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1.
Rechargeable graphite dual‐ion batteries (GDIBs) have attracted the attention of electrochemists and material scientists in recent years due to their low cost and high‐performance metrics, such as high power density (≈3–175 kW kg?1), energy efficiency (≈80–90%), long cycling life, and high energy density (up to 200 Wh kg?1), suited for grid‐level stationary storage of electricity. The key feature of GDIBs is the exploitation of the reversible oxidation of the graphite network with concomitant and highly efficient intercalation/deintercalation of bulky anionic species between graphene layers. In this review, historical and current research aspects of GDIBs are discussed, along with key challenges in their development and practical deployment. Specific emphasis is given to the operational mechanism of GDIBs and to unbiased and correct reporting of theoretical cell‐level energy densities. 相似文献
2.
Rafael Ricci-Azevedo Aline Ferreira Oliveira Marina C. A. V. Conrado Fernanda Caroline Carvalho Maria Cristina Roque-Barreira 《PLoS neglected tropical diseases》2016,10(4)
ArtinM, a D-mannose binding lectin from Artocarpus heterophyllus, has immunomodulatory activities through its interaction with N-glycans of immune cells, culminating with the establishment of T helper type 1 (Th1) immunity. This interaction protects mice against intracellular pathogens, including Leishmania major and Leishmania amazonensis. ArtinM induces neutrophils activation, which is known to account for both resistance to pathogens and host tissue injury. Although exacerbated inflammation was not observed in ArtinM-treated animals, assessment of neutrophil responses to ArtinM is required to envisage its possible application to design a novel immunomodulatory agent based on carbohydrate recognition. Herein, we focus on the mechanisms through which neutrophils contribute to ArtinM-induced protection against Leishmania, without exacerbating inflammation. For this purpose, human neutrophils treated with ArtinM and infected with Leishmania major were analyzed together with untreated and uninfected controls, based on their ability to eliminate the parasite, release cytokines, degranulate, produce reactive oxygen species (ROS), form neutrophil extracellular traps (NETs) and change life span. We demonstrate that ArtinM-stimulated neutrophils enhanced L. major clearance and at least duplicated tumor necrosis factor (TNF) and interleukin-1beta (IL-1β) release; otherwise, transforming growth factor-beta (TGF-β) production was reduced by half. Furthermore, ROS production and cell degranulation were augmented. The life span of ArtinM-stimulated neutrophils decreased and they did not form NETs when infected with L. major. We postulate that the enhanced leishmanicidal ability of ArtinM-stimulated neutrophils is due to augmented release of inflammatory cytokines, ROS production, and cell degranulation, whereas host tissue integrity is favored by their shortened life span and the absence of NET formation. Our results reinforce the idea that ArtinM may be considered an appropriate molecular template for the construction of an efficient anti-infective agent. 相似文献
3.
Lodovica Vergani Marina Fanin Andrea Martinuzzi Andrea Galassi Andrea Appi Rosalba Carrozzo Maurizio Rosa Corrado Angelini 《Molecular and cellular biochemistry》1990,98(1-2):225-230
Summary FABPs in the various tissues play an important role in the intracellular fatty acid transport and metabolism. Reye's syndrome (RS) and multisystemic lipid storage (MLS) are human disorders characterized by a disturbance of lipid metabolism of unknown etiology. We investigated for the first time L-FABP in these two conditions. Affinity purified antibodies against chicken L-FABP were raised in rabbits, and found to cross-react specifically with partially purified human L-FABP. L-FABP content in liver samples of two patients with RS and MLS was investigated by immuno-histochemistry, SDS-PAGE and ELISA. L-FABP immuno-histochemistry showed increased reactivity in the liver of RS patient and normal reactivity in MLS liver. L-FABP increase in RS liver was confirmed by densitometry of SDS-PAGE and ELISA method. By these two methods the increase amounted to 180% and 199% (p < 0.02), respectively, as compared to controls. A possible role of L-FABP in the pathogenesis of RS is discussed. 相似文献
4.
The variability of the cardiac rhythm was studied in males with different initial respiratory rates. At rest and during voluntarily controlled breathing, subjects with medium respiratory rates were found to have a less variable heart rate than their counterparts with low or high respiratory rates. 相似文献
5.
