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21.
We investigated the effects of oolong tea on the basic metabolism of plasma lipids in mice under restraint stress. When a lipid emulsion (Intralipid 20%; a lipid emulsion containing 20% soybean oil) was injected intravenously into mice, the restraint stress prolonged the half-life (T 1/2) of elimination for plasma triglyceride (TG) from 28.7 to 55.5 min. The elimination rate per minute was 48.2% in stressed mice with the rate in starved control mice as 100%. Therefore, TG metabolism was disrupted by the stress, and the use of TG as an energy source decreased. We found that the metabolism of lipids significantly response to the restrained stress in the present study. Plasma TG was 515.9 +/- 29.9mg/dl 35min after Intralipid administration in control stressed mice, 478.7 +/- 26.7 mg/dl in the stressed group given caffeine 100 mg/kg of body weight, and 418.3 +/- 18.4 mg/dl in the stressed group given 1,000 mg/kg oolong tea, an improvement by 7.2% and 18.9%, respectively, with the value for the untreated control group. The intake of oolong tea alleviated the stress-induced decrease in the rate of blood lipid metabolism; this effect may have arisen from some non-specific stress-relieving property of the tea or from acceleration of lipid metabolism by properties of polyphenols, etc. in tea. Oolong tea had anti-stress effects on plasma TG metabolism, and the effects did not depend on caffeine.  相似文献   
22.

Purpose

To assess the feasibility of texture analysis for classifying fibrosis stage and necroinflammatory activity grade in patients with chronic hepatitis C on T2-weighted (T2W), T1-weighted (T1W) and Gd-EOB-DTPA-enhanced hepatocyte-phase (EOB-HP) imaging.

Materials and methods

From April 2008 to June 2012, MR images from 123 patients with pathologically proven chronic hepatitis C were retrospectively analyzed. Texture parameters derived from histogram, gradient, run-length matrix, co-occurrence matrix, autoregressive model and wavelet transform methods were estimated with imaging software. Fisher, probability of classification error and average correlation, and mutual information coefficients were used to extract subsets of optimized texture features. Linear discriminant analysis in combination with 1-nearest neighbor classifier (LDA/1-NN) was used for lesion classification. In compliance with the software requirement, classification was performed based on datasets from all patients, the patient group with necroinflammatory activity grade 1, and that with fibrosis stage 4, respectively.

Results

Based on all patient dataset, LDA/1-NN produced misclassification rates of 28.46%, 35.77% and 20.33% for fibrosis staging and 34.15%, 25.20% and 28.46% for necroinflammatory activity grading in T2W, T1W and EOB-HP images. In the patient group with necroinflammatory activity grade 1, LDA/1-NN yielded misclassification rates of 5.00%, 0% and 12.50% for fibrosis staging in T2W, T1W and EOB-HP images respectively. In the patient group with fibrosis stage 4, LDA/1-NN yielded misclassification rates of 5.88%, 12.94% and 11.76% for necroinflammatory activity grading in T2W, T1W and EOB-HP images respectively.

