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81.
A morroniside cinnamic acid conjugate was prepared and evaluated on E-selectin mediated cell–cell adhesion as an important role in inflammatory processes. 7-O-Cinnamoylmorroniside exhibited excellent anti-inflammatory activity (IC50 = 49.3 μM) by inhibiting the expression of E-selectin; further, it was more active than another cinnamic-acid-conjugated iridoid glycoside (harpagoside; IC50 = 88.2 μM), 7-O-methylmorroniside, and morroniside itself. As a result, 7-O-cinnamoylmorroniside was observed to be a potent inhibitor of TNF-α-induced E-selectin expression.  相似文献   
82.
83.
Induced pluripotent stem (iPS) cells have the pluripotency to differentiate into broad spectrum derivatives of all three embryonic germ layers. However, the in vitro organ differentiation potential of iPS cells to organize a complex and functional “organ” has not yet been demonstrated. Here, we demonstrate that mouse iPS cells have the ability to organize a gut-like organ with motor function in vitro by a hanging drop culture system. This “induced gut (iGut)” exhibited spontaneous contraction and highly coordinated peristalsis accompanied by a transportation of contents. Ultrastructural analysis identified that the iGut had large lumens surrounded by three distinct layers (epithelium, connective tissue and musculature). Immunoreactivity for c-Kit, a marker of interstitial cells of Cajal (ICCs, enteric pacemaker cells), was observed in the wall of the lumen and formed a distinct and dense network. The neurofilament immunoreactivity was identified to form large ganglion-like structures and dense neuronal networks. The iGut was composed of all the enteric components of three germ layers: epithelial cells (endoderm), smooth muscle cells (mesoderm), ICCs (mesoderm), and enteric neurons (ectoderm). This is the first report to demonstrate the in vitro differentiation potential of iPS cells into particular types of functional “organs.” This work not only contributes to understanding the mechanisms of incurable gut disease through disease-specific iPS cells, but also facilitates the clinical application of patient-specific iPS cells for novel therapeutic strategies such as patient-specific “organ” regenerative medicine in the future.  相似文献   
84.
As the integral components of zooplankton in the subarctic NorthPacific, the three Neocalanus species (N. cristatus, N. plumchrusand N. flemingeri) are characterized by an annual life cycleand rapid development in the surface layer during spring–summer.Patterns of interannual variation of abundance and body sizeof these Neocalanus species were analyzed using the time-seriesdata collected during the summers of 1979–1998 (20 years)at stations along the longitudinal transect line in the centralNorth Pacific, crossing five sub-areas (Alaska Current System,Subarctic Current System, Northern Transition Domain, SouthernTransition Domain and Subtropical Current System). In the southernsub-areas, quasi-decadal oscillation was observed for the 3-yearrunning mean of abundance and prosome length for copepoditestage 5 (C5) of the three Neocalanus species. Although the oscillationsignal diminished towards northern waters, it showed a positivephase during the early 1980s and 1990s and a negative phaseduring the late 1980s. In the northern waters, a biennial patternwas pronounced for anomalies of C5 prosome length for N. plumchrusand N. flemingeri, which was large in odd years and small ineven years. Significantly positive covariations among the threespecies were found for both abundance and prosome length aroundmid-latitude, where they were abundant. In the correlation analysis,these observed yearly patterns showed a statistically insignificantcorrelation with most environmental (integrated mean temperaturein surface waters, water column stability and chlorophyll aconcentration) or climatological (North Pacific Index and SouthernOscillation Index) variables. The regional difference of theoscillation signal and the synchronized covariation among thesespecies suggest that interannual variations of their abundanceand body size are mediated by common environmental force(s)with some spatial and temporal scales in the subarctic NorthPacific.  相似文献   
85.
