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991.
Andzelika Najda-Bernatowicz Maja Łebska Andrzej Orzeszko Katarzyna Kopańska Ewa Krzywińska Grażyna Muszyńska Maria Bretner 《Bioorganic & medicinal chemistry》2009,17(4):1573-1578
New derivatives of 4,5,6,7-tetrabromo-1H-1,2,3-benzotriazole (TBBt), 4,5,6,7-tetrabromo-1H-benzimidazole (TBBi), and N-substituted tetrabromophthalimides were synthesized and their effect on the activity of human protein kinase CK2 was examined. The most active were derivatives with N-hydroxypropyl substituents (IC50 in 0.32–0.54 μM range) whereas derivatives of phthalimide were almost ineffective. 相似文献
992.
Heather M. Leslie Maja Schlüter Richard Cudney-Bueno Simon A. Levin 《Ecological Research》2009,24(3):505-519
Key elements of the rapidly expanding field of ecosystem-based management include: (a) understanding connections among social
and ecological systems and (b) developing analytical approaches to inform the necessary trade-offs among ecosystem services
and human activities in coastal and marine areas. To address these needs, we investigate the impacts of multiple economic
sectors on the marine ecosystem and dependent human community in the Gulf of California with an ecological-economic model.
We focus on the spotted rose snapper (Lutjanus guttatus), an economically important species targeted concurrently by the nearshore artisanal fleet, the sportfishing fleet, and by
the industrial shrimp fleet as bycatch. Economic returns to the local community are driven by the artisanal fishery catch
and the number of tourists who engage in the sportsfishery, and these variables are in turn impacted by fish abundance. We
find that the coexistence of the two sectors (and production of both seafood and tourism services) creates stability in key
elements of the coupled systems. When the coupled systems are perturbed by changes in exploitation and climate variability,
the artisanal fishery responds more rapidly and to a greater degree than the sportsfishery to shifts in the fish population.
Our results suggest that vital components of coupled systems may well respond differently to climate variability or other
perturbations, and that management strategies should be developed with this in mind. Models like ours can facilitate the development
and testing of hypotheses about the form and strength of interactions between ecosystems, services, and the human communities
that rely on them.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
H. M. Leslie and M. Schlüter contributed equally to this paper. 相似文献
993.
Jennifer Hirst Daniela A. Sahlender Maja Choma Rita Sinka Michael E. Harbour Michael Parkinson Margaret S. Robinson 《Traffic (Copenhagen, Denmark)》2009,10(11):1696-1710
The GGAs [Golgi-localised, γ-ear containing, ARF (ADP ribosylation factor)-binding proteins] and the AP-1 (adaptor protein-1) complex are both adaptors for clathrin-mediated intracellular trafficking, but their relationship to each other is unclear. We have used two complementary systems, HeLa cells and Drosophila Dmel2 cells, to investigate GGA and AP-1 function. Immunoelectron microscopy of endogenous AP-1 and GGA in Dmel2 cells shows that they are predominantly associated with distinct clathrin-coated structures. Depletion of either GGA or AP-1 by RNAi does not affect the incorporation of the other adaptor into clathrin-coated vesicles (CCVs), and the cargo protein GFP-LERP (green fluorescent protein-lysosomal enzyme receptor protein) is lost from CCVs only when both adaptors are depleted. Similar results were obtained using HeLa cells treated with siRNA to deplete all three GGAs simultaneously. AP-1 was still incorporated into CCVs after GGA depletion and vice versa, and both needed to be depleted for a robust inhibition of receptor-mediated sorting of lysosomal hydrolases. In contrast, downregulation of major histocompatibility complex (MHC) class I by HIV-1 Nef, which requires AP-1, was not affected by a triple GGA knockdown. Thus, our results indicate that the two adaptors can function independently of each other. 相似文献
994.
995.
Julian Little Julian P.T Higgins John P.A Ioannidis David Moher France Gagnon Erik von Elm Muin J Khoury Barbara Cohen George Davey-Smith Jeremy Grimshaw Paul Scheet Marta Gwinn Robin E Williamson Guang Yong Zou Kim Hutchings Candice Y Johnson Valerie Tait Miriam Wiens Jean Golding Cornelia van Duijn John McLaughlin Andrew Paterson George Wells Isabel Fortier Matthew Freedman Maja Zecevic Richard King Claire Infante-Rivard Alex Stewart Nick Birkett 《PLoS medicine》2009,6(2)
996.
Shuzhang Yang Kai Wang Brittany Gregory Wade Berrettini Li-San Wang Hakon Hakonarson Maja Bucan 《PloS one》2009,4(2)
Bipolar disorder (BPD) is a common psychiatric illness with a complex mode of inheritance. Besides traditional linkage and association studies, which require large sample sizes, analysis of common and rare chromosomal copy number variants (CNVs) in extended families may provide novel insights into the genetic susceptibility of complex disorders. Using the Illumina HumanHap550 BeadChip with over 550,000 SNP markers, we genotyped 46 individuals in a three-generation Old Order Amish pedigree with 19 affected (16 BPD and three major depression) and 27 unaffected subjects. Using the PennCNV algorithm, we identified 50 CNV regions that ranged in size from 12 to 885 kb and encompassed at least 10 single nucleotide polymorphisms (SNPs). Of 19 well characterized CNV regions that were available for combined genotype-expression analysis 11 (58%) were associated with expression changes of genes within, partially within or near these CNV regions in fibroblasts or lymphoblastoid cell lines at a nominal P value <0.05. To further investigate the mode of inheritance of CNVs in the large pedigree, we analyzed a set of four CNVs, located at 6q27, 9q21.11, 12p13.31 and 15q11, all of which were enriched in subjects with affective disorders. We additionally show that these variants affect the expression of neuronal genes within or near the rearrangement. Our analysis suggests that family based studies of the combined effect of common and rare CNVs at many loci may represent a useful approach in the genetic analysis of disease susceptibility of mental disorders. 相似文献
997.
