1
|
Tsai CH, Shih DH, Tu JH, Wu TW, Tsai MG, Shih MH. Analyzing Monthly Blood Test Data to Forecast 30-Day Hospital Readmissions among Maintenance Hemodialysis Patients. J Clin Med 2024; 13:2283. [PMID: 38673554 PMCID: PMC11051209 DOI: 10.3390/jcm13082283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 03/27/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
Background: The increase in the global population of hemodialysis patients is linked to aging demographics and the prevalence of conditions such as arterial hypertension and diabetes mellitus. While previous research in hemodialysis has mainly focused on mortality predictions, there is a gap in studies targeting short-term hospitalization predictions using detailed, monthly blood test data. Methods: This study employs advanced data preprocessing and machine learning techniques to predict hospitalizations within a 30-day period among hemodialysis patients. Initial steps include employing K-Nearest Neighbor (KNN) imputation to address missing data and using the Synthesized Minority Oversampling Technique (SMOTE) to ensure data balance. The study then applies a Support Vector Machine (SVM) algorithm for the predictive analysis, with an additional enhancement through ensemble learning techniques, in order to improve prediction accuracy. Results: The application of SVM in predicting hospitalizations within a 30-day period among hemodialysis patients resulted in an impressive accuracy rate of 93%. This accuracy rate further improved to 96% upon incorporating ensemble learning methods, demonstrating the efficacy of the chosen machine learning approach in this context. Conclusions: This study highlights the potential of utilizing machine learning to predict hospital readmissions within a 30-day period among hemodialysis patients based on monthly blood test data. It represents a significant leap towards precision medicine and personalized healthcare for this patient group, suggesting a paradigm shift in patient care through the proactive identification of hospitalization risks.
Collapse
Affiliation(s)
- Cheng-Han Tsai
- Department of Information Management and Institute of Healthcare Information Management, National Chung Cheng University, Chiayi City 62102, Taiwan or
- Department of Emergency Medicine, Chiayi Branch, Taichung Veteran’s General Hospital, Chiayi City 60090, Taiwan
| | - Dong-Her Shih
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan;
| | - Jue-Hong Tu
- Department of Nephrology, St. Joseph’s Hospital, Yunlin 63241, Taiwan; (J.-H.T.); (M.-G.T.)
| | - Ting-Wei Wu
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan;
| | - Ming-Guei Tsai
- Department of Nephrology, St. Joseph’s Hospital, Yunlin 63241, Taiwan; (J.-H.T.); (M.-G.T.)
| | - Ming-Hung Shih
- Department of Electrical and Computer Engineering, Iowa State University, 2520 Osborn Drive, Ames, IA 50011, USA;
| |
Collapse
|
2
|
Shih DH, Wu YH, Wu TW, Chang SC, Shih MH. Infodemiology of Influenza-like Illness: Utilizing Google Trends' Big Data for Epidemic Surveillance. J Clin Med 2024; 13:1946. [PMID: 38610711 PMCID: PMC11012909 DOI: 10.3390/jcm13071946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 03/18/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024] Open
Abstract
Background: Influenza-like illness (ILI) encompasses symptoms similar to influenza, affecting population health. Surveillance, including Google Trends (GT), offers insights into epidemic patterns. Methods: This study used multiple regression models to analyze the correlation between ILI incidents, GT keyword searches, and climate variables during influenza outbreaks. It compared the predictive capabilities of time-series and deep learning models against ILI emergency incidents. Results: The GT searches for "fever" and "cough" were significantly associated with ILI cases (p < 0.05). Temperature had a more substantial impact on ILI incidence than humidity. Among the tested models, ARIMA provided the best predictive power. Conclusions: GT and climate data can forecast ILI trends, aiding governmental decision making. Temperature is a crucial predictor, and ARIMA models excel in forecasting ILI incidences.
Collapse
Affiliation(s)
- Dong-Her Shih
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan; (D.-H.S.); (Y.-H.W.); (S.-C.C.)
| | - Yi-Huei Wu
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan; (D.-H.S.); (Y.-H.W.); (S.-C.C.)
| | - Ting-Wei Wu
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan; (D.-H.S.); (Y.-H.W.); (S.-C.C.)
| | - Shu-Chi Chang
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan; (D.-H.S.); (Y.-H.W.); (S.-C.C.)
| | - Ming-Hung Shih
- Department of Electrical and Computer Engineering, Iowa State University, 2520 Osborn Drive, Ames, IA 50011, USA;
| |
Collapse
|
3
|
Chu M, Bao R, Strasser M, Ikehara K, Everest J, Maeda L, Hochmuth K, Xu L, McNichol A, Bellanova P, Rasbury T, Kölling M, Riedinger N, Johnson J, Luo M, März C, Straub S, Jitsuno K, Brunet M, Cai Z, Cattaneo A, Hsiung K, Ishizawa T, Itaki T, Kanamatsu T, Keep M, Kioka A, McHugh C, Micallef A, Pandey D, Proust JN, Satoguchi Y, Sawyer D, Seibert C, Silver M, Virtasalo J, Wang Y, Wu TW, Zellers S. Earthquake-enhanced dissolved carbon cycles in ultra-deep ocean sediments. Nat Commun 2023; 14:5427. [PMID: 37696798 PMCID: PMC10495447 DOI: 10.1038/s41467-023-41116-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 08/23/2023] [Indexed: 09/13/2023] Open
Abstract
Hadal trenches are unique geological and ecological systems located along subduction zones. Earthquake-triggered turbidites act as efficient transport pathways of organic carbon (OC), yet remineralization and transformation of OC in these systems are not comprehensively understood. Here we measure concentrations and stable- and radiocarbon isotope signatures of dissolved organic and inorganic carbon (DOC, DIC) in the subsurface sediment interstitial water along the Japan Trench axis collected during the IODP Expedition 386. We find accumulation and aging of DOC and DIC in the subsurface sediments, which we interpret as enhanced production of labile dissolved carbon owing to earthquake-triggered turbidites, which supports intensive microbial methanogenesis in the trench sediments. The residual dissolved carbon accumulates in deep subsurface sediments and may continue to fuel the deep biosphere. Tectonic events can therefore enhance carbon accumulation and stimulate carbon transformation in plate convergent trench systems, which may accelerate carbon export into the subduction zones.
Collapse
Affiliation(s)
- Mengfan Chu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China
| | - Rui Bao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China.
| | - Michael Strasser
- University of Innsbruck, Institute of Geology, Innsbruck, Austria
| | - Ken Ikehara
- National Institute of Advanced Industrial Science and Technology (AIST), Geological Survey of Japan, Institute of Geology and Geoinformation, Ibaraki, 305-8567, Japan
| | - Jez Everest
- British Geological Survey, Lyell Centre, Edinburgh, EH14 4AP, UK
| | - Lena Maeda
- Center for Deep Earth Exploration, Japan Agency for Marine-Earth Science and Technology, Kanagawa, 236-0001, Japan
| | - Katharina Hochmuth
- School of Geography, Geology and the Environment, University of Leicester, Leicester, UK
- Australian Centre for Excellence in Antarctic Sciences, Institute for Marine and Antarctic Studies, University of Tasmania, 20 Castray Esplanade, Battery Point TAS, Churchill Ave, 7004, Australia
| | - Li Xu
- NOSAMS Laboratory, Woods Hole Oceanographic Institution, Massachusetts, USA
| | - Ann McNichol
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Massachusetts, USA
| | - Piero Bellanova
- RWTH Aachen University, Institute of Neotectonics and Natural Hazards & Institute of Geology and Geochemistry of Petroleum and Coal, 52056, Aachen, Germany
| | - Troy Rasbury
- Stony Brook University, Department of Geosciences, New York, 11794, USA
| | - Martin Kölling
- MARUM - Center for Marine Environmental Science, University of Bremen, Bremen, 28359, Germany
| | - Natascha Riedinger
- Boone Pickens School of Geology, Oklahoma State University, Oklahoma, 74078, USA
| | - Joel Johnson
- University of New Hampshire, Department of Earth Sciences, New Hampshire, 03824, USA
| | - Min Luo
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Christian März
- School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK
- Institute for Geosciences, University of Bonn, Nussallee 8, 53115, Bonn, Germany
| | - Susanne Straub
- Lamont Doherty Earth Observatory, Geochemistry Division, New York, 10964, USA
| | - Kana Jitsuno
- Department of Life Science and Medical Bioscience, Waseda University, Tokyo, 162-0041, Japan
| | - Morgane Brunet
- Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 35000, Rennes, France
| | - Zhirong Cai
- Kyoto University, Department of Geology and Mineralogy, Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto, 606-8502, Japan
| | - Antonio Cattaneo
- Geo-Ocean, UMR 6538, Univ Brest, CNRS, Ifremer, Plouzané, F-29280, France
| | - Kanhsi Hsiung
- Research Institute for Marine Geodynamics, JAMSTEC, Marine Geology and Geophysics Research Group, Subduction Dynamics Research Center, Kanagawa, 237-0061, Japan
| | - Takashi Ishizawa
- International Research Institute of Disaster Science, Tohoku University, Sendai, 980-0845, Japan
| | - Takuya Itaki
- National Institute of Advanced Industrial Science and Technology (AIST), Geological Survey of Japan, Institute of Geology and Geoinformation, Ibaraki, 305-8567, Japan
| | - Toshiya Kanamatsu
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Research Institute of Marine Geodynamics (IMG), Yokosuka, 237-0061, Japan
| | - Myra Keep
- The University of Western Australia, Department School of Earth Sciences, Perth, Australia
| | - Arata Kioka
- Kyushu University, Department of Earth Resources Engineering, Fukuoka, 819-0395, Japan
| | - Cecilia McHugh
- Queens College, City University of New York, School of Earth and Environmental Sciences, New York, 11367, USA
| | - Aaron Micallef
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, D-24148, Germany
| | - Dhananjai Pandey
- National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Government of India, Goa, 403 804, India
| | - Jean Noël Proust
- Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 35000, Rennes, France
| | | | - Derek Sawyer
- The Ohio State University, School of Earth Sciences, Ohio, 43210, USA
| | - Chloé Seibert
- Lamont Doherty Earth Observatory, Marine geology and geophysics division, New York, 10964, USA
| | - Maxwell Silver
- Colorado School of Mines, Hydrologic Science and Engineering, Colorado, 80227, USA
| | | | - Yonghong Wang
- Ocean University of China, Department of Marine Geosciences, Qingdao, 266100, China
| | - Ting-Wei Wu
- MARUM - Center for Marine Environmental Science, University of Bremen, Bremen, 28359, Germany
- Norwegian Geotechnical Institute, Oslo, Norway
| | - Sarah Zellers
- University of Central Missouri, Department of Physical Sciences, Missouri, 64093, USA
| |
Collapse
|
4
|
Lan DY, He PJ, Qi YP, Wu TW, Xian HY, Wang RH, Lü F, Zhang H. Optimizing the Quality of Machine Learning for Identifying the Share of Biogenic and Fossil Carbon in Solid Waste. Anal Chem 2023; 95:4412-4420. [PMID: 36820858 DOI: 10.1021/acs.analchem.2c04940] [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: 02/24/2023]
Abstract
Insights into carbon sources (biogenic and fossil carbon) and contents in solid waste are vital for estimating the carbon emissions from incineration plants. However, the traditional methods are time-, labor-, and cost-intensive. Herein, high-quality data sets were established after analyzing the carbon contents and infrared spectra of substantial samples using elemental analysis and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), respectively. Then, five classification and eight regression machine learning (ML) models were evaluated to recognize the proportion of biogenic and fossil carbon in solid waste. Using the optimized data preprocessing approach, the random forest (RF) classifier with hyperparameter tuning ranked first in classifying the carbon group with a test accuracy of 0.969, and the carbon contents were successfully predicted by the RF regressor with R2 = 0.926 considering performance-interpretability-computation time competition. The above proposed algorithms were further validated with real environmental samples, which exhibited robust performance with an accuracy of 0.898 for carbon group classification and an R2 value of 0.851 for carbon content prediction. The reliable results indicate that ATR-FTIR coupled with ML algorithms is feasible for rapidly identifying both carbon groups and content, facilitating the calculation and assessment of carbon emissions from solid waste incineration.
