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121.
Charlotte E. Konikoff Robert G. Wisotzkey Michael J. Stinchfield Stuart J. Newfeld 《Journal of molecular evolution》2010,70(4):303-312
The canonical Wnt pathway is one of the oldest and most functionally diverse of animal intercellular signaling pathways. Though
much is known about loss-of-function phenotypes for Wnt pathway components in several model organisms, the question of how
this pathway achieved its current repertoire of functions has not been addressed. Our phylogenetic analyses of 11 multigene
families from five species belonging to distinct phyla, as well as additional analyses employing the 12 Drosophila genomes,
suggest frequent gene duplications affecting ligands and receptors as well as co-evolution of new ligand–receptor pairs likely
facilitated the expansion of this pathway’s capabilities. Further, several examples of recent gene loss are visible in Drosophila
when compared to family members in other phyla. By comparison the TGFβ signaling pathway is characterized by ancient gene
duplications of ligands, receptors, and signal transducers with recent duplication events restricted to the vertebrate lineage.
Overall, the data suggest that two distinct molecular evolutionary mechanisms can create a functionally diverse developmental
signaling pathway. These are the recent dynamic generation of new genes and ligand–receptor interactions as seen in the Wnt
pathway and the conservative adaptation of ancient pre-existing genes to new roles as seen in the TGFβ pathway. From a practical
perspective, the former mechanism limits the investigator’s ability to transfer knowledge of specific pathway functions across
species while the latter facilitates knowledge transfer. 相似文献
122.
Yves‐Marie Coïc Charlotte Le Lan Jean‐Michel Neumann Nadège Jamin Françoise Baleux 《Journal of peptide science》2010,16(2):98-104
This work contributes to highlight the benefits of pseudoproline dipeptides introduction in difficult SPPS. We show how a slight modification in the positioning choice conditioned the synthesis achievement of a 54 amino acid long caveolin‐1 peptide encompassing the intramembrane domain. Furthermore, we report a side reaction correlated with the coupling steps and generating truncated fragments with a mass deviation of + 42 Da. Considering the need of structural data for membrane proteins, most of which are considered as prevalent therapeutic targets, chemical synthesis provides an interesting alternative pathway to obtain hydrophobic domains by pushing back the frontiers of conventional RP methods of purification. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
123.
Benoit Visseaux Charlotte Charpentier Gilles Collin Mélanie Bertine Gilles Peytavin Florence Damond Sophie Matheron Eric Lefebvre Fran?oise Brun-Vézinet Diane Descamps ANRS CO HIV- Cohort 《PloS one》2015,10(8)
Background
Maraviroc activity against HIV-2, a virus naturally resistant to different HIV-1 antiretroviral drugs, has been recently demonstrated. The aim of this study was to assess HIV-2 susceptibility to cenicriviroc, a novel, once-daily, dual CCR5 and CCR2 antagonist that has completed Phase 2b development in HIV-1 infection.Methods
Cenicriviroc phenotypic activity has been tested using a PBMC phenotypic susceptibility assay against four R5-, one X4- and one dual-tropic HIV-2 clinical primary isolates. All isolates were obtained by co-cultivation of PHA-activated PBMC from distinct HIV-2-infected CCR5-antagonist-naïve patients included in the French HIV-2 cohort and were previously tested for maraviroc susceptibility using the same protocol. HIV-2 tropism was determined by phenotypic assay using Ghost(3) cell lines.Results
Regarding the 4 R5 HIV-2 clinical isolates tested, effective concentration 50% EC50 for cenicriviroc were 0.03, 0.33, 0.45 and 0.98 nM, similar to those observed with maraviroc: 1.13, 0.58, 0.48 and 0.68 nM, respectively. Maximum percentages of inhibition (MPI) of cenicriviroc were 94, 94, 93 and 98%, similar to those observed with maraviroc (93, 90, 82, 100%, respectively). The dual- and X4-tropic HIV-2 strains were resistant to cenicriviroc with EC50 >1000 nM and MPI at 33% and 4%, respectively.Conclusions
In this first study assessing HIV-2 susceptibility to cenicriviroc, we observed an in vitro activity against HIV-2 R5-tropic strains similar to that observed with maraviroc. Thus, cenicriviroc may offer a once-daily treatment opportunity in the limited therapeutic arsenal for HIV-2. Clinical studies are warranted. 相似文献124.
Methods for surveillance of fetal alcohol syndrome: The fetal alcohol syndrome surveillance network II (FASSNetII) – Arizona,Colorado, New York, 2009 ‐ 2014 下载免费PDF全文
Leslie A. O'Leary Linnette Ortiz April Montgomery Deborah J. Fox Christopher Cunniff Margaret Ruttenber April Breen Sydney Pettygrove Don Klumb Charlotte Druschel Jaime L. Frías Luther K. Robinson Jacquelyn Bertrand Kelly Ferrara Maureen Kelly Suzanne M. Gilboa F. John Meaney for the FASSNetII 《Birth defects research. Part A, Clinical and molecular teratology》2015,103(3):196-202
125.
126.
