PUVA photochemotherapy in the treatment of psoriasis retrospective study in Qatar

PUVA alone was used on 20 patients with moderate to severe psoriasis [PS] with different clinical presentations. These psoriatics were of different age groups, skin types and nationalities. After PUVA treatment there was marked improvement or complete remission of [PS] in all patients. 95% of the patients had [PS] on their Extensors and Upper extremeties with more than one site involvement. Treatment was tolerated. Mean duration of treatment with PUVA was 10 weeks; mean dose/session was 10. 5 Joules. Mean number of sessions was 18, mean total cumulative dose [TCD] was 202.9 Joules. Mean dose for initial response was 6.29 J. Mean dose for maximal improvement was 16J. Mean number of sessions for maximal improvement was 13 sessions. PUVA treatment had no effect on all laboratory tests done in our patients. Treatment was convenient for [85%] of the patients. Psoriasis, photochemotherapy and details of our treatment protocol and its results are discussed with a review of the literature

Study of the skin concentrations after administration of the various phototoxic drugs

The skin concentrations of 8-methoxypsoralen (8-MOP), 5-methoxypsoralen (5-MOP), and 4, 5', 8-trimethylpsoralen (TMP) were studied in the guinea pig following oral administration and bathing. The skin concentration of phototoxic drugs after oral administration peaked at 1.5 hours, and the concentration of 8-MOP was 3.5 times greater than that of 5-MOP. The skin concentration of TMP was not detected in our study (limit of sensitivity 5ng/ml). The skin concentrations of phototoxic drug after bathing decreased in the order of 5-MOP, TMP, and 8-MOP

Quantitative and Morphologic Changes of Epidermal Langerhans Cell after Photochemotherapy in Guinea Pigs

We studied the number and morphologic alterations of ATPase-positive Langerhans cells (LCs) in guinea pig epidermal sheets and also performed electron microscopic observations on them following long-term systemic psoralen photochemotherapy (PUVA) using 8-methoxypsoralen (8-MOP) and trimethylpsoralen (TMP). We con-firmed that the LCs are sensitive to PUVA treatment. The LC depleting effects of PUVA are dose-related and the restorator1 of LCs takes place by the 4th week following cessation of PUVA. Neither psoralens alone nor UVA alone showed any effects on LCs. There were no significant differences between 8-MOP and TMP when comparing the effects of 8-MOP plus UVA and TMP plus UVA on LC numbers and morphology. It seems that a moderate dose of PUVA causes an actual decrease in the number due to cell damage. Also, it appears likely that giant LCs appear during and following PUVA treatment as a compensatory process of the remaining cells.

A Study on the Effect of Various Dosage of Khellin on Epidermal Melanocytes and a Comparison with Trimethylpsoralen in Systemic Photochemotherapy / 대한피부과학회지

Ninety black C 57 BL mice were divided into control and photochemotherapy groups. Control group was subdivided into a UVA 1rradiation only subgroup and a khellin only administration subgroup, while the phototherapy group was subdivided into one TMP and two khellin administration subgroups with dosages of 1.5mg/kg, 5mg/kg and 20mg/kg, respectivly. UVA was administered three thimes a week in a dose of 4J/cm for 4 weeks. Skin biopsies were taken at 0, l, 2, 3 and 4 weeks and the split DOPA stain was employed to observe pigment production. The number, size and circumference of the melanocytes were assessed. In summary, our results inclicate that khellin, which is slightly less effective than TMP at the same effective dose, is quite effective for pigment production and the degree of the production is dose related.

Study on the Pigment Producing Effect of Various Concentrations of Trimethylpsoralen in Topical Photochemotherapy / 대한피부과학회지

Topical photochemotherapy is effective for the treatment of vitiligo, However the effectiveness of photosensitizer, 4,5', 8-trimethyl-psoralen is not well known. For thesie reasons, we evaluated the pigment producing effect of various concentrations of TMP in fifty-six male black mice doing photochemotherapy. 1) The number of melanocytes according to the concentrations of TMP: The melanocytes were not increased in the control group. However, melanocytes were increased, in three TMP applied groups in the order of 0.1% 0.3% and 0.5% group at 1,2,3 weeks, respectively but the difference of melanocyte counts in the TMP applied groups was not remarkable at 4 weeks. 2) The area of melanocytes in relation to the concentrations of TMP: The area significantly increased from the second week of UVA exposure in the control group. There was marked increase in the area of the melanocytes in the TMP applied groups compared with those of control group in the order of 0. l%, 0, 3% and 0. 5% respectively. 3) The circumference of the melanocytes in relation to the Concentrations of TMP: Circumference of the control groups increased in proportion to the frequency of UVA exposure. TMP applied groups showed significant increase of the circumference compared that of the control group and generally increased in proportion to the increase in the concentration of TMP.