Search results for "differentiation"

Plexiform Atypical Spitz Tumor With Rosette-Like Giant Cells. A Histologic and Immunohistochemical Study on a Case Suggesting Ganglioneuroblastic Dif…

2018

Spitz nevi, atypical Spitz tumors and Spitzoid melanoma, the three clinicopathologic forms that constitute the spectrum of the Spitz-type melanocytic lesions, share a histologic picture characterized by large spindle and/or epithelioid ganglion-like cells, with various admixtures of multinucleate bizarre cells. This remarkable cytology has always been interpreted as an unusual, as well as unexplained form of atypia. We report a case of atypical Spitz tumor with Homer Wright-like rosettes, a feature characteristic of ganglioneuroblastic proliferation. Furthermore, the ganglion-like cells of the tumor showed basophilic punctuation in the cytoplasm, reminiscent of Nissl substance, and a few ce…

Perineural pattern of aggregation of cellular blue nevus: probable histoarchitectural reminiscence of histogenesis.

2008

A striking feature of cellular blue nevus consists in the presence, in its histologic picture, of numerous hypertrophic nerves and nerve-like figures, positive for histochemical and immunohistochemical methods for nerve fibers and myelin sheaths. These findings, first described in Masson's original article and repeatedly highlighted in the past for their possible histogenetic significance, are currently considered as merely coincidental. However, the thin conventional histologic sections, catching only short tracts of the nerves, preclude a correct observation of their route and do not allow us to verify if there is an architectural relationship between them and the nevus as a whole. With t…

Reply to “Primary cutaneous biphasic sarcomatoid basal cell carcinoma with myoepithelial carcinoma differentiation. Is it a new variant of sarcomatoi…

2020

Contribution of different bone marrow-derived cell types in endometrial regeneration using an irradiated murine model.

2015

Objective To study the involvement of seven types of bone marrow-derived cells (BMDCs) in the endometrial regeneration in mice after total body irradiation. Design Prospective experimental animal study. Setting University research laboratories. Animal(s) β-Actin-green fluorescent protein (GFP) transgenic C57BL/6-Tg (CAG-EGFP) and C57BL/6J female mice. Intervention(s) The BMDCs were isolated from CAG-EGFP mice: unfractionated bone marrow cells, hematopoietic progenitor cells, endothelial progenitor cells (EPCs), and mesenchymal stem cells (MSCs). In addition three murine GFP + cell lines were used: mouse Oct4 negative BMDC multipotent adult progenitor cells (mOct4 − BM-MAPCs), BMDC hypoblast…

Human Endometrial Side Population Cells Exhibit Genotypic, Phenotypic and Functional Features of Somatic Stem Cells

2010

During reproductive life, the human endometrium undergoes around 480 cycles of growth, breakdown and regeneration should pregnancy not be achieved. This outstanding regenerative capacity is the basis for women's cycling and its dysfunction may be involved in the etiology of pathological disorders. Therefore, the human endometrial tissue must rely on a remarkable endometrial somatic stem cells (SSC) population. Here we explore the hypothesis that human endometrial side population (SP) cells correspond to somatic stem cells. We isolated, identified and characterized the SP corresponding to the stromal and epithelial compartments using endometrial SP genes signature, immunophenotyping and char…

A novel in vitro model for the study of plaque development in atherosclerosis

2006

SummaryFor the study of atherogenesis in vitro, coculture systems have been devised, in which two or more cell types can be cultured in close contact to each other. Herein, we describe a novel in vitro model that aims at the simulation of the morphology ofa normal muscular artery allowing for the study of the initial events in atherosclerosis. Usinga modified fibrin gel as a scaffold for the coculture of endothelial cells (ECs) and smooth muscle cells (SMCs), we generated an autologous in vitro model with a multilayer growth of SMCs (intima-like structure) covered by an endothelium. The production of extracellular matrix (ECM) could be visualized histologically and verified by (i) ascorbic-…

Cytokeratin and Vimentin Expression in Primary and Recurrent Carcinoma of the Vulva

1996

Radical vulvectomy for the treatment of a vulvar carcinoma inevitably entails severe psychosexual consequences for the patients. Thus, for such tumors, reliable histological prognostic parameters are needed to allow; when appropriate, the use of less radical operative measures. One possible approach to this problem might be to examine tumors immunohistochemically for the presence of cytoskeletal components. To assess the utility of this method, we applied a panel of antibodies directed against cytokeratins (CKs) and vimentin to a groups of vulvar carcinomas (62 primary and 35 recurrent tumors) and examined the results for possible correlations with the course of disease and various clinical…

Norrie gene product is necessary for regression of hyaloid vessels.

2004

To investigate the nature and origin of the vitreous membranes in mice with knock-out of the Norrie gene product (ND mice).Eighty-two eyes of ND mice of different age groups (postnatal day [P]0-13 months) and 95 age-matched wild-type control mice were investigated. In vitreoretinal wholemounts and in sagittal sections, vessels and free cells were visualized by labeling for lectin. In addition, staining with a marker for macrophages (F4/80) and collagen XVIII/endostatin known to be involved in regression of hyaloid vessels was performed for light and electron microscopic investigations. Endostatin expression was confirmed by Western blot analysis.Wild-type controls showed the typical pattern…

The intraclonal and interclonal phenotypic heterogeneity in a rhabdomyosarcoma cell line with abortive imitation of embryonic myogenesis

1988

Three distinct subpopulations (A, B, C) derived from a dimethylbenzanthracene-induced rat rhabdomyosarcoma were established as permanent cell lines. Although the clonal nature of each of these subpopulations was confirmed by repeated recloning procedures, a striking intraclonal phenotypic heterogeneity was observed. By means of immunofluorescence microscopy and transmission electron microscopy, it could be shown that these subpopulations closely recapitulate stages of embryonic rhabdomyogenesis both in vitro and in vivo, but differ in their particular range of maximum differentiation. Embryonic rhabdomyogenesis is imitated most perfectly by subpopulation C, in which multinuclear myotubes ar…

The forgotten mathematical legacy of Peano

2019

International audience; The formulations that Peano gave to many mathematical notions at the end of the 19th century were so perfect and modern that they have become standard today. A formal language of logic that he created, enabled him to perceive mathematics with great precision and depth. He described mathematics axiomatically basing the reasoning exclusively on logical and set-theoretical primitive terms and properties, which was revolutionary at that time. Yet, numerous Peano’s contributions remain either unremembered or underestimated.