Smc5/6 coordinates formation and resolution of joint molecules with chromosome morphology to ensure meiotic divisions

During meiosis, Structural Maintenance of Chromosome (SMC) complexes underpin two fundamental features of meiosis: homologous recombination and chromosome segregation. While meiotic functions of the cohesin and condensin complexes have been delineated, the role of the third SMC complex, Smc5/6, remains enigmatic. Here we identify specific, essential meiotic functions for the Smc5/6 complex in homologous recombination and the regulation of cohesin. We show that Smc5/6 is enriched at centromeres and cohesin-association sites where it regulates sister-chromatid cohesion and the timely removal of cohesin from chromosomal arms, respectively. Smc5/6 also localizes to recombination hotspots, where it promotes normal formation and resolution of a subset of joint-molecule intermediates. In this regard, Smc5/6 functions independently of the major crossover pathway defined by the MutLγ complex. Furthermore, we show that Smc5/6 is required for stable chromosomal localization of the XPF-family endonuclease, Mus81-Mms4Eme1. Our data suggest that the Smc5/6 complex is required for specific recombination and chromosomal processes throughout meiosis and that in its absence, attempts at cell division with unresolved joint molecules and residual cohesin lead to severe recombination-induced meiotic catastroph

Tipologia das perguntas sobre variabilidade nos livros escolares e sua relação com alfabetização e pensamento estatístico

and thinking among students in the school system. [Methodology] To achieve this objective, a qualitative approach was used based on a content analysis of the secondary education textbooks published in the years 2016, 2018, 2020 and 2021. Units of analysis were selected using non-probabilistic subjective sampling. [Results] Among the most relevant findings, it was determined that a large part of the questions in the textbooks consulted made use of the interrogative pronouns “what” and “which.” In these cases, the questions were associated with simple tasks aimed essentially at the calculation of descriptive summaries of variability without the use of technological tools. On the other hand, questions related to more complex tasks such as reading, analyzing and making decisions, were poorly represented in the textbooks analyzed. The concept of variability in the textbooks consulted is fundamentally related to the notion of dispersion, an approach that has been questioned by English-speaking researchers. [Conclusions] In brief, based on the results obtained it is recommended that teachers in the school system guide, reformulate and design questions related to the concept of variability based in more complex activities such as analysis, argumentation and evaluation to better assist students in developing statistical literacy and thinking.  [Objetivo] El presente estudio tiene como propósito analizar si las preguntas relacionadas con el concepto de variabilidad que se presentan en los textos escolares de enseñanza secundaria en Chile permiten alfabetizar y pensar estadísticamente a los estudiantes del sistema escolar. [Metodología] Para tal efecto se hizo uso de un enfoque cualitativo mediante un análisis de contenido de los libros de textos de enseñanza secundaria publicados en los años 2016-2018-2020 y 2021. Las unidades de análisis fueron seleccionadas mediante un muestreo no probabilístico del tipo intencionado. [Resultados] Entre los hallazgos más relevantes se puede señalar que gran parte de las preguntas de los libros de texto analizados hacen uso de pronombres interrogativos qué y cuál. En estos casos, la interrogante se asocia a interpelaciones de bajo nivel cognitivo destinadas esencialmente al cálculo de estadígrafos de variabilidad, sin hacer uso de herramientas tecnología. Por el contrario, las preguntas afines a niveles cognitivos superiores como leer, analizar y tomar decisiones evidencian baja representatividad dentro de los casos observados. El concepto variabilidad se relaciona de manera fundamental con la noción de dispersión, lo cual ha sido cuestionado por investigadores de habla inglesa. [Conclusiones] En síntesis, los resultados sugieren que es recomendable que los profesores del sistema escolar orienten, reformulen y diseñen preguntas afines al concepto de variabilidad tomando como base las preguntas clasificadas en categorías superiores tales como análisis, argumentación y evaluación de manera que el estudiantado desarrolle una alfabetización y pensamiento estadísticovariabilidade apresentada nos livros didáticos do ensino médio no Chile permitem que os alunos do sistema escolar aprendam alfabetização e pensem estatisticamente. [Metodologia] Para isso, foi utilizada uma abordagem qualitativa por meio de análise de conteúdo de livros didáticos do ensino médio publicados nos anos 2016-2018-2020 e 2021. As unidades de análise foram selecionadas por amostragem não probabilística do tipo intencional. [Resultados] Entre as descobertas mais relevantes, pode-se notar que grande parte das perguntas nos livros didáticos analisados fazem uso de pronomes interrogativos: o que e qual. Nesses casos, a questão está associada a interpelações de baixo nível cognitivo voltadas essencialmente para o cálculo das estatísticas de variabilidade, sem fazer uso de ferramentas tecnológicas. Pelo contrário, as perguntas relacionadas a níveis cognitivos mais elevados, como leitura, análise e tomada de decisões, apresentam baixa representatividade dentro dos casos observados. O conceito de variabilidade está fundamentalmente relacionado à noção de dispersão, que tem sido questionada por pesquisadores de língua inglesa. [Conclusões] Em resumo, os resultados sugerem que é recomendável os professores do sistema escolar guiarem, reformularem e projetarem perguntas relacionadas ao conceito de variabilidade com base em perguntas classificadas em categorias superiores, como análise, argumentação e avaliação para que os alunos desenvolvam alfabetização e pensamento estatístico.    &nbsp

