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Lai TY, Chiang TC, Lee CY, Kuo TC, Wu CH, Chen YI, Hu CM, Maskey M, Tang SC, Jeng YM, Tien YW, Lee EYHP, Lee WH. Unraveling the impact of cancer-associated fibroblasts on hypovascular pancreatic neuroendocrine tumors. Br J Cancer 2024; 130:1096-1108. [PMID: 38341509 PMCID: PMC10991442 DOI: 10.1038/s41416-023-02565-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 12/11/2023] [Accepted: 12/19/2023] [Indexed: 02/12/2024] Open
Abstract
BACKGROUND Pancreatic neuroendocrine tumors (PNETs) with low microvessel density and fibrosis often exhibit clinical aggressiveness. Given the contribution of cancer-associated fibroblasts (CAFs) to the hypovascular fibrotic stroma in pancreatic ductal adenocarcinoma, investigating whether CAFs play a similar role in PNETs becomes imperative. In this study, we investigated the involvement of CAFs in PNETs and their effects on clinical outcomes. METHODS We examined 79 clinical PNET specimens to evaluate the number and spatial distribution of α-smooth muscle actin (SMA)-positive cells, which are indicative of CAFs. Then, the findings were correlated with clinical outcomes. In vitro and in vivo experiments were conducted to assess the effects of CAFs (isolated from clinical specimens) on PNET metastasis and growth. Additionally, the role of the stromal-cell-derived factor 1 (SDF1)-AGR2 axis in mediating communication between CAFs and PNET cells was investigated. RESULTS αSMA-positive and platelet-derived growth factor-α-positive CAFs were detected in the hypovascular stroma of PNET specimens. A higher abundance of α-SMA-positive CAFs within the PNET stroma was significantly associated with a higher level of clinical aggressiveness. Notably, conditioned medium from PNET cells induced an inflammatory phenotype in isolated CAFs. These CAFs promoted PNET growth and metastasis. Mechanistically, PNET cells secreted interleukin-1, which induced the secretion of SDF1 from CAFs. This cascade subsequently elevated AGR2 expression in PNETs, thereby promoting tumor growth and metastasis. The downregulation of AGR2 in PNET cells effectively suppressed the CAF-mediated promotion of PNET growth and metastasis. CONCLUSION CAFs drive the growth and metastasis of aggressive PNETs. The CXCR4-SDF1 axis may be a target for antistromal therapy in the treatment of PNET. This study clarifies mechanisms underlying PNET aggressiveness and may guide future therapeutic interventions targeting the tumor microenvironment.
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Affiliation(s)
- Ting-Yu Lai
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Tsai-Chen Chiang
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Ting-Chun Kuo
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Chien-Hui Wu
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Yi-Ing Chen
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Chun-Mei Hu
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Manjit Maskey
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USA
| | - Shiue-Cheng Tang
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Yung-Ming Jeng
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Wen Tien
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.
| | - Eva Y-H P Lee
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
- Department of Biological Chemistry, University of California, Irvine, CA, USA
| | - Wen-Hwa Lee
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
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Lin CY, Wang CC, Loh JZ, Chiang TC, Weng TI, Chan DC, Hung KY, Chiang CK, Liu SH. Therapeutic Ultrasound Halts Progression of Chronic Kidney Disease In Vivo via the Regulation of Markers Associated with Renal Epithelial-Mesenchymal Transition and Senescence. Int J Mol Sci 2022; 23:13387. [PMID: 36362179 PMCID: PMC9654276 DOI: 10.3390/ijms232113387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 10/29/2022] [Accepted: 11/01/2022] [Indexed: 08/30/2023] Open
Abstract
Low-intensity pulsed ultrasound (LIPUS), a therapeutic type of ultrasound, is known to enhance bone fracture repair processes and help some tissues to heal. Here, we investigated the therapeutic potential of LIPUS for the treatment of chronic kidney disease (CKD) in two CKD mouse models. CKD mice were induced using both unilateral renal ischemia/reperfusion injury (IRI) with nephrectomy and adenine administration. The left kidneys of the CKD mice were treated using LIPUS with the parameters of 3 MHz, 100 mW/cm2, and 20 min/day, based on the preliminary experiments. The mice were euthanized 14 days after IRI or 28 days after the end of adenine administration. LIPUS treatment effectively alleviated the decreases in the body weight and albumin/globulin ratio and the increases in the serum renal functional markers, fibroblast growth factor-23, renal pathological changes, and renal fibrosis in the CKD mice. The parameters for epithelial-mesenchymal transition (EMT), senescence-related signal induction, and the inhibition of α-Klotho and endogenous antioxidant enzyme protein expression in the kidneys of the CKD mice were also significantly alleviated by LIPUS. These results suggest that LIPUS treatment reduces CKD progression through the inhibition of EMT and senescence-related signals. The application of LIPUS may be an alternative non-invasive therapeutic intervention for CKD therapy.
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Affiliation(s)
- Chen-Yu Lin
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Ching-Chia Wang
- Department of Pediatrics, National Taiwan University Hospital, Taipei 100, Taiwan
| | - Jui-Zhi Loh
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Tsai-Chen Chiang
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Te-I Weng
- Department of Forensic Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Ding-Cheng Chan
- Department of Geriatrics and Gerontology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Kuan-Yu Hung
- Department of Internal Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Chih-Kang Chiang
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
- Departments of Integrated Diagnostics & Therapeutics and Internal Medicine, College of Medicine and Hospital, National Taiwan University, Taipei 100, Taiwan
| | - Shing-Hwa Liu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
- Department of Pediatrics, National Taiwan University Hospital, Taipei 100, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 404, Taiwan
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Chung MH, Chien HJ, Peng SJ, Chou YH, Chiang TC, Chang HP, Lee CY, Chen CC, Jeng YM, Tien YW, Tang SC. Multimodal 3-D/2-D human islet and duct imaging in exocrine and endocrine lesion environment: associated pancreas tissue remodeling. Am J Physiol Endocrinol Metab 2022; 323:E354-E365. [PMID: 35947703 DOI: 10.1152/ajpendo.00111.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pancreatic intraepithelial neoplasia (PanIN) and islet cell microadenoma are exocrine and endocrine neoplasms of human pancreas that have been linked to pancreatic ductal adenocarcinoma (PDAC) and neuroendocrine tumor, respectively. However, in health and at the surgical margin of pancreatic cancer, it remains unresolved how to simultaneously characterize duct and islet remodeling to investigate the exocrine-endocrine association in the lesion microenvironment. Here, we develop a new vibratome-based approach to detect, confirm, and analyze the two types of pancreas remodeling via stereo/three-dimensional (3-D) and classic/two-dimensional (2-D) histology. Surgical margins of PDAC (n = 10, distal) and cadaveric donor pancreases (n = 10, consecutive cases) were fixed, sectioned by vibratome (350 µm), and surveyed for PanIN and microadenoma via stereomicroscopy. After lesion detection, PanIN and microadenoma were analyzed with 3-D fluorescence imaging and clinical microtome-based histology for confirmation and assessment of microenvironment. Multimodal imaging of PDAC surgical margins and cadaveric donor pancreases detected the peri-PanIN islet aggregation with duct-islet cell clusters. Organ-wide survey of cadaveric donor pancreases shows a marked 2.3-fold increase in the lesion size with the PanIN-islet association vs. without the association. In the survey, we unexpectedly detected the islet cell microadenoma adjacent to (<2 mm) PanIN. Overall, among the 53 early lesions in the cadaveric donor pancreases (PanINs and microadenomas), 81% are featured with the associated exocrine-endocrine tissue remodeling. Multimodal 3-D/2-D tissue imaging reveals local and simultaneous duct and islet remodeling in the cancer surgical margin and cadaveric donor pancreas. In the cadaveric donor pancreas, the peri-PanIN islet aggregation and PanIN-microadenoma association are two major features of pancreas remodeling in the early lesion microenvironment.NEW & NOTEWORTHY We develop a new multimodal 3-D/2-D imaging approach (matched stereomicroscopic, fluorescence, and H&E signals) to examine human duct-islet association in the PDAC surgical margin and cadaveric donor pancreas. In both conditions, peri-PanIN islet aggregation with duct-islet cell clusters was identified. The PanIN-islet cell microadenoma association was unexpectedly detected in the donor pancreas. Our work provides the technical and morphological foundations to simultaneously characterize human islets and ducts to study their association in health and disease.
