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In this book, the authors present current research in the study of germ cells. Topics include the molecular signature and sub-cellular machinery of metazoan gametogenic stem cells; recent advances in understanding germ cell-specific organelles and their functions; low-dose radiation induces apoptosis in male germ cells of mice and attenuates it in type 1 diabetes rats; oocyte nuclear structure during mammalian oogenesis; and chromatoid body assembling and nuclear cycles.

A concise primer that complicates a convenient truth in biology—the divide between germ and somatic cells—with far-reaching ethical and public policy ramifications. Scientists have long held that we have two kinds of cells—germ and soma. Make a change to germ cells—say using genome editing—and that change will appear in the cells of future generations. Somatic cells are “safe” after such tampering; modify your skin cells, and your future children's skin cells will never know. And, while germ cells can give rise to new generations (including all of the somatic cells in a body), somatic cells can never become germ cells. How did scientists discover this relationship and distinction between somatic and germ cells—the so-called Weismann Barrier—and does it actually exist? Can somatic cells become germ cells in the way germ cells become somatic cells? That is, can germ cells regenerate from somatic cells even though conventional wisdom denies this possibility? Covering research from the late nineteenth century to the 2020s, historian and philosopher of science Kate MacCord explores how scientists came to understand and accept the dubious concept of the Weismann Barrier and what profound implications this convenient assumption has for research and policy, from genome editing to stem cell research, and much more.

This volume covers the current knowledge base on the role of signaling and environmental pathways that control the normal development of germline stem cells, meiotic progression of oocytes, events of oocyte maturation and fertilization, and the birth of an embryo.Germ cells are uniquely poised to sustain life across generations through the fusion of oocyte and sperm. Because of the central importance of germ cells to life, much work has been dedicated to obtaining a clear understanding of the molecular and signaling events that control their formation and maintenance. Germ cells are set aside from somatic cells in the embryo and go through specialized meiotic cell cycles as the animal matures. These cell cycles are interspersed with long periods of arrest. In human females, meiosis I is initiated in the fetus. At birth, oocytes are arrested in meiosis I; after puberty, every month an oocyte initiates meiosis II – ovulation. Upon sperm availability these cells are fertilized, generate an embryo, and the cycle-of-life continues. During meiotic I progression and arrest, the fitness of oocytes and their progeny are likely influenced by environmental cues and signaling pathways.A lot of recent work has focused on understanding the mechanisms that regulate oocyte fitness and quality in humans and vertebrates. Much of our understanding on the events of meiosis I and germline stem cell populations comes from work in invertebrates, wherein the germline stem cells produce oocytes continuously through adult development. In both inverbrates and vertebrates nutritional and signaling pathways control the regulation of stem cells in such a manner so as to couple production of gametes with the nutritional availability. Additionally, mature oocytes arrest both in meiosis I and meiosis II, and signaling and nutritional pathways have been shown to regulate their formation, and maintenance, such that despite long periods ofarrest, the oocyte quality is assured and errors in chromosome segregation and varied cytoplasmic events are minimal.

The Immortal Germline, Volume 135 in the Current Topics in Developmental Biology series, highlights new advances in the field, with this new volume presenting interesting chapters on a variety of topics, including Balbiani body, germ plasm and polarity, Wolbachia and the germline, Human germ line biology, Reproduction/immunity and sperm success, Mammalian spermatogenesis, Reproduction/regeneration and germ cells in planarians, Germline stem cell homeostasis, Germline soma interactions/sex determination, Reconstituting the mouse germ-cell specification pathway in vitro, Maternal Germ line inheritance of mitochondria, Transposon strategies, and more. - Provides the authority and expertise of leading contributors from an international board of authors - Presents the latest release in the Current Topics in Developmental Biology series - Includes the latest information on germ cells

Kommt es bei der Durchführung einer reproduktionsmedizinischen Maßnahme zu einem Zwischenfall, bei dem Keimzellen oder Embryonen vertauscht werden, sind nicht nur die tatsächlichen, sondern auch die rechtlichen Auswirkungen drastisch. Neben der Frage, ob und wie der Arzt den Vorfall aufklären kann, sehen sich Betroffene insbesondere mit abstammungsrechtlichen Verwerfungen und haftungsrechtlichen Überlegungen konfrontiert. Moritz L. Jäschke zeigt auf, dass die gegenwärtige Rechtslage sowohl im Bereich der Prävention als auch mit Blick auf die Rechtsfolgen eines solchen Vorfalls lückenhaft ist. Diesen Missstand versucht er mithilfe detaillierter Regelungsvorschläge aufzulösen.

Scientists investigating germ cells have, over the past 15 years, originated discoveries and innovations that give us valuable insights into the mechanisms that regulate not just stem cell function, but human development in its widest sense. With contributions from some of the leading researchers in the field, Male Germline Stem Cells: Developmental and Regenerative Potential assesses the implications of these discoveries for understanding the fundamental biology of germline stem cells as well as their potential for human stem cell-based therapies. This monograph covers many of the fundamental issues now being explored by today's generation of stem cell researchers, including the field's potential for regenerative medicine. Ranging from an assessment of the pluripotency of primordial germ cells and their possible applications in treating testicular cancer, to the recovery of once-mordant fertilization-competent sperm, this volume has it all. It is a reference point for any scientist involved in related research as well as being a timely summation of what could prove to be a hugely exciting and very fruitful area of inquiry.

