The incorporation of45Ca into the egg of the Medaka,Oryzias latipes

Zusammenfassung Zur Markierung des intrazellulären Ca im Fisch-Ei wurde⁴⁵CaCl₂-enthaltende Ringer-Lösung in die Abdominalhöhle vonOryzias latipes injiziert. 2–3 Tage nach der Injektion zeigt die Radioaktivität der abgelegten Eier ihr Maximum und nimmt dann allmählich ab. Aus Mikroautoradiogrammen der abgelegten Eier geht hervor, dass⁴⁵Ca im Chorion und innerhalb des Eies eingebaut wird.     

酸性染料/三乙胺盐的蒸汽压在尼纶热熔染色中的应用

在纤维染色中很重要的一个方法是利用染料的升华作用,热熔染色和转移印花都是典型的例子,常用的非离子型染料,主要因为非离子染料的蒸汽压比较大,离子型的染料,例如酸性染料就不能进行热熔染色,本文中,成功地将酸性染料用三乙胺处理,形成的盐具有较大的蒸汽压,可以通过气相色谱测定出蒸汽压值,并利用这种盐的升华性,使尼纶织物可以用酸性染料热熔染色。     

Cloning and expression of a cDNA encoding an endothelin receptor

Endothelins are a newly described peptide family consisting of three peptides (ET-1, ET-2 and ET-3) which are the most potent vasoconstrictive peptides known. They are crucial in the regulation of vascular smooth muscle tone. The diverse functions of endothelins are thought to be mediated by interaction with many different receptors coupled to the inositol phosphate/calcium ion messenger pathway. However, because of the structural resemblance of the three peptides, the presence and nature of multiple endothelin receptors remain to be elucidated. We report here the cloning of a complementary DNA encoding a bovine endothelin receptor, which has a transmembrane topology similar to that of other G protein-coupled receptors and shows specific binding, with the highest selectivity to ET-1 in animal cells transfected with the cloned cDNA. This receptor messenger RNA is widely distributed in the central nervous system and peripheral tissues, particularly in the heart and lung. Our results support the view that there are other receptor subtypes.     

Two-photon laser spectroscopy of antiprotonic helium and the antiproton-to-electron mass ratio

Physical laws are believed to be invariant under the combined transformations of charge, parity and time reversal (CPT symmetry). This implies that an antimatter particle has exactly the same mass and absolute value of charge as its particle counterpart. Metastable antiprotonic helium (pHe(+)) is a three-body atom consisting of a normal helium nucleus, an electron in its ground state and an antiproton (p) occupying a Rydberg state with high principal and angular momentum quantum numbers, respectively n and l, such that n?≈?l?+?1?≈?38. These atoms are amenable to precision laser spectroscopy, the results of which can in principle be used to determine the antiproton-to-electron mass ratio and to constrain the equality between the antiproton and proton charges and masses. Here we report two-photon spectroscopy of antiprotonic helium, in which p(3)He(+) and p(4)He(+) isotopes are irradiated by two counter-propagating laser beams. This excites nonlinear, two-photon transitions of the antiproton of the type (n, l)?→?(n?-?2, l?-?2) at deep-ultraviolet wavelengths (λ = 139.8, 193.0 and 197.0?nm), which partly cancel the Doppler broadening of the laser resonance caused by the thermal motion of the atoms. The resulting narrow spectral lines allowed us to measure three transition frequencies with fractional precisions of 2.3-5 parts in 10(9). By comparing the results with three-body quantum electrodynamics calculations, we derived an antiproton-to-electron mass ratio of 1,836.1526736(23), where the parenthetical error represents one standard deviation. This agrees with the proton-to-electron value known to a similar precision.     

Synthesis of an analog of human calcitonin gene related peptide, [Asu2,7]-h-CGRP

Summary The analog of h-CGRP, des-Ala-deamino-dicarba-h-CGRP, was synthesized by the combination of the conventional solution and the solid phase peptide synthesis methods. This analog showed stronger and longer-lasting hypocalcemic and hypophosphatemic activities than the natural hormone.30 September 1986     

Platelet aggregation is inhibited by phycolectins

Lectins from four marine algal species were examined for interaction with human platelets. The lectin designated hypnin A, from the red algaHypnea japonica, inhibited adenosine diphosphate (ADP)-or collagen-induced human platelet aggregation in a dose-dependent manner. Complete inhibition was observed at concentrations of 100 and 5 g/ml of the lectin with, ADP (2 M) and collagen (0.2 g/ml)-induced platelet aggregation, respectively. At the inhibitory concentration of 0.5 to 100 g/ml, the lectin did not induce aggregation of resting platelets. Lectins from the other three algal species also inhibited ADP-induced human platelet aggregation. These results indicate that the algal lectins are a new group of inhibitors and may be useful to study glycoconjugates on platelet membranes and to design novel platelet aggregation inhibitors.     

A blue-light-activated adenylyl cyclase mediates photoavoidance in Euglena gracilis

Blue light regulates processes such as the development of plants and fungi and the behaviour of microbes. Two types of blue-light receptor flavoprotein have been identified: cryptochromes, which have partial similarity to photolyases, and phototropins, which are photoregulated protein kinases. The former have also been found in animals with evidence of essential roles in circadian rhythms. Euglena gracilis, a unicellular flagellate, abruptly changes its swimming direction after a sudden increase or decrease in incident blue light intensity, that is, step-up or step-down photophobic responses, resulting in photoavoidance or photoaccumulation, respectively. Although these photobehaviours of Euglena have been studied for a century, the photoreceptor molecules mediating them have remained unknown. Here we report the discovery and biochemical characterization of a new type of blue-light receptor flavoprotein, photoactivated adenylyl cyclase, in the photoreceptor organelle of Euglena gracilis, with molecular genetic evidence that it mediates the step-up photophobic response.     

Verkürzte Methode zur Isolierung radiochemisch reinen Chlorophylls

Summary Radiochemically pure chlorophylla andb have been separated from barley by a rapid two-step purification procedure. It is based on chromatographic separation of pigments on polyamide columns and by paper chromatography.