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Yeom H, Kim N, Lee AC, Kim J, Kim H, Choi H, Song SW, Kwon S, Choi Y. Highly Accurate Sequence- and Position-Independent Error Profiling of DNA Synthesis and Sequencing. ACS Synth Biol 2023; 12:3567-3577. [PMID: 37961855 PMCID: PMC10729760 DOI: 10.1021/acssynbio.3c00308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 11/01/2023] [Accepted: 11/01/2023] [Indexed: 11/15/2023]
Abstract
A comprehensive error analysis of DNA-stored data during processing, such as DNA synthesis and sequencing, is crucial for reliable DNA data storage. Both synthesis and sequencing errors depend on the sequence and the transition of bases of nucleotides; ignoring either one of the error sources leads to technical challenges in minimizing the error rate. Here, we present a methodology and toolkit that utilizes an oligonucleotide library generated from a 10-base-shifted sequence array, which is individually labeled with unique molecular identifiers, to delineate and profile DNA synthesis and sequencing errors simultaneously. This methodology enables position- and sequence-independent error profiling of both DNA synthesis and sequencing. Using this toolkit, we report base transitional errors in both synthesis and sequencing in general DNA data storage as well as degenerate-base-augmented DNA data storage. The methodology and data presented will contribute to the development of DNA sequence designs with minimal error.
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Affiliation(s)
- Huiran Yeom
- Division
of Data Science, College of Information and Communication Technology, The University of Suwon, Hwaseong 18323, Republic of Korea
| | - Namphil Kim
- Department
of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | | | - Jinhyun Kim
- Department
of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Hamin Kim
- Department
of Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
| | - Hansol Choi
- Bio-MAX
Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Seo Woo Song
- Basic Science
and Engineering Initiative, Children’s Heart Center, Stanford University, Stanford, California 94304, United States
| | - Sunghoon Kwon
- Department
of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
- Department
of Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
- Bio-MAX
Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Yeongjae Choi
- School
of Materials Science and Engineering, Gwangju
Institute of Science and Technology (GIST), Gwangju 61105, Republic of Korea
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2
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Kim S, Kim N, Kang HM, Jang HJ, Lee AC, Na KJ. Canine Somatic Mutations from Whole-Exome Sequencing of B-Cell Lymphomas in Six Canine Breeds-A Preliminary Study. Animals (Basel) 2023; 13:2846. [PMID: 37760246 PMCID: PMC10525272 DOI: 10.3390/ani13182846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/05/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Canine lymphoma (CL) is one of the most common malignant tumors in dogs. The cause of CL remains unclear. Genetic mutations that have been suggested as possible causes of CL are not fully understood. Whole-exome sequencing (WES) is a time- and cost-effective method for detecting genetic variants targeting only the protein-coding regions (exons) that are part of the entire genome region. A total of eight patients with B-cell lymphomas were recruited, and WES analysis was performed on whole blood and lymph node aspirate samples from each patient. A total of 17 somatic variants (GOLIM4, ITM2B, STN1, UNC79, PLEKHG4, BRF1, ENSCAFG00845007156, SEMA6B, DSC1, TNFAIP1, MYLK3, WAPL, ADORA2B, LOXHD1, GP6, AZIN1, and NCSTN) with moderate to high impact were identified by WES analysis. Through a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of 17 genes with somatic mutations, a total of 16 pathways were identified. Overall, the somatic mutations identified in this study suggest novel candidate mutations for CL, and further studies are needed to confirm the role of these mutations.
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Affiliation(s)
- Sungryong Kim
- Laboratory of Veterinary Laboratory Medicine, College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea; (S.K.); (H.-M.K.)
| | - Namphil Kim
- Biophotonics and Nano Engineering Laboratory, Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Republic of Korea;
| | - Hyo-Min Kang
- Laboratory of Veterinary Laboratory Medicine, College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea; (S.K.); (H.-M.K.)
| | - Hye-Jin Jang
- Department of Biomedical Laboratory Science, Daegu Health College, Daegu 41453, Republic of Korea;
| | | | - Ki-Jeong Na
- Laboratory of Veterinary Laboratory Medicine, College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea; (S.K.); (H.-M.K.)
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3
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Song SW, Lee S, Choe JK, Lee AC, Shin K, Kang J, Kim G, Yeom H, Choi Y, Kwon S, Kim J. Pen-drawn Marangoni swimmer. Nat Commun 2023; 14:3597. [PMID: 37328461 DOI: 10.1038/s41467-023-39186-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/30/2023] [Indexed: 06/18/2023] Open
Abstract
Pen-drawing is an intuitive, convenient, and creative fabrication method for delivering emergent and adaptive design to real devices. To demonstrate the application of pen-drawing to robot construction, we developed pen-drawn Marangoni swimmers that perform complex programmed tasks using a simple and accessible manufacturing process. By simply drawing on substrates using ink-based Marangoni fuel, the swimmers demonstrate advanced robotic motions such as polygon and star-shaped trajectories, and navigate through maze. The versatility of pen-drawing allows the integration of the swimmers with time-varying substrates, enabling multi-step motion tasks such as cargo delivery and return to the original place. We believe that our pen-based approach will significantly expand the potential applications of miniaturized swimming robots and provide new opportunities for simple robotic implementations.
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Affiliation(s)
- Seo Woo Song
- Bio-MAX Institute, Seoul National University, Seoul, South Korea.
- Basic Science and Engineering Initiative, Children's Heart Center, Stanford University, Stanford, CA, USA.
| | - Sumin Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, South Korea
- Meteor Biotech, Co. Ltd., Seoul, South Korea
| | - Jun Kyu Choe
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea
| | - Amos Chungwon Lee
- Bio-MAX Institute, Seoul National University, Seoul, South Korea
- Meteor Biotech, Co. Ltd., Seoul, South Korea
| | - Kyoungseob Shin
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, South Korea
| | - Junwon Kang
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, South Korea
| | - Gyeongjun Kim
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, South Korea
| | - Huiran Yeom
- Division of Data Science, College of Information and Communication Technology, The University of Suwon, Hwaseong, South Korea
| | - Yeongjae Choi
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Sunghoon Kwon
- Bio-MAX Institute, Seoul National University, Seoul, South Korea.
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, South Korea.
- Inter-University Semiconductor Research Center, Seoul, 08826, South Korea.
| | - Jiyun Kim
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea.
- Center for Multidimensional Programmable Matter, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea.
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4
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Affiliation(s)
- Amos Chungwon Lee
- Bio-MAX Institute, Seoul National University and Meteor Biotech, Co. Ltd, Seoul, Republic of Korea.
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Lee S, Lee W, Lee AC, Nam J, Lee J, Kim H, Jeong Y, Yeom H, Kim N, Song SW, Kwon S. I-LIFT (image-based laser-induced forward transfer) platform for manipulating encoded microparticles. Biomicrofluidics 2022; 16:061101. [PMID: 36483021 PMCID: PMC9726220 DOI: 10.1063/5.0131733] [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] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 11/08/2022] [Indexed: 06/17/2023]
Abstract
Encoded microparticles have great potential in small-volume multiplexed assays. It is important to link the micro-level assays to the macro-level by indexing and manipulating the microparticles to enhance their versatility. There are technologies to actively manipulate the encoded microparticles, but none is capable of directly manipulating the encoded microparticles with homogeneous physical properties. Here, we report the image-based laser-induced forward transfer system for active manipulation of the graphically encoded microparticles. By demonstrating the direct retrieval of the microparticles of interest, we show that this system has the potential to expand the usage of encoded microparticles.
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Affiliation(s)
- Sumin Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Wooseok Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Amos Chungwon Lee
- Bio-MAX Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Juhong Nam
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - JinYoung Lee
- Division of Engineering Science, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Hamin Kim
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Yunjin Jeong
- Bio-MAX Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Huiran Yeom
- Bio-MAX Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Namphil Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Seo Woo Song
- Bio-MAX Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Sunghoon Kwon
- Authors to whom correspondence should be addressed: and
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6
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Park JC, Noh J, Jang S, Kim KH, Choi H, Lee D, Kim J, Chung J, Lee DY, Lee Y, Lee H, Yoo DK, Lee AC, Byun MS, Yi D, Han SH, Kwon S, Mook-Jung I. Association of B cell profile and receptor repertoire with the progression of Alzheimer's disease. Cell Rep 2022; 40:111391. [PMID: 36130492 DOI: 10.1016/j.celrep.2022.111391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 02/28/2022] [Revised: 07/04/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Alzheimer's disease (AD) is the most prevalent type of dementia. Reports have revealed that the peripheral immune system is linked to neuropathology; however, little is known about the contribution of B lymphocytes in AD. For this longitudinal study, 133 participants are included at baseline and second-year follow-up. Also, we analyze B cell receptor (BCR) repertoire data generated from a public dataset of three normal and 10 AD samples and perform BCR repertoire profiling and pairwise sharing analysis. As a result, longitudinal increase in B lymphocytes is associated with increased cerebral amyloid deposition and hyperactivates induced pluripotent stem cell-derived microglia with loss-of-function for beta-amyloid clearance. Patients with AD share similar class-switched BCR sequences with identical isotypes, despite the high somatic hypermutation rate. Thus, BCR repertoire profiling can lead to the development of individualized immune-based therapeutics and treatment. We provide evidence of both quantitative and qualitative changes in B lymphocytes during AD pathogenesis.
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Affiliation(s)
- Jong-Chan Park
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Neuroscience Research Institute, Medical Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; SNU Dementia Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Jinsung Noh
- Department of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea; Bio-MAX Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Sukjin Jang
- Department of Medicine, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Ki Hyun Kim
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Hayoung Choi
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; SNU Dementia Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea
| | - Dongjoon Lee
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; SNU Dementia Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea
| | - Jieun Kim
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea
| | - Junho Chung
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul 03080, Republic of Korea; Department of Biomedical Science, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Dong Young Lee
- Institute of Human Behavioral Medicine, Medical Research Center, Seoul National University, Seoul 03080, Republic of Korea; Department of Psychiatry, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Department of Neuropsychiatry, Seoul National University Hospital, Seoul 03080, Republic of Korea
| | - Yonghee Lee
- Department of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Hyunho Lee
- Department of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Duck Kyun Yoo
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea; Department of Biomedical Science, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Amos Chungwon Lee
- Bio-MAX Institute, Seoul National University, Seoul 08826, Republic of Korea
| | - Min Soo Byun
- Department of Psychiatry, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Department of Neuropsychiatry, Seoul National University Hospital, Seoul 03080, Republic of Korea
| | - Dahyun Yi
- Department of Neuropsychiatry, Seoul National University Hospital, Seoul 03080, Republic of Korea
| | - Sun-Ho Han
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Neuroscience Research Institute, Medical Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; SNU Dementia Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea.
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea; Bio-MAX Institute, Seoul National University, Seoul 08826, Republic of Korea; BK21+ Creative Research Engineer Development for IT, Seoul National University, Seoul 08826, Republic of Korea; Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Republic of Korea; Interdisciplinary Program in Bioengineering, Seoul National University, Seoul 08826, Republic of Korea.
| | - Inhee Mook-Jung
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Neuroscience Research Institute, Medical Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; SNU Dementia Research Center, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea.
