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Lin L, Kwan CT, Yap PM, Fung SY, Tang HS, Tse WWV, Kwan CNF, Chow YHP, Yiu NC, Lee YP, Fong AHT, Ren QW, Wu MZ, Lee KCK, Leung CY, Li A, Montero D, Vardhanabhuti V, Hai J, Siu CW, Tse H, Pennell DJ, Mohiaddin R, Senior R, Yiu KH, Ng MY. Diagnostic Performance of Cardiovascular Magnetic Resonance Phase Contrast Analysis to Identify Heart Failure With Preserved Ejection Fraction. J Thorac Imaging 2024:00005382-990000000-00126. [PMID: 38465896 DOI: 10.1097/rti.0000000000000777] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Affiliation(s)
- Lu Lin
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
- Department of Diagnostic Radiology, School of Clinical Medicine
| | - Chi Ting Kwan
- Department of Diagnostic Radiology, School of Clinical Medicine
| | - Pui Min Yap
- Department of Diagnostic Radiology, School of Clinical Medicine
| | - Sau Yung Fung
- Department of Diagnostic Radiology, School of Clinical Medicine
| | - Hok Shing Tang
- Department of Diagnostic Radiology, School of Clinical Medicine
| | | | | | | | - Nga Ching Yiu
- Department of Diagnostic Radiology, School of Clinical Medicine
| | - Yung Pok Lee
- Department of Diagnostic Radiology, School of Clinical Medicine
| | | | - Qing-Wen Ren
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital
| | - Mei-Zhen Wu
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital
| | - Ka Chun Kevin Lee
- Department of Medicine and Geriatrics, Ruttonjee and Tang Shiu Kin Hospitals, Wan Chai
| | - Chun Yu Leung
- Department of Medicine, Tseung Kwan O Hospital, Tseung Kwan O
| | - Andrew Li
- Department of Medicine and Therapeutics, United Christian Hospital, Kwun Tong
| | - David Montero
- School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Patrick Manson Building (North Wing), Pokfulam, Hong Kong SAR, China
| | - Varut Vardhanabhuti
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital
| | - JoJo Hai
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital
| | - Chung-Wah Siu
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital
| | - HungFat Tse
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital
| | - Dudley John Pennell
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street
- National Heart and Lung Institute, Imperial College, Guy Scadding Building, Cale Street, London
| | - Raad Mohiaddin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street
- National Heart and Lung Institute, Imperial College, Guy Scadding Building, Cale Street, London
| | - Roxy Senior
- National Heart and Lung Institute, Imperial College, Guy Scadding Building, Cale Street, London
- Department of Cardiology, Northwick Park Hospital, Harrow
- Department of Cardiology, Royal Brompton Hospital, Sydney Street, London, UK
| | - Kai-Hang Yiu
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital
| | - Ming-Yen Ng
- Department of Diagnostic Radiology, School of Clinical Medicine
- Department of Medical Imaging, The University of Hong Kong-Shenzhen Hospital, Futian, Shenzhen, Guangdong, China
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Ng MY, Tam CH, Lee YP, Fong HTA, Wong CK, Ng WKC, Yeung MHY, Ling WHI, Tsao S, Wan EYF, Ferreira V, Yan AT, Siu CW, Yiu KH, Hung IFN. Post-COVID-19 vaccination myocarditis: a prospective cohort study pre and post vaccination using cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2023; 25:74. [PMID: 38057820 PMCID: PMC10702006 DOI: 10.1186/s12968-023-00985-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/12/2023] [Indexed: 12/08/2023] Open
Abstract
BACKGROUND Concerns about COVID-19 vaccination induced myocarditis or subclinical myocarditis persists in some populations. Cardiac magnetic resonance imaging (CMR) has been used to detect signs of COVID-19 vaccination induced myocarditis. This study aims to: (i) characterise myocardial tissue, function, size before and after COVID-19 vaccination, (ii) determine if there is imaging evidence of subclinical myocardial inflammation or injury after vaccination using CMR. METHODS Subjects aged ≥ 12yrs old without prior COVID-19 or COVID-19 vaccination underwent two CMR examinations: first, ≤ 14 days before the first COVID-19 vaccination and a second time ≤ 14 days after the second COVID-19 vaccination. Biventricular indices, ejection fraction (EF), global longitudinal strain (GLS), late gadolinium enhancement (LGE), left ventricular (LV) myocardial native T1, T2, extracellular volume (ECV) quantification, lactate dehydrogenase (LDH), white cell count (WCC), C-reactive protein (CRP), NT-proBNP, troponin-T, electrocardiogram (ECG), and 6-min walk test were assessed in a blinded fashion. RESULTS 67 subjects were included. First and second CMR examinations were performed a median of 4 days before the first vaccination (interquartile range 1-8 days) and 5 days (interquartile range 3-6 days) after the second vaccination respectively. No significant change in global native T1, T2, ECV, LV EF, right ventricular EF, LV GLS, LGE, ECG, LDH, troponin-T and 6-min walk test was demonstrated after COVID-19 vaccination. There was a significant WCC decrease (6.51 ± 1.49 vs 5.98 ± 1.65, p = 0.003) and CRP increase (0.40 ± 0.22 vs 0.50 ± 0.29, p = 0.004). CONCLUSION This study found no imaging, biochemical or ECG evidence of myocardial injury or inflammation post COVID-19 vaccination, thus providing some reassurance that COVID-19 vaccinations do not typically cause subclinical myocarditis.
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Affiliation(s)
- Ming-Yen Ng
- Department of Diagnostic Radiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Room 406, Block K, Queen Mary Hospital, Hong Kong SAR, China.
- Department of Medical Imaging, HKU-Shenzhen Hospital, Shenzhen, China.
| | - Cheuk Hang Tam
- Department of Diagnostic Radiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Room 406, Block K, Queen Mary Hospital, Hong Kong SAR, China
| | - Yung Pok Lee
- Department of Diagnostic Radiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Room 406, Block K, Queen Mary Hospital, Hong Kong SAR, China
| | - Ho Tung Ambrose Fong
- Department of Diagnostic Radiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Room 406, Block K, Queen Mary Hospital, Hong Kong SAR, China
| | - Chun-Ka Wong
- Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
| | - Wing Kei Carol Ng
- Department of Radiology, Hong Kong Children's Hospital, Hong Kong SAR, China
| | - Maegan Hon Yan Yeung
- Department of Diagnostic Radiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Room 406, Block K, Queen Mary Hospital, Hong Kong SAR, China
| | - Wood-Hay Ian Ling
- Grantham Hospital, 125 Wong Chuk Hang Rd, Aberdeen, Hong Kong SAR, China
| | - Sabrina Tsao
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Eric Yuk Fai Wan
- Department of Family Medicine and Primary Care, The University of Hong Kong, Hong Kong SAR, China
- Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong SAR, China
| | - Vanessa Ferreira
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford BHF Centre of Research Excellence, Oxford Centre for Clinical Magnetic Resonance Research, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Andrew T Yan
- St. Michael's Hospital, University of Toronto, Toronto, Canada
| | - Chung Wah Siu
- Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
| | - Kai-Hang Yiu
- Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
| | - Ivan Fan-Ngai Hung
- Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
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Kwan CT, Ching OHS, Yap PM, Fung SY, Tang HS, Tse WWV, Kwan CNF, Chow YHP, Yiu NC, Lee YP, Lau JWK, Fong AHT, Ren QW, Wu MZ, Wan EYF, Lee KCK, Leung CY, Li A, Montero D, Vardhanabhuti V, Hai JSH, Siu CW, Tse HF, Zingan V, Zhao X, Wang H, Pennell DJ, Mohiaddin R, Senior R, Yiu KH, Ng MY. Intraventricular 4D flow cardiovascular magnetic resonance for assessing patients with heart failure with preserved ejection fraction: a pilot study. Int J Cardiovasc Imaging 2023; 39:2015-2027. [PMID: 37380904 DOI: 10.1007/s10554-023-02909-8] [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] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 06/22/2023] [Indexed: 06/30/2023]
Abstract
Diagnosing heart failure with preserved ejection fraction (HFpEF) remains challenging. Intraventricular four-dimensional flow (4D flow) phase-contrast cardiovascular magnetic resonance (CMR) can assess different components of left ventricular (LV) flow including direct flow, delayed ejection, retained inflow and residual volume. This could be utilised to identify HFpEF. This study investigated if intraventricular 4D flow CMR could differentiate HFpEF patients from non-HFpEF and asymptomatic controls. Suspected HFpEF patients and asymptomatic controls were recruited prospectively. HFpEF patients were confirmed using European Society of Cardiology (ESC) 2021 expert recommendations. Non-HFpEF patients were diagnosed if suspected HFpEF patients did not fulfil ESC 2021 criteria. LV direct flow, delayed ejection, retained inflow and residual volume were obtained from 4D flow CMR images. Receiver operating characteristic (ROC) curves were plotted. 63 subjects (25 HFpEF patients, 22 non-HFpEF patients and 16 asymptomatic controls) were included in this study. 46% were male, mean age 69.8 ± 9.1 years. CMR 4D flow derived LV direct flow and residual volume could differentiate HFpEF vs combined group of non-HFpEF and asymptomatic controls (p < 0.001 for both) as well as HFpEF vs non-HFpEF patients (p = 0.021 and p = 0.005, respectively). Among the 4 parameters, direct flow had the largest area under curve (AUC) of 0.781 when comparing HFpEF vs combined group of non-HFpEF and asymptomatic controls, while residual volume had the largest AUC of 0.740 when comparing HFpEF and non-HFpEF patients. CMR 4D flow derived LV direct flow and residual volume show promise in differentiating HFpEF patients from non-HFpEF patients.
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Affiliation(s)
- Chi Ting Kwan
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - On Hang Samuel Ching
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Pui Min Yap
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Sau Yung Fung
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Hok Shing Tang
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Wan Wai Vivian Tse
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Cheuk Nam Felix Kwan
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Yin Hay Phoebe Chow
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Nga Ching Yiu
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Yung Pok Lee
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Jessica Wing Ka Lau
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Ambrose Ho Tung Fong
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Qing-Wen Ren
- Division of Cardiology, Department of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Mei-Zhen Wu
- Division of Cardiology, Department of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Eric Yuk Fai Wan
- Department of Family Medicine and Primary Care, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Ka Chun Kevin Lee
- Department of Medicine and Geriatrics, Ruttonjee and Tang Shiu Kin Hospitals, Wan Chai, Hong Kong
| | - Chun Yu Leung
- Department of Medicine, Tseung Kwan O Hospital, Hong Hau, Hong Kong
| | - Andrew Li
- Department of Medicine and Therapeutics, Chinese University of Hong Kong, New Territories, Hong Kong
| | - David Montero
- School of Public Health, Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Varut Vardhanabhuti
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Jojo Siu Han Hai
- Division of Cardiology, Department of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Chung-Wah Siu
- Division of Cardiology, Department of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Hung-Fat Tse
- Division of Cardiology, Department of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | | | - Xiaoxi Zhao
- Circle Cardiovascular Imaging Inc, Calgary, Canada
| | | | - Dudley John Pennell
- Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Raad Mohiaddin
- Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Roxy Senior
- Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Kai-Hang Yiu
- Division of Cardiology, Department of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Ming-Yen Ng
- Department of Diagnostic Radiology, The University of Hong Kong, Pok Fu Lam, Hong Kong.
