Relaciones entre niños gitanos y no gitanos dentro del marco educativo.

Se estudia la situación de integración e inserción de los niños y niñas gitanos en relación a los niños payos que estudian Educación Primaria en colegios públicos y concertados de Burgos capital. Se investiga dentro del contexto educativo y con el juego como centro de las conexiones entre sujetos. En el estudio descriptivo han participado 219 alumnos de cuarto, quinto y sexto curso de Educación Primaria (98 niñas y 121 niños), de ellos 10 pertenecen a la etnia gitana, de los cuales tres de ellos tiene un solo progenitor gitano. Dichos sujetos pertenecen a cuatro colegios de Burgos Capital, tres de ellos públicos y uno concertado. El instrumento empleado en la investigación consiste e un cuestionario anónimo dirigido a los alumnos y alumnas. Un gran número de niños y niñas payos de la muestra desconoce la existencia de poblados marginales, aunque tampoco el alumnado gitano conoce todos los poblados gitanos de Burgos. Ambas etnias se relacionan principalmente en el colegio, de forma progresiva se van reduciendo las interacciones desde jugar en la calle, el parque, fiestas, y campamentos. Las interacciones entre niños y niñas payos con niños y niñas gitanas fuera del colegio son escasas. Todos los niños y niñas de etnia gitana afirman tener amigos y amigas payos, además aseguran que juegan con ellos en el recreo.

Aproximación al estudio de la didáctica de la ortografía : descripción y análisis cacográfico del alumnado de 5º de E.G.B. en Gran Canaria.

Estudiar el análisis de las faltas ortográficas cometidas por los discentes de Gran Canaria. Extracción de los vocablos que encierran mayor dificultad para su correcta escritura. Determinar los tipos de errores ortográficos que el alumnado de Gran Canaria comete con mayor frecuencia. Observación de algunos de los aspectos que de forma indirecta pueden influir en el nivel ortográfico del escolar. Para ello examinar la relación existente entre el número de errores cometidos en los diferentes temas de redacción y las variables sexo, edad, localidad, tipo de enseñanza y profesión del progenitor. Se trabaja a través de un muestreo constituido por 1700 redacciones, realizadas por los alumnos que en los años escolar 1982-83 cursaban quito de Educación General Básica en centros escolares de la isla de Gran Canaria. Se visitan un total de 33 centros de enseñanza situados en los diversos municipios que constituyen la isla. La corrección de las redacciones y la evaluación posterior de los resultados obtenidos, permite la configuración de varios listados: de cacografías, de tipos de errores ortográficos y de vocablos que presentan dificultades ortográficas. Así mismo, se observa la influencia que las variables localidad, sexo, tipo de enseñanza, edad y estatus socioeconómico de la familia, pueden tener en el rendimiento ortográfico del alumnado. Para la realización de la prueba se diseño una plantilla que estuviera encabezada por los datos personales del alumno: nombre, edad, centro en el que cursaba sus estudios, localidad y profesión del padre. Esto permite dilucitar el ambiente en que cada escolar desarrollaba su actividad, con el fin de observar las posibles relaciones establecidas entre el medio y las cacografías que presentara. Se comprueba que las cacografías más usuales entre los alumnos de Gran Canaria, son las relativas a la acentuación de las palabras, tendiendo a omitir el acento más que a utilizarlo incorrectamente, y las de transformación de letras, entre las que se destacan los errores que se han considerado de origen fonético. Los vocablos que se constatan con mayor índice de error son: también y más. Los cuales encabezan los listados de cacografías y de vocablos más significativos. Desde el punto de vista gramatical, se observa que donde más errores comenten los escolares es en los sustantivos y en los verbos, hecho que se justifica ante la usualidad lingüística de los mismos. Es evidente la influencia que el sector de población, tipo de enseñanza y sexo ejercen en el alumnado condicionando su aprendizaje ortográfico. Así, muestran mejor rendimiento en esta disciplina las alumnas del sector urbano que efectúan sus estudios en centros de enseñanza privada, mientras que el peor nivel ortográfico se halla entre los varones del sector turístico que asisten a colegios públicos. El rendimiento ortográfico, es respectivamente, directa e inversamente proporcional al estrato socio-económico del alumno y a su edad. La cantidad de incorrecciones puede estar en función del tema de la composición y de la influencia emocional que éste suscite en el escolar. No se observa en el estudio mejor rendimiento ortográfico en los temas que se encuentran incluidos en las áreas de aprendizaje.

