A new approach to the measurement of phospholipase A2 in tissue homogenates and its application to human skin.

We describe a new approach to the quantification of tissue phospholipase A2 based on the observation that the Vmax is increased by several orders of magnitude in the presence of high concentrations of dimethyl sulphoxide. The enzyme from human skin showed optimal activity at 30% dimethyl sulphoxide and pH 6-7.5, and had an absolute dependence on Ca2+ (apparent Km = 1.4 mmol/l). The relationship between reaction velocity and substrate concentration did not follow Michaelis-Menten kinetics. The enzyme was inhibited by p-bromophenacyl bromide, half-maximal inhibition occurring at 2.4 mumol/l. Surprisingly, assay of specimens of various human tissues indicated that, with the exception of pancreas, skin contained higher levels of phospholipase A2 activity than any other tissue investigated. Equally surprising was that primate skin (in particular human) seems considerably more active than that of other mammals. Speculatively, these findings may be related to the high levels of free fatty acids occurring on the skin surface.

Atypical psoriasis of the face and hands after PUVA treatment.

In sixty patients with psoriasis, two types of lesions developed after repeated and prolonged courses of PUVA radiation. In sixteen patients, new lesions on the face resembled seborrhoeic dermatitis; in thirteen patients thick plaques on the dorsum of the hands developed insidiously over the years. There was no significant association between the two types of lesions and only the latter were dose-related. The appearance of recalcitrant psoriasis on the face and hands appears to be a complication of PUVA treatment.

Effects of PUVA on human blood monocytes in vitro.

Adherent monolayer cultures of monocytes at two stages of maturation were exposed to long-wave ultra-violet radiation in the presence and absence of 8-methoxypsoralen. A remarkably predictable, dose-related lethal effect was seen, suggesting that mesenchymal cells in general may be sensitive to photochemotherapy (PUVA). Both monocytes and macrophages were lethally damaged with doses that may reach the dermis in the course of normal clinical therapy.

Lichenoid melanodermatitis. A clinicopathological study of fifty-one Kenyan patients with so-called tropical lichen planus.

Fifty-one Kenyan patients with variable round plaques on the exposed parts, predominantly on the face, and characterized by central hyperpigmentation with annular hypopigmented borders, are described. The clinical and histological picture showed transitions, which ranged from lichen planus and lichenoid poikilodermatous syndromes to dermatitis. This syndrome corresponds largely with (sub-)tropical or actinic lichen planus as reported from the Middle East, where emphasis has been given mainly to a part of the described spectrum of transitions. We suggest that this syndrome should be considered as one of Pinkus' regional lichenoid syndromes which represent hybrids between lichen planus and other conditions rather than as a mere variant of lichen planus.

Post-inflammatory elastolysis and cutis laxa.

Post-inflammatory elastolysis and cutis laxa (Marshall, Heyl & Weber, 1966) is a skin disease in African infants which appears to be comparatively common in at least two countries. Destruction of elastic tissue and atrophy are preceded by urticarial or by annular erythematous-popular lesions and result in severe disfigurement. The clinical features are intermediate between anetoderma (macular atrophy) and acquired cutis laxa, but sufficiently typical and characteristic to constitute a distinctive syndrome, which might represent an abnormal reaction to the bite of an arthropod.

Genital infections in developing countries: experience in a family planning clinic.

PIP: A study was undertaken to determine the incidence of 3 common genital infections in women seen at 1 urban and 1 rural family planning clinic in Kenya. 100 married and 100 unmarried women, 50 in each group making their 1st visit and not using contraception and the other 50 using contraception, were studied in Nairobi. 50 randomly-selected patients in a rural clinic were also studied. Laboratory procedures were carried out to identify gonorrhea, candidiasis, and trichomoniasis. Although these women represented largely the better educated and more professionally active strata of Kenyan society, more than 1/2 exhibited signs of at least 1 of these diseases; some had all 3 infections. These results are particularly noteworthy because most of the women had presented for contraceptive and not medical treatment. Gonorrhea occurred more often among unmarried than among married women, but there were no differences according to use or nonuse of contraceptives. The unmarried and the contraceptive users had more yeast infections. Family planning programs in Kenya and other areas of the developing world have a role to play in treating and controlling venereal diseases and genital infections. They must also combat the commonly-held notion that the use of contraception actually leads to such maladies, either through the contraceptive itself or through increased promiscuity.^ieng