Sandra Schordan Eric Schordan Nicole Endlich Maja T. Lindenmeyer Catherine Meyer‐Schwesinger Tobias N. Meyer Jürgen Giebel Clemens D. Cohen Karlhans Endlich Martin H. Maurer 《Proteomics》2009,9(19):4519-4528
Diabetic nephropathy is one of the most common complications of diabetes mellitus and the leading cause of end‐stage renal disease. A reduction in podocyte number has been documented in the kidneys of these patients. To identify the molecular changes in podocytes that are primarily caused by high glucose (HG) concentrations and not by secondary alterations (e.g. glomerular hypertension), we investigated the protein expression profiles in a podocyte cell line under long‐term HG exposure (30 versus 10 mM for 2 wk). Proteins were separated by 2‐DE, and we identified 39 different proteins in 48 spots that were differentially regulated by more than twofold in response to HG concentrations using MALDI‐TOF MS and MASCOT software. These proteins belong to several protein classes, including cytoskeletal proteins and specific annexins (annexins III and VI). Downregulation of annexins III and VI by HG concentrations was confirmed by qRT‐PCR, Western blot, and immunostaining, and was also observed in glomeruli of kidney biopsies from patients with diabetic nephropathy. Our data demonstrate that HG concentrations per se are sufficient to strongly modify the protein expression profile of podocytes, the analysis of which contributes to the identification of novel targets involved in diabetic nephropathy. 相似文献
998.
Vladimir Stevanović Snežana Vukojičić Jasmina Šinžar-Sekulić Maja Lazarević Gordana Tomović Kit Tan 《Plant Systematics and Evolution》2009,283(3-4):219-235
The distributions of 77 Arctic-Alpine species in the Balkans are mapped and the centers of their richness and diversity presented. Within the Dinaric Alps these are Mts Vranica, Durmitor, and Prokletije; in the Scardo-Pindhic mountains, ?arplanina–Rudoka–Korab form a continuous chain; in the Rhodope-Rila mountain system there are Mts Vito?a, Rila, and Pirin; while in the Balkan mountain system there are the West and Central part of Stara planina. A comparison of floristic richness and distribution of Arctic-Alpine flora in relation to altitude, geographical location, and geological substrate is made. Correlations between floristic richness and geographical distance of the Balkan mountains from the two main centers of Arctic-Alpine flora in Central Europe are also provided. 相似文献
999.
Maja A. Tocilescu Uta Fendel Klaus Zwicker Stefan Dröse Stefan Kerscher Ulrich Brandt 《BBA》2010,1797(6-7):625-632
Iron–sulfur cluster N2 of complex I (proton pumping NADH:quinone oxidoreductase) is the immediate electron donor to ubiquinone. At a distance of only ~ 7 Å in the 49-kDa subunit, a highly conserved tyrosine is found at the bottom of the previously characterized quinone binding pocket. To get insight into the function of this residue, we have exchanged it for six different amino acids in complex I from Yarrowia lipolytica. Mitochondrial membranes from all six mutants contained fully assembled complex I that exhibited very low dNADH:ubiquinone oxidoreductase activities with n-decylubiquinone. With the most conservative exchange Y144F, no alteration in the electron paramagnetic resonance spectra of complex I was detectable. Remarkably, high dNADH:ubiquinone oxidoreductase activities were observed with ubiquinones Q1 and Q2 that were coupled to proton pumping. Apparent Km values for Q1 and Q2 were markedly increased and we found pronounced resistance to the complex I inhibitors decyl-quinazoline-amine (DQA) and rotenone. We conclude that Y144 directly binds the head group of ubiquinone, most likely via a hydrogen bond between the aromatic hydroxyl and the ubiquinone carbonyl. This places the substrate in an ideal distance to its electron donor iron–sulfur cluster N2 for efficient electron transfer during the catalytic cycle of complex I. 相似文献
1000.
Mladinov A Rebernjak B Mladinov M Puljević M Pasicek L Puljević D 《Collegium antropologicum》2010,34(4):1373-1378
Aim of this study was to estimate behavioral changes after cardiac surgery (CS). A questionnaire was sent by mail to 74 women and 122 men during May 2004 and the answers were collected by phone. For statistical analysis, the chi2-test was used. A common unhealthy habits before CS were inappropriate diet (80% of all responders), addictions to alcohol (62%) and nicotine (54%). Significantly fewer patients after CS continue with fatty diet (chi2 = 39.069; p < 0.001), smoking (chi2 = 90.286; p < 0.001) and alcohol drinking habits (chi2 = 60.667; p < 0.001). A significant worsening of sexual life (chi2 = 91.533; p < 0.001) and significantly less negative influence of weather changes (chi2 = 20.821; p < 0.001) was found after CS. Men drink more (chi2 = 16.299; p < 0.001) and smoke more (chi2 = 19.635; p < 0.001), have better sexual life (chi2 = 17.317; p < 0.001), fewer sleeping disorders (chi2 = 17.334; p < 0.001) and better oral health (chi2 = 38.632; p < 0.001) than women. These results can be useful for setting up preventive measures for CVD. 相似文献