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101.
102.
Joan Madurell-Malapeira David M. Alba Salvador Moyà-Solà Josep Aurell-Garrido 《Comptes Rendus Palevol》2010,9(1-2):55-62
Fossil puma-like cats (Puma pardoides) are recorded from several Late Pliocene to Early Pleistocene Eurasian localities, but the interpretation of the phylogenetic relationships between them and the extant puma (Puma concolor) remains controversial. In the past, extinct puma-like cats have been classified into several genera and species, and a close relationship with both pumas (Puma concolor) and snow leopards (Uncia uncia) has been suggested. Here, we describe the fossil remains of puma-like cats from the Iberian Peninsula. These remains (from the localities of La Puebla de Valverde, Cueva Victoria and Vallparadís) cover the whole known chronological distribution of this species in Eurasia. Although there are dentognathic similarities with U. uncia, the Iberian remains of P. pardoides most closely resemble the extant P. concolor. It is concluded that P. pardoides is closely related to living pumas, which supports a likely Eurasian origin of the puma lineage. 相似文献
103.
Background
Understanding evolutionary processes that drive genome reduction requires determining the tempo (rate) and the mode (size and types of deletions) of gene losses. In this study, we analysed five endosymbiotic genome sequences of the gamma-proteobacteria (three different Buchnera aphidicola strains, Wigglesworthia glossinidia, Blochmannia floridanus) to test if gene loss could be driven by the selective importance of genes. We used a parsimony method to reconstruct a minimal ancestral genome of insect endosymbionts and quantified gene loss along the branches of the phylogenetic tree. To evaluate the selective or functional importance of genes, we used a parameter that measures the level of adaptive codon bias in E. coli (i.e. codon adaptive index, or CAI), and also estimates of evolutionary rates (Ka) between pairs of orthologs either in free-living bacteria or in pairs of symbionts. 相似文献104.
We investigated the role of receptor binding affinity in surface adhesion. A sensitive technique was developed to measure the surface energy of receptor-mediated adhesion. The experimental system involved a functionalized elastic agarose bead resting on a functionalized glass coverslip. Attractive intersurface forces pulled the two surfaces together, deforming the bead to produce an enlarged contact area. The Johnson-Kendall-Roberts (JKR) model was used to relate the surface energy of the interaction to the elasticity of the bead and the area of contact. The surface energies for different combinations of modified surfaces in solution were obtained from reflection interference contrast microscopy (RICM) measurements of the contact area formed by the bead and the coverslip. Studies with surfaces functionalized with ligand-receptor pairs showed that the relationship between surface energy and the association constant of the ligand binding has two regimes. At low binding affinity, surface energy increased linearly with the association constant, while surface energy increased logarithmically with the association constant in the high affinity regime. 相似文献
105.
106.
Schwarzenbacher R Canaves JM Brinen LS Dai X Deacon AM Elsliger MA Eshaghi S Floyd R Godzik A Grittini C Grzechnik SK Guda C Jaroszewski L Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA McMullan D McPhillips TM Miller MA Miller MD Morse A Moy K Ouyang J Robb A Rodrigues K Selby TL Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Hodgson KO Wooley J Wilson IA 《Proteins》2003,53(1):142-145
107.
Heine A Canaves JM von Delft F Brinen LS Dai X Deacon AM Elsliger MA Eshaghi S Floyd R Godzik A Grittini C Grzechnik SK Guda C Jaroszewski L Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA McMullan D McPhillips TM Miller MA Miller MD Morse A Moy K Ouyang J Page R Robb A Rodrigues K Schwarzenbacher R Selby TL Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Hodgson KO Wooley J Wilson IA 《Proteins》2004,56(2):387-391
108.
Schwarzenbacher R Jaroszewski L von Delft F Abdubek P Ambing E Biorac T Brinen LS Canaves JM Cambell J Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Eshagi S Floyd R Godzik A Grittini C Grzechnik SK Hampton E Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Ouyang J Page R Quijano K Robb A Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2004,55(3):768-771
109.
Spraggon G Schwarzenbacher R Kreusch A Lee CC Abdubek P Ambing E Biorac T Brinen LS Canaves JM Cambell J Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Eshagi S Floyd R Godzik A Grittini C Grzechnik SK Hampton E Jaroszewski L Karlak C Klock HE Koesema E Kovarik JS Kuhn P Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Ouyang J Page R Quijano K Robb A Stevens RC van den Bedem H Velasquez J Vincent J von Delft F Wang X West B Wolf G Xu Q Hodgson KO Wooley J Lesley SA Wilson IA 《Proteins》2004,55(4):1078-1081
110.
Haxhinasto K Kamath A Blackwell K Bodmer J Van Heukelom J English A Bai EW Moy AB 《American journal of physiology. Cell physiology》2004,287(4):C1125-C1138
The cytoskeleton is critical to the viral life cycle. Agents like cytochalasin inhibit viral infections but cannot be used for antiviral therapy because of their toxicity. We report the efficacy, safety, and mechanisms by which gene delivery of human wild-type low-molecular-weight caldesmon (l-CaD) protects cell membrane integrity from adenovirus infection in a DF-1 cell line, an immortalized avian fibroblast that is null for l-CaD. Transfection with an adenovirus (Ad)-controlled construct mediated a dose-dependent decline in transcellular resistance. In accordance with a computational model of cytoskeletal membrane properties, Ad disturbed cell-cell and cell-matrix adhesion and membrane capacitance. Transfection with the Ad-l-CaD construct attenuated adenovirus-mediated loss in transcellular resistance. Quantitation of vinculin-stained plaques revealed an increase in total focal contact mass in monolayers transfected with the Ad-l-CaD construct. Expression of l-CaD protected transcellular resistance through primary effects on membrane capacitance and independently of actin solubility and effects on prestress, as measured by the decline in isometric tension in response to cytochalasin D. Expression of l-CaD exhibited less Trypan blue cell toxicity than cytochalasin, and, unlike cytochalasin, it did not interfere with wound closure or adversely effect transcellular resistance. These findings demonstrate the gene delivery of wild-type human l-CaD as a potentially efficacious and safe agent that inhibits some of the cytopathic effects of adenovirus. adhesion; motility; computational modeling; focal contact; quantitation 相似文献