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Lee KH, Yeh JT, Wu ML, Yeh WY, Lip GYH, Chiang CE, Chen CH, Cheng HM. Oral anticoagulants and cognitive impairment in patients with atrial fibrillation: A systematic review with meta-analysis and trial sequential analysis. Thromb Res 2024; 238:132-140. [PMID: 38704897 DOI: 10.1016/j.thromres.2024.04.032] [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: 02/28/2024] [Revised: 04/22/2024] [Accepted: 04/29/2024] [Indexed: 05/07/2024]
Abstract
BACKGROUND This systematic review assesses the likelihood of developing dementia and cognitive impairment in patients with atrial fibrillation (AF) receiving non-vitamin K antagonist oral anticoagulants (NOACs) as opposed to vitamin K antagonists (VKAs). METHODS We performed a systematic review with meta-analysis and trial sequential analysis (TSA), which encompassed both randomized controlled trials (RCTs) and observational studies. The objective was to assess the impact of NOACs and VKAs on the incidence of dementia in individuals diagnosed with AF. RESULTS Out of 1914 studies that were screened, 31 studies were included in the final analysis, which consisted of nine RCTs or their subsequent post-hoc analyses, in addition to 22 observational studies. The meta-analysis shows that NOACs were associated with a decreased probability of developing dementia of any cause [Rate Ratio (RR): 0.88; 95 % confidence interval (95 % CI): 0.82-0.94], especially in patients below the age of 75 (RR: 0.78; 95 % CI: 0.73-0.84). Consistent patterns were observed across all forms of dementia and cognitive function decline. The overall evidence indicates notable variability in the outcome with a moderate-to-low degree of certainty. The TSA suggests that the total sample size of the included trials (155,647 patients) was significantly smaller than the required information size of 784,692 patients to discern the true effect of NOAC versus VKA in terms of reducing dementia risk. CONCLUSION NOACs may reduce the likelihood of developing dementia in patients with AF, particularly in those under the age of 75. This review highlights the urgent necessity for thorough research to determine the efficacy of NOACs in safeguarding cognitive health.
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Affiliation(s)
- Kun-Han Lee
- Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan; Center for Evidence-based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jiunn-Tyng Yeh
- Center for Evidence-based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Center for Artificial Intelligence in Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Meng-Lun Wu
- Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Wan-Yu Yeh
- Center for Evidence-based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Gregory Y H Lip
- Liverpool Centre for Cardiovascular Science, University of Liverpool, Liverpool John Moores University and Liverpool Heart & Chest Hospital, Liverpool, UK; Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - Chern-En Chiang
- Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; General Clinical Research Center, Taipei Veterans General Hospital, Taipei, Taiwan; College of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan
| | - Chen-Huan Chen
- Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan; ReShining Clinic, Taipei, Taiwan
| | - Hao-Min Cheng
- Center for Evidence-based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan; College of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan; Ph.D. Program of Interdisciplinary Medicine (PIM), National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan; Division of Faculty Development, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Public Health and Community Medicine Research Center, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan.
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Lee KH, Chen YF, Yeh WY, Yeh JT, Yang TH, Chou CY, Chang YL, Wang WT, Chiang CE, Chen CH, Cheng HM. Optimal stroke preventive strategy for patients aged 80 years or older with atrial fibrillation: a systematic review with traditional and network meta-analysis. Age Ageing 2022; 51:6931851. [PMID: 36571776 DOI: 10.1093/ageing/afac292] [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: 07/28/2022] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND An optimal antithrombotic strategy for patients aged 80 years or older with atrial fibrillation (AF) remains elusive. OBJECTIVE Using a systematic review with traditional and network meta-analysis, we investigated outcomes in AF patients ≥80 years treated with different antithrombotic strategies. METHODS We searched eligible randomised controlled trials (RCTs) and observational studies from MEDLINE, EMBASE, Cochrane Library and Web of Science databases from inception to 16 December 2021. Research comparing treatment outcomes of novel oral anticoagulants (NOACs), aspirin, vitamin K antagonists (VKAs) or no oral anticoagulant/placebo therapy in patients ≥80 years with AF were included. Outcomes were stroke or systemic embolism (SSE), major bleeding, all-cause mortality, intracranial bleeding (ICH) and gastrointestinal bleeding. Traditional and network meta-analyses were performed. Net clinical benefit integrating SSE and major bleeding was calculated. RESULTS Fifty-three studies were identified for analysis. In the meta-analysis of RCTs, risk of SSE (risk ratio [RR]: 0.82; 95% confidence interval [CI]: 0.73-0.99) and ICH (RR: 0.38; 95% CI: 0.28-0.52) was significantly reduced when NOACs were compared with VKAs. Network meta-analysis of RCTs demonstrated that edoxaban (P-score: 0.8976) and apixaban (P-score: 0.8528) outperformed other antithrombotic therapies by showing a lower major bleeding risk and better net clinical benefit. Both traditional and network meta-analyses from RCTs combining with observational studies showed consistent results. CONCLUSIONS In patients aged 80 years or older with AF, NOACs have better outcomes than VKAs regarding efficacy and safety profiles. Edoxaban and apixaban may be preferred treatment options since they are safer than other antithrombotic strategies.
