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Lin CW, Hung CM, Chen WJ, Chen JC, Huang WY, Lu CS, Kuo ML, Chen SG. New Horizons of Macrophage Immunomodulation in the Healing of Diabetic Foot Ulcers. Pharmaceutics 2022; 14:pharmaceutics14102065. [PMID: 36297499 PMCID: PMC9606988 DOI: 10.3390/pharmaceutics14102065] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/16/2022] Open
Abstract
Diabetic foot ulcers (DFUs) are one of the most costly and troublesome complications of diabetes mellitus. The wound chronicity of DFUs remains the main challenge in the current and future treatment of this condition. Persistent inflammation results in chronic wounds characterized by dysregulation of immune cells, such as M1 macrophages, and impairs the polarization of M2 macrophages and the subsequent healing process of DFUs. The interactive regulation of M1 and M2 macrophages during DFU healing is critical and seems manageable. This review details how cytokines and signalling pathways are co-ordinately regulated to control the functions of M1 and M2 macrophages in normal wound repair. DFUs are defective in the M1-to-M2 transition, which halts the whole wound-healing machinery. Many pre-clinical and clinical innovative approaches, including the application of topical insulin, CCL chemokines, micro RNAs, stem cells, stem-cell-derived exosomes, skin substitutes, antioxidants, and the most recent Phase III-approved ON101 topical cream, have been shown to modulate the activity of M1 and M2 macrophages in DFUs. ON101, the newest clinically approved product in this setting, is designed specifically to down-regulate M1 macrophages and further modulate the wound microenvironment to favour M2 emergence and expansion. Finally, the recent evolution of macrophage modulation therapies and techniques will improve the effectiveness of the treatment of diverse DFUs.
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Affiliation(s)
| | | | | | | | | | | | - Ming-Liang Kuo
- Microbio Co., Ltd., Taipei 115, Taiwan
- Correspondence: (M.-L.K.); or (S.-G.C.); Tel.: +886-2-27031298 (ext. 550) (M.-L.K.); +886-2-27031098 (ext. 551) (S.-G.C.)
| | - Shyi-Gen Chen
- Oneness Biotech Co., Ltd., Taipei 106, Taiwan
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
- Correspondence: (M.-L.K.); or (S.-G.C.); Tel.: +886-2-27031298 (ext. 550) (M.-L.K.); +886-2-27031098 (ext. 551) (S.-G.C.)
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Lin CW, Chen CC, Huang WY, Chen YY, Chen ST, Chou HW, Hung CM, Chen WJ, Lu CS, Nian SX, Chen SG, Chang HW, Chang VH, Liu LY, Kuo ML, Chang SC. Restoring Pro-healing/remodeling- associated M2a/c Macrophages using ON101 Accelerates Diabetic Wound Healing. JID Innovations 2022; 2:100138. [PMID: 36017415 PMCID: PMC9396230 DOI: 10.1016/j.xjidi.2022.100138] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 01/05/2023] Open
Abstract
Diabetic wounds exhibit chronic inflammation and delayed tissue proliferation or remodeling, mainly owing to prolonged proinflammatory (M1) macrophage activity and defects in transition to prohealing/proremodeling (M2a/M2c; CD206+ and/or CD163+) macrophages. We found that topical treatment with ON101, a plant-based potential therapeutic for diabetic foot ulcers, increased M2c-like (CD163+ and CD206+) cells and suppressed M1-like cells, altering the inflammatory gene profile in a diabetic mouse model compared with that in the controls. An in vitro macrophage-polarizing model revealed that ON101 directly suppressed CD80+ and CD86+ M1-macrophage polarization and M1-associated proinflammatory cytokines at both protein and transcriptional levels. Notably, conditioned medium collected from ON101-treated M1 macrophages reversed the M1-conditioned medium‒mediated suppression of CD206+ macrophages. Furthermore, conditioned medium from ON101-treated adipocyte progenitor cells significantly promoted CD206+ and CD163+ macrophages but strongly inhibited M1-like cells. ON101 treatment also stimulated the expression of GCSF and CXCL3 genes in human adipocyte progenitor cells. Interestingly, treatment with recombinant GCSF protein enhanced both CD206+ and CD163+ M2 markers, whereas CXCL3 treatment only stimulated CD163+ M2 macrophages. Depletion of cutaneous M2 macrophages inhibited ON101-induced diabetic wound healing. Thus, ON101 directly suppressed M1 macrophages and facilitated the GCSF- and CXCL3-mediated transition from M1 to M2 macrophages, lowering inflammation and leading to faster diabetic wound healing.
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Affiliation(s)
| | - Chih-Chiang Chen
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan
- Department of Dermatology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | | | | | | | | | | | | | - Chia-Sing Lu
- NTU YongLin Institute of Health, National Taiwan University, Taipei, Taiwan
| | - Shi-Xin Nian
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Shyi-Gen Chen
- Oneness Biotech Co., Ltd., Taipei, Taiwan
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Hsuen-Wen Chang
- TMU Laboratory Animal Center, Office of Research and Development, Taipei Medical University, Taipei, Taiwan
| | - Vincent H.S. Chang
- TMU Laboratory Animal Center, Office of Research and Development, Taipei Medical University, Taipei, Taiwan
- Department of Physiology, School of Medicine, Taipei Medical University, Taipei, Taiwan
- The PhD Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Li-Ying Liu
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan
| | | | - Shun-Cheng Chang
- Division of Plastic Surgery, Integrated Burn & Wound Care Center, Department of Surgery, Shuang-Ho Hospital; Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Correspondence: Shun-Cheng Chang, Division of Plastic Surgery, Integrated Burn & Wound Care Center, Department of Surgery, Shuang-Ho Hospital; Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Number 291, Zhongzheng Road, Zhonghe District, New Taipei City 235, Taiwan.
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Lu CS, Lin CW, Chang YH, Chen HY, Chung WC, Lai WY, Ho CC, Wang TH, Chen CY, Yeh CL, Wu S, Wang SP, Yang PC. Antimetabolite pemetrexed primes a favorable tumor microenvironment for immune checkpoint blockade therapy. J Immunother Cancer 2021; 8:jitc-2020-001392. [PMID: 33243934 PMCID: PMC7692992 DOI: 10.1136/jitc-2020-001392] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2020] [Indexed: 12/26/2022] Open
Abstract
Background The immune checkpoint blockade (ICB) targeting programmed cell death-1 (PD-1) and its ligand (PD-L1) has been proved beneficial for numerous types of cancers, including non-small-cell lung cancer (NSCLC). However, a significant number of patients with NSCLC still fail to respond to ICB due to unfavorable tumor microenvironment. To improve the efficacy, the immune-chemotherapy combination with pemetrexed, cis/carboplatin and pembrolizumab (anti-PD-1) has been recently approved as first-line treatment in advanced NSCLCs. While chemotherapeutic agents exert beneficial effects, the underlying antitumor mechanism(s) remains unclear. Methods Pemetrexed, cisplatin and other chemotherapeutic agents were tested for the potential to induce PD-L1 expression in NSCLC cells by immunoblotting and flow cytometry. The ability to prime the tumor immune microenvironment was then determined by NSCLC/T cell coculture systems and syngeneic mouse models. Subpopulations of NSCLC cells responding differently to pemetrexed were selected and subjected to RNA-sequencing analysis. The key signaling pathways were identified and validated in vitro and in vivo. Results Pemetrexed induced the transcriptional activation of PD-L1 (encoded by CD274) by inactivating thymidylate synthase (TS) in NSCLC cells and, in turn, activating T-lymphocytes when combined with the anti-PD-1/PD-L1 therapy. Nuclear factor κB (NF-κB) signaling was activated by intracellular reactive oxygen species (ROSs) that were elevated by pemetrexed-mediated TS inactivation. The TS−ROS−NF-κB regulatory axis actively involves in pemetrexed-induced PD-L1 upregulation, whereas when pemetrexed fails to induce PD-L1 expression in NSCLC cells, NF-κB signaling is unregulated. In syngeneic mouse models, the combinatory treatment of pemetrexed with anti-PD-L1 antibody created a more favorable tumor microenvironment for the inhibition of tumor growth. Conclusions Our findings reveal novel mechanisms showing that pemetrexed upregulates PD-L1 expression and primes a favorable microenvironment for ICB, which provides a mechanistic basis for the combinatory chemoimmunotherapy in NSCLC treatment.
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Affiliation(s)
- Chia-Sing Lu
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Ching-Wen Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ya-Hsuan Chang
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Hsuan-Yu Chen
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Wei-Chia Chung
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Wei-Yun Lai
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chao-Chi Ho
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Tong-Hong Wang
- Tissue Bank, Chang Gung Memorial Hospital; Graduate Institute of Health Industry Technology and Research Center for Industry of Human Ecology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
| | - Chi-Yuan Chen
- Tissue Bank, Chang Gung Memorial Hospital; Graduate Institute of Health Industry Technology and Research Center for Industry of Human Ecology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
| | - Chen-Lin Yeh
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Sean Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Shu-Ping Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Pan-Chyr Yang
- Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan .,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.,Institute of Biomedical Sciences and Genomics Research Center, Academia Sinica, Taipei, Taiwan
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Lu CS, Shiau AL, Su BH, Hsu TS, Wang CT, Su YC, Tsai MS, Feng YH, Tseng YL, Yen YT, Wu CL, Shieh GS. Oct4 promotes M2 macrophage polarization through upregulation of macrophage colony-stimulating factor in lung cancer. J Hematol Oncol 2020; 13:62. [PMID: 32487125 PMCID: PMC7268452 DOI: 10.1186/s13045-020-00887-1] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 04/28/2020] [Indexed: 01/15/2023] Open
Abstract
Background Expression of Oct4 maintains cancer stem cell (CSC)-like properties in lung cancer cells and is correlated with poor prognosis of lung adenocarcinoma. M2-type tumor-associated macrophages (TAMs) promote cancer cell migration and metastasis. Tumor microenvironments promote monocyte differentiation into M2 TAMs via a complex cytokine-based connection. We explored the role of Oct4 in cytokine secretion in lung cancer and its impact on M2 TAM polarization. Methods Monocytes co-cultured with the conditioned medium from Oct4-overexpressing lung cancer cells were used to investigate M2 TAM differentiation. The inflammatory factors in the conditioned medium of Oct4-overexpressing A549 cells were examined using human inflammation antibody arrays. The correlations of Oct4, macrophage colony-stimulating factor (M-CSF), and M2 TAMs were validated in lung cancer cells, syngeneic mouse lung tumor models, and clinical samples of non-small cell lung cancer (NSCLC). Results Oct4-overexpressing A549 cells expressed elevated levels of M-CSF, which contributed to increased M2 macrophages and enhanced tumor migration. Overexpression of Oct4 enhanced tumor growth and reduced the survival of lung tumor-bearing mice, which was correlated with increased number of M2 macrophages in lung cancer. Notably, NSCLC patients with high expression levels of Oct4, M-CSF, and M2 TAMs had the poorest recurrence-free survival. A positive correlation between Oct4, M-CSF, and M2 TAMs was observed in the tumor tissue of NSCLC patient. Treatment with all-trans retinoic acid exerted anti-tumor effects and reduced M2 TAMs in tumor-bearing mice. Conclusions Our results indicate that Oct4 expressed by lung cancer cells promotes M2 macrophage polarization through upregulation of M-CSF secretion, leading to cancer growth and metastasis. Our findings also implicate that the Oct4/M-CSF axis in M2 macrophage polarization may be potential therapeutic targets for lung cancer.
