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Hong MH, Chang CK. [Mechanisms by which the bone marrow microenvironment of myelodysplastic neoplasms contributes to disease progression]. Zhonghua Xue Ye Xue Za Zhi 2023; 44:350-352. [PMID: 37357010 PMCID: PMC10282869 DOI: 10.3760/cma.j.issn.0253-2727.2023.04.018] [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] [Received: 08/21/2022] [Indexed: 06/27/2023]
Affiliation(s)
- M H Hong
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - C K Chang
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
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Hardenberg MC, Patel B, Matthews C, Califano R, Garcia Campelo R, Grohe C, Hong MH, Liu G, Lu S, de Marinis F, Pérol M, Soo RA, Stiles BM, Tiseo M, Tsuboi M. The value of disease-free survival (DFS) and osimertinib in adjuvant non-small-cell lung cancer (NSCLC): an international Delphi consensus report. ESMO Open 2022; 7:100572. [PMID: 36108559 PMCID: PMC9588882 DOI: 10.1016/j.esmoop.2022.100572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/19/2022] [Indexed: 11/04/2022] Open
Abstract
Background Rates of disease recurrence and death following surgery remain high in early-stage non-small-cell lung cancer (NSCLC), despite adjuvant treatment and curative intent. Recently, osimertinib showed overwhelming evidence for disease-free survival (DFS), as demonstrated by an overall reduction in the risk of disease recurrence or death in the adjuvant setting of 80% versus control in the ADAURA study (stage IB-IIIA; hazard ratio 0.20; 99.12% confidence interval 0.14-0.30; P < 0.001). However, due to the early unblinding of ADAURA and lack of mature overall survival data, there is a need to qualitatively confirm consensus on the clinical and patient relevance of DFS. Materials and methods We conducted a modified Delphi panel study consisting of two rounds of surveys, followed by a consensus meeting. An international panel of experts in the field of NSCLC and epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) (n = 13) was asked to rate agreement and comment on a list of pre-defined statements covering key consensus gaps. Statements were eliminated or updated between surveys, depending on the level of agreement. A final list of agreed-upon statements was drafted in the consensus meeting. Results Consensus was reached on 32 qualitative statements, with topics including unmet needs in early-stage NSCLC, the value of DFS, and the value of osimertinib. Crucially, DFS was agreed to be a clinically and patient-relevant endpoint in adjuvant NSCLC. The relevance of DFS was found to relate to the ability of an adjuvant therapy, such as osimertinib, to keep patients in the clinically valuable curative intent setting, while preventing the burden associated with distant and locoregional recurrence, and progressive disease. Conclusions Addressing the need for measures that reflect clinical benefit is essential to continue improving outcomes for NSCLC patients. To that end, this work provides a qualitative framework for clinicians to consider the clinical and patient relevance of DFS in adjuvant NSCLC and the benefit demonstrated in ADAURA thus far. There is a need for qualitative consensus assessment of the clinical and patient relevance of DFS in the adjuvant setting. An international panel of experts viewed DFS as a clinically and patient-relevant endpoint in adjuvant NSCLC. DFS relevance in adjuvant therapy, e.g. osimertinib, relates to keeping early-stage patients in a curative intent setting. Curative intent prevents or significantly delays locoregional and distant (CNS) recurrence burden and progressive disease.
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Affiliation(s)
| | - B Patel
- Charles River Associates, Cambridge, UK
| | | | - R Califano
- Department of Medical Oncology, The Christie NHS Foundation Trust and Division of Cancer Sciences, The University of Manchester, Manchester, UK
| | - R Garcia Campelo
- Coruña University Hospital, Medical Oncology Unit, Coruña, Spain
| | - C Grohe
- Department of Respiratory Diseases, ELK Thorax Center, Berlin, Germany
| | - M H Hong
- Division of Medical Oncology, Department of Internal Medicine, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - G Liu
- University of Toronto, Princess Margaret Cancer Centre, Toronto, Canada
| | - S Lu
- Department of Shanghai Lung Cancer Center, Shanghai Jiao Tong University, Shanghai Chest Hospital, Shanghai, China
| | - F de Marinis
- European Institute of Oncology, IRCCS, Milan, Italy
| | - M Pérol
- Medical Oncology Department, Léon Bérard Cancer Center, Lyon, France
| | - R A Soo
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, Singapore
| | - B M Stiles
- Albert Einstein College of Medicine, Montefiore Health System, Cardiothoracic and Vascular Surgery, New York, USA
| | - M Tiseo
- University of Parma, Department of Medicine and Surgery and Medical Oncology Unit, University Hospital of Parma, Parma, Italy
| | - M Tsuboi
- Department of Thoracic Surgery and Oncology, National Cancer Center Hospital East, Kashiwa, Japan
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Ding X, Xie YL, Xia L, Liu YP, You R, Hong MH, Chen MY. [Exploration of surgical treatment of newly untreated nasopharyngeal carcinoma]. Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2021; 56:772-776. [PMID: 34344110 DOI: 10.3760/cma.j.cn115330-20200827-00698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- X Ding
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou 510060, China State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou 510060, China
| | - Y L Xie
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou 510060, China State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou 510060, China
| | - L Xia
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou 510060, China State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou 510060, China
| | - Y P Liu
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou 510060, China State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou 510060, China
| | - R You
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou 510060, China State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou 510060, China
| | - M H Hong
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou 510060, China Department of Clinical Research, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - M Y Chen
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou 510060, China State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou 510060, China
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Tang SH, Yuan Y, Xie ZH, Chen MJ, Fan XD, Guo YH, Hong MH, Tao SH, Yu N. Enterovirus D68 in hospitalized children with respiratory symptoms in Guangdong from 2014 to 2018: Molecular epidemiology and clinical characteristics. J Clin Virol 2021; 141:104880. [PMID: 34153861 DOI: 10.1016/j.jcv.2021.104880] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/26/2021] [Accepted: 06/02/2021] [Indexed: 01/23/2023]
Abstract
BACKGROUND Enterovirus D68 (EV-D68) is an emerging pathogen in humans. EV-D68 causes a wide range of respiratory symptoms in children and has the propensity to cause severe complications. EV-D68 outbreaks are rarely investigated in mainland China. Therefore, in this study, we aimed to investigate the prevalence of EV-D68 in children and to describe the clinical manifestations as well as the phylogeny of EV-D68 in Guangdong Province from 2014 to 2018. METHODS Nasopharyngeal swabs were collected from hospitalized children with respiratory symptoms and screened for respiratory pathogens by fluorescence quantitative PCR and culture. The EV-positive samples were subsequently typed by sequencing the 5'-untranslated region and EV-D68-specific VP1 capsid gene. A phylogenetic tree was constructed by the maximum-likelihood method based on the VP1 gene using ClustalW. RESULTS A total of 1,498 (59.8%) out of 2,503 children were screened positive for ≥1 virus species. Among the 158 (6.31%) EV-positive samples, 17 (0.68%) were identified as EV-D68. Most EV-D68 cases (n = 14) were diagnosed with pneumonia and bronchial pneumonia. No deaths were found in EV-D68 cases. Wheezing occurred in EV-D68 cases more frequently (70.59% vs. 43.26%, P = 0.040) than that of other EVs. All the EV-D68 were of clade B3, which were highly similar to the strains circulating in China. CONCLUSION EV-D68 was the predominant enterovirus type in hospitalized children with respiratory symptoms in Guangdong Province. All the EV-D68 strains belong to clade B3. The development of diagnostic tools is warranted in order to monitor EV-D68 infections in China.
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Affiliation(s)
- Shi-Huan Tang
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Ying Yuan
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Zheng-Hua Xie
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Man-Jun Chen
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Xiao-Di Fan
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Yong-Hui Guo
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Meng-Hui Hong
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Shao-Hua Tao
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Nan Yu
- Innovation Platform for Public Health of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China; Department of Medical Laboratory, School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, Guangdong 510515, China.
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Ji MF, Sheng W, Cheng WM, Ng MH, Wu BH, Yu X, Wei KR, Li FG, Lian SF, Wang PP, Quan W, Deng L, Li XH, Liu XD, Xie YL, Huang SJ, Ge SX, Huang SL, Liang XJ, He SM, Huang HW, Xia SL, Ng PS, Chen HL, Xie SH, Liu Q, Hong MH, Ma J, Yuan Y, Xia NS, Zhang J, Cao SM. Incidence and mortality of nasopharyngeal carcinoma: interim analysis of a cluster randomized controlled screening trial (PRO-NPC-001) in southern China. Ann Oncol 2019; 30:1630-1637. [PMID: 31373615 DOI: 10.1093/annonc/mdz231] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [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: 11/13/2022] Open
Abstract
BACKGROUND Previous mass screening studies have shown that IgA antibodies against Epstein-Barr Virus (EBV) can facilitate early detection of nasopharyngeal carcinoma (NPC), but the impact of EBV-antibody screening for NPC-specific mortality remains unknown. PATIENTS AND METHODS A prospective, cluster randomized, controlled trial for NPC screening (PRO-NPC-001) was conducted in 3 selected towns of Zhongshan City and 13 selected towns of Sihui City in southern China beginning in 2008. Serum samples of the screening group were tested for two previously selected anti-EBV antibodies. Subjects with serological medium risk were subsequently retested annually for 3 years, and those with serological high risk were referred to otorhinolaryngologists for diagnostic check-up. An interim analysis was carried out to evaluate the primary end points of the NPC-specific mortality and the early diagnostic rate, and the secondary end point of the NPC incidence, through linkage with the database of Zhongshan City. RESULTS Among 70 296 total subjects, 29 413 screened participants (41.8% of the total subjects) in the screening group and 50 636 in the control group, 153 (43.3 per 100 000 person-year), 62 (55.3 per 100 000 person-year) and 99 (33.1 per 100 000 person-year) NPC cases were identified. The early diagnostic rates of NPC were significantly higher in the participants (79.0%, P < 0.0001) and the screening group (45.9%, P < 0.0001) compared with the control group (20.6%). Although no differences were found between NPC-specific mortality of the screening group and the control group [relative risk (RR)= 0.82, 95% confidence interval (CI) 0.37-1.79], lower NPC-specific mortality was noticed among participants from the screening group versus the control group (RR = 0.22, 95% CI 0.09-0.49). CONCLUSION IgA antibodies against EBV can identify high-risk population and was effective in screening for early asymptomatic NPC. Although the mortality reduction was not significant in the primary end point, we noted encouraging evidence of a mortality reduction in screening participants in this interim analysis. CLINICAL TRIAL NUMBER NCT00941538.
