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Im C, Park JH, Jeon YM, Kim JG, Jang YS, Lee MH, Jeon WY, Kim JM, Bae TS. Improvement of osseointegration of Ti–6Al–4V ELI alloy orthodontic mini-screws through anodization, cyclic pre-calcification, and heat treatments. Prog Orthod 2022; 23:11. [PMID: 35368222 PMCID: PMC8977256 DOI: 10.1186/s40510-022-00405-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 03/22/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Mini-screws are widely used as temporary anchorages in orthodontic treatment, but have the disadvantage of showing a high failure rate of about 10%. Therefore, orthodontic mini-screws should have high biocompatibility and retention. Previous studies have demonstrated that the retention of mini-screws can be improved by imparting bioactivity to the surface. The method for imparting bioactivity proposed in this paper is to sequentially perform anodization, periodic pre-calcification, and heat treatments with a Ti–6Al–4V ELI alloy mini-screw.
Materials and methods
A TiO2 nanotube-structured layer was formed on the surface of the Ti–6Al–4V ELI alloy mini-screw through anodization in which a voltage of 20 V was applied to a glycerol solution containing 20 wt% H2O and 1.4 wt% NH4F for 60 min. Fine granular calcium phosphate precipitates of HA and octacalcium phosphate were generated as clusters on the surface through the cyclic pre-calcification and heat treatments. The cyclic pre-calcification treatment is a process of immersion in a 0.05 M NaH2PO4 solution and a saturated Ca(OH)2 solution at 90 °C for 1 min each.
Results
It was confirmed that the densely structured protrusions were precipitated, and Ca and P concentrations, which bind and concentrate endogenous bone morphogenetic proteins, increased on the surface after simulated body fluid (SBF) immersion test. In addition, the removal torque of the mini-screw fixed into rabbit tibias for 4 weeks was measured to be 8.70 ± 2.60 N cm.
Conclusions
A noteworthy point in this paper is that the Ca and P concentrations, which provide a scaffold suitable for endogenous bone formation, further increased over time after SBF immersion of the APH group specimens. The other point is that our mini-screws have a significantly higher removal torque compared to untreated mini-screws. These results represent that the mini-screw proposed in this paper can be used as a mini-screw for orthodontics.
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Im C, Shin J, Lee WR, Kim JM. Machine learning-based feature combination analysis for odor-dependent hemodynamic responses of rat olfactory bulb. Biosens Bioelectron 2022; 197:113782. [PMID: 34814029 DOI: 10.1016/j.bios.2021.113782] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 10/19/2021] [Accepted: 11/08/2021] [Indexed: 11/29/2022]
Abstract
Rodents have a well-developed sense of smell and are used to detect explosives, mines, illegal substances, hidden currency, and contraband, but it is impossible to keep their concentration constantly. Therefore, there is an ongoing effort to infer odors detected by animals without behavioral readings with brain-computer interface (BCI) technology. However, the invasive BCI technique has the disadvantage that long-term studies are limited by the immune response and electrode movement. On the other hand, near-infrared spectroscopy (NIRS)-based BCI technology is a non-invasive method that can measure neuronal activity without worrying about the immune response or electrode movement. This study confirmed that the NIRS-based BCI technology can be used as an odor detection and identification from the rat olfactory system. In addition, we tried to present features optimized for machine learning models by extracting six features, such as slopes, peak, variance, mean, kurtosis, and skewness, from the hemodynamic response, and analyzing the importance of individuals or combinations. As a result, the feature with the highest F1-Score was indicated as slopes, and it was investigated that the combination of the features including slopes and mean was the most important for odor inference. On the other hand, the inclusion of other features with a low correlation with slopes had a positive effect on the odor inference, but most of them resulted in insignificant or rather poor performance. The results presented in this paper are expected to serve as a basis for suggesting the development direction of the hemodynamic response-based bionic nose in the future.
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Affiliation(s)
- Changkyun Im
- Bio & Medical Health Division, Korea Testing Laboratory, Seoul, 08389, Republic of Korea
| | - Jaewoo Shin
- Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5S 1A8, Canada; Department of Neurosurgery, Brain Research Institute, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Woo Ram Lee
- Department of Electronic Engineering, Gyeonggi University of Science and Technology, Siheung, 15073, Republic of Korea.
| | - Jun-Min Kim
- Department of Mechanical Systems Engineering Electronics, Hansung University, Seoul, 02876, Republic of Korea.
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3
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Kim JM, Lee WR, Kim JH, Seo JM, Im C. Light-Induced Fluorescence-Based Device and Hybrid Mobile App for Oral Hygiene Management at Home: Development and Usability Study. JMIR Mhealth Uhealth 2020; 8:e17881. [PMID: 33064097 PMCID: PMC7600004 DOI: 10.2196/17881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 06/05/2020] [Accepted: 09/01/2020] [Indexed: 11/13/2022] Open
Abstract
Background Dental diseases can be prevented through the management of dental plaques. Dental plaque can be identified using the light-induced fluorescence (LIF) technique that emits light at 405 nm. The LIF technique is more convenient than the commercial technique using a disclosing agent, but the result may vary for each individual as it still requires visual identification. Objective The objective of this study is to introduce and validate a deep learning–based oral hygiene monitoring system that makes it easy to identify dental plaques at home. Methods We developed a LIF-based system consisting of a device that can visually identify dental plaques and a mobile app that displays the location and area of dental plaques on oral images. The mobile app is programmed to automatically determine the location and distribution of dental plaques using a deep learning–based algorithm and present the results to the user as time series data. The mobile app is also built with convergence of naive and web applications so that the algorithm is executed on a cloud server to efficiently distribute computing resources. Results The location and distribution of users’ dental plaques could be identified via the hand-held LIF device or mobile app. The color correction filter in the device was developed using a color mixing technique. The mobile app was built as a hybrid app combining the functionalities of a native application and a web application. Through the scrollable WebView on the mobile app, changes in the time series of dental plaque could be confirmed. The algorithm for dental plaque detection was implemented to run on Amazon Web Services for object detection by single shot multibox detector and instance segmentation by Mask region-based convolutional neural network. Conclusions This paper shows that the system can be used as a home oral care product for timely identification and management of dental plaques. In the future, it is expected that these products will significantly reduce the social costs associated with dental diseases.