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Affiliation(s)
- Mei-Hsin Chung
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Department of Pathology, National Taiwan University Hospital-Hsinchu Branch, Hsinchu, Taiwan
| | - Hung-Jen Chien
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Shih-Jung Peng
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ya-Hsien Chou
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Tsai-Chen Chiang
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Hsiu-Pi Chang
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Chien-Chia Chen
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Yung-Ming Jeng
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Wen Tien
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shiue-Cheng Tang
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
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Tien YW, Chien HJ, Chiang TC, Chung MH, Lee CY, Peng SJ, Chen CC, Chou YH, Hsiao FT, Jeng YM, Tang SC. Local islet remodelling associated with duct lesion-islet complex in adult human pancreas. Diabetologia 2021; 64:2266-2278. [PMID: 34272581 DOI: 10.1007/s00125-021-05504-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 03/19/2021] [Indexed: 12/13/2022]
Abstract
AIMS/HYPOTHESIS Islets are thought to be stably present in the adult human pancreas to maintain glucose homeostasis. However, identification of the pancreatic intraepithelial neoplasia (PanIN)-islet complex in mice and the presence of PanIN lesions in adult humans suggest that similar remodelling of islet structure and environment may occur in the human pancreas. To identify islet remodelling in a clinically related setting, we examine human donor pancreases with 3D histology to detect and characterise the human PanIN-islet complex. METHODS Cadaveric donor pancreases (26-65 years old, n = 10) were fixed and sectioned (350 μm) for tissue labelling, clearing and microscopy to detect local islet remodelling for 3D analysis of the microenvironment. The remodelled microenvironment was subsequently examined via microtome-based histology for clinical assessment. RESULTS In nine pancreases, we identified the unique peri-lobular islet aggregation associated with the PanIN lesion (16 lesion-islet complexes detected; size: 3.18 ± 1.34 mm). Important features of the lesion-islet microenvironment include: (1) formation of intra-islet ducts, (2) acinar atrophy, (3) adipocyte association, (4) inflammation (CD45+), (5) stromal accumulation (α-SMA+), (6) increase in Ki-67 proliferation index but absence of Ki-67+ alpha/beta cells and (7) in-depth and continuous duct-islet cell contacts, forming a cluster. The duct-islet cell cluster and intra-islet ducts suggest likely islet cell neogenesis but not replication. CONCLUSIONS/INTERPRETATION We identify local islet remodelling associated with PanIN-islet complex in the adult human pancreas. The tissue remodelling and the evidence of inflammation and stromal accumulation suggest that the PanIN-islet complex is derived from tissue repair after a local injury.
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Affiliation(s)
- Yu-Wen Tien
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Hung-Jen Chien
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Tsai-Chen Chiang
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Mei-Hsin Chung
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Department of Pathology, National Taiwan University Hospital - Hsinchu Branch, Hsinchu, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Jung Peng
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chien-Chia Chen
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Ya-Hsien Chou
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Fu-Ting Hsiao
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Yung-Ming Jeng
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Shiue-Cheng Tang
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan.
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Huang SS, Lee KJ, Chen HC, Prajnamitra RP, Hsu CH, Jian CB, Yu XE, Chueh DY, Kuo CW, Chiang TC, Choong OK, Huang SC, Beh CY, Chen LL, Lai JJ, Chen P, Kamp TJ, Tien YW, Lee HM, Hsieh PCH. Immune cell shuttle for precise delivery of nanotherapeutics for heart disease and cancer. Sci Adv 2021; 7:7/17/eabf2400. [PMID: 33893103 PMCID: PMC8064633 DOI: 10.1126/sciadv.abf2400] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 03/05/2021] [Indexed: 05/05/2023]
Abstract
The delivery of therapeutics through the circulatory system is one of the least arduous and less invasive interventions; however, this approach is hampered by low vascular density or permeability. In this study, by exploiting the ability of monocytes to actively penetrate into diseased sites, we designed aptamer-based lipid nanovectors that actively bind onto the surface of monocytes and are released upon reaching the diseased sites. Our method was thoroughly assessed through treating two of the top causes of death in the world, cardiac ischemia-reperfusion injury and pancreatic ductal adenocarcinoma with or without liver metastasis, and showed a significant increase in survival and healing with no toxicity to the liver and kidneys in either case, indicating the success and ubiquity of our platform. We believe that this system provides a new therapeutic method, which can potentially be adapted to treat a myriad of diseases that involve monocyte recruitment in their pathophysiology.
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Affiliation(s)
- San-Shan Huang
- Ph.D. Program in Translational Medicine, National Taiwan University and Academia Sinica, Taipei, Taiwan
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Keng-Jung Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Hung-Chih Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | | | - Chia-Hsin Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Cheng-Bang Jian
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
- Department of Chemistry, National Taiwan University, Taipei 115, Taiwan
- Nano Science and Technology Program, Taiwan International Graduate Program, Academia Sinica and National Taiwan University, Taipei, Taiwan
| | - Xu-En Yu
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
- Department of Chemistry, National Central University, Chung-Li 32001, Taiwan
| | - Di-Yen Chueh
- Research Center for Applied Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Chiung Wen Kuo
- Research Center for Applied Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Tsai-Chen Chiang
- Department of Surgery, National Taiwan University and Hospital, Taipei 100, Taiwan
| | - Oi Kuan Choong
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Shao-Chan Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Chaw Yee Beh
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Li-Lun Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - James J Lai
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Peilin Chen
- Research Center for Applied Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Timothy J Kamp
- Department of Medicine and Stem Cell and Regenerative Medicine Center, University of Wisconsin, Madison, WI 53705, USA
| | - Yu-Wen Tien
- Department of Surgery, National Taiwan University and Hospital, Taipei 100, Taiwan
| | - Hsien-Ming Lee
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Patrick Ching-Ho Hsieh
- Ph.D. Program in Translational Medicine, National Taiwan University and Academia Sinica, Taipei, Taiwan.