PERCEPCION DE RIESGO LABORAL DE LAS ENFERMERAS DE UNA UNIDAD DE CUIDADO INTENSIVO

The purpose of this exploratory descriptive study was to determine nurses zs perception about their working environment in an intensive care unit in a hospital, through the application of a questionnaire containing closed and open ended questions. It was intended to determine the work environment risks and the preventive actions used to elimínate such risks.As the results were known, we learned that the most of the nurses consider their labor environment as confortable and cozy one; nevertheless, potential environment risks are perceived, principally the exposure to Chemical, physical, biologic and mechanical risks, associated to the lack of material and human resources as well as the lack of awareness among the nurses as far as the use of individual protection elements is concerned.Estudio de tipo descriptivo exploratorio cuyo objetivo fue describir las opiniones de las enfermeras de una Unidad de Cuidado Intensivo hospitalaria sobre su ambiente de trabajo a través de la aplicación de un cuestionario, conteniendo preguntas abiertas y cerradas donde se procuró detectar los riesgos del ambiente de trabajo y las medidas preventivas utilizadas para eliminar tales riesgos.Con los resultados obtenidos constatamos que la mayoría de las enfermeras encuentran su ambiente de trabajo confortable; no obstante, perciben riesgos ambientales potenciales principalmente la exposición a riesgos químicos, físicos, biológicos y mecánicos, asociados a la falta de recursos humanos y materiales, y a la falta de conciencia de las enfermeras en el uso de los elementos protectores individuales

Design and study of psychometric properties of the community attitude to abortion scale (caas) with the chilean population: autonomy and stigma

This study is part of the project FONDECYT/No.11180588. This work was funded by the European Regional Development Funds (European Union and Principality of Asturias) through the Science, Technology, and Innovation Plan (AYUD/2021/51411)

