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101.
An extraction apparatus was equipped with a nitrogen-flushing vessel to purge volatiles from a 10-g miso prepared solution at 40 degrees C, a reflux condenser to recover water, a coiled cold-trap to separate ethanol in advance, and a glass-lined stainless (GLS) trap filled with Tenax TA for flavor adsorption. Volatiles in the GLS tube were released with a thermal desorption device and condensed with a Micro-cryo trap prior to connection with GC and GC-MS for characterization. After analysis, a broad volatile profile comprising 9 categories of functional group and 97 identified compounds was achieved. As affected by ethanol supplementation for miso fermentation, most volatiles except alcohols and acetals in the low-salt products fermented with 5% NaCl and 7.5% ethanol were higher than those in the control products fermented with 9% NaCl and 0% ethanol and the high-ethanol supplemented products fermented with 5% NaCl and 15% ethanol. It reveals that supplementation of ethanol in miso at an appropriate level not only enabled a low-salt miso fermentation but also enhanced flavor formation.  相似文献   
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To estimate the seroprevalence of Dirofilaria immitis infection in domestic dogs in Taiwan, we utilized a commercial ELISA kit (Snap, IDEXX, USA) for detecting circulating antigens released by adult female worms. Serum specimens of 664 domestic dogs sampled from Taipei City in northern Taiwan and 14 mountain aboriginal districts in eastern Taiwan were screened for D. immitis antigens. Multivariate-adjusted odds ratios (ORs) with their 95% confidence intervals (CIs) were estimated by multiple logistic regression analysis. A total of 89 subjects were antigen-positive, giving a seroprevalence of 13.4%, of which the seroprevalence in Taipei City and mountain aboriginal districts were 13.8 and 12.1%, respectively. The mean overall seropositive rates were 6.3% in 1-3-year-old age group, 14.1% in 3-6-year-old age group and 23.7% in the > or =6-year-old age group. The older the age, the higher the seroprevalence (OR=4.6, 95% CI=2.4-9.0 for the > or =6-year-old age group versus 1-3-year-old age group, P<0.001) for all the dogs in the present study. Moreover, seroprevalence was not different between female and male dogs in either Taipei City or mountain aboriginal districts (P>0.05). Also, no significant difference in seroprevalence among dogs between the two geographical areas was found (P>0.05). In the logistic regression analysis, the seroprevalence of D. immitis remained significantly increased with age after multivariate adjustment in the present study. To our knowledge, this is the first report on the status of D. immitis infection in domestic dogs in Taipei City and mountain aboriginal districts in Taiwan to date.  相似文献   
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As a folk medicine, the hot-water infusion of water caltrop fruits has been used to protect the liver. In this study, the outer skins of mature water caltrop fruits ( Trapa taiwanensis Nakai) were removed, forced-air-dried, pulverized, and subjected to extraction with hot water, and the infusion was lyophilized and pulverized to prepare a hot water extract of T. taiwanensis (HWETT). HWETT was subjected to assays of α,α-diphenyl-β-picrylhydrazyl scavenging activity, reducing power, Trolox equivalent antioxidant capacity, and antioxidative potency, and all determinations showed HWETT to be a potent antioxidant. As further analyzed with LC-MS, two major HPLC-detected components were elucidated as gallic acid and ellagic acid. Hepatoprotective activity of HWETT was assessed with Sprague-Dawley male rats by oral administration. Six groups of rats (n = 8 for each) were respectively treated, namely, control, CCl(4) (20% CCl(4)/olive oil by 2.0 mL/kg bw), CCl(4) and Silymarin (200 mg/kg bw), CCl(4) and low HWETT dose (12.5 mg/kg bw), CCl(4) and medium HWETT dose (25 mg/kg bw), and CCl(4) and high HWETT dose (125 mg/kg bw). After 8 weeks, all animals were fasted for an additional day and sacrificed to collect blood, liver, and kidney for analyses. Histopathological examinations showed that oral administrations with Silymarin and HWETT were effective in protecting the liver from CCl(4)-caused fatty change. Oral administration of HWETT at 125 mg/kg bw was more effective than was Silymarin at 200 mg/kg bw. On biochemical analyses, oral administrations with HWETT at medium and high doses were effective (p < 0.05) in lowering CCl(4)-caused increases of alanine aminotransferase and aspartate aminotransferase activities. It is of merit to demonstrate HWETT as a potent source of antioxidants and hepatoprotective agents.  相似文献   
