphenyl)ethane), chlorfenson (4-chlorophenyl-p-chlorobenzenesulfonate), and further halogenated aromatics, a sediment core was collected from the Teltow Canal in Berlin (Germany). The sampling site is located nearby a former industrial point source, where recently analyses on pre-samples have indicated high concentrations of halogenated organic compounds. The deposition time of the investigated sediments was determined by gamma-spectrometrical dating. Pollution trends of selected contaminants were attributed to a time period between 5 and 10 years. Concentration profiles reflect not only the recent pollution history of these compounds, but also the time-depending effects of the ban, restriction and termination of DDT-production in the German Democratic Republic (GDR). DDT and other chlorinated aromatic compounds were produced onsite until the late 1980s. Maximum values of 133 mg kg(-1) (dry weight) for p,p'-DDD (1,1-dichloro-2,2-bis(chlorophenyl)ethane) and approximately 100 mg kg(-1) (dry weight) for p,p'-DDMS (1-chloro-2,2-bis(chlorophenyl)ethane), main metabolites of the anaerobic degradation of DDT, were determined. The occurrence of all selected contaminants, most of which have been banned more than 10 years ago, demonstrate recent contamination pathways, and the necessity of a continuous long-term monitoring of the affected environment.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Halógenos/análisis , Contaminantes Químicos del Agua/análisis , Berlin , DDT/análisis , DDT/metabolismo , Sedimentos Geológicos/química , Plaguicidas/análisis , Contaminantes del Suelo/análisis
15.
Environ Microbiol ; 6(12): 1264-86, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15560824

RESUMEN

A major challenge in microbiology is the elucidation of the genetic and ecophysiological basis of habitat specificity of microbes. Pseudomonas putida is a paradigm of a ubiquitous metabolically versatile soil bacterium. Strain KT2440, a safety strain that has become a laboratory workhorse worldwide, has been recently sequenced and its genome annotated. By drawing on both published information and on original in silico analysis of its genome, we address here the question of what genomic features of KT2440 could explain or are consistent with its ubiquity, metabolic versatility and adaptability. The genome of KT2440 exhibits combinations of features characteristic of terrestrial, rhizosphere and aquatic bacteria, which thrive in either copiotrophic or oligotrophic habitats, and suggests that P. putida has evolved and acquired functions that equip it to thrive in diverse, often inhospitable environments, either free-living, or in close association with plants. The high diversity of protein families encoded by its genome, the large number and variety of small aralogous families, insertion elements, repetitive extragenic palindromic sequences, as well as the mosaic structure of the genome (with many regions of 'atypical' composition) and the multiplicity of mobile elements, reflect a high functional diversity in P. putida and are indicative of its evolutionary trajectory and adaptation to the diverse habitats in which it thrives. The unusual wealth of determinants for high affinity nutrient acquisition systems, mono- and di-oxygenases, oxido-reductases, ferredoxins and cytochromes, dehydrogenases, sulfur metabolism proteins, for efflux pumps and glutathione-S-transfereases, and for the extensive array of extracytoplasmatic function sigma factors, regulators, and stress response systems, constitute the genomic basis for the exceptional nutritional versatility and opportunism of P. putida , its ubiquity in diverse soil, rhizosphere and aquatic systems, and its renowned tolerance of natural and anthropogenic stresses. This metabolic diversity is also the basis of the impressive evolutionary potential of KT2440, and its utility for the experimental design of novel pathways for the catabolism of organic, particularly aromatic, pollutants, and its potential for bioremediation of soils contaminated with such compounds as well as for its application in the production of high-added value compounds.


Asunto(s)
Adaptación Fisiológica/genética , Metabolismo Energético/genética , Genoma Bacteriano , Pseudomonas putida/genética , Pseudomonas putida/fisiología , Microbiología del Suelo , Proteínas Bacterianas/genética , Transporte Biológico Activo/genética , Citocromos/genética , Elementos Transponibles de ADN , Dioxigenasas/genética , Ferredoxinas/genética , Genes Reguladores , Islas Genómicas , Genómica , Glutatión Transferasa/genética , Secuencias Repetitivas Esparcidas , Oxigenasas de Función Mixta/genética , Oxidorreductasas/genética , Factor sigma/genética , Transducción de Señal/genética , Azufre/metabolismo
16.
Magn Reson Med ; 52(3): 582-9, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15334578

