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Liu B, Zhang C, Deng J, Zhang B, Chen F, Chen W, Fang X, Li J, Zu K, Bu W. Response of tree growth to nutrient addition is size dependent in a subtropical forest. Sci Total Environ 2024; 923:171501. [PMID: 38447724 DOI: 10.1016/j.scitotenv.2024.171501] [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: 12/27/2023] [Revised: 03/03/2024] [Accepted: 03/03/2024] [Indexed: 03/08/2024]
Abstract
Understanding how nutrient addition affects the tree growth is critical for assessing forest ecosystem function and processes, especially in the context of increased nitrogen (N) and phosphorus (P) deposition. Subtropical forests are often considered N-rich and P-poor ecosystems, but few existing studies follow the traditional "P limitation" paradigm, possibly due to differences in nutrient requirements among trees of different size classes. We conducted a three-year fertilization experiment with four treatments (Control, N-treatment, P-treatment, and NP-treatment). We measured soil nutrient availability, leaf stoichiometry, and relative growth rate (RGR) of trees across three size classes (small, medium and large) in 64 plots. We found that N and NP-treatments increased the RGR of large trees. P-treatment increased the RGR of small trees. RGR was mainly affected by N addition, the total effect of P addition was only 10 % of that of N addition. The effect of nutrient addition on RGR was mainly regulated by leaf stoichiometry. This study reveals that nutrient limitation is size dependent, indicating that continuous unbalanced N and P deposition will inhibit the growth of small trees and increase the instability of subtropical forest stand structure, but may improve the carbon sink function of large trees.
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Affiliation(s)
- Bin Liu
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, Jiangxi Provincial Key Laboratory of Conservation Biology, College of Forestry, Jiangxi Agricultural University, Nanchang 330045, China; Key Laboratory of Forest Ecology and Environment of the National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing 100091, China
| | - Cancan Zhang
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, Jiangxi Provincial Key Laboratory of Conservation Biology, College of Forestry, Jiangxi Agricultural University, Nanchang 330045, China; Jiulianshan National Observation and Research Station of Chinese Forest Ecosystem, Jiangxi Agricultural University, Nanchang 330045, China
| | - Jun Deng
- Administration of Jiulianshan National Nature Reserve, Ganzhou 341799, China
| | - Bowen Zhang
- Administration of Jiulianshan National Nature Reserve, Ganzhou 341799, China
| | - Fusheng Chen
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, Jiangxi Provincial Key Laboratory of Conservation Biology, College of Forestry, Jiangxi Agricultural University, Nanchang 330045, China; Jiulianshan National Observation and Research Station of Chinese Forest Ecosystem, Jiangxi Agricultural University, Nanchang 330045, China
| | - Wei Chen
- Administration of Jiulianshan National Nature Reserve, Ganzhou 341799, China
| | - Xiangmin Fang
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, Jiangxi Provincial Key Laboratory of Conservation Biology, College of Forestry, Jiangxi Agricultural University, Nanchang 330045, China
| | - Jianjun Li
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, Jiangxi Provincial Key Laboratory of Conservation Biology, College of Forestry, Jiangxi Agricultural University, Nanchang 330045, China
| | - Kuiling Zu
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, Jiangxi Provincial Key Laboratory of Conservation Biology, College of Forestry, Jiangxi Agricultural University, Nanchang 330045, China
| | - Wensheng Bu
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, Jiangxi Provincial Key Laboratory of Conservation Biology, College of Forestry, Jiangxi Agricultural University, Nanchang 330045, China; Jiulianshan National Observation and Research Station of Chinese Forest Ecosystem, Jiangxi Agricultural University, Nanchang 330045, China.
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Zhang L, Liu X, Sun Z, Bu W, Bongers FJ, Song X, Yang J, Sun Z, Li Y, Li S, Cao M, Ma K, Swenson NG. Functional trait space and redundancy of plant communities decrease toward cold temperature at high altitudes in Southwest China. Sci China Life Sci 2023; 66:376-384. [PMID: 35876972 DOI: 10.1007/s11427-021-2135-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/31/2022] [Indexed: 12/01/2022]
Abstract
Plant communities in mountainous areas shift gradually as climatic conditions change with altitude. How trait structure in multivariate space adapts to these varying climates in natural forest stands is unclear. Studying the multivariate functional trait structure and redundancy of tree communities along altitude gradients is crucial to understanding how temperature change affects natural forest stands. In this study, the leaf area, specific leaf area, leaf carbon, nitrogen, and phosphorous content from 1,590 trees were collected and used to construct the functional trait space of 12 plant communities at altitudes ranging from 800 m to 3,800 m across three mountains. Hypervolume overlap was calculated to quantify species trait redundancy per community. First, hypervolumes of species exclusion and full species set were calculated, respectively. Second, the overlap between these two volumes was calculated to obtain hypervolume overlap. Results showed that the functional trait space significantly increased with mean annual temperature toward lower altitudes within and across three mountains, whereas species trait redundancy had different patterns between mountains. Thus, warming can widen functional trait space and alter the redundancy in plant communities. The inconsistent patterns of redundancy between mountains suggest that warming exerts varying influences on different ecosystems. Identification of climate-vulnerable ecosystems is important in the face of global warming.
