6 results on '"Grohn, O"'
Search Results
2. Cortical spreading depression induces oxidative stress in the trigeminal nociceptive system
- Author
-
Shatillo, A., Koroleva, K., Giniatullina, R., Naumenko, N., Slastnikova, A.A., Aliev, R.R., Bart, G., Atalay, M., Gu, C., Khazipov, R., Davletov, B., Grohn, O., and Giniatullin, R.
- Published
- 2013
- Full Text
- View/download PDF
3. Quantitative diffusion MRI of hippocampus as a surrogate marker for post-traumatic epileptogenesis
- Author
-
Kharatishvili, I., primary, Immonen, R., additional, Grohn, O., additional, and Pitkanen, A., additional
- Published
- 2007
- Full Text
- View/download PDF
4. Steerable3D: An ImageJ plugin for neurovascular enhancement in 3-D segmentation
- Author
-
Olli Gröhn, Alejandra Sierra, Marta Moraschi, Paolo Miocchi, Charles Nicaise, Alessia Cedola, Laura Maugeri, Francesco Brun, Alberto Mittone, Fabio Mangini, Michela Fratini, Lorenzo Massimi, Inna Bukreeva, Jussi Tohka, Federico Giove, Alberto Bravin, Eleonora Stefanutti, Ali Abdollahzadeh, Miocchi, P, Sierra, A, Maugeri, L, Stefanutti, E, Abdollahzadeh, A, Mangini, F, Moraschi, M, Bukreeva, I, Massimi, L, Brun, F, Tohka, J, Grohn, O, Mittone, A, Bravin, A, Nicaise, C, Giove, F, Cedola, A, Fratini, M, Miocchi, P., Sierra, A., Maugeri, L., Stefanutti, E., Abdollahzadeh, A., Mangini, F., Moraschi, M., Bukreeva, I., Massimi, L., Brun, F., Tohka, J., Grohn, O., Mittone, A., Bravin, A., Nicaise, C., Giove, F., Cedola, A., and Fratini, M.
- Subjects
Computer science ,Gaussian ,Biophysics ,General Physics and Astronomy ,Image processing ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,Imaging, Three-Dimensional ,Contrast-to-noise ratio ,Steerable filter ,Image noise ,Image Processing, Computer-Assisted ,X ray phase contrast tomography ,Radiology, Nuclear Medicine and imaging ,Segmentation ,Orientation (computer vision) ,business.industry ,Pattern recognition ,General Medicine ,Filter (signal processing) ,3D steerable filter ,Vascular network ,030220 oncology & carcinogenesis ,symbols ,Artificial intelligence ,business ,Algorithms - Abstract
Purpose Image processing plays a fundamental role in the study of central nervous system, for example in the analysis of the vascular network in neurodegenerative diseases. Synchrotron X-ray Phase-contrast micro-Tomography (SXPCT) is a very attractive method to study weakly absorbing samples and features, such as the vascular network in the spinal cord (SC). However, the identification and segmentation of vascular structures in SXPCT images is seriously hampered by the presence of image noise and strong contrast inhomogeneities, due to the sensitivity of the technique to small electronic density variations. In order to help with these tasks, we implemented a user-friendly ImageJ plugin based on a 3D Gaussian steerable filter, tuned up for the enhancement of tubular structures in SXPCT images. Methods The developed 3D Gaussian steerable filter plugin for ImageJ is based on the steerability properties of Gaussian derivatives. We applied it to SXPCT images of ex-vivo mouse SCs acquired at different experimental conditions. Results The filter response shows a strong amplification of the source image contrast-to-background ratio (CBR), independently of structures orientation. We found that after the filter application, the CBR ratio increases by a factor ranging from ~6 to ~60. In addition, we also observed an increase of 35% of the contrast to noise ratio in the case of injured mouse SC. Conclusion The developed tool can generally facilitate the detection/segmentation of capillaries, veins and arteries that were not clearly observable in non-filtered SXPCT images. Its systematic application could allow obtaining quantitative information from pre-clinical and clinical images.