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Affiliation(s)
- Jun-Min Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea.,Department of Electronics and Information Engineering, Hansung University, Seoul, Republic of Korea
| | - Woo Ram Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea.,Department of Electronic Communication Engineering, Gyeonggi University of Science Technology, Siheung, Republic of Korea
| | - Jun-Ho Kim
- Department of Electrical Energy Engineering, Keimyung University, Daegu, Republic of Korea
| | - Jong-Mo Seo
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea
| | - Changkyun Im
- Dental Research Institute, Seoul National University, Seoul, Republic of Korea.,Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul, Republic of Korea
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Lee WR, Im C, Park HY, Seo JM, Kim JM. Fabrication of Convex PDMS-Parylene Microstructures for Conformal Contact of Planar Micro-Electrode Array. Polymers (Basel) 2019; 11:polym11091436. [PMID: 31480664 PMCID: PMC6780241 DOI: 10.3390/polym11091436] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/23/2019] [Accepted: 08/27/2019] [Indexed: 11/16/2022] Open
Abstract
Polymer-based micro-electrode arrays (MEAs) are gaining attention as an essential technology to understand brain connectivity and function in the field of neuroscience. However, polymer based MEAs may have several challenges such as difficulty in performing the etching process, difficulty of micro-pattern generation through the photolithography process, weak metal adhesion due to low surface energy, and air pocket entrapment over the electrode site. In order to compensate for the challenges, this paper proposes a novel MEA fabrication process that is performed sequentially with (1) silicon mold preparation; (2) PDMS replica molding, and (3) metal patterning and parylene insulation. The MEA fabricated through this process possesses four arms with electrode sites on the convex microstructures protruding about 20 μm from the outermost layer surface. The validity of the convex microstructure implementation is demonstrated through theoretical background. The electrochemical impedance magnitude is 204.4 ± 68.1 kΩ at 1 kHz. The feasibility of the MEA with convex microstructures was confirmed by identifying the oscillation in the beta frequency band (13–30 Hz) in the electrocorticography signal of a rat olfactory bulb during respiration. These results suggest that the MEA with convex microstructures is promising for applying to various neural recording and stimulation studies.
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Affiliation(s)
- Woo Ram Lee
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Korea
- Department of Electrical and Computer Engineering, and Institute of Engineering, Seoul National University, Seoul 08826, Korea
- Inter-university Semiconductor Research Center, Seoul National University, Seoul 08826, Korea
| | - Changkyun Im
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Korea
- Inter-university Semiconductor Research Center, Seoul National University, Seoul 08826, Korea
- Dental Research Institute, Seoul National University School of Dentistry, Seoul 03080, Korea
| | - Hae-Yong Park
- Department of Physiology, College of Medicine, Hallym University, Chuncheon 24252, Korea
| | - Jong-Mo Seo
- Department of Electrical and Computer Engineering, and Institute of Engineering, Seoul National University, Seoul 08826, Korea
- Inter-university Semiconductor Research Center, Seoul National University, Seoul 08826, Korea
| | - Jun-Min Kim
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Korea.
- Inter-university Semiconductor Research Center, Seoul National University, Seoul 08826, Korea.
- Department of Electronic Communication Engineering, Gyeonggi University of Science Technology, Siheung 15073, Korea.
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Im C, Seo H, Jun S. The effect of number of electrodes in the multi-array tDCS - A computational study. Brain Stimul 2019. [DOI: 10.1016/j.brs.2018.12.437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Choi G, Lee J, Kim H, Jang J, Im C, Jeon N, Jung W. Image-guided recording system for spatial and temporal mapping of neuronal activities in brain slice. J Biophotonics 2018; 11:e201700243. [PMID: 29215208 DOI: 10.1002/jbio.201700243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/10/2017] [Indexed: 06/07/2023]
Abstract
In this study, we introduce the novel image-guided recording system (IGRS) for efficient interpretation of neuronal activities in the brain slice. IGRS is designed to combine microelectrode array (MEA) and optical coherence tomography at the customized upright microscope. It allows to record multi-site neuronal signals and image of the volumetric brain anatomy in a single body configuration. For convenient interconnection between a brain image and neuronal signals, we developed the automatic mapping protocol that enables us to project acquired neuronal signals on a brain image. To evaluate the performance of IGRS, hippocampal signals of the brain slice were monitored, and corresponding with two-dimensional neuronal maps were successfully reconstructed. Our results indicated that IGRS and mapping protocol can provide the intuitive information regarding long-term and multi-sites neuronal signals. In particular, the temporal and spatial mapping capability of neuronal signals would be a very promising tool to observe and analyze the massive neuronal activity and connectivity in MEA-based electrophysiological studies.
