Programming Hippocampal Neural Stem/Progenitor Cells into Oligodendrocytes Enhances Remyelination in the Adult Brain after Injury.

Demyelinating diseases are characterized by a loss of oligodendrocytes leading to axonal degeneration and impaired brain function. Current strategies used for the treatment of demyelinating disease such as multiple sclerosis largely rely on modulation of the immune system. Only limited treatment options are available for treating the later stages of the disease, and these treatments require regenerative therapies to ameliorate the consequences of oligodendrocyte loss and axonal impairment. Directed differentiation of adult hippocampal neural stem/progenitor cells (NSPCs) into oligodendrocytes may represent an endogenous source of glial cells for cell-replacement strategies aiming to treat demyelinating disease. Here, we show that Ascl1-mediated conversion of hippocampal NSPCs into mature oligodendrocytes enhances remyelination in a diphtheria-toxin (DT)-inducible, genetic model for demyelination. These findings highlight the potential of targeting hippocampal NSPCs for the treatment of demyelinated lesions in the adult brain.

Development process and initial validation of the ethical conflict in nursing questionnaire-critical care version

Background: Ethical conflicts are arising as a result of the growing complexity of clinical care, coupled with technological advances. Most studies that have developed instruments for measuring ethical conflict base their measures on the variables"frequency" and"degree of conflict". In our view, however, these variables are insufficient for explaining the root of ethical conflicts. Consequently, the present study formulates a conceptual model that also includes the variable"exposure to conflict", as well as considering six"types of ethical conflict". An instrument was then designed to measure the ethical conflicts experienced by nurses who work with critical care patients. The paper describes the development process and validation of this instrument, the Ethical Conflict in Nursing Questionnaire Critical Care Version (ECNQ-CCV). Methods: The sample comprised 205 nursing professionals from the critical care units of two hospitals in Barcelona (Spain). The ECNQ-CCV presents 19 nursing scenarios with the potential to produce ethical conflict in the critical care setting. Exposure to ethical conflict was assessed by means of the Index of Exposure to Ethical Conflict (IEEC), a specific index developed to provide a reference value for each respondent by combining the intensity and frequency of occurrence of each scenario featured in the ECNQ-CCV. Following content validity, construct validity was assessed by means of Exploratory Factor Analysis (EFA), while Cronbach"s alpha was used to evaluate the instrument"s reliability. All analyses were performed using the statistical software PASW v19. Results: Cronbach"s alpha for the ECNQ-CCV as a whole was 0.882, which is higher than the values reported for certain other related instruments. The EFA suggested a unidimensional structure, with one component accounting for 33.41% of the explained variance. Conclusions: The ECNQ-CCV is shown to a valid and reliable instrument for use in critical care units. Its structure is such that the four variables on which our model of ethical conflict is based may be studied separately or in combination. The critical care nurses in this sample present moderate levels of exposure to ethical conflict. This study represents the first evaluation of the ECNQ-CCV.

Commotion cérébrale chez l'enfant et l'adolescent sportif [Concussion in children and adolescents during sports].

Concussion, a frequent injury in sports, is rarely evoked and often trivialized in children and teenagers. Knowledge of the diverse symptoms and signs to seek for is essential to an appropriate and secure management. The initial treatment relies on cognitive and physical rest followed by a progressive return to school and subsequently sport activities. The aim of this article is to review an injury whose prognosis is generally favourable, but whose rare complications can prove dramatic.

Development process and initial validation of the ethical conflict in nursing questionnaire-critical care version

