The author describes in his unique style the anatomical variants of the brain and skull. This atlas is a continuation of his last work on "Neuronavigation and Neuroanatomy". Most anatomical reference volumes show a large number of common and rare variations. This atlas concentrates on well known and little known variants which are especially important for the clinicians, in particular the neurosurgeons and the radiologists. The variants have been grouped after areas of trepanation. The author presents also a number of so far unknown variants gathered from his personal theoretical and clinical experience of 50 years. Exact knowledge of anatomical variations which the surgeon may encounter helps to plan operations and to avoid unexpected complications. Variants of no clinical relevance, even rather common ones, have not been included.

The preceding volumes of Cell and Muscle Motility have focused on various aspects of motile systems in both muscle and non muscle cells. These essays have been critical reviews on topics of current interest and, hopefully, have provided a base from which future investigations may develop. During the past decade, however, much attention in the fields of biochemistry and cell biology has focused on motile systems in non muscle cells. Our current under- standing of the three-dimensional organization of the cytoplasm involve three major fibrous proteins which are collectively known as the cytoskeletal system. These polymorphic cytoskeletal proteins are microtubules (25-nm diameter), microfilaments (6-nm diameter), and intermediate filaments (lO-nm diame- ter). Microtubules consist of tubulin and several well-characterized micro- tubule associated proteins (MAPs) including MAP , MAP , tau, and others. l 2 Microfilaments consist of actin and associate with actin-binding proteins in- cluding a-actinin, filamin, myosin, tropomyosin, vinculin, and others. Inter- mediate filaments (lO-nm filaments) consist of at least five different tissue- specific classes, including desmin or skeletin (muscle), prekeratin (epithelial), vimentin (mesenchymal), neurofilament (nerve), and glial acidic fibrillary protein (astrocytes). These major fibrous proteins apparently interact with each other as well as other cytoplasmic components and appear to be inti- mately associated with such biological processes as cell shape changes, growth, motility, secretion, cell division, and uptake of materials from the exterior of the cell.

Ever since television became practical in the early 1950s, closed-circuit television (CCTV) in conjunction with the light microscope has provided large screen display, raised image contrast, and made the images formed by ultraviolet and infrared rays visible. With the introduction of large-scale integrated circuits in the last decade, TV equipment has improved by leaps and bounds, as has its application in microscopy. With modem CCTV, sometimes with the help of digital computers, we can distill the image from a scene that appears to be nothing but noise; capture fluorescence too dim to be seen; visualize structures far below the limit of resolution; crispen images hidden in fog; measure, count, and sort objects; and record in time-lapsed and high-speed sequences through the light microscope without great difficulty. In fact, video is becoming indispensable for harnessing the fullest capacity of the light microscope, a capacity that itself is much greater than could have been envisioned just a few years ago. The time seemed ripe then to review the basics of video, and of microscopy, and to examine how the two could best be combined to accomplish these tasks. The Marine Biological Laboratory short courses on Analytical and Quantitative Light Microscopy in Biology, Medicine, and the Materials Sciences, and the many inquiries I received on video microscopy, supported such an effort, and Kirk Jensen of Plenum Press persuaded me of its worth.

Boost your exam chances with this brand new workbook and revision guide, designed to improve and assess your knowledge of anatomy and physiology theory and how it applies to practical treatments. - Prepare for success with comprehensive coverage of anatomy and physiology by body system - Coach yourself with a variety of workbook activities for self-study - Test yourself with multiple-choice and exam-style questions - Combine your workbook with Helen McGuinness's bestselling Anatomy and Physiology textbook (sold separately) for the strongest anatomy and physiology support in your Beauty Therapy studies

The Ninth Annual Pezcoller Symposium entitled "The Biology of Tumors" was held in Rovereto, Italy, June 4-7, 1997. It focused on the genetic mechanisms underlying het erogeneity of tumor cell populations and tumor cell differentiation, on interactions be tween tumor cells and cells of host defenses, and the mechanisms of angiogenesis. With presentations at the cutting edge of progress and stimulating discussions, this symposium addressed issues related to phenomena concerned with cell regulation and cell interactions as determined by activated genes through the appropriate and timely media tion of gene products. Important methodologies that would allow scientists to measure dif ferentially genes and gene products and thus validate many of the mechanisms of control currently proposed were considered, as were the molecular basis of tumor recognition by the immune system, interactions between cells and molecular mechanisms of cell regula tion as they are affected by or implemented through these interactions. The molecular and cellular mechanisms of tumor vascularization were also discussed. It was recognized that angiogenesis provides a potential site of therapeutic intervention and this makes it even more important to understand the mechanisms underlying it. We wish to thank the participants in the symposium for their substantial contribu tions and their participation in the spirited discussions that followed. We would also like to thank Drs."

