Montreal has had a longstanding interest in somatostatin. Two years ago when the final planning began for the International Con gress of Endocrinology in Quebec City in July 1984, we seized the op portunity for having a separate Satellite Symposium on somatostatin here in Montreal. We felt that after a decade of uniformly vigorous growth in somatostatin research, the opportune moment had arrived for a review of the most significant past developments and for setting the directions for the future. Knowing the futility of trying to cover every aspect of the burgeoning somatostatin field in a two day scientific program, we opted for a detailed analysis of selected areas which were reasonably mature and of areas of greatest new activity. To attain these objectives, 27 leading international experts actively involved in their fields were invited to present an indepth review of their work in one of five major categories of somatostatin research. Thirty minutes at the end of each session were assigned for a three way, comprehensive discussion of some of the core concepts between the session moderators, the panellists and the audience. The feedback that we have received from the particip ants leaves little doubt that the meeting was a scientific and social success. This book fulfills our final commitment towards the Meeting which was to record the proceedings in a timely publication.

Reproduction is the origination of new organisms from pre-existing ones. Among more than 35 separated forms of reproduction including several types of gamogony, parthenogenesis, agamogenesis, fission and division, and plas motomy, the bisexual mode of reproduction via fertilization provides genetic variability that allows species to adapt quickly to competitive and constantly changing environments. Several excellent reviews and books have been written in the past to analyse the mechanisms of fertilization in different eukaryotic species. During the last few years, however, renewed attention has been paid to examining the process of oocyte fertilization at the cellular/molecular level not only within a single species/group but also through different phylogenetic lineages. As a result of this effort, knowledge of the molecular pathways used by oocytes and spermatozoa at fertilization has increased, but still many ques tions remain to be answered. Being aware of the necessity of providing an inte grated view of the process of fertilization, this book has been entirely devoted to reviewing the process of oocyte fertilization at the cellular/molecular level in two different and separated groups of eukaryotic organisms: protozoa and metazoan animals. The book is organized into six sections dealing with oocyte fertilization in protozoa, invertebrates, teleost fishes, amphibians, birds and mammals. These sections are followed by a summary/concluding chapter that provides a com parative overview of the process of fertilization in these groups of eukaryotes."

The European School of Oncology came into existence to respond to a need for informa tion, education and training in the field of the diagnosis and treatment of cancer. There are two main reasons why such an initiative was considered necessary. Firstly, the teaching of oncology requires a rigorously multidisciplinary approach which is difficult for the Univer sities to put into practice since their system is mainly disciplinary orientated. Secondly, the rate of technological development that impinges on the diagnosis and treatment of cancer has been so rapid that it is not an easy task for medical faculties to adapt their curricula flexibly. With its residential courses for organ pathologies and the seminars on new techniques (laser, monoclonal antibodies, imaging techniques etc.) or on the principal therapeutic controversies (conservative or mutilating surgery, primary or adjuvant chemotherapy, radiotherapy alone or integrated), it is the ambition of the European School of Oncology to fill a cultural and scientific gap and, thereby, create a bridge between the University and Industry and between these two and daily medical practice. One of the more recent initiatives of ESO has been the institution of permanent study groups, also called task forces, where a limited number of leading experts are invited to meet once a year with the aim of defining the state of the art and possibly reaching a consensus on future developments in specific fields of oncology.

1.1 Mechanism of Action of Glucocorticoid Hormones The current model of glucocorticoid hormone action is summarized in Fig. 1. After synthesis, glucocorticoids are secreted into the blood stream and trans- ported to target cells where they bind with high affinity (K-1O-9M) and d specificity to the intracellular glucocorticoid receptor (GR) protein. The sub- cellular localization of hormone-free GR is still a controversial issue. However, most data support the idea that unliganded GR is in the cytoplasmic compartment or loosely associated with the nucleus (Picard and Yamamoto 1987; Gustafsson et al. 1987 and references therein; LaFond et al. 1988; Gasc et al. 1989). Upon ligand binding, GR is activated into a form capable of interacting with DNA. The mechanism of GR activation probably involves a conformational change and dis- sociation from nonreceptor components, e.g., the 90-kDA heat shock protein (hsp90: Pratt et al. 1988; Bresnick et al. 1989; Denis and Gustafsson 1989). The subcellular location of activated GR has been firmly established to be inside the nucleus. In vivo, the hormone-receptor complex interacts with specific DNA Activation r:::.. ~ qc [!3-GC ...&.GC~ j ~ ? , BIOLOGICAL EFFECTS " t , Active Protein , , ~Vl\lent.

