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41.
Shinichi Sunagawa Jens Roat Kultima Paul I Costea Aurélien Amiot Jürgen Böhm Francesco Brunetti Nina Habermann Rajna Hercog Moritz Koch Alain Luciani Daniel R Mende Martin A Schneider Petra Schrotz‐King Christophe Tournigand Jeanne Tran Van Nhieu Takuji Yamada Jürgen Zimmermann Vladimir Benes Matthias Kloor Cornelia M Ulrich Magnus von Knebel Doeberitz Iradj Sobhani Peer Bork 《Molecular systems biology》2014,10(11)
Several bacterial species have been implicated in the development of colorectal carcinoma (CRC),
but CRC-associated changes of fecal microbiota and their potential for cancer screening remain to be
explored. Here, we used metagenomic sequencing of fecal samples to identify taxonomic markers that
distinguished CRC patients from tumor-free controls in a study population of 156 participants.
Accuracy of metagenomic CRC detection was similar to the standard fecal occult blood test (FOBT) and
when both approaches were combined, sensitivity improved > 45% relative to the FOBT,
while maintaining its specificity. Accuracy of metagenomic CRC detection did not differ
significantly between early- and late-stage cancer and could be validated in independent patient and
control populations (N = 335) from different countries. CRC-associated
changes in the fecal microbiome at least partially reflected microbial community composition at the
tumor itself, indicating that observed gene pool differences may reveal tumor-related
host–microbe interactions. Indeed, we deduced a metabolic shift from fiber degradation in
controls to utilization of host carbohydrates and amino acids in CRC patients, accompanied by an
increase of lipopolysaccharide metabolism. 相似文献
42.
Liposomal delivery systems for water-soluble bioactives were prepared using the pro-liposome and the microfluidization technologies. Iron, an essential micronutrient as ferrous sulfate and ascorbic acid, as an antioxidant for iron were encapsulated in the liposomes. Liposomes prepared by the microfluidization technology using 6% (w/w) concentration of the lipid encapsulated with ferrous sulfate and ascorbic acid had particle size distributions around 150 to 200 nm, whereas liposomes from the pro-liposome technology resulted in particle sizes of about 5 μm. The encapsulation efficiency of ferrous sulfate was 58% for the liposomes prepared by the microfluidization using 6% (w/w) lipid and 7.5% of ferrous sulfate concentrations, and it was 11% for the liposomes from pro-liposome technology using 1.5% (w/v) lipid and 15% of ferrous-sulfate concentration. Both the liposomes exhibited similar levels of oxidative stability, demonstrating the feasibility of microfluidization-based liposomal delivery systems for large-scale food/nutraceutical applications. 相似文献
43.
44.
Pavlov E. D. Pavlov D. S. Ganzha E. V. Ruchiev M. A. Dien Tran Duc 《Journal of Ichthyology》2020,60(6):885-890
Journal of Ichthyology - The influence of urea and thiourea on the dynamics of the migration activity of climbing perch Anabas testudineus was studied. The exposure of climbing perch to 0.05%... 相似文献
45.
Dieu T. X. Nguyen Hung Tran Stefan Schwaiger Hermann Stuppner Stefania Marzocco 《化学与生物多样性》2021,18(1):e2000577
The extract of Elsholtzia ciliata aerial parts was subjected to bio-guided isolation using the intercellular ROS reduction in J774A.1 macrophages to monitor the anti-oxidative activity. Fifteen compounds were isolated from the active fractions including eleven flavonoids (vitexin, pedalin, luteolin-7-O-β-d -glucopyranoside, apigenin-5-O-β-d -glucopyranoside, apigenin-7-O-β-d -glucopyranoside, chrysoeriol-7-O-β-d -glucopyranoside, 7,3′-dimethoxyluteolin-6-O-β-d -glucopyranoside, luteolin, 5,6,4′-trihydroxy-7,3′-dimethoxyflavone, 5-hydroxy-6,7-dimethoxyflavone (compound 13 ), 5-hydroxy-7,8-dimethoxyflavone); three hydroxycinnamic acid derivatives (caffeic acid, 4-(E)-caffeoyl-l -threonic acid, 4-O-(E)-p-coumaroyl-l -threonic acid) and one fatty acid (α-linolenic acid). The biological evaluation of these compounds (10–2.5 μm ) indicated that all of them exerted good antioxidant and anti-inflammatory activities, in particular compound 13 . 相似文献
46.