Niños con trastornos familiares.

Discutir y desarrollar si la familia se encuentra en crisis en la época actual, deteniéndose en su estudio y en las repercusiones que puede acarrear su ausencia en la infancia. El trabajo se estructura siguiendo los siguientes conceptos, en primer lugar atendiendo al estudio de la afectividad, la familia, su importancia, la labor de sus distintos miembros y la influencia de éstos sobre el niño, estudio de los niños con situación familiar anómala (hijos de madre soltera, huérfanos o hijos de padres divorciados), y posibles soluciones para que conseguir el mayor bienestar de los niños. En el capítulo primero desarrolla el concepto de afectividad, la vida afectiva del niño constituye uno de los aspectos más difíciles de la psicología evolutiva, de hecho los niños privados de afecto se desarrollan de forma diferente a los niños que sí gozan de ella. En el capítulo segundo la importancia de la familia marcando pautas de comportamiento social de los individuos, para afrontar las nuevas relaciones de la escuela adquiriendo costumbres, y reacciones afectiva, pasando de la dependencia a la independencia. El papel de la madre y los riesgos de la ausencia materna, así como las actitudes maternas inadecuadas, la importancia de la figura paterna los hermanos y los abuelos. En el capítulo tercero se explica la situación anómala familiar y sus repercusiones en los hijos atendiendo a los casos en los que la situación familiar es del tipo, madre soltera, carencia de familia normal, hijos de padres divorciados o hijos de padres separados, padres adoptivos. En el capítulo cuarto nos muestra las posibles soluciones a la situación familiar anómala. La adopción, los padres adoptivos, las residencias infantiles u orfanatos, algunos aspectos del desarrollo infantil. 1) El niño necesita al nacer de otros hombres para llegar a su propio acabamiento humano, ya que es un ser indefenso. Precisa estar rodeado de las mejores condiciones para así alcanzar su madurez de hombre, 2) Es necesario cuidar los hogares buenos porque de ellos saldrán buenos ciudadanos, 3) La madre es la persona más importante para el normal desarrollo del niño, si hay ausencia de ella se pueden producir graves irregularidades en el desarrollo, 4) El papel del padre, aunque diferente del de la madre, también es importante desde los primeros momentos de la vida del niño, al principio porque apoya a la madre en su labor y después porque mantiene y da seguridad a la familia, 5) Muchas veces los padres actúan mal ante los hijos, tienen actitudes inadecuadas que son sumamente perjudiciales para el normal desenvolvimiento del hijo, 6) Los hermanos facilitan la socialización del niño y así le preparan para la sociedad adulta futura a la que se tendrá que enfrentar cuando crezca, 7) El hijo ilegítimo, aun suponiendo que tenga una madre madura y buena, siempre estará en desventaja respecto a otros niños legítimos, 8) Es alarmante la relación que hay entre el hijo delincuente y hogar en conflicto, 9) Ante el problema de la muerte de un padre lo que el niño necesita es que el otro progenitor sea maduro y equilibrado,10) Ante los niños que se quedan solos o que tienen un núcleo familiar que no puede atenderles, la sociedad ha de actuar supliendo en la medida de lo posible a esa familia.

El síndrome de alienación parental como elemento valorativo de violencia familiar psicológica

El síndrome de alienación parental (SAP) es aquel proceso realizado por el progenitor consistente en programar una conducta de rechazo al otro progenitor sin una justificación objetiva. La conducta alienante la realiza el progenitor con el derecho a la tenencia del hijo; sin embargo, el otro progenitor ante tal conducta, cuando tiene acceso al hijo (a través de su derecho a la visita) suele realizar la misma conducta criticable y comienza a generar en el hijo una situación de inestabilidad dado que le exigen una conducta de fidelidad/rechazo que le es imposible de cumplir (conflicto de lealtades). En la mayoría de casos la conducta de los progenitores alienantes, provoca una reacción de temor en el otro, el cual consideramos “progenitor débil”, por cuanto es víctima de violencia familiar (tanto física como psicológica).

