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Mesenchymal Tissues (mesenchymal + tissue)
Selected AbstractsExpression and regulation of mouse Mtsh1 during limb and branchial arch developmentDEVELOPMENTAL DYNAMICS, Issue 2 2001Qiaoming Long Abstract The mouse genome contains at least two genes, Mtsh1 and Mtsh2, related in sequence to the Drosophila homeotic gene teashirt (tsh). In this paper, we report the characterization of Mtsh1 expression in the developing branchial arches and forelimbs during mouse embryogenesis. Mtsh1 was found predominantly transcribed in the mesenchymal tissue of branchial arches and forelimbs. Surgical removal of the epithelium of both forelimb and branchial arch significantly decreased the expression of Mtsh1 in the mesenchymal cells of these tissues. Upon implantation of FGF8-soaked beads into arches and limbs, Mtsh1 transcription was up-regulated. In contrast, when BMP4-soaked beads were implanted, Mtsh1 expression was inhibited. Together, these results suggest that mouse Mtsh1 gene may be involved in the outgrowth of limbs and arches and may be functioning downstream of BMP and FGF signaling pathways. © 2001 Wiley-Liss, Inc. [source] Measurement of lesion area and volume by three-dimensional spoiled gradient-echo MR imaging in osteonecrosis of the femoral headJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2003Yuki Kishida Abstract The purpose of this investigation is to evaluate the diagnostic ability of three-dimensional spoiled gradient-echo (3D SPGR) magnetic resonance (MR) imaging in cases of osteonecrosis of the femoral head (ONFH), and to determine the accuracy of 3D SPGR imaging in area and volume measurement of ONFH. T1-weighted spin-echo (SE) and 3D SPGR imaging were performed on 20 femoral heads obtained from patients with ONFH. After MR imaging, the femoral heads were cut parallel to the imaging plane and were evaluated histologically. Areas and volumes of necrotic lesions were measured with a computer program and the deviation between MR images and anatomical measurements was evaluated. A low signal intensity band on 3D SPGR MR images was observed in all femoral heads and corresponded histologically to repaired marrow with viable fibrous mesenchymal tissue. The area proximate to the low band area coincided with the necrotic region. Both area and volume measurements by T1-weighted SE and 3D SPGR images showed a strong correlation to histological measurements. The discrepancies between histological and imaging results were minimal in 3D SPGR imaging, especially at the anterior and posterior portions of the femoral head. Three-dimensional SPGR imaging provides more accurate measurements of the area and volume of a necrotic lesion than T1-weighted SE imaging. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Hamartomatous endocervical polyp with heterologous mesenchymal tissuePATHOLOGY INTERNATIONAL, Issue 4 2001dvan Ilhan We present an endocervical polyp with heterologous elements. Although a few neoplastic cervical lesions with cartilaginous and adipocytic heterologous tissue have been reported, an endocervical polyp with heterologous cartilage and adipose tissue has not been reported before our case. The patient was a 33-year-old woman who presented with abnormal uterine bleeding. On physical examination, there were no remarkable findings other than a cervical polyp protruding into the cervical canal. The polyp was removed. Pathological examination revealed an endocervical polyp with typical epithelial features. The stroma of the polyp contained mature cartilage islands and adipose tissue. There were also many thick-walled vascular structures. Neither stromal periglandular condensation nor atypia was found. Mitotic figures were not observed. Arteriolar structures did not contain internal elastic lamina. In our opinion, these pathological findings are all consistent with a hamartomatous lesion rather than with a true neoplasm. [source] Matrix metalloproteinases mediate the dismantling of mesenchymal structures in the tadpole tail during thyroid hormone-induced tail resorptionDEVELOPMENTAL DYNAMICS, Issue 3 2002Jae-Chang Jung Abstract It has been suggested that a family of tissue remodelling enzymes called matrix metalloproteinases (MMPs) play a causal role in the process of tail resorption during thyroid hormone-induced metamorphosis of the anuran tadpole; however, this hypothesis has never been directly substantiated. We cloned two new Xenopus MMPs, gelatinase A (MMP-2) and MT3-MMP (MMP-16), and the MMP inhibitor TIMP-2. These clones were used along with several others to perform a comprehensive expression study. We show that all MMPs and TIMP-2 are dramatically induced in the resorbing tail during spontaneous metamorphosis and are spatially coexpressed, primarily in the remodelling mesenchymal tissues. By Northern blotting, we show that all the examined MMPs/TIMP-2 are also induced by treatment of organ-cultured tails with thyroid hormone (T3). Using the organ culture model, we provide the first direct evidence that MMPs are required for T3 -induced tail resorption by showing that a synthetic inhibitor of MMP activity/expression can specifically retard the resorption process. By gelatin