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7
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Choi H, Choi Y, Choi J, Lee AC, Yeom H, Hyun J, Ryu T, Kwon S. Purification of multiplex oligonucleotide libraries by synthesis and selection. Nat Biotechnol 2022; 40:47-53. [PMID: 34326548 DOI: 10.1038/s41587-021-00988-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/16/2021] [Indexed: 02/07/2023]
Abstract
Complex oligonucleotide (oligo) libraries are essential materials for diverse applications in synthetic biology, pharmaceutical production, nanotechnology and DNA-based data storage. However, the error rates in synthesizing complex oligo libraries can be substantial, leading to increment in cost and labor for the applications. As most synthesis errors arise from faulty insertions and deletions, we developed a length-based method with single-base resolution for purification of complex libraries containing oligos of identical or different lengths. Our method-purification of multiplex oligonucleotide libraries by synthesis and selection-can be performed either step-by-step manually or using a next-generation sequencer. When applied to a digital data-encoded library containing oligos of identical length, the method increased the purity of full-length oligos from 83% to 97%. We also show that libraries encoding the complementarity-determining region H3 with three different lengths (with an empirically achieved diversity >106) can be simultaneously purified in one pot, increasing the in-frame oligo fraction from 49.6% to 83.5%.
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Affiliation(s)
- Hansol Choi
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea
| | - Yeongjae Choi
- Nano Systems Institute, Seoul National University, Seoul, Republic of Korea.,Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Jaewon Choi
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, Republic of Korea.,Integrated Major in Innovative Medical Science, Seoul National University, Seoul, Republic of Korea
| | - Amos Chungwon Lee
- Bio-MAX Institute, Seoul National University, Seoul, Republic of Korea
| | - Huiran Yeom
- Bio-MAX Institute, Seoul National University, Seoul, Republic of Korea
| | - Jinwoo Hyun
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea
| | - Taehoon Ryu
- ATG Lifetech Inc., Seoul, Republic of Korea.
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea. .,Nano Systems Institute, Seoul National University, Seoul, Republic of Korea. .,Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, Republic of Korea. .,Bio-MAX Institute, Seoul National University, Seoul, Republic of Korea.
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8
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Song SW, Lee S, Choe JK, Kim NH, Kang J, Lee AC, Choi Y, Choi A, Jeong Y, Lee W, Kim JY, Kwon S, Kim J. Direct 2D-to-3D transformation of pen drawings. Sci Adv 2021; 7:7/13/eabf3804. [PMID: 33762344 PMCID: PMC7990349 DOI: 10.1126/sciadv.abf3804] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 02/08/2021] [Indexed: 05/09/2023]
Abstract
Pen drawing is a method that allows simple, inexpensive, and intuitive two-dimensional (2D) fabrication. To integrate such advantages of pen drawing in fabricating 3D objects, we developed a 3D fabrication technology that can directly transform pen-drawn 2D precursors into 3D geometries. 2D-to-3D transformation of pen drawings is facilitated by surface tension-driven capillary peeling and floating of dried ink film when the drawing is dipped into an aqueous monomer solution. Selective control of the floating and anchoring parts of a 2D precursor allowed the 2D drawing to transform into the designed 3D structure. The transformed 3D geometry can then be fixed by structural reinforcement using surface-initiated polymerization. By transforming simple pen-drawn 2D structures into complex 3D structures, our approach enables freestyle rapid prototyping via pen drawing, as well as mass production of 3D objects via roll-to-roll processing.
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Affiliation(s)
- Seo Woo Song
- Bio-MAX Institute, Seoul National University, Seoul 08826, South Korea
| | - Sumin Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Jun Kyu Choe
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
| | - Na-Hyang Kim
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
| | - Junwon Kang
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
| | - Amos Chungwon Lee
- Bio-MAX Institute, Seoul National University, Seoul 08826, South Korea
| | - Yeongjae Choi
- Nano Systems Institute, Seoul National University, Seoul National University, Seoul 08826, South Korea
| | - Ahyoun Choi
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
| | - Yunjin Jeong
- Bio-MAX Institute, Seoul National University, Seoul 08826, South Korea
| | - Wooseok Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Ju-Young Kim
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
| | - Sunghoon Kwon
- Bio-MAX Institute, Seoul National University, Seoul 08826, South Korea.
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
- Nano Systems Institute, Seoul National University, Seoul National University, Seoul 08826, South Korea
| | - Jiyun Kim
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea.
- Center for Multidimensional Programmable Matter, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
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Yeom H, Ryu T, Lee AC, Noh J, Lee H, Choi Y, Kim N, Kwon S. Cell-Free Bacteriophage Genome Synthesis Using Low-Cost Sequence-Verified Array-Synthesized Oligonucleotides. ACS Synth Biol 2020; 9:1376-1384. [PMID: 32383864 DOI: 10.1021/acssynbio.0c00051] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Synthesizing engineered bacteriophages (phages) for human use has potential in various applications ranging from drug screening using a phage display to clinical use using phage therapy. However, the engineering of phages conventionally involves the use of an in vivo system that has low production efficiency because of high virulence against the host and low transformation efficiency. To circumvent these issues, de novo phage genome synthesis using chemically synthesized oligonucleotides (oligos) has increased the potential for engineering phages in a cell-free system. Here, we present a cell-free, low-cost, de novo gene synthesis technology called Sniper assembly for phage genome construction. With massively parallel sequencing of microarray-synthesized oligos, we generated and identified approximately 100 000 clonal DNA clusters in vitro and 5000 error-free ones in a cell-free environment. To demonstrate its practical application, we synthesized the Acinetobacter phage AP205 genome (4268 bp) using 65 sequence-verified DNA clones. Compared to previous reports, Sniper assembly lowered the genome synthesis cost ($0.0137/bp) by producing low-cost sequence-verified DNA.
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Affiliation(s)
- Huiran Yeom
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Taehoon Ryu
- Department of Molecular Genetic Engineering, Celemics, Inc., Seoul, 08506, Republic of Korea
| | - Amos Chungwon Lee
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jinsung Noh
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Hansaem Lee
- Department of Molecular Genetic Engineering, Celemics, Inc., Seoul, 08506, Republic of Korea
| | - Yeongjae Choi
- Nano Systems Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Namphil Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, South Korea
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, 08826, Republic of Korea
- Bio-MAX institute, Seoul National University, Seoul, 08826, Republic of Korea
- Inter-University Semiconductor Research Center, Seoul, 08826, Republic of Korea
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Odorizzi S, Cheung WJ, Sherbino J, Lee AC, Thurgur L, Frank JR. A Signal Through the Noise: Do Professionalism Concerns Impact the Decision Making of Competence Committees? Acad Med 2020; 95:896-901. [PMID: 31577582 DOI: 10.1097/acm.0000000000003005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
PURPOSE To characterize how professionalism concerns influence individual reviewers' decisions about resident progression using simulated competence committee (CC) reviews. METHOD In April 2017, the authors conducted a survey of 25 Royal College of Physicians and Surgeons of Canada emergency medicine residency program directors and senior faculty who were likely to function as members of a CC (or equivalent) at their institution. Participants took a survey with 12 resident portfolios, each containing hypothetical formative and summative assessments. Six portfolios represented residents progressing as expected (PAE) and 6 represented residents not progressing as expected (NPAE). A professionalism variable (PV) was developed for each portfolio. Two counterbalanced surveys were developed in which 6 portfolios contained a PV and 6 portfolios did not (for each PV condition, 3 portfolios represented residents PAE and 3 represented residents NPAE). Participants were asked to make progression decisions based on each portfolio. RESULTS Without PVs, the consistency of participants giving scores of 1 or 2 (i.e., little or no need for educational intervention) to residents PAE and to those NPAE was 92% and 10%, respectively. When a PV was added, the consistency decreased by 34% for residents PAE and increased by 4% for those NPAE (P = .01). CONCLUSIONS When reviewing a simulated resident portfolio, individual reviewer scores for residents PAE were responsive to the addition of professionalism concerns. Considering this, educators using a CC should have a system to report, collect, and document professionalism issues.
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Affiliation(s)
- Scott Odorizzi
- S. Odorizzi is postgraduate year 5 resident physician, Department of Emergency Medicine, University of Ottawa, Ottawa, Ontario, Canada. W.J. Cheung is assistant professor and staff physician, Department of Emergency Medicine, University of Ottawa, Ottawa, Ontario, Canada. J. Sherbino is professor, Division of Emergency Medicine, Department of Medicine, and assistant dean, health professions education research, McMaster University, Hamilton, Ontario, Canada. A.C. Lee is conjoint associate professor, School of Medicine and Public Health, The University of Newcastle Australia, Callaghan, New South Wales, Australia, and psychometrician, Royal Australasian College of Physicians, Sydney, New South Wales, Australia. L. Thurgur is assistant professor and staff physician, Department of Emergency Medicine, and program director, Royal College Emergency Medicine Residency Program, University of Ottawa, Ottawa, Ontario, Canada. J.R. Frank is associate professor and staff physician, Department of Emergency Medicine, University of Ottawa, and director, Specialty Education, Strategy and Standards, Office of Specialty Education, Royal College of Physicians and Surgeons of Canada, Ottawa, Ontario, Canada
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11
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Kim SD, Song SW, Oh DY, Lee AC, Koo JW, Kang T, Kim MC, Lee C, Jeong Y, Jeong HY, Lee D, Cho S, Kwon S, Kim J. Microspinning: Local Surface Mixing via Rotation of Magnetic Microparticles for Efficient Small-Volume Bioassays. Micromachines (Basel) 2020; 11:mi11020175. [PMID: 32046141 PMCID: PMC7074623 DOI: 10.3390/mi11020175] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [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: 12/06/2019] [Revised: 01/29/2020] [Accepted: 02/04/2020] [Indexed: 12/11/2022]
Abstract
The need for high-throughput screening has led to the miniaturization of the reaction volume of the chamber in bioassays. As the reactor gets smaller, surface tension dominates the gravitational or inertial force, and mixing efficiency decreases in small-scale reactions. Because passive mixing by simple diffusion in tens of microliter-scale volumes takes a long time, active mixing is needed. Here, we report an efficient micromixing method using magnetically rotating microparticles with patterned magnetization induced by magnetic nanoparticle chains. Because the microparticles have magnetization patterning due to fabrication with magnetic nanoparticle chains, the microparticles can rotate along the external rotating magnetic field, causing micromixing. We validated the reaction efficiency by comparing this micromixing method with other mixing methods such as simple diffusion and the use of a rocking shaker at various working volumes. This method has the potential to be widely utilized in suspension assay technology as an efficient mixing strategy.
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Affiliation(s)
- Su Deok Kim
- Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul 08826, Korea; (S.D.K.); (S.W.S.); (A.C.L.); (C.L.); (Y.J.); (S.C.)
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea;
| | - Seo Woo Song
- Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul 08826, Korea; (S.D.K.); (S.W.S.); (A.C.L.); (C.L.); (Y.J.); (S.C.)
| | - Dong Yoon Oh
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, Korea;
| | - Amos Chungwon Lee
- Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul 08826, Korea; (S.D.K.); (S.W.S.); (A.C.L.); (C.L.); (Y.J.); (S.C.)
