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Biomedical subjects

J Kanitakis

Publications and source records attributed to J Kanitakis.

At least 181 records · Page 10Linked to original sources

[Hashimoto-Pritzker congenital self-healing histiocytosis].

A full-term female infant was born with numerous purple firm indolent papulonodular lesions, occasionally ulcerated, ranging in size from 1 to 8 mm, scattered all over the body. The liver, spleen, lymph nodes were normal, as were the blood count, skull and chest X-ray. Biopsy of a skin lesion showed a deep dermal infiltrate consisting of histiocytic cells which were OKT6 +, HLA-DR + and S 100 +. Electron microscopy revealed numerous dense bodies, often with a myelin-like core and some Birbeck granules. The clinical course was favourable with a spontaneous regression of all lesions, sometimes through a central necrosis or atrophy, within 8 weeks. Congenital self-healing reticulohistiocytosis (CSHR) is characterized by a neonatal onset, with purple or necrotic nodular lesions showing the histopathologic aspect of histiocytosis X (although Birbeck granules are less numerous), an absence of visceral involvement and a spontaneous regression within the first 3 months of life. The place of CSHR among histiocytosis is discussed.

Female↗

[Use of cultured epidermis of human origin for demonstrating the acantholytic action of staphylococcal exfoliatin A].

Cultured human epithelia obtained from epidermal cells in vitro were used to assay the activity of staphylococcal epidermolytic toxin and develop an in vitro experimental model for the staphylococcal scalded skin syndrome. Human epidermal cells were grown from single epidermal cell suspensions obtained through trypsinization of adult normal skin into multilayered epithelia (with a basal cell layer, several intermediate and one or two upper layers) on mouse 3T3 feeder cells. First passage cultures were incubated with exfoliative toxin A from phage Group II staphylococci at various concentrations in DMEM. They were examined at various time intervals by direct microscopic and histological examination of respectively the culture plates or the epidermal sheets after their detachment from the plates with dispase grad II. A total exfoliation could be obtained at 24 hour at concentrations of Img and 500 micrograms/ml, only local areas of epidermolysis noted at 100 micrograms/ml. The intraepithelial separation was noted to occur between the basal layer and the lowest intermediate layer. No exfoliation could be observed at lower concentrations. Up to 4-5 hours few changes were evident, but at this time small areas of epidermolysis developed. With exfoliatin 100 micrograms/ml, intraepidermal blisters were clearly visible, occurring either between the basal cells and the lowest intermediate layer or between the first two intermediate cell layers. At the ultrastructural level, desmosomes were sparse and altered, with enlargement of the intercellular spaces and condensation of tonofilaments. These data indicate that human epidermal cell cultures, although their differentiation in culture only mimics what occurs in vivo, can be used as an in vitro model of the staphylococcal TEN to further investigate the site of action of such a toxin and the cellular mechanism responsible for the syndrome.

Adult↗

Cutaneous angiomas in POEMS syndrome. An ultrastructural and immunohistochemical study.

Cutaneous manifestations of POEMS (polyneuropathy, organomegaly, endocrinopathies, M-protein, and skin changes) syndrome in a 51-year-old white man included two types of hemangiomas, ie, cherry-type and subcutaneous hemangiomas. By light microscopy and immunohistochemistry, both types of tumors showed features of capillary hemangiomas. By electron microscopy, a peculiar finding of subcutaneous hemangiomas was the presence of slender abluminal processes of endothelial cells that were frequently anastomosing to form electron-lucent blebs. Although the precise etiopathogenesis of the vascular proliferations remains speculative, these lesions merit study since they constitute an easily recognizable marker of POEMS syndrome.

Estrogens↗

Ultrastructural studies of cultured human epithelial sheets used as skin allografts.

In this work the ultrastructural features of cultured epithelial sheets (CES) used as skin allografts in humans are described, before and at various times after grafting. Prior to grafting, CES consisted of 4-5 layers of keratinocytes of a low to moderate degree of differentiation. However, after grafting, the CES developed progressively but rapidly features of a well-differentiated epidermis (including melanocytes and Langerhans' cells) and a dermal-epidermal junction. No evidence of rejection was observed. These results demonstrate the key role of normal dermis in the maturation of the surface epithelium and prove the suitability of CES as skin allografts.

Cells, Cultured↗

Expression of neural-tissue markers (S-100 protein and Leu-7 antigen) by sweat gland tumors of the skin. An immunohistochemical study.

The expression of two immunohistochemical markers of neural tissue and of cutaneous sweat glands (S-100 protein and Leu-7 antigen) was studied in a group of cutaneous epithelial, mostly glandular, tumors. These antigens were detected only on sweat gland neoplasms showing both types (eccrine and apocrine) of differentiation. These results suggest that antibodies to S-100 protein and to Leu-7 antigen have a limited value in the distinction between eccrine and apocrine tumours, but they may serve as a useful adjunct for the confirmation of the glandular differentiation of cutaneous epithelial tumors.

