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101.
102.
Differential transmission of human immunodeficiency virus type 1 by distinct subsets of effector dendritic cells 总被引:6,自引:0,他引:6
Sanders RW de Jong EC Baldwin CE Schuitemaker JH Kapsenberg ML Berkhout B 《Journal of virology》2002,76(15):7812-7821
Dendritic cells (DC) support human immunodeficiency virus type 1 (HIV-1) transmission by capture of the virus particle in the mucosa and subsequent transport to the draining lymph node, where HIV-1 is presented to CD4(+) Th cells. Virus transmission involves a high-affinity interaction between the DC-specific surface molecule DC-SIGN and the viral envelope glycoprotein gp120 and subsequent internalization of the virus, which remains infectious. The mechanism of viral transmission from DC to T cells is currently unknown. Sentinel immature DC (iDC) develop into Th1-promoting effector DC1 or Th2-promoting DC2, depending on the activation signals. We studied the ability of these effector DC subsets to support HIV-1 transmission in vitro. Compared with iDC, virus transmission is greatly upregulated for the DC1 subset, whereas DC2 cells are inactive. Increased transmission by DC1 correlates with increased expression of ICAM-1, and blocking studies confirm that ICAM-1 expression on DC is important for HIV transmission. The ICAM-1-LFA-1 interaction is known to be important for immunological cross talk between DC and T cells, and our results indicate that this cell-cell contact is exploited by HIV-1 for efficient transmission. 相似文献
103.
Priya A. Debisarun Katharina L. Gssling Ozlem Bulut Gizem Kilic Martijn Zoodsma Zhaoli Liu Marina Oldenburg Nadine Rüchel Bowen Zhang Cheng-Jian Xu Patrick Struycken Valerie A. C. M. Koeken Jorge Domínguez-Andrs Simone J. C. F. M. Moorlag Esther Taks Philipp N. Ostermann Lisa Müller Heiner Schaal Ortwin Adams Arndt Borkhardt Jaap ten Oever Reinout van Crevel Yang Li Mihai G. Netea 《PLoS pathogens》2021,17(10)
104.
Serena Bugoni Valentina Merlini Alessio Porta Giuseppe Zanoni Giovanni Vidari 《化学与生物多样性》2014,11(10):1540-1553
A novel enantioselective divergent route to 13‐alkyl derivatives of α‐ and γ‐ionone, important components of perfumes and fragrances, is reported. This relatively short and convenient methodology takes advantage of the use of a common intermediate, easily obtained from highly enantiomerically enriched (S)‐α‐ionone, which avoids the separate installation of the butenone side chain at C(6) for each analog. Olfactory evaluation of synthesized compounds reconfirmed the influence of the hydrophobic interactions of alkyl substituents at C(5) with olfactory receptors (ORs) in the chemoreception of ionones, and suggested that a synperiplanar orientation of C(13) and the lateral chain is the better geometry fitting OR's cavity. 相似文献
105.
Thomas Jans Erika Graf Christian Jacob Ulrike Zwanzger Silke Groß-Lesch Swantje Matthies Evgeniy Perlov Klaus Hennighausen Melanie Jung Michael Rösler Monika Schulte-Altedorneburg Alexander von Gontard Susann Hänig Esther Sobanski Barbara Alm Luise Poustka Lucia Bliznak Michael Colla Laura Gentschow Roland Burghardt Harriet Salbach-Andrae Katja Becker Martin Holtmann Christine Freitag Andreas Warnke Alexandra Philipsen 《Attention deficit and hyperactivity disorders》2013,5(1):29-40
106.
107.
F. González M. Esther Fárez-Vidal J.M. Arias E. Montoya 《Journal of applied microbiology》1994,77(5):567-573
F. GONZÁLEZ, M.E. FÁREZ-VIDAL, J.M. ARIAS AND E. MONTOYA. 1994. Acid phosphatase and alkaline phosphatase from vegetative cells of Myxococcus coralloides D were purified by two chromatographic steps. The molecular weights were estimated by gel filtration and SDS-PAGE. Optimum pH, stability, optimum temperature and thermal inactivation studies were made for both enzymes. EDTA and other chelating agents inhibited alkaline but not acid activity. Mg2+ activated the alkaline phosphatase, while the acid phosphatase was inhibited by fluoride. Both enzymes degraded a number of phosphomonoesters, but were unable to hydrolyse either polyphosphates or cAMP. The K m values of the acid and alkaline phosphatases for p -nitrophenylphosphate were 5.0 times 10-3 mol ***l-1 and 1.5 times 10-3 mol l-1 , respectively. 相似文献
108.
F-box proteins everywhere 总被引:2,自引:0,他引:2
Lechner E Achard P Vansiri A Potuschak T Genschik P 《Current opinion in plant biology》2006,9(6):631-638
The ubiquitin proteasome system is a key regulator of many biological processes in all eukaryotes. This mechanism employs several types of enzymes, the most important of which are the ubiquitin E3 ligases that catalyse the attachment of polyubiquitin chains to target proteins for their subsequent degradation by the 26S proteasome. Among the E3 families, the SCF is the best understood; it consists of a multi-protein complex in which the F-box protein plays a crucial role by recruiting the target substrate. Strikingly, nearly 700 F-box proteins have been predicted in Arabidopsis, suggesting that plants have the capacity to assemble a multitude of SCF complexes, possibly controlling the stability of hundreds of substrates involved in a plethora of biological processes. Interestingly, viruses and even pathogenic bacteria have also found ways to hijack the plant SCF and to reprogram it for their own purposes. 相似文献
109.
Hart S Fischer OM Prenzel N Zwick-Wallasch E Schneider M Hennighausen L Ullrich A 《Biological chemistry》2005,386(9):845-855
The epidermal growth factor receptor (EGFR) plays a key role in the regulation of important cellular processes under normal and pathophysiological conditions such as cancer. In human mammary carcinomas the EGFR is involved in regulating cell growth, survival, migration and metastasis and its activation correlates with the lack of response in hormone therapy. Here, we demonstrate in oestrogen receptor-positive and -negative human breast cancer cells and primary mammary epithelial cells a cross-communication between G protein-coupled receptors (GPCRs) and the EGFR. We present evidence that specific inhibition of ADAM15 or TACE blocks GPCR-induced and proHB-EGF-mediated EGFR tyrosine phosphorylation, downstream mitogenic signalling and cell migration. Notably, activation of the PI3K downstream mediator PKB/Akt by GPCR ligands involves the activity of sphingosine kinase (SPHK) and is independent of EGFR signal transactivation. We conclude that GPCR-induced chemotaxis of breast cancer cells is mediated by EGFR-dependent and -independent signalling pathways, with both parallel pathways having to act in concert to achieve a complete migratory response. 相似文献
110.
Many olfactory receptor neurons use a cAMP-dependent transduction mechanism to transduce odorants into depolarizations. This signaling cascade is characterized by a sequence of two currents: a cation current through cyclic nucleotide-gated channels followed by a chloride current through calcium-activated chloride channels. To date, it is not possible to interfere with these generator channels under physiological conditions with potent and specific blockers. In this study we identified the styryl dye FM1-43 as a potent blocker of native olfactory cyclic nucleotide-gated channels. Furthermore, we characterized this substance to stain olfactory receptor neurons that are endowed with cAMP-dependent transduction. This allows optical differentiation and pharmacological interference with olfactory receptor neurons at the level of the signal transduction. 相似文献