The genus Pseudomonas represents a large group of medically and envi ronmentally important bacteria. Interest in these bacteria is reflected in the extensive number of publications devoted to original research, re views, and books on this subject. In this volume selected areas of Pseu domonas research are presented in depth by persons who have been active in their fields over many years. The extensive reviews presented are an effort to provide a balanced perspective in a number of areas not readily available in the current literature. In the style of the previous Biotechnology Handbooks most of these topics have not been reviewed at all, and several are also presented from a new direction. For example, in addition to structural and compositional aspects, the chapter on lipids provides shifts in lipid parameters that result from environmental changes. This information will be invaluable to a cross section of Pseu domonas researchers in pathogenesis and bioremediation. The chapters presented include basic aspects of plasmid biology and carbohydrate metabolism and regulation. A major emphasis is placed on the Pseudomonas aeruginosa cell surface. Chapters cover lipo polysaccharide, capsular polysaccharide and alginate, the outer mem brane, transport systems, and the flagellum. Uptake of iron is also neces sarily an important portion of the chapter on iron metabolism.

Complex physiopathological relationships have been proven to exist between two of the body's most vital organs; the brain and the heart. In Cell Cycle Regulation and Differentiation in Cardiovascular and Neural Systems Antonio Giordano, Umberto Galderisi and a panel of the most respected authorities in their field offer an in-depth analysis of the differentiation process in two systems that have profound relationships with one another. The text looks at several aspects of the cardiovascular and nervous systems from a new point of view, describing the differences and similarities in their differentiation pathways with an emphasis on the role of cell cycle regulation and cell differentiation. Topics discussed include neurogenesis in the central nervous system, neural stem cells, and the basic-helix-loop-helix transcription factors in neural differentiation. Ground-breaking and authoritative, Cell Cycle Regulation and Differentiation in Cardiovascular and Neural Systems is a must have for all researchers in cardiovascular medicine and neuroscience and will prompt the scientific community to perceive cell cycle regulation and differentiation under a novel and more comprehensive light.

The last few years have witnessed an explosion of both interest and knowledge about apoptosis, the process by which a cell actively commits suicide. The number of publications on the topic has increased from nothing in the early 1980s to more than 10,000 papers annually today. It is now well recognized that apoptosis is essential in many aspects of normal development and is required for maintaining tissue homeostasis. The idea that life requires death seems somewhat paradoxical, but cell suicide is essential for an animal to survive. For example, without selective destruction of "non-self" T cells, an animal would lack immunity. Similarly, meaningful neural connections in the brain are whittled from a mass of cells. Further, developmental cell remodeling during tissue maturation involves programmed cell death as the major mechanism for functional and structural safe transition of undifferentiated cells to more specialized counterparts. Apoptosis research, with roots in biochemistry, developmental and cell biology, genetics, and immunology, embraces this long-ignored natural law. Failure to properly regulate apoptosis can have catastrophic consequences. Cancer and many diseases (AIDS, Alzheimer's disease, Parkinson's disease, heart attack, stroke, etc. ) are thought to arise from deregulation of apoptosis. As apoptosis emerges as a key biological regulatory mechanism, it has become harder and harder to keep up with new developments in this field.

