Ningning Wang¹, Caili Zhang^1,2,*, Wenqin Zhu³, Yunxuan Weng^1,2,*

Journal of Renewable Materials, Vol.8, No.9, pp. 1139-1149, 2020, DOI:10.32604/jrm.2020.09961

Abstract To clarify the effects of lignin as a biodegradable filler added into the PLA matrix, PLA/lignin composites with or without silane coupling agent of γ- (2,3-epoxypropoxy)propy trimethoxysilane (KH560) were prepared by a one-step solvent-free modification method. The effects of KH560 as a compatibilizer on the morphology, chemical structure, crystallization behavior, thermal degradative behavior as well as mechanical strength of the PLA/lignin composites were analyzed in detail. It was found that, after modification by KH560, the fractured surfaces of composites became smooth, suggested sufficient bonding between the lignin and PLA in the composites with KH560 coupling agent molecules. This result further… More >

KHAWAR ALI SHAHZAD^1,2,#, ZHONGJIE QIN^3,4,#, YAN LI^1,2,*, DELIN XIA^3,4,*

BIOCELL, Vol.44, No.2, pp. 137-145, 2020, DOI:10.32604/biocell.2020.08500

Abstract Focal adhesions are polyproteins linked to extracellular matrix and cytoskeleton, which play an important role in the process of transforming force signals into intracellular chemical signals and subsequently triggering related physiological or pathological reactions. The cytoskeleton is a network of protein fibers in the cytoplasm, which is composed of microfilaments, microtubules, intermediate filaments, and cross-linked proteins. It is a very important structure for cells to maintain their basic morphology. This review summarizes the process of fluid shear stress transduction mediated by focal adhesion and the key role of the cytoskeleton in this process, which focuses on the focal adhesion and… More >

Xiaodong Wang^1,2, Meng Su², Chuntai Liu², Changyu Shen², Xianhu Liu^2,*

Journal of Renewable Materials, Vol.8, No.1, pp. 89-99, 2020, DOI:10.32604/jrm.2020.08493

Abstract Poly (vinyl alcohol) (PVA)/reduced graphene oxide (rGO) nanocomposites is prepared by the immersion of PVA/graphene oxide (GO) nanocomposites in the reducing agent aqueous solution. The PVA/graphene nanocomposites can be used as scaffold after treatment by chemical crosslinking agents. The surface hydrophilicity of the nanocomposite scaffolds decreased with the addition of GO or rGO by measuring the contact angles of scaffolds. The electrical conductivity of PVA/rGO nanocomposite scaffold increased with rGO content increased. The highest conductivity of PVA/rGO nanocomposite scaffolds with 10 wt% rGO could reach to 12.16 × 10⁻³ S/m. The NIH-3T3 fibroblasts attach and grow well on the surface… More >

GRACIELA CRISTINA CALABRESE*, ROSA WAINSTOK**

BIOCELL, Vol.28, No.3, pp. 251-258, 2004, DOI:10.32604/biocell.2004.28.251

Abstract Endothelial cells, at the cell-cell borders, express PECAM-1, and have been implicated in vascular functions. The monoclonal antibody MEC 13.3 recognizes PECAM-1 molecule from mouse vessels and allows to analyze the ontogeny of mouse endothelium. At the present, little is known about the molecular basis of differentiation pathways of endothelial cells, that enables its morphological heterogeneity. The purpose of this study was to analyze the pattern of PECAM-1 expression, employing monoclonal antibody MEC 13.3, in cellular suspensions obtained from different mouse organs at pre and postnatal stages.
Fluorescence activated cell sorter analysis showed a different profile of the glycoprotein… More >

T.H. Satoh², T.A. Surmacz³, O. Nyormoi⁴, C.M. Whitacre¹

BIOCELL, Vol.27, No.1, pp. 47-55, 2003, DOI:10.32604/biocell.2003.27.047

Abstract This study shows a strong association between cell attachment to substratum and activation of β1-integrin-signaling with resistance to the camptothecin derivative topotecan (TPT) in breast cancer cells. We propose a mechanistic-driven approach to sensitize the cells to camptothecins. ZR-75-1 anchoragedependent breast cancer cell line, its derivative 9D3S suspension cells (9D3S-S), and 9D3S cells attached to fibronectin-coated plates (9D3S-A) were treated with TPT (1 µM) or CPT-11 (40 µM) for 48 h. Programmed cell death (PCD), as shown by poly(ADP-ribose) polymerase (PARP), pro-caspase-3 and pro-caspase-9 cleavage, was observed in 9D3S-S cells but not in ZR-75-1 or 9D3S-A cells. Because p125 focal… More >

