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151.
Sebastián Moran Miguel Vizoso Anna Martinez-Cardús Antonio Gomez Xavier Matías-Guiu Sebastián M Chiavenna Andrés G Fernandez Manel Esteller 《Epigenetics》2014,9(6):829-833
A formalin-fixed paraffin-embedded (FFPE) sample usually yields highly degraded DNA, which limits the use of techniques requiring high-quality DNA, such as Infinium Methylation microarrays. To overcome this restriction, we have applied an FFPE restoration procedure consisting of DNA repair and ligation processes in a set of paired fresh-frozen (FF) and FFPE samples. We validated the FFPE results in comparison with matched FF samples, enabling us to use FFPE samples on the Infinium HumanMethylation450 Methylation array. 相似文献
152.
Helena Lindström Johan Luthman Peter Mouton Peter Spencer† Lars Olson 《Journal of neurochemistry》1990,55(3):941-949
In the present study the subacute effects of beta-N-oxalylamino-L-alanine (BOAA) and beta-N-methylamino-L-alanine (BMAA) on CNS monoamine neurons in rats were investigated following intracisternal injections or local intracerebral administration into substantia nigra. In vitro effects of BOAA and BMAA on high-affinity synaptosomal uptake of dopamine (DA), noradrenaline (NA), and serotonin (5-HT) were also examined. Intracisternal administration of BMAA decreased NA levels in hypothalamus, whereas no effects were seen on DA or 5-HT levels. Following intranigral injections of BOAA, NA levels tended to decrease in several regions, whereas the DA levels and the levels of DA metabolites were unaffected in all regions analyzed. Loss of tyrosine hydroxylase (TH) immunoreactivity in the intranigral injection sites and the presence of TH-immunoreactive pyknotic neurons near the borders of the injection sites were observed following both BOAA and BMAA treatments. Furthermore, substance P-immunoreactive terminals in substantia nigra pars reticulata were also found to have disappeared within the lesioned area following either BOAA or BMAA injections. Incubations with both BOAA and BMAA (10(-5) M) reduced high-affinity [3H]NA uptake in cortical synaptosomes to 69% and 41% of controls, respectively, whereas the striatal high-affinity [3H]DA uptake and the cortical high-affinity [3H]5-HT uptake were unaffected by BOAA or BMAA. The results demonstrate that both BOAA and BMAA can affect central monoamine neurons, although the potency and specificity of these substances on monoamine neurons when administered acutely into cerebral tissue or liquor cerebri seem to be low. However, the in vitro studies indicate selective effects of both compounds on NA neurons in synaptosomal preparations. 相似文献
153.
David Ambrosek Pierre-François Loos Xavier Assfeld 《Journal of inorganic biochemistry》2010,104(9):893-214
The structural and spectroscopic properties of [Ru(phen)2(dppz)]2+ and [Ru(tap)2(dppz)]2+ (phen = 1,10-phenanthroline; tap = 1,4,5,8-tetraazaphenanthrene; dppz = dipyridophenazine ) have been investigated by means of density functional theory (DFT), time-dependent DFT (TD-DFT) within the polarized continuum model (IEF-PCM) and quantum mechanics/molecular mechanics (QM/MM) calculations. The model of the Δ and Λ enantiomers of Ru(II) intercalated in DNA in the minor and major grooves is limited to the metal complexes intercalated in two guanine-cytosine base pairs. The main experimental spectral features of these complexes reported in DNA or synthetic polynucleotides are better reproduced by the theoretical absorption spectra of the Δ enantiomers regardless of intercalation mode (major or minor groove). This is especially true for [Ru(phen)2(dppz)]2+. The visible absorption of [Ru(tap)2(dppz)]2+ is governed by the MLCTtap transitions regardless of the environment (water, acetonitrile or bases pair), the visible absorption of [Ru(phen)2(dppz)]2+ is characterized by transitions to metal-to-ligand-charge-transfer MLCTdppz in water and acetonitrile and to MLCTphen when intercalated in DNA. The response of the ILdppz state to the environment is very sensitive. In vacuum, water and acetonitrile these transitions are characterized by significant oscillator strengths and their positions depend significantly on the medium with blue shifts of about 80 nm when going from vacuum to solvent. When the complex is intercalated in the guanine-cytosine base pairs the 1ILdppz transition contributes mainly to the band at 370 nm observed in the spectrum of [Ru(phen)2(dppz)]2+ and to the band at 362 nm observed in the spectrum of [Ru(tap)2(dppz)]2+. 相似文献
154.
