http://hdl.handle.net/10366/154144 Tue, 21 Apr 2026 12:53:31 GMT 2026-04-21T12:53:31Z http://hdl.handle.net/10366/155312 [EN]Cerebral preconditioning (PC) confers endogenous brain protection after stroke. Ischemic stroke patients with a prior transient ischemic attack (TIA) may potentially be in a preconditioned state. Although PC has been associated with the activation of pro-survival signals, the mechanism by which preconditioning confers neuroprotection is not yet fully clarified. Recently, we have described that PC-mediated neuroprotection against ischemic insult is promoted by p53 destabilization, which is mediated by its main regulator MDM2. Moreover, we have previously described that the human Tp53 Arg72Pro single nucleotide polymorphism (SNP) controls susceptibility to ischemia-induced neuronal apoptosis and governs the functional outcome of patients after stroke. Here, we studied the contribution of the human Tp53 Arg72Pro SNP on PC-induced neuroprotection after ischemia. Our results showed that cortical neurons expressing the Pro72-p53 variant exhibited higher PC-mediated neuroprotection as compared with Arg72-p53 neurons. PC prevented ischemia-induced nuclear and cytosolic p53 stabilization in Pro72-p53 neurons. However, PC failed to prevent mitochondrial p53 stabilization, which occurs in Arg72-p53 neurons after ischemia. Furthermore, PC promoted neuroprotection against ischemia by controlling the p53/active caspase-3 pathway in Pro72-p53, but not in Arg72-p53 neurons. Finally, we found that good prognosis associated to TIA within 1 month prior to ischemic stroke was restricted to patients harboring the Pro72 allele. Our findings demonstrate that the Tp53 Arg72Pro SNP controls PC-promoted neuroprotection against a subsequent ischemic insult by modulating mitochondrial p53 stabilization and then modulates TIA-induced ischemic tolerance. Mon, 01 Apr 2019 00:00:00 GMT http://hdl.handle.net/10366/155312 2019-04-01T00:00:00Z http://hdl.handle.net/10366/155018 [EN] The aim of this study was to translate and adapt the physical activity and leisure motivation scale (PALMS) into Spanish, and to analyse its validity and reliability. The sample comprised 867 adolescents, with a mean age of 14.04 ± 1.19 years, 53.9% of whom were male. During the translation process, some of the items in the instrument were modified slightly, improving its comprehensibility. On the other hand, the exploratory factor analysis did not present an adequate factor structure, so a more in-depth analysis was carried out, using item response theory and confirmatory factor analysis; the conclusion was that it would be appropriate to eliminate several items from the scale. From this, a final shortened version, consisting of 25 items, was produced, with adequate fit indices—CFI = 0.933, TLI = 0.918, SRMR = 0.042, RMSEA = 0.052 (90% CI 0.048; 0.056)—and good reliability for each of the dimensions, ranging from 0.625 to 0.835. It can be concluded that the abbreviated version of the PALMS instrument, adapted for Spanish adolescents (PALMS-e), is a valid and reliable instrument for assessing their motives for doing physical activity. Fri, 01 Jan 2021 00:00:00 GMT http://hdl.handle.net/10366/155018 2021-01-01T00:00:00Z http://hdl.handle.net/10366/154999 [EN]Background: One of the most important concepts within Cognitive Social Theory as framed by Bandura is the perceived self-effi cacy; this concept became widespread in 1981 when Mathias Jerusalem and Ralf Schwarzer, using 10 items, established a one-dimensional and universal construct of this scale. The main purpose of this study is to show that the General SelfEffi cacy Scale (GSE) is not a one-dimensional and universal construct, as is currently assumed. Method: The data from 19,719 people from 26 countries were analyzed. In order to identify and understand invariance we applied seven multivariate statistical techniques. Results: The fi ndings suggest the existence of a multidimensional structure and differential item functioning by country. Insofar as there is differential item functioning by country and it is not possible to universalize it, and there are several items on the scale that statistically constitute additional factors. The results confi rm that the self-effi cacy construct is neither universal nor unidimensional. Conclusions: A psychometric instrument must be valued and used with great care; the one in question is being used in a generalized way. Mon, 01 Jan 2018 00:00:00 GMT http://hdl.handle.net/10366/154999 2018-01-01T00:00:00Z http://hdl.handle.net/10366/146420 [EN]This paper presents an ensemble based classification proposal for predicting neurological outcome of severely traumatized patients. The study comprises both the whole group of patients and a subgroup containing those patients suffering traumatic brain injury (TBI). Data was gathered from patients hospitalized in the Intensive Care Unit (ICU) of the University Hospital in Salamanca. Predictive models were induced from both epidemiologic and clinical variables taken at the emergency room and along the stay in the ICU. The large number of variables leads to a low accuracy in the classifiers even when feature selection methods are used. In addition, the presence of a much larger number of instances of one of the classes in the subgroup of TBI patients produces a significantly lesser precision for the minority class. Sun, 01 Jan 2017 00:00:00 GMT http://hdl.handle.net/10366/146420 2017-01-01T00:00:00Z