Übereinstimmung positiver und negativer Dopareaktiönen an Gefrierschnitten mit jenen an Extrakten

Zusammenfassung WährendChodat (1922),Meirowsky (1923) undPrzibram (1921) eine spezifische Dopaoxydase ablehnen, da nach des letzteren Befunden das 3, 4 Dioxyphenylalanin sowohl spontan als auch bei Alkali- oder Tyrosinasezusatz sich schwärzt, hältBloch an der Spezifität der Dopase und an ihrem Nachweis durch Dopazusatz fest. Gegenüber den vergeblichen Versuchen, die Dopase zu isolieren, beruft er sich auf die Verschiedenheit der benutzten Methoden. Diesen Einwand könnte er auch den VersuchenSatos undBrechers (1923 u. d. Heft) wegen des ebenfalls negativen Ausfalles der für Dopa charakteristischen Reaktionen (mit Eisenchlorid Grünfärbung, dann bei Natriumkarbonatzusatz Umschlag nach Purpurrot usw.) in den Extrakten der melaninbildenden Gewebe machen. Seiner Forderung nach Anwendung der Gefrierschnittmethode folgend, wurden nur solche namentlich von denselben Objekten, die er verwendet hatte, mikrochemisch auf Dopa untersucht. Weder Augen noch schwarze oder weiße Stellen einer 7 Tage alten oder älteren Ratte noch die Kopfhaut von Menschen zeigten die erwähnte Grünbzw. Rotfärbung. Ebenso negativ fielen die analogen Proben an Puppen verschiedenen Farbtypus vonVanessa urticae aus, ferner am Kokon desBombyx mori.Hingegen zeigten die Gefrierschnitte der Kokone vonSaturnia pavonia undEriogaster lanestris, an denenPrzibram (1922) mittels Extraktion durch Wasser den Dopanachweis in der Eprouvette erbracht hatte, deutlich positiven Ausfall.Es besteht demnach keine Veranlassung, einen Unterschied in der Feststellbarkeit von Dopa anzunehmen, je nachdem man Gefrierschnitt oder Extrakt untersucht.Ein Auszug dieser Arbeit erschien unter dem Titel: Mitteilungen aus der Biologischen Versuchsanstalt der Akademie der Wissenschaften, Zoologische Abteilung, VorstandH. Przibram, Nr. 108. Übereinstimmung positiver und negativer Dopareaktionen an Gefrierschnitten mit jenen an Extrakten (zugleich: Ursachen tierischer Farbkleidung. XI) vonLeonore Brecher undFerdinand Winkler im Akademischen Anzeiger der Akademie der Wissenschaften in Wien, Nr. 17, 1923.     

8,6-Hydroxy dehydrozaluzanin C from Andryala pinnatifida

The roots of Andryala pinnatifida afforded 8β-hydroxy dehydrozaluzanin C.     

Dimeric chromenes and mixed dimers of a chromene with euparin from Encelia canescens

The investigation of Encelia canescens afforded, in addition to several known compounds, four new dimeric p-hydroxyacetophenone derivatives, two epimeric chromene dimers and two epimeric mixed dimers of euparin and encecalin. Furthermore, derivatives of tremetone and of encecalin were present. The structures were elucidated hy high field ¹H NMR spectroscopy.     

Endemische Phytoassoziationen aus den Rumänischen Karpaten

The importance of endemic species for plant communities in the Roumanian Carpathians Mts. has been studied and discussed. Associations of the classAsplenietea trichomanis endemic in the South Carpathians were surveyed; they were classified into some endemic alliances (Gypsophilion petraeae, Micromerion pulegii, andSilenion lerchenfeldianae). Their locus classicus, nomenclatoric type and present distribution were also given.     

Dosimétrie in vivo par OSL,en ligne par fibre optique,pour l’assurance qualité des traitements par radiothérapie externe : le projet ANR-TECSAN Codofer

The Codofer Project (2007–2009), led under the ANR-TECSAN Call, was coordinated by CEA LIST, in partnership with IGR and the Fimel company. The aim of the project was to design and test both metrologically and in clinical conditions OSL optical fiber sensors dedicated to in vivo dosimetry during external beam radiation therapy treatment with high-energy electrons. This study, combined with the results of clinical tests obtained within the European Project Maestro, has demonstrated the advantages of OSL/FO dosimetry for providing quality assurance of treatments. However, the French market for dosimetry has greatly changed as a result of the rules edicted by the French government in 2007. The OSL/FO product is now targeted for other treatment modalities lacking suitable dosimeters (ANR-INTRADOSE Project [2009–2011]).     

Depicting the Spatial Distribution of Proteins in Human Tumor Tissue Combining SELDI and MALDI Imaging and Immunohistochemistry

Carcinoma tissue consists of not only tumor cells but also fibroblasts, endothelial cells or vascular structures, and inflammatory cells forming the supportive tumor stroma. Therefore, the spatial distribution of proteins that promote growth and proliferation in these complex functional units is of high interest. Matrix-assisted laser desorption/ionization imaging mass spectrometry is a newly developed technique that generates spatially resolved profiles of protein signals directly from thin tissue sections. Surface-enhanced laser desorption/ionization mass spectrometry (MS)combined with tissue microdissection allows analysis of defined parts of the tissue with a higher sensitivity and a broader mass range. Nevertheless, both MS-based techniques have a limited spatial resolution. IHC is a technique that allows a resolution down to the subcellular level. However, the detection and measurement of a specific protein expression level is possible only by semiquantitative methods. Moreover, prior knowledge about the identity of the proteins of interest is necessary. In this study, we combined all three techniques to gain highest spatial resolution, sensitivity, and quantitative information. We used frozen tissue from head and neck tumors and chose two exemplary proteins (HNP1–3 and S100A8) to highlight the advantages and disadvantages of each technique. It could be shown that the combination of these three techniques results in congruent but also synergetic data. (J Histochem Cytochem 58:929–937, 2010)     

WWP-1 Is a Novel Modulator of the DAF-2 Insulin-Like Signaling Network Involved in Pore-Forming Toxin Cellular Defenses in Caenorhabditis elegans

Pore-forming toxins (PFTs) are the single largest class of bacterial virulence factors. The DAF-2 insulin/insulin-like growth factor-1 signaling pathway, which regulates lifespan and stress resistance in Caenorhabditis elegans, is known to mutate to resistance to pathogenic bacteria. However, its role in responses against bacterial toxins and PFTs is as yet unexplored. Here we reveal that reduction of the DAF-2 insulin-like pathway confers the resistance of Caenorhabditis elegans to cytolitic crystal (Cry) PFTs produced by Bacillus thuringiensis. In contrast to the canonical DAF-2 insulin-like signaling pathway previously defined for aging and pathogenesis, the PFT response pathway diverges at 3-phosphoinositide-dependent kinase 1 (PDK-1) and appears to feed into a novel insulin-like pathway signal arm defined by the WW domain Protein 1 (WWP-1). In addition, we also find that WWP-1 not only plays an important role in the intrinsic cellular defense (INCED) against PFTs but also is involved in innate immunity against pathogenic bacteria Pseudomonas aeruginosa and in lifespan regulation. Taken together, our data suggest that WWP-1 and DAF-16 function in parallel within the fundamental DAF-2 insulin/IGF-1 signaling network to regulate fundamental cellular responses in C. elegans.     

Studien über Pigmentbildung

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