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51.
Magdalena Banas Katarzyna Zabieglo Gopinath Kasetty Monika Kapinska-Mrowiecka Julia Borowczyk Justyna Drukala Krzysztof Murzyn Brian A. Zabel Eugene C. Butcher Jens M. Schroeder Artur Schmidtchen Joanna Cichy 《PloS one》2013,8(3)
Chemerin, a chemoattractant ligand for chemokine-like receptor 1 (CMKLR1) is predicted to share similar tertiary structure with antibacterial cathelicidins. Recombinant chemerin has antimicrobial activity. Here we show that endogenous chemerin is abundant in human epidermis, and that inhibition of bacteria growth by exudates from organ cultures of primary human skin keratinocytes is largely chemerin-dependent. Using a panel of overlapping chemerin-derived synthetic peptides, we demonstrate that the antibacterial activity of chemerin is primarily mediated by Val66-Pro85, which causes direct bacterial lysis. Therefore, chemerin is an antimicrobial agent in human skin. 相似文献
52.
Gemma Navarro Estefania Moreno Jordi Bonaventura Marc Brugarolas Daniel Farré David Aguinaga Josefa Mallol Antoni Cortés Vicent Casadó Carmen Lluís Sergi Ferre Rafael Franco Enric Canela Peter J. McCormick 《PloS one》2013,8(4)
Under normal conditions the brain maintains a delicate balance between inputs of reward seeking controlled by neurons containing the D1-like family of dopamine receptors and inputs of aversion coming from neurons containing the D2-like family of dopamine receptors. Cocaine is able to subvert these balanced inputs by altering the cell signaling of these two pathways such that D1 reward seeking pathway dominates. Here, we provide an explanation at the cellular and biochemical level how cocaine may achieve this. Exploring the effect of cocaine on dopamine D2 receptors function, we present evidence of σ1 receptor molecular and functional interaction with dopamine D2 receptors. Using biophysical, biochemical, and cell biology approaches, we discovered that D2 receptors (the long isoform of the D2 receptor) can complex with σ1 receptors, a result that is specific to D2 receptors, as D3 and D4 receptors did not form heteromers. We demonstrate that the σ1-D2 receptor heteromers consist of higher order oligomers, are found in mouse striatum and that cocaine, by binding to σ1 -D2 receptor heteromers, inhibits downstream signaling in both cultured cells and in mouse striatum. In contrast, in striatum from σ1 knockout animals these complexes are not found and this inhibition is not seen. Taken together, these data illuminate the mechanism by which the initial exposure to cocaine can inhibit signaling via D2 receptor containing neurons, destabilizing the delicate signaling balance influencing drug seeking that emanates from the D1 and D2 receptor containing neurons in the brain. 相似文献
53.
Aims
Body mass index (BMI) shows several limitations as indicator of fatness. Using the International Obesity Task Force (IOTF) reference and the World Health Organization (WHO) standard 2007 on the same dataset yielded widely different rates. At higher levels, BMI and the BMI cut-offs may be help in informing a clinical judgement, but at levels near the norm additional criteria may be needed. This study compares the prevalence of overweight and obesity using IOTF and WHO-2007 references and interprets body composition by comparing measures of BMI and body fatness (fat mass index, FMI; and waist-to-height ratio, WHtR) among an adolescent population.Methods and Results
A random sample (n = 1231) of adolescent population (12–17 years old) was interviewed. Weight, height, waist circumference, triceps and subscapular skinfolds were used to calculate BMI, FMI, and WHtR. The prevalence of overweight and obesity were 12.3% and 15.4% (WHO standards) and 18.6% and 6.1% (IOTF definition). Despite that IOTF cut-offs misclassified less often than WHO standards, BMI categories were combined with FMI and WHtR resulting in the Adiposity & Fat Distribution for adolescents (AFAD-A) classification, which identified the following groups normal-weight normal-fat (73.2%), normal-weight overfat (2.1%), overweight normal-fat (6.7%), overweight overfat (11.9%) and obesity (6.1%), and also classified overweight at risk and obese adolescents into type-I (9.5% and 1.3%, respectively) and type-II (2.3% and 4.9%, respectively) depending if they had or not abdominal fatness.Conclusions
There are differences between IOTF and WHO-2007 international references and there is a misclassification when adiposity is considered. The BMI limitations, especially for overweight identification, could be reduced by adding an estimate of both adiposity (FMI) and fat distribution (WHtR). The AFAD-A classification could be useful in clinical and population health to identify overfat adolescent and those who have greater risk of developing weight-related cardiovascular diseases according to the BMI category. 相似文献54.
