RESUMEN
El objetivo de esta investigación es presentar una adaptación y validación en población española de la Escala de Expectativa de los hijos adolescentes sobre la reacción de sus padres frente al comportamiento prosocial y antisocial, desarrollada por Wyatt y Carlo (2002). La muestra estuvo compuesta por 631 adolescentes españoles de entre 15 a 18 años de edad, de clase media, de ambos sexos. Se realizó un análisis factorial confirmatorio para estudiar la validez de constructo de la escala y se analizó la consistencia interna a través del cálculo del alpha de Cronbach. Los resultados indican que la escala posee buenos índices de ajuste al modelo teórico propuesto por los autores en su versión original. Asimismo, se realizó un análisis multigrupo con la intención de mostrar la invarianza del modelo en función del sexo. El modelo se mantuvo invariante, lo que confirma la estructura bifactorial de la escala que mide la expectativa de los adolescentes de la reacción de sus padres frente a las conductas adaptativas y desadaptativas.
The aim of this study is to carry out an adaptation and validation of Adolescents' Expected Parental Reactions Scale in Spanish sample. This original scale was developed by Wyatt and Carlo (2002). The sample was composed by 631 adolescents, between 15 and 18 years, middle-class and both sexes. A confirmatory factor analysis was carried out to study construct validity and with Cronbach's alpha was studied internal consistence. The results showed that scale has good fit indexes to theoretical model proposed by original authors. On the other hand, a multigroup analysis was carried out to study the invariance of model through both sexes. The model was invariant, this supports the bifactiral structure of the scale that assessments adolescents' expected parental reactions on prosocial and antisocial behaviors.
Asunto(s)
Psicología , Psicología SocialRESUMEN
STUDY DESIGN: Cross-sectional study with level III of evidence. OBJECTIVE: To describe different anthropometric and body composition parameters of adolescent girls with adolescent idiopathic scoliosis (AIS), comparing them with the standards of a healthy age-matched population. SUMMARY OF BACKGROUND DATA: Body growth and development of adolescent girls with AIS seems to differ from the healthy subjects, especially at perpubertal stages. Young scoliotic adults have been found to be taller, lighter, and thinner than age-matched healthy population. Body composition profile taken from measurements of skin-fold thickness, bony diameters at different levels, and arm and legs perimeters has not been previously reported in AIS patients. METHODS: A nonconsecutive series of 52 AIS girls (mean age: 13.9 years) with an average scoliotic curve of 27° Cobb (range: 20-58) underwent an anthropometric study. None of the AIS girls had been treated previously with spinal surgery. The control group consisted of 92 girls without spine deformity, matched in age (mean: 13.8 years). Weight, height, and skin-fold thickness in millimeters at six levels were measured. Body mass index (BMI), Ponderal index, percentage of body fat, percentage of muscular tissue, fat mass, lean body mass, muscular weight, bony weight, and residual weight were calculated using standard rules to estimate body composition. The somatotype components (endomorphy, mesomorphy, and ectomorphy) were calculated according to the Carter equations. RESULTS.: Compared with the control population, scoliotic girls had a significantly lower mean weight (51.4 ± 10.2 kg vs. 54.7 ± 8.1 kg; P < 0,05), a lower BMI (20.1 ± 3.4 vs. 21.4 ± 2.4; P < 0.001), and a higher Ponderal index (43.2 ± 2.4 vs. 42.2 ± 1.6; P < 0.01). Girls with AIS showed a progressive decrease of the BMI as the age increased. The percentage of body fat was also lower in scoliotic girls, without significant statistical differences (14.1 ± 3.8 vs. 15 ± 3.6). Out of the 52 AIS girls, 11 (21.2%) showed a BMI below 17.5, which has been considered the limit for anorexia. In the control group, only 3 of 92 girls (3.3%) had BMI below that level. The somatotype differed also between scoliotics and controls: higher in the ectomorphic component (3.29 ± 1.68 vs. 2.40 ± 1.11; P < 0.001), and lower in the mesomorphic component (2.86 ± 0.82 vs. 3.70 ± 1.11; P < 0.01) in AIS patients. CONCLUSION: The differences in some anthropometric parameters (weight, IMC, IP) and in the somatotype suggest that the idiopathic scoliosis not only disturbs normal spine growth but also seems to have implications on the whole corporal development. Whether these changes could be related to abnormal spinal growth or subsequent to nutritional changes in AIS still remains uncertain. Presumably, some endocrine factors affecting body composition and growth might be involved in the etiology of idiopathic scoliosis.