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Affiliation(s)
- M F Ji
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - W Sheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biological Products, School of Public Health, Xiamen University, Xiamen, People's Republic of China
| | - W M Cheng
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - M H Ng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biological Products, School of Public Health, Xiamen University, Xiamen, People's Republic of China
| | - B H Wu
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - X Yu
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - K R Wei
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - F G Li
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - S F Lian
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - P P Wang
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - W Quan
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - L Deng
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - X H Li
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - X D Liu
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - Y L Xie
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - S J Huang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biological Products, School of Public Health, Xiamen University, Xiamen, People's Republic of China
| | - S X Ge
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biological Products, School of Public Health, Xiamen University, Xiamen, People's Republic of China
| | - S L Huang
- Xiaolan Public Health Service Center, Zhongshan, People's Republic of China
| | - X J Liang
- Xiaolan Public Health Service Center, Zhongshan, People's Republic of China
| | - S M He
- Xiaolan People's Hospital of Zhongshan City, Zhongshan, People's Republic of China
| | - H W Huang
- Chen Xinhai Hospital of Xiaolan, Zhongshan, People's Republic of China
| | - S L Xia
- Zhongshan Center for Disease Control and Prevention, Zhongshan, People's Republic of China
| | - P S Ng
- State Key Laboratory for Emerging Infectious Diseases, Department of Microbiology and Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, SAR
| | - H L Chen
- State Key Laboratory for Emerging Infectious Diseases, Department of Microbiology and Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, SAR
| | - S H Xie
- State Key Laboratory of Oncology in Southern China, Department of Epidemiology, Cancer Prevention Center, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China
| | - Q Liu
- State Key Laboratory of Oncology in Southern China, Department of Epidemiology, Cancer Prevention Center, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China
| | - M H Hong
- State Key Laboratory of Oncology in Southern China, Department of Epidemiology, Cancer Prevention Center, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China
| | - J Ma
- State Key Laboratory of Oncology in Southern China, Department of Epidemiology, Cancer Prevention Center, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China
| | - Y Yuan
- Cancer Research Institute of Zhongshan City, Zhongshan Hospital of Sun Yat-sen University, Zhongshan, People's Republic of China
| | - N S Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biological Products, School of Public Health, Xiamen University, Xiamen, People's Republic of China
| | - J Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biological Products, School of Public Health, Xiamen University, Xiamen, People's Republic of China.
| | - S M Cao
- State Key Laboratory of Oncology in Southern China, Department of Epidemiology, Cancer Prevention Center, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China.
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Kim CG, Kim KH, Pyo KH, Xin CF, Hong MH, Ahn BC, Kim Y, Choi SJ, Yoon HI, Lee JG, Lee CY, Park SY, Park SH, Cho BC, Shim HS, Shin EC, Kim HR. Hyperprogressive disease during PD-1/PD-L1 blockade in patients with non-small-cell lung cancer. Ann Oncol 2019; 30:1104-1113. [PMID: 30977778 DOI: 10.1093/annonc/mdz123] [Citation(s) in RCA: 176] [Impact Index Per Article: 35.2] [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: 12/17/2022] Open
Abstract
BACKGROUND Immune checkpoint blockade with Programmed cell death 1 (PD-1)/PD-L1 inhibitors has been effective in various malignancies and is considered as a standard treatment modality for patients with non-small-cell lung cancer (NSCLC). However, emerging evidence show that PD-1/PD-L1 blockade can lead to hyperprogressive disease (HPD), a flair-up of tumor growth linked to dismal prognosis. This study aimed to evaluate the incidence of HPD and identify the determinants associated with HPD in patients with NSCLC treated with PD-1/PD-L1 blockade. PATIENTS AND METHODS We enrolled patients with recurrent and/or metastatic NSCLC treated with PD-1/PD-L1 inhibitors between April 2014 and November 2018. Clinicopathologic variables, dynamics of tumor growth, and treatment outcomes were analyzed in patients with NSCLC who received PD-1/PD-L1 blockade. HPD was defined according to tumor growth kinetics (TGK), tumor growth rate (TGR), and time to treatment failure (TTF). Immunophenotyping of peripheral blood CD8+ T lymphocytes was conducted to explore the potential predictive biomarkers of HPD. RESULTS A total of 263 patients were analyzed. HPD was observed in 55 (20.9%), 54 (20.5%), and 98 (37.3%) patients according to the TGK, TGR, and TTF. HPD meeting both TGK and TGR criteria was associated with worse progression-free survival [hazard ratio (HR) 4.619; 95% confidence interval (CI) 2.868-7.440] and overall survival (HR, 5.079; 95% CI, 3.136-8.226) than progressive disease without HPD. There were no clinicopathologic variables specific for HPD. In the exploratory biomarker analysis with peripheral blood CD8+ T lymphocytes, a lower frequency of effector/memory subsets (CCR7-CD45RA- T cells among the total CD8+ T cells) and a higher frequency of severely exhausted populations (TIGIT+ T cells among PD-1+CD8+ T cells) were associated with HPD and inferior survival rate. CONCLUSION HPD is common in NSCLC patients treated with PD-1/PD-L1 inhibitors. Biomarkers derived from rationally designed analysis may successfully predict HPD and worse outcomes, meriting further investigation of HPD.
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Affiliation(s)
- C G Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon; Division of Medical Oncology, Department of Internal Medicine
| | - K H Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon; Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul
| | - K-H Pyo
- Division of Medical Oncology, Department of Internal Medicine; JE-UK Institute for Cancer Research, JEUK Co. Ltd, Gumi
| | - C-F Xin
- JE-UK Institute for Cancer Research, JEUK Co. Ltd, Gumi
| | - M H Hong
- Division of Medical Oncology, Department of Internal Medicine
| | - B-C Ahn
- Division of Medical Oncology, Department of Internal Medicine
| | - Y Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon
| | - S J Choi
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon
| | - H I Yoon
- Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul
| | - J G Lee
- Department of Thoracic and Cardiovascular Surgery
| | - C Y Lee
- Department of Thoracic and Cardiovascular Surgery
| | - S Y Park
- Department of Thoracic and Cardiovascular Surgery
| | - S-H Park
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon
| | - B C Cho
- Division of Medical Oncology, Department of Internal Medicine
| | - H S Shim
- Department of Pathology, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
| | - E-C Shin
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon.
| | - H R Kim
- Division of Medical Oncology, Department of Internal Medicine.
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Jiaru Z, Guoqing H, Libin L, Yingchun G, Hong MH. Enhancing protein fluorescence detection through hierarchical biometallic surface structuring. Opt Lett 2019; 44:339-342. [PMID: 30644895 DOI: 10.1364/ol.44.000339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 12/05/2018] [Indexed: 06/09/2023]
Abstract
The enhancement of bovine serum albumin (BSA) fluorescence detection using a hierarchical laser-induced periodic surface structure (LIPSS) at the TC4 titanium alloy substrate was experimentally demonstrated. The hierarchical structure, including microgrooves, submicrometer LIPSS, and nanoparticles, has been achieved by a femtosecond laser. Due to the surface plasmon polariton induced by the LIPSS and localized surface plasmon resonance induced by nanoparticles, the enhancement factor of BSA fluorescence detection reached 74. Further, a good linear relationship between the concentration of copper ion inside and BSA fluorescence intensity was found in the range between 5 and 35 μg/mL. Our method explores a simple, reproducible, and pollution-free technique for surface-enhanced fluorescence.