Wen‐Yuan Lin F. Xavier Pi‐Sunyer Chiu‐Shong Liu Tsai‐Chung Li Chia‐Ing Li Chih‐Yang Huang Cheng‐Chieh Lin 《Obesity (Silver Spring, Md.)》2009,17(6):1247-1254
Betel nut chewing has been reported to increase the risk of cardiovascular disease and all‐cause mortality. The reason is unclear. In this study, we investigated the association between betel nut chewing and general obesity (BMI ≥25 kg/m2) and central obesity (waist circumference (WC) ≥90 cm). A total of 1,049 male subjects, aged ≥40 years, were recruited from Taichung city in Taiwan in 2004. The relationships between betel nut chewing and general and central obesity were studied by multiple linear and logistic regression analyses. The prevalence of current and former betel nut chewing was 7.0 and 10.5% in our male Taiwanese cohort. Current/former betel nut chewers had a higher prevalence of general and central obesity when compared with individuals who had never chewed betel nut. Adjusted for age, diabetes, hypertension, lipids, smoking, alcohol drinking, physical activity, income, and education level, the odds ratios (ORs; 95% confidence intervals) of general and central obesity among the lower consumption of betel nut chewers were 1.78 (1.07, 2.96) and 1.19 (0.70, 2.02), respectively, compared to 2.01 (1.18, 3.41) and 1.89 (1.10, 3.23), respectively, among higher consumption chewers compared to individuals who had never chewed betel nut. The increasing ORs of general and central obesity with higher betel nut consumption revealed dose–response effects. Using multiple linear regression analyses, after adjusting for potential confounders, betel nut consumption was statistically significantly associated with BMI and WC. In conclusion, betel nut chewing was independently associated with general and central obesity in Taiwanese men. Dose–response effects of the association between betel nut consumption and general obesity as well as central obesity were found. 相似文献
155.
Pascale?May-PanloupEmail author Xavier?Vignon Marie-Fran?oise?Chrétien Yvan?Heyman Manoel?Tamassia Yves?Malthièry Pascal?Reynier 《Reproductive biology and endocrinology : RB&E》2005,3(1):65
Background
Recent work has shown that mitochondrial biogenesis and mitochondrial functions are critical determinants of embryonic development. However, the expression of the factors controlling mitochondrial biogenesis in early embryogenesis has received little attention so far. 相似文献156.
Invertebrates living in sulfide-rich environments have developed different strategies of coping with sulfide toxicity. Some bivalves and annelids have hemoglobins that are capable of binding sulfide for detoxification and/or transporting it to internal bacterial symbionts. Annelids living in the sulfide-rich environments have giant (approximately 3.6 MDa) hemoglobin, consisting of 144 globin chains arranged in a hexagonal bilayer structure held together by 36 nonglobin linker chains. Some globin chains contain either a free cysteine residue at positions Cys+1 or at position Cys+11 relative to the E7 distal residue in the E helix and EF interhelical region, respectively, which bind sulfide. The hexagonal bilayer hemoglobins of annelids living in environments lacking sulfide, do not have the corresponding free cysteine residues and cannot bind sulphide. Given that the early stages of life occurred under anoxic conditions in the presence of sulfide, it is possible that the sulfide binding function from modern annelid globins inhabiting sulphide rich habitats is an evolutionary relic. This proposal seems supported by the recent finding of "protoglobins" which also have a corresponding cysteine residue in Archea known to exist in hyperthermophilic and sulfide-rich environments. 相似文献
157.
