scholarly journals Existence and Features of the Myodural Bridge in Gentoo Penguins: a morphological study

2020 ◽  
Author(s):  
Cheng Chen ◽  
Sheng-bo Yu ◽  
Yan-yan Chi ◽  
Guang-yuan Tan ◽  
Bao-cheng Yan ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Dura Mater ◽  
Type I Collagen ◽  
Morphological Characteristics ◽  
Gentoo Penguin ◽  
Type I ◽  
Marine Birds ◽  
Dense Connective Tissue ◽  
Myodural Bridge ◽  
Histological Staining

AbstractRecent studies have evidenced that the anatomical structure now known as the myodural bridge (MDB) connects the suboccipital musculature to the cervical spinal dura mater (SDM). In humans, the MDB passes through both the posterior atlanto-occipital and the posterior atlanto-axial interspaces. The present authors suggest that the MDB has important physiological functions in humans. The existence of the MDB in various mammals, including flying birds (Rock pigeons and Gallus domesticus) has been previously validated. Gentoo penguins are marine birds, able to make 450 dives per day, reaching depths of up to 660 feet. Gentoo penguins are also the world’s fastest diving birds. The present study was therefore carried out to investigate the existence and characteristics of the MDB in Gentoo penguin (Pygoscelis papua), a non-flying, marine bird that can dive. While foraging, this penguin is able to reach speeds of up to 22 miles per hour. For this study, six Gentoo penguin specimens were dissected to observe the existence and composition of their MDB. Histological staining was also performed to analyze the anatomic relationships and characteristic of the MDB in the Gentoo penguin. In this study, it was found that the suboccipital musculature in the Gentoo penguin consists of the rectus capitis dorsalis minor (RCDmi) muscle and rectus capitis dorsalis major (RCDma) muscle. Dense connective tissue fibers were observed connecting these two suboccipital muscles to the spinal dura mater (SDM). This dense connective tissue bridge consists of primarily type I collagen fibers. Thus, this penguin’s MDB appears to be analogous to the MDB previously observed in humans. The present study evidences that the MDB not only exists in penguins but it also has unique features that distinguishes it from that of flying birds. Thus, this study advances the understanding of the morphological characteristics of the MDB in flightless, marine birds.

scholarly journals Existence and features of the myodural bridge in Gentoo penguins: A morphological study

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0244774
Author(s):  
Cheng Chen ◽  
Sheng-bo Yu ◽  
Yan-yan Chi ◽  
Guang-yuan Tan ◽  
Bao-cheng Yan ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Dura Mater ◽  
Type I Collagen ◽  
Morphological Characteristics ◽  
Gentoo Penguin ◽  
Type I ◽  
Marine Birds ◽  
Dense Connective Tissue ◽  
Myodural Bridge ◽  
Histological Staining

Recent studies have evidenced that the anatomical structure now known as the myodural bridge (MDB) connects the suboccipital musculature to the cervical spinal dura mater (SDM). In humans, the MDB passes through both the posterior atlanto-occipital and the posterior atlanto-axial interspaces. The existence of the MDB in various mammals, including flying birds (Rock pigeons and Gallus domesticus) has been previously validated. Gentoo penguins are marine birds, able to make 450 dives per day, reaching depths of up to 660 feet. While foraging, this penguin is able to reach speeds of up to 22 miles per hour. Gentoo penguins are also the world’s fastest diving birds. The present study was therefore carried out to investigate the existence and characteristics of the MDB in Gentoo penguin (Pygoscelis papua), a non-flying, marine bird that can dive. For this study, six Gentoo penguin specimens were dissected to observe the existence and composition of their MDB. Histological staining was also performed to analyze the anatomic relationships and characteristic of the MDB in the Gentoo penguin. In this study, it was found that the suboccipital musculature in the Gentoo penguin consists of the rectus capitis dorsalis minor (RCDmi) muscle and rectus capitis dorsalis major (RCDma) muscle. Dense connective tissue fibers were observed connecting these two suboccipital muscles to the spinal dura mater (SDM). This dense connective tissue bridge consists of primarily type I collagen fibers. Thus, this penguin’s MDB appears to be analogous to the MDB previously observed in humans. The present study evidences that the MDB not only exists in penguins but it also has unique features that distinguishes it from that of flying birds. Thus, this study advances the understanding of the morphological characteristics of the MDB in flightless, marine birds.

scholarly journals ΕGFR/ERβ-Mediated Cell Morphology and Invasion Capacity Are Associated with Matrix Culture Substrates in Breast Cancer

Cells ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 2256
Author(s):  
Konstantina Kyriakopoulou ◽  
Eirini Riti ◽  
Zoi Piperigkou ◽  
Konstantina Koutroumanou Sarri ◽  
Heba Bassiony ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cell Morphology ◽  
Breast Cancer Cells ◽  
Type I Collagen ◽  
Morphological Characteristics ◽  
Migration And Invasion ◽  
Type I ◽  
Egfr Inhibition ◽  
The Impact