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Affiliation(s)
- Lan Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Xiaojuan Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
| | - Zhenhua Sun
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
| | - Wensheng Bu
- Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, College of Forestry, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Franca J Bongers
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Xiaoyang Song
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
| | - Jie Yang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
| | - Zhenkai Sun
- Key Laboratory of Tree Breeding and Cultivation, Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Yin Li
- Fujian Provincial Key Laboratory of Resources and Environmental Monitoring and Sustainable Management and Utilization, Sanming University, Sanming, 365004, China
| | - Shan Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Min Cao
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
| | - Keping Ma
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
| | - Nathan G Swenson
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
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Liu B, Bu W, Zang R. Improved allometric models to estimate the aboveground biomass of younger secondary tropical forests. Glob Ecol Conserv 2023. [DOI: 10.1016/j.gecco.2022.e02359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Beugnon R, Bu W, Bruelheide H, Davrinche A, Du J, Haider S, Kunz M, von Oheimb G, Perles‐Garcia MD, Saadani M, Scholten T, Seitz S, Singavarapu B, Trogisch S, Wang Y, Wubet T, Xue K, Yang B, Cesarz S, Eisenhauer N. Abiotic and biotic drivers of tree trait effects on soil microbial biomass and soil carbon concentration. ECOL MONOGR 2022. [DOI: 10.1002/ecm.1563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Rémy Beugnon
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Leipzig Institute for Meteorology, Universität Leipzig, Stephanstraße 3 Leipzig Germany
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 1919, route de Mende Montpellier Cedex 5 France
| | - Wensheng Bu
- College of Forestry Jiangxi Agricultural University Nanchang China
| | - Helge Bruelheide
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle‐Wittenberg, Am Kirchtor 1 Halle Germany
| | - Andréa Davrinche
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle‐Wittenberg, Am Kirchtor 1 Halle Germany
| | - Jianqing Du
- College of Resources and Environment, University of Chinese Academy of Sciences Beijing China
- Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of Sciences Beijing China
| | - Sylvia Haider
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle‐Wittenberg, Am Kirchtor 1 Halle Germany
| | - Matthias Kunz
- Institute of General Ecology and Environmental Protection, Technische Universität Dresden, Pienner Strasse 7 Tharandt Germany
| | - Goddert von Oheimb
- Institute of General Ecology and Environmental Protection, Technische Universität Dresden, Pienner Strasse 7 Tharandt Germany
| | - Maria D. Perles‐Garcia
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle‐Wittenberg, Am Kirchtor 1 Halle Germany
| | - Mariem Saadani
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle‐Wittenberg, Am Kirchtor 1 Halle Germany
| | - Thomas Scholten
- Institute of Geography, University of Tübingen, Rümelinstrasse 19‐23 Tübingen Germany
| | - Steffen Seitz
- Institute of Geography, University of Tübingen, Rümelinstrasse 19‐23 Tübingen Germany
| | - Bala Singavarapu
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle‐Wittenberg, Am Kirchtor 1 Halle Germany
- UFZ‐Helmholtz Centre for Environmental Research, Department of Community Ecology, Theodor‐Lieser‐Strasse 4 Halle (Saale) Germany
| | - Stefan Trogisch
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle‐Wittenberg, Am Kirchtor 1 Halle Germany
| | - Yanfen Wang
- College of Resources and Environment, University of Chinese Academy of Sciences Beijing China
- Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of Sciences Beijing China
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Chinese Academy of Sciences Beijing China
| | - Tesfaye Wubet
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- UFZ‐Helmholtz Centre for Environmental Research, Department of Community Ecology, Theodor‐Lieser‐Strasse 4 Halle (Saale) Germany
| | - Kai Xue
- College of Resources and Environment, University of Chinese Academy of Sciences Beijing China
- Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of Sciences Beijing China
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Chinese Academy of Sciences Beijing China
| | - Bo Yang
- Jiangxi Key Laboratory of Plant Resources and Biodiversity Jingdezhen University Jingdezhen China
| | - Simone Cesarz
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology, Leipzig University, Puschstrasse 4 Leipzig Germany
| | - Nico Eisenhauer
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, Puschstrasse 4 Leipzig Germany
- Institute of Biology, Leipzig University, Puschstrasse 4 Leipzig Germany
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Li X, Xue Z, Chen X, Qiao X, Mo G, Bu W, Guan B, Wang T. Printable assemblies of perovskite nanocubes on meter-scale panel. Sci Adv 2022; 8:eadd1559. [PMID: 36367933 PMCID: PMC9651854 DOI: 10.1126/sciadv.add1559] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/26/2022] [Indexed: 06/16/2023]
Abstract
Hierarchical assemblies of functional nanoparticles can have applications exceeding those of individual constituents. Arranging components in a certain order, even at the atomic scale, can result in emergent effects. We demonstrate that printed atomic ordering is achieved in multiscale hierarchical structures, including nanoparticles, superlattices, and macroarrays. The CsPbBr3 perovskite nanocubes self-assemble into superlattices in ordered arrays controlled across 10 scales. These structures behave as single nanoparticles, with diffraction patterns similar to those of single crystals. The assemblies repeat as two-dimensional planar unit cells, forming crystalline superlattice arrays. The fluorescence intensity of these arrays is 5.2 times higher than those of random aggregate arrays. The multiscale coherent states can be printed on a meter-scale panel as a micropixel light-producing layer of primary-color photon emitters. These hierarchical assemblies can boost the performance of optoelectronic devices and enable the development of high-efficiency, directional quantum light sources.