This book represents the invited presentations and some of the posters presented at the conference entitled "In Vitro-In Vivo Relationship (IVIVR) Workshop" held in Sep tember, 1996. The workshop was organized by the IVIVR Cooperative Working Group which has drawn together scientists from a number of organizations and institutions, both academic and industrial. In addition to Elan Corporation, which is a drug delivery com pany specializing in the development of ER (Extended Release) dosage forms, the IVIVR Cooperative Working Group consists of collaborators from the University of Maryland at Baltimore, University College Dublin, Trinity College Dublin, and the University of Not tingham in the UK. The principal collaborators are: Dr. Jackie Butler, Elan Corporation Prof. Owen Corrigan, Trinity College Dublin Dr. lain Cumming, Elan Corporation Dr. John Devane, Elan Corporation Dr. Adrian Dunne, University College Dublin Dr. Stuart Madden, Elan Corporation Dr. Colin Melia, University of Nottingham Mr. Tom O'Hara, Elan Corporation Dr. Deborah Piscitelli, University of Maryland at Baltimore Dr. Araz Raoof, Elan Corporation Mr. Paul Stark, Elan Corporation Dr. David Young, University of Maryland at Baltimore The purpose of the workshop was to discuss new concepts and methods in the devel opment of in vitro-in vivo relationships for ER products. The original idea went back ap proximately 15 months prior to the workshop itself. For some time, the principal collaborators had been working together on various aspects of dosage form development.

These proceedings contain selected contributions from the participants to the Fourth International Symposium on Dendritic cells that was held in Venice (Lido) Italy, from Oc tober 5 to 10, 1996. The symposium was attended by more than 500 scientists coming from 24 different countries. Studies on dendritic cells (DC) have been greatly hampered by the difficulties in preparing sufficient cell numbers and in a reasonable pure form. At this meeting it has been shown that large quantities of DC can be generated from precursors in both mice and humans, and this possibility has enormously encouraged studies aimed to characterize DC physiology and DC-specific genes, and to employ DC therapeutically as adjuvants for im munization. The possibility of generating large numbers of autologous DC that can be used in the manipulation of the immune response against cancer and infectious diseases has tremendously boosted dendritic cell research and the role of DC in a number of medi cal areas has been heatedly discussed."

Key features: * Provides a clear explanation for many of the pain generators in low back pain and illuminate this perplexing and ubiquitous problem. * Addresses a gap in the existing literature, as "non-specific" or mechanical lumbosacral spine pain accounts for by far most chronic spinal pain sufferers' complaints for clinicians dealing with spinal pain syndromes like general medical practitioners, and spinal specialists in various fields such as sports medicine. * Illustrates anatomical structures that can be injured and thus become responsible for causing mechanical lumbosacral spine pain, frequently, such injuries cannot be detected on sophisticated imaging such as MRI.

lar aging, to which this model contributes, has grown. Apart from reports on work in this almost "classical" diploid cell system, the symposium presents studies using different biological systems with results that have been rewarding as information is obtained on patterns of change that are common to more than one experimental system. Indeed, in recent years much more has been learned about the fate of all different types of intermitotic and postmitotic cells in situ. The symposium has also presented contributions dealing, not directly with aging but with early ontogeny; such information on early developmental changes should certainly shed light on some of the mechanisms involved in aging. We are cognizant of the fact that environmental influences resulting from the complexities of modern civilization may have results that only occur much later, and profoundly affect the lifespan of the organism. There remain, of course, many unanswered questions. Whether there is "physiological" as opposed to "pathological" aging; whether "old" cultures living in unchanged, although not exhausted, medium, are degenerating, not aging; what is involved when "old" fragment cultures regenerate after excision by filling the wound with "young" cells; why some tumor cells in vivo as well as in vitro die while others live; all are questions eserving of our attention.

Advances in Cell Biology has been initiated as a continuing, multi-volume series to report on the progress of a wide spectrum of problems of cell structure and cell function. Jn arranging these volumes individual contributors are asked not only to review the major new information, but especially to present the state of a given problem or area by discussing the current central issues, speculations, concepts, hypotheses, and technical problems. We intend, in addition, that these volumes will not be concerned with comprehensive reviews of the recent literature but will consist rather of presentations of an interpretive and integrative nature, based on selection of major research advances. It is our aim that these volumes should provide the means whereby cell biologists may keep themselves reasonably well informed about the current progress in research areas in cell biology in which they are not immediately or directly involved themselves. The articles, nevertheless, are expected to bring into focus the experimental objectives of the specialists in a given research area. D. M.P. L. G. E.M. vii Contents Contributors v Preface vii 1 1. The Regulation of DNA Synthesis in Eukaryotes James Douglas Watson 2. D.RNA Containing Ribonucleoprotein Particles and Messenger RNA Transport 47 G. P. Georgiev and 0. P. Samarina Recent Developments in the Synchronization of 3. Tetrahymena Cell Cycle 111 Eric Zeuthen 153 4. Repetitious DNA Christopher Bostock 5. Mitosis 225 R. Bruce Nicklas Specific Enzyme Production in Eukaryotic Cells 299 6."

