In vitro and in vivo study of 5-methoxypsoralen skin concentration after topical application.

The aim of this work was to study the skin distribution of 5-methoxypsoralen (5-MOP) after application of topical gels, in vitro and in vivo, in both healthy and psoriatic skin sites of 6 psoriatic patients. Drug skin distribution was determined using the thin slicing technique and subsequent HPLC analysis. In the presence of dermatological disease, i.e. psoriasis, the permeability of the tissue changed considerably, leading to an important increase in the cumulative amount of 5-MOP recovered in the skin after topical application. The amount of 5-MOP found in vitro in the human skin was intermediate between those cumulated in healthy and psoriatic skin sites during an in vivo experiment. The gel formulation is an efficacious carrier for the topical photochemotherapy of psoriasis with 5-MOP, since it allows drug penetration in psoriatic skin.

Plasma and skin concentration of 5-methoxypsoralen in psoriatic patients after oral administration.

The aim of this work was to investigate the distribution of 5-methoxypsoralen in the skin after oral administration of the drug and to examine the correlation between skin and plasma concentrations. 5-Methoxypsoralen skin concentration was measured in both healthy and psoriatic sites of 10 psoriatic patients after single and multiple oral doses. The results obtained show that 5-methoxypsoralen accumulates at higher levels in the more external layers of the skin after oral administration. The high affinity of drug for the stratum corneum was confirmed by in vitro skin affinity measurements. The concentration of 5-methoxypsoralen in the skin was similar in both psoriatic and healthy sites, indicating that the pathology does not influence drug distribution in the skin. After single dose administration, a linear correlation was found between skin and plasma drug concentration. After multiple dose administration, drug concentration in the skin was fairly constant despite the variable plasma concentrations in different subjects.

CREST staining of micronuclei from free-living rodents to detect environmental contamination in situ.

In this work immunofluorescent antikinetochore (CREST) staining was used to analyse bone marrow micronuclei (MN) from free-living animals belonging to four different rodent species. Yellow-necked mice (Apodemus flavicollis) and bank voles (Clethrionomys glareolus) were trapped in the Czech Republic, Algerian mice (Mus spretus) in Spain and house mice (Mus musculus domesticus) in Italy. Animals were collected in areas displaying low or high environmental pollution in order to investigate the sensitivity of CREST analysis on bone marrow MN as a biomarker of environmental stress in situ. Differences in total MN frequencies between animals collected in control or contaminated areas were statistically significant for two species, whereas the differences in CREST+ MN were statistically significant for three species. Interestingly, the percentages of CREST+ MN in animals collected in the control areas were very low (3. 2-8.7%), suggesting that activities inducing alterations in the distribution of chromosomes are very rare in natural conditions. The increased frequencies of CREST+ MN observed in areas with high environmental impact indicate that activities producing loss of chromosomes at mitosis may be characteristic of anthropogenic environments such as industrial settlements around petrochemical factories. Our data suggest that the analysis of CREST+ MN may represent a sensitive end-point for the detection of environmental contamination by genotoxic xenobiotics, offering the advantage of providing information on the mechanism of action of environmental contaminants.

Distribution of khellin in excised human skin following iontophoresis and passive dermal transport.

The aim of this work was to study in vitro khellin distribution into human skin after passive or iontophoretic transport. The experiments were performed on excised human skin, using vertical Franz-type diffusion cells. The effects of current application and reservoir pH were studied. At the end of the experiments the skin was sliced thinly and the drug was extracted and analyzed by HPLC. The results showed that khellin is able to penetrate through stratum corneum, to reach basal epidermis and upper dermis. The application time proved to be an important parameter. Current application (30 min; 0.5 mA/cm(2)), with a donor at pH 7.0, favored khellin accumulation even if the drug is not ionized. On the contrary, the use of a formulation at pH 3.2 inhibited drug accumulation. Leaving the drug reservoir in contact with the skin for 30 min after current application led to a dramatic increase of khellin concentration. A combination of dermal iontophoresis and passive diffusion is then a useful technique to govern khellin distribution in the skin.

Tyrosinemia type II: a challenge for ophthalmologists and dermatologists.

Tyrosinemia type II was suspected in a 13-month-old child with recurrent photophobia, tearing, and hyperkeratotic lesions on the palms and soles. Laboratory tests revealed high tyrosine levels in blood and urine. All the symptoms promptly improved after the institution of a low tyrosine diet. We emphasize the importance of an early diagnosis in order to avoid the risk of mental retardation in these patients.

A technique for the biopsy of oral lesions.

BACKGROUND: Biopsy of mucosal lesions can be carried out by means of several methods. OBJECTIVE: To describe a combination technique for the biopsy of mucosal lesions. METHODS: The combined effect of a chalazion forceps with a 4-mm punch allows the physicians to work on a stabilized, bloodless, and therefore simplified field. RESULTS: A preliminary suture with a 4-0 catgut chromic is the key step in assuring a safe post-operative hemostasis. CONCLUSION: This technique allows us to perform accurate and safe oral mucosal biopsies without any major side effects.

Multiple minute digitate hyperkeratoses.

A case of non-familial multiple digitate hyperkeratosis is reported. Digitate hyperkeratosis is a new, non-follicular disorder of keratinization and three different types have been distinguished in the literature: the familial type, with an autosomal dominant trait; the sporadic type; and the post-inflammatory type.

Prevention of post-herpetic neuralgia. Evaluation of treatment with oral prednisone, oral acyclovir, and radiotherapy.

The effects of prednisone, oral acyclovir, and radiotherapy were compared with placebo in the prevention of post-herpetic neuralgia. No treatment used was able to prevent, with statistical significance, post-herpetic neuralgia, although prednisone and acyclovir showed some pain reduction in the acute phase. Radiotherapy was of no value in either the acute or post-herpetic phase.

[Fluconazole in the treatment of dermatomycoses. Clinical experience]. / Il fluconazolo nel trattamento delle epidermomicosi. Esperienze cliniche.

Twenty patients suffering from dermatomycosis have been treated with fluconazole at the dose of 50 mg/daily for 20 days. These patients (10 M + 10 F) were aged 36 years on average (range 17-65 years). And were suffering from the following: Tinea pedis (3 cases), Tinea cruris (1 case), Tinea corporis (9 cases), Tinea versicolor (3 cases), Candidiasis (5 cases). One patient was suffering from Tinea on two different body sites. 19 patients finished the treatment and reported a complete clinical and mycological healing either at the end of the therapy on at follow-up visits. One patient, who was already suffering from gastritis, had to interrupt the therapy early due to abdominal pain. General safety was excellent.

T-cell infiltrate in lichen planus. Demonstration of activated lymphocytes using monoclonal antibodies.

Double layer immunocytochemical procedures were performed on fresh frozen serial sections of lichen planus (LP), using three monoclonal antibodies: OKT3 (T-cells) and two anti Ia-like antigens, monoclonal antibodies. Lymphocytes in dermal LP infiltrates were OKT3 positive and Ia-like positive; lymphocytes in the paracortical area of human normal lymph-node were OKT3 positive and Ia-like negative. Unstimulated peripheral blood-OKT3 positive, E-rosette forming cells of normal donors were Ia-like negative, while the same T-cells, when mitogen-stimulated, became Ia-like positive. Therefore, in dermal infiltrates of LP, T-lymphocytes are Ia-like positive cells, representing an antigen-stimulated T-cell population. The in situ presence of activated T-lymphocytes seems to support the hypothesis of an immunological nature of LP.