SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Psoralen

29

Abstract The Goeckerman regimen, consisting of the application of crude coal tar combined with exposure to ultraviolet radiation, was formulated in 1925 for the treatment of psoriasis. While some centers have adapted the Goeckerman regimen for the treatment of eczema, there are no published reports of its efficacy in this condition. Here, we explain how the Goeckerman regimen has been modified for use in an eczema population at the University of California San Francisco (UCSF). We reviewed the treatment records of eczema patients treated with the modified Goeckerman regimen over a 6-year period at UCSF. We found that the Goeckerman regimen was effective in treating patients with severe baseline disease, inducing a mean remission period of 7.2 months. The treatment was tolerated well with mild folliculitis and occasional ultraviolet B phototoxicity noted as the only adverse reactions. Since the use of Goeckerman as a treatment for severe eczema is both effective and safe, it should be considered an excellent alternative or adjunct to the systemic therapies currently being used.

Concepts: Cancer, Ultraviolet, Electromagnetic spectrum, Sunlight, Eczema, Psoriasis, Psoralen, Coal tar

29

Abstract Background: Several treatment modalities had been used for the treatment of vitiligo but the optimal treatment has not yet been identified. Aim: To evaluate the efficacy and safety of intradermal injection of 5-flurouracil (5-FU) combined with narrow-band ultraviolet B (NB-UVB) as a treatment option for vitiligo. Patients and methods: The study included 60 vitiligo patients with overall symmetrical lesions affecting less than 30% of body surface area. For each patient, one side of the body was treated with NB-UVB alone (control side) while the other side was treated with NB-UVB therapy in addition to intradermal injection of 5-FU (50 mg/ml), 0.01-0.02 ml per injection with 1 cm apart in skin of vitiligo, every 2 weeks for 4 months. Results: The overall repigmentation was significantly higher in the 5-FU side compared with control side in all body parts (p < 0.001) except for the acral lesions where the difference was not significant (p = 0.561). No systemic side effects of 5-FU were detected, and the majority of the patients reported pain during injections. Conclusions: Intradermal 5-FU injection in combination with NB-UVB could be considered as a simple, safe, tolerable and cheap technique for treatment of vitiligo. It shortens the duration of NB-UVB therapy and improves the outcome, repigmentation. Longer follow-up is needed.

Concepts: Pharmacology, English-language films, Human skin color, Vitiligo, Psoralen

0

Transplantation of autologous cultured melanocytes as cell suspension has been used for the treatment of vitiligo. The recipient site is often prepared by laser-mediated dermabrasion. Such procedures encounter disadvantages including prolonged transplantation duration, unsecured cell adherence to lesional skin and potential scarring. To improve this, here we propose a method by preparing recipient sites before transplantation by psoralen and ultraviolet A (PUVA)-induced sunburn followed by transplanting cells with a chitosan-based melanocyte spheroid patch. We evaluated the method in nude mice. Application of methoxsalen-soaked filter paper on skin for 30 min followed by ultraviolet A exposure induced controlled sunburn blisters in 2 days. Upon transplantation, the blister roof could be quickly peeled off by a waxing patch. The chitosan membrane on which melanocytes were precultured into multicellular spheroids was transplanted with cells facing the skin. The chitosan patch adhered well to skin and secured the contact of melanocytes with the recipient site. One day later, melanocyte spheroids already detached from the chitosan membrane and adhered to the recipient skin. Our results suggest that the combination of chitosan-based melanocyte spheroid patch with epidermal ablation by PUVA-induced sunburn reaction can be a feasible method to facilitate melanocyte transplantation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018.

Concepts: Ultraviolet, Skin, Melanin, Blister, Sunscreen, Sun tanning, Melanocyte, Psoralen

0

Furocoumarins (psoralens and angelicins) have been already used under ultraviolet A light (UVA) for the treatment of skin diseases and cutaneous T-cell lymphoma. Besides their high anti-proliferative activity, some severe long-term side effects have been observed, for example genotoxicity and mutagenicity, likely strictly related to the formation of crosslinks. It has been demonstrated that blue light (BL) activation of 8-methoxypsoralen, an FDA-approved drug, leads to less mutagenic monoadducts in the DNA. So far, in this work the less toxic and more penetrating BL is proposed to activate 4,6,4'-trimethylangelicin (TMA), an already known UVA photoactivatable compound.

