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The emergence of methicillinresistant coagulasenegativeStaphylococcusas a major bacterial pathogen in neonatal intensive care units has stimulated interest in the epidemiology of spread of the organism. During a 12month “epidemic” of bacteremias with methicillinresistant coagulasenegativeStaphylococcuswe compared the characteristics of bacteremic and personnel nasallycarried strains by traditional and biomolecular methods. Sixtytwo percent of neonatal intensive care unit nurses were colonized with methicillinresistant coagulasenegativeStaphylococcuswith similar speciation to bacteremic strains. Inspection of plasmid profiles revealed a moderate degree of similarity between bacteremic and colonizing strains although genomic DNA restriction patterns showed diversity. Ribotype patterns were highly conserved 90 in personnel strains. A 2.6kilobase plasmid DNA probe hybridized to similarly sized plasmids and larger plasmids in onehalf of the strains. We hypothesize that related methicillinresistant strains may be transferred among personnel and neonates in the neonatal intensive care unit. Epidemiologic studies of coagulasenegative staphylococci should consider multiple molecular techniques to relate strains.

N-(n-Propyl)-, N-(n-butyl)-, and N-(n-amyl)-N-dithiocarboxy-d-glucamine were newly synthesized by (a) addition of each n-alkylamine to glucose, (b) high-pressure catalytic reduction of each glucosamine thus formed to the corresponding glucamine, and (c) reaction of the resultant secondary amines with CS2 to form the dithiocarboxy derivatives. Each compound was evaluated as an antagonist of acute cadmium (Cd) toxicity and as a complexing agent for intracellular metallothionein-bound Cd (Cd-MT) in mice. N-Benzyl-N-dithiocarboxy-d-glucamine (BDCG) was used as a positive control compound. Each congener afforded partial or complete protection against the lethal effects of 10.0 mg/kg CdCl2·2.5 H2O, and retarded accumulation of Cd in livers and kidneys when given 2 h after the acutely toxic dose of Cd. Each derivative was also effective in mobilizing Cd from MT-bound sites in livers and kidneys of mice which had received a sub-lethal dose of CdCl2 along with 109CdCl2 2 weeks earlier. Excretion of mobilized Cd was almost exclusively by the fecal route. Potency of the analogs, as well as the octanol/aqueous partition coefficients, increased with the overall length of the N-(n-alkyl) carbon chain. Each compound readily complexed Cd from partially purified Cd-MT in vitro. Serum Cd from mice treated with BDCG was associated principally with proteins of high molecular weight.

Yoshi-864 extends markedly the survival times of mice bearing L1210 leukemia or Ehrlich ascites carcinoma. Busulfan, with methanesulfonate leaving groups identical with those of Yoshi-864, is without effect. Tumor cells from mice bearing the Ehrlich tumor and treated with Yoshi-864 have a persistent reduction in ability to synthesize DNA. Synthesis of DNA in cells from mice treated with busulfan is moderately suppressed at 48 hr after treatment, but returns virtually to the control value at 72 hr.

Dichloro (4,5–dimethyl–o–phenyl–enediamine–N,N′)platinum (II) (DDPP) was synthesized by the reaction of 4,5–dimethyl–o–phenylenediamine with potassium tetrachlo–roplatinate. The resulting compound extended up to 176% the survival times of BALB/c mice bearing the Ehrlich ascites tumor and up to 74% the survival times of BDF1mice bearing the L1210 leukemia. In studies using Ehrlich ascites tumor cells in vitro, DDPP was found to be a potent inhibitor of synthesis of DNA, RNA, and protein; the concentrations which conferred 50% inhibition following 1.5 hr of incubation with the compound were 3 × 10-5to 5 × 10-5M. Inhibition of nucleic acid and protein synthesis in vitro, once established, was not ameliorated by washing the cells with fresh medium devoid of DDPP. Cellular DNA, RNA, and protein, each appropriately labeled with a radioisotopically labeled precursor, became more acid–soluble upon incubation of the cells in vitrowith DDPP. The rate of loss of viability of cells incubated in vitrowith DDPP, as assessed by the trypan blue exclusion method, was found to be considerably greater than the rate obtained upon incubation of cells with an equivalent concentration of cis–dichlorodiammineplatinum(II).

Alanosine is an inhibitor of glutamic acid carboxy-lyase (C-L) of bacterial origin, but not of those from squash and rat brain. Its action is competitive in respect to glutamic acid, but noncompetitive in respect to pyridoxal phosphate. Other bacterial amino acid C-L's tested, while sensitive to hydroxylamine, are not inhibited by alanosine.