We have observed the dark effect of 8-methoxypsoralen (8-MOP) on the viability and DNA synthesis in human lymphocyte cultures after stimulation with phytohemagglutinin (PHA) in the absence of ultraviolet A radiation. The concentrations of 8-MOP was 0.5-3.2 microgram/ml. We have also measured the LDH activity in supernatants of lymphocyte cultures treated with 8-MOP. The results were as follows: 1. There was no 8-MOP dose-dependent decrease in the viability of lymphocytes up to 8MOP 32microgram/ml. 2. There was 8-MOP dose-dependent decrease in PHA-induced DNA synthesis of lymphocytes from the concentration of 8-MOP 2microgram/ml. 3. There was a time-dependent decrease in PHA-induced DNA synthesis of lymphocytes at the conscentration of 8-MOP 32microgram/ml. 4. There was no LDH release in supernatant of lymphocyte cultures after incubation with 8-MOP up to 8-MOP 32microgram/ml.
DNA* ; Humans* ; Lymphocytes* ; Methoxsalen*

BACKGROUND: Photochemotherapy (PUVA) is the effective treatment for vitiligo. It is necessary to measure the minimal phototoxic dose (MPD) in order to ascertain a safe, effective UVA dose needed for irradiation during photochemotherapy. OBJECTIVE: The purpose of this study was to standardize the MPD for vitiliginous lesions. METHOD: The MPD was measured in 124 vitiligo patients. The number of patients monitored for topical and systemic MPD using the photosensitiser, 8-methoxypsoralen (8-MOP) were 41 and 83, respectively. MPD was also analysed according to sex, age, site of the vitiliginous lesions, duration of disease, season and administration route of the photosensitiser. RESULTS: 1. In the group assessed for topical application of 8-MOP cream, mean MPD was 0.62+/-0.59J/cm2. 2. In the group assessed for systemic administration of 8-MOP, mean MPD was 2.68+/-1.83J/cm2. 3. MPD in the group systemically administrated with 8-MOP was 4.32-fold to that of the topical application group (p<0.01). 4. In the case of both topical and systemic administration of the photosensitiser, 8-MOP, no significant differences in MPD were found due to the sex, age, site of vitiliginous lesions, duration of disease, or season in which MPD was administered to patients. CONCLUSION: There was a significant difference in MPD between the topical application group and the systemic administration group.
Humans ; Methoxsalen ; Photochemotherapy ; Seasons ; Skin* ; Vitiligo

BACKGROUND: It is mandatory to measure the minimal phototoxic dose(MPD) in order to determine adequate irradiation of UV-A in photochemotherapy. However, the measurement of MPD is not easy in some cases due to inadequte size and site of lesions, time and manpower. OBJECTIVE: The purspose of this study was to standardize the minimal phototoxic dose for a vitiliginous lesion. METHODS: The minimal phototoxic dose of UV-A was measured in 82 vitiligo patients. Then we analyzed the MPD according to the sex, age, site of the vitiliginous lesions, duration of disease, and administration route of the photosensitizer. RESULTS: 1. There were no significant differences between exposed and unexposed areas in MPD in both cases of topical and systemic administration of the photosensitiser. 2. There was no significant correlation between disease duration and MPD in both cases of topical and systemic administration of the photosensitiser. 3. In the group of topical application of 8-methoxypsoralen cream, MPD for males and females were 0.53+0.38J/cm2 and 0.48+0.32J/cm2 respectively without significant difference in sex. 4. In the group of systemic administration of 8-methoxypsoralen, there was a significant difference between males and females in MPD. The MPD in males and females were 1.38+0.72J/cm2 and 2.51 + 1.40J/cm2, respectively. 5. In the group of topical application of 8-methoxypsoralen cream, the MPD in 2nd decade patients was the highest(0.80+0.55J/cm2). The MPD had a tendency to decrease gradually as age receded from the 2nd decade. 6. In the group of systemic administration of 8-methoxypsoralen, there was a tendency for the MPD to be increased according to age without statistical significance. 7. MPD in the group systemically administrated with 8-methoxypsoaralen was four-fold to that of the topical application group. CONCLUSION: It may be valuable to keep in mind that there was a statistical differrence in MPD between sexes in systemic administration of the photosensitizer, and that MPD was different according to patients age in the topical application group.
Female ; Humans ; Male ; Methoxsalen ; Photochemotherapy ; Skin* ; Vitiligo

