Bioassay monitoring of waste PCB samples during chemical destruction treatments.

Capacitor oil samples (PCBs > 90%wt) were treated in a bench scale experiment to investigate the destruction of PCBs during chemical destruction processes (a catalytic hydrodechlorination treatment with palladium carbon and additional treatment with potassium tert-butyloxide). Using those results, this study confirmed the decrease of PCBs and other undesirable dioxin-like compounds such as PCDD/Fs in treated samples during the treatment. Dioxin-responsive chemical-activated luciferase expression (DR CALUX) AhR reporter gene bioassay was used to evaluate dioxin-like activity in the samples. During the treatment, the efficiency for PCB capacitor oil was around 99.99% or more in WHO-TEQ and CALUX-TEQ, whereas the sum of PCBs was reduced at a resulting efficiency of >99.9999%. In this study, a new cleanup procedure for separating PCBs from the mineral oil matrix was also developed for DR CALUX. The procedure consists of dimethylsulphoxide partitioning followed by silica gel-44% sulphuric acid reflux treatment and activated carbon chromatography. With the cleanup, CALUX-TEQ values were in good agreement with WHO-TEQ values and were as much as 3.3 times higher than WHO-TEQs for untreated/treated PCB-containing insulating oil samples. The DR CALUX results of mineral oil samples containing various PCB concentrations of 0.5-50 mg/kg (corresponding WHO-TEQs: 0.012-1.2 microg-TEQ/g) also correlated well with WHO-TEQs (CALUX-TEQ/WHO-TEQ ratio = 1.0-3.0), which was consistent with the theoretical quantification limit of the CALUX. These results supported the validity of the proposed clean-up method.

Primary poorly differentiated adenocarcinoma of the middle ear.

Adenocarcinoma of the middle ear is seldom encountered in clinical practice. In the past 20 years, nearly 20 cases of primary adenocarcinoma of the middle ear have been reported, and most cases of these tumors have been described without histologic presentation. To our knowledge, only one case of adenocarcinoma originating in the postoperative middle ear has been reported. We describe a case of primary poorly differentiated adenocarcinoma in the middle ear which was surgically treated for chronic otitis media 50 years ago. Planning diagnostic and therapeutic procedures in connection with middle ear tumors is also discussed.

A new gluco indole alkaloid, 3, 4-dehydro-5-carboxystrictosidine, from Peruvian Uña de Gato (Uncaria tomentosa).

A new gluco indole alkaloid, 3,4-dehydro-5-carboxystrictosidine, was obtained from Peruvian Uña de Gato (Cat's Claw, original plant: Uncaria tomentosa) together with two known gluco indole alkaloids. This compound was the first example of isolation of a gluco monoterpenoid indole alkaloid having a 3,4-dihydro-beta-carboline ring system from nature. A characteristic feature of the compound was the quick replacement of the methylene hydrogens on C-14 with deuterium that was observed when it was dissolved in CD3OD. We demonstrated a similar proton-deuterium exchange on a model compound, 1-methyl-3,4-dihydro-gamma-carboline, in CD3OD solution.

Malignant fibrous histiocytoma of the temporomandiblar joint. Report of a case.

A case of malignant fibrous histiocytoma of the temporomandibular joint in a 21-year-old Japanese female was presented. The patient died of the tumor with local aggressive growth but without any organ metastasis, despite the intensive treatment including radical operation of the tumor, irradiation, and chemotherapy. This case suggested that radical curative operation was the only method of the treatment for this tumor. The clinicopathological features of the tumor are discussed, making reference to the malignant fibrous histiocytoma.