Influence of cisplatin intrastrand crosslinking on the conformation, thermal stability, and energetics of a 20-mer DNA duplex.

cis-Diamminedichloroplatinum(II) (cisplatin) is a widely used anticancer drug that binds to and crosslinks DNA. The major DNA adduct of the drug results from coordination of two adjacent guanine bases to platinum to form the intrastrand crosslink cis-[Pt(NH3)2[d(GpG)-N7(1), -N7(2)]] (cis-Pt-GG). In the present study, spectroscopic and calorimetric techniques were employed to characterize the influence of this crosslink on the conformation, thermal stability, and energetics of a site-specifically platinated 20-mer DNA duplex. CD spectroscopic and thermal denaturation data revealed that the crosslink alters the structure of the host duplex, consistent with a shift from a B-like to an A-like conformation; lowers its thermal stability by approximately 9 degrees C; and reduces its thermodynamic stability by 6.3 kcal/mol at 25 degrees C, most of which is enthalpic in origin; but it does not alter the two-state melting behavior exhibited by the parent, unmodified duplex, despite the significant crosslink-induced changes noted above. The energetic consequences of the cis-Pt-GG crosslink are discussed in relation to the structural perturbations it induces in DNA and to how these crosslink-induced perturbations might modulate protein binding.

Estudios literarios.

Francisco Acuña de Figueroa.--Diógenes y sus ideas.--Los poetas de la revolución.--La religion y la ciencia. (Juicio critico sobre el libro de Draper)--César Diaz.--Juna Cárlos Gomez.--Cuadros de costumbres: El gaucho. Un gobierno de otros tiempos. Las trillas.

The powder metallurgy of uranium /

Uranium is a ductile metal and cannot be comminuted to a fine powder by any mechanical means such as crushing, milling or grinding. Uranium, however, reacts readily with hydrogen and forms UH3, which is a fine powder of less than 400 mesh screen size. The factors controlling the rats of the hydride formation are: (a) The surface area of the metal; (b) the temperature at which the reaction takes place; (c) the pressure of hydrogen. In order to increase the reaction area, one has to hydride small metal pieces rather than a single mass. The hydrogen reacts with uranium metal at temperatures as low as 100 deg to 1500 deg, and the reaction rate becomes quite rapid at approximately 225 deg C. The hydrogen for this purpose has to be of high purity and any small amount of oxygen in hydrogen delays the start of the reaction.

Plutarch's life of Themistokles /

Greek text with English introd. and commentary.

Der Sensualismus des Demokritus und seiner Vorgèanger mit Bezug auf verwandte Erscheinungen der neuern Philosophie / Johnson.

Programm--Gymnasium u. Realschule zu Plauen i.V.

Über ein Bildnis des Perikles in den Königlichen Museen /

Includes bibliographical references.

Greek writers of Roman history : some reflections upon the authorities used by Plutarch and Appianus /

The fons primarius of Plutarch's life of Fabius Maximus. -- The common Greek sources of Plutarch and Appianus for Roman history. -- King Juba's Historia romana.

Monita et eiusdem morientis extremae voces, ex codicibus Parisinis saeculi VII et IX,

According to E. Woefflin this collection of spothegms derived from Seneca and other sources, with an epilogue "Sententiae Rufi", and entitled by him "Monita", was composed by Seneca shortly before his death, and the "Sententiae Rufi" were the last words uttered by him.

The speeches of Isaeus,

Notes: p. [175]-723.

Petronii Saturae et Liber Priapeorum.

Includes indexes.

Life of Timoleon,

First ed. published in 1889.

Philodem von der Musik : ein Auszug aus dessen viertem Buche /

Includes bibliographical references.

Essai sur la poésie philosophique en Grèce : Xénophane, Parménide, Empédocle /

Includes bibliographical references.

Lykourgou Logos kata Leōkratous /

Edited by Adamantios Koraēs, translated by François Thurot.