ABSTRACT
School-age children are in a specific development stage corresponding to juvenility, when the white matter of the brain experiences ongoing maturation. Diffusion-weighted magnetic resonance imaging (DWI), especially diffusion tensor imaging (DTI), is extensively used to characterize the maturation by assessing white matter properties in vivo. In the analysis of DWI data, spatial normalization is crucial for conducting inter-subject analyses or linking the individual space with the reference space. Using tensor-based registration with an appropriate diffusion tensor template presents high accuracy regarding spatial normalization. However, there is a lack of a standardized diffusion tensor template dedicated to school-age children with ongoing brain development. Here, we established the school-age children diffusion tensor (SACT) template by optimizing tensor reorientation on high-quality DTI data from a large sample of cognitively normal participants aged 6-12 years. With an age-balanced design, the SACT template represented the entire age range well by showing high similarity to the age-specific templates. Compared with the tensor template of adults, the SACT template revealed significantly higher spatial normalization accuracy and inter-subject coherence upon evaluation of subjects in two different datasets of school-age children. A practical application regarding the age associations with the normalized DTI-derived data was conducted to further compare the SACT template and the adult template. Although similar spatial patterns were found, the SACT template showed significant effects on the distributions of the statistical results, which may be related to the performance of spatial normalization. Looking forward, the SACT template could contribute to future studies of white matter development in both healthy and clinical populations. The SACT template is publicly available now ( https://figshare.com/articles/dataset/SACT_template/14071283 ).
ABSTRACT
Objective To evaluate the relationship between different levels of central venous pres-sure (CVP) and blood loss during pediatric living donor liver transplantation (LDLT). Methods Pediat-ric patients underwent LDLT in Renji Hospital from 2006 to August 10, 2016 were retrospectively reviewed. The patients were divided into 2 groups according to the different CVP levels before peritoneum closure:central venous pressure<10 mmHg group ( group L) and CVP≥10 mmHg group ( group H) . The primary outcome measure was intraoperative blood loss. The secondary outcome measures were duration of mechani-cal ventilation in intensive care unit (ICU), duration of ICU stay, length of postoperative hospital stay, intraoperative blood loss, intraoperative blood transfusion, intraoperative volume of liquid infused, opera-tion time and anesthesia time. Results A total of 442 pediatric patients were enrolled in this study, with 209 cases in group L and 233 cases in group H. Compared with group H, the intraoperative blood loss was significantly decreased, the anesthesia time, operation time and length of postoperative hospital stay were shortened ( P<0. 05) , and no significant change was found in intraoperative blood transfusion, intraopera-tive volume of liquid infused, duration of mechanical ventilation in ICU or duration of ICU stay in group L ( P>0. 05) . Conclusion Maintaining intraoperative CVP<10 mmHg can markedly reduce the blood loss during LDLT and is helpful for postoperative recovery in pediatric patients.
ABSTRACT
Granger causality model is an analysis method that requires no priori knowledge and emphasizes time sequence. Such model applied to brain effective connectivity network can reflect the directional connectivity among brain regions or neurons. This paper reviews the principle of Granger causality model, basic test steps and improved models, analyzes and discusses applications and existing problems of Granger causality model in brain effective connectivity network.
Subject(s)
Humans , Brain , Physiology , Brain Mapping , Computer Simulation , Models, Neurological , Neurons , PhysiologyABSTRACT
Aim To investigate the protective effects of high concentration fentanyl on the brain slice injury induced by oxygen glucose deprivation(OGD).Methods Rat brain slices were made and randomly assigned to four groups:control(n=10),OGD(n=10),fentanyl 50 ?g?L~(-1)(F_(50),n=10) and fentanyl 500 ?g?L~(-1)(F_(500),n=10).Changes of the neuron injury and apoptosis were observed with TTC staining,LDH releases,TUNEL staining,immunohistochemistry and electromicroscope.In addition,changes of intracellular calcium were measured with confocal laser-scanning microscopy.Results F_(50) and F_(500) attenuated the decrease of TTC staining and the increase of LDH release induced by OGD in brain slices.Neuronal apoptosis and changes of neuronal ultrastructures were attenuated by F_(50) and F_(500).Bcl-2 and Bax protein expressions were increased after OGD.Bax protein expression was decreased by F_(50) and F_(500),while Bcl-2 protein expression was increased by F_(50)and F_(500).Intracellular calcium concentration was increased by OGD and then it was lowered by F_(50) and F_(500).The protective effects of F_(50) were more obvious than that of F_(500).Conclusions High concentrations of fentanyl have neuron protective effects against OGD injury in rat brain slices,and fentanyl 50 ?g?L~(-1) has more obvious protective effects than fentanyl 500 ?g?L~(-1).