Synthesis and Antiplatelet Adhesion Behavior of a Poly(L-lactide-co-glycolide)–Poly(1,5-dioxepan-2-one) Multiblock Copolymer

AbstractAtherosclerosis is a long-term disease process of the vascular system that is characterized by the formation of atherosclerotic plaques, which are inflammatory regions on medium and large-sized arteries. There are many factors contributing to plaque formation, such as changes in shear stress levels, rupture of endothelial cells, accumulation of lipids, and recruitment of leukocytes. Shear stress is one of the main factors that regulates the homeostasis of the circulatory system; therefore, sudden and chronic changes in shear stress may cause severe pathological conditions. In this study, microfluidic channels with cavitations were designed to mimic the shape of the atherosclerotic blood vessel, where the shear stress and pressure difference depend on design of the microchannels. Changes in the inflammatory-related molecules ICAM-1 and IL-8 were investigated in THP-1 cells in response to applied shear stresses in an continuous cycling system through microfluidic channels with periodic cavitations. ICAM-1 mRNA expression and IL-8 release were analyzed by qRT-PCR and ELISA, respectively. Additionally, the adhesion behavior of sheared THP-1 cells to endothelial cells was examined by fluorescence microscopy. The results showed that 15 Pa shear stress significantly increases expression of ICAM-1 gene and IL-8 release in THP-1 cells, whereas it decreases the adhesion between THP-1 cells and endothelial cells.

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Superior Alignment of Human iPSC-Osteoblasts Associated with Focal Adhesion Formation Stimulated by Oriented Collagen Scaffold

International Journal of Molecular Sciences ◽

10.3390/ijms22126232 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6232

Author(s):

Ryosuke Ozasa ◽

Aira Matsugaki ◽

Tadaaki Matsuzaka ◽

Takuya Ishimoto ◽

Hui-Suk Yun ◽

...

Keyword(s):

Bone Tissue ◽

Structural Organization ◽

Critical Role ◽

Bone Matrix ◽

Adhesion Formation ◽

Focal Adhesions ◽

Collagen Scaffold ◽

Patient Specific ◽

Specific Cell ◽

Adhesion Behavior

Human-induced pluripotent stem cells (hiPSCs) can be applied in patient-specific cell therapy to regenerate lost tissue or organ function. Anisotropic control of the structural organization in the newly generated bone matrix is pivotal for functional reconstruction during bone tissue regeneration. Recently, we revealed that hiPSC-derived osteoblasts (hiPSC-Obs) exhibit preferential alignment and organize in highly ordered bone matrices along a bone-mimetic collagen scaffold, indicating their critical role in regulating the unidirectional cellular arrangement, as well as the structural organization of regenerated bone tissue. However, it remains unclear how hiPSCs exhibit the cell properties required for oriented tissue construction. The present study aimed to characterize the properties of hiPSCs-Obs and those of their focal adhesions (FAs), which mediate the structural relationship between cells and the matrix. Our in vitro anisotropic cell culture system revealed the superior adhesion behavior of hiPSC-Obs, which exhibited accelerated cell proliferation and better cell alignment along the collagen axis compared to normal human osteoblasts. Notably, the oriented collagen scaffold stimulated FA formation along the scaffold collagen orientation. This is the first report of the superior cell adhesion behavior of hiPSC-Obs associated with the promotion of FA assembly along an anisotropic scaffold. These findings suggest a promising role for hiPSCs in enabling anisotropic bone microstructural regeneration.

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Effects of Pre- and Post-Carburizing Surface Modification on the Tribological and Adhesion Properties of Heat-Resistant KHR 45A Steel for Cracking Tubes

Materials ◽

10.3390/ma14133658 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3658

Author(s):

Auezhan Amanov ◽

Joo-Hyun Choi ◽

Young-Sik Pyun

Keyword(s):

