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21.
The development of spontaneous object manipulation in 5 chimpanzees (Pan troglodytes) from ages 15 to 54 months was investigated, focusing on formal properties of subjects’ acts and the objects they manipulated.
Young chimpanzees’ manipulation progress from serial one-at-a-time acts on one object to parallel two-at-a-time acts on two
or more objects. With age, simultaneous acts become increasingly transformational and identical or reciprocal to each other.
Moreover, the class properties of objects manipulated simultaneously change. When presented with objects belonging to two
different classes, subjects shift, with age, from manipulating different objects to manipulating identical or similar objects.
In all these respects young chimpanzee’ development is similar to human infants’. In others it differs. Most especially, the
onset age is later and the development is slower as well as less structurally complex. 相似文献
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CD and NMR conformational studies of a peptide encompassing the Mid Loop interface of Ship2–Sam
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Concetta Di Natale Daniela Marasco Maurizio Pellecchia Marilisa Leone 《Biopolymers》2014,101(11):1088-1098
The lipid phosphatase Ship2 is a protein that intervenes in several diseases such as diabetes, cancer, neurodegeneration, and atherosclerosis. It is made up of a catalytic domain and several protein docking modules such as a C‐terminal Sam (Sterile alpha motif) domain. The Sam domain of Ship2 (Ship2–Sam) binds to the Sam domains of the EphA2 receptor (EphA2–Sam) and the PI3K effector protein Arap3 (Arap3–Sam). These heterotypic Sam–Sam interactions occur through formation of dimers presenting the canonical “Mid Loop/End Helix” binding mode. The central region of Ship2–Sam, spanning the C‐terminal end of α2, the α3 and α4 helices together with the α2α3 and α3α4 interhelical loops, forms the Mid Loop surface that is needed to bind partners Sam domains. A peptide encompassing most of the Ship2–Sam Mid Loop interface (Shiptide) capable of binding to both EphA2–Sam and Arap3–Sam, was previously identified. Here we investigated the conformational features of this peptide, through solution CD and NMR studies in different conditions. These studies reveal that the peptide is highly flexible in aqueous buffer, while it adopts a helical conformation in presence of 2,2,2‐trifluoroethanol. The discovered structural insights and in particular the identification of a helical motif, may lead to the design of more constrained and possibly cell permeable Shiptide analogs that could work as efficient antagonists of Ship2–Sam heterotypic interactions and embrace therapeutic applications. © 2014 Wiley Periodicals, Inc. Biopolymers 101: 1088–1098, 2014. 相似文献
25.
Figura N Franceschi F Santucci A Bernardini G Gasbarrini G Gasbarrini A 《Helicobacter》2010,15(Z1):60-68
The possible role of Helicobacter pylori as a trigger for some extragastric diseases has been largely investigated in the last year. There are, in fact, several studies concerning cardiovascular diseases, neurological disorders, diabetes mellitus, ear and eyes diseases, immunological and hematological disorders, liver and bile tract diseases, gynecological and respiratory tract pathologies. Among them, idiopathic sideropenic anemia and idiopathic thrombocytopenic purpura still remain the extragastric diseases showing the most convincing results. Concerning ischemic heart disease, there are new interesting data playing in favor of the association, even though there are still some open issues to be clarified. For the other diseases, more studies are needed to clarify the reality of the proposed association. 相似文献
26.
Vance L Trudeau Gustavo M Somoza Guillermo S Natale Bruce Pauli Jacqui Wignall Paula Jackman Ken Doe Fredrick W Schueler 《Reproductive biology and endocrinology : RB&E》2010,8(1):36
Background
It is well known that many anurans do not reproduce easily in captivity. Some methods are based on administration of mammalian hormones such as human chorionic gonadotropin, which are not effective in many frogs. There is a need for simple, cost-effective alternative techniques to induce spawning. 相似文献27.
