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31.
The fragmentary remains of a juvenile rhabdodontid ornithopod from the Coal-bearing Complex of the Gosau Group (Lower Campanian, Grünbach syncline) at Muthmannsdorf near Wiener Neustadt, Lower Austria are revised. The material, probably belonging to a single individual, includes a right dentary (lectotype of Iguanodon suessi Bunzel, 1871, designated herein), teeth, a fragmentary parietal, fragments of scapula, ?radius, femur, tibia, two vertebrae (lost) and a manual ungual.The lectotype dentary does not provide clear autapomorphies or sufficient diagnostic features to determine its position within the Rhabdodontidae at generic level. By this “Iguanodon suessi” Bunzel, 1871 and the genus “Mochlodon” Seeley, 1881, to which it was latter referred as type species, cannot be characterized sufficiently by differential diagnosis and these are best considered nomina dubia. Based upon combined character comparisons (mainly postcranial features) the Muthmannsdorf ornithopod is referred herein to Zalmoxes Weishampel, Jianu, Csiki and Norman, 2003, a genus so far known from the late Maastrichtian of Romania. It probably but not evidently represents a yet unnamed species, most closely related to Zalmoxes shqiperorum Weishampel, Jianu, Csiki and Norman, 2003. At the present state of knowledge the Austrian material is not further diagnostic at the species level and kept in open nomenclature as Zalmoxes sp. 相似文献
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Jacob F Ukegjini K Nixdorf S Ford CE Olivier J Caduff R Scurry JP Guertler R Hornung D Mueller R Fink DA Hacker NF Heinzelmann-Schwarz VA 《PloS one》2012,7(2):e31885
Background
Activation of the Wnt signaling pathway is implicated in aberrant cellular proliferation in various cancers. In 40% of endometrioid ovarian cancers, constitutive activation of the pathway is due to oncogenic mutations in β-catenin or other inactivating mutations in key negative regulators. Secreted frizzled-related protein 4 (SFRP4) has been proposed to have inhibitory activity through binding and sequestering Wnt ligands.Methodology/Principal Findings
We performed RT-qPCR and Western-blotting in primary cultures and ovarian cell lines for SFRP4 and its key downstream regulators activated β-catenin, β-catenin and GSK3β. SFRP4 was then examined by immunohistochemistry in a cohort of 721 patients and due to its proposed secretory function, in plasma, presenting the first ELISA for SFRP4. SFRP4 was most highly expressed in tubal epithelium and decreased with malignant transformation, both on RNA and on protein level, where it was even more profound in the membrane fraction (p<0.0001). SFRP4 was expressed on the protein level in all histotypes of ovarian cancer but was decreased from borderline tumors to cancers and with loss of cellular differentiation. Loss of membrane expression was an independent predictor of poor survival in ovarian cancer patients (p = 0.02 unadjusted; p = 0.089 adjusted), which increased the risk of a patient to die from this disease by the factor 1.8.Conclusions/Significance
Our results support a role for SFRP4 as a tumor suppressor gene in ovarian cancers via inhibition of the Wnt signaling pathway. This has not only predictive implications but could also facilitate a therapeutic role using epigenetic targets. 相似文献34.
35.
Londoño D Marques A Hornung RL Cadavid D 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(3):2076-2083
During relapsing fever borreliosis, a high pathogen load in the blood occurs at times of peak bacteremia. Specific IgM Abs are responsible for spirochetal clearance so in absence of B cells there is persistent high-level bacteremia. Previously, we showed that B cell-deficient mice persistently infected with Borrelia turicatae produce high levels of IL-10 and that exogenous IL-10 reduces bacteremia. This suggested that IL-10 helps reduce bacteremia at times of high pathogen load by a B cell-independent mechanism, most likely involving innate immunity. To investigate this possibility, we compared B. turicatae infection in RAG2/IL-10(-/-) and RAG2(-/-) mice. The results showed that IL-10 deficiency resulted in significantly higher bacteremia, higher TNF levels, and early mortality. Examination of the spleen and peripheral blood showed markedly increased apoptosis of immune cells in infected RAG2/IL-10(-/-) mice. Neutralization of TNF reduced apoptosis of leukocytes and splenocytes, increased production of IFN-gamma by NK cells, increased phagocytosis in the spleen, decreased spirochetemia, and rescued mice from early death. Our results indicate that at times of high pathogen load, as during peak bacteremia in relapsing fever borreliosis, IL-10 protects innate immune cells from apoptosis via inhibition of TNF resulting in improved pathogen control. 相似文献
36.
