| 1. |
- Chen, Jialin, et al.
(author)
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Hydroxycamptothecin and substratum stiffness synergistically regulate fibrosis of human corneal fibroblasts
- 2023
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In: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 9:2, s. 959-967
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Journal article (peer-reviewed)abstract
- Corneal fibrosis is a common outcome of inappropriate repair associated with trauma or ocular infection. Altered biomechanical properties with increased corneal stiffness is a feature of fibrosis that cause corneal opacities, resulting in severe visual impairment and even blindness. The present study aims to determine the effect of hydroxycamptothecin (HCPT) and matrix stiffness on transforming growth factor-β1 (TGF-β1)-induced fibrotic processes in human corneal fibroblasts (HTK cells). HTK cells were cultured on substrates with different stiffnesses ("soft", ∼261 kPa; "stiff", ∼2.5 × 103 kPa) and on tissue culture plastic (TCP, ∼106 kPa) and simultaneously treated with or without 1 μg/mL HCPT and 10 ng/mL TGF-β1. We found that HCPT induced decreased cell viability and antiproliferative effects on HTK cells. TGF-β1-induced expression of fibrosis-related genes (FN1, ACTA2) was reduced if the cells were simultaneously treated with HCPT. Substrate stiffness did not affect the expression of fibrosis-related genes. The TGF-β1 induced expression of FN1 on both soft and stiff substrates was reduced if cells were simultaneously treated with HCPT. However, this trend was not seen for ACTA2, i.e., the TGF-β1 induced expression of ACTA2 was not reduced by simultaneous treatment of HCPT in either soft or stiff substrate. Instead, HCPT treatment in the presence of TGF-β1 resulted in increased gene expression of keratocyte phenotype makers (LUM, KERA, AQP1, CHTS6) on both substrate stiffnesses. In addition, the protein expression of keratocyte phenotype makers LUM and ALDH3 was increased in HTK cells simultaneously treated with TGF-β1 and HCPT on stiff substrate as compared to control, i.e., without HCPT. In conclusion, we found that HCPT can reduce TGF-β1-induced fibrosis and promote the keratocyte phenotype in a substrate stiffness dependent manner. Thus, HCPT stimulation might be an approach to stimulate keratocytes in the appropriate healing stage to avoid or reverse fibrosis and achieve more optimal corneal wound healing.
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| 2. |
- Chen, Zhixuan, et al.
(author)
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Effects of Zinc, Magnesium, and Iron Ions on Bone Tissue Engineering
- 2022
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In: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 8:6, s. 2321-2335
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Research review (peer-reviewed)abstract
- Large-sized bone defects are a great challenge in clinics and considerably impair the quality of patients' daily life. Tissue engineering strategies using cells, scaffolds, and bioactive molecules to regulate the microenvironment in bone regeneration is a promising approach. Zinc, magnesium, and iron ions are natural elements in bone tissue and participate in many physiological processes of bone metabolism and therefore have great potential for bone tissue engineering and regeneration. In this review, we performed a systematic analysis on the effects of zinc, magnesium, and iron ions in bone tissue engineering. We focus on the role of these ions in properties of scaffolds (mechanical strength, degradation, osteogenesis, antibacterial properties, etc.). We hope that our summary of the current research achievements and our notifications of potential strategies to improve the effects of zinc, magnesium, and iron ions in scaffolds for bone repair and regeneration will find new inspiration and breakthroughs to inspire future research.
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| 3. |
- Chi, Jiayu, et al.
(author)
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Topographic Orientation of Scaffolds for Tissue Regeneration : Recent Advances in Biomaterial Design and Applications
- 2022
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In: Biomimetics. - : MDPI. - 2313-7673. ; 7:3
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Research review (peer-reviewed)abstract
- Tissue engineering to develop alternatives for the maintenance, restoration, or enhancement of injured tissues and organs is gaining more and more attention. In tissue engineering, the scaffold used is one of the most critical elements. Its characteristics are expected to mimic the native extracellular matrix and its unique topographical structures. Recently, the topographies of scaffolds have received increasing attention, not least because different topographies, such as aligned and random, have different repair effects on various tissues. In this review, we have focused on various technologies (electrospinning, directional freeze-drying, magnetic freeze-casting, etching, and 3-D printing) to fabricate scaffolds with different topographic orientations, as well as discussed the physicochemical (mechanical properties, porosity, hydrophilicity, and degradation) and biological properties (morphology, distribution, adhesion, proliferation, and migration) of different topographies. Subsequently, we have compiled the effect of scaffold orientation on the regeneration of vessels, skin, neural tissue, bone, articular cartilage, ligaments, tendons, cardiac tissue, corneas, skeletal muscle, and smooth muscle. The compiled information in this review will facilitate the future development of optimal topographical scaffolds for the regeneration of certain tissues. In the majority of tissues, aligned scaffolds are more suitable than random scaffolds for tissue repair and regeneration. The underlying mechanism explaining the various effects of aligned and random orientation might be the differences in “contact guidance”, which stimulate certain biological responses in cells.