The speed and accuracy of protein synthesis are fundamental parameters for understanding the fitness of living cells, the quality control of translation, and the evolution of ribosomes. In this study, we analyse the speed and accuracy of the decoding step under conditions reproducing the high speed of translation in vivo. We show that error frequency is close to 10−3, consistent with the values measured in vivo. Selectivity is predominantly due to the differences in kcat values for cognate and near-cognate reactions, whereas the intrinsic affinity differences are not used for tRNA discrimination. Thus, the ribosome seems to be optimized towards high speed of translation at the cost of fidelity. Competition with near- and non-cognate ternary complexes reduces the rate of GTP hydrolysis in the cognate ternary complex, but does not appreciably affect the rate-limiting tRNA accommodation step. The GTP hydrolysis step is crucial for the optimization of both the speed and accuracy, which explains the necessity for the trade-off between the two fundamental parameters of translation. 相似文献
6.
G. N. Borisyuk R. M. Borisyuk A. B. Kirillov E. I. Kovalenko V. I. Kryukov 《Biological cybernetics》1985,52(5):301-306
A new method is proposed to analyse dependencies in point processes, which takes into account specific character of neuronal activity. Simulation modelling of neuronal network revealed that the estimated weight of connection depends monotonically on the value of the model synaptic strength. In contrast to the crosscorrelation, the method allows for nonlinear interconnections and does not require point processes to be stationary and samples to be large. Examples are presented of the method's application to neurophysiological data analysis. 相似文献
7.
Marina Cinco 《FEMS microbiology letters》1992,92(1):15-18
This investigation was undertaken to select antigenic variants of a Borrelia burgdorferi strain in vitro. The original strain BITS was cultivated in BSK medium supplemented with increasing concentrations of homologous hyperimmune serum raised in rabbits. After a few serial passages starting from a subinhibitory serum dilution of 1:800 in BSK up to 1:200, a variant named BITSv was obtained; it grew abundantly like the control culture in the presence of hyperimmune serum. Analysis of the antigenic pattern of the original and derived variants by Western blotting revealed that BITSv, compared to the original strain BITS, had lost the reactivity with the immune serum at the level of the oligosaccharide moiety. These experiments, designed to mimic the possible action of antibodies that arise during a Borrelia infection, suggest that lipopolysaccharides are surface located and that they play a role in the integrity of the outer membrane during the multiplication of Borrelia burgdorferi. 相似文献
8.
A B Maslennikov S P Kovalenko E A Oteva T A Filimonova N P Mertvetsov 《Genetika》1991,27(12):2152-2156
Restriction fragments' length polymorphism in the region of apolipoprotein A-I (apo A-I) gene was investigated in Novosibirsk (Siberia, USSR) population. Correlation between PstI apo A-I alleles (2,2 kb-P1; 3,3 kb-P2) and total cholesterol, triglycerides, high density polyproteins cholesterol, and apolipoprotein A-I level was analysed. A tendency to increase in cholesterol index of atherogenicity and to decrease in high density lipoproteins cholesterol as well as apolipoprotein A-I level was shown to occur for P1P2 genotype patients. 相似文献
9.
10.
Paolo d’Errico Marina Boido Antonio Piras Valeria Valsecchi Elena De Amicis Denise Locatelli Silvia Capra Francesco Vagni Alessandro Vercelli Giorgio Battaglia 《PloS one》2013,8(12)
Loss of the survival motor neuron gene (SMN1) is responsible for spinal muscular atrophy (SMA), the most common inherited cause of infant mortality. Even though the SMA phenotype is traditionally considered as related to spinal motor neuron loss, it remains debated whether the specific targeting of motor neurons could represent the best therapeutic option for the disease. We here investigated, using stereological quantification methods, the spinal cord and cerebral motor cortex of ∆7 SMA mice during development, to verify extent and selectivity of motor neuron loss. We found progressive post-natal loss of spinal motor neurons, already at pre-symptomatic stages, and a higher vulnerability of motor neurons innervating proximal and axial muscles. Larger motor neurons decreased in the course of disease, either for selective loss or specific developmental impairment. We also found a selective reduction of layer V pyramidal neurons associated with layer V gliosis in the cerebral motor cortex. Our data indicate that in the ∆7 SMA model SMN loss is critical for the spinal cord, particularly for specific motor neuron pools. Neuronal loss, however, is not selective for lower motor neurons. These data further suggest that SMA pathogenesis is likely more complex than previously anticipated. The better knowledge of SMA models might be instrumental in shaping better therapeutic options for affected patients. 相似文献