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Books > Medicine > Pre-clinical medicine: basic sciences > Physiology > General
More than 70 years have elapsed since U. S. von Euler and I. H.
Gaddum dis- covered an unidentified depressor substance in the
brain and gut. The effects of the powdery extracts were marked as
'P' on the kymograph tracings, and the nondescript name of
'substance P' still carries the breath of this adventurous period.
In the 1960s, substance P returned in another disguise, staging as
a hypothalamic peptide that causes copious salivary secretion (see
chapter by F. Lembeck and I. Donnerer). This time, though, the
mysterious substance was tracked down by S. E. Leeman and her
collaborators as an undecapeptide, after it had eluded its
identification for some 40 years. Substance P turned out to be the
mammalian counterpart of a family of peptides which had been
extracted from amphibian and nonvertebrate species and which had
been given the name 'tachykinins' by V. Erspamer. Soon novel
members of this peptide family were discovered, and in mammals
substance P was joined by neurokinin A and neu- rokinin B. The
presence of tachykinins in frog skin as well as in venoms and
toxins of microbes and arachnids raises the possibility that these
peptides re- present an old system of biological weapons that have
been transformed to a particular messenger system in mammals.
Electric currents and electromagnetic fields have been applied to
biological systems, particularly humans, with both therapeutic and
pathological results. This text discusses biological responses to
electric currents and electromagnetic fields, including medical
applications and shock hazards. It covers fundamental physical and
engineering principles of responses to short-term electrical
exposure and emphasises human reactions, although animal responses
are considered as well, and the treatment covers reactions from the
just-detectable to the clearly detrimental. An important new
chapter discusses standards for human exposure to electromagnetic
fields and electric current and demonstrates how these standards
have been developed using the principles treated in earlier
chapters.
In recent years, we have witnessed a rapid expansion of our
knowledge regarding the role of the endothelium in the control of
vascular tone (and organ perfusion) in health and disease.
Physiology, pharmacology, and molecular biology have uncovered a
wealth of information on structure and function of this heretofore
largely neglected "organ". Clinical medicine is now called upon to
define the clinical significance of these observa tions that imply
the mechanisms of blood coagulation, e.g., the interaction of throm
bocytes with the endothelium, vasomotor control, and specifically,
the regulation of smooth muscle tone with consequences for vascular
resistance and conductance and organ blood flow. Finally,
metabolism of lipids with the everlasting problem of athero
sclerosis is an important aspect. In a second step, implications
regarding the improvement of current therapeutic con cepts, as well
as the development of new modalities of pharmacotherapy will have
to be discussed. The topic addressed by the 1990 Gargellen
Conference: Endothelial Mechanisms of Vasomotor Control, clearly is
of interest for both basic scientists and clinicians. It has been
the aim of the organizers, the Society for Cooperation in Medical
Science (SCMS) with this and the previous symposia to foster and
support both basic science and clinical research. Research in
medicine today shows two major directions of development: on the
one hand, increasing involvement of the basic sciences and their
methodology. On the other hand, statistical validation of concepts
and therapeutic strategies in large scale population-and
multicenter-studies.
"What we call the beginning is often the end, and to make an end is
to make a beginning. The end is where we start from." T. S. ELIOT,
"Geroniton" The discovery of endothelin-l was both an end and a
beginning. It is an end because this discovery has started a
plethora of investigations as to endothe1in's sites of production,
mode of action, it's normal and abnormal physiological role and its
involvement in a variety of pathological conditions ranging from
renal failure to myocardial infarction, cardiac hypertrophy,
hyperten sion, cyclosporine induced toxicity, mental depression,
renal failure, stress related illness, and even stroke and sudden
death. It is a beginning because no one can foresee where the
investigations will ultimately lead, or how they will end. The
discovery of the endothelins was a very recent event and soon
specialist books will start to appear dealing in detail with
different aspects of their chemistry, physiological role and
pathological importance. The present book is intended to act as a
guide and primer for those who are becoming intrigued by the many
endothelin related articles which are now appearing in the journals
but who as yet have not had the time or opportunity to be caught up
in the web of enthusiasm and excitement which is motivating those
more directly involved in the field of research.