Johan Van de Koppel Richard D. Bardgett Janne Bengtsson Claudino Rodriguez-Barrueco Max Rietkerk Martin J. Wassen Volkmar Wolters 《Ecosystems》2005,8(7):801-807
Food chain models have dominated empirical studies of trophic interactions in the past decades, and have lead to important
insights into the factors that control ecological communities. Despite the importance of food chain models in instigating
ecological investigations, many empirical studies still show a strong deviation from the dynamics that food chain models predict.
We present a theoretical framework that explains some of the discrepancies by showing that trophic interactions are likely
to be strongly influenced by the spatial configuration of consumers and their resources. Differences in the spatial scale
at which consumers and their resources function lead to uncoupling of the population dynamics of the interacting species,
and may explain overexploitation and depletion of resource populations. We discuss how changed land use, likely the most prominent
future stress on natural systems, may affect food web dynamics by interfering with the scale of interaction between consumers
and their resource. 相似文献
158.
Frédérick R Charlier C Robert S Wouters J Masereel B Pochet L 《Bioorganic & medicinal chemistry letters》2006,16(7):2017-2021
The synthesis of novel coumarins bearing on the lateral side chain in the 3-position an amine or a guanidine group is described. In vitro evaluation highlighted 14d which possesses a meta aniline side chain as a very potent THR inhibitor. Surprisingly, the introduction of a guanidine moiety always led to a decrease in THR inhibiting properties. We, thus, used docking experiments to rationalize the SAR in the series. This study showed the crucial role of a conserved water molecule in the specificity pocket of THR during docking simulation in order to explain the inactivity of guanidine derivatives. 相似文献
159.
Johanna Blomqvist Thomas Eberhard Johan Schnürer Volkmar Passoth 《Applied microbiology and biotechnology》2010,87(4):1487-1497
The influence of pH, temperature and carbon source (glucose and maltose) on growth rate and ethanol yield of Dekkera bruxellensis was investigated using a full-factorial design. Growth rate and ethanol yield were lower on maltose than on glucose. In controlled
oxygen-limited batch cultivations, the ethanol yield of the different combinations varied from 0.42 to 0.45 g (g glucose)−1 and growth rates varied from 0.037 to 0.050 h−1. The effect of temperature on growth rate and ethanol yield was negligible. It was not possible to model neither growth rate
nor ethanol yield from the full-factorial design, as only marginal differences were observed in the conditions tested. When
comparing three D. bruxellensis strains and two industrial isolates of Saccharomyces cerevisiae, S. cerevisiae grew five times faster, but the ethanol yields were 0–13% lower. The glycerol yields of S. cerevisiae strains were up to six-fold higher compared to D. bruxellensis, and the biomass yields reached only 72–84% of D. bruxellensis. Our results demonstrate that D. bruxellensis is robust to large changes in pH and temperature and may have a more energy-efficient metabolism under oxygen limitation
than S. cerevisiae. 相似文献
160.
Hannah M��ller David Schmidt Sandra Steinbrink Ekaterina Mirgorodskaya Verena Lehmann Karin Habermann Felix Dreher Niklas Gustavsson Thomas Kessler Hans Lehrach Ralf Herwig Johan Gobom Aspasia Ploubidou Michael Boutros Bodo M H Lange 《The EMBO journal》2010,29(19):3344-3357
Regulation of centrosome structure, duplication and segregation is integrated into cellular pathways that control cell cycle progression and growth. As part of these pathways, numerous proteins with well‐established non‐centrosomal localization and function associate with the centrosome to fulfill regulatory functions. In turn, classical centrosomal components take up functional and structural roles as part of other cellular organelles and compartments. Thus, although a comprehensive inventory of centrosome components is missing, emerging evidence indicates that its molecular composition reflects the complexity of its functions. We analysed the Drosophila embryonic centrosomal proteome using immunoisolation in combination with mass spectrometry. The 251 identified components were functionally characterized by RNA interference. Among those, a core group of 11 proteins was critical for centrosome structure maintenance. Depletion of any of these proteins in Drosophila SL2 cells resulted in centrosome disintegration, revealing a molecular dependency of centrosome structure on components of the protein translation machinery, actin‐ and RNA‐binding proteins. In total, we assigned novel centrosome‐related functions to 24 proteins and confirmed 13 of these in human cells. 相似文献