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111.
Canavan disease: a white matter disorder   总被引:1,自引:0,他引:1  
Breakdown of oligodendrocyte-neuron interactions in white matter (WM), such as the loss of myelin, results in axonal dysfunction and hence a disruption of information processing between brain regions. The major feature of leukodystrophies is the lack of proper myelin formation during early development or the onset of myelin loss late in life. These early childhood WM diseases are described as hypomyelination or dysmyelination arising from a primary block in normal myelin synthesis because of a genetic mutation expressed in oligodendrocytes, or failure in myelination secondary to neuronal or astroglial dysfunctions (van der Knaap 2001 Dev. Med. Child Neurol. 43:705-712). Here, we describe the pathophysiological parameters of Canavan disease (CD), caused by genetic mutations of the aspartoacylase (ASPA) gene, a metabolic enzyme restricted in the central nervous system (CNS) to oligodendrocytes. CD presents pathophysiological dysfunctions similar to diseases caused by myelin gene mutations, such as Pelizaeus-Merzbacher disease (PMD) and several animal models, such as myelin deficient rat (md), jimpy (jp), shiverer (sh), and quaking (qk viable) mutant mice. These single gene mutations have pleiotropic effects, whereby the alteration of one myelin gene expression disrupts functional expression of other oligodendrocyte genes with an outcome of hypomyelination/dysmyelination. Among all of the known leukodystrophies, CD is the first disorder, which was approved and tested for the adeno-associated virus vector (AAV)-ASPA gene therapy (Leone et al. 2000 Ann. Neurol. 48:27-38; Janson et al. 2001 Trends Neurosci. 24:706-712) without much success following the first two attempts. ASPA gene delivery attempts in animal models have shown a lowering of N-acetyl L-aspartate and a change in motor functions, while sponginess of the WM, a characteristic of CD remained unchanged (Matalon et al. 2003 Mol. Ther. 7 (5, Part 1):580-587; McPhee et al. 2005 Brain Res. Mol. Brain Res. 135:112-121) even with better viral serotype and delivery of the gene during early phase of development (Klugmann et al. 2005 Mol. Ther. 11:745-753). While different approaches are being sought for the success of gene therapy, there are pivotal developmental questions to address regarding the specific regions of the CNS and cell lineages that become the target for the onset and progression of CD symptoms from early to late stages of development.  相似文献   
112.
The authors investigated whether visual fixations during a continuous graphical task were related to arm endpoint kinematics, joint motions, or joint control. The pattern of visual fixations across various shapes and the relationship between temporal and spatial events of the moving limb and visual fixations were assessed. Participants (N=16) performed movements of varying shapes by rotating the shoulder and elbow joints in the transverse plane at a comfortable pace. Across shapes, eye movements consisted of a series of fixations, with the eyes leading the hand. Fixations were spatially related to modulation of joint motion and were temporally related to the portions of the movement where curvature was the highest. Gathering of information related to modulation of interactive torques arising from passive forces from movement of a linked system occurred when the velocity of the movement (a) was the lowest and (b) was ahead of the moving limb, suggesting that that information is used in a feedforward manner.  相似文献   
113.
International comparisons of previous convictions (PC) and crime scene behaviours (CSB) of stranger sexual offences can inform offender profiling strategies; especially the degree to which pragmatic models cross validate across countries. The present study compared PC and CSB of 474 UK and 418 Spanish cases. CSB and PC were analysed using Chi-square. UK stranger sexual offenders displayed a higher proportion of all CSB analysed. UK offenders also had a significantly higher proportion of PC with the exception of violence offences. There were no significant differences in sexual pre-convictions. In both the UK and Spain the CSB ‘reference to the police’ was significantly association with the PC ‘Criminal damage’ no other similar significant associations were found. Explanations for these findings include differences between the countries in regards to: legislation, crime recording processes, data coding processes, with additional consideration of any cultural, environmental and contextual factors.  相似文献   
114.