Stress, high blood pressure, smoking, pollution, fast foods,
overweight, excessive travelling, surgery, less movement are common
features in our modern life. These features are risky for blood
clotting disorders. According to WHO, over 29% of the total
mortalities worldwide are due to thrombosis. By the year, 2020
cardiovascular diseases (CVDs) may cause an estimated 25 million
deaths per year, thus antithrombotic therapy is of great
interest.
The available thrombolytic agents such as urokinase are highly
expensive, antigenic, quite unspecific, pyretogenic and
hemorrhagenic. Therefore, the production of fibrinolysing enzymes,
which rapidly dissolute thrombi within the vascular tree, without
the detriments by microorganisms, as described in this book, is the
desirable aim of today s research. "
The scientific literature has expanded dramatically in recent
years, making entry into the structure of any given area extremely
difficult; concurrent with this explosion more people are required
to become acquainted with information outside their main line of
expertise. For this reason there is a need for review articles
which give an overall review of circumscribed areas. This volume
reviews the subject of respiratory control mechanisms; the authors
of each chapter are active research workers engaged in the area
covered by their chapter. The first four chapters are concerned
with the basic physiological mechanisms which sense changes in the
respiratory system, in the standard physiology textbook parlance
chemical and neural sensory receptors. The peripheral arterial
chemoreceptors sense changes in arterial oxygen tension, carbon
dioxide and pH. The first chapter describes the basic responses in
the organ produced by changes in blood chemistry. Later chapters
discuss changes in activity produced by exercise, chronic hypoxia
and the possible role of the chemoreceptors in initiation of
respiration in the new-born. In Chapter 1, a section considers the
action of drugs on the peripheral chemoreceptors, and finally there
is a discussion of the possible mechanisms whereby the organs sense
changes in blood chemistry. This pattern is followed in subsequent
chapters wherever possible; first a discussion of the basic
physiological properties, followed by any clinical application and
dis cussion of the mechanism whereby the receptor might operate.
The remaining chapters are of a more applied nature.
and made insignificant in practice, by selecting for study simple
kinds of ex periences which are devoid of emotional content and
which can be tested for reliability. A simple somatosensory ''raw
feel" fulfills these characteristics (see papers nos. 2,5). In any
case, if we fail to find ways to use introspective reports in
convincingly acceptable studies we would give up the ability to
investigate the relation between conscious experience and neural
activity, something warned against by William James (Krech, 1969).
Another factor in the dearth of direct experimental studies is, of
course, the comparative inaccessibility of the human brain for such
purposes. Meaningful investigations of the issue in question
requires simultaneous study of brain events and introspective
reports of experiences in an awake, cooperative human subject.
Analysis by neuropsychologists of pathological lesions in the brain
and the related disturbances of conscious functions have
contributed much to mapping the pos sible representations of these
functions. The non-invasive recording of electrical activity with
electrodes on the scalp, starting from Berger's initial EEG record
ings in 1929, has contributed much to the problems of states of
consciousness and to various cognitive features associated with
sensory inputs, but not as much to the specific issue of conscious
experience."
"Provides analytical chemists and biomedical scientists with an
excellent summary of progress...This is a book that can be
recommended to all analytical scientists interested in
fluorimetry." (Analytical Chimica Acta) "This is a useful overview
and gives the nonspecialist a feeling for the advantages and
limitations of the methods. Overall this book is a worthwhile read
and a good source of references." (TRAC)
The book is divided into chapters on new methods, new appli-
cations, fluorescence immunoassays, fluorometric analysis and
fluorescence spectroscopy in biomedical sciences. Specific topics
are fluorescence spectroscopy using synchrotron radiation,
picosecond fluorescence spectroscopy, fluorescence microscopy,
fluorescence scattering by synthetic polymers, fluorescence
immunoassays, fluorescence for environmental monitoring,
fluorescence in flow injection analysis, hydro-geological studies,
fluorescence of proteins, lipids and membranes, cell fluorescence,
calcium transients.
