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排序方式: 共有1940条查询结果,搜索用时 15 毫秒
91.
Roua Hassoun Heidi Budde Hans Georg Mannherz Mria Ldi Setsuko Fujita-Becker Kai Thorsten Laser Anna Grtner Karin Klingel Desire Mhner Robert Stehle Innas Sultana Thomas Schaaf Mario Majchrzak Verena Krause Christian Herrmann Marc M. Nowaczyk Andreas Mügge Gabriele Pfitzer Rasmus R. Schrder Nazha Hamdani Hendrik Milting Kornelia Jaquet Diana Cimiotti 《International journal of molecular sciences》2021,22(17)
Rare pediatric non-compaction and restrictive cardiomyopathy are usually associated with a rapid and severe disease progression. While the non-compaction phenotype is characterized by structural defects and is correlated with systolic dysfunction, the restrictive phenotype exhibits diastolic dysfunction. The molecular mechanisms are poorly understood. Target genes encode among others, the cardiac troponin subunits forming the main regulatory protein complex of the thin filament for muscle contraction. Here, we compare the molecular effects of two infantile de novo point mutations in TNNC1 (p.cTnC-G34S) and TNNI3 (p.cTnI-D127Y) leading to severe non-compaction and restrictive phenotypes, respectively. We used skinned cardiomyocytes, skinned fibers, and reconstituted thin filaments to measure the impact of the mutations on contractile function. We investigated the interaction of these troponin variants with actin and their inter-subunit interactions, as well as the structural integrity of reconstituted thin filaments. Both mutations exhibited similar functional and structural impairments, though the patients developed different phenotypes. Furthermore, the protein quality control system was affected, as shown for TnC-G34S using patient’s myocardial tissue samples. The two troponin targeting agents levosimendan and green tea extract (-)-epigallocatechin-3-gallate (EGCg) stabilized the structural integrity of reconstituted thin filaments and ameliorated contractile function in vitro in some, but not all, aspects to a similar degree for both mutations. 相似文献
92.
Bernhard Kienesberger Beate Obermüller Georg Singer Barbara Mittl Reingard Grabherr Sigrid Mayrhofer Stefan Heinl Vanessa Stadlbauer Angela Horvath Wolfram Miekisch Patricia Fuchs Ingeborg Klymiuk Holger Till Christoph Castellani 《International journal of molecular sciences》2021,22(12)
We aimed to assess the in vitro antimicrobial activity and the in vivo effect on the murine fecal microbiome and volatile organic compound (VOC) profile of (S)-reutericyclin. The antimicrobial activity of (S)-reutericyclin was tested against Clostridium difficile, Listeria monocytogenes, Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Staphylococcus (S.) epidermidis, Streptococcus agalactiae, Pseudomonas aeruginosa and Propionibacterium acnes. Reutericyclin or water were gavage fed to male BALBc mice for 7 weeks. Thereafter stool samples underwent 16S based microbiome analysis and VOC analysis by gas chromatography mass spectrometry (GC-MS). (S)-reutericyclin inhibited growth of S. epidermidis only. Oral (S)-reutericyclin treatment caused a trend towards reduced alpha diversity. Beta diversity was significantly influenced by reutericyclin. Linear discriminant analysis Effect Size (LEfSe) analysis showed an increase of Streptococcus and Muribaculum as well as a decrease of butyrate producing Ruminoclostridium, Roseburia and Eubacterium in the reutericyclin group. VOC analysis revealed significant increases of pentane and heptane and decreases of 2,3-butanedione and 2-heptanone in reutericyclin animals. The antimicrobial activity of (S)-reutericyclin differs from reports of (R)-reutericyclin with inhibitory effects on a multitude of Gram-positive bacteria reported in the literature. In vivo (S)-reutericyclin treatment led to a microbiome shift towards dysbiosis and distinct alterations of the fecal VOC profile. 相似文献
93.
Thomsen C Knutsen HK Liane VH Frøshaug M Kvalem HE Haugen M Meltzer HM Alexander J Becher G 《Molecular nutrition & food research》2008,52(2):228-237
Very high concentrations of polybrominated diphenyl ethers (PBDE) have been reported in fish from Lake Mj?sa in Norway. This study was performed to examine the serum concentrations of PBDE and hexabromocyclododecane (HBCD) in consumers of fish from this lake and to investigate possible relationships between serum concentrations, self-reported fish intake and calculated total dietary PBDE exposure. Serum concentrations of the sum of the seven PBDE (BDE-28, 47, 99, 100, 153, 154 and 183) were significantly higher than those of a reference group of Norwegians eating only food with background levels of contamination (medians: 18 ng/g lipids men, 8.4 ng/g lipids women). The median dietary intake of Sum 7 PBDE was 2549 ng/day (30 ng/kg body weight/day), the highest dietary intake of PBDE reported. The contribution from fish caught from the contaminated lake comprised 98.7% of the total dietary exposure. For men, serum levels of PBDE were strongly correlated with the calculated dietary exposure, except for BDE-209. This suggests that sources other than the diet are important for human BDE-209 exposure. The median serum HBCD concentration was 4.1 and 2.6 ng/g lipids for men and women, respectively, and was also found to be associated with consumption of fish from Lake Mj?sa. 相似文献
94.
Hourly images registered by the Meteosat satellite are used to derive the global irradiance at ground level. Keeping almost the full spatial information of the original images, maps of irradiance characteristics for Africa are derived with a resolution of approx. 10 × 10 km2. Monthly irradiance conditions are characterized by means and standard deviations of daily sums and the irradiance of specific daytime hours. The data also allow for the extraction of irradiance time series for specific sites. In addition, the analysis of the spatial structure of the satellite-derived irradiance fields is used to identify regions in which the radiation characteristics call for special attention. 相似文献
95.