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Affiliation(s)
- Xiao Li
- Life and Health Intelligent Research Institute, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China
| | - Zhenjie Xue
- Life and Health Intelligent Research Institute, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China
| | - Xiangyu Chen
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Xuezhi Qiao
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Guang Mo
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Wensheng Bu
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Bo Guan
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Tie Wang
- Life and Health Intelligent Research Institute, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China
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Trogisch S, Liu X, Rutten G, Xue K, Bauhus J, Brose U, Bu W, Cesarz S, Chesters D, Connolly J, Cui X, Eisenhauer N, Guo L, Haider S, Härdtle W, Kunz M, Liu L, Ma Z, Neumann S, Sang W, Schuldt A, Tang Z, van Dam NM, von Oheimb G, Wang MQ, Wang S, Weinhold A, Wirth C, Wubet T, Xu X, Yang B, Zhang N, Zhu CD, Ma K, Wang Y, Bruelheide H. The significance of tree-tree interactions for forest ecosystem functioning. Basic Appl Ecol 2021. [DOI: 10.1016/j.baae.2021.02.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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7
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Wang J, Defrenne C, McCormack ML, Yang L, Tian D, Luo Y, Hou E, Yan T, Li Z, Bu W, Chen Y, Niu S. Fine-root functional trait responses to experimental warming: a global meta-analysis. New Phytol 2021; 230:1856-1867. [PMID: 33586131 DOI: 10.1111/nph.17279] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [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: 09/12/2020] [Accepted: 02/03/2021] [Indexed: 05/12/2023]
Abstract
Whether and how warming alters functional traits of absorptive plant roots remains to be answered across the globe. Tackling this question is crucial to better understanding terrestrial responses to climate change as fine-root traits drive many ecosystem processes. We carried out a detailed synthesis of fine-root trait responses to experimental warming by performing a meta-analysis of 964 paired observations from 177 publications. Warming increased fine-root biomass, production, respiration and nitrogen concentration as well as decreased root carbon : nitrogen ratio and nonstructural carbohydrates. Warming effects on fine-root biomass decreased with greater warming magnitude, especially in short-term experiments. Furthermore, the positive effect of warming on fine-root biomass was strongest in deeper soil horizons and in colder and drier regions. Total fine-root length, morphology, mortality, life span and turnover were unresponsive to warming. Our results highlight the significant changes in fine-root traits in response to warming as well as the importance of warming magnitude and duration in understanding fine-root responses. These changes have strong implications for global soil carbon stocks in a warmer world associated with increased root-derived carbon inputs into deeper soil horizons and increases in fine-root respiration.
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Affiliation(s)
- Jinsong Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
- Department of Biological Sciences, Center for Ecosystem Sciences and Society, Northern Arizona University, Flagstaff, AZ, 86001, USA
| | - Camille Defrenne
- Climate Change Science Institute and Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - M Luke McCormack
- Center for Tree Science, The Morton Arboretum, 4100 Illinois Rt. 53, Lisle, IL, 60532, USA
| | - Lu Yang
- Research Center of Forest Management Engineering of State Forestry and Grassland Administration, Beijing Forestry University, Beijing, 100083, China
| | - Dashuan Tian
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yiqi Luo
- Department of Biological Sciences, Center for Ecosystem Sciences and Society, Northern Arizona University, Flagstaff, AZ, 86001, USA
| | - Enqing Hou
- Department of Biological Sciences, Center for Ecosystem Sciences and Society, Northern Arizona University, Flagstaff, AZ, 86001, USA
| | - Tao Yan
- State Key Laboratory of Grassland and Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730000, China
| | - Zhaolei Li
- National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Key Laboratory of Agricultural Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian, 271018, China
| | - Wensheng Bu
- College of Forestry, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Ye Chen
- Department of Mathematics and Statistics, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Shuli Niu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
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Zhao R, Bu W, Chen Y, Chen X. The Dose-Response Associations of Sedentary Time with Chronic Diseases and the Risk for All-Cause Mortality Affected by Different Health Status: A Systematic Review and Meta-Analysis. J Nutr Health Aging 2020; 24:63-70. [PMID: 31886810 DOI: 10.1007/s12603-019-1298-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE To determine the dose-response associations of sedentary behaviour with cardiovascular diseases (CVD), cancer, and all-cause mortality, and to examine whether the sedentary-associated all-cause mortality risk was affected by appearance of diabetes and hypertension, physical activity, and body mass index (BMI). DESIGN We carried out a systematic review and meta-analysis to search Medline, SportDiscus, and Web of Science for eligible studies. SETTINGS Prospective cohort studies that reported sedentary time and CVD, cancer, and mortality incidents. MEASUREMENTS Two authors independently extracted data based on predefined criteria. The effect estimates were evaluated by hazard ratios (HRs) with 95% confidences (CIs). RESULTS Twenty-four studies met the inclusion criteria. Sitting time showed dose-response associations with CVD, cancer, and all-cause mortality, with each 1-hour increment of sitting time daily accounting for HRs 1.04 (95% CIs 1.02-1.07), 1.01 (1.00-1.02), and 1.03 (1.02-1.03), respectively. The link between sitting time and CVD and all-cause mortality was non-linear (pnon-linear < 0.0001). The relationship between TV viewing and CVD and all-cause mortality was dose-dependent, with HRs 1.07 (1.06-1.09) and 1.04 (1.01-1.06) for per 1-hour increment of TV time every day, respectively. The regression was curved (pnon-linear < 0.0001). When the analysis was stratified by the percentage of diabetes and hypertension, BMI values, and physical activity levels, we found that higher BMI and a greater percentage of diabetes and hypertension further increased all-cause mortality risk in the most sedentary populations, whereas higher physical activity levels decreased it. CONCLUSION Sitting time and TV viewing significantly increased cardiovascular, cancer, and mortality risk; the associations were dose-dependent. More importantly, sedentary behaviour in combination with chronic diseases or high BMI increased all-cause mortality risk whereas physical activity was likely to alleviate the adverse associations.
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Affiliation(s)
- R Zhao
- Renqing Zhao, Yangzhou University, College of Physical Education, 88 Daxue South Road, Yangzhou, Jiangsu 225009, China. Tel: 8651487972015.
