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Biomedical subjects

J C Beani

Publications and source records attributed to J C Beani.

At least 19 recordsLinked to original sources
PubMed1995

Does manganese protect cultured human skin fibroblasts against oxidative injury by UVA, dithranol and hydrogen peroxide?

Reactive oxygen species (ROS) are involved in the mechanism of photoaging and carcinogenesis. Skin is endowed with antioxidant enzymes including superoxide dismutases (SOD): cytosolic copper zinc SOD and mitochondrial manganese SOD. The aim of our study was to estimate the protective effect of manganese against oxidative injury on cultured human skin fibroblasts. Dithranol, hydrogen peroxide and UV-A radiation (375 nm) were employed as oxidative stressors. The supply of manganese chloride produced an increase in cellular content of this element up to 24 fold without concomitant elevation of MnSOD activity. Nevertheless, manganese protects cells against two of the three ROS generating systems assessed, namely hydrogen peroxyde and UV-A. This protective effect depends on the concentration of manganese in the medium, 0.1 mM and 0.2 mM protect against UVA cytotoxicity, only 0.2 mM protects against H2O2 cytotoxicity.

Anthralin↗
PubMed1991

[Treatment of psoriasis by UVB and PUVA phototherapy].

PUVA has definitely proved effective in outbursts of extensive psoriasis vulgaris. Efficacy is enhanced by combination with retinoids. The pharmacokinetics of psoralen, which lead to adjustment of dosage to each case, is a concrete improvement which facilitates treatment. The side-effects of PUVA, and notably the risk of carcinogenesis, are well known and can be alleviated. UVB phototherapy, successfully used for a long time against psoriasis, has benefited from technical advances in the field of artificial sources of UV. In its conventional modality (wide UVB band), the adjunction of greasy excipients is necessary for efficacy. SUP and narrow-band phototherapy (311 nm lamp), more recently developed, are of considerable interest but ought to be further evaluated.

Carcinogens↗
PubMed1991

UV-induced squamous cell carcinomas in the hairless mouse. Morphological characteristics and transplantation in the syngenic and nude mouse.

Squamous cell carcinomas were induced by UVB in the hairless mouse HRO hr/hr. Twelve mice were irradiated three times a week at a dose of 0.19 J/cm2. The average latency period for the appearance of the first tumour is 16 weeks and by the 21st week, tumour incidence is 100%. Further observation of these tumours shows that their growth is independent of irradiation dose and that the tumours continue to appear even after cessation of irradiation. Histological and cytological examination of these tumours show them to have characteristics of malignancy. Transplantation in athymic mice suggests that UVB provokes immune deficiencies in hairless mice similar to those seen in conditioned nude mice.

Animals↗
PubMed1991

Psoralen plus ultraviolet A in the prophylactic treatment of benign summer light eruption.

We report the results of a French multicentre study to evaluate the efficiency of psoralen plus ultraviolet A (PUVA) therapy in the prophylactic treatment of benign summer light eruption (BSLE) and to establish the optimal protocol of radiation. Nine photobiology centres took part in this study; 83 patients (76 of them women) were evaluated. The radiation protocols were as follows: oral psoralen (8-methoxypsoralen; 0.6 mg/kg) was taken at each session; the starting dose of UVA radiation was determined according to skin type, with increments of 0.5 J/cm2 every 2 sessions. The subjects were randomized to receive 10-20 sessions 3 times per week. PUVA therapy was very effective: 68 patients (82%) reported total protection from BSLE. Four patients (5%) showed progress. Only 13% showed no improvement. The satisfactory results were not correlated with either the number of sessions or the J/cm2 of UVA. The intensity of tanning after the PUVA sessions did not appear to predict cure. Thirty-six percent of the patients had adverse reactions to treatment, including erythema, pruritus and triggering of BSLE. However, these effects only required the treatment to be stopped in 2% of the cases (for severe pruritus). The results in the various centres were similar.

Adolescent↗
PubMed1991

[Influence of retinoids on the bioavailability of methoxy-8-psoralen].

