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991.
Laura Barberi Bianca Maria Scicchitano Manuela De Rossi Anne Bigot Stephanie Duguez Aurore Wielgosik Claire Stewart Jamie McPhee Maria Conte Marco Narici Claudio Franceschi Vincent Mouly Gillian Butler-Browne Antonio Musarò 《Biogerontology》2013,14(3):273-292
Although adult skeletal muscle is composed of fully differentiated fibers, it retains the capacity to regenerate in response to injury and to modify its contractile and metabolic properties in response to changing demands. The major role in the growth, remodeling and regeneration is played by satellite cells, a quiescent population of myogenic precursor cells that reside between the basal lamina and plasmalemma and that are rapidly activated in response to appropriate stimuli. However, in pathologic conditions or during aging, the complete regenerative program can be precluded by fibrotic tissue formation and resulting in functional impairment of the skeletal muscle. Our study, along with other studies, demonstrated that although the regenerative program can also be impaired by the limited proliferative capacity of satellite cells, this limit is not reached during normal aging, and it is more likely that the restricted muscle repair program in aging is presumably due to missing signals that usually render the damaged muscle a permissive environment for regenerative activity. 相似文献
992.
José Vitor Lima-Filho Liliane Vilela Martins Danielle Cristina de Oliveira Nascimento Roberta Ferreira Ventura Jacqueline Ellen Camelo Batista Ayrles Fernanda Brandão Silva Maria Taciana Ralph Renata Valença Vaz Carlos Boa-Viagem Rabello Isabella de Matos Mendes da Silva Joaquim Evêncio-Neto 《The Brazilian journal of infectious diseases》2013,17(1):54-61
The zoonotic potential to cause human and/or animal infections among multidrug-resistant extraintestinal pathogenic Escherichia coli from avian origin was investigated. Twenty-seven extraintestinal pathogenic E. coli isolates containing the increased survival gene (iss) were obtained from the livers of healthy and diseased poultry carcasses at two slaughterhouses in Salvador, northeastern Brazil. The antimicrobial resistance-susceptibility profiles were conducted with antibiotics of avian and/or human use by the standardized disc-diffusion method. Antimicrobial resistance was higher for levofloxacin (51.8%), amoxicillin/clavulanic acid (70.4%), ampicillin (81.5%), cefalotin (88.8%), tetracycline (100%) and streptomycin (100%). The minimum inhibitory concentrations above the resistance breakpoints of doxycycline, neomycin, oxytetracycline and enrofloxacin reached, respectively, 88.0%, 100%, 75% and 91.7% of the isolates. Strains with high and low antimicrobial resistance were i.p. administered to Swiss mice, and histopathological examination was carried out seven days after infection. Resistance to goat and human serum complement was also evaluated. The results show that Swiss mice challenged with strain 2B (resistant to 11 antimicrobials) provoked a severe degeneration of hepatocytes besides lymphocytic infiltration in the liver, whereas the spleen showed areas of degeneration of the white and red pulp. Conversely, the spleen and liver of mice challenged with strain 4A (resistant to two antimicrobials) were morphologically preserved. In addition, complement resistance to goat and human serum was high for strain 2B and low for strain 4A. Our data show that multidrug resistance and pathogenesis can be correlated in extraintestinal pathogenic E. coli strains obtained from apparently healthy poultry carcasses, increasing the risk for human public healthy. 相似文献
993.
994.
Maite Aznárez‐Sanado PhD Maria A. Fernández‐Seara PhD Francis R. Loayza PhD Maria A. Pastor MD PhD 《Journal of magnetic resonance imaging : JMRI》2013,37(3):619-631
Purpose:
To elucidate differences in activity and connectivity during early learning due to the performing hand.Materials and Methods:
Twenty right‐handed subjects were recruited. The neural correlates of explicit visuospatial learning executed with the right, the left hand, and bimanually were investigated using functional magnetic resonance imaging. Connectivity analyses were carried out using the psychophysiological interactions model, considering right and left anterior putamen as index regions.Results:
A common neural network was found for the three tasks during learning. Main activity increases were located in posterior cingulate cortex, supplementary motor area, parietal cortex, anterior putamen, and cerebellum (IV–V), whereas activity decrements were observed in prefrontal regions. However, the left hand task showed a greater recruitment of left hippocampal areas when compared with the other tasks. In addition, enhanced connectivity between the right anterior putamen and motor cortical and cerebellar regions was found for the left hand when compared with the right hand task.Conclusion:
An additional recruitment of brain regions and increased striato‐cortical and striato‐cerebellar functional connections is needed when early learning is performed with the nondominant hand. In addition, access to brain resources during learning may be directed by the dominant hand in the bimanual task. J. Magn. Reson. Imaging 2013;37:619–631. © 2012 Wiley Periodicals, Inc. 相似文献995.
