La Danza y Expresión Corporal es una disciplina científica que ha evolucionado en los últimos años desde el estudio del movimiento per se hacia el análisis del cuerpo y de la danza en todas sus ...dimensiones. De esta forma, se ha configurado un cuerpo de conocimientos con gran base empírica, del cual se nutren áreas como la Medicina, Psicología, Pedagogía, y resto de ciencias relacionadas con la actividad física y el deporte. Para entender esta evolución, es fundamental hacer una diferenciación entre el concepto de Danza y el concepto de Expresión Corporal, hacer un recorrido por su objeto de estudio y por su status científico, incidiendo en las tres dimensiones principales donde se orientan sus aportes: la dimensión artística, la dimensión pedagógica y la dimensión psicoterapéutica. Por tanto, dada la importancia de esta materia para aumentar el cuerpo de conocimientos dentro de las Ciencias de la Actividad Física y del Deporte, es necesario profundizar en sus fundamentos epistemológicos para orientar futuros estudios.Abstract. Dance and Body Expression is a scientific discipline that has evolved in recent years from the study of movement per se towards the analysis of the body and dance in all its dimensions. In this way, a body of knowledge has been configured with a great empirical base, from which areas such as Medicine, Psychology, Pedagogy, and other sciences related to physical activity and sport are nourished. To understand this evolution, it is essential to make a differentiation between the concept of Dance and the concept of Body Expression, and to take a tour of its object of study and its scientific status, focusing on the three main dimensions where its contributions are oriented: artistic dimension, pedagogical dimension and psychotherapeutic dimension. Therefore, given the importance of this subject to increase the body of knowledge within Physical Activity and Sport Sciences, it is necessary to deepen in its epistemological foundations to guide future studies.
The versatility of epithelial stem cells
Stem cells are very important in the maintenance of our bodies' tissues and organs. Blanpain and Fuchs review how different populations of naturally ...lineage-restricted epithelial stem cells and committed progenitors can also display remarkable plasticity. These cells can reacquire long-term self-renewing capacities and multilineage differentiation potential during physiological and regenerative conditions. These abilities depend on whether the stem cell remains within its resident niche or has been mobilized to repair a wound. Such cellular plasticity has implications for regenerative medicine and for cancer.
Science
, this issue p.
10.1126/science.1242281
Tissues rely upon stem cells for homeostasis and repair. Recent studies show that the fate and multilineage potential of epithelial stem cells can change depending on whether a stem cell exists within its resident niche and responds to normal tissue homeostasis, whether it is mobilized to repair a wound, or whether it is taken from its niche and challenged to de novo tissue morphogenesis after transplantation. In this Review, we discuss how different populations of naturally lineage-restricted stem cells and committed progenitors can display remarkable plasticity and reversibility and reacquire long-term self-renewing capacities and multilineage differentiation potential during physiological and regenerative conditions. We also discuss the implications of cellular plasticity for regenerative medicine and for cancer.
Most educators want to provide appropriate instruction for the diverse learning needs of their students, however moving from theory to practice can stymie both novice and experienced teachers. The ...author shows middle- and secondary-level teachers how to plan a differentiated lesson from start to finish, detailing the steps to take before, during, and after to deepen connections for students. At each stage, the book offers tested strategies and reflective advice about reaching a wide range of learners within the same classroom. Annotated models of effective differentiated instruction, including tiering, flexible groupings, and adjustments based on formative assessments, are included. Through interdisciplinary examples, these processes can be extended to any subject. Contents include Foreword (Carol Ann Tomlinson) and five chapters: (1) Developing a Common Frame of Reference; (2) A Walk-Through of a Differentiated Lesson; (3) Helpful Structures and Strategies for the Differentiated Class; (4) Cognitive Structures and Tips That Help Us Differentiate; and (5) Twelve Samples of Differentiated Learning Experiences from Multiple Subjects. The book concludes with A Final Word: Three Tips to Begin the Journey, recommended resources, an appendix and references. An index is included.