NG2 cells differentiate into astrocytes in cerebellar slices

NG2-glia are an abundant population of glial cells that have been considered by many to be oligodendrocyte progenitor cells (OPCs). However, growing evidence suggests that NG2-glia may also be capable of differentiating into astrocytes and neurons under certain conditions. Here, we have examined NG2-glia in cerebellar slices, using transgenic mice in which the astroglial marker glial specific protein (GFAP) drives expression of the reporter gene enhanced green fluorescent protein (EGFP). Immunolabelling for NG2 shows that NG2-glia and GFAP-EGFP astroglia are separate populations in most areas of the brain, although a substantial population of NG2-glia in the pons also express the GFAP-EGFP reporter. In the cerebellum, NG2-glia did not express EGFP, either at postnatal day (P)12 or P29-30. We developed an organotypic culture of P12 cerebellar slices that maintain cytoarchitectural integrity of Purkinje neurons and Bergmann glia. In these cultures, BrdU labelling indicates that the majority of NG2-glia enter the cell cycle within 2 days in vitro (DIV), suggesting that NG2-glia undergo a [`]reactive' response in cerebellar cultures. After 2 DIV NG2-glia began to express the astroglial reporter EGFP and in some cases the respective GFAP protein. However, NG2-glia did not acquire phenotypic markers of neural stem cells or neurons. The results suggest that NG2-glia are not lineage restricted OPCs and are a potential source of astrocytes in the cerebellum.

Sequence analysis of the cupin gene family in Synechocystis PCC6803

The recently described cupin superfamily of proteins includes the germin and germinlike proteins, of which the cereal oxalate oxidase is the best characterized. This superfamily also includes seed storage proteins, in addition to several microbial enzymes and proteins with unknown function. All these proteins are characterized by the conservation of two central motifs, usually containing two or three histidine residues presumed to be involved with metal binding in the catalytic active site. The present study on the coding regions of Synechocystis PCC6803 identifies a previously unknown group of 12 related cupins, each containing the characteristic two-motif signature. This group comprises 11 single-domain proteins, ranging in length from 104 to 289 residues, and includes two phosphomannose isomerases and two epimerases involved in cell wall synthesis, a member of the pirin group of nuclear proteins, a possible transcriptional regulator, and a close relative-of a cytochrome c551 from Rhodococcus. Additionally, there is a duplicated, two-domain protein that has close similarity to an oxalate decarboxylase from the fungus Collybia velutipes and that is a putative progenitor of the storage proteins of land plants.

The role of Wnt signalling in the development of somites and neural crest

The Wnt family of secreted signalling molecules controls a wide range of developmental processes in all metazoans. In this investigation we concentrate on the role that members of this family play during the development of (1) the somites and (2) the neural crest. (3) We also isolate a novel component of the Wnt signalling pathway called Naked cuticle and investigate the role that this protein may play in both of the previously mentioned developmental processes. (1) In higher vertebrates the paraxial mesoderm undergoes a mesenchymal-to-epithelial transformation to form segmentally organised structures called somites. Experiments have shown that signals originating from the ectoderm overlying the somites or from midline structures are required for the formation of the somites, but their identity has yet to be determined. Wnt6 is a good candidate as a somite epithelialisation factor from the ectoderm since it is expressed in this tissue. In this study we show that injection of Wnt6-producing cells beneath the ectoderm at the level of the segmental plate or lateral to the segmental plate leads to the formation of numerous small epithelial somites. We show that Wnts are indeed responsible for the epithelialisation of somites by applying Wnt antagonists which result in the segmental plate being unable to form somites. These results show that Wnt6, the only member of this family to be localised to the chick paraxial ectoderm, is able to regulate the development of epithelial somites and that cellular organisation is pivotal in the execution of the differentiation programmes. (2) The neural crest is a population of multipotent progenitor cells that arise from the neural ectoderm in all vertebrate embryos and form a multitude of derivatives including the peripheral sensory neurons, the enteric nervous system, Schwann cells, pigment cells and parts of the craniofacial skeleton. The induction of the neural crest relies on an ectodermally derived signal, but the identity of the molecule performing this role in amniotes is not known. Here we show that Wnt6, a protein expressed in the ectoderm, induces neural crest production. (3) The intracellular response to Wnt signalling depends on the choice of signalling cascade activated in the responding cell. Cells can activate either the canonical pathway that modulates gene expression to control cellular differentiation and proliferation, or the non-canonical pathway that controls cell polarity and movement (Pandur et al. 2002b). Recent work has identified the protein Naked cuticle as an intracellular switch promoting the non-canonical pathway at the expense of the canonical pathway. We have cloned chick Naked cuticle-1 (cNkd1) and demonstrate that it is expressed in a dynamic manner during early embryogenesis. We show that it is expressed in the somites and in particular regions where cells are undergoing movement. Lastly our study shows that the expression of cNkd1 is regulated by Wnt expression originating from the neural tube. This study provides evidence that non-canonical Wnt signalling plays a part in somite development.

