Standardization of skin cleansing in vivo: part II. Validation of a newly developed Automated Cleansing Device (ACiD).

BACKGROUND: Skin cleansers for occupational use are manufactured for different types and degrees of soiling without common, legally binding requirements for product testing. This leads to different, manufacturer-specific test methods and a lack of comparable information on skin cleansing products. OBJECTIVES: The aim of this investigation was to validate a newly developed standardized automated cleansing device (ACiD) for in vivo evaluation of industrial skin cleansers. METHODS: Two ACiD were tested regarding the intra- and inter-device specific reproducibility of test results. RESULTS: Skin cleansing process carried out by the three independent washing modules which constitute an ACiD-unit and two separate ACiD-units led to highly comparable results. There was no significant difference between the washing modules or between the two separate ACiD-units detected. Only different parameter settings resulted in significantly different detergency. CONCLUSIONS: Intra- and inter-device specific test results of an in vivo model of skin cleansing using the automated cleansing device (ACiD) were reproducible. The long-term aim is a standardized classification of occupational skin cleansing products comparing their skin cleansing effectiveness in relation to their skin irritancy. This might then provide the basis for a rational specific product selection by consumers and may be used as a tool for future product development by manufacturers.

Standardization of skin cleansing in vivo: part I. Development of an Automated Cleansing Device (ACiD).

BACKGROUND: To date, there are no legally binding requirements concerning product testing in cosmetics. This leads to various manufacturer-specific test methods and absent transparent information on skin cleansing products. A standardized in vivo test procedure for assessment of cleansing efficacy and corresponding barrier impairment by the cleaning process is needed, especially in the occupational context where repeated hand washing procedures may be performed at short intervals. METHODS: For the standardization of the cleansing procedure, an Automated Cleansing Device (ACiD) was designed and evaluated. Different smooth washing surfaces of the equipment for ACiD (incl. goat hair, felt, felt covered with nitrile caps) were evaluated regarding their skin compatibility. RESULTS: ACiD allows an automated, fully standardized skin washing procedure. Felt covered with nitrile as washing surface of the rotating washing units leads to a homogenous cleansing result and does not cause detectable skin irritation, neither clinically nor as assessed by skin bioengineering methods (transepidermal water loss, chromametry). CONCLUSIONS: Automated Cleansing Device may be useful for standardized evaluation of the cleansing effectiveness and parallel assessment of the corresponding irritancy potential of industrial skin cleansers. This will allow objectifying efficacy and safety of industrial skin cleansers, thus enabling market transparency and facilitating rational choice of products.

[Recall dermatitis caused by re-exposure to docetaxel following irradiation of the brain. Case report and review of the literature]. / Recall-Dermatitis durch Docetaxel-Reexposition nach Gehirnbestrahlung. Fallbeobachtung und Literaturübersicht.

BACKGROUND: Together with radiation therapy the taxanes Paclitaxel and Docetaxel are more and more integrated into multimodal therapy regimens concerning breast- and lung cancer as well as squamous cell carcinoma of the head and neck. Especially in palliative situations we have to be aware of increasing side effects caused by interaction of the different treatment components. Therefore we report on a severe recall dermatitis that occurred in two breast-cancer patients following irradiation of the brain and reexposition to Docetaxel. PATIENTS AND METHOD: From January until March 1999 two female patients suffering from metastatic breast cancer and newly diagnosed cerebral metastases respectively carcinomatous meningitis underwent irradiation of the whole brain (2 Gy 5 days/week up to a reference dose of 50 Gy) in our department. Both patients had several courses of Docetaxel (Taxotere) 30 mg/m2 BSA weekly respectively 100 mg/m2 BSA/month since October and November 1998. After completion of radiotherapy chemotherapy with Docetaxel was continued. RESULTS: Both patients tolerated Docetaxel well before and during radiotherapy. However, after having finished irradiation of the brain and receiving Docetaxel again a severe erythema of the irradiated skin and large areas of moist epitheliolysis with crust occurred (CTC grade IV). CONCLUSION: The dermatitis related to irradiation and reexposition to Docetaxel observed in our two cases is interpreted as a recall reaction. The basic initiating pathologic mechanism has not been solved completely. Further investigation is needed to find out how the taxanes can be used in combination radiochemotherapy regimens without causing severe toxicity to the irradiated skin or mucosa.

Fluorescent derivatives of bile salts. III. Uptake of 7 beta-NBD-NCT into isolated hepatocytes by the transport systems for cholyltaurine.

Uptake of 7 beta-NBD-NCT ([N-[7-(4-nitrobenzo-2-oxa-1,3-diazol)]-7 beta-amino-3 alpha,12 alpha-dihydroxy-5 beta-cholan-24-oyl)-2'-aminoethanesulfonate) in isolated rat liver hepatocytes occurs by saturable transport without being superimposed by simple diffusion. The dependency of flux rate of uptake on the concentration of 7 beta-NBD-NCT in the presence of Na+ (143 mM) and with Na+ depletion (1 mM) is best described by the assumption of two simple transport systems. Maximal flux rates of uptake Jn and half-saturation constants KT for 7 beta-NBD-NCT are in presence of Na+ for transport system 1 J1(Na+ 143) = 0.15 +/- 0.03 nmol/(min.mg protein) and KT1(Na+ 143) = 3.5 +/- 0.5 microM and for transport system 2 J2(Na+ 143) = 1.0 +/- 0.1 nmol/(min.mg protein) and KT2(Na+ 143) = 190 +/- 25 microM, and in case of Na+ depletion J1(Na+ 1) = 0.1 +/- 0.03 nmol/(min.mg protein), KT1(Na+ 1) = 3.0 +/- 0.5 microM, and J2(Na+ 1) = 0.85 +/- 0.9 nmol/(min.mg protein) and KT2(Na+ 1) = 195 +/- 27 microM. Uptake of 7 beta-NBD-NCT by both transport systems is competitively inhibited by cholyltaurine in the presence of Na+ and with Na+ depletion. Two transport systems are likewise involved in the uptake of cholyltaurine in the presence of Na+ as well as in case of Na+ depletion. Their kinetic parameters are in presence of Na+ J'1(Na+ 143) = 1.55 +/- 0.14 nmol/(min.mg protein) and K'T1(Na+ 143) = 16.1 +/- 3.0 microM, and J'2(Na+ 143) = 0.51 +/- 0.05 nmol/(min.mg protein) and K'T2(Na+ 143) = 38.0 +/- 4.1 microM, and in case of Na+ depletion J'1(Na+ 1) = 0.10 +/- 0.02 nmol/(min.mg protein), K'T1(Na+ 1) = 7.7 +/- 1.2 microM, and J'2(Na+ 1) = 0.40 +/- 0.03 nmol/(min.mg protein) and K'T2(Na+ 1) = 41.0 +/- 4.2 microM. Uptake of cholyltaurine by both transport systems is competitively inhibited by 7 beta-NBD-NCT in the presence of Na+ as well as in case of Na+ depletion. In both cases the inhibition constants are practically identical with the KT values for uptake of 7 beta-NBD-NCT. Photoaffinity labeling of isolated hepatocytes using 7,7-ACT (400 microM) resulted in the irreversible inhibition of uptake of both bile salts to similar extents, confirming the kinetic data that 7 beta-NBD-NCT is a true analogue of cholyltaurine.