Unique features of the present work include: Only authorized English translation of the original Spanish text, adhering as much as possible to the letter, with correction of the obvious errors already predicted by Cajal in his Preface. Added facts appearing in the French version, with correction of old as well as new errors, the latter probably due to inaccuracies in translating into French some nuances of the Spanish language. Uniform of nomenclature according to contemporary scientific English. Annotations on Cajal s changing concepts over time, the elucidation of certain structures that do not have present day equivalents, and explanations of the many symbols appearing in illustrations but not mentioned in the corresponding original legends. Most illustrations are reproductions of Cajal s original art work, still extant at the Cajal Museum in Madrid, with cross references to figure numbers of the Spanish and French versions. Citations are given by author and year in the text, with an alphabetical list at the end of the volume, completed and corrected for accuracy against original publications. Taxonomy glossary of species appearing in the text, with present scientific names, and their colloquial English counterparts."

The discovery of the human T cell leukemia virus type I in the late 1970s heralded a new era in retrovirology. For the first time, it was demonstrated that a retrovirus could play a role in the development of a human disease, in this case adult T cell leukemia (ATL). Several years later, the acquired immunodeficiency syndrome (AIDS) epidemic began, and it was dem- strated that a retrovirus, originally designated the human T cell lymp- tropic virus type 3, was the causal agent of this syndrome. This virus, later named the human immunodeficiency virus type 1 (HIV-1), has since been extensively studied in terms of its pathogenesis as well as its ability to elicit immune responses. In that time, a tremendous amount of information has been obtained about the virus. Although recent drug regimens have been useful in significantly lowering viral loads and perhaps maintaining an asymptomatic state among individuals infected with HIV-1, an established "cure" for AIDS eludes us. In addition, the effective drug therapies are very expensive, and are not available to infected people in the third world, where greater than 90% of new infections occur. Furthermore, the development of viral resistance against the drug therapies is an additional concern. Despite extensive study, no effective vaccine has been developed. One of the problems in developing an effective vaccine against HIV-1 is the ability of the virus, particularly in the immunogenic envelop glycoprotein, to undergo amino acid hypervariability.

The day it rained in Wepion ..... . The NATO Course on Regulation of Function and Growth of Eukaryo tic Cells by Intracellular Cyclic Nucleotides was organized in Wepion (Belgium) from September 23 to October 1, 1974, by L. Birn baumer (Chicago), B.L. Brown (London), R.W. Butcher (Worcester), J.E. Dumont (Brussels), M. Paiva (Brussels) and G. Van den Berghe (Louvain), under the benevolent and most efficient aegis of Dr. T. Kester (NATO, Brussels). The formula of the Course was inspired by the Gordon Con ference with its combination of a pleasant, friendly and easygoing atmosphere together with a solid and critical scientific diet offered in the morning and evening, the afternoon being free. For these reasons, the meeting was located in a pleasant motel in beautiful surroundings by the side of the Meuse river, in the country, but close to the town of Narnur. Everything, absolutely everything, from swimming to tennis, to horse riding, was available to make the afternoons agreeable and to facilitate social contacts."

Anatomy, to be sure, is the essential foundation of clinical practice, but it is much more than that. First and foremost, anatomy is a biological science. There is order and logic to the organization of the human body and the arrangement of its parts. And, as all sciences, anatomy offers challenge and discovery. Concepts in Anatomy is not a textbook, but more of a brief handbook that is selective rather than encyclopedic in scope, conception rather than particular in its approach. It stresses general principles, so as to minimize rote learning, and it provides order and direction to the study of gross anatomy. Anatomy is inherently complicated and confusing; this volume helps you make sense of it in a way that also aims to inspire its study. Richly illustrated with original drawings, Concepts in Anatomy is a valuable resource for anyone currently studying or teaching the subject, or as a reference for advanced researchers.