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, Korea;
| | - Jeong Woo Koo
- Department of Material Science and Engineering, Seoul National University, Seoul 08826, Korea;
| | - Taehun Kang
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea;
| | - Min Chang Kim
- School of Environmental Engineering, University of Seoul, Seoul 08826, Korea
| | - Changhee Lee
- Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul 08826, Korea; (S.D.K.); (S.W.S.); (A.C.L.); (C.L.); (Y.J.); (S.C.)
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea;
| | - Yunjin Jeong
- Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul 08826, Korea; (S.D.K.); (S.W.S.); (A.C.L.); (C.L.); (Y.J.); (S.C.)
| | - Hyun Yong Jeong
- BK21+ Creative Research Engineer Development for IT, Seoul National University, Seoul 08826, Korea; (H.Y.J.); (D.L.)
| | - Daewon Lee
- BK21+ Creative Research Engineer Development for IT, Seoul National University, Seoul 08826, Korea; (H.Y.J.); (D.L.)
| | - Seongkyu Cho
- Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul 08826, Korea; (S.D.K.); (S.W.S.); (A.C.L.); (C.L.); (Y.J.); (S.C.)
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea;
| | - Sunghoon Kwon
- Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul 08826, Korea; (S.D.K.); (S.W.S.); (A.C.L.); (C.L.); (Y.J.); (S.C.)
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea;
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, Korea;
- Correspondence: (S.K.); (J.K.); Tel.: +82-2-880-1736 (S.K.); +82-52-217-3052 (J.K.)
| | - Jiyun Kim
- School of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea
- Correspondence: (S.K.); (J.K.); Tel.: +82-2-880-1736 (S.K.); +82-52-217-3052 (J.K.)
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12
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Kim O, Lee D, Chungwon Lee A, Lee Y, Bae HJ, Lee HB, Kim RN, Han W, Kwon S. Whole Genome Sequencing of Single Circulating Tumor Cells Isolated by Applying a Pulsed Laser to Cell-Capturing Microstructures. Small 2019; 15:e1902607. [PMID: 31240868 DOI: 10.1002/smll.201902607] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [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: 05/21/2019] [Indexed: 06/09/2023]
Abstract
Single cell analysis of heterogeneous circulating tumor cells (CTCs), by which the genomic profiles of rare single CTCs are connected to the clinical status of cancer patients, is crucial for understanding cancer metastasis and the clinical impact on patients. However, the heterogeneity in genotypes and phenotypes and rarity of CTCs have limited extensive single CTC genome research, further hindering clinical investigation. Despite recent efforts to build platforms that separate CTCs, the investigation on CTCs is difficult due to the lack of a retrieval process at the single cell level. In this study, laser-induced isolation of microstructures on an optomechanically-transferrable-chip and sequencing (LIMO-seq) is applied for whole genome sequencing of single CTCs. Also, the whole genome sequences and the molecular profiles of the isolated single cells from the whole blood of a breast cancer patient are analyzed.
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Affiliation(s)
- Okju Kim
- Department of Electrical and Computer Engineering Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Daewon Lee
- Interdisciplinary Program in Bioengineering, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, Republic of Korea
- BK21+ Creative Research Engineer Development for IT, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Amos Chungwon Lee
- Interdisciplinary Program in Bioengineering, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Yongju Lee
- Department of Electrical and Computer Engineering Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Hyung Jong Bae
- Nano Systems Institute, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Han-Byoel Lee
- Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Ryong Nam Kim
- Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
- Biomedical Research Institute, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
- Cancer Research Institute, Seoul National University, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Wonshik Han
- Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
- Cancer Research Institute, Seoul National University, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
- Institutes of Entrepreneurial BioConvergence, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, Republic of Korea
- Inter-University Semiconductor Research Center, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
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13
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Lee AC, Lee Y, Lee D, Kwon S. Divide and conquer: A perspective on biochips for single-cell and rare-molecule analysis by next-generation sequencing. APL Bioeng 2019; 3:020901. [PMID: 31431936 PMCID: PMC6697027 DOI: 10.1063/1.5095962] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 03/13/2019] [Accepted: 05/29/2019] [Indexed: 02/06/2023] Open
Abstract
Recent advances in biochip technologies that connect next-generation sequencing (NGS) to real-world problems have facilitated breakthroughs in science and medicine. Because biochip technologies are themselves used in sequencing technologies, the main strengths of biochips lie in their scalability and throughput. Through the advantages of biochips, NGS has facilitated groundbreaking scientific discoveries and technical breakthroughs in medicine. However, all current NGS platforms require nucleic acids to be prepared in a certain range of concentrations, making it difficult to analyze biological systems of interest. In particular, many of the most interesting questions in biology and medicine, including single-cell and rare-molecule analysis, require strategic preparation of biological samples in order to be answered. Answering these questions is important because each cell is different and exists in a complex biological system. Therefore, biochip platforms for single-cell or rare-molecule analyses by NGS, which allow convenient preparation of nucleic acids from biological systems, have been developed. Utilizing the advantages of miniaturizing reaction volumes of biological samples, biochip technologies have been applied to diverse fields, from single-cell analysis to liquid biopsy. From this perspective, here, we first review current state-of-the-art biochip technologies, divided into two broad categories: microfluidic- and micromanipulation-based methods. Then, we provide insights into how future biochip systems will aid some of the most important biological and medical applications that require NGS. Based on current and future biochip technologies, we envision that NGS will come ever closer to solving more real-world scientific and medical problems.
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Affiliation(s)
- A C Lee
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul 08826, South Korea
| | - Y Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
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14
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Groom KM, McCowan LM, Mackay LK, Lee AC, Gardener G, Unterscheider J, Sekar R, Dickinson JE, Muller P, Reid RA, Watson D, Welsh A, Marlow J, Walker SP, Hyett J, Morris J, Stone PR, Baker PN. STRIDER NZAus: a multicentre randomised controlled trial of sildenafil therapy in early-onset fetal growth restriction. BJOG 2019; 126:997-1006. [PMID: 30779295 DOI: 10.1111/1471-0528.15658] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/31/2019] [Indexed: 12/20/2022]
Abstract
OBJECTIVE To assess the effect of maternal sildenafil therapy on fetal growth in pregnancies with early-onset fetal growth restriction. DESIGN A randomised placebo-controlled trial. SETTING Thirteen maternal-fetal medicine units across New Zealand and Australia. POPULATION Women with singleton pregnancies affected by fetal growth restriction at 22+0 to 29+6 weeks. METHODS Women were randomised to oral administration of 25 mg sildenafil citrate or visually matching placebo three times daily until 32+0 weeks, birth or fetal death (whichever occurred first). MAIN OUTCOME MEASURES The primary outcome was the proportion of pregnancies with an increase in fetal growth velocity. Secondary outcomes included live birth, survival to hospital discharge free of major neonatal morbidity and pre-eclampsia. RESULTS Sildenafil did not affect the proportion of pregnancies with an increase in fetal growth velocity; 32/61 (52.5%) sildenafil-treated, 39/57 (68.4%) placebo-treated [adjusted odds ratio (OR) 0.49, 95% CI 0.23-1.05] and had no effect on abdominal circumference Z-scores (P = 0.61). Sildenafil use was associated with a lower mean uterine artery pulsatility index after 48 hours of treatment (1.56 versus 1.81; P = 0.02). The live birth rate was 56/63 (88.9%) for sildenafil-treated and 47/59 (79.7%) for placebo-treated (adjusted OR 2.50, 95% CI 0.80-7.79); survival to hospital discharge free of major neonatal morbidity was 42/63 (66.7%) for sildenafil-treated and 33/59 (55.9%) for placebo-treated (adjusted OR 1.93, 95% CI 0.84-4.45); and new-onset pre-eclampsia was 9/51 (17.7%) for sildenafil-treated and 14/55 (25.5%) for placebo-treated (OR 0.67, 95% CI 0.26-1.75). CONCLUSIONS Maternal sildenafil use had no effect on fetal growth velocity. Prospectively planned meta-analyses will determine whether sildenafil exerts other effects on maternal and fetal/neonatal wellbeing. TWEETABLE ABSTRACT Maternal sildenafil use has no beneficial effect on growth in early-onset FGR, but also no evidence of harm.
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Affiliation(s)
- K M Groom
- Liggins Institute, University of Auckland, Auckland, New Zealand.,National Women's Health, Auckland City Hospital, Auckland, New Zealand
| | - L M McCowan
- National Women's Health, Auckland City Hospital, Auckland, New Zealand.,Department of Obstetrics and Gynaecology, University of Auckland, Auckland, New Zealand
| | - L K Mackay
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - A C Lee
- Section of Epidemiology and Biostatistics, University of Auckland, Auckland, New Zealand
| | - G Gardener
- Mater Centre for Maternal Fetal Medicine, Mater Research Institute, Mater Mother's Hospital, University of Queensland, Brisbane, Qld, Australia
| | - J Unterscheider
- Department of Maternal Fetal Medicine, Royal Women's Hospital, Melbourne, Vic, Australia.,Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Vic, Australia
| | - R Sekar
- Department of Maternal Fetal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Qld, Australia
| | - J E Dickinson
- King Edward Memorial Hospital, Perth, WA, Australia.,Division of Obstetrics and Gynaecology, University of Western Australia, Perth, WA, Australia
| | - P Muller
- Director Maternal Fetal Medicine Service, Women's and Children's Hospital Adelaide, North Adelaide, SA, Australia
| | - R A Reid
- Christchurch Women's Hospital, Christchurch, New Zealand.,Department of Obstetrics and Gynaecology, University of Otago, Christchurch, New Zealand
| | - D Watson
- Women's and Children's Service, Townsville Hospital, Townsville, Qld, Australia
| | - A Welsh
- Royal Hospital for Women, Sydney, NSW, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, NSW, Australia
| | - J Marlow
- Maternal Fetal Medicine, Wellington Hospital, Wellington, New Zealand
| | - S P Walker
- Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Vic, Australia.,Mercy Hospital for Women, Melbourne, Vic, Australia
| | - J Hyett
- RPA Women and Babies, Royal Prince Alfred Hospital, Sydney, NSW, Australia.,Discipline of Obstetrics, Gynaecology and Neonatology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - J Morris
- Perinatal Research, Faculty of Medicine and Health, The Kolling Institute, The University of Sydney, Sydney, NSW, Australia
| | - P R Stone
- Department of Obstetrics and Gynaecology, University of Auckland, Auckland, New Zealand
| | - P N Baker
- Liggins Institute, University of Auckland, Auckland, New Zealand.,College of Life Sciences, University of Leicester, Leicester, UK
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15
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Yeom H, Lee Y, Ryu T, Noh J, Lee AC, Lee HB, Kang E, Song SW, Kwon S. Barcode-free next-generation sequencing error validation for ultra-rare variant detection. Nat Commun 2019; 10:977. [PMID: 30816127 PMCID: PMC6395625 DOI: 10.1038/s41467-019-08941-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 10/26/2018] [Accepted: 01/30/2019] [Indexed: 12/31/2022] Open
Abstract
The advent of next-generation sequencing (NGS) has accelerated biomedical research by enabling the high-throughput analysis of DNA sequences at a very low cost. However, NGS has limitations in detecting rare-frequency variants (< 1%) because of high sequencing errors (> 0.1~1%). NGS errors could be filtered out using molecular barcodes, by comparing read replicates among those with the same barcodes. Accordingly, these barcoding methods require redundant reads of non-target sequences, resulting in high sequencing cost. Here, we present a cost-effective NGS error validation method in a barcode-free manner. By physically extracting and individually amplifying the DNA clones of erroneous reads, we distinguish true variants of frequency > 0.003% from the systematic NGS error and selectively validate NGS error after NGS. We achieve a PCR-induced error rate of 2.5×10−6 per base per doubling event, using 10 times less sequencing reads compared to those from previous studies. Next generation sequencing has difficulty in detecting rare-frequency variants due to high sequencing errors. Here the authors present a barcode-free error validation method that physically extracts erroneous reads to identify true variants.