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
- Department of Medicine and Stem Cell and Regenerative Medicine Center, University of Wisconsin, Madison, WI 53705, USA
- Institute of Medical Genomics and Proteomics and Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei 100, Taiwan
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Chen KJ, Chiang TC, Yu CJ, Lee FJS. Cooperative recruitment of Arl4A and Pak1 to the plasma membrane contributes to sustained Pak1 activation for cell migration. J Cell Sci 2020; 133:jcs233361. [PMID: 31932503 DOI: 10.1242/jcs.233361] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 12/17/2019] [Indexed: 01/27/2023] Open
Abstract
Cell migration requires the coordination of multiple signaling pathways involved in membrane dynamics and cytoskeletal rearrangement. The Arf-like small GTPase Arl4A has been shown to modulate actin cytoskeleton remodeling. However, evidence of the function of Arl4A in cell migration is insufficient. Here, we report that Arl4A acts with the serine/threonine protein kinase Pak1 to modulate cell migration through their cooperative recruitment to the plasma membrane. We first observed that Arl4A and its isoform Arl4D interact with Pak1 and Pak2 and showed that Arl4A recruits Pak1 and Pak2 to the plasma membrane. The fibronectin-induced Pak1 localization at the plasma membrane is reduced in Arl4A-depleted cells. Unexpectedly, we found that Pak1, but not Arl4A-binding-defective Pak1, can recruit a cytoplasmic myristoylation-deficient Arl4A-G2A mutant to the plasma membrane. Furthermore, we found that the Arl4A-Pak1 interaction, which is independent of Rac1 binding to Pak1, is required for Arl4A-induced cell migration. Thus, we infer that there is feedback regulation between Arl4A and Pak1, in which they mutually recruit each other to the plasma membrane for Pak1 activation, thereby modulating cell migration through direct interaction.
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Affiliation(s)
- Kuan-Jung Chen
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei 10002, Taiwan
| | - Tsai-Chen Chiang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei 10002, Taiwan
| | - Chia-Jung Yu
- Department of Cell and Molecular Biology, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan
- Department of Thoracic Medicine, Chang Gung Memorial Hospital, Linkou, Taoyuan 33305, Taiwan
| | - Fang-Jen S Lee
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei 10002, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
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Chien HJ, Chiang TC, Peng SJ, Chung MH, Chou YH, Lee CY, Jeng YM, Tien YW, Tang SC. Human pancreatic afferent and efferent nerves: mapping and 3-D illustration of exocrine, endocrine, and adipose innervation. Am J Physiol Gastrointest Liver Physiol 2019; 317:G694-G706. [PMID: 31509431 DOI: 10.1152/ajpgi.00116.2019] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The pancreas consists of both the exocrine (acini and ducts) and endocrine (islets) compartments to participate in and regulate the body's digestive and metabolic activities. These activities are subjected to neural modulation, but characterization of the human pancreatic afferent and efferent nerves remains difficult because of the lack of three-dimensional (3-D) image data. Here we prepare transparent human donor pancreases for 3-D histology to reveal the pancreatic microstructure, vasculature, and innervation in a global and integrated fashion. The pancreatic neural network consists of the substance P (SP)-positive sensory (afferent) nerves, the vesicular acetylcholine transporter (VAChT)-positive parasympathetic (efferent) nerves, and the tyrosine hydroxylase (TH)-positive sympathetic (efferent) nerves. The SP+ afferent nerves were found residing along the basal domain of the interlobular ducts. The VAChT+ and TH+ efferent nerves were identified at the peri-acinar and perivascular spaces, which follow the blood vessels to the islets. In the intrapancreatic ganglia, the SP+ (scattered minority, ~7%) and VAChT+ neurons co-localize, suggesting a local afferent-efferent interaction. Compared with the mouse pancreas, the human pancreas differs in 1) the lack of SP+ afferent nerves in the islet, 2) the lower ganglionic density, and 3) the obvious presence of VAChT+ and TH+ nerves around the intralobular adipocytes. The latter implicates the neural influence on the pancreatic steatosis. Overall, our 3-D image data reveal the human pancreatic afferent and efferent innervation patterns and provide the anatomical foundation for future high-definition analyses of neural remodeling in human pancreatic diseases.NEW & NOTEWORTHY Modern three-dimensional (3-D) histology with multiplex optical signals identifies the afferent and efferent innervation patterns of human pancreas, which otherwise cannot be defined with standard histology. Our 3-D image data reveal the unexpected association of sensory and parasympathetic nerves/neurons in the intrapancreatic ganglia and identify the sympathetic and parasympathetic nerve contacts with the infiltrated adipocytes. The multiplex approach offers a new way to characterize the human pancreas in remodeling (e.g., fatty infiltration and duct lesion progression).
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Affiliation(s)
- Hung-Jen Chien
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Tsai-Chen Chiang
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Jung Peng
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Mei-Hsin Chung
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Pathology, National Taiwan University Hospital-Hsinchu Branch, Hsinchu, Taiwan
| | - Ya-Hsien Chou
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Yung-Ming Jeng
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Wen Tien
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Shiue-Cheng Tang
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
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Shen CN, Goh KS, Huang CR, Chiang TC, Lee CY, Jeng YM, Peng SJ, Chien HJ, Chung MH, Chou YH, Hsieh CC, Kulkarni S, Pasricha PJ, Tien YW, Tang SC. Lymphatic vessel remodeling and invasion in pancreatic cancer progression. EBioMedicine 2019; 47:98-113. [PMID: 31495721 PMCID: PMC6796580 DOI: 10.1016/j.ebiom.2019.08.044] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 08/15/2019] [Accepted: 08/15/2019] [Indexed: 12/11/2022] Open
Abstract
Background The lymphatic system is involved in metastasis in pancreatic cancer progression. In cancer staging, lymphatic spread has been used to assess the invasiveness of tumor cells. However, from the endothelium's perspective, the analysis downplays the peri-lesional activities of lymphatic vessels. This unintended bias is largely due to the lack of 3-dimensional (3-D) tissue information to depict the lesion microstructure and vasculature in a global and integrated fashion. Methods We targeted the pancreas as the model organ to investigate lymphatic vessel remodeling in cancer lesion progression. Transparent pancreases were prepared by tissue clearing to facilitate deep-tissue, tile-scanning microscopy for 3-D lymphatic network imaging. Findings In human pancreatic ductal adenocarcinoma, we identify the close association between the pancreatic intraepithelial neoplasia (PanIN) lesions and the lymphatic network. In mouse models of PanIN (elastase-CreER;LSL-KrasG12D and elastase-CreER;LSL-KrasG12D;p53+/−), the 3-D image data reveal the peri-lesional lymphangiogenesis, endothelial invagination, formation of the bridge/valve-like luminal tubules, vasodilation, and luminal invasion. In the orthotopic mouse model of pancreatic cancer, we identify the localized, graft-induced lymphangiogenesis and the peri- and intra-tumoral lymphatic vessel invasion. Interpretation The integrated view of duct lesions and vascular remodeling suggests an active role, rather than a passive target, of lymphatic vessels in the metastasis of pancreatic cancer. Our 3-D image data provide insights into the pancreatic cancer microenvironment and establish the technical and morphological foundation for systematic detection and 3-D analysis of lymphatic vessel invasion. Fund Taiwan Academia Sinica (AS-107-TP-L15 and AS-105-TP-B15), Ministry of Science and Technology (MOST 106-2321-B-001-048, 106-0210-01-15-02, 106-2321-B-002-034, and 106-2314-B-007-004-MY2), and Taiwan National Health Research Institutes (NHRI EX107-10524EI).