Concepts: DNA, Cancer, Mutation, Ultraviolet, Sunlight, Mutagen, Light therapy, Psoralen

0

Photosensitizers are used in the treatment of epidermal proliferation and differentiation disorders such as psoriasis and vitiligo. In the present studies, a ring-expanded carbon homologue of the linear psoralen (furo[3,2-g]benzopyran-7-one) class of photosensitizers, 4,10-dimethyl-2H,8H-benzo[1,2-b:5,4-b']dipyran-2-one (NDH2476), was synthesized and analyzed for biological activity. Following activation by ultraviolet light (UVA, 320-400 nm), NDH2476 was found to be a potent inhibitor of keratinocyte growth (IC50 = 9 nM). Similar derivatives methylated in the pyrane ring, or containing a saturated pyrane ring structure, were markedly less active or inactive as photosensitizers. NDH2476 was found to intercalate and damage DNA following UVA light treatment as determined by plasmid DNA unwinding and nicking experiments. Taken together, these data demonstrate that an intact furan ring in psoralen photosensitizers is not required for keratinocyte growth inhibition or DNA damage. Our findings that low nanomolar concentrations of a benzopyranone derivative was active as photosensitizer indicates that this or a structurally related compound may be useful in the treatment of skin diseases involving aberrant epidermal cell growth and differentiation. This article is protected by copyright. All rights reserved.

Concepts: DNA, Ultraviolet, Bacteria, English-language films, Psoriasis, Copyright, Light therapy, Psoralen

0

We report the case of a 59-year-old woman who simultaneously suffered from psoriasis and vitiligo. The depigmented areas were predominantly but not exclusively limited to current or former psoriatic plaques. These two diseases share many common features, e. g., both are T‑cell-mediated autoimmune diseases in which the Koebner phenomenon occurs. However, it is still not known whether the coincidence is random or significant. Prospective clinical and epidemiological research will hopefully reveal the association soon.

Concepts: Epidemiology, Disease, Infectious disease, Autoimmune disease, Autoimmune diseases, Psoriasis, Psoralen, Koebner phenomenon

0

Use of the 308 nm Excimer laser to treat hypopigmentation and vitiligo is usually superior to conventional ultraviolet (UV) therapy with regard to results and safety. It is particularly advantageous because specific areas of skin can be targeted without burdening the rest of the skin. Fewer sessions with lower cumulative doses are required. Various combination therapies can improve the outcome; selection criteria such as early initiation of treatment and more frequent sessions with shorter intervals make it easier to decide which patients should be treated and how to achieve the greatest benefit.

Concepts: Ultraviolet, Optical fiber, Laser, Therapy, Human skin color, Infrared, Excimer laser, Psoralen

0

Phototherapy is the cornerstone of treatment of vitiligo. The 308-nm excimer lamp (EL) induces T cell apoptosis and the stimulation of melanocyte proliferation. Khellin is a furanochromone with a chemical structure close to psoralens. The objective of the study was to evaluate the safety and efficacy of 1-year treatment of recalcitrant vitiligo with a combination of 308-nm EL and khellin.

Concepts: Apoptosis, Cytotoxic T cell, Vesicle, Psoralen

0

The new coumarin 1, yuganin A (7-methoxy-8-((1S,2S)-1,2,3-trihydroxy-3-methylbutyl)-2H-chromen-2-one) along with nine known coumarins, heraclenol 3'-O-β-D-glucopyranoside (2), oxypeucedanin hydrate 3'-O-β-D-glucopyranoside (3), heraclenol (4), oxypeucedanin hydrate (5), osthole (6), oxypeucedanin (7), heraclenin (8), isoimperatorin (9), imperatorin (10) and the disaccharide sucrose (11), have been isolated from the roots of Prangos pabularia, and the structures of these isolated compounds were elucidated by spectroscopic means, especially, UV, HR-ESIMS, and 1D and 2D NMR spectroscopy. Furthermore, the anti-melanogenic effect of yuganin A and its inhibitory effect on B16 cells were evaluated. Yuganin A may be useful in the treatment of hyperpigmentation and as a skin-whitening agent in the cosmetics industry.

Concepts: Spectroscopy, Glucose, NMR spectroscopy, Cosmetics, Carbohydrate, The Roots, Coumarin, Psoralen

0

Hand eczema is a common inflammatory dermatosis that causes significant patient morbidity. Symptoms such as pain, itch and localised swelling contribute to disruption of activities of daily living, lack of sleep, and missed days from work. The aetiology is often multifactorial. Previous studies comparing psoralen ultraviolet A (PUVA) and narrowband ultraviolet B (NBUVB) have been small, non-randomised and retrospective.

Concepts: Ultraviolet, Eczema, Psoriasis, Mutagen, Psoralen