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61.
62.
Throughout the last century the increasing human activities in Antarctic region, particularly research expeditions, fishing, and tourism amplified the risk of oils spills at these high latitudes of the meridional hemisphere. A number of studies have been focused on chronic hydrocarbon contamination near Antarctic research stations revealing the presence and persistence of these human-derived contaminants. Marine ship-source oil spills in Antarctic region can have significant impacts on the marine environment. The key factors to effectively fight oil spills are a careful selection and proper use of the equipment and materials best suited to the critical local conditions. Despite the significant advances in the field of environmental recovery after an “oil spill” episode, research has recently shown that the usual techniques are often less effective than expected. This issue become much more relevant in the Antarctic case, not only for the incomparable environmental value of the Antarctic region but also for the extreme environmental conditions and the great distances from properly equipped centers, that make unfeasible sending naval vessels. Scope of the STRANgE Project is the preliminary design of a prototype floating platform, parachutable by plane, able to intervene as quickly as possible for the containment, removal and treatment/storage of the oil slick. New sorbent nanostructured materials and specialized Antarctic bacteria applications constitute the main innovations of this Project.  相似文献   
63.
In a companion paper, we described a theoretical foundation for and initial experimental implementation of a novel stereo-digital image correlation (DIC) method for quantifying the size, shape and deformation of small cylindrical specimens along their full length and around their entire circumference. In this paper, we further show that this panoramic-DIC method can be used to study mouse carotid arteries without affecting their native mechanical properties and show the advantage of the approach in studying more complex mouse aorta. In particular, we first resolve the ubiquitous issue of refraction in non-contacting optical measurements of strain while tissues are immersed in physiologic saline and we show that surface preparation for DIC does not affect the inferred mechanical properties either qualitatively or quantitatively, the latter via the use of a four-fibre family hyperelastic constitutive relation and associated estimation of material parameters using nonlinear regression. We thus submit that panoramic-DIC-based strain measurement has significant potential to increase our understanding of arterial mechanics in genetic models of arterial health and disease by allowing investigators to exploit advances in transgenic mice.  相似文献   
64.
Anthocyanins are a group of naturally occuring phenolic compounds related to the coloring of plants, flowers and fruits. These pigments are important as quality indicators, as chemotaxonomic markers and for their antioxidant activities. Here, we have investigated the therapeutic efficacy of anthocyanins contained in blackberry extract (cyanidin-3-O-glucoside represents about 80% of the total anthocyanin contents) in an experimental model of lung inflammation induced by carrageenan in rats. Injection of carrageenan into the pleural cavity elicited an acute inflammatory response characterized by fluid accumulation which contained a large number of neutrophils as well as an infiltration of polymorphonuclear leukocytes in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NOx) and prostaglandin E2 (PGE2). All parameters of inflammation were attenuated in a dose-dependent manner by anthocyanins (10, 30 mg kg-1 30 min before carrageenan). Furthermore, carrageenan induced an upregulation of the adhesion molecule ICAM-1, nitrotyrosine and poly (ADP-ribose) synthetase (PARS) as determined by immunohistochemical analysis of lung tissues. The degree of staining was lowered by anthocyanins treatment. Thus, the anthocyanins contained in the blackberry extract exert multiple protective effects in carrageenan-induced pleurisy.  相似文献   
65.
In a companion paper, we described a theoretical foundation for and initial experimental implementation of a novel stereo-digital image correlation (DIC) method for quantifying the size, shape and deformation of small cylindrical specimens along their full length and around their entire circumference. In this paper, we further show that this panoramic-DIC method can be used to study mouse carotid arteries without affecting their native mechanical properties and show the advantage of the approach in studying more complex mouse aorta. In particular, we first resolve the ubiquitous issue of refraction in non-contacting optical measurements of strain while tissues are immersed in physiologic saline and we show that surface preparation for DIC does not affect the inferred mechanical properties either qualitatively or quantitatively, the latter via the use of a four-fibre family hyperelastic constitutive relation and associated estimation of material parameters using nonlinear regression. We thus submit that panoramic-DIC-based strain measurement has significant potential to increase our understanding of arterial mechanics in genetic models of arterial health and disease by allowing investigators to exploit advances in transgenic mice.  相似文献   
66.
67.
Myocardial infarction and its consequences represent one of the most demanding challenges in cell therapy and regenerative medicine. Transfer of skeletal myoblasts into decompensated hearts has been performed through intramyocardial injection. However, the achievements of both cardiomyocyte differentiation and precise integration of the injected cells into the myocardial wall, in order to augment synchronized contractility and avoid potentially life‐threatening alterations in the electrical conduction of the heart, still remain a major target to be pursued. Recently, granulocytes colony‐stimulating factor (G‐CSF) fuelled the interest of researchers for its direct effect on cardiomyocytes, inhibiting both apoptosis and remodelling in the failing heart and protecting from ventricular arrhythmias through the up‐regulation of connexin 43 (Cx43). We propose a tissue engineering approach concerning the fabrication of an electrospun cardiac graft functionalized with G‐CSF, in order to provide the correct signalling sequence to orientate myoblast differentiation and exert important systemic and local effects, positively modulating the infarction microenvironment. Poly‐(l ‐lactide) electrospun scaffolds were seeded with C2C12 murine skeletal myoblast for 48 hrs. Biological assays demonstrated the induction of Cx43 expression along with morphostructural changes resulting in cell elongation and appearance of cellular junctions resembling the usual cardiomyocyte arrangement at the ultrastructural level. The possibility of fabricating extracellular matrix‐mimicking scaffolds able to promote myoblast pre‐commitment towards myocardiocyte lineage and mitigate the hazardous environment of the damaged myocardium represents an interesting strategy in cardiac tissue engineering.  相似文献   
68.
The survival of early stages of small pelagic fish species (e.g. Engraulis encrasicolus) is highly dependent on environmental conditions in both spawning and nursery areas. Knowing the relationship between the mortality rates of the early stages and the environment may help to study and model recruitment fluctuations. During the summer of 2006, two consecutive oceanographic cruises were carried out in the Central Mediterranean sea (CMED) in two different areas: the western Libyan waters and the Sicilian?CMaltese waters. For the first time a nearly synoptic comparison between the two border areas of the CMED is performed. In spite of a higher overall egg density in the Sicilian?CMaltese waters, there was a higher density of anchovy larvae in Libyan waters. The comparison between the oceanographic datasets singled out different circulation patterns and different characteristics of water masses, which helped to explain the differences in density of the spawning products in the two areas. A Lagrangian transport model was used to evaluate the effects of major oceanographic features on offshore egg and larval transport. The results of the model simulations and the nutritional conditions, as indicated by lipid, carbohydrate and protein contents, support the hypothesis that the western Libyan waters may represent a more favourable nursery ground compared to the Sicilian?CMaltese waters in terms of environmental conditions and food availability.  相似文献   
69.