- Department of Medical Imaging, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China.
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Ng MY, Kwan CT, Yap PM, Fung SY, Tang HS, Tse WWV, Kwan CNF, Chow YHP, Yiu NC, Lee YP, Fong AHT, Hwang S, Fong ZFW, Ren QW, Wu MZ, Wan EYF, Lee KCK, Leung CY, Li A, Montero D, Vardhanabhuti V, Hai JSH, Siu CW, Tse HF, Pennell DJ, Mohiaddin R, Senior R, Yiu KH. Diagnostic Accuracy of Cardiovascular Magnetic Resonance Strain Analysis and Atrial Size to Identify Heart Failure with Preserved Ejection Fraction. European Heart Journal Open 2023; 3:oead021. [PMID: 36992915 PMCID: PMC10041670 DOI: 10.1093/ehjopen/oead021] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 02/27/2023] [Accepted: 03/03/2023] [Indexed: 03/09/2023]
Abstract
Abstract
Aims
Heart failure with preserved ejection fraction (HFpEF) continues to be a diagnostic challenge. CMR atrial measurements, feature-tracking (CMR-FT), tagging have long been suggested to diagnose HFpEF and potentially complement echocardiography especially when echocardiography is indeterminate. Data supporting the use of atrial measurements, CMR-FT or tagging is absent. Our aim is to conduct a prospective case-control study assessing the diagnostic accuracy of CMR atrial volume/area, CMR-FT, and tagging to diagnose HFpEF amongst patients suspected of having HFpEF.
Methods & Results
121 suspected HFpEF patients were prospectively recruited from four centres. Patients underwent echocardiography, CMR, NT-proBNP measurements within 24 hours to diagnose HFpEF. Patients without HFpEF diagnosis underwent catheter pressure measurements or stress echocardiography to confirm HFpEF or non-HFpEF. Area under the curve (AUC) were determined by comparing HFpEF with non-HFpEF patients. 53 HFpEF (median age 78yrs, interquartile range 74-82yrs) and 38 non-HFpEF (median age 70yrs, interquartile range 64-76yrs). CMR left atrial (LA) reservoir strain (ResS), LA area indexed (LAAi) and LA volume indexed (LAVi) had the highest diagnostic accuracy (AUCs 0.803, 0.815 and 0.776 respectively).
LA ResS, LAAi and LAVi had significantly better diagnostic accuracy than CMR-FT left ventricle (LV)/right ventricle (RV) parameters and tagging (p < 0.01). Tagging circumferential and radial strain had poor diagnostic accuracy (AUC 0.644 and 0.541 respectively).
Conclusion
CMR LA ResS, LAAi and LAVi have the highest diagnostic accuracy to identify HFpEF patients from non-HFpEF patients amongst clinically suspected HFpEF patients. CMR-FT LV/RV parameters and tagging had low diagnostic accuracy to diagnose HFpEF.
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Affiliation(s)
- Ming-Yen Ng
- Department of Diagnostic Radiology, The University of Hong Kong
| | - Chi Ting Kwan
- Department of Diagnostic Radiology, The University of Hong Kong
| | - Pui Min Yap
- Department of Diagnostic Radiology, The University of Hong Kong
| | - Sau Yung Fung
- Department of Diagnostic Radiology, The University of Hong Kong
| | - Hok Shing Tang
- Department of Diagnostic Radiology, The University of Hong Kong
| | | | | | | | - Nga Ching Yiu
- Department of Diagnostic Radiology, The University of Hong Kong
| | - Yung Pok Lee
- Department of Diagnostic Radiology, The University of Hong Kong
| | | | - Subin Hwang
- Department of Diagnostic Radiology, The University of Hong Kong
| | | | - Qing-Wen Ren
- Department of Medicine, The University of Hong Kong
| | - Mei-Zhen Wu
- Department of Medicine, The University of Hong Kong
| | - Eric Yuk Fai Wan
- Department of Family Medicine and Primary Care, The University of Hong Kong , Hong Kong
| | - Ka Chun Kevin Lee
- Department of Medicine, Ruttonjee Hospital and Tang Shiu Kin Hospitals , Hong Kong
| | - Chun Yu Leung
- Department of Medicine, Tseung Kwan O Hospital , Hong Kong
| | - Andrew Li
- Department of Medicine, United Christian Hospital , Hong Kong
| | - David Montero
- School of Public Health, Faculty of Medicine, The University of Hong Kong , Hong Kong
| | | | | | | | - Hung-Fat Tse
- Department of Medicine, The University of Hong Kong
| | - Dudley John Pennell
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield NHS Foundation Trust , London , United Kingdom
- National Heart and Lung Institute, Imperial College , London , United Kingdom
| | - Raad Mohiaddin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield NHS Foundation Trust , London , United Kingdom
- National Heart and Lung Institute, Imperial College , London , United Kingdom
| | - Roxy Senior
- National Heart and Lung Institute, Imperial College , London , United Kingdom
- Department of Cardiology, Northwick Park Hospital , Harrow , United Kingdom
- Cardiology, Royal Brompton Hospital , London , United Kingdom
| | - Kai-Hang Yiu
- Department of Medicine, The University of Hong Kong
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Lee YP, Chen YC, Hsu YH. GREAT IMMUNOGLOBULIN G4-RELATED LESION MIMICS PYOGENIC GRANULOMA OF GINGIVA: A RARE CASE REPORT. Oral Surg Oral Med Oral Pathol Oral Radiol 2021. [DOI: 10.1016/j.oooo.2021.03.103] [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: 10/21/2022]
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Hwang JS, Kim YJ, Yoo YJ, Kim KW, Rhee JY, Chen LY, Li SR, Guo XW, Lee YP. Tunable quad-band transmission response, based on single-layer metamaterials. Opt Express 2018; 26:31607-31616. [PMID: 30650744 DOI: 10.1364/oe.26.031607] [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] [Received: 09/17/2018] [Accepted: 11/04/2018] [Indexed: 06/09/2023]
Abstract
We investigated the electromagnetically induced transparency (EIT)-like effects in planar metamaterials (MMs) at microwave (GHz) frequencies. The specific MMs that were used in this study consist of cut-wire resonator/ring resonator, which achieved the dual EIT-like effects in a single-layer through the bright- and quasi-dark-mode coupling and the lattice mode coupling. In addition, by varying the distance between the two resonators, the quad-band EIT spectral response in the microwave region was obtained, and the group refractive index at the EIT-like resonance of proposed design reached up to 4,000. This study provides the design approach to the multispectral EIT-like effects and might suggest potential applications in a variety of fields, for example, low-loss slow-light device, multiple switching sensor, and other sensing devices.
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Lin MJ, Chang SC, Lin TY, Cheng YS, Lee YP, Fan YK. Factors Affecting the Incidence of Angel Wing in White Roman Geese: Stocking Density and Genetic Selection. Asian-Australas J Anim Sci 2015; 29:901-7. [PMID: 26954185 PMCID: PMC4852259 DOI: 10.5713/ajas.15.0456] [Citation(s) in RCA: 9] [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: 05/24/2015] [Revised: 07/06/2015] [Accepted: 08/02/2015] [Indexed: 11/27/2022]
Abstract
The present study investigated stocking density and genetic lines, factors that may alter the severity and incidence of angel wing (AW), in White Roman geese. Geese (n = 384) from two genetically selected lines (normal- winged line, NL, and angel-winged line, AL, respectively) and one commercial line (CL) were raised in four pens. Following common commercial practice, low-stocking-density (LD), medium-stocking-density, and high-stocking-density treatments were respectively administered to 24, 32, and 40 geese per pen at 0 to 3 weeks (1.92 m2/pen) and 4 to 6 weeks (13.2 m2/pen) of age and to 24, 30, and 36 geese at 7 to 14 weeks (20.0 m2/pen) of age. The results revealed that stocking density mainly affected body weight gain in geese younger than 4 weeks, and that geese subjected to LD had a high body weight at 2 weeks of age. However, the effect of stocking density on the severity score of AW (SSAW) and incidence of AW (IAW) did not differ significantly among the treatments. Differences were observed among the genetic stocks; that is, SSAW and IAW were significantly higher in AL than in NL and CL. Genetic selection generally aggravates AW, complicating its elimination. To effectively reduce IAW, stocking density, a suspected causal factor, should be lower than that presently applied commercially.
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Affiliation(s)
- M J Lin
- Department of Animal Science, National Chung Hsing University, Taichung 40227, Taiwan.,Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Executive Yuan, Changhua 52149, Taiwan
| | - S C Chang
- Department of Animal Science, National Chung Hsing University, Taichung 40227, Taiwan.,Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Executive Yuan, Changhua 52149, Taiwan
| | - T Y Lin
- Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Executive Yuan, Changhua 52149, Taiwan
| | - Y S Cheng
- Livestock Research Institute, Council of Agriculture, Executive Yuan, Tainan 71246, Taiwan
| | - Y P Lee
- Department of Animal Science, National Chung Hsing University, Taichung 40227, Taiwan
| | - Y K Fan
- Department of Animal Science, National Chung Hsing University, Taichung 40227, Taiwan
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Ying M, Bhatia KSS, Lee YP, Yuen HY, Ahuja AT. Review of ultrasonography of malignant neck nodes: greyscale, Doppler, contrast enhancement and elastography. Cancer Imaging 2014; 13:658-69. [PMID: 24434158 PMCID: PMC3894696 DOI: 10.1102/1470-7330.2013.0056] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [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] [Indexed: 12/16/2022] Open
Abstract
Assessment of neck lymph nodes is essential in patients with head and neck cancers for predicting the patient’s prognosis and selecting the appropriate treatment. Ultrasonography is a useful imaging tool in the assessment of neck lymph nodes. Greyscale ultrasonography assesses the size, distribution, and internal architecture of lymph nodes. Doppler ultrasonography evaluates the intranodal vascular pattern and resistance of lymph nodes. Contrast-enhanced ultrasonography provides information on lymph node parenchymal perfusion. Elastography allows qualitative and quantitative assessment of lymph node stiffness. This article reviews the value of greyscale, Doppler and contrast-enhanced ultrasonography as well as elastography in the assessment of malignant nodes in the neck.
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Affiliation(s)
- M Ying
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - K S S Bhatia
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China
| | - Y P Lee
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China
| | - H Y Yuen
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China
| | - A T Ahuja
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China
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Cho CM, Tong SL, Bhatia KS, Wong KT, Yuen HY, Lee YP, Ahuja AT. Unusual parotid gland lesions: a pictorial review. J Clin Ultrasound 2013; 41:501-508. [PMID: 23744456 DOI: 10.1002/jcu.22054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 10/20/2011] [Revised: 12/10/2012] [Accepted: 03/27/2013] [Indexed: 06/02/2023]
Abstract
This is a pictorial essay of unusual parotid gland lesions that may be encountered in routine clinical practice.