Surface Modification ◽

Surface Treatment ◽

Steel Substrate ◽

Heat Exposure ◽

Scratch Resistance ◽

Adhesion Properties ◽

Heat Resistant ◽

Adhesion Behavior ◽

Steel Substrates ◽

Carburizing Process

In this study, the effects of ultrasonic nanocrystal surface modification (UNSM) technology on the tribological properties and scratch-induced adhesion behavior of a heat-resistant KHR 45A steel cracking tube, which is used for the pyrolysis process, were investigated. The main objective of this study is to investigate the effects of pre- and post-carburizing UNSM treatment on the tribological and adhesion performances of carburized domestic KHR 45A (A) steel and to compare the results with the existing carburized Kubota-made KHR 45A steel (B). A carburizing process was carried out on the polished and UNSM-treated KHR 45A steel substrates, which were cut out from the cracking tube, at 300 °C heat exposure for 300 h. The thickness of the carburizing layer was about 10 μm. UNSM technology was applied as pre- and post-carburizing surface treatment; both reduced the friction coefficient and wear rate compared to that of the carburized KHR 45A steel substrate. It was also found that the application of UNSM technology increased the critical load, which implies the improvement of adhesion behavior between the carburizing layer and the KHR steel substrate. The application of UNSM technology as pre- and post-carburizing surface treatment could help replace carburized Kubota-made KHR 45A steel (B) thanks to the improved tribological performance, enhanced scratch resistance, load bearing capacity, and adhesion of domestic KHR 45A (A) steel.

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Biodegradable all polyester-based multiblock copolymer elastomers with controlled properties

Polymer Chemistry ◽

10.1039/d1py00076d ◽

2021 ◽

Vol 12 (12) ◽

pp. 1837-1845

Author(s):

Hongjuan Li ◽

Siyuan Xu ◽

Jing Li ◽

Yanyan Tu ◽

Xiaohong Li ◽

...

Keyword(s):

Environmentally Friendly ◽

Thermoplastic Elastomers ◽

Multiblock Copolymer ◽

Tunable Properties ◽

Polymerization Method

A cascade polymerization method is developed here for the synthesis of environmentally-friendly biodegradable all polyester-based thermoplastic elastomers with tunable properties.

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A molecular simulation study on the adhesion behavior of a functionalized polyethylene-functionalized graphene interface

Physical Chemistry Chemical Physics ◽

10.1039/c5cp04699h ◽

2015 ◽

Vol 17 (41) ◽

pp. 27414-27427 ◽

Cited By ~ 18

Author(s):

Sousa Javan Nikkhah ◽

Mohammad Reza Moghbeli ◽

Seyed Majid Hashemianzadeh

Keyword(s):

Molecular Simulation ◽

Simulation Study ◽

Adhesion Energy ◽

Functionalized Graphene ◽

Adhesion Behavior ◽

Interfacial Separation ◽

Graphene Interface

Snapshots and the adhesion energy/interfacial separation plot of PE20OH/G3COOH.

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Improvement of Interfacial Adhesion in PP/PS Blends Enhanced with Polyethylene-Polyamine Surface Treated Carbon Fiber

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1061-1062.170 ◽

2014 ◽

Vol 1061-1062 ◽

pp. 170-174

Author(s):

Jian Li

Keyword(s):

Contact Angle ◽

Carbon Fiber ◽

Photoelectron Spectroscopy ◽

Interfacial Adhesion ◽

Morphological Changes ◽

Water Contact ◽

Polyethylene Polyamine ◽

Adhesion Behavior ◽

Interlaminar Shear ◽

Treated Carbon

The effects of surface treatment of a carbon fiber (CF) by Polyethylene-polyamine (PEPA) on the interfacial adhesion behavior and morphology of polypropylene/polystyrene (PP/PS) matrix blends filled CF composites were investigated. Effects of surface treated a commercial CF on mechanical properties are studied. Contact angle was measured to examine the changes in wettability of the carbon fiber. The chemical and morphological changes were characterized by using X-ray photoelectron spectroscopy (XPS). PP/PS/CF composites were fabricated with and without PEPA treatment, and their interlaminar fracture toughnesses were compared. The results showed that the interlaminar shear strength (ILSS) of composites has been greatly improved filled PEPA modification CF. The water contact angle of resin sample decreased 50% after addition of PEPA surface treated CF.

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