Collapse
Affiliation(s)
- Dong-Ying Lan
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Pin-Jing He
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.,Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Ya-Ping Qi
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Ting-Wei Wu
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Hao-Yang Xian
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Rui-Heng Wang
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Fan Lü
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.,Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Hua Zhang
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.,Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| |
Collapse
|
5
|
Shih DH, Liao CH, Wu TW, Xu XY, Shih MH. Dysarthria Speech Detection Using Convolutional Neural Networks with Gated Recurrent Unit. Healthcare (Basel) 2022; 10:healthcare10101956. [PMID: 36292403 PMCID: PMC9602047 DOI: 10.3390/healthcare10101956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/02/2022] [Accepted: 10/05/2022] [Indexed: 11/04/2022] Open
Abstract
In recent years, due to the rise in the population and aging, the prevalence of neurological diseases is also increasing year by year. Among these patients with Parkinson’s disease, stroke, cerebral palsy, and other neurological symptoms, dysarthria often appears. If these dysarthria patients are not quickly detected and treated, it is easy to cause difficulties in disease course management. When the symptoms worsen, they can also affect the patient’s psychology and physiology. Most of the past studies on dysarthria detection used machine learning or deep learning models as classification models. This study proposes an integrated CNN-GRU model with convolutional neural networks and gated recurrent units to detect dysarthria. The experimental results show that the CNN-GRU model proposed in this study has the highest accuracy of 98.38%, which is superior to other research models.
Collapse
Affiliation(s)
- Dong-Her Shih
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan
| | - Ching-Hsien Liao
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan
| | - Ting-Wei Wu
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan
- Correspondence:
| | - Xiao-Yin Xu
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan
| | - Ming-Hung Shih
- Department of Electrical and Computer Engineering, Iowa State University, 2520 Osborn Drive, Ames, IA 50011, USA
| |
Collapse
|
6
|
Shih DH, Shih PL, Wu TW, Liang SH, Shih MH. An International Federal Hyperledger Fabric Verification Framework for Digital COVID-19 Vaccine Passport. Healthcare (Basel) 2022; 10:healthcare10101950. [PMID: 36292397 PMCID: PMC9601543 DOI: 10.3390/healthcare10101950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 09/30/2022] [Accepted: 10/03/2022] [Indexed: 11/04/2022] Open
Abstract
The COVID-19 virus has been spreading worldwide on a large scale since 2019, and the most effective way to prevent COVID-19 is to vaccinate. In order to prove that vaccination has been administered to allow access to different areas, paper vaccine passports are produced. However, paper vaccine passport records are vulnerable to counterfeiting or abuse. Previous research has suggested that issuing certificates digitally is an easier way to verify them. This study used the consortium blockchain based on Hyperledger Fabric to upload the digital vaccine passport (DVP) to the blockchain network. In order to enable collaboration across multiple systems, networks, and organizations in different trust realms. Federated Identity Management is considered a promising approach to facilitate secure resource sharing between collaborating partners. Therefore, the international federal identity management architecture proposed in this study enables inspectors in any country to verify the authenticity of the DVP of incoming passengers using the consortium blockchain. Through practical construction, the international federal Hyperledger verification framework for the DVP proposed in this study has shown the feasibility of issuing a global DVP in safety analysis and efficacy testing.
Collapse
Affiliation(s)
- Dong-Her Shih
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan
- Correspondence:
| | - Pai-Ling Shih
- Department of Information Management, National Chung Cheng University, Chiayi 621301, Taiwan
| | - Ting-Wei Wu
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan
| | - Shu-Huai Liang
- Department of Information Management, National Yunlin University of Science and Technology, Douliu 64002, Taiwan
| | - Ming-Hung Shih
- Department of Electrical and Computer Engineering, Iowa State University, 2520 Osborn Drive, Ames, IA 50011, USA
| |
Collapse
|
7
|
Hsu YF, Wu TW, Kang YH, Wu CY, Liu YH, Peng SM, Kong KV, Yang JS. Porous Supramolecular Assembly of Pentiptycene-Containing Gold(I) Complexes: Persistent Excited-State Aurophilicity and Inclusion-Induced Emission Enhancement. Inorg Chem 2022; 61:11981-11991. [PMID: 35838662 DOI: 10.1021/acs.inorgchem.2c01786] [Citation(s) in RCA: 1] [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] [Indexed: 11/28/2022]
Abstract
We report herein a porous supramolecular framework formed by a linear mononuclear Au(I) complex (1) via the tongue-and-groove-like joinery between the pentiptycene U-cavities (grooves) and the rod-shaped π-conjugated backbone and alkyl chains (tongues) with the assistance of C-H···π and aurophilic interactions. The framework contains distorted tetrahedral Au4 units, which undergo stepwise and persistent photoinduced Au(I)-Au(I) bond shortening (excited-state aurophilicity), leading to multicolored luminescence photochromism. The one-dimensional pore channels could accommodate different solvates and guests, and the guest inclusion-induced luminescence enhancement (up to 300%) and/or vapochromism are characterized. A correlation between the aurophilic bonding and the luminescence activity is uncovered by TDDFT calculations. Isostructural derivatives 2 and 3 corroborate both the robustness of the porous supramolecular assembly and the mechanisms of the stimulation-induced luminescence properties of 1. This work demonstrates the cooperation of aurophilicity and structural porosity and adaptability in achieving novel supramolecular photochemical properties.
Collapse
Affiliation(s)
- Ying-Feng Hsu
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| | - Ting-Wei Wu
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| | - Yu-Hsuan Kang
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| | - Cheng-Yun Wu
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| | - Yi-Hung Liu
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| | - Shie-Ming Peng
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| | - Kien Voon Kong
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| | - Jye-Shane Yang
- Department of Chemistry, National Taiwan University, Taipei 10617 Taiwan
| |
Collapse
|
8
|
Lan DY, Zhang H, Wu TW, Lü F, Shao LM, He PJ. Repercussions of clinical waste co-incineration in municipal solid waste incinerator during COVID-19 pandemic. J Hazard Mater 2022; 423:127144. [PMID: 34555763 PMCID: PMC8440058 DOI: 10.1016/j.jhazmat.2021.127144] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 08/24/2021] [Accepted: 09/02/2021] [Indexed: 05/10/2023]
Abstract
During coronavirus disease 2019 pandemic, the exponential increase in clinical waste (CW) generation has caused immense burden to CW treatment facilities. Co-incineration of CW in municipal solid waste incinerator (MSWI) is an emergency treatment method. A material flow model was developed to estimate the change in feedstock characteristics and resulting acid gas emission under different CW co-incineration ratios. The ash contents and lower heating values of the feedstocks, as well as HCl concentrations in flue gas showed an upward trend. Subsequently, 72 incineration residue samples were collected from a MSWI performing co-incineration (CW ratio <10 wt%) in Wuhan city, China, followed by 20 incineration residues samples from waste that were not co-incineration. The results showed that the contents of major elements and non-volatile heavy metals in the air pollution control residues increased during co-incineration but were within the reported ranges, whereas those in the bottom ashes revealed no significant changes. The impact of CW co-incineration at a ratio <10 wt% on the distribution of elements in the incineration residues was not significant. However, increase in alkali metals and HCl in flue gas may cause potential boiler corrosion. These results provide valuable insights into pollution control in MSWI during pandemic.
