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Yuan Yang Lake (YYL), Taiwan, experiences both winter and typhoon-initiated mixing, and each type of mixing event is characterized
by contrasting environmental conditions. Previous work suggested that after typhoon mixing, bacterial communities in YYL reset
to a pioneer composition and then follow a predictable trajectory of change until the next typhoon. Our goal was to continue
this investigation by observing bacterial community change after a range of mixing intensities, including seasonal winter
mixing. We fingerprinted aquatic bacterial communities in the epilimnion and hypolimnion using automated ribosomal intergenic
spacer analysis and then assessed community response using multivariate statistics. We found a significant linear relationship
between water column stability and the epilimnion to hypolimnion divergences. In comparison to the summer, we found the winter
community had a distinct composition and less variation. We divided the bacterial community into population subsets according
to abundance (rare, common, or dominant) and occurrence (transient or persistent) and further explored the contribution of
these subsets to the overall community patterns. We found that transient taxa did not drive bacterial community patterns following
weak typhoon mixing events, but contributed substantially to patterns observed following strong events. Common taxa generally
did not follow the community trajectory after weak or strong events. Our results suggest intensity, frequency, and seasonality
jointly contribute to aquatic bacterial response to mixing disturbance. 相似文献
22.
Antioxidant activities and phytochemical characteristics of extracts from Acacia confusa bark 总被引:2,自引:0,他引:2
The present study was carried out to evaluate the antioxidant activities of bark extract of Acacia confusa and some of the isolated constituents from its ethyl acetate (EtOAc) fraction in various in vitro systems to gain mechanistic insights. Results from antioxidant assays together with authentic antioxidant standards revealed that EtOAc fraction showed strong superoxide radical scavenging activity, reducing power, and ferrous ion-chelating ability. Following an in vitro antioxidant activity-guided fractionation procedure, 16 constituents including 12 benzoic acids, three cinnamic acids and one lignans were isolated and identified from the EtOAc fraction. We also evaluated the structure-activity relationships of benzoic and cinnamic acid derivatives. Results obtained indicated that the bark extracts and the derived phytochemicals from A. confusa have a great potential to prevent disease caused by the overproduction of radicals and also it might be used as a potential source of natural antioxidant agent. 相似文献
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Tai-Yi Hsu Hong-Mo Shih Yu-Chiao Wang Leng-Chieh Lin Guan-Yi He Chih-Yu Chen Chia-Hung Kao Chao-Hsien Chen Wei-Kung Chen Tse-Yen Yang 《PloS one》2016,11(11)
PurposeThis study investigated whether alcoholic intoxication (AI) increases the risk of inflammatory bowel disease (IBD) by using a population-based database in Taiwan.MethodsThis retrospective matched-cohort study included 57 611 inpatients with new-onset AI (AI cohort) and 230 444 randomly selected controls (non-AI cohort). Each patient was monitored for 10 years to individually identify those who were subsequently diagnosed with Crohn disease (CD) and ulcerative colitis (UC) during the follow-up period. Cox proportional hazard regression analysis was conducted to determine the risk of IBD in patients with AI compared with controls without AI.ResultsThe incidence rate of IBD during the 10-year follow-up period was 2.69 per 1 000 person-years and 0.49 per 1 000 person-years in the AI and non-AI cohorts, respectively. After adjustment for age, sex, and comorbidity, the AI cohort exhibited a 3.17-fold increased risk of IBD compared with the non-AI cohort (hazard ratio [HR] = 3.17, 95% confidence interval [CI] = 2.19–4.58). Compared with the non-AI cohort, the HRs of CD and UC were 4.40 and 2.33 for the AI cohort, respectively. After stratification for the severity of AI according to the duration of hospital stay, the adjusted HRs exhibited a significant correlation with the severity; the HRs of IBD were 1.76, 6.83, and 19.9 for patients with mild, moderate, and severe AI, respectively (p for the trend < .0001).ConclusionThe risk of IBD was higher in patients with AI and increased with the length of hospital stay. 相似文献
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Lipids were extracted by a supercritical fluid extraction method from 10 species of filamentous red algae obtained from culture
collections and their fatty acid compositions were determined. The fatty acid profiles of the 10 species were similar. The
major fatty acids were 16:0, 20:4ω6 and 20:5ω3 (eicosapentaenoic acid, EPA), which amounted to over 70% of the total fatty
acids. The highest EPA content (29.8 mg/L), as a percentage of total fatty acids, was produced by Liagora boergesenii filaments, which has good potential for EPA mass production in pilot plants. 相似文献
25.
