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This book covers biologically produced toxins, their chemistry, mode of action, and potential therapeutic applications. In the first part of the book, readers are introduced to the fundamental chemistry of biotoxins, their mechanisms of action, and possible antidotes, paving the way for a deeper understanding of their therapeutic potential. Subsequent chapters outline different types of biotoxins and their impact on food quality and safety, and their potential applications in agriculture and medicine. Particular attention is given to terrestrial and aquatic phytotoxins, bioactive metabolites produced by microorganisms and plants, mycotoxins, phycotoxins, cyanotoxins, neurotoxins of natural origin, bacterial toxins, insect toxins and marine toxins. An authoritative perspective on topics like bioterrorism and the military potential of biological toxins is also offered in this book. The second part of the book presents an overview of cutting-edge detection techniques to identify emerging biotoxins in several matrices. Readers will find an authoritative overview of the recent developments in nanotechnology and microfluidics (nanomaterial-based systems), and biosensors (immunosensors, receptor-based biosensors, and cell-based biosensors). The book also covers other detection techniques applied to food such as fluorescent, colourimetric, electrochemical, photoelectrochemical, and electrochemiluminescent techniques. Given its breadth, the book appeals to researchers, academics, and students interested in biotoxins, their pharmacological importance and their impact on agriculture and human health.

This book aims to provide a comprehensive and timely review of new findings in motoneuron research. Recent findings have revealed that motoneurons are more complex and have more extensive functions than previously imagined. Some of the molecular and genetic pathways that orchestrate the development of motoneurons have been discovered, as have the mechanisms responsible for the selective innervation of muscles by specific pools of motoneurons. These novel findings are revolutionizing ideas about the function of motoneurons and have important implications for motoneuron disease. Chapters from several of the foremost figures in the field are included in this book and will emphasize how basic science is the engine driving the discovery of novel treatments for degenerative motoneuron diseases. Cutting edge developments in the use of pluripotent stem cells to correct motoneuron disease will be also be covered. This book would be useful to students of basic motoneuron physiology, locomotor behavior and motor control. This book would also be of interest to professional neuroscientists, neurologists, and neurosurgeons.

This book focuses on the new and old methods for the synthesis of various heterocycles using Lawesson's reagent. The book covers an important and rapidly growing branch of heterocyclic chemistry and can serve as a guide to those who are completing their education and are about to enter the job market. Students will be able to find all Lawesson's reagent-assisted protocols for the synthesis of heterocycles in one place. This feature of the book provides an important benefit, because sometimes users want to see all the possibilities and relevant information for making a particular compound using one particular reagent. The purpose of this valuable resource is to provide the knowledge not only to students but also to pharmacologists, biochemists, organic and medicinal chemists, researchers, and academic professionals for easy access to synthetic protocols for different heterocycles using Lawesson's reagent. The book will be greatly helpful for everyone involved inthe field and can pave the way for better understanding and quantification of heterocycle synthesis.

This book focuses on the significance and implications of Calcium (Ca2+) transport machinery in the plant cell in generating alternating Ca2+ levels and impacting the cell's physiological, biochemical and developmental processes. In the following sections, the concept of Ca2+ homeostasis, Ca2+ signature, various Ca2+ transport protein families and conductance systems would be discussed in detail- elucidation of their functional characterization, structure, mechanism, sub-cellular localization and specific physiological roles in ensuring Ca2+ homeostasis. Also, the aspect of Ca2+ as a “signaling hub” –transducing distinct plant responses to diverse environmental stimuli, Ca2+ binding proteins, and the tools used in studying these proteins are explained in brief to paint a holistic picture of Ca2+ transport in plant systems. This has resulted in an elaborative literature account to serve as a staple by providing recent insights and advance knowledge surrounding genetic and molecular dissection of Ca2+homeostasis maintenance mechanisms and extant Ca2+ transport systems in plants.

