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71.
A new design for an energy‐harvesting electrochromic window (EH‐ECW) based on the fusion of two technologies, organic electrochromic windows and dye‐sensitized solar cells (DSSCs), is presented. Unlike other power‐generating smart windows, such as photoelectrochromic devices that are passive and only contain two states (i.e., a closed‐circuit colored state and an open‐circuit bleaching state), EH‐ECW allows active tuning of the transmittance by varying the applied potential and it functions as a photovoltaic cell based on a DSSC. The resulting device demonstrates a fast switching rate of 1 s in both the bleaching and coloring processes through the use of an electrochromic polymer as a counter electrode layer. To increase the transmittance of the device, a cobalt redox couple and a light‐colored, yet efficient, organic dye are used. The organic dye contains a polymeric structure that contributes to the high cyclic stability. The device exhibits a power conversion efficiency (PCE) of 4.5% (100 mW cm‐2) under AM 1.5 irradiation, a change in transmittance of 34% upon applied potential, and shows only 3% degradation in the PCE after 5000 cycles.  相似文献   
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Background

A number of studies have revealed a link between chronic periodontitis and cardiovascular disease in obese patients. However, there is little information about the influence of periodontitis-associated bacteria, Porphyromonas gingivalis (Pg), on pathogenesis of atherosclerosis in obesity.

Methods

In vivo experiment: C57BL/6J mice were fed with a high-fat diet (HFD) or normal chow diet (CD), as a control. Pg was infected from the pulp chamber. At 6 weeks post-infection, histological and immunohistochemical analysis of aortal tissues was performed. In vitro experiment: hTERT-immortalized human umbilical vein endothelial cells (HuhT1) were used to assess the effect of Pg/Pg-LPS on free fatty acid (FFA) induced endothelial cells apoptosis and regulation of cytokine gene expression.

Results

Weaker staining of CD31 and increased numbers of TUNEL positive cells in aortal tissue of HFD mice indicated endothelial injury. Pg infection exacerbated the endothelial injury. Immunohistochemically, Pg was detected deep in the smooth muscle of the aorta, and the number of Pg cells in the aortal wall was higher in HFD mice than in CD mice. Moreover, in vitro, FFA treatment induced apoptosis in HuhT1 cells and exposure to Pg-LPS increased this effect. In addition, Pg and Pg-LPS both attenuated cytokine production in HuhT1 cells stimulated by palmitate.

Conclusions

Dental infection of Pg may contribute to pathogenesis of atherosclerosis by accelerating FFA-induced endothelial injury.  相似文献   
74.
Twelve dinucleotide markers were successfully isolated and characterized from a microsatellite‐enriched genomic library obtained for the gudgeon Squalidus chankaensis biwae. These markers were also available for the congeners S. c. tsuchigae and S. japonicus from Japan, which had five to 46 alleles and an expected heterozygosity ranging from zero to 0.946. Linkage equilibrium was observed at all loci, and most loci did not show significant deviation from Hardy–Weinberg equilibrium. The isolated microsatellite markers will be useful for genetic diversity studies of Squalidus populations.  相似文献   
75.
Inoue S  Yokota M  Nakada K  Miyoshi H  Hayashi J 《FEBS letters》2007,581(9):1910-1916
Anemia is a symptom in patients with Pearson syndrome caused by the accumulation of mutated mitochondrial DNA (mtDNA). Such mutated mtDNAs have been detected in patients with anemia. This suggested that respiration defects due to mutated mtDNA are responsible for the anemia. However, there has been no convincing experimental evidence to confirm the pathophysiological relation between respiration defects in hematopoietic cells and expression of anemia. We address this issue by transplanting bone marrow cells carrying pathogenic mtDNA with a large-scale deletion (ΔmtDNA) into normal mice. The bone marrow-transplanted mice carried high proportion of ΔmtDNA only in hematopoietic cells, and resultant the mice suffered from macrocytic anemia. They show abnormalities of erythroid differentiation and weak erythropoietic response to a stressful condition. These observations suggest that hematopoietic cell-specific respiration defects caused by mtDNAs with pathogenic mutations are responsible for anemia by inducing abnormalities in erythropoiesis.  相似文献   
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For the first step toward resolution of the higher-level relationships of the order Aulopiformes (Teleostei: Eurypterygii) using longer DNA sequences, we determined the complete mitochondrial DNA sequence for Aulopus japonicus (Aulopodidae). The entire genome was purified by gene amplification using a long PCR technique, and the products were subsequently used as templates for PCR with 63 fish-versatile and 3 species-specific primers that amplify contiguous, overlapping segments of the entire genome. Direct sequencing of the PCR products demonstrated that the genome (16 653 base pairs [bp]) contained the same 37 mitochondrial genes (2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes) as found in other vertebrates, with the gene order identical to that in typical vertebrates. Maximum-parsimony analysis using nucleotide sequences from the concatenated 12 protein-coding genes (no third codon positions and excluding the ND6 gene) plus 22 tRNA genes (stem regions only) from eight teleosts placed A. japonicus in a reasonable phylogenetic position; those from individual protein-coding genes and the concatenated 22 tRNA genes alone, however, did not reproduce the expected phylogeny with few exceptions, probably owing to insufficient phylogenetic information in these smaller data sets. This result suggests that further taxonomic sampling and sequencing efforts may clarify limits and intra- and interrelationships of this morphologically and ecologically diverse group of fishes using mitochondrial genomic (mitogenomic) data. Received: August 31, 2000 / Revised: December 20, 2000 / Accepted: January 23, 2001  相似文献   
78.
Sound symbolism, or the nonarbitrary link between linguistic sound and meaning, has often been discussed in connection with language evolution, where the oral imitation of external events links phonetic forms with their referents (e.g., Ramachandran & Hubbard, 2001). In this research, we explore whether sound symbolism may also facilitate synchronic language learning in human infants. Sound symbolism may be a useful cue particularly at the earliest developmental stages of word learning, because it potentially provides a way of bootstrapping word meaning from perceptual information. Using an associative word learning paradigm, we demonstrated that 14-month-old infants could detect Köhler-type (1947) shape-sound symbolism, and could use this sensitivity in their effort to establish a word-referent association.  相似文献   
79.
TRAF2 is a key molecule involved in TNF signaling, which is crucial for the regulation of inflammatory processes. We have identified a novel TRAF2 binding protein, designated as T2BP (TRAF2 binding protein), by a mammalian two-hybrid screening approach. T2BP is a relatively small protein of 184 amino acids, which includes a forkhead-associated domain, the phosphopeptide binding motif. The interaction domain search showed that the TRAF domain in TRAF2 is required for the binding to T2BP whereas almost the entire protein in T2BP binds to TRAF2. The interaction was further confirmed by co-immunoprecipitation. Expression profiling for T2BP and TRAF2 revealed an ubiquitous expression in adult mouse tissues. Overexpression of T2BP in HEK293 cells activated NF-kappaB and AP-1 in a dose dependent manner as well as seen in the TNF-treated control cells. Our results suggest that T2BP is involved in the TNF-mediated signaling by its interaction with TRAF2.  相似文献   
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