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Affiliation(s)
- C M Cho
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, 30-32 Ngan Shing Street, Shatin, N.T., Hong Kong, China
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Lam TK, Lau HY, Lee YP, Fung SM, Leung WL, Kam KM. Use of the INNO-LIA syphilis score assay in the resolution of discordant positive screening enzyme immunoassay results for the serological diagnosis of syphilis. Int J STD AIDS 2013; 25:52-6. [DOI: 10.1177/0956462413491938] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We studied the use of the INNO-LIA syphilis score assay in the resolution of discordant positive screening results of the Murex ICE Syphilis enzyme immunoassay (EIA) with the confirmatory results of both the Serodia Treponema pallidum particle agglutination (TPPA) and the fluorescent treponemal antibody-absorption (FTA-Abs) assays, for the serological diagnosis of syphilis. This was an observational study on the serum samples received by the Syphilis Laboratory, Hong Kong, during the period from January 2006 to December 2012. A total of 801 serum samples with discordant positive screening EIA results were used. Consensus results of such serum samples were derived from results of the EIA, TPPA and FTA-abs assays. The age range of the individuals was 14 to 104 years (median of 52). There were 369 males and 432 females. Of 378 serum samples, 139 showed agreement among positive results, 23 of 310 showed agreement among indeterminate results and 277 of 465 showed agreement among negative results. The proportions of agreement among positive, indeterminate and negative results were 0.37 (95% CI 0.32–0.42), 0.07 (95% CI 0.05–0.11) and 0.60 (95% CI 0.55–0.64), respectively; kappa 0.55 (95% CI 0.49–0.60). There were 60 serum samples with positive consensus results but negative INNO-LIA syphilis score results and 10 with negative consensus results but positive INNO-LIA syphilis score results. Although the INNO-LIA syphilis score assay can be considered a valid alternative confirmatory test for the serological diagnosis of syphilis, the present study showed that its use in the resolution of discordant positive screening EIA results was moderate. A more extensive characterization of serum samples with discordant reactive screening treponemal test results is necessary.
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Affiliation(s)
- TK Lam
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - HY Lau
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - YP Lee
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - SM Fung
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - WL Leung
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - KM Kam
- Stanley Ho Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Hong Kong
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11
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Pham MH, Berthouly-Salazar C, Tran XH, Chang WH, Crooijmans RPMA, Lin DY, Hoang VT, Lee YP, Tixier-Boichard M, Chen CF. Genetic diversity of Vietnamese domestic chicken populations as decision-making support for conservation strategies. Anim Genet 2013; 44:509-21. [PMID: 23714019 DOI: 10.1111/age.12045] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2013] [Indexed: 11/27/2022]
Abstract
The aims of this study were to assess the genetic diversity of 17 populations of Vietnamese local chickens (VNN) and one Red Jungle Fowl population, together with six chicken populations of Chinese origin (CNO), and to provide priorities supporting the conservation of genetic resources using 20 microsatellites. Consequently, the VNN populations exhibited a higher diversity than did CNO populations in terms of number of alleles but showed a slightly lower observed heterozygosity. The VNN populations showed in total seven private alleles, whereas no CNO private alleles were found. The expected heterozygosity of 0.576 in the VNN populations was higher than the observed heterozygosity of 0.490, leading to heterozygote deficiency within populations. This issue could be partly explained by the Wahlund effect due to fragmentation of several populations between chicken flocks. Molecular analysis of variance showed that most of genetic variation was found within VNN populations. The Bayesian clustering analysis showed that VNN and CNO chickens were separated into two distinct groups with little evidence for gene flow between them. Among the 24 populations, 13 were successfully assigned to their own cluster, whereas the structuring was not clear for the remaining 11 chicken populations. The contributions of 24 populations to the total genetic diversity were mostly consistent across two approaches, taking into account the within- and between-populations genetic diversity and allelic richness. The black H'mong, Lien Minh, Luong Phuong and Red Jungle Fowl were ranked with the highest priorities for conservation according to Caballero and Toro's and Petit's approaches. In conclusion, a national strategy needs to be set up for Vietnamese chicken populations, with three main components: conservation of high-priority breeds, within-breed management with animal exchanges between flocks to avoid Wahlund effect and monitoring of inbreeding rate.
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Affiliation(s)
- M H Pham
- Department of Animal Science, National Chung-Hsing University, Taichung, Taiwan
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12
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Zheng HY, Jin XR, Park JW, Lu YH, Rhee JY, Jang WH, Cheong H, Lee YP. Tunable dual-band perfect absorbers based on extraordinary optical transmission and Fabry-Perot cavity resonance. Opt Express 2012; 20:24002-24009. [PMID: 23188367 DOI: 10.1364/oe.20.024002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Magnetic resonance is considered to be a necessary condition for metamaterial perfect absorbers, and dual-band absorbers can be composed of a pair of metallic layers with anti-parallel surface currents. We designed and fabricated a tunable dual-band perfect absorber based on extraordinary-optical-transmission (EOT) effect and Fabry-Perot cavity resonance. The idea and the mechanism are completely different from the absorber based on the near-field interaction. The important advantage of our structure is that we can switch a single-band absorber to a dual-band absorber by changing the distance between two metallic layers and/or incident angle. The peak originating from the EOT effect becomes significantly narrower, resulting in an increase of the Q-factor from 16.88 to 49. The dual-band absorber can be optimized to be insensitive to the polarization of the incident electromagnetic wave by slightly modifying the absorber structure.
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Affiliation(s)
- H Y Zheng
- Department of Physics and Quantum Photonic Science Research Center, Hanyang University, Seoul 133-791, South Korea
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13
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Chang CS, Chen CF, Berthouly-Salazar C, Chazara O, Lee YP, Chang CM, Chang KH, Bed'Hom B, Tixier-Boichard M. A global analysis of molecular markers and phenotypic traits in local chicken breeds in Taiwan. Anim Genet 2011; 43:172-82. [PMID: 22404353 DOI: 10.1111/j.1365-2052.2011.02226.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular and phenotypic data have been combined to characterize the genetic diversity of six local chicken breeds maintained with a long-term conservation programme. Hua-Tung, Hsin-Yi, Ju-Chi and Quemoy originated from Taiwan, Shek-Ki is from South China, and Nagoya is from Japan. Molecular tools included 24 microsatellite markers, melanocortin 1 receptor (alpha melanocyte stimulating hormone receptor) (MC1R), the LEI0258 marker located within the major histocompatibility complex (MHC), and mitochondrial DNA. Performance was recorded on the same individuals for body weight, panting rate in summer and antibody response (antigens: Newcastle disease virus and sheep red blood cells). A multivariate method previously proposed for taxonomy was used to combine the different data sets. Melanocortin 1 receptor (alpha melanocyte stimulating hormone receptor) and the MCW330 marker contributed the most to the first axis of the multiple coinertia analysis of molecular markers. Melanocortin 1 receptor (alpha melanocyte stimulating hormone receptor) showed evidence of selection, probably related to its effect on feather colour. The MHC exhibited a large diversity, with 16 alleles of the LEI0258 marker. Immune response traits contributed the most to the principal component analysis of phenotypic data. Eight mitochondrial DNA haplotypes related to clades A, B, C and E were distributed across breeds and revealed an important contribution of Indian and European breeds to Ju-Chi, Quemoy and Hsin-Yi. Phenotypic data contributed less than molecular data to the combined analysis, and two markers, LEI0258 and LEI0228, contributed the most. The combined analysis could clearly discriminate all breeds, except Ju-Chi, which was similar to Quemoy for many criteria, except immune response.
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Affiliation(s)
- C S Chang
- Department of Animal Science, National Chung-Hsing University, Taichung 402, Taiwan.
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Cheong KB, Leung KY, Li TKT, Chan HY, Lee YP, Tang MHY. Comparison of inter- and intraobserver agreement and reliability between three different types of placental volume measurement technique (XI VOCAL, VOCAL and multiplanar) and validity in the in-vitro setting. Ultrasound Obstet Gynecol 2010; 36:210-217. [PMID: 20201116 DOI: 10.1002/uog.7609] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVES To compare XI VOCAL (eXtended Imaging Virtual Organ Computer-aided AnaLysis) for three-dimensional (3D) ultrasound volumetry of the placenta and of phantom objects with a rotational method using VOCAL and with the multiplanar method. METHODS We acquired 3D volume datasets from 32 fetuses at 11-14 weeks' gestation. Placental volume was calculated twice by each of two observers using XI VOCAL (with 5, 10, 15 and 20 slices), multiplanar (1-mm interval) and VOCAL (with 12 degrees, 18 degrees and 30 degrees rotation) methods. In addition, validity was assessed using the in-vitro setting with three phantom objects of known volume. RESULTS Both inter- and intraobserver reliabilities were very high for all three methods. There was no systematic bias between any two methods except between XI VOCAL (10 slices) and the multiplanar (1-mm interval) method, with a smaller volume using the former method. The limits of agreement were wide between any two of the three methods. In the in-vitro setting, there was a trend towards less valid measurements with the XI VOCAL technique and fewer slices. With the same number of steps, measurements made with VOCAL (12 degrees and 18 degrees) were more valid than were those made with XI VOCAL (15 and 10 slices, respectively). CONCLUSION XI VOCAL cannot be used interchangeably with VOCAL or multiplanar techniques in measuring placental volume at 11-14 weeks' gestation.
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Affiliation(s)
- K B Cheong
- Department of Obstetrics and Gynaecology, University of Hong Kong, Queen Mary Hospital, Hong Kong, SAR China
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15
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Abstract
A novel modular perceptron network (MPN) and divide-and-conquer learning (DCL) schemes for the design of modular neural networks are proposed. When a training process in a multilayer perceptron falls into a local minimum or stalls in a flat region, the proposed DCL scheme is applied to divide the current training data region into two easier to be learned regions. The learning process continues when a self-growing perceptron network and its initial weight estimation are constructed for one of the newly partitioned regions. Another partitioned region will resume the training process on the original perceptron network. Data region partitioning, weight estimating and learning are iteratively repeated until all the training data are completely learned by the MPN. We evaluated and compared the proposed MPN with several representative neural networks on the two-spirals problem and real-world dataset. The MPN achieved better weight learning performance by requiring much less data presentations during the network training phases, and better generalization performance, and less processing time during the retrieving phase.
