Anchoring of Epithelia to Underlying Connective Tissue: Evidence of Frayed Ends of Collagen Fibrils Directly Merging with Meshwork of Lamina Densa

1994 ◽  
Keyword(s):  
Connective Tissue ◽  
Collagen Fibrils ◽  
Lamina Densa

Banded Structures in the Connective Tissue of Meningioma

1976 ◽  
Vol 34 ◽  
pp. 234-235
Author(s):  
C. N. Sun ◽  
H. J. White
Keyword(s):  
Connective Tissue ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Collagen Fibrils ◽  
Lead Citrate ◽  
Connective Tissues ◽  
Native Collagen ◽  
Routine Procedures

Previously, we have reported on extracellular cross-striated banded structures in human connective tissues of a variety of organs (1). Since then, more material has been examined and other techniques applied. Recently, we studied a fibrocytic meningioma of the falx. After the specimen was fixed in 4% buffered glutaraldehyde and post-fixed in 1% buffered osmium tetroxide, other routine procedures were followed for embedding in Epon 812. Sections were stained with uranyl acetate and lead citrate. There were numerous cross striated banded structures in aggregated bundle forms found in the connecfive tissue of the tumor. The banded material has a periodicity of about 450 Å and where it assumes a filamentous arrangement, appears to be about 800 Å in diameter. In comparison with the vicinal native collagen fibrils, the banded material Is sometimes about twice the diameter of native collagen.

Der Einfluß von D-Penicillamin auf den Gehalt einiger Organe an Spurenelementen sowie auf die mechanischen Eigenschaften von Kollagen / Trace Elements in Several Organs and Mechanical Properties of Collagen under the Influence of D-Penicillamin

1978 ◽  
Vol 33 (5-6) ◽  
pp. 346-358 ◽  
Author(s):  
H. Wesch ◽  
R. Jonak ◽  
H. Nemetschek-Gansler ◽  
H. Riedl ◽  
Th. Nemetschek
Keyword(s):  
Mechanical Properties ◽  
Trace Elements ◽  
Schiff Base ◽  
Connective Tissue ◽  
Functional Groups ◽  
Schiff Bases ◽  
Collagen Fibrils ◽  
Principal Effect ◽  
Tail Tendon ◽  
Cu Ions

Abstract The content of trace elements in several organs of rats under the influence of D-penicillamine (D-PA) was investigated by the neutronactivation-analysis. It could be shown an diminution of Cu, and Co under D-PA-treatment, the content of Fe, Mn, Rb and Zn was not influenced. The investigat­ ed organs didn’t show any submicroscopic alterations under D-PA. On isolated collagen fibrils of tail tendon was seen a significantly diminuition of E-moduls. In accordance with Siegel the principal effect of D-PA is thought to block the synthesis of functional groups from Schiff-base crosslink precursors but not to inhibit lysyloxidase by loss of Cu-ions of connective tissue. The thermostability of D-PA influenced fibrils is changed in stretched state only and will be due to the lack of crosslink Schiff-bases; where as the shrinking point of not stretched fibrils shows only aging dependent changes.

The Ultrastructure of the Connective Tissue Matrix is Significantly Improved Using Cryo-Fixation At High Pressure

2001 ◽  
Vol 7 (S2) ◽  
pp. 1194-1195
Author(s):  
D. Keene ◽  
S. Tufa
Keyword(s):  
High Pressure ◽  
Connective Tissue ◽  
Open Space ◽  
Freeze Substitution ◽  
Basement Membranes ◽  
Lamina Densa ◽  
Connective Tissue Matrix ◽  
Tissue Matrix ◽  
Processing Steps ◽  
Tissue Ultrastructure

The investigation of connective tissue ultrastructure has historically relied on chemical fixation to stabilize micro architecture. These fixatives are not effective in retaining many matrix molecules, including proteoglycans, and allow precipitation of many other components in subsequent processing steps. The result is a preponderance of open space between matrix components. Cells shrink considerably and a precipitation of molecules in highly concentrated regions leads to artifacts including the lamina lucida and lamina densa of basement membranes. Cryo-fixation at high pressure followed by freeze substitution seeks to immobilize tissue components within vitreous (non-crystalline) ice, which is later substituted with acetone at temperatures below the recrystalization temperature of water. Formation of large ice crystals during any part of the preparation protocol significantly distorts structure and can be recognized in the compound microscope. Recognition of smaller freezing artifacts, including microcrystalline ice, is imperative for interpretation of resulting images.

scholarly journals Factors Affecting IL-1-Mediated Collagen Metabolism By Fibroblasts and the Pathogenesis of Periodontal Disease: A Review of the Literature

1997 ◽  
Vol 8 (2) ◽  
pp. 217-236 ◽  
Author(s):  
Anne Havemose-Poulsen ◽  
Palle Holmstrup
Keyword(s):  
Extracellular Matrix ◽  
Connective Tissue ◽  
Periodontal Disease ◽  
Proteolytic Enzymes ◽  
Interleukin 1 ◽  
Collagen Fibrils ◽  
Review Of The Literature ◽  
Tissue Destruction ◽  
Factors Affecting ◽  
Extracellular Matrix Components

Fibroblasts have been studied extensively for their contribution to connective tissue destruction in diseases where the metabolism of extracellular matrix components plays an essential part in their pathogenesis. A considerable dissolution, especially of collagen fibrils, is a well-known characteristic of the periodontal ligament and the gingival connective tissue in microbial-induced periodontal disease. Fibroblasts, responsible for the assembly of the extracellular matrix, are capable of responding directly to oral microbial challenges or indirectly, following activation of the host immune response, and can alter the composition of connective tissue in several ways: synthesis of inflammatory mediators, their receptors and antagonists; fibroblast proliferation; collagen synthesis; phagocytosis of collagen fibrils; and synthesis of proteolytic enzymes, including matrix metalloproteinases and their corresponding inhibitors. The contributions of these cellular fibroblastic properties to the pathogenesis of periodontal disease are reviewed in the context of the cytokine, interleukin-1, as the inflammatory regulator.