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Affiliation(s)
- Geonho Choi
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jeonghyeon Lee
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Hyeongeun Kim
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jaemyung Jang
- Department of Neural Development and Disease, Korea Brain Research Institute, Daegu, Republic of Korea
| | - Changkyun Im
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Republic of Korea
| | - Nooli Jeon
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Republic of Korea
| | - Woonggyu Jung
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
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Seo IS, Lee HG, Koo B, Koh CS, Park HY, Im C, Shin HC. Cross detection for odor of metabolic waste between breast and colorectal cancer using canine olfaction. PLoS One 2018; 13:e0192629. [PMID: 29438432 PMCID: PMC5811037 DOI: 10.1371/journal.pone.0192629] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 01/26/2018] [Indexed: 02/01/2023] Open
Abstract
Although several studies have been performed to detect cancer using canine olfaction, none have investigated whether canine olfaction trained to the specific odor of one cancer is able to detect odor related to other unfamiliar cancers. To resolve this issue, we employed breast and colorectal cancer in vitro, and investigated whether trained dogs to odor related to metabolic waste from breast cancer are able to detect it from colorectal cancer, and vice versa. The culture liquid samples used in the cultivation of cancerous cells (4T1 and CT26) were employed as an experimental group. Two different breeds of dogs were trained for the different cancer odor each other. The dogs were then tested using a double-blind method and cross-test to determine whether they could correctly detect the experimental group, which contains the specific odor for metabolic waste of familiar or unfamiliar cancer. For two cancers, both dogs regardless of whether training or non-training showed that accuracy was over 90%, and sensitivity and specificity were over 0.9, respectively. Through these results, it was verified that the superior olfactory ability of dogs can discriminate odor for metabolic waste of cancer cells from it of benign cells, and that the specific odor for metabolic waste of breast cancer has not significant differences to it of colorectal cancer. That is, it testifies that metabolic waste between breast and colorectal cancer have the common specific odor in vitro. Accordingly, a trained dogs for detecting odor for metabolic waste of breast cancer can perceive it of colorectal cancer, and vice versa. In order to the future work, we will plan in vivo experiment for the two cancers and suggest research as to what kind of cancers have the common specific odor. Furthermore, the relationship between breast and colorectal cancer should be investigated using other research methods.
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Affiliation(s)
- In-Seok Seo
- College of Medicine, Hallym University, Chuncheon, Korea
- Gangwon Provincial Police Agency, Chuncheon, Korea
| | - Hwan-Gon Lee
- Department of Physical Education, Hallym University, Chuncheon, Korea
| | - Bonkon Koo
- School of Interdisciplinary Bioscience and Bioengineering, POSTECH, Pohang, Korea
| | - Chin Su Koh
- College of Medicine, Hallym University, Chuncheon, Korea
| | - Hae-Yong Park
- College of Medicine, Hallym University, Chuncheon, Korea
| | - Changkyun Im
- College of Medicine, Hallym University, Chuncheon, Korea
| | - Hyung-Cheul Shin
- College of Medicine, Hallym University, Chuncheon, Korea
- * E-mail:
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Choi C, Choi MK, Liu S, Kim MS, Park OK, Im C, Kim J, Qin X, Lee GJ, Cho KW, Kim M, Joh E, Lee J, Son D, Kwon SH, Jeon NL, Song YM, Lu N, Kim DH. Human eye-inspired soft optoelectronic device using high-density MoS 2-graphene curved image sensor array. Nat Commun 2017; 8:1664. [PMID: 29162854 PMCID: PMC5698290 DOI: 10.1038/s41467-017-01824-6] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 10/18/2017] [Indexed: 12/17/2022] Open
Abstract
Soft bioelectronic devices provide new opportunities for next-generation implantable devices owing to their soft mechanical nature that leads to minimal tissue damages and immune responses. However, a soft form of the implantable optoelectronic device for optical sensing and retinal stimulation has not been developed yet because of the bulkiness and rigidity of conventional imaging modules and their composing materials. Here, we describe a high-density and hemispherically curved image sensor array that leverages the atomically thin MoS2-graphene heterostructure and strain-releasing device designs. The hemispherically curved image sensor array exhibits infrared blindness and successfully acquires pixelated optical signals. We corroborate the validity of the proposed soft materials and ultrathin device designs through theoretical modeling and finite element analysis. Then, we propose the ultrathin hemispherically curved image sensor array as a promising imaging element in the soft retinal implant. The CurvIS array is applied as a human eye-inspired soft implantable optoelectronic device that can detect optical signals and apply programmed electrical stimulation to optic nerves with minimum mechanical side effects to the retina. Soft and flexible optoelectronic devices may provide effective routes toward retinal implants for enhanced visual functions. Here, the authors fabricate a curved array of flexible MoS2-graphene photodetectors and demonstrate its potential application as ophthalmic imaging element in mouse models.
