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71.
Recent studies have shown that dietary phospholipids, especially phosphatidylcholine and phosphatidylserine, have various beneficial biological effects. However, there are not enough data concerning the physiological function of dietary phosphatidylinositol (PI). The metabolic syndrome, a cluster of metabolic abnormalities such as dyslipidemia, diabetes mellitus, and hypertension, is a widespread and increasingly prevalent disease in industrialized countries. Nonalcoholic fatty liver disease (NAFLD) is often associated with features of the metabolic syndrome. NAFLD describes the spectrum of liver damage ranging from hepatic steatosis to steatohepatitis, liver fibrosis, and cirrhosis, and it is emerging as the most common liver disease worldwide. The present study examined whether dietary PI protects Zucker ( fa/ fa) rats from the metabolic syndrome. For 4 weeks, rats were fed semisynthetic diets containing either 7% soybean oil or 5% soybean oil plus 2% PI. Dietary PI markedly prevented the development of hepatomegaly and hepatic steatosis and lowered hepatic injury markers in serum. Additionally, hyperinsulinemia was relieved by the feeding of dietary PI in Zucker rats. These effects were attributable to an increase in serum adiponectin, enhancement of fatty acid beta-oxidation, and suppression of mRNA expression of inflammatory genes in the liver. This is the first report that dietary PI increases serum adiponectin level and prevents the development of NAFLD in a rat model of the metabolic syndrome.  相似文献   
72.
There is strong evidence that oxidative stress participates in the etiology of neurodegenerative diseases such as Parkinson's, and Alzheimer's diseases. Moreover, emotional stress effects in the central nervous system play a vital role in homeostasis. The protective effect of anthocyanins on the cerebral oxidative stress was studied using the whiskers cut model. In mice, such treatment causes psychological or emotional distress leading to oxidative stress in tissues. To investigate the in vivo antioxidant activity of anthocyanins, an extract of Vaccinium myrtillis L., an anthocyanin mixture, was orally administered (100 mg/kg of body weight.) to mice for 7 days, and then psychological stress was assessed by cutting off their whiskers. Whisker removal increased both protein carbonyl formation and lipid peroxidation in the brain, heart, kidney, and liver. Further, the levels of oxidative markers showed regional differences in the brain. Concomitantly, dopamine neurotransmitter levels were altered in both the midbrain and the brain cortex. Orally administered anthocyanins were also active in the brain, suppressing stress-induced cerebral oxidative stress and dopamine abnormalities in distressed mice. These effects of anthocyanin treatment suggest their possible usefulness for the treatment of cerebral disorders related to oxidative stress.  相似文献   
73.
Decades of intensive off‐road vehicle use for border security, immigration, smuggling, recreation, and military training along the USA–Mexico border have prompted concerns about long‐term human impacts on sensitive desert ecosystems. To help managers identify areas susceptible to soil erosion from anthropogenic activities, we developed a series of erosion potential models based on factors from the Universal Soil Loss Equation (USLE). To better express the vulnerability of soils to human disturbances, we refined two factors whose categorical and spatial representations limit the application of the USLE for non‐agricultural landscapes: the C‐factor (vegetation cover) and the P‐factor (support practice/management). A soil compaction index (P‐factor) was calculated as the difference in saturated hydrologic conductivity (Ks) between disturbed and undisturbed soils, which was then scaled up to maps of vehicle disturbances digitized from aerial photography. The C‐factor was improved using a satellite‐based vegetation index, which was better correlated with estimated ground cover (r2 = 0·77) than data derived from land cover (r2 = 0·06). We identified 9,780 km of unauthorized off‐road tracks in the 2,800‐km2 study area. Maps of these disturbances, when integrated with soil compaction data using the USLE, provided landscape‐scale information on areas vulnerable to erosion from both natural processes and human activities and are detailed enough for adaptive management and restoration planning. The models revealed erosion potential hotspots adjacent to the border and within areas managed as critical habitat for the threatened flat‐tailed horned lizard and endangered Sonoran pronghorn. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
74.
Based on chemical and mechanical compositions and quartz content of red and/or yellow colored soil materials in the southwestern part of Japan, lithology index (LI) and weathering index (WI) were derived using a multivariate statistical method (factor analysis). The variables used for factor analysis are Fe2O3/Al2O3, TiO2/Al2O3, Fe2O3+Al2O3+Quartz, Si(non-quartz)/(Fe2O3 + Al2O3), CaO + MgO + K2O3, MgO/K2O3 and Quartz/Sand, all of which represent certain different aspects of weathering and/or Iithological characteristics. Since LI and WI are mutually independent, it is possible to evaluate the effect of the degree of weathering on the characteristics of red and/or yellow colored soil materials independently from that of lithology.  相似文献   
75.
1-deoxynojirimycin (DNJ), a potent glucosidase inhibitor, is a characteristic constituent of the mulberry leaf. Dietary mulberry DNJ may be beneficial for the suppression of abnormally high blood glucose levels, thereby preventing diabetes mellitus. Although there is considerable interest in the effects of mulberry DNJ, the intestinal absorption and pharmacokinetic profile of orally administered mulberry DNJ have never been characterized. In this study, we developed a method for determining the level of plasma DNJ by hydrophilic interaction chromatography coupled to a mass spectrometric detector (HILIC-MS) to investigate the absorption and metabolism of orally administered mulberry DNJ in rats. DNJ was separated from plasma extract on a TSK gel Amide-80 column, a representative column for HILIC. At postcolumn, DNJ was concurrently detected and identified by MS. The plasma DNJ concentration in fasted rats was below the detection limit [<1 microg (6 nmol)/mL]; however, the concentration reached a maximum [15 microg (92 nmol)/mL] 30 min after the administration of mulberry DNJ (110 mg/kg of body weight), and the DNJ concentration decreased rapidly thereafter. When the rats received different amounts of mulberry DNJ (1.1, 11, and 110 mg/kg of body weight), dose-dependent incorporation of DNJ into the plasma was confirmed. We did not detect any DNJ metabolites in the plasma. These findings indicate that orally administered mulberry DNJ is absorbed as an intact form from the alimentary tract and then is quickly excreted from the body. The developed HILIC-MS method could be applied in determining levels of DNJ in urine and tissues, and therefore, the method would be a powerful tool for studying the metabolic fate of mulberry DNJ as well as its bioavailability.  相似文献   
76.