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Affiliation(s)
- Huiran Yeom
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yonghee Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Taehoon Ryu
- Department of Molecular and Genetical Engineering, Celemics Inc., 371-17, Gasan-dong, Geumcheon-gu, 08506, Seoul, Republic of Korea
| | - Jinsung Noh
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Amos Chungwon Lee
- Interdisciplinary Program for Bioengineering, Seoul National University, 08826, Seoul, Republic of Korea
| | - Han-Byoel Lee
- Department of Surgery, Seoul National University College of Medicine, Seoul National University Hospital Biomedical Research Institute, 03080, Seoul, Republic of Korea
| | - Eunji Kang
- Cancer Research Institute, Seoul National University, 03080, Seoul, Republic of Korea
| | - Seo Woo Song
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea. .,Department of Molecular and Genetical Engineering, Celemics Inc., 371-17, Gasan-dong, Geumcheon-gu, 08506, Seoul, Republic of Korea. .,Interdisciplinary Program for Bioengineering, Seoul National University, 08826, Seoul, Republic of Korea. .,Bio-MAX institute, Seoul National University, 08826, Seoul, Republic of Korea.
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16
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Song SW, Kim SD, Oh DY, Lee Y, Lee AC, Jeong Y, Bae HJ, Lee D, Lee S, Kim J, Kwon S. One-Step Generation of a Drug-Releasing Hydrogel Microarray-On-A-Chip for Large-Scale Sequential Drug Combination Screening. Adv Sci (Weinh) 2019; 6:1801380. [PMID: 30775230 PMCID: PMC6364496 DOI: 10.1002/advs.201801380] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 11/01/2018] [Indexed: 05/23/2023]
Abstract
Large-scale screening of sequential drug combinations, wherein the dynamic rewiring of intracellular pathways leads to promising therapeutic effects and improvements in quality of life, is essential for personalized medicine to ensure realistic cost and time requirements and less sample consumption. However, the large-scale screening requires expensive and complicated liquid handling systems for automation and therefore lowers the accessibility to clinicians or biologists, limiting the full potential of sequential drug combinations in clinical applications and academic investigations. Here, a miniaturized platform for high-throughput combinatorial drug screening that is "pipetting-free" and scalable for the screening of sequential drug combinations is presented. The platform uses parallel and bottom-up formation of a heterogeneous drug-releasing hydrogel microarray by self-assembly of drug-laden hydrogel microparticles. This approach eliminates the need for liquid handling systems and time-consuming operation in high-throughput large-scale screening. In addition, the serial replacement of the drug-releasing microarray-on-a-chip facilitates different drug exchange in each and every microwell in a simple and highly parallel manner, supporting scalable implementation of multistep combinatorial screening. The proposed strategy can be applied to various forms of combinatorial drug screening with limited amounts of samples and resources, which will broaden the use of the large-scale screening for precision medicine.
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Affiliation(s)
- Seo Woo Song
- Department of Electrical and Computer EngineeringSeoul National UniversitySeoul08826South Korea
| | - Su Deok Kim
- Department of Electrical and Computer EngineeringSeoul National UniversitySeoul08826South Korea
| | - Dong Yoon Oh
- Institutes of Entrepreneurial BioConvergenceSeoul National UniversitySeoul08826South Korea
| | - Yongju Lee
- Department of Electrical and Computer EngineeringSeoul National UniversitySeoul08826South Korea
| | - Amos Chungwon Lee
- Department of Mechanical Science and EngineeringUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
| | - Yunjin Jeong
- Department of Electrical and Computer EngineeringSeoul National UniversitySeoul08826South Korea
| | - Hyung Jong Bae
- Nano Systems InstituteSeoul National UniversitySeoul08826South Korea
| | - Daewon Lee
- Interdisciplinary Program in BioengineeringSeoul National UniversitySeoul08826South Korea
| | - Sumin Lee
- Department of Electrical and Computer EngineeringSeoul National UniversitySeoul08826South Korea
| | - Jiyun Kim
- School of Materials Science and EngineeringUlsan National Institute of Science and TechnologyUlsan44919South Korea
| | - Sunghoon Kwon
- Department of Electrical and Computer EngineeringSeoul National UniversitySeoul08826South Korea
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17
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Kim N, Choi S, Kim SM, Lee AC, Im K, Park HS, Kim JA, Kim K, Kim I, Chang YH, Lee DS. Monozygotic twins with shared de novo GATA2 mutation but dissimilar phenotypes due to differential promoter methylation. Leuk Lymphoma 2019; 60:1053-1061. [PMID: 30714451 DOI: 10.1080/10428194.2018.1516039] [Citation(s) in RCA: 3] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A revised WHO classification of hematopoietic neoplasm introduced the new category 'Myeloid Neoplasms with Germline Predisposition', reflecting the growing importance of genetic testing for myeloid neoplasms. Here, we investigated monozygotic twins with the same de novo mutation in GATA2 but different phenotypes. The patient suffering a bleeding tendency was diagnosed with myelodysplastic syndrome (MDS), and her monozygotic twin showed dysmegakaryopoietic features in the bone marrow. Targeted sequencing revealed the same germline mutation in GATA2, c.1192C > T, in both sisters and different somatic mutations in 14 genes between the sisters. The GATA2 mutation was absent in both parents, and their hemograms were normal. The methylation profile of the GATA2 promoter region was different between the twins, showing denser promoter methylation in the patient, correlated with MDS. Thus, we concluded that the twins had acquired a de novo GATA2 mutation but showed different phenotypes, possibly due to the critical role of epigenetic changes.
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Affiliation(s)
- Namhee Kim
- a Department of Laboratory Medicine , Seoul National University College of Medicine , Seoul , Republic of Korea
| | - Seongmin Choi
- b Division of Clinical Bioinformatics Biomedical Research Institute , Seoul National University Hospital , Seoul , Republic of Korea
| | - Sung-Min Kim
- c Cancer Research Institute, Seoul National University College of Medicine , Seoul , Republic of Korea
| | - Amos Chungwon Lee
- d Interdisciplinary program of Bioengineering , Seoul National University , Seoul , Republic of Korea
| | - Kyongok Im
- c Cancer Research Institute, Seoul National University College of Medicine , Seoul , Republic of Korea
| | - Hee Sue Park
- a Department of Laboratory Medicine , Seoul National University College of Medicine , Seoul , Republic of Korea
| | - Jung-Ah Kim
- a Department of Laboratory Medicine , Seoul National University College of Medicine , Seoul , Republic of Korea
| | - Kwangsoo Kim
- b Division of Clinical Bioinformatics Biomedical Research Institute , Seoul National University Hospital , Seoul , Republic of Korea
| | - Inho Kim
- e Department of Internal Medicine , Seoul National University College of Medicine , Seoul , Republic of Korea
| | - Yoon Hwan Chang
- f Department of Laboratory Medicine , Korea Cancer Center Hospital , Seoul , Republic of Korea
| | - Dong Soon Lee
- a Department of Laboratory Medicine , Seoul National University College of Medicine , Seoul , Republic of Korea.,c Cancer Research Institute, Seoul National University College of Medicine , Seoul , Republic of Korea
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18
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Kim S, Lee AC, Lee HB, Kim J, Jung Y, Ryu HS, Lee Y, Bae S, Lee M, Lee K, Kim RN, Park WY, Han W, Kwon S. PHLI-seq: constructing and visualizing cancer genomic maps in 3D by phenotype-based high-throughput laser-aided isolation and sequencing. Genome Biol 2018; 19:158. [PMID: 30296938 PMCID: PMC6176506 DOI: 10.1186/s13059-018-1543-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [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: 03/12/2018] [Accepted: 09/18/2018] [Indexed: 04/04/2023] Open
Abstract
Spatial mapping of genomic data to tissue context in a high-throughput and high-resolution manner has been challenging due to technical limitations. Here, we describe PHLI-seq, a novel approach that enables high-throughput isolation and genome-wide sequence analysis of single cells or small numbers of cells to construct genomic maps within cancer tissue in relation to the images or phenotypes of the cells. By applying PHLI-seq, we reveal the heterogeneity of breast cancer tissues at a high resolution and map the genomic landscape of the cells to their corresponding spatial locations and phenotypes in the 3D tumor mass.
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Affiliation(s)
- Sungsik Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea.,Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Amos Chungwon Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea.,Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Han-Byoel Lee
- Department of Surgery, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea
| | - Jinhyun Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yushin Jung
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Han Suk Ryu
- Department of Pathology, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea
| | - Yongju Lee
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sangwook Bae
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea.,Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Minju Lee
- Cancer Research Institute, Seoul National University, Seoul, 03080, Republic of Korea
| | - Kyungmin Lee
- Cancer Research Institute, Seoul National University, Seoul, 03080, Republic of Korea
| | - Ryong Nam Kim
- Cancer Research Institute, Seoul National University, Seoul, 03080, Republic of Korea
| | - Woong-Yang Park
- Samsung Genome Institute, Samsung Medical Center, Seoul, 06351, Republic of Korea.,Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 03063, Republic of Korea
| | - Wonshik Han
- Department of Surgery, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea. .,Cancer Research Institute, Seoul National University, Seoul, 03080, Republic of Korea.
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, 08826, Republic of Korea. .,Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, 08826, Republic of Korea. .,Seoul National University Hospital Biomedical Research Institute, Seoul National University Hospital, Seoul, 03080, Republic of Korea.
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19
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Oh DY, Na H, Song SW, Kim J, In H, Lee AC, Jeong Y, Lee D, Jang J, Kwon S. ELIPatch, a thumbnail-size patch with immunospot array for multiplexed protein detection from human skin surface. Biomicrofluidics 2018; 12:031101. [PMID: 30867857 PMCID: PMC6404946 DOI: 10.1063/1.5032170] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 04/12/2018] [Indexed: 06/09/2023]
Abstract
Proteins secreted by skin have great potential as biomarkers for interpreting skin conditions. However, inconvenience in handling and bulky size of existing methods are existing limitations. Here, we describe a thumb-nail sized patch with the array of microdisks which captures multiple proteins from the skin surface. Microdisks with antibody on the surface enable multiplexed immunoassay. By self-assembly, microdisks are placed into 2-dimensional arrays on adhesive tape. The proposed Enzyme-Linked Immunospot array on a Patch shows sufficient sensitivity for IL-1α, IL1RA, IL-17A, IFN-g, and TNF-α, while IL-6 and IL-1β are non-detectable in some cases. As demonstrations, we quantified cytokines from different skin regions and volunteers in a high-spatial-resolution.