Collapse
Affiliation(s)
- Dong-Ying Lan
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Hua Zhang
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization, Shanghai 200092, China.
| | - Ting-Wei Wu
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Fan Lü
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization, Shanghai 200092, China
| | - Li-Ming Shao
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization, Shanghai 200092, China
| | - Pin-Jing He
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization, Shanghai 200092, China
| |
Collapse
|
9
|
Shih DH, Wu TW, Liu WX, Shih PY. An Azure ACES Early Warning System for Air Quality Index Deteriorating. Int J Environ Res Public Health 2019; 16:E4679. [PMID: 31771273 PMCID: PMC6926579 DOI: 10.3390/ijerph16234679] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 11/03/2019] [Accepted: 11/21/2019] [Indexed: 11/16/2022]
Abstract
With the development of industrialization and urbanization, air pollution in many countries has become more serious and has affected people's health. The air quality has been continuously concerned by environmental managers and the public. Therefore, accurate air quality deterioration warning system can avoid health hazards. In this study, an air quality index (AQI) warning system based on Azure cloud computing platform is proposed. The prediction model is based on DFR (Decision Forest Regression), NNR (Neural Network Regression), and LR (Linear Regression) machine learning algorithms. The best algorithm was selected to calculate the 6 pollutants required for the AQI calculation of the air quality monitoring in real time. The experimental results show that the LR algorithm has the best performance, and the method of this study has a good prediction on the AQI index warning for the next one to three hours. Based on the ACES system proposed, it is hoped that it can prevent personal health hazards and help to reduce medical costs in public.
Collapse
Affiliation(s)
- Dong-Her Shih
- Department of Information Management, National Yunlin University of Science and Technology, 123, Section 3, University Road, Douliu 640, Taiwan; (T.-W.W.); (W.-X.L.)
| | - Ting-Wei Wu
- Department of Information Management, National Yunlin University of Science and Technology, 123, Section 3, University Road, Douliu 640, Taiwan; (T.-W.W.); (W.-X.L.)
| | - Wen-Xuan Liu
- Department of Information Management, National Yunlin University of Science and Technology, 123, Section 3, University Road, Douliu 640, Taiwan; (T.-W.W.); (W.-X.L.)
| | - Po-Yuan Shih
- Department of Finance, National Yunlin University of Science and Technology, 123, Section 3, University Road, Douliu 640, Taiwan;
| |
Collapse
|
10
|
D'Arezzo Pessente G, Darrieux FD, Sacilotto LS, Olivetti NO, Wulkan FW, Oliveira TO, Hachul DH, Wu TW, Scavacca MS, Krieger JK, Pereira AP. P4797Genetic testing in 101 consecutive lone atrial fibrillation patients is able to identify a subgroup with increased severity. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.1173] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
Atrial fibrillation (AF) is the most common arrhythmia and the cause of 15% of all strokes and up to 6% of medical admissions. It is estimated that currently about 2.0 million Brazilians, and 30 million individuals worldwide, are affected by the disease. It is a complex and multifactorial disease, and the mechanisms are still not well understood. Between 10–20% of AF patients do not have any known predisposing factors, a condition once called “lone AF”. The role of genetic testing still remains controversial in this clinical scenario.
Purpose
The aim of this study was to identify the occurrence of pathogenic genetic variants in patients with atrial fibrillation without known risk factors.
Methods
In a tertiary hospital, 101 young patients with apparent “lone AF” were screened with genetic testing by NGS using a custom genetic panel with 159 channelopathy and cardiomyopathy related genes. Variants found were classified according to the American College of Genetic and Genomic (ACMG) criteria. Subjects were evaluated with clinical and familial history, electrocardiogram, 24 hours Holter monitoring, echocardiogram, cardiac MRI and treatment response. Multivariate analyses were performed by logistic linear regression model.
Results
During an inclusion period of 4 years, 101 consecutive patients, with mean age of 38.6 years old, were classified as “lone AF” (78% male); 76% presented paroxysmal AF and 24% persistent/permanent AF. Family history of early sudden death (bellow 60 years old) was reported in 37% of cases (78% below 50 years old); 10% had family members with pacemakers; and 44% reported having family members with early AF onset. Genetic testing demonstrated that 14/101 (13.8%) of patients presented genetic variants classified as pathogenic or likely pathogenic (P/LP) according to ACMG criteria. The genes most frequently affected were LMNA (3/101), ANK2 (3/101) and truncating variants in TTN (3/101). Two variables were significantly associated with harboring a pathogenic mutation: family history of sudden death (OR: 5.58; 1,19–26,12 CI; p=0.029) and pacemaker reported in the family history (OR: 6.83; 1.11–42.04 CI; p=0.038).
Conclusion
Our data showed that approximately 15% of “lone AF” patients are carriers of known pathogenic mutations in genes associated with inherithed cardiomyopathy. In addition, we show that being a carrier is potentially associated with a more severe phenotype. These findings suggest that genetic testing in “lone AF” patients may be able to identify a subgroup with a more severe phenotype are for whom a different management strategy might be indicated.
Acknowledgement/Funding
National Council for Scientific and Technological Development (CNPq)
Collapse
Affiliation(s)
| | - F D Darrieux
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - L S Sacilotto
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - N O Olivetti
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - F W Wulkan
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - T O Oliveira
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - D H Hachul
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - T W Wu
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - M S Scavacca
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - J K Krieger
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| | - A P Pereira
- Heart Institute of the University of Sao Paulo (InCor), Sao Paulo, Brazil
| |
Collapse
|
11
|
Wu TW, Cui R, Zhang BX. [Determination of 8-methoxypsoralen in mouse plasma by high performance liquid chromatography and its application to pharmacokinetic study]. Beijing Da Xue Xue Bao Yi Xue Ban 2018; 50:792-796. [PMID: 30337737] [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: 06/08/2023]
Abstract
OBJECTIVE To establish a high performance liquid chromatography (HPLC) method for the determination of 8-methoxypsoralen (8-MOP) in mouse plasma and apply it to a pharmacokinetic study of 8-MOP. METHODS 8-MOP was separated on a Waters Symmetry18 column (250 mm × 4.6 mm, 5 μm) and determined by HPLC using isocratic elution, and 5-methoxypsoralen was used as internal standard. The mobile phase consisted of methanol-water (55:45, V/V) at a flow rate of 1.0 mL/min. The excitation and emission wavelength of fluorescence detector were set at 334 nm and 484 nm respectively, and the internal standard method was used for quantitative analysis. In the study, 60 healthy ICR male mice were randomly divided into twelve groups. The mice in control group were administered intragastrically with 1% Tween 80, and the mice in the other eleven groups were administered intragastrically with 8-MOP (40 mg/kg). Plasma concentrations of 8-MOP in the mice at different time points after treatment were determined by HPLC. Pharmacokinetic parameters were calculated by DAS 2.0 software. RESULTS The calibration curve of 8-MOP was linear with a correlation coefficient of 0.999 3 over the concentration range of 0.05 to 10 mg/L, and the limit of detection was 0.015 mg/L. The average recoveries of 8? MOP at three different concentrations (0.10, 0.50, 2.5 mg/L) were from 92.5% to 100.6%. The intra-day precision of 8-MOP was from 3.3% to 8.2%, while the inter-day precision was from 3.4% to 6.7% at three spiked concentration levels. The extraction recoveries of 8-MOP were from 90.9% to 92.0%, and the plasma samples could be stored at -80°C for 15 days at least at three spiked concentration levels. 8-MOP could be detected in mouse plasma 5 min after intragastrical administration to the mice (1.4 mg/L). The concentration of 8-MOP in the mouse plasma reached a maximum 2 h after administration, and 8-MOP could still be detected 24 h after administration (1.1 mg/L). t1/2 was (39.21±3.65) h, Cmax was (2.31±0.02) mg/L, tmax was (2.00±0.00) h, and AUC0-t was (33.34±1.19) (h×mg)/L. CONCLUSION The proposed method is accurate and simple,suitable for pharmacokinetics of 8-MOP in mice.
Collapse
Affiliation(s)
- T W Wu
- Department of Occupational and Environmental Health Sciences,Peking University School of Public Health, Beijing 100191, China
| | - R Cui
- Department of Occupational and Environmental Health Sciences,Peking University School of Public Health, Beijing 100191, China
| | - B X Zhang
- Department of Toxicology, Peking University School of Public Health, Beijing 100191, China
| |
Collapse
|
12
|
Zheng YZ, Wu TW, Yu LK, Wei YC, Liu WC, Soo YL, Chang SL. Simultaneous determination of tensile and shear strains of crystalline bilayers using three Bragg reflections of X-rays. J Appl Crystallogr 2016. [DOI: 10.1107/s1600576716009572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
A method for the simultaneous determination of nine strain coefficients, both shear and tensile, of crystalline bilayers is proposed and realized. The X-ray diffraction peak intensities along 2θ (vertical) and β (horizontal) scans relative to the plane of incidence of three Bragg reflections whose atomic planes are not parallel to each other can be used to obtain shear and tensile strain coefficients. The theoretical considerations and experimental examples for single-crystal GeSi/Si overlayers are reported. It is also demonstrated that, for GeSi/Si, the shear and tensile strain coefficients of the Si substrate tend to vanish when the GeSi layer is thicker than 40 nm.
Collapse
|
13
|
Zeng YS, Gao RC, Wu TW, Cho C, Tan KT. Fluorescent Probe Encapsulated in SNAP-Tag Protein Cavity To Eliminate Nonspecific Fluorescence and Increase Detection Sensitivity. Bioconjug Chem 2016; 27:1872-9. [DOI: 10.1021/acs.bioconjchem.6b00290] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yan-Syun Zeng
- Department of Chemistry, and ‡Frontier Research Center on Fundamental
and Applied
Sciences of Matters, National Tsing Hua University, 101 Sec.
2, Kuang Fu Road, Hsinchu 30013, Taiwan, ROC
| | - Ruo-Cing Gao
- Department of Chemistry, and ‡Frontier Research Center on Fundamental
and Applied
Sciences of Matters, National Tsing Hua University, 101 Sec.
2, Kuang Fu Road, Hsinchu 30013, Taiwan, ROC
| | - Ting-Wei Wu
- Department of Chemistry, and ‡Frontier Research Center on Fundamental
and Applied
Sciences of Matters, National Tsing Hua University, 101 Sec.
2, Kuang Fu Road, Hsinchu 30013, Taiwan, ROC
| | - Chien Cho
- Department of Chemistry, and ‡Frontier Research Center on Fundamental
and Applied
Sciences of Matters, National Tsing Hua University, 101 Sec.
2, Kuang Fu Road, Hsinchu 30013, Taiwan, ROC
| | - Kui-Thong Tan
- Department of Chemistry, and ‡Frontier Research Center on Fundamental
and Applied
Sciences of Matters, National Tsing Hua University, 101 Sec.