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Kim HR, Kang HN, Shim HS, Kim EY, Kim J, Kim DJ, Lee JG, Lee CY, Hong MH, Kim SM, Kim H, Pyo KH, Yun MR, Park HJ, Han JY, Youn HA, Ahn MJ, Paik S, Kim TM, Cho BC. Co-clinical trials demonstrate predictive biomarkers for dovitinib, an FGFR inhibitor, in lung squamous cell carcinoma. Ann Oncol 2018; 28:1250-1259. [PMID: 28460066 DOI: 10.1093/annonc/mdx098] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Background We conducted co-clinical trials in patient-derived xenograft (PDX) models to identify predictive biomarkers for the multikinase inhibitor dovitinib in lung squamous cell carcinoma (LSCC). Methods The PDX01-02 were established from LSCC patients enrolled in the phase II trial of dovitinib (NCT01861197) and PDX03-05 were established from LSCC patients receiving surgery. These five PDX tumors were subjected to in vivo test of dovitinib efficacy, whole exome sequencing and gene expression profiling. Results The PDX tumors recapitulate histopathological properties and maintain genomic characteristics of originating tumors. Concordant with clinical outcomes of the trial enrolled-LSCC patients, dovitinib produced substantial tumor regression in PDX-01 and PDX-05, whereas it resulted in tumor progression in PDX-02. PDX-03 and -04 also displayed poor antitumor efficacy to dovitinib. Mutational and genome-wide copy number profiles revealed no correlation between genomic alterations of FGFR1-3 and sensitivity to dovitinib. Of note, gene expression profiles revealed differentially expressed genes including FGF3 and FGF19 between PDX-01 and 05 and PDX-02-04. Pathway analysis identified two FGFR signaling-related gene sets, FGFR ligand binding/activation and SHC-mediated cascade pathway were substantially up-regulated in PDX-01 and 05, compared with PDX-02-04. The comparison of gene expression profiles between dovitinib-sensitive versus -resistant lung cancer cell lines in the Cancer Cell Line Encyclopedia database also found that transcriptional activation of 18 key signaling components in FGFR pathways can predict the sensitivity to dovitinib both in cell lines and PDX tumors. These results highlight FGFR pathway activation as a key molecular determinant for sensitivity to dovitinib. Conclusions FGFR gene expression signatures are predictors for the response to dovitinib in LSCC.
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Affiliation(s)
- H R Kim
- Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul
| | - H N Kang
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | | | - E Y Kim
- Pulmonology, Yonsei University College of Medicine, Seoul
| | - J Kim
- Department of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul
| | - D J Kim
- Department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul
| | - J G Lee
- Department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul
| | - C Y Lee
- Department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul
| | - M H Hong
- Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul
| | - S-M Kim
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | - H Kim
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | - K-H Pyo
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | - M R Yun
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | - H J Park
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | - J Y Han
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | - H A Youn
- JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
| | - M-J Ahn
- Division of Hematology & Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - S Paik
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul
| | - T-M Kim
- Department of Medical Informatics, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - B C Cho
- Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul.,JE-UK Institute for Cancer Research, JEUK Co, Ltd, Gumi-City, Kyungbuk
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9
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Yun MR, Choi HM, Kang HN, Lee Y, Joo HS, Kim DH, Kim HR, Hong MH, Yoon SO, Cho BC. ERK-dependent IL-6 autocrine signaling mediates adaptive resistance to pan-PI3K inhibitor BKM120 in head and neck squamous cell carcinoma. Oncogene 2017; 37:377-388. [DOI: 10.1038/onc.2017.339] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Revised: 08/08/2017] [Accepted: 08/12/2017] [Indexed: 02/07/2023]
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10
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Kim HY, Lee YJ, Han BH, Yoon JJ, Ahn YM, Hong MH, Tan R, Kang DG, Lee HS. Mantidis ootheca induces vascular relaxation through PI3K/AKT-mediated nitric oxide-cyclic GMP-protein kinase G signaling in endothelial cells. J Physiol Pharmacol 2017; 68:215-221. [PMID: 28614771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 04/21/2017] [Indexed: 06/07/2023]
Abstract
Mantidis ootheca (Sang Piao Xiao) is well known mantis eggs in a foamy pouch. The purpose of the present study was to investigate the underlying cellular mechanisms of the nitric oxide (NO)-releasing property of the aqueous extract of Mantidis ootheca (AMO) in rat aorta and vascular endothelial cells. AMO was examined for its vascular relaxant effect in isolated phenylephrine-precontracted rat thoracic aortic rings. The roles of the nitric oxide (NO) signaling in the AMO-induced effects were tested in human umbilical vein endothelial cells (HUVECs). HUVEC treated with AMO produced higher amount of NO compared to control. However, AMO-induced increases in NO production were blocked by pretreatment with NG-nitro-L-arginine methylester (L-NAME) or wortmannin. AMO increased in phosphorylation levels of endothelial nitric oxide synthase (eNOS) and Akt in HUVECs, which were attenuated by a NOS and Akt inhibitors. In aortic ring, AMO-induced dose-dependent relaxation of phenylephrine-precontracted aorta was abolished by removal of functional endothelium. Pretreatment with L-NAME, 1H-[1,2,4]-oxadiazolo-[4,3-alpha]-quinoxalin-1-one (ODQ), and KT5823 inhibited the AMO-induced vasorelaxation. Similarly, wortmannin and LY-294002, an inhibitors of the phosphatidylinositol 3-kinase (PI3K), an upstream signaling molecule of eNOS, attenuated the AMO-induced vasorelaxation. Moreover, AMO-induced increases in cGMP production were blocked by pretreatment with L-NAME or ODQ. The vasorelaxant effect of AMO was attenuated by tetraethylammonium, 4-aminopyridine, and glibenclamide. We conclude that AMO relaxed vascular smooth muscle via endothelium-dependent activation of PI3K/Akt-mediated NO-cGMP-PKG signaling pathway and possible involvement of K+ channel.
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Affiliation(s)
- H Y Kim
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
| | - Y J Lee
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
| | - B H Han
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
| | - J J Yoon
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
| | - Y M Ahn
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
| | - M H Hong
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
- Department of Food Industry Convergence, Wonkwang University, Shinyong-dong, Iksan, Korea
| | - R Tan
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
| | - D G Kang
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea.
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea
- Department of Food Industry Convergence, Wonkwang University, Shinyong-dong, Iksan, Korea
| | - H S Lee
- College of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Shinyong-dong, Iksan, Korea
- Hanbang Body-fluid Research Center, Wonkwang University, Shinyong-dong, Ikson, Korea.
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11
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Guan YC, Fang YW, Lim GC, Zheng HY, Hong MH. Fabrication of Laser-reduced Graphene Oxide in Liquid Nitrogen Environment. Sci Rep 2016; 6:28913. [PMID: 27345474 PMCID: PMC4922015 DOI: 10.1038/srep28913] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 06/13/2016] [Indexed: 11/09/2022] Open
Abstract
Porous structure of reduced graphene oxide (rGO) plays an important role in developing flexible graphene-based devices. In this work, we report a novel methodology for reduction of freestanding graphite oxide (GO) sheet by picosecond pulse laser direct writing in liquid nitrogen. Non-agglomerate and porous structure of rGO is fabricated successfully due to frozen effect during laser processing. Compared with laser-irradiated rGO developed in N2 gas at ambient environment, the frozen rGO developed in liquid N2 shows better ordered structure with less defects, crack-free morphology as well as better electron supercapacitor performance including 50–60 Ω/sq in sheet electrical resistance. Mechanism of cryotemperature photoreduction GO is also discussed.
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Affiliation(s)
- Y C Guan
- Beihang University, 37 Xueyuan Road, Beijing, 100191, China.,Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, 638075, Singapore
| | - Y W Fang
- Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, 638075, Singapore
| | - G C Lim
- Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, 638075, Singapore
| | - H Y Zheng
- Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, 638075, Singapore
| | - M H Hong
- National University of Singapore, 4 Engineering Drive 3, 117576, Singapore
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12
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Gao YJ, Zhang BY, Song Q, Wang GJ, Wang WJ, Hong MH, Dou RQ, Sun DL, Zhang QL. Dual-wavelength passively Q-switched Nd:GYSGG laser by tungsten disulfide saturable absorber. Appl Opt 2016; 55:4929-4932. [PMID: 27409120 DOI: 10.1364/ao.55.004929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A dual-wavelength passively Q-switched Nd:GYSGG laser using vacuum evaporating tungsten disulfide (WS2) as a saturable absorber was demonstrated for the first time to the best of our knowledge. The WS2 saturable absorber was prepared simply by evaporating nanometer WS2 powders onto a quartz substrate in a vacuum. By inserting the WS2 saturable absorber into the laser cavity, stable Q-switched laser operation was achieved with a maximum average output power of 367 mW, a pulse repetition rate of 70.7 kHz, the shortest pulse width of 591 ns, and pulse energy of about 1.05 μJ. By vacuum evaporation method, a high-quality WS2 saturable absorber can be produced, and it seems to be a suitable method for fabrication of 2D transition metal dichalcogenides.
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13
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Wu MX, Huang BJ, Chen R, Yang Y, Wu JF, Ji R, Chen XD, Hong MH. Modulation of photonic nanojets generated by microspheres decorated with concentric rings. Opt Express 2015; 23:20096-103. [PMID: 26367667 DOI: 10.1364/oe.23.020096] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A novel design of decorating microsphere surface with concentric rings to modulate the photonic nanojet (PNJ) is investigated. By introducing the concentric ring structures into the illumination side of the microspheres, a reduction of the full width at half maximum (FWHM) intensity of the PNJ by 29.1%, compared to that without the decoration, can be achieved numerically. Key design parameters, such as ring number and depth, are analyzed. Engineered microsphere with four uniformly distributed rings etched at a depth of 1.2 μm and width of 0.25 μm can generate PNJ at a FWHM of 0.485 λ (λ = 400nm). Experiments were carried out by direct observation of the PNJ with an optical microscope under 405 nm laser illumination. As a result, shrinking of PNJ beam size of 28.0% compared to the case without the rings has been achieved experimentally. Sharp FWHM of this design can be beneficial to micro/nanoscale fabrication, optical super-resolution imaging, and sensing.