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Hodgman SS, Bu W, Mann SB, Khakimov RI, Truscott AG. Higher-Order Quantum Ghost Imaging with Ultracold Atoms. Phys Rev Lett 2019; 122:233601. [PMID: 31298918 DOI: 10.1103/physrevlett.122.233601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/04/2019] [Indexed: 06/10/2023]
Abstract
Ghost imaging is a quantum optics technique that uses correlations between two beams to reconstruct an image from photons that do not interact with the object being imaged. While pairwise (second-order) correlations are usually used to create the ghost image, higher-order correlations can be utilized to improve the performance. In this Letter, we demonstrate higher-order atomic ghost imaging, using entangled ultracold metastable helium atoms from an s-wave collision halo. We construct higher-order ghost images up to fifth order and show that using higher-order correlations can improve the visibility of the images without impacting the resolution. This is the first demonstration of higher-order ghost imaging with massive particles and the first higher-order ghost imaging protocol of any type using a quantum source.
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Affiliation(s)
- S S Hodgman
- Research School of Physics and Engineering, Australian National University, Canberra 2601, Australia
| | - W Bu
- Research School of Physics and Engineering, Australian National University, Canberra 2601, Australia
| | - S B Mann
- Research School of Physics and Engineering, Australian National University, Canberra 2601, Australia
| | - R I Khakimov
- Research School of Physics and Engineering, Australian National University, Canberra 2601, Australia
| | - A G Truscott
- Research School of Physics and Engineering, Australian National University, Canberra 2601, Australia
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Bu W, Huang J, Xu H, Zang R, Ding Y, Li Y, Lin M, Wang J, Zhang C. Plant Functional Traits Are the Mediators in Regulating Effects of Abiotic Site Conditions on Aboveground Carbon Stock-Evidence From a 30 ha Tropical Forest Plot. Front Plant Sci 2019; 9:1958. [PMID: 30687357 PMCID: PMC6333873 DOI: 10.3389/fpls.2018.01958] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 12/17/2018] [Indexed: 06/09/2023]
Abstract
Understanding the relative contribution of abiotic and biotic factors to the formation of ecosystem functioning across scales is vital to evaluate ecosystem services. Here, we elucidate the effects of abiotic site conditions (i.e., soil and topographic properties) and plant functional traits on variations of stand aboveground carbon (AGC) stock in an old-growth tropical montane rain forest. The response-effect framework in functional ecology is adopted in examining how plant functional traits respond to environmental changes and affect ecosystem functioning. We measured specific leaf area and wood density of 270 woody plant species and estimated stand AGC stocks in a 30-ha forest plot. The relationships among environmental factors (ENVIRONMENT), community-weighted means of functional traits (TRAITS) and stand AGC stocks across nested spatial scales were disentangled by structural equation modeling. The results showed that the stands composed of 'acquisitive' species (high specific leaf area and low wood density) had low AGC, whereas stands composed of 'conservative' species (low specific leaf area and high wood density) had high AGC. TRAITS responded to ENVIRONMENT and affected AGC directly. ENVIRONMENT had an indirect effect on AGC through its direct effect on TRAITS. TRAITS were more important than ENVIRONMENT in driving variations of AGC. The effects of TRAITS on AGC increased, while the effects of ENVIRONMENT on AGC decreased with the increase of spatial scales in the tropical montane rain forest. Our study suggests that plant functional traits are the mediators in regulating effects of abiotic site conditions on ecosystem functions.
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Affiliation(s)
- Wensheng Bu
- 2011 Collaborative Innovation Center of Jiangxi Typical Trees Cultivation and Utilization, Jiulianshan National Observation and Research Station of Chinese Forest Ecosystem, College of Forestry, Jiangxi Agricultural University, Nanchang, China
- Key Laboratory of Forest Ecology and Environment of State Forestry Administration, Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing, China
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Jihong Huang
- Key Laboratory of Forest Ecology and Environment of State Forestry Administration, Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing, China
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Han Xu
- Key Laboratory of State Forestry Administration on Tropical Forestry Research, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Runguo Zang
- Key Laboratory of Forest Ecology and Environment of State Forestry Administration, Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing, China
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Yi Ding
- Key Laboratory of Forest Ecology and Environment of State Forestry Administration, Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing, China
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Yide Li
- Key Laboratory of State Forestry Administration on Tropical Forestry Research, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Mingxian Lin
- Key Laboratory of State Forestry Administration on Tropical Forestry Research, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Jinsong Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Cancan Zhang
- 2011 Collaborative Innovation Center of Jiangxi Typical Trees Cultivation and Utilization, Jiulianshan National Observation and Research Station of Chinese Forest Ecosystem, College of Forestry, Jiangxi Agricultural University, Nanchang, China
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11
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Bu W, Li Y. Abstract P5-07-04: Transition from a pre-malignant lesion to cancer does not require stemness of the cancer-originating cells in the lesion. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-p5-07-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The precancerous lesion is the final step before malignancy, and is thus a key step to cancer prevention. Precancerous lesions are heterogeneous harboring distinct subsets of cells from stem cells to differentiated cells. Whether the stem cells or other subsets in these precancerous lesions are responsible for the eventual cancer remains unanswered. Here, we report that in the precancerous lesions of the MMTV-Wnt1 model of basal-like breast cancer, there exist the stem cell-enriched keratin 6a+ subset and more differentiated WAP+ cell subset. We demonstrate that both mutated Ras and B-Raf can robustly transform both cell subsets into cancer. These data suggest that multiple cell subsets in precancerous early lesions can evolve into cancer. This finding indicates that cancer prevention should target both self-renewing cells and other cell subsets in developing precancerous lesions in high-risk individuals.
Citation Format: Bu W, Li Y. Transition from a pre-malignant lesion to cancer does not require stemness of the cancer-originating cells in the lesion [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-07-04.
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Affiliation(s)
- W Bu
- Baylor College of Medicine, Houston, TX
| | - Y Li
- Baylor College of Medicine, Houston, TX
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12
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Johnston A, Garcia S, Hein S, Bu W, Yi L. Abstract P2-07-08: Neuroleptics in breast cancer risk. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-p2-07-08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
This abstract was not presented at the symposium.