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Affiliation(s)
- Kun-Han Lee
- Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Ying-Fan Chen
- Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Wan-Yu Yeh
- Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan.,Division of Evidence-based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jiunn-Tyng Yeh
- Department of Internal Medicine, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan
| | - Tzu-Han Yang
- Department of Pharmacy, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chian-Ying Chou
- Department of Pharmacy, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yuh-Lih Chang
- Department of Pharmacy, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Department and Institute of Pharmacology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Wei-Ting Wang
- Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chern-En Chiang
- School of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan.,General Clinical Research Center, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chen-Huan Chen
- Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan.,Institute of Public Health, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan
| | - Hao-Min Cheng
- Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan.,Division of Evidence-based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan.,Institute of Public Health, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan
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Fang X, Yeh JT, Hwang TC. Pharmacological Responses of the G542X-CFTR to CFTR Modulators. Front Mol Biosci 2022; 9:921680. [PMID: 35813815 PMCID: PMC9263564 DOI: 10.3389/fmolb.2022.921680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
Cystic fibrosis (CF) is a lethal hereditary disease caused by loss-of-function mutations of the chloride channel cystic fibrosis transmembrane conductance regulator (CFTR). With the development of small-molecule CFTR modulators, including correctors that facilitate protein folding and expression and potentiators that promote channel activity, about 90% of the CF patients are now receiving efficacious target therapies. G542X-CFTR, a premature termination codon (PTC) mutation, is the most common disease-associated mutation found in the remaining 10% of patients that await effective drugs to rectify the fundamental defects caused by PTC. In this study, we employed biophysical and biochemical techniques to characterize the pharmacological responses of the translational products of G542X-CFTR to a range of new CFTR modulators. Specifically, we identified two different proteins translated from the G542X-CFTR cDNA using western blotting: the C-terminus truncated protein that responds to the C1 corrector which binds to the N-terminal part of the protein and a full-length CFTR protein through the read-through process. Electrophysiological data suggest that the read-through protein, but not the C-terminus truncated one, is functional and responds well to CFTR potentiators despite a lower open probability compared to wild-type CFTR. As the expression of the read-through products can be increased synergistically with the read-through reagent G418 and C1 corrector, but not with combinations of different types of correctors, we concluded that an efficacious read-through reagent is a prerequisite for mitigating the deficits of G542X-CFTR. Moreover, the CFTR potentiators may help improve the effectiveness of future combinational therapy for patients carrying PTCs such as G542X.
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Affiliation(s)
- Xinxiu Fang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, United States
| | - Jiunn-Tyng Yeh
- School of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
- *Correspondence: Jiunn-Tyng Yeh,
| | - Tzyh-Chang Hwang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, United States
- Department of Pharmacology, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
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Yeh JT, Shulruf B, Lee HC, Huang PH, Kuo WH, Hwang TC, Chen CH. Faculty appointment and promotion in Taiwan's medical schools, a systematic analysis. BMC Med Educ 2022; 22:356. [PMID: 35538519 PMCID: PMC9088140 DOI: 10.1186/s12909-022-03435-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 05/05/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND A rigorous faculty appointment and promotion (FAP) system is vital for the success of any academic institution. However, studies examining the FAP system in Asian universities are lacking. We surveyed the FAP policies of Taiwan's medical schools and identified an overreliance on the CJA score (manuscript Category, Journal quality, and Author order). The potential shortcomings of this metric and recommendations for refinement were discussed. METHODS We obtained the FAP documents from all 12 medical schools in Taiwan, and analyzed their use of traditional versus non-traditional criteria for FAP according to a published methodology. The influence of the journal impact factor (JIF) on the FAP process was quantified by comparing its relative weight between papers with two extreme JIFs. To better understand the research impact and international standing of each school, we utilized the public bibliographic database to rank universities by the number of papers, and the proportions of papers within the top 10% or 50% citation. RESULTS Compared with other countries, Taiwan's medical schools focus more on the quantifiable quality of the research, mostly using a "CJA" score that integrates the category, JIF or ranking, and authorship of a paper, with the JIF being the most influential factor. The CJA score for an article with a JIF of 20 can be up to three times the threshold for promotion to Assistant Professor. The emphasis on JIF is based on a presumed correlation between JIF and citation counts. However, our analysis shows that Taiwan's medical schools have lower-than-average citation counts despite a competitive rank in the number of publications. CONCLUSIONS The JIF plays an unrivaled role in determining the outcome of FAP in Taiwan's medical schools, mostly via the CJA system. The questionable effectiveness of the current system in elevating the international standing of Taiwan's higher-education institutions calls for a re-examination of the FAP system. We recommend a reduction in the relative importance of CJA score in the FAP system, adopting more rigorous metrics such as the h-index for evaluating research quality, and supporting more research aimed at improving the FAP system.