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Affiliation(s)
- Chia-Ning Shen
- Genomics Research Center, Academia Sinica, Taipei, Taiwan; Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - King-Siang Goh
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Chi-Ruei Huang
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Tsai-Chen Chiang
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Yung-Ming Jeng
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Jung Peng
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan; Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Hung-Jen Chien
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Mei-Hsin Chung
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan; Department of Pathology, National Taiwan University Hospital - Hsinchu Branch, Hsinchu, Taiwan
| | - Ya-Hsien Chou
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
| | - Chi-Che Hsieh
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Subhash Kulkarni
- Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Pankaj J Pasricha
- Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yu-Wen Tien
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.
| | - Shiue-Cheng Tang
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan; Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan.
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9
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Abstract
ADP-ribosylation factor-like protein 4A (ARL4A) is a developmentally regulated member of the ARF/ARL GTPase family. The primary structure of ARL4A is very similar to that of other ARF/ARL molecules, but its function remains unclear. The trans-Golgi network golgin GCC185 is required for maintenance of Golgi structure and distinct endosome-to-Golgi transport. We show here that GCC185 acts as a new effector for ARL4 to modulate Golgi organization. ARL4A directly interacts with GCC185 in a GTP-dependent manner. Sub-coiled-coil regions of the CC2 domain of GCC185 are required for the interaction between GCC185 and ARL4A. Depletion of ARL4A reproduces the GCC185-depleted phenotype, causing fragmentation of the Golgi compartment and defects in endosome-to-Golgi transport. GCC185 and ARL4A localize to the Golgi independently of each other. Deletion of the ARL4A-interacting region of GCC185 results in inability to maintain Golgi structure. Depletion of ARL4A impairs the interaction between GCC185 and cytoplasmic linker-associated proteins 1 and 2 (CLASP1 and CLASP2, hereafter CLASPs) in vivo, and abolishes the GCC185-mediated Golgi recruitment of these CLASPs, which is crucial for the maintenance of Golgi structure. In summary, we suggest that ARL4A alters the integrity of the Golgi structure by facilitating the interaction of GCC185 with CLASPs.
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Affiliation(s)
- Yu-Chun Lin
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
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10
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Patel M, Chiang TC, Tran V, Lee FJS, Côté JF. The Arf family GTPase Arl4A complexes with ELMO proteins to promote actin cytoskeleton remodeling and reveals a versatile Ras-binding domain in the ELMO proteins family. J Biol Chem 2011; 286:38969-79. [PMID: 21930703 DOI: 10.1074/jbc.m111.274191] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The prototypical DOCK protein, DOCK180, is an evolutionarily conserved Rac regulator and is indispensable during processes such as cell migration and myoblast fusion. The biological activity of DOCK180 is tightly linked to its binding partner ELMO. We previously reported that autoinhibited ELMO proteins regulate signaling from this pathway. One mechanism to activate the ELMO-DOCK180 complex appears to be the recruitment of this complex to the membrane via the Ras-binding domain (RBD) of ELMO. In the present study, we aimed to identify novel ELMO-interacting proteins to further define the molecular events capable of controlling ELMO recruitment to the membrane. To do so, we performed two independent interaction screens: one specifically interrogated an active GTPase library while the other probed a brain cDNA library. Both methods converged on Arl4A, an Arf-related GTPase, as a specific ELMO interactor. Biochemically, Arl4A is constitutively GTP-loaded, and our binding assays confirm that both wild-type and constitutively active forms of the GTPase associate with ELMO. Mechanistically, we report that Arl4A binds the ELMO RBD and acts as a membrane localization signal for ELMO. In addition, we report that membrane targeting of ELMO via Arl4A promotes cytoskeletal reorganization including membrane ruffling and stress fiber disassembly via an ELMO-DOCK1800-Rac signaling pathway. We conclude that ELMO is capable of interacting with GTPases from Rho and Arf families, leading to the conclusion that ELMO contains a versatile RBD. Furthermore, via binding of an Arf family GTPase, the ELMO-DOCK180 is uniquely positioned at the membrane to activate Rac signaling and remodel the actin cytoskeleton.
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Affiliation(s)
- Manishha Patel
- Institut de Recherches Cliniques de Montréal, Québec H2W 1R7, Canada
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11
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Liu Y, Miller T, Chiang TC. Electronic structure and trilayer growth of indium films on Si(111): a photoemission study. J Phys Condens Matter 2011; 23:365302. [PMID: 21865634 DOI: 10.1088/0953-8984/23/36/365302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report on the preferred trilayer growth of indium films on Si(111) studied by angle-resolved photoemission spectroscopy. By employing an interfactant and optimized annealing conditions, the kinetic constraint on the In atoms due to the substrate is greatly reduced and 'electronic growth'-where film morphology is controlled by the quantized electronic structure of the film-can be achieved at low coverage. Our photoemission spectra reveal that films of 4 ML (monolayers) and 7 ML thicknesses are energetically favored due to a lower surface energy, as confirmed by theoretical calculations. A detailed comparison of the photoemission spectra between In films grown on the In-√3 × √3/Si(111) surface and those on the Si(111) 7 × 7 surface shows that the √3 × √3 interfactant is a better template for growing In films at low coverage and effectively reduces the electronic coupling between the film and the substrate. In addition, the observed band structures of In films are in reasonable agreement with first-principles calculations and suggest that In films grown on the √3 × √3 interfactant might already be close to the bulk-like body-centered tetragonal structure at around 10 ML.
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Affiliation(s)
- Y Liu
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801-3080, USA
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12
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Abstract
ARL4D is a developmentally regulated member of the ADP-ribosylation factor/ARF-like protein (ARF/ARL) family of Ras-related GTPases. Although the primary structure of ARL4D is very similar to that of other ARF/ARL molecules, its function remains unclear. Cytohesin-2/ARF nucleotide-binding-site opener (ARNO) is a guanine nucleotide-exchange factor (GEF) for ARF, and, at the plasma membrane, it can activate ARF6 to regulate actin reorganization and membrane ruffling. We show here that ARL4D interacts with the C-terminal pleckstrin homology (PH) and polybasic c domains of cytohesin-2/ARNO in a GTP-dependent manner. Localization of ARL4D at the plasma membrane is GTP- and N-terminal myristoylation-dependent. ARL4D(Q80L), a putative active form of ARL4D, induced accumulation of cytohesin-2/ARNO at the plasma membrane. Consistent with a known action of cytohesin-2/ARNO, ARL4D(Q80L) increased GTP-bound ARF6 and induced disassembly of actin stress fibers. Expression of inactive cytohesin-2/ARNO(E156K) or small interfering RNA knockdown of cytohesin-2/ARNO blocked ARL4D-mediated disassembly of actin stress fibers. Similar to the results with cytohesin-2/ARNO or ARF6, reduction of ARL4D suppressed cell migration activity. Furthermore, ARL4D-induced translocation of cytohesin-2/ARNO did not require phosphoinositide 3-kinase activation. Together, these data demonstrate that ARL4D acts as a novel upstream regulator of cytohesin-2/ARNO to promote ARF6 activation and modulate actin remodeling.