Electron lifetime (tau) in dye-sensitized solar cells (DSC), using electrolytes containing I-/I3- redox couple, was investigated with quaternary ammonium cations having various alkyl chain lengths, and it was found that the lifetime increased in the order tau(TPA) approximately tau(TBA) < tau(THA) approximately tau(THpA), where tau(TPA), tau(TBA), tau(THA) and tau(THpA) were the lifetimes with tetra-propyl, butyl, hexyl and heptyl ammonium cations respectively. On the other hand, little influence of the cations on electron diffusion coefficients was observed, indicating that the DSCs using these cations have longer electron diffusion length (L). New electrolyte compositions for DSCs were sought with THA+ to increase the lifetime and L without compromising charge injection yield from the dye to TiO2. The electrolyte was applied for DSCs using TiO2 electrode prepared by 150 degrees C sintering. Under one-sun conditions (100 mW cm(-2)), newly prepared electrolytes showed at most 40% increase of energy conversion efficiency in comparison to conventional electrolytes and the highest value was 4.7%, which was the highest among the reported values of low temperature processed DSCs. The increase of the efficiency was achieved by higher short-circuit current induced by longer electron diffusion length and higher open-circuit voltage due to higher electron density.  相似文献   
86.
Thioredoxin, an antioxidant protein, is a promising molecule for development of functional foods because it protects the gastric mucosa and reduces the allergenicity of allergens. To establish a method for obtaining an ample amount of yeast thioredoxin, we found here that thioredoxin is released from Saccharomyces cerevisiae by treatment with 20% ethanol. We also found that Japanese sake contains a considerable amount of thioredoxin.  相似文献   
87.
The production of 1,4-dihydroxy-2-naphthoic acid (DHNA) was investigated using a fed-batch culture of Propionibacterium freudenreichii ET-3. DHNA is a precursor of menaquinone (MK) and is transformed to MK by combination with an isoprenoid unit. We found that ET-3 stopped MK production and increased DHNA production in an anaerobic fed-batch culture by maintaining the lactose concentration at approximately zero. The maximum DHNA concentration observed in the anaerobic fed-batch culture was markedly higher than the maximum DHNA concentration observed in an anaerobic batch culture. Moreover, MK or DHNA production was affected by the lactose feeding rate; this suggests that lactose metabolism participates in the syntheses of these products. On the other hand, accumulation of propionate was found to inhibit DHNA production in the fed-batch culture. Based on the fact that ET-3 increases DHNA production in an aerobic culture by consuming propionate, we carried out a cultivation experiment in which an anaerobic fed-batch culture was switched to an anaerobic batch culture and found that the DHNA production was increased to a greater extent than the DHNA production in an anaerobic fed-batch culture. These results suggest that DHNA production by ET-3 is markedly influenced by carbon source limitation and the oxygen supply.  相似文献   
88.
The research presented herein provides valuable data with respect to the phosphorus content of starches from many potato (Solanum tuberosum L.) cultivars using an energy-dispersive X-ray fluorescence technique. In all starches examined, the phosphorus content ranged from 308 to 1244 ppm. Furthermore, the estimation of the starch characteristics of representative samples differing manifestly in their phosphorus content indicated that enhancing the starch phosphate resulted in significant increases in the swelling power, peak viscosity, and breakdown and significant but small increases in the onset and peak temperatures of gelatinization. Other starch quality parameters, such as the amylose content, median granule size, and the gelatinization enthalpy, did not change significantly due to the degree of phosphate substitution of starch.  相似文献   
89.
90.
The production of 1,4-dihydroxy-2-naphthoic acid (DHNA) was investigated using a fed-batch culture of Propionibacterium freudenreichii ET-3. DHNA is a precursor of menaquinone (MK) and is transformed to MK by combination with an isoprenoid unit. We found that ET-3 stopped MK production and increased DHNA production in an anaerobic fed-batch culture by maintaining the lactose concentration at approximately zero. The maximum DHNA concentration observed in the anaerobic fed-batch culture was markedly higher than the maximum DHNA concentration observed in an anaerobic batch culture. Moreover, MK or DHNA production was affected by the lactose feeding rate; this suggests that lactose metabolism participates in the syntheses of these products. On the other hand, accumulation of propionate was found to inhibit DHNA production in the fed-batch culture. Based on the fact that ET-3 increases DHNA production in an aerobic culture by consuming propionate, we carried out a cultivation experiment in which an anaerobic fed-batch culture was switched to an anaerobic batch culture and found that the DHNA production was increased to a greater extent than the DHNA production in an anaerobic fed-batch culture. These results suggest that DHNA production by ET-3 is markedly influenced by carbon source limitation and the oxygen supply.  相似文献   
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