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831.
Hippocampi are asymmetrical in children and adults, where the right hippocampus is larger. To date, no literature has confirmed that hippocampal asymmetry is evident at birth. Furthermore, gender differences have been observed in normal hippocampal asymmetry, but this has not been examined in neonates. Stress, injury, and lower IQ have been associated with alterations to hippocampal asymmetry. These same factors often accompany preterm birth. Therefore, prematurity is possibly associated with altered hippocampal asymmetry. There were three aims of this study: First, we assessed whether hippocampi were asymmetrical at birth, second whether there was a gender effect on hippocampal asymmetry, and third whether the stress of preterm birth altered hippocampal asymmetry. This study utilized volumetric magnetic resonance imaging to compare left and right hippocampal volumes in 32 full-term and 184 preterm infants at term. Full-term infants demonstrated rightward hippocampal asymmetry, as did preterm infants. In the case of preterm infants, hippocampal asymmetry was proportional to total hemispheric asymmetry. This study is the first to demonstrate that the normal pattern of hippocampal asymmetry is present this early in development. We did not find gender differences in hippocampal asymmetry at term. Preterm infants tended to have less asymmetrical hippocampi than full-term infants, a difference which became significant after correcting for hemispheric brain tissue volumes. This study may suggest that hippocampal asymmetry develops in utero and is maintained into adulthood in infants with a normal neurological course. 相似文献
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834.
This systematic review evaluates assessments used to discriminate, predict, or evaluate the motor development of preterm infants during the first year of life. Eighteen assessments were identified; nine met the inclusion criteria. The Alberta Infant Motor Scale (AIMS), Bayley Scale of Infant and Toddler Development -- Version III, Peabody Developmental Motor Scales -- Version 2, Test of Infant Motor Performance (TIMP), and Toddler and Infant Motor Examination have good discriminative validity when examined in large populations. The AIMS, Prechtl's Assessment of General Movements (GMs), Neuro Sensory Motor Development Assessment (NSMDA), and TIMP were designed for preterm infants and are able to detect more subtle changes in movement quality. The best predictive assessment tools are age dependent: GMs, the Movement Assessment of Infants, and TIMP are strongest in early infancy (age 4 mo or less) and the AIMS and NSMDA are better at older ages (8-12 mo). The TIMP is the only tool that has demonstrated a difference between groups in response to intervention in two randomized controlled trials. The AIMS, TIMP, and GMs demonstrated the highest levels of overall reliability (interrater and intrarater intraclass correlation coefficient or kappa>0.85). Selection of motor assessment tools during the first year of life for infants born preterm will depend on the intended purpose of their use for discrimination, prediction, and/or evaluation. 相似文献
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836.
Inder TE Hunt RW Morley CJ Coleman L Stewart M Doyle LW Jacobs SE 《The Journal of pediatrics》2004,145(6):835-837
Twenty-six infants with hypoxic-ischemic encephalopathy (HIE) were randomized to normothermia or to systemic hypothermia. The hypothermia group had less cortical gray matter signal abnormality on magnetic resonance imaging (MRI) (1/12 vs 7/14 infants in the normothermic group; P = .036), which may indicate differing regional benefit from systemic hypothermia. 相似文献
837.