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Affiliation(s)
- Chia-Sing Lu
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, 1, University Road, Tainan, Taiwan
| | - Ai-Li Shiau
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Bing-Hua Su
- School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Division of Thoracic Surgery, Department of Surgery, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tsui-Shan Hsu
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, 1, University Road, Tainan, Taiwan
| | - Chung-Teng Wang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Chu Su
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, 1, University Road, Tainan, Taiwan
| | - Ming-Shian Tsai
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yin-Hsun Feng
- Division of Hematology and Oncology, Department of Internal Medicine, Chi-Mei Medical Center, Tainan, Taiwan
| | - Yau-Lin Tseng
- Division of Thoracic Surgery, Department of Surgery, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Ting Yen
- Division of Thoracic Surgery, Department of Surgery, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chao-Liang Wu
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, 1, University Road, Tainan, Taiwan
| | - Gia-Shing Shieh
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, 1, University Road, Tainan, Taiwan. .,Department of Urology, Tainan Hospital, Ministry of Health and Welfare, Executive Yuan, Tainan, Taiwan.
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Lu CS, Shieh GS, Wang CT, Su BH, Su YC, Chen YC, Su WC, Wu P, Yang WH, Shiau AL, Wu CL. Chemotherapeutics-induced Oct4 expression contributes to drug resistance and tumor recurrence in bladder cancer. Oncotarget 2017; 8:30844-30858. [PMID: 27244887 PMCID: PMC5458172 DOI: 10.18632/oncotarget.9602] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Accepted: 04/23/2016] [Indexed: 12/18/2022] Open
Abstract
Cancer cells initially characterized as sensitive to chemotherapy may acquire resistance to chemotherapy and lead to tumor recurrence through the expansion of drug-resistant population. Acquisition of drug resistance to conventional chemotherapy is a major obstacle in the treatment of recurrent cancer. Here we investigated whether anticancer drugs induced Oct4 expression, thereby contributing to acquired drug resistance and tumor recurrence in bladder cancer. We identified a positive correlation of Oct4 expression with tumor recurrence in 122 clinical specimens of superficial high-grade (stages T1-2) bladder transitional cell carcinoma (TCC). Increased Oct4 levels in bladder tumors were associated with short recurrence-free intervals in the patients. Chemotherapy induced Oct4 expression in bladder cancer cells. Notably, treatment with cisplatin increased CD44-positive bladder cancer cells expressing Oct4, representing cancer stem-like cell subpopulation. Forced expression of Oct4 reduced, whereas knockdown of Oct4 enhanced, drug sensitivity in bladder cancer cells. Furthermore, tumor cells overexpressing Oct4 responded poorly to cisplatin in vivo. In regard to clinical relevance, inhibition of Oct4 by all-trans retinoic acid (ATRA) synergistically increased sensitivity to cisplatin in bladder cancer cells. Furthermore, the combination of cisplatin and ATRA was superior to cisplatin alone in suppressing tumor growth. Therefore, our results provide evidence that Oct4 increases drug resistance and implicate that inhibition of Oct4 may be a therapeutic strategy to circumvent drug resistance.
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Affiliation(s)
- Chia-Sing Lu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Gia-Shing Shieh
- Department of Urology, Tainan Hospital, Ministry of Health and Welfare, Executive Yuan, Tainan, Taiwan
| | - Chung-Teng Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Bing-Hua Su
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Chu Su
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Cheng Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wu-Chou Su
- Department of Internal Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Pensee Wu
- Institute for Science & Technology in Medicine, Keele University, Keele, United Kingdom
| | - Wen-Horng Yang
- Department of Urology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Ai-Li Shiau
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chao-Liang Wu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Liou CW, Chuang JH, Chen JB, Tiao MM, Wang PW, Huang ST, Huang TL, Lee WC, Weng SW, Huang PH, Chen SD, Chen RS, Lu CS, Lin TK. Mitochondrial DNA variants as genetic risk factors for Parkinson disease. Eur J Neurol 2016; 23:1289-300. [PMID: 27160373 DOI: 10.1111/ene.13020] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 03/22/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND PURPOSE Investigation of the relationship between mitochondrial DNA (mtDNA) variants and Parkinson disease (PD) remains an issue awaiting more supportive evidence. Moreover, an affirming cellular model study is also lacking. METHODS The index mtDNA variants and their defining mitochondrial haplogroup were determined in 725 PD patients and 744 non-PD controls. Full-length mtDNA sequences were also conducted in 110 cases harboring various haplogroups. Cybrid cellular models, composed by fusion of mitochondria-depleted rho-zero cells and donor mitochondria, were used for a rotenone-induced PD simulation study. RESULTS Multivariate logistic regression analysis revealed that subjects harboring the mitochondrial haplogroup B5 have resistance against PD (odds ratio 0.50, 95% confidence interval 0.32-0.78; P = 0.002). Furthermore, a composite mtDNA variant group consisting of A10398G and G8584A at the coding region was found to have resistance against PD (odds ratio 0.50, 95% confidence interval 0.33-0.78; P = 0.001). In cellular studies, B4 and B5 cybrids were selected according to their higher resistance to rotenone, in comparison with cybrids harboring other haplogroups. The B5 cybrid, containing G8584A/A10398G variants, showed more resistance to rotenone than the B4 cybrid not harboring these variants. This is supported by findings of low reactive oxygen species generation and a low apoptosis rate in the B5 cybrid, whereas a higher expression of autophagy was observed in the B4 cybrid particularly under medium dosage and longer treatment time with rotenone. CONCLUSIONS Our studies, offering positive results from clinical investigations and cybrid experiments, provide data supporting the role of variant mtDNA in the risk of PD.
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Affiliation(s)
- C W Liou
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan. .,Mitochondrial Research Unit, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
| | - J H Chuang
- Department of Pediatrics Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - J B Chen
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - M M Tiao
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - P W Wang
- Division of Metabolism, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - S T Huang
- Department of Chinese Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - T L Huang
- Department of Psychiatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - W C Lee
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - S W Weng
- Division of Metabolism, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - P H Huang
- Mitochondrial Research Unit, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - S D Chen
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - R S Chen
- Section of Movement Disorder, Department of Neurology, Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou Medical Center, Taoyuan, Taiwan
| | - C S Lu
- Section of Movement Disorder, Department of Neurology, Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou Medical Center, Taoyuan, Taiwan
| | - T K Lin
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Mitochondrial Research Unit, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
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Lu CS, Shiau AL, Shieh GS, Su BH, Su WC, Yang WH, Wu CL. Abstract 4701: Acquisition of Oct-4 upregulation transactivates MDR1 and is associated with increased tumor recurrence in bladder cancer. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-4701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Platinum-based drug like cisplatin is the standard first-line drug to treat patients with bladder cancer. However, tumors may recur and develop into multiple-drug resistant characteristics. The acquisition of resistance to conventional chemotherapy is a challenge in the treatment of bladder cancer relapse. Cancer stem cell (CSC) hypothesis has been an attractive theory. CSCs can resist therapeutic assaults, giving rise to multiple drug resistance and promotion of tumor relapse and metastasis. It has been shown that the fraction of cancer cells expressing MDR1 that functions as an energy-dependent drug efflux pump may be associated with Oct-4 expression. We have demonstrated that Oct-4 expression in bladder cancer predicts tumor progression. In the present study, we proposed that Oct-4 expression in bladder cancer increases MDR1 gene expression and thereby results in multiple drug resistance. We found a positive correlation between Oct-4 and MDR1 expression levels in clinical samples of bladder cancer. Furthermore, overexpression of Oct-4 increased MDR1 expression, which resulted in poor response to cisplatin in human bladder transitional cell carcinoma cells. Conversely, knockdown of Oct-4 reduced MDR1 expression and rendered cells hypersensitive to cisplatin. We also verified that Oct-4 transactivated the MDR1 gene promoter by binding to the Oct-4 response element (ORE). More importantly, Oct-4 and MDR1 gene expression could be induced by treatment with cisplatin, suggesting that Oct-4 is a member of the MDR1 enhanceosome. Our data can explain, in part, the high recurrence rate and drug resistance of bladder cancer. For clinical implication, we demonstrated that reduction of Oct-4 expression by all-trans retinoic acid, a derivative of vitamin A, improved sensitivity of bladder cancer cells to gemcitabine and cisplatin. In addition, we found that high expression levels of Oct-4 and MDR1 were associated with high tumor recurrence. Taken together, our results provide evidence that Oct-4 plays an important role in cisplatin-acquired resistance in bladder cancer. They also implicate Oct-4 as a therapeutic target.
