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排序方式: 共有1044条查询结果,搜索用时 15 毫秒
1.
Jorge Pascual-Fernndez Alejandro Fernndez-Montero Alfredo Crdova-Martínez Diego Pastor Alejandro Martínez-Rodríguez Enrique Roche 《International journal of molecular sciences》2020,21(22)
Aging is associated with sarcopenia. The loss of strength results in decreased muscle mass and motor function. This process accelerates the progressive muscle deterioration observed in older adults, favoring the presence of debilitating pathologies. In addition, sarcopenia leads to a decrease in quality of life, significantly affecting self-sufficiency. Altogether, these results in an increase in economic resources from the National Health Systems devoted to mitigating this problem in the elderly, particularly in developed countries. Different etiological determinants are involved in the progression of the disease, including: neurological factors, endocrine alterations, as well as nutritional and lifestyle changes related to the adoption of more sedentary habits. Molecular and cellular mechanisms have not been clearly characterized, resulting in the absence of an effective treatment for sarcopenia. Nevertheless, physical activity seems to be the sole strategy to delay sarcopenia and its symptoms. The present review intends to bring together the data explaining how physical activity modulates at a molecular and cellular level all factors that predispose or favor the progression of this deteriorating pathology. 相似文献
2.
Alfredo M. Gravagnuolo Eden Morales‐Narváez Charlene Regina Santos Matos Sara Longobardi Paola Giardina Arben Merkoçi 《Advanced functional materials》2015,25(38):6084-6092
Class I hydrophobin Vmh2, a peculiar surface active and versatile fungal protein, is known to self‐assemble into chemically stable amphiphilic films, to be able to change wettability of surfaces, and to strongly adsorb other proteins. Herein, a fast, highly homogeneous and efficient glass functionalization by spontaneous self‐assembling of Vmh2 at liquid–solid interfaces is achieved (in 2 min). The Vmh2‐coated glass slides are proven to immobilize not only proteins but also nanomaterials such as graphene oxide (GO) and quantum dots (QDs). As models, bovine serum albumin labeled with Alexa 555 fluorophore, anti‐immunoglobulin G antibodies, and cadmium telluride QDs are patterned in a microarray fashion in order to demonstrate functionality, reproducibility, and versatility of the proposed substrate. Additionally, a GO layer is effectively and homogeneously self‐assembled onto the studied functionalized surface. This approach offers a quick and simple alternative to immobilize nanomaterials and proteins, which is appealing for new bioanalytical and nanobioenabled applications. 相似文献
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Gennaro Lettieri Rosaria Notariale Alessia Ambrosino Alfredo Di Bonito Antonella Giarra Marco Trifuoggi Caterina Manna Marina Piscopo 《International journal of molecular sciences》2021,22(4)
Mercury (Hg) is an environmental pollutant that impacts human and ecosystem health. In our previous works, we reported alterations in the properties of Mytilus galloprovincialis protamine-like (PL) proteins after 24 h of exposure to subtoxic doses of toxic metals such as copper and cadmium. The present work aims to assess the effects of 24 h of exposure to 1, 10, and 100 pM HgCl2 on spermatozoa and PL proteins of Mytilus galloprovincialis. Inductively coupled plasma–mass spectrometry indicated accumulation of this metal in the gonads of exposed mussels. Further, RT-qPCR analyses showed altered expression levels of spermatozoa mt10 and hsp70 genes. In Mytilus galloprovincialis, PL proteins represent the major basic component of sperm chromatin. These proteins, following exposure of mussels to HgCl2, appeared, by SDS-PAGE, partly as aggregates and showed a decreased DNA-binding capacity that rendered them unable to prevent DNA damage, in the presence of CuCl2 and H2O2. These results demonstrate that even these doses of HgCl2 exposure could affect the properties of PL proteins and result in adverse effects on the reproductive system of this organism. These analyses could be useful in developing rapid and efficient chromatin-based genotoxicity assays for pollution biomonitoring programs. 相似文献
7.
