Radioprotective effect of reticuloendothelial system blockade in mice

Zusammenfassung Die i.v. Injektion von Kohlepartikeln an Mäusen, 24 h vor einer Bestrahlung mit 600 R, bietet einen bemerkenswerten Strahlenschutz. Die Problematik der biologischen Schutzfunktion durch die Reticulo-histiocytäre Systemblockade wird diskutiert.     

A method for perfusing tissue culture with an in vivo system

Riassunto Il lavoro descrive una modificazione della camera di Rose che permette la perfusione delle culture tramite una membrana semipermeabile.     

Oxytocin analogs effective as noncompetitive inhibitors in uterotonic test

Summary Deamino-1-carba-oxytocin analogs with a chemically reactive group in position 4 were demonstrated to act as noncompetitive oxytocin inhibitors in the assay on isolated rat uterus.     

d-andl-isomers of serine and alanine equally effective as releasers of gastrin

Zusammenfassung l-undl-Isomere von Alanin und Serin sind beide wirksam, von der Antrumschleimhaut aus den Gastrinmechanismus zu aktivieren.

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This work was supported by Veterans Administration research funds and by grants from the US Public Health Service.     

Proteases of Antarctic krill--a new system for effective enzymatic debridement of necrotic ulcerations

The Antarctic krill (Euphausia superba) possesses an "over-dimensioned' digestive system, which is of vital importance for the survival of this euphaucean shrimp in the extreme marine environment. The isolated enzymes contain a well-balanced mixture of both endo- and exopeptidases, assuring fast and complete breakdown of proteinaceous material. These unique properties have now been shown to be extremely valuable for the effective removal of necrotic debris, fibrin or blood crusts in vitro. Therefore the krill enzymes should be considered as an important resource in the future management of necrotic wounds.     

Pyridine as an unmasking reagent for lipoprotein complexes in the nervous system of protein deficient squirrel monkeys

Summary Acid hematin test with pyridine and Sudan black B controls was employed on selected areas of the brains of 115, 140 days fetuses, neonates and adult squirrel monkeys maintained on low and high protein diet. Our histochemical findings indicate that the reduction of phospholipids in the low protein fetuses and neonates is related to myelination, whereas in the adults, most of the lipids are bound to proteins and/or cerebrosides to form complexes, as revealed by the unmasking action of pyridine.Acknowledgements. This work was supported by U.S. PHS grants RR-00165 HD-06087 from National Institute of Health.     

Syringaldazine,an effective reagent for detecting laccase and peroxidase in fungi

Zusammenfassung Das Syringaaldehyd-azin ist eine hellgelbe, kristalline und leicht zu synthetisierende Verbindung, die in verdünnter alkoholischer Lösung von Laccase + Luftsauerstoff bzw. von Peroxydase + H₂O₂ unter Bildung eines intensiv purpurnen Pigments rasch oxydiert wird. Diese hochempfindliche Reaktion ist als Tüpfelprobe leicht anzuwenden und ergibt einen sehr spezifischen Nachweis dieser Phenoloxydasen in Pilzkulturen: Trägt man einige Tropfen verdünnter Azinlösung auf eine Pilzkultur auf, bildet sich an der Luft bei Anwesenheit von Laccase ein purpurner Fleck. Ist nur wenig Laccase vorhanden, wird die Probe nur rosa bis rot; bleibt sie farblos, ist keine Laccase vorhanden. Im letzteren Fall kann man verdünnte H₂O₂-Lösung an derselben Stelle auftropfen, um Peroxydase nachzuweisen. Färbt sich der Fleck dann lila rot, ist eine Peroxydase vorhanden. Der Nachweis von Peroxydase ist bei Anwesenheit von Laccase nicht möglich. Ist keine Laccase vorhanden, kann man eine Furoguajacin-Lösung (bzw. frisch hergestellte Guajaktinktur) an einer anderen Stelle der Kultur auftragen, um Tyrosinase nachzuweisen. Die Tyrosinase oxydiert das Azin überhaupt nicht. Mit Hilfe dieser eindeutigen und schnellen Nachweismethoden wird man den Zusammenhang zwischen der Bildung der verschiedenen Phenoloxydasen durch holz-zerstörende Pilze und deren Abbau von Holz und von Lignin besser untersuchen können.