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Inflammatory bowel diseases have been a risk factor of colorectal cancer (CRC). The reactive oxygen species (ROS) generated by inflammatory cells create oxidative stress and contribute to neoplastic transformation, proliferation, and even metastasis. Previously, resveratrol (RS) and pterostilbene (PS) had been reported to prevent chemical-induced colon carcinogenesis by anti-inflammatory and pro-apoptotic properties. In this study, we investigated whether RS and PS could prevent the azoxymethane (AOM)-induced colon tumorigenesis via antioxidant action and to explore possible molecular mechanisms. Male BALB/c mice were injected with AOM (5 mg/kg of body weight) with or without RS or PS, and at the end of the protocol, all of the mice were euthanized and colons were analyzed. Administrations of PS can be more effective than RS in reducing AOM-induced formation of aberrant crypt foci (ACF), lymphoid nodules (LNs), and tumors. We also find that PS is functioning more effectively than RS to reduce nuclear factor-κB (NF-κB) activation by inhibiting the phosphorylation of protein kinase C-β2 (PKC-β2) and decreasing downstream target gene expression, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and aldose reductase (AR) in mouse colon stimulated by AOM. Moreover, administration of RS and PS for 6 weeks significantly enhanced expression of antioxidant enzymes, such as heme oxygenase-1 (HO-1) and glutathione reductase (GR), via activation of NF-E2-related factor 2 (Nrf2) signaling. When the above findings are taken together, they suggest that both stilbenes block cellular inflammation and oxidative stress through induction of HO-1 and GR, thereby preventing AOM-induced colon carcinogenesis. In comparison, PS was a more potent chemopreventive agent than RS for the prevention of colon cancer. This is also the first study to demonstrate that PS is a Nrf2 inducer and AR inhibitor in the AOM-treated colon carcinogenesis model.  相似文献   
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An Archean Geomagnetic Reversal in the Kaap Valley Pluton, South Africa   总被引:1,自引:0,他引:1  
The Kaap Valley pluton in South Africa is a tonalite intrusion associated with the Archean Barberton Greenstone Belt. Antipodal paleomagnetic directions determined from the central and marginal parts of the pluton record a geomagnetic reversal that occurred as the pluton cooled. The age of the reversal is constrained by an 40Ar/39Ar plateau age from hornblende at 3214 +/- 4 million years, making it the oldest known reversal. The data presented here suggest that Earth has had a reversing, perhaps dipolar, magnetic field since at least 3.2 billion years ago.  相似文献   
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In the interest of developing a simple and rapid ultraweak chemiluminescence assay for assessing the superoxide (O(2)(-))-scavenging activities of various aqueous extracts of food constituents, a specific and stable O(2)(-)-generating system was sought. Reported herein is the obtainment for the first time of a specific and stable O(2)(-)-generating system consisting of methylglyoxal (MG), a reactive 2-oxo aldehyde and arginine, which has been shown to produce much steadier lucigenin-based chemiluminesence (LBCL) than the conventional xanthine/xanthine oxidase system running in parallel and monitoring by an ultraweak chemiluminescence analyzer. Upon mixing of MG and arginine in a phosphate-buffered saline solution, pH 7.4, steady, time-dependent increments of LBCL can be visually observed. The plateau of LBCL can be reached in approximately 10 min and retained in a steadily stable state thereafter without fluctuation for the next 15 min. The lucigenin-based LBCL generation was shown to be specific since it could be effectively inhibited by active bovine SOD, but not by heat-inactivated enzyme or catalase. Conversely, the xanthine/xanthine oxidase system can merely produce a LBCL peak rapidly but decay instantaneously. To illustrate the application of the proposed method for assessing the O(2)(-)-scavenging ability of various food extracts, namely, Prunus mume (A), Lilum lancifolium (B), Creataegus pinnatifida (C), Tremella fuciformis (D), Fortunella margarita (E), and Scutellaria baicalensis (F), we used the following protocol: 12 min after monitoring of LBCL, 1 mg/mL of each of the test compounds was added to the assay system and various degrees of sudden drop of LBCL values were observed, indicating differences in O(2)(-)-scavenging abilities exerted by these food extracts that can be visually compared. Consequently, the percentages of inhibition of LBCL versus the concentrations of a test compound can be constructed. It follows that the concentration needed to inhibit 50% of LBCL (IC(50)) of a test compound can be extrapolated from the curve. Using this approach, we were able to obtain the IC(50) values of various compounds to be tested and the order of inhibitory efficiency of the above-mentioned food extracts was ranked, being A > B > C > D > E > F, respectively.  相似文献   
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