Is there a universal mechanism of cell alignment in response to substrate topography?

Cytoskeleton ◽  
2021 ◽  
Author(s):  
Claire Leclech ◽  
Abdul I. Barakat
Keyword(s):  
Cell Alignment ◽  
Substrate Topography ◽  
Universal Mechanism

DYNAMICS OF BARLEY FLAVONOID AND PRODUCTIVITY UNDER UF-A RADIATION

1970 ◽  
pp. 14-18
Author(s):  
L. I. Goncharova ◽  
P. N. Tsygvintsev ◽  
О. А. Guseva
Keyword(s):  
Grain Yield ◽  
Defense Mechanisms ◽  
Antioxidant Defense ◽  
Malonic Dialdehyde ◽  
Growth Period ◽  
Negative Effects ◽  
Uv Spectrum ◽  
Quantum Energy ◽  
Dry Soil ◽  
Universal Mechanism

The effect of increased UV-A radiation during the ontogeny of barley plants of the Vladimir variety in the vegetation experiment was studied. Changes in the content of malonic dialdehyde, flavonoids and grain yield were revealed. UV-A radiation as compared to UV-B radiation, has lower quantum energy and can have both positive and negative effects on plant regulatory and photosynthetic processes. One of the most damaging effects of increased levels of UV-A radiation is oxidative stress, which causes lipid peroxidation of biological membranes. The existence of a plant cell in such conditions is possible only thanks to a system of antioxidant defense mechanisms. The accumulation of phenolic compounds under the action of UV radiation is a universal mechanism of protection against photodamage, which was formed in the early stages of the evolution of photoautotrophic organisms. Flavonoids are localized in the epidermis of plant tissues and act as an internal filter. The content of flavonoids is determined by the genotype and due to ontogenetic patterns. Plants were grown in a greenhouse, in vessels containing 4.5 kg of air-dry soil. The repetition is threefold (3 vessels in each variant). Sowing density - 13 plants in each vessel. As a source of UV-A radiation used lamps Black Light BLUE company Philips. Plants were irradiated for 5 hours a day from 10 to 15 hours at 13, 25, 34, 43 and 52 stages of organogenesis. The magnitude of the daily biologically effective dose of UV-A radiation was 60.7 kJ / m2. The solar part of the UV spectrum in the vegetation experiment was absent in the greenhouse. The nature of changes in the content of flavonoids under the action of UV-A irradiation during the growing season of plants with the dynamics of the oxidative process has been established. The first maximum was observed during the vegetative growth period, the second - at the earing stage. The data obtained indicate that flavonoids have ontogenetic conditionality and perform photoprotective functions. The increase in their content under the action of UV-A radiation is accompanied by an increase in resistance to photodamage, which is confirmed by the formation of grain yield.

Biological cell alignment for electrofusion

1992 ◽  
Vol 139 (3) ◽  
pp. 112
Author(s):  
S.J. MacDonald ◽  
P.S. Bodger ◽  
P.A. Elder
Keyword(s):  
Biological Cell ◽  
Cell Alignment

scholarly journals Thermoplastic Elastomer (TPE)–Poly(Methyl Methacrylate) (PMMA) Hybrid Devices for Active Pumping PDMS-Free Organ-on-a-Chip Systems

Biosensors ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 162
Author(s):  
Mathias Busek ◽  
Steffen Nøvik ◽  
Aleksandra Aizenshtadt ◽  
Mikel Amirola-Martinez ◽  
Thomas Combriat ◽  
...  
Keyword(s):  
Methyl Methacrylate ◽  
Drug Testing ◽  
Low Cost ◽  
Thermoplastic Elastomer ◽  
Bonding Process ◽  
Cell Alignment ◽  
Poly Methyl Methacrylate ◽  
Bonding Parameters ◽  
Organ On A Chip ◽  
Hybrid Devices

Polydimethylsiloxane (PDMS) has been used in microfluidic systems for years, as it can be easily structured and its flexibility makes it easy to integrate actuators including pneumatic pumps. In addition, the good optical properties of the material are well suited for analytical systems. In addition to its positive aspects, PDMS is well known to adsorb small molecules, which limits its usability when it comes to drug testing, e.g., in organ-on-a-chip (OoC) systems. Therefore, alternatives to PDMS are in high demand. In this study, we use thermoplastic elastomer (TPE) films thermally bonded to laser-cut poly(methyl methacrylate) (PMMA) sheets to build up multilayered microfluidic devices with integrated pneumatic micro-pumps. We present a low-cost manufacturing technology based on a conventional CO2 laser cutter for structuring, a spin-coating process for TPE film fabrication, and a thermal bonding process using a pneumatic hot-press. UV treatment with an Excimer lamp prior to bonding drastically improves the bonding process. Optimized bonding parameters were characterized by measuring the burst load upon applying pressure and via profilometer-based measurement of channel deformation. Next, flow and long-term stability of the chip layout were measured using microparticle Image Velocimetry (uPIV). Finally, human endothelial cells were seeded in the microchannels to check biocompatibility and flow-directed cell alignment. The presented device is compatible with a real-time live-cell analysis system.