Development of the mammalian urethra is controlled by Fgfr2-IIIb

Development of external genitalia in mammalian embryos requires tight coordination of a complex series of morphogenetic events involving outgrowth, proximodistal and dorsoventral patterning, and epithelial tubulogenesis. Hypospadias is a congenital defect of the external genitalia that results from failure of urethral tube closure. Although this is the second most common birth defect in humans, affecting one in every 250 children, the molecular mechanisms that regulate morphogenesis of the mammalian urethra are poorly understood. We report that mice lacking the IIIb isoform of fibroblast growth factor receptor 2 (Fgfr2) exhibit severe hypospadias. Urethral signaling regions, as indicated by Shh and Fgf8 expression, are established in Fgfr2-IIIb null mice; however, cell proliferation arrests prematurely and maturation of the urethral epithelium is disrupted. Fgfr2-IIIb(-/-) mutants fail to maintain the progenitor cell population required for uroepithelial renewal during tubular morphogenesis. In addition, we show that antagonism of the androgen receptor (AR) leads to loss of Fgfr2-IIIb and Fgf10 expression in the urethra, and an associated hypospadias phenotype, suggesting that these genes are downstream targets of AR during external genital development. Genitourinary defects resulting from disruption of AR activity, by either genetic or environmental factors, may therefore involve negative regulation of the Fgfr2 pathway. This represents the first example of how the developing genitourinary system integrates cues from systemically circulating steroid hormones with a locally expressed growth factor pathway.

Is there such a thing as Kalmia x Rhododendron?

Two putative hybrids between Kalmia and Rhododendron, their suspected progenitor species and related taxa were submitted to DNA sequencing of cpDNA trnL-F and nrDNA ITS regions in order to test whether there was DNA sequence evidence both for hybridization per se and for the direction of the cross should one be evident. Comparison of eight DNA sequences from these putative hybrids with Rhododendron and Kalmia species showed clear evidence of origin within Rhododendron. No evidence of Kalmia DNA was detected. These putative intergeneric hybrids appear to be mutants of Rhododendron and not of hybrid origin.

The pro-inflammatory oxidant hypochlorous acid induces Bax-dependent mitochondrial permeabilisation and cell death through AIF-/EndoG-dependent pathways

At sites of chronic inflammation, such as in the inflamed rheumatoid joint, activated neutrophils release hydrogen peroxide (H2O2) and the enzyme myeloperoxidase to catalyse the formation of hypochlorous acid (HOCl). 3-chlorotyrosine, a marker of HOCl in vivo, has been observed in synovial fluid proteins from rheumatoid arthritis patients. However the mechanisms of HOCl-induced cytotxicity are unknown. We determined the molecular mechanisms by which HOCl induced cell death in human mesenchymal progenitor cells (MPCs) differentiated into a chondrocytic phenotype as a model of human cartilage cells and show that HOCl induced rapid Bax conformational change, mitochondrial permeability and release of intra-mitochondrial pro-apoptotic proteins which resulted in nuclear translocation of AIF and EndoG. siRNA-mediated knockdown of Bax substantially prevented mitochondrial permeability, release of intra-mitochondrial pro-apoptotic proteins. Cell death was inhibited by siRNA-mediated knockdown of Bax, AIF or EndoG. Although we observed several biochemical markers of apoptosis, caspase activation was not detected either by western blotting, fluorescence activity assays or by using caspase inhibitors to inhibit cell death. This was further supported by findings that (1) in vitro exposure of recombinant human caspases to HOCl caused significant inhibition of caspase activity and (2) the addition of HOCl to staurosporine-treated MPCs inhibited the activity of cellular caspases. Our results show for the first time that HOCl induced Bax-dependent mitochondrial permeability which led to cell death without caspase activity by processes involving AIF/EndoG-dependent pathways. Our study provides a novel insight into the potential mechanisms of cell death in the inflamed human joint. (c) 2006 Elsevier Inc. All rights reserved.