2, Kuang Fu Road, Hsinchu 30013, Taiwan, ROC
| |
Collapse
|
14
|
Wu TW, Lee FH, Gao RC, Chew CY, Tan KT. Fluorescent Probe Encapsulated in Avidin Protein to Eliminate Nonspecific Fluorescence and Increase Detection Sensitivity in Blood Serum. Anal Chem 2016; 88:7873-7. [DOI: 10.1021/acs.analchem.6b02111] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Ting-Wei Wu
- Department of Chemistry, National Tsing Hua University, 101 Section
2, Kuang Fu Road, Hsinchu 30013, Taiwan, Republic of China
| | - Fang-Hong Lee
- Department of Chemistry, National Tsing Hua University, 101 Section
2, Kuang Fu Road, Hsinchu 30013, Taiwan, Republic of China
| | - Ruo-Cing Gao
- Department of Chemistry, National Tsing Hua University, 101 Section
2, Kuang Fu Road, Hsinchu 30013, Taiwan, Republic of China
| | - Chee Ying Chew
- Department of Chemistry, National Tsing Hua University, 101 Section
2, Kuang Fu Road, Hsinchu 30013, Taiwan, Republic of China
| | - Kui-Thong Tan
- Department of Chemistry, National Tsing Hua University, 101 Section
2, Kuang Fu Road, Hsinchu 30013, Taiwan, Republic of China
- Frontier Research Center on Fundamental and Applied Sciences
of Matters, National Tsing Hua University, 101 Section 2, Kuang Fu Road, Hsinchu 30013, Taiwan, Republic of China
| |
Collapse
|
15
|
Yu WT, Wu TW, Huang CL, Chen IC, Tan KT. Protein sensing in living cells by molecular rotor-based fluorescence-switchable chemical probes. Chem Sci 2016; 7:301-307. [PMID: 28758005 PMCID: PMC5515057 DOI: 10.1039/c5sc02808f] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [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: 07/31/2015] [Accepted: 09/30/2015] [Indexed: 12/19/2022] Open
Abstract
In this paper, we introduce a general design to construct fluorescence-switching probes by using conjugates of a fluorescent molecular rotor and protein specific ligands for the selective protein detection and real-time tracking of protein degradation in living cells. Upon the interaction of the ligand with the protein ligand-binding domain, the crowded surroundings restrict the bond rotation of the fluorescent molecular rotor to trigger the emission of a strong fluorescence signal, which is reduced upon the addition of a competitive ligand or after protein degradation. With this probe design, two fluorescent probes for MGMT and hCAII proteins were constructed and applied for detecting the endogenous proteins in living cells. In addition, real-time degradation kinetics of the alkylated-MGMT at the single living cell level were revealed for the first time. We believe that this fluorescence-switching probe design can possibly be extended for the analysis of other proteins, for which there are still no effective tools to visualize them in living cells.
Collapse
Affiliation(s)
- Wan-Ting Yu
- Department of Chemistry , National Tsing Hua University , 101 Sec. 2, Kuang Fu Rd , Hsinchu 30013 , Taiwan , Republic of China . ; Tel: +886-3-5715131
| | - Ting-Wei Wu
- Department of Chemistry , National Tsing Hua University , 101 Sec. 2, Kuang Fu Rd , Hsinchu 30013 , Taiwan , Republic of China . ; Tel: +886-3-5715131
| | - Chi-Ling Huang
- Department of Chemistry , National Tsing Hua University , 101 Sec. 2, Kuang Fu Rd , Hsinchu 30013 , Taiwan , Republic of China . ; Tel: +886-3-5715131
| | - I-Chia Chen
- Department of Chemistry , National Tsing Hua University , 101 Sec. 2, Kuang Fu Rd , Hsinchu 30013 , Taiwan , Republic of China . ; Tel: +886-3-5715131
- Frontier Research Center on Fundamental and Applied Sciences of Matters , National Tsing Hua University , 101 Sec. 2, Kuang Fu Rd , Hsinchu 30013 , Taiwan , Republic of China
| | - Kui-Thong Tan
- Department of Chemistry , National Tsing Hua University , 101 Sec. 2, Kuang Fu Rd , Hsinchu 30013 , Taiwan , Republic of China . ; Tel: +886-3-5715131
- Frontier Research Center on Fundamental and Applied Sciences of Matters , National Tsing Hua University , 101 Sec. 2, Kuang Fu Rd , Hsinchu 30013 , Taiwan , Republic of China
| |
Collapse
|
16
|
Wu TW, Lee JW, Liu HY, Lin WH, Chu CY, Lin SL, Chang-Chien GP, Yu C. Accumulation and elimination of polychlorinated dibenzo-p-dioxins and dibenzofurans in mule ducks. Sci Total Environ 2014; 497-498:260-266. [PMID: 25129161 DOI: 10.1016/j.scitotenv.2014.07.106] [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] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 07/26/2014] [Accepted: 07/27/2014] [Indexed: 06/03/2023]
Abstract
In Taiwan, a food safety crisis involving a presence of high concentrations of dioxin residues in duck eggs occurred in 2004. The dioxin content in duck meat sampled from supermarkets was also reported to be substantially higher than in products from other farm animals. Despite increased awareness of the potential for contamination and exposure to dioxins, the accumulation and elimination of dioxins in ducks have not been well characterized. In the present study, mule ducks were fed capsules containing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) for 14 days and the trial was continued for another 28 days without PCDD/Fs supplementation. Ducks were sacrificed on the 14th, 28th, and 42nd days from the beginning of administration and samples of abdominal fat, breast, and liver tissue were obtained. The concentrations of PCDD/Fs were analyzed in the samples to investigate their distribution and elimination in various duck tissues. The bioaccumulation of PCDD/Fs in ducks was found to be tissue-dependent. In the abdominal fat, the bioconcentration factor was negatively correlated with the degree of chlorination. Conversely, more chlorinated PCDD/Fs (hexa- or hepta-congeners) were associated with higher bioconcentration in the liver and breast tissue. In terms of the efficiency of PCDD/Fs elimination, the liver was found to be the fastest, followed by the breast and the abdominal fat. The clearance rate positively correlated with the degree of chlorination, as determined by comparing the apparent elimination rate constant (k) of PCDD/Fs in various tissues. Overall, lower k values observed in this study imply that mule ducks have a reduced clearance of PCDD/Fs in comparison with layer and broiler chickens.
Collapse
Affiliation(s)
- Ting-Wei Wu
- Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan.
| | - Jai-Wei Lee
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan.
| | - Hsueh-Yen Liu
- Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan.
| | - Wei-Hsiao Lin
- Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan.
| | - Chun-Yen Chu
- Graduate Institute of Animal Vaccine Technology, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan.
| | - Sheng-Lun Lin
- Supermicro Mass Research and Technology Center, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan; Center for General Education, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan.
| | - Guo Ping Chang-Chien
- Supermicro Mass Research and Technology Center, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan; Department of Cosmetics and Fashion styling, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan.
| | - Chi Yu
- Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan.
| |
Collapse
|
17
|
Tsou CH, Wu TW, Tung JC, Liang HC, Tuan PH, Chen YF. Generation of pseudonondiffracting optical beams with superlattice structures. Opt Express 2013; 21:23441-23449. [PMID: 24104258 DOI: 10.1364/oe.21.023441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate an approach to generate a class of pseudonondiffracting optical beams with the transverse shapes related to the superlattice structures. For constructing the superlattice waves, we consider a coherent superposition of two identical lattice waves with a specific relative angle in the azimuthal direction. We theoretically derive the general conditions of the relative angles for superlattice waves. In the experiment, a mask with multiple apertures which fulfill the conditions for superlattice structures is utilized to generate the pseudonondiffracting superlattice beams. With the analytical wave functions and experimental patterns, the pseudonondiffracting optical beams with a variety of structures can be generated systematically.
Collapse
|
18
|
Chen WH, Zhu X, Wu TW, Li RH. Defect solitons in two-dimensional optical lattices. Opt Express 2010; 18:10956-10961. [PMID: 20588951 DOI: 10.1364/oe.18.010956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We report on the existence and stability of solitons in a defect embedded in a square optical lattice based on a photorefractive crystal with focusing saturable nonlinearity. These solitons exist in different bandgaps due to the change of defect intensity. For a positive defect, the solitons only exist in the semi-infinite gap and can be stable in the low power region but not the high power region. For a negative defect, the solitons can exist not only in the semi-infinite gap, but also in the first gap. With increasing the defect depth, these solitons are stable within a moderate power region in the first gap while unstable in the entire semi-infinite gap.
Collapse
Affiliation(s)
- W H Chen
- Department of Physics, South China University of Technology, Guangzhou, 510640, China.
| | | | | | | |
Collapse
|
19
|
Wu TW, Cheng CYR, Zhang P. A direct mixed-body boundary element method for packed silencers. J Acoust Soc Am 2002; 111:2566-2572. [PMID: 12083187 DOI: 10.1121/1.1476920] [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: 05/23/2023]
Abstract
Bulk-reacting sound absorbing materials are often used in packed silencers to reduce broadband noise. A bulk-reacting material is characterized by a complex mean density and a complex speed of sound. These two material properties can be measured by the two-cavity method or calculated by empirical formulas. Modeling the entire silencer domain with a bulk-reacting lining will involve two different acoustic media, air and the bulk-reacting material. Traditionally, the interior silencer domain is divided into different zones and a multi-domain boundary element method (BEM) may be applied to solve the problem. However, defining different zones and matching the elements along each interface is tedious, especially when the zones are intricately connected. In this paper, a direct mixed-body boundary element method is used to model a packed silencer without subdividing it into different zones. This is achieved by summing up all the integral equations in different zones and then adding the hypersingular integral equations at interfaces. Several test cases, including a packed expansion chamber with and without an absorbing center bullet, and a parallel baffle silencer, are studied. Numerical results for the prediction of transmission loss (TL) are compared to experimental data.