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Affiliation(s)
- Chun-Chun Li
- *Institute of Molecular Medicine, College of Medicine, National Taiwan University, and Department of Medical Research, National Taiwan University Hospital, Taipei 100, Taiwan; and
| | - Tsai-Chen Chiang
- *Institute of Molecular Medicine, College of Medicine, National Taiwan University, and Department of Medical Research, National Taiwan University Hospital, Taipei 100, Taiwan; and
| | - Tsung-Sheng Wu
- *Institute of Molecular Medicine, College of Medicine, National Taiwan University, and Department of Medical Research, National Taiwan University Hospital, Taipei 100, Taiwan; and
| | - Gustavo Pacheco-Rodriguez
- Pulmonary-Critical Care Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-1434
| | - Joel Moss
- Pulmonary-Critical Care Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-1434
| | - Fang-Jen S. Lee
- *Institute of Molecular Medicine, College of Medicine, National Taiwan University, and Department of Medical Research, National Taiwan University Hospital, Taipei 100, Taiwan; and
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13
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Upton MH, Wei CM, Chou MY, Miller T, Chiang TC. Thermal stability and electronic structure of atomically uniform Pb films on Si(111). Phys Rev Lett 2004; 93:026802. [PMID: 15323937 DOI: 10.1103/physrevlett.93.026802] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2003] [Indexed: 05/24/2023]
Abstract
Atomically uniform Pb films are successfully prepared on Si(111), despite a large lattice mismatch. Angle-resolved photoemission measurements of the electronic structure show layer-resolved quantum well states which can be correlated with dramatic variations in thermal stability. The odd film thicknesses N = 5, 7, and 9 monolayers show sharp quantum well states. The even film thicknesses N = 6 and 8 do not, but are much more stable than the odd film thicknesses. This correlation is discussed in terms of a total energy calculation and Friedel-like oscillations in properties.
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Affiliation(s)
- M H Upton
- Frederick Seitz Materials Research Laboratory, Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801-2902, USA
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14
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Abstract
Chlorine termination of mixed Ge/Si(100) surfaces substantially enhances the contrast between Ge and Si sites in scanning tunneling microscopy observations. This finding enables a detailed investigation of the spatial distribution of Ge atoms deposited on Si(100) by atomic layer epitaxy. The results are corroborated by photoemission measurements aided by an unusually large chemical shift between Cl adsorbed on Si and Ge. Adsorbate-substrate atomic exchange during growth is shown to be important. The resulting interface is thus graded, but characterized by a very short length scale of about one monolayer.
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Affiliation(s)
- D S Lin
- Institute of Physics, National Chiao-Tung University, 1001 Ta-Hsueh Road, Hsinchu 300, Taiwan, Republic of China
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15
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Abstract
We have studied the structural stability of thin silver films with thicknesses of N = 1 to 15 monolayers, deposited on an Fe(100) substrate. Photoemission spectroscopy results show that films of N = 1, 2, and 5 monolayer thicknesses are structurally stable for temperatures above 800 kelvin, whereas films of other thicknesses are unstable and bifurcate into a film with N +/- 1 monolayer thicknesses at temperatures around 400 kelvin. The results are in agreement with theoretical predictions that consider the electronic energy of the quantum well associated with a particular film thickness as a significant contribution to the film stability.
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Affiliation(s)
- D A Luh
- Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, IL 61801-3080, USA
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16
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Abstract
The charge-density-wave transition in TiSe (2), which results in a commensurate (2x2x2) superlattice at temperatures below approximately 200 K, presumably involves softening of a zone-boundary phonon mode. For the first time, this phonon-softening behavior has been examined over a wide temperature range by synchrotron x-ray thermal diffuse scattering.
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Affiliation(s)
- M Holt
- Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080, USA
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17
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Abstract
Gene imprinting is an epigenetic mechanism for accomplishing persistent change in gene expression. In this brief paper, we explore the mechanisms for imprinting genes and present data showing that the synthetic estrogen, diethylstilbestrol (DES) can developmentally imprint genes by changing the pattern of DNA methylation. We further discuss the implications of this and other findings for non-mutagenic aspects of developmental toxicology, and suggest ways to use this concept in modifying in vitro screening for developmental toxicants.
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Affiliation(s)
- J A McLachlan
- Environmental Endocrinology Laboratory, Center for Bioenvironmental Research, Tulane and Xavier Universities, 1340 Tulane Avenue, New Orleans, LA 70112, USA.
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18
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Li S, Chiang TC, Davis GR, Williams RM, Wilson VP, McLachlan JA. Decreased expression of Wnt7a mRNA is inversely associated with the expression of estrogen receptor-alpha in human uterine leiomyoma. J Clin Endocrinol Metab 2001; 86:454-7. [PMID: 11232041 DOI: 10.1210/jcem.86.1.7276] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Wnt-7a gene not only guides the development of the anterior-posterior axis in the female reproductive tract, but also plays a critical role in uterine smooth muscle pattering and maintenance of adult uterine function. This gene is also responsive to changes in the levels of sex steroid hormone in the female reproductive tract. To explore the molecular mechanisms underlying the pathogenesis of uterine leiomyoma, the expression of Wnt7a mRNA in the leiomyoma has been assessed. RT-PCR was performed on uterine leiomyomas and the adjacent myometria. Of 30 cases of leiomyomas studied, 67% showed a decreased mRNA level as compared to the paired myometria. On the other hand, estrogen receptor-alpha (ER-alpha) mRNA is hyper-expressed in 67% of the leiomyomas as compared to their paired myometrium. An inverse association at mRNA expression was found between Wnt7a and ER-alpha. Miller et alhas shown that fetal exposure of DES results in de-regulation of Wnt7a during uterine morphogenesis. Referring to their results, we have postulated that hypersensitivity of leiomyoma cells to estrogen may deregulate the Wnt7a expression. Decreased expression of Wnt7a may lead to loss of control in patterning of the myometrium and result in development of leiomyoma
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Affiliation(s)
- S Li
- Center for Bioenvironmental Research and Department of Pharmacology, Tulane/Xavier Universities, New Orleans, Louisiana 70112-2699, USA.