scholarly journals Akt signaling is activated by TGFβ2 and impacts tenogenic induction of mesenchymal stem cells

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Sophia K. Theodossiou ◽  
Jett B. Murray ◽  
LeeAnn A. Hold ◽  
Jeff M. Courtright ◽  
Anne M. Carper ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Signaling Pathways ◽  
Transforming Growth Factor ◽  
Akt Signaling ◽  
Cell Alignment ◽  
Limited Information ◽  
Akt Inhibitor ◽  
Tenogenic Differentiation

Abstract Background Tissue engineered and regenerative approaches for treating tendon injuries are challenged by the limited information on the cellular signaling pathways driving tenogenic differentiation of stem cells. Members of the transforming growth factor (TGF) β family, particularly TGFβ2, play a role in tenogenesis, which may proceed via Smad-mediated signaling. However, recent evidence suggests some aspects of tenogenesis may be independent of Smad signaling, and other pathways potentially involved in tenogenesis are understudied. Here, we examined the role of Akt/mTORC1/P70S6K signaling in early TGFβ2-induced tenogenesis of mesenchymal stem cells (MSCs) and evaluated TGFβ2-induced tenogenic differentiation when Smad3 is inhibited. Methods Mouse MSCs were treated with TGFβ2 to induce tenogenesis, and Akt or Smad3 signaling was chemically inhibited using the Akt inhibitor, MK-2206, or the Smad3 inhibitor, SIS3. Effects of TGFβ2 alone and in combination with these inhibitors on the activation of Akt signaling and its downstream targets mTOR and P70S6K were quantified using western blot analysis, and cell morphology was assessed using confocal microscopy. Levels of the tendon marker protein, tenomodulin, were also assessed. Results TGFβ2 alone activated Akt signaling during early tenogenic induction. Chemically inhibiting Akt prevented increases in tenomodulin and attenuated tenogenic morphology of the MSCs in response to TGFβ2. Chemically inhibiting Smad3 did not prevent tenogenesis, but appeared to accelerate it. MSCs treated with both TGFβ2 and SIS3 produced significantly higher levels of tenomodulin at 7 days and morphology appeared tenogenic, with localized cell alignment and elongation. Finally, inhibiting Smad3 did not appear to impact Akt signaling, suggesting that Akt may allow TGFβ2-induced tenogenesis to proceed during disruption of Smad3 signaling. Conclusions These findings show that Akt signaling plays a role in TGFβ2-induced tenogenesis and that tenogenesis of MSCs can be initiated by TGFβ2 during disruption of Smad3 signaling. These findings provide new insights into the signaling pathways that regulate tenogenic induction in stem cells.

Engineering muscle cell alignment through 3D bioprinting

2017 ◽  
Vol 105 (9) ◽  
pp. 2582-2588 ◽  
Author(s):  
Pamela Mozetic ◽  
Sara Maria Giannitelli ◽  
Manuele Gori ◽  
Marcella Trombetta ◽  
Alberto Rainer
Keyword(s):  
Muscle Cell ◽  
3D Bioprinting ◽  
Cell Alignment

scholarly journals Coupling between apical tension and basal adhesion allow epithelia to collectively sense and respond to substrate topography over long distances

2015 ◽  
Vol 7 (12) ◽  
pp. 1611-1621 ◽  
Author(s):  
Kyle E. Broaders ◽  
Alec E. Cerchiari ◽  
Zev J. Gartner
Keyword(s):  
Substrate Topography ◽  
Cell Substrate ◽  
Sense And Respond ◽  
Cell Medium ◽  
Cell Cell

Epithelia have the capacity to sense and respond to substrate topography through the coupling of tensions at the cell–cell, cell–substrate, and cell–medium interfaces.

scholarly journals Prediction and validation of cell alignment along microvessels as order principle to restore tissue architecture in liver regeneration

2010 ◽  
Vol 107 (23) ◽  
pp. 10371-10376 ◽  
Author(s):  
S. Hoehme ◽  
M. Brulport ◽  
A. Bauer ◽  
E. Bedawy ◽  
W. Schormann ◽  
...  
Keyword(s):  
Liver Regeneration ◽  
Cell Alignment ◽  
Tissue Architecture
Sign in / Sign up

Export Citation Format

Share Document