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61.
Mustonen H Lepistö A Lehtonen S Lehtonen E Puolakkainen P Kivilaakso E 《Biochemical and biophysical research communications》2005,332(2):426-432
The potential association of CD2AP with the adherens junction protein E-cadherin, co-localization with the actin cytoskeleton, and involvement in cell migration was investigated in cultured rat gastric mucosal cells. In stationary cells, CD2AP was localized perinuclearly while E-cadherin was expressed along cell-cell contacts and F-actin formed a branched network and adhesion belts. In migrating cells, CD2AP appeared as thread-like accumulations in the leading edges, colocalizing with F-actin and occasionally with E-cadherin. Intracellular injection of anti-CD2AP significantly retarded the migration speed of the cells suggesting a crucial role for CD2AP in mucosal cell migration, possibly as a scaffolding protein between cell membrane proteins and actin cytoskeleton. Co-immunoprecipitation assays revealed that CD2AP and E-cadherin are in a complex in HGF stimulated cells. It is concluded that CD2AP interacts with E-cadherin and co-localizes with F-actin in the leading edge of migrating cells, and significantly contributes to cell migration in restituting gastric epithelium. 相似文献
62.
Wojciech Walkusz Joclyn E. Paulić Sławomir Kwaśniewski William J. Williams Sally Wong Michael H. Papst 《Polar Biology》2010,33(3):321-335
Composition, abundance, biomass and distribution of zooplankton in the coastal Canadian Beaufort Sea were studied in the summer
of 2005 and 2006. Data were collected from two cross-shelf transects (11 stations in each). Sampling was conducted with vertical
hauls using a conical net of 153-μm mesh size. Our results revealed that there are three ecological zones, Intense Plume,
Diffuse Plume and oceanic, which are primarily shaped by the highly variable Mackenzie River plume. The Intense Plume Grouping
was located at stations influenced greatly by the Mackenzie River, where Podon leuckarti, Pseudocalanus spp., Copepoda nauplii and Limnocalanus macrurus were most abundant. The Diffuse Plume Grouping, that was located in the transitional zone between the river plume and the
ocean, had the highest diversity. This grouping was characterised by high abundance of Copepoda nauplii, Polychaeta larvae,
Pseudocalanus and L. macrurus. The Oceanic Grouping, located farthest from shore beyond the 85-m depth contour, was mainly inhabited by marine taxa—Calanus
glacialis, C. hyperboreus, Triconia (Oncea) borealis and Microcalanus spp.—and had the greatest overall zooplankton abundance and biomass of all groupings. 相似文献
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65.
Leendertz FH Lankester F Guislain P Néel C Drori O Dupain J Speede S Reed P Wolfe N Loul S Mpoudi-Ngole E Peeters M Boesch C Pauli G Ellerbrok H Leroy EM 《American journal of primatology》2006,68(9):928-933
During the period of December 2004 to January 2005, Bacillus anthracis killed three wild chimpanzees (Pan troglodytes troglodytes) and one gorilla (Gorilla gorilla gorilla) in a tropical forest in Cameroon. While this is the second anthrax outbreak in wild chimpanzees, this is the first case of anthrax in gorillas ever reported. The number of great apes in Central Africa is dramatically declining and the populations are seriously threatened by diseases, mainly Ebola. Nevertheless, a considerable number of deaths cannot be attributed to Ebola virus and remained unexplained. Our results show that diseases other than Ebola may also threaten wild great apes, and indicate that the role of anthrax in great ape mortality may have been underestimated. These results suggest that risk identification, assessment, and management for the survival of the last great apes should be performed with an open mind, since various pathogens with distinct characteristics in epidemiology and pathogenicity may impact the populations. An animal mortality monitoring network covering the entire African tropical forest, with the dual aims of preventing both great ape extinction and human disease outbreaks, will create necessary baseline data for such risk assessments and management plans. 相似文献
66.
Synchrotron small-angle X-ray scattering analysis of the bilayer structure of a pharmacologically relevant sterically stabilized liposome system is presented. Describing the electron density profile of the bilayer with the superposition of Gaussian functions, the contribution of the poly(ethylene glycol) (PEG) layers to the total electron density was identified. The changes in the thickness of the PEG layer as well as the distribution of the PEG chains among the outer and inner leaflets of the bilayers were followed by changing the molar ratio of the PEG-lipid and the molar weight of the PEG molecule. 相似文献
67.
Maria Ciofani Aviv Madar Carolina GalanMacLean Sellars Kieran MaceFlorencia Pauli Ashish AgarwalWendy Huang Christopher N. ParkurstMichael Muratet Kim M. NewberrySarah Meadows Alex GreenfieldYi Yang Preti JainFrancis K. Kirigin Carmen BirchmeierErwin F. Wagner Kenneth M. Murphy Richard M. MyersRichard Bonneau Dan R. Littman 《Cell》2012,151(2):289-303
68.
Soboliphyme baturini, a stomach-dwelling nematode of American martens (Martes Americana), reaches high levels of infection; however, its effects on the nutritional condition of the host are unknown. To understand the effects of this parasite on American martens, we collected S. baturini and measured abdominal fat deposits from 155 marten carcasses on Prince of Wales Island, southeastern Alaska, in the winter 2006-2007. We analyzed how the dried mass of abdominal fat varied as a function of S. baturini intensity. Parasite intensity and nutritional condition were not correlated; these results suggest that American martens were able to withstand even very high levels of S. baturini infection (up to 178 parasites per host). 相似文献
69.
Björkblom B Vainio JC Hongisto V Herdegen T Courtney MJ Coffey ET 《The Journal of biological chemistry》2008,283(28):19704-19713
JNKs are implicated in a range of brain pathologies and receive considerable attention as potential therapeutic targets. However, JNKs also regulate physiological and homeostatic processes. An attractive hypothesis from the drug development perspective is that distinct JNK isoforms mediate "physiological" and "pathological" responses. However, this lacks experimental evaluation. Here we investigate the isoforms, subcellular pools, and c-Jun/ATF2 targets of JNK in death of central nervous system neurons following withdrawal of trophic support. We use gene knockouts, gene silencing, subcellularly targeted dominant negative constructs, and pharmacological inhibitors. Combined small interfering RNA knockdown of all JNKs 1, 2, and 3, provides substantial neuroprotection. In contrast, knockdown or knock-out of individual JNKs or two JNKs together does not protect. This explains why the evidence for JNK in neuronal death has to date been largely pharmacological. Complete knockdown of c-Jun and ATF2 using small interfering RNA also fails to protect, casting doubt on c-Jun as a critical effector of JNK in neuronal death. Nonetheless, the death requires nuclear but not cytosolic JNK activity as nuclear dominant negative inhibitors of JNK protect, whereas cytosolic inhibitors only block physiological JNK function. Thus any one of the three JNKs is capable of mediating apoptosis and inhibition of nuclear JNK is protective. 相似文献
70.