Effects of thyrotropin and thiouracil on embryonic chick thyroidin vitro

Zusammenfassung Schilddrüsenanlagen von Hühnerembryonen, in Ambinon-Medium kultiviert, entwickeln sich schneller und zeigen beschleunigte intrafollikuläre Kolloidbildung. Mit Thiourazil behandelte Kulturen liessen retardierte Follikelbildung und Kolloidbildung erkennen.     

Formation of hydroxyapatite nuclei induced by dehydration of calcifying solutions

Zusammenfassung Es wird gezeigt, dass bei Entfernung eines Teiles der wasserlöslichen Phase einer meta-stabilen, verkalkenden Lösung, Kalk- und Phosphorionen so angereichert werden, dass «kristallisierte Kerne» von Hydroxyapatit auftreten.

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This work was supported in part by grant No. DE-02456-03 from the National Institute of Dental Research, National Institutes of Health and by contract No. 4234 (00) with the Office of Naval Research, Department of the Navy.     

Transvascular passage of albumin-I131 into skin of immunized mice

Zusammenfassung Mäuse wurden mit Kasein- und Streptokokkus-Antigen injiziert. In den immunisierten Tieren ist die Ausscheidungsgeschwindigkeit von i.v. injiziertem Albumin-I¹³¹ aus dem Plasma erniedrigt, und ebenso ist im Vergleich zu den Kontrolltieren der transvaskuläre Transport in die Haut reduziert.     

Purification of a protein binding quinacrine and histrionicotoxin from membrane fragments rich in cholinergic receptors in Torpedo marmorata]

A protein is purified by differential centrifugation from membrane fragments rich in acetylcholine receptor prepared from Torpedo marmorata electric organ after dissolution by a mixture of non denaturing detergents. After polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate and Coomassie blue staining the purified protein yields a single band of apparent molecular weight 43,000. Spectroscopic experiments carried out in the absence of Ca++ and detergents reveal that the 43 K protein interacts with the fluorescent local anesthetic quinacrine and with the frog toxin histrionicotoxin (apparent KD : 7 X 10(-7) M) but not with carbamylcholine and the alpha toxin from N. nigricollis.     

Insight into tubulin regulation from a complex with colchicine and a stathmin-like domain

Microtubules are cytoskeletal polymers of tubulin involved in many cellular functions. Their dynamic instability is controlled by numerous compounds and proteins, including colchicine and stathmin family proteins. The way in which microtubule instability is regulated at the molecular level has remained elusive, mainly because of the lack of appropriate structural data. Here, we present the structure, at 3.5 A resolution, of tubulin in complex with colchicine and with the stathmin-like domain (SLD) of RB3. It shows the interaction of RB3-SLD with two tubulin heterodimers in a curved complex capped by the SLD amino-terminal domain, which prevents the incorporation of the complexed tubulin into microtubules. A comparison with the structure of tubulin in protofilaments shows changes in the subunits of tubulin as it switches from its straight conformation to a curved one. These changes correlate with the loss of lateral contacts and provide a rationale for the rapid microtubule depolymerization characteristic of dynamic instability. Moreover, the tubulin-colchicine complex sheds light on the mechanism of colchicine's activity: we show that colchicine binds at a location where it prevents curved tubulin from adopting a straight structure, which inhibits assembly.     

Systemic Research Practices Towards the Development of an Eco-Community in Vietnam: some Joint Post-Facto Reflections

In this article we discuss how an interdisciplinary research team partnered with a variety of stakeholders concerned with and/or affected by the impacts of climate change in the Red River Delta of Vietnam. The research, undertaken from 2016 to 2018, drew upon a wide range of methods to investigate systemically these impacts – with a view to the research inputting into the development of (more) sustainable ways of living. The research solicited various accounts of the experience of climate change in the community, set up learning processes in community meetings, and created an interface with government officials positioned at commune, district, provincial, and national levels. The intention was to offer support towards developing a learning process (broadly defined as including learnings/systemic inquiry across organizational levels of the society) to pursue options for sustainable living. The article offers our post-facto reflections which render more explicit (to ourselves and for the benefit of audiences) how the research team, with Hoang as lead researcher, facilitated the inquiry process towards developing a synthesis which underscored the assets for resilience to climate change and supported interventions to strengthen such (defined) assets.

     

The action of cortisone on the embryonic cartilage and musclein vitro

Zusammenfassung Cortison verzögert das Wachstum von embryonalen Femur-Anlagen und hemmt die hypertrophische Entwicklung des Knorpelsin vitro, fördert aber die Differenzierung der gestreiften Myoblasten.