Breast cancer accounts for almost one in four cancer diagnoses in women. Studies in breast cancer patients have identified several molecular markers, indicators of aggressiveness, which help toward more individual therapeutic approaches. In triple-negative breast cancer (TNBC), epidermal growth factor receptor (EGFR) overexpression is associated with increased metastatic potential and worst survival rates. Specifically, abnormal EGFR activation leads to altered matrix metalloproteinases’ (MMPs) expression and, hence, extracellular matrix (ECM) degradation, resulting in induced migration and invasion. The use of matrix substrates for cell culture gives the opportunity to mimic the natural growth conditions of the cells and their microenvironment, as well as cell–cell and cell–matrix interactions. The aim of this study was to evaluate the impact of EGFR inhibition, estrogen receptor beta (ERβ) and different matrix substrates [type I collagen and fibronectin (FN)] on the functional properties, expression of MMPs and cell morphology of ERβ-positive TNBC cells and shERβ ones. Our results highlight EGFR as a crucial regulator of the expression and activity levels of MMPs, while ERβ emerges as a mediator of MMP7 and MT1-MMP expression. In addition, the EGFR/ERβ axis impacts the adhesion and invasion potential of breast cancer cells on collagen type I. Images obtained by scanning electron microscope (SEM) from cultures on the different matrix substrates revealed novel observations regarding various structures of breast cancer cells (filopodia, extravesicles, tunneling nanotubes, etc.). Moreover, the significant contribution of EGFR and ERβ in the morphological characteristics of these cells is also demonstrated, hence highlighting the possibility of dual pharmacological targeting.

scholarly journals Molecular Mechanism for Connective Tissue Destruction by Dipeptidyl Aminopeptidase IV Produced by the Periodontal Pathogen Porphyromonas gingivalis

2005 ◽  
Vol 73 (5) ◽  
pp. 2655-2664 ◽  
Author(s):  
Yumi Kumagai ◽  
Hisao Yagishita ◽  
Ayako Yajima ◽  
Tatsuya Okamoto ◽  
Kiyoshi Konishi
Keyword(s):  
Connective Tissue ◽  
Molecular Mechanism ◽  
Porphyromonas Gingivalis ◽  
Type I Collagen ◽  
Plasmid Vector ◽  
Periodontal Pathogen ◽  
Matrix Metalloproteinase 2 ◽  
Type I ◽  
Tissue Destruction ◽  
Dipeptidyl Aminopeptidase

ABSTRACT Porphyromonas gingivalis is a pathogen associated with adult periodontitis. It produces dipeptidyl aminopeptidase IV (DPPIV), which may act as a virulence factor by contributing to the degradation of connective tissue. We investigated the molecular mechanism by which DPPIV contributes to the destruction of connective tissue. DPPIV itself did not show gelatinase or collagenase activity toward human type I collagen, but it promoted the activity of the host-derived matrix metalloproteinase 2 (MMP-2) (gelatinase) and MMP-1 (collagenase). DPPIV bound to fibronectin and mediated the adhesion of P. gingivalis to fibronectin. Mutant DPPIV with catalytic Ser mutagenized to Ala (DPPSA) did not accelerate the degradation of collagen and gelatin by MMPs but retained fibronectin-binding activity. The adhesion of human gingival fibroblasts and NIH 3T3 cells to fibronectin was inhibited by DPPIV. Strain 4351ADPPSA exhibited an intermediate level of virulence in mice, between that of the strain expressing wild-type DPPIV (4351ADPP) and that of the strain harboring only the plasmid vector (4351AVEC). It is suggested that both activity promoting the degradation of collagen and gelatin and binding to fibronectin are required for full virulence. These results reveal novel biological functions of DPPIV and suggest a pathological role in the progression of periodontitis.

Polarized Light Microscopy for Analyzing Tissue Mechanics During In Vitro Acupuncture

2008 ◽  
Author(s):  
Lowell Taylor Edgar ◽  
Margaret Julias ◽  
David I. Shreiber ◽  
Helen M. Buettner
Keyword(s):  
Connective Tissue ◽  
Light Microscopy ◽  
Type I Collagen ◽  
Polarized Light ◽  
Tissue Mechanics ◽  
Polarized Light Microscopy ◽  
Tissue Response ◽  
Type I ◽  
Collagen Gels

Acupuncture is a traditional therapy originating in China almost 2000 years ago. Acupuncture has slowly been growing in popularity in the West, and clinical evidence has shown the potential for acupuncture as a low-cost ‘alternative’ therapy for an assortment of ailments [1]. The practice of acupuncture involves inserting fine needles into the skin followed by needle manipulation, usually by rotation. Recent studies by Langevin et al demonstrate that this rotation causes the subcutaneous connective tissue to couple to and wind around the needle [2–4], which suggests that mechanotransduction in the connective tissue might play a role in the therapeutic mechanisms that underlay acupuncture [2, 3]. To begin to decompose and quantify this complex mechanism at the tissue level in a controlled setting, we have simulated acupuncture in type I collagen gels in vitro, and have developed algorithms to quantify the tissue response following imaging with polarized light microscopy (PLM).

