1.Sporadic Congenital Oculomotor Apraxia Associated with Ataxia.
Samin HONG ; Seunghan HAN ; Jongbok LEE
Journal of the Korean Ophthalmological Society 2005;46(8):1368-1373
PURPOSE: To evaluate the natural clinical course of sporadic congenital oculomotor apraxia associated with ataxia. METHODS: In a retrospective study from June 1994 to March 2004, 3 patients with sporadic congenital oculomotor apraxia associated with ataxia were evaluated. Oculomotor apraxia and ataxia were checked. RESULTS: The three patients with sporadic congenital oculomotor apraxia associated with ataxia showed a decrease in head thrust which can be found specifically in oculomotor apraxia, and an improvement of oculomotor apraxia and ataxia over the 10-year observation period. CONCLUSIONS: A favorable natural clinical course can be expected in a case of sporadic congenital oculomotor apraxia associated with ataxia in the absence of any clinical evidence of inheritance or genetic abnormality.
Apraxias*
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Ataxia*
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Head
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Humans
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Retrospective Studies
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Wills
2.NADPH Oxidase 4-mediated AlveolarMacrophage Recruitment to Lung Attenuates Neutrophilic Inflammation in Staphylococcus aureus Infection
Seunghan HAN ; Sungmin MOON ; Youn Wook CHUNG ; Ji-Hwan RYU
Immune Network 2023;23(5):e42-
When the lungs are infected with bacteria, alveolar macrophages (AMs) are recruited to the site and play a crucial role in protecting the host by reducing excessive lung inflammation.However, the regulatory mechanisms that trigger the recruitment of AMs to lung alveoli during an infection are still not fully understood. In this study, we identified a critical role for NADPH oxidase 4 (NOX4) in the recruitment of AMs during Staphylococcus aureus lung infection. We found that NOX4 knockout (KO) mice showed decreased recruitment of AMs and increased lung neutrophils and injury in response to S. aureus infection compared to wildtype (WT) mice. Interestingly, the burden of S. aureus in the lungs was not different between NOX4 KO and WT mice. Furthermore, we observed that depletion of AMs in WT mice during S. aureus infection increased the number of neutrophils and lung injury to a similar level as that observed in NOX4 KO mice. Additionally, we found that expression of intercellular adhesion molecule-1 (ICAM1) in NOX4 KO mice-derived lung endothelial cells was lower than that in WT mice-derived endothelial cells. Therefore, we conclude that NOX4 plays a crucial role in inducing the recruitment of AMs by controlling ICAM1 expression in lung endothelial cells, which is responsible for resolving lung inflammation during acute S. aureus infection.
3.Spine Computed Tomography to Magnetic Resonance Image Synthesis Using Generative Adversarial Networks : A Preliminary Study
Jung Hwan LEE ; In Ho HAN ; Dong Hwan KIM ; Seunghan YU ; In Sook LEE ; You Seon SONG ; Seongsu JOO ; Cheng-Bin JIN ; Hakil KIM
Journal of Korean Neurosurgical Society 2020;63(3):386-396
Objective:
: To generate synthetic spine magnetic resonance (MR) images from spine computed tomography (CT) using generative adversarial networks (GANs), as well as to determine the similarities between synthesized and real MR images.
Methods:
: GANs were trained to transform spine CT image slices into spine magnetic resonance T2 weighted (MRT2) axial image slices by combining adversarial loss and voxel-wise loss. Experiments were performed using 280 pairs of lumbar spine CT scans and MRT2 images. The MRT2 images were then synthesized from 15 other spine CT scans. To evaluate whether the synthetic MR images were realistic, two radiologists, two spine surgeons, and two residents blindly classified the real and synthetic MRT2 images. Two experienced radiologists then evaluated the similarities between subdivisions of the real and synthetic MRT2 images. Quantitative analysis of the synthetic MRT2 images was performed using the mean absolute error (MAE) and peak signal-to-noise ratio (PSNR).
Results:
: The mean overall similarity of the synthetic MRT2 images evaluated by radiologists was 80.2%. In the blind classification of the real MRT2 images, the failure rate ranged from 0% to 40%. The MAE value of each image ranged from 13.75 to 34.24 pixels (mean, 21.19 pixels), and the PSNR of each image ranged from 61.96 to 68.16 dB (mean, 64.92 dB).
Conclusion
: This was the first study to apply GANs to synthesize spine MR images from CT images. Despite the small dataset of 280 pairs, the synthetic MR images were relatively well implemented. Synthesis of medical images using GANs is a new paradigm of artificial intelligence application in medical imaging. We expect that synthesis of MR images from spine CT images using GANs will improve the diagnostic usefulness of CT. To better inform the clinical applications of this technique, further studies are needed involving a large dataset, a variety of pathologies, and other MR sequence of the lumbar spine.