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Affiliation(s)
- H C Fu
- Department of Computer Science and Information Engineering, National Chiao Tung University, Hsinchu, Taiwan 300, R.O.C
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Yang F, Leung KY, Lee YP, Chan HY, Tang MHY. Fetal biometry by an inexperienced operator using two- and three-dimensional ultrasound. Ultrasound Obstet Gynecol 2010; 35:566-71. [PMID: 20183864 DOI: 10.1002/uog.7600] [Citation(s) in RCA: 23] [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] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
OBJECTIVE To compare the reproducibility, accuracy and time required for fetal biometric measurements using two-dimensional (2D) and three-dimensional (3D) ultrasonography by an inexperienced operator. METHODS Fifty consecutive fetuses were evaluated at a gestational age of 17-34 weeks. For every fetus measurements-including biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL)-were made by an inexperienced operator using 2D ultrasound and then saved 3D volumes. As a control, measurements were also made by an experienced operator using 2D ultrasonography alone. Each fetal biometric parameter was measured twice by each operator. All images were assessed by two experienced reviewers, blinded to the operator's identity, using a scoring system based on objective evaluation criteria. RESULTS The interobserver, intraobserver and inter- method variability for 2D ultrasonography by the experienced operator (2D-exp), and 2D and 3D ultrasonography by the inexperienced operator (2D-inexp and 3D-inexp) was small (all intraclass correlation coefficients > or = 0.991). A non-significantly higher proportion of fetal biometric measurements by 3D-inexp than 2D-inexp were within 1 mm of the measurements by 2D-exp. There were no differences in the mean image quality scores of fetal biometry between 2D-exp and 2D-inexp, 2D-exp and 3D-inexp. However, the quality score of AC images obtained by 3D-inexp was greater than that obtained by 2D-inexp (5.5 vs. 5.3, P = 0.018). The mean time required to measure BPD, HC, AC and FL was less for 3D-inexp than for 2D-inexp (67.2 vs. 97.0 s, 64.6 vs. 97.0 s, 60.1 vs. 81.5 s and 65.5 vs. 95.1 s, respectively; all P < 0.001), but was significantly greater than for 2D-exp, with corresponding figures of 24.3, 24.3, 27.9 and 27.2 s. CONCLUSION Fetal biometric measurements obtained by an inexperienced operator using both 2D and 3D ultrasound were reproducible and showed good agreement with those obtained by an experienced operator. The use of 3D ultrasound by an inexperienced operator allows faster measurements to be made than by 2D ultrasound and also seems to facilitate the acquisition of higher-quality images for measurement of AC.
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Affiliation(s)
- F Yang
- Department of Obstetrics and Gynecology, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
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17
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Lam TK, Lau HY, Lee YP, Fung SM, Leung WL, Kam KM. Comparative evaluation of the INNO-LIA syphilis score and the MarDx Treponema pallidum immunoglobulin G Marblot test assays for the serological diagnosis of syphilis. Int J STD AIDS 2010; 21:110-3. [DOI: 10.1258/ijsa.2009.009026] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We evaluated the performance of two immunoblot assays: the INNO-LIA Syphilis Score (LIA) and the MarDx T. pallidum IgG Marblot Test (TWB), as compared with that of the Murex ICE Syphilis enzyme immunoassay (EIA), the Serodia Treponema pallidum particle agglutination (TPPA) assay and the fluorescent treponemal antibody-absorption (FTA-abs) assay, for the serological diagnosis of syphilis using serum samples of 135 attendees of the social hygiene clinics of the Department of Health in Hong Kong newly diagnosed with syphilis and provided with clinical stages (39 in primary, 20 in secondary, 18 in early latent and 58 in latent of unknown duration) and of 43 normal healthy subjects between October and December 2004. The differences in the overall sensitivities of the LIA assay and the EIA/TPPA/FTA-abs assays were not statistically significant ( P > 0.05) whereas the overall sensitivity of the TWB assay was significantly lower ( P < 0.05) than the overall sensitivities of the EIA, the TPPA and the FTA-abs assays. The LIA assay had an overall sensitivity of 94.1% (95% CI 88.7–97.0%) whereas the TWB assay 65.2% (95% CI 56.8–72.7%). Both the LIA and the TWB assays have a specificity of 100%. When consensus results were derived from the most predominant results of the EIA, the TPPA and the FTA-abs assays, the LIA assay had a positive agreement with the consensus results of 98.5% (95% CI 94.5–99.6%) whereas the TWB assay 68.2% (95% CI 59.8–75.6%). Therefore, the LIA assay performed significantly better ( P < 0.05) than the TWB assay. The LIA assay can be considered to be a valid alternative confirmatory test for the serological diagnosis of syphilis.
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Affiliation(s)
- T K Lam
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - H Y Lau
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - Y P Lee
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - S M Fung
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - W L Leung
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - K M Kam
- Microbiology Division, Public Health Laboratory Services Branch, Centre for Health Protection, Department of Health, Hong Kong
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18
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Lee YP, Fleming AJ, Körner C, Meins F. Differential expression of the CBF pathway and cell cycle-related genes in Arabidopsis accessions in response to chronic low-temperature exposure. Plant Biol (Stuttg) 2009; 11:273-283. [PMID: 19470100 DOI: 10.1111/j.1438-8677.2008.00122.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Low, non-freezing temperatures are a major factor limiting growth and development of vegetation in cold climates. Activation of the C-repeat binding factor (CBF) regulatory pathway by acute cold treatment is important for cold acclimation and freezing tolerance in Arabidopsis thaliana; however, the potential role of this pathway in response to chronic cold treatment has been less well characterised. We studied long-term (chronic) effects of low, non-freezing temperatures on the expression of CBF pathway genes (CBF2/3, COR15a, RD29A) and cell cycle-related genes (CDKA;1, CYCD2;1, CYCB1;1) in roots of accessions from habitats differing in growing season temperatures. Elongation rates of primary roots at 21 and 10 degrees C were not significantly correlated with average growing season temperatures, indicating that there is no ecotypic differentiation for these traits. Measurements of mRNA accumulation in roots of seven accessions showed that expression of CBF2/3, COR15a and RD29A is induced by both acute cold treatment (2-24 h at 4 degrees C) and chronic cold treatment (5-6 weeks at 10 degrees C), while CYCB1;1 is only induced by chronic cold treatment. RD29A and COR15a mRNA levels were correlated (P < 0.05) with the rate of root elongation in the cold for three high-altitude accessions relative to the common laboratory stain, Col-0. Our results are consistent with the hypothesis that induction of CBF2/3, COR15a, RD29A and CYCB1;1 is a physiological response to cold that, in the case of RD29A and COR15a, may be important for root growth at low temperatures.
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Affiliation(s)
- Y P Lee
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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19
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Cheong KB, Leung KY, Chan HY, Lee YP, Yang F, Tang MHY. Comparison of inter- and intraobserver agreement between three types of fetal volume measurement technique (XI VOCAL, VOCAL and multiplanar). Ultrasound Obstet Gynecol 2009; 33:287-294. [PMID: 19248036 DOI: 10.1002/uog.6255] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVES To compare the new XI VOCAL (eXtended Imaging Virtual Organ Computer-aided Analysis) for three-dimensional (3D) ultrasound measurement of fetal volume with the conventional multiplanar technique and a rotational method using VOCAL. METHODS We acquired 3D volume datasets from 30 fetuses at 11-14 weeks of gestation using a commercially available ultrasound system. Fetal volume was calculated using XI VOCAL (with 5, 10, 15 and 20 slices), multiplanar (1-mm interval) and VOCAL (with 12 degrees, 18 degrees and 30 degrees rotation) techniques. The level of agreement for interobserver and intraobserver variability was determined and evaluated for all methods and reliability was assessed. RESULTS Fetal volume measurements obtained using XI VOCAL (10 slices) showed good correlation with those obtained using VOCAL (18 degrees) (r = 0.940, P = 0.076; intraclass correlation coefficient (ICC), 0.962 (95% CI, 0.920-0.982), P = 0.182), and XI VOCAL (15 slices) showed good correlation with VOCAL (12 degrees ) (r = 0.961, P = 0.092; ICC, 0.979 (95% CI, 0.957-0.990), P = 0.190). The mean difference between paired measurements by the XI VOCAL (10 slices) and VOCAL (18 degrees ) methods was 1.00 mL, while that by the XI VOCAL (15 slices) and VOCAL (12 degrees) methods was 0.90 mL. 95% limits of agreement were - 2.80 to 4.80 between XI VOCAL (10 slices) and VOCAL (18 degrees) and - 1.90 to 3.70 between XI VOCAL (15 slices) and VOCAL (12 degrees). There was a small difference in the time required to complete the fetal volume measurement between XI VOCAL and VOCAL when a similar number of slices or rotational steps was used (P < 0.05), XI VOCAL taking less time. CONCLUSION XI VOCAL (with 10, 15 and 20 slices) can be used interchangeably with the multiplanar technique (1-mm interval) for the measurement of fetal volume. XI VOCAL (10 slices) and VOCAL (18 degrees) can be used interchangeably, as can XI VOCAL (15 slices) and VOCAL (12 degrees), for the measurement of fetal volume.
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Affiliation(s)
- K B Cheong
- Department of Obstetrics and Gynaecology, The University of Hong Kong, Queen Mary Hospital, Li Ka Shing Faculty of Medicine, Hong Kong, SAR China. cheong kah
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20
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Chen CF, Huang NZ, Gourichon D, Lee YP, Tixier-Boichard M, Bordas A. Effect of introducing the naked neck gene in a line selected for low residual feed consumption on performance in temperate or subtropical environments. Poult Sci 2008; 87:1320-7. [PMID: 18577611 DOI: 10.3382/ps.2008-00002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to investigate the possibility of combining the naked neck gene with a genetic background that has been optimized for feed efficiency of laying hens at moderate temperature. In 1997, the naked neck gene was introduced into a line selected for low residual feed intake. In 2003, after 6 generations of introgression, 8 males and 56 females heterozygous for the NA*NA mutation were used to generate all 3 genotypes (NA*N/NA*N, NA*NA/NA*N, NA*NA/NA*NA), in 2 hatches, for rearing in Taiwan and France, respectively, at 3-wk intervals. Growth performance, anatomical traits, laying traits, and feed efficiency were recorded in each country. In addition, comb and rectal temperatures were measured in Taiwan. Performance was generally lower and mortality of laying hens was higher in Taiwan (11%) than in France (1%). Genotype x environment interactions were rare: genotype x environment was observed only for body weight at 10 wk of age and was close to significance for egg weight. The laying performance was significantly decreased in Taiwan by about 25%. The naked neck genotype had a negative effect on body weight and a positive effect of clutch length and egg weight. It also affected heat dissipation traits such as wattle length and rectal and surface temperature measurements. There was a clear additive and negative effect of the NA*NA mutation on rectal temperature. Feed intake and residual feed intake were increased in the homozygous carriers of the NA*NA mutation, which may improve heat tolerance of the low residual feed consumption (R-) line. Feed efficiency tended to be better in NA*NA/NA*NA hens in both environments. Thus, the introduction of the NA*NA mutation in the R- background appeared to be favorable from the viewpoint of feed efficiency, but it did not improve laying performance in a subtropical environment. Other factors than temperature, such as diet composition and lighting regimen, may be involved.
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Affiliation(s)
- C F Chen
- Department of Animal Science, National Chung-Hsing University, Taichung, Taiwan.