Marion Brodhagen Dimitrios I Tsitsigiannis Ellen Hornung Cornelia Goebel Ivo Feussner Nancy P Keller 《Molecular microbiology》2008,67(2):378-391
In Aspergilli, mycotoxin production and sporulation are governed, in part, by endogenous oxylipins (oxygenated, polyunsaturated fatty acids and metabolites derived therefrom). In Aspergillus nidulans, oxylipins are synthesized by the dioxygenase enzymes PpoA, PpoB and PpoC. Structurally similar oxylipins are synthesized in seeds via the action of lipoxygenase (LOX) enzymes. Previous reports have shown that exogenous application of seed oxylipins to Aspergillus cultures alters sporulation and mycotoxin production. Herein, we explored whether a plant oxylipin biosynthetic gene (ZmLOX3) could substitute functionally for A. nidulans ppo genes. We engineered ZmLOX3 into wild-type A. nidulans, and into a DeltappoAC strain that was reduced in production of oxylipins, conidia and the mycotoxin sterigmatocystin. ZmLOX3 expression increased production of conidia and sterigmatocystin in both backgrounds. We additionally explored whether A. nidulans oxylipins affect seed LOX gene expression during Aspergillus colonization. We observed that peanut seed pnlox2-3 expression was decreased when infected by A. nidulansDeltappo mutants compared with infection by wild type. This result provides genetic evidence that fungal oxylipins are involved in plant LOX gene expression changes, leading to possible alterations in the fungal/host interaction. This report provides the first genetic evidence for reciprocal oxylipin cross-talk in the Aspergillus-seed pathosystem. 相似文献
37.
Hornung T Ishmukhametov R Spetzler D Martin J Frasch WD 《Biochimica et biophysica acta》2008,1777(7-8):579-582
The torque generated by the power stroke of Escherichia coli F(1)-ATPase was determined as a function of the load from measurements of the velocity of the gamma-subunit obtained using a 0.25 micros time resolution and direct measurements of the drag from 45 to 91 nm gold nanorods. This result was compared to values of torque calculated using four different drag models. Although the gamma-subunit was able to rotate with a 20x increase in viscosity, the transition time decreased from 0.4 ms to 5.26 ms. The torque was measured to be 63+/-8 pN nm, independent of the load on the enzyme. 相似文献
38.
Genomic organization and expression of the doublesex-related gene cluster in vertebrates and detection of putative regulatory regions for DMRT1. 总被引:16,自引:0,他引:16
B Brunner U Hornung Z Shan I Nanda M Kondo E Zend-Ajusch T Haaf H H Ropers A Shima M Schmid V M Kalscheuer M Schartl 《Genomics》2001,77(1-2):8-17
Genes related to the Drosophila melanogaster doublesex and Caenorhabditis elegans mab-3 genes are conserved in human. They are identified by a DNA-binding homology motif, the DM domain, and constitute a gene family (DMRTs). Unlike the invertebrate genes, whose role in the sex-determination process is essentially understood, the function of the different vertebrate DMRT genes is not as clear. Evidence has accumulated for the involvement of DMRT1 in male sex determination and differentiation. DMRT2 (known as terra in zebrafish) seems to be a critical factor for somitogenesis. To contribute to a better understanding of the function of this important gene family, we have analyzed DMRT1, DMRT2, and DMRT3 from the genome model organism Fugu rubripes and the medakafish, a complementary model organism for genetics and functional studies. We found conservation of synteny of human chromosome 9 in F. rubripes and an identical gene cluster organization of the DMRTs in both fish. Although expression analysis and gene linkage mapping in medaka exclude a function for any of the three genes in the primary step of male sex determination, comparison of F. rubripes and human sequences uncovered three putative regulatory regions that might have a role in more downstream events of sex determination and human XY sex reversal. 相似文献
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40.
F. Bode K. Baumann R. Kinne C. Hornung R. Maier G. Zimmerschied 《生物化学与生物物理学报:生物膜》1976,433(2):294-310
Pinocytic vesicles, brush border microvilli, lysosomes and basolateral plasma membranes were isolated from rat kidney cortex and their biochemical composition and membrane turnover compared. Pinocytic vesicles are devoid of marker enzymes of brush border microvilli, such as alkaline phosphatase and 5′-nucleotidase, and of lysosomes, such as acid phosphatase and β-glucuronidase. The protein pattern as revealed by polyacrylamide gel electrophoresis differs for all four membranes. Analysis of the phospholipid composition shows that pinocytic vesicles are rich in the negatively charged phospholipid phosphatidylserine and have a low content of sphingomyelin and phosphatidylethanolamine.[14C]guanido-arginine, [3H]fucose and were preferentially incorporated into the pinocytic vesicles. Using a double label technique with leucine also, evidence of a more rapid turnover of the pinocytic vesicle membrane proteins was obtained.The results suggest that pinocytic vesicles are not derived from the brush border microvillous membrane but are independent entities that are newly synthesized during the pinocytic process. 相似文献