http://pages.stat.wisc.edu/~mchung/teaching/MIA/reading/DTI.alexander.2007.pdf

Diffusion Tensor Imaging of the Brain

https://wiki.biac.duke.edu/lib/exe/fetch.php?media=biac:jones_etal_2012_the_do_s_and_don_ts_of_diffusion_mri.pdf

White matter integrity, fiber count, and other fallacies: The do's and don'ts of diffusion MRI

Diffusion tensor imaging detects and differentiates axon and myelin degeneration in mouse optic nerve after retinal ischemia.

https://inst.eecs.berkeley.edu/~cs182/sp07/readings/Mori_Neuron_DTI_2006.pdf

Principles of Diffusion Tensor Imaging and Its Applications to Basic Neuroscience Research

Demyelination increases radial diffusivity in corpus callosum of mouse brain.

Dysmyelination Revealed through MRI as Increased Radial (but Unchanged Axial) Diffusion of Water

A fMRI study of brain activations during non-noxious and noxious electrical stimulation of the sciatic nerve of rats

Background and Purpose— Angiogenesis occurs after cerebral ischemia, but the relationship between angiogenesis and cerebral hemodynamic change is unknown. The aim of the present study was to investigate the relationship between ischemia-induced angiogenesis and hemodynamics in a well-defined 3-vessel occlusion model of the rat by using diffusion- (DWI), perfusion-, and T2-weighted MRI (T2WI). Methods— Rats were subjected to 60 minutes of transient middle cerebral artery occlusion or sham operation. DWI and T2WI were used to characterize the extent of the ischemic lesion from 4.5 hours to 14 days after reperfusion. A flow-sensitive alternating inversion recovery method and dynamic susceptibility contrast MRI were used to evaluate the temporal changes in relative cerebral blood flow (CBF) and cerebral blood volume (CBV), respectively. Rats were randomly selected and killed at each time point for investigation of vascular density and for hematoxylin-eosin staining. Results— Ischemic lesions developed in the ...

Dynamic changes in cerebral blood flow and angiogenesis after transient focal cerebral ischemia in rats. Evaluation with serial magnetic resonance imaging.

Neuroprotective effect of lamotrigine and MK-801 on rat brain lesions induced by 3-nitropropionic acid: evaluation by magnetic resonance imaging and in vivo proton magnetic resonance spectroscopy

Tie-1 and Tie-2 are receptor tyrosine kinases (RTKs) that are exclusively expressed in endothelial cells and play important roles in endothelial cell biology. The authors have reported previously the temporal profiles of Tie-1 and Tie-2 mRNA expression after focal cerebral ischemia–reperfusion. In the current study, the localization of Tie-1/Tie-2 mRNA and proteins were further investigated in the same focal ischemia model. In situ hybridization showed that, after 60-minute ischemia and 72-hour reperfusion, both Tie-1 and Tie-2 mRNA appeared as capillary-like structures in the ischemic middle cerebral artery (MCA) cortex. Western blot analysis showed a biphasic expression of Tie-1 protein in the same region. The first peak, spanning the ischemic and early reperfusion period, was of low intensity and short-lived. The second peak was of greater intensity and spanning the period from 72 to 168 hours after reperfusion. Similarly, Tie-2 expression at the protein level also exhibited a biphasic pattern. Immunohistochemical studies, after 72 hours of reperfusion, showed that although Tie-1 and Tie-2 were detected within the ischemic cortex, they actually were expressed in different populations of endothelial cells in different regions. In agreement with the in situ hybridization study, Tie-1 immunoreactivity appeared as capillary-like structures in cortical layers 2 to 4. Similar capillary-like appearance of Tie-2 immunoreactivity was noted in the outer cortical layers. In addition, Tie-2 immunoreactivity also was observed in cortical layer 6b, where de novo large vessel formation was noted. Cellular colocalization experiments revealed that Tie-2 is expressed in proximity to its antagonist, Angpo-2, as well as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) in cortical layer 1, where active vessel remodeling was noted. Interestingly, bFGF only partially colocalized with VEGF, suggesting differential roles for these angiogenic factors during vessel remodeling. Tie-1 protein, to a lesser degree, also colocalized with Angpo-2, bFGF, and VEGF in cortical layer 1. Magnetic resonance imaging (MRI) showed increased regional cerebral blood flow (CBF) corresponding to the expression of these angiogenesis gene products. Together, these findings suggest that the evolving expression of angiogenesis genes underlie the robust vascular remodeling after ischemia and reperfusion.

Chen Chang

Papers

Dysmyelination Revealed through MRI as Increased Radial (but Unchanged Axial) Diffusion of Water

A fMRI study of brain activations during non-noxious and noxious electrical stimulation of the sciatic nerve of rats

Dynamic changes in cerebral blood flow and angiogenesis after transient focal cerebral ischemia in rats. Evaluation with serial magnetic resonance imaging.

Neuroprotective effect of lamotrigine and MK-801 on rat brain lesions induced by 3-nitropropionic acid: evaluation by magnetic resonance imaging and in vivo proton magnetic resonance spectroscopy

Induction of Tie-1 and Tie-2 receptor protein expression after cerebral ischemia-reperfusion.