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Affiliation(s)
- Changsoon Choi
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Moon Kee Choi
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Siyi Liu
- Center for Mechanics of Solids, Structures, and Materials, Department of Aerospace Engineering and Engineering Mechanics, University of Texas at Austin, 210 E 24th St, Austin, TX, 78712, USA
| | - Min Sung Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ok Kyu Park
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
| | - Changkyun Im
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jaemin Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Xiaoliang Qin
- Onfea Computing LLC, 204 Jackson Street, Newton, MA, 02459, USA
| | - Gil Ju Lee
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Kyoung Won Cho
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Myungbin Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Eehyung Joh
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jongha Lee
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Donghee Son
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea
| | - Seung-Hae Kwon
- Division of Bio-imaging, Korea Basic Science Institute, Chun-Cheon, 24341, Republic of Korea
| | - Noo Li Jeon
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Young Min Song
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Nanshu Lu
- Center for Mechanics of Solids, Structures, and Materials, Department of Aerospace Engineering and Engineering Mechanics, University of Texas at Austin, 210 E 24th St, Austin, TX, 78712, USA. .,Department of Electrical and Computer Engineering, Department of Biomedical Engineering, Texas Materials Institute, the University of Texas at Austin, Austin, TX, 78712, USA.
| | - Dae-Hyeong Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea. .,School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, 08826, Republic of Korea.
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Im C, Koh CS, Park HY, Shin J, Jun S, Jung HH, Ahn JM, Chang JW, Kim YJ, Shin HC. Development of wireless neural interface system. Biomed Eng Lett 2017. [DOI: 10.1007/s13534-016-0232-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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11
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Bang S, Lee SR, Ko J, Son K, Tahk D, Ahn J, Im C, Jeon NL. A Low Permeability Microfluidic Blood-Brain Barrier Platform with Direct Contact between Perfusable Vascular Network and Astrocytes. Sci Rep 2017; 7:8083. [PMID: 28808270 PMCID: PMC5556097 DOI: 10.1038/s41598-017-07416-0] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 06/26/2017] [Indexed: 12/14/2022] Open
Abstract
A novel three dimensional blood brain barrier (BBB) platform was developed by independently supplying different types of media to separate cell types within a single device. One channel (vascular channel, VC) is connected to the inner lumen of the vascular network while the other supplies media to the neural cells (neural channel, NC). Compared to co-cultures supplied with only one type of medium (or 1:1 mixture), best barrier properties and viability were obtained with culturing HUVECs with endothelial growth medium (EGM) and neural cells with neurobasal medium supplemented with fetal bovine serum (NBMFBS) independently. The measured vascular network permeability were comparable to reported in vivo values (20 kDa FITC-dextran, 0.45 ± 0.11 × 10−6 cm/s; 70 kDa FITC-dextran, 0.36 ± 0.05 × 10−6 cm/s) and a higher degree of neurovascular interfacing (astrocytic contact with the vascular network, GFAP-CD31 stain overlap) and presence of synapses (stained with synaptophysin). The BBB platform can dependably imitate the perivascular network morphology and synaptic structures characteristic of the NVU. This microfluidic BBB model can find applications in screening pharmaceuticals that target the brain for in neurodegenerative diseases.
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Affiliation(s)
- Seokyoung Bang
- Division of WCU (World Class University) Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, South Korea
| | - Seung-Ryeol Lee
- Division of WCU (World Class University) Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, South Korea
| | - Jihoon Ko
- Division of WCU (World Class University) Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, South Korea
| | - Kyungmin Son
- Division of WCU (World Class University) Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, South Korea
| | - Dongha Tahk
- Division of WCU (World Class University) Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, South Korea
| | - Jungho Ahn
- Division of WCU (World Class University) Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, South Korea
| | - Changkyun Im
- BK21 Plus Transformative Training Program for Creative Mechanical Engineers, Seoul National University, Seoul, South Korea
| | - Noo Li Jeon
- Division of WCU (World Class University) Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, South Korea. .,Institute of Advanced Machinery and Design, Seoul National University, Seoul, South Korea.
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Im C, Park HY, Koh CS, Ryu SB, Seo IS, Kim YJ, Kim KH, Shin HC. Decoding intravesical pressure from local field potentials in rat lumbosacral spinal cord. J Neural Eng 2016; 13:056005. [DOI: 10.1088/1741-2560/13/5/056005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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13
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Eom K, Im C, Hwang S, Eom S, Kim TS, Jeong HS, Kim KH, Byun KM, Jun SB, Kim SJ. Synergistic combination of near-infrared irradiation and targeted gold nanoheaters for enhanced photothermal neural stimulation. Biomed Opt Express 2016; 7:1614-25. [PMID: 27446678 PMCID: PMC4929664 DOI: 10.1364/boe.7.001614] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/20/2016] [Accepted: 03/29/2016] [Indexed: 05/19/2023]
Abstract
Despite a potential of infrared neural stimulation (INS) for modulating neural activities, INS suffers from limited light confinement and bulk tissue heating. Here, a novel methodology for an advanced optical stimulation is proposed by combining near-infrared (NIR) stimulation with gold nanorods (GNRs) targeted to neuronal cell membrane. We confirmed experimentally that in vitro and in vivo neural activation is associated with a local heat generation based on NIR stimulation and GNRs. Compared with the case of NIR stimulation without an aid of GNRs, combination with cell-targeted GNRs allows photothermal stimulation with faster neural response, lower delivered energy, higher stimulation efficiency and stronger behavior change. Since the suggested method can reduce a requisite radiant exposure level and alleviate a concern of tissue damage, it is expected to open up new possibilities for applications to optical neuromodulations for diverse excitable tissues and treatments of neurological disorders.
