In conjunction with Professor G. Wald, we recently investigated the isomers of vitamin A, present in the marine euphausiid Crustacea Meganyctiphanes norvegica (M. Sars) and Thysanoessa raschii (M. Sars) and found that 1 1 4 s vitamin A (neo-b vitamin A) was the predominant form, comprising some 80-90y0 of the total (Plack, Fisher, Henry & Kon, 1956; Wald & Brown, 1956-7; Fisher, Kon & Plack, 19...

The binding of the antitumor drug cis-dichlorodiammineplatinum(II) and its inactive trans isomer with the nucleosome core particle has been investigated. Kinetic studies show that platinum binding increases with incubation time, from a few bound platinum atoms per nucleosome core in the first 0.5 hr to 40-50 after 40 hr. There is no crosslinking or dissociation of nucleosome cores upon platinum...

Three Angus steers (410 kg) cannulated in the proximal duodenum were used in a replicated 3 x 3 Latin square to evaluate the effects of dietary lipid level and oil source on ruminal biohydrogenation and conjugated linoleic acid (CLA) outflow. Dietary treatments included: 1) typical corn (TC; 79.2% typical corn), 2) high-oil corn (HOC; 79.2% high-oil corn), and 3) the TC diet with corn oil added...

Of late there has been a great deal of interest in special Lagrangian submanifolds and manifolds fibred in special Lagrangian submanifolds, motivated by the Strominger-Yau-Zaslow conjecture [29]. One of the basic approaches to finding examples is to exploit symmetries of the ambient manifold. If X is a (non-compact) n-dimensional Calabi-Yau manifold with Kähler form ω and nowhere vanishing holo...

A Calabi-Yau threefold is a complex projective threefold X (possibly with some suitable class of singularities, say terminal or canonical) with ω X ∼ = O X and h 1 (O X) = h 2 (O X) = 0. One of the fundamental gaps in the classification of algebraic threefolds is the lack of understanding of Calabi-Yau threefolds. Here I will try to set forth a program to bring the morass of thousands of exampl...

Bernheim (2), studying the properties of the “citric dehydrogenase” system, noted that aconitic acid (presumably the trans isomer) inhibited the reduction of methylene blue by citric acid. More recently, Morrison and Still (3), in a short report, claimed that truns-aconitic acid inhibited competitively the reaction cis-aconitate c citrate, catalyzed by the aconitase of rhubarb leaf. The present...

Cis-diamminedichloroplatinum(II) (cis-DDP) is known as an effective anticancer drug. Its therapeutic effect is supposed to be a consequence of the covalent binding to DNA. A number of cellular proteins were found to bind selectively to DNA modified by cis-DDP (but not by its isomer trans-DDP). Here we present our observations on interaction of the linker histone H1 with cis- and trans-DDP modif...

Reactions of chloroplatinum methyl complexes with N-(arylimino)pyrrolide anions afford cis and trans neutral platinum methyl complexes. Isomers with methyl trans to the pyrrolide nitrogen activate benzene C-H bonds at 85 degrees C more than 80 times faster than the corresponding cis isomer. In addition, reactions of platinum dimethyl complexes with N-(arylimino)pyrroles (Ar = 4-substituted phen...

27-nor-25-Hydroxyvitamin D3, 26,27-bisnor-25-hydroxyvitamin D3, and 22-27-hexanor-20-hydroxyvitamin D3 and the corresponding 5,6-trans isomers have been synthesized. All compounds were tested for their ability to induce intestinal calcium transport and bone calcium mobilization in normal and anephric rats. The 27-nor- and 26,27-bisnor-25-hydroxyvitamin D3 analog are capable of stimulating intes...

Two-photon initiated photo-isomerization of an azobenzene moiety adsorbed on silver nanoparticles (Ag NPs) is demonstrated. The azobenzene is linked to a materials-binding peptide that brings it into intimate contact with the Ag NP surface, producing a dramatic enhancement of its two-photon absorbance. An integrated modeling approach, combining advanced conformational sampling with Quantum Mech...