c-Ski in health and disease

c-Ski is an evolutionary conserved protein that is involved in diverse cellular processes such as proliferation, differentiation, transformation, and tumor progression. A large range of cellular partners of c-Ski, including transcription factors, chromatin-remodeling molecules, tumor suppressors, and nuclear hormone receptors, has been identified. Moreover, numerous mechanisms have been described by which c-Ski regulates essential signaling pathways, e.g., the TGFβ pathway. In this review, we summarize the diverse roles attributed to c-Ski during normal development and in cancer progression and discuss future strategies to unravel further the complex nature of c-Ski actions in a context-dependent manne

Protein 4.1B Contributes to the Organization of Peripheral Myelinated Axons

Neurons are characterized by extremely long axons. This exceptional cell shape is likely to depend on multiple factors including interactions between the cytoskeleton and membrane proteins. In many cell types, members of the protein 4.1 family play an important role in tethering the cortical actin-spectrin cytoskeleton to the plasma membrane. Protein 4.1B is localized in myelinated axons, enriched in paranodal and juxtaparanodal regions, and also all along the internodes, but not at nodes of Ranvier where are localized the voltage-dependent sodium channels responsible for action potential propagation. To shed light on the role of protein 4.1B in the general organization of myelinated peripheral axons, we studied 4.1B knockout mice. These mice displayed a mildly impaired gait and motility. Whereas nodes were unaffected, the distribution of Caspr/paranodin, which anchors 4.1B to the membrane, was disorganized in paranodal regions and its levels were decreased. In juxtaparanodes, the enrichment of Caspr2, which also interacts with 4.1B, and of the associated TAG-1 and Kv1.1, was absent in mutant mice, whereas their levels were unaltered. Ultrastructural abnormalities were observed both at paranodes and juxtaparanodes. Axon calibers were slightly diminished in phrenic nerves and preterminal motor axons were dysmorphic in skeletal muscle. βII spectrin enrichment was decreased along the axolemma. Electrophysiological recordings at 3 post-natal weeks showed the occurrence of spontaneous and evoked repetitive activity indicating neuronal hyperexcitability, without change in conduction velocity. Thus, our results show that in myelinated axons 4.1B contributes to the stabilization of membrane proteins at paranodes, to the clustering of juxtaparanodal proteins, and to the regulation of the internodal axon caliber

c-Ski in health and disease

c-Ski is an evolutionary conserved protein that is involved in diverse cellular processes such as proliferation, differentiation, transformation, and tumor progression. A large range of cellular partners of c-Ski, including transcription factors, chromatin-remodeling molecules, tumor suppressors, and nuclear hormone receptors, has been identified. Moreover, numerous mechanisms have been described by which c-Ski regulates essential signaling pathways, e.g., the TGFβ pathway. In this review, we summarize the diverse roles attributed to c-Ski during normal development and in cancer progression and discuss future strategies to unravel further the complex nature of c-Ski actions in a context-dependent manner