This book provides an overview of our current understanding of polyembryony in insects. The study of polyembronic insects has advanced considerably over the last several decades.The book shows the exciting potential of polyembryonic insects and their impact on life sciences. It describes the mechanisms of polyembryogenesis; tissue-compatible invasion of the host, which is the first case of compatible cellular interaction between phylogenetically distant organisms without rejection; the sex differences in defense; and the environmental regulation of caste structure. The first book devoted to polyembryony in insects, it draws on the author's research on polyembryonic wasps from 1990 to the present day, covering various topics such as polyembryogenesis in vitro, host-parasite interaction, sex differences in soldier function/humoral toxic factor, and the transcription analysis of polyembryogenesis.It is intended not only for researchers in the field of entomology, parasitology, ontogeny, reproductive biology, developmental biology, sociobiology, and evolutionary developmental biology (Evo-Devo), but also for postgraduate students in these fields.

This is the 2nd edition of a very well received and popular book that reflects the current state-of-the-art of the ongoing research avenues concerning the hippocampus and processing units bridging the gap between single cell activity, network activity and global brain function. It aims to provide a methodology to anyone interested in developing microcircuit level models of the hippocampus. The book is divided into two thematic areas: (I) Experimental background and (II) Computational analysis. In part I, leading experimental neuroscientists discuss the morphological, physiological and molecular characteristics as well as the connectivity and synaptic properties of the various cell types found in the hippocampus. Behaviour-related ensemble activity patterns of morphologically identified neurons in anesthetized and freely moving animals provide insights on the function of the hippocampal areas. In part II, computational neuroscientists present models of thehippocampal microcircuits at various levels of detail (e.g. single cell level, network level, etc.). Synaptomics and connectomics models of hippocampal structures are initially discussed. Then, network models of memory, rhythm generation and spatial navigation are presented, followed by abstract and biophysical models of synaptic plasticity. Network models of hippocampal implicated disorders (epilepsy and schizophrenia) are then detailed and how their network topologies, connectivities and activities change in these diseases. Finally, two chapters are dedicated to describing simulator environments of single neurons and networks currently used by computational neuroscientists in developing their models and modelling tools to parametrically constrain them. This engaging volume is invaluable to experimental and computational neuroscientists, electrical engineers, physicists, mathematicians and others interested in developing microcircuit models of the hippocampus. Graduate level students and trainees in all of these fields can find this book a significant source of information.

This book covers key topics in polyamine research from a range of organisms, including plants, mammals, and prokaryotes such as bacteria and archaea. The book provides an introduction to general concepts in the field of polyamine research, as well as more detailed information. With the availability of genome sequence data from a broad range of organisms, the evolution of the genes involved in polyamine metabolism is discussed. The mode of action of polyamines has been shown to be dependent on cation channels, and this mechanism is described in the book. The origin of polyamine transporters (from bacteria, yeasts, and plants) is described. The various effects of polyamines on growth and survival are also documented. The book details the mechanisms of polyamine homeostasis and the role of polyamine molecules as precursors of secondary metabolites such as plant alkaloids and toxins derived from spiders and wasps. The role of polyamines in longevity and disease is discussed. A link between polyamine contents and cancer progression is reported, as is the use of polyamine metabolites as diagnostic markers in the initial stages of cancer. Moreover, a novel approach that utilizes the polyamine pathway of a parasite as a drug target in African sleeping sickness is described. Therefore, this book is a valuable resource, both as a textbook for undergraduate and graduate students and also as a reference book for front-line polyamine researchers.

With contributions by numerous experts

The nature.and diversity of presentations at the conference on:'Bee Products: Prop­ erties, Applications and Apitherapy'held at Tel-Aviv on May 26--30, 1996, emphasize the increasing interest of physicians, practitioners, scientists, herbalists, dieticians, cosmeti­ cians, microbiologists, and beekeepers in different facets of bee products. This volume consists of a selection of 31 contributions presented at the conference and which provide information on the present status of our knowledge in this area. In spite of their diversity, they reflect the mainstream of the conference, namely:'Imported'Prod­ ucts (honey, pollen and propolis), Exocrine Secretions of Workers (venom, royal jelly). Toxicity and Contaminants, Quality Control, Marketing, Apitherapy, Cosmetics, etc. Since antiquity, honey as well as other bee products were used as food, as a cure for ailments of humans and animals, and as cosmetics. We hope that this volume will contribute to interdisciplinary studies on chemical composition, pharmacological effects, nutrition, and other aspects of bee products. Critical and unbiased experimental research may unravel the yet unknown composition and mode of action of bee products and elucidate many unanswered questions. The noteworthy features of this conference were the participants from all parts of the world and of different cultural backgrounds, who shared their keen interest and curios­ ity regarding honey bees and their products. We thank all of them for their personal con­ tribution to the success of this conference.