Chromatin state dynamics during blood formation Lara-Astiaso, David; Weiner, Assaf; Lorenzo-Vivas, Erika ...
Science (American Association for the Advancement of Science),
08/2014, Volume:
345, Issue:
6199
Journal Article
Peer reviewed
Open access
Chromatin modifications are crucial for development, yet little is known about their dynamics during differentiation. Hematopoiesis provides a well-defined model to study chromatin state dynamics; ...however, technical limitations impede profiling of homogeneous differentiation intermediates. We developed a high-sensitivity indexing-first chromatin immunoprecipitation approach to profile the dynamics of four chromatin modifications across 16 stages of hematopoietic differentiation. We identify 48,415 enhancer regions and characterize their dynamics. We find that lineage commitment involves de novo establishment of 17,035 lineage-specific enhancers. These enhancer repertoire expansions foreshadow transcriptional programs in differentiated cells. Combining our enhancer catalog with gene expression profiles, we elucidate the transcription factor network controlling chromatin dynamics and lineage specification in hematopoiesis. Together, our results provide a comprehensive model of chromatin dynamics during development.
Human genetic history in East Asia is poorly understood. To clarify population relationships, we obtained genome wide data from 26 ancient individuals from northern and southern East Asia spanning ...9,500-300 years ago. Genetic differentiation was higher in the past than the present, reflecting a major episode of admixture involving northern East Asian ancestry spreading across southern East Asia after the Neolithic, transforming the genetic ancestry of southern China. Mainland southern East Asian and Taiwan Strait island samples from the Neolithic show clear connections with modern and ancient samples with Austronesian-related ancestry, supporting a southern China origin for proto-Austronesians. Connections among Neolithic coastal groups from Siberia and Japan to Vietnam indicate that migration and gene flow played an important role in the prehistory of coastal Asia.
On being the right (cell) size Ginzberg, Miriam B.; Kafri, Ran; Krischner, Marc
Science (American Association for the Advancement of Science),
05/2015, Volume:
348, Issue:
6236
Journal Article
Peer reviewed
Open access
How cells know when they are the right size
Biologists have long recognized that cells exist in a large range of sizes. Cell size is also flexible: Cells can differentiate into another cell type with ...a very different size. External factors can also influence cell size, but the consistent size of a given cell type shows that cells have mechanisms to measure their own size and adjust their growth rate or rate of cell division to maintain uniformity. Ginzberg
et al.
review recent advances in understanding how cells know when they are at the right size.
Science
, this issue
10.1126/science.1245075
BACKGROUND
How do the different cell types in our bodies maintain their distinctive and characteristic sizes? Although much is known about the signaling networks that stimulate or suppress cell growth, such as the mammalian target of rapamycin (mTOR) pathway, this central question remains: How do a common set of pathways precisely specify the appropriate size for any given cell type and physiological condition? The precision with which size is controlled is demonstrated by the uniformity in cell size typically seen in tissues. Most epithelial tissues, for example, display a striking regularity in the size and morphology of cells, whereas size heterogeneity can be a sign of neoplastic growth.
Most work on the subject of how cell size is regulated has explored the control of cell growth and proliferation by extracellular signals, such as growth factors and cytokines. However, although these signals can dictate the mean size of cells, individual cells will inevitably deviate from that mean. Variability in cell size can arise from variability in growth rate and cell-cycle length or asymmetry in cell division. These sources of variation raise the question of whether they are counteracted by cellular mechanisms that act to increase size homogeneity. Size variation can only be reduced with processes that differentially affect cells of different sizes, despite the fact that they share the same environment. This kind of control requires that individual cells measure their own size and adjust their behavior as necessary to achieve a common target size.
ADVANCES
In this Review, we present a growing body of evidence that suggests that animal cells autonomously measure and adjust their individual sizes to maintain uniformity within a population. We discuss possible mechanisms by which this can be achieved, including the size-dependent adjustment of cell-cycle length and/or growth rate, as well as the limitations of these strategies. We summarize the progress that has been made thus far in identifying the cell’s size control machinery and highlight important unanswered questions.
