E. James Potchen

Effect of irradiation on tumor microvascular permeability to macromolecules

In C3H mouse Gardner lymphosarcoma, we have demonstrated an increase in the extravascular albumin space 48 hours after delivering 3,000 rads of irradiation. This observation has implications for organ radiobiology in that the microvascular effect could alter radiation response in tumors. This effect may be time dependent and thus may be an extremely important consideration in dose fractionation which is not necessarily dependent on tumor cell cytokinetics. The second ramification of this observation concerns the effect of irradiation on radiotracer techniques designed to identify tumors; following irradiation, an increased macromolecular transport into the interstitial space of a tumor would be anticipated to cause increased accumulation of scanning agents which are bound to protein (e.g., gallium).

The physiologic factors affecting regional ventilation and perfusion.

Nuclear medicine laboratories are currently evaluating regional physiology by the use of lung perfusion and ventilation scans. The standard lung perfusion scan has an important and accepted position in the clinical detection of pulmonary emboli. Ventilation quantitation by several techniques are under investigation in many laboratories. We have surveyed some recent developments in our understanding of pulmonary physiology and anatomy and their influence on the distribution of air and blood to various portions of the lung. The interrelation of ventilation and perfusion as well as factors (for example, the effect of gravity) affecting both ventilation and perfusion are emphasized. The effect of respiratory volume (physiologic) and airway obstruction (pathologic) and their influence on the various tracer methods evaluating regional ventilation are discussed. Our current understanding of microvascular anatomy, broncho-pulmonary collateral circulation, and the effect of alveolar hypoxia is related to the evaluation of regional pulmonary perfusion.

Dexamethasone therapy of triethyltin induced cerebral edema

Abstract After administration of 1.25 mg/kg triethyltin bromide daily to rats for 7 days, cerebral edema results characterized by increased brain water and sodium, normal brain potassium, decreased cerebral blood volume, and without evidence for increased microvascular permeability to albumin and pertechnetate. Concurrent administration of dexamethasone diminishes mortality and the severity of brain edema and also significantly decreases brain, liver, and blood levels of triethyltin. It seems likely that the beneficial effect of steroid therapy in this model is at least in part due to enhanced excretion or catabolism of triethyltin bromide.

Biology and the Future of Man

What is basic science? How does it relate to modern medicine? More important, how can priorities in scientific endeavor affect the future of man? In an effort to answer these questions, the National Academy of Science, through its Committee on Science and Public Policy, undertook a massive statement-ofthe-arts survey which is condensed in this book. Dr. Handler, the current Academy president, edited contributions from 175 of the most illustrious names in American bioscience. Although the book is remarkably comprehensive, the interests of the chosen experts are apparent through the omission of other material that equally competent experts would have considered important. Some aspects of basic science are covered in too great a depth to be comprehended by those unfamiliar with the field, whereas others are covered too superficially to provide useful material. The overall quality of the presentation is superb and, as best I can judge, the material is accurate.

Selective Arteriography of the Spinal Cord

This authoritative monograph represents the definitive treatise on a narrow subject, one which will interest physicians dealing with spinal cord disease. The authors have developed clinical techniques to identify the spinal cord vessels. The book emphasizes myelography and selective angiography, while at the same time recognizing the limitations of aortography. The authors clearly define the anatomy and physiology of the spinal cord supply and then show the clinical utility of radiologic methods to evaluate spinal cord symptoms. This leads to discussion of the clinical evaluation of arterial venous malformation and spinal cord tumors, lesions in which these techniques will be most helpful. They discuss possible complications, and in so doing clarify previous misunderstandings and alert the reader to optimal technique necessary to limit the risks of this diagnostic modality. The book is well written and although of limited scope will prove a valuable addition to the library of the neuroradiologists,

Clinical Scintillation Scanning

ABSTRACT The rapid growth of nuclear medicine is largely due to our ability to map out the anatomic deposition of radionuclides. These scintiscanning techniques are uniquely useful in assessing some alterations in regional physiology. Although many recent books contain similar material, Clinical Scintillation Scanning is the most comprehensive text devoted entirely to this subject.An introductory chapter, well written by Dr. Benidict Cassen, who originated scintiscanning, places the field in historic perspective. Subsequent chapters discuss radiopharmaceuticals, instruments, organ-imaging techniques, and their clinical applications. Each major scanning technique is presented in a systematic manner. The chapter on radiopharmaceuticals is an outstanding contribution and ranks with the best written on that subject. Although clearly written, the chapter on instruments is too esoteric to be appreciated by the physician for whom it was intended. The appendix contains radiopharmaceutical tables which bring together information previously found only in scattered sources.The book has a major