Mercè Guàrdia Guillaume Charrier Antoni Vilanova Robert Savé Thierry Ameglio Neus Aletà 《Tree Genetics & Genomes》2016,12(5):83
The growing interest in broadleaf timber plantations in the Mediterranean area has promoted several studies focusing on the identification and characterization of variability sources in main timber-producing species. J. regia is one of these species, well-adapted to this area, but with freezing, damages registrations. Breeding focused on productive traits should include knowledge of adaptation, required to obtain a good selection capable of producing a suitable turnover in timber plantations. In this study, the features evaluated were autumn and winter frost hardiness and some vegetative traits on 22 half-sib J. regia progenies. Budsticks were exposed to sub-zero temperatures in a controlled chamber and using measurements of relative electrolyte content, the LT50 values (°C) were calculated by each individual. The study was carried out on seven-year-old progenies. The familiar heritability of autumn frost hardiness was 0.68, and on winter, it was 0.77. The autumn frost behaviour correlated genetically with the length of the growing season (0.574 ± 0.351), and both autumn and winter frost hardiness correlated inversely with secondary annual growth measured at breast height (?0.654 ± 0.259 and ?0.740 ± 0.227, respectively). These results pointed that growth could therefore be improved without increasing the frost vulnerability. This should be important for growers, particularly under climate change conditions. 相似文献
55.
HD2C histone deacetylase and a SWI/SNF chromatin remodelling complex interact and both are involved in mediating the heat stress response in Arabidopsis
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56.
57.
Traditional Mediterranean diet includes the halophyte Crithmum maritimum L. (Apiaceae) which can be found in the coastline of the Balearic Islands but also inland. Both areas differed in the environmental conditions, mainly in salinity which can affect the oxidative status of this species. The aim was to evaluate the antioxidant enzyme activities, polyphenols and the lipid peroxidation in leaves of wild C. maritimum growing in a natural coastal area influenced by marine salinity and an inland area without marine influence. The activities of the antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase as well as polyphenol and reduced glutathione content were significantly higher in the samples from coastline population, whereas no significant differences were found in glutathione reductase activity and in malondialdehyde levels. The production of H2O2 was also significantly higher in the population from coastline. In conclusion, C. maritimum adapt their antioxidant defense machinery to the different salinity conditions, avoiding the instauration of oxidative stress. 相似文献
58.
Extracellular vesicles (EVs), which include a variety of nano‐sized membrane‐encapsulated particles, are released to the extracellular microenvironment by the vast majority of cells and carry lipids, proteins, mRNA, and miRNA or non‐coding RNA. Increasing evidence suggests the great versatility and potential of EV‐based applications in humans. In this issue, van Balkom et al. explore and compare the reported proteomic signature of mesenchymal stromal cell (MSC)‐derived small EVs. In particular, their paper offers a valuable approach and point of view on MSC‐EV manufacturing and therapeutic potential. Briefly, van Balkom et al. aimed to identify a common protein signature that may be useful in ensuring the homogeneity of therapeutic MSC‐EVs. In addition to excessive variability in EV‐producing cell sources and culture conditions, the harvesting time for the EV‐containing conditioned medium, and EV isolation procedure, the authors found a specific protein signature from the publicly available MSC‐EVs proteome. In light of their findings and those from the plentiful studies published in this continuously growing area of research, potential focus areas and issues are outlined for the more rational design and optimization of MSC‐EV production and potency for therapeutics. 相似文献
59.
Justus Masa Stefan Piontek Patrick Wilde Hendrik Antoni Till Eckhard Yen‐Ting Chen Martin Muhler Ulf‐Peter Apfel Wolfgang Schuhmann 《Liver Transplantation》2019,9(26)
Breakthroughs toward effective water‐splitting electrocatalysts for mass hydrogen production will necessitate material design strategies based on unexplored material chemistries. Herein, Ni‐metalloid (B, Si, P, As, Te) alloys are reported as an emergent class of highly promising electrocatalysts for the oxygen evolution reaction (OER) and insight is offered into the origin of activity enhancement on the premise of the surface electronic structure, the OER activation energy, influence of the guest metalloid elements on the lattice structure of the host metal (Ni), and surface‐oxidized metalloid oxoanions. The metalloids modify the lattice structure of Ni, causing changes in the nearest Ni–Ni interatomic distance (dNi–Ni). The activation energy Ea scales with dNi–Ni indicating an apparent dependence of the OER activity on lattice properties. During the OER, surface Ni atoms are oxidized to nickel oxyhydroxide, which is the active state of the catalyst, meanwhile, the surface metalloids are oxidized to the corresponding oxoanions that affect the interfacial electrode/electrolyte properties and hence the adsorption/desorption interaction energies of the reacting species. 相似文献
60.
Kocharova NA Ovchinnikova OG Torzewska A Shashkov AS Knirel YA Rozalski A 《Carbohydrate research》2007,342(3-4):665-670
An oligosaccharide that corresponds to the repeating unit of the O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O36. Structural studies of the oligosaccharide and O-deacylated lipopolysaccharide were performed using sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY, and H-detected (1)H,(13)C HSQC and HMBC experiments. It was found that the O-polysaccharide is built up of linear trisaccharide repeating units containing 2-acetamido-2-deoxyglucose, 6-deoxy-l-talose (l-6dTal), and 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) and has the following structure. [structure: see text] 相似文献