Der gezielte Eingriff in die menschliche Keimbahn galt lange Zeit als Phantasma. Doch seit Beschreibung des CRISPR/Cas Systems als potentielle'Genschere'im Jahr 2012 scheint die Idee der präzisen Veränderung des Genoms menschlicher Keimzellen und Embryonen in greifbare Nähe gerückt zu sein. Während bereits mehrere Experimente mit dieser Methode an menschlichen Embryonen im Ausland publiziert wurden, ist jedoch die Diskussion um die medizinischen, ethischen und gesellschaftlichen Implikationen einer möglichen Keimbahntherapie längst nicht abgeschlossen.Dieses Buch umfasst eine detaillierte und kritische Betrachtung einschlägiger und nicht selten altbekannter Argumente in bioethischen Kontroversen und leistet deren Einordnung in den spezifischen Kontext der Debatte um einen Eingriff in die menschliche Keimbahn. Es beinhaltet eine profunde Nutzen-Risiko-Darstellung, die sowohl individuelle als auch gesellschaftliche Aspekte berücksichtigt, und bietet eine differenzierte Auseinandersetzung mit den unterschiedlichen Positionen in der Diskussion um die umstrittene Intervention.

The Novartis Foundation Series is a popular collection of the proceedings from Novartis Foundation Symposia, in which groups of leading scientists from a range of topics across biology, chemistry and medicine assembled to present papers and discuss results. The Novartis Foundation, originally known as the Ciba Foundation, is well known to scientists and clinicians around the world.

Germ cells in sexually reproducing metazoa, through the germline lineage, are the route by which genetic material and cytoplasmic constituents are passed from one generation to the next in the continuum of life. Chapters in this book review germ cell development in the model organism Caenorhabditis elegans, discussing the biology, the genetics and the molecular mechanisms for various processes, as well as drawing comparisons with other organisms. Processes discussed include specification of germ cell fate, meiosis, gametogenesis, environmental/ physiological controls, epigenetics and translational control, fertilization and the oocyte-to-embryo transition. This book thus provides a comprehensive picture of the germline lineage and the continuum of life for the worm.

This book provides, for the first time, a detailed, up-to-date, holistic approach to the pathology and biology of germ cell tumors. The main focus is the complex histopathology of these tumors, but special considerations are also given to their morphologic variations in relation to age, gender and organ. Critical updates are provided on terminology and classification; the discussion of biology and pathogenesis includes references to many molecular genetic and immunohistochemical findings from recent stem cell research. Individual chapters are devoted to germ cell tumors at different anatomic locations, including not only the ovaries and testes but also the mediastinum and central nervous system, and pediatric tumors. All of the contributing authors are opinion leaders from universities of excellence in Europe and the United States. This monograph will be of wide interest to practitioners and researchers in many fields of medicine, including pathology, gynecology, urology, and pediatrics, as well as stem cell scientists.

Germ cell research has produced enormous advances in recent years and more recently has entered into an explosive phase of new discoveries with the introduction of transgenic technologies and nuclear cloning. In Germ Cell Protocols, expert laboratory investigators describe in step-by-step detail a series of powerful techniques for the molecular and genetic analysis of germ cells in a variety of different reproductive systems. Chosen for their proven success in advancing our understanding of germ cells, these methods cover sperm and egg activation, motility, fertilization, nuclear development, nuclear cloning, the molecular characterization of specific events, the imaging of cell structures, and the cryopreservation of germ cells. Volume 2: Molecular Embryo Analysis, Live Imaging, Transgenesis, and Cloning focuses on molecular egg analysis, live egg imaging, nuclear cloning, oocyte cryopreservation, and nuclear transfer. Highlights include the identification and characterization of Oct-4, germline chromatin silencing by RNAi, cDNA subtraction and cloning in the field of trophoblast/placental development, and selective ablation. There are also methods for PCR-based cloning, differentiating embryonic stem cells into embryonic bodies, live imaging of mammalian embryos using multiphoton microscopy, and the cloning of pig, cattle, rabbit, and mouse oocytes. Each readily reproducible protocol is described in step-by-step detail and contains an introduction outlining the principle behind the technique, lists of equipment and reagents, and tips on troubleshooting and avoiding known pitfalls. An accompanying earlier volume, Sperm and Oocyte Analysis, focuses on sperm cells, oocyte analysis, oocyte maturation, fertilization, and preparation techniques. Comprehensive and cutting-edge, Germ Cell Protocols offers both novice and established researchers a gold-standard collection of hard-to-find methods for high impact research, diverse procedures that are easy-to-follow, well-illustrated, and allow a cross-species transfer of knowledge from lower vertebrates to higher mammalian systems.

The completion of the human genome and technological advances developed by the Human Genome Project have dramatically changed our understanding of the mechanisms underlying the development and differentiation of male germ cells, and our ability to investigate such mechanisms. This book is a timely document of advances made in the field of male gonad and germ cell research in the postgenomic era.The coverage includes the role of Y chromosome genes in male reproduction, gene expression in spermatogonial stem cells and male germ cells, and the regulation of germ cell genes in reproduction and in germ cell tumors.

A gold-standard collection of readily reproducible techniques for the molecular and genetic analysis of germ cells in a variety of different reproductive systems. Volume 1: Sperm and Oocyte Analysis focuses on sperm cells, oocyte analysis, oocyte maturation, fertilization, and preparation techniques. Highlights include in vitro maturation and fertilization of human, porcine, and canine oocytes; the cryopreservation of sperm cells; establishment of an in vitro spermatogenesis system; visualization of sperm accessory structures; and motility assays of stallion spermatozoa. Each readily reproducible protocol is described in step-by-step detail and contains an introduction outlining the principle behind the technique, lists of equipment and reagents, and tips on troubleshooting and avoiding known pitfalls.

Pathobiology of Human Germ Cell Neoplasia is a state-of-the-art compendium on a very recent branch of tumor biology. It offers an awareness and understanding of germ cell tumors: from the earliest stages to their va- rious differentiations. Original data for this volume was supplied by experts in the fields of pathology, developmental biology, genetics, molecular biology and other related fields. This compilation of knowledge provides information necessary to persons working in clinical and preclinical areas.