The retinoid-PUVA combination has been recognized as a satisfactory treatment of psoriasis. The absorption of 8-methoxypsoralen (8-MOP) is subject to wide interindividual variations under the influence of factors that are not yet known with certainty but are independent of age, sex and food taken at the same time as the psoralen. Whether concomitant retinoid administration influences the bioavailability of 8-MOP was considered an interesting question. The pharmacokinetics of 8-MOP were studied and compared in two populations of psoriatic patients: 119 patients treated with PUVA alone (psoralen-ultraviolet A) and 40 patients treated with the etretinate-PUVA combination (RePUVA). 8-MOP was assayed by the modified Ljunggren method 1 h, 1 h 30, 2 h, 2 h 30, 3 h and 4 h after ingestion of 8-MOP. The pharmacokinetic values recorded were: time and peak value of maximum plasma 8-MOP concentration (Tmax, Cmax) and area under the curve of time-related 8-MOP concentrations (AUC). The results obtained were as follows: Tmax PUVA 2 h 02 +/- 53 min RePUVA 1 h 56 +/- 50 min Cmax PUVA 159.12 +/- 88.85 ng/ml RePUVA 163.63 +/- 92.85 ng/ml AUC PUVA 343.33 +/- 211.06 ng*h/ml RePUVA 388.12 +/- 251.03 ng*h/ml Statistical analysis showed no significant difference in pharmacokinetic values between patients on PUVA alone and patients on RePUVA. Taking etretinate therefore does not alter the pharmacokinetics of 8-MOP and should not require any change in PUVA treatment.

Adolescent↗
PubMed1988

Randomized double-blind multicenter study comparing acitretin-PUVA, etretinate-PUVA and placebo-PUVA in the treatment of severe psoriasis.

A randomized double-blind study was designed with 65 patients in order to clarify two points: (1) does addition of a retinoid to psoralen-ultra violet A photochemotherapy (PUVA) of severe psoriasis decrease the UVA energy required to achieve remission, and (2) is there a difference between two retinoids, i.e. etretinate and acitretin. Acitretin-PUVA treatment was significantly superior to placebo-PUVA with respect to several items (decrease in lesional scores after 6 weeks of therapy, number of PUVA exposures, and total dose of UVA until remission). There were also differences between the etretinate-PUVA and placebo-PUVA groups, but only the decrease in lesional scores reached statistical significance.

Acitretin↗
PubMed1988

[Cutis marmorata telangiectatica congenita with body asymmetry].

One case of Cutis marmorata telangiectatica congenita (CMTC) is reported with cutaneous signs, corporal asymmetry, macrocephaly and cerebral vascular malformation. This syndrome allows to recognize a particular type of CMTC and its relationship with other angiomatosis.

Arm↗
PubMed1986

[Problems posed by the therapeutic use of photosensitizers in dermatology].

Three phototherapeutic regimens with photosensitization are now used in dermatology: PUVA (psoralen + UVA), TUV (crude coaltar + UV), PRT (phototherapy with hematoporphyrin derivative). The efficiency of PUVA and TUV is well known in several dermatoses. PRT is now being tested experimentally. For TUV, the lack of a standardized regimen does not allow a clear-cut evaluation of the therapy. For PUVA, late side-effects, particularly carcinogenicity have to be considered. To improve efficiency and minimize the side-effects of PUVA some procedures, such as association with retinoïds, pharmaco-kinetic studies for individual adaptation of the therapeutic regimen and the use of new less mutagenic psoralens are helpful. The persistent phototoxicity following treatments with hematoporphyrin derivative constitutes the major side-effect observed, for this phototherapy.

5-Methoxypsoralen↗
PubMed1985

Influence of the diet on the plasma kinetics of 8-methoxypsoralen.

The plasma kinetics of 8-methoxypsoralen (8-MOP) have been determined in 103 patients treated by PUVA in the routine conditions in which PUVA therapy is carried out in hospital. 8-MOP is taken with breakfast; four types of breakfast were available, which differed by their lipid content; this study showed that the diet has no influence on the bioavailability of 8-MOP.

Adolescent↗
PubMed1985

Screening for drug photosensitization activity by measuring the variations in oxygen consumption of Bacillus subtilis.

An original method is described for detecting the photosensitizing ability of a compound. The principle of this method is based on the analysis of variations in the consumption of oxygen by Bacillus subtilis (measured with Warburg's apparatus or an oxygenometric cell), induced by irradiation of the test compound added to the bacterial culture medium. This methodology was applied to 7 substances: 5 known photosensitizers (8-MOP, chlorpromazine, 5-fluorouracil, Vitamin A acid and benzoyl peroxide) and 2 products without any photoactive properties (aspirin and erythromycin). The comparison of results obtained with the method of photo-patch tests and the analysis of the photophysical properties of the compounds confirm the reliability, reproducibility and the quantitative nature of this method.

Aspirin↗