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991.
992.
Adipose triglyceride lipase-mediated lipolysis of cellular fat stores is activated by CGI-58 and defective in Chanarin-Dorfman Syndrome 总被引:3,自引:0,他引:3
Lass A Zimmermann R Haemmerle G Riederer M Schoiswohl G Schweiger M Kienesberger P Strauss JG Gorkiewicz G Zechner R 《Cell metabolism》2006,3(5):309-319
Adipose triglyceride lipase (ATGL) was recently identified as an important triacylglycerol (TG) hydrolase promoting the catabolism of stored fat in adipose and nonadipose tissues. We now demonstrate that efficient ATGL enzyme activity requires activation by CGI-58. Mutations in the human CGI-58 gene are associated with Chanarin-Dorfman Syndrome (CDS), a rare genetic disease where TG accumulates excessively in multiple tissues. CGI-58 interacts with ATGL, stimulating its TG hydrolase activity up to 20-fold. Alleles of CGI-58 carrying point mutations associated with CDS fail to activate ATGL. Moreover, CGI-58/ATGL coexpression attenuates lipid accumulation in COS-7 cells. Antisense RNA-mediated reduction of CGI-58 expression in 3T3-L1 adipocytes inhibits TG mobilization. Finally, expression of functional CGI-58 in CDS fibroblasts restores lipolysis and reverses the abnormal TG accumulation typical for CDS. These data establish an important biochemical function for CGI-58 in the lipolytic degradation of fat, implicating this lipolysis activator in the pathogenesis of CDS. 相似文献
993.
Regulation of hair follicle development by the TNF signal ectodysplasin and its receptor Edar 总被引:15,自引:0,他引:15
Laurikkala J Pispa J Jung HS Nieminen P Mikkola M Wang X Saarialho-Kere U Galceran J Grosschedl R Thesleff I 《Development (Cambridge, England)》2002,129(10):2541-2553
X-linked and autosomal forms of anhidrotic ectodermal dysplasia syndromes (HED) are characterized by deficient development of several ectodermal organs, including hair, teeth and exocrine glands. The recent cloning of the genes that underlie these syndromes, ectodysplasin (ED1) and the ectodysplasin A receptor (EDAR), and their identification as a novel TNF ligand-receptor pair suggested a role for TNF signaling in embryonic morphogenesis. In the mouse, the genes of the spontaneous mutations Tabby (Ta) and downless (dl) were identified as homologs of ED1 and EDAR, respectively. To gain insight into the function of this signaling pathway in development of skin and hair follicles, we analyzed the expression and regulation of Eda and Edar in wild type as well as Tabby and Lef1 mutant mouse embryos. We show that Eda and Edar expression is confined to the ectoderm and occurs in a pattern that suggests a role of ectodysplasin/Edar signaling in the interactions between the ectodermal compartments and the formation and function of hair placodes. By using skin explant cultures, we further show that this signaling pathway is intimately associated with interactions between the epithelial and mesenchymal tissues. We also find that Ta mutants lack completely the placodes of the first developing tylotrich hairs, and that they do not show patterned expression of placodal genes, including Bmp4, Lef1, Shh, Ptch and Edar, and the genes for beta-catenin and activin A. Finally, we identified activin as a mesenchymal signal that stimulates Edar expression and WNT as a signal that induces Eda expression, suggesting a hierarchy of distinct signaling pathways in the development of skin and hair follicles. In conclusion, we suggest that Eda and Edar are associated with the onset of ectodermal patterning and that ectodysplasin/edar signaling also regulates the morphogenesis of hair follicles. 相似文献
994.
