Pyogenic granuloma: complete remission under occlusive imiquimod 5% cream.

An 82-year-old man was referred to our department for evaluation and treatment of a recurrent pyogenic granuloma on his right hand. After previous histopathological confirmation of the clinical diagnosis, he had been treated twice with electrocautery, but the lesion recurred 10 and 8 days later, respectively. After a 3-week topical application of imiquimod 5% cream twice daily under occlusion, complete remission of the lesion was achieved. Apart from an erythematous reaction in the apparently normal surrounding skin, the patient experienced no local or systemic side-effects. Since discontinuation of treatment he has been followed up for 8 months, and there has been no recurrence.

Peripheral large nerve fibre function in patients with chronic plaque psoriasis.

Accumulating evidence suggests the involvement of neurogenic inflammation in the pathogenesis of psoriasis. Moreover, the concomitant occurrence of peripheral neuropathy has been reported in several psoriatic patients. Thus, the aim of the present study was to answer the question whether an impairment of peripheral large nerve fibre function may exist in psoriasis. Thirty-two patients with severe and generalized chronic plaque psoriasis and 32 sex- and age-matched healthy controls were evaluated by detailed clinical neurological and standard neurophysiological examination. The latter included motor nerve conduction study of one nerve in the upper and one in the lower extremities and sensory nerve conduction study of one nerve in the upper and two in the lower extremities. Neurological examination failed to demonstrate any clinical evidence of large fibre neuropathy. Furthermore, all values of the examined neurophysiological parameters were within normal limits; comparisons of the corresponding mean values in the patient and the control group showed no statistically significant differences. These findings demonstrate no measurable abnormalities of the peripheral large nerve fibres in psoriatic patients and therefore an association of psoriasis with peripheral large fibre neuropathy cannot be suggested.

Age-related alterations in the carbohydrate residue composition of the cell surface in the unexposed normal human epidermis.

BACKGROUND: The results of the very few histochemical studies that have been performed so far on the lectin-binding profile of normal human epidermis are mostly controversial; thus, the carbohydrate residue composition of the cell surface in the latter still remains in dispute and the possible alterations in the epidermal lectin-binding profile are unknown. OBJECTIVE: To investigate the influence of age on the carbohydrate residue composition of the cell surface in unexposed normal human epidermis by means of lectin histochemistry. METHODS: Biopsy specimens obtained from the sun-protected (unexposed) buttock skin, divided into 5 age groups of 18 subjects each, were fixed in buffered formalin (10%) and embedded in paraffin. 4-mum sections were processed for histochemistry using a panel of six biotinylated lectins. RESULTS: In the unexposed normal human epidermis the concentration and distribution of cell surface beta-D-galactose, D-galactose-beta-(1,3 N-acetylo-D-galactosamine), beta(1,4 D-N-acetylo-D-glucosamine) and alpha-D-N-acetylo-D-galactosamine were almost identical in all age groups, whereas those of alpha-D-mannose, alpha-D-glucose and alpha-L-fucose revealed significant age-related differences. CONCLUSION: These findings may be due to an age-related decline in synthesis and/or transport of monosaccharides from the cytoplasm to the surface of epidermal cells. Thus, the corresponding lectins concanavalin A and Ulex europaeus agglutinin-I can only be used in comparative histochemical studies of the carbohydrate residue composition of the cell surface in the normal and pathological epidermis of individuals of the same age, whereas Ricinus communis agglutinin-I, peanut agglutinin, wheat germ agglutinin and Dolichos biflorus agglutinin, whose binding to carbohydrates is not affected by aging can be used in histochemical studies of carbohydrate residue composition of the cell surface in the normal and pathological epidermis in human subjects of any age.

Qualitative and quantitative alterations of cell surface carbohydrate residues during epidermal morphogenesis.

The purpose of this study was to investigate the carbohydrate residue composition of cell surface in the developing epidermis and to define the chronological sequence of its alterations in human fetuses from the 10th to the 20th weeks of gestation and at the 23rd week of gestation, using a panel of six biotinylated lectins: Concanavalin A, Ulex europaeus agglutinin-I, Ricinus communis agglutinin-I, Peanut agglutinin, Wheat germ agglutinin, and Dolichos biflorus agglutinin. Distinct qualitative and quantitative alterations in the expression of cell surface carbohydrate residues were found during epidermal morphogenesis prior to keratinization (10th to 20th weeks). At the 23rd week of gestation, the already keratinized fetal human epidermis revealed a pattern of cell surface glycosylation very similar to that of the adult human epidermis. Further studies are now warranted to answer the question regarding whether the glycosylation pattern in the developing human epidermis is disturbed in fetuses with genodermatoses and whether these disturbances might be important for prenatally diagnosing the latter.