In the last few years, the adoption and worldwide proliferation of clinical procedures for medically assisted conception have been associated with the examination and analysis of spermatozoa, oocytes and early embryos under a variety of in vivo and in vitro conditions. These analyses have enabled correlations to be made between the behavior of gametes, the pattern of early embryonic development and the initiation of a normal pregnancy. Collectively, the findings have not only enormously increased our understanding of the process of early human development, but also have provided new insights into the origin and causes of reproductive failure in man. The research presented in this volume describes recent results derived from the study of normal and abnormal patterns of human spermatogenesis, oogenesis and early embryogenesis. The chapters discuss aberrations in morphodynamic and morphophysiological processes that have clinical relevance in human infertility and conception. Two of the chapters describe, respectively, the basic research that allows the cryopreservation of human oocytes and embryos, and the development of in vitro systems that permit the study of cell differentiation and interaction during the peri-implantation period. When relevant, each chapter extrapolates findings from in vitro experimentation to the comparable situation that is observed in vivo.

Advances in the development and application of electron microscopic techniques have occurred recently such that the electron microscope has evolved to become an essential tool in both basic and clinical research. Use of this instrument has contributed significantly to the formation of new perspectives and concepts concerning cell fine structure. These structural perspectives are now being integrated with specific functional, biochemical and pathophysiological events and processes of cells and tissues. Most recently, utilization of innovative electron microscopic techniques such as freeze-fracture, freeze­ etching, and scanning and high-voltage electron microscopy offers both the basic and clinical scientist potentially fundamental insights into many morphodynamic processes related to the activities of cells and tissues. Such an approach has been especially rewarding when applied to the dynamic events of gametogenesis and early embryonic development. The chapters comprising this book have been selected and edited with the aim of providing an up-to-date and comprehensive account of the most important aspects of vertebrate gamets and embryos as revealed by the integration of several different submicroscopic methods. The organization of the chapters is designed to indicate present gaps in our knowledge of the developmental and reproductive biology of gametes and the developing embryo and possible Iines of research which may lead to a lessening of these gaps.

The magnitude of the threat to the human genetic material posed by environmental agents has not as yet been fully determined. Never­ theless, the potential hazards of many chemicals have been identi­ fied by studies on lower organisms. However, too little is known regarding the comparability or lack of it between the metabolic pathways available in such organisms and those in man. Although at present there is great public concern for what is considered by some as the excessive use of laboratory animals in toxicological testing, it seems clear that the usage of mammalian systems may be deemed necessary. It has been proposed that cell culture systems might suffice to meet this need, however, such approaches cannot match the complexity of physiological occurances that are present in the intact animal. For studies of genetic effects, some non-invasive human test systems are presently available. These do not, however, meet the re­ quirements for extensive laboratory studies. In order to assess the risks to humans of environmental factors such laboratory investiga­ tions are essential. Therefore, for the forseeable future reliance on experiments using laboratory animals will be necessary. This Volume, which contains the proceedings of a workshop which was held at the National Institute of Environmental Health Sciences, March 29-31, 1982, explores the existing methodologies and their utility for risk estimations. It covers the most well developed human systems, as well as the most widely used animal tests.

Unwanted childlessness affects approximately one in six couples worldwide. - though the exact proportion of the predominant cause of the problem remains controversial, according to the World Health Organization (WHO), in nearly 40% of cases the cause can be attributed to the female, in 20% to the male, in 25% to both, and in 15% the cause remains unknown. Based on these?gures, the - cidence of male factor infertility in the general population is approximately 7%. The majority of these men, approximately 30%, experience irreversible idiopathic infertility and cannot father children without some form of medical intervention. Male factor infertility, in addition, may be caused by testicular germ cell cancer, which is known to represent the most common cancer among young men, aged 15 to 35 years, in Western industrialized countries. The number of affected men has increased dramatically over the past 50 years. There is now growing evidence that human testicular germ cell cancer originates from fetal germ cells exhibiting an aberrant programme of gene expression, and tumour progression may be favoured by an aberrant Sertoli cell-germ cell communication.

Scholars discuss the genetic modification of embryonic cells from the viewpoints of traditional Jewish and Christian teaching, considering both the possible therapeutic benefits of this technology and moral concerns about its implementation.We are approaching the day when advances in biotechnology will allow parents to “design” a baby with the traits they want. The continuing debate over the possibilities of genetic engineering has been spirited, but so far largely confined to the realms of bioethics and public policy. Design and Destiny approaches the question in religious terms, discussing human germline modification (the genetic modification of the embryonic cells that become the eggs or sperm of a developing organism) from the viewpoints of traditional Christian and Jewish teaching. The contributors, leading religious scholars and writers, call our attention not to technology but to humanity, reflecting upon the meaning and destiny of human life in a technological age. Many of these scholars argue that religious teaching can support human germline modification implemented for therapeutic reasons, although they offer certain moral conditions that must be met. The essays offer a surprising variety of opinions, including a discussion of Judaism's traditional presumption in favor of medicine, an argument that Catholic doctrine could accept germline modification if it is therapeutic for the embryo, an argument implying that “traditional” Christian teaching permits germline modification whether for therapy or enhancement, and a “classical” Protestant view that germline modification should be categorically opposed. ContributorsLisa Sowle Cahill, Nigel M. de S. Cameron, Ronald Cole-Turner, Amy Michelle DeBaets, Celia Deane-Drummond, Elliot Dorff, H. Tristram Engelhardt, Jr., Thomas A. Shannon, James J. Walter

Current Topics in Developmental Biology provides a comprehensive survey of the major topics in the field of developmental biology. These volumes are valuable to researchers in animal and plant development, as well as to students and professionals who want an introduction to cellular and molecular mechanisms of development. The series has recently passed its 30-year mark, making it the longest-running forum for contemporary issues in developmental biology. - Includes many descriptive figures - Topics covered include the role of mitochondrial function, the use of ARTs to regulate mtDNA disease, nuclear transfer, and more - Latest volume in the series that covers 10 reviews from leading authorities in developmental biology

Recently, expectations of the potential of regenerative medicine have risen because of the exciting results obtained in various areas of research. This book contains contributions from leading researchers in the field who describe their successes and the problems that remain in converting the hopes into concrete therapies. The focus of the book is on the role of stem cells in two main areas -- reproduction and the brain -- described from molecular, cellular, in vivo and clinical perspectives.