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Maintained at Madison in cooperation with the University of Wisconsin.     

Possible involvement of the phloem sealing system in the acceptance of a plant as host by an aphid

Possible reasons for the rejection of some lines ofTriticum monococcum (Tm44 and Tm46) by the aphidSitobion avenae were explored. In allT. monococcum lines studied, whether unfavourable (non-host/resistant plant) or favourable (host/susceptible plant), the concentrations of hydroxamic acids, a family of aphid-resistance factors in cereals, were significantly lower than the levels in the favourable host-plantTriticum aestivum cv. Therefore, hydroxamic acids did not account for the host/non-host patterns observed. Phloem sap was collected by stylectomy from young seedlings of favourable and unfavourable plants. In non-aphid-resistant genotypes, the success in stylectomy, the proportion of amputated stylets resulting in long (>1 min) exudations, the average duration of exudation, and the final volume of sap exuded, were higher than in the aphid-resistant genotypes. It is concluded that aphid interference with the phloem sealing system of the plant is a likely mechanism of rejection ofT. monococcum lines Tm44 and Tm46 as hosts byS. avenae.     

GRW as an ontology of dispositions

The paper argues that the formulation of quantum mechanics proposed by Ghirardi, Rimini and Weber (GRW) is a serious candidate for being a fundamental physical theory and explores its ontological commitments from this perspective. In particular, we propose to conceive of spatial superpositions of non-massless microsystems as dispositions or powers, more precisely propensities, to generate spontaneous localizations. We set out five reasons for this view, namely that (1) it provides for a clear sense in which quantum systems in entangled states possess properties even in the absence of definite values; (2) it vindicates objective, single-case probabilities; (3) it yields a clear transition from quantum to classical properties; (4) it enables to draw a clear distinction between purely mathematical and physical structures, and (5) it grounds the arrow of time in the time-irreversible manifestation of the propensities to localize.     

Ultrastructural localization of newcastle disease virus surface antigen in infected Hela cells as revealed by an enzyme-labelled antibody method

Zusammenfassung Nach indirekter peroxidasekonjugierter Antikörpermethode wurden elektronenmikroskopisch mit Newcastle-Disease-Virus infizierte HeLa-Zellen geprüft, und in den frühen Infektionsstadien an den Ribosomen des endoplasmatischen Retikulums solcher Zellen und in den späten Infektionsstadien an den «Spikes» des spriessenden Viruskörperchens das Antigen der Virusoberflächen gezeigt.     

Hsp70 in parasites: as an inducible protective protein and as an antigen

The heat shock (HS) response is a general homeostatic mechanism that protects cells and the entire organism from the deleterious effects of environmental stresses. It has been demonstrated that heat shock proteins (HSP) play major roles in many cellular processes, and have a unique role in several areas of cell biology, from chronic degenerative diseases to immunology, from cancer research to interaction between host and parasites. This review deals with thehsp70 gene family and with its protein product, hsp70, as an antigen when pathogens infect humans. Members of HSP have been shown to be major antigens of many pathogenic organisms when they experience a major temperature shift upwards at the onset of infection and become targets for host B and T cells.     

Properties of an auxin-oxidising system fromLactobacillus bulgaricus

Résumé Un traitement à l'acide-indolylacétique (IAA) a pour effet d'induire — chezLactobacillus bulgaricus — un système inactivant l'IAA. Le pH optimum de ce complexe enzymatique est de 6.0 et sa température optimale de réaction de 32 °C. Cette induction est inhibée par des analogues de l'IAA (acides-indolyl carboxylique et-indolyl propionique;dl-tryptophane). L'apparition de cette « IAA-oxydase » permet de rendre compte, dans une large mesure, des effets de l'IAA sur la croissance des microorganismes testés.