Conclusion

Texture quantitative parameters of MR images facilitate classification of the fibrosis stage as well as necroinflammatory activity grade in chronic hepatitis C, especially after categorizing the input dataset according to the activity or fibrosis degree in order to remove the interference between the fibrosis stage and necroinflammatory activity grade on texture features.  相似文献   
23.
The L-rhamnose isomerase gene (rhi) of Mesorhizobium loti was cloned and expressed in Escherichia coli, and then characterized. The enzyme exhibited activity with respect to various aldoses, including D-allose and L-talose. Application of it in L-talose production from galactitol was achieved by a two-step reaction, indicating that it can be utilized in the large-scale production of L-talose.  相似文献   
24.
The accuracy of estimating deer density using the fecal pellet count method is greatly limited by variability of the fecal decomposition rate. The fecal accumulation rate technique can avoid the issue of decomposition rate. However, the precision of this technique is not clear when the decomposition rate is relatively high, such as in Japanese forests. We estimated deer population densities on Yakushima Island by the fecal accumulation rate technique and compared them between seasons. The estimated densities were similar to reported estimates, and did not differ seasonally, in accord with reports that deer on Yakushima do not migrate seasonally. Thus, we conclude that the fecal accumulation rate technique is applicable in Japanese forests.  相似文献   
25.
The single-nucleotide polymorphisms (SNPs) in the human DNase I gene (DNASE1) might be involved in susceptibility to some common diseases; however, only limited population data are available. Further, the effects of these SNPs on in vivo DNase I activity remain unknown. The genotype and haplotype of all the SNPs in DNASE1 were determined in 3 ethnic groups including 14 populations using newly developed methods. Together with our previous data on the nonsynonymous SNPs, two major haplotypes based on the five exonic SNPs were identified; genetic diversity in the Asian population was low. Among 10 SNPs, other than exonic SNPs in the gene, only 3 were polymorphic among all the populations. Haplotype distribution, based on all the polymorphic SNPs, was clarified to be generally varied in an ethnic-dependent manner. Thus, the genetic aspects of DNASE1 with regard to all the SNPs in wide-ranging ethnic groups could be first demonstrated. Further, there was no correlation of all the polymorphic SNPs other than nonsynonymous ones with serum DNase I activity levels. Polymorphic SNPs other than the exonic SNPs might not be directly related to common diseases through alterations in in vivo levels of the activity.  相似文献   
26.
27.
Heterospecific communication signals sometimes convey relevant information for animal survival. For example, animals use or eavesdrop on heterospecific alarm calls concerning common predators. Indeed, most observations have been reported regarding anti-predator strategies. Use of heterospecific signals has rarely been observed as part of a foraging strategy. Here, I report empirical evidence, collected using playback experiments, showing that Japanese sika deer, Cevus nippon, use heterospecific food calls of Japanese macaques, Macaca fuscata yakui, for foraging efficiency. The deer and macaques both inhabit the wild forest of Yakushima Island with high population densities and share many food items. Anecdotal observations suggest that deer often wait to browse fruit falls under the tree where a macaque group is foraging. Furthermore, macaques frequently produce food calls during their foraging. If deer effectively obtain fruit from the leftovers of macaques, browsing fruit fall would provide a potential benefit to the deer, and, further, deer are likely to associate macaque food calls with feeding activity. The results showed that playback of macaque food calls under trees gathered significantly more deer than silence control periods. These results suggest that deer can associate macaque food calls with foraging activities and use heterospecific calls for foraging efficiency.  相似文献   
28.
Liver steatosis was once believed to be a benign condition, with rare progression to chronic liver disease. Thus, in both clinical and experimental practice, it is fundamental to have a reliable and objective method for its precise quantification. An image analysis algorithm was developed and validated for automatically and rapidly quantifying hepatic fat microvesicles. The image processing algorithms automatically segmented interstitial steatosis areas and analyzed the threshold region. Automatic quantifications did not significantly differ from manual evaluations of means of the same areas. Comparison of our image analysis quantifications with staging of histologic evaluations of liver steatosis presented significant correlations that are based on the distribution patterns and on the area quantity of steatosis, respectively. The use of algorithms for analysis and image processing is a sensitive, precise, objective and reproducible method of quantifying hepatic fat microvesicles, which complements semi-quantitative histologic evaluation systems.  相似文献   
29.
DNA fragmentation factor beta (DFFB) polypeptide, endonuclease G (EndoG), and Flap endonuclease-1 (FEN-1) are responsible for DNA fragmentation, a hallmark of apoptosis. Although the human homologs of these genes show three, four, and six nonsynonymous single-nucleotide polymorphisms (SNPs), respectively, data on their genotype distributions in populations worldwide are limited. In this context, the objectives of this study were to elucidate the genetic heterogeneity of all these SNPs in wide-ranging populations, and thereby to clarify the genetic background of these apoptosis-related endonucleases in human populations. We investigated the genotype distribution of their SNPs in 13 different populations of healthy Asians, Africans, and Caucasians using novel genotyping methods. Among the 13 SNPs in the 3 genes, only 3 were found to be polymorphic: R196K and K277R in the DFFB gene, and S12L in the EndoG gene. All 6 SNPs in the FEN-1 gene were entirely monoallelic. Although it remains unclear whether each SNP would exert any effect on endonuclease functions, these genes appear to exhibit low degree of genetic heterogeneity with regard to nonsynonymous SNPs. These findings allow us to conclude that human apoptosis-related endonucleases, similarly to other human DNase genes, revealed previously, are well conserved at the protein level during the course of human evolution.  相似文献   
30.
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