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41.
Progressive supranuclear palsy (PSP) is a movement disorder with prominent tau neuropathology. Brain diseases with abnormal tau deposits are called tauopathies, the most common of which is Alzheimer's disease. Environmental causes of tauopathies include repetitive head trauma associated with some sports. To identify common genetic variation contributing to risk for tauopathies, we carried out a genome-wide association study of 1,114 individuals with PSP (cases) and 3,247 controls (stage 1) followed by a second stage in which we genotyped 1,051 cases and 3,560 controls for the stage 1 SNPs that yielded P ≤ 10(-3). We found significant previously unidentified signals (P < 5 × 10(-8)) associated with PSP risk at STX6, EIF2AK3 and MOBP. We confirmed two independent variants in MAPT affecting risk for PSP, one of which influences MAPT brain expression. The genes implicated encode proteins for vesicle-membrane fusion at the Golgi-endosomal interface, for the endoplasmic reticulum unfolded protein response and for a myelin structural component.  相似文献   
42.
Inflammatory bowel disease (IBD) is a common inflammatory disorder with complex etiology that involves both genetic and environmental triggers, including but not limited to defects in bacterial clearance, defective mucosal barrier and persistent dysregulation of the immune response to commensal intestinal bacteria. IBD is characterized by two distinct phenotypes: Crohn's disease (CD) and ulcerative colitis (UC). Previously reported GWA studies have identified genetic variation accounting for a small portion of the overall genetic susceptibility to CD and an even smaller contribution to UC pathogenesis. We hypothesized that stratification of IBD by age of onset might identify additional genes associated with IBD. To that end, we carried out a GWA analysis in a cohort of 1,011 individuals with pediatric-onset IBD and 4,250 matched controls. We identified and replicated significantly associated, previously unreported loci on chromosomes 20q13 (rs2315008[T] and rs4809330[A]; P = 6.30 x 10(-8) and 6.95 x 10(-8), respectively; odds ratio (OR) = 0.74 for both) and 21q22 (rs2836878[A]; P = 6.01 x 10(-8); OR = 0.73), located close to the TNFRSF6B and PSMG1 genes, respectively.  相似文献   
43.
Aspergillus fumigatus is exceptional among microorganisms in being both a primary and opportunistic pathogen as well as a major allergen. Its conidia production is prolific, and so human respiratory tract exposure is almost constant. A. fumigatus is isolated from human habitats and vegetable compost heaps. In immunocompromised individuals, the incidence of invasive infection can be as high as 50% and the mortality rate is often about 50% (ref. 2). The interaction of A. fumigatus and other airborne fungi with the immune system is increasingly linked to severe asthma and sinusitis. Although the burden of invasive disease caused by A. fumigatus is substantial, the basic biology of the organism is mostly obscure. Here we show the complete 29.4-megabase genome sequence of the clinical isolate Af293, which consists of eight chromosomes containing 9,926 predicted genes. Microarray analysis revealed temperature-dependent expression of distinct sets of genes, as well as 700 A. fumigatus genes not present or significantly diverged in the closely related sexual species Neosartorya fischeri, many of which may have roles in the pathogenicity phenotype. The Af293 genome sequence provides an unparalleled resource for the future understanding of this remarkable fungus.  相似文献   
44.
Résumé Chez les lapins gris et blancs de la Nouvelle-Zélande, la concentration d'une enzyme semblable à la rénine est 16 fois plus grande dans l'utérus gravide presque à terme que dans l'utérus non-gravide et 9.5 fois plus grande que dans l'utérus après néphrectomie bilatérale. En tenant compte du fort accroissement de l'utérus gravide, le contenu total de l'enzyme en question est 114 fois supérieur à celui de l'utérus non-gravide et 24 fois plus grand que celui du rein.  相似文献   
45.
46.