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Affiliation(s)
- Jiunn-Tyng Yeh
- Department of Medicine, Yang Ming Campus, National Yang Ming Chiao Tung University College of Medicine, 155 Li-Long St., Sec. 2, Shih-Pai, Taipei, 112, Taiwan R.O.C
| | - Boaz Shulruf
- Office of Medical Education, University of New South Wales, Sydney, Australia
| | - Hsin-Chen Lee
- Institute of Pharmacology, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
| | - Pin-Hsiang Huang
- Office of Medical Education, University of New South Wales, Sydney, Australia
- Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Wen-Hua Kuo
- Institute of Science, Technology and Society, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Institute of Public Health, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
| | - Tyzh-Chang Hwang
- Institute of Pharmacology, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
| | - Chen-Huan Chen
- Department of Medicine, Yang Ming Campus, National Yang Ming Chiao Tung University College of Medicine, 155 Li-Long St., Sec. 2, Shih-Pai, Taipei, 112, Taiwan R.O.C..
- Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan.
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Khor W, Hwang TC, Wang CC, Yarmishyn AA, Yeh JT, Chiou SH, Chou SJ. Generation of Human Induced Pluripotent Stem Cells from Cystic Fibrosis Patient Carrying Nonsense Mutation (p.S308X) in CFTR Gene. Stem Cell Res 2022; 60:102683. [DOI: 10.1016/j.scr.2022.102683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 11/26/2022] Open
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Yeh JT, Chiu TJ, Cheng HM. Reply to "Letter to the Editor for the Review Paper: The association between blood pressure variability with dementia and cognitive function: A systematic review and meta-analysis". J Clin Hypertens (Greenwich) 2021; 24:89-90. [PMID: 34894174 PMCID: PMC8783330 DOI: 10.1111/jch.14410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Jiunn-Tyng Yeh
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
| | - Tzu-Jung Chiu
- Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Hao-Min Cheng
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan.,Center for Evidence-based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Public Health, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,Institute of Health and Welfare Policy, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
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7
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Chiu TJ, Yeh JT, Huang CJ, Chiang CE, Sung SH, Chen CH, Cheng HM. Blood pressure variability and cognitive dysfunction: A systematic review and meta-analysis of longitudinal cohort studies. J Clin Hypertens (Greenwich) 2021; 23:1463-1482. [PMID: 34153171 PMCID: PMC8678719 DOI: 10.1111/jch.14310] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 04/21/2021] [Revised: 05/22/2021] [Accepted: 05/29/2021] [Indexed: 01/13/2023]
Abstract
The variability of blood pressure (BPV) has been suggested as a clinical indicator for cognitive dysfunction, yet the results from clinical studies are variable. This study investigated the relationship between BPV and the risk of cognitive decline or dementia. Bibliographic databases, including PubMed, Scopus, and Embase, were searched systematically for longitudinal cohort studies with BPV measurements and neuropsychological examinations or dementia diagnosis. A traditional meta‐analysis with subgroup analysis, and a further dose‐response meta‐analysis were conducted. Twenty cohort studies with 7 924 168 persons were included in this review. The results showed that a higher systolic BPV (SBPV), when measured with the coefficient of variation (SBP‐CV) or standard deviation (SBP‐SD), was associated with a higher risk of all‐cause dementia diagnosis but not incidence of cognitive decline on neuropsychological examinations. In subgroup analysis, the effect was more prominent when using BPV of shorter timeframes, during shorter follow‐ups, or among the elderly aged more than 65 years. No dose‐response relationship could be found. Our study suggested possible positive associations between SBPV and the risk of dementia. Further studies are required to validate these findings.