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Affiliation(s)
- Kyungsik Eom
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 151-744, South Korea
| | - Changkyun Im
- Department of Biomedical Engineering, Yonsei University, Wonju 220-710, South Korea
| | - Seoyoung Hwang
- Department of Electronics Engineering, Ewha Womans University, Seoul 120-750, South Korea
| | - Seyoung Eom
- Department of Biomedical Engineering, Kyung Hee University, Yongin 446-701, South Korea
| | - Tae-Seong Kim
- Department of Biomedical Engineering, Kyung Hee University, Yongin 446-701, South Korea
| | - Hae Sun Jeong
- Department of Electronics Engineering, Ewha Womans University, Seoul 120-750, South Korea
| | - Kyung Hwan Kim
- Department of Biomedical Engineering, Yonsei University, Wonju 220-710, South Korea
| | - Kyung Min Byun
- Department of Biomedical Engineering, Kyung Hee University, Yongin 446-701, South Korea;
| | - Sang Beom Jun
- Department of Electronics Engineering, Ewha Womans University, Seoul 120-750, South Korea; Department of Brain and Cognitive Sciences, Ewha Womans University, Seoul 120-750, South Korea;
| | - Sung June Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 151-744, South Korea;
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Im C, Jung K, Yoon MO, Kim S. PP255-MON: Pilot Study of Safety and Anxiety for Preoperative Oral Carbohydrate-Rich Solution Administration in Pediatric Surgery Patients. Clin Nutr 2014. [DOI: 10.1016/s0261-5614(14)50589-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Park JH, Kim CE, Shin J, Im C, Koh CS, Seo IS, Kim SJ, Shin HC. Detecting bladder fullness through the ensemble activity patterns of the spinal cord unit population in a somatovisceral convergence environment. J Neural Eng 2013; 10:056009. [DOI: 10.1088/1741-2560/10/5/056009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Ryu SB, Bae EK, Kim J, Hwang YS, Im C, Chang JW, Shin HC, Kim KH. Neuronal Responses in the Globus Pallidus during Subthalamic Nucleus Electrical Stimulation in Normal and Parkinson's Disease Model Rats. Korean J Physiol Pharmacol 2013; 17:299-306. [PMID: 23946689 PMCID: PMC3741486 DOI: 10.4196/kjpp.2013.17.4.299] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 05/16/2013] [Accepted: 06/05/2013] [Indexed: 11/15/2022]
Abstract
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has been widely used as a treatment for the movement disturbances caused by Parkinson's disease (PD). Despite successful application of DBS, its mechanism of therapeutic effect is not clearly understood. Because PD results from the degeneration of dopamine neurons that affect the basal ganglia (BG) network, investigation of neuronal responses of BG neurons during STN DBS can provide informative insights for the understanding of the mechanism of therapeutic effect. However, it is difficult to observe neuronal activity during DBS because of large stimulation artifacts. Here, we report the observation of neuronal activities of the globus pallidus (GP) in normal and PD model rats during electrical stimulation of the STN. A custom artifact removal technique was devised to enable monitoring of neural activity during stimulation. We investigated how GP neurons responded to STN stimulation at various stimulation frequencies (10, 50, 90 and 130 Hz). It was observed that activities of GP neurons were modulated by stimulation frequency of the STN and significantly inhibited by high frequency stimulation above 50 Hz. These findings suggest that GP neuronal activity is effectively modulated by STN stimulation and strongly dependent on the frequency of stimulation.
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Affiliation(s)
- Sang Baek Ryu
- Department of Biomedical Engineering, College of Health Science, Yonsei University, Wonju 220-710, Korea
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Abstract
We proposed a method of making a flexible depth-type neural probe using liquid crystal polymer. Conventional depth neural probes made of metal or silicon have the limitations of a single recording site per shank or the brittleness of the silicon substrate. To avoid these drawbacks, polymer-based depth neural probes have been developed with biocompatible polymers such as polyimides or parylenes. However, those have suffered from the difficulty of inserting the probes into brain tissues due to their high flexibility, requiring mechanical reinforcements. Herein, we report the first attempt to use a flexible material, liquid crystal polymer (LCP), as a substrate for a depth-type neural probe. The LCP-based probe offers a controllable stiffness vs. flexibility and compatibility with thin-film processes in addition to its inherent characteristics such as high reliability and biocompatibility. In the present study, an LCP neural probe was fabricated to have enough stiffness to penetrate the dura mater of rodent brains without a guide tool or additional reinforcement structures. A simultaneous multichannel neural recording was successfully achieved from the somatosensory motor cortex of the rodents. Immunohistochemistry showed that the electrodes could be inserted into the desired regions in the brain.
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Affiliation(s)
- Sung Eun Lee
- Department of Electrical Engineering and Computer Science, Inter-University Semiconductor Research Center, Seoul National University, Seoul, 151-744, Korea.
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Lee HJ, Nam Y, Koh CS, Im C, Seo IS, Choi S, Shin HC. Odor-Dependent Hemodynamic Responses Measured with NIRS in the Main Olfactory Bulb of Anesthetized Rats. Exp Neurobiol 2012; 20:189-96. [PMID: 22355264 PMCID: PMC3268153 DOI: 10.5607/en.2011.20.4.189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 03/02/2011] [Indexed: 11/19/2022] Open
Abstract
In this study, we characterize the hemodynamic changes in the main olfactory bulb of anesthetized Sprague-Dawley (SD) rats with near-infrared spectroscopy (NIRS, ISS Imagent) during presentation of two different odorants. Odorants were presented for 10 seconds with clean air via an automatic odor stimulator. Odorants are: (i) plain air as a reference (Blank), (ii) 2-Heptanone (HEP), (iii) Isopropylbenzene (IB). Our results indicated that a plain air did not cause any change in the concentrations of oxygenated (Δ[HbO(2)]) and deoxygenated hemoglobin (Δ[Hbr]), but HEP and IB induced strong changes. Furthermore, these odor-specific changes had regional differences within the MOB. Our results suggest that NIRS technology might be a useful tool to identify of various odorants in a non-invasive manner using animals which has a superb olfactory system.