zymography, we also show T3 induction of a fifth MMP, preliminarily identified as gelatinase B (GelB; MMP-9). Moreover, T3 not only induces MMP/TIMP expression but also MMP activation, and we provide evidence that TIMP-2 participates in the latter process. These findings suggest that MMPs and TIMPs act in concert to effect the dismantling of mesenchymal structures during T3 -induced metamorphic tadpole tail resorption. © 2002 Wiley-Liss, Inc. [source] Upregulation of plakophilin-2 and its acquisition to adherens junctions identifies a novel molecular ensemble of cell,cell-attachment characteristic for transformed mesenchymal cellsINTERNATIONAL JOURNAL OF CANCER, Issue 9 2009Steffen Rickelt Abstract In contrast to the desmosome-containing epithelial and carcinoma cells, normal and malignantly transformed cells derived from mesenchymal tissues and tumors are connected only by adherens junctions (AJs) containing N-cadherins and/or cadherin-11, anchored in a cytoplasmic plaque assembled by ,- and ,-catenin, plakoglobin, proteins p120 and p0071. Here, we report that the AJs of many malignantly transformed cell lines are characterized by the additional presence of plakophilin-2 (Pkp2), a protein hitherto known only as a major component of desmosomal plaques, i.e., AJs of epithelia and carcinomatous cells. This massive acquisition of Pkp2 and its integration into AJ plaques of a large number of transformed cell lines is demonstrated with biochemical and immunolocalization techniques. Upregulation of Pkp2 and its integration into AJs has also been noted in some soft tissue tumors insitu and some highly proliferative colonies of cultured mesenchymal stem cells. As Pkp2 has recently been identified as a functionally important major regulatory organizer in AJs and related junctions in epithelial cells and cardiomyocytes, we hypothesize that the integration of Pkp2 into AJs of "soft tissue tumor" cells also can serve functions in the upregulation of proliferation, the promotion of malignant growth in general as well as the close-packing of diverse kinds of cells and the metastatic behavior of such tumors. We propose to examine its presence in transformed mesenchymal cells and related tumors and to use it as an additional diagnostic criterion. © 2009 UICC [source] Stem cells in craniofacial and dental tissue engineeringORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 2 2005MV Risbud Abstract Authors ,, Risbud MV, Shapiro IM Mesenchymal stem cells (MSC) have been identified in a variety of adult tissues as a population of pluripotential self-renewing cells. Based on their adherence and colony forming properties, a small number of MSC can be isolated from most mesenchymal tissues as well as bone marrow. In the presence of one or more growth factors, these cells commit to lineages that lead to the formation of bone, cartilage, muscle, tendon and adipose tissue; recent studies indicate that stem cells for cementum, dentine and the periodontal ligament also exist. All of these cells can be expanded in vitro, and, embedded in a scaffold, inserted into defects to promote healing and tissue replacement. Increased understanding of the molecular mechanism directing lineage specification and morphogenesis is providing a rational approach for the regeneration of craniofacial tissues and oral structures. [source] Viscoelastic and Histologic Properties in Scarred Rabbit Vocal Folds After Mesenchymal Stem Cell Injection,THE LARYNGOSCOPE, Issue 7 2006S Hertegård MD Abstract Objective/Hypothesis: The aim of this study was to analyze the short-term viscoelastic and histologic properties of scarred rabbit vocal folds after injection of human mesenchymal stem cells (MSC) as well as the degree of MSC survival. Because MSCs are antiinflammatory and regenerate mesenchymal tissues, can MSC injection reduce vocal fold scarring after injury? Study Design: Twelve vocal folds from 10 New Zealand rabbits were scarred by a localized resection and injected with human MSC or saline. Eight vocal folds were left as controls. Material and Methods: After 4 weeks, 10 larynges were stained for histology and evaluation of the lamina propria thickness. Collagen type I content was analyzed from six rabbits. MSC survival was analyzed by fluorescent in situ hybridization staining from three rabbits. Viscoelasticity for 10 vocal folds was analyzed in a parallel-plate rheometer. Results: The rheometry on fresh-frozen samples showed decreased dynamic viscosity and lower elastic modulus (P < .01) in the scarred samples injected with MSC as compared with the untreated scarred group. Normal controls had lower dynamic viscosity and elastic modulus as compared with the scarred untreated and treated vocal folds (P < .01). Histologic analysis showed a higher content of collagen type 1 in the scarred samples as compared with the normal vocal folds and with the scarred folds treated with MSC. MSCs remained in all samples analyzed. Conclusions: The treated scarred vocal folds showed persistent MSC. Injection of scarred rabbit vocal folds with MSC rendered improved viscoelastic parameters and less signs of scarring expressed as collagen content in comparison to the untreated scarred vocal folds. [source] | |||||||||||||