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Affiliation(s)
| | | | | | | | - Hyunsoo In
- QuantaMatrix, Inc., Seoul 03122, South Korea
| | | | | | | | - Jisung Jang
- QuantaMatrix, Inc., Seoul 03122, South Korea
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Lee D, Lee AC, Han S, Bae HJ, Song SW, Jeong Y, Oh DY, Cho S, Kim J, Park W, Kwon S. Hierarchical shape-by-shape assembly of microparticles for micrometer-scale viral delivery of two different genes. Biomicrofluidics 2018; 12:031102. [PMID: 29774082 PMCID: PMC5935507 DOI: 10.1063/1.5030597] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 04/24/2018] [Indexed: 05/31/2023]
Abstract
Understanding tissue engineering using a bottom-up approach has been hindered by technical limitations because no platform can demonstrate the controlled formation of a heterogeneous population of cells in microscale. Here, we demonstrate hierarchical shape-by-shape assembly of virus-laden particles into larger ones to transfect two different genes on the seeded cells. We show that smaller daughter particles with different sizes and shapes can be assembled into the matching indentations of larger parent particles with different sizes and shapes. Then, we transfected a population of cells with two different gene-transfecting viruses, each of which was laden on the parent or daughter particles.
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Affiliation(s)
- Daewon Lee
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
| | - Amos Chungwon Lee
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
| | - Sangkwon Han
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Hyung Jong Bae
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Champaign, Illinois 61801, USA
| | - Seo Woo Song
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Yunjin Jeong
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Dong Yoon Oh
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, South Korea
| | - Seongkyu Cho
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Junhoi Kim
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 03080, South Korea
| | - Wook Park
- Department of Electronic Engineering, Kyung Hee University, Yongin-si, Gyeonggi-do 17104, South Korea
| | - Sunghoon Kwon
- Authors to whom correspondence should be addressed: and
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Hess PW, Becker P, Kaplan HB, Kyprianidis A, Lee AC, Neyenhuis B, Pagano G, Richerme P, Senko C, Smith J, Tan WL, Zhang J, Monroe C. Non-thermalization in trapped atomic ion spin chains. Philos Trans A Math Phys Eng Sci 2017; 375:rsta.2017.0107. [PMID: 29084886 PMCID: PMC5665787 DOI: 10.1098/rsta.2017.0107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/27/2017] [Indexed: 05/27/2023]
Abstract
Linear arrays of trapped and laser-cooled atomic ions are a versatile platform for studying strongly interacting many-body quantum systems. Effective spins are encoded in long-lived electronic levels of each ion and made to interact through laser-mediated optical dipole forces. The advantages of experiments with cold trapped ions, including high spatio-temporal resolution, decoupling from the external environment and control over the system Hamiltonian, are used to measure quantum effects not always accessible in natural condensed matter samples. In this review, we highlight recent work using trapped ions to explore a variety of non-ergodic phenomena in long-range interacting spin models, effects that are heralded by the memory of out-of-equilibrium initial conditions. We observe long-lived memory in static magnetizations for quenched many-body localization and prethermalization, while memory is preserved in the periodic oscillations of a driven discrete time crystal state.This article is part of the themed issue 'Breakdown of ergodicity in quantum systems: from solids to synthetic matter'.
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Affiliation(s)
- P W Hess
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - P Becker
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - H B Kaplan
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - A Kyprianidis
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - A C Lee
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - B Neyenhuis
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - G Pagano
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - P Richerme
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - C Senko
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - J Smith
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - W L Tan
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - J Zhang
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
| | - C Monroe
- Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, MD 20742, USA
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Abstract
The ability of Parkinsonian (PD) patients to control overt visual attention was investigated, by measuring reaction time to a visual stimulus presented at different distances (1.5 deg, 6 deg, and 12 deg) and directions (left or right) from a central fixation point. Prior to the onset of the target stimulus (a square), a cue stimulus appeared just above the fixation point. With equal probability, the arrow pointed to the left, or to the right, or was ambiguous (with two heads). On 20% of their presentations, the left and right arrows pointed in the direction opposite to where the target was to appear. Subjects were informed that 20% of cues would be misleading, and correcting lenses were used to optimise their visual acuity. In previous work with a similar paradigm, only one target eccentricity was used, and subjects were not refracted, leaving open the possibility that PD subjects had more difficulty in seeing the cues and targets. The eight PD subjects had longer reaction times than age-matched normal controls (and were relatively slower for the more eccentric targets), but made fewer errors in all conditions. In particular, they were more accurate than the controls on the presentations when the cue was misleading or ambiguous, suggesting that the PD group were ignoring the cue. It seems unlikely that the subjects discriminate the direction of the cues, given the use of optical correction, and they reported seeing the cues. Our data are consistent with those of other workers who have described a similar ‘disengagement of attention’ in PD (Clark et al, 1989 Neuropsychologia27 131 – 140) and attributed it to decreased catecholaminergic activity following destruction of midbrain structures (Wright et al, 1990 Neuropsychologia28 151 – 159).
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Abstract
This retrospective study uses discharge-level data to analyse and assess the situation of re-admissions within 15 days of discharge, for quality evaluation. The re-admission rate of the study period was 3.22%. Among those re-admission cases, 45.7% patients were re-admitted within five days of discharge, and 33.5% cases returned to hospital six to 10 days after discharge. The average length of stays of re-admissions (9.86 days for previous stay and 8.10 days for re-admitted stay) were both longer than the hospital's overall average (7.63 days) at the same period. Paediatric patients comprised the greatest number of re-admissions. Re-admissions were more likely to have higher percentage of emergency admission. Significant relationships were found between factors for re-admissions and patient characteristics (e.g. age and insurance status), admitted department, and diagnosis. Further investigation and strategies, combined with the application of severity adjustment technique to better monitor and avoid unnecessary re-admissions, need to be developed.
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Affiliation(s)
- K L Tsai
- Program in Health Science and Health Administration, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, TX 78412, USA
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Lee HB, Kim S, Lee KM, Jung Y, Lee AC, Kim J, Bae S, Ryu HS, Yoo TK, Moon HG, Noh DY, Kwon S, Han W. Abstract P1-02-01: Genomic analysis of single cells isolated by a pulse laser retrieval system. Cancer Res 2016. [DOI: 10.1158/1538-7445.sabcs15-p1-02-01] [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: 11/16/2022]
Abstract
Abstract
Background: Isolating tumor cells of interest and harvesting histologically pure samples is important for genomic studies. Laser capture microdissection (LCM) is an established method to obtain such purified cell populations for various applications including DNA, gene expression, and single cell analyses. However, LCM possesses problems such as limited optical resolution, cell fragmentation from dissection, and adherence of adjacent tissue to the cells which interrupts with single cell isolation from tissue sections. To overcome these obstacles, we developed a high-throughput pulse laser retrieval system which uses a wavelength that minimizes damage to the cellular content and is processed with a sacrificial layer that provides applicable optical resolution. The aim of this study was to evaluate the performance of the pulse laser retrieval system to provide appropriate samples for genomic analysis using breast cancer tissue.
Methods: An indium tin oxide (ITO) coated glass slide was prepared using fresh frozen breast cancer tissue sections of 4㎛ thickness and stained by hematoxylin and eosin. The slide was mounted on the cell isolation machine and imaging was performed with a charge-coupled device camera using a 20× lens. Following identification of the target cells by a pathologist, nano-second pulsed laser (wavelength= 1064nm) was irradiated on the target. Isolated cells were collected in a polymerase chain reaction tube and whole genome amplification (WGA) was carried out using Illustra GenomiPhi V2 DNA Amplification Kit (GE Healthcare Life Sciences, Pittsburgh, PA, USA). Amplified genomic DNA was fragmented and Illumina sequencing libraries were constructed. Sequencing was carried out to generate data with 0.1∼0.2× depth throughout the whole genome for each sample. Copy number variation (CNV) was analyzed by the Variable binning algorithm.
Results: Whole genome amplification was performed using bulk tissue and 10 captured single cells from the same specimen. No difference in amplification coverage was observed between the two samples. A CNV analysis of captured single cells revealed similar CNV profiles with those in a matched bulk tumor. Whole exome sequencing (WES) of captured single cells yielded a variant frequency of 15% at a read depth of 15× and 50M base coverage, compared to 0% at 100× and 50M for WES using bulk tumor and 0.5% at 1200× and 100K for targeted sequencing using bulk tumor. Laser capture was performed for DCIS and stromal cells from the same slide. CNV analysis of the two samples showed minimal CNV in normal stromal cells in contrast to DCIS where multiple CNVs were observed.
Conclusions: Newly developed pulse laser retrieval system is suitable for capturing single cells for genomic analysis of breast cancer. WGA, WES, and CNV analysis was successfully carried out using the captured single cells and showed no difference in profile compared to those performed with bulk tissue. This method may have the potential to replace LCM for certain applications such as single cell analyses.
Citation Format: Lee H-B, Kim S, Lee K-M, Jung Y, Lee AC, Kim J, Bae S, Ryu HS, Yoo T-K, Moon H-G, Noh D-Y, Kwon S, Han W. Genomic analysis of single cells isolated by a pulse laser retrieval system. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-02-01.
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Affiliation(s)
- H-B Lee
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - S Kim
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - K-M Lee
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - Y Jung
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - AC Lee
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - J Kim
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - S Bae
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - HS Ryu
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - T-K Yoo
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - H-G Moon
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - D-Y Noh
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - S Kwon
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
| | - W Han
- Seoul National University College of Medicine, Seoul, Republic of Korea; Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Electrical Engineering and Computer Science, Seoul, Republic of Korea; Institutes of Entrepreneurial BioConvergence, Seoul National University, Seoul, Republic of Korea
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Chen Q, Wei J, Tong M, Yu L, Lee AC, Gao YF, Zhao M. Associations between body mass index and maternal weight gain on the delivery of LGA infants in Chinese women with gestational diabetes mellitus. J Diabetes Complications 2015; 29:1037-41. [PMID: 26376766 DOI: 10.1016/j.jdiacomp.2015.08.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 07/31/2015] [Accepted: 08/20/2015] [Indexed: 02/05/2023]
Abstract
BACKGROUND Women with gestational diabetes mellitus (GDM) are at increased risk for maternal and fetal complications including delivery of large for gestational age (LGA) infants. Maternal body mass index (BMI) and excessive weight gain during pregnancy are associated with delivery of LGA infants. However, whether maternal BMI and weight gain are associated with LGA infants in women with GDM is unclear. BASIC PROCEDURES Data on 1049 pregnant women who developed GDM were collected from a university teaching hospital in China and retrospectively analyzed. Data included maternal BMI, weight gain, incidence of LGA and gestational week at diagnosis. MAIN FINDINGS The incidence of LGA infants was significantly associated with maternal BMI (p=0.0002) in women with GDM. The odds of delivery of LGA for obese or overweight pregnant women are 3.8 or 2 times more than normal weight pregnant women. The incidence of LGA infants was also significantly associated with maternal weight gain in women with GDM. The odds ratio of delivery of LGA for pregnant women with excessive weight gain was 3.3 times more than pregnant women with normal weight gain. The effect of weight gain was not significantly different between different maternal BMI. PRINCIPAL CONCLUSION The incidence of delivery of LGA infants in Chinese women with GDM who were overweight or obese is higher than Caucasians, Hispanic, and Asian-Americans. The effects of maternal BMI and weight gain on the delivery of LGA infants by women with GDM are additive.
