Search PubMed⌕ Search

Biomedical subjects

D M MacDonald

Publications and source records attributed to D M MacDonald.

At least 181 records · Page 10Linked to original sources
PubMed1982

The cell population in the cutaneous infiltrate of mycosis fungoides: in situ using monoclonal antisera.

T cell antigens were studied in cutaneous sections from five patients with mycosis fungoides (MF). The method allowed cell counting to be undertaken for each monoclonal antiserum. OKT3 (pan T cell) antiserum confirmed the predominantly T lymphocytic nature of the infiltrate, labelling the majority of infiltrating cells. OKT4 (helper/inducer) antiserum positively labelled 90% of the lymphocytes identified as OKT3 +. OKT8 (suppressor) antiserum marked only single or small groups of dermal lymphocytes, which comprised 24% of the cells identified as T lymphocytes. OKT6 (anti-Langerhans) showed positive labelling of dendritic cells in the epidermis and dermis. Fewer positively labelled epidermal dendritic cells were observed in sections from patients receiving PUVA, but no difference was found in the number of OKT6 positive dermal cells. The ratio of helper to suppressor cells in the dermal infiltrate significantly exceeded the normal circulating ratio.

Antibodies, Monoclonal↗
PubMed1982

Demonstration of histiocytes in the epidermal infiltrate of mycosis fungoides.

The presence of histiocytes in the epidermal and dermal infiltrate of mycosis fungoides was observed histochemically by revealing a diffuse pattern of acid alpha-naphthyl acetate esterase (ANAE) activity in the cytoplasm, and immunohistochemically by demonstrating the presence of histiocyte-specific 'enzymes', lysozyme, alpha-I-antitrypsin and alpha-I-antichymotrypsin. Histiocytes in the infiltrate of mycosis fungoides may be involved in antigen processing and interaction with T lymphocytes.

Histiocytes↗
PubMed1982

In-situ T lymphocyte identification in cutaneous tissue sections of benign and malignant dermatoses.

An indirect immunoperoxidase technique employing a specific anti-human T lymphocyte antiserum has been used to identify T lymphocytes in cutaneous tissue sections of various benign and malignant dermatoses. Skin biopsies from patients with histologically confirmed lichen planus, discoid lupus erythematosus, psoriasis, actinic keratosis, squamous cell carcinoma, Bowen's disease, keratoacanthoma, malignant melanoma, inflamed serborrhoeic warts, sarcoidosis, follicular lymphoma and multicentric reticulohistiocytosis were examined. T lymphocytes were found to be the predominant cell type in the cutaneous infiltrates of the majority of these dermatoses. However, only few T lymphocytes were identified in sarcoidosis where they tended to be restricted to the periphery of the epithelioid cell granulomas. Similarly, in the cutaneous infiltrates of follicular lymphoma and in a patient with multicentric reticulohistiocytosis, few T lymphocytes were identified.

Carcinoma, Squamous Cell↗
PubMed1982

The chloroacetate esterase reaction for mast cells in dermatopathology: a comparison with metachromatic staining methods.

This paper compares standard metachromatic methods with Leder's chloroacetate esterase reaction on mast cells in paraffin wax-embedded tissue of urticaria pigmentosa and a variety of inflammatory and benign neoplastic cutaneous conditions. Our conclusions are that Leder's method allows easier identification of mast cells and can be a useful adjunct to conventional metachromatic methods. The technique could be conveniently adopted in routine dermatopathology for mast cell identification.

Carboxylic Ester Hydrolases↗
PubMed1981

Intestinal permeability in patients with eczema and food allergy.

Polyethylene glycol (PEG) was used as a probe molecule to investigate intestinal absorption in eight patients with eczema and evidence of food allergy and ten with eczema alone. In both groups absorption of molecules of larger molecular weight was greater than in normal subjects but absorption of molecules of low molecular weight was normal. There was no difference in absorption between eczema patients with or without food allergy. These results suggest that there is an intestinal mucosal defect in eczema which exists whether or not there is coexistent food allergy. Half the patients with eczema alone and two of the eight with food allergy had more of the large molecular weight PEG recovered in their urine in the second 12 h after ingestion than in the first 12 h. This could be the result of abnormal permeability in the more distal small bowel or even in the colon.

Adolescent↗
PubMed1981

Juvenile xanthogranuloma with recurrent subdural effusions.

A 2-year-old girl with extensive cutaneous xanthogranuloma and recurrent subdural effusions has been investigated. Differentiation from histiocytosis X depended upon light and electron microscopical studies of the cutaneous infiltrate and cells obtained from the cerebrospinal fluid. The recurrent subdural effusions responded well to cranial irradiation. Although juvenile xanthogranuloma is generally a benign cutaneous disorder, a spectrum of naevoid proliferative changes involving systemic organs may occur.

Child, Preschool↗
PubMed1981

Zoon's balanitis (balanitis circumscripta plasmacellularis).

The clinical and histopathological features of nineteen cases of Zoon's balanitis and a comparable lesion of the vulva have been reviewed. The condition is particularly distinguished by characteristic histological changes affecting the epidermis and the dermal vasculature. The presence of a plasma cell infiltrate is relatively non-specific. Recognition of these features should allow simple differentiation from premalignant, infective and other inflammatory penile lesions which may be more responsive to treatment.

Adult↗
PubMed1981

The histopathology and ultrastructure of liver disease in erythropoietic protoporphyria.

The light, polarization and electron microscopic changes in the liver of four cases of erythropoietic protoporphyria (EPP) are described. In one of these cases liver involvement resulted in death, whereas in the other three there were no symptoms of referable to hepatic disease. In two cases hepatic pigment was readily visible on light and polarization microscopy and corresponded to characteristic crystalline aggregates seen ultrastructurally. Pronounced micronodular cirrhosis and cholestasis were present in the fatal case, while in the other only mild periportal fibrosis and mononuclear inflammatory cell infiltrate occurred. The third and fourth cases showed no evidence of hepatic involvement on light microscopy. Electron microscopy, however, revealed characteristic crystal-containing vacuoles indicative of protoporphyrin deposition. The need for early detection of the hepatic lesion is emphasized.

Adolescent↗
PubMed1981

Evaluation of acid alpha-naphthyl acetate esterase activity as a marker of T lymphocytes in benign and neoplastic cutaneous infiltrates.

Activity of the enzyme acid alpha-naphthyl acetate esterase (ANAE) in T lymphocytes and histiocytes in cutaneous tissue sections of patients with histologically confirmed lichen planus, chronic discoid eczema and mycosis fungoides was compared with results obtained using an in situ immunohistochemical technique employing an antiserum against the human T lymphocyte surface antigen (HTLA). In lichen planus and chronic discoid eczema, most of the cells in the cutaneous infiltrate exhibited both positive ANAE activity and the presence of HTLA. In mycosis fungoides, cells identified as T lymphocytes by the presence of HTLA often showed no ANAE activity. ANAE activity appears to be a useful marker of T lymphocytes in benign cutaneous infiltrates but is less reliable in labelling abnormal T cells.

Carboxylic Ester Hydrolases↗