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51.
Nocentini S Reginensi D Garcia S Carulla P Moreno-Flores MT Wandosell F Trepat X Bribian A del Río JA 《Cellular and molecular life sciences : CMLS》2012,69(10):1689-1703
Newly generated olfactory receptor axons grow from the peripheral to the central nervous system aided by olfactory ensheathing
cells (OECs). Thus, OEC transplantation has emerged as a promising therapy for spinal cord injuries and for other neural diseases.
However, these cells do not present a uniform population, but instead a functionally heterogeneous population that exhibits
a variety of responses including adhesion, repulsion, and crossover during cell–cell and cell–matrix interactions. Some studies
report that the migratory properties of OECs are compromised by inhibitory molecules and potentiated by chemical gradients.
Here, we demonstrated that rodent OECs express all the components of the Nogo receptor complex and that their migration is
blocked by myelin. Next, we used cell tracking and traction force microscopy to analyze OEC migration and its mechanical properties
over myelin. Our data relate the decrease of traction force of OEC with lower migratory capacity over myelin, which correlates
with changes in the F-actin cytoskeleton and focal adhesion distribution. Lastly, OEC traction force and migratory capacity
is enhanced after cell incubation with the Nogo receptor inhibitor NEP1-40. 相似文献
52.
Fourteen freshwater ostracod species collected from 24 springs in Nevada, Idaho, and Oregon between 1991 and 1994 were classified. Their ecology, based on major water parameters (i.e., temperature, dissolved oxygen, pH, conductivity), and biogeographical distribution in North America were studied. Among these 14 species, 9 ( Ilyocypris bradyi , I. gibba , Darwinula stevensoni , Candona candida , Heterocypris incongruens , Herpetocypris reptans , H. chevreuxi , Prionocypris canadensis , P. longiforma ) are new records for Nevadas ostracod fauna, while 3 ( H. reptans , P. canadensis , and Cypria turneri ) are new species for Oregon. H. reptans , P. canadensis , and Heterocypris salina are also recorded as new for the ostracod literature of Idaho. Scottia pseudobrowniana , collected from Nevada, is a new ostracod species for the United States. The occurrence of 5 Holarctic species in the northern Great Basin area may suggest a possible historical relationship with the European ostracod fauna. 相似文献
53.
Bass AJ Lawrence MS Brace LE Ramos AH Drier Y Cibulskis K Sougnez C Voet D Saksena G Sivachenko A Jing R Parkin M Pugh T Verhaak RG Stransky N Boutin AT Barretina J Solit DB Vakiani E Shao W Mishina Y Warmuth M Jimenez J Chiang DY Signoretti S Kaelin WG Spardy N Hahn WC Hoshida Y Ogino S Depinho RA Chin L Garraway LA Fuchs CS Baselga J Tabernero J Gabriel S Lander ES Getz G Meyerson M 《Nature genetics》2011,43(10):964-968
Prior studies have identified recurrent oncogenic mutations in colorectal adenocarcinoma and have surveyed exons of protein-coding genes for mutations in 11 affected individuals. Here we report whole-genome sequencing from nine individuals with colorectal cancer, including primary colorectal tumors and matched adjacent non-tumor tissues, at an average of 30.7× and 31.9× coverage, respectively. We identify an average of 75 somatic rearrangements per tumor, including complex networks of translocations between pairs of chromosomes. Eleven rearrangements encode predicted in-frame fusion proteins, including a fusion of VTI1A and TCF7L2 found in 3 out of 97 colorectal cancers. Although TCF7L2 encodes TCF4, which cooperates with β-catenin in colorectal carcinogenesis, the fusion lacks the TCF4 β-catenin-binding domain. We found a colorectal carcinoma cell line harboring the fusion gene to be dependent on VTI1A-TCF7L2 for anchorage-independent growth using RNA interference-mediated knockdown. This study shows previously unidentified levels of genomic rearrangements in colorectal carcinoma that can lead to essential gene fusions and other oncogenic events. 相似文献
54.