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Affiliation(s)
- Qi Chen
- The Hospital of Obstetrics & Gynaecology, Fudan University, Shanghai, China; Department of Obstetrics & Gynaecology, The University of Auckland, Auckland, New Zealand
| | - J Wei
- Department of Obstetrics & Gynaecology, The University of Auckland, Auckland, New Zealand
| | - M Tong
- Department of Obstetrics & Gynaecology, The University of Auckland, Auckland, New Zealand
| | - L Yu
- Department of Anatomy with Radiology, The University of Auckland, Auckland, New Zealand
| | - A C Lee
- Section of Epidemiology and Biostatistics, School of Population Health, The University of Auckland, New Zealand
| | - Y F Gao
- The Hospital of Obstetrics & Gynaecology, Fudan University, Shanghai, China
| | - M Zhao
- Wuxi Maternity and Child Health Hospital, Nanjing Medical University, Wuxi, China.
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Godfrey DA, Chen K, Godfrey MA, Lee AC, Crass SP, Shipp D, Simo H, Robinson KT. Cochlear ablation effects on amino acid levels in the chinchilla cochlear nucleus. Neuroscience 2015; 297:137-59. [PMID: 25839146 DOI: 10.1016/j.neuroscience.2015.03.055] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [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: 12/15/2014] [Revised: 03/06/2015] [Accepted: 03/24/2015] [Indexed: 10/23/2022]
Abstract
Inner ear damage can lead to hearing disorders, including tinnitus, hyperacusis, and hearing loss. We measured the effects of severe inner ear damage, produced by cochlear ablation, on the levels and distributions of amino acids in the first brain center of the auditory system, the cochlear nucleus. Measurements were also made for its projection pathways and the superior olivary nuclei. Cochlear ablation produces complete degeneration of the auditory nerve, which provides a baseline for interpreting the effects of partial damage to the inner ear, such as that from ototoxic drugs or intense sound. Amino acids play a critical role in neural function, including neurotransmission, neuromodulation, cellular metabolism, and protein construction. They include major neurotransmitters of the brain - glutamate, glycine, and γ-aminobutyrate (GABA) - as well as others closely related to their metabolism and/or functions - aspartate, glutamine, and taurine. Since the effects of inner ear damage develop over time, we measured the changes in amino acid levels at various survival times after cochlear ablation. Glutamate and aspartate levels decreased by 2weeks in the ipsilateral ventral cochlear nucleus and deep layer of the dorsal cochlear nucleus, with the largest decreases in the posteroventral cochlear nucleus (PVCN): 66% for glutamate and 63% for aspartate. Aspartate levels also decreased in the lateral part of the ipsilateral trapezoid body, by as much as 50%, suggesting a transneuronal effect. GABA and glycine levels showed some bilateral decreases, especially in the PVCN. These results may represent the state of amino acid metabolism in the cochlear nucleus of humans after removal of eighth nerve tumors, which may adversely result in destruction of the auditory nerve. Measurement of chemical changes following inner ear damage may increase understanding of the pathogenesis of hearing impairments and enable improvements in their diagnosis and treatment.
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Affiliation(s)
- D A Godfrey
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA.
| | - K Chen
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - M A Godfrey
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - A C Lee
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - S P Crass
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - D Shipp
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - H Simo
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - K T Robinson
- Department of Neurology, University of Toledo College of Medicine, Mail Stop 1195, 3000 Arlington Avenue, Toledo, OH 43614, USA; Division of Otolaryngology and Dentistry, Department of Surgery, University of Toledo College of Medicine, 3000 Arlington Avenue, Toledo, OH 43614, USA
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27
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Lee AC. Neuroblastoma: the challenge remains. Singapore Med J 2012; 53:1-2. [PMID: 22252174 DOI: pmid/22252174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Mullen R, Macaskill EJ, Khalil A, Elseedawy E, Brown DC, Lee AC, Purdie C, Jordan L, Thompson AM. P3-12-04: Involved Anterior Margins after Breast Conserving Surgery: Is Re-Excision Required? Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p3-12-04] [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: 11/16/2022]
Abstract
Abstract
Background: Complete tumour excision in breast conserving surgery (BCS) is critical for successful treatment; involved circumferential resection margins are associated with increased disease recurrence. However, the importance of an involved anterior margin is less clear. The purpose of this study was to audit an aggressive approach to involved anterior margins and hence assess whether anterior margin re-excision yields clinical benefit.
Material and Methods: A retrospective case note and pathology review was performed for all patients who underwent BCS between 2006 and 2010 through a single cancer centre. An involved margin was defined as <1mm clearance of invasive or in situ breast cancer. Results: 1667 patients underwent BCS for invasive and/or in-situ disease, of whom 114 (6.8%) underwent re-excision, most commonly for mixed invasive and in-situ pathology. The annual re-excision rate rose significantly (p<0.001), with no change in whole tumour diameter, specimen weight or specimen volume. A total of 170 involved margins were identified: most commonly the anterior margin (59 margins, 30.6%) followed by the posterior (39 22.9%) or inferior (31, 18.3%) margin. Patients with anterior margin involvement were more likely to have grade 3 invasive disease (p=0.0323) but less likely to have residual disease found at re-excision (2/49 vs. 32/101 margins, p=0.0033); there were no differences when in-situ characteristics were compared.
Conclusions: Re-excision of involved anterior margins rarely excises residual disease and may be unnecessary. Multidisciplinary teams should consider whether further therapy for an involved anterior margin is required on a patient by patient basis.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-12-04.
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Affiliation(s)
- R Mullen
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - EJ Macaskill
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - A Khalil
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - E Elseedawy
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - DC Brown
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - AC Lee
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - C Purdie
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - L Jordan
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
| | - AM Thompson
- 1Ninewells Hospital, Dundee, United Kingdom; Perth Royal Infirmary, Perth, United Kingdom
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29
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Abstract
BACKGROUND This study was designed to assess clinical and functional outcomes associated with switching to duloxetine treatment in patients with major depressive disorder (MDD) experiencing emotional and painful physical symptoms in their current episode. METHODS In this 8-week, multinational, multicentre, single-arm, open-label clinical trial, 242 MDD patients were switched to duloxetine 60 mg/day after selective serotonin reuptake inhibitor (SSRI) or serotonin and norepinephrine reuptake inhibitor (SNRI) treatment. The primary analysis compared mean change from baseline in Brief Pain Inventory-Modified Short Form (BPI-SF) interference score between initial responders [≥ 50% reduction from baseline on the 17-item Hamilton Depression Rating Scale (HAMD(17)) Maier subscale] and initial non-responders after 4 weeks. Initial responders continued with duloxetine 60 mg/day. Initial non-responders received duloxetine 120 mg/day for the remaining 4 weeks. Depression, pain, anxiety and functional outcomes were also compared after 8 weeks. RESULTS BPI-SF interference decreased from baseline in initial responders (n = 108) and initial non-responders (n = 85) after 4 weeks of duloxetine treatment, with greater reductions in initial responders [BPI-SF mean difference in reduction: 1.01 (95% CI 0.42-1.61); p < 0.001]. Reductions in pain interference favouring initial responders were also apparent after 8 weeks [0.68 (95% CI: 0.03-1.33); p = 0.042]. Depression, pain, anxiety and function improved over 8 weeks across patient groups. CONCLUSIONS Elements of core mood and pain are important residual symptoms following poor treatment response in MDD. Early improvement in these symptoms after switching to duloxetine indicated an increased chance of functional recovery.
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Affiliation(s)
- D Sagman
- Lilly Research Laboratories, Eli Lilly Canada, Toronto, ON, Canada.
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Alhamoruni A, Lee AC, Wright KL, Larvin M, O'Sullivan SE. Pharmacological effects of cannabinoids on the Caco-2 cell culture model of intestinal permeability. J Pharmacol Exp Ther 2010; 335:92-102. [PMID: 20592049 DOI: 10.1124/jpet.110.168237] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Activation of cannabinoid receptors decreases emesis, inflammation, gastric acid secretion, and intestinal motility. However, the effects of cannabinoids on intestinal permeability have not yet been established. The aim of the present study is to examine the effects of cannabinoids on intestinal permeability in an in vitro model. Caco-2 cells were grown until fully confluent on inserts in 12-well plates. Transepithelial electrical resistance (TEER) measurements were made as a measure of permeability. EDTA (50 μM) was applied to reversibly increase permeability (reduce TEER). The effects of cannabinoids on permeability in combination with EDTA, or alone, were assessed. Potential target sites of action were investigated using antagonists of the cannabinoid (CB)(1) receptor, CB(2) receptor, transient receptor potential vanilloid subtype 1 (TRPV1), peroxisome proliferator-activated receptor (PPAR)γ, PPARα, and a proposed cannabinoid receptor. When applied to the apical or basolateral membrane of Caco-2 cells, Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD) enhanced the speed of recovery of EDTA-induced increased permeability. This effect was sensitive to cannabinoid CB(1) receptor antagonism only. Apical application of endocannabinoids caused increased permeability, sensitive to cannabinoid CB(1) receptor antagonism. By contrast, when endocannabinoids were applied basolaterally, they enhanced the recovery of EDTA-induced increased permeability, and this involved additional activation of TRPV1. All cannabinoids tested increased the mRNA of the tight junction protein zona occludens-1, but only endocannabinoids also decreased the mRNA of claudin-1. These findings suggest that endocannabinoids may play a role in modulating intestinal permeability and that plant-derived cannabinoids, such as THC and CBD, may have therapeutic potential in conditions associated with abnormally permeable intestinal epithelium.
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Affiliation(s)
- A Alhamoruni
- School of Graduate Entry Medicine and Health, Royal Derby Hospital, University of Nottingham, Nottingham, United Kingdom
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31
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Lee AC. Bruises, blood coagulation tests and the battered child syndrome. Singapore Med J 2008; 49:445-9; quiz 450. [PMID: 18581014 DOI: pmid/18581014] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Cutaneous bruises are a common symptom and a sign of injury and blood coagulation disorders in childhood. A carefully-taken history, coupled with a thorough physical examination, would lead to the diagnosis, or guide the clinician to the necessary laboratory investigations. Most children suffering from non-accidental injury can have their diagnosis established on clinical grounds alone and do not require laboratory investigation. An initial screening with full blood counts, prothrombin time and activated partial thromboplastin time will be adequate in most cases if laboratory investigation is indicated, but the clinician must be aware of the limitations of these tests. The finding of an abnormal coagulation test does not exclude child abuse as it can be a consequence of maltreatment, or the two conditions may coexist. Whenever necessary, the opinion of a haematologist should be sought in order to obtain an accurate diagnosis, which is essential for subsequent management and the prevention of further injury in the case of child abuse.
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Affiliation(s)
- A C Lee
- Children's Haematology & Cancer Centre, East Shore Medical Centre, 319 Joo Chiat Place, Singapore.