The research field of somatosensory processing in mammals has experienced revolutionary changes in recent years. Accumulation of basic and clinical data has greatly accelerated, and new phenomena have emerged. With the aid of new, refined methods, molecular and cellular changes have been described, underlying the signal transduction-transmission between the internal/external environment and the central nervous system have been described. The discovery of the interaction between the nervous and the immune system has, for example changed our view on the development of inflammatory diseases, while the cloning of genes encoding different trophic factors has boosted studies revealing profound changes in the regeneration of neurons, and induction of changes in phenotype. The study of the pre-and postsynaptic modulation of transmitter release, and the examination of the combined effects of amino acid and peptide transmitters has become recently possible by using cultured cell lines and in vitro techniques. Although it is in embryonic state, computational properties of single DRG cells under normal and pathological conditions are being investigated. Results soon or later will have a great impact on pain research and consequently ultimately in clinical pain management. This brief introduction indicates how our knowledge of the somatosensory system has increased dramatically recently. However, many investigators cultivate only a very specific field in the growing area of somatosensory research and find it difficult to integrate a more universal knowledge of their work.

Proceedings of the European Neuroscience Association Satellite Symposium held in Fillerval, France, August 27-31, 1989

This volume is dedicated to Professor Ullrich Trendelenburg. It contains the proceedings of a symposium which was held in his honour on the occasion of his retirement and took place March 22-24, 1991 in Wiirzburg. Ullrich Trendelenburg was the head of the Department of Pharmacology at Wiirzburg University from 1968 till the end of March 1991. He is famous internationally for his contributions to the physiology and pharmacology of the autonomic nervous system, and his impact on pharmacology in general throughout the world has been outstanding. The various phases of his life and his career have been delineated recently by Youdim and Riederer (Journal of Neural Transmission; Suppl. 32, 1990). The articles included in this volume reflect a considerable range of current research work dealing with various aspects of neuropharmacology, i. e., the field of research Ullrich Trendelenburg has influenced most. One or more authors of each chapter are either former or present students and coworkers or close friends of Ullrich Trendelenburg. The first section is devoted to the synthesis and metabolism of catecholamines as well as to the mechanisms by which amine transmitters are removed from the extracellular fluid; three chapters deal with the two types of extraneuronal uptake of catecholamines. The second section concentrates on the release of catecholamines in the peripheral and the central nervous system, the regulation of transmitter release and the noradrenaline-ATP co-transmis­ sion. The third section deals with the pharmacology of various receptors, including agrenoceptors, adenosine, 5-HT and glutamate receptors.

Cell signalling lies at the heart of many biological processes and currently is the focus of intense research interest. In multicellular organisms, it is central to how different types of cell communicate with each other and how they detect and respond to extracellular signals. Intercellular communication is vital to single-celled organisms as well, allowing them to respond to environmental cues and signals. To date, much of the understanding of signalling mechanisms has come from research on specific cell types (eg mouse lymphocyte and cardiomyocyte) or on organisms in which communication systems such as nervous and endocrine systems are well established. This volume therefore aims to'fill the gap'by concentrating on'simple organisms'where the elements of those signalling systems first evolved. Many of the groups covered contain important pathogens or parasites, and the potential for manipulating signalling pathways for therapeutic intervention will be highlighted.

Not since the late 1970s has a single work presented the biology of this heterogenous group of secondary alkaloids in such depth. Alkaloids, a unique treatise featuring leaders in the field, presents both the historical use of alkaloids and the latest discoveries in the biochemistry of alkaloid production in plants alkaloid ecology, including marine invertebrates, animal and plant parasites, and alkaloids as antimicrobial and current medicinal use. Highlights include chapters on the chemical ecology of alkaloids in host-predator interactions, and on the compartmentation of alkaloids synthesis, transport, and storage. Extensive cross-referencing in tabular format makes this volume an excellent reference.

