Endocrinology and Metabolism: Progress in Research and Clinical Prac tice is a new series that has been designed to present timely, critical reviews of constantly evolving fields; to provide practical and up-to-date guidance in the solution of pertinent clinical problems; to offer an alterna tive to the laborious search of the literature (and the often frustrating reading of highly technical articles); and to translate the language of the laboratory into that of the practice of medicine. We think that this volume and those to come will prove useful to physi cians (and to physicians in training), as well as to investigators in a wide variety of specialties; in short, to anyone who seeks answers to questions in endocrinology and metabolism. The first chapter of this volume could well serve as a general introduc tion to the entire series. It points out how our growing understanding of the molecular basis of biologic communication has led to the discovery of a growing number of clinical syndromes, as well as to the realization that phenotypically similar diseases may have radically different pathogenetic mechanisms and thus may require radically different therapeutic strata gems."

Experts in the field of endocrinology as well as ophthalmologists, oncologists, orthopedists and oral surgeons discuss the nature and mechanism of action of growth-stimulating substances whose biological and clinical activities in humans have been demonstrated or are being investigated. The monograph represents a good sampler of current basic and applied knowledge in the field.

Omnis cellula e cellula, "every cell from a cell," was dogma to the 19th century cellular physiologist and the cornerstone of Virchow's Cellular pathologie. "Spread out a cell into a layer and you will find that, in ceasing to be a cell, it has ceased to act as such," wrote the British 1 physiologist G . R. Lewes more than a century age. "The cell remains vital as long as its wall remains intact . . . " keeping its content "pure and clear" and thus preserving the "vital principle" within, echoed Claude 2 Bernard a few years later. The notion of the cell membrane as a pro tecting envelope held sway until it became clear that it could not account for the "coalescence" of poorly differentiated embryonic "vesicles" and for their transformation into "cell-like structures" capable of auto regulation and yet subject to what the grandfather of one of us defined as the "federal obligations imposed by the whole organism., 3 A new concept was needed, and soon the membrane was described as a structure capable of uniting as well as separating adjacent cells. Morphologic evidence for this dual function was obtained several years later when the electron microscope revealed the existence of tight and gap junc tions which, acting as intercellular bonds and channels, allowed the cells to communicate with one another and thus coordinate their biologic activities."

In the middle of the 17th century, the great French philosopher Rene Descartes wrote (L'Homme, J. Le Gras, Paris, 1669) that a suitable stimulation of the brain results in two types of "movements": exterior movements, designed to seek desirable ends and to avoid undesirable or harmful ones and interior movements or "passions" which through the release of "animal spirits" regulate the heart, the liver, and other organs. When it appears appropriate to meet a threat with force, the passion of rage causes the release of strong spirits, whereas when avoidance appears to be the better choice, the passion of fear causes the brain to release weak spirits. We do not know what influence, if any, Descartes had on the thinking of Walter B. Cannon (Bodily Changes in Pain, Hunger, Fear and Rage, Appleton and Co. , New York, 1920), of Hans Selye (The Story of the Adaptation Syndrome, Acta, Inc. , Montreal, 1952), ofG. W. Harris or of R. Guillemin (Hypothalamic-Hypophysial Interrelationships. A Sym posium. c. c. Thomas, Springfield, 1956), but it is interesting to reflect upon the durable value of great ideas which constantly resurface even if modified by other ideas and by new techniques, as if propelled by a preordained intellectual imperative.