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Affiliation(s)
| | - S Garcia
- Baylor College of Medicine, Houston, TX
| | - S Hein
- Baylor College of Medicine, Houston, TX
| | - W Bu
- Baylor College of Medicine, Houston, TX
| | - L Yi
- Baylor College of Medicine, Houston, TX
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13
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Wang J, Wu L, Zhang C, Zhao X, Bu W, Gadow KV. Combined effects of nitrogen addition and organic matter manipulation on soil respiration in a Chinese pine forest. Environ Sci Pollut Res Int 2016; 23:22701-22710. [PMID: 27557973 DOI: 10.1007/s11356-016-7474-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 08/15/2016] [Indexed: 06/06/2023]
Abstract
The response of soil respiration (Rs) to nitrogen (N) addition is one of the uncertainties in modelling ecosystem carbon (C). We reported on a long-term nitrogen (N) addition experiment using urea (CO(NH2)2) fertilizer in which Rs was continuously measured after N addition during the growing season in a Chinese pine forest. Four levels of N addition, i.e. no added N (N0: 0 g N m-2 year-1), low-N (N1: 5 g N m-2 year-1), medium-N (N2: 10 g N m-2 year-1), and high-N (N3: 15 g N m-2 year-1), and three organic matter treatments, i.e. both aboveground litter and belowground root removal (LRE), only aboveground litter removal (LE), and intact soil (CK), were examined. The Rs was measured continuously for 3 days following each N addition application and was measured approximately 3-5 times during the rest of each month from July to October 2012. N addition inhibited microbial heterotrophic respiration by suppressing soil microbial biomass, but stimulated root respiration and CO2 release from litter decomposition by increasing either root biomass or microbial biomass. When litter and/or root were removed, the "priming" effect of N addition on the Rs disappeared more quickly than intact soil. This is likely to provide a point of view for why Rs varies so much in response to exogenous N and also has implications for future determination of sampling interval of Rs measurement.
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Affiliation(s)
- Jinsong Wang
- Key Laboratory for Forest Resources and Ecosystem Processes, Beijing Forestry University, Beijing, 100083, China
- Synthesis Research Center of Chinese Ecosystem Research Network, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - L Wu
- Sustainable Soils and Grassland Systems, Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - Chunyu Zhang
- Key Laboratory for Forest Resources and Ecosystem Processes, Beijing Forestry University, Beijing, 100083, China
| | - Xiuhai Zhao
- Key Laboratory for Forest Resources and Ecosystem Processes, Beijing Forestry University, Beijing, 100083, China.
| | - Wensheng Bu
- College of Forestry, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Klaus V Gadow
- Department of Forestry and Wood Technology, University of Stellenbosch, Stellenbosch, South Africa
- Faculty of Forestry and Forest Ecology, Georg-August-University Göttingen, Büsgenweg 5, D-37077, Göttingen, Germany
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14
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Zheng ZY, Bu W, Tian L, Fan C, Gao X, Zhang X, Yu C, Wang H, Liao YH, Li Y, Lewis MT, Edwards D, Zwaka TP, Hilsenbeck SG, Medina D, Perou CM, Creighton CJ, Zhang XH, Chang EC. Abstract P2-06-11: Wild type N-Ras, overexpressed in basal-like breast cancer, promotes tumor formation by inducing IL8 secretion via JAK2 activation. Cancer Res 2016. [DOI: 10.1158/1538-7445.sabcs15-p2-06-11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
"Basal-like" breast cancer (BLBC) is a very aggressive subtype of breast cancer. BLBC has very poor prognosis — median time to distant recurrence is just 2.6 years vs. 5 years overall, and survival time from diagnosis of distant metastatic disease is 9 months vs. 22 months. BLBC tumors usually do not express ER, Her2, or progesterone receptor. As such, they cannot be treated by the current targeted therapies, which target these molecules. What drive the formation and progression of BLBCs is largely unclear.
Ras GTPases are best known for mediating growth factor signaling. Oncogenic mutations in the RAS genes, K-RAS in particular, are found in more than 30% of human tumors. Surprisingly, oncogenic RAS mutations are rare in breast cancer. However, we found that wild-type N-RAS is overexpressed in BLBCs, possibly partly via promoter demethylation, but not in other breast cancer subtypes. Repressing N-RAS inhibits transformation and tumor growth, while overexpressing it enhances these processes even in preinvasive BLBC cells. In contrast, in breast cancer cells of other subtypes, repressing N-RAS expression does not affect growth and transforming activities. We identified N-Ras-responsive genes, most of which encode chemokines and cytokines, e.g., IL8. High expression levels of these N-Ras-responsive genes as well as of N-RAS itself in tumors correlate with poor patient outcome. N-Ras, but not K-Ras, induces IL8 by binding and activating the cytoplasmic pool of JAK2; IL8 then acts on both the cancer cells and stromal fibroblasts.
In conclusion, N-Ras drives BLBC by promoting transformation in epithelial cells, which may in turn remodel the tumor microenvironment to create a proinvasive state. Although oncogenic mutations affecting RAS are common in many other human cancers, tumorigenesis in an important subset of breast cancers is driven instead by increasing activity of wild-type N-Ras. Thus, to fully assess the impact of Ras on tumorigenesis, the role of wild-type as well as mutant Ras proteins must be carefully examined.
Citation Format: Zheng Z-Y, Bu W, Tian L, Fan C, Gao X, Zhang X, Yu C, Wang H, Liao Y-H, Li Y, Lewis MT, Edwards D, Zwaka TP, Hilsenbeck SG, Medina D, Perou CM, Creighton CJ, Zhang XH, Chang EC. Wild type N-Ras, overexpressed in basal-like breast cancer, promotes tumor formation by inducing IL8 secretion via JAK2 activation. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-06-11.