Immunoglobulin M (IgM) is known as a main factor in the humoral immune system of teleosts. In the present study, the effect of cortisol on plasma IgM concentrations was investigated using a specific antibody to IgM in masu salmon (Oncorhynchus masou). Cortisol was orally administered each day for 2 weeks at a dose of 1 mg g−1 in the diet, and for the following week the fish were fed a non-treated diet. Blood plasma samples were collected at 0, 1, 2 and 3 weeks after the initiation of treatment. Oral administration of cortisol elevated plasma cortisol concentrations to about 40 ng/ml for 2 weeks after administration and slightly reduced plasma IgM concentration; the suppression was statistically significant one week after the period of hormone administration. However, treatment with cortisol did not affect plasma concentrations of total protein or α1-protein, one of the major serum proteins, during the experimental period. These results indicate that cortisol specifically suppresses plasma IgM concentrations.  相似文献   
77.
Chemical investigations of the Egyptian soft coral Sarcophyton ehrenbergi have led to the isolation of compounds 1–3 as well as the previously reported marine cembranoid diterpene sarcophine (4). Structures were elucidated by comprehensive NMR and HRMS experimentation. Isolated compounds were in vitro assayed for cytotoxic activity against human hepatocarcinoma (HepG2) and breast adenocarcinoma (MCF-7) cell lines.  相似文献   
78.
Kazakhstan is the largest landlocked country and contains two important propagation routes for livestock from the Fertile Crescent to Asia. Therefore, genetic information about Kazakhstani cattle can be important for understanding the propagation history and the genetic admixture in Central Asian cattle. In the present study, we analyzed the complete mtDNA D‐loop sequence and SRY gene polymorphism in 122 Kazakhstani native cattle. The D‐loop sequences revealed 79 mitochondrial haplotypes, with the major haplogroups T and I. The Bos taurus subhaplogroups consisted of T (3.3%), T1 (2.5%), T2 (2.5%), and T4 (0.8%) in addition to the predominant subhaplogroup T3 (86.9%), and the Bos indicus subhaplogroup of I1 (4.1%). Subsequently, we investigated the paternal lineages of Bos taurus and Bos indicus, however, all Kazakhstani cattle were shown to have Y chromosome of Bos taurus origin. While highly divergent mtDNA subhaplogroups in Kazakhstani cattle could be due to the geographical proximity of Kazakhstan with the domestication center of the Fertile Crescent, the absence of Bos indicus Y chromosomes could be explained by a decoupling of the introgression dynamics of maternal and paternal lineages. This genetic information would contribute to understanding the genetic diversity and propagation history of cattle in Central Asia.  相似文献   
79.
In our previous study, we performed genome‐wide association study (GWAS) to identify the genomic region associated with Fat area ratio to rib eye area (FAR) and detected a candidate in BTA7 at 10–30 Mbp. The present study aims to comprehensively detect all polymorphisms in the candidate region using whole‐genome resequencing data. Based on whole‐genome resequencing of eight animals, we detected 127,090 polymorphisms within the region. Of these, 31,945 were located within the genes. We further narrowed the polymorphisms to 6,044 with more than five allele differences between the high and low FAR groups that were located within 179 genes. We subsequently investigated the functions of these genes and selected 170 polymorphisms in eight genes as possible candidate polymorphisms. We focused on SLC27A6 K81M as a putative candidate polymorphism. We genotyped the SNP in a Japanese Black population (n = 904) to investigate the effect on FAR. Analysis of variance revealed that SLC27A6 K81M had a lower p‐value (p = .0009) than the most significant SNP in GWAS (p = .0049). Although only SLC27A6 K81M was verified in the present study, subsequent verification of the remaining candidate genes and polymorphisms could lead to the identification of genes and polymorphisms responsible for FAR.  相似文献   
80.
Fine root biomass can be estimated from the quantity of DNA of a target plant extracted from fine root samples using regression analysis. However, the application of this method to fine root samples mixed with soil particles (mixed samples) is difficult due to the high DNA adsorption capacity of some clay minerals. Our aim in this study was to clarify the enhancement level of the DNA extraction efficiency of an improved method, and to obtain a regression line between the amount of DNA and the root biomass from a mixed sample with similar reliability as for fine roots alone (pure root sample). We examined the amount of DNA extracted from a mixture of Zea mays L. fine roots and highly adsorbent Kanuma soil using various concentrations of a skim milk solution, which acts as an adsorption competitor for the soil particles during the DNA extraction process. The amount of DNA of Zea mays extracted from the mixed sample using 0% skim milk was lower than from the pure root sample. However, the amount of DNA extracted from the mixed sample increased with increasing concentrations of skim milk, reaching the same level as for the pure root samples and resulting in a regression line that was similar to the pure root samples. Optimal DNA extraction levels were obtained with the addition of 20?µL of a 20% skim milk solution to 30?mg of a mixed sample. We also discuss the applicability of this method to other plant species and soil types.  相似文献   
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