Search results for "Collagen"
showing 10 items of 620 documents
Close of a fistula between the nose and the oral cavity using a new collagen matrix
2016
Endotrophin, a pro-peptide of Type VI collagen, is a biomarker of survival in cirrhotic patients with hepatocellular carcinoma
2021
Aim: Type VI collagen, is emerging as a signaling collagen originating from different types of fibroblasts. A specific fragment of Type VI collagen, the pro-peptide, is also known as the hormone endotrophin. We hypothesized that this fibroblast hormone would be of particular relevance in cancer types with a high amount of fibrosis activity, namely for outcome in hepatocellular carcinoma (HCC) cirrhotic patients. Patients & methods: Plasma C6M, PRO-C6 and alphafeto-protein (AFP) were assessed in 309 patients with mixed etiologies (hepatitis C, hepatitis B, alcohol and nonalcoholic fatty liver) diagnosed as cirrhotics, cirrhotics with HCC, noncirrhotics and healthy controls. Progression-f…
Integrin α2β1 Mediates Isoform-Specific Activation of p38 and Upregulation of Collagen Gene Transcription by a Mechanism Involving the α2 Cytoplasmic…
1999
Two collagen receptors, integrins alpha1beta1 and alpha2beta1, can regulate distinct functions in cells. Ligation of alpha1beta1, unlike alpha2beta1, has been shown to result in recruitment of Shc and activation of the Ras/ERK pathway. To identify the downstream signaling molecules activated by alpha2beta1 integrin, we have overexpressed wild-type alpha2, or chimeric alpha2 subunit with alpha1 integrin cytoplasmic domain in human osteosarcoma cells (Saos-2) lacking endogenous alpha2beta1. The chimeric alpha2/alpha1 chain formed a functional heterodimer with beta1. In contrast to alpha2/alpha1 chimera, forced expression of alpha2 integrin resulted in upregulation of alpha1 (I) collagen gene …
Extracellular matrix fiber microarchitecture is region-specific in bicuspid aortic valve-associated ascending aortopathy
2016
Abstract Objective Ascending thoracic aortic aneurysm (ATAA) in patients with bicuspid aortic valve (BAV) commonly dilate asymmetrically compared with patients with tricuspid aortic valve (TAV). This discrepancy in aneurysm geometry led us to hypothesize that microarchitectural differences underlie the observed asymmetric dilatation pattern. The purpose of this study was to characterize the microarchitectural distinctions of the extracellular matrix of the 2 phenotypes with a focus on the proportion of radially oriented elastin and collagen fibers in different circumferential aortic regions. Methods Aortic tissue rings were obtained just distal to the sinotubular junction from patients with…
Zebrafish Fins as a Model System for Skeletal Human Studies
2007
Recent studies on the morphogenesis of the fins ofDanio rerio(zebrafish) during development and regeneration suggest that a number of inductive signals involved in the process are similar to some of those that affect bone and cartilage differentiation in mammals and humans. Akimenko et al. (2002) has shown that bone morphogenetic protein-2b (BMP2b) is involved in the induction of dermal bone differentiation during fin regeneration. Many other groups have also shown that molecules from the transforming growth factor-beta superfamily (TGFβ), including BMP2, are effective in promoting chondrogenesis and osteogenesisin vivoin higher vertebrates, including humans. In the present study, we review…
First Chemosensor for Selective Detection and Quantification of L-4-Hydroxyproline in Collagen and Other Bio Samples.
2017
Amino pyridine-based rhodamine conjugate (APR) has been developed as a first chemosensor for selective detection and quantification of L-4-Hydroxyproline (Hyp). The “turn-on” fluorescence property of the chemosensor makes it unique for easy estimation of Hyp in collagen and biological samples. peerReviewed
Mandrel-less fabrication of biomimetic electrospun microfiber wires for tissue engineering applications
2021
This study introduces a novel mandrel-less electrodeposition method and a novel electrode prototypes useful for tissue engineering applications. More specifically, in this study a novel fabrication protocol to electrospun fibers-based chords, with length spanning from 2 cm to virtually no limitations on longitudinal length, is presented. For the first part of this study, Poly(ester urethane) urea (PEUU) was used to fabricate, by electrodeposition technique, continuous microfiber wires with controlled micro-architecture and tunable mechanics. A novel apparatus to process degradable or non-degradable polymers was used. Soft tissue injuries are common in daily clinical and surgical practice. O…
Behavior of Calcium Phosphate–Chitosan–Collagen Composite Coating on AISI 304 for Orthopedic Applications
2022
Calcium phosphate/chitosan/collagen composite coating on AISI 304 stainless steel was investigated. Coatings were realized by galvanic coupling that occurs without an external power supply because it begins with the coupling between two metals with different standard electrochemical potentials. The process consists of the co-deposition of the three components with the calcium phosphate crystals incorporated into the polymeric composite of chitosan and collagen. Physical-chemical characterizations of the samples were executed to evaluate morphology and chemical composition. Morphological analyses have shown that the surface of the stainless steel is covered by the deposit, which has a very r…
Optimization of a Biotechnological Process for Production and Purification of Two Recombinant Proteins: Col G and Col H
2017
Different strategies can be used for increasing production of heterologous recombinant proteins in Escherichia coli. Protein size is often critical for obtaining the best quantity/quality ratio of recombinant protein expression. This study focuses on two recombinant proteins; Class I and class II Collagenases, namely Col G and Col H. Their size is about 150 kDa each. We have developed a method to obtain high levels of cell growth and intracellular expression of each Collagenases in recombinant E. coli BL21(DE3). Batch and Fed-batch fermentation procedures have been performed. Results show that Fed-batch technique was most effective in obtaining the highest cell density for each recombinant …