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Mofidi R, Lee AC, Madhavan KK, Garden OJ, Parks RW. The selective use of magnetic resonance cholangiopancreatography in the imaging of the axial biliary tree in patients with acute gallstone pancreatitis. Pancreatology 2008; 8:55-60. [PMID: 18253063 DOI: 10.1159/000115667] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2007] [Accepted: 06/21/2007] [Indexed: 12/11/2022]
Abstract
BACKGROUND Magnetic resonance cholangiopancreatography (MRCP) is an emerging modality in the management of acute gallstone pancreatitis (AGP). The aim of this study was to assess the impact following the introduction of MRCP in the management of AGP in a tertiary referral unit. METHODS Patients presenting with AGP from January 2002 to December 2004 were reviewed to assess the impact of the introduction of MRCP in June 2003. The indication for MRCP was suspected common bile duct (CBD) stones in the absence of biliary sepsis. Definitive treatment for AGP was laparoscopic cholecystectomy, with endoscopic retrograde cholangiopancreatography (ERCP) and sphincterotomy reserved for patients unfit for cholecystectomy and those with biliary sepsis. RESULTS 249 patients were identified of whom 36 (14.5%) underwent ERCP and sphincterotomy as definitive treatment. 96 patients with a non-dilated CBD and normal or resolving liver function tests proceeded to laparosocopic cholecystectomy and intraoperative cholangiogram (IOC), 8 (8.5%) of whom had CBD stones intraoperatively. Eleven patients underwent cholecystectomy during pancreatic necrosectomy. Of those undergoing preoperative diagnostic biliary tract imaging, ERCP was undertaken in 57 patients and MRCP in 49 patients. There was no significant difference in serum bilirubin levels [ERCP 43 mmol/l (18-204) vs. MRCP 39 mmol/l (24-180), p = NS] or the proportion of patients with CBD stones [ERCP 10 (17.5%) vs. MRCP 7 (14.2%), p = NS] between the two groups. Patients who underwent MRCP had a shorter median hospital stay [MRCP 5 days (range: 3-14) vs. ERCP 9 days (range: 4-20), p < 0.01] and higher rate of cholecystectomy during the index admission (MRCP 83.3% vs. ERCP 67.2%, p < 0.05). There was a high degree of correlation between preoperative MRCP results and findings of subsequent IOC or therapeutic ERCP (area under ROC curve: 0.94). CONCLUSIONS MRCP is an accurate modality for imaging the axial biliary tree in patients with AGP. Selective use of MRCP reduces the need for ERCP and results in shorter hospital stay. and IAP.
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Affiliation(s)
- R Mofidi
- Department of Clinical and Surgical Sciences (Surgery), University of Edinburgh, Edinburgh, UK
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Mofidi R, Lee AC, Madhavan KK, Garden OJ, Parks RW. Prognostic factors in patients undergoing surgery for severe necrotizing pancreatitis. World J Surg 2007; 31:2002-7. [PMID: 17687599 DOI: 10.1007/s00268-007-9164-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Pancreatic necrosectomy remains an important treatment modality for the management of infected pancreatic necrosis but is associated with significant mortality. The aim of this study was to identify factors associated with mortality following pancreatic necrosectomy. Patients who underwent pancreatic necrosectomy from January 1995 to December 2004 were reviewed. The association between admission, preoperative and postoperative variables, and mortality was assessed using logistic regression analysis. A total of 1248 patients presented with acute pancreatitis, of whom 94 (7.5%) underwent pancreatic necrosectomy (51 men, 43 women). The preoperative median Acute Physiology, Age, and Chronic Health Evaluation (APACHE II) score was 9 (range 2-19). The median cumulative organ dysfunction score was 2 (0-9) preoperatively and 4 (1-11) postoperatively. In all, 23 patients (24.5%) died. Those who died were older than the survivors; the ages (median and range) were 69 years (40-80 years) versus 52 years (19-79 years) (p < 0.05). They also had higher admission APACHE II scores (median and range): 14 (12-19) versus 9 (2-22) (p < 0.001). There were significant associations between preoperative (p < 0.01) and postoperative (p < 0.01) Marshall scores and mortality following pancreatic necrosectomy. The presence of the systemic inflammatory response syndrome (SIRS) during the first 48 hours (p < 0.01) and the time between presentation and necrosectomy (p < 0.01) were independent predictors of survival. Pancreatic necrosectomy is associated with higher mortality in patients with increased APACHE II scores, early persistent SIRS, and unresolved multiorgan dysfunction. Necrosectomy is associated with poorer outcome when performed within 2 weeks of presentation.
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Affiliation(s)
- R Mofidi
- Department of Clinical and Surgical Sciences, University of Edinburgh, Royal Infirmary of Edinburgh, Old Dalkeith Road, Edinburgh, UK
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Kennedy LJ, Davison LJ, Barnes A, Short AD, Fretwell N, Jones CA, Lee AC, Ollier WER, Catchpole B. Identification of susceptibility and protective major histocompatibility complex haplotypes in canine diabetes mellitus. ACTA ACUST UNITED AC 2006; 68:467-76. [PMID: 17176436 DOI: 10.1111/j.1399-0039.2006.00716.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [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: 11/28/2022]
Abstract
Diabetes mellitus occurs spontaneously in dogs, which is believed to have an autoimmune component and to be a model of human latent autoimmune diabetes of adults (LADA). Some dog breeds (e.g. Samoyed) are particularly predisposed, whereas others (e.g. Boxer) are highly resistant. With the completion of the Dog Genome Assembly, comparative genomic studies of complex diseases in dogs, including diabetes, could provide an important investigative approach into such disorders. Type 1 diabetes in humans is strongly associated with major histocompatibility complex (MHC) class II polymorphisms. We have investigated whether canine dog leucocyte antigen (DLA) class II haplotypes are associated with diabetes. DNA from 460 cases and 1047 controls were genotyped for DLA-DRB1, DLA-DQA1 and DLA-DQB1 using sequence-based typing. Three DLA haplotypes, DRB1*009/DQA1*001/DQB1*008, DRB1*015/DQA1*0061/DQB1*023 and DRB1*002/DQA1*009/DQB1*001, were found at significantly increased frequency in cases with diabetes compared with controls. One DLA-DQ haplotype, DQA1*004/DQB1*013, was significantly reduced in cases with diabetes. Further analysis showed that DQA1 alleles carrying arginine at codon 55 of DQA1 were increased in dogs with diabetes. To our knowledge, this is the first report of a comparative study of MHC and diabetes in a non-rodent species. Since no laboratory model of LADA exists and dogs and humans share similar environments, further research into canine diabetes is warranted.
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Affiliation(s)
- L J Kennedy
- Centre for Integrated Genomic Medical Research, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK.
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Abstract
The optical spectra of yeast cells in phosphate buffer saline (PBS) were analyzed with an optical UV-vis sensor based on a shallow p(+)n junction realized in a low doped n-type epitaxial silicon layer grown on a strongly doped n(+) substrate. The presence of the n/n(+) interface allows a significantly enhanced sensitivity, due to an increased collection of carriers photogenerated both by short and large wavelengths in the range 250...800 nm. In our experiments the optical absorption of yeast cells was investigated in the wavelength range 250...500 nm as a function of the cells concentration in PBS in the range of 6 x 10(6)-2 x 10(8) cells/ml. The main absorption peaks were found at 310, 350, 400 and 427 nm, respectively. A significant red shift of the wide absorption band at 427 nm has been observed when increasing cell concentration. This red shift behaviour was nonlinear, with saturation observed for yeast concentrations larger than 5 x 10(7) cells/ml. The half-peak bandwidth of this peak also showed a most significant nonlinear variation. These findings suggest that monitoring the parameters of the absorption band at 427 nm versus cells concentration could be used, e.g. using a dedicated integrated spectrometric microsystem, for fast quantitative measurements of yeast cell concentrations in various bio-samples, with possible applications in the food industry.
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Affiliation(s)
- M Bercu
- Faculty of Physics, University of Bucharest, Bucharest, Romania.
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Chicken DW, Kocjan G, Falzon M, Lee AC, Douek M, Sainsbury R, Keshtgar MRS. Intraoperative touch imprint cytology for the diagnosis of sentinel lymph node metastases in breast cancer. Br J Surg 2006; 93:572-6. [PMID: 16550634 DOI: 10.1002/bjs.5289] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [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: 11/10/2022]
Abstract
Abstract
Background
Intraoperative detection of sentinel lymph node (SLN) metastases enables the surgeon to take an immediate decision to proceed to completion axillary lymph node dissection (ALND). The aim of this study was to determine the accuracy of touch imprint cytology (TIC) for the diagnosis of SLN metastases in sentinel nodes from women with breast cancer.
Methods
Touch imprints from 235 sentinel nodes in 133 women with breast cancer were diagnosed by cytopathology and compared with definitive histopathology results. After a feasibility study, a real-time study was performed with the surgeon proceeding to ALND based on the TIC diagnosis. The clinical opinion of the operating surgeon as to whether the SLN appeared to contain metastases was recorded, as was the time taken for the result to be available.
Results
TIC detected metastases with a sensitivity of 81·1 per cent and a specificity of 100 per cent. False-negative TIC diagnoses were associated with micrometastases and lobular carcinoma. The majority of false-negative diagnoses were due to sampling rather than interpretation errors. Clinical assessment of sentinel nodes had a sensitivity of 64·3 per cent and a specificity of 87·6 per cent.
Conclusion
TIC is feasible and enables the rapid diagnosis of SLN metastases with an acceptable accuracy for clinical use in ductal carcinoma of the breast.
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Affiliation(s)
- D W Chicken
- Academic Department of Surgery, Royal Free and University College Medical School, University College London, UK
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Glassinger E, Lee AC, Raphael RM. Electromechanical effects on tether formation from lipid membranes: a theoretical analysis. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 72:041926. [PMID: 16383439 DOI: 10.1103/physreve.72.041926] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 05/18/2005] [Indexed: 05/05/2023]
Abstract
The material properties of biomembranes can be measured by forming a tether, a thin bilayer tube that extends from the membrane surface. Recent experiments have demonstrated that the force required to maintain a tether is sensitive to the transmembrane potential. As a first approach towards understanding this phenomenon, a thermodynamic analysis of the influence of electrical fields on tether formation from an aspirated lipid vesicle is developed. The analysis considers contributions from Maxwell stresses as well as two forms of electromechanical coupling: coupling between the electric field and curvature strain (flexoelectric coupling) and between the electric field and areal strain (piezoelectric coupling). Predictions of equilibrium tether conformations are obtained numerically. For expected values of the dimensionless coupling parameters, flexoelectric coupling alters the force required to form a tether of a given length, while piezoelectric coupling and Maxwell forces do not greatly change the force versus tether length behavior. The results of this analysis indicate that tether experiments have the potential to characterize electromechanical coupling in both synthetic and cellular membranes.