The presence of mechanisms ensuring precise size specification suggests that there may be an optimal cell size for a particular cell’s function. Here, we address the question of whether cells function most efficiently when at the “right” size by examining cases in which cell size was altered naturally or experimentally. Some tissues seem to easily compensate for cell-size changes, whereas in others, cells appear to perform best at their appropriate size. We highlight examples of cell types, such as pancreatic β cells and adipocytes, in which a relationship between cell size and cell function has been observed.
OUTLOOK
We conclude by discussing the gaps in our understanding of how cell size is regulated, stressing the questions that have been most neglected. Throughout this Review, we point out the experimental challenges that have hindered progress in this field and emphasize recent technological advances that may allow us to overcome these obstacles. Last, we pose the questions that we anticipate will guide this field in the upcoming years.
How is cell size specified?
(
Left
) In populations of proliferating cells, size uniformity may be ensured by linking the processes of growth and cell-cycle progression. One way this can be accomplished is by restricting progress through a particular cell-cycle stage (for example, the G
1
/S transition) to cells that have reached a specific “target” size. (
Right
) Typical sizes of various human cell types. Cells are drawn to scale: pancreatic β cells, hepatocytes, keratinocytes, fibroblasts, and adipocytes.
ILLUSTRATION CREDIT: K. SUTLIFF/
SCIENCE
Different animal cell types have distinctive and characteristic sizes. How a particular cell size is specified by differentiation programs and physiology remains one of the fundamental unknowns in cell biology. In this Review, we explore the evidence that individual cells autonomously sense and specify their own size. We discuss possible mechanisms by which size-sensing and size-specification may take place. Last, we explore the physiological implications of size control: Why is it important that particular cell types maintain a particular size? We develop these questions through examination of the current literature and pose the questions that we anticipate will guide this field in the upcoming years.
Innate lymphoid cells: A new paradigm in immunology Eberl, Gérard; Colonna, Marco; Di Santo, James P. ...
Science (American Association for the Advancement of Science),
05/2015, Volume:
348, Issue:
6237
Journal Article
Peer reviewed
Open access
Cells acting at the intersection of immunityFor years, scientists divided the immune system into two arms: innate and adaptive. The cell types involved in the two arms differ in specificity and in ...how quickly they respond to infections. More recently, immunologists discovered a family of immune cells termed "innate lymphoid cells," which straddle these two arms. Eberl et al. review current understanding of innate lymphoid cells. Like innate immune cells, they respond to infection quickly and do not express antigen receptors; however, they secrete a similar suite of inflammatory mediators as T lymphocytes. Better understanding of the processes regulating these cells may allow for their therapeutic manipulation.Science, this issue 10.1126/science.aaa6566 Innate lymphoid cells (ILCs) are a growing family of immune cells that mirror the phenotypes and functions of T cells. However, in contrast to T cells, ILCs do not express acquired antigen receptors or undergo clonal selection and expansion when stimulated. Instead, ILCs react promptly to signals from infected or injured tissues and produce an array of secreted proteins termed cytokines that direct the developing immune response into one that is adapted to the original insult. The complex cross-talk between microenvironment, ILCs, and adaptive immunity remains to be fully deciphered. Only by understanding these complex regulatory networks can the power of ILCs be controlled or unleashed in order to regulate or enhance immune responses in disease prevention and therapy.
Performing Mathematical Operations with Metamaterials Silva, Alexandre; Monticone, Francesco; Castaldi, Giuseppe ...
Science (American Association for the Advancement of Science),
01/2014, Volume:
343, Issue:
6167
Journal Article
Peer reviewed
We introduce the concept of metamaterial analog computing, based on suitably designed metamaterial blocks that can perform mathematical operations (such as spatial differentiation, integration, or ...convolution) on the profile of an impinging wave as it propagates through these blocks. Two approaches are presented to achieve such functionality: (i) subwavelength structured metascreens combined with graded-index waveguides and (ii) multilayered slabs designed to achieve a desired spatial Green's function. Both techniques offer the possibility of miniaturized, potentially integrable, wave-based computing systems that are thinner than conventional lens-based optical signal and data processors by several orders of magnitude.