This book originates from a symposium held at the London Hospital Medical College under the auspices of Applied Chromatography Systems Ltd. to discuss the place of HPLC in the endocrinology field. Many of the authors of the present book were speakers at this symposium. It seemed to us that many endocrinolo gists did not at that time fully appreciate the value of HPLC, and this book was designed to publicise the potential value of this technique. A survey of methods used in the steroid field Cp 185) confirmed the view that HPLC is not being used as widely, particularly in research described in clinical journals, as might be expected. We hope that this book will illustrate, albeit in a few selected areas of endocrinology, just how versatile and powerful a technique HPLC is, and en courage those who have not yet experienced it to have a go. The beginner does not need to buy expensive instrumentation - all that is required is a pump, injector, column and detector - the rest can come later! All the authors have practical experience in the use of HPLC in the particular area they discuss. All readers who discover apparent errors or who feel that the treatment of a topic of interest can be improved upon are encouraged to contact the editors. All criti cism, especially if constructive, is welcomed. We are still learning, and other peoples' experience is always valuable.

Congenital adrenal hyperplasia (CAH) consists of a group of disorders of adrenal steroidogenesis. Each disorder results from an inherited deficiency of one of the several enzymes necessary for normal steroid synthesis. The different enzyme deficiencies produce characteristic patterns of hormonal abnormalities; the clinical symptoms of the different forms of CAH depend on the particular hormones that are deficient or that are produced in excess. The earliest documented description of CAH was by DeCrecchio in 1865 (DeCrecchio 1865). This Neapolitan anatomist described a cadaver having a penis with first degree hypospadias but no externally palpable gonads. Dis- section revealed a vagina, uterus, fallopian tubes, ovaries, and markedly enlarged adrenals. It is interesting that the subject suffered a confusion of sex assignment, being declared a female at birth and a male 4 years later. He conducted himself as a male sexually and socially. Since the original descrip- tion of this case, investigators have unravelled the pathophysiology of the inborn errors of steroidogenesis. 1 Steroidogenesis and Enzymatic Conversions of Adrenal Steroid Hormones A. Steroidogenesis The adrenal synthesizes three main classes of hormones: mineralocorticoids (17-deoxy pathway), glucocorticoids (17-hydroxy pathway), and sex steroids.

The purpose of these volumes is to provide a reference work for the methods of purifying many of the receptors we know about. This be comes increasingly important as full-length receptors are overexpressed in bacteria or in insect cell systems. A major problem for abundantly expressed proteins will be their purification. In addition to purification protocols, many other details can be found concerning an individual receptor that may not be available in standard texts or monographs. No book of this type is available as a compendium of purification procedures. Receptor Purification provides protocols for the purification of a wide variety of receptors. These include receptors that bind: neurotransmit ters, polypeptide hormones, steroid hormones, and ligands for related members of the steroid supergene family and others, including receptors involved in bacterial motion. The text of this information is substantial, so as to require its publication in two volumes. Consequently, a division was made by grouping receptors by the nature of their ligands. Thus, in Volume One there are contributions on serotonin receptors, adrenergic receptors, the purification of GTP-binding proteins, opioid receptors, neurotensin receptor, luteinizing hormone receptor, human chorionic gonadotropin receptor, follicle stimulating hormone receptor, thyro tropin receptor, prolactin receptor, epidermal growth factor receptor, platelet derived growth factor receptor, colony stimulating factor recep tor, insulin-like growth factor receptors, insulin receptor, fibronectin receptor, interferon receptor, and the cholecystokinin receptor.

'Morphological imaging' and 'functional imaging' are current mainstays for the diagnosis, successful treatment and accurate follow-up of patients with endocrine disorders. Functional and Morphological Imaging of the Endocrine System provides the reader with comprehensive but concise insights in the application of cutting edge imaging techniques and updated imaging protocols for the diagnosis and treatment of hypersecretory hormonal syndromes and functional endocrine masses.

This book includes the most significant contributions of the 3rd International Symposium on MULTIPLE RISK FACTORS IN CARDIOVASCULAR DISEASE held in Florence, Italy, July 6-9, 1994. The meeting focused on the risk factors for cardiovascular disease and their interactions. The need for this symposium is based on the epidemiological evidence that individuals from industrialized countries often possess two or more risk factors which synergistically increase the global risk profile. This has become more evident in recent years with the increase in life expectancy of the general population. The evidence that in high risk patients, a combination of risk factors often is detected, is highlighted in these Proceedings. Many recent epidemiological data identifYing the intrinsic and environmental factors contributing to the development of atherosclerosis are discussed. These results, in parallel with basic and clinical research, underline how atherosclerosis is a complex and multifactorial process involving the influences of lipids, including lipoprotein subfractions, blood pressure, rheologic forces, carbohydrate tolerance, and thrombogenic factors. Furthermore, the risk associated with anyone of these risk factors varies widely depending on level of the associated atherogenic risk factors.

