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991.
Dastani Z Hivert MF Timpson N Perry JR Yuan X Scott RA Henneman P Heid IM Kizer JR Lyytikäinen LP Fuchsberger C Tanaka T Morris AP Small K Isaacs A Beekman M Coassin S Lohman K Qi L Kanoni S Pankow JS Uh HW Wu Y Bidulescu A Rasmussen-Torvik LJ Greenwood CM Ladouceur M Grimsby J Manning AK Liu CT Kooner J Mooser VE Vollenweider P Kapur KA Chambers J Wareham NJ Langenberg C Frants R Willems-Vandijk K Oostra BA Willems SM Lamina C Winkler TW Psaty BM Tracy RP Brody J Chen I Viikari J Kähönen M 《PLoS genetics》2012,8(3):e1002607
Circulating levels of adiponectin, a hormone produced predominantly by adipocytes, are highly heritable and are inversely associated with type 2 diabetes mellitus (T2D) and other metabolic traits. We conducted a meta-analysis of genome-wide association studies in 39,883 individuals of European ancestry to identify genes associated with metabolic disease. We identified 8 novel loci associated with adiponectin levels and confirmed 2 previously reported loci (P = 4.5×10−8–1.2×10−43). Using a novel method to combine data across ethnicities (N = 4,232 African Americans, N = 1,776 Asians, and N = 29,347 Europeans), we identified two additional novel loci. Expression analyses of 436 human adipocyte samples revealed that mRNA levels of 18 genes at candidate regions were associated with adiponectin concentrations after accounting for multiple testing (p<3×10−4). We next developed a multi-SNP genotypic risk score to test the association of adiponectin decreasing risk alleles on metabolic traits and diseases using consortia-level meta-analytic data. This risk score was associated with increased risk of T2D (p = 4.3×10−3, n = 22,044), increased triglycerides (p = 2.6×10−14, n = 93,440), increased waist-to-hip ratio (p = 1.8×10−5, n = 77,167), increased glucose two hours post oral glucose tolerance testing (p = 4.4×10−3, n = 15,234), increased fasting insulin (p = 0.015, n = 48,238), but with lower in HDL-cholesterol concentrations (p = 4.5×10−13, n = 96,748) and decreased BMI (p = 1.4×10−4, n = 121,335). These findings identify novel genetic determinants of adiponectin levels, which, taken together, influence risk of T2D and markers of insulin resistance. 相似文献
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Titanium is known to possess excellent biocompatibility as a result of corrosion resistance, lack of allergenicity when compared with many other metals. Fluoride is well known as a specific and effective caries prophylactic agent and its systemic application has been recommended widely over recent decades. Nevertheless, high fluoride concentrations impair the corrosion resistance of titanium. The purpose of this article is to summarize the current data regarding the influence of fluoride on titanium corrosion process in the last 5?years. These data demonstrate noxious effects induced by high fluoride concentration as well as low pH in the oral cavity. Therefore, such conditions should be considered when prophylactic actions are administrated in patients containing titanium implants or other dental devices. 相似文献
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Agaricus bisporous tyrosinase was immobilized on commercial available epoxy-resin Eupergit®C250L and then coated by the Layer-by-Layer method (LbL). The two novel heterogeneous biocatalysts were characterized for their morphology, pH and storage stability, kinetic properties (Km, Vmax, Vmax/Km) and reusability. These biocatalysts were used for the efficient and selective synthesis of bioactive catechols under mild and environmental friendly experimental conditions. Ascorbic acid was added in the reaction medium to inhibit the formation of ortho-quinones, thus avoiding the known enzyme suicide inactivation process. Catechols were obtained mostly in quantitative yields and conversion of substrate. Tyrosinase immobilized on Eupergit®C250L and coated by the LbL method showed better catalytic activities, higher pH and storage stability, and reusability with respect to immobilized uncoated tyrosinase. Since chemical procedures to synthesize catechols are often expensive and with high environmental impact, the use of immobilized tyrosinase represents an efficient alternative for the preparation of this family of bioactive compounds. 相似文献
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Mierke CT 《Molecular bioSystems》2012,8(6):1639-1649