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14
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Yang J, Li JB, Gong QH, Teng JH, Hong MH. High aspect ratio SiNW arrays with Ag nanoparticles decoration for strong SERS detection. Nanotechnology 2014; 25:465707. [PMID: 25360878 DOI: 10.1088/0957-4484/25/46/465707] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Well-ordered silicon nanowires (SiNWs) are applied as surface-enhanced Raman scattering (SERS) substrates. Laser interference lithography is used to fabricate large-area periodic nanostructures. By controlling the reaction time of metal assisted chemical etching, various aspect ratios of SiNWs are generated. Ag nanoparticles are decorated on the substrates via redox reaction to allow a good coverage of Ag over the SiNWs. As the height of the SiNWs increases, the light scattering inside the structures is enhanced. The number of the probing molecules within the detection volume is increased as well. These factors contribute to stronger light-matter interaction and thus lead to higher SERS signal intensity. However, the light trapping effect is more significant for higher SiNWs, which prevents the detection of the SERS signals. An optimized aspect ratio ∼5:1 (1 μm height and 200 nm width) for the SiNW array is found. The well-ordered SiNWs demonstrate better SERS signal intensity and uniformity than the randomly arranged SiNWs.
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Affiliation(s)
- J Yang
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576. Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research link, Singapore 117602. NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, #02-01, Singapore 117411
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15
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Chen YG, Kao TS, Ng B, Li X, Luo XG, Luk'yanchuk B, Maier SA, Hong MH. Hybrid phase-change plasmonic crystals for active tuning of lattice resonances. Opt Express 2013; 21:13691-13698. [PMID: 23736622 DOI: 10.1364/oe.21.013691] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Tunable lattice resonances are demonstrated in a hybrid plasmonic crystal incorporating the phase-change material Ge2Sb2Te5 (GST) as a 20-nm-thick layer sandwiched between a gold nanodisk array and a quartz substrate. Non-volatile tuning of lattice resonances over a range Δλ of about 500 nm (1.89 µm to 2.27 µm) is achieved experimentally via intermediate phase states of the GST layer. This work demonstrates the efficacy and ease of resonance tuning via GST in the near infrared, suggesting the possibility to design broadband non-volatile tunable devices for optical modulation, switching, sensing and nonlinear optical devices.
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Affiliation(s)
- Y G Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore
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16
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Du ZR, Palina N, Chen J, Aberle AG, Hoex B, Hong MH. Enhancement of laser-induced rear surface spallation by pyramid textured structures on silicon wafer solar cells. Opt Express 2012; 20:A984-A990. [PMID: 23326846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Pulsed laser ablation is increasingly being applied to locally open the rear dielectric layer of advanced silicon wafer solar cell structures, such as aluminum local back surface field solar cells. We report that the laser ablation process on the rear surface of the solar cell at a relatively low laser fluence can cause undesirable spallation at the front surface which is textured with random upright pyramids. This phenomenon is attributed to the enhancement of the surface spallation effect by up to 3 times due to the confinement of the pressure waves at the tips of these random pyramids. Laser ablation at different laser focus positions and laser fluences is carried out to achieve optimized laser processing of the solar cells.
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Affiliation(s)
- Z R Du
- Solar Energy Research Institute of Singapore, National University of Singapore, Building E3A, 7 Engineering Drive 1, 117574 Singapore
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17
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Rao DP, Gu J, Meng XH, Zhang Q, Fu MQ, Liu Y, Chen F, Cao SM, Hong MH, Liu Q. An efficacy analysis for nasopharyngeal carcinoma screening of different screening intervals. J Int Med Res 2012; 40:525-36. [PMID: 22613413 DOI: 10.1177/147323001204000214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE To evaluate the impact of different screening intervals on screening for nasopharyngeal carcinoma (NPC). METHODS A Markov model was constructed, based on the natural history of NPC. The 5-year mortality rate of NPC was the major measurement to evaluate the efficacies of 16 screening strategies. Parameters for the model were derived from published literature. RESULTS Screening reduced the 5-year mortality rate for NPC by 20.4 - 43.3%, compared with the equivalent rate without screening. The 5 year mortality rate and the NPC pick-up rate with strategy A1 (annual screening) were 23.6% and 83.9%, respectively. Compared with strategy A1, strategy B1 (annual screening for seropositive subjects; biennial screening for seronegative subjects) had a similar 5-year mortality rate (24.0%) and a slightly smaller NPC pick-up rate (81.7%), but led to a 39.3% reduction in total screenings. Compared with all other strategies excluding strategy A1, strategy B1 achieved the lowest 5-year mortality rate and the largest NPC pick-up rate. CONCLUSIONS Strategy B1 had the highest efficacy for NPC screening.
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Affiliation(s)
- D P Rao
- Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China
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18
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Ng B, Hanham SM, Giannini V, Chen ZC, Tang M, Liew YF, Klein N, Hong MH, Maier SA. Lattice resonances in antenna arrays for liquid sensing in the terahertz regime. Opt Express 2011; 19:14653-14661. [PMID: 21934827 DOI: 10.1364/oe.19.014653] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Terahertz antenna arrays supporting narrow lattice resonances are proposed as an alternative sensor-on-chip approach to liquid sensing. An array of metallic rectangular antennas fabricated on a polyethylene naphthalate (PEN) substrate is used to demonstrate the sensing of a number of fluids. Good agreement is shown between experiment and simulation with Q-factors of around 20 and a figure-of-merit (FOM) of 3.80 being achieved. Liquid sensing with antenna arrays is simple both in terms of fabrication and setup. The working frequency can be tuned with a suitable choice of substrates and array parameters. The nature of the lattice resonance means that the whole sample is used to provide the conditions required for resonance occurrence, eliminating the need to preferentially locate the sample in small areas of high field concentration. The antenna arrays could also potentially be coupled with a microfluidic system for in situ sensing or used in a reflection setup.
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Affiliation(s)
- B Ng
- Experimental Solid State Goup, Physics Department, Imperial College London, London SW72AZ, UK.
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19
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Rahmani M, Tahmasebi T, Lin Y, Lukiyanchuk B, Liew TYF, Hong MH. Influence of plasmon destructive interferences on optical properties of gold planar quadrumers. Nanotechnology 2011; 22:245204. [PMID: 21543829 DOI: 10.1088/0957-4484/22/24/245204] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Arrays of planar symmetric gold quadrumers consisting of a central nano-disc surrounded by three similar nano-discs belonging to the D(3h) point group were designed and fabricated. Since the geometrical configuration of quadrumers is the same as planar trigonal molecules, nano-discs can play the roles of artificial atoms to study the coupling trends among them. The plasmonic properties of the nano-disc structures are investigated by reflection spectrum measurement and finite-difference time-domain calculation with good agreement. Plasmon interaction among the nano-discs is also studied via a mass-spring coupled oscillator model. A pronounced Fano resonance (FR) is observed for the fabricated nano-discs with inter-disk gaps of around 18 nm during light irradiation at normal incidence. Although the obtained FR is independent of the excitation polarization, the near-field energy spatial distribution can be flexibly tuned by the polarization direction. This has potential applications in nano-lithography, optical switching and nonlinear spectroscopy.
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Affiliation(s)
- M Rahmani
- Data Storage Institute, (A*STAR) Agency for Science, Technology and Research, Singapore
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20
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Han NR, Chen ZC, Lim CS, Ng B, Hong MH. Broadband multi-layer terahertz metamaterials fabrication and characterization on flexible substrates. Opt Express 2011; 19:6990-6998. [PMID: 21503013 DOI: 10.1364/oe.19.006990] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Microscopic split-ring-resonator (SRR) arrays are fabricated on 100 μm thick polyethylene naphthalate (PEN) films by femtosecond laser micro-lens array (MLA) lithography. The transmission properties of these metamaterials are characterized by THz Time Domain Spectroscopy (THz-TDS). Tunable resonance responses can be achieved by changing SRR structural design parameters. By stacking 2D PEN metamaterial films with different frequency responses together, a broadband THz filter with full width at half maximum (FWHM) of 0.38 THz is constructed. The bandwidth of the resonance response increases up to 4.2 times as compared to the bandwidths of single layer metamaterials. Numerical simulation reveals that SRR layers inside the multi-layer metamaterials are selectively excited towards specific frequencies within the broadband response. Meanwhile, more than one SRR layers respond to the chosen frequencies, resulting in the enhancement of the resonance properties. The multi-layer metamaterials provide a promising way to extend SRR based metamaterial operating region from narrowband to broadband with a tunable feature.
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Affiliation(s)
- N R Han
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576, Singapore
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21
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Rahmani M, Lukiyanchuk B, Ng B, Tavakkoli K G A, Liew YF, Hong MH. Generation of pronounced Fano resonances and tuning of subwavelength spatial light distribution in plasmonic pentamers. Opt Express 2011; 19:4949-4956. [PMID: 21445130 DOI: 10.1364/oe.19.004949] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Arrays of plasmonic pentamers consisting of five metallic nano-disks were designed and fabricated to achieve a pronounced Fano Resonance with polarization-independent far-field spectral response at normal incidence due to the structure symmetry of pentamers. A mass-spring coupled oscillator model was applied to study plasmon interactions among the nano-disks. It was found that the direction of the excitation light polarization can flexibly tune the spatial localization of near-field energy at sub-wavelength scales while the collective optical properties are kept constant. It can lead to a selective storage of excited energy down to sub-20 nm gap at a normal incident with a single light source.