Le cancer du testicule a bénéficié d'importantes avancées thérapeutiques transformant radicalement son pronostic. Les protocoles récents ont conduit au développement de traitements conservant l'efficacité thérapeutique tout en privilégiant la qualité de vie et en minimisant les séquelles (comme les troubles de la fertilité) de ces hommes souvent jeunes. Cet ouvrage aborde les différents progrès techniques tant dans le domaine du diagnostic - avec l'apport de l'imagerie moderne et de l'anatomopathologie - que thérapeutique. La place de la chimiothérapie de même que celle de la chirurgie sont largement détaillées, plaçant ainsi l'urologue au coeur de l'équipe pluridisciplinaire prenant en charge ces patients. La qualité de vie est également évoquée en tenant compte de l'incidence du traitement de ces tumeurs sur la fertilité de ces jeunes patients.

The Human Genome Project, discoveries in molecular biology, and new reproductive technologies have advanced our understanding of how genetic science may be used to treat persons with genetic disorders. Greater knowledge may also make possible genetic interventions to'enhance'normal human characteristics, such as height, hair or eye color, strength, or memory, as well as the transmittal of such modifications to future generations. The prospect of inheritable genetic modifications, or IGMs, whether for therapeutic or enhancement purposes, raises complex scientific, ethical, and regulatory issues. Designing Our Descendants presents twenty essays by physicians, scientists, philosophers, theologians, lawyers, and policy analysts addressing these issues from diverse perspectives. In three sections, the authors discuss the short- and long-term scientific feasibility of IGM technology; ethical and religious issues related to safety, justice, morality, reproductive rights, and enhancement; and regulatory issues including the necessity of public input and oversight and the influence of commercialization. Their goal is to open a dialogue engaging not only scholars and scientists but also government officials and concerned citizens. The authors conclude that while IGM cannot be carried out safely and responsibly on humans utilizing current methods, it is important to begin public discussion now to determine whether, and if so how, to proceed.

The series Advances in Stem Cell Biology is a timely and expansive collection of comprehensive information and new discoveries in the field of stem cell biology.Recent Advances in iPSC-derived Cell Types, Volume 4 addresses how different cell types can be derived from induced pluripotent stem cells.Somatic cells can be reprogrammed into Induced pluripotent stem cells by the expression of specific transcription factors. These cells are transforming biomedical research in the last 15 years. The volume teaches readers about current advances in the field. This book describes the use of induced pluripotent stem cells to form different cell types which can be used in cell therapy as well as to model several diseases in vitro, enabling us to study the cellular and molecular mechanisms involved in different pathologies. In recent years, remarkable progress has been made in the obtention of induced pluripotent stem cells and their differentiation into several cellular populations, tissues and organs using state-of-art techniques. This volume will cover what we know so far about the use of iPSCs to derive different cell types, such as: erythroid cells, mucosal-associated invariant T cells, megakaryocytes, cerebral cortical neurons, inner ear cell types, airway epithelial cells, male germ cells, trophoblasts, cardiomyocytes, ßpancreatic cells, and more. The volume is written for researchers and scientists interested in stem cell therapy, cell biology, regenerative medicine, and organ transplantation; and is contributed by world-renowned authors in the field. - Provides overview of the fast-moving field of induced pluripotent stem cell technology, regenerative medicine and therapeutics - Covers the following cell types derived from iPSCs: erythroid cells, mucosal-associated invariant T cells, megakaryocytes, cerebral cortical neurons, inner ear cell types, airway epithelial cells, male germ cells, trophoblasts, cardiomyocytes, ßpancreatic cells, and more - Contributions from stem cell leaders around the world

This book is focused on Sertoli cell physiology and its role in the spermatogenic event. These cells, known as “nurse cells”, are essential for the normal development of germ cells by offering not only physical support and creating an immune-privileged environment, but also for providing nutritional support. The presence of Sertoli cells promotes the establishment of the appropriate microenvironment so that spermatogenesis may occur. Spermatogenesis maintenance in vivo is highly dependent on the metabolic cooperation established between Sertoli cells and developing germ cells. For many years this metabolic cooperation between testicular cells has been disregarded, but recent advances have highlighted the relevance of these processes for male fertility. Thus, the understanding of the functioning and regulation of these metabolic processes is a crucial step to identify key mechanisms associated with Sertoli cell (dys)function and to enlighten their influence on male fertility.

There is no commonly accepted mechanism to explain differentiation of either normal or neoplastic cells. Despite this fact, the organizers of the 3 rd International Conference on Differentiation recognized that there is much emerging evidence which supports the view that both normal cells and many cancer cells share common differentiative processes. Accordingly, the organizers perceived that clinical scientists and developmental biologists would greatly benefit by together considering differentiation. In that way, developmental biologists would be apprised of recent insights in cancer cell biology and the physician scientist would be updated on events in developmental biology and both would gain new understanding of the cell biology of neoplasia. A specific example may reveal the potential value of developmental biologists interacting with cancer physicians. An example chosen at random suggests that probably any paper included in the symposium volume would serve the purpose. Dr. Stephen Subtelny reviewed recent studies by his laboratory concerning germ cell migration and replication in frog embryos. How might those results interest the cancer scientist? Dr. Subtelny showed that primordial germ cells of a fertile graft will reverse their migratory direction and move into a sterile host. Perhaps in this context it would not be inappropriate to state that the germ cells of the graft metastasized into the host. Germ cells from grafts of a different species will populate the previously sterile host gonad.

