scholarly journals The effect of the fibre orientation of electrospun scaffolds on the matrix production of rabbit annulus fibrosus-derived stem cells

Bone Research ◽  
2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Chen Liu ◽  
Caihong Zhu ◽  
Jun Li ◽  
Pinghui Zhou ◽  
Min Chen ◽  
...  
Keyword(s):  
Stem Cells ◽  
Annulus Fibrosus ◽  
Fibre Orientation ◽  
Electrospun Scaffolds ◽  
The Matrix ◽  
Matrix Production

Structural engineering to control density, conformation, and bioactivity of the poly(ethylene glycol)-grafted poly(urethane urea) scaffolds

2018 ◽  
Vol 34 (2) ◽  
pp. 209-223
Author(s):  
Shideh Shaneh ◽  
Fatemeh Shokrolahi ◽  
Parvin Shokrollahi ◽  
Hamid Yeganeh ◽  
Hossein Omidian
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Ethylene Glycol ◽  
Structural Engineering ◽  
Cell Attachment ◽  
Poly Ethylene Glycol ◽  
Salt Leaching ◽  
The Matrix ◽  
Diphenyl Tetrazolium Bromide ◽  
Poly Ethylene

Poly(urethane urea) scaffolds were fabricated through combined salt leaching and solvent casting methods. The scaffolds were then functionalized via aminolysis with poly(ethylene glycol) (PEG- g-PUU). To compare its bioactivity, gelatin was also grafted onto the aminolyzed poly(urethane urea) surface (Gel- g-PUU). Chemical changes at the surface were then monitored using quantitative/qualitative methods. Grafting with both gelatin and poly(ethylene glycol) remarkably enhanced the wettability of poly(urethane urea). Proliferation of human adipose–derived mesenchymal stem cells on poly(urethane urea) and the modified poly(urethane urea)s was evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay. The cell experiment results showed that both the modified poly(urethane urea)s enhanced the attachment and proliferation of human adipose–derived mesenchymal stem cells compared to pure poly(urethane urea). Based on previous reports, while a supportive role is observed at adequate poly(ethylene glycol) graft densities, cell adhesion and proliferation are inhibited at very high grafting densities. To correlate the cell data to poly(ethylene glycol) conformations, the surface tension was measured. Data on human adipose–derived mesenchymal stem cells’ attachment/proliferation and contact angle/surface free energy together showed that the grafting density of poly(ethylene glycol) was regulated by optimizing aminolysis conditions, careful selection of poly(ethylene glycol)’s molecular weight, and bulk properties of the matrix poly(urethane urea). As a result, surface overcrowding and brush conformation of the poly(ethylene glycol) chains were avoided, and human adipose–derived mesenchymal stem cell attachment and proliferation occurred on the PEG- g-PUU scaffold at a comparable level to the Gel- g-PUU.

scholarly journals Inorganic polyphosphates stimulates matrix production in human annulus fibrosus cells

JOR Spine ◽  
2021 ◽  
Author(s):  
Xiangjiang Wang ◽  
Rahul Gawri ◽  
Changbin Lei ◽  
Joon Lee ◽  
Gwendolyn Sowa ◽  
...  
Keyword(s):  
Annulus Fibrosus ◽  
Inorganic Polyphosphates ◽  
Matrix Production

scholarly journals Laminin-5 activates extracellular matrix production and osteogenic gene focusing in human mesenchymal stem cells

2007 ◽  
Vol 26 (2) ◽  
pp. 106-114 ◽  
Author(s):  
Robert F. Klees ◽  
Roman M. Salasznyk ◽  
Scott Vandenberg ◽  
Kristin Bennett ◽  
George E. Plopper
Keyword(s):  
Stem Cells ◽  
Extracellular Matrix ◽  
Mesenchymal Stem Cells ◽  
Human Mesenchymal Stem Cells ◽  
Laminin 5 ◽  
Extracellular Matrix Production ◽  
Matrix Production ◽  
Osteogenic Gene

scholarly journals Differentiation of cardiomyocytes from human embryonic stem cells is accompanied by changes in the extracellular matrix production of versican and hyaluronan

2010 ◽  
Vol 111 (3) ◽  
pp. 585-596 ◽  
Author(s):  
Christina K. Chan ◽  
Marsha W. Rolle ◽  
Susan Potter-Perigo ◽  
Kathleen R. Braun ◽  
Benjamin P. Van Biber ◽  
...  
Keyword(s):  
Stem Cells ◽  
Extracellular Matrix ◽  
Embryonic Stem Cells ◽  
Human Embryonic Stem Cells ◽  
Embryonic Stem ◽  
Extracellular Matrix Production ◽  
Matrix Production

scholarly journals Characterization of continuous Hibiscus sabdariffa fibre reinforced epoxy composites

