Search PubMedSearch

Biomedical subjects

N Hunziker

Publications and source records attributed to N Hunziker.

At least 19 recordsLinked to original sources

Sensitization to the isothiazolinone biocide. Report of the Swiss Contact Dermatitis Research Group 1988-1990.

The rate of sensitization to isothiazolinones (Kathon CG) detected in Switzerland rose from 3.5% (out of 2,491 patients) in 1987 to 6.3% (out of 982 patients) in 1988 and 5.6% (out of 2,295 patients) in 1989-90. This rate of sensitization appears to be related to the more and more widespread use of isothiazolinone biocide in cosmetics, domestic products and in industry.

Cosmetics

Prurigo nodularis: a reappraisal of the clinical and histologic features.

Study of 14 patients with prurigo nodularis revealed that clinically the lesions were multiple, verrucous, and discrete and were set in normal-appearing skin. Microscopically, the lesions showed a vascular acanthomatous mass. The dermal nerves showed a tendency toward hyperplasia in parallel with the epidermal and vascular changes, but no evidence of neuroma formation was seen. Electron microscopic examination showed disorganization of the normal pattern of the myelin sheaths and axons of the dermal papillary nerves. The presence of epidermal mast cells was noted in the biopsy specimens of prurigo nodules from eight of the 14 patients.

Adult

[Cowden disease: report of 8 cases in 2 families (author's transl)].

These 8 cases of multiple hamartoma syndrome are the first reported in Switzerland. Two men aged respectively of 65 and 28 years presented a cobblestone appearance of the gingiva and of the tongue ("pebbly tongue"), which suggested Cowden disease. This diagnosis was confirmed by the discovery of numberous skin lesions, a thyroid goiter, gastrointestinal polyposis, and a mild skelettal dysmorphosis. The older patient had a grade one carcinoma of the bladder; his son and his daughter presented the syndrome, which was also discovered in the family of the second patient (his father, his brother, his sister and one of her daughters). The ultrastructural study of two skin biopsies demonstrated anomalies of the fibroblasts and collagen fibers.

Adolescent

Animal models of percutaneous penetration: comparison between Mexican hairless dogs and man.

In an attempt to find better animal models for percutaneous penetration studies relevant to man, urinary excretion of 14C-labeled compounds was studied in the Mexican hairless dog and in man. With benzoic acid, progesterone and testosterone, the total absorption and maximum absorption rate were greater in man than in the hairless dog. As urinary excretion lasted days longer in the dog than in man, it is possible that the thin dog skin held the chemicals longer than man. Surface-counting experiments with a Geiger counter with a thin mica window protected by a special screen of fine stainless steel wires showed that benzoic acid and progesterone did persist on the dog skin far longer than on human skin. We conclude that the Mexican hairless dog has permeability characteristics significantly different from those of human skin.

Administration, Topical

Langerhans cells in contact dermatitis of the guinea pig.

In the guinea pig, the epidermal Langerhans cells studied by adenosine triphosphatase and electron microscopic techniques in dinitrochlorobenzene-induced contact dermatitis showed early cellular vacuolar and granular changes and intraepidermal contact with mononuclear cells. At later periods of up to 48 hours, the Langerhans cells migrated to the surface of a thickened epidermis and were lost in the parakeratotic horny layer that was shed. Thus, the Langerhans cell probably has a macrophage-type role in the epidermal reaction of contact dermatitis, and as the sponglosis and the inflammatory reaction develop, these cells are shed with the degenerating keratinocytes.

Animals

[Essential melanic pigmentation of the mouth and the lips].

Lenticular or linear, buccal or labial, slate-coloured or melanic black spots are noticed in healthy subjects with no racial, hormonal or drug factor. Histological examination shows a pigmentary excess of the basement membrane without anomaly or dystrophy or nevus cells. Ultrastructural study shows a great number of intracyto-plasmic melanosomes, isolated or in group in all the keratinocytes in the third inferior part of the epidermis. No explanation can be given to this melanocyte hyperactivity. An excision can be done without danger for esthetical purpose.

Basement Membrane

Cell populations in experimental contact dermatitis.

Sequential biopsy specimens from contact dermatitis induced in the guinea pig by the application of dinitrochlorobenzene were studied by histologic, histochemical, and electron microscopical methods. At 12 hours, mononuclear cells and polymorphonuclear cells reached their peak numbers. Increasing numbers of basophils were observed, and at 24 and 48 hours, the basophils reached their maximal numbers. The basophils were observed not only in the dermis but also in the epidermis, and they may have had an active role in inflammation or repair. A close relationship was noted between the macrophage and all of the successive cell populations in the dermis.

Animals