This book reviews and describrs our own results on varied new and advanced topics. The basic understanding has been created in the initial pages on Ovarian and follicular development which includes such advanced topics as Gap junctions and oocyst development.This shall help the readers to appreciate and understand more recent and advanced trchniques like Ovarian drilling- The activation of dormant oocyte, Foilicle wakeup call (energy waves) energizing it to undergo mitosis and meiosis. Gametogenesis, genome methylation patterns, gene regulation, embryogenesis, gene imprinting.Genetic control of follicular genesis has been incorporated to make use of new reproductive technology for understanding, Oocyte -follicle communication system, C-kit receptors and its legends, and growth factors. Ovuation, fertilization and conceptus development has been reviewed. Mapping and presence of genes like Figla, NoboxL2, Kiti and NT1K2in germ cells and Presence of Foxl2, Kiti genes in somatic cells surrounding germ cells. Mitotic and meiotic exposure effects along with Germ cell biochemical configuration of DNA have been detailed.Endometrial dating, implantation and cotyledon development has been the new focus to understand new mechanisms researched in the past decade. This has not been enshrined in any book till date. Thus most of the information is from research journals or free websites on the topics. Endometrial estrogen, progesterone receptors, blastocyst elongation factors, biochemical factors inclusive of 20 images on implantation have been our own results on the topic. Khatoon and wani 2007, Wani 2009, 2010) early pregnancy establishment and its recognition. Pregnant uterus killer cell convertion to non killer cells, zona specificity, intrauterine growth retardation factors have been the specific aspects of clinical diagnostics and therapy dealt here to facilitate the clinicians with most recent and updated information on the subject. Mammalian fetal physiology, Foetal fluids, Membranes, Cotyledons, Caruncle, Images have been reviwed adding new information to already reviewed information published Wani 2009, 2006, 2007, 2010. Mammalian genetic diagnostic techniques, Nuclear receptors and uterine therapeutics have been special features of the book. Assisted reproductive techniques and their effects on fertility aong with GENETIC ENGINEERING AND CLONING have been discussed in brief. Gestation biology and muscular pulls, Morphological and biochemical changes during gestation Feto-maternal immunology have been reviewed briefy.

This new volume of Current Topics in Developmental Biology covers the area of gametogenesis, with contributions from an international board of authors. The chapters provide a comprehensive set of reviews covering such topics as germline stem cells, signaling modalities during oogenesis in mammals, and genomic imprinting as a parental effect established in mammalian germ cells. - Covers the area of gametogenesis - International board of authors - Provides a comprehensive set of reviews covering such topics as germline stem cells, signaling modalities during oogenesis in mammals, and genomic imprinting as a parental effect established in mammalian germ cells

Higher eukaryotes are characterized by the allocation of distinct functions to numerous types of differentiated cells. Whereas in animals the well-defined, protected cells of the germ line separate early, germ cells in plants differentiate from somatic cells only after many cycles of mitotic division. Therefore somatic mutations in plants can be transmitted via the germ cells to the progeny. There is thus a clear need for somatic tissues to maintain their genetic integrity in the face of environmental challenges, and two types of interactions have been shown to play important roles in the conservation as well as flexibility of plant genomes: homologous recombination of repeated sequences and silencing of multiplied genes. Sensitive methods have been developed that allow greater insights into the dynamics of the genome. This book summarizes current knowledge and working hypotheses about the frequencies and mechanisms of mitochondrial, plastid, nuclear and viral recombination and the inactivation of repeated genes in plants. Despite rapid developments in the field, it is often not possible to provide final answers. Thus, it is an additional task of this book to define the open questions and future challenges. The book is addressed to scientists working on plant biology and recombination, to newcomers in the field and to advanced biology students.

The book presents updated information on the cryopreservation of semen, embryos, germ cells and ovarian follicles of neotropical fish from South America. The chapters address the importance of developing germplasm banks of South American fish, both for commercial production and for conservation of ichthyofauna. This book has been designed mainly to provide a historical review of the 40 years of reproductive cryobiology research on South American fish species. The work is aimed at students, researchers and technicians involved in the areas related to the book's theme. The editors invite the readers to delve into dense technical knowledge, developed by renowned researchers.

Germ cells have a unique and critical role as the conduit for hereditary information. The issue of male germline mutagenesis and the effects on developmental defects in the next generation has become increasingly high profile in recent years. Understanding the mechanisms by which the germline is induced and maintained is one of the effective ways to treat infertility and cancer. Male-mediated Developmental Toxicity discusses these issues and provides analysis of the fundamental mechanisms of mutations covering both clinical and experimental aspects. It helps clarify the data explaining how genotoxicity involves multiple modes of action and highlights novel models and assays being used to assess germ cell genotoxicity. With a clear focus on the various mechanisms that could impact human health, this book is for postgraduate students and researchers in reproductive and developmental toxicology as well as those with an interest in the fields of genetically inherited diseases, developmental biology and, potentially, those with a more clinical background.

Recent developments of experimental techniques in cellular and molecular biology have made it possible to understand the molecular biology of male gametogenesis in greater detail. This book focuses on the description of specialized proteins, which are dominantly and/or specifically expressed in germ cells and localized in spermatozoa. There is an urgent need to classify proteins of spermatogenic cells with a view of their functions, and their applications in the regulation of fertility and in understanding infertility. The understanding of structural properties of male germ cell specific proteins can offer vulnerable points for targeted intervention in testis without generalized effects on stages of spermatogenesis. Besides targeted action in male germ cells, sperm specific proteins and polypeptides may also offer potential application in the development of a contraceptive vaccine.

