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In this case report we describe the development in the cerebellopontine angle of a very rare tumor, ceruminous adenoma. In the few cases described in the literature this tumor occurred in the external acoustic meatus. In four cases it developed in the cerebellopontine angle by infiltration of the petrous bone or by subcutaneous spread. In the present case no connection was found between the cerebellopontine angle and the external acoustic meatus. The most likely pathogenetic hypothesis in this case is that of a tumor of dysembryogenetic origin.

The toxic effects of Triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) on morphology and sexual and asexual reproduction of C. ehrenbergii were examined. In addition, the genotoxic effects of Triclosan were evaluated on the same alga using the microgel electrophoresis test, also-called Comet assay. Increasing Triclosan concentrations in the range 0.125-5 mg L-1 did not affect size and shape of the cells but had relevant effects on both chloroplast morphology and dimension. Triclosan inhibited the vegetative growth of C. ehrenbergii at 0.5 mg L-1. The effects on sexual reproduction indicate that the number of C. ehrenbergii zygospores was significantly reduced by the application of 0.937 mg L-1. The Comet assay showed that Triclosan treatments led to a dose-dependent DNA damage of C. ehrenbergii; 0.25 mg L-1 caused significant genotoxic effects and higher concentrations irreversibly altered the DNA strands. These results suggest that C. ehrenbergii could represent a useful organism to evaluate the whole toxicity of pharmaceuticals and personal care products (PPCPs), giving valuable information for a risk assessment. (c) 2005 Elsevier B.V. All rights reserved.

Amoxicillin is a widely used penicillin-like antibiotic, and due to its presence in several effluents of Italian STPs, its environmental fate along with its toxicity toward simple organisms have been investigated in model conditions. The present study shows that under abiotic conditions both hydrolysis and direct photolysis could be responsible for the transformation and removal of amoxicillin in aquatic environment, especially in slightly basic media. Quantum yields for the solar direct photolysis have been calculated along with kinetic constants and half-life times. Indirect photolysis experiments in the presence of natural photosensitizers such as nitrate ions and humic acids indicate that nitrate ions have no influence on the photodegradation rate of amoxicillin, while humic acids are able to enhance it. Standard batch experiments have been also performed under biotic conditions. The results indicated that also biodegradation on activated sludge is an effective pathway through which amoxicillin can be removed from the aquatic environment. Rate constants for biodegradation and adsorption have been calculated by applying simple pseudo-first-order kinetic models. Algal bioassays indicate that, in the range of concentrations from 50 ng/L to 50 mg/L, amoxicillin is not toxic toward eucariotic organisms such as the Chlorophyceae Pseudokirkneriella subcapitata and Closterium ehrenbergii and the Bacillariophyceae Cyclotella meneghiniana, but it shows a marked toxicity toward the Cyanophyta Synechococcus leopolensis.