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Affiliation(s)
- Hyun Joo Lee
- Department of Physiology, College of Medicine, Hallym University, Chuncheon 200-702, Korea
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Abstract
AbstractPhase transition behavior of silicone based liquid crystalline (LC) polymers with variable isotropic transition temperatures (Ti), synthesized from poly(methyl hydrosiloxane), 10-undecenoic acid based crosslinking agent and cholesterol based side chain mesogen, was studied by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and X-ray diffraction (XRD) measurements. The chemical structure of the mesogenic monomer and the LC polymers were confirmed by Fourier transform infra-red (FT-IR) spectroscopy and 1HNMR spectroscopy. DSC studies showed that the glass transition temperatures (Tg) and Ti of the LC polymers decreased with increasing proportion of mesogenic crosslinking agent at its low proportion and at its higher proportion Ti disappeared completely indicating that the polymeric chains had less chance to orient in the network structure. The results were consistent with the XRD and POM studies.
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Affiliation(s)
- R. N. Jana
- 1Department of Chemistry, Institute of Ubiquitous Information Technology and Applications (UbITA), Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul- 143701, South Korea
| | - H. Bhunia
- 2Department of Chemical Engineering, Thapar University, Patiala-147004, India
| | - C. Im
- 1Department of Chemistry, Institute of Ubiquitous Information Technology and Applications (UbITA), Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul- 143701, South Korea
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You KJ, Ham HG, Lee HJ, Lang Y, Im C, Koh CS, Kim MY, Shin HC, Shin HC. Odor discrimination using neural decoding of the main olfactory bulb in rats. IEEE Trans Biomed Eng 2010; 58:1208-15. [PMID: 21193366 DOI: 10.1109/tbme.2010.2103312] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This paper presents a novel method for inferring the odor based on neural activities observed from rats' main olfactory bulbs. Multichannel extracellular single unit recordings were done by microwire electrodes (tungsten, 50 μm, 32 channels) implanted in the mitral/tufted cell layers of the main olfactory bulb of anesthetized rats to obtain neural responses to various odors. Neural response as a key feature was measured by subtraction of neural firing rate before stimulus from after. For odor inference, we have developed a decoding method based on the maximum likelihood estimation. The results have shown that the average decoding accuracy is about 100.0%, 96.0%, 84.0%, and 100.0% with four rats, respectively.
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Affiliation(s)
- Kyung-Jin You
- Department of Electronic Engineering, College of IT, Soongsil University, Seoul 156-743, Korea.
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Ryu S, Kim S, Hwang E, Im C, Oh K, Jung S, Kang T, Kwon D, Park K. UP-1.26: The role of alpha 1(A) Adrenoceptor antagonist tamsulosin for the treatment of patients with lower urinary tract symptoms in women: the effect of nocturia and sleep quality. Urology 2010. [DOI: 10.1016/j.urology.2010.07.159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Jana RN, Kumar A, Im C. Molecular Orientation of Polyurethane Based Liquid Crystal Polymers by Corona Poling. J of Macromolecular Sc , Part A 2009. [DOI: 10.1080/10601320903158719] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Jana RN, Im C. Isothermal Crystallization Behavior of Poly(ε-Caprolactone) Diol/Functionalized-Multiwalled Carbon Nanotube Composites. International Journal of Polymer Analysis and Characterization 2009. [DOI: 10.1080/10236660903031074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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24
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Im C, Yim CB, Micetich RG, Daneshtalab M. (1)H-NMR and NOE studies of 2-cephems and 3-cephems. Arch Pharm Res 2008; 20:652-5. [PMID: 18982275 DOI: 10.1007/bf02975227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/1997] [Indexed: 11/25/2022]
Abstract
The(1)H-NMR signals of 2-cephems and 3-cephems have been assigned and the Nuclear Overhauser Effect (NOE) study of these compounds was undertaken.