Antigens, Differentiation, T-Lymphocyte↗

Localized cutaneous cryptococcosis successfully treated with ketoconazole.

A 27-year-old female recipient of a renal allograft, treated with systemic steroids and azathioprine, developed progressive cutaneous lesions (an ulcer, a nodule, and an abscess). Histopathologic and tissue-culture examination of the skin lesions led to the diagnosis of cutaneous cryptococcosis. A description of the light and electron microscopic features of the cutaneous lesions is reported. A thorough visceral investigation failed to detect systemic involvement. The patient was treated with oral ketoconazole (400 mg daily) for 6 months. A gradual healing of the lesions was obtained, and cultures performed 3 months after the onset of treatment failed to show Cryptococcus neoformans. No relapse or dissemination has so far been observed.

Adult↗

Involucrin expression in keratinization disorders of the skin--a preliminary study.

We have studied the expression of involucrin in a variety of keratinization disorders, mostly of genetic origin using an avidin-biotin-peroxidase technique. In normal human epidermis 25% of the living epidermis was labelled. The diseases studied fell into two groups. Diseases with greatly increased involucrin staining including collodion baby (38%), Darier's disease (49%), Flegel's disease (56%), erythrokeratoderma variabilis (60%), epidermal naevus with epidermolytic hyperkeratosis (45%) and congenital bullous (58%) and non-bullous (44%) ichythyosiform erythroderma; and diseases with normal or slightly increased staining, including ichthyosis vulgaris (27%), X-linked ichthyosis (25%), confluent and reticulate papillomatosis (27%) and simple epidermal naevus (28%). These results demonstrate that involucrin expression is altered in some keratinization disorders and suggest that in such conditions cellular functions other than keratin metabolism are also affected.

Humans↗

Growth and differentiation of human epidermal cultures used as auto- and allografts in humans.

Human keratinocytes from small skin specimens were grown on mouse 3T3 cell feeder layers into epidermal sheets free from Langerhans cells and MHC class II antigen. These were found to be suitable for the permanent coverage of wounds when used as autografts or allografts. We report here the ultrastructural differentiation of this cultured epidermis after grafting onto autologous or allogeneic recipients. The cultured epidermis was a thin but multilayered Malpighian epithelium composed of keratinocytes at different stages of differentiation. The dermo-epidermal basement membrane was newly synthesized during the first few days following transplantation onto de-epidermized wounds. The analysis of keratins and examination of various keratinocyte membrane antigens by immunofluorescence indicated that full terminal epithelial differentiation was only achieved after in vivo transplantation of the cultured epidermis. Langerhans cells, absent in cultures, progressively colonized the grafts, while melanocytes, not detectable in sections of the cultures, were identified among the keratinocytes 2 weeks after grafting.

Adolescent↗

Eccrine syringofibroadenoma. Immunohistological study of a new case.

Eccrine syringofibroadenoma is a rare tumor considered to originate from the excretory portion of the eccrine sweat gland. A new case of this lesion, whose acrosyringeal differentiation was underlined by an immunohistological study using antibodies to keratin and involucrin, is reported herein.

Adenofibroma↗

Expression of blood group antigens by cultured human epidermal cells used as allografts.

The expression of blood-group antigens was studied on human epidermal cultures used as allografts in 13 non-immunosuppressed patients treated for leg ulcers. The study was carried out using monoclonal antibodies to A and B antigens by an indirect immunofluorescence technique. Blood-group antigens are weakly expressed on the suprabasal layers of the cultured epidermal sheets. After grafting, the donor's blood-group antigens were detected on a few cells of the suprabasal layers. Furthermore, scattered keratinocytes as well as acrosyringia were found to express the recipient's blood-group antigens.

Antigens↗

[Immunolabeling methods in cutaneous histopathology. Principles and practical applications].

Immunohistochemical methods, introduced more than 40 years ago, represent a favourite technique in the histological diagnosis of cutaneous diseases. Their practical applications, that initially concerned merely auto-immune dermatoses, have spread over many other nosologic groups of skin pathology. The improvement of immunolabelling techniques and of reagents has rendered the immunohistochemical methods much more reliable and has contributed to their spreading. Enzymatic techniques, by virtue of their advantages over fluorescent techniques, are being used more and more frequently. The continuous production of new antibodies (polyclonal but mainly monoclonal) renders possible the immunohistochemical detection of the different cellular or extracellular, epidermal and dermal components of the skin. The main chapters of cutaneous pathology, aside from auto-immune diseases, that concretely benefit from immunolabelling techniques, concern: a) the diagnosis and histogenetic study of tumoural lesions, b) the diagnosis and classification of bullous diseases, c) infectious diseases.

Autoimmune Diseases↗