Lian van der Krieke Ando C Emerencia Nynke Boonstra Lex Wunderink Peter de Jonge Sjoerd Sytema 《Journal of medical Internet research》2013,15(10)
Background
Mental health policy makers encourage the development of electronic decision aids to increase patient participation in medical decision making. Evidence is needed to determine whether these decision aids are helpful in clinical practice and whether they lead to increased patient involvement and better outcomes.Objective
This study reports the outcome of a randomized controlled trial and process evaluation of a Web-based intervention to facilitate shared decision making for people with psychotic disorders.Methods
The study was carried out in a Dutch mental health institution. Patients were recruited from 2 outpatient teams for patients with psychosis (N=250). Patients in the intervention condition (n=124) were provided an account to access a Web-based information and decision tool aimed to support patients in acquiring an overview of their needs and appropriate treatment options provided by their mental health care organization. Patients were given the opportunity to use the Web-based tool either on their own (at their home computer or at a computer of the service) or with the support of an assistant. Patients in the control group received care as usual (n=126). Half of the patients in the sample were patients experiencing a first episode of psychosis; the other half were patients with a chronic psychosis. Primary outcome was patient-perceived involvement in medical decision making, measured with the Combined Outcome Measure for Risk Communication and Treatment Decision-making Effectiveness (COMRADE). Process evaluation consisted of questionnaire-based surveys, open interviews, and researcher observation.Results
In all, 73 patients completed the follow-up measurement and were included in the final analysis (response rate 29.2%). More than one-third (48/124, 38.7%) of the patients who were provided access to the Web-based decision aid used it, and most used its full functionality. No differences were found between the intervention and control conditions on perceived involvement in medical decision making (COMRADE satisfaction with communication: F1,68=0.422, P=.52; COMRADE confidence in decision: F1,67=0.086, P=.77). In addition, results of the process evaluation suggest that the intervention did not optimally fit in with routine practice of the participating teams.Conclusions
The development of electronic decision aids to facilitate shared medical decision making is encouraged and many people with a psychotic disorder can work with them. This holds for both first-episode patients and long-term care patients, although the latter group might need more assistance. However, results of this paper could not support the assumption that the use of electronic decision aids increases patient involvement in medical decision making. This may be because of weak implementation of the study protocol and a low response rate.Trial Registration
Dutch Trial Register (NTR) trial number: 10340; http://www.trialregister.nl/trialreg/admin/rctsearch.asp?Term=10340 (Archived by WebCite at http://www.webcitation.org/6Jj5umAeS). 相似文献838.
Lex J. Gmez James C. Dooley Greta Sokoloff Mark S. Blumberg 《The Journal of neuroscience》2021,41(15):3418
It is generally supposed that primary motor cortex (M1) receives somatosensory input predominantly via primary somatosensory cortex (S1). However, a growing body of evidence indicates that M1 also receives direct sensory input from the thalamus, independent of S1; such direct input is particularly evident at early ages before M1 contributes to motor control. Here, recording extracellularly from the forelimb regions of S1 and M1 in unanesthetized rats at postnatal day (P)8 and P12, we compared S1 and M1 responses to self-generated (i.e., reafferent) forelimb movements during active sleep and wake, and to other-generated (i.e., exafferent) forelimb movements. At both ages, reafferent responses were processed in parallel by S1 and M1; in contrast, exafferent responses were processed in parallel at P8 but serially, from S1 to M1, at P12. To further assess this developmental difference in processing, we compared exafferent responses to proprioceptive and tactile stimulation. At both P8 and P12, proprioceptive stimulation evoked parallel responses in S1 and M1, whereas tactile stimulation evoked parallel responses at P8 and serial responses at P12. Independent of the submodality of exafferent stimulation, pairs of S1-M1 units exhibited greater coactivation during active sleep than wake. These results indicate that S1 and M1 independently develop somatotopy before establishing the interactive relationship that typifies their functionality in adults.SIGNIFICANCE STATEMENT Learning any new motor task depends on the ability to use sensory information to update motor outflow. Thus, to understand motor learning, we must also understand how animals process sensory input. Primary somatosensory cortex (S1) and primary motor cortex (M1) are two interdependent structures that process sensory input throughout life. In adults, the functional relationship between S1 and M1 is well established; however, little is known about how S1 and M1 begin to transmit or process sensory information in early life. In this study, we investigate the early development of S1 and M1 as a sensory processing unit. Our findings provide new insights into the fundamental principles of sensory processing and the development of functional connectivity between these important sensorimotor structures. 相似文献
839.
de Heer LM Budde RP Vonken EJ Baaijens FP Gründeman PF van Herwerden LA Hoerstrup SP Kluin J 《The Annals of thoracic surgery》2011,(1):344-345
Tissue-engineered heart valves (TEHV) are being explored as an alternative to conventional heart valve prostheses. Using the classic tissue engineering paradigm, a stented tri-leaflet valve is fabricated. Subsequently, the construct is implanted into the pulmonary position in a sheep. Follow-up by means of computed tomography, magnetic resonance imaging, and echocardiography was used to assess tissue formation. After 4 weeks, the scaffold of the TEHV has degraded and new tissue is formed. However, small areas without tissue formation were present at macroscopic inspection. This phenomenon was only visible on computed tomographic images. Therefore, computed tomography appears a promising technique for in vivo follow-up of tissue formation in tissue-engineered heart valves. 相似文献