This monograph, Senescence; Dominant or Recessive In Somatic Cell Crosses? represents the second annual workshop to promote theory and concept development in aging research. These workshops are part of a resource to bank cultured cells of special interest to aging research that was established at the Institute for Medical Research in Camden. New Jersey. by the National Institute on Aging in 1974. The underlying theme of the workshops is the use of cultured cells in a variety of somatic cell genetic systems designed to define mechanisms of in vitra cellular scen escence and the possible insights that this may provide to the problems of in viva aging. The concept also includes bringing together workers from a variety of disciplines to stimulate new and innovative thoughts and work in the area. The current work shop focuses on the relative role of nucleus and cytoplasm on determining the in vitra lifespan of human diploid cells as well as the relative influence of old and young cells when combined within a single cell structure. The techniques and procedures discussed should make significant contributions to understanding in vitra senescence and may lead to the mapping of an area or areas of the genome linked to senescence as is being accomplished with viral transformation of normal cells. Warren W. Nichols Donald G. Murphy ~i Contents Theoretic Mechanisms of in vitpo Senescence 1 F. MaPott Sinex . . . . . . . . . . . . Senescence in Ce1l Cu1ture: An Accumu1ation of Errors or Terminal Differentiation? 13 Vincent J. GPistofaZo . . . . . . . . . . . . . .

This monograph analyses all aspects related to the etiopathogenesis, pathomorphology, diagnosis and treatment of lumbar disc herniation. It includes 24 chapters, over 500 illustrations, partly in colour, and 2800 bibliographic entries, going from the historical to the most recent ones. Five chapters are dedicated to biological and pathomorphologic aspects both of lumbar disc herniation and the conditions most often associated with herniation. The etiopathogenesis is analysed in the light of the most significant and recent studies. Five chapters deal with the clinical presentation and diagnostic tests in an extremely wide and detailed way. Large space is reserved to conservative management. The chapters on invasive treatments and on the results and complications of surgery define the advantages and limitations of the old and new percutaneous or surgical treatments. Two chapters are dedicated to surgical management of patients with spinal conditions associated with herniation, and two other deal with the surgical failure. This monograph is aimed at satisfying the requirements of both experts and young doctors. Some chapters are of particular interest to the spine specialist, whilst others are useful to the novice to acquire a general knowledge of the subject.

This volume contains refereed manuscripts prepared from presentations made at the 2ih annual meeting of the International Society on Oxygen Transport to Tissue (ISOTT). The meeting was held in Hanover, NH, USA, at Dartmouth Medical School, the 3rd oldest medical school in the USA. ISOTT attempts to produce high quality pUblications on cutting edge topics relating to oxygen in living systerns. The goal is to allow contributors to contribute original data, as with a main-stream journal article, but also to voice individual opinions and ideas in a more relaxed scientific forum. The meeting brought together an international group of scientists who share a common interest in the measurement and role of oxygen in living systems. The organizers of ISOTT99 made a special effort to bring together people from industry, medicine, and basic sciences in order to improve the links in the chain of discovery through to application. As a result, this volume contains publications on a range of subjects. There are contributions from companies on modifiers of oxygen carrying capacity (allosteric modifiers of hemoglobin and infusible oxygen carriers or blood substitutes); technical reports on oxygen measurement devices including advances in near-infrared spectroscopy and imaging, oxygen electrodes, magnetic resonance spectroscopy and imaging, and fluorescence based measurements. There are medically related sections on modifying and measuring tumor oxygenation in order to improve therapy, assessment and interpretation of oxygenation in the central nervous system, and general issues relating oxygen to pathological conditions.

This volume contains papers presented at the Fourth International Altschul Sympo- sium, held June 27-29, 1996, at the University of Saskatchewan in Saskatoon, Saskatche- wan, Canada. The Altschul Symposia Series are held in memory of Rudolf Altschul, a graduate of the University of Prague and a pioneer in the fields of vascular and nervous system biology. Dr. Altschul was head of the Department of Anatomy at the University of Saskatchewan from 1955 to 1963. The Altschul Symposia are made possible by an endow- ment left by Anni Altschul, Dr. Altschul's wife, and by other contributions given by the sponsors listed at the end of this Preface. The objective of the Fourth Altschul Symposium, entitled Cell Biologv and Pathol- ogv of Myelin: Evolving Biological Concepts and Therapeutic Approaches, was to facili- tate the transfer of ideas on the biology and pathology of myelin from the research laboratory to the clinic by providing a forum for discussing the evolving biological con- cepts regarding myelin function in health and disease.

