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Ewa Stach-Chilf Jerzy B. Warchol Prof. Dr. Christoph Pilgrim 《Cell and tissue research》1981,219(2):417-423
Summary The neurohypophysis of donor mice was implanted under the renal capsule of the recipients. The pituicytes survived while the neurosecretory axons disappeared. The ultrastructure of the glial cells was observed seven and nine weeks after transplantation. There were no signs of phagocytotic activity although remnants of axons were still present at seven weeks. The numerous processes of the pituicytes form a network with intercellular spaces wide in younger and narrower in older implants. The cells are connected by desmosomes and gap junctions. Pituicytes as well as blood vessels preserve their organotypic appearance. The transplant thus represents an experimental model for investigations on pituicytes in vivo in the absence of neurosecretory axons.Fellow of the Alexander von Humboldt-Stiftung. On leave from Department of Histology and Embryology, Institute of Biostructure, Academy of Medicine, Pozna, Poland 相似文献
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Mechthilde?MennickenEmail author Wolfgang?Maier Pedro?W.?Crous Franz?Oberwinkler 《Mycological Progress》2005,4(3):215-224
Rust fungi on Aizoaceae in southern Africa have been examined and reported based on 27 specimens collected during a biodiversity
study and previously collected herbarium specimens. Eight species including five new species have been recognized, and they
are described in detail and illustrated. Together with two additional species in literature, ten species of rust fungi are
now recognized on Aizoaceae in southern Africa.
Part 223 in the series “Studies in Heterobasidiomycetes” from the Botanical Institute, University of Tübingen. 相似文献
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Structure-function studies of Escherichia coli RpoH (sigma32) by in vitro linker insertion mutagenesis 下载免费PDF全文
The sigma factor RpoH (sigma(32)) is the key regulator of the heat shock response in Escherichia coli. Many structural and functional properties of the sigma factor are poorly understood. To gain further insight into RpoH regions that are either important or dispensable for its cellular activity, we generated a collection of tetrapeptide insertion variants by a recently established in vitro linker insertion mutagenesis technique. Thirty-one distinct insertions were obtained, and their sigma factor activity was analyzed by using a groE-lacZ reporter fusion in an rpoH-negative background. Our study provides a map of permissive sites which tolerate linker insertions and of functionally important regions at which a linker insertion impairs sigma factor activity. Selected linker insertion mutants will be discussed in the light of known sigma factor properties and in relation to a modeled structure of an RpoH fragment containing region 2. 相似文献
107.
Brundert M Heeren J Merkel M Carambia A Herkel J Groitl P Dobner T Ramakrishnan R Moore KJ Rinninger F 《Journal of lipid research》2011,52(4):745-758
The mechanisms of HDL-mediated cholesterol transport from peripheral tissues to the liver are incompletely defined. Here the function of scavenger receptor cluster of differentiation 36 (CD36) for HDL uptake by the liver was investigated. CD36 knockout (KO) mice, which were the model, have a 37% increase (P = 0.008) of plasma HDL cholesterol compared with wild-type (WT) littermates. To explore the mechanism of this increase, HDL metabolism was investigated with HDL radiolabeled in the apolipoprotein (125I) and cholesteryl ester (CE, [3H]) moiety. Liver uptake of [3H] and 125I from HDL decreased in CD36 KO mice and the difference, i. e. hepatic selective CE uptake ([3H]125I), declined (–33%, P = 0.0003) in CD36 KO compared with WT mice. Hepatic HDL holo-particle uptake (125I) decreased (–29%, P = 0.0038) in CD36 KO mice. In vitro, uptake of 125I-/[3H]HDL by primary liver cells from WT or CD36 KO mice revealed a diminished HDL uptake in CD36-deficient hepatocytes. Adenovirus-mediated expression of CD36 in cells induced an increase in selective CE uptake from HDL and a stimulation of holo-particle internalization. In conclusion, CD36 plays a role in HDL uptake in mice and by cultured cells. A physiologic function of CD36 in HDL metabolism in vivo is suggested. 相似文献
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Sergej Tschernyschkow Sabine Herda Gerd Gruenert Volker Döring Dennis Görlich Antje Hofmeister Christian Hoischen Peter Dittrich Stephan Diekmann Bashar Ibrahim 《Progress in biophysics and molecular biology》2013