Tannin und Adrenalin

Summary Tannic acid in concentrations which of themselves have no action potentiates and prolongs the action of adrenaline on the isolated rabbit intestine (inhibitory effect) and on the isolated non-pregnant rabbit uterus (excitatory effect). The adrenaline-pressor effect in the decapitated cat and, in the same species, its stimulant action on the nictitating membrane (either denervated or normal) may also be potentiated by tannic acid. Since the oxidation of adrenalinein vitro is inhibited by tannic acid, it seems that this—in addition to a possible increase of permeability—is mainly responsible for the potentiation of adrenaline.     

Prevention of experimental liver metastases by D-galactose

Summary The metastasis of malignant tumors from a primary site to near and distant secondary sites is probably the most important event in the pathogenesis of cancer and it accounts for most cancer deaths¹. Whereas advances in the treatment of primary cancer have led to increased patient survival, metastatic cancers are still the most difficult group of diseases to treat successfully². As organ-characteristic lectins play an important role in the organ manifestation of metastatic islets^3,4, it might be possible (e.g. during surgical operations on malignant tumors) to block those organ-characteristic lectins with the appropriate receptor-bearing glycoconjugates in order to inhibit the metastatic spread. Recent experiments have demonstrated that neuraminidase treatment of tumor cells (mouse sarcoma-1) alters in vivo (Balb/c-mice) the organotropic distribution of metastases; instead of being found exclusively in the lung, they are found both in lung and liver. However, pre-injection and regular application of D-galactose — the same holds for arabinogalactan^5,6,13 — prevents the settling of metastases in the liver but does not influence the metastatic process to the lung, whereas mannan — as a galactose-free control substance — does not alter the initial pattern of metastasis to lung and liver.     

Origin and development of neuroepithelial bodies in fetal rabbit lungs

Summary Light-microscope studies concerning the embryological development of fetal rabbit lungs revealed the occurrence of argyrophilic neuroepithelial bodies in an early gestational stage (i.e. already in the glandular period and from the 18th day onwards). Their morphological characteristics and further differentiation towards birth are detailed.Supported by a grant from the Nationaal Fonds voor Wetenschappelijk Onderzoek — Fonds voor Geneeskundig Wetenschappelijk Onderzoek (Belgium). We thank E. Swinnen. H. Van den Bosch and M.R. Van hamme for technical, G. Pison for photographical and L. Lauwers for secretarial assistance.     

Cholinesterase reactivators — Contribution to the study of their metabolic effects

Summary Cholinesterase reactivators — trimedoxim, methoxim and obidoxim — injected in the dose of 20 mg/kg s.c., increase muscle glycogen concentration in normal, but not in adrenalectomized rats. This effect may be in connection with simoultaneously found rise of serum corticosteron level. Trimedoxim decreases adrenaline, methoxim and obidoxim noradrenaline concentration in adrenals.     

Veränderungen in der Mitochondrienfraktion der Rattenleber nach Total- und Leberfeldbestrahlung (1000 r)

Summary A study was made of the influence of local (liver field) and total irradiation (1,000 rl) on the enzymatic activity of isolated liver mitochondria from adult rats. While the succinodehydrogenase activity remains unaltered, the oxydation of pyruvate — as well as the structural stability of the mitochondria — are found to be reduced, entailing a decrease in the oxydative phosphorylation. These variations remain the same even after total or local irradiation.     

The evolution of BioBike: Community adaptation of a biocomputing platform

Programming languages are, at the same time, instruments and communicative artifacts that evolve rapidly through use. In this paper I describe an online computing platform called BioBike. BioBike is a trading zone where biologists and programmers collaborate in the development of an extended vocabulary and functionality for computational genomics. In the course of this work they develop interactional expertise with one another’s domains. The extended BioBike vocabulary operates on two planes: as a working programming language, and as a pidgin in the conversation between the biologists and engineers. The flexibility that permits this community to dynamically extend BioBike’s working vocabulary—to form new pidgins—makes BioBike unique among computational tools, which usually are not themselves adapted through the collaborations that they facilitate. Thus BioBike is itself a crucial feature—which it is tempting to refer to as a participant—in the developing interaction.     

What Do We Measure When We Measure Aggression?

Biological research on aggression is increasingly consulted for possible answers to the social problems of crime and violence. This paper reviews some contrasting approaches to the biological understanding of behavior—behavioral genetic, social-environmental, physiological, developmental—as a prelude to arguing that approaches to aggression are beset by vagueness and imprecision in their definitions and disunity in their measurement strategies. This vagueness and disunity undermines attempts to compare and evaluate the different approaches empirically. Nevertheless, the definitions reveal commitments to particular metaphysical views concerning behavior. Alternative understandings of aggression suggest even different research approaches than those most commonly found in the literature.     

