Search results for "Collagen"
showing 10 items of 620 documents
Immunohistochemical evaluation of matrix molecules associated with wound healing following treatment with an enamel matrix protein derivative in huma…
2003
Application of enamel matrix protein derivative (EMD) onto a debrided and conditioned root surface has been shown to promote periodontal regeneration in animals and humans. However, until now there is virtually no information from humans describing the expression of different matrix molecules in the newly formed periodontal tissues following treatment with EMD. This study investigated immunohistochemically in humans the expression of matrix molecules associated with periodontal tissues reformed after treatment with EMD. Eight patients with intrabony defects were treated with EMD. Six months after surgery teeth together with some of their surrounding soft and hard tissues were removed, fixed…
Blockage of collagen binding to integrin α2β1: structure–activity relationship of protein–protein interaction inhibitors
2011
The interaction between the α2β1 integrin and collagen plays a crucial role in the development of pathological conditions, such as thrombus formation and cancer cell metastasis. Accordingly, the α2β1 integrin is a promising target for the development of new drug molecules to treat these diseases. Here, we have designed, synthesized, and measured in vitro a set of novel drug-like compounds that block the protein–protein interactions between α2β1 integrin and collagen. The obtained structure–activity relationship reveals the key features that are required for successful inhibition of this integrin–collagen interaction.
A comparison of spreading and motility behaviour of 8701-BC breast carcinoma cells on type I, I-trimer and type V collagen substrata. Evidence for a …
1991
Ductal infiltrating carcinoma (d.i.c.) of human breast is a highly invasive neoplasm characterized by enhanced deposition of collagen. Paradoxically, enhanced collagen deposition is not correlated with inhibition of the migration of tumour cells into the host tissue. d.i.c. is characterized by the reappearance of ‘embryonic’ type I-trimer collagen and an increase in type V collagen content in the matrix. The effects of these two collagen types were compared with type I collagen as culture substrata on the spreading pattern, cytoskeletal organization and motile behaviour of 8701-BC breast carcinoma cells using rhodamine-phalloidin staining, a DNAase I-competition assay, scanning electron mic…
Type V collagen regulates the expression of apoptotic and stress response genes by breast cancer cells.
2004
Type V collagen is a "minor" component of normal human breast stroma, which is subjected to over-deposition in cases of ductal infiltrating carcinoma (DIC). We reported that, if used as a culture substrate for the DIC cell line 8701-BC, it exhibited poorly-adhesive properties and restrained the proliferative and motile behavior of the cell subpopulation able to attach onto it. Moreover, this collagen species was able to trigger DNA fragmentation and impair survival of 8701-BC cells. In this study, we have extended our investigation with the aim to obtain further evidence that the death induced by type V collagen was of the apoptotic type by (i) microscopic detection and quantitation of Apop…
Activation of the first component of complement, C1: comparison of the effect of sixteen different enzymes on serum C1.
1983
In this study, the effect of sixteen different enzymes on serum C1 and its subcomponents was investigated. The sixteen enzymes could be divided into three groups. First, enzymes which activate native C1: trypsin (optimal concentration 2.4 x 10(-4) mM); alpha-chymotrypsin (2.3 x 10(3) mM); thrombin (1.0 x 10(-5) mM); plasmin (1.9 x 10(-5) mM); elastase (5.8 x 10(-5) mM); pronase (3.0 x 10(-6) mM). All these enzymes are serine esterase and activate native serum C1 bound to EAC4 at the given concentration within 10 min at 30 degrees C. Furthermore, native C1 inhibited by a pentosanpolysulfoester, Sp54, is unable to undergo the internal activation but can be externally activated by the serine e…
SPIONs embedded in polyamino acid nanogels to synergistically treat tumor microenvironment and breast cancer cells.
2018
Abstract The extremely complex tumor microenvironment (TME) in humans is the major responsible for the therapeutic failure in cancer nanomedicine. A new concept of disease-driven nanomedicine, henceforth named “Theranomics”, which attempts to target cancer cells and TME on the whole, represents an attractive alternative. Herein, a nanomedicine able to co-deliver doxorubicin and a tumor suppressive proteolytic protein such as collagenase-2 was developed. We successfully obtained superparamagnetic nanogels (SPIONs/Doco@Col) via the intermolecular azide-alkyne Huisgen cycloaddition. We demonstrated that a local ECM degradation and remodeling in solid tumors by means of collagenase-2 could enha…
Influence of scaffold pore size on collagen I development: A new in vitro evaluation perspective
2013
Bone tissue engineering takes part in the complex process of bone healing by combining cells, chemical/physical signals, and scaffolds with the scaffolds providing an artificial extracellular matrix network. The role of the support template for cell activity is crucial to guide the healing process. This in vitro study compared three different poly(D,L-lactic acid) scaffolds obtained by varying the pore size generated by applying different salt leaching processes. The influence of pore dimensions on the extracellular matrix produced by human osteosarcoma-derived osteoblasts (MG63 cell line) seeded on these different materials was analyzed. This study is targeted on the intermediate stage of…
Blood absorption capacity of different xenograft bone substitutes. An in-vitro study
2019
Background Commercially available xenograft blocks, claim to have adequate characteristics to interact with biological media and thus permitting biological fluid absorption. The objective of this in vitro study was to compare the blood absorption capacity of four different xenograft block materials of different composition of collagen and porosity. Material and Methods Four brands of xenograft block materials were used (NuOss®, Bio-Oss®, Osteobiol® and Smartbone®). Five samples of each brand were analyzed, making a total of 20 tests. Human blood was used as the absorption liquid for the present experiment. The time period, in which the block remains in contact with the blood, was registered…
Autofluorescence imaging of basal cell carcinoma by smartphone RGB camera
2015
The feasibility of smartphones for in vivo skin autofluorescence imaging has been investigated. Filtered autofluorescence images from the same tissue area were periodically captured by a smartphone RGB camera with subsequent detection of fluorescence intensity decreasing at each image pixel for further imaging the planar distribution of those values. The proposed methodology was tested clinically with 13 basal cell carcinoma and 1 atypical nevus. Several clinical cases and potential future applications of the smartphone-based technique are discussed.