2022 ◽  
Vol 30 ◽  
pp. 096739112110609
Author(s):  
Atik Mubarak Kazi ◽  
Ramasastry DVA
Keyword(s):  
Fibre Orientation ◽  
Stress Transfer ◽  
Dynamic Mechanical Properties ◽  
Epoxy Composites ◽  
Neat Epoxy ◽  
Hibiscus Sabdariffa ◽  
Sem Images ◽  
Fibre Composites ◽  
The Matrix

The influence of fibre orientation on physical, mechanical and dynamic mechanical properties of Hibiscus sabdariffa fibre composites has been studied. The composites with longitudinal (0°), transverse (90°) and inclined (45°) fibre orientation were prepared using the hand layup technique. ASTM standards were used for characterization of continuous Hibiscus sabdariffa fibre composites. The composite with longitudinally placed fibres yields improved mechanical characteristics. The addition of longitudinal (0°) oriented continuous Hibiscus sabdariffa fibres to the epoxy enhances tensile strength by 460%, flexural strength by 160% and impact strength by 603% compared to neat epoxy. The longitudinal (0°) fibre oriented composite offers higher resistance to water absorption and thickness swelling compared to other types of composites. All continuous Hibiscus sabdariffa fibre epoxy composites possess an improved storage modulus than the neat epoxy resin. The glass transition temperature of continuous Hibiscus sabdariffa fibre composites is 8%–31% lower than that of neat epoxy. Scanning electron microscopy (SEM) images confirm the existence of voids in the matrix, fibre pullout and crack propagation near the fibre bundle, which indicates the stress transfer between fibre and matrix is non-uniform.

Compartmentalization of the matrix formed by nucleus pulposus and annulus fibrosus cells in alginate gel

2002 ◽  
Vol 30 (6) ◽  
pp. 874-878 ◽  
Author(s):  
E. Thonar ◽  
H. An ◽  
K. Masuda
Keyword(s):  
Nucleus Pulposus ◽  
Annulus Fibrosus ◽  
Articular Chondrocyte ◽  
Alginate Gel ◽  
Age Related ◽  
The Matrix ◽  
Disc Cells ◽  
A Cell ◽  
Associated Matrix

Intervertebral disc cells cultured in alginate gel are capable of reforming in alginate, a matrix that consists of two compartments: a rim of metabolically active cell-associated matrix and a more abundant, but metabolically less active, further removed matrix. At any one age and in most species, the cell-associated matrix formed by a nucleus pulposus or annulus fibrosus cell cultured in this way is less abundant than that formed by an articular chondrocyte. In both the cell-associated matrix and further removed matrix, the ratio of aggrecan to collagen is significantly higher in the case of nucleus pulposus than of annulus fibrosus, a feature that also distinguishes the matrices of the nucleus pulposus and annulus fibrosus in vivo. Nucleus pulposus and annulus fibrosus cells from older donors show a decreased ability to reform a cell-associated matrix rich in aggrecan. There is, however, some evidence that gene therapy and/or exposure of the cells to defined stimulatory factors can help overcome some of these age-related limitations. This contention is supported by recent evidence that nucleus pulposus and annulus fibrosus cells from adult donors can be manipulated to form, using the recently developed alginate-recovered chondrocyte system, a resilient tissue that bears many of the characteristics of the tissue in which these cells reside in vivo.

The Formation and Properties of the Organic Matrix of Reptilian Tooth Enamel

1957 ◽  
Vol s3-98 (43) ◽  
pp. 349-367
Author(s):  
D.F. G. POOLE
Keyword(s):  
Tooth Enamel ◽  
Organic Matrix ◽  
Enamel Formation ◽  
Positive Form ◽  
Form Birefringence ◽  
Parallel Fibres ◽  
The Matrix ◽  
Elementary State ◽  
Simple Step ◽  
Matrix Production

A number of features of enamel formation in the lizard Agama atricollis are described. The behaviour and properties of the ameloblasts indicate that the process of enamel formation is similar to the corresponding process in mammals; the fibrous enamel matrix appears to be formed from outgrowths of the cytoplasm of these cells. Interprismatic material, as it is known in mammals, is not produced, so that reptilian matrix tends to be uniformly fibrous. Nevertheless, the fibres are initially arranged in groups corresponding to the ameloblasts. There is no distinct pre-enamel stage because matrix production is immediately followed by a limited influx of mineral in an elementary state, converting the matrix into an basiphil form. Striae of Retzius may be due to periodic pauses in the normal process of matrix production enabling the ameloblasts to assimilate and secrete mineral. Before the onset of final calcification, the matrix seems to undergo a modification rendering it capable of influencing the size and orientation of mineral crystallites. The organic matrix has a refractive index of 1.57 and has no intrinsic birefringence. However, in suitable liquids the parallel fibres produce a positive form birefringence. If paraffin wax is allowed to crystallize on the matrix, optically negative streaks are formed parallel with the fibres, perhaps as the result of crystal overgrowth. Evidence obtained indicates that this reptilian type of ectodermal enamel is a likely precursor of the mammalian prismatic type. The evolution from one to the other could have been achieved in a comparatively simple step.

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