47.
Yavuz Bülent Köse Gökalp İşcan Fatih Göger Gülşen Akalın Betül Demirci Kemal Hüsnü Can Başer 《化学与生物多样性》2016,13(10):1369-1379
The genus Centaurea L. is one of the largest and important genera of Asteraceae family. Centaurea species have been widely used as herbal remedies in folk medicine for their antidandruff, antidiarrheic, antirheumatic, anti‐inflammatory, choleretic, diuretic, digestive, stomachic, astringent, antipyretic, cytotoxic, and antibacterial properties. Centaurea baseri Kose & Alan is a recently described local endemic species in Turkey and this is the first study on the chemical composition and bioactivity of its hydrodistilled essential oil and the crude extract. According to chromatospectral analysis, hexadecanoic acid (42.3%), nonacosane (8.2%), and heptacosane (8.0%) were the main compounds of the essential oil, while 16 compounds were determined in the MeOH extract using LC/MS. Furthermore, antimicrobial, antioxidant, and cytotoxic effects of the essential oil and the extract were evaluated in comparison with the standard agents. The extract showed strong antifungal effect against Candida utilis at the concentration of 60 μg/ml (MIC) where the EO showed growth inhibition at the concentration of 47.00 μg/ml (MIC) against pathogen Bacillus cereus. Both the essential oil and the extract did not show any selective antioxidant properties. The extract showed remarkably selective cytotoxic properties against MCF‐7, PANC‐1, A549, and C6 glioma cells. 相似文献
48.
Relationships of diversity,disparity, and their evolutionary rates in squirrels (Sciuridae) 下载免费PDF全文
Miriam L. Zelditch Jingchun Li Lucy A. P. Tran Donald L. Swiderski 《Evolution; international journal of organic evolution》2015,69(5):1284-1300
Several theories predict that rapidly diversifying clades will also rapidly diverge phenotypically; yet, there are also reasons for suspecting that diversification and divergence might not be correlated. In the widely distributed squirrel clade (Sciuridae), we test for correlations between per lineage speciation rates, species richness, disparity, and a time‐invariant measure of disparity that allows for comparing rates when evolutionary modes differ, as they do in squirrels. We find that species richness and speciation rates are not correlated with clade age or with each other. Disparity appears to be positively correlated with clade age because young, rapidly diversifying Nearctic grassland clades are strongly pulled to a single stable optimum but older, slowly diversifying Paleotropical forest clades contain lineages that diverge along multiple ecological and morphological lines. That contrast is likely due to both the environments they inhabit and their phylogenetic community structure. Our results argue against a shared explanation for diversity and disparity in favor of geographically mediated modes of speciation and ecologically mediated modes of phenotypic evolution. 相似文献
49.
Oulehle Filip Wright Richard F. Svoboda Miroslav Bače Radek Matějka Karel Kaňa Jiří Hruška Jakub Couture Raoul-Marie Kopáček Jiří 《Ecosystems》2019,22(4):725-741
Ecosystems - Forest ecosystems worldwide are subjected to human-induced stressors, including eutrophication and acidification, and to natural disturbances (for example, insect infestation,... 相似文献
50.
Concentric photothermal coagulation with basket‐integrated optical device for treatment of tracheal stenosis 下载免费PDF全文
Van N. Tran Hyoung Shin Lee Van G. Truong Yun‐Hee Rhee Hyun Wook Kang 《Journal of biophotonics》2018,11(1)
A basket‐integrated optical device is developed to consistently treat tubular tissue by centering an optical diffuser in the lumen. Four nitinol arms in conjunction with the optical diffusing applicator are deployed to induce homogeneous circumferential light emission and concentric photothermal coagulation on tracheal tissue. A 1470‐nm laser light is employed for the tissue testing at various irradiation conditions and evaluated in terms of thermal gradient and temperature evolution. Preliminary experiments on liver tissue demonstrate the concentric development of the radial thermal coagulation in the tissue (eccentric ratio = ~5.5%). The interstitial tissue temperature increases with the total amount of energy delivery (around 65°C). Ex vivo trachea testing yields up to 16.5% tissue shrinkage due to dehydration as well as uniform ablation of the cilia and goblet cells in a mucosa layer under 7‐W irradiation for 10 s. The proposed optical device may be a feasible therapeutic method to entail the circumferential coagulation in the tubular tissues in a reliable manner. 相似文献