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71.
The largest suborder of bark lice (Insecta: Psocodea: ‘Psocoptera’) is Psocomorpha, which includes over 3600 described species. We estimated the phylogeny of this major group with family‐level taxon sampling using multiple gene markers, including both nuclear and mitochondrial ribosomal RNA and protein‐coding genes. Monophyly of the suborder was strongly supported, and monophyly of three of four previously recognized infraorders (Caeciliusetae, Epipsocetae, and Psocetae) was also strongly supported. In contrast, monophyly of the infraorder Homilopsocidea was not supported. Based on the phylogeny, we divided Homilopsocidea into three independent infraorders: Archipsocetae, Philotarsetae, and Homilopsocidea. Except for a few cases, previously recognized families were recovered as monophyletic. To establish a classification more congruent with the phylogeny, we synonymized the families Bryopsocidae (with Zelandopsocinae of Pseudocaeciliidae), Calopsocidae (with Pseudocaeciliidae), and Neurostigmatidae (with Epipsocidae). Monophyly of Elipsocidae, Lachesillidae, and Mesopsocidae was not supported, but the monophyly of these families could not be rejected statistically, so they are tentatively maintained as valid families. The molecular tree was compared with a morphological phylogeny estimated previously. Sources of congruence and incongruence exist and the utility of the morphological data for phylogenetic estimation is evaluated. © 2014 The Linnean Society of London  相似文献   
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Metabolic syndrome (MetS) and chronic kidney disease (CKD) are individual risk factors for cardiovascular disease (CVD). Abnormal hemorheology may be associated with CVD in both disorders. The present study investigated the impact of MetS and CKD on hemorheology. We studied 138 adults (women/men=63/75, mean age=52.2 years), who included 87 participants with MetS and 33 with CKD. The hemorheology was assessed by the index of 'whole blood passage time (WBPT)' using the Micro Channel array Flow ANalyzer (MC-FAN). The WBPT values of MetS participants were significantly higher than those of non-MetS participants (52.5±13.1 vs. 46.3±7.7 sec, p=0.03). The WBPT values of CKD participants were significantly higher than those of non- CKD (55.5±12.7 vs. 48.6±11.0 sec, p=0.003). The significant influence of MetS and CKD on WBPT was qualified by their effect modification to WBPT (p=0.04). There was a significantly greater influence of the combination of MetS and CKD on WBPT (59.9±13.4 sec) in comparison to the influence of non-MetS and CKD (46.6±3.5) or non-CKD and MetS (50.0±12.2). The influence of the combination of MetS and CKD was clearer in men, relative to women. Abnormal hemorheology as assessed using MC-FAN may be enhanced by the combination of MetS and CKD.  相似文献   
74.
Many straits in the Japanese archipelago have been proposed as biogeographical boundaries, but there is disagreement regarding their importance as historic barriers against dispersal of terrestrial and freshwater taxa. Mitochondrial DNA haplotype and phylogenetic analyses of Lefua nikkonis, a primary freshwater fish inhabiting northern Japan and descendent from Siberia, revealed that the species is genetically structured within its geographic range, but that two major haplotypes are widely distributed across the Ishikari Lowland of Hokkaido Island as well as across the Tsugaru Strait between Hokkaido and Honshu Islands, two well-known biogeographical boundaries of northern Japan. The two major haplotypes were separated from each other by only one mutational step, and many other haplotypes, including those endemic to the region south of these barriers, have diverged from the major haplotypes, suggesting rapid range expansion and local differentiation. Divergence-time estimates, based on vicariance of the Honshu endemic congener L. echigonia via uplift of the Central Highlands, demonstrated that the southward dispersal of L. nikkonis from Hokkaido Island to Honshu Island occurred less than 0.08–0.19 Mya, suggesting that a land bridge emerged at the Tsugaru Strait during the Riss glaciation. Given that other freshwater taxa crossed the strait earlier (during the Middle Pleistocene), it is likely that land bridges in the strait have repeatedly emerged. The fact that L. nikkonis invaded only the northern part of Honshu, and that many other freshwater species also have the limit of their distribution ranges in this area as well, indicates that a faunal transition zone might persist even without the Tsugaru Strait. Thus, straits and lowlands in northern Japan are likely to have been less important as dispersal barriers to freshwater taxa than is currently thought.  相似文献   
75.