The present study was carried out to find a simple and safe in. vitro test for phtotoxic drugs. Authors selected two strains of Salmonella typhimurium(TA98 and TA102) which have been used in Ames test for the detsction of mutagenecity af various chemical substances. Both strains are genuine products of genetic enzineering. The etrain TA98 should be highly vulnerable to ultraviolet radition because it lacks normal I)NA excision repair gene. The strain TA102 was chosen as control since it maintained the DNA repair gene. These strains were subjected to increasing dosea of UVA with or without pretreatment of 8 methoxypsoralsn(8-MOP) which is a prototype of photatoxic druge. The authors made use of a perforated stain-less steel template which provided a simple and eosy monitoring of ultraviolet irradiation effects i.e. clear zones due to inhibition of the atrains could be determined. By using this methad, the authors acquired the following results .' I. 8-MOP alone exerted no inhibition on both strains at concentration upto 100mg /ml. 2. UVA irradiation alone showed no growth inhibition at dose upto 5J/cm. 3. UVA irradiation after pretreatment with 8 MOP resulted varying growth inhibition in proportion to irradiation doses. 4. Authors found a suitable concentration of 8-MOP for this test is 10pg/ml. With this ccncentrstion, minimal phatatoxic dose of UVA were O.l J/cm for the strain TA98 and 1.0J/cm for the strain TA102 respectively.
Dermatitis, Phototoxic ; DNA Repair ; Methoxsalen ; Salmonella ; Steel

Among ]20 vitiligo patients who visited our clinic during the period of January 1984 to February 1985, 39 patients were treated with oral methoxsalen (8-MOP) and UVA for more than 6 months, The following conclusions were obtained by analysis of the clinical histories and efficacy of PUVA treatment: 1. The mean age of 39 patients was 31 and that of onset was 21. An average of 1() years elapsed from the onset of the disease prior to visiting our clinic. The initial involvement was observed, in decreasing order of frequency, on the trunk, face and/or neck and extremities. 3, The repigmentation started most frequently from the trunk followed by the extremities, face and/or neck after treatment of 2 months and 14 irradiations on the average. 4, There was a direct relationship between the frequency and duration of treatment and its effectiveness. 5. The trunk showed the best response to the treatment, followed by the extremities; face and/or neck. The most resistant sites were the the hand and/or foot. 6. No specific relationship was found between the patient's age, duration of illness and responsiveness to the treatment. 7. The side effects were minimal and transient.
Extremities ; Foot ; Hand ; Humans ; Methoxsalen* ; Neck ; Vitiligo

Pityriasis lichenoides chronica is characterized by unknown etiology, chronicity and by being essentially asymptomatic and refractory to therapy. Nine patients with pityriasis lichenoides chronica were treated with orally administrated 8-Methoxypsoralen and UVA irradiation(PUVA Therapy). After S-45 PUVA treatments, lesions were completely cleared.
Humans ; Methoxsalen ; Pityriasis Lichenoides* ; Pityriasis* ; PUVA Therapy*

In order to measure the MPD with 8-methoxypsoralen, we selected 49 Korean healthy male vlunteers without phototoxic or photosensitive dermatoses. They were divided to 3 groups (Immediate; group 1, 1 hour; group 2, 2 hours', group 3) according to the waiting time, intervals of application of photosensitizer a,nd UVA:irradiation. The reaults were summarized as follows: 1. MPDs of group 1 had no clinical significance. 2, MPDs of group 2 were more than those of group '3 independently of application methods of photosensitizer. 3. In the cases of topical application of 8-MOP, MPDs of group 3 according to reading interval (24 hours, 48 hours and 72 hours after UVA irradiation) were 3.4+/-2.9 J/cm2, 1.9+/-l.5 J/cm' and l. 7+1, 2/cm, respectively. 4 In the cases of oral administration of 8-MOP, MPDs of group 3 according to reading; interval as topical application of 8-MOP were 7.1+/-2.3 J/cm, 4.4+/-1.1 J/ cm2 and 4.2+/-l.2 J/cm2, respectively. 5 MPL)s accarding to the skin types as follows; (waiting time; 2 hours, read- ing interval; 48 hours) a. In the case of topical application of 8-MOP, MPDs of the skin type ]II, 1V and V were 0.9+/-0.5 J/cm2, 1.8+/-1.1 J/cm2 and 3.0+/-l.3 J/cm2 respectively. b. In the case of oral administration of 8-MOP, MPDs of skin type g, W and were 3.5+/-1.1 J/cm2, 4.7+/-1.3 J/cm2 and 6.9+/-l.8 J/cm2, respectively.
Administration, Oral ; Humans ; Male ; Methoxsalen ; Skin ; Skin Diseases

