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971.
Booth AJ Grabauskiene S Wood SC Lu G Burrell BE Bishop DK 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(11):5764-5771
IL-6 mediates numerous immunologic effects relevant to transplant rejection; however, its specific contributions to these processes are not fully understood. To this end, we neutralized IL-6 in settings of acute cardiac allograft rejection associated with either CD8(+) or CD4(+) cell-dominant responses. In a setting of CD8(+) cell-dominant graft rejection, IL-6 neutralization delayed the onset of acute rejection while decreasing graft infiltrate and inverting anti-graft Th1/Th2 priming dominance in recipients. IL-6 neutralization markedly prolonged graft survival in the setting of CD4(+) cell-mediated acute rejection and was associated with decreased graft infiltrate, altered Th1 responses, and reduced serum alloantibody. Furthermore, in CD4(+) cell-dominated rejection, IL-6 neutralization was effective when anti-IL-6 administration was delayed by as many as 6 d posttransplant. Finally, IL-6-deficient graft recipients were protected from CD4(+) cell-dominant responses, suggesting that IL-6 production by graft recipients, rather than grafts, is necessary for this type of rejection. Collectively, these observations define IL-6 as a critical promoter of graft infiltration and a shaper of T cell lineage development in cardiac graft rejection. In light of these findings, the utility of therapeutics targeting IL-6 should be considered for preventing cardiac allograft rejection. 相似文献
972.
Domestication affects behavioral and vocal responses, involved in communication with humans; in particular, those that attract human attention. In this study, we found that silver foxes of Tame strain, experimentally domesticated for a few tenses of generation, displayed bursts of vocal activity during the first minute after appearance of an unfamiliar human, that faded quickly during the remaining time of the test, when the experimenter stayed passively before the cage. Distinctively, foxes of Aggressive strain, artificially selected for tenses of generation for aggressive behavior toward humans, and the control group of Unselected for behavior silver foxes kept steady levels of vocal activity for the duration of the tests. We found also that Aggressive foxes vocalized for a larger proportion of time than Unselected foxes for all 5 min of the test. We discuss the obtained data in relation to proposal effects of domestication on mechanisms directed to involving people into human-animal interactions and structural similarity between human laughter and vocalization of Tame foxes. 相似文献
973.
Sidorova NN Kurchashova SY Yarahmedov TY Ziganshin RH Kuimov AN 《Molecular and cellular biochemistry》2011,352(1-2):231-238
Mannose-binding lectin was identified as a substrate of tankyrase 2, an enzyme that catalyzes poly(ADP-ribosyl)ation. The endogenous tankyrase 2 was isolated out of cytoplasm of human embryonic kidney cells. It was bound to a soluble complex of at least two other proteins; they were identified using specific antibodies and other approaches as keratin 1 and mannose-binding lectin. Using immunoblot analysis and radioactive labeling, we detected tankyrase-2-dependent poly(ADP-ribosyl)ation of mannose-binding lectin. In the presence of NAD(+), the complex of keratin 1 and lectin was dissociated, what was recorded during elution of its separate components out of affinity columns and by decrease of their apparent molecular masses during gel-filtration. Tankyrase 2 also inhibited the carbohydrate-binding function of the lectin. The latter effect was observed using mannose-binding lectin out of human serum, which is free from keratin 1. As a result of tankyrase-2 activity, the lectin lost its affinity to mannan-agarose. The discovery of this new biochemical mechanism justifies further analysis of its physiological and medical significance. 相似文献
974.
Boyko AS Konnova SA Fedonenko YP Zdorovenko EL Smol'kina ON Kachala VV Ignatov VV 《Microbiological research》2011,166(7):585-593
Azospirillum brasilense SR55, isolated from the rhizosphere of Triticum durum, was classified as serogroup II on the basis of serological tests. Such serogroup affiliation is uncharacteristic of wheat-associated Azospirillum species. The lipid A of A. brasilense SR55 lipopolysaccharide contained 3-hydroxytetradecanoic, 3-hydroxyhexadecanoic, hexadecanoic and octadecenoic fatty acids. The structure of the lipopolysaccharide's O polysaccharide was established, with the branched octasaccharide repeating unit being represented by l-rhamnose, l-3-O-Me-rhamnose, d-galactose and d-glucuronic acid. The SR55 lipopolysaccharide induced deformations of wheat root hairs. The lipopolysaccharide was not involved in bacterial cell aggregation, but its use to pretreat wheat roots was conducive to cell adsorption. This study shows that Azospirillum bacteria can utilise their own lipopolysaccharide as a carbon source, which may give them an advantage in competitive natural environments. 相似文献
975.
976.
