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Background: Various cutaneous toxicities under chemotherapy indicate a local effect of chemotherapy by secretion after systemic application. Here, changes in the fluorescence and Raman spectral properties of the stratum corneum subsequent to intravenous chemotherapy were assessed. Methods: Twenty healthy subjects and 20 cancer patients undergoing chemotherapy were included. Measurement time points in cancer patients were before the first cycle of chemotherapy (Tbase) and immediately after intravenous application of the chemotherapy (T1). Healthy subjects were measured once without any further intervention. Measurements were conducted using an individually manufactured system consisting of a handheld probe and a wavelength-tunable diode laser-based 488 nm SHG light source. Hereby, changes in both skin fluorescence and shifted excitation resonance Raman difference spectroscopy (SERRDS) carotenoid signals were assessed. Results: Healthy subjects showed significantly (P

Hintergrund: Im menschlichen Organismus stellen Antioxidantien einen wichtigen Schutzmechanismus gegen die destruktiven Effekte von freien Radikalen dar. Diese können durch diverse interne und externe Einflüsse entstehen, wie z.B. UV- und Infrarot-Strahlung, chemische Noxen, Infektionskrankheiten oder Nikotin- und Alkoholabusus. Ziel dieser Arbeit war es, den Einfluss von individuellen Lebensgewohnheiten, wie Ernährungs und Stressfaktoren, auf das antioxidative Potential (AOP) der Haut herauszustellen. Auch mögliche Unterschiede verschiedener ethnischer, Alters- und sozialer Gruppen sollten hierbei untersucht werden. Material und Methoden: Hierfür wurden an gesunden Probanden mit unterschiedlichem sozialen und ethnischen Hintergrund die Carotinoidkonzentrationen in der Haut bestimmt. Die Messungen wurden mittels eines mobilen, miniaturisierten, reflektionsspektroskopischen Messgeräts durchgeführt und individuelle Daten zu Ernährungs- und Lebensgewohnheiten erfasst. In einem weiteren Schritt wurde im Rahmen einer klinischen Studie die topische Applikation von hoch konzentrierten Antioxidantien für die Prävention und Therapie des Hand- und Fuß-Syndroms bei Chemotherapiepatienten untersucht. Ergebnisse: Es konnte in den Studien gezeigt werden, dass vor allem eine gesunde Ernährung, reich an Obst und Gemüse sowie die Meidung von Stress für ein hohes AOP sehr wichtig sind. Bei dem AOP handelt es sich um einen multifaktoriell bedingten Prozess, der durch stimulierende, aber auch reduzierende Faktoren gekennzeichnet ist. Hierbei haben das Ernährungs- und Stressverhalten besonderes Gewicht. Individuelle Änderungen der Ernährungs- und Lebensweise können anhand der Carotinoide als Biomarker schnell und noninvasiv dargestellt werden. Darüber hinaus sind die Messungen sehr gut geeignet, um gesunden Probanden ein Biofeedback über ihre gegenwärtigen Lebens- bzw. Ernährungsgewohnheiten zu geben und zu einer gesünderen Lebensweise zu motivieren. Auch die klinische Anwendung einer Pflegesalbe mit hoch konzentrierten Antioxidantien zeigte sehr gute therapeutische und präventive Effekte gegen das Hand- und Fußsyndrom. Diskussion: Als schnelle, mobile und non-invasive Messmethode ist die Reflektionsspektroskopie gut geeignet, um das AOP in größeren Probandengruppen zu untersuchen. Sowohl die Bestimmung von kutanen Antioxidantien mittels der genannten Messmethode als auch die topische Anwendung von Antioxidantien können für die individuelle Gesundheitsförderung und Krankheitsprävention von effektivem Nutzen sein., Background: Antioxidants represent an important protective mechanism against the destructive effects of free radicals in the human organism. These can arise due to various internal and external influences, such as UV and infrared radiation, chemical toxicants, infectious diseases or nicotine and alcohol abuse. The aim of this study was to investigate the impact of individual lifestyle habits, such as diet and stress factors, on the antioxidant status of the skin. Furthermore possible differences between ethnical population groups, age and social groups were examined. Materials and Methods: For this purpose the cutaneous carotenoid concentration was determined in healthy volunteers of different social and ethnical background using a mobile, miniaturized measurement device based on reflection spectroscopy. Moreover individual data on dietary and lifestyle habits was assessed. In a further step, the clinical use of a topically applied cream containing highly concentrated antioxidants was investigated for treatment and prevention of palmar plantar erythrodysesthesia in patients receiving chemotherapy with pegylated liposomal doxorubicine. Results: It was shown that especially a healthy diet, rich in fruit and vegetables, and avoidance of stress are equally important for a high antioxidant status. The antioxidant status is a multifactorial process that is influenced by stimulating, as well as reducing factors. The nutritional and stress behavior is of particular importance. Individual changes in diet and lifestyle can quickly be shown by using the above mentioned non-invasive spectroscopic mean measuring carotenoids as biomarkers. In addition to that, the measurements are well suited to provide a biofeedback about present individual lifestyle and eating habits or even motivate to a healthier lifestyle. Furthermore the clinical application of a cream containing a high concentration of antioxidants showed positive therapeutic and preventive effects against palmar plantar erythrodysesthesia. Discussion: Due to its handiness, mobility and non-invasiveness, the used spectroscopic device is a well suited tool to investigate the antioxidant status in a larger amount of subjects. Both the determination of cutaneous antioxidants by means of the described method as well as the topical application of concentrated antioxidants can be effectively used for individual health promotion and disease prevention.

Hydrolytically polymerized poly(methyl-co-vinyl)siloxane is cross-linked by radically and dehydrolytically at elevated temperature. Peroxide-type thermal radical generator is found to cross-link the polymer at the vinyl and methyl pendant groups. In parallel, free silanol (Si-OH) end groups in the polymer also contribute to cross-linking by dehydrolytic polycondensation. By use of these two-fold cross-linking mechanisms, we were able to deposit highly cross-linked siloxane polymer film which provides excellent optical and electrical properties. Cured film of 500 nm thickness exhibited the pencil hardness of 9H on glass with > 95% visible light transmittance. These excellent features are applied to optical hard coating for flexible displays and touch panels. The cured film also exhibited excellent electric properties. The leakage current of the film is as low as that of CVD dielectric film, and the break down field is exceeded 3 MV/cm, which enabled the film to be applied to insulator in thin film transistor. We carried out analyses of the polymer in film and powder form with 13C- and 29Si-NMR MAS, FT-RAMAN and FTIR-ATR methods to investigate curing mechanism. The analysis results clearly indicated that the cured film contains unique Si-(CH)n-Si bonds generated by radical crosslinking, and all the Si-OH bonds are consumed by hydrolytic polycondensation as well. The Si-(CH)n-Si bonds are more rigid and less polar than Si-O-Si bond, which should be the major reasons that radical condensation remarkably reinforced the film. This radically and thermally cured poly(methyl-co-vinyl)siloxane film was applied to Mo-gate thin film transistor fabricated on glass as the gate insulator. The I-V characteristics from the transistor were equivalent to those made using CVD-SiN insulator.