scholarly journals Polydopamine-Based Interfacial Engineering of Extracellular Matrix Hydrogels for the Construction and Long-Term Maintenance of Living Three-Dimensional Tissues

2019 ◽  
Vol 11 (27) ◽  
pp. 23919-23925 ◽  
Author(s):  
Sunghee E. Park ◽  
Andrei Georgescu ◽  
Jeong Min Oh ◽  
Keon Woo Kwon ◽  
Dongeun Huh
Keyword(s):  
Extracellular Matrix ◽  
Three Dimensional ◽  
Interfacial Engineering ◽  
Term Maintenance

scholarly journals Three-dimensional carbon nanotube scaffolds for long-term maintenance and expansion of human mesenchymal stem cells

2017 ◽  
Vol 105 (7) ◽  
pp. 1927-1939 ◽  
Author(s):  
Gaurav Lalwani ◽  
Michael D'agati ◽  
Anu Gopalan ◽  
Sunny C. Patel ◽  
Yahfi Talukdar ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Carbon Nanotube ◽  
Three Dimensional ◽  
Human Mesenchymal Stem Cells ◽  
Term Maintenance

scholarly journals Three-Dimensional Extracellular Matrix Scaffolds by Microfluidic Fabrication for Long-Term Spontaneously Contracted Cardiomyocyte Culture

2014 ◽  
Vol 20 (21-22) ◽  
pp. 2931-2941 ◽  
Author(s):  
Jeng-Chun Mei ◽  
Aden Yuan Kun Wu ◽  
Po-Chen Wu ◽  
Nai-Chen Cheng ◽  
Wei-Bor Tsai ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Three Dimensional ◽  
Cardiomyocyte Culture ◽  
Extracellular Matrix Scaffolds

scholarly journals Interleukin-1 β regulation of fibroblast proteoglycan synthesis involves a decrease in versican steady-state mRNA levels

1993 ◽  
Vol 294 (2) ◽  
pp. 613-620 ◽  
Author(s):  
E E Qwarnström ◽  
H T Järveläinen ◽  
M G Kinsella ◽  
C O Ostberg ◽  
L J Sandell ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Steady State ◽  
Chondroitin Sulphate ◽  
Interleukin 1 ◽  
Mrna Level ◽  
Three Dimensional ◽  
Proteoglycan Synthesis ◽  
Mrna Levels ◽  
Pronounced Decrease

This study investigates the effects of interleukin (IL)-1 beta on proteoglycan metabolism by fibroblasts surrounded by endogenous extracellular matrix. In both three-dimensional matrix cultures and long-term monolayer cultures IL-1 beta caused a significant decrease in synthesis and deposition of sulphated proteoglycans, but had no effect on release of deposited material. The decrease in synthesis became successively more pronounced, and corresponded to 40-60% of the control after 72 h incubation. The reduction was almost totally accounted for by an effect on the chondroitin ABC-lyase-sensitive proteoglycans. Gel electrophoresis showed a significant decrease in a high-molecular-mass chondroitin ABC-lyase-sensitive proteoglycan after incubation with IL-1 beta. Northern-blot analyses of total RNA revealed a pronounced decrease in the steady-state mRNA levels of versican, the large chondroitin sulphate, with levels corresponding to 10-30% of controls. In comparison, the steady-state mRNA level for decorin, the major sulphated proteoglycan synthesized by the cells, was only slightly affected. The prominent decrease in synthesis of sulphated proteoglycans induced in long-term fibroblast cultures, including the pronounced decrease in versican steady-state mRNA levels, is likely to have a significant effect on the structure of the extracellular matrix. Induction of this type of change may constitute a significant mechanism whereby IL-1 beta can affect the properties of connective tissue during inflammation and wound healing.

Three-dimensional Co-culture of Primary Human Liver Cells in Bioreactors for In Vitro Drug Studies: Effects of the Initial Cell Quality on the Long-term Maintenance of Hepatocyte-specific Functions

2002 ◽  
Vol 30 (5) ◽  
pp. 525-538 ◽  
Author(s):  
Katrin Zeilinger ◽  
Igor M. Sauer ◽  
Gesine Pless ◽  
Catrin Strobel ◽  
Jeannette Rudzitis ◽  
...  
Keyword(s):  
Pharmaceutical Industry ◽  
Human Liver ◽  
Three Dimensional ◽  
Liver Cells ◽  
Bioreactor Culture ◽  
Initial Cell ◽  
Human Liver Cells ◽  
Term Maintenance

