UV-induced free radicals in the skin detected by ESR spectroscopy and imaging using nitroxides.

Reactive free radicals and reactive oxygen species (ROS) induced by ultraviolet irradiation in human skin are strongly involved in the occurrence of skin damages like aging and cancer. In the present work an ex vivo method for the detection of free radicals/ROS in human skin biopsies during UV irradiation is presented. This method is based on the Electron Spin Resonance (ESR) spectroscopy and imaging and uses the radical trapping properties of nitroxides. The nitroxides 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO), 3-Carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCM), and 3-Carboxy-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCA), were investigated for their applicability of trapping reactive free radicals and reactive oxygen species in skin during UV irradiation. As a result of the trapping process the nitroxides were reduced to the EPR silent hydroxylamins. The reduction rate of TEMPO was due to both the UV radiation and the enzymatic activity of the skin. The nitroxides PCM and PCA are sufficiently stable in the skin and are solely reduced by UV-generated free radicals/ROS. The nitroxide PCA was used for imaging the spatial distribution of UV-generated free radicals/ROS. As a result of the homogeneous distribution of PCA in the skin, it was possible to estimate the penetration of UVA and UVB irradiation: The UV irradiation decreased the PCA intensity corresponding to its irradiance and penetration into the skin. This reduction was shown to be caused mainly by UVA radiation (320-400 nm).

SURF_ER--surface electron spin resonance (ESR) of the surface domain of large objects.

SURF_ER is a method for spectral and spatial electron spin resonance measurements on the surface of large objects which extension is only restricted by the width of the pole gap of the magnet and the homogeneity of the magnetic field and not by the cavity dimensions. The application of several techniques like SURF_ER for spectroscopic measurements, SURF_ERM for spatial scanning and SURF_ERI for spatial measurements of the depth of the surface region are discussed and represented for the skin of a human being as an example.

Electron paramagnetic resonance for everybody--MICROspec-X--a new class of electron paramagnetic resonance spectrometer.

The electron paramagnetic resonance spectroscopy is the only method for detecting free radicals. Free radicals have an increased importance in our daily life. A small transportable EPR spectrometer is presented for the popularisation of the EPR method. The technical construction and some applications are illustrated which show the usability of the spectrometer.

[Primary manifestation of lymphogranulomatosis in the soft tissue of the orbita (author's transl)]. / Primärmanifestation einer Lymphogranulomatose im Weichteilgewebe der Orbita.

In the paper presented here a rare of a lymphogranulomatosis in the soft tissue of the orbita is described. The Hodgkin's disease was preceded by a granulomatous inflammatory reaction in the right frontal sinus which was considered to be related to malignant midline reticulosis. A relation between both the diseases is suggested.

[The reliability of audiometry based on conscious orientation of the hearing impaired child (author's transl)]. / Die Zuwendungsaudiometrie und ihre Zuverlässigkeit in der Aussagekraft für die Einschätzung hörgeschädigter Kinder.

The authors present the audiometric procedure for hearing impaired children, which has been developed and performed routinely for some years by the Department of Audiology in the ENT-Clinic of the Friedrich-Schiller-University Jena. Problems of children's audiometry are discussed. The procedure developed, is based on the children's conscious orientation to the source of sound which can regularly be registered especially in children of the age from 5 or 6 months to 3 or 4 years. The threshold provoking orientation is 45 to 50 dB (absolute). The results gained by the method described are compaired with those which were obtained 4 to 9 years later in 41 subjects suffering from heredodegenerative hearing loss. A coefficient of correlation r = 0.77 was found, indication a very near correlation of results for both procedures. When compaired to ERA, the test presented is simple to perform and is though to be very valuable for praxis. The orientation audiometry is more exact than the test of subjective audiometry and various procedures based on acoustical reflexes, too.