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Affiliation(s)
- Tzu-Jung Chiu
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
| | - Jiunn-Tyng Yeh
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan
| | - Chi-Jung Huang
- Center for Evidence-Based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chern-En Chiang
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,General Clinical Research Center, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Shih-Hsien Sung
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chen-Huan Chen
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,Institute of Public Health and Community Medicine Research Center, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Hao-Min Cheng
- Department of Medicine, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,Center for Evidence-Based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Public Health and Community Medicine Research Center, National Yang Ming Chiao Tung University College of Medicine, Taipei, Taiwan.,Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan
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8
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Silva IAL, Doušová T, Ramalho S, Centeio R, Clarke LA, Railean V, Botelho HM, Holubová A, Valášková I, Yeh JT, Hwang TC, Farinha CM, Kunzelmann K, Amaral MD. Organoids as a personalized medicine tool for ultra-rare mutations in cystic fibrosis: The case of S955P and 1717-2A>G. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165905. [PMID: 32730979 PMCID: PMC7484254 DOI: 10.1016/j.bbadis.2020.165905] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 01/14/2020] [Revised: 07/07/2020] [Accepted: 07/22/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND For most of the >2000 CFTR gene variants reported, neither the associated disease liability nor the underlying basic defect are known, and yet these are essential for disease prognosis and CFTR-based therapeutics. Here we aimed to characterize two ultra-rare mutations - 1717-2A > G (c.1585-2A > G) and S955P (p.Ser955Pro) - as case studies for personalized medicine. METHODS Patient-derived rectal biopsies and intestinal organoids from two individuals with each of these mutations and F508del (p.Phe508del) in the other allele were used to assess CFTR function, response to modulators and RNA splicing pattern. In parallel, we used cellular models to further characterize S955P independently of F508del and to assess its response to CFTR modulators. RESULTS Results in both rectal biopsies and intestinal organoids from both patients evidence residual CFTR function. Further characterization shows that 1717-2A > G leads to alternative splicing generating <1% normal CFTR mRNA and that S955P affects CFTR gating. Finally, studies in organoids predict that both patients are responders to VX-770 alone and even more to VX-770 combined with VX-809 or VX-661, although to different levels. CONCLUSION This study demonstrates the high potential of personalized medicine through theranostics to extend the label of approved drugs to patients with rare mutations.
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Affiliation(s)
- Iris A L Silva
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal
| | - Tereza Doušová
- Department of Pediatrics, 2nd Faculty of Medicine, Charles University and University Hospital Motol, V Uvalu 84,Prague 5, 150 06 Prague, Czech Republic
| | - Sofia Ramalho
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal
| | - Raquel Centeio
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal
| | - Luka A Clarke
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal
| | - Violeta Railean
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal
| | - Hugo M Botelho
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal
| | - Andrea Holubová
- Department of Biology and Medical Genetics, 2nd Faculty of Medicine, Charles University and University Hospital Motol, V Uvalu 84,Prague 5, 150 06 Prague, Czech Republic
| | - Iveta Valášková
- Department of Medical Genetics, Masaryk University Brno and University Hospital Brno, Jihlavská 20, Brno 625 00, Czech Republic
| | - Jiunn-Tyng Yeh
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, United States of America
| | - Tzyh-Chang Hwang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, United States of America
| | - Carlos M Farinha
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal
| | - Karl Kunzelmann
- Institut für Physiologie, Universität Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Margarida D Amaral
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, C8 bdg, 1749-016 Lisboa, Portugal.
