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401.
Differential intestinal anti‐inflammatory effects of Lactobacillus fermentum and Lactobacillus salivarius in DSS mouse colitis: impact on microRNAs expression and microbiota composition
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402.
Song J Webb A Parmenter B Allen DT McDonald-Buller E 《Environmental science & technology》2008,42(19):7294-7300
The impacts of alternative regional development patterns on emissions, dry deposition, and air quality were examined using four visions of future land use in Austin, Texas associated with a doubling of the population in 20-40 years from 2001. Emissions and their spatial allocation were determined based on the development pattern and used to predict hourly ozone concentrations. Differences in hourly ozone concentrations due to changes in anthropogenic emissions between the future case scenarios and a 2007 base case ranged from -14 to 22 ppb and were primarily associated with the implementation of federal mobile source standards; differences due to biogenic emissions and dry deposition due to urbanization ranged from only -1.4 to 0.7 ppb. These differences in the magnitude of emissions produced greater changes in air quality than differences in regional development patterns between the four scenarios. Differences in hourly ozone concentrations between the future development scenarios and a 2007 base case ranged from -14 to 22 ppb, in contrast to differences of -3 to 5 ppb between the future scenarios. The results imply that although the effects of urbanization patterns are non-negligible, the pattern of urban development is not as significant as reductions in emissions per capita. 相似文献
403.
Joan Farré Pons Alba Alumá Felipe Antoja Carmen Biosca María-Jesús Alsina Román Galimany 《Journal of Automated Methods and Management in Chemistry》1990,12(4):153-162
The selective multitest Coulter Dacos 3.0 analyser was evaluated according to the guidelines of the Comisión de Instrumentación de la Sociedad Española de Química Clínica and of the European Committee for Clinical Laboratory Standards.The evaluation was performed in four steps: examination of the analytical units; evaluation of routine working; study of interferences; and assessment of practicability.The evaluation included a photometric study. The inaccuracy is acceptable for 340 nm and 420 nm, and the imprecision at absorbances from 0.05 to 2.00 ranged from 0.06 to 0.28% at 340 nm and from 0.06 to 0.08% at 420 nm. The linearity showed some dispersion at low absorbance for PNP at 420 nm and the drift was negligible.The imprecision of the pipette delivery system, the temperature control system and the washing system were satisfactory.In routine work conditions, seven analytical methods were studied: glucose, creatinine, iron, total protein, AST, ALP and calcium. Within-run imprecision ranged, at low concentrations, from 0.9% (CV) for glucose, to 7.6% (CV) for iron; at medium concentrations, from 0.7% (CV) for total protein to 5.2% (CV) to creatinine; and at high concentrations, it ranged from 0.6% (CV) for glucose to 3.9% (CV) for ALP.Between-run imprecision at low concentrations ranged from 1.4% (CV) for glucose to 15.1% (CV) for iron; at medium concentrations it ranged from 1.2% (CV) for protein to 6.7% (CV) for iron; and at high concentrations the range is from l.2for AST to 5.7% (CV) for iron.No contamination was found in the sample carry-over study. Some contamination was found in the reagent carry-over study (total protein due to iron and calcium reagents). Relative inaccuracy is good for all the constituents assayed. Only LDH (high and low levels) and urate (low level) showed weak and negative interference caused by turbidity, and γ-GT (high level) and amylase, bilirubin and ALP (two levels) showed a negative interference caused by haemolysis. 相似文献
404.
405.
Justin C Sanchez Nicolas Alba Toshikazu Nishida Christopher Batich Paul R Carney 《IEEE transactions on neural systems and rehabilitation engineering》2006,14(2):217-221
Long-term viability of chronic invasive neural probes is a necessary condition for extracting robust control signals directly from neural tissue. Although immune/tissue response is a leading factor in the degradation of single neuron recording, we investigate a second component of signal degradation connected to the structural changes associated with microwire electrodes chronically exposed to extracelluar environments in vivo. Scanning electron microscopy is used to assess the surface modifications to the electrodes after an implantation duration of four weeks in rats. The electrode developed a smooth fracture surface, a reduction of the metal diameter, and pitting in the insulation of the electrode structure. Over the duration of implantation, recording properties of the electrode were marked by a reduction in the peak-to-peak amplitude in neuronal firing. 相似文献
406.
Alba Giacalone Antonio Gianguzza Maria Rosaria Mannino Santino Orecchio Daniela Piazzese 《Polycyclic Aromatic Compounds》2013,33(2):135-149
The content of 21 polycyclic aromatic hydrocarbons (PAHs) were determined in 16 samples of sediments collected from Ganzirri and Faro marine coastal lagoons in Messina, Italy. Analysis was performed by gas chromatography/mass spectrometry (GC/MS) in selected ion monitoring (SIM) mode. The total concentration of polycyclic aromatic hydrocarbons (ΣPAHs) ranged from 74 to 5755 μg/kg of dry matrix. The resulting distributions and molecular ratios of specific compounds are discussed in terms of sampling location and origin of organic matter. The results obtained show that levels of contamination are not homogeneous throughout the stations, while the relative distributions of PAHs are homogeneous in most of the sampling stations. The organic matter content and PAH concentration were found to be correlated (r = 0.90). It is also shown that the pyrolytic origin is the main source of these compounds in Ganzirri and Faro Lakes sediments. 相似文献
407.