RESUMEN

Diffusion tensor imaging (DTI) is an established method for characterizing and quantifying ultrastructural brain tissue properties. However, DTI-derived variables are affected by various sources of signal uncertainty. The goal of this study was to establish an objective quality measure for DTI based on the nonparametric bootstrap methodology. The confidence intervals (CIs) of white matter (WM) fractional anisotropy (FA) and Clinear were determined by bootstrap analysis and submitted to histogram analysis. The effects of artificial noising and edge-preserving smoothing, as well as enhanced and reduced motion were studied in healthy volunteers. Gender and age effects on data quality as potential confounds in group comparison studies were analyzed. Additional noising showed a detrimental effect on the mean, peak position, and height of the respective CIs at 10% of the original background noise. Inverse changes reflected data improvement induced by edge-preserving smoothing. Motion-dependent impairment was also well depicted by bootstrap-derived parameters. Moreover, there was a significant gender effect, with females displaying less dispersion (attributable to elevated SNR). In conclusion, the bootstrap procedure is a useful tool for assessing DTI data quality. It is sensitive to both noise and motion effects, and may help to exclude confounding effects in group comparisons.


Asunto(s)
Mapeo Encefálico , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Anisotropía , Artefactos , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Movimiento , Proyectos de Investigación , Estadísticas no Paramétricas
17.
Br J Cancer ; 91(4): 775-82, 2004 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-15266323

RESUMEN

The issue of whether multiple, ipsilateral or bilateral, breast carcinomas represent multiple primary tumours or dissemination of a single carcinomatous process has been difficult to resolve, especially for individual patients. We have addressed the problem by comparative genomic hybridisation analysis of 26 tumours from 12 breast cancer patients with multiple ipsilateral and/or bilateral carcinoma lesions. Genomic imbalances were detected in 25 of the 26 (96%) tumours. Using the genomic imbalances detected in these 26 lesions as well as those previously found by us in an independent series of 35 unifocal breast carcinomas, we compared a probabilistic model for likelihood of independence with unsupervised hierarchical clustering methodologies to determine the clonal relatedness of multiple tumours in breast cancer patients. We conclude that CGH analysis of multiple breast carcinomas followed by unsupervised hierarchical clustering of the genomic imbalances is more reliable than previous criteria to determine the tumours' clonal relationship in individual patients, that most ipsilateral breast carcinomas arise through intramammary spreading of a single breast cancer, and that most patients with bilateral breast carcinomas have two different diseases.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Carcinoma/genética , Carcinoma/patología , Aberraciones Cromosómicas , Modelos Estadísticos , Neoplasias Primarias Múltiples/genética , Neoplasias Primarias Múltiples/patología , Adulto , Células Clonales , Femenino , Lateralidad Funcional , Humanos , Invasividad Neoplásica , Hibridación de Ácido Nucleico
18.
Environ Microbiol ; 5(12): 1257-69, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14641572

RESUMEN

The genome sequence of Pseudomonas putida strain KT2440, a nutritionally versatile, saprophytic and plant root-colonizing Gram-negative soil bacterium, was recently determined by K. E. Nelson et al. (2002, Environ Microbiol 4: 799-808). Here, we present a two-dimensional gel protein reference map of KT2440 cells grown in mineral salts medium with glucose as carbon source. Proteins were identified by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) analysis, in conjunction with an in-house database developed from the genome sequence of KT2440, and approximately 200 two-dimensional gel spots were assigned. The map was used to assess the genomic response of KT2440 to iron limitation stress and to compare this response with that of the closely related facultative human pathogen Pseudomonas aeruginosa strain PAO1. The synthesis of about 25 proteins was affected in both strains, including four prominent upregulated ferric uptake regulator (Fur) protein-dependent proteins, but there were also striking differences in their proteome responses, for example in the expression of superoxide dismutases (Sod), which may indicate important roles of iron-responsive functions in the adaptation of these two bacteria to different lifestyles. The Sod enzyme of KT2440 was shown to be a novel heterodimer of the SodA and SodB polypeptides.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteoma/análisis , Pseudomonas putida/química , Adaptación Biológica , Secuencia de Aminoácidos , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Proteínas Bacterianas/fisiología , Dimerización , Electroforesis en Gel Bidimensional , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Hierro/metabolismo , Datos de Secuencia Molecular , Subunidades de Proteína/análisis , Pseudomonas putida/genética , ARN Mensajero/análisis , Regulón , Proteínas Represoras/genética , Proteínas Represoras/fisiología , Alineación de Secuencia , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Superóxido Dismutasa/análisis , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Transcripción Genética
19.
Anticancer Res ; 23(3A): 2179-83, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12894594