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19
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Burow ME, Weldon CB, Chiang TC, Tang Y, Collins-Burow BM, Rolfe K, Li S, McLachlan JA, Beckman BS. Differences in protein kinase C and estrogen receptor alpha, beta expression and signaling correlate with apoptotic sensitivity of MCF-7 breast cancer cell variants. Int J Oncol 2000; 16:1179-87. [PMID: 10811993 DOI: 10.3892/ijo.16.6.1179] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Widespread use of MCF-7 human breast cancer cells as a model system for breast cancer has lead to variations in these cells between different laboratories. Although several reports have addressed these differences in terms of proliferation and estrogenic response, differences in sensitivity to apoptosis have just begun to be described. Based on the possible differences in apoptotic sensitivity that may arise due to the existence of MCF-7 cell variants, we determined the relative sensitivity of MCF-7 cell variants from three established laboratories (designated M, L and N) to known inducers of apoptosis. Consistent with our previous studies we demonstrate that differences exist among these variants in regards to tumor necrosis factor alpha (TNF)-induced cell death and inhibition of proliferation in a dose-dependent manner. To establish if the difference in apoptotic susceptibility was specific to TNF, the three MCF-7 cell variants were tested for their response to other known inducers of apoptosis: okadaic acid, staurosporine and 4-hydroxy-tamoxifen. Viability and DNA fragmentation analysis revealed a similar pattern of resistance to apoptosis by all agents in the MCF-7 M variant. The MCF-7 L variant was resistant to okadaic acid and 4-hydroxy-tamoxifen but not staurosporine. In contrast, MCF-7 N cells were sensitive to induction of apoptosis by all agents. The role of both protein kinase C (PKC) and estrogen signaling in the regulation of cell survival prompted investigation of these pathways as a mechanism for differential sensitivity of MCF-7 cell variants to apoptosis. While both estrogen receptor alpha (ERalpha) and ERbeta were expressed in MCF-7 M and N cells, the absence of ERbeta in MCF-7 L cells correlated with decreased estrogen responsiveness of the L variant. Variations in estrogenic responsiveness and PKC isoform expression may account for the enhanced susceptibility of both the L and N variants to staurosporine.
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Affiliation(s)
- M E Burow
- Molecular and Cellular Biology Program, Tulane University School of Medicine, New Orleans, LA, USA
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20
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Chiang TC, Kok VK, Tu HH, Su YM, Yeh CH, Chung MT. Surgical treatment of bronchiectasis: 10 years' experience. Zhonghua Yi Xue Za Zhi (Taipei) 1999; 62:690-4. [PMID: 10533298] [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
BACKGROUND Since antibiotic therapy and vaccination have been widely used in medical practice, the incidence of bronchiectasis has decreased steadily. The principal role of surgery associated with this disease is for the treatment of complications. We present an analysis of surgical results during a 10-year period. METHODS The medical records of bronchiectasis patients who were surgically treated were retrospectively reviewed from July, 1987, to March, 1998. The surgical indications, complications and recurrences of bronchiectasis were evaluated. RESULTS A total of 41 bronchiectasis patients underwent surgical treatment from 1987 to 1998 at our hospital. There were 18 males (mean age, 37.8 +/- 15.3 years; range, 16-73 years), and 23 females (mean age, 33 +/- 7.1 years; range, 21-46 years). The indications for surgery were hemoptysis in 30, failed medical treatment in eight, suspected neoplasm in two and retention of a foreign body in one patient. Anatomic resections of the diseased sites were carried out more frequently on the left lower lobes of the lungs. In total, there were 20 left lower lobes, five right lower lobes, 10 left lingular lobes, five right middle lobes, four left upper lobes and one right upper lobe that required surgery. Surgical complications included hemorrhage in one patient, bronchopleural fistula in one and galactorrhea in one patient. The follow-up intervals were from two to 131 months (mean, 72.5 +/- 37.6 months; median, 74 months). There were two cases of recurrent symptoms and six cases of recurrent hemoptysis; all were easily controlled by medication. There were no mortalities. CONCLUSIONS Surgical treatment of bronchiectasis yields immediate resolution of symptoms, better quality of life and no mortalities. Cessation of smoking, avoiding air pollution and careful medical follow-up are mandatory.
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Affiliation(s)
- T C Chiang
- Department of Surgery, Cardinal Tien Hospital, Hsientien, Taipei, Taiwan, ROC
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21
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Chiang TC, Wang CY. Dead-on-arrival patients in Panchiao, Taipei. Zhonghua Yi Xue Za Zhi (Taipei) 1999; 62:509-13. [PMID: 10462827] [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
BACKGROUND The present emergency medical service (EMS) system in the Panchiao area includes operations in Panchiao, Sulin, Sunshia, Chung Ho and Touchen, which is in the early developmental stage. Educational programs such as emergency medical technician (EMT)-I, and -II have been provided for less than 25% of firefighters in that area. Several mass educational programs in cardiopulmonary resuscitation (CPR) were also provided for the inhabitants of the area. The purpose of this study was to establish a database of dead-on-arrival (DOA) patients during this early stage of the EMS system development so that comparisons of EMS performance could be assessed to identify any future needs of the EMS system in the Panchiao area. METHODS A patient was verified as DOA if there was no pulse nor a response to stimulation. For every DOA patient, several parameters were recorded in a registration book, which began January 1, 1995, and included the following: name, gender, age, mode of transportation, time to hospitalization, on-scene CPR, prehospital basic life support, possible etiology, response to advanced cardiac life support (ACLS), disposition and outcome. The registration book was reviewed and a follow-up study was designed, which covered the entire year of 1995. RESULTS There were 292 DOA patients brought to the emergency room of the Far Eastern Memorial Hospital in Panchiao, Taipei, between January 1, 1995, and December 31, 1995. The study population comprised 190 (65.1%) men and 102 (34.9%) women. The mean age of the men was 51.8 +/- 22.3 years (mean +/- standard deviation). The mean age of the women was 59.8 +/- 24.4 years. Emergency service ambulances transported most DOA patients, though a few were transported by private ambulance from nursing homes. There were only two incidents in which prehospital CPR was conducted. The time to hospitalization varied from five to 170 minutes and averaged 38.3 minutes. Following ACLS, 244 (83.6%) patients were pronounced dead in the emergency room. Cardiovascular and respiratory problems were the leading etiologies and trauma was the second. There were 48 patients (16.4%) who responded to ACLS, but only eight (2.7%) survived until hospital discharge. CONCLUSIONS Delayed initiation of the EMS system resulted in an average time to hospitalization of 38.3 minutes. Cardiovascular collapse was the leading etiology in DOA patients. There were only two patients who received prehospital CPR, suggesting that layperson CPR and EMT education cannot be overemphasized.
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Affiliation(s)
- T C Chiang
- Department of Emergency Medicine, Cardinal Tein Hospital, Hsientien, Taiwan, ROC
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22
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Liang KC, Tsui KY, Tyan YM, Chiang TC. Buspirone impaired acquisition and retention in avoidance tasks: involvement of the hippocampus. CHINESE J PHYSIOL 1998; 41:33-44. [PMID: 9629480] [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: 02/07/2023] Open
Abstract
This study investigated the effects of buspirone on acquisition as well as formation and expression of memory in three different types of avoidance tasks. Rats were trained and tested on a one-trial inhibitory avoidance task, an 8-trial active avoidance task or the Morris water maze. Buspirone (5.0 mg/kg) was administered subcutaneously 30 min before training, immediately after training or 30 min before testing. Retention was tested at various times after training. In the inhibitory avoidance task, pretraining injections of buspirone produced a marked impairing effect on retention, posttraining injections of buspirone produced a moderate but time-dependent memory deficit. Pretest injections of buspirone suppressed retention performance. Such an effect was more pronounced in the 1-day test than in the 21-day test. Intra-hippocampal infusion of buspirone (5.0 micrograms) before testing suppressed expression of the 1-day, but not the 21-day, memory. In the active avoidance task and the Morris water maze, an injection of buspirone before training or testing also impaired acquisition or suppressed retention performance. These findings suggest that buspirone given at various times could compromise acquisition, consolidation and retrieval of affective memory and the hippocampus was involved in the retrieval effect.