Antoni Parcerisas Alba Ortega-Gasc Marc Hernaiz-Llorens Maria Antonia Odena Fausto Ulloa Eliandre de Oliveira Miquel Bosch Lluís Pujadas Eduardo Soriano 《International journal of molecular sciences》2021,22(14)
Neuronal cell adhesion molecule 2 (NCAM2) is a membrane protein with an important role in the morphological development of neurons. In the cortex and the hippocampus, NCAM2 is essential for proper neuronal differentiation, dendritic and axonal outgrowth and synapse formation. However, little is known about NCAM2 functional mechanisms and its interactive partners during brain development. Here we used mass spectrometry to study the molecular interactome of NCAM2 in the second postnatal week of the mouse cerebral cortex. We found that NCAM2 interacts with >100 proteins involved in numerous processes, including neuronal morphogenesis and synaptogenesis. We validated the most relevant interactors, including Neurofilaments (NEFs), Microtubule-associated protein 2 (MAP2), Calcium/calmodulin kinase II alpha (CaMKIIα), Actin and Nogo. An in silico analysis of the cytosolic tail of the NCAM2.1 isoform revealed specific phosphorylation site motifs with a putative affinity for some of these interactors. Our results expand the knowledge of NCAM2 interactome and confirm the key role of NCAM2 in cytoskeleton organization, neuronal morphogenesis and synaptogenesis. These findings are of interest in explaining the phenotypes observed in different pathologies with alterations in the NCAM2 gene. 相似文献
408.
Inflammation, oxidative stress, and obesity 总被引:1,自引:0,他引:1
Fernández-Sánchez A Madrigal-Santillán E Bautista M Esquivel-Soto J Morales-González A Esquivel-Chirino C Durante-Montiel I Sánchez-Rivera G Valadez-Vega C Morales-González JA 《International journal of molecular sciences》2011,12(5):3117-3132
Obesity is a chronic disease of multifactorial origin and can be defined as an increase in the accumulation of body fat. Adipose tissue is not only a triglyceride storage organ, but studies have shown the role of white adipose tissue as a producer of certain bioactive substances called adipokines. Among adipokines, we find some inflammatory functions, such as Interleukin-6 (IL-6); other adipokines entail the functions of regulating food intake, therefore exerting a direct effect on weight control. This is the case of leptin, which acts on the limbic system by stimulating dopamine uptake, creating a feeling of fullness. However, these adipokines induce the production of reactive oxygen species (ROS), generating a process known as oxidative stress (OS). Because adipose tissue is the organ that secretes adipokines and these in turn generate ROS, adipose tissue is considered an independent factor for the generation of systemic OS. There are several mechanisms by which obesity produces OS. The first of these is the mitochondrial and peroxisomal oxidation of fatty acids, which can produce ROS in oxidation reactions, while another mechanism is over-consumption of oxygen, which generates free radicals in the mitochondrial respiratory chain that is found coupled with oxidative phosphorylation in mitochondria. Lipid-rich diets are also capable of generating ROS because they can alter oxygen metabolism. Upon the increase of adipose tissue, the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), was found to be significantly diminished. Finally, high ROS production and the decrease in antioxidant capacity leads to various abnormalities, among which we find endothelial dysfunction, which is characterized by a reduction in the bioavailability of vasodilators, particularly nitric oxide (NO), and an increase in endothelium-derived contractile factors, favoring atherosclerotic disease. 相似文献
409.
The replication cycle of human immunodeficiency virus type 1 (HIV-1) is a complex multistep process that depends on both viral and host cell factors. The nuclear protein lens epithelium-derived growth factor (LEDGF/p75) is a multidomain protein, present in host cells, which plays an important role in the integration process. LEDGF/p75 not only binds HIV-1 integrase (IN) at its IN binding domain (IBD) but also contains several motifs that function in DNA and chromatin binding. The demonstrated importance of the association between IN and LEDGF/p75 in HIV-1 integration suggests the possibility that this protein-protein interaction (PPI) could be exploited as an antiviral target. We describe herein the progress to date in developing inhibitors of this promising target. 相似文献
410.
This work evidences the suitability of applying a single twisted nematic liquid-crystal (TN-LC) device to obtain dynamic polarimeters with high accuracy and repeatability. Different Stokes polarimeter setups based on a TN-LC device are optimized, leading to the minimization of the noise propagated from intensity measurements to the Stokes vector calculations. To this aim, we revise the influence of working out of normal incidence and of performing a double pass of the light beam through the LC device. In addition, because transmissive TN-LC devices act as elliptical retarders, an extra study is performed. It analyzes the influence of projecting the light exiting from the TN-LC device over elliptical states of polarization. Finally, diverse optimized polarimeters are experimentally implemented and validated by measuring different states of partially and fully polarized light. The analysis is conducted both for monochromatic (He-Ne laser) and LED light sources, proving the potential of polarimeters based on a single TN-LC device. 相似文献