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Joo Paulo de Campos da Costa Marcelo Assis Vinícius Teodoro Andre Rodrigues Camila Cristina de Foggi Miguel Angel San-Miguel Joo Paulo Pereira do Carmo Juan Andrs Elson Longo 《RSC advances》2020,10(37):21745
This study demonstrates that the electron beam irradiation of materials, typically used in characterization measurements, could be employed for advanced fabrication, modification, and functionalization of composites. We developed irradiation equipment using an electron beam irradiation source to be applied in materials modification. Using this equipment, the formation of a thick Ag film on the Ag3PO4 semiconductor is carried out by electron beam irradiation for the first time. This is confirmed by various experimental techniques (X-ray diffraction, field-emission scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy) and ab initio molecular dynamics simulations. Our calculations demonstrate that, at the earlier stages, metallic Ag growth is initiated preferentially at the (110) surface, with the reduction of surface Ag cations forming metallic Ag clusters. As the (100) and (111) surfaces have smaller numbers of exposed Ag cations, the reductions on these surfaces are slower and are accompanied by the formation of O2 molecules.This study demonstrates that the electron beam irradiation of materials, typically used in characterization measurements, could be employed for advanced fabrication, modification, and functionalization of composites. 相似文献
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Minerva Calvillo Alfonso Diaz Daniel I. Limon Miguel Angel Mayoral María Elena Chánez-Cárdenas Edgar Zenteno Luis F. Montaño Jorge Guevara Blanca Espinosa 《Neuropeptides》2013
Two hallmarks of Alzheimer diseases are the continuous inflammatory process, and the brain deposit of Amyloid b (Aβ), a cytotoxic protein. The intracellular accumulation of Aβ25–35 fractions, in the absence of Heat Shock proteins (Hs?s), could be responsible for its cytotoxic activity. As, pro-inflammatory mediators and nitric oxide control the expression of Hs?s, our aim was to investigate the effect of Aβ25–35 on the concentration of IL-1β, TNF-α and nitrite levels, and their relation to pHSF-1, Hsp-60, -70 and -90 expressions, in the rat C6 astrocyte cells. Interleukin-specific ELISA kits, immunohistochemistry with monoclonal anti-Hsp and anti pHSF-1 antibodies, and histochemistry techniques, were used. Our results showed that Aβ25–35 treatment of C6 cells increased, significantly and consistently the concentration of IL-1β, TNF-α and nitrite 3 days after initiating treatment. The immunoreactivity of C6 cells to Hsp-70 reached its peak after 3 days of treatment followed by an abrupt decrease, as opposed to Hsp-60 and -90 expressions that showed an initial and progressive increase after 3 days of Aβ25–35 treatment. pHSF-1 was identified throughout the experimental period. Nevertheless, progressive and sustained cell death was observed during all the treatment times and it was not caspase-3 dependent. Our results suggest that Hsp-70 temporary expression serves as a trigger to inhibit casapase-3 pathway and allow the expression of Hsp-60 and -90 in C6 astrocytoma cells stimulated with Aβ25–35. 相似文献
157.
Alberto Luis Fernández Laura M. V. Manoiloff Angel A. Monti 《Neuropsychological rehabilitation》2013,23(1):96-109
The effects of long-term treatment in a demented patient were evaluated in this study. One individual diagnosed with Alzheimer's dementia (AD) was treated with neuropsychological rehabilitation techniques as well as drugs for a period of 2 years and 10 months. An A–B–A–B design was performed for the cognitive treatment. Neuropsychological treatment consisted of a combination of direct re-training and training in activities of daily living. Cognitive performance was monitored with the Mattis Dementia Rating Scale. Results showed improvement and a slower decline during the treatment phases (A) as compared to the no-treatment phases (B). The Conceptualisation and Attention subscales benefited most followed by the Memory subscale. Long-term treatment was shown to be effective in AD. Although cognitive drugs may have been beneficial neuropsychological rehabilitation played an important role in the success of this treatment, appearing as a necessary condition. 相似文献
158.
Patrycja Michalska Giammarco Tenti Michelle Satriani Angel Cores María Teresa Ramos Antonio G. García José Carlos Menéndez Rafael León 《Drug development research》2020,81(3):283-294
Two multitarget hybrids, derived from an aza-analogue of CGP37157, a mitochondrial Na+/Ca2+ exchanger antagonist, and lipoic acid were designed in order to combine in a single molecule the antioxidant and Nrf2 induction properties of lipoic acid and the neuroprotective activity of CGP37157. The hybrid derivatives showed Nrf2 induction and radical scavenging properties, leading to a good neuroprotective profile against oxidative stress, together with an interesting antineuroinflammatory activity. The results obtained show differences in activity depending on the configuration of the chiral center of LA. 相似文献
159.
Jocelyn A. Silvester Isabel Comino Lisa N. Rigaux Veronica Segura Kathy H. Green Angel Cebolla Dayna Weiten Remedios Dominguez Daniel A. Leffler Francisco Leon Charles N. Bernstein Lesley A. Graff Ciaran P. Kelly Carolina Sousa Donald R. Duerksen 《Alimentary pharmacology & therapeutics》2020,52(9):1469-1479
160.
Malpica N Santos A Zuluaga MA Ledesma MJ Pérez E García-Fernández MA Desco M 《Ultrasound in medicine & biology》2004,30(3):303-309
Analysis of intramyocardial perfusion by contrast echocardiography provides quantitative parameters for the assessment of ischemic disease. This analysis can be achieved by applying an ultrasound (US) burst of high mechanical index to destroy contrast bubbles, measuring various myocardial refilling parameters from the time curves obtained from regions-of-interest (ROIs) within the myocardial wall. To obtain reliable intensity curves, the position of the ROIs must be tracked to compensate for the heart motion along the sequence. In this work, we studied the use of optical flow techniques for ROI repositioning. Two block-matching and one differential technique were evaluated for this purpose. Performance was measured by comparing the result of automatic tracking with results of ROI repositioning by a human expert. This evaluation was carried out on experimental data from animals as well as on sequences from clinical studies. Results are considered to be accurate enough for clinical purposes, and computation times may allow for a real-time processing if incorporated into a US scanner. 相似文献