Identification of products formed during UV irradiation of tamoxifen and their use for fluorescence detection in high-performance liquid chromatography.

During the UV irradiation of tamoxifen, isomerization of the trans to the cis isomer takes place and consequently corresponding highly fluorescent phenanthrene derivatives are formed. Their formation can be used for the sensitive and selective detection of tamoxifen in high-performance liquid chromatography (HPLC). The structure of photoproducts was identified by 1H NMR spectroscopy, HPLC, gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Owing to the variety of products formed and the higher selectivity and fluorescence response, on-line postcolumn photocyclization is preferred to the precolumn mode. A chromatographic system for the separation of isomers and photoproducts is suggested.

[An unusual occurrence of spinaliomas in schnauzers]. / Neobvyklá incidence spinaliomu u kníracu.

This paper describes 17 cases of digital spinocellular carcinomas of the limbs of the schnauzer dogs (14 in males and 3 in females) which were diagnosed from July 1987 to the end of 1988. During comparison of the prevalence of these neoplasmas over the period 1975 to 1984, when 11 cases of spinaliomas were diagnosed in dogs, there is an uncommonly high and interesting incidence of these tumors in schnauzers. Spinaliomas were not diagnosed in other breeds and in other locations. We know of no other similar observation. The tumour had the appearance of a poorly mending wound or panaritium and they locally destroyed the digits of the affected individuals. Recurrence was observed once, metastases in lymphatic nodes or other tissues were not observed up to the present time. Histologically the tumors had the appearance of well differentiated spinocellular carcinomas with a fibro-producing and intensive inflammatory reaction. The sarcomatous appearance of the tumor parenchyma was sporadically observed. Lesions were indications for the amputation of the affected digits. As possible etiological factors the authors consider, besides traumatic influences of the overgrown claws, even hormonal and infectious influences.