Note: This abstract was not presented at the meeting.
Citation Format: Chia-Sing Lu, Ai-Li Shiau, Gia-Shing Shieh, Bing-Hua Su, Wu-Chou Su, Wen-Horng Yang, Chao-Liang Wu. Acquisition of Oct-4 upregulation transactivates MDR1 and is associated with increased tumor recurrence in bladder cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4701. doi:10.1158/1538-7445.AM2014-4701
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Affiliation(s)
- Chia-Sing Lu
- 1Department of Biochemistry and Molecular Biology, Tainan City, Taiwan
| | - Ai-Li Shiau
- 2Department of Microbiology and Immunology, National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Gia-Shing Shieh
- 3Department of Urology, Tainan Hospital, Department of Health, Executive Yuan, Taiwan, Tainan City, Taiwan
| | - Bing-Hua Su
- 4Department of Biochemistry and Molecular Biology, National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Wu-Chou Su
- 5Department of Internal Medicine,National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Wen-Horng Yang
- 6Department of Urology, National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Chao-Liang Wu
- 4Department of Biochemistry and Molecular Biology, National Cheng Kung University Medical College, Tainan City, Taiwan
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Shen PC, Lu CS, Shiau AL, Lee CH, Jou IM, Hsieh JL. Lentiviral small hairpin RNA knockdown of macrophage inflammatory protein-1γ ameliorates experimentally induced osteoarthritis in mice. Hum Gene Ther 2013; 24:871-82. [PMID: 24016310 PMCID: PMC3787402 DOI: 10.1089/hum.2012.189] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 09/06/2013] [Indexed: 01/16/2023] Open
Abstract
Immune cells are involved in the pathogenesis of osteoarthritis (OA). CD4(+) T cells were activated during the onset of OA and induced macrophage inflammatory protein (MIP)-1γ expression and subsequent osteoclast formation. We evaluated the effects of local knockdown of MIP-1γ in a mouse OA model induced by anterior cruciate ligament transection. The mouse macrophage cell lines and osteoclast-like cells generated from immature hematopoietic monocyte/macrophage progenitors of murine bone marrow were cocultured with either receptor activator of NFκB ligand (RANKL) or CD4(+) T cells. The levels of MIP-1γ and RANKL in cells and mice were examined by enzyme-linked immunosorbent assay (ELISA). The osteoclastogenesis was evaluated using tartrate-resistant acid phosphatase and cathepsin K staining. OA was induced in one hind-leg knee joint of B6 mice. Lentiviral vector encoding MIP-1γ small hairpin RNA (shRNA) and control vector were individually injected intra-articularly into the knee joints, which were histologically assessed for manifestations of OA. The expression of MIP-1γ and matrix metalloproteinase (MMP)-13 and the infiltration of CD4(+) T cells, macrophages, and osteoclastogenesis in tissues were examined using immunohistochemistry. CD4(+) T cells were involved in OA by inducing MIP-1γ expression in osteoclast progenitors and the subsequent osteoclast formation. Neutralizing MIP-1γ with a specific antibody abolishes RANKL-stimulated and CD4(+) T-cell-stimulated osteoclast formation. MIP-1γ levels were significantly higher in synovium and the chondro-osseous junction of joints 90 days postsurgery. The number of infiltrated CD4(+) T cells and macrophages and IL-1β expression were reduced in the synovial tissues of mice treated with MIP-1γ shRNA. Histopathological examinations revealed that mice treated with MIP-1γ shRNA had less severe OA than control mice had, as well as decreased osteoclast formation and MMP-13 expression. Locally inhibiting MIP-1γ expression may ameliorate disease progression and provide a new OA therapy.
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Affiliation(s)
- Po-Chuan Shen
- Department of Orthopedic Surgery, Tainan Hospital, Department of Health, Executive Yuan, Tainan 70043, Taiwan
| | - Chia-Sing Lu
- Department of Biochemistry and Molecular Biology, National Cheng Kung University, Tainan 70101, Taiwan
| | - Ai-Li Shiau
- Department of Microbiology and Immunology, National Cheng Kung University, Tainan 70101, Taiwan
| | - Che-Hsin Lee
- Department of Microbiology, School of Medicine, China Medical University, Taichung 40402, Taiwan
| | - I-Ming Jou
- Department of Orthopedics, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
| | - Jeng-Long Hsieh
- Department of Nursing, Chung Hwa University of Medical Technology, Tainan 71703, Taiwan
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9
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Hsieh JL, Lu CS, Huang CL, Shieh GS, Su BH, Su YC, Lee CH, Chang MY, Wu CL, Shiau AL. Acquisition of an enhanced aggressive phenotype in human lung cancer cells selected by suboptimal doses of cisplatin following cell deattachment and reattachment. Cancer Lett 2012; 321:36-44. [DOI: 10.1016/j.canlet.2012.03.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Revised: 03/11/2012] [Accepted: 03/17/2012] [Indexed: 12/28/2022]
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10
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Chen KT, Lu CS, Chang TH, Lai YY, Chang TH, Wu CW, Chen CC. Comparison of photodegradative efficiencies and mechanisms of Victoria Blue R assisted by Nafion-coated and fluorinated TiO2 photocatalysts. J Hazard Mater 2010; 174:598-609. [PMID: 19815344 DOI: 10.1016/j.jhazmat.2009.09.094] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Revised: 08/26/2009] [Accepted: 09/17/2009] [Indexed: 05/28/2023]
Abstract
The purposes of this research were to study the effects of two modified photocatalysts, Nafion-coated TiO(2) and fluorinated TiO(2), and photocatalytic degradation of Victoria Blue R in aqueous solution. Photocatalytic degradation of Victoria Blue R was accelerated by the modified photocatalysts. Bulk and surface characterizations of the resulting powders were carried out. Attachment of the anions to the TiO(2) surface using the Nafion-coated-TiO(2) possibly results in increased adsorption of the cationic dye, and the degradation rate is larger for the cationic dye. It was found that Victoria Blue R on the two illuminated TiO(2) surfaces underwent very different changes. To obtain a better understanding on the mechanistic details of this modified-TiO(2)-assisted photodegradation of the Victoria Blue R dye with UV irradiation, a large number of intermediates of the process were separated, identified, and characterized by a high-performance liquid chromatography-mass spectrometry technique. Several probable photodegradation pathways were proposed and discussed.
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Affiliation(s)
- K T Chen
- Department of General Education, Ming Hsing University of Science and Technology, 304 Taiwan, ROC
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11
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Tan EK, Peng R, Wu YR, Wu RM, Wu-Chou YH, Tan LC, An XK, Chen CM, Fook-Chong S, Lu CS. LRRK2 G2385R modulates age at onset in Parkinson's disease: A multi-center pooled analysis. Am J Med Genet B Neuropsychiatr Genet 2009; 150B:1022-3. [PMID: 19152345 DOI: 10.1002/ajmg.b.30923] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Tan EK, Lu CS, Peng R, Teo YY, Wu-Chou YH, Chen RS, Weng YH, Chen CM, Fung HC, Tan LC, Zhang ZJ, An XK, Lee-Chen GJ, Lee MC, Fook-Chong S, Burgunder JM, Wu RM, Wu YR. Analysis of the UCHL1 genetic variant in Parkinson's disease among Chinese. Neurobiol Aging 2009; 31:2194-6. [PMID: 19329225 DOI: 10.1016/j.neurobiolaging.2008.11.008] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 11/29/2008] [Indexed: 10/21/2022]
Abstract
The inverse association of the functional ubiquitin carboxy-terminal hydrolase L1 (UCHL1) S18Y variant with Parkinson's disease (PD) among Caucasian populations has been debated. We conducted a large-scale analysis to investigate the age-of-onset effect of the UCHL1 variant in PD among ethnic Chinese. Individual data sets from 5 centers comprising a total of 4088 study subjects were analyzed. In the univariate analysis, only data from 1 center showed a trend towards a protective effect among young subjects. However, in the combined analysis, no significant association between the UCHL1 variant and PD was detected (A allele frequency 0.531 vs. 0.528, p=0.87, OR 1.01, 95% CI 0.92-1.1). Among subjects less than 60 years old, the OR is 0.99 (95% CI 0.84-1.16, p=0.88). A multivariate logistic regression analysis showed that family history, UCHL1 variant and the interaction of UCHL1 variant and age at onset (p=0.816) were not significantly associated with PD.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, National Neuroscience Institute, Singapore.
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13
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Chen CC, Lu CS, Chung YC, Jan JL. UV light induced photodegradation of malachite green on TiO2 nanoparticles. J Hazard Mater 2007; 141:520-8. [PMID: 16934397 DOI: 10.1016/j.jhazmat.2006.07.011] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 06/29/2006] [Accepted: 07/10/2006] [Indexed: 05/11/2023]
Abstract
The photodegradation of malachite green (MG), a cationic triphenylmethane dye, is examined both under different pH values and amounts of TiO(2). After 15W UV-365nm irradiation for 4h, ca. 99.9% of MG was degraded with addition of 0.5gL(-1) TiO(2) to solutions containing 50mgL(-1) of the MG dye. The HPLC-PDA-ESI-MS technique was used to obtain a better understanding on the mechanistic details of this TiO(2)-assisted photodegradation of the MG dye with UV irradiation. Five intermediates of the process were separated, identified, and characterized for the first time. The results indicated that the N-de-methylation degradation of MG dye took place in a stepwise manner to yield mono-, di-, tri-, and tetra-N-de-methylated MG species generated during the processes. Under acidic conditions, the results indicated that the photodegradation mechanism is favorable to cleavage of the whole conjugated chromophore structure of the MG dye. Under basic conditions, the results showed that the photodegradation mechanism is favorable to a formation of a series of N-de-methylated intermediates of the MG dye.
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Affiliation(s)
- C C Chen
- Department of General Education, National Taichung Nursing College, Taichung 403, Taiwan.