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Affiliation(s)
- C Im
- College of Pharmacy, Chung-ang University, Heuksuk-Dong, Dongjak-Ku, 156-756, Seoul, Korea
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Chang H, Rha S, Jeung H, Im C, Ahn J, Kwon W, Yoo N, Roh J, Chung H. Association of MDR-1 gene polymorphism 2677G/T(A) and 3435C/T with clinical outcomes of paclitaxel monotherapy in metastatic breast cancer patients. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.14654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Cheon S, Rha S, Jeung H, Im C, Kim S, Kim H, Ahn J, Roh J, Noh S, Chung H. Survival benefit of combined curative resection of the stomach (D2 resection) and liver in gastric cancer patients with liver metastases. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.4580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Hong S, Shin S, Im C, Jeung H, Rha S, Chung H, Roh J, Lee S, Ryoo H, Ahn J. Adjuvant 5-fluorouracil and leucovorin with or without OK-432 in colorectal cancer: A single-institutional study of long-term follow-up. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.15128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Im C, Jung H, Rha S, Ahn J, Shin S, Noh S, Roh J, Chung H. Comparison of taxane-based (docetaxel or paclitaxel) regimens combined with 5-fluorouracil continuous infusion and low dose leucovorin for advanced gastric carcinoma: Analysis of two phase II trials. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.15679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Jeung H, Im C, Rha S, Ahn J, Shin S, Noh S, Roh J, Chung H. A randomized phase II trial of docetaxel plus S-1 versus docetaxel plus cisplatin in advanced gastric cancer as a first-line treatment. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.4534] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Jeong S, Cho B, Jung J, Im C, Kim Y, Choi H, Park M, Kim S, Chung K, Kim J. Clinical outcomes of adjuvant treatments for invasive thymoma: Dose chemotherapy influence prognosis? J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.7715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7715 Background: The aim of this study was to evaluate therapeutic outcomes and to validate prognostic factors, including adjuvant chemotherapy, in resected thymoma patients who received adjuvant treatment. Methods: One hundred thymoma patients who received post-surgical adjuvant therapy from 1995 to 2005 were retrospectively reviewed. 55 patients received only radiotherapy for the adjuvant therapy, while 45 patients received both radiotherapy and chemotherapy. The total radiation dose was 45–63 Gy, with a median dose of 50.4 Gy. The chemotherapy consisted of 6 cycles of doxorubicin, cisplatin, vincristine, and cyclophosphamide. Treatments were applied every 3–4 weeks. The median follow-up duration was 65 months (range, 5–200 months). Results: The 5-year overall survival (OS) and disease- free survival (DFS) rates were 75.7% (89.2% in stage II, 67.9% in stage III, and 52.1% in stage IVA) and 70.3% (83% in stage II, 62.4% in stage III, and 33.6% in stage IVA) respectively. According to multivariate analysis, the prognostic factors for OS were age, WHO histology, Masaoka stage, and recurrence, while pleural involvement and WHO histology had statistically significant impacts on DFS. Higher radiation dosage, positive resection margins, and adjuvant chemotherapy did not influence survival outcomes. The most common relapse site was the pleura (15 patients, 53.6%). The toxicity from chemotherapy and radiotherapy was manageable, with no deaths due to toxicity. Conclusion: The prognosis of invasive thymoma was poor despite adjuvant treatments with radiotherapy and chemotherapy. In addition to WHO histology, pleural involvement was the most important prognostic factor for recurrence. The pleura was the most common relapse site. Therefore, new modalities to reduce pleural recurrence are warranted. No significant financial relationships to disclose.
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Affiliation(s)
- S. Jeong
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - B. Cho
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - J. Jung
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - C. Im
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Y. Kim
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - H. Choi
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - M. Park
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - S. Kim
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - K. Chung
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
| | - J. Kim
- Yonsei Cancer Center, Seoul, Republic of Korea; NHIC Ilsan Hospital, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea
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Cho B, Im C, Choi H, Shin S, Sohn J, Kim J, Kim S, Moon J, Kim Y. A phase II study of erlotinib treatment in advanced non-small cell lung cancer after failure of gefitinib: Is a clinical benefit still achievable? J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.7609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7609 Background: To evaluate the efficacy and toxicity of erlotinib in patients (pts) with advanced NSCLC who had progression after treatment with gefitinib. Methods: The study included stage IIIB/IV recurrent or metastatic NSCLC pts who have received 2 or 3 prior chemotherapy regimens and showed documented disease progression during or within 4 months after treatment with gefitinib. Pts received erlotinib 150 mg daily until disease progression or unacceptable toxicity. We analyzed EGFR mutations and other genetic abnormality from available tumor samples. Results: Pts and disease characteristics (n = 21) included median age 56 years; number of prior chemotherapy regimens (two, n=10; three, n=11); male (n=10); adenocarcinoma (n=15); and smoking status (never, n=11; former, n=3; current, n=7). Among the 17 pts with tumor samples available, EGFR mutation were detected in 5 (29.4 %). The DCR and RR for all pts were 28.6% (95% CI, 16.7 to 59.6%) and 9.5% (95% CI, 5.6 to 19.8%). All responders were EGFR nonmutants, with long duration of disease control on prior gefitinib therapy (>180 days). The median duration of disease control was 125 days (95% CI, 73–261 days). The median progression-free survival and overall survival were 60 days (95% CI, 43–77 days) and 158 days (95% CI, 141–175 days), respectively. Pts who had SD on gefitinib showed significantly higher DCR (75% vs. 17.6% in non-SD pts, P= 0.050) and RR (50.0% vs. 0% in non-SD pts, P= 0.029). These pts also showed longer median PFS (140 vs. 37 days in non-SD pts, P= 0.005) and OS (not reached vs. 120 days in non-SD pts, P= 0.043). Among 17 pts with biomarker results available, EGFR nonmutants who had SD on gefitinib showed significantly higher DCR (100% vs. 21.4% in non-SD and/or EGFR mutants, P= 0.029) and RR (RR, 66.7 % vs. 0 % in non-SD and/or EGFR mutants, P= 0.022). Conclusions: Erlotinib seems to be a potential therapeutic option for the treatment of selected pts with gefitinib-nonresponsive, EGFR nonmutant, advanced NSCLC. No significant financial relationships to disclose. [Table: see text]