Vergleichende Elektronenmikroskopie reiner DNS und der DNS des Bakteriennukleoids

Summary The behaviour of pure isolated DNA towards the conditions of fixation and dehydration—prior to ultrathin sectioning—has been studied and compared with the behaviour of the DNA-plasm of the bacterial nucleus. It is found that those conditions which produce coarse coagulation of the free DNA also produce electron opaque bodies of variable aspect inside the bacterial nucleus. The coagulation figures obtained in both situations are very similar. This is a further direct evidence in favour of the view that the bacterial nucleus is an assembly of fine DNA-containing fibrilla in a highly hydrated plasma.     

Zur Phagozytose strahlengeschädigter Lymphocyten des Thymus

Summary Part of the lymphocytes of the thymus were phagocytized by epithelial and mesenchymal reticular cells in rats after X-ray irradiation of the whole body. The intracellular decomposition is obviously brought about by the two cellular forms in a different way. Pearl-string-like structures — probably nucleoproteids — were found in the cytoplasma in the case of the epithelial cells. On the other hand, numerous cytoplasma inclusions of different size, which are evidently reduced lymphocytic nuclei, could be observed in the case of the mesenchymal cells.     

Structures and molecules involved in generation and regulation of biological rhythms in vertebrates and invertebrates

Melatonin from the retina and the pineal gland functions in neuroendocrine hierarchies. Photoreceptors — eyes and extraretinal — detect light. Oscillators — pineal and suprachiasmatic nuclei — act as pacemakers. Driven neuroendocrine rhythms carry temporal hormone signals throughout the body. Light controls melatonin: light sets the phase of the melatonin rhythm and determines the duration of melatonin synthesis. By these means, circadian rhythms (e.g. in locomotor activity and body temperature) and seasonal rhythms (e.g. in reproduction) are controlled.     

Hensen's node — The ’Organizer’ of the amniote embryo

Conclusion If the hundred years of study on theHensen's node — i.e. on gastrulation and early determination of the embryos of amniote vertebrates — teach anything, they teach in the first place how limited and fragmentary our knowledge is about one of the most central problems of the whole developmental biology. We know that the events in early amniote development — or early avian development, on which our data and ideas are nearly all based — in many ways resemble those in early Amphibian development, which is only slightly better understood, but we also know that direct extrapolations from anamniotes to amniotes cannot be made without proper reservations and without studying the amniote embryos themselves. And we have practically no idea of what is really going on in the cells of the blastoderm when they move, invaginate, induce or are induced, interact, become determined and begin their differentiation. We know that at the stages of gastrulation, the node, and indeed the whole blastoderm, is in a very labile state and can be regulated in many ways to produce a harmonious whole — or a monster — although we only understand very poorly the modes of this regulation. The progress made during the decades, and particularly in recent years, shows, however, that useful information is accumulating to produce a coherent picture, and there is no reason to be pessimistic.Dedicated to ProfessorEtienne Wolff on the occasion of his retirement.     

Immunochemical identification of vitellogenin in the serum of the newtTriturus cristatus

Summary The hematic yolk precursor — vitellogenin — has been identified immunochemically in the serum of estrogenized females of the newtTriturus cristatus by employing an antiserum prepared against yolk proteins.     

Age and evolution of bacteria

Summary Age and evolution of bacteria can be estimated, including facts and hypotheses belonging to morphology, biochemistry, paleontology, ecology and pathogenicity. The corresponding dates are summarized in the following.About 3.5×10⁹ years: Origin of heterotrophic eobiontes.—About 3.0×10⁹ years: The increasing lack of prebiogenic substances is due to the evolution of the respiratory pathway, that is due to the evolution of the photoautotrophy and now released O₂ is due to the evolution of strictly aerobic cells. There is, simultaneously, a transition of spheres to long forms, development of an amoebalike motility, the evolution of spirochetes and the substitution of cholesterol for cardiolipin in the more evolved cells (i.e. strictly aerobic cells etc.).—About 2.0×1.0×10⁹ years: Evolution of the eucyte by symbiosis of a great, primitive, anaerobic, cholesterol-containing cell with a little, strictly aerobic, cardiolipin-containing cell, with a spirochete and in some extent also with photoautotrophic cell.—About 1.0×10⁹ years (maximum: 1.8–1.5×10⁹ years, minimum: 7×10⁸ years): Evolution of metazoa and begin of cell differentiation.—About 2.0–1.0×10⁹ years: Evolution of the bacterial murein sacculus and then development of flagella mediated motility.—About 6×10⁸ years (maximum:1.0×10⁹ years, minimum: 4.5×10⁸ years): Evolution of the gram-negative cell wall.—About 4.0×10⁸ years: Evolution of the gram-positive cell wall.—About 5.0×10⁸ years: Gram-negative, strictly anaerobic bacteria become the first enteric bacteria in coelenterates. About 4.0×10⁸ years: gram-negative, microaerophilic bacteria become Enterobacteriaceae in vertebrates in addition to the strictly anaerobic organisms.—About 3.0–2.0×10⁸ years: Consolidation of the Salmonella in reptiles.—About 2.0–1.5×10⁸ years: Consolidation of Escherichia and other coliform species in mammals.—About 10⁶ years: Evolution of typically human pathogenic organisms, transmitted in homogeneous-homonomous infection ways, i.e. N. gonorrhoeae, S. typhi, T. pallidum, etc.Dedicated to Prof. H. Habs, Bonn, to his 75th anniversary on 11 September 1977.Acknowledgment. I thank Prof. F. Müller, Hamburg, and Prof. P. Sitte, Freiburg i. Br., for stimulating discussions.     