Background: Ethical conflicts are arising as a result of the growing complexity of clinical care, coupled with technological advances. Most studies that have developed instruments for measuring ethical conflict base their measures on the variables"frequency" and"degree of conflict". In our view, however, these variables are insufficient for explaining the root of ethical conflicts. Consequently, the present study formulates a conceptual model that also includes the variable"exposure to conflict", as well as considering six"types of ethical conflict". An instrument was then designed to measure the ethical conflicts experienced by nurses who work with critical care patients. The paper describes the development process and validation of this instrument, the Ethical Conflict in Nursing Questionnaire Critical Care Version (ECNQ-CCV). Methods: The sample comprised 205 nursing professionals from the critical care units of two hospitals in Barcelona (Spain). The ECNQ-CCV presents 19 nursing scenarios with the potential to produce ethical conflict in the critical care setting. Exposure to ethical conflict was assessed by means of the Index of Exposure to Ethical Conflict (IEEC), a specific index developed to provide a reference value for each respondent by combining the intensity and frequency of occurrence of each scenario featured in the ECNQ-CCV. Following content validity, construct validity was assessed by means of Exploratory Factor Analysis (EFA), while Cronbach"s alpha was used to evaluate the instrument"s reliability. All analyses were performed using the statistical software PASW v19. Results: Cronbach"s alpha for the ECNQ-CCV as a whole was 0.882, which is higher than the values reported for certain other related instruments. The EFA suggested a unidimensional structure, with one component accounting for 33.41% of the explained variance. Conclusions: The ECNQ-CCV is shown to a valid and reliable instrument for use in critical care units. Its structure is such that the four variables on which our model of ethical conflict is based may be studied separately or in combination. The critical care nurses in this sample present moderate levels of exposure to ethical conflict. This study represents the first evaluation of the ECNQ-CCV.

Neuroenergetic Response to Prolonged Cerebral Glucose Depletion after Severe Brain Injury and the Role of Lactate.

Lactate may represent a supplemental fuel for the brain. We examined cerebral lactate metabolism during prolonged brain glucose depletion (GD) in acute brain injury (ABI) patients monitored with cerebral microdialysis (CMD). Sixty episodes of GD (defined as spontaneous decreases of CMD glucose from normal to low [<1.0 mmol/L] for at least 2 h) were identified among 26 patients. During GD, we found a significant increase of CMD lactate (from 4±2.3 to 5.4±2.9 mmol/L), pyruvate (126.9±65.1 to 172.3±74.1 μmol/L), and lactate/pyruvate ratio (LPR; 27±6 to 35±9; all, p<0.005), while brain oxygen and blood lactate remained normal. Dynamics of lactate and glucose supply during GD were further studied by analyzing the relationships between blood and CMD samples. There was a strong correlation between blood and brain lactate when LPR was normal (r=0.56; p<0.0001), while an inverse correlation (r=-0.11; p=0.04) was observed at elevated LPR >25. The correlation between blood and brain glucose also decreased from r=0.62 to r=0.45. These findings in ABI patients suggest increased cerebral lactate delivery in the absence of brain hypoxia when glucose availability is limited and support the concept that lactate acts as alternative fuel.

The initial oxidation of transition metal surfaces

Due to their numerous novel technological applications ranging from the example of exhaust catalysts in the automotive industry to the catalytic production of hydro- gen, surface reactions on transition metal substrates have become to be one of the most essential subjects within the surface science community. Although numerous applications exist, there are many details in the different processes that, after many decades of research, remain unknown. There are perhaps as many applications for the corrosion resistant materials such as stainless steels. A thorough knowledge of the details of the simplest reactions occuring on the surfaces, such as oxidation, play a key role in the design of better catalysts, or corrosion resistant materials in the future. This thesis examines the oxidation of metal surfaces from a computational point of view mostly concentrating on copper as a model material. Oxidation is studied from the initial oxidation to the oxygen precovered surface. Important parameters for the initial sticking and dissociation are obtained. The saturation layer is thoroughly studied and the calculated results arecompared with available experimental results. On the saturated surface, some open questions still remain. The present calculations demonstrate, that the saturated part of the surface is excluded from being chemically reactive towards the oxygen molecules. The results suggest, that the reason for the chemical activity of the saturated surface is due to a strain effect occuring between the saturated areas of the surface.

Erratum of initial paper: Postmortem computed tomography angiography vs. conventional autopsy: advantages and inconveniences of each method.