IntroductionLeigh Syndrome is a rare progressive neurometabolic disorder. Perinatal onset has been previously reported. Very few of these infants have been reported to be encephalopathic at birth. ...Differentiation between hypoxic ischaemic encephalopathy and perinatal Leigh disease can be difficult as the clinical presentation and radiological findings can be similar.CaseReport A male infant was delivered at 38+6 weeks, weighing 3060g by emergency caesarean section due to persistent fetal tachycardia with reduced variability. He was the first child of healthy non-consanguineous parents. He was mechanically ventilated at birth due to lack of spontaneous breathing but did not need any other resuscitation. He was severely encephalopathic since birth and received therapeutically hypothermia for 72 h. He had severe lactic acidosis which responded to Na-dichloroacetate. Cerebral function monitoring showed burst suppression pattern with severely suppressed trace and showed no recovery following hypothermia. Electroencephalogram showed extremely low amplitude suggestive of severe cortical dysfunction. MRI brain on day 8 revealed bilateral symmetrical focal signal changes involving the basal ganglion, internal capsule, brainstem and perirolandic region; features favouring profound hypoxic-ischaemic insult. He continued to remain severely encephalopathic disproportionate to the hypoxia sustained at birth, raising the suspicion of a metabolic condition. All metabolic investigations and muscle respiratory chain enzymes were normal. Muscle biopsy showed immature muscle with scattered fibres containing increased lipid. MTO1 and RMND1 genetic analysis was normal. Due to lack of clinical improvement, intensive care was discontinued on day 11 leading to his demise. The post-mortem neuro-histology showed chronic grey and white matter damage with neuronal calcification, microglial response, glial scars, capillary response, cyst formation and most importantly, relative neuronal preservation in necrotic foci (the latter not usually seen in hypoxic encephalopathy) confirming Leigh disease.ConclusionEncephalopathy at birth in absence of clear history of perinatal hypoxia should prompt consideration of wider differential diagnosis of possible neuro-metabolic cause. The differentiation is important for subsequent management, prognostication, and future genetic counselling and also for medicolegal purposes questioning the adequacy of perinatal management. It also emphasises the value of post-mortem in such cases to clinch the diagnosis.
Background The differentiation of transient tachypnea of the newborn from bacterial pneumonia presents an important diagnostic dilemma in Neonatal Intensive Care Unit. Aim To evaluate the predictive ...value of procalcitonin for transient tachypnea of the newborn. Methods Total 122 babies were included to study. All babies were term. Babies were categorized into three groups: If the baby has prominent grunting after 2. hours of age (Group 1, n=38), if grunting subsided at 2. hours of age and baby has only tachypnea at 24 hours of age (Group 2, n=41), if respiratory distress signs minimal or absent at 24 hours of age (Group 3, n=43). In all groups, procalcitonin levels were determined at birth and 24 hours of age. Results Procalcitonin levels at birth were significantly higher in Group 1 than other groups, but there was no difference between Groups 2 and 3. Procalcitonin levels at 24 hours of age were significantly higher in Group 1 and 2 than Group 3. No difference was found between Group 1 and Group 2 at 24 hours of age. All procalcitonin values in Group 3 were significantly lower than other groups. PCT tresholds for the diagnosis of transient tachypnea of the newborn were 0.49 ng/ml at birth (sensitivity 59%, specificity 51%); and 5.88ng/ml at 24h of life (sensitivity 80.2%, specificity 90.7%). Conclusions Serial procalcitonin measurement at birth and 24 hours of age may be helpful in differentiating between pneumonia and transient tachypnea of the newborn. Larger studies are needed to confirm our preliminary results.
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