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71.
Manfred Lamprecht Simon Bogner Gert Schippinger Kurt Steinbauer Florian Fankhauser Seth Hallstroem Burkhard Schuetz Joachim F Greilberger 《Journal of the International Society of Sports Nutrition》2012,9(1):1-13
Background
Probiotics are an upcoming group of nutraceuticals claiming positive effects on athlete??s gut health, redox biology and immunity but there is lack of evidence to support these statements.Methods
We conducted a randomized, double-blinded, placebo controlled trial to observe effects of probiotic supplementation on markers of intestinal barrier, oxidation and inflammation, at rest and after intense exercise. 23 trained men received multi-species probiotics (1010 CFU/day, Ecologic?Performance or OMNi-BiOTiC?POWER, n?=?11) or placebo (n?=?12) for 14?weeks and performed an intense cycle ergometry over 90 minutes at baseline and after 14?weeks. Zonulin and ??1-antitrypsin were measured from feces to estimate gut leakage at baseline and at the end of treatment. Venous blood was collected at baseline and after 14?weeks, before and immediately post exercise, to determine carbonyl proteins (CP), malondialdehyde (MDA), total oxidation status of lipids (TOS), tumor necrosis factor-alpha (TNF-??), and interleukin-6 (IL-6). Statistical analysis used multifactorial analysis of variance (ANOVA). Level of significance was set at p?<?0.05, a trend at p?<?0.1.Results
Zonulin decreased with supplementation from values slightly above normal into normal ranges (<30?ng/ml) and was significantly lower after 14?weeks with probiotics compared to placebo (p?=?0.019). We observed no influence on ??1-antitrypsin (p?>?0.1). CP increased significantly from pre to post exercise in both groups at baseline and in the placebo group after 14?weeks of treatment (p?=?0.006). After 14?weeks, CP concentrations were tendentially lower with probiotics (p?=?0.061). TOS was slightly increased above normal in both groups, at baseline and after 14?weeks of treatment. There was no effect of supplementation or exercise on TOS. At baseline, both groups showed considerably higher TNF-?? concentrations than normal. After 14?weeks TNF-?? was tendentially lower in the supplemented group (p?=?0.054). IL-6 increased significantly from pre to post exercise in both groups (p?=?0.001), but supplementation had no effect. MDA was not influenced, neither by supplementation nor by exercise.Conclusions
The probiotic treatment decreased Zonulin in feces, a marker indicating enhanced gut permeability. Moreover, probiotic supplementation beneficially affected TNF-?? and exercise induced protein oxidation. These results demonstrate promising benefits for probiotic use in trained men.Clinical trial registry
http://www.clinicaltrials.gov, identifier: NCT01474629 相似文献72.
73.
Xiuqin Zhang Konrad Schneider Guoming Liu Jianhong Chen Karsten Brüning Dujin Wang Manfred Stamm 《Polymer》2012,53(2):648-656
Cavitation and superstructure evolution of polymers during stretching play crucial roles to influence the mechanical properties of materials. In this study, we investigated deformation-mediated superstructures and cavitation of poly (l-lactide) (PLA) as well as their dependence on stretching temperatures by in-situ small-angle X-ray (SAXS) analysis coupled with mechanical testing. It is found that the cavitation and crystalline deformation are strongly influenced by stretching stress during deformation, which significantly depends on the stretching temperature. At lower stretching temperature (70 °C), the cavitation is initiated before the yielding and then stimulates the crystallite shearing. At higher stretching temperature (90 °C), however, the crystallites shear firstly and then crystalline deformation promotes the formation of cavities orientated along the stretching direction. High stretching temperature benefits the formation of relatively perfect crystals with high orientation. The results provide the basic knowledge of how to adjust the mechanical properties of polymer materials by controlling their superstructure in the deformation process. 相似文献
74.
Hermann Kreyenschulte Sven Richter Thomas Götze Dieter Fischer Dagmar Steinhauser Manfred Klüppel Gert Heinrich 《Carbon》2012,50(10):3649-3658
The interactions of the ionic liquid 1-allyl-3-methyl-imidazolium chloride (AMIMCl) with different grades of carbon black have been investigated using rheological measurements, differential scanning calorimetry and Raman spectroscopy. We could prove strong attractive interactions of AMIMCl with the carbon black surface, which result, for example, in the formation of an AMIMCl–carbon black–bucky gel and in an increased glass transition temperature of the ionic liquid in the presence of carbon black. Raman spectroscopy revealed that the AMIMCl is preferably attached to the edges of graphitic crystals at the carbon black surface, which have the highest adsorption energies. A surface treatment of different grades of carbon black with AMIMCl led to significant changes of the mechanical and electrical properties of different rubber compounds filled with carbon black, which can be attributed to a decreased filler–polymer interaction and a local plasticising effect of the AMIMCl at the carbon black surface. 相似文献
75.