PURPOSE: Postmortem computed tomography angiography (PMCTA) was introduced into forensic investigations a few years ago. It provides reliable images that can be consulted at any time. Conventional autopsy remains the reference standard for defining the cause of death, but provides only limited possibility of a second examination. This study compares these two procedures and discusses findings that can be detected exclusively using each method. MATERIALS AND METHODS: This retrospective study compared radiological reports from PMCTA to reports from conventional autopsy for 50 forensic autopsy cases. Reported findings from autopsy and PMCTA were extracted and compared to each other. PMCTA was performed using a modified heart-lung machine and the oily contrast agent Angiofil® (Fumedica AG, Muri, Switzerland). RESULTS: PMCTA and conventional autopsy would have drawn similar conclusions regarding causes of death. Nearly 60 % of all findings were visualized with both techniques. PMCTA demonstrates a higher sensitivity for identifying skeletal and vascular lesions. However, vascular occlusions due to postmortem blood clots could be falsely assumed to be vascular lesions. In contrast, conventional autopsy does not detect all bone fractures or the exact source of bleeding. Conventional autopsy provides important information about organ morphology and remains the only way to diagnose a vital vascular occlusion with certitude. CONCLUSION: Overall, PMCTA and conventional autopsy provide comparable findings. However, each technique presents advantages and disadvantages for detecting specific findings. To correctly interpret findings and clearly define the indications for PMCTA, these differences must be understood.

Forest Transition in Madagascar's Highlands: Initial Evidence and Implications

Madagascar is renowned for the loss of the forested habitat of lemurs and other species endemic to the island. Less well known is that in the highlands, a region often described as an environmental "basket-case" of fire-degraded, eroded grasslands, woody cover has been increasing for decades. Using information derived from publically available high- and medium-resolution satellites, this study characterizes tree cover dynamics in the highlands of Madagascar over the past two decades. Our results reveal heterogeneous patterns of increased tree cover on smallholder farms and village lands, spurred by a mix of endogenous and exogenous forces. The new trees play important roles in rural livelihoods, providing renewable supplies of firewood, charcoal, timber and other products and services, as well as defensible claims to land tenure in the context of a decline in the use of hillside commons for grazing. This study documents this nascent forest transition through Land Change Science techniques, and provides a prologue to political ecological analysis by setting these changes in their social and environmental context and interrogating the costs and benefits of the shift in rural livelihood strategies.

Premières évidences de la validité de l'échelle de désengagement moral pour des actes discriminatoires (Initial evidence of the validity of a scale on moral disengagement in discriminatory behavior)

De nombreuses études ont mis en évidence le fait que les individus étaient prêts à commettre des actes discriminatoires pour autant qu'ils puissent les justifier (Crandall & Eshleman, 2003). Nous proposons de contribuer à la compréhension de ce phénomène grâce au concept de désengagement moral pour des actes discriminatoires (DMD). Nous définissons le désengagement moral comme le fait de justifier ses propres actes immoraux de manière à les rendre acceptable. Ce concept trouve ses origines dans les travaux de Bandura et al. (1996) portant sur les comportements agressifs chez des enfants. Il se compose de huit mécanismes (p.ex. le déplacement de responsabilité). Notre recherche dépasse le cadre théorique développé par Bandura et al. pour inscrire le désengagement moral dans le champ de la discrimination intergroupe. De plus, en conceptualisant le désengagement moral comme une différence individuelle, nous proposons également de présenter les premières étapes du développement d'une échelle permettant de mesurer le DMD. L'échelle de DMD a été développée en trois étapes en suivant la procédure proposée par Hinkin (1998). Tout d'abord, une liste de 72 items a été générée suivant une méthode déductive. Puis, suite à une étude (n = 13) portant sur la cohérence des items vis-à-vis du concept et de ses mécanismes, cette liste a été réduite à 40 items (5 par mécanisme). Enfin, 118 étudiants universitaires ont participé à une étude dans le but de mener des analyses factorielles (exploratoire et confirmatoire), ainsi que de tester les validités convergente, divergente et prédictive de l'échelle. La première partie de cette étude se composait de différentes échelles (p.ex. mesure de personnalité, préjugés anti-immigrés, etc.). La seconde partie de l'étude était une expérience portant sur l'évaluation d'idées de méthodes de sélection (discriminatoire versus méritocratique) des étudiants suisses et étrangers à l'université, ayant pour but de réduire la surpopulation dans les salles de cours. Les résultats obtenus sont prometteurs pour le développement de l'échelle, autant du point de vue de sa structure (p.ex. α = .82) que de sa validité. Par exemple, plus le niveau de DMD des participants était élevé, plus ils étaient favorables à une méthode de sélection discriminatoire des étudiants à l'université. L'ensemble des résultats sera présenté durant la conférence. Nous discuterons également des potentielles contributions de cette échelle pour de futurs projets de recherche. Référence : Bandura, A., Barbaranelli, C., Caprara, G. V., & Pastorelli, C. (1996). Mechanisms of moral disengagement of the exercise of moral agency. Journal of Personality and Social Psychology, 71 (2), 364-374. Crandall, C. S., & Eshleman, A. (2003). The Justification-suppression model of the expression and experience of prejudice. Psychological Bulletin, 129 (3), 414-446. Hinkin, T. R. (1998). A brief tutorial on the development of measures for use un survey questionnaires. Organizational Research Methods, 1 (1), 104.121.