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Affiliation(s)
- K C Liang
- Department of Psychology, National Taiwan University, Taipei, ROC
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23
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Affiliation(s)
- I Hertz-Picciotto
- Department of Epidemiology, CB 7400, University of North Carolina, Chapel Hill 27599, USA
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24
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Abstract
OBJECTIVES Roller-type scanners can be used to digitize radiographs. This study evaluated the physical performance of a roller-type scanner with regard to dynamic range, scan reproducibility, and homogeneity. METHODS A VXR-12 (Vidar System Corp., Herndon, Va.) roller-type scanner with imaging editing software Paint Shop Pro (JASC Inc., Minnetonka, Minn.) was used to digitize a step tablet image on Kodak T-MAT G films (Kodak, Rochester, N.Y.). The step tablet image was scanned at various locations and with different scanning settings. The pixel values of the resulting image were analyzed. The step tablet image was also scanned by a Wellhofer WD 102 Filmdensitometer (Wellhofer Dosimetrie, Schwarzenbruck, Germany) to measure the optical densities of the steps on the film for comparison. RESULTS With the use of the default scanning settings the digitized images had pixel values distributed in a similar dynamic range to that of the film densitometer. This scanner produced consistent images with different scanning positions, different orientation of the images, and different power states of the scanner. CONCLUSIONS This roller-type scanner has a similar dynamic range to that of the film densitometer. The operating condition of the scanner is stable, and the resulting image is not significantly affected by the scanning positions. This type of scanner should be suitable for digitizing dental x-ray films, although the limiting scanning resolution might not be sufficient for some diagnostic purposes.
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Affiliation(s)
- S K Chen
- Division of Oral and Maxillofacial Imaging, School of Dentistry, College of Medicine, National Taiwan University, Taipei
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25
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Wang TC, Wu CM, Sun LS, Chiang TC. [Giant cystic hygroma: a case report]. Zhonghua Yi Xue Za Zhi (Taipei) 1993; 51:479-481. [PMID: 8281498] [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: 05/22/2023]
Abstract
Cystic hygromas are congenital malformations of the lymphatic system appearing as single or multiloculated, fluid-filled cavities found mainly in the neck and axilla region. Antenatal ultrasound examination done in this case showed a suspicious giant cystic mass over the neck and chest area. At birth, the mass turned out to be a rare giant cystic hygroma measuring about 25cm x 26cm covering neck, anterior chest, axilla, proximal right upper limb, upper abdomen and upper back area. Because of some compromise to the infant's breathing, an emergency resection was done, and the infant tolerated the procedure well. Pathology report confirmed the diagnosis.
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Affiliation(s)
- T C Wang
- Department of Pediatreics, Far Eastern Memorial Hospital
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26
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Chiang TC, Kok VK, Wong YK. Boerhaave's syndrome--successful treatment of a late case. Zhonghua Yi Xue Za Zhi (Taipei) 1991; 47:50-3. [PMID: 1848463] [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: 12/29/2022]
Abstract
A case of spontaneous rupture of the esophagus (Boerhaave's Syndrome) underwent medical treatment as acute myocardial infarction as initial impression, delay diagnosed 16 days after acute event, and subsequently treated successfully, is presented. Because the patient was critically ill, a conservative management was approached, i.e., NG tube decompression, tube thoracostomy, gastrostomy, broad spectrum antibiotics, TPN to jejunostomy enteral feeding. The patient was salvaged successfully and recovered without complication. The initial unawareness of mediastinal emphysema on chest film resulted in delayed diagnosis.
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Affiliation(s)
- T C Chiang
- Department of Surgery, Far Eastern Memorial Hospital, Taipei, R.O.C
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27
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Liao W, Smith WD, Chiang TC, Williams LR. Rapid, low-cost cleanup procedure for determination of semivolatile organic compounds in human and bovine adipose tissues. J Assoc Off Anal Chem 1988; 71:742-7. [PMID: 3417593] [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: 01/05/2023]
Abstract
A gas chromatographic/mass spectrometric (GC/MS) method is described for determination of organic environmental pollutants in human and bovine adipose tissues. Compounds such as organochlorine pesticides, polychlorinated biphenyls, polynuclear aromatic hydrocarbons, polychlorinated aromatics, and brominated aromatics are extracted with organic solvents and separated from coextracted lipids on a Florisil column. The eluate is concentrated and compounds are identified and quantitated by GC/MS analysis. The method was evaluated in a single laboratory for ability to recover compounds of environmental and regulatory importance. Except for a few more polar compounds, such as phthalates and phosphates, recoveries averaged about 85%. The elution system maximized recovery and allowed minimal coelution of lipid materials. Detection limits for most compounds studied were in the range of 5-50 ng/g (ppb).
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Affiliation(s)
- W Liao
- Lockheed Engineering and Management Services Co., Inc., Environmental Programs, Las Vegas, NV 89119
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Sato K, Hotta M, Kageyama J, Chiang TC, Hu HY, Dong MH, Ling N. Synthesis and in vitro bioactivity of human growth hormone-releasing factor analogs substituted with a single D-amino acid. Biochem Biophys Res Commun 1987; 149:531-7. [PMID: 3122736 DOI: 10.1016/0006-291x(87)90400-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Fifty-four analogs of human growth hormone-releasing factor (hGRF) substituted with a single D-amino acid were synthesized by solid phase methodology. Their capacity to release growth hormone was tested on rat anterior pituitary cells in monolayer culture. Among the series of 28 analogs, which had the amino acid at each position of hGRF (1-29)NH2, except glycine at position 15, substituted by the corresponding D-isomer, [D-Ala2]-, [D-Asp3]-, [D-Asn8]-, [D-Tyr10]-, [D-Asp25]-, [D-Met27]-, [D-Ser28]-, and [D-Arg29]hGRF(1-29)NH2 were as potent as hGRF(1-29)NH2, while [D-Ile5]-, [D-Phe6]-, [D-Thr7]-, and [D-Val13]hGRF(1-29)NH2 showed quite low potencies. Effects of substitution with other D-amino acids in positions 2,3,8,9,10 and 11 were also studied. In most cases, the resulting analogs showed decreased potency, but still retained high intrinsic activity. Only [D-Arg2]hGRF(1-29)NH2 showed very low intrinsic activity and some antagonistic property.
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Affiliation(s)
- K Sato
- Laboratories for Neuroendocrinology, Salk Institute, La Jolla, CA 92037
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29
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Chiang TC, Liao W, Williams LR. Use of solid phase Florisil cartridges to separate fat from semivolatile organic compounds in adipose tissue. J Assoc Off Anal Chem 1987; 70:100-2. [PMID: 3031005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A quick method for separation of semivolatile organic compounds from fat in adipose tissue has been developed. This method uses commercially available solid phase cartridges for sample cleanup. The results indicate that the recoveries, from hexane-extracted fat, of 4 representative classes of organic compounds range from 86.2 to 116%. The solid phase cartridges provide excellent separations of the fat from the analytes; no extraneous interference peaks were detected in the gas chromatograms. The method requires only 0.1 g sample and is quick and simple to use. Although results are reported for samples containing 1-14 ppm, the final extract can be concentrated to a volume allowing detection between 10 and 100 ppb.
