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The tetrasaccharide hapten released from the glycopeptidolipid (GPL) antigen of Mycobacterium avium serovar 20 has been characterized as O-(2-O-methyl-alpha-D-rhamnopyranosyl)-(1----3)-O-(2-O-methyl-alpha-L- fucopyranosyl)-(1----3)-alpha-L-rhamnopyranosyl-(1----2)-6-deoxy-L-talos e. Syntheses are reported of allyl glycosides of the outer disaccharide unit of this hapten, O-(2-O-methyl-alpha-D-rhamnopyranosyl)-(1----3)-2-O-methyl-alpha-L-fu copyranose , and also of the outer di- and tri-saccharide units of the GPL antigen of M. avium serovar 14, O-(N-formyl-alpha-L-kansosaminyl)-(1----3)-2-O-methyl-alpha-D-rham nopyranose and O-(N-formyl-alpha-L-kansosaminyl)-(1----3)-O-(2-O-methyl-alpha-D- rhamnopyranosyl)-(1----3)-2-O-methyl-alpha-L-fucopyranose. The key steps in the latter synthesis involve the preparation of allyl 4-azido-4,6-dideoxy-3-C-methyl-2-O-methyl-alpha-L-mannopyranoside as a precursor for the N-formylkansosamine unit, followed sequentially by conversion into and use of a trichloroacetimidate as glycosyl donor for di- and tri-saccharide formation, O-deacylation, reduction, and N-formylation. The allyl glycosides, representative of the haptens from both serovars, have been converted into neoglycoproteins (NGPs) and their serological activities have been compared in the light of the structural relationship between them.

Neoglycoproteins bearing key glycosyl substituents of several glycopeptidolipid antigens of pathogenic Mycobacterium species have been synthesized. Allyl glycosides of the terminal 6-deoxyhexose-containing units of the antigens were prepared, with appropriate ether and ester substituents in place. Ozonolysis of the allyl glycosides was then followed by reductive coupling with epsilon-amino groups of lysine residues in bovine serum albumin, using sodium cyanoborohydride at pH 7.8. The resulting neoglycoproteins emulated the antigenicity of the native molecule in several serological tests.

Human transitional cell carcinoma was successfully grown in short-term tissue culture in 17 of 29 specimens collected (58 per cent). Morphologic parameters of the explants were studied with light and transmission electron microscopy before and after incubation with either thiotepa or 5-fluorouracil. Thiotepa was found to produce marked acantholysis in 43 per cent of those studied. We postulate that thiotepa acts primarily through breakdown of cell adherence. Changes found with 5-fluorouracil were primarily confined to the nucleus.

Forty male rats were divided into four groups. Group I served as control. Group II received 1 mg. lead injected into the prostate; Group III received 1 mg. cadmium chloride; and Group IV received 0.5 mg. lead acetate and 0.5 mg. cadmium chloride. Results indicated that lead caused stone formation in the bladder and calcification of both bladder and prostate; cadmium caused reduction in size and weight of prostate, and histological observation showed marked atrophy of the gland, cuboidal epithelium, and squamous metaplasia in the acini of the prostate; there was no synergistic effect of lead acetate and cadmium chloride when combined at the level administered to Group IV.

A new pregnane derivative designated as bregenin [1] has been isolated from the dried twigs of Sarcostemma brevistigma. Chemical and spectroscopic evidence is consistent with the structure 3 beta, 14 beta, 16 alpha, 17 beta tetrahydroxypregn-5-en-20-one for bregenin.