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921.
María Fernández-Raga Clemente Tomás Roberto Fraile 《International journal of biometeorology》2010,54(4):379-392
This study was carried out in the region of Castile and Leon, Spain, from 1980 to 1998 and analyzes the relationship between
the number of monthly deaths caused by cardiovascular, respiratory and digestive diseases and three meteorological variables:
temperature, pressure and humidity. One of the innovations in this study is the application of principal component analysis
in a way that differs from its usual application: one single series representing the whole region was constructed for each
meteorological variable from the series of eight weather stations. Annual and seasonal mortality trends were also studied.
Cardiovascular diseases are the leading cause of death in Castile and Leon. The mortality related to cardiovascular, respiratory
and digestive systems shows a statistically significant rising trend across the study period (an annual increase of 6, 16
and 4‰, respectively). The pressure at which mortality is lowest is approximately the same for all causes of death (about
915 hPa), but temperature values vary greatly (16.8–19.7°C for the mean, 10.9–18.1°C for the minimum, and 24.1–27.2°C for
the maximum temperature). The most comfortable temperatures for patients with cardiovascular diseases (16.8°C) are apparently
lower than those for patients with respiratory diseases (18.1°C), which are, in turn, lower than in the case of diseases of
the digestive system (19.7°C). Finally, the optimal humidity for patients with respiratory diseases is the lowest (24%) among
the diseases, and the highest (51%) corresponds to diseases of the digestive system, while the optimal relative humidity for
the cardiovascular system is 45%. 相似文献
922.
Marcio V. B. Dias Fanglu Huang Dimitri Y. Chirgadze Manuela Tosin Dieter Spiteller Emily F. V. Dry Peter F. Leadlay Jonathan B. Spencer Tom L. Blundell 《The Journal of biological chemistry》2010,285(29):22495-22504
The thioesterase FlK from the fluoroacetate-producing Streptomyces cattleya catalyzes the hydrolysis of fluoroacetyl-coenzyme A. This provides an effective self-defense mechanism, preventing any fluoroacetyl-coenzyme A formed from being further metabolized to 4-hydroxy-trans-aconitate, a lethal inhibitor of the tricarboxylic acid cycle. Remarkably, FlK does not accept acetyl-coenzyme A as a substrate. Crystal structure analysis shows that FlK forms a dimer, in which each subunit adopts a hot dog fold as observed for type II thioesterases. Unlike other type II thioesterases, which invariably utilize either an aspartate or a glutamate as catalytic base, we show by site-directed mutagenesis and crystallography that FlK employs a catalytic triad composed of Thr42, His76, and a water molecule, analogous to the Ser/Cys-His-acid triad of type I thioesterases. Structural comparison of FlK complexed with various substrate analogues suggests that the interaction between the fluorine of the substrate and the side chain of Arg120 located opposite to the catalytic triad is essential for correct coordination of the substrate at the active site and therefore accounts for the substrate specificity. 相似文献
923.
Patrick H.C. van Berkel Jolanda Gerritsen Edwin van Voskuilen Gerrard Perdok Tom Vink Jan G.J. van de Winkel Paul W.H.I. Parren 《Biotechnology and bioengineering》2010,105(2):350-357
Rapid production of recombinant human IgG with improved antibody dependent cell‐mediated cytotoxicity (ADCC) effector function is presented. The technique employs transient expression of IgG in suspension growing HEK‐293F cells in the presence of the glycosidase inhibitor kifunensine. The procedure takes ~7 days, provided that expression plasmids encoding the IgG of interest are available. Kifunensine inhibits the N‐linked glycosylation pathway of HEK‐293F cells in the endoplasmatic reticulum, resulting in IgG with oligomannose type glycans lacking core‐fucose. IgG1 transiently produced in kifunensine‐ treated HEK‐293F cells has improved affinity for the FcγRIIIA molecule as measured in an ELISA based assay, and almost eightfold enhanced ADCC using primary peripheral blood mononuclear effector cells. Biotechnol. Bioeng. 2010; 105: 350–357. © 2009 Wiley Periodicals, Inc. 相似文献
924.