Peripheral sensory neuropathy associated with short-term oral acitretin therapy.

A 57-year-old female patient with widespread chronic plaque psoriasis and a 32-year-old male patient with severe oral lichen planus are reported, who developed sensory symptoms in the extremities 3 and 4 months after the onset of oral acitretin therapy, respectively. Both patients showed clinical and electrophysiological evidence of a sensory peripheral neuropathy, which completely resolved 2 and 2.5 years after discontinuation of oral acitretin administration, respectively.

Sensorimotor polyneuropathy after a three-month oral acitretin therapy.

We report a patient with chronic plaque psoriasis who developed clinical and electrophysiologic features of polyneuropathy affecting motor and sensory fibers in upper and lower extremities after three months of treatment with oral acitretin. Drug withdrawal resulted in a complete clinical recovery and normalization of all electrophysiologic abnormalities within two months.

Stiff-person syndrome associated with oral isotretinoin treatment.

We describe a patient with severe nodulocystic acne who developed disabling muscle stiffness and painful superimposed spasms of the neck, back and upper limbs 10 days after the onset of oral isotretinoin treatment. The muscle hyperactivity condition, which revealed the clinical and electromyographic features of the stiff-person syndrome, gradually resolved 2 weeks after drug withdrawal.

Calcipotriol plus short-contact dithranol: a novel topical combination therapy for chronic plaque psoriasis.

The purpose of this double-blind randomised parallel-group study was to compare the efficacy and safety of short-contact treatment with dithranol ointment (2%) with its combination with calcipotriol ointment (50 microg/g) in 2 groups of in-patients with chronic plaque psoriasis. The patients of the first group (n = 23) topically applied dithranol once daily for 30 min and the vehicle of calcipotriol twice daily. The patients of the second group (n = 23) used a single topical application of dithranol for 30 min daily and additionally applied calcipotriol twice daily. The extent and the severity of psoriasis were assessed by means of psoriasis area and severity index score (PASI score) before the onset of the 6-week therapy and weekly thereafter. The difference between the two groups with regard to the mean PASI score became statistically significant already after the first week of treatment and remained so until the end of the trial. No significant differences were observed between the two groups with respect to the cutaneous adverse events. These findings indicate that the addition of calcipotriol ointment to short-contact dithranol markedly augments the therapeutic efficacy of the latter in chronic plaque psoriasis and impressively accelerates the response of psoriatic plaques to this well-tolerated regimen.

Effects of oral acitretin on contrast sensitivity and tear film function: a prospective study.

The purpose of this prospective study was to investigate the ocular side effects of short-term therapy with oral acitretin (1 mg/kg/day) in 24 patients with severe and recalcitrant dermatoses. Apart from the routine ophthalmological examination, the following tests were performed: break-up time of tear film for the determination of its stability, Schirmer test for the assessment of lacrimal gland function, rose bengal staining for the detection of possible ocular surface damage and contrast sensitivity test for the evaluation of visual function. No statistically significant differences could be found between the pretreatment values of the assessed parameters and those obtained after 1 and 2 months of therapy. It seems reasonable, therefore, to suggest that ocular surface integrity and tear film and visual function are not affected by short-term oral acitretin administration.

Effects of short-term oral acitretin therapy on peripheral nerve function: a prospective neurological and neurophysiological study.

The aim of the present prospective study was to substantiate possible side effects of short-term oral acitretin therapy (1 mg/kg/day) on peripheral nerve function of 13 patients with severe keratinization disorders. Clinical neurological examination before and 1 and 3 months after onset of treatment was unremarkable in all patients; however, a significant alteration of one or more neurophysiological, predominantly sensory, parameters was demonstrated in 3 out of 13 patients (23%) after 1 month and in 9 out of 13 (69%) after 3 months of oral acitretin therapy. These findings indicate that oral acitretin might be capable of causing a dysfunction of predominantly sensory nerve fibres in some individuals. Although in the investigated patients this dysfunction remained subclinical, it seems reasonable to suggest that neurological and neurophysiological evaluation of peripheral nerves should be added to the list of investigations that are routinely performed in patients receiving oral acitretin.

