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961.
The Ns genome of the genus Psathyrostachys possesses superior traits useful for wheat improvement. However, very little is known about the high molecular weight (HMW) subunits of glutenin encoded by the Ns genome. In this paper, we report the isolation of four alleles of HMW glutenin subunit gene from Psathyrostachys juncea. Sequence alignment data shows the four alleles have similar primary structure with those in wheat and other wheat-related grasses, with some unique modifications. All four sequences more closely resemble y-type, rather than x-type, glutenins. However, our results show three of the subunits (1Ns2-4) contain an extra glutamine residue in the N-terminal region not found on typical y-type subunits, as well as the x-type subunit specific sequence LAAQLPAMCRL. These three subunits likely represent an intermediate state in the divergence between x- and y-type subunits. Results also indicate that the Ns genome is more closely related to the St genome of Pseudoroegneria than any other Triticeae genomes.  相似文献   
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Daphnia (water fleas) are small crustaceans that undergo an unusual switch from asexual to sexual reproduction that is dependent on environmental conditions. In this study, a senescence-associated protein (SAP) from the common freshwater species Daphnia pulex was cloned using primers based on homologous sequences and rapid amplification of cDNA ends (RACE). Real-time PCR was employed to quantify the expression of D. pulex SAP (DpSAP) in individual organisms. The role of DpSAP in the reproductive transformation was further investigated in both parthenogenetic and sexual females by using digoxin-labeled SAP RNA probes and RNA whole-mount in situ hybridization. DpSAP was more highly expressed in sexual females, indicating a role in growth and reproduction. Cellular localization studies using RNA whole-mount in situ hybridization showed specific expression in the second tentacle joints. These expression patterns suggest an important role for DpSAP in the reproductive transformation of D. pulex.  相似文献   
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966.
A detailed investigation of the impact of molecular weight distribution of a photoactive polymer, poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT), on photovoltaic device performance and carrier transport properties is reported. It is found that different batches of as‐received polymers have substantial differences in their molecular weight distribution. As revealed by gel permeation chromatography (GPC), two peaks can generally be observed. One of the peaks corresponds to a high molecular weight component and the other peak corresponds to a low molecular weight component. Photovoltaic devices fabricated with a higher proportion of low molecular weight component have power conversion efficiencies (PCEs) reduced from 5.7% to 2.5%. The corresponding charge carrier mobility at the short‐circuit region is also significantly reduced from 2.7 × 10?5 to 1.6 × 10?8 cm2 V?1 s?1. The carrier transport properties of the polymers at various temperatures are further analyzed by the Gaussian disorder model (GDM). All polymers have similar energetic disorders. However, they appear to have significant differences in carrier hopping distances. This result provides insight into the origin of the molecular weight effect on carrier transport in polymeric semiconducting materials.  相似文献   
967.
Restenosis is one of clinical limitations for vein graft in coron- ary bypass graft. It has been proved that signal pathway IGF-1 and its receptor (IGF-1R) activated by hemodynamic mechanical stretch are responsible for the vascular smooth muscle cells proliferation in vein graft neointima formation. Unfortunately, there is no routinely successful method to resolve this problem. Gene delivering to vein graft possesses great therapeutic potential to prevent neointima formation. Polymer is one kind of nanoparticles, which can activate the process of endocytosis of cells. In this study, we evaluated the transfeetion efficiency and therapeutic potential of polymer- based transfection of plasmids expressing GFP and shRNAs targeting IGF-1R (pGFPshlGF-1Rs) to smooth muscle cells and rabbit external jugular vein graft. Results showed that polymer-based transfection provided high efficiency of trans- gene expression in smooth muscle cells in vitro. In vitro, IGF- 1R-specific shRNA transfected by polymer inhibited IGF-1R protein expression by 52 ±3.6%, when compared with mock transfected cells. In vivo delivering efficiency of pGFPshlGF-IR plasmid into the rabbit external jugular vein graft was significantly high in the polymer-based trans- fection group, when compared with negative control group. In vivo, polymer-based transfection IGF-1R-specific shRNA efficiently inhibited the expression of IGF-1R protein by 77 ± 3.6%, 65.6 ± 4.9%, and 76.7 ± 4.3% at 24, 48, and 72 h, respectively, when compared with negative control group. Our findings indicated that polymer-based transfec- tion may be a promising technique that allows the targeting of gene therapy for vein graft restenosis.  相似文献   
968.
Long noncoding RNAs (lncRNAs) play important roles in human diseases including vascular disease. Given the large number of lncRNAs, however, whether the majority of them are associated with vascular disease remains unknown. For this purpose, here we present a genomic location based bioinformatics method to predict the lncRNAs associated with vascular disease. We applied the presented method to globally screen the human lncRNAs potentially involved in vascular disease. As a result, we predicted 3043 putative vascular disease associated lncRNAs. To test the accuracy of the method, we selected 10 lncRNAs predicted to be implicated in proliferation and migration of vascular smooth muscle cells (VSMCs) for further experimental validation. The results confirmed that eight of the 10 lncRNAs (80%) are validated. This result suggests that the presented method has a reliable prediction performance. Finally, the presented bioinformatics method and the predicted vascular disease associated lncRNAs together may provide helps for not only better understanding of the roles of lncRNAs in vascular disease but also the identification of novel molecules for the diagnosis and therapy of vascular disease.  相似文献   
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Micro/macrowire intracranial EEG (iEEG) signals recorded from implanted micro/macroelectrodes in epileptic patients have received great attention and are considered to include much information of neuron activities in seizure transition compared to scalp EEG from cortical electrodes. Microelectrode is contacted more close to neurons than macroelectrode and it is more sensitive to neuron activity changes than macroelectrode. Microwire iEEG recordings are inevitably advantageous over macrowire iEEG recordings to reveal neuronal mechanisms contributing to the generation of seizures. In this study, we investigate the seizure generation from microwire iEEG recordings and discuss synchronization of microwire iEEGs in four frequency bands: alpha (1−30 Hz), gamma (30−80 Hz), ripple (80–250 Hz), and fast ripple (>250 Hz) via two measures: correlation and phase synchrony. We find that an increase trend of correlation or phase synchrony exists before the macroseizure onset mostly in gamma and ripple bands where the duration of the preictal states varied in different seizures ranging up to a few seconds (minutes). This finding is contrast to the well-known result that a decrease of synchronization in macro domains exists before the macroseizure onset. The finding demonstrates that it is only when the seizure has recruited enough surrounding brain tissue does the signal become strong enough to be observed on the clinical macroelectrode and as a result support the hypothesis of progressive coalescence of microseizure domains. The potential ramifications of such an early detection of microscale seizure activity may open a new window on treatment by making possible disruption of seizure activity before it becomes fully established.  相似文献   
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