Charlotte Schou Erik R. Ottosen Hans Jørgen Petersen Fredrik Björkling Scilla Latini Pernille V. Hjarnaa Erik Bramm Lise Binderup 《Bioorganic & medicinal chemistry letters》1997,7(24):616-3100
4-Pyridyl cyanoguanidines with hydrophobic aromatic side chains showed potent antiproliferative activity in the human breast and lung cancer cell lines MCF-7, NYH and H460. In vivo, treatment with N-(6-chlorophenoxyhexyl)-N′-cyano-N″-4-pyridylguanidine (18, 20 mg/kg/day po.), gave a complete remission of tumours in a model of NYH inoculated nude mice. 相似文献
127.
128.
Juliette Gaëtan Sébastien Halary Maxime Millet Cécile Bernard Charlotte Duval Sahima Hamlaoui Amandine Hecquet Muriel Gugger Benjamin Marie Neha Mehta David Moreira Fériel Skouri-Panet Cynthia Travert Elodie Duprat Julie Leloup Karim Benzerara 《Environmental microbiology》2023,25(3):751-765
The formation of intracellular amorphous calcium carbonates (iACC) has been recently observed in a few cultured strains of Microcystis, a potentially toxic bloom-forming cyanobacterium found worldwide in freshwater ecosystems. If iACC-forming Microcystis are abundant within blooms, they may represent a significant amount of particulate Ca. Here, we investigate the significance of iACC biomineralization by Microcystis. First, the presence of iACC-forming Microcystis cells has been detected in several eutrophic lakes, indicating that this phenomenon occurs under environmental conditions. Second, some genotypic (presence/absence of ccyA, a marker gene of iACC biomineralization) and phenotypic (presence/absence of iACC) diversity have been detected within a collection of strains isolated from one single lake. This illustrates that this trait is frequent but also variable within Microcystis even at a single locality. Finally, one-third of publicly available genomes of Microcystis were shown to contain the ccyA gene, revealing a wide geographic and phylogenetic distribution within the genus. Overall, the present work shows that the formation of iACC by Microcystis is common under environmental conditions. While its biological function remains undetermined, this process should be further considered regarding the biology of Microcystis and implications on the Ca geochemical cycle in freshwater environments. 相似文献
129.
Quantitative proteomics suggests decrease in the secretogranin‐1 cerebrospinal fluid levels during the disease course of multiple sclerosis 下载免费PDF全文
Ann C. Kroksveen Jacob D. Jaffe Elise Aasebø Harald Barsnes Yngvild Bjørlykke Diego Franciotta Hasmik Keshishian Kjell‐Morten Myhr Jill A. Opsahl Vincent van Pesch Charlotte E. Teunissen Øivind Torkildsen Rune J. Ulvik Heidrun Vethe Steven A. Carr Frode S. Berven 《Proteomics》2015,15(19):3361-3369
Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS with unknown cause. Proteins with different abundance in the cerebrospinal fluid (CSF) from relapsing‐remitting MS (RRMS) patients and neurological controls could give novel insight to the MS pathogenesis and be used to improve diagnosis, predict prognosis and disease course, and guide in therapy decisions. We combined iTRAQ labeling and Orbitrap mass spectrometry to discover proteins with different CSF abundance between six RRMS patients and 18 neurological disease controls. From 777 quantified proteins seven were selected as biomarker candidates, namely chitinase‐3‐like protein 1, secretogranin‐1 (Sg1), cerebellin‐1, neuroserpin, cell surface glycoprotein MUC18, testican‐2 and glutamate receptor 4. An independent sample set of 13 early‐MS patients, 13 RRMS patients and 13 neurological controls was used in a multiple reaction monitoring verification study. We found the intracellular calcium binding protein Sg1 to be increased in early‐MS patients compared to RRMS and neurological controls. Sg1 should be included in further studies to elucidate its role in the early phases of MS pathogenesis and its potential as a biomarker for this disease. 相似文献
130.
Large morphological sex differences in the vertebrate brain were initially identified in song control nuclei of oscines. Besides gross differences between volumes of nuclei in males and females, sex differences also concern the size and dendritic arborization of neurons and various neurochemical markers, such as the calcium-binding protein parvalbumin (PV). Perineuronal nets (PNN) of the extracellular matrix are aggregates of different compounds, mainly chondroitin sulfate proteoglycans, that surround subsets of neurons, often expressing PV. PNN develop in zebra finches song control nuclei around the end of the sensitive period for song learning and tutor deprivation, known to delay the end of the song learning sensitive period, decreases the numbers of PNN in HVC. We demonstrate here the existence in zebra finches of a major sex difference (males > females) affecting the number of PNN (especially those surrounding PV-positive cells) in HVC and to a smaller extent the robust nucleus of the arcopallium, RA, the two main nuclei controlling song production. These differences were not present in Area X and LMAN, the lateral magnocellular nucleus of the anterior nidopallium. A dense expression of material immunoreactive for chondroitin sulfate was also detected in several nuclei of the auditory and visual pathways. This material was often organized in perineuronal rings but quantification of these PNN did not reveal any sex difference with the exception that the percentage of PNN surrounding PV-ir cells in the dorsal lateral mesencephalic nucleus, MLd, was larger in females than in males, a sex difference in the opposite direction compared to what is seen in HVC and RA. These data confirm and extend previous studies demonstrating the sex difference affecting PNN in HVC-RA by showing that this sex difference is anatomically specific and does not concern visual or auditory pathways. 相似文献