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91.
Hayley K. Charlton 《Biochemical and biophysical research communications》2010,392(2):234-239
The pleiotropic effects of the insulin-sensitizing adipokine adiponectin are mediated, at least in part, by two seven-transmembrane domain receptors AdipoR1 and AdipoR2. Recent reports indicate a role for AdipoR-binding proteins, namely APPL1, RACK1 and CK2β, in proximal signal transduction events. Here we demonstrate that endoplasmic reticulum protein 46 (ERp46) interacts specifically with AdipoR1 and provide evidence that ERp46 modulates adiponectin signalling. Co-immunoprecipitation followed by mass spectrometry identified ERp46 as an AdipoR1-, but not AdipoR2-, interacting protein. Analysis of truncated constructs and GST-fusion proteins revealed the interaction was mediated by the cytoplasmic, N-terminal residues (1-70) of AdipoR1. Indirect immunofluorescence microscopy and subcellular fractionation studies demonstrated that ERp46 was present in the ER and the plasma membrane (PM). Transient knockdown of ERp46 increased the levels of AdipoR1, and AdipoR2, at the PM and this correlated with increased adiponectin-stimulated phosphorylation of AMPK. In contrast, adiponectin-stimulated phosphorylation of p38MAPK was reduced following ERp46 knockdown. Collectively these results establish ERp46 as the first AdipoR1-specific interacting protein and suggest a role for ERp46 in adiponectin receptor biology and adiponectin signalling. 相似文献
92.
93.
The fluorochrome pattern produced by DA/DAPI double staining in Pan paniscus chromosomes is reported. The location of DA/DAPI prominent bands differs from that reported for all other hominoid species. However, the pattern in the pygmy chimpanzee is most similar to that seen in Pan troglodytes. Comparison of the DA/DAPI pattern of the other hominoid species allows the construction of a proposed hominoid ancestral karyotype and a preliminary phylogenetic reconstruction of DA/DAPI bands for the great apes and man. 相似文献
94.
95.
The reactivity of sonicated phosphatidylcholine-cholesterol liposomes with cholesterol : oxygene oxydoreductase, an enzyme which catalyses the oxidation of the 3 beta hydroxyl group of cholesterol to a ketone group, is compared with that of ternary system phosphatidylcholine-cholesterol-Thesit. Regardless to the phosphatidylcholines nature and the phosphatidylcholine/cholesterol molar ratio (R), the enzymatic oxidation rate of liposomal cholesterol is slower than when the reaction is developed in the present of Thesit, a surfactif agent which destroyes the lamellar particles. This is true whether Thesit is added during preparation of dispersions or during incubation with cholesterol oxydase. The enzymatic oxydation rate of cholesterol of ternary systems phosphatidylcholine-cholesterol-Thesit is independent of the (R) value and the phosphatidylcholine fatty acid unsaturation, whereas that of phosphatidylcholine-cholesterol dispersions depends on these two parameters. The reaction rate increases in the order: dipalmitoylphosphatidylcholine to yolk egg phosphatidylcholines, and dioleylphosphatidylcholine. The optimal conditions for cholesterol oxidation were found to be R = 0.5. This result is not affected by the phosphatidylcholines nature. In order to explain these data, various hypotheses are considered. In particular, the weak liposomal cholesterol reactivity with cholesterol oxidase could result from an inhibitory effect on the enzyme-substrate combination due to the polar phosphorylcholine groups. 相似文献
96.
97.
Frantiek Hindák 《Hydrobiologia》2000,438(1-3):107-116
Morphological variation of trichomes, heterocytes and akinetes in four species classified into the nostocalean genera Aphanizomenon Morren ex Bornet et Flahault or Anabaena Bory (Cyanophyta/Cyanobacteria) was studied from natural samples by LM and illustrated by drawings and micrographs. All investigated species, Aphanizomenon gracile (Lemmerm.) Lemmerm., A. aphanizomenoides (Forti) Komárek et Horecká, Anabaena bergii Ostenfeld, A. minderi Huber-Pestalozzi, occur in the plankton as solitary trichomes, similar to many representatives of the genus Anabaena. Main generic diagnostic characters of Aphanizomenon and Anabaena are discussed. 相似文献
98.
Berthold Lausen Torsten Hothorn Frank Bretz Martin Schumacher 《Biometrical journal. Biometrische Zeitschrift》2004,46(3):364-374
The identification and assessment of prognostic factors is one of the major tasks in clinical research. The assessment of one single prognostic factor can be done by recently established methods for using optimal cutpoints. Here, we suggest a method to consider an optimal selected prognostic factor from a set of prognostic factors of interest. This can be viewed as a variable selection method and is the underlying decision problem at each node of various tree building algorithms. We propose to use maximally selected statistics where the selection is defined over the set of prognostic factors and over all cutpoints in each prognostic factor. We demonstrate that it is feasible to compute the approximate null distribution. We illustrate the new variable selection test with data of the German Breast Cancer Study Group and of a small study on patients with diffuse large B‐cell lymphoma. Using the null distribution for a p‐value adjusted regression trees algorithm, we adjust for the number of variables analysed at each node as well. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
99.
The luminol test for blood was carried out on a set of interior fittings and surfaces inside three different makes of modern motor car. The surfaces and fittings provided little interference with the test for blood, although there was some detectable chemiluminescence when the test was applied to blood-free material from a seatbelt, a boot-lining and a gear-knob. The case with which haemoglobin samples could be washed off interior car surfaces was also examined for seat fabrics, carpets, roof-linings and various other plastic interior surfaces. A standard wash with water alone was not very effective and removed only ca. 50% of the haemoglobin. A standard wash with soapy water or with a proprietary multipurpose car cleaner removed ca. 90% of the haemoglobin from the tested surface. The effect of high car interior temperatures on haemoglobin samples that were subsequently used in the luminol test was also examined. It was shown that the sensitivity of the luminol test was not decreased but was increased by the prior heating of a haemoglobin sample. This effect was attributed to the thermal conversion of haemoglobin to the more brighter catalyst for chemiluminescence, methaemoglobin. The enthalpy of this conversion in the solid state was found to be 14.1 kJ/mol. 相似文献
100.