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41.
Two prohormones for gastrin-releasing peptide are encoded by two mRNAs differing by 19 nucleotides. 总被引:5,自引:3,他引:2
E R Spindel M D Zilberberg J F Habener W W Chin 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(1):19-23
In our studies on the molecular biology of human gastrin-releasing peptide (GRP), we have discovered an example of a change in translational reading frame apparently produced through alternative RNA splicing. Complementary DNAs prepared from a pulmonary carcinoid tumor rich in GRP immunoreactivity had one of two different-sized internal DNA fragments after digestion with the restriction enzyme Pvu II. Nucleotide sequences of the two DNA fragments were identical except for 19 additional nucleotides present in the larger fragment. The region of the mRNA containing the 19 nucleotides corresponded to the carboxyl-terminal region of the human GRP precursor. The resulting shift in reading frame causes a difference of 10 amino acids in size and an overall sequence difference of 27 amino acids between the two GRP prohormones so formed. The change in reading frame described here is unusual in eukaryotes and is yet another mechanism to produce diversity in the generation of biological peptides. 相似文献
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The gut-stimulating principle in Croton penduliflorus seed oil isolated as white crystals (CP crystals) significantly reduced pentobarbitone-induced sleeping time in mice at doses of 3 and 6 mg/kg intraperitoneally. Indomethacin (4 mg/kg) and atropine (0.044 mg/kg) significantly reversed the action of CP crystals on pentobarbitone sleeping time with indomethacin having a profound reversal effect. CP crystals significantly reduced the mean onset of convulsions and the mean death time in mice treated with a surely convulsive dose of strychnine. CP crystals significantly reduced the intensity of morphine and pethidine analgesia and prolonged the duration of pethidine analgesia. Most actions of CP crystals suggest that it stimulates the CNS and reduces the intensity of opioids (except codeine) while prolonging their duration of analgesic action. 相似文献
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Jan Kaehler Anika Tuleweit Daniel Steven Tanja Krempl Antje Haar Marion Carstensen Ralf Koester Wolfram Terres Thomas Meinertz 《Journal of investigative medicine》2006,54(8):446-454
Eotaxin (CCL11) is a potent chemoattractant for eosinophils and lymphocytes. Apart from its functions in the eosinophilic system, eotaxin has been shown to be overexpressed in atherosclerosis. We therefore sought to determine whether chronic infection with Chlamydia pneumoniae or other infectious agents is correlated with concentrations of eotaxin or C-reactive protein since this mechanism could explain the finding that chronic infection stimulates smooth muscle cell migration and plaque development. Patients undergoing percutaneous coronary angioplasty (PCI) for acute coronary syndrome or stable angina were included in the study. Blood was drawn before PCI, at 6 weeks, and 6 and 12 months after coronary intervention. Eotaxin and C-reactive protein were determined by enzyme-linked immunosorbent assay (ELISA). Antibodies against Candida, C. pneumoniae, cytomegalovirus, Helicobacter pylori, and herpes simplex virus were measured by ELISA or immunofluorescence. Two hundred five consecutive patients undergoing PCI (stable angina, n = 136; acute coronary syndrome, n = 69) and 83 patients with normal coronary arteries were enrolled in the study. Eotaxin concentrations at inclusion were higher in patients with coronary artery disease than in control patients, p = .01, and comparable in patients with stable angina and those with acute coronary syndrome but did not correlate with C-reactive protein. Eotaxin concentrations at inclusion and during follow-up weakly correlated with concentrations of antibodies against C. pneumoniae, H. pylori, and herpes simplex virus but not with concentrations of antibodies against Candida or cytomegalovirus. Eotaxin concentrations and antibody titers against C. pneumoniae significantly increased following angioplasty and remained elevated thereafter. In conclusion, our data demonstrate that eotaxin concentrations are elevated independently from C-reactive protein in patients with coronary artery disease and correlate with antibodies against infectious agents known for chronic infection in humans. 相似文献
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Immature teratoma of the tectum mesencephali with histopathological detection of rudimentary eye anlage in a 3‐year‐old boy: Report of a rare case 下载免费PDF全文
Daniel Dubinski Michel Mittelbronn Gerhard Marquardt Dominique S. Tews Anika Noack Bedjan Behmanesh Volker Seifert Thomas M. Freiman 《Neuropathology》2016,36(6):556-560
Intracranial teratoma is a rare neoplasm derived from omnipotent germinal cells that can contain mesoderm, endoderm and/or ectoderm layer tissue. Histologically teratomas are characterized by abnormal structures like teeth or bone that can be further subdivided into mature and immature according to the presence of incompletely differentiated tissue. Characteristic intracranial teratomas are space‐occupying lesions in the pineal region and often present with hydrocephalic symptoms due to aqueduct stenosis. A 3‐year‐old boy presented with a peracute hemiparesis, fatigue and speech deficit. MRI diagnostics showed a cystic, partially solid, inhomogeneous contrast‐enhancing formation at the top of the tectum mesencephali with consecutive aqueduct compression. The patient underwent a sub‐occipital craniotomy via a supracerebellar approach and complete resection was achieved. The histopathological examination mainly showed mature tissue of ectodermal, mesodermal and endodermal origin. However, small areas of undifferentiated neuroectodermal tissue within an optic vesicle formation were detected, leading to the diagnosis of an immature teratoma. In due course, the patient was discharged in good health without neurological deficits. To our knowledge, optic vesicle‐containing intracranial germ cell tumors are extremely rare. Here we report a unique case with immature neuroectodermal tissue within an optic vesicle formation in an otherwise mature teratoma. 相似文献
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Thomas Krahn Daniel Wibberg Irena Maus Anika Winkler Séverine Bontron Alexander Sczyrba Patrice Nordmann Alfred Pühler Laurent Poirel Andreas Schlüter 《Antimicrobial agents and chemotherapy》2016,60(5):3032-3040
The species Acinetobacter baumannii is one of the most important multidrug-resistant human pathogens. To determine its virulence and antibiotic resistance determinants, the genome of the nosocomial blaNDM-1-positive A. baumannii strain R2090 originating from Egypt was completely sequenced. Genome analysis revealed that strain R2090 is highly related to the community-acquired Australian A. baumannii strain D1279779. The two strains belong to sequence type 267 (ST267). Isolate R2090 harbored the chromosomally integrated transposon Tn125 carrying the carbapenemase gene blaNDM-1 that is not present in the D1279779 genome. To test the transferability of the metallo-β-lactamase (MBL) gene region, the clinical isolate R2090 was mated with the susceptible A. baumannii recipient CIP 70.10, and the carbapenem-resistant derivative R2091 was obtained. Genome sequencing of the R2091 derivative revealed that it had received an approximately 66-kb region comprising the transposon Tn125 embedding the blaNDM-1 gene. This region had integrated into the chromosome of the recipient strain CIP 70.10. From the four known mechanisms for horizontal gene transfer (conjugation, outer membrane vesicle-mediated transfer, transformation, and transduction), conjugation could be ruled out, since strain R2090 lacks any plasmid, and a type IV secretion system is not encoded in its chromosome. However, strain R2090 possesses three putative prophages, two of which were predicted to be complete and therefore functional. Accordingly, it was supposed that the transfer of the resistance gene region from the clinical isolate R2090 to the recipient occurred by general transduction facilitated by one of the prophages present in the R2090 genome. Hence, phage-mediated transduction has to be taken into account for the dissemination of antibiotic resistance genes within the species A. baumannii. 相似文献
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