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14
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Tan EK, Zhao Y, Skipper L, Tan MG, Di Fonzo A, Sun L, Fook-Chong S, Tang S, Chua E, Yuen Y, Tan L, Pavanni R, Wong MC, Kolatkar P, Lu CS, Bonifati V, Liu JJ. The LRRK2 Gly2385Arg variant is associated with Parkinson’s disease: genetic and functional evidence. Hum Genet 2006; 120:857-63. [PMID: 17019612 DOI: 10.1007/s00439-006-0268-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Accepted: 09/11/2006] [Indexed: 10/24/2022]
Abstract
Evidence of LRRK2 haplotypes associated with Parkinson's disease (PD) risk was recently found in the Chinese population from Singapore, and a common LRRK2 missense variant, Gly2385Arg, was independently detected as a putative risk factor for PD in the Chinese population from Taiwan. To test the association between the Gly2385Arg variant in a large case-control sample of Chinese ethnicity from Singapore, and to perform functional studies of the wild type and Gly2385Arg LRRK2 protein in human cell lines. In a case-control study involving 989 Chinese subjects, the frequency of the heterozygous Gly2385Arg genotype was higher in PD compared to controls (7.3 vs. 3.6%, odds ratio = 2.1, 95% CI: 1.1-3.9, P = 0.014); these values yield an estimated population attributable risk (PAR) of approximately 4%. In a multivariate logistic regression analysis with the disease group (PD vs. controls) as the dependent variable and the genotype as an independent factor with adjustments made for the effect of age and gender, the heterozygous Gly2385Arg genotype remained associated with an increased risk of PD compared to wild type genotype (odds ratio = 2.67, 95% CI: 1.43-4.99, P = 0.002). The glycine at position 2385 is a candidate site for N-myristoylation, and the Gly2385Arg variant replaces the hydrophobic glycine with the hydrophilic arginine, and increases the net positive charge of the LRRK2 WD40 domain. In transfection studies, we demonstrated that both the wild type and Gly2385Arg variant LRRK2 protein localize to the cytoplasm and form aggregates. However, under condition of oxidative stress, the Gly2385Arg variant was more toxic and associated with a higher rate of apoptosis. Our study lends support to the contention that the Gly2385Arg is a common risk factor for PD in the Chinese population. Our bioinformatics and in-vitro studies also suggest that the Gly2385Arg variant is biologically relevant and it might act through pro-apoptotic mechanisms.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore, Singapore
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15
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Hatano Y, Sato K, Elibol B, Yoshino H, Yamamura Y, Bonifati V, Shinotoh H, Asahina M, Kobayashi S, Ng AR, Rosales RL, Hassin-Baer S, Shinar Y, Lu CS, Chang HC, Wu-Chou YH, Ataç FB, Kobayashi T, Toda T, Mizuno Y, Hattori N. PARK6-linked autosomal recessive early-onset parkinsonism in Asian populations. Neurology 2006; 63:1482-5. [PMID: 15505170 DOI: 10.1212/01.wnl.0000142258.29304.fe] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors performed linkage analysis in 39 families with autosomal recessive early-onset PD (AR-EOPD) negative for parkin and DJ-1 mutations. Eight families including three Japanese, two Taiwanese, one Turkish, one Israeli, and one Philippine showed evidence of linkage with PARK6 with multipoint log of the odds (lod) score of 9.88 at D1S2732. The results indicate worldwide distribution of PARK6-linked parkinsonism.
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Affiliation(s)
- Y Hatano
- Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan
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16
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Abstract
We here summarize the results of genetic investigations on a series of 82 parkinsonian patients from 60 families in Taiwan. We found 13 parkin patients in 7 families (12%), 2 PINK1 sibs from 1 family, and 1 LRRK2 patient from 1 family with I2012T mutation. We also identified SCA2 in 8 patients from 5 families (8%) and SCA3 in 3 patients from 1 family, all presenting with parkinsonian phenotype. In the available patients with parkin, PINK1, SCA2 and SCA3, the dopamine transporter (DAT) scan revealed that the reduction of uptake was primarily observed in the bilateral putamen, basically sharing a similar pattern with that in idiopathic Parkinson's disease. We concluded that the genetic causes contributed to about 25% of our series of familial parkinsonism. The parkin mutations and SCA2 were the most frequent genetic causes in our series with Chinese ethnicity. The results of DAT scan indicated that bilateral putamen was essentially involved in various genetically-caused familial parkinsonism.
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Affiliation(s)
- C S Lu
- Movement Disorders Section, Department of Neurology and Neuroscience Research Center, Human Molecular Genetic Laboratory, Chang Gung Memorial Hospital and Chang Gung University, Taiwan.
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17
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Tsai CH, Chang FC, Su YC, Tsai FJ, Lu MK, Lee CC, Kuo CC, Yang YW, Lu CS. Two novel mutations of the glycine receptor gene in a Taiwanese hyperekplexia family. Neurology 2004; 63:893-6. [PMID: 15365143 DOI: 10.1212/01.wnl.0000138566.65519.67] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors report a Taiwanese family with autosomal recessive hyperekplexia. Two novel mutations, W96C (from the paternal allele) and R344X (from the maternal allele), which are located in exon 4 and exon 7 of the GLRA1 gene, were identified in this family. A series of electrophysiologic investigations were conducted in one of the probands, and the results suggest that the "startle center" is located subcortically.
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MESH Headings
- Acoustic Stimulation
- Adult
- Amino Acid Substitution
- Brain/physiopathology
- DNA Mutational Analysis
- Electromyography
- Evoked Potentials, Motor
- Female
- Genes, Recessive
- Humans
- Magnetics
- Mutation, Missense
- Pedigree
- Physical Stimulation
- Point Mutation
- Polymorphism, Single-Stranded Conformational
- Receptors, Glycine/genetics
- Reflex, Abnormal/genetics
- Reflex, Startle/genetics
- Reflex, Startle/physiology
- Reflex, Stretch/genetics
- Sequence Analysis, DNA
- Taiwan/epidemiology
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Affiliation(s)
- C H Tsai
- Neuroscience Laboratory, Department of Neurology, China Medical University Hospital, Taichung, Taiwan
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18
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Tsai PC, Chang FC, Tsai CH, Jang FR, Shen AN, Huang YT, Lai SC, Yeh TH, Lu MK, Lu CS. Focal hand myoclonus caused by a small hematoma underneath the cerebral motor cortex. Eur Neurol 2003; 50:114-7. [PMID: 12944720 DOI: 10.1159/000072512] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- P C Tsai
- Department of Neurology, Chang Gung Memorial Hospital, Taipei, Taiwan
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19
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Tsai CH, Lo SK, See LC, Chen HZ, Chen RS, Weng YH, Chang FC, Lu CS. Environmental risk factors of young onset Parkinson's disease: a case-control study. Clin Neurol Neurosurg 2002; 104:328-33. [PMID: 12140099 DOI: 10.1016/s0303-8467(02)00027-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [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: 11/21/2022]
Abstract
While the cause of Parkinson's disease (PD) remains unknown, recent evidence suggests certain environmental factors, such as well water drinking, herbicides and pesticides exposure, and neurotoxins, may trigger the chain of oxidative reactions culminating in the death of dopaminergic neurons in substantia nigra to cause parkinsonism. Most studies to date focused on PD with old age onset. However, there is a peculiar group of parkinsonian patients, the young onset Parkinson's disease (YOPD), in whom the age of onset is before 40. It is intriguing to know whether earlier exposure to the putative neurotoxin(s) may contribute to the earlier onset. We therefore conducted this case-control study in which 60 PD patients, 30 YOPD patients and the same number of age- and sex-matched young controls were included. Using logistic regression, we found well water drinking and head injury were risk factors for the development of YOPD. When YOPD patients were compared with PD, we found head injury and exercise were the significant predictors. Keeping all other variables constant, head injury was a risk factor and exercise appeared to be a protective factor. We conclude early exposure to well water drinking and head trauma may trigger and expedite the appearance of parkinsonian features, but such acceleration may be prevented through regular exercise.
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Affiliation(s)
- C H Tsai
- Neuroscience Laboratory, Department of Neurology, China Medical College Hospital, 2, Yuh-Der road, 404, Taichung, Taiwan, ROC.
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20
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Silverman DH, Small GW, Chang CY, Lu CS, Kung De Aburto MA, Chen W, Czernin J, Rapoport SI, Pietrini P, Alexander GE, Schapiro MB, Jagust WJ, Hoffman JM, Welsh-Bohmer KA, Alavi A, Clark CM, Salmon E, de Leon MJ, Mielke R, Cummings JL, Kowell AP, Gambhir SS, Hoh CK, Phelps ME. Positron emission tomography in evaluation of dementia: Regional brain metabolism and long-term outcome. JAMA 2001; 286:2120-7. [PMID: 11694153 DOI: 10.1001/jama.286.17.2120] [Citation(s) in RCA: 555] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Deficits in cerebral glucose utilization have been identified in patients with cognitive dysfunction attributed to various disease processes, but their prognostic and diagnostic value remains to be defined. OBJECTIVE To assess the sensitivity and specificity with which cerebral metabolic patterns at a single point in time forecast subsequent documentation of progressive dementia. DESIGN, SETTING, AND PATIENTS Positron emission tomography (PET) studies of [(18)F]fluorodeoxyglucose in 146 patients undergoing evaluation for dementia with at least 2 years' follow-up for disease progression at the University of California, Los Angeles, from 1991 to 2000, and PET studies in 138 patients undergoing evaluation for dementia at an international consortium of facilities, with histopathological diagnoses an average of 2.9 years later, conducted from 1984 to 2000. MAIN OUTCOME MEASURES Regional distribution of [(18)F]fluorodeoxyglucose in each patient, classified by criteria established a priori as positive or negative for presence of a progressive neurodegenerative disease in general and of Alzheimer disease (AD) specifically, compared with results of longitudinal or neuropathologic analyses. RESULTS Progressive dementia was detected by PET with a sensitivity of 93% (191/206) and a specificity of 76% (59/78). Among patients with neuropathologically based diagnoses, PET identified patients with AD and patients with any neurodegenerative disease with a sensitivity of 94% and specificities of 73% and 78%, respectively. The negative likelihood ratio of experiencing a progressive vs nonprogressive course over the several years following a single negative brain PET scan was 0.10 (95% confidence interval, 0.06-0.16), and the initial pattern of cerebral metabolism was significantly associated with the subsequent course of progression overall (P<.001). CONCLUSION In patients presenting with cognitive symptoms of dementia, regional brain metabolism was a sensitive indicator of AD and of neurodegenerative disease in general. A negative PET scan indicated that pathologic progression of cognitive impairment during the mean 3-year follow-up was unlikely to occur.
