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One-hundred-and-seventeen patients with histologically proven carcinoma of the gallbladder are reviewed. The majority of the patients presented with advanced disease with extension and metastasis to the liver and to lymph nodes along the common bile duct. Four patients had localized disease recognized at the time of operation; two were treated with cholecystectomy and two with cholecystectomy and hepatic resection. There were no five-year survivals among these patients. Fourteen patients had clinically inapparent carcinoma at the time of cholecystectomy; the diagnosis being established postoperatively by histologic examination of the excised gallbladder. There were two five-year survivors in this group of patients. Both survivors had early papillary carcinoma confined to the gallbladder wall. The remaining patients with inapparent carcinoma died within three years of the time of operation with recurrent carcinoma. The present report and review of the recent literature emphasizes the poor prognosis associated with carcinoma of the gallbladder. Even with apparently localized lesions, the survival rate is extremely poor. Extended resection, while not of proven value, may improve the survival rate.

The organization of proteins along DNA in chromatin of Saccharomyces cerevisiae (baker's yeast) was examined by analyzing the DNA and nucleoprotein products obtained after digestion of yeast nuclei with staphylococcal nuclease. Yeast DNA is digested in situ at regularly spaced cleavage sites about 160 Before the transcriptional apparatus of yeast can be related with certainty to that of higher cells, similarities in genome organization must be established. Interphase chromatin fibrils of higher eukaryotes have a "beaded string" structure consisting of repeated arrays of globular particles (about 100 A diameter) connected by thin nucleoprotein filaments (9-12). Nucleases cleave these interconnecting regions, producing individual "subunits" and larger oligomeric nucleoprotein units that can be readily isolated (12, 13). Subunits from higher eukaryotes contain two copies each of histones H2A, H2B, H3, and H4 associated with about 140 base pairs of DNA (12,14). Recent neutron diffraction studies (15) have confirmed earlier proposals (10, 11) that these histones form a "core" about which the unit length of DNA is wrapped. Lysine-rich histones HI (and H5 in erythrocytes) appear to be associated primarily with the "spacer" DNA, 30-60 base pairs long, between globular subunits (14,16,17).Yeast chromatin potentially may have a subunit structure since yeast nuclei contain several major basic proteins that electrophorese similarly to histones (18,19). In fact, staphylococcal nuclease digests yeast chromatin at discrete intervals, indicating that proteins are arranged along the DNA in-a periodic manner (18,20,21). However, some caution is warranted in interpreting these results because of reports that yeast lacks histones Hi and H3 (22) and that yeast ribosomal proteins may be coisolated with or otherwise mistaken for histones (23).As described below, we have confirmed the periodic structure of yeast chromatin and have isolated and partially characterized monomeric subunits and oligomer units from yeast that appear to be nearly identical to subunits from higher eukaryotes.MATERIALS AND METHODS Isolation and Digestion of Yeast Nuclei. Saccharomyces cerevisiae strain A8209B was obtained from Dr. Gerald Fink (Cornell University). Yeast cells and protoplasts were prepared as described by deKloet et al. (24). Prior to isolation of nuclei, protoplasts (OD6Wj nm = 1-1.5) were incubated for 45 min at 300 in 20 mM KH2PO4 (pH 6.2)/2 mM MgCl2/2% glucose/ 0.3% casamino acids/20% sorbitol to permit return to a metabolically active state (24). The protoplasts were then rapidly cooled to 40 and washed with cold 20% sorbitol. Nuclei were isolated (at 0-40) by a method modified slightly from that of Blobel and Potter (25). Protoplasts were washed once in TKMC buffer (50 mM Tris-HCI, pH 7.5/25 mM KCI/5 mM MgCI2/1 mM CaCI2) containing 0.25 M sucrose, then twice in the same solution containing 0.5% Triton X-100. The crude nuclear pellet was purified by centrifugation through dense sucrose in TKMC buffer plus 0.1 mM phenylmethylsulfo...

1,4-Oxazinone derivatives of the phenoxazinone chromophore in actinomycin D (AMD) have been synthesized by condensation of AMD with alpha-keto acids. By varying the starting alpha-keto acid, the substitutions on the oxazinone ring and, consequently, the lipophilicity of the molecule could be altered. These oxazinone derivatives revert to AMD in physiological media and it appears that these oxazinones are "depot" forms of AMD and possess physicochemical and DNA-binding properties which are significantly different from those of AMD. The oxazinones, which have bulky and lipophilic substituents at position 3, demonstrate more pronounced antitumor activity against P388 mouse leukemia and are less toxic than AMD.