Gel collagen

Other treatments may include fluorouracil/epinephrine/bovine collagen gel, an intralesional injection that has been proven effective in clinical trials for refractory patients, or an intralesional injection of interferon. 

Shirai, Y., Yamaguchi, M., Kobayashi, A., Nishi, A., Nakamura, H., and Murakami, H., Change in Growth Kinetics of Hybridoma Cells Entrapped in Collagen Gel Affected by Alkaline Supply, Cytotechnol., 14 129 (1994)... 

Type XII and XIV collagens may play a role in the organization of the collagen fihrils. When a small aliquot of type XII and XIV collagens is added to the collagen gel with dermal fibroblasts, the gel contracts in a dose-dependent manner. " The N-terminal NC3 domain is responsible for this activity. 

Brain microvascular EC monolayers together with an astrocyte-enriched subendothelial collagen gel can be used to simulate the blood-brain barrier (BBB) (39). Such systems are invaluable to screen for compounds able to penetrate the BBB to access brain tumors or metastases. In addition, glioma cell invasion into brain fragments has enabled better understanding of the properties of these highly invasive tumors and identification of potential therapeutic targets (40). 

Another modification has been described by Nyberg et al. [30]. In this design primary hepatocytes are entrapped in cylindrical collagen gels inside the lumen of the hollow fibres as shown in Fig. 3. The gel entrapment technique reported by this group enables a large number of hepatocytes to be employed in the bioreactor. Additionally, this technique also provides a three-dimensional frame-... 

Toda S, Aoki S, Suzuki K et al (2003) Thyrocytes, but not C cells, actively undergo growth and foUiculogenesis at the periphery of thyroid tissue fragments in tliree-dimensional collagen gel culture. Cell Tissue Res 312(3) 281-289... 

Nagai, N., Mori, K., Satoh, Y., Takahashi, N., Yunoki, S., Tajima, K., and Munekata, M. (2007). In vitro growth and differentiated activities of human periodontal ligament fibroblasts cultured on salmon collagen gel.. Biomed. Mater. Res. 82A, 395-402. 

Nomura, Y., Toki, S., Ishii, Y., and Shirai, K. (2000a). The physicochemical property of shark type I collagen gel and membrane. J. Agric. Food Chem. 48,2028-2032. 

Yunoki, S., Nagai, N., Suzuki, T., and Munekata, M. (2004). Novel biomaterial from reinforced salmon collagen gel prepared by fibril formation and cross-linking. J. Biosci. Bioeng. 98, 40-47. 

Djabourov, M., Lechaire, J. P., and Gaill, F. (1993). Structure and rheology of gelatin and collagen gels. Biorheology 30,191-205. 

The success of cellular therapies ultimately depends on the stability of the hepatocyte in the architecture in which it must exist. Primary hepatocytes are anchorage dependent. Isolated cells rapidly lose viability when cultured in monolayers or suspensions. Investigators have developed culture models based on features of liver architecture to recapitulate the complex hepatocyte microenvironment. Sandwich culture mimics the environment of hepatocytes in vivo by entrapping cells between two layers of collagen gel. However, such methods introduce additional transport barriers and are difficult to scale up to therapeutic levels. ... 

Zamora, P.O., Benson, J.M., Marshall, T.C., Mokler, B.V, Li, A.P, Dahl, A.R., Brooks, A.L. McClellan, R.O. (1983) Cytotoxicity and mutagenicity of vapor-phase pollutants in rat lung epithelial cells and Chinese hamster ovary cells grown on collagen gels. J. Toxicol, environ. Health, 12,27-38... 

Of the different types of oral mucosal cell cultures that have been used [47,48], the most commonly used ones are explants of primary cultures. Small pieces of excised buccal or sublingual tissue are placed in a support system and fed with culture medium. The outgrowths obtained from these tissue explants are then transferred and grown in appropriate media. For example, outgrowths of fibroblasts [49] thus obtained have been described. Gibbs and Ponec [50] reconstructed the epithelium of mucosal tissue by placing a tissue biopsy (with the epithelial side upwards) onto a fibroblast-populated collagen gel. The explants obtained were cultured immediately at the air liquid interface until the epithelium had expanded over the gel (2-3 weeks). These explant cultures may retain many of the in vivo tissue characteristics. 

Fig. 1.2 Demonstration of permeation of FD C Red Dye through collagen gel over 48 h A-D vials represent 95%, 85% and 65% water by weight the diffusion of the dye (consists of red and yellow dyes) is nearly constant regardless of the water concentration...

REPRESENTATIVE MICROSTRUCTURE FINITE ELEMENTS FOR COLLAGEN GELS... 

Abstract We present a method for simulation of collagen gels and more generally for materials comprised of a fibrillar network. The method solves a representative microstructural problem on each finite element in lieu of a constitutive equation. The method captures key features of microstructural rearrangement while maintaining the ability to perform simulations on the (large) functional length scale. 

Representative Micro structure Finite Elements for Collagen Gels... 

Figure 5. Immunohistochemical staining of phosphorylated EGFR in A431 epidermoid cell lines. Tissues from A431 xenograft bearing SCID mouse (A) and 3D-cultured A431 cells in collagen gel (B) were formalin-fixed, paraffin-embedded, and used for method validation.

Kobayashi H, Higashiyama M, Minamigawa K, et al. Examination of in vitro chemosensitivity test using collagen gel droplet culture method with colorimetric endpoint quantification. Jpn. J. Cancer Res. 2001 92 203-210. 

Instead of agarose gel cultures, some authors use 3D chondrocyte clusters in suspension (Bassleer et al. 1990, 1992 Henrotin et al. 1992), or suspensions over agarose (Archer et al. 1990), or embedded in collagen gels (Malemud et al. 1994). 

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