RESUMEN

The Coding Region Determinant-Binding Protein (CRD-BP) is an RRM and KH-domain-containing protein that recognizes specifically at least three RNAs. It binds to one of the two c-myc mRNA instability elements, to the 5'Un Translated Region (UTR) of the leader 3 IGF-II mRNA and to the oncofetal H19 RNA. CRD-BP has been assigned a role in stabilizing c-myc mRNA by preventing its endonucleolytic cleavage and in repressing the translation of the leader 3 IGF-II mRNA, the major embryonic species of this message. CRD-BP is normally expressed only in fetal tissues. However, its expression is detected in primary tumors and transformed cell lines of different origins. The vast majority of colon (80%) and breast (60%) tumors and sarcomas (73%) express CRD-BP whereas in other tumor types, for example prostate carcinomas, its expression is rare. CRD-BP expression has also been detected in benign tumors such as breast fibroadenomas, meningiomas and other benign mesenchymal tumors, implying a role for this gene in abnormal cell proliferation. In breast carcinomas, CRD-BP expression and or gene copy number gains in the region encompassing the c-myc locus were detected in approximately 75% of tumors, implying that the deregulated expression of c-myc may be more widespread than previously believed. Infiltrated lymph nodes, corresponding to CRD-BP-positive primary tumors, were also found positive indicating that monitoring for CRD-BP could prove useful for the detection and monitoring of disseminated disease.


Asunto(s)
Antígenos de Neoplasias/fisiología , Proteínas Proto-Oncogénicas c-myc/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/fisiología , Animales , Antígenos de Neoplasias/biosíntesis , Antígenos de Neoplasias/genética , Regulación del Desarrollo de la Expresión Génica , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Proto-Oncogénicas c-myc/biosíntesis , ARN Mensajero/genética , Proteínas de Unión al ARN/biosíntesis , Proteínas de Unión al ARN/genética
20.
Cytogenet Genome Res ; 97(1-2): 13-9, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12438732

RESUMEN

Supernumerary ring chromosomes and/or giant marker chromosomes are often seen in soft-tissue tumors of low-grade or borderline malignancy, such as well-differentiated liposarcomas or atypical lipomas. Classic cytogenetic banding techniques have proved insufficient to identify the genomic composition and structure of such rings and markers, but fluorescent in situ hybridization (FISH) studies have shown that they consist mainly of amplified material from chromosome 12, more specifically from bands 12q13-->q15. We have used the new FISH-based screening techniques comparative genomic hybridization (CGH) and multicolor-FISH (M-FISH) in combination with G-banding and analysis by chromosome- and locus-specific fluorescent in situ probes to examine in detail the karyotypic characteristics of 22 lipomatous tumors, most of them classified histologically as well-differentiated liposarcomas, selected because they had been shown to harbor rings and/or marker chromosomes. M-FISH, in contrast to G- banding, was found to be informative with regard to the chromosomal origin of the rings and other markers present, whereas CGH and hybridizations with locus-specific probes helped identify which subchromosomal regions were involved. We found that chromosome bands 12q15-->q21 were always gained, with 12q15-->q21 being amplified (i.e., a green-to-red ratio >2 by CGH) in 14 of 22 tumors. In three tumors, two distinct but close amplicons in 12q could be identified, corresponding to bands 12q13-->q15 and 12q21. The genomic segment 1q21-->q23 was gained in 12 cases, reaching the level of amplification in seven. Bands 6q24 and 7p15, whose pathogenetic involvement in liposarcomas has not been reported previously, were gained in three cases each. In addition, the rings and giant markers often contained interspersed sequences from several other chromosomes that did not give an equally clear impression of being nonrandomly involved.


Asunto(s)
Aberraciones Cromosómicas , Lipoma/genética , Liposarcoma/genética , Cromosomas en Anillo , Biomarcadores de Tumor/genética , Diferenciación Celular , Bandeo Cromosómico , Cromosomas Artificiales de Levadura/genética , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Lipoma/patología , Liposarcoma/patología
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