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91.
Galli U Oliaro-Bosso S Taramino S Venegoni S Pastore E Tron GC Balliano G Viola F Sorba G 《Bioorganic & medicinal chemistry letters》2007,17(1):220-224
New dimethylamino truncated squalene ether derivatives containing a different aromatic moiety (phenyl, naphthyl, and biphenyl) or a simple alkyl (n-hexylic) group were synthesized as inhibitors of the oxidosqualene cyclase (OSC) and of the sterol biosynthetic pathway. The activity against human OSC was compared with the activity against the OSCs of pathogenic organisms such as Pneumocystis carinii and Trypanosoma cruzi. The phenyl derivative was the most potent inhibitor of T. cruzi OSC. 相似文献
92.
Benfatti F Cardillo G Fabbroni S Galzerano P Gentilucci L Juris R Tolomelli A Baiula M Spartà A Spampinato S 《Bioorganic & medicinal chemistry》2007,15(23):7380-7390
Small constrained non-peptidic molecules consisting of a polyfunctionalized rigid core, carrying appendages corresponding to arginine and aspartic acid side chains, have been recently reported to be promising for drug development. In this work, the 5,6-dihydropyridin-2-one was envisaged as a scaffold to turn into potential integrin ligands, introducing a carboxylic acid and a basic appendage. The synthesis and the antiadhesion activity of a small library of peptidomimetics capable to recognize alpha(v)beta(3) and alpha(5)beta(1) integrins has been herein reported. 相似文献
93.
94.
Maize histone deacetylase hda101 is involved in plant development, gene transcription, and sequence-specific modulation of histone modification of genes and repeats 总被引:1,自引:0,他引:1 下载免费PDF全文
Rossi V Locatelli S Varotto S Donn G Pirona R Henderson DA Hartings H Motto M 《The Plant cell》2007,19(4):1145-1162
95.
Vittorini S Storti S Parri MS Cerillo AG Clerico A 《Molecular medicine (Cambridge, Mass.)》2007,13(1-2):105-111
In animal models of conotruncal heart defects, an abnormal calcium sensitivity of the contractile apparatus and a depressed L-type calcium current have been described. Sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA) is a membrane protein that catalyzes the ATP-dependent transport of Ca(2+) from the cytosol to the SR. The activity of SERCA is inhibited by phospholamban (PLN) and sarcolipin (SLN), and all these proteins participate in maintaining the normal intracellular calcium handling. Ryanodine receptors (RyRs) are the major SR calcium-release channels required for excitation-contraction coupling in skeletal and cardiac muscle. Our objective was to evaluate SERCA2a (i.e., the SERCA cardiac isoform), PLN, SLN, and RyR2 (i.e., the RyR isoform enriched in the heart) gene expression in myocardial tissue of patients affected by tetralogy of Fallot (TOF), a conotruncal heart defect. The gene expression of target genes was assessed semiquantitatively by RT-PCR using the calsequestrin (CASQ, a housekeeping gene) RNA as internal standard in the atrial myocardium of 23 pediatric patients undergoing surgical correction of TOF, in 10 age-matched patients with ventricular septal defect (VSD) and in 13 age-matched children with atrial septal defect (ASD). We observed a significantly lower expression of PLN and SLN in TOF patients, while there was no difference between the expression of SERCA2a and RyR2 in TOF and VSD. These data suggest a complex mechanism aimed to enhance the intracellular Ca(2+) reserve in children affected by tetralogy of Fallot. 相似文献
96.
Reinertson RC Nelson VA Aunon SM Schlegel TT Lindgren KN Kerstman EL Arya M Paloski WH 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2007,14(1):P9-13
The NASA artificial gravity-bed rest pilot study (AGPS) was designed to investigate the efficacy of daily exposure to a +Gz acceleration gradient for counteracting the physiologic decrements induced by prolonged bed rest. Test subjects were continuously monitored by a physician for signs and symptoms of pre-syncope, motion sickness, and arrhythmias while on the centrifuge. In this article, we have summarized the medical monitoring observations that were made during the AGPS and included an assessment of the relative usefulness of the information provided by the various monitoring tools in making a decision to terminate a centrifuge spin. 相似文献
97.