Le risque dans la pratique de l’escalade

Die «risikoreichen verhaltensweisen» der jugendlichen : herausforderung, kurzsichtigkeit oder verweigerung ? Die risikoreichen Verhaltensweisen der Jugendlichen werden generell als Herausforderungen, die Ausdruck eines psychologischen Unbehagens sind, oder als Folge einer Kurzsichtigkeit, einer Unfähigkeit, die Gefahr korrekt einzuschätzen, ausgelegt. Dieser Artikel legt eine kritische Darstellung dieser Kategorie der «risikoreichen Verhaltensweisen der Jugendlichen», die durch die Gesellschaft der Erwachsenen aufgebaut wird, dar, stellt Fragen über den Sinn der Herausforderungsverhalten und ersetzt die vermeintliche Kurzsichtigkeit der Jugendlichen durch eine Auslegung in Form von Risikoverweigerung. Er positioniert diese Analysen im Rahmen der Theorie der Risikogesellschaft von Beck und Giddens.Risk in climbing The aim of this study is to get the meaning of the risk experience for the expert climbers. The experience of strong sensations provoked by the fear of fall or void illustrates the omnipresence of risk in climbing practice. Mainly of symbolic nature which does not threaten physical integrity, risk is perceived and assessed in a differentiated way according to the climbers, the spatiotemporal and social context. The engagement of the climber who accepts the perspective of fall, is justified by several factors.L’objectif de cette étude est d’envisager le sens de l’expérience du risque chez les grimpeurs experts. Vécu sous une forme majoritairement symbolique qui ne menace pas l’intégrité physique des pratiquants, le risque est apprécié de façon différenciée selon les personnes et le contexte spatio-temporel et social.El riesgo en la práctica de la escalada El propósito de este estudio es acceder al significado de la experiencia del riesgo para los escaladores experimentados. La experiencia de sensaciones fuertes, provocadas por el miedo a la caída o al vacío, ilustra la omnipresencia del riesgo en la práctica de la escalada. De naturaleza mayormente simbólica, que no amenaza a la integridad física, el riesgo se percibe y aprecia de manera diferenciada según los practicantes y el contexto espacio-temporal y social. El compromiso del escalador que asume la perspectiva de la caída está motivado por varios factores.Martha Cécile, Bonnon Michel, Griffet Jean. Le risque dans la pratique de l’escalade. In: Agora débats/jeunesses, 27, 2002. Les jeunes et le risque. pp. 74-85

Fixação com pino intramedular em fratura do fêmur em Tamanduá Bandeira, Myrmecophaga Tridactyla1- Linnaeus, 1758. Relato de caso

An ant eater male 30 kg was found on a highway at Ilha Solteira- SP, and were taken to Wild Conservation Center (WCC), where he was diagnosed with a simple oblique fracture in the diaphisi’s femur, and a fracture in radio-ulna, both on the right side. The animal was subjected to surgical procedures for fixation of the femur. After the first fixation, the fracture was reduced with good alignment of the bone and rotation movements were completely absent. Two days after surgery was done X-rays, that showed that the intramedullary pin was moved, causing an unacceptable alignment of the bone. Were done a second surger to remov the pin and put other. Seven days after the second surgery, the wound showed signs of infection and the animal was anesthetized for further evaluation, and the intramedullary pin was found to have doubled again. Considering these signs, progressive weight loss of the animal and the aggressive nature, made the intensive care impossible without daily sedation, and from that, the option to euthanize the animal was the best choice. The post mortem evaluation confirmed the surgical site infection, although local and systemic antibiotic therapyUm tamanduá bandeira macho de 30 kg foi levado para o Centro de Conservação da Fauna Silvestre (CCFS), onde foi diagnosticado com uma fratura simples oblíqua na diáfise do fêmur, e uma fratura de rádio e ulna, ambos no lado direito. O animal foi submetido a 2 procedimentos cirúrgicos para fixação do fêmur. Após primeira fixação, a fratura foi reduzida com um bom alinhamento do osso e movimentos de rotação eram completamente ausentes, porém dois dias após a cirurgia foi feito um raio-X, o qual revelou que o pino intramedular tinha dobrado, causando um alinhamento inaceitável do osso. Realizou-se uma segunda cirurgia, na qual foi retirado o pino dobrado e colocou-se outro, mas sete dias após, a ferida apresentou sinais de infecção e para facilitar a inspeção, o animal foi anestesiado e o pino intramedular revelou ter dobrado novamente. Considerando esses sinais, a perda de peso progressiva do animal e a seu comportamento agressivo que tornava o tratamento intensivo impossível sem sedação diária, e a partir disso, a opção de eutanasiar o animal foi a melhor escolha, para evitar mais sofrimento. A avaliação pós mortem confirmou a infecção de sítio cirúrgico, apesar de antibioticoterapia local e sistêmica