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Yeh JT, Hwang TC. Positional effects of premature termination codons on the biochemical and biophysical properties of CFTR. J Physiol 2019; 598:517-541. [PMID: 31585024 DOI: 10.1113/jp278418] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/16/2019] [Indexed: 12/14/2022] Open
Abstract
KEY POINTS Biochemical and biophysical characterizations of three nonsense mutations of cystic fibrosis transmembrane conductance regulator (CFTR) associated with a severe form of cystic fibrosis (CF) reveal the importance and heterogenous effects of the position of the premature termination codon (PTC) on the CFTR protein function. Electrophysiological studies of W1282X-CFTR, whose PTC is closer to the C-terminus of CFTR, suggest the presence of both C-terminus truncated CFTR proteins that are poorly functional and read-through, full-length products. For G542X- and E60X-CFTR, the only mechanism capable of generating functional proteins is the read-through, but the outcome of read-through products is highly variable depending on the interplay between the missense mutation caused by the read-through and the structural context of the protein. Pharmacological studies of these three PTCs with various CFTR modulators suggest position-dependent therapeutic strategies for these disease-inflicting mutations. ABSTRACT About one-third of genetic diseases and cancers are caused by the introduction of premature termination codons (PTCs). In theory, the location of the PTC in a gene determines the alternative mechanisms of translation, including premature cessation or reinitiation of translation, and read-through, resulting in differential effects on protein integrity. In this study, we used CFTR as a model system to investigate the positional effect of the PTC because of its well-understood structure-function relationship and pathophysiology. The characterization of three PTC mutations, E60X-, G542X- and W1282X-CFTR revealed heterogenous effects of these PTCs on CFTR function. The W1282X mutation results in both C-terminus truncated and read-through proteins that are partially or fully functional. In contrast, only the read-through protein is functional with E60X- and G542X-CFTR, although abundant N-terminus truncated proteins due to reinitiation of translation were detected in E60X-CFTR. Single-channel studies of the read-through proteins of E60X- and G542X-CFTR demonstrated that both mutations have a single-channel amplitude similar to wild type (WT), and good responses to high-affinity ATP analogues, suggesting intact ion permeation pathways and nucleotide binding domains (NBDs), albeit with reduced open probability (Po ). The comparison of the Po of these mutations with the proposed missense mutations revealed potential identities of the read-through products. Importantly, a majority of the functional protein studied responds to CFTR modulators like GLPG1837 and Lumacaftor. These results not only expand current understanding of the molecular (patho)physiology of CFTR, but also infer therapeutic strategies for different PTC mutations at large.
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Affiliation(s)
- Jiunn-Tyng Yeh
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, 65211, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, 65211, USA
| | - Tzyh-Chang Hwang
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, 65211, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Pharmacology and Physiology, School of Medicine, University of Missouri, Columbia, MO, 65211, USA
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10
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Yeh JT, Yu YC, Hwang TC. Structural mechanisms for defective CFTR gating caused by the Q1412X mutation, a severe Class VI pathogenic mutation in cystic fibrosis. J Physiol 2018; 597:543-560. [PMID: 30408177 DOI: 10.1113/jp277042] [Citation(s) in RCA: 7] [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: 09/21/2018] [Accepted: 11/06/2018] [Indexed: 12/14/2022] Open
Abstract
KEY POINTS Electrophysiological characterization of Q1412X-CFTR, a C-terminal truncation mutation of cystic fibrosis transmembrane conductance regulator (CFTR) associated with the severe form of cystic fibrosis (CF), reveals a gating defect that has not been reported previously. Mechanistic investigations of the gating deficit in Q1412X-CFTR suggest that the reduced open probability in Q1412X-CFTR is the result of a disruption of the function of the second ATP binding site (or site 2) in the nucleotide binding domains (NBDs). Detailed comparisons of several mutations with different degrees of truncation in the C-terminal region of NBD2 reveal the importance of the last two beta-strands in NBD2 for maintaining proper gating functions. The results of the present study also show that the application of clinically-approved drugs (VX-770 and VX-809) can greatly enhance the function of Q1412X, providing in vitro evidence for a therapeutic strategy employing both reagents for patients bearing Q1412X or similar truncation mutations. ABSTRACT Cystic fibrosis (CF) is caused by loss-of-function mutations of cystic fibrosis transmembrane conductance regulator (CFTR), a phosphorylation-activated but ATP-gated chloride channel. Based on the molecular mechanism of CF pathogenesis, disease-associated mutations are categorized into six classes. Among them, Class VI, whose members include some of the C-terminal truncation mutations such as Q1412X, is defined as decreased membrane expression because of a faster turnover rate. In the present study, we characterized the functional properties of Q1412X-CFTR, a severe-form premature stop codon mutation. We confirmed previous findings of a ∼90% decrease in membrane expression but found a ∼95% reduction in the open probability (Po ). Detailed kinetic studies support the idea that the gating defect is the result of a dysfunctional ATP-binding site 2 in the nucleotide binding domains (NBDs). Because the Q1412X mutation results in a deletion of the last two beta-strands in NBD2 and the whole C-terminal region, we further characterized truncation mutations with different degrees of deletion in this segment. Mutations that completely or partially remove the C-terminus of CFTR at the same time as keeping an intact NBD2 (i.e. D1425X and S1455X) assume gating function almost identical to that of wild-type channels. However, the deletion of the last beta-strand in the NBD2 (i.e. N1419X) causes gating dysfunction that is milder than that of Q1412X. Thus, normal CFTR gating requires structural integrity of NBD2. Moreover, our observation that clinically-approved VX-809 (Lumacaftor, Vertex Pharmaceuticals, Boston, MA, USA) and VX-770 (Ivacaftor, Vertex Pharmaceuticals, Boston, MA, USA) significantly enhance the overall function of Q1412X-CFTR provides the conceptual basis for the treatment of patients carrying this mutation.
