Effects of N2, O2′-dibutyril cyclic GMP on the nucleoside phosphotransferase activity of the retina of the chick embryos

Summary In the retina of the chick embryo, 2 different forms of nucleoside phosphotransferase take part in the phosphorylation of thymidine. One is an unstable form with higher molecular weight. The other with lower m. wt is a stable form. This paper shows that N², O²-dibutyril cyclic GMP causes a marked decrement of the activity of the unstable nucleoside phosphotransferase.     

Identification of ϱ-antigenic determinants on the surface,of mouse T-lymphocytes

Summary A monospecific antiserum has been prepared in rabbits against purified -antigen, a 100,000 mol.wt glycoprotein found on the surface of mouse L-cells. This antiserum has been employed to demonstrate the presence of -antigenic determinants selectively on the surface of mouse T-, but not B-lymphocytes.We thank Drs A. Christopher and R. Hunt for advice during the course of these studies. This work was supported by grants from the U.S. Public Health Service and the American Cancer Society.     

Dopamine-β-hydroxylase,adrenaline, noradrenaline and dopamine in the venous blood of adrenal gland of man: A comparison with levels in the periphery of the circulation

Summary In 10 human subjects plasma dopamine--hydroxylase activity was found in the adrenal vein blood to be as high as in the periphery of the circulation. Adrenaline concentration in the adrenal vein blood was in the mean 170 times, noradrenaline concentration 11 times and dopamine concentration little higher than levels in the periphery.This study was supported by the Deutsche Forschungsgemeinschaft.     

In vitro inactivation of the neurotoxic action of β-bungarotoxin by the marine natural product,manoalide

Summary The irreversible neurotoxic action of -bungarotoxin (-BuTx) can be prevented by preincubation of the toxin with manoalide, a non-steroidal anti-inflammatory agent. Manoalide was also found to inactivate purified phospholipase A₂ and thus prevent hydrolysis of phosphatidylcholine. PLA₂ is a component found in several neurotoxic venoms and is also a rate limiting enzyme important in phospholipid metabolism and prostaglandin synthesis in man.This work is a result of research sponsored in part by NOAA-Department of Commerce under Sea Grant No. NA80AA-D-00120 and the California State Resources Agency R/MP-21. The US Government is authorized to produce and distribute reprints for governmental purposes. A preliminary report of aspects of this work appeared in Fedn Proc.42 (1983) 374. We also acknowledge the technical assistance of Dan Rohrer. Dr George Taborski's advice and assistance during the course of this work is gratefully acknowledged.J. C. de Freitas is a post-doctoral fellow supported by Fundacao de Amparo à Pesquisa do Estado de São Paulo (81/0263-9) and Conselho Nacional de Desenvolvimento Cientifico e Tecnológico (201.171/82), Brazil.     

β-Methyl carboline,a benzodiazepine inverse agonist,attenuates the effect of triazolam on the circadian rhythm of locomotor activity

Summary The benzodiazepine triazolam, the benzodiazepine inverse agonist, -methyl carboline (-CCM) or both, were administered to adult male hamsters under conditions of constant light. When given alone, triazolam induced phase advances in the circadian activity rhythm of about 90 min, while -CCM when given alone, had no effect on phase of the activity rhythm. However, when triazolam and -CCM were given at the same time, the magnitude of the phase advances induced by triazolam were attenuated to about 30 min. These data, in conjunction with previous results, provide pharmacological evidence for a GABAergic system involved in the regulation of a central circadian pacemaker.     

Comparison of the effects of lithium,β-phenylethylamine and tyrosine onXenopus embryos

Résumé On a étudié les effets du lithium, de la -phényléthylamine et de la tyrosine sur le développement embryonnaire deXenopus laevis. La tyrosine n'a pas d'effet, mais le lithium ou la -phényléthylamine ont végétalisé les embryons s'ils ont été exposés avant le stade blastula.     