Josef Kirchhoff Walter Reinhardt Wolfgang Grünke Rüdiger Ghraf Peter Ball Rudolf Knuppen 《Journal of neurochemistry》1983,40(2):474-480
The ability of catecholestrogens to induce cytosolic progestin binding sites in the hypothalamus, pituitary gland, and uterus of ovariectomised-adrenalectomised rats was demonstrated by the increase in high-affinity [3H]promegestone binding sites (KD 1.39, 0.50, and 0.54 nM, respectively) following a single subcutaneous injection (26.4 micrograms/animal) of the 3.4-dibenzoate ester of 4-hydroxyestradiol. The affinity and the time course of induction of these binding sites were very similar to those after a single injection of an equivalent dose (20 micrograms/animal) of estradiol 3-benzoate, exhibiting maximal receptor levels after 44 h. Widely differing efficacies in the induction of progestin binding sites were observed between the dibenzoate esters of 2- and 4-hydroxyestradiol. 2-Hydroxyestradiol 2,3-dibenzoate was ineffective in the pituitary gland up to a dose of 132 micrograms/animal, whereas 4-hydroxyestradiol dibenzoate was equipotent to estradiol benzoate, showing a maximal induction of progestin binding sites at single doses in the range of 13.2-26.4 micrograms/animal (equivalent to 10-20 micrograms of estradiol benzoate). As compared to the pituitary gland, the uterus was much more sensitive to the systemic administration of estrogen benzoates. At single doses in the range of 1.32-6.6 micrograms/animal (equivalent to 1-5 micrograms of estradiol benzoate), 4-hydroxyestradiol dibenzoate induced maximal levels of progestin receptors, and even 2-hydroxyestradiol dibenzoate, when given at a high dose (132.4 micrograms/animal, equivalent to 100 micrograms of estradiol benzoate), produced a slight increase in progestin binding sites. 相似文献
995.
Immuno- and lectin histochemistry of epithelial subtypes and their changes in a radiation-induced lung fibrosis model of the mini pig 总被引:7,自引:0,他引:7
Michael Kasper Thomas Rudolf Regina Hahn Ingrid Peterson Martin Müller 《Histochemistry and cell biology》1993,100(5):367-377
Cell types of lung epithelia of mini pigs have been studied using a panel of monoclonal and polyclonal antibodies against cytokeratins (CKs) and vimentin and three lectins before and after radiation-induced fibrosis. In normal tissues, CK18 specific antibodies reacted above all with type II alveolar epithelial cells, while CK7 and pan CK-specific antibodies stained the whole alveolar epithelium. In bronchial epithelial cells, CKs 7, 8, 18 and focally CKs 4 and 13 as well as vimentin were found. Cell specificity of the CK pattern was confirmed by double label immunofluorescence using type II cell-specific Maclura pomifera (MPA) lectin, type I cell specific Lycopersicon esculentum (LEA) lectin and capillary endothelium-binding Dolichos biflorus (DBA) lectin. In experimental pulmonary fibrosis, enhanced coexpression of CK and vimentin was observed in bronchial epithelium. Subtypes of alveolar epithelial cells were no longer easily distinguishable. CK18 was found to be expressed in the entire alveolar epithelium. The gradual loss of the normal alveolar epithelial marker, as seen by the binding of MPA to type I-like cells, of LEA to type II-like cells and the partial loss of MPA-binding to type II cells, was paralleled by the appearance of CK4, typical for squamous epithelia, and the occurrence of DBA-binding in epithelial cells. Implications of these results for general concepts of intermediate filament protein expression and lectin binding in the fibrotic process are discussed. 相似文献
996.
997.
Rudolf Amann Wolfgang Ludwig Werner Laubinger Peter Dimroth Karl Heinz Schleifer 《FEMS microbiology letters》1988,56(3):253-259
Abstract The gene coding for the β-subunit of the sodium ion translocating ATP synthase from Propionigenium modestum was cloned and sequenced. The predicted amino acid sequence resembles that of the β-subunits from proton-translocating ATP synthases. The same conserved regions are found in both types of ATP synthases. This is a good indication that the β-subunits of the proton and sodium ion translocating ATP synthases have evolved from a common ancestor. 相似文献
998.