Asunto(s)
Estatura/fisiología , Índice de Masa Corporal , Peso Corporal/fisiología , Escoliosis/fisiopatología , Adolescente , Antropometría/métodos , Composición Corporal/fisiología , Estudios Transversales , Femenino , Humanos , Análisis de Regresión , Escoliosis/patología , Adulto JovenRESUMEN
The transcriptional factor Snail1 is a repressor of E-cadherin (CDH1) gene expression essential for triggering epithelial-mesenchymal transition. Snail1 represses CDH1, directly binding its promoter and inducing the synthesis of the Zeb1 repressor. In this article, we show that repression of CDH1 by Snail1, but not by Zeb1, is dependent on the activity of Polycomb repressive complex 2 (PRC2). Embryonic stem (ES) cells null for Suz12, one of the components of PRC2, show higher levels of Cdh1 mRNA than control ES cells. In tumor cells, interference of PRC2 activity prevents the ability of Snail1 to downregulate CDH1 and partially derepresses CDH1. Chromatin immunoprecipitation assays demonstrated that Snail1 increases the binding of Suz12 to the CDH1 promoter and the trimethylation of lysine 27 in histone H3. Moreover, Snail1 interacts with Suz12 and Ezh2, as shown by coimmunoprecipitation experiments. In conclusion, these results demonstrate that Snail1 recruits PRC2 to the CDH1 promoter and requires the activity of this complex to repress E-cadherin expression.
Asunto(s)
Cadherinas/metabolismo , Proteínas Represoras/metabolismo , Factores de Transcripción/metabolismo , Animales , Sitios de Unión , Cadherinas/genética , Línea Celular , Línea Celular Tumoral , Regulación hacia Abajo , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Mesodermo/citología , Mesodermo/metabolismo , Ratones , Complejo Represivo Polycomb 2 , Proteínas del Grupo Polycomb , Regiones Promotoras Genéticas/genética , Unión Proteica , Estructura Terciaria de Proteína , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción de la Familia Snail , Factores de Transcripción/químicaRESUMEN
E-cadherin and its transcriptional repressor Snail1 (Snai1) are two factors that control epithelial phenotype. Expression of Snail1 promotes the conversion of epithelial cells to mesenchymal cells, and occurs concomitantly with the downregulation of E-cadherin and the upregulation of expression of mesenchymal genes such as those encoding fibronectin and LEF1. We studied the molecular mechanism controlling the expression of these genes in mesenchymal cells. Forced expression of E-cadherin strongly downregulated fibronectin and LEF1 RNA levels, indicating that E-cadherin-sensitive factors are involved in the transcription of these genes. E-cadherin overexpression decreased the transcriptional activity of the fibronectin promoter and reduced the interaction of beta-catenin and NF-kappaB with this promoter. Similar to beta-catenin, NF-kappaB was found, by co-immunoprecipitation and pull-down assays, to be associated with E-cadherin and other cell-adhesion components. Interaction of the NF-kappaB p65 subunit with E-cadherin or beta-catenin was reduced when adherens junctions were disrupted by K-ras overexpression or by E-cadherin depletion using siRNA. These conditions did not affect the association of p65 with the NF-kappaB inhibitor IkappaBalpha. The functional significance of these results was stressed by the stimulation of NF-kappaB transcriptional activity, both basal and TNF-alpha-stimulated, induced by an E-cadherin siRNA. Therefore, these results demonstrate that E-cadherin not only controls the transcriptional activity of beta-catenin but also that of NF-kappaB. They indicate too that binding of this latter factor to the adherens junctional complex prevents the transcription of mesenchymal genes.