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Affiliation(s)
- D H Silverman
- Ahmanson Biological Imaging Center, CHS AR-144, Department of Molecular and Medical Pharmacology, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095-6942, USA.
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21
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Abstract
Ambient air particle concentrations were sampled by two total suspended particle (TSP) samplers, PM10/PM2.5 specific sampler and micro-orifice uniform deposit impactor (MOUDI) during July-October 2000 at a traffic sampling site in central Taiwan. The average TSP concentration (194 microg/m3) was about a factor of two higher than that of the fraction <2.5 microm (93.2 microg/m3). The mean level of the fraction <10 microm collected by MOUDI (93.2 microg/m3) was about 1 1/2 times higher than that of the size class <2.5 microm (43.8 microg/m3). Furthermore, this fraction showed a certain correlation with the TSP concentration. The particle size distribution was bimodal in the ambient air at the traffic site. The major peaks appear at particle diameters between 0.56-1.0 and 3.2-5.6 microm. The percentages of anions contained in TSP were 0.24% F-, 13.7% Cl, 0.52% Br, 12.0% NO-, 18.9% NO2-, and 54.6% SO2-. The Cl-, NO2-, and NO3- size distributions were all unimodal and the major peaks appeared at 3.2-5.6 microm. The SO2 size distribution was bimodal, with major peaks at 0.32-0.56 and 3.2-5.6.
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Affiliation(s)
- K F Chang
- Department of Environmental Engineering, National Chung Hsing University, Taichung, Taiwan, ROC
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22
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Lu CS, Weng YH, Wu T, Tsai CH, Chen RS, Lee JD, Lee ST. Posteroventral pallidotomy for advanced Parkinson's disease. Chang Gung Med J 2001; 24:409-17. [PMID: 11565246] [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: 02/21/2023]
Abstract
BACKGROUND Provoked by the limitations and late complications of levodopa therapy, the advances in stereotactic surgery, and better understanding of the pathophysiology of the basal ganglia, the role of pallidotomy in the treatment of advanced Parkinson's disease (PD) has been revived. METHODS We included 11 patients with advanced PD, who had a good response to levodopa but had late complications of motor fluctuation and severe dyskinesia. The internal globus pallidus was identified with computed tomography prior to posteroventral pallidotomy and it was reaffirmed by microelectrode recording during surgery. Clinical evaluations were carried out in both the "on" and "off" motor periods at baseline and at 1 week, 3 months, 6 months and 1 year postoperatively. Repeated measures ANOVA followed by multiple comparisons were used for statistical analysis. RESULTS Dyskinesia improved bilaterally but only significantly in the contralateral limbs. This benefit was sustained up to 1 year. Parkinsonism, particularly contralateral tremor and rigidity, improved in the "off" motor period but not in the "on" motor period. The average Unified Parkinson's Disease Rating Scale motor score was reduced 36% at 3 months and 26% at 1 year in the "off" motor period. Both of the mean Hoehn and Yahr staging and Schwab and England activities of daily living score improved in "off" motor period. Improvement in parkinsonism, however, did not reach a significant level. Mild dysarthria and unstable gait were observed temporarily in 2 patients. Mild weakness in the contralateral limbs was found in 1 patient. CONCLUSIONS Unilateral pallidotomy guided by microelectrode recording is helpful for severe levodopa-induced dyskinesia in advanced PD. Contralateral parkinsonian disabilities also improve in the "off" motor period.
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Affiliation(s)
- C S Lu
- Movement Disorders Unite, First Department of Neurology, Chang Gung Memorial Hospital, Taipei
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23
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Lu CS, Ren XM, Hu CJ, Zhu HZ, Meng QJ. The inclusion compound of a new ionizable derivative of beta-cyclodextrin with ferrocenium drug. Chem Pharm Bull (Tokyo) 2001; 49:818-21. [PMID: 11456085 DOI: 10.1248/cpb.49.818] [Citation(s) in RCA: 12] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A new beta-cyclodextrin (beta-CD) derivative, mono[6-deoxy-6-(2-butenedinitrile-2,3-dimercapto sodium salt)]-beta-CD (6-mnt-beta-CD), and its inclusion compound with a ferrocenium drug, have been prepared and characterized by IR, UV, 13C-NMR spectroscopy, and mass spectrometry, elemental analysis, thermogravimetry, and cyclic voltammetry (CV). The interplay between the side-arm anion of beta-CD and the ferrocenium (guest) in the inclusion compound 6-mnt-beta-CD-/Fc+ has been investigated by 13C-NMR, UV, IR, and thermogravimetric methods. Charge transfer from the anion to the cation in 6-mnt-beta-CD-/Fc+ was then experimentally identified. The interaction between the guest and the host with side-arm in 6-mnt-beta-CD-/Fc+ resulted in smaller positive potential shifts compared to that in the inclusion compound [beta-CD/Fc+]BF4-.
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Affiliation(s)
- C S Lu
- Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing University, PR China
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24
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Jaing TH, Chiu CH, Lo WC, Lu CS, Chang KW. Epstein-Barr virus-associated hemophagocytic syndrome masquerading as lymphoma: a case report. J Microbiol Immunol Infect 2001; 34:147-9. [PMID: 11456362] [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: 02/20/2023]
Abstract
Virus-associated hemophagocytic syndrome (VAHS) is a non-neoplastic, generalized histiocytic proliferation with prominent hemophagocytosis associated with a systemic viral infection. Although Epstein-Barr virus (EBV) is one candidate virus for this association, thorough serologic and molecular biologic studies to determine the presence of the viral infection have been lacking in many reports. Whereas elevated liver function tests are common findings in patients with VAHS, exudative ascites and abdominal lymphadenopathy are rare. We describe a case of EBV-AHS masquerading as lymphoma in which treatment with intravenous immunoglobulins was associated with complete clinical remission at 2 years and 6 months after the onset. Regardless of the exact mechanism responsible for ascites formation in VAHS, this case adds support to the possible involvement of EBV in patients with abdominal lymphadenopathy and ascites.
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Affiliation(s)
- T H Jaing
- Department of Medicine, Chang Gung Children's Hospital, Taoyuan, Taiwan, ROC
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25
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Tzen KY, Lu CS, Yen TC, Wey SP, Ting G. Differential diagnosis of Parkinson's disease and vascular parkinsonism by (99m)Tc-TRODAT-1. J Nucl Med 2001; 42:408-13. [PMID: 11337515] [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: 02/20/2023] Open
Abstract
UNLABELLED The aim of this study was to use brain SPECT to differentiate vascular parkinsonism (VP) from Parkinson's disease. METHODS Fourteen VP patients (age range, 59-87 y; mean age, 70 +/- 7.5 y), 30 Parkinson's disease patients (age range, 54-84 y; mean age, 65 +/- 8.8 y), and 26 healthy (control) individuals (age range, 50-85 y; mean age, 60 +/- 9 y) were examined. A 925-MBq (25 mCi) dose of (99m)Tc-TRODAT-1 was injected intravenously, and brain SPECT images were acquired 4 h after injection. The ratio of specific to nonspecific striatal (99m)Tc-TRODAT-1 binding was measured and compared. RESULTS After a region-of-interest analysis of the images from VP patients, Parkinson's disease patients, and healthy volunteers was performed to obtain ratios of putamen to occipital and striatal to occipital binding as a measurement of specific binding to the dopamine transporters in these regions of the brain, where dopamine neurons are concentrated, the specific binding in the 14 VP patients was slightly lower than but not statistically different from that of the healthy individuals in both putamen and caudate areas. A significant decrease in uptake of (99m)Tc-TRODAT-1 in the striatum (P<0.01) was found in Parkinson's disease patients. Reduction of the uptake was more pronounced in the contralateral putamen of Parkinson's disease patients than that of VP patients (P<0.001). A significant bilateral striatal asymmetry was also observed in Parkinson's disease patients but not in VP patients (P< 0.01). CONCLUSION Our findings clearly show that, for VP patients, (99m)Tc-TRODAT-1 SPECT is a reliable method to differentiate VP from Parkinson's disease. Further studies, including those to differentiate Parkinson's disease from arteriosclerotic parkinsonism and patients with both VP and Parkinson's disease, are needed to help rule out the possibility of Parkinson's disease as early as possible.
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Affiliation(s)
- K Y Tzen
- Departments of Nuclear Medicine and Neurology, Chang Gung Memorial Hospital at Lin-Ko and Keelung, Taipei Medical Center and School of Medicine, Chang Gung University, Taiwan
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Kao PF, Tzen KY, Yen TC, Lu CS, Weng YH, Wey SP, Ting G. The optimal imaging time for [99Tcm]TRODAT-1/SPET in normal subjects and patients with Parkinson's disease. Nucl Med Commun 2001; 22:151-4. [PMID: 11258401 DOI: 10.1097/00006231-200102000-00006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Imaging of dopamine transporters (DATs) in the brain using [99Tcm]TRODAT-1 showed excellent pharmacokinetics for estimation of transporter concentrations. It has been reported that there may be differences in the binding kinetics of DAT radiotracers to DATs between normal subjects and patients with Parkinson's disease (PD). The aim of this study was to determine an optimal time point for (99Tcm]TRODAT-1 brain single photon emission tomography (SPET) acquisition that provides stable target to non-target ratios reflecting the DAT concentration in the brain. Serial [99Tcm]TRODAT-1 brain SPET images 2, 3 and 4 h after intravenous injection of [99Tcm]TRODAT-1 (925 MBq) were performed in five healthy subjects and nine PD patients. Regions of interests were drawn, and caudate/occipital (C/O) and putamen/occipital (P/O) specific to non-specific [99Tcm]TRODAT-1 binding ratios were calculated. The C/O and P/O ratios in healthy subjects showed consistent increases with time, but in PD patients, the C/O and P/O ratios of [99Tcm]TRODAT-1 reached a stable level at 3 h post-injection. There was a statistically significant difference (P < 0.001) between PD and normal subjects at 4 h post-injection for both the C/O and the P/O ratios. In conclusion, we recommend the acquisition of [99Tcm]TRODAT-1 SPET images at 4 h post-injection, as at this time point the C/O and P/O ratios can be used to discriminate between PD patients and healthy subjects.