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21
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Li L, Liu E, Goh LZ, Lee YP. Comparison between poly(methyl methacrylate)-carbon black and polyaniline conductive coatings. J Nanosci Nanotechnol 2008; 8:2637-2642. [PMID: 18572698 DOI: 10.1166/jnn.2008.574] [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: 05/26/2023]
Abstract
This work aims to develop and compare two types of conductive, polymer-based coatings via a dip coating process. The first type of coatings was made by dispersing and incorporating carbon black (CB) nanoparticles in a poly(methyl methacrylate) (PMMA) solution followed by dip coating. The CB content and dipping parameters were varied to explore their effects on the particle dispersion, coating thickness, and conductivity of the coatings. The dispersion of the CB particles in the polymer matrix was examined by scanning electron microscopy (SEM), while the coating thickness and conductivity were measured with a surface profilometer and a four-point probe electrometer, respectively. The good dispersion of carbon nanoparticles in the PMMA matrix was observed in the coatings. The conductivity of the PMMA-CB composite coatings was found to be mainly affected by CB content, particle dispersion as well as coating thickness. On the other hand, polyaniline (PANI) was used to make conductive coatings by dip coating and doping, and the advantages and limitations of the PANI coatings were compared with the PMMA-CB coatings.
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Affiliation(s)
- L Li
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore
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22
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Lam VD, Kim JB, Tung NT, Lee SJ, Lee YP, Rhee JY. Dependence of the distance between cut-wire-pair layers on resonance frequencies. Opt Express 2008; 16:5934-5941. [PMID: 18542704 DOI: 10.1364/oe.16.005934] [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
We studied both experimentally and theoretically the influence of the distance between adjacent cut-wire-pair layers on the magnetic and the electric resonances in the microwave-frequency regime. Besides the dependence on the separation between cut-wire pairs, along the electric-field direction, the electric resonance strongly depends on the distance between cut-wire-pair layers, while the magnetic resonance is almost unchanged. This contrast can be understood by the difference in the distribution of induced-charge density and in the direction of the induced current between the electric and magnetic resonances. A simple model is proposed to simulate our experimental results and the simulation results are in good agreement with the experiment. This result provides important information in obtaining left-handed behavior when the cut-wire pairs are combined with the continuous wire.
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Affiliation(s)
- V D Lam
- Quantum Photonic Science Research Center and BK21 Program Division of Advanced Research and Education in Physics, Hanyang University, Seoul 133-791, Korea
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23
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Abstract
Diffracted magneto-optical (MO) effects are numerically investigated for one-dimensional lossy gyrotropic gratings in the zeroth and the first orders for the polar magnetization by utilizing the rigorous coupled-wave approach implemented as an Airy-like internal-reflection series. The simulated Kerr spectra agree well with the experimental ones. The dependence of the MO Kerr enhancement on the grating depth in the first-order diffraction, compared with that in the zeroth one, is illustrated, and the diffracted MO Faraday effect is theoretically investigated as well. Such a MO enhancement through the gyrotropic gratings is superior to the conventional MO devices and magneto-photonic crystals. The potential applications are also suggested.
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Affiliation(s)
- Y H Lu
- Quantum Photonic Science Research Center and BK21 Program Division of Advanced Research and Education in Physics, Hanyang University, Seoul 133-791, Korea
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Berthouly C, Bed'Hom B, Tixier-Boichard M, Chen CF, Lee YP, Laloë D, Legros H, Verrier E, Rognon X. Using molecular markers and multivariate methods to study the genetic diversity of local European and Asian chicken breeds. Anim Genet 2008; 39:121-9. [PMID: 18366475 DOI: 10.1111/j.1365-2052.2008.01703.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- C Berthouly
- AgroParisTech, UMR1236 Génétique et Diversité Animales, 16 rue Claude Bernard, 75321 Paris Cedex 05, France.
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25
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Abstract
Malignant lymph nodes in the neck include metastases and lymphoma. Cervical nodal metastases are common in patients with head and neck cancers, and their assessment is important as it affects treatment planning and prognosis. Neck nodes are also a common site of lymphomatous involvement and an accurate diagnosis is essential as its treatment differs from other causes of neck lymphadenopathy. On ultrasound, grey scale sonography helps to evaluate nodal morphology, whilst power Doppler sonography is used to assess the vascular pattern. Grey scale sonographic features that help to identify metastatic and lymphomatous lymph nodes include size, shape and internal architecture (loss of hilar architecture, presence of intranodal necrosis and calcification). Soft tissue oedema and nodal matting are additional grey scale features seen in tuberculous nodes or in nodes that have been previously irradiated. Power Doppler sonography evaluates the vascular pattern of nodes and helps to identify the malignant nodes. In addition, serial monitoring of nodal size and vascularity are useful features in the assessment of treatment response.
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Affiliation(s)
- A T Ahuja
- Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China.
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26
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Lam VD, Kim JB, Lee SJ, Lee YP, Rhee JY. Dependence of the magnetic-resonance frequency on the cut-wire width of cut-wire pair medium. Opt Express 2007; 15:16651-16656. [PMID: 19550951 DOI: 10.1364/oe.15.016651] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We investigated some magnetic metamaterials based on cut-wire pairs instead of split-ring resonators to quest for the possibility of a negative magnetic permeability. Several periodic structures of cut-wire pairs were designed and fabricated, and their transmission spectra were measured in the microwave-frequency regime. The width dependence of magnetic-resonance frequency was studied both theoretically and experimentally for the periodic structures of cut-wire pairs. It was found that, besides the length dependence, the magnetic-resonance frequency also depends significantly on the width of cut-wire pair. A simple equivalent-circuit model proposed by Zhou et al. [Opt. Lett. 31, 3620-3622 (2006)] was employed to elucidate this interesting phenomenon and to simulate the width dependence. In the simulation the magnetic and the electric energies of the cut-wire pair were directly calculated to obtain the magnetic-resonance frequency. The theoretical results are in good agreement with the experimental ones. It reveals that there is a rather easy way to manipulate the magnetic-resonance frequency of magnetic-magnetic metamaterials.
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Woo BSC, Ng TP, Fung DSS, Chan YH, Lee YP, Koh JBK, Cai Y. Emotional and behavioural problems in Singaporean children based on parent, teacher and child reports. Singapore Med J 2007; 48:1100-1106. [PMID: 18043836] [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: 05/25/2023]
Abstract
INTRODUCTION This study aims to determine the prevalence of emotional and behavioural problems in a community sample of Singaporean children aged 6-12 years, and its agreement according to parent, teacher and child reports. METHODS The Child Behaviour Checklist (CBCL), Teacher Rating Form (TRF) and child report questionnaires for depression and anxiety were administered to a community sample of primary school children. 60 percent of the children sampled (n = 2,139) agreed to participate. Parents of a sub-sample of 203 children underwent a structured clinical interview. RESULTS Higher prevalence of emotional and behavioural problems was identified by CBCL (12.5 percent) than by TRF (2.5 percent). According to parent reports, higher rates of internalising problems (12.2 percent) compared to externalising problems (4.9 percent), were found. Parent-teacher agreement was higher for externalising problems than for internalising problems. Correlations between child-reported depression and anxiety, and parent and teacher reports were low to moderate, but were better for parent reports than for teacher reports. CONCLUSION The prevalence rates of emotional and behavioural problems in Singaporean children based on CBCL ratings are comparable to those in the West, but the low response rate and exclusion of children with special needs limit the generalisability of our findings. Singaporean children have higher rates of internalising problems compared to externalising problems, while Western children have higher rates of externalising problems compared to internalising problems.
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Affiliation(s)
- B S C Woo
- Department of Child and Adolescent Psychiatry, Institute of Mental Health, Child Guidance Clinic, Health Promotion Board Building, 3 Second Hospital Avenue, #03-01, Singapore 168937.
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28
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Abstract
1. Behavioural patterns of 4 slow-growing local breeds of chickens in Taiwan and China, Taiwan Country chickens, Beijing Fatty chickens, pure Silkies, and upgraded commercial Silkies, were studied from 5 to 16 weeks of age as a reference of management for commercial production. 2. Fifteen males and 15 females of the same breed were housed in a pen. Every breed had 6 pens and 24 pens were studied. 3. Taiwan Country chickens displayed more aggressive, sexual and feather pecking behaviours, had less resting time, the fastest feeding rate and used perches more often. The fast-growing and heavy commercial Silkies had more feeding activity and less preening activity. They were also similar to the crested and docile Beijing Fatty chickens and had less stand/walking and more resting time. The pure Silky bantams showed much more foraging activity than the other breeds. 4. When males started to display more aggression and sexual behaviour, after 8-12 weeks of age, resting time for all birds started to decline and stand/walking increased. 5. These results could imply that different local breeds need different housing systems for the bird's welfare.
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Affiliation(s)
- Y P Lee
- Department of Animal Science, National Chung-Hsing University, Taichung, 402 Taiwan.
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29
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Yang KT, Lin CY, Huang HL, Liou JS, Chien CY, Wu CP, Huang CW, Ou BR, Chen CF, Lee YP, Lin EC, Tang PC, Lee WC, Ding ST, Cheng WTK, Huang MC. Expressed transcripts associated with high rates of egg production in chicken ovarian follicles. Mol Cell Probes 2007; 22:47-54. [PMID: 17692502 DOI: 10.1016/j.mcp.2007.06.001] [Citation(s) in RCA: 28] [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] [Received: 06/19/2006] [Revised: 04/06/2007] [Accepted: 06/12/2007] [Indexed: 11/16/2022]
Abstract
The purpose of this study was to characterize differentially expressed transcripts associated with varying rates of egg production in Taiwan country chickens. Ovarian follicles were isolated from two strains of chicken which showed low (B) or high (L2) rates of egg production, then processed for RNA extraction and cDNA library construction. Three thousand and eight forty clones were randomly selected from the cDNA library and amplified by PCR, then used in microarray analysis. Differentially expressed transcripts (P<0.05, log(2)> or = 1.75) were sequenced, and aligned using GenBank. This analysis revealed 20 non-redundant sequences which corresponded to known transcripts. Eight transcripts were expressed at a higher level in ovarian tissue prepared from chicken strain B, and 12 transcripts were expressed at a higher level in L2 birds. These differential patterns of expression were confirmed by semi-quantitative RT-PCR. We show that transcripts of cyclin B2 (cycB2), ferritin heavy polypeptide 1 (FTH1), Gag-Pol polyprotein, thymosin beta4 (TB4) and elongation factor 1 alpha1 (EEF1A1) were enriched in B strain ovarian follicles. In contrast, thioredoxin (TXN), acetyl-CoA dehydrogenase long chain (ACADL), inhibitor of growth family member 4 (ING4) and annexin II (ANXA2) were expressed in at higher levels in the L2 strain. We suggest that our approach may lead to the isolation of effective molecular markers that can be used in selection programs in Taiwan country chickens.