In vitro culture models that employ human liver cells could be potent tools for predictive studies on drug toxicity and metabolism in the pharmaceutical industry. A bioreactor culture model was developed that permits the three-dimensional co-culture of liver cells under continuous medium perfusion with decentralised mass exchange and integral oxygenation. We tested the ability of the system to support the long-term maintenance and differentiation of primary human liver cells. The effects of the initial cell quality were investigated by comparing cultures from resected, non-preserved liver with cultures from liver graft tissue damaged by long-term preservation. In cultures originating from non-preserved liver, protein and urea synthesis, glucose metabolism, and cytochrome (P450) activities were stable over the 2-week culture period, with maximal activities at the end of the first week in culture. Enzyme induction led to increased 7-ethoxyresorufin O-deethylase activities of up to 20 times the basal value. In cultures from preservation-damaged liver, recovery of metabolic activities was detected during bioreactor culture. After two weeks, most biochemical parameters approached those of cultures from non-preserved human liver. Light microscopy demonstrated the three-dimensional reorganisation of hepatocytes and nonparenchymal cells in co-culture. Long-term maintenance, and even the regeneration of specific functional activities of human liver cells, can be achieved in the bioreactor. This could facilitate the introduction into the pharmaceutical industry of in vitro drug testing with primary human liver cells.

scholarly journals Induction of Autophagy during Extracellular Matrix Detachment Promotes Cell Survival

2008 ◽  
Vol 19 (3) ◽  
pp. 797-806 ◽  
Author(s):  
Christopher Fung ◽  
Rebecca Lock ◽  
Sizhen Gao ◽  
Eduardo Salas ◽  
Jayanta Debnath
Keyword(s):  
Extracellular Matrix ◽  
Cell Death ◽  
Cell Survival ◽  
Three Dimensional ◽  
Clonogenic Survival ◽  
Mammary Epithelial ◽  
Lumen Formation ◽  
Stable Reduction ◽  
Promote Cell Death

Autophagy has been proposed to promote cell death during lumen formation in three-dimensional mammary epithelial acini because numerous autophagic vacuoles are observed in the dying central cells during morphogenesis. Because these central cells die due to extracellular matrix (ECM) deprivation (anoikis), we have directly interrogated how matrix detachment regulates autophagy. Detachment induces autophagy in both nontumorigenic epithelial lines and in primary epithelial cells. RNA interference-mediated depletion of autophagy regulators (ATGs) inhibits detachment-induced autophagy, enhances apoptosis, and reduces clonogenic recovery after anoikis. Remarkably, matrix-detached cells still exhibit autophagy when apoptosis is blocked by Bcl-2 overexpression, and ATG depletion reduces the clonogenic survival of Bcl-2–expressing cells after detachment. Finally, stable reduction of ATG5 or ATG7 in MCF-10A acini enhances luminal apoptosis during morphogenesis and fails to elicit long-term luminal filling, even when combined with apoptotic inhibition mediated by Bcl-2 overexpression. Thus, autophagy promotes epithelial cell survival during anoikis, including detached cells harboring antiapoptotic lesions.

Practical electron tomography

1995 ◽  
Vol 53 ◽  
pp. 742-743
Author(s):  
C.L. Woodcock
Keyword(s):  
Electron Tomography ◽  
Tomographic Reconstruction ◽  
Three Dimensional ◽  
3D Shape ◽  
Computational Resources ◽  
Shape Of Particles

Despite the potential of the technique, electron tomography has yet to be widely used by biologists. This is in part related to the rather daunting list of equipment and expertise that are required. Thanks to continuing advances in theory and instrumentation, tomography is now more feasible for the non-specialist. One barrier that has essentially disappeared is the expense of computational resources. In view of this progress, it is time to give more attention to practical issues that need to be considered when embarking on a tomographic project. The following recommendations and comments are derived from experience gained during two long-term collaborative projects.Tomographic reconstruction results in a three dimensional description of an individual EM specimen, most commonly a section, and is therefore applicable to problems in which ultrastructural details within the thickness of the specimen are obscured in single micrographs. Information that can be recovered using tomography includes the 3D shape of particles, and the arrangement and dispostion of overlapping fibrous and membranous structures.

Efficacious long-term maintenance therapy with pantoprazole (PAN) in patients with Zollinger-Ellison syndrome

2001 ◽  
Vol 120 (5) ◽  
pp. A613-A613
Author(s):  
P BORNMAN ◽  
K RADEBOLD ◽  
H DEBAERE ◽  
L VENTER ◽  
H HEINZE ◽  
...  
Keyword(s):  
Maintenance Therapy ◽  
Zollinger Ellison Syndrome ◽  
Term Maintenance
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