Search results for "Integument"
showing 10 items of 754 documents
Collagenase-3 (MMP-13) Enhances Remodeling of Three-Dimensional Collagen and Promotes Survival of Human Skin Fibroblasts
2006
Collagenase-3 (MMP-13) is a matrix metalloproteinase capable of cleaving a multitude of extracellular matrix proteins in addition to fibrillar collagens. Human MMP-13 is expressed by fibroblasts in chronic cutaneous ulcers, but not in normally healing adult skin wounds. However, MMP-13 is produced by fibroblasts in adult gingival and in fetal skin wounds characterized by rapid collagen remodeling and scarless healing. Here, we have examined the role of human MMP-13 in remodeling of three-dimensional (3D) collagenous matrix by primary adult human skin fibroblasts. The high level of human MMP-13 expression by fibroblasts achieved by adenoviral gene delivery resulted in potent enhancement of r…
Autofluorescence Imaging of the Skin Is an Objective Non-Invasive Technique for Diagnosing Pseudoxanthoma Elasticum
2021
Pseudoxanthoma elasticum (PXE) is a rare multisystemic autosomal recessive connective tissue disease. In most cases, skin manifestations of PXE are the first to develop, followed later by severe ocular and cardiovascular complications. In our present study, in addition to dermoscopy, we introduced novel techniques, autofluorescence (AF) and diffuse reflectance (DR) imaging for the assessment of affected skin sites of five PXE patients. PXE-affected skin areas in most skin sites showed a previously observed pattern upon dermoscopic examination. With the novel imaging, PXE-affected skin lesions displayed high AF intensity. During our measurements, significantly higher mean, minimum and maximu…
Early development of human Merkel cells.
1992
Human fetal Merkel cells are now generally considered to be epidermal derivatives. Previous studies using antibodies against the simple epithelial cytokeratins (CKs), 8 and 18, have demonstrated the presence of these cells in the epidermis at as early as fetal week 10 to 12. Using antibodies against CK 20 whose expression within the skin is restricted to Merkel cells, we applied immunofluorescence and immunoperoxidase microscopy to analyze earlier embryonic and fetal human skin (wk 7 to 9). We were able to demonstrate the first Merkel cells at as early as fetal wk 8, i.e., at the same time as the epidermis starts to develop an intermediate, third layer, characterized by the expression of CK…
Immunohistochemical markers for histopathological diagnosis and differentiation of acute cutaneous graft‐versus‐host disease
2021
Graft-versus-host disease (GvHD) is a major complication following stem-cell or solid-organ transplantation. Accurate diagnosis of cutaneous GvHD is challenging, given that drug eruptions and viral rashes may present with similar clinical/histological manifestations. Specific markers are not available. We performed the histological examination of biopsy samples from acute GvHD (aGvHD; n = 54), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN; n = 27), maculopapular drug eruption (MDE; n = 26) and healthy controls (n = 26). Samples of aGvHD showed a decrease in Langerhans cells (LC, p = 0.0001) and an increase in macrophages (MΦ, p = 0.0001) compared to healthy skin. Compared to …
Modified position-referenced microscopy for the analysis of low-magnification biological events: a case of study in the wound healing assay with a hu…
2016
Pseudo-Periodic Patterns embedded in cell-culture-plates are used for high-accurate-absolute retrieval of regions of interest in a wound healing assay of a hepatoma cell-line. The method shows more reliable results in the analysis of wound-area percentage.
Primary cutaneous biphasic sarcomatoid basal cell carcinoma with myoepithelial carcinoma differentiation: A new variant
2019
Isolated cases of basal cell carcinoma (BCC) with partial myoepithelial component have been described. However, myoepithelial differentiation has not been described in sarcomatoid basal cell carcinomas, which usually show features resembling osteosarcoma, chondrosarcoma, or leiomyosarcoma. We report a case of an 87-year-old man with a forehead lesion that histologically showed a minor component of conventional nodular BCC in transition with a major biphasic sarcomatoid growth composed of invasive spindle-cell and epithelial-like components, the latter with a reticular pattern and scattered ductal structures. Both components showed cytological atypia and high mitotic rate (26/10HPF), with at…
Psammomatous malignant melanoma arising in an intradermal naevus
2001
Psammomatous malignant melanoma arising in an intradermal naevus Aims: A wide variety of differentiation patterns may be found in malignant melanoma. Schwannian features are unusual, and mostly present in the desmoplastic variant. We report the first description of psammoma bodies in malignant melanoma. Methods and results: A malignant melanoma arose in an intradermal naevus of the scalp in a 51-year-old woman, displaying focal neural-like features in the form of rosette-like pseudo-meissnerian alveolar nests, as well as numerous psammoma bodies grouped in a few areas. Tumour cell immunostaining for S100, HMB45, NKI-C3, and vimentin was detected. In addition, both malignant and benign melan…
Intraepidermal formation of Merkel cells in xenografts of human fetal skin.
1990
An experimental transplantation model using human fetal skin was applied to approach the question of the embryologic origin of human Merkel cells. Palmar and plantar skin from five fetuses, between 8 and 11 weeks of estimated gestational age (EGA), was xenografted to subcutaneous beds of nude mice. After 4 or 8 weeks of growth, biopsies were taken from these xenografts and examined for the presence of Merkel cells, using immunocytochemistry with antibodies specific for simple epithelial-type cytokeratins and neuron-specific enolase (NSE) as well as using electron microscopy. Skin from the same fetuses at the time of transplantation was screened in the same way. In all fetuses, no (or very s…
Isolation, cultivation and characterization of human somatic stem cells from adult skin, adipose tissue and bone marrow
2008
Isolation, cultivation and characterization of human somatic stem cells from adult skin, adipose tissue and bone marrow
A novel monoclonal antibody to a distinct subset of cutaneous dendritic cells.
1992
A monoclonal antibody was generated by immunizing rats with Langerhans cell (LC)–enriched epidermal cells obtained from BALB/c mouse earskin after epicutaneous application of the contact sensitizer 2,4-dinitrofluorobenzene (DNFB). The antibody 4F7 detects in normal mouse skin, few dermal cells showing the morphologic, phenotypic, and functional properties of accessory dendritic cells, but lacking Birbeck granules. The capacity to stimulate allogenic T cells in the mixed leucocyte reaction resembles that of freshly isolated LCs. After DNFB application, an increased number of 4F7+ dendritic cells are found in the dermis and, in addition, some labeled dendritic cells occur in the epidermis. So…