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Edited by Richard P. McBrien. San Francisco, Calif.: HarperSanFrancisco, 1995. 1349 pp. $45.00. In the introduction to this book, McBrien writes, "The purpose of this encyclopedia is to provide a [...]

Purpose: Magnetic resonance imaging (MRI)‐based investigations into radiotherapy (RT)‐induced cardiotoxicity require reliable registrations of magnetic resonance (MR) imaging to planning computed tomography (CT) for correlation to regional dose. In this study, the accuracy of intra‐ and inter‐modality deformable image registration (DIR) of longitudinal four‐dimensional CT (4D‐CT) and MR images were evaluated for heart, left ventricle (LV), and thoracic aorta (TA). Methods and materials: Non‐cardiac‐gated 4D‐CT and T1 volumetric interpolated breath‐hold examination (T1‐VIBE) MRI datasets from five lung cancer patients were obtained at two breathing phases (inspiration/expiration) and two time points (before treatment and 5 weeks after initiating RT). Heart, LV, and TA were manually contoured. Each organ underwent three intramodal DIRs ((A) CT modality over time, (B) MR modality over time, and (C) MR contrast effect at the same time) and two intermodal DIRs ((D) CT/MR multimodality at same time and (E) CT/MR multimodality over time). Hausdorff distance (HD), mean distance to agreement (MDA), and Dice were evaluated and assessed for compliance with American Association of Physicists in Medicine (AAPM) Task Group (TG)‐132 recommendations. Results: Mean values of HD, MDA, and Dice under all registration scenarios for each region of interest ranged between 8.7 and 16.8 mm, 1.0 and 2.6 mm, and 0.85 and 0.95, respectively, and were within the TG‐132 recommended range (MDA < 3 mm, Dice > 0.8). Intramodal DIR showed slightly better results compared to intermodal DIR. Heart and TA demonstrated higher registration accuracy compared to LV for all scenarios except for HD and Dice values in Group A. Significant differences for each metric and tissue of interest were noted between Groups B and D and between Groups B and E. MDA and Dice significantly differed between LV and heart in all registrations except for MDA in Group E. Conclusions: DIR of the heart, LV, and TA between non‐cardiac‐gated longitudinal 4D‐CT and MRI across two modalities, breathing phases, and pre/post‐contrast is acceptably accurate per AAPM TG‐132 guidelines. This study paves the way for future evaluation of RT‐induced cardiotoxicity and its related factors using multimodality DIR. [ABSTRACT FROM AUTHOR]

A general scheme for the transformation of ribonucleosides into the corresponding sugar-modified derivatives is presented. Mixtures of 2'-3'-bromohydrin acetates with different O5' substituents were formed from the reaction of purine, pyrimidine and mofidied purine ribonucleosides with 2-acetoxy-2-methylpropanoyl (alpha-acetoxyisobutyryl)bromide in acetonitrile. Reductive elimination with zinc-copper couple or zinc powder in the presence of acetic acid affords the formation of unsaturated-sugar nucleosides.

Describes production of the Bayou State Periodical Index, an index of Louisiana periodicals designed to provide access to information on local topics, and offers guidelines for producing such an index in a timely fashion with limited funds, using a microcomputer. Planning, procedures, financing, and publicity and marketing are covered. (seven references) (MES)