Inhibitory effects of arotinoids on tRNA biogenesis.

The effects of five arotinoids (Ro 13-7410, Ro 15-0778, Ro 15-1570, Ro 13-6298, Ro 40-8757) on ribonuclease P (RNase P) activity were studied in a cell-free system derived from Dictyostelium discoideum. RNase P is a ribonucleoprotein that endonucleolytically cleaves all tRNA precursors to produce the mature 5' end. Kinetic analysis showed that these compounds behave as classical competitive inhibitors with Ki values 4.35, 3.6, 2.8 and 0.045 mM for Ro 13-6298, Ro 15-1570, Ro 15-0778 and Ro 13-7410, respectively. Ro 13-7410 was 62, 80 and 97 times more potent in inhibiting the enzyme activity as compared to Ro 15-0778, Ro 15-1570 and Ro 13-6298, respectively, whereas Ro 40-8757 showed no effect on RNase P activity. These results project the significance of the acidic polar terminus in the arotinoid molecule binding to the enzyme. The kinetics of inhibition reflects allosteric interactions of arotinoids with D. discoideum RNase P. Moreover, our findings indicate that the inhibitory effects of arotinoids on tRNA biogenesis can be mediated through mechanisms not involving the retinoid nuclear receptors.

Additive inhibitory effect of calcipotriol and anthralin on ribonuclease P activity.

The effects of two antipsoriatic compounds, calcipotriol and anthralin, separately or in combination on ribonuclease P (RNase P), were investigated using a cell-free system from the slime mold Dictyostelium discoideum. RNase P is an ubiquitous and essential enzyme which endonucleolytically cleaves all tRNA precursors to produce the mature 5' end. The substrate for RNase P assays was an in vitro (32)P-labeled transcript of the Schizosaccharomyces pombe tRNA(Ser) gene supS1. Enzyme assays were carried out at 37 degrees in 20 microL 50 mM Tris-HCL 7.6 buffer, containing 10 mM NH(4)Cl, 5 mM MgCl(2), and 10% isopropanol. Calcipotriol or anthralin alone exerted a dose-dependent inhibitory effect on RNase P activity, with the former being more active than the latter in this respect. Simultaneous exposure of the enzyme to both drugs resulted in an enhancement of RNase P inhibition, which was additive. Considering the lack of structural similarities between the substrate (precursor tRNA) of RNase P and the tested drugs, it seems reasonable to suggest that their effects may be due to binding to allosteric inhibition sites of the enzyme. Although our in vitro findings cannot be directly extrapolated to the in vivo human condition, they do suggest that the inhibitory effects of calcipotriol and anthralin on tRNA biogenesis may be implicated in the mechanisms of their antipsoriatic action. Moreover, the additive inhibitory effect of these compounds on RNase P activity provides an experimental basis for their possible combined therapeutic application in the management of psoriasis.

Dose-dependent inhibition of ribonuclease P activity by anthralin.

The effect of five different anthralin concentrations on tRNA biogenesis was investigated employing the ribonuclease P (RNase P) of the slime mold Dictyostelium discoideum as an in vitro cell-free experimental system. RNase P is an ubiquitous and essential enzyme that endonucleolytically cleaves all tRNA precursors to produce the mature 5' end. Anthralin revealed a dose-dependent inhibition of RNase P activity indicating that this compound may have a direct effect on tRNA biogenesis. Taking into account that anthralin has no structural similarities to the substrate (pre-tRNA) of RNase P, it seems reasonable to suggest that this compound may bind to allosteric inhibition sites of the enzyme.

Lectin-binding pattern of primary malignant melanomas and melanocytic nevi.

A panel of six biotinylated lectins was applied in order to study the composition and distribution of plasma membrane carbohydrate residues in 83 primary cutaneous melanomas (MMs) and in 85 melanocytic nevi (MN) with the avidin-biotin peroxidase technique. No clear-cut differences between MN and MMs were observed with regard to the staining with lectins. In MN and MMs derived from different patients, the lectin-binding pattern was variable and heterogeneous even within the individual nevi or melanomas. It seems reasonable, therefore, to assume that the lectin-binding pattern cannot be regarded as a reliable histochemical marker for the differentiation of MN from MMs. Moreover, because the pattern reveals no statistically significant correlation with the thickness or the depth of invasion of MM, it seems to lack prognostic significance.