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| 4. |
- Sheng, Renwang, et al.
(author)
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Material stiffness in cooperation with macrophage paracrine signals determines the tenogenic differentiation of mesenchymal stem cells
- 2023
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In: Advanced Science. - : John Wiley & Sons. - 2198-3844. ; 10:17
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Journal article (peer-reviewed)abstract
- Stiffness is an important physical property of biomaterials that determines stem cell fate. Guiding stem cell differentiation via stiffness modulation has been considered in tissue engineering. However, the mechanism by which material stiffness regulates stem cell differentiation into the tendon lineage remains controversial. Increasing evidence demonstrates that immune cells interact with implanted biomaterials and regulate stem cell behaviors via paracrine signaling; however, the role of this mechanism in tendon differentiation is not clear. In this study, polydimethylsiloxane (PDMS) substrates with different stiffnesses are developed, and the tenogenic differentiation of mesenchymal stem cells (MSCs) exposed to different stiffnesses and macrophage paracrine signals is investigated. The results reveal that lower stiffnesses facilitates tenogenic differentiation of MSCs, while macrophage paracrine signals at these stiffnesses suppress the differentiation. When exposed to these two stimuli, MSCs still exhibit enhanced tendon differentiation, which is further elucidated by global proteomic analysis. Following subcutaneous implantation in rats for 2 weeks, soft biomaterial induces only low inflammation and promotes tendon-like tissue formation. In conclusion, the study demonstrates that soft, rather than stiff, material has a greater potential to guide tenogenic differentiation of stem cells, which provides comprehensive evidence for optimized bioactive scaffold design in tendon tissue engineering.
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| 5. |
- Liu, Weihua, et al.
(author)
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The impact of digital supply chain announcements disclosing corporate social responsibility information on stock market value
- 2023
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In: Industrial management & data systems. - : EMERALD GROUP PUBLISHING LTD. - 0263-5577 .- 1758-5783.
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Journal article (peer-reviewed)abstract
- PurposeUsing social network theory (SNT), this study empirically examines the impact of digital supply chain announcements disclosing corporate social responsibility (CSR) information on stock market value.Design/methodology/approachBased on 172 digital supply chain announcements disclosing CSR information from Chinese A-share listed companies, this study uses event study method to test the hypotheses.FindingsFirst, digital supply chain announcements disclosing CSR information generate positive and significant market reactions, which is timely. Second, strategic CSR and value-based CSR disclosed in digital supply chain announcements have a more positive impact on stock market, however there is no significant difference when the CSR orientation is either towards internal or external stakeholders. Third, in terms of digital supply chain network characteristics, announcements reflecting higher relationship embeddedness and higher digital breadth and depth lead to more positive increases of stock value.Originality/valueFirst, the authors consider the value of CSR information in digital supply chain announcements, using an event study approach to fill the gap in the related area. This study is the first examination of the joint impact of digital supply chain and CSR on market reactions. Second, compared to the previous studies on the single dimension of digital supply chain technology application, the authors innovatively consider supply chain network relationship and network structure based on social network theory and integrate several factors that may affect the market reaction. This study improves the understanding of the mechanism between digital supply chain announcements disclosing CSR information and stock market, and informs future research.
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| 6. |
- Ren, Weixi, et al.
(author)
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An intelligent optimization method for the facility environment on rural roads
- 2024
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In: Computer-Aided Civil and Infrastructure Engineering. - 1093-9687 .- 1467-8667. ; In Press
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Journal article (peer-reviewed)abstract
- This study develops an intelligent optimization method of the facility environment (i.e., road facilities and surrounding landscapes) from drivers’ visual perception to adjust operation speeds on rural roads. Different from previous methods that heavily rely on expert experience and are time-consuming, this method can rapidly generate optimized visual images of the facility environment and promptly verify the optimization effects. In this study, a visual road schema model is established to quantify the facility environment from drivers’ visual perception, and an automated optimization scheme determination approach considering the original facility environment characteristics is proposed using self-explaining theory. Then, Cycle-consistent generative adversarial network is used to automatically generate optimized facility environment images. To verify the optimization effect, operation speeds of the optimized facility environments are predicted using random forest. The case study shows that this method can effectively optimize the facility environment where original operation speeds are more than 20% over the speed limits, and the whole process only takes 1 h far less than several months or years in previous ways. Overall, this study advances the intelligence level in optimizing the facility environment and enhances rural road safety.
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