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Affiliation(s)
- M Rahmani
- Data Storage Institute, (A*STAR) Agency for Science Technology and Research, 5 Engineering Drive 1, 117608 Singapore
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22
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Yun J, Wang R, Hong MH, Thong JTL, Foo YL, Thompson CV, Choi WK. Converting carbon nanofibers to carbon nanoneedles: catalyst splitting and reverse motion. Nanoscale 2010; 2:2180-2185. [PMID: 20697651 DOI: 10.1039/c0nr00265h] [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: 05/29/2023]
Abstract
Carbon nanoneedles (CNNs) were grown using a plasma-enhanced chemical vapor deposition process in which the source gas (C(2)H(2)) was turned off 10 min before the NH(3) flow and plasma were turned off. It is demonstrated that tubular carbon nanofibers (CNFs) grow while the source gas is on. However, once the source gas is turned off, the Ni catalyst at the top of each CNF splits to form a small catalyst that remains at the top of the tube and a larger catalyst that travels down the interior of the tube. We postulate that the motion of the bottom (larger) catalyst is driven by etching of the graphitic walls and 'cups' inside the CNF. This process, combined with slowing growth of the CNFs and etching of the material above the bottom catalyst, converts the carbon nanofibers to the final nanoneedle shape.
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Affiliation(s)
- Jia Yun
- Advanced Materials for Micro- and Nano-Systems Programme, Singapore-MIT Alliance, Singapore
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23
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Lim CS, Hong MH, Chen ZC, Han NR, Luk'yanchuk B, Chong TC. Hybrid metamaterial design and fabrication for terahertz resonance response enhancement. Opt Express 2010; 18:12421-12429. [PMID: 20588369 DOI: 10.1364/oe.18.012421] [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: 05/29/2023]
Abstract
Planar hybrid metamaterial with different split ring resonators (SRR) structure dimensions are fabricated on silicon substrates by femtosecond (fs) laser micro-lens array (MLA) lithography and lift-off process. The fabricated metamaterial structures consist of: (a) uniform metamaterial with 4 SRRs at same design and dimension as a unit cell and (b) hybrid metamaterial with 4 SRRs at same design but different dimensions as a unit cell. The electromagnetic field responses of these hybrid and single dimension metamaterial structures are characterized using a terahertz (THz) time-domain spectroscopy. Transmission spectra of these metamaterial show that a broader resonance peak is formed when 2 SRRs are close to each other. FDTD simulation proves that there is a strong mutual coupling between 2 SRRs besides a strong localized electric field at the split gap, which can enhance the electric field up to 364 times for tunable, broad band and high sensitivity THz sensing. Meanwhile, the strong coupling effect could lead to the formation of an additional resonance peak at approximately 0.2 THz in the THz spectra regime.
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Affiliation(s)
- C S Lim
- Data Storage Institute, 5 Engineering Drive 1, 117608 Singapore
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Dawood MK, Liew TH, Lianto P, Hong MH, Tripathy S, Thong JTL, Choi WK. Interference lithographically defined and catalytically etched, large-area silicon nanocones from nanowires. Nanotechnology 2010; 21:205305. [PMID: 20418606 DOI: 10.1088/0957-4484/21/20/205305] [Citation(s) in RCA: 11] [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: 05/25/2023]
Abstract
We report a simple and cost effective method for the synthesis of large-area, precisely located silicon nanocones from nanowires. The nanowires were obtained from our interference lithography and catalytic etching (IL-CE) method. We found that porous silicon was formed near the Au catalyst during the fabrication of the nanowires. The porous silicon exhibited enhanced oxidation ability when exposed to atmospheric conditions or in wet oxidation ambient. Very well located nanocones with uniform sharpness resulted when these oxidized nanowires were etched in 10% HF. Nanocones of different heights were obtained by varying the doping concentration of the silicon wafers. We believe this is a novel method of producing large-area, low cost, well defined nanocones from nanowires both in terms of the control of location and shape of the nanocones. A wide range of potential applications of the nanocone array can be found as a master copy for nanoimprinted polymer substrates for possible biomedical research; as a candidate for making sharp probes for scanning probe nanolithography; or as a building block for field emitting tips or photodetectors in electronic/optoelectronic applications.
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Affiliation(s)
- M K Dawood
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576 Singapore
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25
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Wang ZB, Guo W, Pena A, Whitehead DJ, Luk'yanchuk BS, Li L, Liu Z, Zhou Y, Hong MH. Laser micro/nano fabrication in glass with tunable-focus particle lens array. Opt Express 2008; 16:19706-19711. [PMID: 19030056 DOI: 10.1364/oe.16.019706] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Based on medium-tuned optical field enhancement effect around a self-assembled particle-lens array (PLA) irradiated with a femtosecond (fs) laser source, we demonstrated that high-precision periodical array of micro/nano-structures can be readily fabricated on glass surface or inside glass in large areas in parallel without any cracks or debris. The technique has potential for rapid fabrication of three-dimensional structures in multiple layers inside glass.
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Affiliation(s)
- Z B Wang
- Laser Processing Research Centre, School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Sackville Street, Manchester, M60 1QD, United Kingdom.
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26
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Choi WK, Liew TH, Dawood MK, Smith HI, Thompson CV, Hong MH. Synthesis of silicon nanowires and nanofin arrays using interference lithography and catalytic etching. Nano Lett 2008; 8:3799-802. [PMID: 18954118 DOI: 10.1021/nl802129f] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We report results on the synthesis of silicon nanostructures that were fabricated using a combination of interference lithography and catalytic etching. With this technique, we were able to create nanostructures that are perfectly periodic over very large areas (1 cm(2) or more), where the cross-sectional shapes and the array ordering can be varied. Furthermore this technique can readily and independently control the sizes and spacings of the nanostructures down to spacings of 200 nm or less. These characteristics cannot be achieved using other known techniques.
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Affiliation(s)
- W K Choi
- Advanced Materials for Micro- and Nano-Systems Programme, Singapore-MIT Alliance, Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576.
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Lai WJ, Lim BC, Phua PB, Tiaw KS, Teo HH, Hong MH. Generation of radially polarized beam with a segmented spiral varying retarder. Opt Express 2008; 16:15694-15699. [PMID: 18825207 DOI: 10.1364/oe.16.015694] [Citation(s) in RCA: 8] [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: 05/26/2023]
Abstract
We convert a linearly polarized Gaussian beam into a radially polarized doughnut beam with an eight-segment spirally varying retarder (SVR) at wavelength of 808 nm. The SVR is designed based on the linear birefringence of alpha-barium borate (alpha-BBO) crystal and fabricated using a dry etching process. Radially polarized light of high purity (> 96% at far-field distribution) was generated experimentally using the segmented SVR positioned between two quarter waveplates with orthogonal slow axes. The emergent polarization can be switched between radially and azimuthally polarized cylindrical vector beams with a pair of half-wave plates.
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Affiliation(s)
- W J Lai
- Temasek Laboratories, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553
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28
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Margueritat J, Gonzalo J, Afonso CN, Hörmann U, Van Tendeloo G, Mlayah A, Murray DB, Saviot L, Zhou Y, Hong MH, Luk'yanchuk BS. Surface enhanced Raman scattering of silver sensitized cobalt nanoparticles in metal-dielectric nanocomposites. Nanotechnology 2008; 19:375701. [PMID: 21832555 DOI: 10.1088/0957-4484/19/37/375701] [Citation(s) in RCA: 4] [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] [Indexed: 05/31/2023]
Abstract
We report the preparation of a new type of nanocomposite containing cobalt and silver nanoparticles organized in parallel layers with a well controlled separation. This arrangement allows the observation of an enhanced low-frequency Raman signal at the vibration frequency of cobalt nanoparticles excited through the surface plasmons of silver nanoparticles. Numerical simulations of the electric field confirm the emergence of hot spots when the separation between silver and cobalt nanoparticles is small enough.
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Affiliation(s)
- J Margueritat
- Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid, Spain. Centre d'Elaboration de Matériaux et d'Etudes Structurales CNRS/Université Paul Sabatier, 29, rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4, France
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29
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Liu CH, Hong MH, Cheung HW, Zhang F, Huang ZQ, Tan LS, Hor TSA. Bimetallic structure fabricated by laser interference lithography for tuning surface plasmon resonance. Opt Express 2008; 16:10701-10709. [PMID: 18607486 DOI: 10.1364/oe.16.010701] [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: 05/26/2023]
Abstract
Tuning of surface plasmon resonance by gold and silver bimetallic thin film and bimetallic dot array is investigated. Laser interference lithography is applied to fabricate the nanostructures. A bimetallic dot structure is obtained by a lift-off procedure after gold and silver thin film deposition by an electron beam evaporator. Surface plasmon behaviors of these films and nanostructures are studied using UV-Vis spectroscopy. It is observed that for gold thin film on quartz substrate, the optical spectral peak is blue shifted when a silver thin film is coated over it. Compared to the plasmon band in single metal gold dot array, the bimetallic nanodot array shows a similar blue shift in its spectral peak. These shifts are both attributed to the interaction between gold and silver atoms. Electromagnetic interaction between gold and silver nanostructures is discussed using a simplified spring model.
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Affiliation(s)
- C H Liu
- Department of Electrical and Computer Engineering, 4 Engineering Drive 3, Singapore 117576
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Teo SHG, Liu AQ, Zhang JB, Hong MH, Singh J, Yu MB, Singh N, Lo GQ. Photonic bandgap crystal resonator enhanced, laser controlled modulations of optical interconnects for photonic integrated circuits. Opt Express 2008; 16:7842-7848. [PMID: 18545494 DOI: 10.1364/oe.16.007842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Ultrafast high-density photonic integrated circuit devices (PICDs) are not easily obtained using traditional index-guiding mechanisms. In this paper, photonic bandgap crystal resonator enhanced, laser-controlled modulations of optical interconnect PICDs were achieved in slab-type mix-guiding configuration - through developed CMOS-compatible processing technologies. The devices, with smallest critical dimensions of 90 nm have footprints of less than 5 x 5 microm(2). Quality-factors an order larger than previously realized was achieved. Through use of effective coupling structures; simultaneous alignment for probing and pumping laser beams, optical measurements of both instantaneous free carriers induced device modulations were obtained together with thermo-optical effects characterizations.