Most cancer-related deaths are caused by the ability of cancer cells to metastasize. This process includes the dissemination of cancer cells from the primary tumor side and their migration to targeted organ sites. During the migration of cancer cells through the connective tissue microenvironment, which consists of endothelial cells and extracellular matrix components, biomechanical properties are crucial for the efficiency and speed of cancer cell invasion and subsequently, metastases formation. Biomechanics can enable cancer cells to migrate through tissue, transmigrate through basement membranes as well as endothelial monolayers and form metastases in targeted organs. The current focus of cancer research still lies on the investigation of cancer cell's biochemical and molecular capabilities such as molecular genetics and gene signaling, but these approaches ignore the mechanical nature of the invasion process of cancer cells. Moreover, even the role of the endothelium during the transmigration and invasion of cells is not clear, it has been seen as a passive barrier, but this could not explain all novel findings. This review discusses how cancer cells alter the structural, biochemical and mechanical properties of the endothelium to regulate their own invasiveness through extracellular matrices and hence, through the tissue microenvironment. Finally, this review sheds light on the mechanical properties of cancer cells and the interacting endothelium and points out the importance of the mechanical properties as a critical determinant for the efficiency of cancer cell invasion and the overall progression of cancer. In conclusion, the regulation of the endothelial cell's biomechanical properties by cancer cells is a critical determinant of cancer cell invasiveness and may affect the future development of new cancer treatments. 相似文献
996.
In group-living vertebrates, reliable social allies play a decisive role in dealing with stressors. For example, support by social allies is known to dampen glucocorticoid responses. It remains unknown, however, how social embedding affects the sympatho-adrenergic axis as indicated by heart rate (HR) in non-human animals. We studied the relationships between HR, pair-bond status and distance from the pair-partner in twenty-five free-ranging greylag geese (Anser anser) in a natural social environment. In three individuals, we investigated HR responses following partner loss. Overall, we found a context- and sex-dependent difference in HR between paired and unpaired individuals, paired males having a lower HR during agonistic encounters, and unpaired females having a lower HR during resting. Also, in paired females HR increased with increasing distance from the partner. Our data suggest that HR is modulated by pair-bond status in greylag geese in a context- and sex-dependent manner, which may be representative for social vertebrates in general. Despite the low sample size, the present study indicates that proper social embedding may optimize an individual's physiological investment in the social domain. This reduces individual energy expenditure and may benefit health and reproductive success. 相似文献
997.
Claudia Knief Nathana?l Delmotte Samuel Chaffron Manuel Stark Gerd Innerebner Reiner Wassmann Christian von Mering Julia A Vorholt 《The ISME journal》2012,6(7):1378-1390
The above- and below-ground parts of rice plants create specific habitats for various microorganisms. In this study, we characterized the phyllosphere and rhizosphere microbiota of rice cultivars using a metaproteogenomic approach to get insight into the physiology of the bacteria and archaea that live in association with rice. The metaproteomic datasets gave rise to a total of about 4600 identified proteins and indicated the presence of one-carbon conversion processes in the rhizosphere as well as in the phyllosphere. Proteins involved in methanogenesis and methanotrophy were found in the rhizosphere, whereas methanol-based methylotrophy linked to the genus Methylobacterium dominated within the protein repertoire of the phyllosphere microbiota. Further, physiological traits of differential importance in phyllosphere versus rhizosphere bacteria included transport processes and stress responses, which were more conspicuous in the phyllosphere samples. In contrast, dinitrogenase reductase was exclusively identified in the rhizosphere, despite the presence of nifH genes also in diverse phyllosphere bacteria. 相似文献
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Luis Huicho J. Jaime Miranda Francisco Diez-Canseco Claudia Lema Andrés G. Lescano Mylene Lagarde Duane Blaauw 《PloS one》2012,7(12)