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Affiliation(s)
- E Glassinger
- Department of Bioengineering, MS-142, Rice University, Houston, Texas 77251, USA
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Peters IR, Helps CR, Lait PL, Harris C, Lee AC, Jones CA, Hall EJ, Day MJ. Detection of allelic variants of the canine IGHA gene by fluorescence resonance energy transfer melting temperature examination. J Immunol Methods 2005; 304:60-7. [PMID: 16140319 DOI: 10.1016/j.jim.2005.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2005] [Revised: 05/24/2005] [Accepted: 06/08/2005] [Indexed: 11/21/2022]
Abstract
The fluorescence resonance energy transfer (FRET) dual hybridisation probe system has been used for the detection of the accumulation of target DNA during real-time PCR and for the identification of nucleotide polymorphisms through examination of melt curves. This system involves the use of two oligonucleotide probes which are located close to each other and are complementary to an internal segment of a target DNA of interest. Four allelic variants of the gene encoding the hinge region of the immunoglobulin A (IgA) heavy chain (IGHA) have been so far identified in the dog and this variability is due to a combination of single nucleotide polymorphisms and insertion/deletion of nucleic acid motifs. An individual dog may be homozygous or heterozygous for these allelic variants. The purpose of this study was to develop a FRET-based dual probe melting temperature assay to identify the alleles present within an individual dog and to use this assay to determine the frequency of the four allelic variants in different breeds within the canine population. A single pair of oligonucleotide probes were designed that were able to discriminate between the four allelic variants in both homozygous and heterozygous individuals. The genotype of 96 DNA samples obtained from various purebreeds of dogs was determined using this FRET assay. The frequency of each allele differed between the breed groups. The results of this study indicate that it is possible to distinguish relatively complex gene polymorphisms using a single set of oligonucleotide probes. Furthermore, any future comparison of IGHA genotypes between normal and diseased dog populations must take into account the breed variation in allelic frequency.
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Affiliation(s)
- I R Peters
- School of Clinical Veterinary Science, University of Bristol, Langford House, Langford, Bristol BS40 5DU, UK.
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Abstract
The visual perception of size in different regions of external space was studied in Parkinson's disease (PD). A group of patients with worse left-sided symptoms (LPD) was compared with a group with worse right-sided symptoms (RPD) and with a group of age-matched controls on judgements of the relative height or width of two rectangles presented in different regions of external space. The relevant dimension of one rectangle (the 'standard') was held constant, while that of the other (the 'variable') was varied in a method of constant stimuli. The point of subjective equality (PSE) of rectangle width or height was obtained by probit analysis as the mean of the resulting psychometric function. When the standard was in left space, the PSE of the LPD group occurred when the variable was smaller, and when the standard was in right space, when the variable was larger. Similarly, when the standard rectangle was presented in upper space, and the variable in lower space, the PSE occurred when the variable was smaller, an effect which was similar in both left and right spaces. In all these experiments, the PSEs for both the controls and the RPD group did not differ significantly, and were close to a physical match, and the slopes of the psychometric functions were steeper in the controls than the patients, though not significantly so. The data suggest that objects appear smaller in the left and upper visual spaces in LPD, probably because of right hemisphere impairment.
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Affiliation(s)
- J P Harris
- Department of Psychology, University of Reading, Whiteknights, Reading RG6 6AL, UK.
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Lee AC, Robbins TW, Owen AM. Episodic memory meets working memory in the frontal lobe: functional neuroimaging studies of encoding and retrieval. Crit Rev Neurobiol 2003; 14:165-97. [PMID: 12645957] [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: 03/01/2023]
Abstract
Recent functional-neuroimaging studies have provided a wealth of new information suggesting that regions of the prefrontal cortex play a role in episodic memory encoding and retrieval. This review seeks to evaluate the results of these studies in the context of one general model that has proposed that the left prefrontal cortex is preferentially involved in episodic memory encoding, whereas the right prefrontal cortex is preferentially involved in episodic memory retrieval, irrespective of the type (e.g., modality) of information being remembered. The origins of this framework are considered in some detail and then all relevant functional-neuroimaging studies are critically reviewed. The results of this review fail to provide support for the functional-asymmetry model, suggesting instead that episodic memory encoding and retrieval may actually involve similar regions of the lateral prefrontal cortex when all factors relating to the type of stimulus material (i.e., modality), are appropriately controlled.
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Affiliation(s)
- A C Lee
- MRC Cognition and Brain Sciences Unit, 15 Chaucer Road, Cambridge CB2 2EF, UK.
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Abstract
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias. Clinical trials are required to establish the best method of repair for this common condition.
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Affiliation(s)
- C A Courtney
- University Department of Surgery, Western Infirmary, G11 6NT, Glasgow, UK
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Lee AC, Harris JP, Atkinson EA, Nithi K, Fowler MS. Dopamine and the representation of the upper visual field: evidence from vertical bisection errors in unilateral Parkinson's disease. Neuropsychologia 2002; 40:2023-9. [PMID: 12207999 DOI: 10.1016/s0028-3932(02)00055-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [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: 11/24/2022]
Abstract
It has been suggested that dopamine is an important neurotransmitter in the brain mechanisms which represent the upper visual field. This idea was tested with a vertical line bisection task in unilateral Parkinson's disease. Stimuli of a range of lengths were presented on a large screen in three positions (left, centre and right) and at two viewing distances (0.6 and 1.5m). The patients, who were compared with a group of normal age-matched controls, comprised 16 sufferers from predominantly unilateral disease, 8 with more severe left-sided symptoms (LPD) and 8 with more severe right-sided symptoms (RPD). The LPD group consistently set the bisecting cursor below the midpoint of the stimulus lines, and their bisection error became larger as the length of the line increased. In contrast, the controls set the cursor above the midpoint of the line, an error which also increased with line length. The settings of the RPD group were similar to those of the controls. The results suggest altitudinal neglect in left unilateral PD, and support the hypothesis of dopaminergic involvement in the coding of upper visual space, with the proviso that the perceptual component of this involves the right hemisphere in humans.
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Affiliation(s)
- A C Lee
- Department of Psychology, University of Reading, Whiteknights, UK.
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Lee AC. The demand for children as a factor in fertility trends. Popul Forum 2002:19-21. [PMID: 12342114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Abstract
In 1974, using the rabbit as a model, we began long-term experiments designed to help in the evaluation of the hazards to man from extended exposure to heavy ions in space. Such exposure would occur, for example, during the construction of solar power stations in stationary orbits or on round trips to Mars. Our experiments with 400 MeV/nucleon Ne ions and 570 MeV/nucleon Ar ions have shown that true late effects of a degenerative nature are manifested only years after irradiation. At the appropriate doses (the high end of the experimental dose range), the magnitudes of the late effects are comparable with those encountered in human patients given radiation therapy with neutrons. Such comparisons show that the rabbit experiments are applicable to man. Given that basis, the results from the low end of the experimental dose range lead to the conclusion that astronauts subjected to the radiation fluxes anticipated during flights of the above duration could experience late radiation effects one or more decades after exposure. Late degenerative changes will occur in tissues of the central nervous system, terminally differentiating systems and stem cell populations. The studies also indicate that individual tissues may be "prematurely aged" by radiation in the sense that the "life spans" of those tissues can be decreased without the appearance of malignancies.
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Affiliation(s)
- J T Lett
- Department of Radiology and Radiation Biology, Colorado State University, Fort Collins, Colorado 80523, USA
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Abstract
The aim of this study was to evaluate the role of dynamic imaging in sentinel lymph node (SLN) biopsy in breast cancer. Patients with T1/T2, N0 invasive breast cancer underwent SLN localisation using intra-dermal injection of 15 MBq of 99mTc-nanocolloid. Gamma camera anterior-oblique dynamic imaging commenced simultaneously with tracer administration for 45 min, and was followed by anterior and lateral static imaging. Dynamic imaging data was reformatted into image files of different time-frames. Patterns of uptake were analysed using the sequences of dynamic frames and time-activity curve (TAC). SLN localisation was successful in 70/73 studies (96%) in 72 patients. Imaging information was present within the first 15 min of dynamic imaging in 67/70 studies (96%). Critical analysis of dynamic data helped to differentiate true SLN from secondary echelon nodes in eight studies and transient foci of radioactivity in six studies. In 17 studies, SLN contained metastatic disease. The detection of SLN metastasis was independent from the use of dynamic imaging. Dynamic imaging improves the interpretation of preoperative SLN imaging for breast cancer, but does not contribute significantly to the successful detection of SLN. Hence, preoperative dynamic imaging is not necessary in SLN biopsy for breast cancer.
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Affiliation(s)
- A C Lee
- Institute of Nuclear Medicine, Royal Free and University College Medical School, Middlesex Hospital, London W1N 8AA, UK.
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Abstract
A group of patients with left-sided symptoms of Parkinson's disease (LPD) was compared with a group of patients with right-sided symptoms (RPD) and with a group of healthy age-matched controls on body-scaled judgements of aperture width. Participants judged whether or not they would fit through a life-sized schematic doorway shown on a large screen. A staircase technique was used to find the door width for which 50% of the judgements were positive. The ratio between this measure and the width of the participant's body at the shoulders (the aperture to shoulder - A/S ratio) was calculated. The A/S ratio was approximately 1.5 in the LPD group, approximately 0.9 in the RPD group, and approximately 1.1 in the control group, suggesting that the visual representation of the doorway (or that of its relationship to perceived body-size) is compressed in LPD (and perhaps expanded in RPD). The A/S ratios were invariant with viewing distance (0.6 or 1.5 m), the contrast polarity of the display (white on dark, or vice versa) and the doorway surround (blank, or vertical or horizontal stripes). The findings are discussed with reference to the neural representation of external space and of the body, and to the motor problems of Parkinson's disease.
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Affiliation(s)
- A C Lee
- Department of Psychology, University of Reading, Earley Gate, Whiteknights, Reading RG6 6AL, UK.
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Abstract
The perception of extrapersonal space in Parkinson's disease was examined with two line bisection tasks. One was a conventional pencil and paper test, the line bisection section of the Behavioural Inattention Test. In the other, the stimuli were displayed on a large (2x2.4 m) screen and varied in length (48-480 mm) and also in location on the screen (left, centre and right). They were presented at two viewing distances (0.6 and 1.5 m). Subjects remotely adjusted the position of a cursor until it appeared to bisect the stimulus line, using two push-buttons, one in each hand. The PD participants (n=18) had a marked asymmetry of motor symptoms. They were divided into two groups, those with predominantly left-sided motor symptoms (LPD, n=9), and those with predominantly right-sided motor symptoms (RPD, n=9). The control group (n=9) were all right-handed. No significant differences between the groups were found on the BIT bisection task. In contrast, when the stimuli were presented on the screen, LPD subjects showed a significant rightward bias in their settings of the cursor, particularly for lines on the left and centre of the screen, which was greater, the longer the stimulus line. The RPD group bisected lines slightly to the left, in common with the control group (pseudo-neglect). In a second experiment, Parkinsonian subjects repeated this task, but with the buttons reversed between the hands, so that the cursor was moved to the left by the right hand, and vice versa, but the pattern of results was the same as in the first experiment. The data suggest a small but reliable neglect in left hemiparkinson's disease, which is contralateral to the non-dominant (and probably worse affected) hemisphere. The dissociation between the response and the bisection error suggests a visuospatial impairment in LPD.
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Affiliation(s)
- A C Lee
- Department of Psychology, University of Reading, Whiteknights, RG6 6AL, Reading, UK.
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Chan GC, Leung YL, Shing MM, Luk CW, Ling SC, Lee AC. Does a "false negative" MIBG scan predict a better outcome in neuroblastoma patients? Med Pediatr Oncol 2001; 37:155. [PMID: 11496360 DOI: 10.1002/mpo.1190] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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