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Affiliation(s)
- P F Kao
- Department of Nuclear Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
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Lu CS, Wu JC, Tsai CH, Chen RS, Chou YH, Hattori N, Yoshino H, Mizuno Y. Clinical and genetic studies on familial parkinsonism: the first report on a parkin gene mutation in a Taiwanese family. Mov Disord 2001; 16:164-6. [PMID: 11215581 DOI: 10.1002/1531-8257(200101)16:1<164::aid-mds1030>3.0.co;2-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- C S Lu
- First Department of Neurology, Chang Gung Memorial Hospital, Taipei, Taiwan.
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28
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Abstract
We propose a novel multipurpose watermarking scheme, in which robust and fragile watermarks are simultaneously embedded, for copyright protection and content authentication. By quantizing a host image's wavelet coefficients as masking threshold units (MTUs), two complementary watermarks are embedded using cocktail watermarking and they can be blindly extracted without access to the host image. For the purpose of image protection, the new scheme guarantees that, no matter what kind of attack is encountered, at least one watermark can survive well. On the other hand, for the purpose of image authentication, our approach can locate the part of the image that has been tampered with and tolerate some incidental processes that have been executed. Experimental results show that the performance of our multipurpose watermarking scheme is indeed superb in terms of robustness and fragility.
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Affiliation(s)
- C S Lu
- Inst. of Inf. Sci., Acad. Sinica, Taipei.
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29
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Lee CJ, Lee LH, Lu CS, Wu A. Bacterial Polysaccharides as Vaccines — Immunity and Chemical Characterization. The Molecular Immunology of Complex Carbohydrates —2 2001; 491:453-71. [PMID: 14533815 DOI: 10.1007/978-1-4615-1267-7_30] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Studies on protective immunity and biochemical characterization of bacterial capsular polysaccharides have led to significant contributions to understanding of the mechanisms of infectious diseases and development of effective vaccines. Immunity to encapsulated bacteria is related to antibody response to polysaccharide (PS) antigen, interactions with T- and B-lymphocytes, and host defense mechanisms. Meningococcal, pneumococcal and Salmonella vi PSs and Haemophilus type b PS-protein conjugate vaccines have been licensed and provided effective immunity for prevention of these bacterial infections. Capsular PSs are cell-surface polymers consisting of oligosaccharide repeating units. Many PSs are highly polar and hydrophilic and interfere with cell-to-cell interactions with phagocytes. Most pneumococcal PSs are negatively charged and possess acidic components such as D-glucuronic acid and phosphate in phosphodiester bonds. Extensive immunologic cross-reactivity has been observed among bacterial capsular PSs. In infants the antibody responses to most capsular PSs are generally poor. Enhanced immunogenicity of PS antigens can be achieved through PS-protein conjugate vaccines, immunization during a critical period of perinatal development and effective antigen delivery system.
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Affiliation(s)
- C J Lee
- Center for Biologics Evaluation and Research, FDA, Bethesda MD 20817, USA
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30
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Wu JC, Lu CS, Ng SH. Limb myorhythmia in association with hypertrophy of the inferior olive: report of two cases. Chang Gung Med J 2000; 23:630-5. [PMID: 11126156] [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: 02/18/2023]
Abstract
We report on 2 patients who uncommonly developed isolated limb myorhythmia in association with inferior olive hypertrophy (IOH) after an acute stroke in the brain stem. A slow tremor presented in the proximal upper limbs predominantly when at rest. It was aggravated by outstretched arms and by active hand movements. The surface electromyogram (EMG) recorded simultaneous activities over the agonist and antagonist muscles with a rate of 3.5 Hz and 2.5 Hz in 2 patients respectively. In the first patient, bilateral limb myorhythmia presented 12 months after the brain stem stroke, and both inferior olives were hypertrophic. In the second patient, unilateral limb myorhythmia developed in the left hand 7 months after right pontine hemorrhage, and only the right inferior olive was hypertrophic. These findings indicate that limb myorhythmia commencing after brain stem insult is anatomically and temporally related to hypertrophy of the contralateral inferior olive. Based on our 2 patients and previously reported cases, we propose that a possible causal relationship exists between limb myorhythmia and contralateral IOH, although its pathophysiological mechanisms remain to be established. We suggest that, similar to palatal myoclonus, isolated limb myorhythmia is within the clinical spectrum of IOH.
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Affiliation(s)
- J C Wu
- Movement Disorders Unit, Department of Neurology, Chang Gung Memorial Hospital, Taipei, Taiwan, R.O.C.
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31
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Lu CS, Kashima K, Daa T, Yokoyama S, Yanagisawa S, Nakayama I. Immunohistochemical study of the distribution of endogenous biotin and biotin-binding enzymes in ductal structures of salivary gland tumours. J Oral Pathol Med 2000; 29:445-51. [PMID: 11016687 DOI: 10.1034/j.1600-0714.2000.290905.x] [Citation(s) in RCA: 12] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To clarify the pathologic value of endogenous biotin in the salivary gland, we examined in a series of neoplasms of the salivary gland by immunohistochemical staining the distribution of endogenous biotin and of biotin-binding enzymes, namely, acetyl CoA carboxylase (AC), which is a cytosolic enzyme, and pyruvate carboxylase (PC), which is a mitochondrial enzyme. In pleomorphic adenoma, we found biotin and PC in ductal epithelial elements, while AC was found mainly in myoepithelial elements. Carcinoma ex pleomorphic adenoma, adenocarcinoma and mucoepidermoid carcinoma were frequently immunopositive for biotin, PC and AC, while adenoid cystic carcinoma was rarely immunopositive for biotin, PC or AC. These results indicate that endogenous biotin might be associated with the mitochondrial enzyme, which is present at high levels in ductal cells of the salivary gland. However, the neoplastic cells in adenoid cystic carcinoma seemed to have an unusual expression of biotin and related enzymes.
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Affiliation(s)
- C S Lu
- Department of Pathology, Oita Medical University, Japan
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Weng YH, Kao PF, Tsai CH, Yen TC, Lu CS. Dopamine deficiency in rubral tremor caused by midbrain hemangioma: case report. Chang Gung Med J 2000; 23:485-91. [PMID: 11039251] [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: 04/15/2023]
Abstract
To elucidate the nigrostriatal involvement in rubral tremor, we studied single photon emission computed tomography (SPECT) imaging with [2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3.2.1]oct-2- yl]methyl](2-mercaptoethyl)amino]ethyl]amino]ethanethiolato(3-)- N2,N2',S2,S2']oxo-[1R-(exo-exo)]-[99mTc]technetium ([99mTc]TRODAT-1) in a 70-year-old woman with a midbrain hemangioma. She had developed a slow tremor in her right arm and leg after an episode of hemorrhage at the age of 28. The tremor was 3 to 5 Hz in frequency at rest, which was enhanced by outstretching the limb and action. There was no rigidity or bradykinesia. Neurological examination also revealed mild palsy of the left oculomotor nerve. The magnetic resonance imaging (MRI) of the brain showed a small hemangioma in the left midbrain localized mainly in the substantia nigra. The [99mTc]TRODAT-1 SPECT imaging revealed significantly reduced [99mTc]TRODAT-1 uptake in the left caudate and putamen, but it was only mildly reduced in the right striatum. This reduction in uptake was even more severe than that of patients with Parkinson's disease, and indicated that the dopamine function was markedly impaired in the left nigrostriatal system. The tremor had not progressed over the years, and she responded moderately to treatment with levodopa. We concluded that the rubral tremor in the right extremities was probably caused by a dopamine deficiency in the left nigrostriatal system. This suggests that a dopamine deficiency secondary to the midbrain hemangioma might have contributed to the development of the rubral tremor in this patient.
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Affiliation(s)
- Y H Weng
- First Department of Neurology, Chang Gung Memorial Hospital, Taipei, Taiwan, R.O.C
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Abstract
An organic-inorganic hybrid material, poly(methyl methacrylate) (PMMA)-SiO2 (SiO2 content of 72 wt%), was prepared by incorporating PMMA structure units covalently into an SiO2 glass network via the sol-gel approach. The hybrid sol-gel material PMMA-SiO2 was subsequently used as the solid powder component of bone cement and its mechanical properties were evaluated. The effects of the addition of tricalcium phosphate (TCP), hydroxyethyl methacrylate (HEMA), and ethylene glycol dimethacrylate (EGDMA) on the properties of the sol-gel hybrid bone cement were also investigated. The influence of these components on the temperature rise during polymerization was discussed. It was found that the new bone cement containing PMMA-SiO2 hybrid sol-gel material had higher modulus than that of Simplex-P bone cement. The addition of TCP in the new bone cement increased the Young's modulus and the polymerization time; the inverse was observed for the tensile, bending, and compressive strengths, and the polymerization temperature. The addition of HEMA and EGDMA in the new bone cement had the opposite effect of TCP. The comparison between the new sol-gel bone cement and the commercial Simplex P bone cement was discussed.