Esther Hontañón Marcel Rouenhoff Alfredo Azabal Emilio Ramiro Frank Einar Kruis 《Aerosol science and technology》2014,48(3):333-339
An existing differential mobility analyzer (DMA) of cylindrical electrodes and a novel DMA of rectangular plate electrodes are demonstrated for size fractionation of nanoparticles at high-aerosol flow rates in this work. The two DMAs are capable of delivering monodisperse size selected nanoparticles (SMPS σg < 1.1) at gas flow rates ranging from 200 slm to 500 slm. At an aerosol flow rate of 200 slm, the maximum attainable particle mean size is of about 20 nm for the cylindrical DMA and of nearly 50 nm for the rectangular plate DMA. The number concentration of the monodisperse nanoparticles delivered by the high-flow DMAs spans from 104 cm?3 to 106 cm?3 depending upon the particle mean size and particle size dispersion.
Copyright 2014 American Association for Aerosol Research 相似文献
8.
Improved Bioactivity of Antimicrobial Peptides by Addition of Amino‐Terminal Copper and Nickel (ATCUN) Binding Motifs 下载免费PDF全文
M. Daben Libardo Dr. Jorge L. Cervantes Prof. Juan C. Salazar Prof. Alfredo M. Angeles‐Boza 《ChemMedChem》2014,9(8):1892-1901
Antimicrobial peptides (AMPs) are promising candidates to help circumvent antibiotic resistance, which is an increasing clinical problem. Amino‐terminal copper and nickel (ATCUN) binding motifs are known to actively form reactive oxygen species (ROS) upon metal binding. The combination of these two peptidic constructs could lead to a novel class of dual‐acting antimicrobial agents. To test this hypothesis, a set of ATCUN binding motifs were screened for their ability to induce ROS formation, and the most potent were then used to modify AMPs with different modes of action. ATCUN binding motif‐containing derivatives of anoplin (GLLKRIKTLL‐NH2), pro‐apoptotic peptide (PAP; KLAKLAKKLAKLAK‐NH2), and sh‐buforin (RAGLQFPVGRVHRLLRK‐NH2) were synthesized and found to be more active than the parent AMPs against a panel of clinically relevant bacteria. The lower minimum inhibitory concentration (MIC) values for the ATCUN–anoplin peptides are attributed to the higher pore‐forming activity along with their ability to cause ROS‐induced membrane damage. The addition of the ATCUN motifs to PAP also increases its ability to disrupt membranes. DNA damage is the major contributor to the activity of the ATCUN–sh‐buforin peptides. Our findings indicate that the addition of ATCUN motifs to AMPs is a simple strategy that leads to AMPs with higher antibacterial activity and possibly to more potent, usable antibacterial agents. 相似文献
9.
The objective of this paper is to investigate the regional incidence of the effects of public investment in transportation infrastructures in Portugal. Our methodological approach consists of estimating vector autoregressive (VAR) models for the national economy as well as for each of the five administrative regions in the country. In the regional models, both public investment in transportation infrastructures in the region and public investment in transportation infrastructures elsewhere are considered, thereby taking into consideration the potential existence of regional spillovers. Empirical results suggest that although public investment in transportation infrastructures has been a powerful instrument to promote long-term growth, it does so in a way that is rather unbalanced across regions. We show that public investment in transportation infrastructures has markedly contributed to the concentration of economic activity in Lisbon, the largest region in the country, and therefore has contributed markedly to the macrocephaly of the country.
相似文献
Jorge M. AndrazEmail: |
10.
Local soil amplification is one of the main phenomena contributing to local seismic hazard and consequently to local seismic risk. It is influenced both by randomness and by fuzziness. This paper offers a general fuzzy—random formulation, applicable to nonlinear soil amplification studies and hence to evaluations of local seismic hazard. The results obtainable by probabilistic analysis and also those arrived at using fuzzy analysis can be considered as consequences of particularizations of this formulation.
The treatment is rendered explicit by adapting the response surface technique to the problem, as this is advantageous in terms of computational economy. 相似文献