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Affiliation(s)
- Jiunn-Tyng Yeh
- Interdisciplinary Neuroscience Program.,Dalton Cardiovascular Research Center
| | - Ying-Chun Yu
- Dalton Cardiovascular Research Center.,Department of Pharmacology and Physiology, School of Medicine, University of Missouri-Columbia, MO, USA
| | - Tzyh-Chang Hwang
- Interdisciplinary Neuroscience Program.,Dalton Cardiovascular Research Center.,Department of Pharmacology and Physiology, School of Medicine, University of Missouri-Columbia, MO, USA
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Hwang TC, Yeh JT, Zhang J, Yu YC, Yeh HI, Destefano S. Structural mechanisms of CFTR function and dysfunction. J Gen Physiol 2018; 150:539-570. [PMID: 29581173 PMCID: PMC5881446 DOI: 10.1085/jgp.201711946] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [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: 11/16/2017] [Accepted: 03/05/2018] [Indexed: 12/18/2022] Open
Abstract
Hwang et al. integrate new structural insights with prior functional studies to reveal the functional anatomy of CFTR chloride channels. Cystic fibrosis (CF) transmembrane conductance regulator (CFTR) chloride channel plays a critical role in regulating transepithelial movement of water and electrolyte in exocrine tissues. Malfunction of the channel because of mutations of the cftr gene results in CF, the most prevalent lethal genetic disease among Caucasians. Recently, the publication of atomic structures of CFTR in two distinct conformations provides, for the first time, a clear overview of the protein. However, given the highly dynamic nature of the interactions among CFTR’s various domains, better understanding of the functional significance of these structures requires an integration of these new structural insights with previously established biochemical/biophysical studies, which is the goal of this review.
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Affiliation(s)
- Tzyh-Chang Hwang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO .,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO.,Department of Biological Engineering, University of Missouri, Columbia, MO
| | - Jiunn-Tyng Yeh
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO
| | - Jingyao Zhang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO.,Department of Biological Engineering, University of Missouri, Columbia, MO
| | - Ying-Chun Yu
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
| | - Han-I Yeh
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
| | - Samantha Destefano
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
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Yeh HI, Yeh JT, Hwang TC. Potentiation of CFTR Gating by an Energetically Additive Mechanism. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) is unique among ion channels in that after its phosphorylation by protein kinase A (PKA), its ATP-dependent gating violates microscopic reversibility caused by the intimate involvement of ATP hydrolysis in controlling channel closure. Recent studies suggest a gating model featuring an energetic coupling between opening and closing of the gate in CFTR's transmembrane domains and association and dissociation of its two nucleotide-binding domains (NBDs). We found that permeant ions such as nitrate can increase the open probability (Po) of wild-type (WT) CFTR by increasing the opening rate and decreasing the closing rate. Nearly identical effects were seen with a construct in which activity does not require phosphorylation of the regulatory domain, indicating that nitrate primarily affects ATP-dependent gating steps rather than PKA-dependent phosphorylation. Surprisingly, the effects of nitrate on CFTR gating are remarkably similar to those of VX-770 (N-(2,4-Di-tert-butyl-5-hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxamide), a potent CFTR potentiator used in clinics. These include effects on single-channel kinetics of WT CFTR, deceleration of the nonhydrolytic closing rate, and potentiation of the Po of the disease-associated mutant G551D. In addition, both VX-770 and nitrate increased the activity of a CFTR construct lacking NBD2 (ΔNBD2), indicating that these gating effects are independent of NBD dimerization. Nonetheless, whereas VX-770 is equally effective when applied from either side of the membrane, nitrate potentiates gating mainly from the cytoplasmic side, implicating a common mechanism for gating modulation mediated through two separate sites of action.