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Affiliation(s)
- J M Yang
- Department of Chemical Engineering, Chang Gung College of Medicine and Technology, Tao-Yuan, Taiwan, Republic of China
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Yen TC, Lu CS, Tzen KY, Wey SP, Chou YH, Weng YH, Kao PF, Ting G. Decreased dopamine transporter binding in Machado-Joseph disease. J Nucl Med 2000; 41:994-8. [PMID: 10855623] [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: 02/16/2023] Open
Abstract
UNLABELLED The aim of this study was to use 99mTc-TRODAT-1 brain SPECT for investigation of the binding of dopamine transporter (DAT) in the nigrostriatal dopaminergic pathway of symptomatic Machado-Joseph disease (MJD) and to compare the results with the abnormal cytidylate, adenylate, and guanylate (CAG) expansion in the MJD1 gene and other clinical factors. METHODS Ten symptomatic MJD patients (8 women, 2 men; age range, 20-71 y; mean age +/- SD, 36.4 +/- 10.6 y; mean duration of illness, 9.8 +/- 5.4 y) and 21 healthy volunteers (age range, 24-71 y; mean age, 47.6 +/- 20.1 y) were examined. Brain SPECT images were acquired 4 h after injection. The ratio of specific to nonspecific nigrostriatal 99mTc-TRODAT-1 binding was measured and compared with the clinical symptoms, duration of illness, and size of abnormal expanded CAG repeats. RESULTS All nigrostriatal 99mTc-TRODAT-1 ratios were significantly lower in MJD patients than in healthy volunteers (P < 0.05). Discriminant function analysis of all MJD patients showed that the decreased binding of 99mTc-TRODAT-1 in the putamen was not significantly different from that in the caudate nucleus. Eight of 10 MJD patients had significantly decreased 99mTc-TRODAT-1 uptake. Of these 8, 2 had extrapyramidal signs and 6 had no obvious extrapyramidal signs. The other 2 patients, who had normal 99mTc-TRODAT-1 uptake, had no obvious extrapyramidal signs. CONCLUSION Our findings indicate that 99mTc-TRODAT-1 brain SPECT is an appropriate method for evaluating damage to the nigrostriatal DAT in symptomatic MJD patients with and without extrapyramidal signs. The decreased binding of 99mTc-TRODAT-1 in the nigrostriatal dopaminergic pathway in symptomatic MJD patients correlates with the phenotype of extrapyramidal signs but not with the abnormal CAG repeat length, age at disease onset, or disease duration.
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Affiliation(s)
- T C Yen
- Department of Nuclear Medicine, Chang Gung Memorial Hospital, Taipei Medical Center and School of Medicine, Chang Gung University, Taiwan
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Lu CS, Hu CJ, Yu Y, Meng QJ. The inclusion compounds of beta-cyclodextrin with 4-substituted benzoic acid and benzaldehyde drugs studied by proton nuclear magnetic resonance spectroscopy. Chem Pharm Bull (Tokyo) 2000; 48:56-9. [PMID: 10705476 DOI: 10.1248/cpb.48.56] [Citation(s) in RCA: 16] [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: 11/22/2022]
Abstract
Inclusion compounds of some 4-substituted benzoic acid and benzaldehyde drugs with beta-cyclodextrin were prepared and characterized by IR spectroscopy, powder X-ray diffraction, thermogravimetry, and 1H-NMR spectroscopy. The thermal stability and chemical stability of these drugs were strikingly improved after inclusion. The effect of inclusion on the chemical-shifts of protons H-3 and H-5 in the NMR spectroscopy is discussed. Using the relative shift theory, the preferred inclusion mode was proposed. The center of the aromatic ring of the drug molecule was considered to be located in the cavity 1.2 A inside from the H-5 plane of beta-cyclodextrin.
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Affiliation(s)
- C S Lu
- Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing University, P. R. China
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36
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Abstract
Dynamic and flow-through flux chambers are convenient tools for field measurements of gas or VOC emission flux from solid surfaces in the field. This study was undertaken to collect on site and quantify the emissions of volatile organic compounds (VOCs) released from athletic running tracks. Three typical types of tracks, one synthetic rubber and two tracks (types I and II) consisting mainly of polyurethane, were studied. They were all installed with adhesives and backings, both of which contributed significant amount of VOCs. VOCs released from the track surface were collected with a flux chamber and subsequently analyzed by a gas chromatograph/mass spectrometer (GC/MS). Also, for each track and at each selected time the emission flux and mass emission were measured on site under outdoor conditions over a period of 40 min. GC/MS analyses show that the VOCs emitted include 2-methyl furan, butanal, methyl ethyl ketone, benzene, heptane, methyl isobutyl ketone, toluene+octane, hexanal, nonane+ethylbenzene, xylenes+styrene, propyl benzene, decane, 1,3,5-trimethyl benzene, 1,2,4-trimethyl benzene, 1,2, 3-trimethyl benzene and undecane. Of these, hexanal was the common and principal compound for all three types of tracks. 2-Methyl furan and methyl isobutyl ketone were the characteristic compounds for the synthetic rubber and the type II of polyurethane tracks, respectively. In the field studies, no unique compounds were found in the type I of polyurethane tracks. For each of these three types of tracks the total-VOCs emission flux was correlated to the track age and track surface temperature. The results of multiple regression analysis showed good correlation. The type II polyurethane track had the highest decay rate, while the synthetic rubber track had the lowest decay rate. Two years after the track installation, the VOC concentrations measured at 1.5 m above the track, the breathing height of school children, were not significantly higher than the background levels.
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Affiliation(s)
- F H Chang
- Department of Environmental Engineering, National Cheng Kung University, Tainan, Taiwan
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Abstract
We reviewed the magnetic resonance imaging scans from 22 serial studies of 5 patients with Balò's concentric sclerosis collected during the past 3 years. The data showed the concentric lesions did not occur simultaneously but developed step by step in a centrifugal direction. The development of lesions was preceded by an enhancing ring relatively devoid of demyelination and was followed by progressive demyelination occurring mainly at the inner aspect of the enhancement. The same process recurred on the edge of the previous enhanced zone. Thus, an appearance of concentric rings with alternating demyelinated and relatively myelin-preserved bands was formed.
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Affiliation(s)
- C J Chen
- Department of Diagnostic Radiology, Chang Gung Memorial Hospital and University, Taipei, Taiwan
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38
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Abstract
Ramsay Hunt syndrome (RHS) is a rare condition within the progressive myoclonic epilepsies syndrome (PME), with a triad of action myoclonus, grand mal seizure and severe cerebellar ataxia. There are few reports about the psychiatric disturbances associated with PME or RHS. The present study examines the evidence that RHS may accompany an organic mental syndrome, ethanol's effective suppression of myoclonus, and the possible resultant problem of alcohol dependence in RHS patients. Two brothers with the previous long-standing diagnosis of RHS and their mental symptoms of persecutory delusion and depression are reported, as well as the additional problem of alcohol dependence in one of them. The cerebellar dysfunction found in RHS may be associated with an underlying organic condition. Determination of the relationship between cerebellar dysfunction and psychosis in RHS will require further study. Although the mechanism of the suppression of myoclonus by alcohol remains unclear, patients should be allowed to drink socially, and alcohol consumption should not be totally prohibited. However, effective treatment of the problems of alcohol tolerance, abuse, or dependence requires the cooperation of both neurologists and psychiatrists.
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Affiliation(s)
- M C Hsiao
- Department of Psychiatry, Chang Gung Memorial Hospital, Tao-yuan, Taiwan
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39
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Abstract
We reviewed the magnetic resonance imaging scans from 22 serial studies of 5 patients with Balò's concentric sclerosis collected during the past 3 years. The data showed the concentric lesions did not occur simultaneously but developed step by step in a centrifugal direction. The development of lesions was preceded by an enhancing ring relatively devoid of demyelination and was followed by progressive demyelination occurring mainly at the inner aspect of the enhancement. The same process recurred on the edge of the previous enhanced zone. Thus, an appearance of concentric rings with alternating demyelinated and relatively myelin-preserved bands was formed.
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Affiliation(s)
- C J Chen
- Department of Diagnostic Radiology, Chang Gung Memorial Hospital and University, Taipei, Taiwan
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Lin SL, Shih SR, Hung YB, Lin CY, Lu CS. Intussusception in a child infected with enterovirus: case report. Changgeng Yi Xue Za Zhi 1999; 22:319-23. [PMID: 10493041] [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: 02/14/2023]
Abstract
Most intussusceptions in childhood are idiopathic. The association of viral infection has been suspected for decades. We report a case of ileocolonic intussusception in a child during a course of enterovirus infection. A 20-month-old girl with vomiting and irritable crying of 4 days' duration was found to have intussusception by sonography. She had suffered from herpangina one week earlier. Due to her peritoneal signs, she underwent surgical manual reduction. A cluster of enlarged lymph nodes in the intussuscipiens was noted preoperatively by high resolution ultrasound. Two swollen lymph nodes were removed for pathologic evaluation and examined for a viral genome by polymerase chain reaction (PCR) amplification. Panenterovirus base pairs were confirmed on the electrophoresis print. During postoperative sonographic follow-up, significant shrinkage of previous mesenteric lymphoid hyperplasia was observed. In this article, we present the first case of childhood intussusception in associated with enterovirus infection, in which the panenterovirus genome was identified in the patient's mesenteric lymph nodes. This was also the first evaluation of the role of mesenteric lymph nodes in intussusception by high resolution sonography.
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Affiliation(s)
- S L Lin
- Department of Pediatrics, Chang Gung Memorial Hospital, Keelung, Taiwan, R.O.C
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41
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Lin SL, Lee CM, Kong MS, Lu CS, You CM. Congenital hepatic arterioportal fistula complicated with gastrointestinal bleeding treated with transcatheter embolization: case report. Changgeng Yi Xue Za Zhi 1999; 22:106-10. [PMID: 10418218] [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: 02/13/2023]
Abstract
Congenital hepatic arterioportal fistula (HAVF) is extremely rare in children. We present a patient with congenital hepaticoportal arteriovenous fistula complicated with gastrointestinal bleeding treated using transcatheter arterial embolization. Our patient was the youngest (2 days old) case ever reported with congenital HAVF and the first one to receive arterial embolization for HAVF during childhood. The 3-year-old girl was suggested of having congenital HAVF using Doppler ultrasonography. However, her family refused further investigation, and she was lost to follow-up. Three years later, she was sent to our hospital due to melaena. Repeated ultrasonography revealed dilated intrahepatic portal vein with arterial flow demonstrated using Doppler imaging. No esophageal varices or gastric or duodenal ulcer was seen during endoscopy. Angiography showed a HAVF and transcatheter embolization was done simultaneously. Follow-up at one and two weeks post-embolization revealed no more shunt flow within the portal vein, though cystic like dilatation of the portal vein persisted, and no thrombosis was observed. This case emphasizes that transcatheter arterial embolization can be easily and successfully used for treating childhood congenital HAVF. Abnormal dilatation of the portal vein in children needs doppler evaluation and possibly angiography.