Methods in Cell Biology, Volume 158, the latest release in this series, highlights new advances in the field, with this release covering How to orient cells in micro-cavities for high resolution imaging of cytokinesis and lumen formation, A body-on-a-chip (BOC) system for studying gut-liver interaction, Manipulating cultured mammalian cells for mitosis research, Live-cell FLIM-FRET using a commercially available system, A comparative analysis of methods to measure kinetochore-microtubule attachment stability, A workflow for visualizing human cancer biopsies using large-format electron microscopy, Isolation of stage-specific germ cells using facs in drosophila germarium, Computational analysis of filament polymerization dynamics in cytoskeletal networks, and more. Provides the authority and expertise of leading contributors from an international board of authors Presents the latest release in the Methods in Cell Biology series Updated release includes the latest information in this area of study

Echinoderms, Volume 150 in the Methods in Cell Biology series, highlights new advances in the field, with this update presenting interesting chapters on procuring animals and culturing of eggs and embryos, cryopreservation of sea urchin gametes, emerging echinoderm models, culturing of sand dollars, cidaroids and heart urchins, culturing echinoderm larvae through metamorphosis, microinjection methods, injection of exogenous messages and protein overexpression, blastomere transplantation, visualization of embryonic polarity, larval immune cell approaches, methods for analysis of sea urchin primordial germ cells, and protocols and best practices for toxicology and pH studies using echinoderms and several new chapters outlining the use of sea urchins in the classroom. Clear, concise protocols provided by experts who have established the echinoderms as a model system Highlights new advances in the field, with this update presenting interesting chapters on echinoderms

The first chapter of Advances in Medicine and Biology. Volume 147 reviews actions on bone longitudinal growth, muscle, kidney, calcium, nitrogen, phosphorus and potassium, body composition, carbohydrate metabolism, insulin, lipids, protein actions, coagulation and fibrinolysis, adipokines, cardiovascular effects, and retina. Next, the authors discuss the values and boundaries of various surgical approaches to achieve interbody fusion, and introduce a novel fusion technique named extraforaminal lumbar interbody fusion. Each indirect decompression procedure for the intervertebral foramen is introduced in detail, and their influence on intervertebral foramen parameters is discussed, including foraminal height and foraminal area. This provides detailed information on the quantitative decompression index, thus proving helpful for surgeons. Following this, prodrugs are examined, having been extensively studied in the field of drug development. Continuous research in developing prodrugs/drug conjugates has resulted in an improvement of the lipophilicy, aqueous solubility, oral bioavailability, chemical stability, prolongation of action, reduced toxicity and site-specific drug delivery of parent drugs. The susceptibility of germline stem cells to genetic damage induced by oxaliplatin and its mechanism of action is also discussed. Germ cells are responsible for the transmission of genetic information from males to their progeny. The authors evaluate parenteral nutrition-associated liver disease and how it encompasses a variety of diseases ranging from steatosis to fibrosis and cirrhosis. A systematic review of the literature is executed to pool data from all individually documented patients to evaluate the safety and efficacy of combined liver and inferior vena cava resection in patients with colorrectal liver metastases involving inferior vena cava. Research in subsequent chapter examines how the development of purkinje cells in the postnatal period in rats is accompanied by significant structural and metabolic changes, this being the basis for their growth, maturation, differentiation and functions. The authors evaluate the in vitro leishmanicidal activity of the Vanillosmopsis arborea essential oil and its major compound𝛼-bisabolol against Leishmania amazonensis in an effort to evaluate its role to treatdiseases caused by bacteria, fungi, and protozoa, such as leishmaniasis. Since there are still only few data available for the understanding of cellular and molecular functions of Neurensin genes in spite of the expected critical roles in human brain function, the authors present studies which will contribute to elucidating the mechanism of brain disorders at the molecular level. The concluding chapter focuses on the pharmacokinetic/pharmacodynamic properties of emtricitabine, dosing recommendations, and monitoring in the oral antiretroviral preexposure prophylaxis population.

Sex Determination, Volume 134, the latest release in the Current Topics in Developmental Biology series, contains current reviews in the field of vertebrate sex determination. It covers molecular pathways of sex determination in genetic and environmental species and encompasses both sex determination of somatic lineages and commitment of germ cells to male or female fate. Chapters in this new release cover, amongst other topics, Mapping the Sox9 Enhancer Elements, Epigenetic Regulation of Sex Determination, Evolution and Management of Sex Chromosomes, Regulation of Germ Cell Sex Identity in Medaka, Control of Sex Determination in Zebrafish, Sexually Dimorphic Germ Cell Identity in Mammals, and more. - Contains reviews written by leading experts in each field - Includes informative figures that illustrate principle points that are useful for teaching - Written in a style that is clear and simple

Echinoderms and prochordates occupy a key position in vertebrate evolution. The genomes of sea urchin share 70% homology with humans. Researches on cell cycle in sea urchin and phagocytosis in asteroids have fetched Nobel Prizes. In this context, this book assumes immense importance. Echinoderms are unique, as their symmetry is bilateral in larvae but pentamerous radial in adults. The latter has eliminated the development of an anterior head and bilateral appendages. Further, the obligate need to face the substratum for locomotion and acquisition of food has eliminated their planktonic and nektonic existence. Egg size, a decisive factor in recruitment, increases with decreasing depths up to 2,000-5,000 m in lecithotrophic asteroids and ophiuroids but remains constant in their planktotrophics. Smaller ( 110 mm) asteroids generate planktotrophic eggs only. Publications on sex ratio of echinoderms indicate the genetic determination of sex at fertilization but those on hybridization, karyotype and ploidy induction do not provide evidence for heterogametism. But the herbivorous echinoids and larvacea with their gonads harboring both germ cells and Nutritive Phagocytes (NPs) have economized the transportation and hormonal costs on gonadal function. Despite the amazing potential just 2 and 3% of echinoderms undergo clonal reproduction and regeneration, respectively. Fission is triggered, when adequate reserve nutrients are accumulated. It is the most prevalent mode of clonal reproduction in holothuroids, asteroids and ophiuroids. However, budding is a more prevalent mode of clonal reproduction in colonial hemichordates and urochordates. In echinoderms, fission and budding eliminate each other. Similarly, autoregulation of early development eliminates clonal reproduction in echinoids and solitary urochordates. In pterobranchs, thaliaceans and ascidians, the repeated and rapid budding leads to colonial formation. Coloniality imposes reductions in species number and body size, generation time and life span, gonad number and fecundity as well as switching from gonochorism to simultaneous hermaphorditism and oviparity to ovoviviparity/viviparity.