Collapse
Affiliation(s)
- T W Wu
- Department of Mechanical Engineering, University of Kentucky, Lexington 40506, USA.
| | | | | |
Collapse
|
20
|
Abstract
The bioactivity of 3-methyl-1-phenyl-pyrazolin-5-one (MCI-186) was examined based on histochemical changes in drastic global ischemic rat brains. Rats with mean arterial blood pressure reduction were subjected to 60 min cerebral ischemia/80 min reperfusion. Infusion of MCI-186 at 3.0 mg/Kg reduced brain infarction from 21 +/- 4% (saline control, n= 15) to 11 +/- 3% (n=16, p<0.05). By comparison, infusion of up to 20 mg/Kg propyl galalate (PG)--a well documented antioxidant--produced an infarct percentage of 14 +/- 5% (n=8), close to the saline control. Biochemically, the neuroprotective effect of MCI-186 was demonstrated by diminishing the release of creatine kinase (CK) in serum from 3363 +/- 608 U/L (n=14) in saline control to 1989 +/- 293 U/L (n= 15) in MCI group (p<0.05), while PG did not lower the activity of CK significantly. MCI-186 behaves as a free radical scavenger by suppressing the formation of superoxide anion in xanthine oxidase (XO)-hypoxanthine (HP) system (p<0.05). Our data supported our contention that MCI-186 has potent anti-stroke effect with antioxidant activities.
Collapse
Affiliation(s)
- T W Wu
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto Western Hospital, Canada.
| | | | | | | |
Collapse
|
21
|
Kok LD, Wong YP, Wu TW, Chan HC, Kwok TT, Fung KP. Morin hydrate: a potential antioxidant in minimizing the free-radicals-mediated damage to cardiovascular cells by anti-tumor drugs. Life Sci 2000; 67:91-9. [PMID: 10896033 DOI: 10.1016/s0024-3205(00)00605-6] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The co-incubation of morin hydrate with either doxorubicin or mitomycin C could minimize the toxicity of these anti-tumor drugs on cardiovascular cells, such as red blood cells, human umbilical vein endothelial cells (ECV304) and primary mouse cardiomyocytes, whereas morin hydrate did not lower the cytotoxicity of the drugs on human hepatocellular carcinoma cells (HepG2). Morin hydrate may not exert its antioxidant effect by enhancing the antioxidant enzymatic activity because it did not cause any induction on the mRNA levels of manganese superoxide dismutase expression in ECV304 cells and HepG2 cells.
Collapse
Affiliation(s)
- L D Kok
- Department of Biochemistry, The Chinese University of Hong Kong, New Territories, Hong Kong Special Administrative Region
| | | | | | | | | | | |
Collapse
|
22
|
Lian WN, Tsai JW, Yu PM, Wu TW, Yang SC, Chau YP, Lin CH. Targeting of aminopeptidase N to bile canaliculi correlates with secretory activities of the developing canalicular domain. Hepatology 1999; 30:748-60. [PMID: 10462382 DOI: 10.1002/hep.510300302] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
We have used human hepatoma cell lines as an in vitro model to study the development of hepatic bile canaliculi (BC). Well-differentiated hepatoma cells cultured for 72 hours could develop characteristic spheroid structures at sites of cell-cell contact that contained tight junctions and various membrane protein markers, resembling BC found in vivo. Intact cytoskeleton was essential for this differentiation process. In the coculture experiments in which cells of different origins were populated together, BC only formed between hepatic cells and preferentially among well-differentiated cells. Poorly differentiated hepatoma cells never formed BC among themselves, but could be induced to undergo canalicular differentiation by interacting with well-differentiated cells. During BC morphogenesis, integral canalicular membrane proteins were gradually delivered and accumulated at the developing BC. Among them, targeting of aminopeptidase N (APN) seemed to correlate with activation of certain secretory functions. Specifically, only APN-positive BC supported excretion of fluorescein diacetate (FDA) and 70-kd dextran, but had no relationship with secretion of horseradish peroxidase (HRP). Targeting of another BC protein, dipeptidyl peptidase IV (DPPIV), on the other hand, bore no association with any secretory activity examined. In addition, inhibition of enzymatic activity of APN could perturb canalicular differentiation without affecting cell proliferation. Our results suggest that targeting of APN proteins may reflect or even play an important role in the development and functional maturation of the canalicular structures.
Collapse
Affiliation(s)
- W N Lian
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan
| | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
Cultured porcine aortic endothelial cells (PAEC) were exposed to four concentrations (0.00 mM - 5.00 mM) of 3-Morpholino-sydnonimine-hydrochloride (SIN-1, a nitric oxide donor). SIN-1 demonstrated a dose dependent cytotoxicity against PAEC as indicated by the thiobarbituric acid (TBA) assay. Morphologically and biochemically, the presence of selected flavonoids (morin, quercetin, or catechin) was shown to protect the PAEC from SIN-1 toxicity. Protection levels determined from the TBA assay were significant (p<0.05) for all flavonoids, with morin at 72+/-8%. Quercetin and catechin had comparable protective activities of 54+/-6% and 43+/-3%, respectively. This study supports the contention that SIN-1 is cytotoxic to PAEC and that antioxidants such as flavonoids may attenuate such toxicity.
Collapse
Affiliation(s)
- A Law
- Department of Clinical Biochemistry, University of Toronto, and Toronto Hospital, Canada
| | | | | | | |
Collapse
|
24
|
Perkins ME, Riojas YA, Wu TW, Le Blancq SM. CpABC, a Cryptosporidium parvum ATP-binding cassette protein at the host-parasite boundary in intracellular stages. Proc Natl Acad Sci U S A 1999; 96:5734-9. [PMID: 10318953 PMCID: PMC21929 DOI: 10.1073/pnas.96.10.5734] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [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: 11/18/2022] Open
Abstract
The intracellular parasite Cryptosporidium parvum develops inside a vacuole at the apex of its epithelial host cell. The developing parasite is separated from the host cell cytoplasm by a zone of attachment that consists of an extensively folded membranous structure known as the feeder organelle. It has been proposed that the feeder organelle is the site of regulation of transport of nutrients and drugs into the parasite. In this report, we localize an approximately 200-kDa integral membrane protein, CpABC, from Cryptosporidium parvum to the host-parasite boundary, possibly the feeder organelle. The predicted amino acid sequence of CpABC has significant structural similarity with the cystic fibrosis conductance regulator and the multidrug resistance protein subfamily of ATP-binding cassette proteins. This is an example of a parasite-encoded transport protein localized at the parasite-host interface of an intracellular protozoan.
Collapse
Affiliation(s)
- M E Perkins
- Division of Environmental Health Sciences, Joseph L. Mailman School of Public Health, Columbia University, New York, NY 10032, USA
| | | | | | | |
Collapse
|
25
|
Wu J, Sugiyama H, Zeng LH, Mickle D, Wu TW. Evidence of Trolox and some gallates as synergistic protectors of erythrocytes against peroxyl radicals. Biochem Cell Biol 1999; 76:661-4. [PMID: 10099788 DOI: 10.1139/bcb-76-4-661] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The peroxidation of human erythrocytes induced by peroxyl radical initiator and its inhibition by several gallate esters (e.g., propyl, methyl, ethyl) and Trolox (a more polar analogue of vitamin E) have been studied. The antioxidant activity was determined on erythrocytes against hemolysis generated by a thermal activator, 2,2'-azobis-(2-amidinopropane)dihydrogenchloride. It was found that propyl gallate and its two analogues were more effective than Trolox in preventing cell lysis. However, the combination of gallate esters and Trolox produced a protective effect exceeding the arithmetic sum of their individual contributions. These perceived synergisms occur at more than one level of Trolox at a given level of a gallate ester.
Collapse
Affiliation(s)
- J Wu
- Department of Laboratory Medicine and Pathobiology, University of Toronto, ON, Canada
| | | | | | | | | |
Collapse
|
26
|
Zeng LH, Wu J, Fung B, Tong JH, Mickle D, Wu TW. Comparative protection against oxyradicals by three flavonoids on cultured endothelial cells. Biochem Cell Biol 1998; 75:717-20. [PMID: 9599660 DOI: 10.1139/o97-062] [Citation(s) in RCA: 19] [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] Open
Abstract
Oxygen-derived free radicals are known to injure the endothelium of aorta in diverse disorders. In this study we compared the cytoprotective effects of three flavonoids against oxyradical damage to porcine aortic endothelial cells in vitro. Cultured porcine aortic endothelial cells were exposed to oxyradicals generated by xanthine oxidase--hypoxanthine (XO-HP). The cytoprotective activities of morin, quercetin, and catechin on these systems were compared using established morphologic criteria. The results in the XO-HP system showed that morin at 0.125, 0.25, and 0.5 mM delayed cell necrosis to 27.4 +/- 1.3, 46.8 +/- 1.8, and longer than 70 min, respectively, compared with 12.0 +/- 1.3 min in the control group. These degrees of protection were significantly stronger than those provided by quercetin and catechin at corresponding concentrations (p < 0.01). Morin and quercetin were moderate inhibitors of xanthine oxidase on the basis of the oxygen consumption rate, whereas catechin at the same concentrations had little inhibitory effect. The data from uric acid formation and cytochrome c reduction were consistent with the oxygen consumption measurement for the three flavonoids.