Serum starvation induces binucleation in HeLa cells, but the effects of serum starvation on mitosis and the significance of binucleation remain unknown. We investigated the effect of serum starvation on mitosis and analyzed the growth of binucleated cells. The frequency of binucleation caused by cytokinesis failure in DMEM without FBS (0% medium) was higher than that in DMEM with FBS (10% medium). In 0% medium, the metaphase spindle location was off-center, and RhoA localization significantly lacked symmetry. The frequency of the extension of intercellular bridge with the midbody in 0% medium was significantly higher than that in 10% medium. Moreover, all mononucleated mitotic cells caused bipolar mitosis and produced only mononucleated daughter cells, but binucleated cells produced various nucleated cells by multipolar mitosis in 0% medium. These results suggest that serum starvation may have various effects on mitosis, and binucleated cells may be related to formation of aneuploidy.  相似文献   
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77.
Paralytic peptide of Bombyx mori (BmPP) is one of the multifunctional ENF-peptides; the name of “ENF” is the consensus N-terminal amino acid sequence of the family peptides. We revealed that BmPP significantly possesses growth-blocking activity and plasmatocyte-spreading activity and that its activity profiles are different from those of another ENF-family peptide, namely, the growth-blocking peptide of Pseudaletia separata (PsGBP). We also determined the NMR structures of BmPP and PsGBP under the same conditions, which revealed the structural differences of the first and second β-turn regions between the two peptides. On the basis of our results, it can be considered that the tertiary structural difference in these peptides may cause their different profiles of growth-blocking activity.  相似文献   
78.
A novel phage library has been prepared using the Escherichia coli genome digested with three restriction enzymes. The resulting DNA fragments were ligated to the expression vector pCANTAB5 to obtain the library of recombinant M13 phages displaying relatively long exogenous peptides. The library was screened to isolate recombinant phages with high affinity to alkaline phosphatase (AP) from calf intestine. After four rounds of panning three phages (AP1, AP2 and AP3) were shown to have specific binding properties toward AP by enzyme-linked immunosorbent assay. The phages were further characterized by surface plasmon resonance (SPR). Among the three phages AP3 bound the AP-immobilized sensor chip most and caused the highest resonant angle shift. The sensor response decreased with the decrease of the concentration of AP3 added. Furthermore, displacement of AP3 from the AP-immobilized sensor chip was observed upon injection of AP solution to the SPR system, whereas injection of bovine serum albumin solution led to the great increase of the sensor response. This result indicates the specific binding of AP3 to AP.  相似文献   
79.
In diffusely growing plant cells, cortical microtubules play an important role in regulating the direction of cell expansion. Arabidopsis (Arabidopsis thaliana) spiral2 (spr2) mutant is defective in directional cell elongation and exhibits right-handed helical growth in longitudinally expanding organs such as root, hypocotyl, stem, petiole, and petal. The growth of spr2 roots is more sensitive to microtubule-interacting drugs than is wild-type root growth. The SPR2 gene encodes a plant-specific 94-kD protein containing HEAT-repeat motifs that are implicated in protein-protein interaction. When expressed constitutively, SPR2-green fluorescent protein fusion protein complemented the spr2 mutant phenotype and was localized to cortical microtubules as well as other mitotic microtubule arrays in transgenic plants. Recombinant SPR2 protein directly bound to taxol-stabilized microtubules in vitro. Furthermore, SPR2-specific antibody and mass spectrometry identified a tobacco (Nicotiana tabacum) SPR2 homolog in highly purified microtubule-associated protein fractions from tobacco BY-2 cell cultures. These results suggest that SPR2 is a novel microtubule-associated protein and is required for proper microtubule function involved in anisotropic growth.  相似文献   
80.
Torymus koreanus (Hymenoptera: Torymidae) was reared from galls of Dryocosmus kuriphilus (Hymenoptera: Cynipidae) for the first time in Japan. We here report morphological features and partial mtDNA sequencing data of T. koreanus. Torymus koreanus has several common characteristics with species of the cyaneus group defined by Zavada (2003 ). According to the key to species groups defined by Graham and Gijswijt (1998 ), it does not belong to any species group because of the entire posterior margin of metasomal tergum five.  相似文献   
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