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Affiliation(s)
- Selin H G Teo
- Institute of Microelectronics, 11 Science Park Road, Singapore.
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31
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Abstract
A fast and switchable electro-optic radial polarization retarder (EO-RPR) fabricated using the electro-optic ceramic Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) is presented. This EO-RPR is useful for fast and switchable generation of a pure cylindrical vector beam. When used together with a pair of half-wave plates, the EO-RPR can change circularly polarized light into any cylindrical vector beam of interest, such as radially or azimuthally polarized light. Radially and azimuthally polarized light with purities greater than 95% are generated experimentally. The advantages of using EO-RPR include fast response time, low driving voltage, and transparency in a wide spectral range (500 to 7,000 nm).
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Affiliation(s)
- B C Lim
- Data Storage Institute, DSI Building, 5, Engineering Drive 1, Singapore 117608
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Luk‘yanchuk BS, Tribelsky MI, Ternovsky V, Wang ZB, Hong MH, Shi LP, Chong TC. Peculiarities of light scattering by nanoparticles and nanowires near plasmon resonance frequencies in weakly dissipating materials. ACTA ACUST UNITED AC 2007. [DOI: 10.1088/1464-4258/9/9/s03] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lukyanchuk BS, Wang ZB, Tribelsky M, Ternovsky V, Hong MH, Chong TC. Peculiarities of light scattering by nanoparticles and nanowires near plasmon resonance frequencies. ACTA ACUST UNITED AC 2007. [DOI: 10.1088/1742-6596/59/1/050] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Phua PB, Lai WJ, Lim YL, Tiaw KS, Lim BC, Teo HH, Hong MH. Mimicking optical activity for generating radially polarized light. Opt Lett 2007; 32:376-8. [PMID: 17356658 DOI: 10.1364/ol.32.000376] [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: 05/14/2023]
Abstract
We propose a new scheme for generating radially polarized light by mimicking optical activity using linear birefringence. It involves a birefringent spirally varying retarder sandwiched between two orthogonally oriented quarter-wave plates. Using Poincaré sphere representation, we show that the polarization transformation of such a scheme is equivalent to that of a spirally varying optical activity and is capable of generating radially polarized light. We demonstrate the proof-of-concept using y-cut crystalline quartz.
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Affiliation(s)
- P B Phua
- DSO National Laboratories, Singapore.
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35
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Sunwoo S, Kim YS, Cho BL, Cheon KS, Seo HG, Rho MK, Cheong YS, Hong MH, Kim SW, Kim DH. Post-marketing surveillance study of the safety and efficacy of sildenafil prescribed in primary care to erectile dysfunction patients. Int J Impot Res 2005; 17:71-5. [PMID: 15510193 DOI: 10.1038/sj.ijir.3901263] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In order to investigate the safety and efficacy of sildenafil prescribed in primary care, a post-marketing surveillance study was undertaken. A total of 651 men with erectile dysfunction (ED) were enrolled from 31 family physicians in Korea from December 1999 to July 2002. Patients were regularly followed up to ascertain the safety and efficacy of sildenafil. Of the 651 patients enrolled, 572 (87.9%) returned for safety evaluation and efficacy assessment. In all, 458 (80.1%) of 572 patients reported improved erectile function with sildenafil. Hypertension, diabetes and low-dose sildenafil were associated with poor efficacy. A total of 71 adverse events were reported among 56 patients (8.6%), with the most frequent being hot flushes (5.6%), followed by headache (2.6%), palpitation (1.0%), anxiety (0.5%) and elevated ALT (0.5%). Only six patients (1.0%) discontinued sildenafil as a direct result of adverse events. These results suggest that sildenafil prescribed by primary care physicians was well tolerated and improved erectile function in patients with ED.
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Affiliation(s)
- S Sunwoo
- Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, Seoul, Republic of Korea
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Kim OT, Kim MY, Hong MH, Ahn JC, Hwang B. Stimulation of asiaticoside accumulation in the whole plant cultures of Centella asiatica (L.) urban by elicitors. Plant Cell Rep 2004; 23:339-344. [PMID: 15316748 DOI: 10.1007/s00299-004-0826-7] [Citation(s) in RCA: 31] [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] [Received: 10/20/2003] [Revised: 05/25/2004] [Accepted: 05/26/2004] [Indexed: 05/24/2023]
Abstract
The effects of a number of different elicitors on asiaticoside production in whole plant cultures of Centella asiatica were studied, including yeast extract, CdCl(2), CuCl(2) and methyl jasmonate (MJ). Only MJ and yeast extract stimulated asiaticoside production--1.53 and 1.41-fold, respectively. Maximum asiaticoside production was achieved following treatment with 0.1 mM MJ (116.8 mg/l). The highest asiaticoside production (342.72 mg/l) was obtained after 36 days of elicitation in cultures treated with 0.1 mM MJ and 0.025 mg/l 1-phenyl-3-(1,2,3-thidiazol-5-yl)urea (TDZ). Interestingly, MJ not only stimulated the production of asiaticoside but also had an important role in the senescence of C. asiatica. Although asiaticoside content did not change when TDZ was added to medium containing an elicitor, TDZ did increase shoot growth of C. asiatica. We discuss the interactive roles of MJ and TDZ in secondary metabolic production and biomass in whole plants of C. asiatica.
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Affiliation(s)
- O T Kim
- Department of Biology, Chonnam National University, Gwangju, 500-757, South Korea
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37
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Cho BL, Kim YS, Choi YS, Hong MH, Seo HG, Lee SY, Shin HC, Kim CH, Moon YS, Cha HS, Kim BS. Prevalence and risk factors for erectile dysfuntion in primary care: results of a Korean study. Int J Impot Res 2003; 15:323-8. [PMID: 14562132 DOI: 10.1038/sj.ijir.3901022] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [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: 01/23/2023]
Abstract
In order to assess the prevalence and associated factors for erectile dysfunction (ED) in primary care, a cross-sectional study was undertaken by questionnaire distributed to consecutive adult male attendees at 32 family practices. ED was assessed by the Korean five-item version of the International Index of Erectile Function (IIEF-5). In total, 3501 completed questionnaires were available for analysis. The prevalence of ED was severe (IIEF-5 score: 5-9) in 1.6% of cases, moderate (10-13) in 10.2%, mild (14-17) in 24.7%, and normal (18-25) in 63.4%. The prevalence of ED increased with age, lower educational status, heavy job-related physical activity, and lower income. ED prevalence was significantly higher in patients with chronic diseases such as diabetes, depression, and anxiety. These results suggest that the age-adjusted prevalence of ED among Korean men can be estimated as 32.2% (95% CI 30.6-33.7). Low socioeconomic status and several diseases such as diabetes, anxiety, and depression, as well as age, were associated with ED.
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Affiliation(s)
- B L Cho
- Seoul National University College of Medicine, Seoul, Republic of Korea
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38
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Affiliation(s)
- N Bityurin
- Institute of Applied Physics Russian Academy of Sciences, 603950, Nizhnii Novgorod, Russia.
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39
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Ma J, Mai HQ, Hong MH, Cui NJ, Lu TX, Lu LX, Mo HY, Min HQ. Is the 1997 AJCC staging system for nasopharyngeal carcinoma prognostically useful for Chinese patient populations? Int J Radiat Oncol Biol Phys 2001; 50:1181-9. [PMID: 11483327 DOI: 10.1016/s0360-3016(01)01537-1] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [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: 10/18/2022]
Abstract
PURPOSE The 5th edition of the American Joint Committee on Cancer (AJCC) staging manual defines new rules for classifying nasopharyngeal carcinoma (NPC). The study was conducted to assess its effectiveness in predicting the prognosis for Chinese patient populations. METHODS AND MATERIALS Between June 1993 and June 1994, 621 consecutively admitted patients with nondisseminated NPC were treated with definitive-intent radiation therapy alone. All had computed tomography of the nasopharynx, skull base, and the upper neck. A computer database containing all information for staging was formed on presentation. The extent of disease of each patient was restaged according to the 1997 AJCC system. RESULTS Of the 621 patients, The 5-year overall survival (OS) rate was 60%. The 1997 AJCC system creates subgroups (Stages I to IV) that are assigned to 38 (6.1%), 270 (43.5%), 157 (25.3%), and 156 (25.1%) patients, respectively. The incidence of parapharyngeal extension was 74.1% (460/621). Of these patients (460) with parapharyngeal extension, 310 (67.4%) patients were classified as T2b disease. The 1997 AJCC system showed highly significant differences between the overall stages for both OS and relapse-free survival (RFS). The 1997 AJCC T classifications showed significant correlation with local failure, and N classification was accurate in predicting FDM. Multivariate analysis showed that paraoropharyngeal involvement was an independently significant prognostic factor for OS, freedom from local recurrence (FLR), and freedom form distant metastasis (FDM). CONCLUSION The 1997 AJCC staging system for NPC is prognostically useful for Chinese patient populations. We proposed that subdivision of parapharyngeal extension should be included in future revisions of the staging system.
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Affiliation(s)
- J Ma
- Department of Nasopharyngeal Carcinoma, Cancer Center, Sun Yat-sen University of Medical Sciences, Guangzhou, People's Republic of China.