Experimental study on an alternative to suturing the laparotomy wound with a mesh thread

2021 ◽  
Vol 29 (2) ◽  
pp. 277-286
Author(s):  
Andrey V. Fedoseev ◽  
Tatiyana M. Cherdantseva ◽  
Alexander S. Inyutin ◽  
Iliya B. Glukhovets ◽  
Sergey N. Lebedev ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Negative Impact ◽  
Collagen Fibrils ◽  
Wound Complications ◽  
Suture Materials ◽  
White Line ◽  
Fully Integrated ◽  
Longitudinal Orientation ◽  
Laparotomy Wound ◽  
Mesh Endoprosthesis

BACKGROUND: Incisional ventral hernias (IVH) in abdominal surgery remain relevant because the frequency of their formation after laparotomy reaches 10%30.7%. AIM: This study aimed to develop a method for the primary closure of a laparotomy wound via mesh endoprosthesis, which is superior to laparorrhaphy with traditional suture materials in terms of morphophysical properties. MATERIALS AND METHODS: Laparorrhaphy with a mesh thread was developed (Patent for invention RUS No 2714439 02/14/2020) as an alternative to preventive prosthetics with narrow indications to avoid herniation. An experimental work was conducted to investigate the wound process in the suture area on days 14 and 60 and determine the effectiveness and safety of the proposed method. RESULTS: Video laparoscopy data showed that no cases of adhesions were observed between the internal organs and the area of laparorrhaphy on days 14 and 60 of the postoperative period. Defects in the area of the application of sutures on the aponeurosis of the white line were absent. In the wound, the mesh thread fully integrated into the regenerating tissue, including at the site of the knot. The tissue also grew through the meshed cells. On day 14, the strength of the regenerating tissue with the sutured mesh thread was greater than that sutured without it (11.198 1.499, p 0.01). This finding was confirmed by the larger area of granulations and fibrosis in cases of mesh suture than that of the checkerwise-reinforcing suture, suture with a mesh thread, and suture with a strip of mesh endoprosthesis. Another peculiarity of the connective tissue newly formed in the area of the mesh endoprosthesis in the form of the mesh thread was that collagen fibrils were arranged concentrically. By contrast, the mesh strip had collagen fibrils arranged in a longitudinal orientation parallel to the endoprosthesis. On day 60 of the experiment, all the series showed signs of maturation of the connective tissue in the form of the predomination of fibrils in cellular elements and their compaction. The area of fibrosis and granulations still prevailed in cases of the mesh suture, where neocollagenogenesis in the cells of the endoprosthesis was more pronounced than that after the application of a reinforcing suture, a mesh thread, and a strip of mesh endoprosthesis. CONCLUSION: The absence of wound complications and negative impact on the surrounding tissues indicated the safety of using the mesh suture. The strengthened characteristics associated with the peculiarities of the wound process showed that the mesh suture was effective in preventing the occurrence of postoperative hernia. Therefore, this method could be used in clinical practice.

scholarly journals Recent Advances in the Pathophysiology of Musculocontractural Ehlers-Danlos Syndrome

Genes ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 43 ◽  
Author(s):  
Tomoki Kosho ◽  
Shuji Mizumoto ◽  
Takafumi Watanabe ◽  
Takahiro Yoshizawa ◽  
Noriko Miyake ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Dermatan Sulfate ◽  
Close Contact ◽  
Normal Skin ◽  
Collagen Fibrils ◽  
Ehlers Danlos Syndrome ◽  
Reticular Dermis ◽  
Pathogenic Variants ◽  
Recent Advances ◽  
Skin Stretching

Musculocontractural Ehlers–Danlos Syndome (mcEDS) is a type of EDS caused by biallelic pathogenic variants in the gene for carbohydrate sulfotransferase 14/dermatan 4-O-sulfotransferase 1 (CHST14/D4ST1, mcEDS-CHST14), or in the gene for dermatan sulfate epimerase (DSE, mcEDS-DSE). Thus far, 41 patients from 28 families with mcEDS-CHST14 and five patients from four families with mcEDS-DSE have been described in the literature. Clinical features comprise multisystem congenital malformations and progressive connective tissue fragility-related manifestations. This review outlines recent advances in understanding the pathophysiology of mcEDS. Pathogenic variants in CHST14 or DSE lead to reduced activities of relevant enzymes, resulting in a negligible amount of dermatan sulfate (DS) and an excessive amount of chondroitin sulfate. Connective tissue fragility is presumably attributable to a compositional change in the glycosaminoglycan chains of decorin, a major DS-proteoglycan in the skin that contributes to collagen fibril assembly. Collagen fibrils in affected skin are dispersed in the papillary to reticular dermis, whereas those in normal skin are regularly and tightly assembled. Glycosaminoglycan chains are linear in affected skin, stretching from the outer surface of collagen fibrils to adjacent fibrils; glycosaminoglycan chains are curved in normal skin, maintaining close contact with attached collagen fibrils. Homozygous (Chst14−/−) mice have been shown perinatal lethality, shorter fetal length and vessel-related placental abnormalities. Milder phenotypes in mcEDS-DSE might be related to a smaller fraction of decorin DS, potentially through residual DSE activity or compensation by DSE2 activity. These findings suggest critical roles of DS and DS-proteoglycans in the multisystem development and maintenance of connective tissues, and provide fundamental evidence to support future etiology-based therapies.

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