Antitumour activity of [1,2-di(cyclopentadienyl)-1,2-di(p-N,N-dimethylaminophenyl)-ethanediyl] titanium dichloride in xenografted Ehrlich's ascites tumour

The effects of a new titanocene compound with an ansa ligand in the cyclopentadienyl rings, the 1,2-di(cyclopentadienyl)-1,2-di(p-NNdimethylaminophenyl)-ethanediyl] titanium dichloride (TITANOCENE X), on the growth and differentiation of granulocyte-macrophage progenitor cells [colony-forming unit-granulocyte-macrophage (CFU-GM)] and Natural killer (NK) cell activity in Ehrlich's ascites tumour (EAT)-bearing mice were studied. Myelosuppression concomitant with increased numbers of spleen CFU-GM was observed in tumour-bearing mice. Treatment of these animals with TITANOCENE X (2.5-50mg/kg/day) produced an increase in myelopoicsis, in a dose-dependent manner, and reduced spleen colony formation. In addition, the treatment of EAT-bearing mice with 3 doses of 20 or 50 mg/kg TITANOCENE X restored to normal values the reduced Natural killer cell function observed during tumour growth. In parallel, TITANOCENE X prolonged, in a dose-dependent manner, the survival of mice inoculated with Ehrlich's ascites tumour. The highest dose of 50 mg/kg prolonged in 50% the survival time of EAT-bearing mice, compared to non-treated tumour-bearing controls. In comparison with previous results from our laboratory addressing the effects of titanocenes on haematopoiesis, we observed with TITANOCENE X a similar effective profile as for bis(cyclopentadienyl) dithiocyanate titanium(IV), being both less effective than di(cyclopentadienyl) dichloro titanium(IV), since the latter not only prolonged, but also increased the rate of survival. These differences in efficacy may be due to the nature of the ansa-cyclopentadienyl ligand used in TITANOCENE X, since the C, bridge between the two cyclopentadienyl groups will increase the hydrolytic stability by an organometallic chelate effect. Also, the introduction of two dimethylamino substituents increases the water solubility of TITANOCENE X when compared to titanocene dichloride itself (c) 2006 Elsevier B.V. All rights reserved.

Adaptive divergence and speciation among sexual and pseudoviviparous populations of Festuca

Pseudovivipary is an environmentally induced flowering abnormality in which vegetative shoots replace seminiferous (sexual) inflorescences. Pseudovivipary is usually retained in transplantation experiments, indicating that the trait is not solely induced by the growing environment. Pseudovivipary is the defining characteristic of Festuca vivipara, and arguably the only feature separating this species from its closest seminiferous relative, Festuca ovina. We performed phylogenetic and population genetic analysis on sympatric F. ovina and F. vivipara samples to establish whether pseudovivipary is an adaptive trait that accurately defines the separation of genetically distinct Festuca species. Chloroplast and nuclear marker-based analyses revealed that variation at a geographical level can exceed that between F. vivipara and F. ovina. We deduced that F. vivipara is a recent species that frequently arises independently within F. ovina populations and has not accumulated significant genetic differentiation from its progenitor. We inferred local gene flow between the species. We identified one amplified fragment length polymorphism marker that may be linked to a pseudovivipary-related region of the genome, and several other markers provide evidence of regional local adaptation in Festuca populations. We conclude that F. vivipara can only be appropriately recognized as a morphologically and ecologically distinct species; it lacks genetic differentiation from its relatives. This is the first report of a ‘failure in normal flowering development’ that repeatedly appears to be adaptive, such that the trait responsible for species recognition constantly reappears on a local basis.