Asunto(s)
Cadherinas/genética , Fibronectinas/genética , Regulación de la Expresión Génica , Factor de Unión 1 al Potenciador Linfoide/genética , FN-kappa B/genética , Transcripción Genética , beta Catenina/genética , Cadherinas/metabolismo , Línea Celular , Fibronectinas/metabolismo , Humanos , Factor de Unión 1 al Potenciador Linfoide/metabolismo , Mesodermo/metabolismo , FN-kappa B/metabolismo , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , beta Catenina/metabolismoRESUMEN
The product of the Snail1 gene is a transcriptional repressor required for triggering the epithelial-to-mesenchymal transition. Furthermore, ectopic expression of Snail1 in epithelial cells promotes resistance to apoptosis. In this study, we demonstrate that this resistance to gamma radiation-induced apoptosis caused by Snail1 is associated with the inhibition of PTEN phosphatase. In MDCK cells, mRNA levels of the p53 target gene PTEN are induced after gamma radiation; the transfection of Snail1 prevents this up-regulation. Decreased mRNA levels of PTEN were also detected in RWP-1 cells after the ectopic expression of this transcriptional factor. Snail1 represses and associates to the PTEN promoter as detected both by the electrophoretic mobility shift assay and chromatin immunoprecipitation experiments performed with either endogenous or ectopic Snail1. The binding of Snail1 to the PTEN promoter increases after gamma radiation, correlating with the stabilization of Snail1 protein, and prevents the association of p53 to the PTEN promoter. These results stress the critical role of Snail1 in the control of apoptosis and demonstrate the regulation of PTEN phosphatase by this transcriptional repressor.
Asunto(s)
Apoptosis/efectos de la radiación , Rayos gamma , Regulación de la Expresión Génica , Fosfohidrolasa PTEN/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Daño del ADN , ADN Complementario , Perros , Fase G2 , Genes Reporteros , Humanos , Luciferasas de Luciérnaga/análisis , Luciferasas de Luciérnaga/metabolismo , Luciferasas de Renilla/análisis , Luciferasas de Renilla/metabolismo , Sustancias Luminiscentes/metabolismo , Neoplasias Pancreáticas/patología , Regiones Promotoras Genéticas , Inhibidores de la Síntesis de la Proteína/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Puromicina/farmacología , ARN Mensajero/metabolismo , ARN Interferente Pequeño/farmacología , Selección Genética , Factores de Transcripción de la Familia Snail , Factores de Tiempo , Factores de Transcripción/genética , Factores de Transcripción/farmacología , TransfecciónRESUMEN
The product of Snail1 gene is a transcriptional repressor of E-cadherin expression and an inductor of the epithelial-mesenchymal transition in several epithelial tumour cell lines. Transcription of Snail1 is induced when epithelial cells are forced to acquire a mesenchymal phenotype. In this work we demonstrate that Snail1 protein limits its own expression: Snail1 binds to an E-box present in its promoter (at -146 with respect to the transcription start) and represses its activity. Therefore, mutation of the E-box increases Snail1 transcription in epithelial and mesenchymal cells. Evidence of binding of ectopic or endogenous Snail1 to its own promoter was obtained by chromatin immunoprecipitation (ChIP) experiments. Studies performed expressing different forms of Snail1 under the control of its own promoter demonstrate that disruption of the regulatory loop increases the cellular levels of Snail protein. These results indicate that expression of Snail1 gene can be regulated by its product and evidence the existence of a fine-tuning feed-back mechanism of regulation of Snail1 transcription.