A 68-year-old male patient who was diagnosed as cutaneous mycosis fungoides with plaques, nodules and tumor has been treated with photochemotherapy. Oral methoxsalen followed by ultraviolet light(PUVA) resulted in clinical and histopathologic improvement of skin lesions. Photochemotherapy units consists of boxes with 12 UVA lamps. The initial dose was 8. 4 joules/cm2. The maintenance dose was 10. 5 joules/cm2. The total dose at present time is 1203. 82 joules/cm2. We prppose that PUVA therapy may be a valuable therapeutic regimen for mycosis fungoides.
Aged ; Humans ; Male ; Methoxsalen ; Mycosis Fungoides* ; Photochemotherapy* ; PUVA Therapy ; Skin

BACKGROUND: The PUVA therapy of psoriasis is a very effective therapeutic modality that combines the action of light and drugs. Generally the conventional PUVA therapy based on patient's skin type is used in Korea. But there are many reported that conventional PUVA therapy is not suitable in several instances including the determination of oral 8-methoxypsoralen(8-MOP) dose, initial and incremental UVA dose and so on. OBJECTIVE: The purpose of this study is to establish a new protocol of PUVA therapy that is photomedically acceptable. METHOD: From 1997 to 2001, twenty psoriasis patients of moderate to severe grade who visited our clinic, were treated with PUVA therapy. Initial UVA dose was the same as MPD of each patient and proportion of weekly incremental UVA dose was 20% added to previous dose. All patients received PUVA therapy twice a week. The 8-MOP dose was determined by body surface area. RESULT: Total of 8 patients were skin type III, and 12 patients were skin type IV. The average of initial MPD in skin type III was 1.75J/cm2(0.5~2.5J/cm2) and skin type IV was 3.25J/cm2(2.5~4.5J/cm2). The average number of treatments to the end of therapy were 13.63(10~16) in skin type III, and 12.5(8~18) in skin type IV. The total cumulative UVA dose was 44.73J/cm2(30~68.2J/cm2) in skin type III, and 67.98J/cm2(31.6~109J/cm2) in skin type IV. CONCLUSION: The excellent effectiveness and safety of our new PUVA protocol have been demonstrated. We conclude that this PUVA protocol is a very effective, safe, and efficient method for the treatment of psoriatic patients.
Body Surface Area ; Humans ; Korea ; Methoxsalen ; Psoriasis* ; PUVA Therapy* ; Skin

BACKGROUND: Psoralen has been used in the treatment of certain hypojigmentary disorders with UVA or solar irradiation. However trecent report proposed the actions of psiralens are direct and do not require the presence of ultraviolet light. The report also suggested that tze specific receptors other than DNA would be present. OBJECTIVE: This study was done ta identify the effects of 8-methoryporalen(8-MOP) on the proliferation and melanization of cultured normal human melanocytes without UVA. METHODS: Melanocytes were cultured in melanocyte culture medium neluding 16% or 5% FBS. We added 8-MOP by their concentrations from 10 M to 10 M. After 8 hours treatment, we investigated the melanocytes proliferation and Lhe melanin contents. RESULTS: We could not detecet any significant differences of melanoytes proliferation and melanin contents between the control end experimental groups. CONCLUSION: There were no effect on the proliferation and the milanization of cultured normal human melanocytes with 8-MOP only.
DNA ; Ficusin ; Humans* ; Melanins ; Melanocytes* ; Methoxsalen ; Ultraviolet Rays