Background

Traumatic brain injury (TBI) initiates a neuroinflammatory cascade that contributes to neuronal damage and behavioral impairment. Toll-like receptors (TLRs) are signaling receptors in the innate immune system, although emerging evidence indicates their role in brain injury. We have therefore investigated the role played by TLR4 signaling pathway in the development of mechanisms of secondary inflammatory process in traumatic brain injury (TBI) differ in mice that lack a functional TLR4 signaling pathway.

Methods/Principal Findings

Controlled cortical impact injury was performed on TLR4 knockout (KO) mice (C57BL/10ScNJ) and wild-type (WT) mice (C57BL/10ScNJ). TBI outcome was evaluated by determination of infarct volume and assessment of neurological scores. Brains were collected at 24 h after TBI. When compared to WT mice, TLR4 KO mice had lower infarct volumes and better outcomes in neurological and behavioral tests (evaluated by EBST and rotarod test). Mice that lacked TLR4 had minor expression of TBI-induced GFAP, Chymase, Tryptase, IL-1β, iNOS, PARP and Nitrotyrosine mediators implicated in brain damage. The translocation of expression of p-JNK, IκB-α and NF-κB pathway were also lower in brains from TLR4 KO mice. When compared to WT mice, resulted in significant augmentation of all the above described parameters. In addition, apoptosis levels in TLR4 KO mice had minor expression of Bax while on the contrary with Bcl-2.

Conclusions/Significance

Our results clearly demonstrated that absence of TLR4 reduces the development of neuroinflammation, tissues injury events associated with brain trauma and may play a neuroprotective role in TBI in mice.  相似文献   
70.
Boropinic acid is a natural isopentenyloxycinnamic acid extracted from the aerial parts of Boronia pinnata Sm. (Rutaceae) with soybean 5-lipoxygenase inhibitory activity. In this paper the topical anti-inflammatory activity of boropinic acid and some of its natural and semi-synthetic derivatives was evaluated using the Croton oil ear test in mice as a model of acute inflammation. Some of the tested compounds (15, 17, 19, 20) revealed an effect comparable (ID50 = 0.18 ÷ 0.72 μmol/cm2) to that of the reference drug indomethacin (ID50 = 0.23 μmol/cm2), a non-steroidal anti-inflammatory drug.  相似文献   
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