Good, bad or offal? The evaluation of raw pancreas therapy and the rhetoric of control in the therapeutic trial, 1925

In 1925 a debate erupted in the correspondence columns of the British Medical Journal concerning the effectiveness of eating raw pancreas as a treatment for diabetes. Enthusiasts were predominantly general practitioners (GPs), who claimed success for the therapy on the basis of their clinical impressions. Their detractors were laboratory-oriented 'biochemist-physicians,' who considered that their own experiments demonstrated that raw pancreas therapy was ineffective. The biochemist-physicians consistently dismissed the GPs' observations as inadequately 'controlled'. They did not define the meaning of 'control' in this context, although it clearly did not have the term's present-day meaning of a trial employing an untreated comparison group of patients. Rather, the physician-biochemists' 'properly controlled' experiments involved careful regulation of their patients' diet and other environmental factors, and evaluation of the therapy's success through biochemical, rather than just clinical, criteria. However, my analysis suggests that these factors alone are inadequate to account for the biochemist-physicians' dismissal of the GPs' work as 'uncontrolled'. I suggest that the biochemist-physicians were deliberately exploiting the powerful rhetorical connotations of the term 'control'. Ultimately, they implied that only a trial which they themselves had conducted could be deemed 'adequately controlled'.     

The in vivo expression of the globin genes of theβ cistron in γ-,δ-, andδβ-thalassemia heterozygotes

There is considerable evidence suggesting that the switch from to and chain production after birth is due, in part, to silencing of the genes by stage-specific factors which bind to their promoters and to the competition from the adult ( and ) genes for a common enhancer element located in the locus control region. As a consequence one can expect that the increased Hb F production in adults with hereditary persistence of fetal hemoglobin or -thalassemia is directed mainly by -globin genes in cis to the deletion(s) responsible for these conditions. Here we review data on heterozygotes with -, -, or -thalassemia, who also had an^AT mutation, in cis or in trans, which was used as a marker of gene expression. The results show that a deletion affecting adult genes favors the expression of genes in cis, while the deletion of a single gene does not affect the expression of the gene in cis but leads to a faster switch postnatally.     

Bolzano,Cauchy and the “new analysis” of the early nineteenth century

Summary In this paper I discuss the development of mathematical analysis during the second and third decades of the nineteenth century; and in particular I assert that the well-known correspondence of new ideas to be found in the writings of Bolzano and Cauchy is not a coincidence, but that Cauchy had read one particular paper of Bolzano and drew on its results without acknowledgement. The reasons for this conjecture involve not only the texts in question but also the state of development of mathematical analysis itself, Cauchy both as personality and as mathematician, and the rivalries which were prevalent in Paris at that time.     

The development of the Laplace transform, 1737–1937

This paper, the first of two, follows the development of theLaplace Transform from its earliest beginnings withEuler, usually dated at 1737, to the year 1880, whenSpitzer was its major, if himself relatively minor, protagonist. The coverage aims at completeness, and shows the state which the technique reached in the hands of its greatest exponent to that time,Petzval. A sequel will trace the development of the modern theory from its beginnings withPoincaré to its present form, due toDoetsch.     

Crossing the Olentangy River: The Figure of the Earth and the Military-Industrial-Academic-Complex, 1947–1972

This paper explores the history of a unique assemblage of researchers in the geodetic and allied sciences organised at Ohio State University (OSU) in 1947 at the beginning of the Cold War. From about 1950 to 1970, the OSU geodetic sciences group was the most significant group of geodetic researchers in the world. Funded almost entirely by military and intelligence agencies, they pioneered the technologies, organised the research initiatives, ordered the data sets, and trained the generation of geodesists who eventually created the Cold War Figure of the Earth to both prosecute and prevent global nuclear war. They devised elaborate mechanisms to pursue in secrecy and isolation research that had hitherto been performed collaboratively and globally. They invented methods to maintain professional associations and protocols, both to distribute—and disguise—the fruits of their geodetic research. In accomplishing this, their work also undermined the basic hypothesis of isostasy that had been foundational to geodesy for the previous century.Fundamental progress in the geosciences and military and intelligence directives were inextricably linked during the Cold War, although the extent of their convergence has been masked by the security protocols organised to disguise it. With the declassification of key programmes underway, it is now both possible and necessary to substantially revise the history of Cold War-era geosciences and their associated technologies.     