This unique compilation focuses on a very curious organ, the ovary. There are still many unknown facts about the origins of ovarian tissue and ovarian cancer, and each chapter describes in detail the latest insights into the ovary from basic to clinical aspects. Expert authors reveal the most recent findings on ovariogenesis and ovarian carcinogenesis by shedding light on stem cell biology for the ovarian surface epithelial cells or primordial germ cells. Readers will greatly increase their understanding of the relevance of the cells that constitute the ovary, which is of vast significance in comprehending the occurrence mechanism of ovarian tissue and ovarian cancer. In this way the book covers a wide range of fields concerned with the ovary. This work benefits not only gynecologists and obstetricians, but also basic researchers in the field of stem cell biology and all clinicians who are involved in the management of fertility preservation or ovarian cancer.

The management of psoriatic arthritis (PsA) is complex and early intervention is needed to prevent or delay the progression of the disease. The severity of PsA and response to medication should guide the proper treatment modality, as per the recent EULAR and GRAPPA recommendations. In this collection, the authors begin by examining conventional treatment options include non-steroidal anti-inflammatory drugs (NSAIDs) and disease modifying anti-rheumatic drugs. Next, the authors examine parasitic nematodes which cause substantial production losses in grazing animals and suffering in humans. Farmers treat animals with anthelmintics, often in an unplanned way. Frequent whole flock and herd treatments have encouraged the development of resistance as all worms in the animals are exposed to anthelmintic. The single largest problem with anthelmintic resistance is persuading farmers to adopt strategies that slow the development and spread of resistance. The authors go on to discuss the role of green fluorescent protein (GFP) in animal diagnostic technologies, molecular tracking techniques using GFP as fusion tags in studying protein–protein interactions and real time monitoring of host pathogen interactions, as reporter tags in animal viral studies, in in-vitro and in-vivo imaging of transgenic animals for genetic screening and in animal marker vaccines and cancer studies. Following this, the authors provide their understanding of pathogenesis in spinal cord injury (SCI), the current therapeutic efforts and their limitations, and the emerging roles of retinoids in neuroprotection and functional recovery in SCI. Retinoids use retinoic acid receptor (RAR) and retinoid X receptor (RXR) in the cells for modulation of expression of genes that eventually provide neuroprotection in SC. Pap smears detect cytologic abnormalities that indicate the possible presence of a pre-malignant lesion. The cytologic suspicion of a high grade lesion presents the risk of hiding a more severe dysplasia, which has a high risk of progression to invasive neoplastic lesion. Thus, the authors propose that adequate treatment and follow-up should be offered, such as cytology repeat, HPV testing, colposcopy, colposcopy-directed biopsy, or excision of the transformation zone. The subsequent chapter deals with the criteria that can be leant upon to prescribe retinoids for the off-label treatment of dermatological diseases. Exemplary clinical cases are illustrated. The author hopes to inspire creative physicians, and revamp classical, time-honored therapeutic methodologies as well. This book also discusses methods to study bacterial heterogeneity and its influence on phenotypic drug resistance include flow cytometry based approaches, RNA sequencing techniques, microfluidic technology time-lapse microscopy and mass spectrometry-based proteomic approaches. These technological advances are powerful tools that enable us to explore and interrogate mechanisms of bacterial heterogeneity in pathogen populations. Lastly, the authors review the effects of how reproductive toxic exposures induce apoptosis of male germ cells by affecting the spermatogenic cells of the developing testis and investigate several possible mechanisms underlying alkylating agent-induced reproductive toxicity. Furthermore, an understanding of how cells cope with DNA damage caused by alkylating agents is valuable in clinical medicine.

This book provides new insights into the universality of biological systems in animal reproduction and development by a comparative study of a variety of mechanisms in animals ranging from basal invertebrates to vertebrates, including mammals.Animals accomplish genetic diversity through meiosis and fertilization, and during embryogenesis animals must produce specialized cell types, including germ cells, in accordance with their individual body plan. This series of phenomena is essential to the continuity of life in the animal kingdom, and animals show various reproductive and developmental strategies.This volume, comprising four parts, reviews animal kingdom diversity, including reproductive strategies and germ cell differentiation mechanisms (Part 1), sex determination and differentiation (Part2), the mechanisms of fertilization (Part 3), and body axis formation (Part 4). Readers will find descriptions of the reproduction or development of 180 species, 13 phyla, 35 classes, 74 orders, 117 families, and 151 genera in this book. Of particular interest is the diversity of molecules and mechanisms used to achieve the same biological purpose in different animals.Undergraduates, graduate students, and professional scientists who want a deeper understanding of animal reproductive and developmental mechanisms will find this book to be of great value.

In Chapter One, Olga Chub, MD, PhD, and Professor Oleksandr V. Bilchenko, MD present a study exploring the occurrence of plasmid-mediated resistance genes in gram-negative uropathogens. Next, Chapter Two by Daniela Baconi, Miriana Stan, and Ana Maria Vlasceanu reviews recent knowledge on hallucinogenic drugs. In Chapter Three, recent advances in ultrasound imaging are presented. Following this, Chapter Four by Jinhua Dong, PhD, and Hiroshi Ueda, PhD provides an overview on the modern applications of open sandwich immunoassay detection systems. Khaled Habas, Martin H. Brinkworth, and Diana Anderson review the impact of nonsteroidal estrogen diethylstilbestrol on genetic reliability of male germ cells in Chapter Five. In Chapter Six, Petr Slama and Chaivat Kittigul discuss the effect of Staphylococcus aureus infections on leukocytes of bovine mammary gland. Continuing, Chapter Seven by Deryk Jones, MD and Angie Botto-van Bemden, PhD expresses the benefits of using the “Sandwich-ACI” procedure on patients with OCD lesions. Chapter Eight by Seiji Kojima, Tomonobu Kusanom and Yoshiyuki Kamio elaborates on biosynthesis and the function of peptidoglycan-linked cadaverine. Afterwards, Letícia Petersen Schmidt Rosito, MD, PhD, Sady Selaimen da Costa, MD, PhD, and Daniela Pernigotti Dall'Igna, MD present research on the pathogenesis of middle ear cholesteatoma to discern potential future treatment methods in Chapter Nine. Finally, Chapter Ten by Natsuko Kakudo, Naoki Morimoto, Takeshi Ogawa, Fangyuan Lai, Masakatsu Hihara, and Kenji Kusumoto examines the in vitro proliferative capacity of adipose-derived stem cells in order to promote the development of culture methodologies.

