visualization-3d-white-adipose-tissue-structure-using-whole-mount

Visualization of 3D White Adipose Tissue Structure Using Whole-mount Staining

Adipose tissue is an important metabolic organ with high plasticity and is responsive to environmental stimuli and nutrient status. As such, various ...

The Hospital for Sick Children

Emergency Department (ED) student-based research assistant programs have been shown to be effective in enrolling patients when the students receive university course credit or pay. However, the impact on research outcomes when university students act as volunteers in this role is relatively unknown.

The effectiveness of a student volunteer program for research in a pediatric Emergency Department.

Emergency departments (EDs) have utilized university student volunteers to facilitate enrollment of patients into prospective studies; however, the impact of this experience on participant careers is relatively unknown.

The professional benefits for volunteer research assistants in a pediatric emergency department.

Physical exercise, besides improving cognitive and mental health, is known to cause structural changes in the brain. Understanding the structural changes that occur with exercise as well as the neuroanatomical correlates of a predisposition for exercise is important for understanding human health. This study used high-resolution 3D MR imaging, in combination with deformation-based morphometry, to investigate the macroscopic changes in brain structure that occur in healthy adult mice following four weeks of voluntary exercise. We found that exercise induced changes in multiple brain structures that are involved in motor function and learning and memory including the hippocampus, dentate gyrus, stratum granulosum of the dentate gyrus, cingulate cortex, olivary complex, inferior cerebellar peduncle and regions of the cerebellum. In addition, a number of brain structures, including the hippocampus, striatum and pons, when measured on MRI prior to the start of exercise were highly predictive of subsequent exercise activity. Exercise tended to normalize these pre-existing differences between mice.

MRI-detectable changes in mouse brain structure induced by voluntary exercise.

Behavior depends on coordinated activity across multiple brain regions. Within such networks, highly connected hub regions are assumed to disproportionately influence behavioral output, although this hypothesis has not been systematically evaluated. Previously, by mapping brain-wide expression of the activity-regulated gene c-fos, we identified a network of brain regions co-activated by fear memory. To test the hypothesis that hub regions are more important for network function, here, we simulated node deletion in silico in this behaviorally defined functional network. Removal of high degree nodes produced the greatest network disruption (e.g., reduction in global efficiency). To test these predictions in vivo, we examined the impact of post-training chemogenetic silencing of different network nodes on fear memory consolidation. In a series of independent experiments encompassing 25% of network nodes (i.e., 21/84 brain regions), we found that node degree accurately predicted observed deficits in memory consolidation, with silencing of highly connected hubs producing the largest impairments.

Article	Year
The effectiveness of a student volunteer program for research in a pediatric Emergency Department. The Journal of emergency medicine\| PubMed ID: 25271177	2015
The professional benefits for volunteer research assistants in a pediatric emergency department. The Journal of emergency medicine\| PubMed ID: 25271184	2015
MRI-detectable changes in mouse brain structure induced by voluntary exercise. NeuroImage\| PubMed ID: 25800209	2015
Chemogenetic Interrogation of a Brain-wide Fear Memory Network in Mice. Neuron\| PubMed ID: 28426969	2017

Patrick E. Steadman

Biography

JoVE Journal Publications

Other Publications