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Affiliation(s)
- K T Yang
- Department of Animal Science, National Chung Hsing University, Taichung, Taiwan
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30
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Lin YF, Chang SJ, Yang JR, Lee YP, Hsu AL. Effects of supplemental vitamin E during the mature period on the reproduction performance of Taiwan Native Chicken cockerels. Br Poult Sci 2005; 46:366-73. [PMID: 16050192 DOI: 10.1080/00071660500098186] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [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: 10/25/2022]
Abstract
One-day-old Taiwan native male chicks were fed with maize-soybean rearing diets without supplemental vitamin E to 23 weeks of age. From 23 to 52 weeks of age, the cockerels (n = 90) were assigned at random to 5 dietary treatments and fed with maize-soybean diets supplemented with 0, 20, 40, 80 and 160 mg/kg of vitamin E (dl-alpha-tocopherol acetate). Pullets (225) of the same age were fed with standard diets throughout. They were artificially inseminated with one dose of 0.04 ml/bird intact and 5-fold diluted pooled semen at 31 to 43 weeks of age and at 49 weeks of age, respectively. The criteria evaluated included: semen quality, fertility and maximum and effective duration of fertility, blood characteristics, body and testes weight. Supplemental vitamin E did not affect cockerels' effective duration of fertility and percentage of fertility. However, when pullets were inseminated with diluted semen, supplementing 160 mg/kg vitamin E increased the maximum duration of fertility at 49 weeks of age. Cockerels receiving 40 to 160mg/kg supplements had higher sperm viability and motility after 39 weeks of age and those fed 80 mg/kg had higher sperm concentration at 39 weeks of age. Cockerels receiving supplements of more than 40 mg/kg vitamin E had higher body weight gain. Plasma cholesterol and testosterone were not affected by supplemental vitamin E. However, plasma luteinising hormone (LH) concentration was lower in cockerels fed 160 mg/kg. Lack of supplemental vitamin E over 39 weeks was associated with lower semen quality but did not reduce the proportion of fertile eggs laid by inseminated hens, perhaps because the insemination dose compensated for low sperm quality. We found that the maximum duration of fertility might be improved by supplementing 160 mg/kg vitamin E at 49 weeks of age.
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Affiliation(s)
- Y F Lin
- The Livestock Research Institute, Council of Agriculture, Tainan, Taiwan
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31
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Leung KY, Lee CP, Tang MHY, Lau ET, Ng LKL, Lee YP, Chan HY, Ma ESK, Chan V. Cost-effectiveness of prenatal screening for thalassaemia in Hong Kong. Prenat Diagn 2005; 24:899-907. [PMID: 15565640 DOI: 10.1002/pd.1035] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [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: 11/12/2022]
Abstract
OBJECTIVES To determine the cost effectiveness of a universal prenatal screening program for alpha- and beta-thalassaemia. METHODS We retrospectively reviewed our program from 1998 to 2002, and calculated the direct and indirect costs of various components. RESULTS 18,936 women were screened at our prenatal clinic and 153 couples were subsequently referred to our Prenatal Diagnostic Centre for counselling and further investigations. In addition, there were 238 tertiary referrals and 157 self-referrals. After investigations, 84 fetuses were at risk of beta-thalassaemia major/beta-E thalassaemia, 19 of them were affected and 18 were aborted. The total expenditure on our program (HK 10.0 million dollars) would be less than the postnatal service costs (HK 40.4 million dollars) for 18beta-thalassaemia major fetuses if they were born. Of 361 women at risk of carrying a homozygous alpha0-thalassaemia fetus, 311 (86.2%) opted for the indirect approach (using serial ultrasound examinations to exclude Hb Bart's disease), and 76 (24.5%) subsequently underwent an invasive test for a definitive diagnosis. The sensitivity and false positive rate of this indirect approach was 100.0% and 2.9% respectively. CONCLUSION It is cost effective to run a universal prenatal screening program in an area where both beta-thalassaemia and alpha-thalassaemia are prevalent. The indirect approach can effectively avoid an invasive test in unaffected pregnancies.
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Affiliation(s)
- K Y Leung
- Department of Obstetrics & Gynaecology, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China.
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Peterkova V, Savoy C, Bezlepkina O, Ivanov A, Orlova E, Nagaeva E, Kim J, Lee YP, Saenger PH, Stanhope R. Efficacy and safety of Valtropin in the treatment of short stature in girls with Turner's syndrome. J Pediatr Endocrinol Metab 2004; 17:1429-34. [PMID: 15526722 DOI: 10.1515/jpem.2004.17.10.1429] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Valtropin (somatropin, BioPartners and LG Life Sciences [LGLS]) is a recombinant human growth hormone (GH) preparation produced using a yeast expression system. An open single-arm phase III study was conducted to evaluate efficacy and safety at a dose of 0.16 IU/kg/day (0.053 mg/kg/day) s.c. for 12 months in the treatment of short stature in girls (n = 30, aged 2-9 years) with Turner's syndrome. The primary efficacy variable was height velocity (HV) at 12 months. Secondary efficacy variables included serum GH dependent growth factors. HV increased from 3.8 +/- 1.8 cm/yr at baseline to 9.7 +/- 1.6 cm/yr (mean +/- SD) after 12 months of treatment. Marked treatment effects were also observed on other growth parameters, serum insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3). Treatment was well tolerated with no significant adverse events. It is concluded that Valtropin is as safe and effective as other human GH preparations for the treatment of growth failure in girls with Turner's syndrome.
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Affiliation(s)
- V Peterkova
- Endocrinological Scientific Centre of Russian Academy of Science, Paediatric Endocrinology, Moscow, Russia
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Lee YP, Fung DSS, Koh JBK, Wei KC, Woo BSC, Teo J. Between the rod and reason: a study on Asian parental disciplinary methods and child emotional/behavioural outcomes. Ann Acad Med Singap 2004; 33:S27-8. [PMID: 15651193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Affiliation(s)
- Y P Lee
- Institute of Mental Health, Department of Child and Adolescent Psychiatry, Singapore
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Lee YP, Griffith JF, Antonio GE, Tang N, Leung KS. Early magnetic resonance imaging of radiographically occult osteoporotic fractures of the femoral neck. Hong Kong Med J 2004; 10:271-5. [PMID: 15299173] [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: 04/30/2023] Open
Abstract
Osteoporosis is associated with thinning of cortical and trabecular bone, which reduces bone strength and predisposes individuals to fracture development. Femoral neck fractures in patients with osteoporosis may not be apparent on radiographs. Magnetic resonance imaging is useful at detecting these radiographically occult fractures; yet, the practice has not been widely adopted in Hong Kong. In this article, we review our experience of early magnetic resonance imaging in this clinical context--that is, imaging performed within 48 hours of presentation to hospital. Twenty-eight patients (age range, 69-93 years) over a 3-year period were studied. Magnetic resonance imaging revealed radiographically occult neck fractures in 14 (50%) cases (equivalent to 4% of all femoral neck fractures). These fractures were treated surgically (64%) or conservatively (36%) with good bone healing and clinical outcome. When no femoral neck fracture was present, magnetic resonance imaging revealed an alternative cause for symptoms in all 14 cases. We strongly endorse the use of early magnetic resonance imaging for patients with osteoporosis who have a clinically suspected femoral neck fracture that is not visible radiographically.
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Affiliation(s)
- Y P Lee
- Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
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35
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An JY, Yun HS, Lee YP, Yang SJ, Shim JO, Jeong JH, Shin CY, Kim JH, Kim DS, Sohn UD. The intracellular pathway of the acetylcholine-induced contraction in cat detrusor muscle cells. Br J Pharmacol 2002; 137:1001-10. [PMID: 12429572 PMCID: PMC1573577 DOI: 10.1038/sj.bjp.0704954] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. The present study was aimed to investigate intracellular pathways involved in acetylcholine (ACh)-induced contraction in cat detrusor muscle cells 2. Contraction was expressed as per cent shortening of length of individually isolated smooth muscle cells obtained by enzymatic digestion. Dispersed intact and permeabilized cells were prepared for the treatment of drugs and antibody to enzymes, respectively. Using Western blot, we confirmed the presence of related proteins. 3. The maximal contraction to ACh was generated at 10(-11) M. This response was preferentially antagonized by M3 muscarinic receptor antagonist rho-fluoro-hexahydrosiladifenidol (rhoF-HSD) but not by the M1 antagonist pirenzepine and the M2 muscarinic receptor antagonist methoctramine. We identified G-proteins (Gq/11), (Gs), (G0), (Gi1), (Gi2) and (Gi3) in the bladder detrusor muscle. ACh-induced contraction was selectively inhibited by (Gq/11) antibody but not to other G subunit. 4. The phosphatidylinositol-specific phospholipase C (PI-PLC) inhibitor neomycin reduced ACh-induced contraction. However, the inhibitors of the phospholipase D, the phospholipase A2 and protein kinase C did not attenuate the ACh-induced contraction. ACh-induced contraction was inhibited by antibody to PLC-beta1 but not PLC-beta3 and PLC-gamma. Thapsigargin or strontium, which depletes or blocks intracellular calcium release, inhibited ACh-induced contraction. Inositol 1,4,5-triphosphate IP3 receptor inhibitor heparin reduced ACh-induced contraction. 5. These results suggest that in cat detrusor muscle contraction induced by ACh is mediated via M3 muscarinic receptor-dependent activation of Gq/11 and PLC-beta1 and IP3-dependent Ca(2+) release.
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Affiliation(s)
- J Y An
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - H S Yun
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - Y P Lee
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - S J Yang
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - J O Shim
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - J H Jeong
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - C Y Shin
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - J H Kim
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - D S Kim
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
| | - U D Sohn
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, 156-756, Republic of Korea
- Author for correspondence:
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36
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Kang HY, Lee TS, Lee YP, Lee DW, La HO, Song HJ, Sohn UD. Interaction of calmodulin- and PKC-dependent contractile pathways in cat lower esophageal sphincter (LES). Arch Pharm Res 2001; 24:546-51. [PMID: 11794533 DOI: 10.1007/bf02975163] [Citation(s) in RCA: 2] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have previously shown that, in circular muscle cells of the lower esophageal sphincter (LES) isolated by enzymatic digestion, contraction in response to maximally effective doses of acetylcholine (ACh) or Inositol Triphosphate (IP3) depends on the release of Ca2+ from intracellular stores and activation of a Ca2+-calmodulin (CaM)-dependent pathway. On the contrary, maintenance of LES tone, and response to low doses of ACh or IP3 depend on a protein kinase C (PKC) mediated pathway. In the present investigation, we have examined requirements for Ca2+ regulation of the interaction between CaM- and PKC-dependent pathways in LES contraction. Thapsigargin (TG) treatment for 30 min dose dependently reduced ACh-induced contraction of permeable LES cells in free Ca2+ medium. ACh-induced contraction following the low level of reduction of Ca2+ stores by a low dose of TG (10(-9) M) was blocked by the CaM antagonist, CGS9343B but not by the PKC antagonists chelerythrine or H7, indicating that the contraction is CaM-dependent. After maximal reduction in intracellular Ca2+ from Ca2+ stores by TG (10(-6) M), ACh-induced contraction was blocked by chelerythrine or H7, but not by CGS9343B, indicating that it is PKC-dependent. In normal Ca2+ medium, the contraction by ACh after TG (10(-9) M) treatment was also CaM-dependent, whereas the contraction by ACh after TG (10(-9) M) treatment was PKC-dependent. We examined whether PKC activation was inhibited by activated CaM. CGS 9343B inhibited the CaM-induced contraction, but did not inhibit the DAG-induced contraction. CaM inhibited the DAG-induced contraction in the presence of CGS 9343B. This inhibition by CaM was Ca2+ dependent. These data are consistent with the view that the switch from a PKC-dependent pathway to a CaM dependent pathway can occur and can be regulated by cytosolic Ca2+ in the LES.
