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61.
Genome-wide association studies (GWAS) have identified many risk loci for complex diseases, but effect sizes are typically small and information on the underlying biological processes is often lacking. Associations with metabolic traits as functional intermediates can overcome these problems and potentially inform individualized therapy. Here we report a comprehensive analysis of genotype-dependent metabolic phenotypes using a GWAS with non-targeted metabolomics. We identified 37 genetic loci associated with blood metabolite concentrations, of which 25 show effect sizes that are unusually high for GWAS and account for 10-60% differences in metabolite levels per allele copy. Our associations provide new functional insights for many disease-related associations that have been reported in previous studies, including those for cardiovascular and kidney disorders, type 2 diabetes, cancer, gout, venous thromboembolism and Crohn's disease. The study advances our knowledge of the genetic basis of metabolic individuality in humans and generates many new hypotheses for biomedical and pharmaceutical research.  相似文献   
62.
63.
We studied reproduction of three species of crocodilians, Paleosuchus trigonatus, Caiman crocodilus and Melanosuchus niger, in the Xingu River, near the Belo Monte hydroelectric dam. The periods of laying and hatching of eggs were estimated for each nest before (2013–2014) and after (2016–2017) the river was dammed and the reservoir was formed. Nesting of the three species occurred between August and December, but was largely asynchronous; nest construction peaked in September for P. trigonatus, October for M. niger and November for C. crocodilus. Reservoir filling had little effect on the laying period of any of the species. Nests of P. trigonatus and M. niger were always within 0–12 m of the bank, whereas nests of C. crocodilus, which nests later in the season when flooding is more likely, were up to 100 m from the nearest water body. There was no relationship between distance from water and the number of eggs in nests, suggesting that larger and presumably more experienced females do not lay at different distances from the bank in any of the species.  相似文献   
64.
Our interest focusses on the idea, that consciousness is a powerful acting entity. Up to now there does not exist a scientific concept for this idea. This is not due to problems within the field of psychology or brain research, but rather in resisting theories of modern physics. That is, why we have to search for a solution in the field of physics. A solution can be found in a new understanding of the basics of physical theory. That could be given by abstract and absolute quantum bits of information (AQI bits). To avoid the popular misunderstanding of “information” as “meaningful” it was necessary to find a new word for the free-of-meaning AQI bits: the AQI bits establish a quantum pre-structure termed “Protyposis” (Greek: “pre-formation”), out of which real objects can be formed, starting from energetical and material elementary particles. The Protyposis AQI bits provide a pre-structure for all entities in natural sciences. They are the basic entities, whereof the physical nature of the brain, on the one hand, and the mental nature of consciousness, on the other hand, were formed during the cosmological and the following biological evolution. A deeper understanding of quantum structures may help to overcome the resistance against quantum theory in the field of brain research and consciousness. The key for an understanding is the concept of Protyposis, which means an abstract quantum information free of any definite meaning. With the AQI bits of the Protyposis, both, massless and massive quantum particles can be constructed. Even quantum information with special meanings, in example grammatically formulated thoughts, eventually could be explained. As long as the fundamental basis of quantum theory is misunderstood as being formed by a manifold of some small objects like atoms, quarks, or strings, the problem of understanding consciousness has no solution. If instead we understand quantum theory as based on truly simple quantum structures, there would be no longer fundamental problems for an understanding of consciousness.  相似文献   
65.
The Ca2+-binding protein parvalbumin (PV) and mitochondria play important roles in Ca2+ signaling, buffering and sequestration. Antagonistic regulation of PV and mitochondrial volume is observed in in vitro and in vivo model systems. Changes in mitochondrial morphology, mitochondrial volume and dynamics (fusion, fission, mitophagy) resulting from modulation of PV were investigated in MDCK epithelial cells with stable overexpression/downregulation of PV. Increased PV levels resulted in smaller, roundish cells and shorter mitochondria, the latter phenomenon related to reduced fusion rates and decreased expression of genes involved in mitochondrial fusion. PV-overexpressing cells displayed increased mitophagy, a likely cause for the decreased mitochondrial volumes and the smaller overall cell size. Cells showed lower mobility in vitro, paralleled by reduced protrusions. Constitutive PV down-regulation in PV-overexpressing cells reverted mitochondrial morphology and fractional volume to the state present in control MDCK cells, resulting from increased mitochondrial movement and augmented fusion rates. PV-modulated, bi-directional and reversible mitochondrial dynamics are key to regulation of mitochondrial volume.  相似文献   
66.