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Affiliation(s)
- Z-Y Zheng
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - W Bu
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - L Tian
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - C Fan
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - X Gao
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - X Zhang
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - C Yu
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - H Wang
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - Y-H Liao
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - Y Li
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - MT Lewis
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - D Edwards
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - TP Zwaka
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - SG Hilsenbeck
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - D Medina
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - CM Perou
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - CJ Creighton
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - XH Zhang
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
| | - EC Chang
- Baylor College of Medicine; University of North Carolina-Chapel Hill; National Taiwan University Hospital
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15
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Hein SM, Haricharan S, Johnston AN, Toneff MJ, Reddy JP, Dong J, Bu W, Li Y. Luminal epithelial cells within the mammary gland can produce basal cells upon oncogenic stress. Oncogene 2015; 35:1461-7. [PMID: 26096929 PMCID: PMC4688047 DOI: 10.1038/onc.2015.206] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [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: 10/02/2014] [Revised: 05/04/2015] [Accepted: 05/04/2015] [Indexed: 01/05/2023]
Abstract
In the normal mammary gland, the basal epithelium is known to be bipotent and can generate either basal or luminal cells, whereas the luminal epithelium has not been demonstrated to contribute to the basal compartment in an intact and normally developed mammary gland. It is not clear whether cellular heterogeneity within a breast tumor results from transformation of bipotent basal cells or from transformation and subsequent basal conversion of the more differentiated luminal cells. Here we used a retroviral vector to express an oncogene specifically in a small number of the mammary luminal epithelial cells and tested their potential to produce basal cells during tumorigenesis. This in-vivo lineage-tracing work demonstrates that luminal cells are capable of producing basal cells on activation of either polyoma middle T antigen or ErbB2 signaling. These findings reveal the plasticity of the luminal compartment during tumorigenesis and provide an explanation for cellular heterogeneity within a cancer.
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Affiliation(s)
- S M Hein
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.,Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA
| | - S Haricharan
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA
| | - A N Johnston
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA
| | - M J Toneff
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - J P Reddy
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - J Dong
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.,Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA
| | - W Bu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.,Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA
| | - Y Li
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.,Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA
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16
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Xiao Q, Bu W, Ren Y, Qiu J, Xiangpeng Z. PO-1079 Single W18O49 nanowire: a multifunctional nanoplatform for image-guided dose-enhancement radiation therapy. Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)41071-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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Chen F, Bu W, Cai W, Shi J. Functionalized upconversion nanoparticles: versatile nanoplatforms for translational research. Curr Mol Med 2014; 13:1613-32. [PMID: 24206131 DOI: 10.2174/1566524013666131111122133] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 05/17/2012] [Accepted: 09/10/2013] [Indexed: 11/22/2022]
Abstract
The design, application, and translation of targeted multimodality molecular imaging probes based on nanotechnology have attracted increasing attentions during the last decade and will continue to play vital roles in cancer diagnosis and personalized medicine. With the growing awareness of drawbacks of traditional organic dyes and quantum dots, biocompatible lanthanide ion doped upconversion nanoparticles have emerged as promising candidates for clinically translatable imaging probes, owing to their unique features that are suitable for future targeted multimodal imaging in living subjects. In this review, we summarized the recent advances in the field of functionalized upconversion nanoparticles (f-UCNP) for biological imaging and therapy in vivo, and discussed the future research directions, obstacles ahead, and the potential use of f-UCNP in translational research.
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Affiliation(s)
- F Chen
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, People's Republic of China.
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18
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Bu W, Zang R, Ding Y. Field observed relationships between biodiversity and ecosystem functioning during secondary succession in a tropical lowland rainforest. Acta Oecologica 2014. [DOI: 10.1016/j.actao.2013.10.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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19
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Zhang Y, Li H, Xu Z, Bu W, Liu C, Dong JY, Hu Y. Synthesis of low dispersity star-like polyethylene: a combination of click chemistry and a sol–gel process. Polym Chem 2014. [DOI: 10.1039/c4py00063c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Low dispersity star-like polyethylene was synthesized via a facile sol–gel process using trimethoxysilane-terminated polyethylene derived from thiol-ene click chemistry.
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Affiliation(s)
- Yongjie Zhang
- Beijing National Laboratory for Molecular Sciences
- CAS Key Laboratory of Engineering Plastics
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P.R. China
| | - Huayi Li
- Beijing National Laboratory for Molecular Sciences
- CAS Key Laboratory of Engineering Plastics
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P.R. China
| | - Zenan Xu
- Beijing National Laboratory for Molecular Sciences
- CAS Key Laboratory of Engineering Plastics
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P.R. China
| | - Wensheng Bu
- Beijing National Laboratory for Molecular Sciences
- CAS Key Laboratory of Engineering Plastics
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P.R. China
| | - Chenyang Liu
- Beijing National Laboratory for Molecular Sciences
- CAS Key Laboratory of Engineering Plastics
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P.R. China
| | - Jin-Yong Dong
- Beijing National Laboratory for Molecular Sciences
- CAS Key Laboratory of Engineering Plastics
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P.R. China
| | - Youliang Hu
- Beijing National Laboratory for Molecular Sciences
- CAS Key Laboratory of Engineering Plastics
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P.R. China
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20
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Abstract
Abstract
Melt blending, extrusion and drawing of polycarbonate (PC) blends containing a thermotropic liquid crystalline polymer (LCP) are reported for a copolyester PCDT synthesised in this laboratory. A single screw extruder is used at four temperatures. The rheology of the PCDT/PC blend, PCDT and PC was measured by means of a capillary rheometer at these temperatures. The morphology of extruded and subsequently drawn strands was studied with the help of a scanning electron microscope and analysed. In PCDT/PC extruded strands, the morphology of the PCDT dispersed phase, changes from spherical through ellipsoidal to elongated with decreasing processing temperature. In contrast to this, in drawn strands with a draw ratio of 10, the morphology of the PCDT changes from ellipsoidal through elongated to fibrillar with increasing processing temperature. It is believed that the relative viscosity of the two phases is the decisive factor determining the microstructure formation of polymer blends containing thermotropic liquid crystalline polymers. Fibril formation is related to the deformation and coalescence of PCDT melt droplets by the drawing at higher temperatures.