Estimations of topographically correct regeneration to nerve branches and skin after peripheral nerve injury and repair.

Peripheral nerve injury is typically associated with long-term disturbances in sensory localization, despite nerve repair and regeneration. Here, we investigate the extent of correct reinnervation by back-labeling neuronal soma with fluorescent tracers applied in the target area before and after sciatic nerve injury and repair in the rat. The subpopulations of sensory or motor neurons that had regenerated their axons to either the tibial branch or the skin of the third hindlimb digit were calculated from the number of cell bodies labeled by the first and/or second tracer. Compared to the normal control side, 81% of the sensory and 66% of the motor tibial nerve cells regenerated their axons back to this nerve, while 22% of the afferent cells from the third digit reinnervated this digit. Corresponding percentages based on quantification of the surviving population on the experimental side showed 91%, 87%, and 56%, respectively. The results show that nerve injury followed by nerve repair by epineurial suture results in a high but variable amount of topographically correct regeneration, and that proportionally more neurons regenerate into the correct proximal nerve branch than into the correct innervation territory in the skin

Epidemiology and injury patterns of patients consulting following assault by nightclub security agents in a university hospital emergency service and an associated specialised forensic consultation

Introduction: The Violence Medical Unit (VMU), a specialised forensic medical consultation, was created at the Lausanne university Hospital in 2006. All patients consulting at the ED for interpersonal violencerelated injury are referred to the VMU, which provides forensic documentation of the injury and referral to the relevant community based victim-support organisations within 48 hours of the ED visit. This frees the ED medical staff from forensic injury documentation and legal/social referral, tasks for which they lack both time and training. Among community violence, assaults by nightclub security agents against patrons have increased from 6% to 10% between 2007 and 2009. We set out to characterise the demographics, assault mechanisms, subsequent injuries, prior alcohol intake and ED & VMU costs incurred by this group of patients. Methods: We retrospectively included all patients consulting at the VMU due to assault by nightclub security agents from January 2007 to December 2009. Data was obtained from ED & VMU medical, nursing and administrative records. Results: Our sample included 70 patients, of which 64 were referred by the CHUV ED. The victims were typically young (median age 29) males (93%). 77% of assaults occurred on the weekend between 12 PM and 4 AM, and 73% of the victims were under the influence of alcohol. 83% of the patients were punched, kicked and/or head-butted; 9% had been struck with a blunt instrument. 80% of the injuries were in the head and neck area and 19% of the victims sustained fractures. 21% of the victims were prescribed medical leave. Total ED & VMU costs averaged 1048 SFr. Conclusion: Medical staff treating this population of assault victims must be aware of the assault mechanisms and injury patterns, in particular the high probability of fractures, in order to provide adequate diagnosis and care. Associated inebriation mandates liberal use of radiology, as delayed or missed diagnosis may have medical, medicolegal and legal implications. Emergency medical services play an important role in detecting and reporting of such incidents. Centralised management of the forensic documentation facilitates referral to victim support organisations and epidemiological data collection. Magnitudes and trends of the different types of violence can be determined, and this information can be then impact public safety management policies.

Le stress chez l'aidant naturel dont le proche est en traitement initial d'un cancer du poumon