Stolfa DA Stefanachi A Gajer JM Nebbioso A Altucci L Cellamare S Jung M Carotti A 《ChemMedChem》2012,7(7):1256-1266
Epigenetic regulation is an essential process for the normal functioning of genes. Therefore, targeting epigenetic dysregulation in cancer may be a valid therapeutic approach for the treatment of this severe disease. Histone deacetylases (HDACs) are enzymes involved in the regulation of epigenetic post-translational modifications; because they are overexpressed in many types of cancer, HDACs are valuable targets for the development of new anticancer agents. A large series of 2-aminobenzanilides linked at the 4'-position to α-amino acid amides, arenes, and heteroarenes through a methylene bridge were designed, synthesized, and tested as novel HDAC inhibitors. Several compounds showed IC(50) values in the two-digit nanomolar range in hrHDAC1 inhibition assays, lower than that of the reference compound MS-275. They also showed interesting selectivity profiles, as confirmed by western blot assays. 相似文献
76.
Lux J Peña EJ Bolze F Heinlein M Nicoud JF 《Chembiochem : a European journal of chemical biology》2012,13(8):1206-1213
The design, preparation and characterisation of a library of malachite green (MG) derivatives for two-photon RNA labelling is described. Some of these MG derivatives exhibit an increased affinity for an MG-aptamer, as well as improved two-photon sensitivity when compared to the classical malachite green chloride. The underlying mechanisms and potential benefits for in vivo RNA visualisation are discussed. 相似文献
77.
Rotor‐stator‐machinery is characterized in continuous operation by a homogeneous power input and a defined residence time. The influence of the equipment configuration and process design in the laminar flow regime was considered little till now. In order to fill this knowledge gap, the process behavior of this type of device was systematically investigated experimentally under axial flow conditions, as well as an energetic optimization of the machine configuration was performed. 相似文献
78.
Dr. Li Di Prof. Per Artursson Dr. Alex Avdeef Prof. Leslie Z. Benet Prof. J. Brian Houston Dr. Manfred Kansy Edward H. Kerns Prof. Hans Lennernäs Dr. Dennis A. Smith Prof. Kiyohiko Sugano 《ChemMedChem》2020,15(20):1862-1874
Passive permeability is a key property in drug disposition and delivery. It is critical for gastrointestinal absorption, brain penetration, renal reabsorption, defining clearance mechanisms and drug-drug interactions. Passive diffusion rate is translatable across tissues and animal species, while the extent of absorption is dependent on drug properties, as well as in vivo physiology/pathophysiology. Design principles have been developed to guide medicinal chemistry to enhance absorption, which combine the balance of aqueous solubility, permeability and the sometimes unfavorable compound characteristic demanded by the target. Permeability assays have been implemented that enable rapid development of structure-permeability relationships for absorption improvement. Future advances in assay development to reduce nonspecific binding and improve mass balance will enable more accurately measurement of passive permeability. Design principles that integrate potency, selectivity, passive permeability and other ADMET properties facilitate rapid advancement of successful drug candidates to patients. 相似文献
79.
Polyethylene terephthalate (PET) is one of the most common thermoplastic polymers and its durability has become a major environmental concern. The current public debate on plastic debris also triggered the revision of PET recycling technologies. This Research Article focuses on the chemical recycling of PET by means of methanolysis. The process degrades PET into two main reaction products, dimethyl terephthalate (DMT) and ethylene glycol (EG). Subsequent separation by distillation combined with crystallization removes critical impurities and non-PET components from co-polymers, providing monomers of high purity needed for re-polymerization purposes. 相似文献
80.
Salahaldeen Dababat Dr. Ghizlane Enaime Prof. Dr. Ing. Marc Wichern Dr. Ing. Manfred Lübken 《化学,工程师,技术》2023,95(12):1881-1896
Aerobic granular sludge (AGS) technology is gaining increasing interest globally. However, several aspects are still challenging its installation, as the integration into existing municipal wastewater treatment plants. The operation of AGS units in continuous flow mode could facilitate that integration; yet has only been experienced at lab and pilot scales. Further, handling of excess granular sludge constitutes a prominent challenge. Even that, adopting effective strategies for its management holds promising contributions to the circular economy by fostering the reuse and recovery of valuable resources. The recovery of phosphorus and alginate-like polymers holds significant commercial potential worldwide, with broad applications in agriculture, food, pharmaceuticals, and biotechnology. 相似文献