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Affiliation(s)
- J. He
- State Key Laboratory of Engineering Plastics, Institute of Chemistry, Academia Sinica, Beijing, China
| | - W. Bu
- State Key Laboratory of Engineering Plastics, Institute of Chemistry, Academia Sinica, Beijing, China
| | - H. Zhang
- State Key Laboratory of Engineering Plastics, Institute of Chemistry, Academia Sinica, Beijing, China
| | - P. Xie
- State Key Laboratory of Engineering Plastics, Institute of Chemistry, Academia Sinica, Beijing, China
| | - X. Xu
- Beijing Research Institute of Chemical Industry, Ministry of Chemical Industry, Beijing, China
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21
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Bu W, Liang D, Liu R, Loll P, Dmochowski I, Eckenhoff R. Interaction of saturated fatty acids with apoferritin. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311079244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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22
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Pittler J, Bu W, Vaknin D, Travesset A, McGillivray DJ, Lösche M. Charge inversion at minute electrolyte concentrations. Phys Rev Lett 2006; 97:046102. [PMID: 16907594 DOI: 10.1103/physrevlett.97.046102] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Indexed: 05/11/2023]
Abstract
Anionic dimyristoylphosphatidic acid monolayers spread on LaCl3 solutions reveal strong cation adsorption and a sharp transition to surface overcharging at unexpectedly low bulk salt concentrations. We determine the surface accumulation of La3+ with anomalous x-ray reflectivity and find that La3+ compensates the lipid surface charge by forming a Stern layer with approximately 1 La3+ ion per 3 lipids below a critical bulk concentration, ct approximately 500 nM. Above ct, the surface concentration of La3+ increases to a saturation level with approximately 1 La3+ per lipid, thus implying that the total electric charge of the La3+ exceeds the surface charge. This overcharge is observed at approximately 4 orders of magnitude lower concentration than predicted in ion-ion correlation theories. We suggest that transverse electrostatic correlations between mobile ions and surface charges (interfacial Bjerrum pairing) may contribute to the charge inversion.
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Affiliation(s)
- J Pittler
- Institute of Experimental Physics I, University of Leipzig, D-04103 Leipzig, Germany
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23
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Abstract
The EB1 family proteins are highly conserved microtubule-associated proteins. The EB1 protein in yeast has been shown to play an important role in regulating microtubule dynamics and chromosome segregation. Human EB1 family proteins include EB1, RP1 and EBF3. Although EB1 and RP1 have been shown to associate with microtubules, the subcellular localization of endogenous EBF3 had not been characterized. The function of human EB1 family proteins was also not clear. We therefore investigated the cellular localization of EBF3 and the regulation of microtubule organization by EB1 family proteins. As do EB1 and RP1, EBF3 was found to colocalize with microtubules, preferentially at their plus ends, throughout the cell cycle. Moreover, there was a very strong EBF3 signal at the centrosome in interphase cells and at the spindle poles in mitotic cells. When EB1 family proteins were overexpressed, they associated with the entire microtubule cytoskeleton. In addition, EB1 and EBF3 induced microtubule bundling in some cells overexpressing these proteins. These microtubule bundles were more resistant to nocodazole and were more acetylated than regular microtubules. Our results demonstrate for the first time that human EB1 family proteins could regulate microtubule assembly and stability.
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Affiliation(s)
- W Bu
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas, TX 77030, USA
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24
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Bu W, Sun JL, Yang XC. [Cloning, sequence analysis and high-level expression in Escherichia coli and activity assay of pac-1 gene from Schizosaccharmyces pombe]. Sheng Wu Gong Cheng Xue Bao 2001; 17:203-6. [PMID: 11411232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
The Schizosaccharmyces pombe pac-1 gene product is a kind of dsRNA dependent ribonuclease, which has potential to degrade the dsRNA viral genome, the replication form of ssRNA viral genome and viroid genome. Therefore, to introduce the pac-1 gene into plants conferring them resistance to viruses is a new method of establishing the anti-virus transgenic plant. The pac-1 gene from the S. pmobe genome DNA isolated from China was cloned by means of PCR amplification. The pac-1 gene was inserted into the cloning vector pGEM-7Zf(+) by using restriction endonuclease Kpn I/BamHI. Sequencing analysis shows that it is a complete gene with 1095 necleotides. Compared to the reported pac-1 gene, its homology is significant, but with 5 nucleotides differences, leading to only one amino acid difference. Pac-1 gene was inserted into the prodaryotic expression vector pET-21(a) by using the restriction endonuclase Nde I/BamHI. It was induced by the IPTG in E. coli BL21 harbouring the recombinant vector pET-pac-1. The pac-1 gene product is analyzed by the SDS-PAGE. The result shows the product of pac-1 gene exists in the supernatant part as soluble form and in the precipitant part as inclusion bodies after the cells were lysed by ultrasonic wave. The supernatant was applied to detect the enzyme activity of pac-1 gene product. We concluded that pac-1 gene has the biological activity of degrading the CMV-dsRNA.