Multi‐scale habitat modification by coexisting ecosystem engineers drives spatial separation of macrobenthic functional groups 下载免费PDF全文
Serena Donadi Tjisse van der Heide Theunis Piersma Els M. van der Zee Ellen J. Weerman Johan van de Koppel Han Olff Clare Devine Udhi E. Hernawan Myra Boers Linda Planthof Britas Klemens Eriksson 《Oikos》2015,124(11):1502-1510
By changing habitat conditions, ecosystem engineers increase niche diversity and have profound effects on the distribution and abundances of other organisms. Although many ecosystems contain several engineering species, it is still unclear how the coexistence of multiple engineers affects the physical habitat and the structure of the community on a landscape scale. Here, we investigated through a large‐scale field manipulation how three coexisting engineers on intertidal flats (cockles Cerastoderma edule; lugworms Arenicola marina; blue mussels Mytilus edulis) influence the functional composition of the local macrobenthic community and what the consequences are at the landscape level. By using biological trait analysis (BTA), we show that on the local scale biogenic changes in sediment accumulation and organic matter content translated into specific shifts in the distribution of functional traits within the community. At a landscape scale, the co‐occurrence of multiple ecosystem engineers resulted in the spatial separation of different functional groups, i.e. different functional groups dominated unique complementary habitats. Our results emphasize the role of co‐occurring multiple engineers in shaping natural communities, thus contributing to a better knowledge of community assembly rules. This understanding can profitably be used to improve ecosystem‐based management and conservation actions. 相似文献
98.
Xiaoyan Lin Lucy Thorne Zhinan Jin Loubna A. Hammad Serena Li Jerome Deval Ian G. Goodfellow C. Cheng Kao 《Nucleic acids research》2015,43(1):446-460
The replication enzyme of RNA viruses must preferentially recognize their RNAs in an environment that contains an abundance of cellular RNAs. The factors responsible for specific RNA recognition are not well understood, in part because viral RNA synthesis takes place within enzyme complexes associated with modified cellular membrane compartments. Recombinant RNA-dependent RNA polymerases (RdRps) from the human norovirus and the murine norovirus (MNV) were found to preferentially recognize RNA segments that contain the promoter and a short template sequence for subgenomic RNA synthesis. Both the promoter and template sequence contribute to stable RdRp binding, accurate initiation of the subgenomic RNAs and efficient RNA synthesis. Using a method that combines RNA crosslinking and mass spectrometry, residues near the template channel of the MNV RdRp were found to contact the hairpin RNA motif. Mutations in the hairpin contact site in the MNV RdRp reduced MNV replication and virus production in cells. This work demonstrates that the specific recognition of the norovirus subgenomic promoter is through binding by the viral RdRp. 相似文献
99.
100.
Serena C. Hedgepeth M. Iveth Garcia Larry E. Wagner II Ana M. Rodriguez Sree V. Chintapalli Russell R. Snyder Gary D. V. Hankins Beric R. Henderson Kirsty M. Brodie David I. Yule Damian B. van Rossum Darren Boehning 《The Journal of biological chemistry》2015,290(11):7304-7313
The inositol 1,4,5-trisphosphate receptor (IP3R) is a ubiquitously expressed endoplasmic reticulum (ER)-resident calcium channel. Calcium release mediated by IP3Rs influences many signaling pathways, including those regulating apoptosis. IP3R activity is regulated by protein-protein interactions, including binding to proto-oncogenes and tumor suppressors to regulate cell death. Here we show that the IP3R binds to the tumor suppressor BRCA1. BRCA1 binding directly sensitizes the IP3R to its ligand, IP3. BRCA1 is recruited to the ER during apoptosis in an IP3R-dependent manner, and, in addition, a pool of BRCA1 protein is constitutively associated with the ER under non-apoptotic conditions. This is likely mediated by a novel lipid binding activity of the first BRCA1 C terminus domain of BRCA1. These findings provide a mechanistic explanation by which BRCA1 can act as a proapoptotic protein. 相似文献