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Ma J, Mai HQ, Hong MH, Min HQ, Mao ZD, Cui NJ, Lu TX, Mo HY. Results of a prospective randomized trial comparing neoadjuvant chemotherapy plus radiotherapy with radiotherapy alone in patients with locoregionally advanced nasopharyngeal carcinoma. J Clin Oncol 2001; 19:1350-7. [PMID: 11230478 DOI: 10.1200/jco.2001.19.5.1350] [Citation(s) in RCA: 292] [Impact Index Per Article: 12.7] [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: 11/20/2022] Open
Abstract
PURPOSE A prospective randomized trial was performed to evaluate the contribution of neoadjuvant chemotherapy in patients with locoregionally advanced nasopharyngeal carcinoma. PATIENTS AND METHODS Patients with locoregionally advanced nasopharyngeal carcinoma were treated either with radiotherapy alone (RT group) or neoadjuvant chemotherapy plus radiotherapy (CT/RT group). Neoadjuvant chemotherapy consisting of two to three cycles of cisplatin (100 mg/m(2), day 1), bleomycin (10 mg/m(2), days 1 and 5), and fluorouracil (5-FU; 800 mg/m(2), days 1 through 5, continuous infusion) followed by radiotherapy was given to the CT/RT group. All patients were treated in a uniform fashion by definitive-intent radiation therapy in both groups. RESULTS Between July 1993 and July 1994, 456 patients were entered onto the study, with 228 patients randomized to each treatment arm, and 449 patients (225 in the RT group and 224 in the CT/RT group) were assessable. All 456 patients were included in survival analysis according to the intent-to-treat principle. The 5-year overall survival (OS) rates were 63% for the CT/RT group and 56% for the RT group (P =.11). The median relapse-free survival (RFS) time was 50 months for the RT group and not reached for the CT/RT group. The 5-year RFS rate was 49% for the RT group versus 59% for the CT/RT group (P =.05). The 5-year freedom from local recurrence rate was 82% for the CT/RT group and 74% for the RT group (P =.04). There was no significant difference in freedom from distant metastasis between the two treatment groups (CT/RT group, 79%; RT group, 75%; P =.40). CONCLUSION This randomized study failed to demonstrate any significant survival benefit with the addition of neoadjuvant chemotherapy for patients with locoregionally advanced nasopharyngeal carcinoma. Therefore, neoadjuvant chemotherapy for nasopharyngeal carcinoma should not be used outside of the context of a clinical trial.
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Affiliation(s)
- J Ma
- Department of Nasopharyngeal Carcinoma, Cancer Center, Sun Yat-sen University of Medical Sciences, Guangzhou, People's Republic of China.
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41
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Bae JH, Kim KH, Hong MH, Gim CH, Jhe W. High-resolution confocal detection of nanometric displacement by use of a 2 x 1 optical fiber coupler. Opt Lett 2000; 25:1696-1698. [PMID: 18066317 DOI: 10.1364/ol.25.001696] [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: 05/25/2023]
Abstract
A novel high-resolution confocal measurement of nanometric displacement that uses a simple 2 x 1 optical fiber coupler is presented. The basic principle is to detect interferometrically the change in the phase difference between two adjacent input fibers of the coupler that results from the nonuniform wave-front curvature of the reflected light. Measurement of subnanometer axial modulation, which permits high-resolution displacement sensing by optical means, is demonstrated.
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Affiliation(s)
- J H Bae
- Center for Near-Field Atom-Photon Technology and Department of Physics, Seoul National University, Seoul 151-742, Korea
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42
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Hong MH, Mai HQ, Min HQ, Ma J, Zhang EP, Cui NJ. A comparison of the Chinese 1992 and fifth-edition International Union Against Cancer staging systems for staging nasopharyngeal carcinoma. Cancer 2000; 89:242-7. [PMID: 10918151 DOI: 10.1002/1097-0142(20000715)89:2<242::aid-cncr6>3.0.co;2-z] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND The Chinese 1992 staging system for nasopharyngeal carcinoma (NPC) has been widely adopted in mainland China since 1992. The fifth edition of the International Union Against Cancer (UICC) TNM classification defines new rules for classifying NPC. The current study compares the two in predicting NPC prognosis. METHODS Four hundred eleven NPC patients, most of whom had disease of undifferentiated histologic type and were treated in a constant fashion and with definitive intent with radiation therapy alone, entered this comparative study. The patients were restaged according to the rules of the fifth edition of the UICC staging manual and the Chinese 1992 staging system. RESULTS In the opinion of the authors, the predictive power of the Chinese 1992 T classification was superior. Conversely, the authors felt that the UICC N classification was more reasonable. The patients were categorized more evenly by the UICC stages than by the Chinese 1992 stages. The 5-year disease specific survival rates for patients in corresponding stages of both systems were almost identical despite differences in the criteria defining T and N classifications. Statistical analysis showed that the agreement rate was 72%. There were some agreement and correlation between the two staging systems. CONCLUSIONS Both systems are essentially similar. Each system appears to have some subtleties that could improve the outcome prediction of the other system if the two were somehow combined. However, it appeared to the authors that the UICC system was slightly better.
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Affiliation(s)
- M H Hong
- Department of Nasopharyngeal Carcinoma, Cancer Center, Sun Yat-sen University of Medical Sciences, Guangzhou, People's Republic of China
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Qian CN, Min HQ, Lin HL, Hong MH. Combination of angiogenesis inhibitor TNP-470 with cytotoxic drugs in experimental therapy of nasopharyngeal carcinoma. Ann Otol Rhinol Laryngol 2000; 109:641-5. [PMID: 10903044 DOI: 10.1177/000348940010900705] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study was conducted to evaluate the effectiveness of angiogenesis inhibitor 6-O-(N-chloroacetyl-carbamoyl)-fumagillol (TNP-470. AGM-1470) in the treatment of nasopharyngeal carcinoma (NPC) alone and in combination with cytotoxic agents. Forty-two male BALB/c nude mice bearing human NPC cell line CNE-2 were randomized into 6 groups: those treated with saline solution, TNP-470, cisplatin (DDP), fluorouracil (5-FU), TNP-470 + DDP, and TNP-470 + 5-FU, respectively. In every treatment group, tumor growth was suppressed significantly. The combination of 5-FU with TNP-470 showed significant enhancement in antitumor efficacy. TNP-470 also enhanced the inhibitory effect of DDP, although not to statistical significance. All animals gained in body weight, although treatment with 5-FU caused slight, reversible diarrhea of 2 to 3 days' duration. The results showed that TNP-470 suppressed the growth of the human NPC cell line and enhanced the antitumor effect of 5-FU without increasing its toxicity. The combination of angiogenesis inhibitors with conventional cytotoxic agents is promising in the treatment of NPC.
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Affiliation(s)
- C N Qian
- Department of Nasopharyngeal Carcinoma, Cancer Center, Sun Yat-sen University of Medical Sciences, Guangzhou, People's Republic of China
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Abstract
Interleukin-10 (IL-10) inhibits osteoclast (OC) formation in rat and mouse systems. However, little is known concerning the mechanism of this inhibitory effect. Using a coculture system of mouse bone marrow cells and primary osteoblastic cells (POB), we evaluated the potential target cells for IL-10 and components of the IL-10 activating pathway. In the coculture system, IL-10 treatment abolished OC differentiation in a dose-dependent manner. This inhibitory effect occurred regardless of the stage of cellular proliferation and differentiation, suggesting that IL-10 may act on a variety of genes participating in OC formation. IL-10 specifically abrogated the production of IL-6 by enriched bone marrow-derived mononuclear cells (BMM) but not by osteoblastic cells. IL-10 treatment also stimulated the binding of a protein in the BMM to an IL-10 response element, whereas no such activation was induced in osteoblastic cells. In contrast, interferon gamma (IFN-gamma), another inhibitory factor, stimulated tyrosine-phosphorylated proteins to bind to an IL-10 response element in both monocytes and osteoblastic cells. These data suggest that the BMM are the direct target of IL-10 action. Importantly, oligonucleotide-specific precipitation confirmed that IL-10 treatment strongly augmented 88, 85, and 70 kDa tyrosine-phosphorylated proteins in BMM. Taken together, these data show that IL-10 inhibits mouse OC formation by acting directly on hemopoietic OC precursor, through a novel signal transduction and activation pathway.
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Affiliation(s)
- M H Hong
- Department of Endocrine Research, Ligand Pharmaceuticals, Inc., San Diego, California 92121, USA
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Qian CN, Zhang CQ, Guo X, Hong MH, Cao SM, Mai WY, Min HQ, Zeng YX. Elevation of serum vascular endothelial growth factor in male patients with metastatic nasopharyngeal carcinoma. Cancer 2000; 88:255-61. [PMID: 10640954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
BACKGROUND Angiogenesis is essential for tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is the most potent angiogenic factor identified to date. The authors investigated the correlation between the levels of serum VEGF (S-VEGF) in patients with nasopharyngeal carcinoma (NPC) and disease progression. METHODS The sera from 65 male patients with nonmetastatic NPC, 22 male patients with metastatic NPC, and 27 healthy male volunteers were obtained. A quantitative enzyme-linked immunosorbent assay was performed to measure the concentrations of S-VEGF in the sera. RESULTS The mean S-VEGF levels were 371.0 pg/mL(-1) (range, 128.5-691.1 pg/mL(-1)) for healthy controls, 375.6 pg/mL(-1) (range, 72.9-1202.5 pg/mL(-1)) for patients with nonmetastatic NPC, and 958.6 pg/mL(-1) (range, 264.4-3744.9 pg/mL(-1)) for patients with metastatic NPC. The mean S-VEGF level in patients with metastatic NPC was significantly higher than in either patients with nonmetastatic NPC (P < 0.001) or healthy controls (P < 0.001). However, there was no statistical difference between these results for healthy controls and patients with nonmetastatic NPC. At the level of 900 pg/mL(-1), S-VEGF indicated distant dissemination of NPC with a specificity of 95.4%, a sensitivity of 31.8%, a positive predictive value of 70.0%, and a negative predictive value of 80.5%. No significant differences in the levels of S-VEGF were found among various T classifications, N classifications, and clinical stages of nonmetastatic NPC. CONCLUSIONS The levels of S-VEGF were significantly elevated in male patients with metastatic NPC. These levels did not correlate with locoregional progression of NPC. The usefulness of detecting S-VEGF in the early diagnosis of NPC appears to be limited.