TRIM32 regulates skeletal muscle stem cell differentiation and is necessary for normal adult muscle regeneration

Limb girdle muscular dystrophy type 2H (LGMD2H) is an inherited autosomal recessive disease of skeletal muscle caused by a mutation in the TRIM32 gene. Currently its pathogenesis is entirely unclear. Typically the regeneration process of adult skeletal muscle during growth or following injury is controlled by a tissue specific stem cell population termed satellite cells. Given that TRIM32 regulates the fate of mammalian neural progenitor cells through controlling their differentiation, we asked whether TRIM32 could also be essential for the regulation of myogenic stem cells. Here we demonstrate for the first time that TRIM32 is expressed in the skeletal muscle stem cell lineage of adult mice, and that in the absence of TRIM32, myogenic differentiation is disrupted. Moreover, we show that the ubiquitin ligase TRIM32 controls this process through the regulation of c-Myc, a similar mechanism to that previously observed in neural progenitors. Importantly we show that loss of TRIM32 function induces a LGMD2H-like phenotype and strongly affects muscle regeneration in vivo. Our studies implicate that the loss of TRIM32 results in dysfunctional muscle stem cells which could contribute to the development of LGMD2H.

Persistence of a wild type Escherichia coli and its multiple antibiotic-resistant (MAR) derivatives in the abattoir and on chilled pig carcasses

The aim of this study was to evaluate the ability of an Escherichia coli with the multiple antibiotic resistance (MAR) phenotype to withstand the stresses of slaughter compared to an isogenic progenitor strain. A wild type E. coli isolate (345-2RifC) of porcine origin was used to derive 3 isogenic MAR mutants. Escherichia coli 345-2RifC and its MAR derivatives were inoculated into separate groups of pigs. Once colonisation was established, the pigs were slaughtered and persistence of the E. coli strains in the abattoir environment and on the pig carcasses was monitored and compared. No significant difference (P>0.05) was detected between the shedding of the different E. coli strains from the live pigs. Both the parent strain and its MAR derivatives persisted in the abattoir environment, however the parent strain was recovered from 6 of the 13 locations sampled while the MAR derivatives were recovered from 11 of 13 and the number of MAR E. coil recovered was 10-fold higher than the parent strain at half of the locations. The parent strain was not recovered from any of the 6 chilled carcasses whereas the MAR derivatives were recovered from 3 out of 5 (P<0.001). This study demonstrates that the expression of MAR in 345-2RifC increased its ability to survive the stresses of the slaughter and chilling processes. Therefore in E. coli, MAR can give a selective advantage, compared to non-MAR strains, for persistence on chilled carcasses thereby facilitating transit of these strains through the food chain. (C) 2010 Elsevier B.V. All rights reserved.

Fimbriae- and flagella-mediated association with and invasion of cultured epithelial cells by Salmonella enteritidis

Salmonella enteritidis expresses flagella and several finely regulated fimbriae, including SEF14, SEF17 and SEF21 (type 1). A panel of mutants was prepared in three strains of S. enteritidis to elucidate the role of these surface appendages in the association with and invasion of cultured epithelial cells. In all assays, the naturally occurring regulatory-defective strain 27655R associated with tissue culture cells significantly more than wild-type progenitor strains LA5 and S1400/94. Compared with wild-type strains, SEF14 mutants had no effect on association and invasion, whereas SEF17, SEF21 and aflagellate mutants showed significant reductions in both processes. Histological examination suggested a role for SEF17 in localized, aggregative adherence, which could be specifically blocked by anti-SEF17 sera and purified SEF17 fimbriae. SEF21-mediated association was neutralized by mannose and a specific monoclonal antibody, although to observe enhanced association it was necessary for the bacteria to be in fimbriate phase prior to infection. Additionally, aflagellate mutants associated and invaded less than motile bacteria. This study demonstrated the potential for multifactorial association and invasion of epithelial cells which involved SEF17 and SEF21 fimbriae, and flagella-mediated motility.