Detecting and Predicting Economic Accelerations,Recessions, and Normal Growth Periods in Real‐Time 下载免费PDF全文
Christian R. Proaño 《Journal of forecasting》2017,36(1):26-42
The dichotomous characterization of the business cycle in recessions and expansions has been central in the literature over the last 50 years. However, there are various reasons to question the adequacy of this dichotomous, recession/expansion approach for our understanding of the business cycle dynamics, as well as for the prediction of future business cycle developments. In this context, the contribution of this paper to the literature is twofold. First, since a positive rate of growth at the level of economic activity can be considered as the normal scenario in modern economies due to both population and technological growth, it proposes a new non‐parametric algorithm for the detection and dating of economic acceleration periods, trend or normal growth periods, and economic recessions. Second, it uses an ordered probit framework for the estimation and forecasting of these three business cycle phases, applying an automatized model selection approach using monthly macroeconomic and financial data on the German economy. The empirical results show that this approach has superior out‐of‐sample properties under real‐time conditions compared to alternative probit models specified individually for the prediction of recessions and/or economic accelerations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
55.
Rafaela Lacerda Juliane Menezes Luísa Romão 《Cellular and molecular life sciences : CMLS》2017,74(9):1659-1680
The scanning model for eukaryotic mRNA translation initiation states that the small ribosomal subunit, along with initiation factors, binds at the cap structure at the 5′ end of the mRNA and scans the 5′ untranslated region (5′UTR) until an initiation codon is found. However, under conditions that impair canonical cap-dependent translation, the synthesis of some proteins is kept by alternative mechanisms that are required for cell survival and stress recovery. Alternative modes of translation initiation include cap- and/or scanning-independent mechanisms of ribosomal recruitment. In most cap-independent translation initiation events there is a direct recruitment of the 40S ribosome into a position upstream, or directly at, the initiation codon via a specific internal ribosome entry site (IRES) element in the 5′UTR. Yet, in some cellular mRNAs, a different translation initiation mechanism that is neither cap- nor IRES-dependent seems to occur through a special RNA structure called cap-independent translational enhancer (CITE). Recent evidence uncovered a distinct mechanism through which mRNAs containing N 6-methyladenosine (m6A) residues in their 5′UTR directly bind eukaryotic initiation factor 3 (eIF3) and the 40S ribosomal subunit in order to initiate translation in the absence of the cap-binding proteins. This review focuses on the important role of cap-independent translation mechanisms in human cells and how these alternative mechanisms can either act individually or cooperate with other cis-acting RNA regulons to orchestrate specific translational responses triggered upon several cellular stress states, and diseases such as cancer. Elucidation of these non-canonical mechanisms reveals the complexity of translational control and points out their potential as prospective novel therapeutic targets. 相似文献
56.
S. A. Catanzaro-Guimarães N. Alle E. S. Lopes 《Cellular and molecular life sciences : CMLS》1971,27(12):1400-1401
Résumé Utilisant la méthode cytophotométrique on a observé l'accroissement du glycogène et la réduction de ARN dans le foie de souris soumises au traitement toxique par l'uréthane. 相似文献
57.
Zusammenfassung Werden Lunge und Milz von Yoshida-Sarkomaratten bereits fünf Tage nach der Tumortransplantation entnommen und in normale Ratten implantiert, so zeigt der Umstand, dass sich aus diesen Organen Tumoren entwickeln,in situ belassen aber keine Metastasenknötchen bilden, dass dies auf andere Bedingungen als solche, die mit der Lebensfähigkeit der Zellen zusammenhängen, zurückzuführen ist. 相似文献
58.
M. C. Risueño G. Giménez-Martín J. F. López-Sáez 《Cellular and molecular life sciences : CMLS》1965,21(11):627-628
Résumé Il existen un certain rapport entre la chromatine et des petites invaginations de la membrane nucléaire. Nous estimons que la charge positive de la membrane et la charge négative des chromosomes peut être la cause inductrice. 相似文献
59.
Riassunto Viene descritto un metodo che consente di isolare una buona quantità di linfociti, completamente privi di eritrociti e di piastrine. Il metodo é basato sull'azione emolitica del NH4Cl e sulla ritensione dei granulociti e delle piastrine ad opera del cotone. Questo metodo è risultato molto soddisfacente anche per isolare le cellule di tipo mielocitario dai granulociti dal sangue di pasienti con leucemia mieloide cronica. 相似文献