Clonogenic assay is a widely used experimental approach to test for the effects of drugs/genes on the growth and proliferative
characteristics of cells in vitro. Accurate quantitation of treatment effects in clonogeneic assays depends on the ability
to visualize and count cell colonies precisely. We report a novel method (referred as ETeB) for staining cell colonies grown
on plastic and specially coated substrates like collagen. Using colon cancer cell lines grown on plastic and collagen, we
compared the colony staining efficiencies of the widely used methylene blue, and Ethidium bromide (ETeB) stains. Results show
that the ETeB protocol works well on plastic and is extremely effective for staining colonies on collagen when compared to
methylene blue. The key features and advantages of ETeB technique are; (a) reduction in background for colonies grown on collagen
and possibly other substrates, (b) the whole procedure takes less than a minute, (c) no post-stain washing step is required
which eliminates colony losses for cell lines that are loosely adherent, (d) colony visualization and counting can be done
immediately following the staining procedure using a standard UV illuminator and software, and (e) the method works across
a wide variety of cell lines. The simplicity and robustness of this procedure should warrant its usage in both small and large-scale
clonogenic experiments.
相似文献
Kishore GudaEmail: |
28.
Differential detection of potentially hazardous Fusarium species in wheat grains by an electronic nose 总被引:1,自引:0,他引:1
Fungal infestation on wheat is an increasingly grave nutritional problem in many countries worldwide. Fusarium species are especially harmful pathogens due to their toxic metabolites. In this work we studied volatile compounds released by F. cerealis, F. graminearum, F. culmorum and F. redolens using SPME-GC/MS. By using an electronic nose we were able to differentiate between infected and non-infected wheat grains in the post-harvest chain. Our electronic nose was capable of distinguishing between four wheat Fusaria species with an accuracy higher than 80%. 相似文献
29.
D'Abrosca B Dellagreca M Fiorentino A Monaco P Natale A Oriano P Zarrelli A 《Phytochemistry》2005,66(22):2681-2688
Isolation, chemical characterization and phytotoxicity of nine polyhydroxylated terpenes (five C13nor-isoprenoids, two sesquiterpenes, a spirostane and a pseudosapogenin) from Cestrum parqui L'Herr are reported. In this work we completed the phytochemical investigation of the terpenic fraction of the plant and described the structural elucidation of polar isoprenoids using NMR methods. All the configurations of the compounds have been assigned by NOESY experiments. Four new structures have been identified as (3S,5R,6R,7E,9R)-5,6,9-trihydroxy-3-isopropyloxy-7-megastigmene, 5alpha-spirostan-3beta,12beta,15alpha-triol, and 26-O-(3'-isopentanoyl)-beta-d-glucopyranosyl-5alpha-furost-20(22)-ene-3beta,26-diol, and as an unusual tricyclic sesquiterpene. The compounds have been assayed for their phytotoxicity on lettuce at the concentrations ranging between 10(-4) and 10(-7)M. The activities of some compounds were similar to that of the herbicide pendimethalin. 相似文献
30.
p38 MAPK signaling during murine preimplantation development 总被引:7,自引:0,他引:7
Mitogen-activated protein kinase (MAPK) pathways mediate some important cellular processes and are likely to also regulate preimplantation development. The role of p38 MAP kinase signaling during murine preimplantation development was investigated in the present study. p38 MAPK, p38-regulated or -activated kinase (PRAK; MK5), map kinase-activated protein kinase 2 (MK2), and heat shock protein 25 (hsp25) mRNAs and proteins were detected throughout preimplantation development. Two-cell stage embryos cultured in the presence of SB220025 and SB203580 (specific inhibitors of p38 MAPK alpha/beta), progressed to the eight-cell stage with the same frequency as controls; however, treated embryos halted their development at the 8- to 16-cell stage. In addition, embryos treated with p38 MAPK inhibitors displayed a complete loss of MK2 and hsp25 phosphorylation and also a complete loss of filamentous actin as indicated by the absence of rhodamine-phalloidin staining. In these inhibitor-treated groups, the embryos were composed of a mixture of compacting and noncompacting cells, and the embryos were one to two cell divisions behind controls. Treated embryos remained viable as the developmental blockade was rescued by removing embryos from the drug treatment and placing them in drug-free medium until they progressed to the blastocyst stage. This study demonstrates that p38 MAPK activity is required to support development through the murine preimplantation interval. 相似文献