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Affiliation(s)
- H Y Kang
- Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul, Republic of Korea
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Abstract
Two experiments were conducted to investigate the relationships among reproductive performance, serum gamma-globulin level, carbon clearance ability, and immune responses to phytohemagglutinin and SRBC in the Taiwan Country chicken. In Experiment 1, 480 pullets from 82 sires and 204 dams were used to evaluate the relationship between reproductive performance and immunity. In Experiment 2, 480 pullets, offspring from 55 sires and 173 dams expressing a high or low percentage of serum gamma-globulin and their reciprocal crosses, were used to examine if the level of serum gamma-globulin is associated with reproductive performance and immunity. Results of these experiments indicated that 1) the Taiwan Country chicken had relatively high serum gamma-globulin level compared with those in other reports, 2) serum gamma-globulin level in the Taiwan Country chicken is heritable with an estimate around 0.3 to 0.4, and 3) the high serum gamma-globulin level is genetically associated with low fertility.
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Affiliation(s)
- C H Chao
- Department of Animal Science, National Chiayi University, Taiwan, Republic of China.
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38
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Chang GS, Lee YP, Rhee JY, Lee J, Jeong K, Whang CN. Realization of a large magnetic moment in the ferromagnetic CoPt bulk phase. Phys Rev Lett 2001; 87:067208. [PMID: 11497857 DOI: 10.1103/physrevlett.87.067208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2000] [Indexed: 05/23/2023]
Abstract
Changes in the magnetic moment and other physical properties of a CoPt alloy induced by a new type of ion-beam mixing in an external magnetic field were investigated. This process induces the formation of a metastable phase through extremely rapid quenching from well above the ordering temperature. The measured magnetic moment per Co atom was 2.63 mu(B), larger by 55% and 35% than that of the bulk Co and stable CoPt film, respectively, which is one of the highest values ever observed in the ferromagnetic bulk phase.
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Affiliation(s)
- G S Chang
- ASSRC and IPAP, Yonsei University, Seoul 120-749, Korea.
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Abstract
This study attempted to clarify the relationship between the levels of 70kDa heat shock protein (HSP70) and semen quality in boars. Semen samples from 29 (13 Duroc, 9 Landrace, and 7 Yorkshire) boars (mean age=25.2+/-2.2 months) were examined. Three to four ejaculates per boar, collected during cool and hot seasons, were evaluated in terms of the sperm concentration, sperm motility, percentage of normal and abnormal sperm, as well as percentage of sperm with proximal and distal plasma droplets. Significant seasonal and breed differences in semen quality were observed. Experimental results indicate that the semen quality of Landrace boars was better than those of Yorkshire and Duroc boars (P<0.05) and semen quality declined significantly during the hot season (P<0.05). One-dimensional SDS-PAGE analysis of spermatozoa proteins indicated that protein profiles did not significantly differ between seasons and among breeds. Both constitutive and stress-inducible form of HSP70 were detected in boar spermatozoa by Western blot analysis. The level of HSP70, which revealed no difference among breeds within a season, was significantly lower during the hot season in all the three breeds (P<0.05). Although there appeared to be low correlation coefficients between the level of HSP70 and semen quality traits, the semen quality tended to decline significantly in samples with a lower level of HSP70. Results in this study suggest that the levels of HSP70 in boar spermatozoa are significantly lower during the hot season and might be associated with semen quality.
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Affiliation(s)
- S Y Huang
- Department of Comparative Medicine, Pig Research Institute Taiwan, P. O. Box 23, Chunan 350, ROC, Miaoli, Taiwan
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Huang SY, Kuo YH, Tsou HL, Lee YP, King YT, Huang HC, Yang PC, Lee WC. The decline of porcine sperm motility by geldanamycin, a specific inhibitor of heat-shock protein 90 (HSP90). Theriogenology 2000; 53:1177-84. [PMID: 10798494 DOI: 10.1016/s0093-691x(00)00262-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Sperm motility is an important parameter for fertility. The molecular mechanisms of mammalian sperm motility are still largely undefined. Our previous observations suggested that heat shock protein 90 (HSP90) may be associated with porcine sperm motility. The aim of the present study was to further characterize the plausible novel function of HSP90 on sperm motility. Semen from normal, sexually mature boars with sperm motility higher than 80% was used. An HSP90-specific inhibitor, geldanamycin (GA), was added to diluted semen at 0.5, 1.0, 2.5 or 5.0 microg/mL and the semen was then incubated at 37 degrees C for 15, 30, 45 or 60 min. Sperm motility was determined by using computer-assisted semen analyzer at the end of incubation. The results indicated that GA significantly reduced sperm motility in a dose and time dependent manner. Moreover, incubation of semen with 5.0 microg/mL GA for 15 min completely stopped sperm motility. To test the reversibility of the GA effect on sperm motility, GA was removed after 30 min incubation and was replaced with fresh extender alone or with extender plus 5 mM caffeine, then incubated for another 15, 30, 45 or 60 min. The results showed that simply removing GA did not reverse the inhibitory effect on sperm motility, while adding caffeine partially reversed this inhibitory effect. However, the effect of 2.5 or 5.0 microg/mL GA was not reversed by caffeine. Considering the specificity of GA targeting to HSP90, the above observations suggested that HSP90 may play a crucial role in regulating porcine sperm motility.
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Affiliation(s)
- S Y Huang
- Department of Comparative Medicine, Pig Research Institute Taiwan, Miaoli, Republic of China
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41
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Cheng BM, Chew EP, Liu CP, Bahou M, Lee YP, Yung YL, Gerstell MF. Photo-induced fractionation of water isotopomers in the Martian atmosphere. Geophys Res Lett 1999; 26:3657-3660. [PMID: 11543402 DOI: 10.1029/1999gl008367] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The history and size of the water reservoirs on early Mars can be constrained using isotopic ratios of deuterium to hydrogen. We present new laboratory measurements of the ultraviolet cross-sections of H2O and its isotopomers, and modeling calculations in support of a photo-induced fractionation effect (PHIFE), that reconciles a discrepancy between past theoretical modeling and recent observations. This supports the hypothesis that Mars had an early warm atmosphere and has lost at least a 50-m global layer of water. Likely applications of PHIFE to other planetary atmospheres are sketched.
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Affiliation(s)
- B M Cheng
- Synchrotron Radiation Research Center, Hsinchu, Taiwan
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Abstract
One-hundred-and-twenty cockerels of Strain L2 Taiwan Country chicken from the National Chung-Hsing University were tested for their behavioural responses to semen collection at 21 to 30, 34 to 43 and 57 to 66 weeks of age. At every age period, semen was collected from every cockerel 4 times within a 1-week period. 2. Cockerel performances on most semen traits, including volume, concentration, total number of sperm, ease of collection and sensitivity to massage were very consistent within each age period. 3. Males that did not respond nervously to handling or were less sensitive to massage appeared to produce less semen. However, contamination was more serious in males that responded very nervously or were very sensitive to massage. 4. Sensitivity to massage, like semen volume, is an invariant character as indicated by the high correlation between measures taken at different age periods.
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Affiliation(s)
- Y P Lee
- National Chung-Hsing University, Taichung, Taiwan
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Lieberman JR, Daluiski A, Stevenson S, Wu L, McAllister P, Lee YP, Kabo JM, Finerman GA, Berk AJ, Witte ON. The effect of regional gene therapy with bone morphogenetic protein-2-producing bone-marrow cells on the repair of segmental femoral defects in rats. J Bone Joint Surg Am 1999; 81:905-17. [PMID: 10428121 DOI: 10.2106/00004623-199907000-00002] [Citation(s) in RCA: 383] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Recombinant human bone morphogenetic proteins (rhBMPs) can induce bone formation, but the inability to identify an ideal delivery system limits their clinical application. We used ex vivo adenoviral gene transfer to create BMP-2-producing bone-marrow cells, which allow delivery of the BMP-2 to a specific anatomical site. The autologous BMP-2-producing bone-marrow cells then were used to heal a critical-sized femoral segmental defect in syngeneic rats. METHODS Femoral defects in five groups of rats were filled with 5 x 10(6) BMP-2-producing bone-marrow cells, created through adenoviral gene transfer (twenty-four femora, Group I); twenty micrograms of rhBMP-2 (sixteen femora, Group II); 5 x 10(6) beta-galactosidase-producing rat-bone-marrow cells, created through adenoviral gene transfer of the lacZ gene (twelve femora, Group III); 5 x 10(6) uninfected rat-bone-marrow cells (ten femora, Group IV); or guanidine hydrochloride-extracted demineralized bone matrix only (ten femora, Group V). Guanidine hydrochloride-extracted demineralized bone matrix served as a substrate in all experimental groups. Specimens that were removed two months postoperatively underwent histological and histomorphometric analysis as well as biomechanical testing. RESULTS Twenty-two of the twenty-four defects in Group I (BMP-2-producing bone-marrow cells) and all sixteen defects in Group II (rhBMP-2) had healed radiographically at two months postoperatively compared with only one of the thirty-two defects in the three control groups (beta-galactosidase-producing rat-bone-marrow cells, uninfected rat-bone-marrow cells, and guanidine hydrochloride-extracted demineralized bone matrix alone). Histological analysis of the specimens revealed that defects that had received BMP-2-producing bone-marrow cells (Group I) were filled with coarse trabecular bone at two months postoperatively, whereas in those that had received rhBMP-2 (Group II) the bone was thin and lace-like. Defects that had been treated with bone-marrow cells producing beta-galactosidase (Group III), uninfected bone-marrow cells (Group IV), or guanidine hydrochloride-extracted demineralized bone matrix only (Group V) demonstrated little or no bone formation. Histomorphometric analysis revealed a significantly greater total area of bone formation in the defects treated with the BMP-2-producing bone-marrow cells than in those treated with the rhBMP-2 (p = 0.036). Biomechanical testing demonstrated no significant differences, with the numbers available, between the healed femora that had received BMP-2-producing bone-marrow cells and the untreated (control) femora with respect to ultimate torque to failure or energy to failure. CONCLUSIONS This study demonstrated that BMP-2-producing bone-marrow cells created by means of adenoviral gene transfer produce sufficient protein to heal a segmental femoral defect. We also established the feasibility of ex vivo gene transfer with the use of biologically acute autologous short-term cultures of bone-marrow cells.