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Affiliation(s)
- W Bu
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, China
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25
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Affiliation(s)
- Wensheng Bu
- State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
| | - Yuying Li
- State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
| | - Jiasong He
- State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
| | - Jijun Zeng
- State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
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26
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Bu W, Ye L, Xu Q, Bu X, Yang G, Fan Y. Bis(μ-azido-κ N1:κ N1)bis{[2-(1,5-diazacyclooct-1-yl-κ 2N, N'-methyl)phenolato-κ O]copper(II)}. Acta Crystallogr C 1999. [DOI: 10.1107/s0108270199099515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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27
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Bu W, Ye L, Zhu H, Yang G, Fan Y, Tang W. μ-1,3-Imidazolyl-κ N:κ N'-bis[(diethylenetriaminato-κ 3N)copper] triperchlorate hydrate. Acta Crystallogr C 1999. [DOI: 10.1107/s0108270199099527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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28
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29
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Qin LX, Tang ZY, Li XM, Bu W, Xia JL. Effect of antiangiogenic agents on experimental animal models of hepatocellular carcinoma. Ann Acad Med Singap 1999; 28:147-51. [PMID: 10374041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
A new therapeutic strategy for treating metastasis in hepatocellular carcinoma (HCC) has entailed the use of antiangiogenic agents such as suramin, BB-94 (Batimastat), TNP-470, and carboxyamido-triazole (CAI, a synthetic inhibitor of non-excitable calcium channels that reversibly inhibits angiogenesis). These agents have been used to treat metastatic model of HCC in nude mouse (LCI-D20 mouse model). The results of these studies are summarized in this paper with emphasis on the inhibitory effects of the drugs on tumour growth, angiogenesis, invasion and metastasis in LCI-D20 mouse models. The results suggest that all of the agents used can significantly inhibit tumour growth, angiogenesis, invasion and metastasis of human HCC in nude mouse models, and may be candidates for the control of recurrence and metastasis after HCC resection.
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Affiliation(s)
- L X Qin
- Liver Cancer Institute, Zhongshan Hospital, Shanghai Medical University, PR China
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30
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Bu W, Tang ZY, Sun FX, Ye SL, Liu KD, Xue Q, Chen J, Gao DM. Effects of matrix metalloproteinase inhibitor BB-94 on liver cancer growth and metastasis in a patient-like orthotopic model LCI-D20. Hepatogastroenterology 1998; 45:1056-61. [PMID: 9756006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND/AIMS The aim of this study was to try to understand the effects of the synthetic matrix metalloproteinase inhibitor Batimastat (BB-94) on hepatocellular carcinoma (HCC). METHODOLOGY An orthotopic metastatic human hepatocellular carcinoma in nude mice model (LCI-D20) was used to study primary tumor growth, local invasion and metastasis of HCC. MTT assay was used to study the effects of BB-94 on cytotoxin and proliferation of HCC cell line SMMC-7721 in vitro. A gelatine zymograph was used to study the expression of MMPs in the LCI-D20 tumor tissue. RESULTS BB-94 can inhibit primary tumor growth, local invasion, intrahepatic and lung metastasis, as well as prolong survival. BB-94 did not affect the proliferation of HCC cells in vitro. LCI-D20 tumor tissue expresses MMP-2 and MMP-9. CONCLUSIONS BB-94 has a cytostatic therapeutic effect on HCC.
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Affiliation(s)
- W Bu
- Liver Cancer Institute, Zhongshan Hospital, Shanghai Medical University, PR China
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Bu W, Huang X, Tang Z. [The role of MMP-2 in the invasion and metastasis of hepatocellular carcinoma (HCC)]. Zhonghua Yi Xue Za Zhi 1997; 77:661-4. [PMID: 9772533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
OBJECTIVES To get insights into the role of MMP-2 in the invasion and metastasis of hepatocellular carcinoma (HCC), and to find a method to judge the invasion and metastasis of HCC through MMP-2. METHODS Zymograph and immunohistochemistry were used to study the content and types of positive cells of MMP-2 in the HCC, and statistical methods were used to analyse the association between the content of MMP-2 and the pathological indexes of HCC. RESULTS MMP-2 was expressed by all the normal liver, HCC and surrounding liver parenchyma. The increase of MMP-2 and the presence of the active type of MMP-2 were related to the invasion and metastasis of HCC. The content of MMP-2 in HCC being higher than that in surrounding liver parenchyma was an important index to judge the invasion and metastasis of the HCC. The positive cells of MMP-2 found in immunohistochemistry were normal hepatocytes, cholangioepithelial cells, Ito cells, regenerated hepatocytes, new generated cholangioepithelial cells, and HCC cells. CONCLUSION MMP-2 was related to the invasion and me astasis of HCC. The content of MMP-2 in HCC being higher than that in surrounding liver parenchyma could be bused as an important index to judge the invasion and metastasis of HCC.
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Affiliation(s)
- W Bu
- Liver Cancer Institute and Zhongshan Hospital, Shanghai Medical University
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Xu Y, Bu W, Li B. Metabolic factors capable of inducing Agrobacterium vir gene expression are present in rice (Oryza sativa L.). Plant Cell Rep 1993; 12:160-164. [PMID: 24196854 DOI: 10.1007/bf00239098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/1992] [Revised: 09/11/1992] [Indexed: 06/02/2023]
Abstract
The effects of exudates and extracts from suspension cultures or various parts of rice (Oryza sativa L.) plants on induction of vir (virulence) gene expression in Agrobacterium tumefaciens were examined. Only leaf extracts from panicle-differentiating plants to flowering plants were able to strongly induce activation and expression of vir genes. This induction was similar to that observed with 2 μM acetosyringone (AS), yet there was no synergy between AS and rice extracts. Responses to vir-inducing metabolites and signal molecules were different among various vir loci. These results demonstrate that one or more inducing factors for vir gene expression are also present in rice, but only in specific parts and developmental stages.
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Affiliation(s)
- Y Xu
- Biotechnology Research Center, Zhongshan University, 510275, Guanzhou, China
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