The peculiarities of meteorological wind potential in alpine settings compared to flatland and offshore sites are studied. Four data sources are used: Global reanalysis ERA40 from ECMWF, long‐term stations in the Tyrolean Alps, spatially dense measurements near the best site and Doppler sodar wind profiles. Due to the decrease of density with height, alpine sites suffer from a nearly linear decrease of harvestable power with altitude, which is more than offset by the increase of wind speed at altitudes above 1.5 km MSL. ERA40 data show higher potential on the northern than on the southern side of the Alps. The best locations are not isolated peaks but ridges within wide orographic channels. The best potential sites in the Tyrolean part of the Alps have median wind speeds of up to 7.1 m s?1 and extractable potentials between 2900 and 1600 kWh per year and per square meter of rotor area. The profile of horizontal wind speed at ridge sites is often not logarithmic but approximately constant within the height of a wind turbine due to a (nearly) complete absence of upwind fetch. Also, the turbulence intensity is independent of height. Icing can cause considerable downtimes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
96.
Georg Lutterschmid Matthias Stübner Rudi F. Vogel Ludwig Niessen 《Journal of the Institute of Brewing》2010,116(4):339-347
Malt‐induced gushing is a problem that has been known for many years. Mechanisms and inducing agents are still not fully understood and identified. Hydrophobins produced by various filamentous fungi are currently under discussion as biological gushing‐inducing compounds. In the current study the class II hydrophobin FcHyd5p, from the cereal pathogen Fusarium culmorum, was employed in beer and other carbonated beverages for gushing experiments and the influence of hop compounds on gushing potential was examined. It was demonstrated that this protein strongly induces gushing in various carbonated beverages, including beer. It was further demonstrated that the resulting gushing volume is susceptible to certain hop compounds and can be decreased significantly by the addition of these substances. 相似文献
97.
Zita Erika Madi Christian Brandes Georg Neumann David Quist Werner Ruppitsch Rupert Hochegger 《European Food Research and Technology》2013,237(2):125-135
The identification of both approved and non-approved genetically modified organisms (GMOs) is an integral part of GMO biosafety legislation in many countries. One aspect that may affect PCR-based detection of a GMO lies within the analysis of its genetic stability, as sequence alterations or DNA instabilities may impede quantification by PCR. Genetic stability can be analyzed using various methods, yet many of these methods have distinct disadvantages, including low sensitivity. In this study, high resolution melting (HRM) analysis and real-time PCR with Scorpion primers were used as a method to analyze the 3′ end of RR soybeans (RR 40-3-2) in a large number of samples (n = 1,034). No evidence for the occurrence of mutation events was found, implying that the nucleotide sequence of this region is unlikely to be unstable and is well suited as a target for the quantification of RR soybeans. Additionally, and as a preparative work for an optimization of the method, a 174 bp region of the first intron of the Adh1 gene was analyzed in several varieties of maize with different GMO events using the same approach. The results show that 2 alleles are present. In further experiments, the different alleles were cloned into plasmids to generate homozygous plasmids from heterozygous templates in order to generate for a more precise analysis. The overall methodological aim of these studies was to compare HRM analysis with Scorpion primer PCR. Both methods were capable of differentiating between the 2 homozygous and heterozygous alleles. For a better discrimination, however, we conclude that it is most reliable to consider the results of both methods. This dual approach is assumed to be an effective tool as an accurate, high-throughput means of the screening of GMOs for potential genetic instabilities that may interfere with the detection and identification of specific GM events. 相似文献
98.
Georg M. Weisz Lena Schneider Ute Schweiggert Dietmar R. Kammerer Reinhold Carle 《Innovative Food Science and Emerging Technologies》2010,11(4):733-741
A novel process for the production of light-colored sunflower protein isolates was developed, combining mild-acidic protein extraction with adsorptive removal of phenolic compounds. Four commercial food-grade adsorbent and three ion exchange resins were tested with regard to their affinity towards polyphenols. Amberlite™ XAD 16HP and FPX 66 showed optimal decolorization of the sunflower crude extracts. In contrast, ion exchange resins exerted maximal binding of monomeric phenolic compounds, but were less effective in removing colored compounds. Adsorption behavior of individual resins was assessed by adding resin to protein extracts varying the amounts of resin, protein concentration of the solutions and temperature. Furthermore, a D-optimal experimental design was applied to optimize adsorptive polyphenol removal from sunflower protein extracts using a styrene–divinylbenzene copolymer. Adsorption isotherms were determined for 5-O-caffeoylquinic acid and total phenolics, respectively. Optimal conditions were deduced from experiments at different temperatures, with different flow rates and extract concentrations. Finally, adsorbent and ion exchange resin columns were connected in series and successfully applied to produce light-colored sunflower protein on a pilot scale under the conditions optimized in laboratory experiments, thus demonstrating that this technology can easily be integrated into existing process lines.
Industrial relevance
A vital necessity to exploit novel protein sources arises from the increasing demand for human nutrition. Residues originating from sunflower oil production are rich in proteins and might serve as a source of plant proteins, which has not been valorized so far. This is due to their high contents of phenolic compounds that may interfere with the proteins lowering their nutritional value and impairing their sensory properties. Therefore, a process for mild-acidic protein extraction combining adsorption and ion exchanger technology for the removal of polyphenols from crude sunflower extracts was developed in the present study. 相似文献99.
100.