Creativity is a fundamental human accomplishment from scientific advances to composing music. The left dorsolateral prefrontal cortex (DLPFC) and inferior frontal gyrus (IFG) are important metacontrol hubs in flexibility and persistence brain states, respectively. Those hubs are related to divergent thinking, insight problem-solving, and convergent thinking. In this double-blind, between-subjects study, 81 healthy participants were randomly assigned to one of three groups (n = 27) that received a combined transcranial direct current stimulation–transcranial random noise stimulation (tDCS-tRNS) protocol with the anode over the left DLPFC and cathode over the left IFG (+DLPFC−IFG), the opposite montage (−DLPFC+IFG), and a sham group (+DLPFC−IFG). Both active tDCS-tRNS groups received 20 min of 1 mA tDCS with 1 mA (100–500 Hz) tRNS. Creativity was assessed before (baseline) and during stimulation with the Unusual Uses, Picture Completion (PC), Remote Association test (RAT), Matchstick Arithmetic (MA), and Nine-dot (ND) problems. Only the +DLPFC−IFG group had significantly higher scores compared with sham in the RAT (p = .009), PC fluency (p = .018), PC originality (p = .007), ND (p = .007), and MA (p = .032). Overall, −DLPFC+IFG had greater scores in all creativity tests compared with sham. Implications from the metacontrol theory are discussed.  相似文献   
115.
The present study explored prospective links between trait mindfulness and compassion on subsequent coping and compliance with Centers for Disease Control (CDC) guidelines and indirect effects via well-being and internalized distress during the COVID-19 pandemic. The study included N = 736 US college students who participated in a three-wave longitudinal study across a single academic year. The first two assessment waves took place in 2018 and 2019, respectively, while the third wave took place in May 2020 during the COVID-19 pandemic. Participants completed self-report measures of trait mindfulness, compassion, well-being, internalized distress, coping, and compliance with CDC health guidelines. Results of a series of autoregressive, cross-lagged panel models revealed that trait mindfulness was associated with better coping via indirect effects of greater well-being and lower internalized distress. Greater compassion was linked with greater adherence to CDC guidelines. Findings suggest that trait mindfulness and compassion may play a role in college students' coping and compliance during the pandemic.  相似文献   
116.
The article presents results of an ongoing study of centers of intellectual innovations in post-Soviet Russia. Using the European University at St. Petersburg as the main object of their analysis, the authors demonstrate how new models of academic careers, which became available in the 1980s and 1990s, were eventually institutionalized as new models of knowledge production and educational practices. Supported by American foundations, this private university had to invent a new institutional structure and to position itself within the field of higher education, still mostly dominated by the state.  相似文献   
117.
More than twenty five years after the beginning of research on spontaneous trait inferences (Winter & Uleman, 1984) an intriguing paradox in the impression formation literature remains: if traits are spontaneously inferred, why aren't they used to organize behavioral information and thereby facilitate recall under memory instructions (Hamilton, Katz, & Leirer, 1980)? We hypothesized that organization by traits is more evident under impression formation goals because only in that case then are inferences sufficiently monitored to permit their use in organizing impressions. As a consequence, such monitored traits can then be used strategically as retrieval cues. Merging the main features of the Winter and Uleman and the Hamilton et al. experimental paradigms, Experiment 1 simultaneously replicated the main results of both studies. Using a new recognition paradigm, Experiments 2 and 3 further tested this inference monitoring hypothesis by showing that monitoring of trait inferences only occurs under particular processing goals, and is dependent on the availability of cognitive resources.  相似文献   
118.
119.
Refining the theory of basic individual values   总被引:2,自引:0,他引:2  
We propose a refined theory of basic individual values intended to provide greater heuristic and explanatory power than the original theory of 10 values (Schwartz, 1992). The refined theory more accurately expresses the central assumption of the original theory that research has largely ignored: Values form a circular motivational continuum. The theory defines and orders 19 values on the continuum based on their compatible and conflicting motivations, expression of self-protection versus growth, and personal versus social focus. We assess the theory with a new instrument in 15 samples from 10 countries (N = 6,059). Confirmatory factor and multidimensional scaling analyses support discrimination of the 19 values, confirming the refined theory. Multidimensional scaling analyses largely support the predicted motivational order of the values. Analyses of predictive validity demonstrate that the refined values theory provides greater and more precise insight into the value underpinnings of beliefs. Each value correlates uniquely with external variables.  相似文献   
120.
Previous research using the Deese–Roediger–McDermott (DRM) paradigm has shown that lists of associates in which the critical words were easily identified as the themes of the lists produce lower levels of false memories in adults. In an attempt to analyze whether this effect is due to the application of a specific memory-editing process (the identify-to-reject strategy), two experiments manipulated variables that are likely to disrupt this strategy either at encoding or at retrieval. In Experiment 1, lists were presented at a very fast presentation rate to reduce the possibility of identifying the missing critical word as the theme of the list, and in Experiment 2, participants were pressed to give yes/no recognition answers within a very short time. The results showed that both of these manipulations disrupted the identifiability effect, indicating that the identify-to-reject strategy and theme identifiability play a major role in the rejection of false memories in the DRM paradigm.  相似文献   
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