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Affiliation(s)
- Han-I Yeh
- Physician-Scientist Program, School of Medicine, National Yang-Ming University, Taipei, 112 Taiwan Dalton Cardiovascular Research Center and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211
| | - Jiunn-Tyng Yeh
- Physician-Scientist Program, School of Medicine, National Yang-Ming University, Taipei, 112 Taiwan Dalton Cardiovascular Research Center and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211
| | - Tzyh-Chang Hwang
- Dalton Cardiovascular Research Center and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211 Dalton Cardiovascular Research Center and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211
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Yeh JT, Yeh HI, Hwang TC. Non-Equilibrium Gating of CFTR Revealed by Nitrate as Charge Carriers. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Lin DZ, Chen YP, Jhuang PJ, Chu JY, Yeh JT, Wang JK. Optimizing electromagnetic enhancement of flexible nano-imprinted hexagonally patterned surface-enhanced Raman scattering substrates. Opt Express 2011; 19:4337-4345. [PMID: 21369264 DOI: 10.1364/oe.19.004337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The production of inexpensive, large-scale, uniform substrates for surface-enhanced Raman scattering (SERS) is a key to popularize its usage in chemical and biological detection. We demonstrate a flexible nano-imprinted hexagonally patterned SERS-active substrate. Its electromagnetic enhancement factor was optimized by the thickness adjustment of its silver over-coated film. The experimental data show a good correspondence with the theoretical prediction. Such substrate was shown to exhibit high uniformity and reproducibility with a variation of less than 2%, offering a potential of greatly exploiting such substrate in infield biocide monitoring.
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Affiliation(s)
- D Z Lin
- Material and Chemical Laboratory, Industrial Technology Research Institute, Hsinchu, Taiwan, China.
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Abstract
In our study, we spun a negative photoresist layer on top of a plasmonic lens which was formed by adopting a metallic ring structure with a nano-scale width opening. We recorded the beam shape of the Bessel-like beam emitting from the plasmonic lens which formed a high aspect ratio structure. We found that the high aspect ratio structure was higher after exposure as the inner and outer diameter had increased. In addition, we used an oblique incidence on the negative resist metallic ring structure to produce an inclined micro-structure. Different exposure results were obtained with the two different metal thicknesses. Therefore, in our study, we not only proved that it is possible to record the shape of a Bessel-like beam, but we also demonstrated that it is possible to create a plasmonic lens which is capable of creating a high aspect ratio structure through exposure.
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Affiliation(s)
- C K Chang
- Institute of Applied Mechanics, National Taiwan University, Taipei Taiwan
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Chang YC, Chu JY, Wang TJ, Lin MW, Yeh JT, Wang JK. Fourier analysis of surface plasmon waves launched from single nanohole and nanohole arrays: unraveling tip-induced effects. Opt Express 2008; 16:740-747. [PMID: 18542150 DOI: 10.1364/oe.16.000740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The authors report the investigation of surface plasmon waves (SPW) generated by single nanohole and nanohole arrays. Scattering-type scanning near-field microscopy is used to directly observe near-field distribution. The images after Fourier transformation display characteristic patterns that match with the derived analytic formula. The correspondence helps to identify the role of the scanning tip in generating SPW, making possible of the removal of this tip-induced effect. This study provides a means to perform in-depth investigation on surface plasmon polaritons.
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Affiliation(s)
- Y C Chang
- Material Research Laboratory, Industrial Technology Research Institute, Hsinchu 31040, Taiwan, ROC.
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Chang CK, Lin DZ, Chang YC, Lin MW, Yeh JT, Liu JM, Yeh CS, Lee CK. Enhancing intensity of emitted light from a ring by incorporating a circular groove. Opt Express 2007; 15:15029-15034. [PMID: 19550784 DOI: 10.1364/oe.15.015029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We fabricated a ring containing a single circular groove (RCG) on silver film and which was supported on a glass substrate. We found that by changing the mean radius of the circular groove, the light intensity emitted from the RCG can be modulated by using the scattering light from the circular groove. In addition, we also fabricated circular grooves with the same depth but of different widths so that we could examine the scattering light behavior of the grooves. Herein, we propose a theoretical model which takes into account the amplitude modulation of the cylindrical waves. Our results showed that our proposed model agreed well with the experimental results.