As I reflect on the evolution of this book, I am struck by the differences be tween my early conceptions and the final product. When I was first ap proached by Springer-Verlag regarding a monograph on my interests in the area of fetal lung development, I imagined that it would be relatively easy to summarize my contributions, plus the work of other investigators as needed for proper perspective. This rather naive idea was abandoned as I prepared my initial outlines for the monograph. I quickly realized that con tributions from my laboratory are not sufficient for telling the story of "hormones and lung maturation." The result of this decision is a longer and more heavily-referenced book than I originally envisioned. Although I have attempted to discuss in considerable detail most aspects of hormones and the fetal lung, I know with certainty that I have not in cluded all relevant references in each area. In most of these instances this reflects my impatience or lack of diligence, and I offer my apologies to those investigators whose work has been so omitted. In some situations published work has not been cited in a deliberate decision to limit the breadth of discussion or, rarely, due to my judgment of major shortcom ings in experimental design or execution."

The tridecapeptide neurotensin (NT) was first identified in bovine hypothalamic extracts and characterized by Carraway and Leeman (1973,1975,1976) and has subsequently been found in all classes of vertebrates (Carraway and Leeman 1976; Kitabgi et al. 1976; Kataoka et al. 1979; Langer et al. 1979; Reinecke et al. 1980a; Cooper et al. 1981; Grant et al. 1982; Carraway et al. 1982; Eldred and Karten 1983), many invertebrates (Reinecke et al. 1980 b; Grimmelikhuijzen et al. 1981; Price et al. 1982), and certain bacteria (Bhatnagar and Carraway 1981). It is distributed throughout the mammalian central nervous system (CNS) (Uhl and Snyder 1977 a, b), gastrointestinal tract (Sundler et al. 1977; Schultzberg et al. 1980), cerebrospinal fluid (CSF), adrenals, pancreas, and plasma (Fernstrom et al. 1980). When administered systemically, the peptide has a variety of effects such as hypotension, hyperglycemia, decreased gastric acid secretion, decreased gut motility, and altered secretion of anterior pituitary hormones (Leeman and Carraway 1982). NT apparently does not cross the blood-brain barrier in appre- ciable quantities; however, when administered directly into the CNS, it produces a number of physiological and behavioral effects. A burgeoning body of evidence supports the role of NT as a neurotransmitter or neuromodulator. Thus far, het- erogeneous CNS distribution, release of NT upon neuronal depolarization, satu- rable and specific binding of NT to receptors, and degradation by peptidases have all been demonstrated.

Upon wresting the control of the earth from the Titans, Zeus assigned the task of creating living creatures to two Titan brothers who had sided with him in the epic battle just concluded. Because Epimetheus, who had been endowed only with hindsight, had the first hand in this creation, all the good attributes were exhaus ted by the time the lion, the elephant and other animals were created. When the time came for the creation of man, there were precious few materials left to work with. Not surprisingly, man was made weak and naked. Prometheus took pity on this miscreation and gave man the use of fire. For this foresight, Zeus meted out horrible punishment, binding Prometheus to a rocky pillar in the Caucasas Moun tains and letting a vulture consume his liver daily. It seems to me that the ancient Greeks in their unfathomable wisdom under stood the essence of the evolutionary process very well. Had Escherichia coli of 200 million years or so ago been endowed with the foresight to anticipate the eventual emergence of and subsequent dominance by mammals of this Earth, they would no doubt have equipped themselves, in anticipation of the coming cer tainty, with the lac operon to deal with lactose in the suckling mammalian infant's gut. Had they been able to do so, the actual emergance of mammals would have exerted no selective pressure upon existing E. COLI."