Yunfeng Chen^1,2,3,†,*, Jiexi Liao^4,†, Zhou Yuan¹, Kaitao Li⁴, Baoyu Liu⁴, Lining Arnold Ju^4,5,6, Cheng Zhu^1,2,4,5,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 97-97, 2019, DOI:10.32604/mcb.2019.07123

Abstract Force-mediated molecular binding initiates numerous cellular activities such as cell adhesion, migration, and activation. Dynamic force spectroscopy (DFS) is widely used to examine molecular binding and cell mechano-signaling [1]. The rate of dissociation, off-rate, is an important attribute of molecular binding that reflects bond stability. Extensive DFS works have demonstrated that off-rates are a function of force magnitude, yielding signature bond behaviors like “catch bond” [2]. However, as a controversial topic of the field, different DFS assays, i.e., force-clamp and force-ramp assays, often yielded distinctive "off-rate vs. force" relations from the same molecular system [3]. Such discrepancies cast doubt on… More >

Christopher A. Lemmon^1,2, Nathan J. Sniadecki³, Sami Alom Ruiz^1,3, John L. Tan, Lewis H. Romer^2,4,5, Christopher S. Chen^3,4

Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 1-16, 2005, DOI:10.3970/mcb.2005.002.001

Abstract The interplay of mechanical forces between the extracellular environment and the cytoskeleton drives development, repair, and senescence in many tissues. Quantitative definition of these forces is a vital step in understanding cellular mechanosensing. Microfabricated post array detectors (mPADs) provide direct measurements of cell-generated forces during cell adhesion to extracellular matrix. A new approach to mPAD post labeling, volumetric imaging, and an analysis of post bending mechanics determined that cells apply shear forces and not point moments at the matrix interface. In addition, these forces could be accurately resolved from post deflections by using images of post tops and bases. Image… More >

M.R. Kaazempur Mofrad^1,2, J. Golji², N.A. Abdul Rahim², R.D. Kamm³

Molecular & Cellular Biomechanics, Vol.1, No.4, pp. 253-266, 2004, DOI:10.3970/mcb.2004.001.253

Abstract Membrane-bound integrin receptors are linked to intracellular signaling pathways through focal adhesion kinase (FAK). FAK tends to colocalize with integrin receptors at focal adhesions through its C-terminal focal adhesion targeting (FAT) domain. Through recruitment and binding of intracellular proteins, FAs transduce signals between the intracellular and extracellular regions that regulate a variety of cellular processes including cell migration, proliferation, apoptosis and detachment from the ECM. The mechanism of signaling through the cell is of interest, especially the transmission of mechanical forces and subsequent transduction into biological signals. One hypothesis relates mechanotransduction to conformational changes in intracellular proteins in the force… More >

M.V. Bayas^1,1, K.Schulten^2,2, D. Leckb,^3,3

Molecular & Cellular Biomechanics, Vol.1, No.2, pp. 101-112, 2004, DOI:10.3970/mcb.2004.001.101

Abstract The force-induced dissociation of the strand dimer interface in C-cadherin has been studied using steered molecular dynamics simulations. The dissociation occurred, without domain unraveling, after the extraction of the conserved trypthophans (Trp2) from their respective hydrophobic pockets. The simulations revealed two stable positions for the Trp2 side chain inside the pocket. The most internal stable position involved a hydrogen bond between the ring Ne of Trp2 and the backbone carbonyl of Glu90. In the second stable position, the aromatic ring is located at the pocket entrance. After extracting the two tryptophans from their pockets, the complex exists in an intermediate… More >

Jianyong Huang, Xiaoling Peng, Chunyang Xiong, Jing Fang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 119-120, 2011, DOI:10.3970/icces.2011.017.119

Abstract Cell-substrate interfacial interplay plays a key role in many fundamental aspects of mammalian physiology. Recent progresses in related experiments concerning cell interactions with extracellular matrix have demonstrated that substrate rigidities can exert a remarkable influence on cell adhesion and spreading dynamics. For example, it has been reported that cell-substrate adhesion strength usually rises monotonically with Young's modulus of underlying elastic substrates and eventually achieves the strongest adhesion on rigid substrates such as glass, and that cell spreading area takes on a growing trend with the increase in substrate hardness and finally reaches a plateau when the stiffness exceeds the order… More >