Michael Sommerauer Carmen Graf Niklaus Sch?fer Gerhard Huber Paul Schneider Rudolf Wüthrich Christoph Schmid Hans Steinert 《PloS one》2015,10(6)
Purpose
Despite recommendations for 99mTc-tetrofosmin dual tracer imaging for hyperparathyroidism in current guidelines, no report was published on dual-isotope 99mTc-tetrofosmin and 123I sodium iodide single-photon-emission-computed-tomography (SPECT). We evaluated diagnostic accuracy and the impact of preoperative SPECT on the surgical procedures and disease outcomes.Methods
Analysis of 70 consecutive patients with primary hyperparathyroidism and 20 consecutive patients with tertiary hyperparathyroidism. Imaging findings were correlated with surgical results. Concomitant thyroid disease, pre- and postoperative laboratory measurements, histopathological results, type and duration of surgery were assessed.Results
In primary hyperparathyroidism, SPECT had a sensitivity of 80% and a positive predictive value of 93% in patient-based analysis. Specificity was 99% in lesion-based analysis. Patients with positive SPECT elicit higher levels of parathyroid hormone and higher weight of resected parathyroids than SPECT-negative patients. Duration of parathyroid surgery was on average, approximately 40 minutes shorter in SPECT-positive than in SPECT-negative patients (89±46 vs. 129±41 minutes, p=0.006); 86% of SPECT-positive and 50% of SPECT-negative patients had minimal invasive surgery (p = 0.021). SPECT had lower sensitivity (60%) in patients with tertiary hyperparathyroidism; however, 90% of these patients had multiple lesions and all of these patients had bilateral lesions.Conclusion
Dual-isotope SPECT with 99mTc-tetrofosmin and 123I sodium iodide has a high diagnostic value in patients with primary hyperparathyroidism and allows for saving of operation time. Higher levels of parathyroid hormone and higher glandular weight facilitated detection of parathyroid lesion. Diagnostic accuracy of preoperative imaging was lower in patients with tertiary hyperparathyroidism. 相似文献999.
Gaurav Vaidya Rudolf Meier 《Cladistics : the international journal of the Willi Hennig Society》2011,27(2):171-180
We present SequenceMatrix, software that is designed to facilitate the assembly and analysis of multi‐gene datasets. Genes are concatenated by dragging and dropping FASTA, NEXUS, or TNT files with aligned sequences into the program window. A multi‐gene dataset is concatenated and displayed in a spreadsheet; each sequence is represented by a cell that provides information on sequence length, number of indels, the number of ambiguous bases (“Ns”), and the availability of codon information. Alternatively, GenBank numbers for the sequences can be displayed and exported. Matrices with hundreds of genes and taxa can be concatenated within minutes and exported in TNT, NEXUS, or PHYLIP formats, preserving both character set and codon information for TNT and NEXUS files. SequenceMatrix also creates taxon sets listing taxa with a minimum number of characters or gene fragments, which helps assess preliminary datasets. Entire taxa, whole gene fragments, or individual sequences for a particular gene and species can be excluded from export. Data matrices can be re‐split into their component genes and the gene fragments can be exported as individual gene files. SequenceMatrix also includes two tools that help to identify sequences that may have been compromised through laboratory contamination or data management error. One tool lists identical or near‐identical sequences within genes, while the other compares the pairwise distance pattern of one gene against the pattern for all remaining genes combined. SequenceMatrix is Java‐based and compatible with the Microsoft Windows, Apple MacOS X and Linux operating systems. The software is freely available from http://code.google.com/p/sequencematrix/ . © The Willi Hennig Society 2010. 相似文献
1000.
Wube AA Hüfner A Thomaschitz C Blunder M Kollroser M Bauer R Bucar F 《Bioorganic & medicinal chemistry》2011,19(1):567-579
A series of 23 new 1-methyl-2-alkenyl-4(1H)quinolones have been synthesized and evaluated in vitro for their antimycobacterial activities against fast growing species of mycobacteria, such as Mycobacterium fortuitum, M. smegmatis and M. phlei. The compounds displayed good to excellent inhibition of the growth of the mycobacterial test strains with improved antimycobacterial activity compared to the hit compound, evocarpine. The most active compounds, which possessed chain length of 11-13 carbons at position-2 displayed potent inhibitory effects with an MIC value of 1.0 mg/L. In a human diploid embryonic lung cell line, MRC-5 cytotoxicity assay, the alkaloids showed weak to moderate cytotoxic activity. Biological evaluation of these evocarpine analogues on the less pathogenic fast growing strains of mycobacteria showed an interesting antimycobacterial profile and provided significant insight into the structure-activity relationships. 相似文献