Search results for "collage"

Compromised nuclear envelope integrity drives TREX1-dependent DNA damage and tumor cell invasion

2021

Although mutations leading to a compromised nuclear envelope cause diseases such as muscular dystrophies or accelerated aging, the consequences of mechanically induced nuclear envelope ruptures are less known. Here, we show that nuclear envelope ruptures induce DNA damage that promotes senescence in non-transformed cells and induces an invasive phenotype in human breast cancer cells. We find that the endoplasmic reticulum (ER)-associated exonuclease TREX1 translocates into the nucleus after nuclear envelope rupture and is required to induce DNA damage. Inside the mammary duct, cellular crowding leads to nuclear envelope ruptures that generate TREX1-dependent DNA damage, thereby driving the …

Influence of retinol on human chondrocytes in agarose culture

1992

Vitamin A and its congeners, collectively called retinoids, are known to have teratogenic potential and have induced craniofacial and limb malformations in numerous animal species. More importantly, retinoids are recognized as teratogenic to fetuses of pregnant women who have taken such preparations for dermatologic disorders. Information gathered from the study of animal models suggests that retinoids interfere with cartilage differentiation. If chondrogenesis in limb development is disturbed it may contribute to limb reductions and malformations. In vitro studies using various animal systems have shown that cartilage matrix macromolecules are altered to resemble those secreted by mesenchy…

Isolation, sequence analysis and characterization of cDNA clones coding for the C chain of mouse C1q. Sequence similarity of complement subcomponent …

1992

A mouse macrophage lambda gt11 cDNA library was screened using a genomic DNA clone coding for the C-chain gene of human C1q. Approximately 600,000 recombinant phage plaques were hybridized with peroxidase-labeled human C-chain probe and detected by enhanced chemiluminescence. Five positive clones were obtained. The size of the full-length cDNA is 1019 bp. The sequence identity of the nucleotide sequence with human C1q C chain is 79%, the identity of the deduced amino acid sequences is 73%. The mouse C1q C chain exhibits the same structural features as the human C chain, e.g. conservation of the cysteine residues. Like the mouse A chain, the mouse C chain has an RGD sequence that may be reco…

Bioactive glass ions induce efficient osteogenic differentiation of human adipose stem cells encapsulated in gellan gum and collagen type I hydrogels

2019

Abstract Background Due to unmet need for bone augmentation, our aim was to promote osteogenic differentiation of human adipose stem cells (hASCs) encapsulated in gellan gum (GG) or collagen type I (COL) hydrogels with bioactive glass (experimental glass 2-06 of composition [wt-%]: Na2O 12.1, K2O 14.0, CaO 19.8, P2O5 2.5, B2O3 1.6, SiO2 50.0) extract based osteogenic medium (BaG OM) for bone construct development. GG hydrogels were crosslinked with spermidine (GG-SPD) or BaG extract (GG-BaG). Methods Mechanical properties of cell-free GG-SPD, GG-BaG, and COL hydrogels were tested in osteogenic medium (OM) or BaG OM at 0, 14, and 21 d. Hydrogel embedded hASCs were cultured in OM or BaG OM fo…

OPLA scaffold, collagen I, and horse serum induce a higher degree of myogenic differentiation of adult rat cardiac stem cells

2009

In the last few years, a major goal of cardiac research has been to drive stem cell differentiation to replace damaged myocardium. Several research groups have attempted to differentiate potential cardiac stem cells (CSCs) using bi- or three-dimensional systems supplemented with growth factors or molecules acting as differentiating substances. We hypothesize that these systems failed to induce a complete differentiation because they lacked an architectural space. In the present study, we isolated a pool of small proliferating and fibroblast-like cells from adult rat myocardium. The phenotype of these cells was assessed and the characterized cells were cultured in a collagen I/OPLA scaffold …

A new method to value efficiency of enzyme blends for pancreas tissue digestion

2010

In pancreatic islets isolation for cell therapy the major enzymes used are obtained from Clostridium hystoliticum: class I and class II collagenases. They are used in a defined tissue dissociation enzyme mixture together with neutral protease (Dispase) or thermolysin (Thermostable Neutral Protease). However, just to now, people working in islets production found variable outcomes in isolation procedures mainly due to large variability in enzymatic blend composition and efficacy. Using electrophoresis and gelatin zymography approaches together with densitometry evaluation assays we compared the composition, stability and auto-digestion processes of C. hystoliticum collagenases, Neutral prote…

C. HYSTOLITICUM RECOMBINANT COLLAGENASES AND METHOD FOR THE MANUFACTURE THEREOF

2010

The present invention relates to the production of recombinant collagenases, and in particular describes a method for the production of recombinant clostridium histolyticum collagenases Col characterized by a yield higher than approximately 140 mg/l of culture of said collagenases in soluble, biologically active form, collagenases produced by this method, compositions comprising these collagenases and the use thereof.

Role of TGF-b1 in type I collagen production in bronchial epithelial cells: effects on Smad7 inhibitory role?

2008

Airway epithelial cells play an important role in inflammatory, apoptotic and remodelling process associate with fibrosis and COPD. Transforming growth factor 1 (TGF-b1) is involved in airways remodelling by Smads signalling pathway. We investigated the role of TGF-b1 on type I collagen production and Smads (Smad 2-3-4-and 7) expression in bronchial epithelial cells (16HBE). Cells were treated with 1ng/ml and 10ng/ml of TGF-b1 for 0, 3 and 24 hours. With low dose of TGF-b1 we observed no significant variation on Smad2 mRNA expression for both times but a significant increased of Smad7 mRNA expression at 3h (p=0.0043) and a significant reduction of Smad3, Smad4 and Smad7 mRNA expression at 2…

Evaluation of a Cell-Free Collagen Type I-Based Scaffold for Articular Cartilage Regeneration in an Orthotopic Rat Model.

2020

The management of chondral defects represents a big challenge because of the limited self-healing capacity of cartilage. Many approaches in this field obtained partial satisfactory results. Cartilage tissue engineering, combining innovative scaffolds and stem cells from different sources, emerges as a promising strategy for cartilage regeneration. The aim of this study was to evaluate the capability of a cell-free collagen I-based scaffold to promote cartilaginous repair after orthotopic implantation in vivo. Articular cartilage lesions (ACL) were created at the femoropatellar groove in rat knees and cell free collagen I-based scaffolds (S) were then implanted into right knee defect for the…

Hydroxyapatite/Chitosan/Collagen coatings through galvanic coupling

In this work, the attention was focused on Hydroxyapatite/ Chitosan/Collagen composite as biocoatings for application in orthopaedic devices. Hydroxyapatite was selected for its osteoconductivity due to its chemical structure similar to bones. Collagen has the same function since 90-95% of bone matrix is constituted of collagen fibers. Furthermore, chitosan are largely used yet in medical field (e.g. antibacterial agent or drug deliver) and in this work were used to create a synergic interaction with hydroxyapatite and collagen to increase the strength and bioactivity of coating. Coatings were fabricated by galvanic deposition process that has different advantages an it does not require ext…