This book combines the most recent knowledge on the maternal, i.e. oocyte/egg-specific, molecules and processes. The volume covers the most recent advances in a plethora of subjects such as: maternal transfer of immunity, localized RNAs functions and mechanisms of RNA localization, transcriptional repression of maternal messages, maternal inheritance and maternal role of CRISPR/Cas9-based genome editing, chromatin remodeling and epigenetic modifications, maternal function of nucleosomes, maternal mitochondria and energy supply, role of bacterial symbionts and their maternal transmission, acquisition of oocyte polarity and evolution of maternal effect genes, germ plasm and oosome origin and functions, mechanisms of oocyte activation and soma germ cells communication. Currently, no other book on the market combines such a comprehensive list of subjects in one volume. Moreover, the information provided is a cross-section through oocytes from various invertebrate and vertebrate species, which is another unique feature of this book. The readers, therefore, get a completely new and invaluable perspective on all covered subjects.

This book provides everything from basic knowledge to the recent understandings of avian reproductive physiology, covering many unique aspects. It will inspire avian biologists as well as researchers in varied fields and will offer important steps towards better fertilization success in birds.In spite of the recent remarkable developments in modern technology, a comprehensive understanding of the reproductive mechanisms is still far in the future due to the diverse reproductive tactics in vertebrates. Birds have highly refined reproductive strategies and some of those strategies are unique to birds. However, together with ongoing progress of the genome analysis of birds and the crying need for further increase in meat and egg production, research on avian reproduction is now accelerating and becoming more important.With contributions by leading scientists, the book explains avian primordial germ cells; the sex-determining mechanism; reproductive endocrinology and immunology; sperm, egg, and egg coat; sperm–egg interaction; polyspermic fertilization; seasonal reproduction; social triggers; hormonal and behavioral changes; broodiness; oviductal sperm storage; and biotechnology. This book is recommended for all researchers and students who are interested in birds or reproduction.

This book addresses various aspects of testicular autoimmunity. It has long been suspected that testicular autoimmunity could be one of the causes of idiopathic male infertility. However, it is very difficult to estimate the incidence of testicular autoimmunity in men, as most male patients first realize they are infertile when they start trying to conceive a child, and there is a possibility that their testes may already exhibit the end stage of testicular autoimmunity, in which lymphocytic inflammation and immunoglobulin deposition in their testes subsided long ago and only the spermatogenic disorder remains. Therefore, autopsy or biopsy for testicular tissues in men before the end stage of testicular autoimmunity and investigations using testicular autoimmunity model animals are needed to determine the epidemiology of testicular autoimmunity.Accordingly, the book discusses “the immunological fragility of testis” with regard to male infertility, reviewing autopsy data in men and presenting experimental data using murine models of autoimmune orchitis that has been induced by immunizing with viable syngeneic testicular germ cells alone. Testicular autoimmunity in animals is also discussed. In summary, the book provides a wealth of valuable information, not only for researchers who are interested in immunologic male infertility, but also for clinical professionals who treat these patients at hospitals.

This book presents the current state of knowledge on the origin and differentiation of cell lines involved in the development of the vertebrate male and female gonads with particular emphasis on the mouse. It also discusses the processes leading to the testis- and ovary-specific structures and functions.The individual chapters review the origin and differentiation of the somatic cells of the genital ridges; the formation and migration of primordial germ cells in mouse and man; the gonadal supporting cell lineage and mammalian sex determination; differentiation of Sertoli and granulosa cells; mesonephric cell migration into the gonads and vascularization; origin and differentiation of androgen-producing cells in the gonads; germ cell commitment to the oogenic versus spermatogenic pathway and the role of retinoic acid; ovarian folliculogenesis; control of oocyte growth and development by intercellular communication within the follicular niche; biology of the Sertoli cell in the fetal, pubertal and adult mammalian testis; mechanisms regulating spermatogonial differentiation; stem cells in mammalian gonads; the role of microRNAs in cell differentiation during gonad development; human sex development and its disorders; as well as methods for the study of gonadal development.

The evolutionist Ernst Mayr considered August Weismann “one of the great biologists of all time.” Yet the man who formulated the germ plasm theory—that inheritance is transmitted solely through the nuclei of the egg and sperm cells—has not received an in-depth historical examination. August Weismann reintroduces readers to a towering figure in the life sciences. In this first full-length biography, Frederick Churchill situates Weismann in the swirling intellectual currents of his era and demonstrates how his work paved the way for the modern synthesis of genetics and evolution in the twentieth century.In 1859 Darwin's tantalizing new idea stirred up a great deal of activity and turmoil in the scientific world, to a large extent because the underlying biological mechanisms of evolution through natural selection had not yet been worked out. Weismann's achievement was to unite natural history, embryology, and cell biology under the capacious dome of evolutionary theory. In his major work on the germ plasm (1892), which established the material basis of heredity in the “germ cells,” Weismann delivered a crushing blow to Lamarck's concept of the inheritance of acquired traits.In this deeply researched biography, Churchill explains the development of Weismann's pioneering work based on cytology and embryology and opens up an expanded history of biology from 1859 to 1914. August Weismann is sure to become the definitive account of an extraordinary life and career.