Intoxication of humans and animals has become increasingly important in recent years as has contamination of the environment by a variety of chemicals. In order to develop effective means by which such intoxication and contamination can be properly handled, it is imperative to know how these environmental agents act in humans and animals. Despite studies conducted by various investigators, the mechanisms of action of these environmental agents have not been fully elucidated. Insecticides are by no means an exception in terms of the seriousness of the problem and of the urgency of the need for such information. In order to complete a picture of the effects of any particular insecticide, it is of utmost importance that its actions at various levels ranging from those of molecules to whole animals be analyzed and synthesized. To understand the toxicological action on animals or humans, it is not sufficient to know the action at each level only. The actions at various levels must be integrated to construct a picture of the toxic effect on the intact organism. However, in spite of the large body of information that has been accumulated during the past few decades, little or no attempt has been made to integrate experimental data obtained at the molecular, cellular, organ, and animal levels together in order to define the whole picture of insecticidal action.

This Festschrift volume in honor of Professor Alexander Karczmar is the outcome of a three-day symposium entitled'Neurobiology of Acetylcholine'held at Loyola University Medical Center from June 3 to 5, 1985. This volume serves two purposes. It expresses the respect and admiration of the contributors to Alex Karczmar, and it provides a forum for detailing recent advances in the cholinergic field which has attracted the undivided and untiring attention of Dr. Karczmar over some 40 years. During this period, the cholinergic system has grown from its infancy to become one of the most studied and understood transmitter systems today. Dr. Karczmar's interest in cholinergic system is appropriately reflected by the range of topics, molecular, cellular, developmental, behavioral and toxicological, that were discussed here. A detailed synopsis of Dr. Karczmar's research and his contributions to the field of cholinergic systems can be found in the following chapter by his close friend and colleague, Dr. George Koelle. We would like to take this opportunity to thank the enthusiastic responses of the participants making this Festschrift a memorable event.

This volume comprises the proceedings of the First International Rehovot Conference on Modem Agriculture and the Environment, held at the Rehovot Campus of the Faculty of Agriculture, the Hebrew University of Jerusalem, Israel, 2-6 October 1994. The conference, first in a series intended to be convened in Rehovot at 4-5 year intervals to address various aspects of the interaction of agriculture and the environment, was initiated, organised and carried out under the auspices of the Faculty of Agriculture, the leading academic institution in agricultural and environmental studies in Israel. It featured four keynote addresses, 39 invited lectures, 40 submitted papers, and 62 posters. Of these, 51 articles, written by 122 contributing authors from 14 countries, were selected by the editors to be presented in this book. All through the twentieth century, and especially ever since the advent of the Green Revolution, modem agriCUlture has been striving to feed and clothe the ever­ increasing multitudes of the human species through improved technology, relying heavily on tremendous inputs of fertilisers, pesticides, and various other agrochemicals. Undoubtedly, this has been a great blessing to mankind, and enormous strides have indeed been made in the never-ending struggle against starvation, but these have been achieved at a very steep price of increased environmental deterioration. In fact, modem agriculture has become one of the major factors contributing to the degradation of the world's fragile biosphere.

The purpose of this dictionary is to provide a convenient and affordable personal desk reference resource. The authors, who have many years experience in pharmacological research, teaching and editing, recognized a need for a single up-to-date volume encompassing material that hitherto could be gathered only from a well-stocked library. This book comprises two main sections: an A-Z listing of drugs and their properties; and a descriptive glossary of technical terms. The level and scope of this reference material will make it essential for pharmacologists and medicinal chemists, from the graduate student to established worker. It should also be valuable to workers in allied biomedical diSCiplines, such as biochemistry and physiology, medical students and science writers and editors. Scope The dictionary is centred on pharmacologically active agents. Workers in drug-related diSCiplines need to correctly identify individual agents from an arsenal of pharmacologically active compounds, each with a number of alternative drug names according to the country or naming convention.

Cells maintain uneven distribution of Na, K and Ca ions across the cell membrane and membranes of intracellular organellae. Cells exert their functions by allowing for some ion to cross the membrane through ion channels which either produces an electrical effect across the membrane or switches on a series of chemical or physicochemical reactions. This is a comprehensive book about these vitally important ion channels with detailed description of the molecular structure and function and especially of activators and inhibitors. All chapters are written by renowned specialists in their field.

