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991.
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Nacira Darghal Nadia Bouchemal Carlos F.G.C. Geraldes Milena Salerno 《Journal of inorganic biochemistry》2010,104(1):47-54
Alzheimer’s disease (AD) is the most commonly form of dementia in the elderly. The development of molecules able to detect biomarkers characteristic of AD is critical to its understanding and treatment. However, such molecules must be able to pass blood-brain barrier (BBB) which is a major impediment to the entry of many therapeutic drugs into the brain. Such a limitation applies to the development of magnetic resonance imaging molecular neuroimaging agents using biomarkers of AD-like β-amyloid deposits, as the common extracellular contrast agents (CAs) are not able to cross an intact BBB. In this work, we have studied the ability of a series of simple Eu3+ complexes to enter cells overexpressing or not the ABCB1 (P-gp or P-glycoprotein) protein, which is expressed at the BBB and in human embryonic astrocytes. The intracellular uptake of the Eu3+ complexes of linear and macrocyclic polyaminocarboxylate ligands with different charges and lipophilicities was followed by atomic absorption spectrometry. Based on biochemical argument, we propose that lipophilic contrast agents can be efficiently taken up by cells and accumulate inside mitochondria when they are positively charged. The important point is that they are not P-gp substrates, which is one of the major obstacles for them to cross the BBB. 相似文献
994.
995.
Carlos Nores Fernando Ballesteros Juan C. Blanco Alicia García-Serrano Juan Herrero Guillermo Palomero 《Acta theriologica》2010,55(3):203-209
Evidence of non-hibernation in brown bears Ursus arctos Linnaeus, 1758 on the Iberian Peninsula has existed since the Middle
Ages. We systematically monitored brown bears in the Cantabrian Mountains (Northern Spain) by recording tracks and sightings
from 1998 to 2007 to document hibernation behaviour. Our results indicate that females with yearlings and solitary yearlings
were more active in winter than bears over two years old. Intensive snow tracking and direct observations of five family groups
indicated that they travelled, fed and defecated in winter, which are activities not compatible with the physiological state
of hibernation. Also, based on tracking data, the maximum period between two consecutive locations of active family groups
in winter was less than that needed by bears to emerge from a state of hibernation (6 days). We conclude that the family groups
which we monitored in winter did not hibernate. 相似文献
996.
Tompson SW Bacino CA Safina NP Bober MB Proud VK Funari T Wangler MF Nevarez L Ala-Kokko L Wilcox WR Eyre DR Krakow D Cohn DH 《American journal of human genetics》2010,87(5):708-712
Fibrochondrogenesis is a severe, autosomal-recessive, short-limbed skeletal dysplasia. In a single case of fibrochondrogenesis, whole-genome SNP genotyping identified unknown ancestral consanguinity by detecting three autozygous regions. Because of the predominantly skeletal nature of the phenotype, the 389 genes localized to the autozygous intervals were prioritized for mutation analysis by correlation of their expression with known cartilage-selective genes via the UCLA Gene Expression Tool, UGET. The gene encoding the α1 chain of type XI collagen (COL11A1) was the only cartilage-selective gene among the three candidate intervals. Sequence analysis of COL11A1 in two genetically independent fibrochondrogenesis cases demonstrated that each was a compound heterozygote for a loss-of-function mutation on one allele and a mutation predicting substitution for a conserved triple-helical glycine residue on the other. The parents who were carriers of missense mutations had myopia. Early-onset hearing loss was noted in both parents who carried a loss-of-function allele, suggesting COL11A1 as a locus for mild, dominantly inherited hearing loss. These findings identify COL11A1 as a locus for fibrochondrogenesis and indicate that there might be phenotypic manifestations among carriers. 相似文献
997.
Hiroshi Nishiura Gerardo Chowell Muntaser Safan Carlos Castillo-Chavez 《Theoretical biology & medical modelling》2010,7(1):1
Background
In many parts of the world, the exponential growth rate of infections during the initial epidemic phase has been used to make statistical inferences on the reproduction number, R, a summary measure of the transmission potential for the novel influenza A (H1N1) 2009. The growth rate at the initial stage of the epidemic in Japan led to estimates for R in the range 2.0 to 2.6, capturing the intensity of the initial outbreak among school-age children in May 2009. 相似文献998.
999.
Carlos Cepeda Damian M Cummings Véronique M André Sandra M Holley Michael S Levine 《ASN neuro》2010,2(2)
The discovery of the HD (Huntington’s disease) gene in 1993 led to the creation of genetic mouse models of the disease and opened the doors for mechanistic studies. In particular, the early changes and progression of the disease could be followed and examined systematically. The present review focuses on the contribution of these genetic mouse models to the understanding of functional changes in neurons as the HD phenotype progresses, and concentrates on two brain areas: the striatum, the site of most conspicuous pathology in HD, and the cortex, a site that is becoming increasingly important in understanding the widespread behavioural abnormalities. Mounting evidence points to synaptic abnormalities in communication between the cortex and striatum and cell–cell interactions as major determinants of HD symptoms, even in the absence of severe neuronal degeneration and death. 相似文献
1000.
Mariana Conte Silvia de Simone Susan J Simmons Carlos L Ballaré Ann E Stapleton 《BMC plant biology》2010,10(1):112