It is a truism that as we age there are a number of underlying physiological changes conspiring to alter our level of behavioral and cognitive function ing. Despite the inherent interrelatedness of these behavioral and cognitive changes, all too often the papers we read confine themselves to specific, isolated components of the developing process. Although exceptions nat urally exist, we believe that these exceptions should become rule. Although an integrated approach is important in all areas of adult devel opment, it is perhaps particularly germane in the study of atypical aging. Here, changes in overall functioning can occur in rapid succession, with the synchrony of decline between different subprocesses making it difficult to factor changes in one process from changes in another. For example, because changes in cognitive functioning co-occur with other dramatic changes in (motoric) response capacities, it is unclear how one can effec tively study changes in the ability to cognize independent of changes in the very mechanisms (ability to execute motor sequences) so often used to index cognitive performance."

Endocrinologic investigations during pregnancy have focused in the last decades on placental hormones, the maternal endocrine system and maternal fetal interactions. Less is known about the fetus itself and the interaction of fetal hormonal response and physiological parameters. In this book physiologists, pediatricians and obstetricians active in experimental studies in both physiology and endocrinology combine both aspects of investigations. Historical remarks on the endocrine development of the fetus are followed by observations of the hormonal control of the cardiovascular system. Basic mechanisms of fetal endocrine control such as brain development, fetal growth, fetal behaviour, and thermoregulation are given particular consideration. Finally, carbohydrate metabolism and the mechanism of parturition are outlined.

It has been my privilege and pleasure during the past half century to participate in the unfolding of present-day concepts of the mammalian female reproductive cycles. When the studies recorded here began in the late 1930s it was already established that cyclic ovarian function is governed by gonadotropic secretions from the anterior pituitary gland, the "conductor of the endrocrine orchestra," and that in turn this activity is importantly dependent in some way upon secretion of estro gens and progesterone by the ovaries. Although a role of the nervous system was recognized for the reflex-like induction of ovulation in rabbits and cats and the in duction of pseudopregnancy in rats and mice, and although there was even some evidence of neural participation in ovulation in rats, a major central neural role in the female cycle of most species was not apparent. Gonadotropic fractions of pitui tary extracts having distinct follicle-stimulating and luteinizing activities in test ani mals had been obtained, and these respective effects had been fairly well charac terized. Prolactin was well known for its lactogenic activity, but its luteotropic role in rats and mice had yet to be revealed. The molecular structure of the several estro gens and progesterone was known, and they were readily available as synthetic pro ducts. The broad concept of ovarian-pituitary reciprocity appeared to be an accept able explanation of the female cycle, with the ovary in control through the rhythmic rise and fall in secretion of follicular estrogen.

It is fourteen years since insulin was last reviewed in The Handbook of Ex perimental Pharmacology, in volume 32. The present endeavor is more modest in scope. Volume 32 appeared in two separate parts, each having its own subeditors, and together the two parts covered nearly all areas of insulin pharmacology. Such comprehensiveness seemed impractical in a new volume. The amount of in formation related to insulin that is now available simply would not fit in a reasonable amount of space. Furthermore, for better or worse, scientists have be come so specialized that a volume providing such broad coverage seemed likely in its totality to be of interest or value to very few individuals. We therefore decided to limit the present volume to the following areas: insulin chemistry and structure, insulin biosynthesis and secretion, insulin receptor, and insulin action at the cellular level. We felt these areas formed a coherent unit. We also felt, perhaps as much because of our own interests and perspectives as any objective reality, that these were the areas in which recent progress has been most dramatic, and yet, paradoxically and tantalizingly, these were the areas in which most has yet to be learned. Even with this limited scope, there are some major gaps in coverage. Regrettably, two important areas, the beta cell ATP-sensitive potassium channel and the glucose transporter, were among these. Nevertheless, the authors who con tributed have done an excellent job, and we would like to thank them for their diligence.

Research in diabetes has accelerated in two areas, both of which are being reviewed in CTMI. The first is the use of a variety of animal models; the second is basic research in human investigation, islet cell antigens, and mapping of genes as sociated with susceptibility to disease. Dr. Thomas Dyrberg accepted editorial responsibility for this volume, which covers the first area. A second book, to be published later in the year, is edited by Drs. Brekkeskov and Hansen (CTMI 164, see page VI for contents). Although the contributors to both volumes represent the international scientific community, the editors are from the Hagedorn Research Laboratory in Denmark. Work at this institute and the Steno Memorial Hospital has been dedicated to research in diabetes for decades, and the insti tutions were appointed WHO Collaborating Centres for Re search and Training on the Pathogenesis of Diabetes Mellitus in 1983. It is worth noting that while addressing the hypothesis of the role of class II major histocompatibility glycoproteins in autoimmune diabetes (insulin-dependent diabetes, IDDM) a number of investigators established animal models in which class II molecules were expressed under the control of the rat insulin promoter. While generating interesting information on 100M, the finding of immunologic tolerance in such transgenic mice has attracted the attention of several basic immunologic laboratories for quite different reasons. Thus, we are reminded again of the Pasteur dictum that "chance favors the prepared mind. " Michael B. A. Oldstone, M. D."

