Search results for "Filament"
showing 10 items of 405 documents
Complexity of expression of intermediate filament proteins, including glial filament protein, in endometrial and ovarian adenocarcinomas
1991
The expression patterns of intermediate filament proteins of primary and metastatic endometrial (n = 18) and ovarian (n = 24) adenocarcinomas were analyzed by immunocytochemistry using a panel of specific antibodies and by gel electrophoresis of cytoskeletal preparations, followed by immunoblotting. All cells of all endometrial adenocarcinomas studied contained the "simple epithelial"-type cytokeratins (CKs) 8, 18, and (mostly) 19, with variable numbers of cells also positive for CK 7 and vimentin. In addition, most of these tumors contained individual cells or groups of cells that were positive for the stratification-related CKs 4, 5, 6, 13, 14, and 17. The latter CKs were often associated…
Desmin-related myopathies
1997
Desmin-related myopathies are marked by accumulation of desmin, which is often familial and associated with cardiomyopathy. When multifocal this excess is characterized by inclusions such as cytoplasmic or spheroid bodies, when disseminated the excess is called granulofilamentous material. Excess of desmin might represent an abnormal type of protein metabolism.
Mucoepidermoid mammary carcinoma. Immunohistochemical and biochemical analyses of intermediate filaments.
1989
The histological features of mucoepidermoid mammary carcinomas (MMCs) are presented, and criteria for distinguishing these tumours from squamous epithelial metaplasia in other mammary carcinomas are considered. Immunohistochemical and gel-electrophoretic analyses of the intermediate-filament proteins in one MMC case revealed a complex pattern of cytokeratin polypeptide expression. The simple-epithelium-type cytokeratins 7, 8, 18, and 19 were detected mainly in nonsquamous (including mucinous) cells, while the stratified-epithelium-type cytokeratins 5, 6, 14, 16, and 17 were present in squamous cells. However, in both the nonsquamous and squamous regions of the tumour, cytokeratins of the "r…
Cytoskeletal Heterogeneity of an Epithelioid Sarcoma with Expression of Vimentin, Cytokeratins, and Neurofilaments
1990
We studied an unusual sarcoma with morphologic features diagnostic of epithelioid sarcoma by conventional light microscopy, transmission electron microscopy, and immunohistochemistry. The primary tumor, which was located in the deep soft tissues of the buttock of a 32-year-old woman, and its metastases to lymph nodes, liver, and lung were available for investigation. The histomorphological and ultrastructural appearance of the primary tumor and its metastatic deposits were typical of epithelioid sarcoma. Immunohistochemistry revealed a strong and uniform reactivity for vimentin in both the primary tumor and its metastases. In contrast, a marked cytoskeletal heterogeneity became evident for …
Immunohistochemical localization of filaggrin in benign, premalignant and malignant cervical tissue.
1994
Epithelial distribution of filaggrin, a histidine-rich protein related to squamous terminal differentiation, was investigated in 87 cervical biopsies using an avidin-biotin-peroxidase technique with a monoclonal anti-human filaggrin antibody (AKH1). Normal squamous cervical epithelium exhibited a positive homogeneous immunoperoxidase stain in the upper parabasal, intermediate and superficial cell layers. Similar findings were obtained in cervical condylomas, although full-thickness staining was observed in 35.7% of the cases (P < 0.001). Filaggrin expression in CIN was inversely related to the severity of the lesion (P < 0.001). An irregular staining pattern was present in most high-grade C…
Cytokeratin 20 Is a General Marker of Cutaneous Merkel Cells While Certain Neuronal Proteins Are Absent
1995
Merkel cells are difficult to identify in tissue sections. Previous studies have used cytokeratins (CK) 8, 18, and 19 as histologic markers of Merkel cells. However, these CKs are also expressed in some outer root sheath keratinocytes and some early fetal epidermal cells and thus are not truly specific of Merkel cells in general. Using selective antibodies against a newly described CK, number 20--originally found in intestinal epithelium and Merkel cell carcinomas--in comparison to a key protein of neuroendocrine cells, chromogranin A, we established CK 20 as a specific Merkel cell marker in skin of humans, pigs, and mice. CK 20 seems to be an even more general and sensitive Merkel cell mar…
Changes of Expression of Intermediate Filament Proteins During Ontogenesis of Eccrine Sweat Glands
1992
The intermediate filament expression in fetal and adult human eccrine sweat glands was studied by immunoperoxidase microscopy performed on cryostat sections using monoclonal antibodies against various cytokeratins (CK), vimentin, and actin. In palmar skin of 14-week-old fetuses, the early dermal cords showed a primitive CK pattern similar to that of epidermal basal cells. From week 15 on (distal finger skin), inner cells of the proximal (ductal) portion of the glandular anlagen expressed CK 1/10/11 and 19 (markers of adult eccrine ductal luminal cells). In addition, CK 4 was expressed in ductal luminal cells mainly in the fetal period. In the distal portion of the sweat gland anlagen the in…
Fetal akinesia caused by a novel actin filament aggregate myopathy skeletal muscle actin gene (ACTA1) mutation.
2010
We report a female newborn, diagnosed with fetal akinesia in utero, who died one hour after birth. Post-mortem muscle biopsy demonstrated actin-filament myopathy based on immunolabelling for sarcomeric actin, and large areas of filaments, without rod formation, ultrastructurally. Analysis of DNA extracted from the muscle disclosed a novel de novo heterozygous c.44G>A, GGC>GAC, 'p.Gly15Asp' mutation in the ACTA1 gene. Analysis of the location of the mutated amino-acid in the actin molecule suggests the mutation most likely causes abnormal nucleotide binding, and consequent pathological actin polymerization. This case emphasizes the association of fetal akinesia with actin-filament myopathy.
Anti-vimentin staining in muscle pathology
1993
The intermediate filaments of immature muscle fibres contain desmin and vimentin; vimentin is lacking in mature fibres. Regenerating fibres react with anti-vimentin antibodies and more intensely for desmin than mature fibres. The aim of the present study was to evaluate anti-vimentin staining for muscle pathology. Anti-vimentin-reactive fibres were found in 40 of 89 biopsies assessed. Fifteen patients with progressive destructive myopathy, infantile spinal muscular atrophy, clinically suspected Leigh's disease or unclassifiable congenital myopathy had between 1% and 95% vimentin-positive fibres. Less than 1% positive fibres were found in 25 patients with neuropathy with secondary myopathy o…