Collapse
Affiliation(s)
- L H Zeng
- Department of Clinical Biochemistry, University of Toronto, ON, Canada
| | | | | | | | | | | |
Collapse
|
27
|
Perkins ME, Wu TW, Le Blancq SM. Cyclosporin analogs inhibit in vitro growth of Cryptosporidium parvum. Antimicrob Agents Chemother 1998; 42:843-8. [PMID: 9559794 PMCID: PMC105553 DOI: 10.1128/aac.42.4.843] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [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] [Received: 10/16/1997] [Accepted: 02/04/1998] [Indexed: 02/07/2023] Open
Abstract
Cyclosporine and nonimmunosuppressive cyclosporin (CS) analogs were demonstrated to be potent inhibitors of the growth of the intracellular parasite Cryptosporidium parvum in short-term (48-h) in vitro cultures. Fifty-percent inhibitory concentrations (IC50s) were 0.4 microM for SDZ 033-243, 1.0 microM for SDZ PSC-833, and 1.5 microM for cyclosporine. Two other analogs were less effective than cyclosporine: the IC50 of SDZ 205-549 was 5 microM, and that of SDZ 209-313 was 7 microM. These were much lower than the IC50 of 85 microM of paromomycin, a standard positive control for in vitro drug assays for this parasite. In addition, intracellular growth of excysted sporozoites that had been incubated for 1 h in cyclosporine was significantly reduced, suggesting that the drug can inhibit sporozoite invasion. The cellular activities of the CS analogs used have been characterized for mammalian cells and protozoa. The two analogs that were most active in inhibiting C. parvum, SDZ PSC-833 and SDZ 033-243, bind weakly to cyclophilin, a peptidyl proline isomerase which is the primary target of cyclosporine and CS analogs. However, they are potent modifiers of the activity of the P glycoproteins/ multidrug resistance (MDR) transporters, members of the ATP-binding cassette (ABC) superfamily. Hence, both cyclophilin and some ABC transporters may be targets for this class of drugs, although drugs that preferentially interact with the latter are more potent. Cyclosporine (0.5 microM) had no significant chemosensitizing activity. That is, it did not significantly increase sensitivity to paromomycin, suggesting that an ABC transporter is not critical in the efflux of this drug. Cyclosporine at concentrations up to 50 microM was not toxic to host Caco-2 cells in the CellTiter 96 assay. The results of this study complement those of studies of the inhibitory effect of cyclosporine and CS analogs on other apicomplexan parasites, Plasmodium falciparum, Plasmodium vivax, and Toxoplasma gondii.
Collapse
Affiliation(s)
- M E Perkins
- Division of Environmental Health Sciences, Columbia University School of Public Health, New York, New York 10032, USA.
| | | | | |
Collapse
|
28
|
Zeng LH, Rootman DS, Burnstein A, Wu J, Wu TW. Morin hydrate: a better protector than purpurogallin of corneal endothelial cell damage induced by xanthine oxidase and SIN-1. Curr Eye Res 1998; 17:149-52. [PMID: 9523092 DOI: 10.1076/ceyr.17.2.149.5600] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
PURPOSE Free radicals are responsible for tissue injury in corneal preservation and transplantation. Morin hydrate, a flavonoid from Brazil wood, has been shown to be cytoprotective in several types of cells. The aim of this study was to investigate the effectiveness of morin hydrate on rabbit corneal endothelial cells against damage induced by oxyradicals and nitric oxide. METHODS Corneal endothelial cell cultures were prepared from New Zealand white rabbits, using standard microcarrier technique. Two free-radical-generating systems were used-17 IU/L xanthine oxidase/1 mM hypoxanthine and 5 mM 3-morpholinosydnonimine-N-ethylcarbamide (SIN-1, a nitric oxide-donating agent). RESULTS Over 95% of cultured corneal endothelial cells necrosed within 3.6 +/- 1.5 min after exposure to xanthine oxidase/hypoxanthine. Adding morin hydrate delayed cell necrosis to 5.8 +/- 0.3 min (0.25 mM morin hydrate), 13.3 +/- 5.0 min (0.5 mM), and 41.5 +/- 8.6 min (1.0 mM). Exposed to nitric oxide generated by SIN-1, cells necrosed by 9.5 +/- 2.5 min, versus 14.1 +/- 1.3 min (0.25 mM morin hydrate), 27.2 +/- 2.0 min (0.5 mM), and 43.3 +/- 5.4 min (1.0 mM). Morin hydrate significantly prolonged survival of cells compared to equimolar concentrations of purpurogallin, Trolox, or ascorbate (P < 0.01). CONCLUSION This study demonstrates that morin hydrate behaves as a broad-spectrum antioxidant: it scavenges not only xanthine oxidase/hypoxanthine-generated oxyradicals, but also nonenzymatic, nitrogen-derived radicals, better than those above mentioned antioxidants. This property of morin hydrate may help prevent free radical damage in corneal preservation solutions.
Collapse
Affiliation(s)
- L H Zeng
- Department of Ophthalmology, Toronto Hospital, University of Toronto, Ontario, Canada
| | | | | | | | | |
Collapse
|
29
|
Abstract
The cytoplasmic ribosomal RNA (rRNA) genes of the Apicomplexan protozoan parasite Cryptosporidium parvum have been analyzed with respect to size, copy number, organization and structure. The small and large subunit rRNAs are 1.7 and 3.6 kb, respectively. A 151 bp putative 5.8S rRNA gene was identified. The rDNA unit is 5' small subunit rRNA internal transcribed spacer 1-5.8S rRNA-internal transcribed spacer 2-large subunit rRNA 3'. There are five copies of the rDNA unit per haploid genome and they are not organized in a conventional head to tail tandem array with a conserved external transcribed spacer. The rDNA units are dispersed through the genome to at least three chromosomes. At least two of the rDNA units are single unlinked copies on different chromosomes. There are two structurally distinct types of rDNA unit, Type A and B, with marked differences in the internal transcribed spacer regions. There are four copies of the Type A rDNA unit and one copy of the Type B rDNA unit.
Collapse
MESH Headings
- Animals
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- Chromosome Mapping
- Cryptosporidium parvum/chemistry
- Cryptosporidium parvum/genetics
- Cytoplasm
- DNA, Protozoan/chemistry
- DNA, Protozoan/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Genes, Protozoan
- Genetic Markers
- Karyotyping
- Molecular Sequence Data
- RNA, Protozoan/chemistry
- RNA, Protozoan/genetics
- RNA, Ribosomal/chemistry
- RNA, Ribosomal/genetics
- Sequence Analysis
- Sequence Analysis, DNA
Collapse
Affiliation(s)
- S M Le Blancq
- Division of Environmental Health Sciences, Columbia University School of Public Health, New York, NY 10032, USA.
| | | | | | | | | |
Collapse
|
30
|
Wu TW, Zeng LH, Wu J, Fung KP, Weisel RD, Hempel A, Camerman N. Molecular structure and antioxidant specificity of purpurogallin in three types of human cardiovascular cells. Biochem Pharmacol 1996; 52:1073-80. [PMID: 8831727 DOI: 10.1016/0006-2952(96)00447-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Purpurogallin (PPG) in an active cytoprotector found in certain oak barks. We have shown that PPG prolongs the survival of cultured cardiocytes from rats and rabbits against different oxidants better than do antioxidants such as Trolox (a hydrophilic analogue of vitamin E) in a morphometric assay system. First, we verified by X-ray crystallography that PPG is a bicyclic molecule comprising a phenolic ring fused with a seven-membered ring in a highly planar conformation. In analogues of PPG wherein the two double bonds in the seven membered ring of the parent molecule are saturated or where the four OH groups of the parent compound are substituted by four OCH3 groups, the derivatives are less planar and less protective of the human cells than native PPG. Second, PPG in a concentration-dependent manner protected myocytes and endothelial cells of humans against oxyradicals generated with any one of the following oxyradical generators: (a) xanthine oxidase plus hypoxanthine, (b) menadione, or (c) paraquat. In each case, PPG was more cytoprotective than comparative antioxidants. Also, PPG protected erythrocytes against peroxyl radicals better than the two PPG derivatives mentioned. Third, the cytoprotective action of PPG detected in vitro was accompanied by declines of malondialdehyde. Finally, we observed that PPG chelated ferrous ions and, therefore, can suppress the formation of radicals in the Fenton reaction. Thus, PPG with its molecular architecture and presumably its affinity for ferrous ions protects multiple types of cardiovascular cells against oxyradicals.
Collapse
Affiliation(s)
- T W Wu
- Centre of Cardiovascular Research, University of Toronto, Ontario, Canada
| | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
We demonstrated, for the first time, that the flavonoid purpurogallin (PPG) at 0.2-0.5 mM inhibits DNA synthesis of murine fibrosarcoma L-929 and human U-87 MG glioblastoma cells in vitro. In the human U-87 MG glioblastoma cell experiments, we found that when cells were incubated with PPG at 0.5 mM for 0.5 and 24 h, about 25 and 50% inhibition of DNA compared with control were observed respectively. In contrast, 0.5 mM Trolox (a more polar analogue of vitamin E) did not inhibit DNA synthesis in both cell lines. These data indicate that PPG inhibits the synthesis of DNA in two distinct tumour cell lines.
Collapse
Affiliation(s)
- K P Fung
- Department of Clinical Biochemistry, University of Toronto, Canada
| | | | | |
Collapse
|
32
|
Abstract
We demonstrate here that both unconjugated bilirubin (Bu) and conjugated bilirubin (Bc) can protect human low density lipoprotein(LDL) against oxidation by oxyradicals generated by 2,2'-azo-bis (2 amidinopropane) dihydrochloride at 37 degrees. The oxidation was assessed by agarose gel electrophoresis and was further corroborated by assaying the malondialdehydes and lipid peroxides formed throughout oxidation. On a per mole basis, Bu and less so Bc was more effective than ascorbate in preventing LDL oxidation. Since oxidative modification of human LDL was implicated in plaque formation in blood vessels leading to atherogenesis, the data suggested that either bile pigment may help reduce the risk of atherogenesis.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry and Surgery, University of Toronto, Ontario, Canada
| | | | | | | | | |
Collapse
|
33
|
Abstract
We demonstrated that the flavonoid morin hydrate at 75-100 microM protects against the oxidation of low density lipoprotein (LDL) by free radicals produced by 2,2'-azo-bis(2-amidinopropane) dihydrochloride. Morin hydrate reduces the relative electrophoretic mobility, malondialdehyde equivalents and lipid peroxide level of oxidized LDL. On the other hand, Trolox (an analogue of vitamin E) showed less protective effect in the present system. Since free radical mediated oxidation of LDL is implicated to be a cause of atherogenesis, morin hydrate may be a candidate chemotherapeutic agent herein.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | | | | | | | |
Collapse
|
34
|
Zeng LH, Rootman DS, Fung KP, Wu TW. Comparative cytoprotection of cultured corneal endothelial cells by water-soluble antioxidants against free-radical damage. Cornea 1995; 14:509-14. [PMID: 8536465] [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: 01/31/2023]
Abstract
We reported previously that purpurogallin (PPG) markedly protects the cultured rabbit corneal endothelial cells (RCEC) against oxyradical damage generated with hypoxanthine (HX) and xanthine oxidase (XO)(1). In this study, we further compared the cytoprotective activities of PPG versus Trolox (TX, alpha-tocopherol, a water-soluble analogue of vitamin E) and ascorbate (Asc) in confluent cultured RCEC with phase contrast microscopy and confirmed by transmission electron microscopy. PPG prolonged survival of the oxyradical damaged cells longer than those without PPG present (18.6 +/- 1.4 min at 1.0 mM and 11.2 +/- 1.0 at 0.25 mM respectively vs. 7.3 +/- 0.8 min in control). At levels equimolar to PPG, TX, and Asc were less effective in delaying cell necrosis caused by HX and XO (p < 0.01). When exposed to superoxide radicals generated by menadione, RCEC necrosed at 29.8 +/- 1.5 min compared to PPG 47.2 +/- 1.0 min at 1.0 mM and 38.9 +/- 1.0 min at 0.25 mM. This was significantly different from TX and Asc at corresponding concentrations (p < 0.01). PPG scavenges not only HX-XO-generated oxyradicals, but also nonenzymatically produced superoxide radicals, more actively than two well known antioxidants--TX and Asc.