The aim of this Atlas is to present the three-dimensional arrangement of the liver structures, which should be familiar to those who diagnose and treat diseases of the liver, particularly in an era when the methods of diagnostic imaging and surgical treatment are becoming increasingly sophisticated. For this purpose a series of corrosive preparations of the blood vessels and bile ducts of the liver was made and photographed. In addition to the normal situations, many frequent and rare variations are shown. The Atlas also shows some blood vessels that have not been adequately described or are not well-known in the reference literature, but are nevertheless of great importance in performing segmental liver resections.This Atlas takes a fresh approach to the subject. The method used allows the size, three-dimensional arrangement and structure of the blood vessels and bile ducts of the liver to be preserved. The majority of photographs were taken from the direction from which surgeons see the liver during an operation. This, together with the schematic presentations complementing most of the photographs, gives a further instructional value to the work. With colour photographs and explanatory text, the Atlas forms a basic guide to orientation inside the liver parenchyma, to understanding and diagnosing certain pathological processes and to planning surgcial procedures.

This translation from Russian into English of the monograph Hematopoi- etic and Lymphoid Tissue in Culture by E. A. Luriya provides us for the first time with a comprehensive review of the massive amount of work carried out in the USSR in this important area of biological research. Historically, the pioneering tissue culture studies of Maksimov, Popov, Chasovnikov, and their colleagues working in Russia in the early part of this century provided much of the impetus for subsequent studies on lymphopoiesis and hematopoiesis in vitro and much of the basic information used subsequently to achieve immune responses in vitro and to develop the methodology for cloning hematopoietic stem cells. Particularly welcome in this translation is the addition of the Appendix, in which Drs. Luriya and Fridenshtein describe in some detail the methodology that has been developed in their laboratories for the study of a variety of cell types in cell and tissue culture. For many of us, this description provides information that had previously not been accessible to us: porosity of millipore fIlters in relation to growth properties; colony-forming cell adhesiveness; pro- liferation kinetics of stromal cells; differential effectiveness of various media used for culture of liver cells; details of washing procedures for fIlter substrates used in culture.

During the last decade, rapid progress has been made in the area of microbial immu- nity. New conceptual frameworks have emerged with regard to the processing and presen- tation of peptides and nonpeptide antigens from microbes, especially bacteria, to T cells in the context of classical MHC class I and nonconventional MHC I molecules. Experimen- tal models have been instrumental in defining some of these pathways for generating pro- tective immune responses against microbes, which form the basis for the design of new vaccines. New evidence has stressed the importance of innate immunity in microbial in- fections. The concept of dichotomy within T helper cells has revealed the role of these cell types in resistance and susceptibility to microbial-mediated pathology. These latest devel- opments in microbial immunity are discussed in this volume. Natural killer cell development is known to be regulated by the presence of MHC class I antigens. Receptors for MHC class I molecules on NK cells have been discovered. Interaction of these receptors with their specific ligands leads to inhibition of cytotoxicity. Vinay Kumar and colleagues review NK cell differentiation and ontogeny, and functions of NK cells in experimental animals. Lewis Lanier discusses the role of a newly discov- ered molecule, DAP 12, in KIR and other receptor-mediated signal transduction in NK cells. Eric Long describes the regulation of immune response by inhibitory receptors.

Recent advances in our understanding of the fundamental role of bioactive lipids in normal and abnormal physiology was the theme of the XVlth International Spring Sympo- 6-9, 1996 at the George Washington University School sium on Health Sciences held on May of Medicine in Washington, D.C. Over 250 participants shared their latest findings on fundamental mechanisms in lipid metabolism, transport, and signal transduction. Most of the papers presented at the plenary sessions have been collected in this volume, which is divided into seven parts. The focus of Part I is on the new roles that fatty acids and esters play in cellular function. These activities include regulation of gene expression, control of eicosanoid-me- diated responses, and intracellular calcium sequestration. Most biological effects of fatty acids, esters, and phospholipids are transmitted via the interaction of these lipid molecules with specific lipid binding proteins. The chapters in Part II detail the involvement of these in the transport of fatty acids, fatty acyl CoA esters, and phospholipids, and in the proteins modulation of the fatty acid-induced activation of the peroxisome proliferator-activated receptors. The study of arachidonic acid metabolism continues to be the subject of intense interest and research. A number of studies in Part III deal with the substantial differences between the constitutive prostaglandin H synthase isozyme (PGHS-l or COX-I) and the inducible form PGHS-2 (COX-2) regarding compartmentation, control, and expression.