Though it is a pleasure to write a short foreword to this
collection of excellent scientific papers covering a range of
biological topics, the rather depressing feature is the small
number of papers. All-electronic publishing is developing and your
Editors do have great faith in it. One problem for potential
authors has been the reluctance of the abstracting journals to pay
any attention to electronic journals - perhaps Springer should make
a rapid move in this area and start the first all-electronic
journal abstracting this type of literature. However, even the
paper citation journals are starting to pay attention to the
medium. The particular advantages of all-electronic publishing are
beginning to emerge more clearly and it is clear that publishing
video material is a unique advantage of our format. Several papers
took advantage of this - for example those by Riehle and others on
cell behaviour in tunnels, by Bereiter-Hahn and Voss on zonation in
the plasmalemma and by Pavlikova, Zicha, Chaloupkova and Vesely on
cell motility of tumour cells. These papers made essential and
extensive use of video material, publishing some material of great
originality. The work on cell pola rity and calcium ions in Fucus
embryos by Brownlee, Manison and Anning used animation to present
their results in an especially clear way. The facility of use of
animation is another special advantage of our type of publication
that should be more widely used."
This section will consider the structure and function of muscle
receptors, as well as the central nervous system mechanisms with
which they are concerned. In volume I of this Handbook, receptor
mechanisms are discussed in detail. Also, the crustacean stretch
receptor and the frog muscle spindle have been considered. The
present section will be concerned with vertebrate muscle receptors
with an emphasis on mammals. Muscle receptors provide interesting
examples of specialized mechanorecep tors. The muscle spindle is a
striking case of a receptor which is regulated in its function by
the central nervous system in efferent neurons. Muscle receptors
have long been known to playa crucial role in the reflex regulation
of movement. In recent years it has become apparent that these
receptors are also important in sensory phenomena such as the
perception of position and movement. St. Louis, July 1974 c.c. HUNT
Contents Chapter I The Morphology of Muscle Receptors. By D.
BARKER. With 99 Figures . . . . . . . . . . . . . . . .. 1 Chapter
II The Physiology of Muscle Receptors. By C.C. HUNT. With 21
Figures . . . . . . . . . . . . . . . . . 191 Chapter III Central
Actions of Impulses in Muscle Afferent Fibres. By A. K. McINTYRE.
With 8 Figures 235 Author Index 289 Subject Index 299 List of
Contributors BARKER, David Department of Zoology, University of
Durham, Science Laboratories, South Road, Durham DH1 3LE, Great
Britain HUNT, Carlton C. Department of Physiology and Biophysics,
Washington University, School of Medicine, 660 South Euclid Avenue,
St. Louis, Mo. 63110, USA McINTYRE, A. K."
In 1976, when Springer-Verlag commissioned Professors Giebisch,
Tosteson, and Ussing to edit what was destined to become a
monumental five-volume Handbuch (" Membrane Transport in Biology",
1978 [Vols I, II, III] and 1979 [Vols IV A, B]), the subject of
transepithelial secretion was still in its infancy. Not
surprisingly, therefore, their Handbuch concentrated mainly on
trans- epithelial absorption, although substantial chapters dealing
with some secre- viz. "Ion Transport Across the Choroid Plexus"
tory organs were included, (by E. M. Wright), "Sweat Glands" (by J.
H. Thaysen), "Lacrimal Gland" (by J. H. Thaysen) and "Transport
Across Insect Excretory Epithelia" (by J. P. H. Maddrell) in Volume
III and "Transport in Salivary and Salt Glands" (by J. A. Young and
E. W. Van Lennep), "Gastric Secretion" (by T. E. Machen and J. G.
Forte), "Transport Processes in the Exocrine Pan- creas" (by I.
Schulz and K. J. Ullrich), and "Transport of Ions in Liver Cells"
(by M. Claret) in Volume IVB. The publication in 1977 of the
seminal paper of Silva and his colleagues on the mechanism of
secretion of salt and water in the salt excreting gland of the
dogfish (American Journal of Physiology 233, F298-F306, 1977)
provided physiologists with their first real insight into the
mechanisms underlying transepithelial fluid secretion, however,
and, in the ensuing years, interest in the topic has exploded as is
evidenced by the numerous international symposia on exocrine
secretion held since that date.
Since the endothelium plays such an important role in the
pathophysiology of the circulatory system, the readers attention is
directed here towards the possible involvement of these
polypeptides in the aetiology of ischaemic heart disease,
cerebrovascular accidents, hypertension, atherosclerosis and renal
failure.