Identification of a plant growth inhibiting iridoid lactone fromDuroia hirsuta,the allelopathic tree of the ‘Devil's Garden’

Bioactivity-directed fractionation of a root extract ofDuroia hirsuta (Rubiaceae), a toxic and potentially allelopathic understory tree from the western Amazon, has led to the isolation of the tetracyclic iridoid lactone, plumericin (1). Bioassays showing plumericin strongly inhibited lettuce radicle elongation at a concentration (IC₅₀) of 35.8 m/ml (123 M). The isolation of a highly potent inhibitor of plant growth fromDuroia hirsuta supports the hypothesis that the lack of vegetation surrounding this tree is the result of allelopathy.     

(Z,E)-α-farnesene,main constitutent of the hypertrophied Dufour's gland of the major workers ofPheidole pallidula (Formicidae)

Summary In the European dimorphic ant,Pheidole pallidula, the Dufour's gland of the major workers is hypertrophied and secretes nearly pure (Z, E)--farnesene. This compound is also present in the Dufour's gland of the minor workers but constitutes only around 10% of the volatiles. Chemical polymorphism inP. pallidula is different from that already reported for species ofPheidole from the New World.Aspirante au Fonds National de la Recherche Scientifique.Maître de recherches du Fonds National de la Recherche Scientifique.     

A fungus pigment of novel type,and the nature of fungus ‘lignin’

Zusammenfassung In den Früchten des höheren PilzesPolyporus hispidus bildet sichin situ ein ligninähnlicher Stoff durch Oxidation-Polymerisation von Phenolen des Phenylpropantyps, hauptsächlich Hispidin (I), dessen Struktur als Enollacton der 3,4-Dihydroxycinnamoylacetessigsäure erkannt wurde.     

Rôle of the nucleus in the maintenance of the protein level in the algaAcetabularia mediterranea

Riassunto Sono state studiate le variazioni del rapporto tra l'N proteico e non proteico in segmenti rigeneranti, nucleati ed anucleati, diAcetabul. medit. I risultati ottenuti hanno dimostrato che il predetto rapporto aumenta in entrambi i segmenti il primo giorno dopo l'operazione. Nei giorni seguenti esso diminuisce in entrambi i segmenti, ma più sensibilmente in quelli anucleati, nei quali va al di sotto del valore medio delle alghe normali già dopo il 3°–4° giorno.     

The ‘Spitzenkörper’, centre of the reducing power in the growing hyphal apices of two septomycetous fungi

Summary Redox dyes, such as methylene blue and neutral red, are stably reduced to their leucobase in the Spritzenkörper of the growing hyphal tips ofNeurospora crassa andMonilia fructigena.We acknowledge the support of the Fonds National Suisse de la Recherche Scientifique and thank both Mrs Ton-That for her electron micrograph and Miss E. Herz for her technical help.     

Can the binding of GABA,glycine and β-alanine to synaptic receptors be determined in the presence of a physiological concentration of Na+?

Summary Bicuculline- and strychnine-sensitive components of the binding of GABA, glycine and -alanine, which can be demonstrated in the presence of a physiological concentration of Na⁺, might be related to synaptic receptors.     

α-Endosulfine, a new entity in the control of insulin secretion

ATP-dependent potassium (K_ATP) channels occupy a key position in the control of insulin release from the pancreatic β cell since they couple cell polarity to metabolism. These channels close when more ATP is produced via glucose metabolism. They are also controlled by sulfonylureas, a class of drugs used in type 2 diabetic patients for triggering insulin secretion from β cells that have lost part of their sensitivity to glucose. We have demonstrated the existence of endogenous counterparts to sulfonylureas which we have called ‘endosulfines.’ In this review, we describe the discovery, isolation, cloning, and biological features of the high-molecular-mass form, α-endosulfine, and discuss its possible role in the physiology of the β cell as well as in pathology. Received 1 February 1999; received after revision 26 March 1999; accepted 26 March 1999     

Influence of the structure of theN-terminal extremity ofα-MSH on the melanophore stimulating activity of this hormone

Zusammenfassung Drei strukturelle Analoge des-MSH wurden synthetisiert und auf ihre Melanophoren-stimulierende Wirksamkeit untersucht. Für das Auftreten einer ausgeprägten biologischen Aktivität scheint die Anwesenheit einerN-Acetyl-Gruppe an dem Aminoende der Peptidkette wichtiger zu sein als das Vorhandensein der zwei ersten amino-endständigen Aminosäurereste der-MSH-Kette.