Observations of martian surface morphology have been used to argue that an ancient ocean once existed on Mars. It has been thought that significant quantities of such water could have been supplied to the martian surface through volcanic outgassing, but this suggestion is contradicted by the low magmatic water content that is generally inferred from chemical analyses of igneous martian meteorites. Here, however, we report the distributions of trace elements within pyroxenes of the Shergotty meteorite--a basalt body ejected 175 million years ago from Mars--as well as hydrous and anhydrous crystallization experiments that, together, imply that water contents of pre-eruptive magma on Mars could have been up to 1.8%. We found that in the Shergotty meteorite, the inner cores of pyroxene minerals (which formed at depth in the martian crust) are enriched in soluble trace elements when compared to the outer rims (which crystallized on or near to the martian surface). This implies that water was present in pyroxenes at depth but was largely lost as pyroxenes were carried to the surface during magma ascent. We conclude that ascending magmas possibly delivered significant quantities of water to the martian surface in recent times, reconciling geologic and petrologic constraints on the outgassing history of Mars.  相似文献   
47.
The carbon-to-oxygen ratio (C/O) in a planet provides critical information about its primordial origins and subsequent evolution. A primordial C/O greater than 0.8 causes a carbide-dominated interior, as opposed to the silicate-dominated composition found on Earth; the atmosphere can also differ from those in the Solar System. The solar C/O is 0.54 (ref. 3). Here we report an analysis of dayside multi-wavelength photometry of the transiting hot-Jupiter WASP-12b (ref. 6) that reveals C/O?≥?1 in its atmosphere. The atmosphere is abundant in CO. It is depleted in water vapour and enhanced in methane, each by more than two orders of magnitude compared to a solar-abundance chemical-equilibrium model at the expected temperatures. We also find that the extremely irradiated atmosphere (T?>?2,500?K) of WASP-12b lacks a prominent thermal inversion (or stratosphere) and has very efficient day-night energy circulation. The absence of a strong thermal inversion is in stark contrast to theoretical predictions for the most highly irradiated hot-Jupiter atmospheres.  相似文献   
48.
We measure the performance of multi‐model inference (MMI) forecasts compared to predictions made from a single model for crude oil prices. We forecast the West Texas Intermediate (WTI) crude oil spot prices using total OECD petroleum inventory levels, surplus production capacity, the Chicago Board Options Exchange Volatility Index and an implementation of a subset autoregression with exogenous variables (SARX). Coefficient and standard error estimates obtained from SARX determined by conditioning on a single ‘best model’ ignore model uncertainty and result in underestimated standard errors and overestimated coefficients. We find that the MMI forecast outperforms a single‐model forecast for both in‐ and out‐of‐sample datasets over a variety of statistical performance measures, and further find that weighting models according to the Bayesian information criterion generally yields superior results both in and out of sample when compared to the Akaike information criterion. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
49.
We recently generated an advanced mouse model of Alzheimer’s disease (AD) by targeted knock-in of single-copy mutated human amyloid precursor-protein (APP) and tau genes, crossed with a non-symptomatic presenilin (PS1A246E) over-expressing mouse line. These PLB1Triple mice presented with age-dependent and AD-relevant phenotypes. Homozygous PLB1Triple mice aged 4–12 months were assessed here in a battery of spatial learning tasks: Exp.1 radial-arm water maze (spatial reference and working memory) Exp.2 open-field water maze (spatial reference memory); Exp.3 home cage observation system with spatial learning (IntelliCage); Exp.4 spontaneous object recognition (SOR; novel object and spatial object shift). A separate test with high-expression transgenic APP mice matching the design of experiment 1 was also performed. Spatial deficits in PLB1Triple mice were confirmed at 12, but not 4 months in both water maze tasks. PSAPP mice, by contrast, presented with severe yet non-progressive spatial learning deficits already at 4 months. During tests of spatial learning in SOR and IntelliCage, PLB1Triple mice neither acquired the location of the water-rewarded corner, nor recognize novel or spatially shifted objects at 4 months, indicating these protocols to be more sensitive than the water maze. Collectively and in line with AD symptomatology, PLB1Triple mice present with a graded and progressive age-dependent loss of spatial memory that can be revealed by the use of a battery of tasks. With the emergence of subtle deficits progressively increasing in severity, PLB1Triple mice may offer a more patho-physiologically relevant model of dementia than aggressive expression models.  相似文献   
50.
F Stenb?ck  G Curtis  W Ryan 《Experientia》1979,35(9):1232-1233
Double-stranded polynucleotide polyadenylate-polyuridylate (Poly AU) enhanced skin tumor formation in Swiss mice by 75% when injected prior to a single application of 7,12-dimethylbenzanthracene (DMBA). When given after the carcinogen application Poly AU did not significantly enhance tumor formation.  相似文献   
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