Hochenergiephysik

Summary Short Review of the actual state of High Energy Physics: Cosmic ray research — Accelerators for high energy particles — Instruments for detection of fast particles — Classification of elementary particles.     

Morphological evidence for axonal transport of glycogen in neurons innervating cutaneous receptors inLacerta sicula (Squamata: Reptilia)

Summary Three types of glycogen-containing cutaneous nerve terminals — two of them hitherto unknown — are described. It is shown that the glycogen is synthesized in the perikaryon and transferred to the terminals by means of slow axoplasmic transport.     

Tierexperimentelle Studien über die Alkoholverbrennung

Summary While in dogs intravenously administered alcohol is eliminated as a straight function of time, it was found that the combustion of alcohol, when given intraperitoneally in rats, depends on the concentration at a given time. Since the dog — like man — belongs to a species with a slow alcohol combustion, while the rat (together with the mouse) has the highest metabolic velocity, it is supposed that the supply of alcohol dehydrogenase might determine not only the metabolic velocity as such but also the rhythm of alcohol combustion: when the ADH supply is low, the combustion capacity limit will be reached at low blood alcohol concentrations and the elimination curve will become linear.     

Holism and structuralism in U(1) gauge theory

After decades of neglect philosophers of physics have discovered gauge theories—arguably the paradigm of modern field physics—as a genuine topic for foundational and philosophical research. Incidentally, in the last couple of years interest from the philosophy of physics in structural realism—in the eyes of its proponents the best suited realist position towards modern physics—has also raised. This paper tries to connect both topics and aims to show that structural realism gains further credence from an ontological analysis of gauge theories—in particular U(1) gauge theory. In the first part of the paper the framework of fiber bundle gauge theories is briefly presented and the interpretation of local gauge symmetry will be examined. In the second part, an ontological underdetermination of gauge theories is carved out by considering the various kinds of non-locality involved in such typical effects as the Aharonov–Bohm effect. The analysis shows that the peculiar form of non-separability figuring in gauge theories is a variant of spatiotemporal holism and can be distinguished from quantum theoretic holism. In the last part of the paper the arguments for a gauge theoretic support of structural realism are laid out and discussed.     

Interaction of atropine or methylatropinium with four effects of two cholinergic drugs

Summary In mice, pilocarpine — or oxotremorine — induced decrease in locomotor activity and increase of the reaction time to pain were antagonized by atropine and not by methylatropinium. Identical doses of atropine and methylatropinium suppressed the antagonism of the cholinergics towards reserpine-induced palpebral ptosis. Cholinergics-induced hypothermia was not clearly antagonized by atropine or methylatropinium.     

Photobiochemistry without light

Summary Efficient excited state formation — much higher than that hitherto expected — may occur in organelles and in intact cells. Excited triplet states can be enzymatically generated in high yields by different routes. An example is the oxidation of isobutanal to acetone and formic acid, catalyzed by horseradish peroxidase. Other enzymatic systems that generate triplet carbonyls are linear aliphatic aldehydes when oxidized by peroxidase/O₂, or the indole-3-acetic acid/peroxidase/O₂-reaction. The latter is widespread in plants.This new field — photobiochemistry without light — has led to a growing awareness of the idea that cells may utilize excited states to trigger photochemical processes even in the dark. Such phenomena are of considerable importance, also for the understanding of weak photon emission from biological systems.     

The literature and the science of ‘two cultures’ historiography

This paper discusses the historiography of the ‘two cultures’ controversy. C. P. Snow’s lament about the ‘two cultures’, literary and scientific, has inspired a wide range of comment—much of which begins by citing Snow and his thesis, before going on to discuss very different things. This paper focuses upon one strand of this commentary, the historical analysis of the controversy itself. A ‘historical’ analysis is defined here as one that resists the impulse to enter the argument on behalf of Snow or Leavis, to conceive of their argument in the terms that Snow defined, or to invoke their argument as a precursor to some contemporary issue. Instead, a historical interpretation registers distance between that day and this, takes the controversy itself as its object of study, and explores the tensions and associations that came to be packed into those now familiar terms. As the fiftieth anniversary of Snow’s Rede Lecture nears, this approach—rather than the repetition of clichés about the bridging of cultures—offers both analytical perspective on the controversy and interpretive possibilities for its examination.