NEUROTOX'91 was the fourth meeting in a series which started in 1979. The'91 meeting, like its predecessors, was held under the patronage of the Society of Chemical Industry, and despite the unfortunate proximity of hostilities in the Arabian Gulf attracted a truly international mix of industrial and academic pesticide scientists. This volume contains the text of invited papers read at the meeting and presents the dramatic developments which so excited those who attended. The potential of molecular neurobiology for gaining knowledge of target sites for neurotoxicants is now starting to be realised. These studies, in conjunction with developments in molecular imaging and modelling, provide new oppor­ tunities for chemists and biologists to gain insights into molecular interactions underlying intoxication. Molecular techniques have also enabled rapid ad­ vances on a second front, where the cloning of genes controlling pesticide resistance should have a profound impact on our understanding of this commercially important problem. The understanding of molecular events will undoubtedly be vital in future developments in chemical control of pests; however, the value of understand­ ing the way in which the nervous system controls behaviour and how behaviour can be modified by chemicals of bath synthetic and natural origins was highlighted. Natural products and their synthetic analogues have continued to provide new and interesting molecules which are already proving their worth as tools for the neuroscientist and may offer leads for commercial synthesis.

The attractions of invertebrate nervous systems have long been appreciated by neurophysiologists. Indeed some of the milestones in our understanding of nervous systems have their foundations in experiments done on invertebrate preparations, typified by the role of the squid axon in dissect­ ing the events that constitute the action potential. More recently we have seen how the relatively simple nervous system of Aplysia has permitted new insights into the molecular mechanisms of memory and learning. Neurochemists, however, have not been enthusiastic about invertebrate tissues as their experimental material. Much of the biochemical information on invertebrate nervous systems that has accrued has been incidental, almost as a by-product of what were primarily physiological investigations. Fortunately the field is changing, and research groups are making a positive choice to turn to invertebrate tissues. Two important factors have contributed to this. First, the study of analogous systems in invertebrates and vertebrates can tell us much about the evolution of nervous systems. The application of the techniques of molecular genetics to the study of such molecules as receptors and ion channels can provide detailed information about their composition that, in turn, allows us to better understand their function. By extending such studies to the invertebrates we should be able to understand how such systems have developed. Secondly, invertehrate pests are responsible for enormous losses of agricultural crops and are major vectors of disease in man.

The development of pesticide resistance in arthropod pests, plant pathogens and weeds can be viewed and studied from two contrasting perspectives. At a fundamental level, resistance provides an almost ideal example of adaptation to withstand severe environmental stress. Population geneticists, biochemists and, most recently, molecular biologists have cast considerable light on the nature of this adaptation in diverse taxonomic groups, and on factors determining its selection and spread within and between populations. Unlike most evolutionary phenomena, however, resistance is also of immediate practical and economic significance. Not only has the number of resistant species continued to increase inexorably, but there has been an alarming increase in the severity and extent of some resistance problems. Cases of organisms resisting virtually all available pesticides are by no means uncommon, and pose a formidable challenge in view of present difficulties in discovering and developing novel chemicals. Although most occurrences of resistance were initially monofactorial, resistance now frequently involves a suite of coexisting mechanisms that protect organisms against the same or different pesticide groups, and may even predispose them to resist new, as yet unused chemicals.

This book disseminates current information pertaining to the modulatory effects of foods and other food substances on behavior and neurological pathways and, importantly, vice versa. This ranges from the neuroendocrine control of eating to the effects of life-threatening disease on eating behavior. The importance of this contribution to the scientific literature lies in the fact that food and eating are an essential component of cultural heritage but the effects of perturbations in the food/cognitive axis can be profound. The complex interrelationship between neuropsychological processing, diet, and behavioral outcome is explored within the context of the most contemporary psychobiological research in the area. This comprehensive psychobiology- and pathology-themed text examines the broad spectrum of diet, behavioral, and neuropsychological interactions from normative function to occurrences of severe and enduring psychopathological processes.

This volume critically examines the functional actions of the kainate‑type glutamate receptors (KARs). Following on from the larger body of work on the NMDA‑ and AMPA-type ionotropic glutamate receptors (GluRs), studies with KARs have consistently thrown up exceptions to general rules about synaptic modulation. Contributors herein provide an insight to the idiosyncracies that now almost typify the KAR field. The fascinating insights provided in this volume serve to encourage searching mechanistic questions.