Collapse
Affiliation(s)
- L H Zeng
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | | | |
Collapse
|
35
|
Abstract
Oxidative modification of low density lipoprotein (LDL) has been suggested to be a risk factor for the development of atherosclerosis. Agents which can protect LDL from oxidation may be useful in preventing atherogenesis. Here, we found that morin hydrate, at 100 microM concentration, effectively inhibits Cu(2+)-induced oxidation of LDL. The oxidation of LDL was assessed by agarose gel electrophoresis. This was further studied by measuring the increased values of the malondialdehyde equivalents and the decreased numbers of reactive amino groups on oxidized LDL. Trolox, at equimolar concentrations, exhibit similar effects in preventing oxidation of LDL.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | | | |
Collapse
|
36
|
Abstract
Morin hydrate is a bioactive pigment found in yellow Brazil wood. Recently, we reported that morin hydrate prolongs the survival of three types of cells from the human circulatory system against oxyradicals generated in vitro. The protection excels that given by equimolar concentrations of ascorbate, mannitol, and Trolox. Here, we demonstrate that, in vivo, morin hydrate at 5 mumol/kg actually reduced by > 50% the tissue necrosis in post-ischemic and reperfused rabbit hearts. Mechanistically, morin hydrate not only scavenges oxyradicals, but also moderately inhibits xanthine oxidase, a free-radical generating enzyme from the ischemic endothelium. Among other possibilities, morin hydrate appears to chelate some metal ions (e.g. Fe2+) in oxyradical formation, although this needs to be examined further. Nuclear magnetic resonance (at 500 mHz) and electron-impact mass spectrometry also supported a molecular formula of C15H10O7 for morin hydrate. Only by X-ray crystallography was it clearly revealed that there are two water molecules attached by intermolecular hydrogen bonds to a morin molecule. Also, the three rings of morin hydrate approach coplanarity. This conformation favours a delocalization of electrons after oxyradical reduction, making morin an effective antioxidant. Thus, we have documented some of the molecular properties and myocardial salvage effects of morin hydrate.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | | | | | | | | | |
Collapse
|
37
|
Abstract
Oxygen-free radicals may injure the epithelium of corneas in storage awaiting transplantation. This study compared the cytoprotective effects of several antioxidants against oxygen-free radical injury to rabbit corneal epithelial cells in vitro. Cultured rabbit corneal epithelial cells were exposed to oxygen-free radicals generated by xanthine oxidase and hypoxanthine. The cytoprotective activities of various antioxidants on this system were compared using established morphologic criteria. The results demonstrated that purpurogallin at 1.0 mM delayed cell necrosis to 9.98 +/- 1.16 min compared with 2.96 +/- 0.67 min without antioxidant protection. This degree of protection was significantly different from that provided by ascorbate (1.0 mM), trolox (1.0 mM), superoxide dismutase + catalase, catalase (92,000 IU/L), mannitol (1.0 mM), and superoxide dismutase (24,200 IU/L) (p < 0.01). We concluded that purpurogallin effectively protects corneal epithelium from oxygen-free radical injury and may help prevent such injury in corneal preservation solutions.
Collapse
Affiliation(s)
- V H Yuen
- Department of Ophthalmology, University of Toronto, Ontario, Canada
| | | | | | | |
Collapse
|
38
|
Rootman DS, Bindish R, Zeng LH, Hasany SM, Wu TW. Purpurogallin as a cytoprotector of cultured rabbit corneal endothelium. Can J Ophthalmol 1994; 29:220-3. [PMID: 7859173] [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: 01/27/2023]
Abstract
We examined the protective properties of purpurogallin, a naturally occurring phenol, in delaying necrosis of cultured corneal endothelial cells caused by oxygen free radicals. Endothelial cell cultures were prepared from New Zealand white rabbits using microcarrier cell culture techniques. Corneal endothelial cells were treated with hypoxanthine (2 mM) and xanthine oxidase (67 IU/L) to generate free radicals. The criteria for cell necrosis were cytoplasmic shrinkage, dissolution of plasma membranes and presence of "haloes" around the cells on phase contrast microscopy, confirmed by transmission electron microscopy. More than 95% of second-generation cells exhibited morphologic evidence of necrosis within 4.62 +/- 0.82 minutes after exposure to oxyradicals. The addition of purpurogallin (0.25 or 1.0 mM) significantly increased time to cell necrosis to 8.18 +/- 0.83 and 11.59 +/- 1.71 minutes respectively (p < 0.05). Further studies are under way to determine whether purpurogallin may be useful in preventing endothelial cell damage in corneas preserved for corneal transplantation.
Collapse
Affiliation(s)
- D S Rootman
- Department of Ophthalmology, University of Toronto, Ont
| | | | | | | | | |
Collapse
|
39
|
Abstract
Recently, there has been renewed interest in propyl gallate, a preservative in foods and fuels. This compound, which exhibits antimicrobial activity, has been found to be toxicologically safe after almost 30 years of evaluation. In the present study, we examined whether propyl gallate is a hepatoprotective antioxidant, and investigated some of its bases of action vis-à-vis Trolox, a vitamin E analogue. In isolated rat hepatocytes, propyl gallate prolonged substantially cell survival against oxyradicals generated with xanthine oxidase-hypoxanthine. The protection was dose dependent and excelled that of Trolox, mannitol, or ascorbate, each at or near its optimum level in the same system. In rats undergoing an 80-min partial hepatic ischemia, infusion of propyl gallate at 20 mumol/kg body weight just before a 24-hr reperfusion salvaged the organ by 80.0 +/- 11.5%, an extent comparable to that with Trolox. Mechanistically, we found that propyl gallate (a) protected hepatocytes against the cascade of oxyradicals produced by xanthine oxidase-hypoxanthine; (b) protected hepatocytes against superoxide radicals generated specifically by menadione; (c) protected the functionally important hepatic vascular endothelial cells more effectively than Trolox against xanthine oxidase-hypoxanthine, and (d) approximately halved the amount of lipid conjugated dienes (a more specific marker of oxyradical damage than malondialdehyde) formed in tissues after oxidant damage. Therefore, there are fundamental reasons why propyl gallate is an effective antioxidant-based hepatoprotector, both in vitro and in vivo.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | | | | | |
Collapse
|
40
|
Wu TW, Zeng LH, Wu J, Fung KP. Morin: a wood pigment that protects three types of human cells in the cardiovascular system against oxyradical damage. Biochem Pharmacol 1994; 47:1099-103. [PMID: 8147911 DOI: 10.1016/0006-2952(94)90424-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Morin is a yellowish pigment extractable from the wood of Chlorophora tinctoria. In the present study, we have determined that morin protects three types of human cells--ventricular myocytes, saphenous vein endothelial cells, and erythrocytes--against damage by oxyradicals generated in situ. In myocytes and endothelial cells, morin prolonged substantially and in a concentration-dependent manner the survival of cells exposed to either xanthine oxidase-generated oxyradicals or superoxide radicals produced with menadione. Morin protected erythrocytes from lytic attack by peroxyl radicals generated with 2,2'-azo-bis (2-amidinopropane) dihydrochloride. In all three types of human cells, the protective effect of morin clearly excelled that displayed by Trolox (a vitamin E analog), ascorbate, or mannitol, which are water-soluble antioxidants of similar molecular size. Chemically, we verified that morin behaves as an antioxidant by diminishing markedly the amount of malondialdehyde (lipid peroxidation product) found in human cardiocytes despite their exposure to oxyradicals. In agreement with related reports, we also observed that morin is non-toxic in rats even when used at concentrations 2-3 orders of magnitude higher than those in our in vitro studies. Thus, morin acts as a broad-spectrum and non-toxic antioxidant.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Toronto General Hospital, Ontario, Canada
| | | | | | | |
Collapse
|
41
|
Abstract
Cultured rat glomerular mesangial cells were damaged when exposed to oxyradicals generated either from xanthine oxidase plus hypoxanthine, or by superoxide radicals formed from menadione. Morin hydrate is an antioxidant extracted from yellow Brazil wood. When morin hydrate was added to cultured rat glomerular mesangial cells which were attacked by oxyradicals generated by xanthine oxidase plus hypoxanthine, the survival time of the cells was doubled. However, this protective effect of morin hydrate was less marked when the cells were attacked by menadione. Note that the protective effects of Trolox which is a polar analogue of vitamin E were miniscule relative to those of morin hydrate with both oxidants.