The protein kinase D (PKD) family of proteins are important regulators of tumor growth, development, and progression. CRT0066101, an inhibitor of PKD, has antitumor activity in multiple types of carcinomas. However, the effect and mechanism of CRT0066101 in bladder cancer are not understood. In the present study, we show that CRT0066101 suppressed the proliferation and migration of four bladder cancer cell lines in vitro. We also demonstrate that CRT0066101 blocked tumor growth in a mouse flank xenograft model of bladder cancer. To further assess the role of PKD in bladder carcinoma, we examined the three PKD isoforms and found that PKD2 was highly expressed in eight bladder cancer cell lines and in urothelial carcinoma tissues from the TCGA database, and that short hairpin RNA (shRNA)-mediated knockdown of PKD2 dramatically reduced bladder cancer growth and invasion in vitro and in vivo, suggesting that the effect of the compound in bladder cancer is mediated through inhibition of PKD2. This notion was corroborated by demonstrating that the levels of phospho-PKD2 were markedly decreased in CRT0066101-treated bladder tumor explants. Furthermore, our cell cycle analysis by flow cytometry revealed that CRT0066101 treatment or PKD2 silencing arrested bladder cancer cells at the G2/M phase, the arrest being accompanied by decreases in the levels of cyclin B1, CDK1 and phospho-CDK1 (Thr161) and increases in the levels of p27Kip1 and phospho-CDK1 (Thr14/Tyr15). Moreover, CRT0066101 downregulated the expression of Cdc25C, which dephosphorylates/activates CDK1, but enhanced the activity of the checkpoint kinase Chk1, which inhibits CDK1 by phosphorylating/inactivating Cdc25C. Finally, CRT0066101 was found to elevate the levels of Myt1, Wee1, phospho-Cdc25C (Ser216), Gadd45α, and 14-3-3 proteins, all of which reduce the CDK1-cyclin B1 complex activity. These novel findings suggest that CRT0066101 suppresses bladder cancer growth by inhibiting PKD2 through induction of G2/M cell cycle arrest, leading to the blockade of cell cycle progression.  相似文献   
67.
68.
A critical factor in the transmission and pathogenesis of Toxoplasma gondii is the ability to convert from an acute disease-causing, proliferative stage (tachyzoite), to a chronic, dormant stage (bradyzoite). The conversion of the tachyzoite-containing parasitophorous vacuole membrane into the less permeable bradyzoite cyst wall allows the parasite to persist for years within the host to maximize transmissibility to both primary (felids) and secondary (virtually all other warm-blooded vertebrates) hosts. This review presents our current understanding of the latent stage, including the factors that are important in bradyzoite induction and maintenance. Also discussed are the recent studies that have begun to unravel the mechanisms behind stage switching.  相似文献   
69.
Skin barrier function and allergic risk   总被引:11,自引:0,他引:11  
Hudson TJ 《Nature genetics》2006,38(4):399-400
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70.
Difficulties in fine-mapping quantitative trait loci (QTLs) are a major impediment to progress in the molecular dissection of complex traits in mice. Here we show that genome-wide high-resolution mapping of multiple phenotypes can be achieved using a stock of genetically heterogeneous mice. We developed a conservative and robust bootstrap analysis to map 843 QTLs with an average 95% confidence interval of 2.8 Mb. The QTLs contribute to variation in 97 traits, including models of human disease (asthma, type 2 diabetes mellitus, obesity and anxiety) as well as immunological, biochemical and hematological phenotypes. The genetic architecture of almost all phenotypes was complex, with many loci each contributing a small proportion to the total variance. Our data set, freely available at http://gscan.well.ox.ac.uk, provides an entry point to the functional characterization of genes involved in many complex traits.  相似文献   
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