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Giovanni Zuliani Michela Perrone Donnorso Cristina Bosi Angelina Passaro Edoardo Dalla Nora Amedeo Zurlo Francesco Bonetti Alessia F Mozzi Claudio Cortese 《BMC neurology》2011,11(1):121
Background
In central nervous system cholesterol cannot be degraded but is secreted into circulation predominantly in the form of its polar metabolite 24(S)-hydroxycholesterol (24S-OH-Chol). Some studies suggested an association between 24S-OH-Chol metabolism and different neurological diseases including dementia. A possible decrease in 24S-OH-Chol plasma levels has been reported late onset Alzheimer's disease (LOAD) and vascular dementia (VD), but results of previous studies are partially contradictory. 相似文献414.
Lee AN Hartono YD Sun T Leow ML Liu XW Huang X Zhang D 《Journal of molecular modeling》2011,17(7):1635-1641
Molecular dynamics (MD) simulations were carried out to study the behavior of human receptor molecule in the hemagglutinin
(HA) of 1918 and 2009 H1N1 influenza viruses respectively. The 2009 HA model was obtained by virtually mutating the 1918 HA
crystal structure based on A/Mexico City/MCIG01/2009(H1N1) segment 4 sequence. We found that human receptor molecule has no
binding preference between the 2009 HA and the 1918 HA. In addition, among the four sugar moieties in the human receptor molecule,
sialic acid contributes the most to the electrostatic and non-polar interaction energy during binding. Furthermore, the hydrogen
bonds between sialic acid and the surrounding residues in 1918 HA are preserved in 2009 HA. We also found that the mutated
residues contribute to a more favorable binding of hemagglutinin to the human receptor molecule. 相似文献
415.
Angelina Mageni Lutambi Melissa A. Penny Thomas Smith Nakul Chitnis 《Mathematical biosciences》2013,241(2):198-216
Mosquito dispersal is a key behavioural factor that affects the persistence and resurgence of several vector-borne diseases. Spatial heterogeneity of mosquito resources, such as hosts and breeding sites, affects mosquito dispersal behaviour and consequently affects mosquito population structures, human exposure to vectors, and the ability to control disease transmission. In this paper, we develop and simulate a discrete-space continuous-time mathematical model to investigate the impact of dispersal and heterogeneous distribution of resources on the distribution and dynamics of mosquito populations. We build an ordinary differential equation model of the mosquito life cycle and replicate it across a hexagonal grid (multi-patch system) that represents two-dimensional space. We use the model to estimate mosquito dispersal distances and to evaluate the effect of spatial repellents as a vector control strategy. We find evidence of association between heterogeneity, dispersal, spatial distribution of resources, and mosquito population dynamics. Random distribution of repellents reduces the distance moved by mosquitoes, offering a promising strategy for disease control. 相似文献
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Paola Ringhieri Alessandra Pannunzio Angelina Boccarelli Giancarlo Morelli Mauro Coluccia 《Journal of liposome research》2016,26(4):307-312
Gynecological tumors are major therapeutic areas of platinum-based anticancer drugs. Here, we report the characterization and in vitro biological assays of cisplatin-containing Egg L-α-phosphatidylcholine liposomes with different amounts of cholesterol. Dynamic light scattering estimated sizes of all obtained liposomes in the 100?nm range that are suitable for in vivo use. On the basis of these data and of the drug loading values, the best formulation has been selected. Stability and drug release properties of platinum-containing liposomes have been verified in serum. The growth inhibitory effects of both liposomal and free drug in a panel of ovarian and breast human cancer cell lines, characterized by a different drug sensitivity, give comparable or better results with respect to free cisplatin drug. 相似文献
419.
Dario Copetti Jianwei Zhang Moaine El Baidouri Dongying Gao Jun Wang Elena Barghini Rosa M. Cossu Angelina Angelova Carlos E. Maldonado L. Stefan Roffler Hajime Ohyanagi Thomas Wicker Chuanzhu Fan Andrea Zuccolo Mingsheng Chen Antonio Costa de Oliveira Bin Han Robert Henry Yue-ie Hsing Nori Kurata Wen Wang Scott A. Jackson Olivier Panaud Rod A. Wing 《BMC genomics》2015,16(1)
Background
Comparative evolutionary analysis of whole genomes requires not only accurate annotation of gene space, but also proper annotation of the repetitive fraction which is often the largest component of most if not all genomes larger than 50 kb in size.Results
Here we present the Rice TE database (RiTE-db) - a genus-wide collection of transposable elements and repeated sequences across 11 diploid species of the genus Oryza and the closely-related out-group Leersia perrieri. The database consists of more than 170,000 entries divided into three main types: (i) a classified and curated set of publicly-available repeated sequences, (ii) a set of consensus assemblies of highly-repetitive sequences obtained from genome sequencing surveys of 12 species; and (iii) a set of full-length TEs, identified and extracted from 12 whole genome assemblies.Conclusions
This is the first report of a repeat dataset that spans the majority of repeat variability within an entire genus, and one that includes complete elements as well as unassembled repeats. The database allows sequence browsing, downloading, and similarity searches. Because of the strategy adopted, the RiTE-db opens a new path to unprecedented direct comparative studies that span the entire nuclear repeat content of 15 million years of Oryza diversity.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1762-3) contains supplementary material, which is available to authorized users. 相似文献420.
Delbin MA Moraes C Camargo E Mussi RK Antunes E de Nucci G Zanesco A 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,147(3):793-798
The aim of this work was to evaluate the effect of physical preconditioning in the responsiveness of rat pulmonary rings submitted to lung ischemia/reperfusion (IR). Wistar rats were divided into three groups: Sedentary sham-operated (SD/SHAM); sedentary submitted to ischemia/reperfusion (SD/IR) and trained submitted to ischemia/reperfusion (TR/IR) animals. Exercise training consisted in sessions of 60 min/day running sessions, 5 days/week for 8 weeks. Left pulmonary IR was performed by occluding for 90 min and reperfusing for 120 min. After that, pulmonary arteries were isolated and concentration-response curves to acetylcholine (ACh), histamine (HIST), sodium nitroprusside (SNP), phenylephrine and U46619 were obtained. Neither potency (-log EC(50)) nor maximal responses (E(max)) were modified for ACh and HIST in all groups. On the other hand, the potency for SNP was significantly increased in TR/IR group (8.23+/-0.06) compared to SD/IR group (7.85+/-0.04). Contractile responses mediated by a-adrenergic receptor were markedly decreased in IR groups (SD/IR: 6.75+/-0.06 and TR/IR: 6.62+/-0.04) compared to SD/SHAM (7.33+/-0.05). No changes were seen for the U46619 in all groups. In conclusion, the present study shows that exercise training has no protective actions in the local blood vessel where the IR process takes place. 相似文献