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30
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Chan YS, Chiang TC, Cheng YY, Tai KF, Chang HM. [Choleretic effects of acetophenone derivatives and analogues on rats]. Zhongguo Yao Li Xue Bao 1986; 7:443-7. [PMID: 2954420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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31
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Ling N, Baird A, Wehrenberg WB, Ueno N, Munegumi T, Chiang TC, Regno M, Brazeau P. Synthesis and in vitro bioactivity of human growth hormone-releasing factor analogs substituted at position-1. Biochem Biophys Res Commun 1984; 122:304-10. [PMID: 6430292 DOI: 10.1016/0006-291x(84)90475-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Eight position-1 analogs of the 40-amino acid fragment and two position-1 analogs of human growth hormone-releasing factor were synthesized by solid phase methodology and their capacity to release growth hormone was determined using rat anterior pituitary cells in monolayer culture. Relative to hGRF(1-40)OH, which was arbitrarily assigned a potency value of 1, [D-Tyr1]hGRF(1-40)OH, [Phe1]hGRF(1-40)OH, [Trp1]hGRF(1-40)OH, [His1]hGRF(1-40)OH, [Ala1]hGRF(1-40)OH, [(-Ac)Tyr1]hGRF(1-40)OH, Arg0-hGRF(1-40)OH and Ala0-hGRF(1-40)OH have potencies of 0.022, 0.038, 0.003, 0.351, 0.010, 0.032, 0.002 and 0.007 respectively. Relative to hGRF(1-44)NH2 = 1, [(3-Me)His1]hGRF(1-44)NH2 and [(O-Me)Tyr1]hGRF(1-44)NH2 have potencies of 0.132 and 0.001 respectively. These results demonstrate the prerequisite for an aromatic residue at position-1 for potent biological activity and also suggest that the capacity for hydrogen bond formation with the first residue is required for full receptor-ligand interaction.
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32
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Chiang TC, Chang HM, Mak TC. New Oleanene-type Triterpenes from Abrus precatorius and X-ray Crystal Structure of Abrusgenic Acid-Methanol 1:1 Solvate. Planta Med 1983; 49:165-9. [PMID: 17405042 DOI: 10.1055/s-2007-969840] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
From ABRUS PRECATORIUS Abl. triterpenoids abruslactone, methyl abrusgenate and abrusgenic acid were isolated and elucidated by spectroscopic and X-ray techniques.
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Affiliation(s)
- T C Chiang
- Department of Chemistry and Chinese Medicinal Materials Research Centre, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong
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33
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Affiliation(s)
- M P Wong
- Department of Chemistry and Chinese Medicinal Materials Research Centre, The Chinese University of Hong Kong
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34
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Affiliation(s)
- S M Wong
- Department of Chemistry and Chinese Medicinal Materials Research Centre The Chinese University of Hong Kong
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35
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Abstract
After hydrolysis of the saponin fraction of the roots of Abrus cantoniensis, a new triterpenoid sapogenol, cantoniensistriol, was isolated together with sophoradiol, soyasapogenol B and soyasapogenol A. The structures of cantoniensistriol and sophoradiol were elucidated by spectroscopic methods. On the basis of the relation between cantoniensistriol and soyasapogenol A, the steric assignment of the C-21 and C-22 hydroxyl groups of the latter was discussed.
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Affiliation(s)
- T C Chiang
- Chinese Medicinal Material Research Centre, The Chinese University of Hong Kong
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36
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Abstract
A rapid and sensitive method of analysis for retinoic acid in human blood has been developed using gas chromatography-mass spectrometry for separation and detection. The retinoic acid is isolated by solvent extraction into petroleum ether, and converted to methyl retinoate by reacting with dimethylformamide dimethylacetal. The method has been applied to the study of retinoic acid in human blood after subtotal inunction, total inunction and intravenous injection of retinoic acid. The sensitivity limit of 1 ng/ml blood is realized with a 10-ml blood sample.
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37
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Ho BL, Chiang TC. [A study for treadmill exercise protocols for Chinese males (author's transl)]. Taiwan Yi Xue Hui Za Zhi 1980; 79:491-9. [PMID: 6934254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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38
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Chiang TC, Culbert H, Wyman B, Cohen L, Ovadia J. The half field technique of radiation therapy for the cancers of head and neck. Int J Radiat Oncol Biol Phys 1979; 5:1899-901. [PMID: 528255 DOI: 10.1016/0360-3016(79)90580-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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39
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Ho BL, Wang DJ, Lee YT, Chiang TC, Wang SP, Liu CM. [A study of differences in interpretation of exercise electrocardiogram (author's transl)]. Taiwan Yi Xue Hui Za Zhi 1978; 77:859-67. [PMID: 284095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Abstract
The site of origin, the histology, the morphology, the extent, and the T category of the primary carcinoma of nasopharynx and their correlations, including incidence of cervical lymph node metastasis, of 159 consecutive cases seen in a period of four years are studied.
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41
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Sharett T, Fine L, Chiang TC. Rapid afterloading with guide fixation of radioactive sources in cancer of the oral cavity. Am J Roentgenol Radium Ther Nucl Med 1974; 120:182-7. [PMID: 4810296 DOI: 10.2214/ajr.120.1.182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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42
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Lin TM, Chen KP, Lin CC, Hsu MM, Tu SM, Chiang TC, Jung PF, Hirayama T. Retrospective study on nasopharyngeal carcinoma. J Natl Cancer Inst 1973; 51:1403-8. [PMID: 4762926 DOI: 10.1093/jnci/51.5.1403] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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Sarkar B, Bersohn M, Wigfield Y, Chiang TC. Visible, optical rotatory dispersion, and paramagnetic resonance spectra of the L-histidine--cu(II)--L-threonine complex. Can J Biochem 1968; 46:595-600. [PMID: 4298272 DOI: 10.1139/o68-091] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The stability constant of L-histidine-Cu(II)-L-threonine relative to Cu(II)-L-histidine and Cu(II)-L-threonine has been determined. The absorption maxima of Cu(II)-L-histidine and Cu(II)-L-threonine were shown to be at 645 mμ and 625 mμ respectively and a solution containing a mixture of L-histidine, Cu(II), and L-threonine in a 1:1:1 molar ratio shows an absorption maximum at 615 mμ. Shifts in absorption spectra and changes in the optical density were observed when the relative concentration of the ligands in the mixture was changed. The optical rotatory dispersion studies reveal that, in the region 640–700 mμ, it is especially apparent that the molar rotation of the mixed solution is by no means an average of the molar rotation of the Cu(II)-L-histidine and Cu(II)-L-threonine complexes. The three complexes show a close overall similarity of the electron paramagnetic resonance (EPR) parameters. The EPR spectrum of cupric complexes in the mixed solution resembles both the L-threonine and L-histidine complexes in its main features but it differs in significant detail from each of them. The hyperfine splitting of the mixed complex in solution is evidently greater than that of either the Cu(II)–L-histidine or Cu(II)–L-threonine. A structure for L-histidine–Cu(II)–L-threonine is proposed.
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46
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