CD46 in meningococcal disease     

Johansson L  Rytkonen A  Bergman P  Albiger B  Källström H  Hökfelt T  Agerberth B  Cattaneo R  Jonsson AB 《Science (New York, N.Y.)》2003,301(5631):373-375

The human-specific bacterial pathogen Neisseria meningitidis is a major cause of sepsis and/or meningitis. The pili of N. meningitidis interact with CD46, a human cell-surface protein involved in regulation of complement activation. Transgenic mice expressing human CD46 were susceptible to meningococcal disease, because bacteria crossed the blood-brain barrier in these mice. Development of disease was more efficient with piliated bacteria after intranasal, but not intraperitoneal, challenge of CD46 transgenic mice, suggesting that human CD46 facilitates pilus-dependent interactions at the epithelial mucosa. Hence, the human CD46 transgenic mice model is a potentially useful tool for studying pathogenesis and for vaccine development against meningococcal disease.  相似文献   

Carcinogenicity of phenacetin     

Johansson S  Angervall L 《Science (New York, N.Y.)》1979,204(4389):130

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Ecology. A bid to save the 'Galápagos of the Indian Ocean'     

Sohlman E 《Science (New York, N.Y.)》2004,303(5665):1753

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Plant circadian clocks increase photosynthesis, growth, survival, and competitive advantage   总被引：3，自引：0，他引：3  

Dodd AN  Salathia N  Hall A  Kévei E  Tóth R  Nagy F  Hibberd JM  Millar AJ  Webb AA 《Science (New York, N.Y.)》2005,309(5734):630-633

Circadian clocks are believed to confer an advantage to plants, but the nature of that advantage has been unknown. We show that a substantial photosynthetic advantage is conferred by correct matching of the circadian clock period with that of the external light-dark cycle. In wild type and in long- and short-circadian period mutants of Arabidopsis thaliana, plants with a clock period matched to the environment contain more chlorophyll, fix more carbon, grow faster, and survive better than plants with circadian periods differing from their environment. This explains why plants gain advantage from circadian control.  相似文献   

Buddenbrockia is a cnidarian worm     

Jiménez-Guri E  Philippe H  Okamura B  Holland PW 《Science (New York, N.Y.)》2007,317(5834):116-118

A major evolutionary divide occurs in the animal kingdom between the so-called radially symmetric animals, which includes the cnidarians, and the bilaterally symmetric animals, which includes all worm phyla. Buddenbrockia plumatellae is an active, muscular, parasitic worm that belongs to the phylum Myxozoa, a group of morphologically simplified microscopic endoparasites that has proved difficult to place phylogenetically. Phylogenetic analyses of multiple protein-coding genes demonstrate that Buddenbrockia is a cnidarian. This active muscular worm increases the known diversity in cnidarian body plans and demonstrates that a muscular, wormlike form can evolve in the absence of overt bilateral symmetry.  相似文献   

Cancer. Aneuploidy advantages?     

Hernando E 《Science (New York, N.Y.)》2008,322(5902):692-693

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Preindustrial to modern interdecadal variability in coral reef pH   总被引：1，自引：0，他引：1  

Pelejero C  Calvo E  McCulloch MT  Marshall JF  Gagan MK  Lough JM  Opdyke BN 《Science (New York, N.Y.)》2005,309(5744):2204-2207

The oceans are becoming more acidic due to absorption of anthropogenic carbon dioxide from the atmosphere. The impact of ocean acidification on marine ecosystems is unclear, but it will likely depend on species adaptability and the rate of change of seawater pH relative to its natural variability. To constrain the natural variability in reef-water pH, we measured boron isotopic compositions in a approximately 300-year-old massive Porites coral from the southwestern Pacific. Large variations in pH are found over approximately 50-year cycles that covary with the Interdecadal Pacific Oscillation of ocean-atmosphere anomalies, suggesting that natural pH cycles can modulate the impact of ocean acidification on coral reef ecosystems.  相似文献   

Control of stress-dependent cardiac growth and gene expression by a microRNA   总被引：2，自引：0，他引：2  

van Rooij E  Sutherland LB  Qi X  Richardson JA  Hill J  Olson EN 《Science (New York, N.Y.)》2007,316(5824):575-579

The heart responds to diverse forms of stress by hypertrophic growth accompanied by fibrosis and eventual diminution of contractility, which results from down-regulation of alpha-myosin heavy chain (alphaMHC) and up-regulation of betaMHC, the primary contractile proteins of the heart. We found that a cardiac-specific microRNA (miR-208) encoded by an intron of the alphaMHC gene is required for cardiomyocyte hypertrophy, fibrosis, and expression of betaMHC in response to stress and hypothyroidism. Thus, the alphaMHC gene, in addition to encoding a major cardiac contractile protein, regulates cardiac growth and gene expression in response to stress and hormonal signaling through miR-208.  相似文献   

Analytical and sensorial characterization of the aroma of wines produced with sour rotten grapes using GC-O and GC-MS: identification of key aroma compounds     

Barata A  Campo E  Malfeito-Ferreira M  Loureiro V  Cacho J  Ferreira V 《Journal of agricultural and food chemistry》2011,59(6):2543-2553

In the present work, the aroma profiles of wines elaborated from sound and sour rot-infected grapes as raw material have been studied by sensory analysis, gas chromatography-olfactometry (GC-O), and gas chromatography-mass spectrometry (GC-MS), with the aim of determining the odor volatiles most likely associated with this disease. The effect of sour rot was tested in monovarietal wines produced with the Portuguese red grape variety Trincadeira and in blends of Cabernet Sauvignon and sour rotten Trincadeira grapes. Wines produced from damaged berries exhibited clear honey-like notes not evoked by healthy samples. Ethyl phenylacetate (EPhA) and phenylacetic acid (PAA), both exhibiting sweet honey-like aromas, emerged as key aroma compounds of sour rotten wines. Their levels were 1 order of magnitude above those found in controls and reached 304 and 1668 μg L(-1) of EPhA and PAA, respectively, well above the corresponding odor thresholds. Levels of γ-nonalactone also increased by a factor 3 in sour rot samples. Results also suggest that sour rot exerts a great effect on the secondary metabolism of yeast, decreasing the levels of volatiles related to fatty acids and amino acid synthesis. The highest levels of γ-decalactone of up to 405 μg L(-1) were also found in all of the samples, suggesting that this could be a relevant aroma compound in Trincadeira wine aroma.  相似文献   

The effects of chronic intermittent noise exposure on broiler chicken performance     

Eva VOSLAROVA  Petr CHLOUPEK  Jan CHLOUPEK  Iveta BEDANOVA  Vladimira PISTEKOVA  Vladimir VECEREK 《Animal Science Journal》2011,82(4):601-606

Effects of different noise levels (70 or 80 dB) that broilers were exposed to during the entire fattening period and also the effect of the timing of the first exposure to intermittent noise in the course of fattening (day 1 vs. day 7) were monitored. After 7 days of exposure to intermittent noise, experimental chickens already showed a significant decrease in live body weight in comparison with the control group. The difference between the group exposed to intermittent noise at 70 dB and the group exposed to 80 dB levels was not statistically significant, although the mean live body weight of broilers in the latter was lower during the entire fattening period. The chickens exposed to intermittent noise from day 1 of age showed lower mean live weight throughout the fattening period compared to chickens exposed to the same level of intermittent noise only from day 7 of age, although at the end of fattening the difference was statistically significant only in chickens exposed to the higher level of intermittent noise (80 dB).  相似文献