Circulation of blood is vital for the survival of vertebrates, including man. Mainly, it plays an important role in carrying food nutrients and oxygen to every tissue and organ and in removing all waste products and carbon dioxide. Any imbalance in the hemostatic and cardiovascular systems can lead to death and severe debility. A number of animals have developed mechanisms to target these systems and exploit the vulnerability. In some species (for example, snakes), such mechanisms are used to immobilize and kill the victim/prey, whereas in others (for example, insects, such as leaches, mosquitoes and ticks), they are used to provide a continuous supply of blood. These mechanisms include, but are not limited to, procoagulant and anticoagulant actions that affect the coagulation cascade and platelet aggregation, as well as altering vasodilatory responses. In all these various animals, these mechanisms have evolved to perfection over millions of years to support their survival. In last 3-4 decades, due to the efforts of scientists from various backgrounds including biology, protein chemistry, molecular biology, pharmacology, hematology, and structural biology, significant progress in understanding the structure-function relationships, as well as the mechanism of action have been made in a number of exogenous factors that affect blood coagulation, platelet aggregation and vasodilation from various animals. These exogenous factors have contributed significantly to the development of research tools as well as providing new therapeutic agents. With the increase average age of the population coupled with changes in life style in recent years, there has been a significant increase in cardiovascular and hematological disorders. Thus scientists in both academic institutions as well as the pharmaceutical industry are developing better therapeutic agents to improve the quality of life. This impetus has lead to the search for novel agents from various sources that interfere withcardiovascular and hematalogical processes. Although at first glance exogenous factors appear to function as ‘villains', several life-saving drugs have been developed based upon these factors. Such drugs or drug leads include those that inhibit the angiotensin converting enzymes (Captopril and Enalapril), that block platelet receptors (Eptifibatide and Tirofiban), or that digest thrombotic plugs (Alfimeprase and bat plasminogen activator) to name a few. Several new and exciting success stories are currently unfolding. In this book, recent studies on some of the exogenous factors that play crucial roles in cardiovascular and hematological disorders are reviewed in order to consolidate the efforts in this area of research and to recruit new, talented researchers. The 25-30 review chapters, each written by experts in their field, compiled herein are devoted to exogenous factors affecting platelet aggregation, anticoagulant and procoagulant proteins, fibrinolytic proteins and hypotensive agents (For details see, Contents of the Book). This book is intended to help to create elevated awareness and enthusiasm in the field of exogenous factors. I believe that this book will provide greater impetus to the search for novel proteins based on naturally occurring exogenous factors. This will be the first book dealing extensively with exogenous factors in the last 25 years. The book will provide a ready reference to the different approaches used to solve complex problems in protein chemistry and pharmacology of exogenous factors. The book will update our understanding of the structure-function relationships and mechanisms of action of exogenous factors and provide great insights into future directions for solving the remaining challenges.

Rich in detail, Hippocampal Microcircuits: A Computational Modeler's Resource Book provides succinct and focused reviews of experimental results. It is an unparalleled resource of data and methodology that will be invaluable to anyone wishing to develop computational models of the microcircuits of the hippocampus. The editors have divided the material into two thematic areas. Covering the subject's experimental background, leading neuroscientists discuss the morphological, physiological and molecular characteristics as well as the connectivity and synaptic properties of the various cell types found in the hippocampus. Here, ensemble activity, related to behavior, on the part of morphologically identified neurons in anesthetized and freely moving animals, lead to insights into the functions of hippocampal areas. In the second section, on computational analysis, computational neuroscientists present models of hippocampal microcircuits at various levels of detail, including single-celland network levels. A full chapter is devoted to the single-neuron and network simulation environments currently used by computational neuroscientists in developing their models. In addition to the above, the chapters also identify outstanding questions and areas in need of further clarification that will guide future research by computational neuroscientists.

Marine organisms produce a wide array of toxins, many of which are not only structurally unusual, but also show potent and interesting modes of action. Since the discovery of tetrodotoxin, a pufferfish toxin, as a potent and selective blocker of Na+ channels in 1964, it has been widely used as a research tool in pharmacological and physiological research. This has led to the identification of a number of important biological functions for Na+ channels. In recent years, much biological research has been carried out at molecular and cellular levels, and therefore selective inhibitors of enzymes and selective antagonist/agonists of receptors and channels have become increasingly important research tools. Accordingly, interest in using such compounds as reagents has increased. Marine toxins are some of the most popular research tools and have already contributed much to our understanding of biological processes and disease mechanisms.

With contributions by numerous experts