For a comprehensive understanding of human physiology - from
molecules to systems -turn to the latest edition of Medical
Physiology. This updated textbook is known for its unparalleled
depth of information, equipping students with a solid foundation
for a future in medicine and healthcare, and providing clinical and
research professionals with a reliable go-to reference. Complex
concepts are presented in a clear, concise, and logically organized
format to further facilitate understanding and retention. Clear,
didactic illustrations visually present processes in a clear,
concise manner that is easy to understand. Intuitive organization
and consistent writing style facilitates navigation and
comprehension. Takes a strong molecular and cellular approach that
relates these concepts to human physiology and disease. Student
Consult eBook version included with purchase. This enhanced eBook
experience includes access -- on a variety of devices -- to the
complete text with thorough hyperlinking, images, 10 animations,
and copious linkout notes prepared by the Editors. An increased
number of clinical correlations provides a better understanding of
the practical applications of physiology in medicine. Highlights
new breakthroughs in molecular and cellular processes, such as the
role of epigenetics, necroptosis, and ion channels in physiologic
processes, to give insights into human development, growth, and
disease. Several new authors offer fresh perspectives in many key
sections of the text, and meticulous editing makes this
multi-authored resource read with one unified voice. Your purchase
entitles you to access the web site until the next edition is
published, or until the current edition is no longer offered for
sale by Elsevier, whichever occurs first. If the next edition is
published less than one year after your purchase, you will be
entitled to online access for one year from your date of purchase.
Elsevier reserves the right to offer a suitable replacement product
(such as a downloadable or CD-ROM-based electronic version) should
online access to the web site be discontinued.
Skeletal muscle consumes significant amounts of oxygen, and its
oxygen flux increases significantly under conditions of exercise
and muscle contraction. This makes the muscle vulnerable to
oxidative stress since concomitantly with the increase of oxygen
flow there is an increase of free oxygen radicals which are a
byproduct of muscle respiration. A number of studies in the last
decade have documented the involvement of free oxygen radicals in
exercising muscles. The consequences of muscle oxidative stress
have resulted mainly in increased muscle protein oxidation,
elevation of lipid peroxidation, and depletion of muscle
antioxidants. The mechanisms of this oxidative stress are under
extensive investigation in laboratories around the world and are
topics of the chapters in this volume. This book is intended for
professionals who are interested in muscle function, physiology,
pathophysiology and well-being, such as therapists, trainers and
medical professionals as well as for researchers in the field of
muscle physiology.
Despite major efforts by the scientific community over the years,
our understanding of the pathogenesis or the mechanisms of injury
of multiple sclerosis is still limited. Consequently, the current
strategies for treatment and management of patients are limited in
their efficacy. The mechanisms of tissue protection and repair are
probably even less understood. One reason for these limitations is
the enormous complexity of the disease and every facet of its
pathogenesis, the mechanisms of tissue injury, the diagnostic
procedures and finally the efficacy of treatments and their side
effects. The aim of this book is to review the most recent advances
made in this highly complex field.
A new presentation of physiological regulatory mechanisms and
therapeutic applications is given in this book. It represents a
collection of the most up-to-date information in cholecystokinin
(CCK) research, especially focusing on the development and
characterization of CCK antagonists. The book contains chapters on
the synthesis, biochemical and pharmacological characterization of
potent and selective CCK antagonists as well as physiological
applications of these compounds. The last section of the book is
devoted to the involvement of CCK in pathological states and
potential clinical applications of CCK antagonists.
One of the prerequisites for survival is the ability of cells to
maintain their volume. Thus, during the course of evolution cells
have "learned" a variety of strategies to achieve volume
homeostasis. This volume regulatory machinery involves regulation
of both, cellular metabolism and cellular transport and is
exploited by hormones and transmitters to regulate
cellularfunction. This book to illustrates the complex interplay of
cell volume regulatory mechanisms and cellular function in a
variety of tissues. However, our knowledge is still far from being
conclusive, and the present collection of reviews is thought to
foster further experimental efforts to unravel the role of cell
volume in the integrated function of cells.
The authors, all accomplished and world-renowned experts in their
topic areas, have provided controversial and up-to-date accounts of
the current status of research in calcium and bone metabolism by
reviewing major areas of basic science which have an impact on the
understanding of bone diseases and related disorders.
