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991.
Experiments were conducted on normal level gait to determine the synergistic patterns present in the forces causing joint moments and those associated with the generation, absorption and transfer of mechanical energy. The following generalizations can be made about the patterns: (i) During swing phase three forces (gravitational, muscle and knee joint acceleration) are responsible for shank rotation, and are shown to act together during both acceleration and deceleration.—(ii) The patterns of generation, absorption and transfer of mechanical energy at the joints are detailed. These patterns demonstrate inter-segment transfers of energy through the joint centres, and through the muscles, as well as the more recognized generation and absorption by the muscles themselves.—As a result of the complexity shown in these patterns it is cautioned that fundamental relationships that may have been derived from controlled biomechanical experiments (such as horizontal flexion and extension of the forearm) are not likely to apply to more normal movements such as gait. 相似文献
992.
993.
Sucrose phosphorylase is an interesting biocatalyst that can glycosylate a variety of small molecules using sucrose as a cheap but efficient donor substrate. The low thermostability of the enzyme, however, limits its industrial applications, as these are preferably performed at 60°C to avoid microbial contamination. Cross-linked enzyme aggregates (CLEAs) of the sucrose phosphorylase from Bifidobacterium adolescentis were found to have a temperature optimum that is 17°C higher than that of the soluble enzyme. Furthermore, the immobilized enzyme displays an exceptional thermostability, retaining all of its activity after 1 week incubation at 60°C. Recycling of the biocatalyst allows its use in at least ten consecutive reactions, which should dramatically increase the commercial potential of its glycosylating activity. 相似文献
994.
Alejandra Ramirez-Martinez Nathalie Wesolek Jean-Claude Yadan Marc Moutet Alain-Claude Roudot 《人类与生态风险评估》2016,22(3):667-677
L-ergothioneine is an amino acid synthetized by fungi and mycobacteria that cannot be synthesized by other species. It has been detected in plants, animals, and the human body. In the last few years, it has been recognized as a good antioxidant and, recently, it has also been related to other properties besides antioxidant properties. Even though few studies on the toxicity of L-ergothioneine have been carried out, evidence suggests that L-ergothioneine is not harmful to health. Considering that L-ergothioneine has increasingly been linked to positive effects on human health, coupled with the fact that it seems to be safe for human consumption, this molecule may be suitable for use as an ingredient in foods. On the other hand, despite the positive effects reported for this molecule, no estimate of L-ergothioneine intake has been carried out until now. Thus, the aim of this work is to estimate the intake of L-ergothioneine through food consumption of several European countries and the United States. Values were estimated by using the deterministic and probabilistic approach. Results show that the populations with the highest intake of L-ergothioneine correspond to Italian population, both for children and adults. 相似文献
995.
996.
Valérie Guillet Ségolène Galandrin Laurent Maveyraud Simon Ladevèze Vincent Mariaule Cécile Bon Nathalie Eynard Mamadou Daffé Hedia Marrakchi Lionel Mourey 《The Journal of biological chemistry》2016,291(15):7973-7989
Mycolic acids are essential components of the mycobacterial cell envelope, and their biosynthetic pathway is one of the targets of first-line antituberculous drugs. This pathway contains a number of potential targets, including some that have been identified only recently and have yet to be explored. One such target, FadD32, is required for activation of the long meromycolic chain and is essential for mycobacterial growth. We report here an in-depth biochemical, biophysical, and structural characterization of four FadD32 orthologs, including the very homologous enzymes from Mycobacterium tuberculosis and Mycobacterium marinum. Determination of the structures of two complexes with alkyl adenylate inhibitors has provided direct information, with unprecedented detail, about the active site of the enzyme and the associated hydrophobic tunnel, shedding new light on structure-function relationships and inhibition mechanisms by alkyl adenylates and diarylated coumarins. This work should pave the way for the rational design of inhibitors of FadD32, a highly promising drug target. 相似文献
997.
Raffaele Teperino Sabine Amann Martina Bayer Sean L. McGeeAndrea Loipetzberger Timothy ConnorCarsten Jaeger Bernd KammererLilli Winter Gerhard WicheKevin Dalgaard Madhan SelvarajMichael Gaster Robert S. Lee-YoungMark A. Febbraio Claude KnaufPatrice D. Cani Fritz AbergerJosef M. Penninger J. Andrew Pospisilik Harald Esterbauer 《Cell》2012,151(2):414-426
998.
999.
Daniel Bertin Jean-Charles Grimaud Nathalie Lesavre Chahine Benelmouloud Ariadne Desjeux Stéphane Garcia Sophie Desplat-Jégo 《PloS one》2013,8(11)
Antibodies against Saccharomyces cerevisiae (ASCA) and Escherichia coli outer membrane porin C (anti-OmpC) are known to be detectable in the serum of patients with Crohn’s disease (CD) but display a very poor sensitivity for the disease especially in forms with isolated colonic involvement. In this study we aimed at evaluating performances of these markers in supernatant of cultured colonic biopsies.Patients with colonic CD (n = 67), ulcerative colitis (UC) (n = 35) and control individuals (n = 37) were prospectively recruited for colonoscopy pinch biopsies and blood sampling. Serum and supernatant of culture tissues were analyzed for ASCA and anti-OmpC. Direct immunofluorescence was also performed on colonic tissues for total IgA detection.We detected for the first time ASCA IgA/IgG and anti-OmpC IgA in cultured colonic tissue supernatants. For both markers, sensitivities for diagnosing CD were better in supernatants (ASCA: 53.7%, anti-OmpC: 28.4%) than in serum (ASCA: 31.3%, anti-OmpC: 22.4%). Combination of results from a panel of these tests gave the greatest sensitivity ever described for CD diagnosis in colonic forms (70.2%).In this study, we described, for the first time, ASCA in supernatant of colonic tissue cultures. This assaying approach in CD diagnosis should be taken into consideration in the future especially in CD forms with isolated colonic involvement. 相似文献
1000.
Valérie Collot Jana Sopkova-de Oliveira Santos Pascale Schumann-Bard Nathalie Colloc'h Eric T. MacKenzie 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):195-199
The synthesis, pharmacological evaluation and modelisation of 7-methoxyindazole (7-MI) and related alkoxy-indazoles as novel inhibitors of neuronal nitric oxide synthase are presented. 7-MI remains the most active compound of this series in an in vitro enzymatic assay of neuronal nitric oxide synthase activity. Modeling studies of the interaction of 7-substituted indazole derivatives complexed with nNOS and the relationship with their respective biological activities suggest that a bulky substitution on position-7 is responsible for a steric hindrance effect which does not allow these compounds to interact with nNOS in the same way as 7-NI and 7-MI. 相似文献