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Review: 43 refs. [ABSTRACT FROM AUTHOR]

We present a diastereoselective synthesis of disubstituted cyclopentane 8 having a nitrogen-containing quaternary carbon center, which is found in axinellamine A ( 5) and related compounds. During this work, we found that the 1,3-dipolar cycloaddition product 24 immediately underwent intramolecular redox reaction at the newly formed morpholin-2-one moiety, thus affording disubstituted cyclopentane containing a tertiary amine ( 9) stereoselectively in good yield. The amine 9 was successfully converted into guanidine 31, which corresponds to 8, through iminium cation-enamine isomerization. [ABSTRACT FROM AUTHOR]

To examine whether cancer cell dissemination results from incisional biopsy, we tried to detect squamous cell carcinoma (SCC) cells in peripheral blood before and after incisional biopsy by means of cytokeratin 19 (CK19) reverse-transcriptase polymerase chain reaction (RT-PCR). The study population consisted of 20 patients with oral SCC; 10 were given incisional biopsies followed by radical excision (the incisional biopsy group), and the remaining 10 were treated by excisional biopsy alone (the excisional biopsy group). Ten non-oral cancer patients with benign oral lesions served as controls. Five-ml blood aspirates collected before and after incision were used for CK19 RT-PCR. Two (20.0%) of 10 patients from the incisional biopsy group were positive for CK19 transcripts in their peripheral blood drained 15 min after incision. In contrast, CK19 transcript was not detected either in the excisional biopsy group or in controls. Surgical invasiveness for oral cancer, including incisional biopsy, causes dissemination of cancer cells into circulation, resulting in increased risk of metastasis. [ABSTRACT FROM AUTHOR]