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."

The account of "neonatal sterilization" is the story of the advocates of direct effect of steroids on the gonads and those who believed in the indirect influence, mediated through the hypothalamus and/or the pituitary gland. As often happens in biology, both convictions represent the same image seen from different perspectives. Prof DC Johnson (Kansas City, KS) reminisced the beginning of the story in a letter to me. I am paraphrasing parts of the letter with his permission. "As a starting point we could pick the life-long research of Emil Steinach ... " Steinach recognized the influence of testes on the develop ment of accessory sex organs in 1894, described virilization of females and feminization of males in 1913, and identified the controlling influence of the hypophysis on the gonads in 1928. He reviewed his work in a book Sex and Life, Forty Years of Biological and Medical Experience (E Steinach and L Loebe!; Faber and Faber, London, 1940). He got on the wrong road in later years and that is the reason everybody seems to have forgotten him. He presented his hypothesis that estrogen has a direct effect upon the testes, i. e. hormone antagonism, at the 1st International Congress on Sex Research in 1926.

This monograph represents the first comprehensive review of hormones in human amniotic fluid and includes data published up to and including 1980. Recently, more extensive use of amniocentesis for prenatal diagnosis and evaluation of fetal lung maturation has shown that amniotic fluid hormone measurements can aid in the diagnosis of fetal and placental abnormalities. The material is presented in two main sections dealing with steroid and protein hormones. The methods of identification and quantitation are delineated, and the findings are discussed in relation to the clinical conditions. In addition, particular attention has been directed towards up-to-date review of the sources, metabolism and transfer of human amniotic fluid hormones. The review is intended to serve the needs of clinicians, basic scientists and students, providing detailed information on human amniotic fluid hormones in order to improve patient care and indicate possibilities for further investigations. Ttibingen, January 1982 A.E. Schindler Contents Introduction A. 1 Origin of Human Amniotic Fluid . 2 B. C. Origin and Regulation of Steroids in Human Amniotic Fluid . 5 D. Methods of Isolation and Identification of Steroids in Human Amniotic Fluid 6 I. C , C , and C Steroids . 6 30 29 28 II. C Steroids 6 27 1. Cholesterol 6 2. Cholestanol . 6 3. ,::l7 -Cholestenol and ,::l8 -Cholestenol. 6 4. 7-Dehydrocholesterol and Desmosterol . 6 ,::l5_C Steroids. III. 7 21 1. Pregnenolone 7 2. 16cx-H ydroxypregnenolone. 7 3. 17cx-Hydroxypregnenolone.

Dr. Raymond Pederson, Dr. Jill Dryburgh and I commenced work on GIP in 1968, when, with the generous help of Professor Viktor Mutt and Professor Erik Jorpes of the Karolinska Inst, itute, Stockholm, we were able to establish that there existed an inhibitory material for acid secretion in cholecystokinin-pancreozymin prepara tions. Once the physiological evidence for the inhibitor was established it seemed appropriate to seek help in its isolation. Dr. J. Dryburgh and Dr. R. Pederson were left to bioassay fractions in Vancouver whilst I enjoyed the company of Professor Mutt at the Karolinska for one year, as a Medical Research Council of Canada Visiting Scientist. Purification of the inhibitory factor proceeded rapidly due, in no small measure, to Professor Mutt's untirmg efforts on my behalf. Later that year, Dr. Dryburgh joined us in Stockholm to begin the sequence work on GIP. This was completed late in 1970 in Vancouver. In Stockholm in June 1970, I met a fellow Canadian Dr. John Dupre (McGill University) at a cocktail party who kept commenting about the possibility of GIP being an insulinotropic hormone, the "incretin" of earlier days. At that time, gastrointestinal physiologist as I was, I did not recognize the importance of his comment. This became apparent two or three years later when Dr. Dupre demonstrated that GIP was insulinotropic in man. In 1972, Maryanne Kuzio and Dr."