Collapse
Affiliation(s)
- L H Zeng
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | |
Collapse
|
42
|
Abstract
Oxidative modification of human low density lipoprotein (LDL) has been implicated in plaque formation in blood vessels leading to atherogenesis. Conversely, there is increasing evidence that prevention of LDL oxidation reduces the incidence of coronary artery disease. Here, we have compared the effect of unconjugated bilirubin (Bu) and Trolox (a vitamin E analogue) on the oxidation of LDL after treatment with Cu2+ under defined conditions. We observed that Bu, at or near the normal serum level (i.e. 17 microM) effectively inhibits oxidation of LDL, while it takes at least 500 microM Trolox to achieve a similar effect. This means that, on a per mole basis, Bu is > 20 times more effective than Trolox in preventing LDL oxidation. The oxidation of LDL was assessed by agarose gel electrophoresis. This was further corroborated by assaying the malondialdehyde formed upon reacting the presumptive peroxidation product(s) of LDL with thiobarbituric acid. Thus, we have directly verified that Bu and, less so, Trolox, can each prevent the oxidative damage of LDL in vitro. Our result supports the contention that Bu as an endogenous antioxidant can prevent LDL oxidation and hence reduce the risk of atherogenesis.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | |
Collapse
|
43
|
|
44
|
Fung KP, Wu TW, Zeng LH, Wu J. The opposing effects of an inhibitor of nitric oxide synthesis and of a donor of nitric oxide in rabbits undergoing myocardial ischemia reperfusion. Life Sci 1994; 54:PL491-6. [PMID: 8208056 DOI: 10.1016/0024-3205(94)00722-5] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We observed that N-nitro-L-arginine (NOLA), a nitric oxide biosynthesis inhibitor, exacerbated necrosis in the rabbit heart during ischemia-reperfusion while 3-morpholino-sydnonimine-hydrochloride (SIN-1) (a nitric oxide donor) reduced myocardial damage in the same model. In rabbits undergoing 1-h ligation of the anterior ventricular coronary artery, a single bolus injection of NOLA (30 mg/kg) or continuous infusion of SIN-1 (3 mg/kg) were introduced into the post-ischemic heart immediately before 4-h reperfusion. Against negligible necrosis in 6 sham-operated control animals, and 33.8 (SD 13.5)% necrosis in the area at risk for the saline control group (n = 8), the NOLA-treated group (n = 8) had a necrosis of 44.3 (SD 8.6)% whereas the SIN-1-treated group (n = 10) showed a necrosis of 16.8 (SD 4.9)% (both with p < 0.05 vs saline control group). The pressure-rate index increased in the NOLA-treated group but decreased in the SIN-1-treated group. These data support the contention that a nitric oxide donor is an effective cardioprotector during ischemia-reperfusion in vivo.
Collapse
Affiliation(s)
- K P Fung
- Department of Clinical Biochemistry, University of Toronto, Canada
| | | | | | | |
Collapse
|
45
|
Abstract
We observed that purpurogallin (PPG) which is a flavonoid markedly protects the rabbit against myocardial ischemia-reperfusion injury. In rabbits undergoing 1-h ligation of the anterior ventricular coronary artery, a bolus infusion of PPG was introduced into the post-ischemic heart immediately before 3-h reperfusion. Against negligible necrosis in 6 sham-operated controls, and 41.7 (SD 11.3)% necrosis in the area at risk for the placebo control group (n = 14 animals), the PPG-treated groups (n = 6, 6, 14) had a necrosis of 26.8 (6.4)%, 10.8 (3.5)%, and 11.7 (5.2)% at doses of 2.5, 5, and 10 mumol/kg, respectively (each with p < 0.01 vs control value). By comparison, infusion of Trolox (a vitamin E analogue) at 5 mumol/kg produced a higher necrosis of 17.7 +/- 7.2% (n = 6, p < 0.05 vs value obtained from 5 mumol/kg PPG-treated group) in the same model. Note that myocardial necrosis was estimated by tetrazolium-based histochemistry and confirmed by light and transmission electron microscopies. These data support our contention that PPG is an effective cardioprotector, whose mechanism of action will be reported separately.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Canada
| | | | | | | | | | | |
Collapse
|
46
|
Wu TW. Is serum bilirubin a risk factor for coronary artery disease? Clin Chem 1994; 40:9-10. [PMID: 8287550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
47
|
Wu TW, Zeng LH, Fung KP, Wu J, Pang H, Grey AA, Weisel RD, Wang JY. Effect of sodium tanshinone IIA sulfonate in the rabbit myocardium and on human cardiomyocytes and vascular endothelial cells. Biochem Pharmacol 1993; 46:2327-32. [PMID: 8274165 DOI: 10.1016/0006-2952(93)90624-6] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Sodium tanshinone IIA sulfonate (STS) is a derivative of tanshinone IIA. The latter is a pharmacologically active component isolated from the rhizome of the Chinese herb Salvia miltiorrhiza. Liquid chromatographically pure STS was found to reduce myocardial infarct size by 53.14 +/- 22.79% relative to that in the saline control in a rabbit 1 hr-ischemia and 3 hr-reperfusion model. This effect was comparable to that of Trolox (a better characterized antioxidant serving as a reference cytoprotector), which salvaged the myocardium in the same infarct model by 62.13 +/- 18.91%. Also, like Trolox, STS did not inhibit oxygen uptake by xanthine oxidase (XO), a key enzyme in free radical generation. However, in contrast to Trolox, STS significantly prolonged the survival of cultured human saphenous vein endothelial cells but not human ventricular myocytes in vitro when these cells were separately exposed to XO-generated oxyradicals. Note that the endothelium is recognized to be a key site of oxidant generation and attack. Our findings in vitro and in vivo support the interpretation that STS is a cardioprotective substance, and that it may exert a beneficial effect on the clinically important vascular endothelium.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | | | | | | | | | | | |
Collapse
|
48
|
Zielenski J, Wu TW, Fung KP, Zeng LH, Li RK, Mickle DA, Wu J. Chemical syntheses of Trolox conjugates which protect human ventricular myocytes against in situ-generated oxyradicals. Eur J Pharmacol 1993; 248:313-8. [PMID: 7514137 DOI: 10.1016/0926-6917(93)90005-b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Synthetic conjugates of the antioxidant Trolox (6-hydroxy-2,5,7,8-tetramethyl chroman-2-carboxylic acid) have been prepared by coupling it with 1-ethyl-3-(3-dimethyl-amino-propyl) carbodiimide hydrochloride either to p-aminophenyl-beta-D-lactopyranoside, or to higher molecular weight ligands such as dextran and polylysine. Compared to Trolox and on a mole to mole basis, dextran-Trolox is almost equally active, while lactosylphenyl- and polylysine-Trolox conjugates are distinctly more active in preventing the damage on human ventricular myocytes by oxyradicals generated from xanthine oxidase-hypoxanthine. Listed in order of decreasing cytoprotective activity, they are: lactosylphenyl-Trolox >> polylysine-Trolox > Trolox > dextran-Trolox. Thus, Trolox can be chemically modified by coupling it to one of a number of ligands and, in some cases, with resultant increases in its ability to protect human ventricular myocytes from oxyradical damage.
Collapse
Affiliation(s)
- J Zielenski
- Department of Clinical Biochemistry, University of Toronto, Ontario, Canada
| | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
OBJECTIVE The aim was to determine if lactosylphenyl Trolox could improve myocardial resistance to ischaemia and reperfusion. Lactosylphenyl Trolox is derived by coupling p-aminophenyl-beta-D-lactopyranoside to Trolox. Trolox, a polar analogue of vitamin E, has been found to protect human cardiomyocytes against oxyradicals and to reduce myocardial damage by 66% in a canine ischaemia-reperfusion model. METHODS New Zealand white rabbits (weighing approximately 3.5 kg) were subjected to 1 h ischaemia by ligation of the main branch of the anterior ventricular coronary artery. Approximately 1-2 min before release of ischaemia, a 30 ml bolus of saline (placebo control) or saline containing lactosylphenyl Trolox was injected into the right external jugular vein, followed by 3 h reperfusion. The area at risk was identified by staining with Evans Blue. Area of necrosis was indicated by tetrazolium red staining, confirmed by histopathology and quantified by planimetry. RESULTS The control group (n = 6) had 46.6(SD 10.0)% necrosis of the area at risk but the lactosylphenyl Trolox treated groups (n = 6 per group) had reduced necrosis: 34.0(6.5)%, 17.4(8.2)%, and 6.9(3.6)% at doses of 2.5, 5.0, and 10 mumol.kg-1, respectively (each with p < 0.05 v control value). These translated to 48.6(14.0)%, 62.7(17.6)%, and 85.3(7.8)% myocardial salvage, respectively. In contrast, the salvages achieved with 2.5 and 10 mumol.kg-1 of Trolox were 31.0(11.0)% and 62.1(18.9)% respectively (both p < 0.05 v lactosylphenyl Trolox). CONCLUSIONS Lactosylphenyl Trolox reduces myocardial infarct size more effectively than Trolox in a rabbit model of ischaemia-reperfusion.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto Faculty of Medicine, Toronto General Hospital, Ontario, Canada
| | | | | | | | | | | |
Collapse
|
50
|
Abstract
Morin hydrate, or simply morin, is shown here to be an effective hepatoprotector in vitro and in vivo. Between 0.25-2.0 mM, morin prolongs survival of rat hepatocytes against free radical damage triggered by xanthine oxidase-hypoxanthine, and substantially better than equimolar concentrations of Trolox (a vitamin E analogue), mannitol, and ascorbate. In a rat model of 80 min ischemia-24 h reperfusion in the liver, infusion of morin at 2.5, 5.0 and 10 mumol/Kg body weight before reperfusion reduces liver necrosis in the placebo control by 51.48 +/- 9.94%, 66.55 +/- 2.18%, and 79.37 +/- 11.03%, respectively, for n = 6 per group. Mechanistically, morin acts in a two-pronged manner: as a preventive antioxidant by partially inhibiting xanthine oxidase and partly as a curative antioxidant by scavenging oxyradicals. The role of morin as an effective free radical scavenger is further evidenced by its ability to protect human red cell membrane from peroxidative attack better than ascorbate, Trolox, and mannitol. Collectively, our data demonstrate that morin is an effective hepatoprotector, both in cultured cells and in hepatic ischemia-reperfusion.
Collapse
Affiliation(s)
- T W Wu
- Department of Clinical Biochemistry, University of Toronto, Canada
| | | | | | | |
Collapse
|