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841.
Interleukin-8 is a Cyclosporin A binding protein 总被引:2,自引:0,他引:2
H. Bang K. Brune C. Nager U. Feige 《Cellular and molecular life sciences : CMLS》1993,49(6-7):533-538
Inflammatory immune reactions occur during transplant rejections and autoimmune diseases. Such reactions are mediated by cytokines, including interleukin-8 (IL-8). Cyclosporin A (CsA) exerts immunosuppressive activities1,2 by binding to immunoregulatory proteins termed cyclophilins3. The anti-inflammatory effects of CsA are still not fully understood. Searching for novel neutrophil-activating proteins, we observed that an antiserum against human recombinant Interleukin-8 (IL-8) cross-reacted with cyclophilins in Western blots. Furthermore, native IL-8 was found to specifically bind CsA, whereas biologically inactive analogs of CsA were not bound by IL-8. Putative binding sites for CsA on IL-8 could be identified on the basis of structural similarities between IL-8 and cyclophilin. However, IL-8 lacks peptidyl-prolyl-isomerase (PPlase) enzyme activity, which is regarded as a characteristic of cyclophilins4,5,6. We conclude that the specific binding of CsA to IL-8 may explain some of the anti-inflammatory effects of CsA. IL-8 may be a novel member of the cyclophilins lacking PPlase activity. 相似文献
842.
843.
The Krüppel (Kr) locus is a member of the 'gap' class of segmentation genes of Drosophila melanogaster. Mutations at the Kr locus cause the deletion of contiguous segments from the embryonic body pattern. We have elucidated the spatial and temporal characteristics of Kr gene expression during early embryo development, the localization of cytoplasmic Kr+ activity and its spatial requirement for normal segmentation. 相似文献
844.
Antibiotic inhibition of group I ribozyme function 总被引:21,自引:0,他引:21
The discovery of catalytically active RNA has provided the basis for the evolutionary concept of an RNA world. It has been proposed that during evolution the functions of ancient catalytic RNA were modulated by low molecular weight effectors, related to antibiotics, present in the primordial soup. Antibiotics and RNA may have coevolved in the formation of the modern ribosome. Here we report that a set of aminoglycoside antibiotics, which are known to interact with the decoding region of the 16S ribosomal RNA of Escherichia coli, inhibit the second step of splicing of the T4 phage-derived td intron. Thus catalytic RNA seems to interact not only with a mononucleotide and an amino acid, but also with another class of biomolecules, the sugars. Splicing of other group I introns but not group II introns was inhibited. The similarity in affinity and specificity of these antibiotics for group I introns and rRNAs may result from recognition of evolutionarily conserved structures. 相似文献
845.
846.
847.
Summary Testosterone sulphate has been isolated from the urine of a normal male subject. The characterization of the substance was based upon the following criteria: Identical Rf values of authentic testosterone sulphate and of the unknown compound in the paperchromatographic systemSi; positive methylene blue-reaction and UV contact photogram; identical absorption spectra in concentrated sulphuric acid. Following dioxan solvolysis, only testosterone has been detected. Epitestosterone could not been found.
Die in der Arbeit dargestellten Experimente wurden durch die Deutsche Forschungsgemeinschaft unterstützt. Testosteronsulfat wurde dankenswerterweise durch die Merck A.G., Darmstadt, zur Verfügung gestellt. 相似文献
Die in der Arbeit dargestellten Experimente wurden durch die Deutsche Forschungsgemeinschaft unterstützt. Testosteronsulfat wurde dankenswerterweise durch die Merck A.G., Darmstadt, zur Verfügung gestellt. 相似文献
848.
Pulmonary tumours in rats induced by oral hydrazine sulphate 总被引:2,自引:0,他引:2
849.
N. A. Terragno A. J. Lonigro K. U. Malik J. C. McGiff 《Cellular and molecular life sciences : CMLS》1972,28(4):437-439
Zusammenfassung Nachweis, dass Bradykinin den renalen Blutstrom um 58% der Kontrollwerte (282±40 ml min) erhöht und gleichzeitig im venösen Nierenblut die Konzentration einer Substanz, welche die physicochemischen und biologischen Eigenschatten eines Prostaglandins der E-Serie besitzt, steigert, wobei die Konzentration einer PGF-ähnlichen Substanz unverändert blieb. 相似文献
850.
Summary The enzymes of anaerobic glycolysis are present in the granules of secretion and in the mitochondria of pancreas of guinea pig. On the otherhand, it has not been possible to demonstrate their presence in the soluble phase of the cell. Simultaneous addition of ATP and DPN causes an increase of this activity in both fractions; separate addition of these substances causes an increased activity only in the mitochondrial fraction. 相似文献