The term polycystic ovary syndrome (peOS) is meant to describe a clinical endocrinopathy characterized by menstrual irregularity and evidence of hyperandrogenism. While recognized since the 1800s, a clinical composite was not constructed until 1935 when Stein and Leventhal reported their findings of seven women with infertility, menstrual dysfunction, hirsutism, and enlarged ovaries. Notably, the ovaries contained numerous multiple cysts and the ovarian capsule was thickened. At the time, this preciseness of definition was sufficient to entitle the entity Stein-Leventhal syndrome. Subsequently, over the intervening years as investigators attempted to un ravel the pathophysiology and genesis of this disorder and the number of reported studies increased, there ensued a gradual and distinct terminologic conversion to polycystic ovary syndrome, which, whether intentional or not, connoted a less well-defined condition. Perhaps this is appropriately so, given the seemingly broadening spectrum of clinical presentations and the continuing debate over what constitutes peos. The expansive new knowledge about peos was discussed to a significant degree at an international symposium organized by Serono Symposia USA and held in Boston in the late spring of 1995. Ovarian physiology, including the fate of the follicular unit, was a central focus with several presentations on the genesis, growth, and death of ovarian cellular components. A discus sion of the regulation of ovarian cell function was also highlighted and comprised a major portion of the program."

A large number of chemical agents are known which affect blood and blood-forming organs. The purpose of this volume is to review the sig- nificant advances made over the past several years regarding such chemical agents. The purification, biological action, and therapeutic implications of several widely used hematopoietic growth factors such as interleukin 3 (IL-3 or multi-CSF), granulocyte/macrophage colony stimulating factor (GM-CSF), granulocyte colony stimulating factor (G-CSF), colony stimu- lating factor (CSF-I or M-CSF), thrombopoietin, and erythropoietin are included in this volume. These factors are important in regulating several hematopoietic cell lines such as neutrophils, monocytes, eosinophils, macrophages, megakaryocytes, platelets, and erythrocytes. People are exposed daily to numerous toxic chemical substances present in our environment which produce a suppression of erythropoiesis, myelo- poiesis, lymphocytopoiesis, and megakaryocytopoiesis. Attempts have been made in this volume to assess the therapeutic role of some of the hematopoietic factors such as erythropoietin in the anemia of end stage renal disease, as well as colony stimulating factors in other hematopoietic abnormalities. In addition, some of the chemical factors in our environment which suppress major hematopoietic lineages stimulated by erythropoietin, macrophage colony stimulating factor, granulocyte colony stimulating factor, interleukin I-alpha, interleukin I-beta, and interleukins 2, 3, 4, 5, 6, 7, and 9 are also included. An updating of the mechanism of action of each of these factors on the major hematopoietic lineages is covered.

The eleventh monograph and meeting of the Foundation on "Hormon al Control of the Hypothalamo-Pituitary-Gonadal Axis" was held in October 1983 at the Weizmann Institute of Science. This monograph honors the memory of Professor Hans R. Lindner, a productive and innovative scientist greatly respected and admired by his col leagues. When addressing the opening session I remarked that my impres sion of the Weizmann Institute was one or two large buildings hous ing the various departments. This was my first visit to Israel and I was overwhelmed by the beautiful semi-tropical gardens of the in stitute, in a setting of shrubs and trees, orange groves and flow ers. Sited among this seventy-five acres are over fifty buildings and residential areas for the staff and visiting scientists. I saw pictures of this area when Dr. Chaim Weizmann founded in 1934, the Daniel Sieff Research Institute, the forerunner of the Weizmann In stitute. The site was sand dunes without a blade of grass. That the desert shall bloom is illustrative of the progress made in Is rael. The topics of the monograph are grouped into twelve sections.

The field of human artificial reproductive technology (ART) is continually advancing and has witnessed significant changes since the inception of Louise Brown in 1978. Though Louise Brown herself was conceived after the trans fer of a blastocyst, there remain significant confusion and debate regarding the stage at which the human embryo conceived in the laboratory should be replaced in the mother. Developments in culture media formulations, leading to the introduction of sequential media, have brought the role of the blasto cyst in human ART back into the spotlight. It was due to this resurgence of interest in the niche of extended culture in human infertility treatment that the symposium on "ART and the Human Blastocyst" was held. of this meeting within this volume bring to the forefront The proceedings the main issues raised with the transfer of embryos at the blastocyst stage. It is evident from the chapters that follow that ART needs to be perceived as a continuum of procedures, each one dependent on the preceding one, and all equally as important as each other. That is to say, the development of a com petent embryo is ultimately dependent on the quality of the gametes from which it was derived. With regard to the oocyte, this then places the emphasis on the physician to use a stimulation protocol that both produces quality oocytes and does not impair endometrial function. Maintenance of gamete and embryo quality is the laboratory's role.