Frontiers In Thyroidology

"Frontiers In Thyroidology" assembles the prize lectures, symposia, and papers presented during the Ninth International Thyroid Congress in Sao Paulo, Brazil in September, 1985. This book represents the State-of the-Art in thyroid studies with its continuous expansion into the areas of immunology, molecular biology, clinical and environmental medicine. As its name also indicates, the material compiled in this volume defines important questions to be answered in basic and applied aspects of the thyroid. So, this book clearly demonstrates the rewards, excitement, and challenges posed by the thyroid gland. Once again, the thyroid gland, through its unique and important functions and implications in health and disease, has been able to congregate scientists throughout the world to communicate their findings, to share their expertise and experiences, and to strengthen their bonds of friendship and commitment to make a better world through their work. This publication consists of 309 papers in 19 different topics. The prize lectures and symposia review and update our knowledge in basic and clinical aspects of exceptional interest in the thyroid field. "Frontiers in Thyroidology" adds to a series of publications from previous interna tional thyroid meetings which includes: "Advances in Thyroid Research", London, 1960; "Current Topics in Thyroid Research", Rome, 1965; "Further Advances in Thyroid Research", Vienna, 1970; "Thyroid Research", Boston, 1975, and "Thyroid Research VIII", Sydney, 1980. We would like to express our gratitude to Mrs. P. Langford and Drs.

The discovery of the negative feedback of thyroid hormones on pituitary thyroid-stimulating hormone (TSH) secretion, a classical endocrine feedback control system, has shaped diagnosis and treatment of thyroid disease for the last decades. Based on this concept, a unique diagnostic category of subclinical thyroid disorders was introduced, being defined exclusively by an abnormal TSH response in the presence of thyroid hormone concentrations within the reference range. Although this approach was able to deliver a conceptually straightforward disease definition problems surfaced in clinical practice as neither the diagnostic reference range nor the appropriate threshold for initiating substitution treatment are universally agreed upon for subclinical thyroid disorders. The situation is further aggravated by the so-called syndrome T, which comprises a substantial but heterogeneous group of L-T4 treated patients with hypothyroidism with reduced quality of life despite “normal” TSH values. A limited understanding of the physiological relationships between TSH and thyroid hormones may be a main reason for clinical difficulties in dealing with the causes of syndrome T and tailoring substitution therapy for hypothyroid patients with subclinical thyroid disorders. Feedback regulation has recently been shown to be much more complex than previously assumed. The concept of homeostatic control has also been extended to include the lesser known but equally important allostatic thyroid regulation.The latter aims at adaptive homeostasis or stability through changing setpoints and modulating structural parameters of feedback control, as may be appropriate to adapt to a vast array of conditions spanning from fetal life, aging, pregnancy, exercise, starvation, obesity, psychiatric disorders to the severe non-thyroidal illness syndrome. A better understanding of homeostatic and allostatic mechanisms, which govern the behaviour of pituitary-thyroid feedback control, is on the horizon. This promises to improve the diagnostic utility of laboratory methods, laying the foundation for personalised methods to optimise dosage and modality of substitution therapy. The emerging new world of thyroid physiology is reflected on the side of clinical medicine in a new, relational paradigm for diagnosis and treatment. Considerable progress has been made in this respect in the following key areas: • the significance of complementary information processing structures within the feedback loop, in particular ultrashort feedback of TSH on its own secretion and the action of a TSH-T3 shunt unburdening the thyroid from T4 synthesis in imminent thyroid failure, • the unravelling of spatio-temporal dynamics of hormone concentrations ranging from ultradian to circannual rhythms and including hysteresis effects, • the emergence of “non-canonical” mechanisms of thyroid hormone signalling beyond transcriptional control of gene expression, • the physiological actions of thyronine metabolites, which have been previously regarded as biologically inactive, such as thyronamines and iodothyroacetates, • the characterisation of distinct patterns in the adaptive processes to stress and strain and their conclusive explanation through reactions to type 1 and type 2 allostatic load. This collective volume contains the contributions to the Research Topic “Homeostasis and Allostasis of Thyroid Function”, which was originally published by the journal Frontiers in Endocrinology. Authored by an international team of experts from three continents ,the book provides a comprehensive overview on thyroid control from recent research in basic, computational and clinical thyroidology. Many aspects addressed here can be expected to stimulate future research. A more comprehensive view and better integration of in-vitro, in-silico and in-vivo investigations will be invaluable in paving the way to this new world of thyroidology.

In 1956, three groups independently reported evidence that some thyroid disease appearing spontaneously in humans or experimentally induced in animals are related to autoimmune processes. The interval between these landmark discoveries and the present has witnessed a remarkable and continuing growth of both knowledge and concepts concerning the mechanisms of immune regulation, the pathogenesis of autoimmune thyroid diseases, and their clinical and laboratory manifestations. More importantly knowledge of thyroid autoimmunity has, in many respects, comprised the vanguard of an ever increasing appreciation and understanding of autoimmune diseases in general. On November 24-26 1986, an International Symposium on Thyroid Autoimmunity was held in Pisa. Its purpose was to commemorate the birth of thyroid autoimmunity as a scientific discipline, to summarize current knowledge and concepts in this area, and where possible, to anticipate areas of opportunity for the future - hence the theme of the Symposium, Memories and Perspectives. To open the meeting, the Magnifico Rettore (Chancellor) of the University of Pisa granted special Awards to Dr. Deborah Doniach, Dr. Ivan Roitt, and Dr. Noel R. Rose, who published the first fundamental studies in the field of thyroid autoimmunity, and to Dr. Duncan G. Adams, whose discovery of the long-acting thyroid stimulator (LATS) opened the door to our current understanding of the pathogenesis of Graves' disease. During the meeting thirty plenary lectures were presented.

First multi-year cumulation covers six years: 1965-70.

Current knowledge relevant to the understanding of thyroid autoimmunity is summarized in this book. Some of the world's leading scientists in this field review recent data from four subject areas: immunogenetics, thyroid peroxidase as an antigen, environmental factors, and cytokines. Much ongoing and as yet unpublished work is described, especially in the discussion included after each article. This information is of particular interest since the body of knowledge in these fields is growing very rapidly. The book is based on a workshop in which researchers from 13 countries took part. One major aim was to raise controversial points and to develop ideas for their potential solution. At the workshop it became apparent that a great deal of the information given in textbooks is outdated. This is an important update for researchers who are interested in the above topics and in understanding the etiology and pathogenesis of thyroid autoimmunity.

Imaging studies are playing an increasingly role in the evaluation of endocrine diseases; accordingly, familiarity with the specific indications for the various modalities, and with the characteristic findings, is essential. This well-illustrated volume is intended for both radiologists and endocrinologists, and considers in detail the role of all the most recent imaging techniques within this field.