Thus energy storage (elastic properties) and dissipation (viscous properties) are important characteristics of extracellular matrices

METHODS: A uniaxial incremental stress relaxation test method has been used to characterize the time-dependent (viscous) and time-independent (elastic) properties of human dermis. Viscoelasticity was investigated in processed human dermis that was equilibrated at pHs of 3, 7 and 11 in an effort to study the link between electrostatic interactions within the collagen matrix and RESULTS: Our results show that the solution pH and the charge on collagen significantly affected the high-strain elastic behavior of dermis; the elastic behavior of skin has previously been shown to be directly correlated with axial stretching of the collagen triple helix in crosslinked collagen fibrils. A positive linear correlation existed between the high-strain elastic modulus and on the surface of collagen molecules in processed human skin influence the high-strain elastic properties of dermis and are likely to be involved in CONCLUSION: It is proposed that the pH and charged residue dependency of the elastic modulus suggests that charged pair interactions and repulsions within and between collagen molecules are involved in elastic energy storage during stretching at high strains. It is hypothesized that elastic energy storage is associated with the stretching of pairs of charged amino acid residues that are found primarily in the flexible regions of collagen molecules.Localization of collagen types in regional segments of the fetal bovine aorta.Types I, III, and IV collagens were localized immunocytochemically in muscular and small arteries of fetal bovine tissues and in different regional segments of the aorta.

The distribution of these collagens was found to be unique, not only with respect to collagen type and fiber orientation but also to the specific region of the vessel being examined. Collagen types I, III, and IV often codistribute in the intimal and medial regions of blood vessels, whereas types I and III show selective association in fibers with varied morphology in the adventitial layer. Specific segments of the aorta (proximal thoracic versus distal abdominal) were examined to determine the relative distribution and morphologic presentation of the collagens. In the ascending region of the aorta proximal to the heart, the types I, III, and IV collagen colocalized in the intimal and medial layers. Types I and III collagen predominated in the relatively small adventitial layer, whereas type IV collagen was found only in association with the media of small blood vessels and capillaries in this layer. In the descending thoracic region of the aorta distal to the arch, types I and IV collagens were distributed throughout the intimal and medial layers, whereas type III collagen localization was variable depending on the antibody used for detection. The adventitia stained predominantly for type III collagen that was distinctly organized in folded arrays of fibers.

These same fibers stained less intensely with antibody to type I collagen. The abdominal aorta near the common iliacs stained in a fashion similar to that of muscular arteries of the organs and tissues examined, i.e., types I and IV collagen were found in the intimal and medial layers, whereas type III collagen localized heavily to the adventitial layer, with differential staining in the intima and media depending on the antibody used. Additional staining of the adventitial region of the abdominal aorta with type I and type IV collagen antibodies was the same as in the proximal and descending regions. Since the abdominal aorta sustains decreased levels of pulsatile distension compared with the ascending thoracic aorta, type III collagen distribution and its association with other matrix components may be important in regulating the range of distensibility of the 5928.  Seebio ergo mushroom :129-51.Fine structure of collagens and their relation to glucosaminoglycans (GAG).Type XX Collagen Is Elevated in Circulation of Patients with Solid Tumors.University of Copenhagen, 2200 Copenhagen, Denmark.In the tumor microenvironment, the extracellular matrix (ECM) has been recognized as an important part of cancer development.  Get it now  are the 28 types of collagens, each with a unique function in tissue architecture. Type XX collagen, however, is poorly characterized, and little is known about its involvement in cancer.

We developed an ELISA quantifying type XX collagen, named PRO-C20, using a monoclonal antibody raised against the C-terminus. PRO-C20 and PRO-C1, an ELISA targeting the N-terminal pro-peptide of type I collagen, was measured in sera of 219 patients with various solid cancer types and compared to sera levels of 33 healthy controls. PRO-C20 was subsequently measured in a separate cohort comprising 36 patients with pancreatic ductal adenocarcinoma (PDAC) and compared to 20 healthy controls and 11 patients with chronic pancreatitis. PRO-C20 was significantly elevated in all cancers tested: bladder, breast, colorectal, head and neck, kidney, lung, melanoma, ovarian, pancreatic, prostate, and stomach cancer (p < 01−p < 0001). PRO-C1 was only elevated in patients with ovarian cancer. PRO-C20 could discriminate between patients and healthy controls with AUROC values ranging from 06 to 02.