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Affiliation(s)
- C N Qian
- Department of Nasopharyngeal Carcinoma, Cancer Center, Sun Yat-sen University of Medical Sciences, Guangzhou, People's Republic of China
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Abstract
OBJECTIVES (i) To examine the components of variation in nutrient intakes for older Korean adults; (ii) To calculate the level of accuracy with varying degree of precision in order to achieve estimates of usual nutrient intakes. DESIGN Five or six 24 h recalls were made over a four month period on each individual. SETTING A senior school from a middle-income, urban community in Inchon, Korea. SUBJECTS Forty-seven males and 36 females over 60 y old with complete records for at least five dietary recalls. RESULTS The within-person variation of nutrient intakes (21.8-103.2%) was higher and differed more markedly by nutrients than the between-person variation (9.4-63.7%). Males (2.26-11.28) showed larger within-to-between person variance ratios than females (1.73-5.86). The variance ratios were different by nutrients for males, but no such pattern was observed for females. Depending on nutrients, 5-6 recalls over a four month period gave estimates of nutrient intakes within 30-50% of usual intakes. For most nutrients, 100-200 subjects were sufficient to obtain estimates with 10% deviation of group usual intakes. Achieving r=0.9 between observed and usual intakes required 24-54 recalls for males and 8-23 recalls for females. CONCLUSIONS The degree of precision achieved during assessment of older Korean adults' usual nutrient intakes changes with gender and by the type of nutrients. Achieving similar level of accuracy of the estimates, older Korean adults may require more dietary recalls than the adults in western countries.
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Affiliation(s)
- S Y Oh
- Department of Food and Nutrition, Kyung Hee University, Seoul, Korea
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Qian CN, Min HQ, Lin HL, Hong MH, Ye YL. Primary study in experimental antiangiogenic therapy of nasopharyngeal carcinoma with AGM-1470 (TNP-470). J Laryngol Otol 1998; 112:849-53. [PMID: 9876375 DOI: 10.1017/s0022215100141878] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [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: 11/05/2022]
Abstract
OBJECTIVE To evaluate the efficacy of the angiogenesis inhibitor AGM-1470 for the experimental treatment of nasopharyngeal carcinoma (NPC). METHODS A NPC human tumour model was built by tumour-bearing nude mice using the NPC cell line CNE-2. Twenty-one BALB/c nude mice bearing CNE-2 xenografts were randomized into a treatment group and a control group. In the treatment group, AGM-1470 was injected 30 mg/kg subcutaneously every other day; while the vehicle (three per cent ethanol solution in 0.9 per cent saline) was given to the mice in control group. Tumour volumes and animal weights were measured every third day. Autopsy was performed after 18 days of treatment. The tumour tissue as well as the murine tissues of heart, kidney, and liver in each mouse were removed for formalin fixation and routine HE staining. Pathological evaluation was performed in these tissues. RESULTS There was a significant difference in tumour volume between the two groups at day 9 of treatment and this increased thereafter. At day 15 of treatment, the tumour volume was 4251 +/- 559 mm3 (n = 10) in the control group versus 3122 +/- 967 mm3 (n = 11) in the AGM-1470 treated group (p = 0.004); and T:C ratio (mean tumour volume of treated/mean tumour volume of control) was 0.73, resulting in a 27 per cent decrease in tumour growth. Central necrosis and consequential shrinkage of tumours occurred in both groups at the end of experiment. Physical toxicity and histological toxicity of heart, liver, and kidney did not result from AGM-1470 therapy. CONCLUSIONS AGM-1470 suppresses the growth of the human NPC cell line CNE-2. Treatment by AGM-1470 has no physical nor histological toxicity. Angiogenesis inhibitors may be effective in the treatment of the local lesion of NPC.
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Affiliation(s)
- C N Qian
- Department of Nasopharyngeal Carcinoma, Tumor Hospital, Sun Yat-sen University of Medical Sciences, (SUMS), Guangzhou, P.R. of China.
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Pang WW, Huang S, Chung YT, Chang DP, Lin SS, Hong MH. Comparison of intravenous retention of fentanyl and lidocaine on local analgesia in propofol injection pain. Acta Anaesthesiol Sin 1997; 35:217-21. [PMID: 9553237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND With a tourniquet on arm for arresting venous blood flow, we evaluated the efficacy of intravenous (i.v.) retention of fentanyl and lidocaine in reducing the pain on i.v. propofol injection during general anesthesia. METHODS One hundred and twelve patients were studied. Following a venous occlusion by a tourniquet inflated to 70 mmHg, patients in Group A (n = 38) received normal saline (NS) 3 ml, while those in Group B (n = 37) and in Group C (n = 37) respectively received fentanyl 150 micrograms or 3 ml and 2% lidocaine 3 ml (60 mg). The venous retention of drug was maintained for 1 min, followed immediately by tourniquet release and propofol 100 mg i.v. injection over 20 s. RESULTS Both fentanyl and lidocaine treatments (Groups B and C) were significantly better than placebo (Group A) in reducing pain on propofol injection (p < 0.005). Lidocaine 60 mg was more effective than fentanyl 150 micrograms in reduction of pain associated with i.v. propofol (p < 0.001). Injection of fentanyl itself caused pain in 28% of patients as compared to 2% in the lidocaine group. Mild local skin erythema was noted in 14% of patients with fentanyl venous retention versus 0% of patients with lidocaine venous retention. CONCLUSIONS Intravenous retention of fentanyl 150 micrograms, although less effective than that of lidocaine (p < 0.001), showed local analgesic effect in reducing the pain on propofol injection. The hypothetic mechanisms of action were speculated.
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Affiliation(s)
- W W Pang
- Department of Anesthesia, Show-Chwan Memorial Hospital, Changhua, Taiwan, R.O.C
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Abstract
The C-terminal domain of the human vitamin D receptor (hVDR) is essential for dimerization with retinoid X receptors and for transcriptional activation. To define the dimerization domain of the hVDR, a series of internal deletion mutants of the receptor were prepared beginning within the E domain and extending through the F domain to the C terminus. These mutant receptors were tested for dimerization and transcriptional activities by means of gel shift assay and beta-galactosidase assay, respectively, in a yeast system. The dimerization domain of the hVDR was localized to two separate but adjacent regions of the receptor molecule. In these experiments, the activation domain colocalized with dimerization. To more precisely delineate a relationship between these domains, region-specific random mutagenesis was carried out to detect mutants using error-prone PCR and a functional screen strategy employed using transformed yeast. Two classes of inactive receptors were identified: one in which both transcriptional activation and dimerization were compromised and a second in which only transcriptional activation was abolished. Most of the mutations responsible for these phenotypes were single. The studies suggest a separation between dimerization and transactivation domains. We reconstituted each of these hVDR mutants in a mammalian expression vector and evaluated them individually in COS-1 cells. All VDR mutants were transcriptionally active in this cellular background in response to 1,25-dihydroxyvitamin D3 although the potency of the hormone was reduced. The latter observation coincided with the observation that each mutant was compromised to some extent in binding affinity. These data clearly demonstrate the existence of an activation domain in hVDR that is separable from the domain involved in dimerization. Factors that couple hVDR to the general transcription apparatus in yeast through the activation domain in the hVDR, however, appear to be unrelated or dissimilar to those used in COS-1 cells.
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Affiliation(s)
- C H Jin
- Department of Skeletal Biology, Ligand Pharmaceuticals Inc., San Diego, California 92121, USA
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Abstract
By means of light- and electron-microscopic immunocytochemistry, we have demonstrated the expression of vacuolar H(+)-ATPase in mouse osteoclasts. In fully differentiated osteoclasts, intense immunolabeling was observed along the plasma membranes including those of ruffled borders and associated pale vesicles and vacuoles, whereas those of clear zones and basolateral cell surfaces were entirely free of immunoreaction. Specific expression of vacuolar H(+)-ATPase was also detected over polyribosomes and cisterns of the rough-surfaced endoplasmic reticulum. Multinucleated osteoclastic cells were suspended on dentine slices and cultured for 48 h in the presence or absence of either concanamycin B or bafilomycin A1, specific inhibitors of vacuolar H(+)-ATPase. Morphometric analysis of co-cultured dentine slices with backscattered electron microscopy revealed that both inhibitors strongly reduced the formation of resorption lacunae in a dose-dependent manner. These results suggest that vacuolar H(+)-ATPase is produced in the rough-surfaced endoplasmic reticulum, stored in the membrane vesicles, and transported into the ruffled border membranes of osteoclasts, and that this enzyme plays a key role in the creation of an acidic subosteoclastic microenvironment for the demineralization of co-cultured substrates.
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Affiliation(s)
- T Sasaki
- Department of Oral Anatomy, School of Dentistry, Showa University, Tokyo, Japan
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