Asunto(s)
Elementos E-Box , Regulación de la Expresión Génica , Regiones Promotoras Genéticas , Proteínas Represoras/genética , Factores de Transcripción/genética , Animales , Sitios de Unión , Línea Celular , Regulación hacia Abajo , Homeostasis , Humanos , Ratones , ARN Mensajero/metabolismo , Proteínas Represoras/metabolismo , Factores de Transcripción de la Familia Snail , Factores de Transcripción/metabolismoRESUMEN
Myotonia is a condition characterized by impaired relaxation of muscle following sudden forceful contraction. We systematically screened all 23 exons of the CLCN1 gene in 88 unrelated patients with myotonia and identified mutations in 14 patients. Six novel mutations were discovered: five were missense (S132C, L283F, T310M, F428S and T550M) found in heterozygous patients, and one was a nonsense mutation (E193X) in a homozygous patient. While five patients had a clinical diagnosis of myotonia congenita, the patient with the F428S mutation exhibited symptoms characteristic of paramyotonia congenita--a condition usually thought to be caused by mutations in the sodium channel gene SCN4A. Nevertheless, no mutations in SCN4A were identified in this patient. The functional consequences of the novel CLCN1 sequence variants were explored by recording chloride currents from human embryonic kidney cells transiently expressing homo- or heterodimeric mutant channels. The five tested mutations caused distinct functional alterations of the homodimeric human muscle chloride ion channel hClC-1. S132C and T550M conferred novel hyperpolarization-induced gating steps, L283F and T310M caused a shift of the activation curve to more positive potentials and F428S reduced the expression level of hClC-1 channels. All showed a dominant-negative effect. For S132C, L283F, T310M and T550M, heterodimeric channels consisting of one wild-type (WT) and one mutant subunit exhibited a shifted activation curve at low intracellular [Cl(-)]. WT-F428S channels displayed properties similar to WT hClC-1, but expressed at significantly lower levels. The novel mutations exhibit a broad variety of functional defects that, by distinct mechanisms, cause a significant reduction of the resting chloride conductance in muscle of heterozygous patients. Our results provide novel insights into functional alterations and clinical symptoms caused by mutations in CLCN1.
Asunto(s)
Canales de Cloruro/deficiencia , Músculo Esquelético/metabolismo , Mutación/genética , Miotonía Congénita/genética , Adulto , Empalme Alternativo/genética , Secuencia de Aminoácidos/genética , Membrana Celular/genética , Membrana Celular/metabolismo , Canales de Cloruro/genética , Análisis Mutacional de ADN , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Mutación Missense/genética , Miotonía Congénita/metabolismo , Miotonía Congénita/fisiopatologíaRESUMEN
Mutations in the muscle chloride channel gene CLCN1 cause myotonia congenita, an inherited disorder of skeletal muscle excitability leading to a delayed relaxation after muscle contraction. Here, we examine the functional consequences of a novel disease-causing mutation that predicts the substitution of alanine by threonine at position 331 (A331T) by whole-cell patch-clamp recording of recombinant mutant channels. A331T hClC-1 channels exhibit a novel slow gate that activates during membrane hyperpolarization and closes at positive potentials. This novel gate acts in series with fast opening and closing transitions that are common to wild-type (WT) and mutant channels. Under conditions at which this novel gate is not activated, i.e., a holding potential of 0 mV, the typical depolarization-induced activation gating of WT hClC-1 was only slightly affected by the mutation. In contrast, A331T hClC-1 channels with an open slow gate display an altered voltage dependence of open probability. These novel gating features of mutant channels produce a decreased open probability at -85 mV, the normal muscle resting potential, leading to a reduced resting chloride conductance of affected muscle fibers. The A331T mutation causes an unprecedented alteration of ClC-1 gating and reveals novel processes defining transitions between open and closed states in ClC chloride channels.