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Affiliation(s)
- B. Cho
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - C. Im
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - H. Choi
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - S. Shin
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - J. Sohn
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - J. Kim
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - S. Kim
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - J. Moon
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
| | - Y. Kim
- Yonsei Cancer Center, Seoul, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; National Health Insurance Ilsan Hospital, Koyang, Republic of Korea
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Im C, Lupton JM, Schouwink P, Heun S, Becker H, Baessler H. Erratum: “Fluorescence dynamics of phenylene substituted polyphenylenevinylene–trinitrofluorenone blend systems” [J. Chem. Phys. 117, 1395 (2002)]. J Chem Phys 2003. [DOI: 10.1063/1.1522371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Im C, Emelianova EV, Bässler H, Spreitzer H, Becker H. Intrinsic and extrinsic charge carrier photogeneration in phenyl-substituted polyphenylenevinylene-trinitrofluorenone blend systems. J Chem Phys 2002. [DOI: 10.1063/1.1490581] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Im C, Lupton JM, Schouwink P, Heun S, Becker H, Bässler H. Fluorescence dynamics of phenyl-substituted polyphenylenevinylene–trinitrofluorenone blend systems. J Chem Phys 2002. [DOI: 10.1063/1.1484102] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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36
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Im C, Bässler H, Rost H, Hörhold HH. Hole transport in polyphenylenevinylene-ether under bulk photoexcitation and sensitized injection. J Chem Phys 2000. [DOI: 10.1063/1.1287657] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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37
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West D, Rahn M, Im C, Bässler H. Hole transport through chromophores in a photorefractive polymer composite based on poly(N-vinylcarbazole). Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(00)00849-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
The 6,6-dibromopenam (6) was treated with CH3MgBr and carbaldehyde 5 to afford the hydroxy compound 7, which was reacted with acetic anhydride to give acetoxy compound 8. The deacetobromination of 8 with zinc and acetic acid gave 6-exomethylenepenams, E-isomer 10 and Z-isomer 9, which was oxidized to sulfone 11 by m-CPBA. The p-methoxybenzyl compounds were deprotected by AlCl3 and neutralized to give the sodium salts 12, 13 and 14.
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Affiliation(s)
- C Im
- College of Pharmacy, Chung-Ang University, Seoul, Korea
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Koo S, Kwon K, Im C, Lee Y, Park JW. Detection of a dup(17q) and inv(16) by fluorescence in situ hybridization in acute myelomonocytic leukemia. Cancer Genet Cytogenet 1997; 98:87-9. [PMID: 9309125 DOI: 10.1016/s0165-4608(96)00394-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Two cases of acute myelomonocytic leukemia (AMMoL) of FAB type M4Eo are described in which a primary subclone containing a dup(17)(q21q25) and a subclone containing dup(17)(q21q25), inv(16)(p13q22) were seen in one patient, and -7, dup(17)(q21q25) in another. Fluorescence in situ hybridization (FISH) was carried out for the confirmation of the duplicated segment and breakpoint of inv(16). Inv(16) is a well known anomaly in AMMoL, whereas dup(17q) is rare though as not yet confirmed, this anomaly could be a nonrandom or novel change in AMMoL.
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Affiliation(s)
- S Koo
- Department of Clinical Pathology, Chungnam National University Hospital, DaeJon, Korea
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Im C, Maiti SN, Micetich RG, Daneshtalab M, Atchison K, Phillips OA, Kunugita C. Synthesis and beta-lactamase inhibitory activity of 6-[(1-heteroarylthioethyl-1,2,3-triazol-4-yl)-methylene]penam sulfones. J Antibiot (Tokyo) 1994; 47:1030-40. [PMID: 7928691 DOI: 10.7164/antibiotics.47.1030] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The synthesis of beta-lactamase inhibitory activity of a series of sodium 6-[(1-heteroarylthioethyl-1,2,3-triazol-4-yl)methylene]pe nicillanate, 1,1-dioxides are described. Their activity was compared with tazobactam and sulbactam. The Z-isomers were more active than the E-isomers. The in vitro activity of the Z-isomers of the phenylthiadiazole derivatives (13a and 15a) was better than sulbactam against the tested beta-lactamases and comparable to tazobactam especially against TEM-2 and cephalosporinase. But their synergistic activity with five antibiotics was inferior to tazobactam.
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Affiliation(s)
- C Im
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada
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Im C, Knaus EE, Thuynsma RP, Allen TM. Synthesis and cytotoxic activity of (E)-1-(2-nitrovinyl) and 1-[N-(tert-butylformiminyl)]-substituted 1,4-dihydropyridines and 2-pyridones. Drug Des Deliv 1990; 5:239-48. [PMID: 1670504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1-(2-Nitrovinyl) derivatives of nuclear substituted 1,4-dihydropyridines (7a-c), and 1-(N-tert-butyl-formiminyl) derivatives of 1,4-dihydropyridines (9a-c) or 2-pyridones (11a-c) were synthesized for evaluation as cytotoxic agents (see Table I for structures). The in vitro cytotoxic activities, determined in the L1210 assay, indicated that the 4-substituent on a 1,4-dihydropyridine ring system was a determinant of activity in both the 1-(2-nitrovinyl) (7) and 1-(N-tert-butylformiminyl) (9) series, the relative activity order being n-Bu > Ph > Me. In the 1-(N-tert-butylformiminyl) series, the 1,4-dihydropyridine derivatives (9) were generally more cytotoxic than the 2-pyridone derivatives (11). The most active compound was 1-(N-tert-butylformiminyl)-3-(4,4-dimethyloxazolin-2-yl)-4-n -butyl-1,4- dihydropyridine (9b), but it was 2-3 log units less active than the reference standard melphalan.
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Affiliation(s)
- C Im
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada
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