Search results for " Collage"
showing 10 items of 161 documents
Specifications and validation of the ACMG/AMP criteria for clinical interpretation of sequence variants in collagen genes associated with joint hyper…
2023
Deleterious variants in collagen genes are the most common cause of hereditary connective tissue disorders (HCTD). Adaptations of the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) criteria are still lacking. A multidisciplinary team was set up for developing specifications of the ACMG/AMP criteria for COL1A1, COL1A2, COL2A1, COL3A1, COL5A1, COL5A2, COL11A1, COL11A2 and COL12A1, associated with various forms of HCTD featuring joint hypermobility, which is becoming one of the most common reasons of referral for molecular testing in this field. Such specifications were validated against 209 variants, and resulted effective for classifying as p…
Biocompatibility of various collagen membranes in cultures of human PDL fibroblasts and human osteoblast-like cells
2004
The aim of the present study was to evaluate the biocompatibility of differently cross-linked collagen membranes in cultures of human PDL fibroblasts and human osteoblast-like cells. Four collagen membranes [BioGide (BG), BioMend (BM), Ossix (OS) and TutoDent (TD)] were tested. Cells plated on culture dishes (CD) served as positive controls. Six specimens of each membrane were incubated with (1) human PDL fibroblasts [2 x 10(4) cells] (n=24), and (2) human osteoblast-like cells (SaOs-2) [2 x 10(4) cells] (n=24) under standardized conditions. After 7 days, adherent cells were stained with hematoxylin and counted using a reflected light microscope and the cell density per square millimeter wa…
Expression of host defense scavenger receptors in spondylarthropathy
2001
Objective Reactive arthritis (ReA) is postulated to be caused by a defective host defense against gram-negative bacteria. HLA–B27 could play a role in this process, but does not account for the many HLA–B27 negative patients. The objective of this study was to test the expression of 3 macrophage scavenger receptors (SRs) that are responsible for innate immunity against gram-negative bacteria: SR class A type I (SR-AI), SR-AII, and the macrophage receptor with collagenous structure (MARCO). We postulate that defects in such receptors might also contribute to the host risk factors that increase the predisposition to ReA and perhaps other subtypes of spondylarthropathy (SpA). Methods Periphera…
CD10 and HHF35 actin in the differential diagnosis between Collagenous Spherulosis and Adenoid-Cystic Carcinoma of the breast
2012
Collagenous Spherulosis (CS) and Adenoid-Cystic Carcinoma (AdCC) of the breast consist of cribriform proliferations of epithelial and myoepithelial cells with an immunophenotypic overlap of some myoepithelial markers, such as p63 and smooth muscle actin (SMA). To our knowledge, CD10 and HHF35 actin have not been assessed in the differential diagnosis of these two breast lesions. We performed an immunohistochemical study on 6 cases of CS and 9 cases of AdCC. We found CD10, muscle-specific actin (HHF35), Estrogen and Progesterone receptors (ER and PR) to be strongly expressed in CS, but not in AdCC; C-kit was diffusely positive in AdCC and scanty in CS; SMA, p63 and Cytokeratine 5/6 (CK5/6) w…
The relationship between transient elastography and histological collagen proportionate area for assessing fibrosis in chronic viral hepatitis
2012
Collagen proportionate area (CPA) has a better correlation with hepatic venous pressure gradient (HVPG) than with Ishak stage. Liver stiffness measurement (LSM) is proposed as non invasive marker of portal hypertension/disease progression. Our aim was to compare LSM and CPA with Ishak staging in chronic viral hepatitis, and HVPG in HCV hepatitis after transplantation. One hundred and sixty-nine consecutive patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections pre/post liver transplantation (LT), had a liver biopsy combined with LSM (transient elastography), CPA (biopsies stained with Sirius Red and evaluated by digital image analysis and expressed as CPA) and H…
Computer-assisted image analysis of liver collagen: relationship to Ishak scoring and hepatic venous pressure gradient.
2009
Histopathological scoring of disease stage uses descriptive categories without measuring the amount of fibrosis. Collagen, the major component of fibrous tissue, can be quantified by computer-assisted digital image analysis (DIA) using histological sections. We determined relationships between DIA, Ishak stage, and hepatic venous pressure gradient (HVPG) reflecting severity of fibrosis. One hundred fifteen patients with hepatitis C virus (HCV) who had undergone transplantation had 250 consecutive transjugular liver biopsies combined with HVPG (median length, 22 mm; median total portal tracts, 12), evaluated using the Ishak system and stained with Sirus red for DIA. Liver collagen was expres…
Biomechanical properties of oesophagus wall under loading
2003
In this investigation, firstly, the biomechanical properties of different parts of oesophagus were determined. Oesophagus stress and strain are the greatest in the cervical part for all age groups. The human oesophagus deforms unevenly, depending on the direction of load in relation to the organ's axis, it exhibits anisotropical behaviour. With the age the values of mechanical parameters of the oesophagus wall reduce, in particular beginning from 45 years of age, but the modulus of elasticity increases. Biomechanical properties of the oesophagus depend on the architecture of its structure. By loading the organ in the circumferential direction, microfibrilae rupture and deformation of the mu…
A custom image-based analysis tool for quantifying elastin and collagen micro-architecture in the wall of the human aorta from multi-photon microscopy
2014
The aorta possesses a micro-architecture that imparts and supports a high degree of compliance and mechanical strength. Alteration of the quantity and/or arrangement of the main load-bearing components of this micro-architecture - the elastin and collagen fibers - leads to mechanical, and hence functional, changes associated with aortic disease and aging. Therefore, in the future, the ability to rigorously characterize the wall fiber micro-architecture could provide insight into the complicated mechanisms of aortic wall remodeling in aging and disease. Elastin and collagen fibers can be observed using state-of-the-art multi-photon microscopy. Image-analysis algorithms have been effective at…
Lower strength of the human posterior patellar tendon seems unrelated to mature collagen cross-linking and fibril morphology
2009
The human patellar tendon is frequently affected by tendinopathy, but the etiology of the condition is not established, although differential loading of the anterior and posterior tendon may be associated with the condition. We hypothesized that changes in fibril morphology and collagen cross-linking would parallel differences in material strength between the anterior and posterior tendon. Tendon fascicles were obtained from elective ACL surgery patients and tested micromechanically. Transmission electron microscopy was used to assess fibril morphology, and collagen cross-linking was determined by HPLC and calorimetry. Anterior fascicles were markedly stronger (peak stress: 54.3 ± 21.2 vs.…
Characterization of collagenase 3 (matrix metalloproteinase 13) messenger RNA expression in the synovial membrane and synovial fibroblasts of patient…
1999
Objective To study the localization and cell type–specific expression of collagenase 3 messenger RNA (mRNA) in the synovial membrane, its regulation in primary synovial fibroblasts, and the correlation with systemic markers of inflammation and radiographic damage in rheumatoid arthritis (RA). Methods The expression of collagenase 3 mRNA was characterized by Northern blot analysis, reverse transcriptase–polymerase chain reaction, and in situ hybridization. Immunohistochemical detection of cell type–specific antigens was used in combination with in situ hybridization of collagenase 3 mRNA to characterize the cellular origin of collagenase 3 mRNA expression. Results Collagenase 3 mRNA was dete…