- Published
- 2021
5. Imaging biomarkers of epileptogenecity after traumatic brain injury - Preclinical frontiers.
- Author
-
Immonen R, Harris NG, Wright D, Johnston L, Manninen E, Smith G, Paydar A, Branch C, and Grohn O
- Subjects
- Animals, Brain Injuries, Traumatic complications, Disease Progression, Encephalitis diagnostic imaging, Encephalitis etiology, Epilepsy, Post-Traumatic etiology, Humans, Magnetic Resonance Imaging, Biomarkers, Brain diagnostic imaging, Brain Injuries, Traumatic diagnostic imaging, Epilepsy, Post-Traumatic diagnostic imaging, Neuroimaging
- Abstract
Posttraumatic epilepsy (PTE) is a major neurodegenerative disease accounting for 20% of symptomatic epilepsy cases. A long latent phase offers a potential window for prophylactic treatment strategies to prevent epilepsy onset, provided that the patients at risk can be identified. Some promising imaging biomarker candidates for posttraumatic epileptogenesis have been identified, but more are required to provide the specificity and sensitivity for accurate prediction. Experimental models and preclinical longitudinal, multimodal imaging studies allow follow-up of complex cascade of events initiated by traumatic brain injury, as well as monitoring of treatment effects. Preclinical imaging data from the posttraumatic brain are rich in information, yet examination of their specific relevance to epilepsy is lacking. Accumulating evidence from ongoing preclinical studies in TBI support insight into processes involved in epileptogenesis, e.g. inflammation and changes in functional and structural brain-wide connectivity. These efforts are likely to produce both new biomarkers and treatment targets for PTE., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
6. Decreased resting functional connectivity after traumatic brain injury in the rat.
- Author
-
Mishra AM, Bai X, Sanganahalli BG, Waxman SG, Shatillo O, Grohn O, Hyder F, Pitkänen A, and Blumenfeld H
- Subjects
- Animals, Electrodes, Magnetic Resonance Imaging, Male, Rats, Rats, Sprague-Dawley, Seizures physiopathology, Brain Injuries physiopathology
- Abstract
Traumatic brain injury (TBI) contributes to about 10% of acquired epilepsy. Even though the mechanisms of post-traumatic epileptogenesis are poorly known, a disruption of neuronal networks predisposing to altered neuronal synchrony remains a viable candidate mechanism. We tested a hypothesis that resting state BOLD-fMRI functional connectivity can reveal network abnormalities in brain regions that are connected to the lesioned cortex, and that these changes associate with functional impairment, particularly epileptogenesis. TBI was induced using lateral fluid-percussion injury in seven adult male Sprague-Dawley rats followed by functional imaging at 9.4T 4 months later. As controls we used six sham-operated animals that underwent all surgical operations but were not injured. Electroencephalogram (EEG)-functional magnetic resonance imaging (fMRI) was performed to measure resting functional connectivity. A week after functional imaging, rats were implanted with bipolar skull electrodes. After recovery, rats underwent pentyleneterazol (PTZ) seizure-susceptibility test under EEG. For image analysis, four pairs of regions of interests were analyzed in each hemisphere: ipsilateral and contralateral frontal and parietal cortex, hippocampus, and thalamus. High-pass and low-pass filters were applied to functional imaging data. Group statistics comparing injured and sham-operated rats and correlations over time between each region were calculated. In the end, rats were perfused for histology. None of the rats had epileptiform discharges during functional imaging. PTZ-test, however revealed increased seizure susceptibility in injured rats as compared to controls. Group statistics revealed decreased connectivity between the ipsilateral and contralateral parietal cortex and between the parietal cortex and hippocampus on the side of injury as compared to sham-operated animals. Injured animals also had abnormal negative connectivity between the ipsilateral and contralateral parietal cortex and other regions. Our data provide the first evidence on abnormal functional connectivity after experimental TBI assessed with resting state BOLD-fMRI.
- Published
- 2014
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.