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1.
Sci Total Environ ; 890: 164318, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37230338

RESUMO

Plastic microfibers (MF) represent the major source of MF found in the environment, the majority made of polyester (PES). Marine bivalves, suspension feeders widespread in coastal areas subjected to higher anthropogenic input, can accumulate MF from the water column in their tissues. This raised some concern about their possible impact on bivalve health and potential transfer along the food chain. In this work, the effects of PES-MF on the mussel Mytilus galloprovincialis were investigated, utilizing MF obtained by cryo-milling of a fleece cover. Fiber characterization indicated the polymer composition as polyethylene terephthalate (PET); the size distribution was in a length range resembling that of MF released from textile washing, and including those that can be ingested by mussels. MF were first screened for short-term in vitro immune responses in mussel hemocytes. The effects of in vivo exposure (96 h, 10 and 100 µg/L, corresponding to about 150 and 1500 MF/mussel/L, respectively), were then evaluated. Data are presented on hemolymph immune biomarkers (Reactive Oxygen Species and nitric oxide production, lysozyme activity), and on antioxidant biomarkers (catalase and glutathione S-transferase) and histopathology in gills and digestive gland. Tissue MF accumulation was also evaluated. MF exposure stimulated extracellular immune responses both in vitro and in vivo, indicating induction of immune/inflammatory processes. In both tissues, stimulation of antioxidant enzyme activities, suggesting oxidative stress conditions, and histopathological changes were observed, with stronger effects often observed at lower concentration. Although mussel retained a very small fraction of MF, their accumulation was higher in the digestive gland than in gills, and in both tissues of mussels exposed to the lowest concentration. Selective accumulation of shorter MF was also observed, particularly in gills. Overall, the results demonstrate that at environmental exposure levels, PET-MF have a significant impact on mussel physiology, affecting multiple processes in different tissues.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Antioxidantes/análise , Plásticos/toxicidade , Plásticos/análise , Espécies Reativas de Oxigênio/análise , Biomarcadores/análise , Poluentes Químicos da Água/análise , Brânquias/química
2.
J Phys Condens Matter ; 29(46): 465901, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29064822

RESUMO

Quantum EXPRESSO is an integrated suite of open-source computer codes for quantum simulations of materials using state-of-the-art electronic-structure techniques, based on density-functional theory, density-functional perturbation theory, and many-body perturbation theory, within the plane-wave pseudopotential and projector-augmented-wave approaches. Quantum EXPRESSO owes its popularity to the wide variety of properties and processes it allows to simulate, to its performance on an increasingly broad array of hardware architectures, and to a community of researchers that rely on its capabilities as a core open-source development platform to implement their ideas. In this paper we describe recent extensions and improvements, covering new methodologies and property calculators, improved parallelization, code modularization, and extended interoperability both within the distribution and with external software.

3.
J Musculoskelet Neuronal Interact ; 14(1): 131-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24583548

RESUMO

Tendinopathies are a major cause of disability in the athletic population; the main purpose of the treatment of these injuries is to reduce pain and improve function. The aim of this study was to evaluate the effect of NSAIDs on leg stiffness of patients suffering acute unilateral Achilles tendinopathy. Twenty-eight eligible male athletes (aged 39.1 ± 10.3 y) suffering acute Achilles tendinopathy were treated with etoricoxib (120 mg oral once daily) during 7 days. Pain (100-mm visual analogue scale-VAS), analgesic effect (percentage of 100-mm VAS reduction), and leg stiffness were evaluated pre- and post- anti-inflammatory treatment. Results of this study showed that over the 7-day treatment period, etoricoxib provided significant relief of Achilles tendon pain (VAS) compared to that experienced at baseline: 54.5 ± 21.6 and 24.5 ± 24.8, respectively (p<0.001). Leg stiffness showed a significant improvement after one-week NSAID therapy: LSR 0.89 ± 0.1 vs. 0.97 ± 0.1; (p=0.02). In conclusion, findings of this study demonstrated that patients suffering acute unilateral Achilles tendinopathy increased their leg stiffness of the affected side after oral anti-inflammatory therapy. Effective control of tendon pain in the acute phase of such sports-related injuries may contribute to improve capabilities associated with high performance like leg stiffness.


Assuntos
Tendão do Calcâneo , Anti-Inflamatórios não Esteroides/uso terapêutico , Dor/tratamento farmacológico , Piridinas/uso terapêutico , Sulfonas/uso terapêutico , Tendinopatia/tratamento farmacológico , Tendão do Calcâneo/efeitos dos fármacos , Adulto , Atletas , Traumatismos em Atletas/complicações , Traumatismos em Atletas/tratamento farmacológico , Etoricoxib , Humanos , Perna (Membro) , Masculino , Dor/etiologia , Medição da Dor , Recuperação de Função Fisiológica/efeitos dos fármacos , Tendinopatia/complicações
4.
Phys Rev Lett ; 101(26): 266103, 2008 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-19113778

RESUMO

We show by vibrational and photoemission spectroscopy and by ab initio calculations that in ultrahigh vacuum oxygen adsorption at stepped Ag surfaces causes the formation of surface oxide phases with different stoichiometry, depending on the morphology of the steps involved in the nucleation process. On Ag(511), characterized by close-packed steps and (100) terraces, subsurface O occupies tetrahedral interstitials and an Ag2O-like phase forms; on Ag(210), showing open step edges, subsurface oxygen ends up off center in octahedral sites and an AgO-like structure nucleates.

5.
J Mol Graph Model ; 17(3-4): 176-9, 215-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10736774

RESUMO

XCrySDen is a molecular and crystalline-structure visualization program, but its main function is as a property analyzer program. It can run on most UNIX platforms, without any special hardware or software requirements. Special efforts were made to allow for appropriate display of 3D isosurfaces and 2D contours, which can be superimposed on crystalline structure and interactively rotated and manipulated. XCrySDen is also a graphical user interface for the CRYSTAL95/98 (Saunders, V. R., et al. CRYSTAL98--User's Manual. University of Torino, Turin, Italy, 1999) ab initio program and a visualization system for the WIEN97 (Blaha, P., et al. Comput. Phys. Commun. 1990, 59, 399) ab initio program. In this article the program functions are presented with a short description of the algorithms.


Assuntos
Cristalografia por Raios X/métodos , Modelos Moleculares , Software , Simulação por Computador , Oxigênio/química , Platina/química
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