Idiopathic cardiomyopathy has been categorized for over 10 years by
the World Health Organization as dilated, hypertrophic, or
restrictive. These categories have somewhat vague boundaries;
however, idiopathic dilated cardiomyopathy (IDC) finds its general
definition from unexplained four-chamber dilatation, prominent
systolic dysfunction with depressed ejection fraction, a marked
increase in total myocardial mass without wall thickening, myocyte
hypertrophy and nuclear polyploidy, rarity of frank myocardial
scars, but increased interstitial connective tissue and myocyte
atrophy, all in the setting of anatomically normal heart valves and
coronary arteries. Mural thrombi within cardiac chambers and
atrioventricular valve regurgitation are common secondary con-
comitants. Myocardial inflammation is rare, but immunological
abnormalities have been suggested. Ultrastructural features in-
clude increased mitochondrial numbers, lipid deposits, and myo-
fibrillar loss. Progressive pump failure with or without rhythm
disturbances typically leads to ever-intensified medical therapies,
and ultimately to transplantation or early death. The need for
better understanding of IDC is represented by incidence rates
varying from 5 to 8/100000 population across several populations,
10 000-20000 IDC deaths annually in the United States, and the
generally increasing prevalence of the disease. More than 50% of
heart transplant recipients have IDC as their primary myocardial
disease. The half-life of patient sur- vival without
transplantation is generally less than 5 years. Treat- ment with
antiarrhythmics, calcium channel blockers, ~-adrenergic blockers,
and angiotensin-converting enzyme inhibitors is being evaluated in
clinical trials, but the role of such treatments in the
pathobiology of progressive disease is unclear.
Sympathetic afferent fibers originate from a visceral organ, course
in the thoracolumbar rami communicantes, have cell bodies located
in dorsal root ganglia, and terminate in the gray matter of the
spinal cord. Sympathetic afferent fibers from the heart transmit
information about noxious stimuli associated with myocardial
ischemia, i. e. angina pectoris. Previous reviews have described
the characteristics of cardiovascular sympathetic afferent fibers
(Bishop et al. 1983; Malliani 1982). This review summarizes that
work and focuses on the neural mechanisms underlying the
complexities of angina pectoris. In order to understand anginal
pain, cells forming the classical pain pathway, the spinothalamic
tract (STn, were chosen for study. These cells were chosen to
address questions about anginal pain because they transmit
nociceptive informa of pain. Antidromic tion to brain regions that
are involved in the perception activation of STT cells provided a
means of identifying cells involved with trans mission of
nociceptive information in anesthetized animals. Other ascending
pathways may also transmit nociceptive information, but many
studies show that the STT plays an important role. Visceral pain is
commonly referred to overlying somatic structures. The pain of
angina pectoris can be sensed over a wide area of the thorax: in
the retrosternal, precordial anterior thoracic, and anterior
cervical regions of the chest; in the left or sometimes even the
right shoulder, arm, wrist, or hand; or in the jaw and teeth
(Harrison and Reeves 1968)."
Modern Methods of Plant Analysis When the handbook Modern Methods
of Plant Analysis was first introduced in 1954 the considerations
were: 1. the dependence of scientific progress in biology on the
improvement of existing and the introduction of new methods; 2. the
difficulty in finding many new analytical methods in specialized
journals which are normally not accessible to experimental plant
biologists; 3. the fact that in the methods sections of papers the
description of methods is frequently so compact, or even sometimes
so incomplete that it is difficult to reproduce experiments. These
considerations still stand today. The series was highly successful,
seven volumes appearing between 1956 and 1964. Since there is still
today a demand for the old series, the publisher has decided to
resume publication of Modern Methods of Plant Analysis. It is hoped
that the New Series will be just as acceptable to those working in
plant sciences and related fields as the early volumes undoubtedly
were. It is difficult to single out the major reasons for success
of any publication, but we believe that the methods published in
the first series were up-to-date at the time and presented in a way
that made description, as applied to plant material, complete in
itself with little need to consult other publications. Contributing
authors have attempted to follow these guidelines in this New
Series of volumes.
The most comprehensive and conceptual one-volume treatment of this
field available and the first to emphasize the cellular and
molecular aspects of gut peptide biology. Authored by an array of
internationally distinguished scientists, it deals with issues of
peptide localization and biosynthesis in gastrointestinal cells,
mechanisms of peptide release and inactivation and the nature of
peptide receptors. The breadth and readability make it an
invaluable reference source for scientists in all disciplines
interested in any aspect of brain-gut peptides.
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