Identification of Genes Differentially Regulated in Rat Alveolar Bone Wound Healing by Subtractive Hybridization

2004 ◽  
Vol 83 (7) ◽  
pp. 546-551 ◽  
Author(s):  
T. Ohira ◽  
F. Myokai ◽  
N. Shiomi ◽  
K. Yamashiro ◽  
T. Yamamoto ◽  
...  
Keyword(s):  
Wound Healing ◽  
Connective Tissue ◽  
Type I Collagen ◽  
Alveolar Bone ◽  
Subtractive Hybridization ◽  
Tissue Structure ◽  
Type I ◽  
Expression Of Genes ◽  
Periodontal Healing ◽  
Connective Tissue Structure

Periodontal healing requires the participation of regulatory molecules, cells, and scaffold or matrix. Here, we hypothesized that a certain set of genes is expressed in alveolar bone wound healing. Reciprocal subtraction gave 400 clones from the injured alveolar bone of Wistar rats. Identification of 34 genes and analysis of their expression in injured tissue revealed several clusters of unique gene regulation patterns, including the up-regulation at 1 wk of cytochrome c oxidase regulating electron transfer and energy metabolism, presumably occurring at the site of inflammation; up-regulation at 2.5 wks of pro-α-2 type I collagen involving the formation of a connective tissue structure; and up-regulation at 1 and 2 wks and down-regulation at 2.5 and 4 wks of ubiquitin carboxyl-terminal hydrolase l3 involving cell cycle, DNA repair, and stress response. The differential expression of genes may be associated with the processes of inflammation, wound contraction, and formation of a connective tissue structure.

Pivotal role of connective tissue growth factor in lung fibrosis: MAPK-dependent transcriptional activation of type I collagen

2009 ◽  
Vol 60 (7) ◽  
pp. 2142-2155 ◽  
Author(s):  
Markella Ponticos ◽  
Alan M. Holmes ◽  
Xu Shi-Wen ◽  
Patricia Leoni ◽  
Korsa Khan ◽  
...  
Keyword(s):  
Growth Factor ◽  
Connective Tissue ◽  
Connective Tissue Growth Factor ◽  
Transcriptional Activation ◽  
Lung Fibrosis ◽  
Type I Collagen ◽  
Tissue Growth ◽  
Pivotal Role ◽  
Type I

scholarly journals Connective tissue, glial and neuronal expressions in testis of the African giant rat (Cricetomys gambianus)

2017 ◽  
Vol 34 (03) ◽  
pp. 186-193
Author(s):  
T. Falade ◽  
M. Olude ◽  
O. Mustapha ◽  
E. Mbajiorgu ◽  
A. Ihunwo ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Type I Collagen ◽  
Collagen Type ◽  
Neuronal Cells ◽  
Collagen Type I ◽  
Type I ◽  
Collagen Type Iii ◽  
Neuronal Markers ◽  
Type Iii ◽  
African Giant Rat

Abstract Introduction: This study was carried out to investigate the expression of connective tissue (Collagens I and III), glia and neuronal markers in the testis of the African giant rat using histology and immunohistochemistry techniques. Materials and Methods: Eight (8) apparently healthy wild male African giant rats were used for this experiment, divided into 2 groups (juvenile and adult) of 4 animals each. The testes were harvested following intracardial perfusion of the rats and histology was performed using Haematoxylin-Eosin stain and Mallory-Heideinhain rapid one- step staining for connective tissue. Immunohistochemical identification was achieved using the following antibodies: anti-collagen type I, anti-collagen type III, anti-glial fibrillary acidic protein and anti-p75 nerve growth factor for the expression of collagen type I, collagen type III, astrocyte-like cell and neuronal cells respectively. Photomicrography was achieved using Axioskop® microscope and quantitative data were analyzed using student t-test. Results: The cyto-architecture of the testis was typical in the African giant rat. The connective tissue expressed in the juvenile and adult group, signaling of glial-like cells were seen in the perivascular region across the experimental groups. Immuno-localization of neuronal cells were seen in the interstitial spaces across all the groups, but with more expressions in the juvenile. Conclusion: This work has provided a clear description of the expression of connective tissue, neuronal and glial cells in the testis of the African giant rat and their possible relationships across juvenile and adult groups.

Reconstruction of a Hard Connective Tissue Utilizing a Pressed Silk Sheet and Type-I Collagen as the Scaffold for Fibroblasts

2007 ◽  
Vol 13 (6) ◽  
pp. 1357-1366 ◽  
Author(s):  
Toshiaki Takezawa ◽  
Katsuyuki Ozaki ◽  
Chiyuki Takabayashi
Keyword(s):  
Connective Tissue ◽  
Type I Collagen ◽  
Type I
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