Le cancer du poumon fait partie des cancers les plus fréquents. Diagnostiqué à un stade souvent tardif, il se caractérise par un mauvais pronostic et de lourdes répercussions sur la santé du patient. La phase de traitement initial représente un moment critique où les proches du patient deviennent aidants naturels du patient et endossent de nouvelles responsabilités. Cette situation génère des conséquences en termes de stress chez l'aidant naturel. Le but de cette étude était de décrire l'importance du stress chez l'aidant naturel du patient en traitement initial pour un cancer du poumon. L'approche méthodologique utilisée est de type descriptif transversal. L'échantillon de convenance était composé de 28 aidants naturels et 26 patients en traitement initial pour un cancer du poumon suivis dans un centre d'oncologie ambulatoire universitaire en Suisse. L'importance du stress des aidants naturels a été évaluée à partir de l'instrument Caregiver Reaction Assessment (CRA) de Given et al. (1992) complété d'une question mesurant la perception du manque d'information. Le CRA mesure le ressenti de l'aidant naturel face aux dimensions négatives et positive du stress sur une échelle de type Likert à cinq points. Le modèle des systèmes de Neuman (2002) a servi de cadre théorique à l'étude. Les aidants naturels ont accordé une importance plus élevée (score moyen 4,15) à l'Estime de soi, dimension positive du stress qu'aux dimensions négatives. Parmi celles-ci, la Perturbation des activités représente la dimension qui affecte le plus le quotidien des aidants (score moyen 2,96). Les caractéristiques sociodémographiques de l'aidant et les données médicales du patient, semblent avoir une influence sur l'importance du stress perçu, mais d'autres marqueurs objectifs doivent être identifiés pour affiner l'interprétation de ces relations. Une grande majorité (78%) des aidants ont indiqué qu'ils disposaient d'assez d'information pour soigner, indiquant que l'information est un sujet important dans leur vécu et mérite une évaluation plus poussée en tant que dimension du stress associé au rôle d'aidant naturel. L'infirmière doit viser par ses actions à préserver l'intégrité et la stabilité de la santé de l'aidant naturel comme elle le fait pour les patients. L'investigation systématique du stress représente une intervention prioritaire chez les aidants naturels dans le contexte oncologique. Des interventions personnalisées pourront être ainsi développées, afin de soutenir l'aidant naturel dans ses activités d'aide auprès de son proche tout en préservant sa propre santé.

Spinal cord injury affects the interplay between visual and sensorimotor representations of the body.

The brain integrates multiple sensory inputs, including somatosensory and visual inputs, to produce a representation of the body. Spinal cord injury (SCI) interrupts the communication between brain and body and the effects of this deafferentation on body representation are poorly understood. We investigated whether the relative weight of somatosensory and visual frames of reference for body representation is altered in individuals with incomplete or complete SCI (affecting lower limbs' somatosensation), with respect to controls. To study the influence of afferent somatosensory information on body representation, participants verbally judged the laterality of rotated images of feet, hands, and whole-bodies (mental rotation task) in two different postures (participants' body parts were hidden from view). We found that (i) complete SCI disrupts the influence of postural changes on the representation of the deafferented body parts (feet, but not hands) and (ii) regardless of posture, whole-body representation progressively deteriorates proportionally to SCI completeness. These results demonstrate that the cortical representation of the body is dynamic, responsive, and adaptable to contingent conditions, in that the role of somatosensation is altered and partially compensated with a change in the relative weight of somatosensory versus visual bodily representations.

Fondaparinux in the initial and long-term treatment of venous thromboembolism.

BACKGROUND: Even in the absence of evidence on its long-term efficacy and safety, a number of patients with venous thromboembolism (VTE) receive long-term therapy with fondaparinux alone in everyday practice. METHODS: We used the Registro Informatizado de Enfermedad Tromboembólica (RIETE) registry to compare the rate of VTE recurrences and major bleeding at 10 and 90 days in patients with and without cancer. For long-term therapy, fondaparinux was compared with vitamin K antagonists (VKA) in patients without cancer and with low-molecular-weight heparin (LMWH) in those with cancer. RESULTS: Of 47,378 patients recruited, 46,513 were initially treated with heparin, 865 with fondaparinux. Then, 263 patients (78 with cancer) were treated for at least 3 months with fondaparinux. After propensity-score matching, there were no differences between patients receiving initial therapy with heparin or fondaparinux. Among patients with cancer, there were no differences between fondaparinux and LMWH. Among patients without cancer, the long-term use of fondaparinux was associated with an increased risk of major bleeding (3.24 % vs. 0.95 %, p<0.05). CONCLUSIONS: An unexpected high rate of major bleeding was observed in non-cancer patients treated with long-term fondaparinux. Our small sample does not allow to derive relevant conclusions on the use of fondaparinux in cancer patients.