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Chang CK, Lin DZ, Yeh CS, Lee CK, Chang YC, Lin MW, Yeh JT, Liu JM. Similarities and differences for light-induced surface plasmons in one- and two-dimensional symmetrical metallic nanostructures. Opt Lett 2006; 31:2341-3. [PMID: 16832479 DOI: 10.1364/ol.31.002341] [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] [Indexed: 05/10/2023]
Abstract
Two types of double-sided nanostructure, one possessing a slit aperture with parallel grooves and the other possessing a circular aperture with concentric grooves, were fabricated to examine the similarities and differences of their diffraction behavior in one-dimensional (1-D) and two-dimensional (2-D) nanostructures. Based on the projection-slice theory, we conjecture that the surface plasmons in these two different nano-scale grooves possess similar modes. A localized surface plasmon (LSP) was used to examine the transmission characteristics induced by the apertures. The transmission characteristics of the slitted nanostructure and the circular nanostructure aperture were then measured. We coupled the transmission spectra measured from these two apertures with a 1-D parallel groove transmission curve simulated by a 1-D rigorous coupled wave analysis. Measured spectra results show reasonable agreement with the simulated data. We propose that the apparent blueshift observed in the peak frequency of a 2-D nanostructure is due to the difference in the shape of the aperture and the spot transmission characteristics of 1-D and 2-D systems as induced by a LSP.
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Affiliation(s)
- C K Chang
- Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan
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Lin DZ, Chang CK, Chen YC, Yang DL, Lin MW, Yeh JT, Liu JM, Kuan CH, Yeh CS, Lee CK. Beaming light from a subwavelength metal slit surrounded by dielectric surface gratings. Opt Express 2006; 14:3503-3511. [PMID: 19516497 DOI: 10.1364/oe.14.003503] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this article, we demonstrate that a subwavelength metal slit surrounded by dielectric surface gratings possesses a directional beaming effect. We propose a surface plasmon diffraction scheme to explain the three kinds of beaming conditions. The numerical simulations of the illustrative structures undertaken used a Finite Difference Time Domain (FDTD) Method and a Rigorous Coupled Wave Analysis (RCWA) Method. Our simulations were found to be consistent and in agreement with the experimental results. In comparison with other metal structures, we find that dielectric metal structures offer better performance as well as the advantage of being able to be efficiently mass produced for large volume industrial applications.
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Affiliation(s)
- J T Yeh
- Department of Surgery, Chang Gung Memorial Hospital, Chang Gung Medical College, Taipei, Taiwan
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Yeh JT, Lai HS, Duh YC. Perforated Meckel's diverticulum in a neonate. J Formos Med Assoc 1996; 95:644-5. [PMID: 8870439] [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: 02/02/2023] Open
Abstract
A case of Meckel's diverticulum is reported in an eight-day-old male baby, the youngest patient to have had this condition at National Taiwan University Hospital. The baby had been affected by bilious vomiting of 3 days' duration and abdominal distension before being brought to the hospital. A perforated Meckel's diverticulum was found during emergency laparotomy. The resected Meckel's diverticulum did not contain ectopic tissue. The narrow lumen and narrow base of the diverticulum was thought to be the cause of poor self-emptying and subsequent acute inflammation and perforation.
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Affiliation(s)
- J T Yeh
- Department of Surgery, National Taiwan University Hospital, Taipei, ROC
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Matsui K, Sawasaki T, Yeh JT, Mori Y, Mochimaru H, Nakao K, Nagai Y, Kano Y. [Rearing trial of a feed for Shiba goats]. Jikken Dobutsu 1981; 30:35-9. [PMID: 7262200 DOI: 10.1538/expanim1978.30.1_35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Shiba goats are among the widely used for research purposes as laboratory animals and there is an increasing need for development of a suitable feed of reasonably constant nutrient composition and quality in pellet form for them. Preliminary studies yielded a pellet feed satisfactorily palatable and adequate as a maintenance ration for this species. The present experiments were conducted to assess the pellet feed for usefulness in rearing Shiba goats, in comparison with a conventional ration which has long been used at the Stock Farm of Tokyo University. No significant intergroup differences were observed as to VFA proportions in the rumen fluid, hematologic parameters or blood chemical constituents between the pellet feed and conventional ration. Animals maintained on the experimental pellets ad libitum displayed a significant decrease in apparent digestibility.
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