Heterogeneity of MR signal intensity mapped onto brain surface models

Aim: To develop a modular software pipeline for robustly extracting 3D brain-surface models from MRIs for visualization or printing. No other end-to-end pipeline specialized for neuroimaging does this directly with an interchangeable combination of methods. Materials & methods: A software application was developed to dynamically generate Nipype workflows using interfaces from the Analysis of Functional NeuroImages, Advanced Normalization Tools, FreeSurfer, BrainSuite, Nighres and the FMRIB Software Library suites. The application was deployed for public use via the LONI pipeline environment. Results: In a small, head-to-head comparison test, a pipeline using FreeSurfer for both the skull stripping and cortical-mesh extraction stages earned the highest subjective quality scores. Conclusion: We have deployed a publicly available and modular software tool for extracting 3D models from brain MRIs to use in medical education.

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Analytical Electron Microscopy (AEM) of Meningeal Cells Exposed to Particulate Cobalt During Studies of Experimental Epilepsy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053590 ◽

1982 ◽

Vol 40 ◽

pp. 186-187

Author(s):

R.G. Frederickson ◽

R.G. Ulrich ◽

J.L. Culberson

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Experimental Epilepsy ◽

Metallic Cobalt ◽

Experimental Animals ◽

X Ray ◽

Brain Surface ◽

Meningeal Cells ◽

Analytical Electron ◽

The Brain

Metallic cobalt acts as an epileptogenic agent when placed on the brain surface of some experimental animals. The mechanism by which this substance produces abnormal neuronal discharge is unknown. One potentially useful approach to this problem is to study the cellular and extracellular distribution of elemental cobalt in the meninges and adjacent cerebral cortex. Since it is possible to demonstrate the morphological localization and distribution of heavy metals, such as cobalt, by correlative x-ray analysis and electron microscopy (i.e., by AEM), we are using AEM to locate and identify elemental cobalt in phagocytic meningeal cells of young 80-day postnatal opossums following a subdural injection of cobalt particles.

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Brain surface ependymoma

Neuropathology ◽

10.1046/j.1440-1789.2000.00355.x ◽

2000 ◽

Vol 20 (4) ◽

pp. 315-318 ◽

Cited By ~ 16

Author(s):

Yuichiro Sato ◽

Hidenobu Ochiai ◽

Yuzo Yamakawa ◽

Kazuki Nabeshima ◽

Yujiro Asada ◽

...

Keyword(s):

Brain Surface

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Influence of preoperative statins and aspirin administration on biological and magnetic resonance imaging properties in patients with abdominal aortic aneurysm

VASA ◽

10.1024/0301-1526/a000895 ◽

2020 ◽

pp. 1-9

Author(s):

Milos Sladojevic ◽

Petar Zlatanovic ◽

Zeljka Stanojevic ◽

Igor Koncar ◽

Sasenka Vidicevic ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Abdominal Aortic Aneurysm ◽

Magnetic Resonance ◽

Aortic Aneurysm ◽

Signal Intensity ◽

Psoas Muscle ◽

Resonance Imaging ◽

Maximal Diameter ◽

Aneurysm Wall ◽

Abdominal Aortic

Summary: Background: Main objective of this study was to evaluate the influence of statins and/or acetylsalicylic acid on biochemical characteristics of abdominal aortic aneurysm (AAA) wall and intraluminal thrombus (ILT). Patients and methods: Fifty patients with asymptomatic infrarenal AAA were analyzed using magnetic resonance imaging on T1w sequence. Relative ILT signal intensity (SI) was determined as a ratio between ILT and psoas muscle SI. Samples containing the full ILT thickness and aneurysm wall were harvested from the anterior surface at the level of the maximal diameter. The concentration of enzymes such as matrix metalloproteinase (MMP) 9, MMP2 and neutrophil elastase (NE/ELA) were analyzed in ILT and AAA wall; while collagen type III, elastin and proteoglycan 4 were analyzed in harvested AAA wall. Oxidative stress in the AAA wall was assessed by catalase and malondialdehyde activity in tissue samples. Results: Relative ILT signal intensity (1.09 ± 0.41 vs 0.89 ± 0.21, p = 0.013) were higher in non-statin than in statin group. Patients who were taking aspirin had lower relative ILT area (0.89 ± 0.19 vs 1.13. ± 0.44, p = 0.016), and lower relative ILT signal intensity (0.85 [0.73–1.07] vs 1.01 [0.84–1.19], p = 0.021) compared to non-aspirin group. There were higher concentrations of elastin in AAA wall among patients taking both of aspirin and statins (1.21 [0.77–3.02] vs 0.78 (0.49–1.05) ng/ml, p = 0.044) than in patients who did not take both of these drugs. Conclusions: Relative ILT SI was lower in patients taking statin and aspirin. Combination of antiplatelet therapy and statins was associated with higher elastin concentrations in AAA wall.

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A new technique for the mapping of oxygen tension on the brain surface

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/sj.jcbfm.9591524.0543 ◽

2005 ◽

Vol 25 (1_suppl) ◽

pp. S543-S543

Author(s):

Satoshi Kimura ◽

Keigo Matsumoto ◽

Yoshio Imahori ◽

Katsuyoshi Mineura ◽

Toshiyuki Itoh

Keyword(s):

Oxygen Tension ◽

New Technique ◽

Brain Surface ◽

A New Technique ◽

The Brain

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Cause of increase in signal intensity in T1-weighted images in the striatal region after global ischemia

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/sj.jcbfm.9591524.0341 ◽

2005 ◽

Vol 25 (1_suppl) ◽

pp. S341-S341

Author(s):

Yoshimasa Takeda ◽

Hisami Aoe ◽

Kiyoshi Morita

Keyword(s):

Signal Intensity ◽

Global Ischemia

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Elemental chlorine-free bleaching of North American hardwood kraft pulps: Evaluation of oxidant-reinforced extraction variables on overall bleaching optimization

TAPPI Journal ◽

10.32964/tj12.10.33 ◽

2013 ◽

Vol 12 (10) ◽

pp. 33-41 ◽

Cited By ~ 4

Author(s):

BRIAN N. BROGDON

Keyword(s):

Response Surface ◽

Chlorine Dioxide ◽

North American ◽

Yield Loss ◽

Alkaline Extraction ◽

Kraft Pulps ◽

Pulp Bleaching ◽

Response Surface Models ◽

Elemental Chlorine ◽

Surface Models

This investigation evaluates how higher reaction temperatures or oxidant reinforcement of caustic extraction affects chlorine dioxide consumption during elemental chlorine-free bleaching of North American hardwood pulps. Bleaching data from the published literature were used to develop statistical response surface models for chlorine dioxide delignification and brightening sequences for a variety of hardwood pulps. The effects of higher (EO) temperature and of peroxide reinforcement were estimated from observations reported in the literature. The addition of peroxide to an (EO) stage roughly displaces 0.6 to 1.2 kg chlorine dioxide per kilogram peroxide used in elemental chlorine-free (ECF) bleach sequences. Increasing the (EO) temperature by Δ20°C (e.g., 70°C to 90°C) lowers the overall chlorine dioxide demand by 0.4 to 1.5 kg. Unlike what is observed for ECF softwood bleaching, the presented findings suggest that hot oxidant-reinforced extraction stages result in somewhat higher bleaching costs when compared to milder alkaline extraction stages for hardwoods. The substitution of an (EOP) in place of (EO) resulted in small changes to the overall bleaching cost. The models employed in this study did not take into account pulp bleaching shrinkage (yield loss), to simplify the calculations.

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