Maria del C. Valdés Hernández PhD Rory J. Piper BMedSc Xin Wang MSc Ian J. Deary PhD Joanna M. Wardlaw MD 《Journal of magnetic resonance imaging : JMRI》2013,38(4):774-785
Enlarged perivascular spaces (EPVS), visible in brain MRI, are an important marker of small vessel disease and neuroinflammation. We systematically evaluated the literature up to June 2012 on possible methods for their computational assessment and analyzed confounds with lacunes and small white matter hyperintensities. We found six studies that assessed/identified EPVS computationally by seven different methods, and four studies that described techniques to automatically segment similar structures and are potentially suitable for EPVS segmentation. T2‐weighted MRI was the only sequence that identified all EPVS, but FLAIR and T1‐weighted images were useful in their differentiation. Inconsistency within the literature regarding their diameter and terminology, and overlap in shape, intensity, location, and size with lacunes, conspires against their differentiation and the accuracy and reproducibility of any computational segmentation technique. The most promising approach will need to combine various MR sequences and consider all these features for accurate EPVS determination. J. Magn. Reson. Imaging 2013;38:774–785. © 2013 Wiley Periodicals, Inc. 相似文献
996.
Ana Paula Rocha-de-Melo Cristovam Wanderley Picanço-Diniz Juliana Maria Carrazzone Borba Jailma Santos-Monteiro Rubem Carlos Araújo Guedes 《Nutritional neuroscience》2013,16(4):207-216
AbstractTissue distribution of nitric oxide-synthases was investigated in the rat hippocampus and visual cortex under nutritional changes induced by modification of the litter size. Young (30-45-days-old) rats, suckled in litters formed by 3, 6 or 12 pups (called small, medium and large litters, respectively), were studied by using nicotine-adenine-dinucleotide phosphate-diaphorase histochemistry (shortly, diaphorase), a simple and robust procedure to characterize tissue distribution of nitric oxide-synthases. We assessed morphometric features of the diaphorase-positive cells in visual cortex, and the neuropil histochemical activity in hippocampal CA1 and dentate gyrus using densitometry analysis. In the large-litter group, the labeled-cell density in white matter of area 17 was higher, as compared to the small-litter group. There was a clear trend, in the large-litter group, to lower values of soma area, dendritic field and branches per neuron, but the differences were not significant. Densitometry analysis of hippocampus revealed a significant increase in the relative neuropil histochemical activity of the dentate gyrus molecular layer in the larger litters, which may be associated to increased compensatory blood flow in the hippocampus. The pathophysiological mechanisms of the observed changes remain to be investigated. 相似文献
997.
998.
David E. Barroso Terezinha M.P.P. Casti?eiras Fernanda S. Freitas Jane W. Marsh Mary G. Krauland Mary M. Tulenko érica L. Fonseca Ana C.P. Vicente Maria C. Rebelo Elaine O. Cerqueira Adriano C. Xavier Ana P.C.M. Cardozo Simone E.M. da Silva Lee H. Harrison 《Emerging infectious diseases》2013,19(11):1847-1850
During 2003–2012, 8 clusters of meningococcal disease were identified in Rio de Janeiro State, Brazil, all caused by serogroup C Neisseria meningitidis. The isolates were assigned to 3 clonal complexes (cc): cc11, cc32, and cc103. These hyperinvasive disease lineages were associated with endemic disease, outbreaks, and high case-fatality rates. 相似文献
999.
Anna R. Garbuglia Paola Scognamiglio Nicola Petrosillo Claudio Maria Mastroianni Pasquale Sordillo Daniele Gentile Patrizia La Scala Enrico Girardi Maria R. Capobianchi 《Emerging infectious diseases》2013,19(1):110-114
During 2011, 5 persons in the area of Lazio, Italy were infected with a monophyletic strain of hepatitis E virus that showed high sequence homology with isolates from swine in China. Detection of this genotype in Italy parallels findings in other countries in Europe, signaling the possible spread of strains new to Western countries. 相似文献
1000.
The work presented here is with a view to improving performance of sterilization services in hospitals. We carried out a survey in a large number of health establishments in the Rhône-Alpes region in France. Based on the results of this survey and a detailed study of a specific service, we have built a generic model. The generic nature of the model relies on a common structure with a high level of detail. This model can be used to improve the performance of a specific sterilization service and/or to dimension its resources. It can also serve for quantitative comparison of performance indicators of various sterilization services. 相似文献