Search results for "intermediate filament"
showing 10 items of 103 documents
Desmin-related neuromuscular disorders
1995
Desmin, the intermediate filament protein of skeletal muscle fibers, cardiac myocytes, and certain smooth muscle cells, is a member of the cytoskeleton linking Z-bands with the plasmalemma and the nucleus. The pathology of desmin in human neuromuscular disorders is always marked by increased amounts, diffusely or focally. Desmin is highly expressed in immature muscle fibers, both during fetal life and regeneration as well as in certain congenital myopathies, together with vimentin. Desmin is also enriched in neonatal myotonic dystrophy and small fibers in infantile spinal muscular atrophy. Focal accretion of desmin may be twofold, in conjunction with certain inclusion bodies, cytoplasmic an…
121st ENMC International Workshop on Desmin and Protein Aggregate Myopathies. 7–9 November 2003, Naarden, The Netherlands
2004
The 121st European Neuromuscular Centre (ENMC)sponsored International Workshop on ‘DESMIN and Protein Aggregate Myopathies’, attended by 16 active participants from France, Germany, Poland, Spain, Sweden, the United Kingdom and the USA, was actually the fourth one in a row addressing the pathology of the muscle fibre intermediate filament desmin, its associated and similar diseases, all four [1–3] organized by Michel Fardeau and Hans H. Goebel. In his introduction, the chairman, Hans H. Goebel (Mainz), recorded the evolution of ‘Protein Aggregate Myopathies (PAM)’ which are marked by the accumulation of diverse proteins within muscle fibres as a morphologic hallmark in separate myopathies w…
Characterization of a Human Carcinosarcoma Cell Line of the Ovary Established after in Vivo Change of Histologic Differentiation
2001
Abstract Objectives. Cell lines are valuable in vitro models for clinical and basic research. Most ovarian cancer cell lines described are serous cystadenocarcinomas or poorly differentiated adenocarcinomas. The establishment of ovarian cancer cell lines with rare histologic differentiation is especially of interest. We describe the establishment of a carcinosarcoma cell line of the ovary after in vivo selection. Methods. The cell line OV-MZ-22 was established from a solid tumor mass in the upper abdomen. At the time of establishment, the patient underwent secondary debulking and was pretreated with six cycles of cis -platinum/epirubicin/cyclophosphamide. Features of the cell line studied i…
Merkel cells in ontogenesis of human nails
1993
Digital skin of human fetuses is known to contain a particularly high concentration of Merkel cells. Using antibodies against the simple epithelial cytokeratins (CK) 18 and 20, which are sensitive and specific Merkel cell markers, we studied immunohistochemically the main adnexal structure of digital skin, the nail anlage, in human fetuses (9-22 weeks of gestation) for the presence of Merkel cells. As early as week 9 some clustered Merkel cells were detected in the early matrix primordium. In specimens of week 12-15, abundant Merkel cells were found in the nail anlagen, particularly in the epithelium of the proximal nail-fold and the dorsal and ventral side of the apex region. In contrast, …
An immunohistochemical and biochemical study of cytokeratin polypeptides in a non-Paget type adenocarcinoma of the vulva
1988
SummaryThe intermediate filament composition was studied in a malignant neoplasm of the vulva in a 42 year old patient. The absence of vimentin excluded the diagnosis of malignant melanoma. Anaplastic squamous cell carcinoma could be excluded by the presence of glandular type cytokeratins numbers 7, 8, 18, 19 in the neoplastic cells. Intermediate filament typing did not support a diagnosis of epithelioid sarcoma. Since the typical epidermal involvement by tumour cells was lacking, Paget's disease was excluded. Metastatic adenocarcinoma was excluded by the lack of relevant clinical findings. It was concluded that the lesion represented an adenocarcinoma of the vulva of the non-Paget type mos…
Primary desminopathies.
2007
• Introduction • Desmin is an essential component of the extrasarcomeric cytoskeleton in striated muscle cells • Distal myopathy,cardiac arrhythmias,cardiomyopathy:classical criteria of primary desminopathies • Sub-sarcolemmal and cytoplasmic desmin-positive protein aggregates:the morphological hallmark of primary and secondary desminopathies • The spectrum of pathogenic desmin gene mutations • The molecular pathogenesis of primary desminopathies: some answers gained,but even more questions raised • Diagnostic work-up to distinguish primary from secondary desminopathies • Treatment and clinical management of primary desminopathy patients Abstract Mutations of the human desmin gene o…
OPLA scaffold, collagen I, and horse serum induce a higher degree of myogenic differentiation of adult rat cardiac stem cells
2009
In the last few years, a major goal of cardiac research has been to drive stem cell differentiation to replace damaged myocardium. Several research groups have attempted to differentiate potential cardiac stem cells (CSCs) using bi- or three-dimensional systems supplemented with growth factors or molecules acting as differentiating substances. We hypothesize that these systems failed to induce a complete differentiation because they lacked an architectural space. In the present study, we isolated a pool of small proliferating and fibroblast-like cells from adult rat myocardium. The phenotype of these cells was assessed and the characterized cells were cultured in a collagen I/OPLA scaffold …
Morphometry and comparative histology of sinus and atrioventricular nodes in humans and pigs and their relevance in the prevention of nodal arrhythmi…
2019
The cardiac conduction system is a network structure that allows the initiation and fast propagation of electrical impulses that trigger the electrical depolarization of the myocardial tissue. The purpose of this work is to study the histological and morphometric characteristics of the different components of the sinus and atrioventricular nodes in humans and pigs and their relationship with supraventricular arrhythmias. In this study, we describe the morphometry of the sinus and atrioventricular nodes of 10 adult humans and 10 pig hearts. A computerized morphometric study has been carried out, where we determined the number of cells that compose the nodes as well as different parameters re…
Focal adhesions are hotspots for keratin filament precursor formation
2006
Recent studies showed that keratin filament (KF) formation originates primarily from sites close to the actin-rich cell cortex. To further characterize these sites, we performed multicolor fluorescence imaging of living cells and found drastically increased KF assembly in regions of elevated actin turnover, i.e., in lamellipodia. Abundant KF precursors (KFPs) appeared within these areas at the distal tips of actin stress fibers, moving alongside the stress fibers until their integration into the peripheral KF network. The earliest KFPs were detected next to actin-anchoring focal adhesions (FAs) and were only seen after the establishment of FAs in emerging lamellipodia. Tight spatiotemporal …
De novo formation of cytokeratin filament networks originates from the cell cortex in A-431 cells
2001
Of the three major cytoskeletal filament systems, the intermediate filaments are the least understood. Since they differ fundamentally from the actin- and microtubulebased networks by their lack of polarity, it has remained a mystery how and where these principally endless filaments are formed. Using a recently established epithelial cell system in which fluorescently labeled intermediate filaments of the cytokeratin type can be monitored in living cells, we address these issues. By multidimensional time-lapse fluorescence microscopy, we examine de novo intermediate filament network formation from non-filamentous material at the end of mitosis and show that it mirrors disassembly. It is dem…