QTL analysis of seed dormancy in Arabidopsis using recombinant inbred lines and MQM mapping.

The genetic differences for seed germination between two commonly used Arabidopsis thaliana ecotypes Ler and Col, both showing a low level of seed dormancy, were investigated. The analysis was performed with 98 recombinant inbred lines (RILs) derived from the cross between the two ecotypes, and these lines had previously been analysed for molecular marker composition by Lister and Dean (Norwich, UK). The analysis of germination was performed on seeds grown in three different maternal environments and each seed batch was tested in three different germination environments: in light, in darkness and in the presence of the gibberellin inhibitor paclobutrazol. Fourteen loci were identified using the multiple-QTL-model (MQM) procedure for mapping quantitative trait loci. At nine loci no significant interaction between the detection of the locus and environmental factors could be detected. However, three other distinct loci controlling the germination behaviour in the presence of the gibberellin inhibitor paclobutrazol had a much lower or no effect when germination was tested in water either in light or darkness. Two other loci affecting germination in darkness and/or light had practically no effect on germination in the presence of paclobutrazol.

[Scratching for the itch in eczema; a psychodermatologic approach]. / Krabben tegen de jeuk bij eczeem; een psychodermatologische benadering.

Atopic dermatitis patients often complain of intense itching and excessive scratching. Apart from standard therapies of antihistamines with sedative side effects, there are patients who appear not to respond satisfactorily to standard medical treatments. As itching can be a skin manifestation of psychological disturbance, these patients may benefit from behaviour treatment of scratch behaviour which can have a beneficial effect on the course of atopic eczema. The scratch response is considered a classical conditioned habit and special attention was given to the function of behaviour. Two patients, a man of 27 and a girl of 11, were suffering from intractable atopic eczema. The first patient was required to record his own scratching in a diary which is part of awareness training regarding scratch situations. In the second patient impaired parent-child relationships were the main discriminative stimuli to provoke scratch behaviour. It was shown that behaviour therapy helps patients who scratch repeatedly to exercise voluntary control over it.

The psychological impact of severe acne.

The extent to which severe acne affects patients' personality and emotional life is still undetermined. The personality factors of neuroticism, psychosomatic condition, social extraversion, and self-defensive attitude were tested, as well as the social anxiety, in a group of forty patients with severe acne. They were more neurotic, more concerned about their bodily functions, and had a lower self-defensive attitude than a normal population. Their anxiety level was also significantly elevated. A subgroup of twelve patients with conglobate acne were treated with isotretinoin. After one year, when the disease had been brought under control effectively, they were retested. The personality factors had not changed consistently. A decrease of anxiety, which did not reach a level of significance, was found. We conclude that the personality and emotional life of patients with severe acne are affected. This aspect of their condition should receive proper attention as part of their treatment.

An evaluation of PUVA-therapy for alopecia areata.

30 patients with alopecia areata were treated with 8-methoxypsoralen orally combined with whole body UVA exposure. 9 patients showed more than 60% regrowth of hair, 8 of them had recurrences of hair loss within a mean time of 7.7 months. No selecting criteria could be found prophesying good results of PUVA therapy.

Normal sweating and tear production in congenital ichthyosiform erythroderma with deafness and keratitis.

A 24-year-old female patient with congenital ichthyosiform erythroderma, deafness and vascularizing keratitis yet also examining normal sweating and tear production when tested is reported. This unique finding indicates that a certain subgroup of patients with this generalized ectodermal disturbance may benefit from treatment with the aromatic retinoids.

Hereditary congenital hypopigmented and hyperpigmented macules.

Congenital hypomelanotic and hypermelanotic macules traced in three generations of a family suggested autosomal dominant inheritance. Some affected membbers also showed retarded growth and mental deficiency. Light microscopic findings of "splitdopa" preparations of lesional and normal skin were comparable, except that background staining of keratinocytes in dark macules was higher than in control skin. In light macules it was lower. Ultrastructurally, hypomelanotic skin showed small melanosomes (0.3 mu) that occurred in keratinocytes in melanosome complexes. Hypermelanotic skin revealed large melanosomes (0.6 mu) that were singly distributed in keratinocytes. Melanosome size in normal skin averaged 0.4 mu; distribution pattern was mixed. Melanin granules inside keratinocytes were fully melanized. Hyperpigmented, normal and hypopigmented skin of one person had histological features of black oriental and white skin. This clinical picture could well represent a new neurocutaneous syndrome different from tuberous sclerosis.

Psychometric investigation in 48 Dutch patients suffering from psoriasis.

48 psoriasis were compared with patients suffering from a variety of psychosomatic diseases, with regard to neuroticism, extraversion and self-defensive attitude. In addition, a Social Anxiety Scale was administered to the psoriasis patients to evaluate the patient's concern of his appearance in social situations. Finally, some psychometric data, which differentiated between the males and the females of the psoriasis group, are discussed.