Dousei Higuchi

Isolation of an extracellular proteinase (keratinase) from Microsporum canis.

Proteolytic activity was demonstrated when a strain of Microsporum canis was cultured in broth with human hair, but not in the medium without hair. The extracellular proteinase (keratinase) was isolated and purified by chromatography. Disc electrophoresis showed one protein band of extracellular proteinase, and the antibody against this enzyme gave a single precipitin line in agar diffusion. The IgG fraction completely neutralized the proteinase activity. The proteinase of M. canis may play a role in infection caused by this fungus, by affecting keratinized tissue such as stratum corneum and hair.

IMMUNOLOGICAL STUDIES OF AN EXTRACELLULAR KERATINASE

The extracellular keratinase from M. canis was purified using ion exchange chromatography and gel filtration. The purified enzyme showed a single protein band on sodium dodecyl sulfate‐polyacrilamide gel electrophoresis. A molecular weight of approximately 45,000 was determined by SDS‐electrophoresis.

Staphylococcal Scalded Skin Syndrome in an Adult

We report a case of a 77‐year‐old man with staphylococcal scalded skin syndrome (SSSS). The patient, who had no physical abnormalities other than herpes zoster, showed intact humoral and cellular immunity. A 3‐ and 1‐phage group strain of Staphylococcus aureus was isolated from an unruptured pustule of the herpes zoster lesion, but not from the throat. Inoculation of the isolated bacterium into newborn mice produced a characteristic Nikolsky sign. Histological diagnosis of SSSS was established by findings of intraepithelial cleavage through the stratum granulosum and a lack of inflammatory cells in both dermis and epidermis. After a ten‐day course of oral cefaclor (250 mg every 8 hours) and topical triamcinolone acetonide containing fradiomycin and gramycidin J, the patient recovered completely. The patient left the hospital without any scars other than those of herpes zoster.

Histological identification of prolonged survival of a skin allograft on an extensively burned patient

We applied skin allografts obtained from 38 unrelated volunteers to a very extensively burned female patient. Seven months after skin transplantation, one allograft from a male still survived clinically. In order to ascertain that the graft site resulted from growth of the male donor skin, the allografted area and patients own unburned normal area were examined by the fluorescent staining of Y-body (Y-chromosomal fluorescence). Y-body was detected in 57 per cent and 65 per cent of cells from the grafted area, whereas no fluorescence was detected in the patients own unburned normal area. These observations suggest that one allograft from an unrelated donor survived for 221 days on a very extensively burned subject.

Experimental Production of DLE Lesion with a Single Exposure to UVB (2.7 MEDs) Radiation

Keratotic erythematous lesions developed on the face, ears, neck, and upper back of a 38‐year‐old man. The patient had a history of photosensitivity to sunlight manifested by the development of new lesions. One week after an MED (2.7 mJ/cm2) was determined using UV‐B light, persistent erythema with fine scales were observed at test sites irradiated over 72 mJ/cm2. These lasted for at least 2 months. A biopsy specimen obtained from the test site irradiated at 72 mJ/cm2 showed liquefaction degeneration of the basal cell layer. Within the upper part of the dermis, perivascular and disseminated lymphocytic infiltrates were seen. However, when irradiated again under the same conditions 7 and 12 months after the initial phototest, no persistent erythema was observed.

Management of wounds treated by thrombin coagulation

Thrombin solution was applied to skin-graft donor sites following skin removal with a Reese dermatome. Immediately after the blood was clotted by the thrombin solution, sheets of silicone gauze were applied to the clotting site. Forty-eight hours after the operation, the coagulated blood had disappeared spontaneously. In a total of 21 operations, the wounds treated by the above method healed completely without infection.

Low-molecular-weight proteinase inhibitor of human epidermis inhibiting papain and trypsin activity.

SummaryA low-molecular-weight proteinase inhibitor was isolated from human epidermal extracts by means of ultrafiltration, gel filtration and ion-exchange chromatography. On polyacrylamide gel electrophoresis (PAGE), the isolated fraction exhibited a single band of activity at pH 9.4, and inhibitory activity against papain and trypsin was detected in this band. Using sodium-dodecyl-sulphate PAGE, the molecular mass of the inhibitor was estimated to be 2,200 daltons.

Inhibitory Activity of a Low‐molecular‐weight Proteinase Inhibitor (2,200 Mr.) against Various Proteinases

A low‐molecular‐weight proteinase inhibitor which has a molecular mass of 2,200 daltons was recently isolated from human epidermis. The isolated fraction demonstrated one protein band; when it was preincubated with papain, no band corresponding to products from the inhibitor was demonstrated in sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE). The isolated fraction was found to be immunologically distinct from a2 macroglobulin (α2‐M) by a double immunodiffusion test using anti‐α2‐M serum.

INFLUENCE OF HISTOCOMPATIBILITY ANTIGENS ON SKIN HOMOGRAFT SURVIVAL IN AN EXTENSIVELY BURNED PATIENT

Thirty‐eight donors were selected from 312 volunteers to be as nearly compatible as possible with the patients HLA‐A and ‐B antigens.