RP-HPLC/MS-APCI analysis of odd-chain TAGs from Rhodococcus erythropolis including some regioisomers
Tomáš Řezanka Olga Schreiberová Tereza Krulikovská Jan Masák Karel Sigler 《Chemistry and physics of lipids》2010,163(4-5):373-380
We used reversed phase liquid chromatography–atmospheric pressure chemical ionization mass spectrometry (RP-HPLC/MS-APCI) for direct analysis of triacylglycerols (TAGs) from four different cultivations of Rhodococcus erythropolis CCM 2595. This technique enabled us to identify and quantify the specific molecular species of TAGs directly from lipid extracts of the bacterium, including the determination of their basic characteristics such as retention time and mass spectra. A total of 17 TAGs having at least one odd-numbered-chain FA (fatty acid) were found. This is the first time when odd-chain TAGs, predominantly with pentadecanoic, margaric, and margaroleic acids, were identified. Multiple linear regression analyses were used for predicting retention times of molecular species, predominantly of odd-chain TAGs. Cultivations on two different substrates at two different temperatures (20 and 30 °C) showed that only temperature had any effect on the content of TAGs. In cultivations with succinate as a carbon source the content of these TAGs increased by half (i.e., from 23.5 to 34.2%) when the cultivation temperature was lowered from 30 to 20 °C. The content of the PoPoMo, PoMoO and PPoMo (see Table 1) TAGs containing the odd-numbered-chain margaroleic acid rose from 0.0 to 7.1% while in cultivation on phenol as a carbon source the lowering of cultivation temperature caused an increase of these TAGs from 0.5 to 6.7%. 相似文献
925.
Smith EA Hill K Marlowe F Nolin D Wiessner P Gurven M Bowles S Mulder MB Hertz T Bell A 《Current anthropology》2010,51(1):19-34
We report quantitative estimates of intergenerational transmission and population-wide inequality for wealth measures in a set of hunter-gatherer populations. Wealth is defined broadly as factors that contribute to individual or household well-being, ranging from embodied forms such as weight and hunting success to material forms such household goods, as well as relational wealth in exchange partners. Intergenerational wealth transmission is low to moderate in these populations, but is still expected to have measurable influence on an individual's life chances. Wealth inequality (measured with Gini coefficients) is moderate for most wealth types, matching what qualitative ethnographic research has generally indicated (if not the stereotype of hunter-gatherers as extreme egalitarians). We discuss some plausible mechanisms for these patterns, and suggest ways in which future research could resolve questions about the role of wealth in hunter-gatherer social and economic life. 相似文献
926.
927.
928.
IN MEMORIAM
Nico M. van Gelder (1933–2005) 相似文献929.
Devos S Laukens K Deckers P Van Der Straeten D Beeckman T Inzé D Van Onckelen H Witters E Prinsen E 《Molecular plant-microbe interactions : MPMI》2006,19(12):1431-1443
We report on the early response of Arabidopsis thaliana to the obligate biotrophic pathogen Plasmodiophora brassicae at the hormone and proteome level. Using a CYCB1;1::GUS construct, the re-initiation of infection-related cell division is shown from 4 days after inoculation on. Sensitivity to cytokinins and auxins as well as the endogenous hormone levels are evaluated. Both an enhanced cytokinin gene response and an accumulation of isopentenyl adenine and adenosine precede this re-initiation of cell division, whereas an enhanced auxin gene response is observed from 6 days after inoculation on. The alhl mutant, impaired in the cross talk between ethylene and auxins, is resistant to P. brassicae. A differential protein analysis of infected versus noninfected roots and hypocotyls was performed using two-dimensional gel electrophoresis and quantitative image analysis, coupled to matrix-assisted laser desorption ionization time of flight-time of flight mass spectrometry-based protein identification. Of the visualized proteins, 12% show altered abundance compared with the noninfected plants, including proteins involved in metabolism, cell defense, cell differentiation, and detoxification. Combining the hormone and proteome data, we postulate that, at the very first stages of Plasmodiophora infection, plasmodial-produced cytokinins trigger a local re-initiation of cell division in the root cortex. Consequently, a de novo meristematic area is established that acts as a sink for host-derived indole-3-acetic acid, carbohydrates, nitrogen, and energy to maintain the pathogen and to trigger gall development. 相似文献
930.
Connexins and their channels in cell growth and cell death 总被引:7,自引:0,他引:7
Vinken M Vanhaecke T Papeleu P Snykers S Henkens T Rogiers V 《Cellular signalling》2006,18(5):592-600
Direct communication between cells, mediated by gap junctions, is nowadays considered as an indispensable mechanism in the maintenance of cellular homeostasis. In fact, gap junctional intercellular communication is actively involved in virtually all aspects of the cellular life cycle, ranging from cell growth to cell death. For a long time, it was believed that this was merely a result of the capacity of gap junctions to control the direct intercellular exchange of essential cellular messengers. However, recent data show that the picture is more complicated than initially thought, as structural precursors of gap junctions, connexins and gap junction hemichannels, can affect the cellular homeostatic balance independently of gap junctional intercellular communication. In this paper, we summarize the current knowledge concerning the roles of connexins and their channels in the control of cellular homeostasis, with the emphasis on cell growth and cell death. We also briefly discuss the role of gap junctional intercellular communication in carcinogenesis and the potential use of connexins as tools for cancer therapy. 相似文献