Biomaterial Database

DNA in psoriatic epidermis. 1979

J Sondergaard, and A Lerche, and V Bohr, and V Leik, and S Wadskov

An electron microscopic technique has been used to visualize crosslinks after total denaturation on DNA isolated from epidermis and dermis in patients with psoriasis treated with 8-methoxypsoralen (8-MOP) and irradiation with ultraviolet light at 360 nm (PUVA treatment). This technique facilitated accurate measurements of the number and density of DNA interstrand crosslinks. 30 biopsies from 14 patients were studied and a total of 9503 DNA molecules were scored in the electron-microscope, 6 patients were treated topically with 8-MOP and 10 were on systemic treatment. Two of the patients on topical treatment had previously been on systemic treatment. 1% of all DNA molecules contained 3 or more cross-links. The overall frequency of cross-links was almost identical in the epidermis (1.1%) and in the dermis (0.9%) and, furthermore, virtually the same in patients on topical and systemic PUVA treatment. The total number of crosslinks was of the same magnitude as that previously found in normal human skin. (V. Bohr et al., Acta Dermatovener, in press.) No significantly increased damage of the genetic material (DNA) was demonstrated in our study as a consequence of the PUVA treatment using 8-MOP. We have previously shown (V. Bohr & A. Lerche, Biochim Biophys Acta, in press) that 8-MOP induced crosslinks after irradiation at 360 nm in an in vitro system of pure DNA. In this system a correlation was established between the density of crosslinks formed and irradiation time, concentration of 8-MOP, and irradiation intensity.

UI	MeSH Term	Description	Entries
D008730	Methoxsalen	A naturally occurring furocoumarin compound found in several species of plants, including Psoralea corylifolia. It is a photoactive substance that forms DNA ADDUCTS in the presence of ultraviolet A irradiation.	8-Methoxypsoralen,Ammoidin,Xanthotoxin,8-MOP,Deltasoralen,Dermox,Geroxalen,Meladinina,Meladinine,Meloxine,Methoxa-Dome,Méladinine,Oxsoralen,Oxsoralen-Ultra,Puvalen,Ultramop,8 MOP,8 Methoxypsoralen,8MOP,Methoxa Dome,Oxsoralen Ultra
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D010778	Photochemotherapy	Therapy using oral or topical photosensitizing agents with subsequent exposure to light.	Blue Light Photodynamic Therapy,Photodynamic Therapy,Red Light PDT,Red Light Photodynamic Therapy,Therapy, Photodynamic,Light PDT, Red,PDT, Red Light,Photochemotherapies,Photodynamic Therapies,Therapies, Photodynamic
D011564	Furocoumarins	Polycyclic compounds consisting of a furan ring fused with coumarin. They commonly occur in PLANTS, especially UMBELLIFERAE and RUTACEAE, as well as PSORALEA.	Furanocoumarin,Furanocoumarins,Furocoumarin,Psoralens,Angelicins
D011565	Psoriasis	A common genetically determined, chronic, inflammatory skin disease characterized by rounded erythematous, dry, scaling patches. The lesions have a predilection for nails, scalp, genitalia, extensor surfaces, and the lumbosacral region. Accelerated epidermopoiesis is considered to be the fundamental pathologic feature in psoriasis.	Palmoplantaris Pustulosis,Pustular Psoriasis of Palms and Soles,Pustulosis Palmaris et Plantaris,Pustulosis of Palms and Soles,Psoriases
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D004817	Epidermis	The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012867	Skin	The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.
D014467	Ultraviolet Therapy	The use of ultraviolet electromagnetic radiation in the treatment of disease, usually of the skin. This is the part of the sun's spectrum that causes sunburn and tanning. Ultraviolet A, used in PUVA, is closer to visible light and less damaging than Ultraviolet B, which is ionizing.	Actinotherapy,Therapy, Ultraviolet,Actinotherapies,Therapies, Ultraviolet,Ultraviolet Therapies