Chih-Yu Lo Lin-Chen Hsu Min-Shin Chen Yi-Jing Lin Lih-Geeng Chen Cheng-Deng Kuo Jin-Yi Wu 《Bioorganic & medicinal chemistry letters》2013,23(1):305-309
To alter its hydrophobicity, a series of compounds bearing 9-O-alkyl- or 9-O-terpenyl- substituted berberine were synthesized and evaluated for anticancer activity against human cancer HepG2 and HT29 cell lines. We found that the lipophilic substitute of 9-O-alkyl- and 9-O-terpenyl berberine derivatives plays a role in inhibiting the human cancer cell growth and its activity could be maximized with the optimized substitute type and chain length. Most strikingly, nonetheless, of the six compounds prepared, sample 8, a farnesyl 9-O-substituted berberine, showed either comparable or better cytotoxic activity against human cancer HepG2 cell line than that of berberine. Compound 8 had also shown a 104-fold antiproliferation activity in compare with berberine against human hepatoma HepG2 cell lines after 48 incubation hours. Further, in Hoechst 33258 and annexin V-FITC/PI staining analyses it induced apoptosis in HepG2 cells at lower concentration than that of berberine for 24 h. Take all; farnesyl 9-O-substituted berberine could be a potential candidate for new anticancer drug development. 相似文献
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Chih-Cheng Lin Hsiu-Hua Lin Hsiang Chang Lu-Te Chuang Chih-Yu Hsieh Shing-Hwa Lu Chi-Feng Hung Jia-Feng Chang 《Current issues in molecular biology》2022,44(9):3980
Polyphenols and flavonoids from non-fermented green tea and fully-fermented black tea exhibit antioxidant abilities that function as natural health foods for daily consumption. Nonetheless, evidence regarding prophylactic effects of purple shoot tea on immunomodulation remains scarce. We compared the immunomodulatory effects of different tea processes on oxidative stress and cytokine expressions in lipopolysaccharide (LPS)-stimulated macrophages. Major constituents of four tea products, Taiwan Tea Experiment Station No.12 (TTES No. 12) black and green tea and purple shoot black and purple shoot green tea (TB, TG, PB and PG, respectively), were analyzed to explore the prophylactic effects on expressions of free radicals, nitric oxide (NO), monocyte chemoattractant protein-1 (MCP-1), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) in LPS-activated RAW264.7 cell models. PG contained abundant levels of total polyphenols, flavonoids, condensed tannins and proanthocyanidins (371.28 ± 3.83; 86.37 ± 1.46; 234.67 ± 10.1; and 24.81 ± 0.75 mg/g, respectively) contributing to excellent free radical scavenging potency. In both the LPS-activated inflammation model and the prophylactic model, all tea extracts suppressed NO secretion in a dose-dependent manner, especially for PG. Intriguingly, most tea extracts enhanced expressions of IL-6 in LPS-stimulated macrophages, except PG. However, all teas disrupted downstream transduction of chemoattractant MCP-1 for immune cell trafficking. In the prophylactic model, all teas inhibited inflammatory responses by attenuating expressions of IL-6 and TNF-α in a dose-dependent manner, especially for TG and PG. Our prophylactic model demonstrated PG exerts robust effects on modulating LPS-induced cytokine expressions of MCP-1, IL-6 and TNF-α through scavenging free radicals and NO. In light of the prophylactic effects on LPS-related inflammation, PG effectively scavenges free radicals to modulate cytokine cascades that could serve as a functional beverage for immunomodulation. 相似文献
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SUMMARY: DNA polymorphism detector (DPD) is a new web application developed to help automate the process of cDNA clone validation. DPD identifies and highlights discrepancies between any cDNA clone sequence and its expected reference sequence. To determine if these differences correspond to natural genetic polymorphisms (versus artifacts introduced during clone production or evaluation), DPD uses the discrepancies, along with flanking sequences, to search GenBank for identical matching strings. If matching DNA sequences are found, DPD verifies that they are from the same gene. The application then reports the discrepancy as a polymorphism along with the corresponding GenBank reference information. AVAILABILITY: DPD is currently hosted by the Harvard Institute of Proteomics at http://www.hip.harvard.edu 相似文献
30.
Hang-Lung Chang Chih-Yu Chen Ya-Fen Hsu Wen-Shin Kuo George Ou Pei-Ting Chiu Yu-Han Huang Ming-Jen Hsu 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013