Mortality After Pediatric Arterial Ischemic Stroke

OBJECTIVES: Cerebrovascular disease is among the top 10 causes of death in US children, but risk factors for mortality are poorly understood. Within an international registry, we identify predictors of in-hospital mortality after pediatric arterial ischemic stroke (AIS). METHODS: Neonates (0-28 days) and children (29 days- < 19 years) with AIS were enrolled from January 2003 to July 2014 in a multinational stroke registry. Death during hospitalization and cause of death were ascertained from medical records. Logistic regression was used to analyze associations between risk factors and in-hospital mortality. RESULTS: Fourteen of 915 neonates (1.5%) and 70 of 2273 children (3.1%) died during hospitalization. Of 48 cases with reported causes of death, 31 (64.6%) were strokerelated, with remaining deaths attributed to medical disease. In multivariable analysis, congenital heart disease (odds ratio [OR]: 3.88; 95% confidence interval [CI] : 1.23-12.29; P = .021), posterior plus anterior circulation stroke (OR: 5.36; 95% CI: 1.70-16.85; P = .004), and stroke presentation without seizures (OR: 3.95; 95% CI: 1.26-12.37; P = .019) were associated with in-hospital mortality for neonates. Hispanic ethnicity (OR: 3.12; 95% CI: 1.56-6.24; P = .001), congenital heart disease (OR: 3.14; 95% CI: 1.75-5.61; P < .001), and posterior plus anterior circulation stroke (OR: 2.71; 95% CI: 1.40-5.25; P = .003) were associated with in-hospital mortality for children. CONCLUSIONS: In-hospital mortality occurred in 2.6% of pediatric AIS cases. Most deaths were attributable to stroke. Risk factors for in-hospital mortality included congenital heart disease and posterior plus anterior circulation stroke. Presentation without seizures and Hispanic ethnicity were also associated with mortality for neonates and children, respectively. Awareness and study of risk factors for mortality represent opportunities to increase survival

Checkpoint kinase1 (CHK1) is an important biomarker in breast cancer having a role in chemotherapy response

Background:Checkpoint kinase1 (CHK1), which is a key component of DNA-damage-activated checkpoint signalling response, may have a role in breast cancer (BC) pathogenesis and influence response to chemotherapy. This study investigated the clinicopathological significance of phosphorylated CHK1 (pCHK1) protein in BC.Method:pCHK1 protein expression was assessed using immunohistochemistry in a large, well-characterized annotated series of early-stage primary operable invasive BC prepared as tissue microarray (n=1200).Result:pCHK1 showed nuclear and/or cytoplasmic expression. Tumours with nuclear expression showed positive associations with favourable prognostic features such as lower grade, lower mitotic activity, expression of hormone receptor and lack of expression of KI67 and PI3K (

Tipología de las preguntas sobre variabilidad en los textos escolares y su relación con la alfabetización y pensamiento estadístico

[Objetivo] El presente estudio tiene como propósito analizar si las preguntas relacionadas con el concepto de variabilidad que se presentan en los textos escolares de enseñanza secundaria en Chile permiten alfabetizar y pensar estadísticamente a los estudiantes del sistema escolar. [Metodología] Para tal efecto se hizo uso de un enfoque cualitativo mediante un análisis de contenido de los libros de textos de enseñanza secundaria publicados en los años 2016-2018-2020 y 2021. Las unidades de análisis fueron seleccionadas mediante un muestreo no probabilístico del tipo intencionado. [Resultados] Entre los hallazgos más relevantes se puede señalar que gran parte de las preguntas de los libros de texto analizados hacen uso de pronombres interrogativos qué y cuál. En estos casos, la interrogante se asocia a interpelaciones de bajo nivel cognitivo destinadas esencialmente al cálculo de estadígrafos de variabilidad, sin hacer uso de herramientas tecnología. Por el contrario, las preguntas afines a niveles cognitivos superiores como leer, analizar y tomar decisiones evidencian baja representatividad dentro de los casos observados. El concepto variabilidad se relaciona de manera fundamental con la noción de dispersión, lo cual ha sido cuestionado por investigadores de habla inglesa. [Conclusiones] En síntesis, los resultados sugieren que es recomendable que los profesores del sistema escolar orienten, reformulen y diseñen preguntas afines al concepto de variabilidad tomando como base las preguntas clasificadas en categorías superiores tales como análisis, argumentación y evaluación de manera que el estudiantado desarrolle una alfabetización y pensamiento estadístico</jats:p