A direct HPTLC assay was developed for the determination of total curcuminoids and three individual curcuminoids, curcumin, demethoxycurcumin and bisdemethoxycurcumin. In addition, a new procedure was developed to separate and quantitative the free radical-scavenging activity of individual compounds from the rhizome of Curcuma longa L. (Zingiberaceae) based on the combination of HPTLC with a diode array detector (DAD) and post chromatographic DPPH(*) radical derivatisation. It was established that both individual curcuminoids and the extract of C. longa were capable of scavenging DPPH(*) radicals. From the estimated ID(50) values, it can be seen that the order of activity was curcumin > demethoxycurcumin > bisdemethoxycurcumin > ascorbic acid. However, the ID(50) values of curcuminoids were not significantly different. The data indicates the presence of a synergistic mechanism of antiradical activity of curcuminoids. 相似文献
977.
Stevan Pecic Svetlana Pakhomova Marcia E. Newcomer Christophe Morisseau Bruce D. Hammock Zhengxiang Zhu Alison Rinderspacher Shi-Xian Deng 《Bioorganic & medicinal chemistry letters》2013,23(2):417-421
A series of potent amide non-urea inhibitors of soluble epoxide hydrolase (sEH) is disclosed. The inhibition of soluble epoxide hydrolase leads to elevated levels of epoxyeicosatrienoic acids (EETs), and thus inhibitors of sEH represent one of a novel approach to the development of vasodilatory and anti-inflammatory drugs. Structure–activities studies guided optimization of a lead compound, identified through high-throughput screening, gave rise to sub-nanomolar inhibitors of human sEH with stability in human liver microsomal assay suitable for preclinical development. 相似文献
978.
Svetlana A. Yatsenko Patricia Hixson Erin K. Roney Daryl A. Scott Christian P. Schaaf Yu-tze Ng Robbin Palmer Richard B. Fisher Ankita Patel Sau Wai Cheung James R. Lupski 《Human genetics》2012,131(12):1895-1910
Constitutional deletions of distal 9q34 encompassing the EHMT1 (euchromatic histone methyltransferase 1) gene, or loss-of-function point mutations in EHMT1, are associated with the 9q34.3 microdeletion syndrome, also known as Kleefstra syndrome [MIM#610253]. We now report further evidence for genomic instability of the subtelomeric 9q34.3 region as evidenced by copy number gains of this genomic interval that include duplications, triplications, derivative chromosomes and complex rearrangements. Comparisons between the observed shared clinical features and molecular analyses in 20 subjects suggest that increased dosage of EHMT1 may be responsible for the neurodevelopmental impairment, speech delay, and autism spectrum disorders revealing the dosage sensitivity of yet another chromatin remodeling protein in human disease. Five patients had 9q34 genomic abnormalities resulting in complex deletion–duplication or duplication–triplication rearrangements; such complex triplications were also observed in six other subtelomeric intervals. Based on the specific structure of these complex genomic rearrangements (CGR) a DNA replication mechanism is proposed confirming recent findings in Caenorhabditis elegans telomere healing. The end-replication challenges of subtelomeric genomic intervals may make them particularly prone to rearrangements generated by errors in DNA replication. 相似文献
979.
Conservation status of freshwater mussels in Europe: state of the art and future challenges 下载免费PDF全文
Manuel Lopes‐Lima David C. Aldridge Rafael Araujo Jakob Bergengren Yulia Bespalaya Erika Bódis Lyubov Burlakova Dirk Van Damme Karel Douda Elsa Froufe Dilian Georgiev Clemens Gumpinger Alexander Karatayev Ümit Kebapçi Ian Killeen Jasna Lajtner Bjørn M. Larsen Rosaria Lauceri Anastasios Legakis Sabela Lois Stefan Lundberg Evelyn Moorkens Gregory Motte Karl‐Otto Nagel Paz Ondina Adolfo Outeiro Momir Paunovic Vincent Prié Ted von Proschwitz Nicoletta Riccardi Mudīte Rudzīte Māris Rudzītis Christian Scheder Mary Seddon Hülya Şereflişan Vladica Simić Svetlana Sokolova Katharina Stoeckl Jouni Taskinen Amílcar Teixeira Frankie Thielen Teodora Trichkova Simone Varandas Heinrich Vicentini Katarzyna Zajac Tadeusz Zajac Stamatis Zogaris 《Biological reviews of the Cambridge Philosophical Society》2017,92(1):572-607
Freshwater mussels of the Order Unionida provide important ecosystem functions and services, yet many of their populations are in decline. We comprehensively review the status of the 16 currently recognized species in Europe, collating for the first time their life‐history traits, distribution, conservation status, habitat preferences, and main threats in order to suggest future management actions. In northern, central, and eastern Europe, a relatively homogeneous species composition is found in most basins. In southern Europe, despite the lower species richness, spatially restricted species make these basins a high conservation priority. Information on freshwater mussels in Europe is unevenly distributed with considerable differences in data quality and quantity among countries and species. To make conservation more effective in the future, we suggest greater international cooperation using standardized protocols and methods to monitor and manage European freshwater mussel diversity. Such an approach will not only help conserve this vulnerable group but also, through the protection of these important organisms, will offer wider benefits to freshwater ecosystems. 相似文献
980.