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Affiliation(s)
- J R Lieberman
- Department of Orthopaedic Surgery, University of California at Los Angeles, 90095, USA
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Chiu HC, Hsiue GH, Lee YP, Huang LW. Synthesis and characterization of pH-sensitive dextran hydrogels as a potential colon-specific drug delivery system. J Biomater Sci Polym Ed 1999; 10:591-608. [PMID: 10357268 DOI: 10.1163/156856299x00504] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
pH-Sensitive dextran hydrogels were prepared by activation of dextran (T-70) with 4-nitrophenyl chloroformate, followed by conjugation of the activated dextran with 4-aminobutyric acid and cross-linking with 1,10-diaminodecane. The cross-linking efficiencies determined by mechanical measurements were in the range of 52-63%. Incorporation of carboxylpropyl groups in dextran hydrogels led to a higher equilibrium and faster swelling under high pH conditions. The swelling reversibility of hydrogels was also observed after repeated changes in buffers between pH 2.0 and 7.4. The slow rates of swelling and deswelling in response to changes in pH were attributed to the hydrophilic nature of dextran and formation of hydrogen bonds between the hydroxyl groups of dextran with water molecules. The pronounced effect of carboxylic acid content on degradation of hydrogels was observed after 4 h of incubation with dextranase and the influence significantly decreased after exposure to the enzyme for 8 h. The mechanism of bulk degradation of hydrogels under high swelling extent was substantiated using Coomassie blue protein assay. The release rate of bovine serum albumin from hydrogels was primarily determined by the swelling extent. The release rate was further enhanced by addition of dextranase in buffer solutions.
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Affiliation(s)
- H C Chiu
- Department of Chemical Engineering, National Chung Hsing University, Taichung, Taiwan, Republic of China
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Huang SY, Kuo YH, Lee WC, Tsou HL, Lee YP, Chang HL, Wu JJ, Yang PC. Substantial decrease of heat-shock protein 90 precedes the decline of sperm motility during cooling of boar spermatozoa. Theriogenology 1999; 51:1007-16. [PMID: 10729022 DOI: 10.1016/s0093-691x(99)00046-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [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: 10/17/2022]
Abstract
The decline in boar semen quality after cryopreservation may be attributed to changes in intracellular proteins. Thus, the aim of the present study was to evaluate the change of protein profiles in boar spermatozoa during the process of cooling and after cryopreservation. A total of 9 sexually mature boars (mean age = 25.5+/-12.3 mo) was used. Samples for protein analysis were collected before chilling, after cooling to 15 degrees C, after cooling to 5 degrees C, following thawing after freezing to -100 degrees C, and following thawing after 1 wk of cryopreservation at -196 degrees C. Semen characteristics evaluated included progressive motility and the percentage of morphologically normal spermatozoa. Total proteins from 5x10(6) spermatozoa were separated and analyzed by SDS-PAGE. The results revealed that there was a substantial decrease of a 90 kDa protein in the frozen-thawed spermatozoa. Western blot analysis demonstrated that this protein was 90 kDa heat-shock protein (HSP90). Time course study showed that the decrease of HSP90 in spermatozoa initially occurred in the first hour during cooling to 5 degrees C. When compared with the fresh spermatozoa before chilling, there was a 64% decrease of HSP90 in spermatozoa after cooling to 5 degrees C. However, the motility and percentage of normal spermatozoa did not significantly decrease during this period of treatment. Both declined substantially as the semen was thawed after freezing from -100 degrees C. The results indicated that the decrease of HSP90 precedes the decline of semen characteristics. The length of time between a decrease of HSP90 and the decline in sperm motility was estimated to be 2 to 3 h. Taken together, the above results suggested that a substantial decrease of HSP90 might be associated with a decline in sperm motility during cooling of boar spermatozoa.
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Affiliation(s)
- S Y Huang
- Department of Comparative Medicine, Pig Research Institute Taiwan, Republic of China.
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Abstract
Effects of barbiturates have been linked to the inhibitory GABAA receptor in the brain. The present study examines changes in the expression of GABAA receptor in the hippocampus of pentobarbital treated rat. Intraperitoneal pentobarbital injections were administered once daily for 9 days at an increasing dose schedule, 30 mg/kg at day 1-3, 60 mg/kg day 4-6, and 90 mg/kg day 7-9. Within each of the three dosage periods, the duration of sleep and extent of reduction in body temperature of the rats decreased with time. Two hours after the 9th injection, 3H-muscimol binding of the hippocampal homogenates of the animals showed that the maximal number of binding sites (Bmax), 10.2 +/- 1.6 pmol/mg protein, was not significantly greater than 9.5 +/- 1.2 of saline control, but strikingly about 7-fold control level of beta 1 mRNA was seen in the pyramidal cells of CA1 and CA2, as revealed by in situ hybridization analysis with digoxigenin-cRNA probes. However, when the rats were withdrawn from pentobarbital injection for 24 hours and 7 days, the Bmax of the hippocampi was lowered to 7.3 +/- 1.0 and 5.1 +/- 0.7, respectively, and the expression of beta 1 mRNA in CA1-2 returned toward control. The pentobarbital treatment did not significantly alter the affinity of the radioligand to the receptor in the hippocampus and the expression of beta 1 mRNA in CA3 and CA4. The results suggest the plasticity of the beta 1 mRNA in CA1-2 as well as differential involvement of CA1-2 and CA3-4 in response to the pentobarbital perturbation.
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Affiliation(s)
- H S Yin
- Department of Anatomy, College of Medicine, National Taiwan University, Taipei, Republic of China.
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Cheng BM, Chew EP, Hung WC, Eberhard J, Lee YP. Photoionization studies of sulfur radicals and products of their reactions. J Synchrotron Radiat 1998; 5:1041-1043. [PMID: 15263738 DOI: 10.1107/s0909049597016075] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 11/10/1997] [Indexed: 05/24/2023]
Abstract
A discharge flow-photoionization mass spectrometric system coupled to a synchrotron is employed to study intermediates and products of sulfur radical reactions related to atmospheric chemistry. Sulfur radicals are generated from reactions of oxygen or chlorine atoms with sulfur compounds in a flow tube. The gaseous reaction products are sampled into the ionization region via a three-stage differential pumping scheme. Photoionization spectra and ionization energies are measured by dispersing synchrotron radiation to ionize the samples. Using this technique, photoionization spectra and ionization energies of HSO, CH(3)SO, C(2)H(5)SO, HSCl, and some secondary reaction products, SSCl, HSSCl, HSSSH, CH(3)SOH and CH(3)SS(O)CH(3), were measured for the first time.
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Affiliation(s)
- B M Cheng
- Synchrotron Radiation Research Center, No. 1, R&D Road VI, Hsinchu Science-Based Industrial Park, Hsinchu 30077, Taiwan
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Adimoolam S, Lee YP, Jonas A. Mutagenesis of highly conserved histidines in lecithincholesterol acyltransferase: identification of an essential histidine (His 377). Biochem Biophys Res Commun 1998; 243:337-41. [PMID: 9480810 DOI: 10.1006/bbrc.1997.7995] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lecithin-cholesterol acyltransferase (LCAT) is responsible for the formation of cholesterol esters in plasma and is implicated in the removal of excess cholesterol from peripheral tissues. It is generally accepted that the catalytic mechanism of LCAT is similar to that of serine proteases and lipases involving a Ser, a His, and an acidic amino acid residue. Ser181 in LCAT has been previously identified as a catalytic residue; however, the active site His and acidic residue have not yet been identified. In this study we have used a variety of approaches to identify the putative active site histidine. Alignments of LCAT sequences across various species indicate that the four histidines at positions 180, 263, 368, and 377 are conserved and could be involved in catalysis. Based on the observation that the members of the triad preserve the same orientation in the primary sequence of a large number of lipases, we eliminated His180 as a potential candidate. Mutational analysis along with functional assays show that, in contrast to the replacement of His263 and His368, the replacement of the His at position 377 with Gly, Ala, or Ser obliterates LCAT activity with interfacial and water-soluble substrates, thus indicating a role of His377 in catalysis.
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Affiliation(s)
- S Adimoolam
- Department of Biochemistry, College of Medicine at Urbana-Champaign, University of Illinois 61801, USA
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Chang SP, Kuo JM, Lee YP, Lu CM, Ling KJ. Transformation of gaussian to coherent uniform beams by inverse-gaussian transmittive filters. Appl Opt 1998; 37:747-752. [PMID: 18268648 DOI: 10.1364/ao.37.000747] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Several plano-convex aluminum thin films, ~30 nm thick in the center and ~2 mm in diameter, were deposited on microscope cover slides to function as inverse-Gaussian transmittive filters. By placing one of these filters in front of the Gaussian He-Ne laser, we can modify the beam intensity profile in the downstream direction. To yield a uniform beam, the position of the filter must be aligned in the transverse plane for maximum intensity at the output of the filter. These filters are easy to fabricate and are inexpensive. Most important, they can help produce collimated phase-coherent uniform beams, which are useful in high-precision fringe-analysis techniques.
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Yum DY, Lee YP, Pan JG. Cloning and expression of a gene cluster encoding three subunits of membrane-bound gluconate dehydrogenase from Erwinia cypripedii ATCC 29267 in Escherichia coli. J Bacteriol 1997; 179:6566-72. [PMID: 9352901 PMCID: PMC179580 DOI: 10.1128/jb.179.21.6566-6572.1997] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [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: 02/05/2023] Open
Abstract
We have cloned the gene cluster encoding three subunits of membrane-bound gluconate dehydrogenase (GADH) from Erwinia cypripedii ATCC 29267 in Escherichia coli by performing a direct-expression assay. The positive clone converted D-gluconate to 2-keto-D-gluconate (2KDG) in the culture medium. Nucleotide sequence analysis of the GADH clone revealed that the cloned fragment contained the complete structural genes for a 68-kDa dehydrogenase subunit, a 47-kDa cytochrome c subunit, and a 24-kDa subunit of unknown function and that the genes were clustered with the same transcriptional polarity. Comparison of the deduced amino acid sequences and the NH2-terminal sequences determined for the purified protein indicated that the dehydrogenase, cytochrome c, and 24-kDa subunits contained typical signal peptides of 22, 19, and 42 amino acids, respectively. The molecular masses of the processed subunits deduced from the nucleotide sequences (65, 45, and 20 kDa) coincided well with the molecular masses of subunits estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In E. cypripedii and recombinant E. coli, the GADH was constitutively formed and the activity of GADH was enhanced more than twofold by addition of D-gluconate to the medium. The holoenzyme glucose dehydrogenase of E. coli was reconstituted by addition of pyrroloquinoline quinone to the culture medium, and the conversion of D-glucose or D-gluconate to 2KDG by recombinant E. coli harboring the cloned GADH gene was attempted in batch culture. The conversion yields for D-glucose were 0.95 mol of 2KDG/mol of D-glucose after 16 h of cultivation, and those for D-gluconate were 0.95 mol of 2KDG/mol of D-gluconate after 12 h of cultivation.
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Affiliation(s)
- D Y Yum
- Bioprocess Engineering Division, Korea Research Institute of Bioscience and Biotechnology, Yusong, Taejon, Korea
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