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Affiliation(s)
- S L Lin
- Department of Pediatrics, Chang Gung Memorial Hospital, Keelung, Taiwan, R.O.C
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Abstract
INTRODUCTION We compared the clinical manifestations and response to medications between familial and sporadic patients with paroxysmal kinesigenic dyskinesia (PKD), and also between patients with autosomal dominant (AD) and autosomal recessive (AR) inheritance. MATERIAL AND METHODS This retrospective cohort study included 9 familial and 11 sporadic Taiwanese patients with PKD diagnosed during a 10-year period at one of two hospitals. The mean duration of follow-up was 3.8 +/- 2.7 years. Each patient was interviewed and their medical records, as well as videotape recordings of PKD attacks in 6 patients, were used for analysis. Patients were treated with either carbamazepine or phenytoin, and the efficacy of sodium valproate was tested in 5 patients. RESULTS No single distinguishing feature in terms of clinical manifestations or therapeutic response was found to differentiate among familial, and sporadic cases, or between AD and AR inheritance. Carbamazepine and phenytoin were superior to sodium valproate in treating both familial and sporadic PKD patients, and both drugs resulted in almost complete remission of attacks. CONCLUSION Our findings indicate that the sporadic and familiar forms of PKD, as well as the AR and AD inherited types, are similar in terms of clinical manifestations and response to treatment. The functional status and prognosis of our Taiwanese patients suggest that PKD is a relatively benign entity.
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Affiliation(s)
- W J Hwang
- Department of Neurology, National Cheng Kung University Hospital, Tainan, Taiwan
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Liu CY, Yu JM, Wang NM, Chen RS, Chang HC, Li HY, Tsai CH, Yang YY, Lu CS. Emotional symptoms are secondary to the voice disorder in patients with spasmodic dysphonia. Gen Hosp Psychiatry 1998; 20:255-9. [PMID: 9719906 DOI: 10.1016/s0163-8343(98)00022-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The aims of this study were to evaluate the emotional status and life quality of the patients with spasmodic dysphonia (SD) before and after botulinum toxin treatment, and to ascertain whether SD is a somatoform disorder. Ten patients with spasmodic dysphonia were injected unilaterally into the vocal cord with botulinum toxin. Before botulinum toxin treatment, two clinician's rating scales--Hamilton Depression Rating Scale (HDRS) and Hamilton Anxiety Rating Scale (HARS), and three self-rating psychometrics--Zung's Self-Rating Depression Scale (SDS), Life Quality Scale (GHQ/QL-12), and Symptom Distress Checklist (SCL-90) were applied. Self-rating scales were also administered in 20 matched normal controls. The patients were reevaluated 1 month after botulinum toxin treatment. The Clinical Global Impression Scale (CGI) was also rated by the patients themselves and a speech pathologist. The mean scores of SD patients were significantly higher than that of controls in SDS, and subscales of somatization, obsessive-compulsive symptoms, depression, anxiety, and psychoticism in SCL-90. The mean score of GHQ/QL-12 was significantly higher in the control group. The scores of HDRS, SDS, GHQ/QL-12 and subscales of somatization, depression, and anxiety in SCL-90 showed significant improvement after botulinum treatment. In CGI, seven patients were rated as improved by patients themselves and the speech pathologist. The patients with SD had more anxiety, depression and somatization symptoms, and poor life quality than normal controls. Their emotional status and life quality improved after botulinum toxin treatment. The results suggest that the emotional symptoms of patients with SD are mainly secondary to voice disorder.
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Affiliation(s)
- C Y Liu
- Department of Psychiatry, Chang Gung University School of Medicine, Taoyuan, Taiwan, R.O.C
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Abstract
We studied the long-term clinical course of five patients with chronic manganese intoxication. The mean scores of the King's College Hospital Rating Scale for Parkinson's disease increased from 15.0 +/- 4.2 in 1987 to 28.3 +/- 6.70 in 1991 and then to 38.1 +/- 12.9 in 1995. The deterioration was most prominent in gait, rigidity, speed of foot tapping, and writing. Tissue concentrations of manganese in blood, urine, scalp hair, and pubic hair returned to normal. Follow-up MRIs did not show paramagnetic high-signal intensity on T1-weighted images. The data indicate that clinical progression in patients with manganese parkinsonism continues even 10 years after cessation of exposure.
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Affiliation(s)
- C C Huang
- Department of Neurology, Chang Gung Memorial Hospital and Medical College, Taipei, Taiwan
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45
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Lu CS, Ikeda A, Terada K, Mima T, Nagamine T, Fukuyama H, Kohara N, Kojima Y, Yonekura Y, Chen RS, Tsai CH, Chu NS, Kimura J, Shibasaki H. Electrophysiological studies of early stage corticobasal degeneration. Mov Disord 1998; 13:140-6. [PMID: 9452339 DOI: 10.1002/mds.870130126] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We conducted electrophysiological studies in two Asian patients with probable corticobasal degeneration (CBD). The duration of illness from onset was 16 and 20 months, respectively. The clinical manifestations were markedly asymmetric and characterized by cortical sensory loss, apraxia, action myoclonus, action tremor, and akinetic-rigid parkinsonism. Neither patient responded to levodopa therapy. Simple photon-emission computed tomography (SPECT) study showed significantly decreased regional cerebral blood flow in the frontoparietal areas and thalamus opposite to the predominantly affected limb. A series of electrophysiological studies failed to identify giant somatosensory evoked potentials (SEPs), enhanced long latency electromyography (EMG) reflex, and cortical spikes preceding myoclonic jerk. However, the earliest cortical component of the median nerve SEP was exclusively enlarged in one patient and preserved with depression of the subsequent components in the other patient. Significantly shorter postmotor-evoked potential (MEP) silent period was found after the transcranial magnetic stimulation of the motor cortex in both patients. CBD is a unique clinical entity characterized by action myoclonus probably the result of the pathologic hyperexcitability of the motor cortex, based on a loss of inhibitory input from the sensory cortex.
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Affiliation(s)
- C S Lu
- Department of Neurology, Chang Gung Medical College and Memorial Hospital, Taipei, Taiwan
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Hwang WL, Lu CS, Chung PC. Shape from texture: estimation of planar surface orientation through the ridge surfaces of continuous wavelet transform. IEEE Trans Image Process 1998; 7:773-780. [PMID: 18276291 DOI: 10.1109/83.668032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this correspondence, a method is proposed for estimating the surface orientation of a planar texture under perspective projection based on the ridge of a two-dimensional (2-D) continuous wavelet transform (CWT). We show that an analytical solution of the surface orientation can be derived from the scales of the ridge surface. A comparative study with an existing method is given.
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Affiliation(s)
- C C Huang
- Department of Neurology, Chang Gung Memorial Hospital, Taipei, Taiwan
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Lu CS, Chiu CH, Lin TY, Lin SL. Salmonella typhimurium brain abscess in a six-month-old infant: a case report and review of the literature. Changgeng Yi Xue Za Zhi 1997; 20:219-25. [PMID: 9397614] [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: 02/05/2023]
Abstract
We report the case of a six-month-old male infant with brain abscess caused by Salmonella typhimurium. Upon admission, he was suffering from fever, diarrhea, drowsiness and convulsion. Salmonella meningitis was identified by CSF examination. Following failure of antibiotic therapy to control his fever, brain computerized tomography (CT) was ordered 5 days later and revealed a brain abscess. He received surgical excision of the abscess and recovered completely after receiving ceftriaxone therapy for 8 weeks. The case of our patient, together with 11 cases of Salmonella brain abscess from the English literature are reviewed. There was a male preponderance among these patients (male: female = 2.67 : 1) and the majority were less than one year old. Salmonella typhimurium, typhi, and enteritidis occurred most frequently. Fever, seizure, signs and symptoms of increased intracranial pressure and change in mental status were the most common clinical features. Purulent meningitis was a major predisposing factor. Successful treatment was associated with early identification, prompt surgical intervention, high dose, long-term antibiotic therapy, and close follow-up for possible recurrence and to determine the presence of neurological sequelae.
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Affiliation(s)
- C S Lu
- Department of Pediatrics, Chang Gung Children's Hospital, Taoyuan, Taiwan, R.O.C
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Abstract
The aim of this study was to compare the wear of seven different restorative materials using two different wear simulation modes. This included a non-impact sliding wear test (rotary pin and disc) and an impact-cum-sliding wear test (masticatory simulator). The difference in wear ranking between the two wear tests was compared as well as the correlation of wear to the hardness of the materials. Hardness ranking in the order of decreasing hardness was as follows: Dispersalloy (DA), P50 (P50), Hi-Dense (HD), TPH (TPH), Fuji II LC (FJ), Dyract (DR) and Vitremer (VM). For volumetric wear using the non-impact sliding test, the following ranking in the order of decreasing wear resistance was obtained: DA, TPH, DR, HD, VM, FJ, P50. The results for volumetric wear with impact-cum-sliding wear testing in the order of decreasing wear resistance were: TPH, DR, P50, AR, FJ, VM, HD. Results showed that there is no correlation between hardness and wear resistance. There is also no correlation between impact-cum-sliding wear and non-impact sliding wear. Impact wear should be considered in future two-body wear assessment of materials.
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Affiliation(s)
- A U Yap
- Department of Restorative Dentistry, Faculty of Dentistry, National University of Singapore
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Affiliation(s)
- C H Tsai
- Department of Neurology, Chang Chang Memorial Hospital, Taipei, Taiwan
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