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41.
Seizures in newborns do not always show a clear electro-clinical correlation. The real epileptic nature of some stereotyped rhythmic movements, included in the ‘subtle seizures’ and considered as brainstem release phenomena, is still debated. We report a brain injured newborn, who displayed several episodes of repetitive limb movements. The ictal EEG discharge, during one of these episodes, was associated with a motor pattern modification, which was endowed with quadrupedal locomotion kinematic features. This might represent an indirect evidence of cervical and lumbar Central Pattern Generators interconnection with in-phase coordination between diagonal limbs since the first hours of life in humans.  相似文献   
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Vision and motor skills are intimately linked, both in their own development and functionally. The solicitation of one can therefore promote the development of the other. The various professionals of motor skills (physiotherapist, psychomotor therapists, occupational therapists) and the orthoptists are called upon to integrate these aspects in the follow-up of the patients, as well in the guides as in the installations.  相似文献   
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BackgroundMultiple sclerosis (MS) is a demyelinating disorder of the central nervous system with heterogeneous symptoms. Persons with MS (PwMS) show reduced walking capacity with changes in their gait pattern. It is unknown to which extent coordination deficits are present in PwMS, which can be measured by seated lower leg interlimb coordination tasks, and to which extent they are related to motor and cognitive function.Research questionHow is the control of interlimb coordination of the lower limbs characterized in PwMS compared to healthy controls (HC) during a seated rhythmical coordination task and what is the relationship between interlimb coordination, motor or cognitive function?MethodsRhythmical interlimb coordination was assessed during a single session in 38 PwMS and 13 HC, using a seated rhythmical coordination task, comprising of antiphase flexion-extension of the lower limbs, to metronomes at 0.75 Hz, 1.00 Hz, 1.50 Hz. Outcomes were phase coordination index (PCI), movement amplitude and movement frequency. Correlations between interlimb coordination, motor, and cognitive function were examined.ResultsPwMS showed impaired walking capacity but preserved cognitive function. Mixed model analysis revealed a significant effect of group and metronome frequency for PCI, attenuated by the variability in generating knee (antiphase flexion-extension) movements. Movement amplitude was highest at metronome frequency 1.00 Hz. In PwMS significant correlations were found between PCI and cognitive function when performing the task at metronome frequencies 0.75 Hz and 1.50 Hz, as well as motor function at 1.50 Hz.SignificancePwMS had a higher variability in interlimb coordination compared to HC. The most stable interlimb antiphase coordination mode was performed at 1.00 Hz. Significant correlations support the existence of a relationship between information processing speed, as well as walking impairment, with interlimb coordination. While cognitive and motor control are always needed for interlimb coordination movements, associations are strongest in the deviant higher and lower metronome rhythms.  相似文献   
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When making a decision, humans often have to ‘coordinate’—reach the same conclusion—as another individual without explicitly communicating. Relatively, little is known about the neural basis for coordination. Moreover, previous fMRI investigations have supported conflicting hypotheses. One account proposes that individuals coordinate using a ‘gut feeling’ and that this is supported by insula recruitment. Another account proposes that individuals recruit strategic decision-making mechanisms in prefrontal cortex in order to coordinate. We investigate the neural basis for coordination in individuals with behavioral-variant frontotemporal dementia (bvFTD) who have limitations in social decision-making associated with disease in prefrontal cortex. We demonstrate that bvFTD are impaired at establishing a focal point in a semantic task (e.g. ‘Tell me any boy''s name’) that requires coordination relative to a similar, control semantic task that does not. Additionally, coordination limitations in bvFTD are related to cortical thinning in prefrontal cortex. These findings are consistent with behavioral economic models proposing that, beyond a ‘gut feeling’, strategic decision-making contributes to the coordination process, including a probabilistic mechanism that evaluates the salience of a response (e.g. is ‘John’ a frequent boy''s name), a hierarchical mechanism that iteratively models an opponent''s likely response and a mechanism involved in social perspective taking.  相似文献   
46.
Most physiological and biotechnological processes rely on molecular recognition between chiral (handed) molecules. Manmade homogeneous catalysts and enzymes offer complementary means for producing enantiopure (single-handed) compounds. As the subtle details that govern chiral discrimination are difficult to predict, improving the performance of such catalysts often relies on trial-and-error procedures. Homogeneous catalysts are optimized by chemical modification of the chiral environment around the metal center. Enzymes can be improved by modification of gene encoding the protein. Incorporation of a biotinylated organometallic catalyst into a host protein (avidin or streptavidin) affords versatile artificial metalloenzymes for the reduction of ketones by transfer hydrogenation. The boric acid.formate mixture was identified as a hydrogen source compatible with these artificial metalloenzymes. A combined chemo-genetic procedure allows us to optimize the activity and selectivity of these hybrid catalysts: up to 94% (R) enantiomeric excess for the reduction of p-methylacetophenone. These artificial metalloenzymes display features reminiscent of both homogeneous catalysts and enzymes.  相似文献   
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Objective: Urban, minority, and disadvantaged youth with asthma frequently use emergency departments (EDs) for episodic asthma care instead of their primary care providers (PCPs). We sought to increase the rate of guardians' identification of the PCP as the source of asthma care for their children through integrated electronic health records and care coordination. Methods: In this prospective cohort study, we implemented an electronic communication process between an asthma specialty clinic and PCPs coupled with short-term care coordination in sample of youth aged 2–12 years with asthma and surveyed their guardians at baseline and 3 and 6 months after the intervention. Results: Guardians of 50 children (median age 5.8 years, 64% male, 98% African American, 94% public insurance) were enrolled. Compared to baseline, at 3 and 6 months after the intervention, significantly more guardians reported that the PCP was their child's primary asthma health care provider [70% at baseline, 85% at 3 months, 83% at 6 months (time averaged adjusted OR 77.4, 95% CI 3.0, 2027.1]. Further, significantly more guardians reported that they took their child to the PCP when the child experienced problems with his/her asthma [16% at baseline, 35% at 3 months, 41% at 6 months (time averaged adjusted odds ratio (OR) 10.6, 95% CI 2.7, 41.7]. Conclusion: Care in a subspecialty asthma clinic augmented by electronic communication with PCPs and short term care coordination was associated with significantly improved identification of PCPs as the primary source of asthma care in a cohort of urban minority youth.  相似文献   
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[Purpose] The purpose of this study was to identify changes in the thicknesses of the cervical flexors according to eye coordination during deep cervical flexor training. [Subjects and Methods] Twenty normal adults were randomly selected, and during their deep cervical flexor training and eye tracking, the thicknesses of the longus colli and the sternocleidomastoid were measured using ultrasonic waves. [Results] The thickness of the longus colli statistically significantly increased when deep cervical flexor training and eye coordination were performed simultaneously. However, the thickness of the sternocleidomastoid did not show statistically significant differences according to eye coordination. [Conclusion] Eye coordination during deep cervical flexor training is likely to increase the thickness of the longus colli selectively.  相似文献   
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