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321.
The International Journal of Life Cycle Assessment - The assessment of potential environmental impacts associated to mineral resource use in LCA is a highly debated topic. Most current...  相似文献   
322.
The increased risk of thromboembolism and higher incidence of cardiovascular disorders are among the most common causes of morbidity in patients suffering from autoimmune diseases. In this study we tested the hypothesis that IL-17A, a key pro-inflammatory cytokine involved in the development of autoimmune diseases, exerts pro-aggregant effects on both human and mouse platelets. Human or murine platelets were incubated with IL-17A for 2 min at 37 °C prior the addition of the stimuli. Aggregation was monitored in a light transmission aggregometer measuring changes in turbidity with continuous observation over a 5-min interval after the addition of the stimuli. IL-17RA, CD42b and CD62P expression as well as fibrinogen bindings were measured by FACS while Erk-2 phosphorylation was analyzed by western blot using phospho-specific antibodies. Pre-incubation with IL-17A increased ADP-, but not collagen-induced platelet aggregation and accelerated CD62P expression and exposure of fibrinogen binding sites. These effects were associated with a faster kinetic of ADP-induced Erk-2 phosphorylation and were lost in platelets deficient in the IL-17 receptor. Together these results unveil a novel aspect of the inflammatory nature of IL-17A suggesting, at the same time, that therapeutic strategies targeting this cytokine might provide further benefit for the treatment of autoimmune diseases by reducing the risk of cardiovascular-related pathologies.  相似文献   
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The genetic manipulation of the microbial community associated with hematophagus insects is particularly relevant for public health applications. Within mosquito populations, this relationship has been overlooked until recently. New advances in molecular biotechnology propose the genetic manipulation of mosquito symbionts to prevent the transmission of pathogens to humans by interfering with the obligatory life cycle stages within the insect through the use of effector molecules. This approach, defined as 'paratransgenesis', has opened the way for the investigation and characterization of microbes residing in the mosquito body, particularly those localised within the gut. Some interesting bacteria have been identified as candidates for genetic modification, however, endosymbiotic yeasts remain largely unexplored with little information on the symbiotic relationships to date. Here we review the recent report of symbiotic relationship between Wickerhamomyces anomalus (Pichia anomala) and several mosquito vector species as promising methods to implement control of mosquito-borne diseases.  相似文献   
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A key transducer in energy conservation and signaling cell death is the mitochondrial H+‐ATP synthase. The expression of the ATPase inhibitory factor 1 (IF1) is a strategy used by cancer cells to inhibit the activity of the H+‐ATP synthase to generate a ROS signal that switches on cellular programs of survival. We have generated a mouse model expressing a mutant of human IF1 in brain neurons to assess the role of the H+‐ATP synthase in cell death in vivo. The expression of hIF1 inhibits the activity of oxidative phosphorylation and mediates the shift of neurons to an enhanced aerobic glycolysis. Metabolic reprogramming induces brain preconditioning affording protection against quinolinic acid‐induced excitotoxicity. Mechanistically, preconditioning involves the activation of the Akt/p70S6K and PARP repair pathways and Bcl‐xL protection from cell death. Overall, our findings provide the first in vivo evidence highlighting the H+‐ATP synthase as a target to prevent neuronal cell death.  相似文献   
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Membrane junctions or contact sites are close associations of lipid bilayers of heterologous organelles. Ist2 is an endoplasmic reticulum (ER)‐resident transmembrane protein that mediates associations between the plasma membrane (PM) and the cortical ER (cER) in baker's yeast. We asked the question what structure in Ist2 bridges the up to 30 nm distance between the PM and the cER and we noted that the region spacing the transmembrane domain from the cortical sorting signal interacting with the PM is predicted to be intrinsically disordered (ID). In Ssy1, a protein that was not previously described to reside at membrane junctions, we recognized a domain organization similar to that in Ist2. We found that the localization of both Ist2 and Ssy1 at the cell periphery depends on the presence of a PM‐binding domain, an ID linker region of sufficient length and a transmembrane domain that most probably resides in the ER. We show for the first time that an ID amino acid domain bridges adjacent heterologous membranes. The length and flexibility of ID domains make them uniquely eligible for spanning large distances, and we suggest that this domain structure occurs more frequently in proteins that mediate the formation of membrane contact sites.   相似文献   
328.
A facile and low‐temperature (125 °C) solution‐processed Al‐doped ZnO (AZO) buffer layer functioning very effectively as electron accepting/hole blocking layer for a wide range of polymer:fullerene bulk heterojunction systems, yielding power conversion efficiency in excess of 10% (8%) on glass (plastic) substrates is described. The ammonia‐treatment of the aqueous AZO nanoparticle solution produces compact, crystalline, and smooth thin films, which retain the aluminum doping, and eliminates/reduces the native defects by nitrogen incorporation, making them good electron transporters and energetically matched with the fullerene acceptor. It is demonstrated that highly efficient solar cells can be achieved without the need for additional surface chemical modifications of the buffer layer, which is a common requirement for many metal oxide buffer layers to yield efficient solar cells. Also highly efficient solar cells are achieved with thick AZO films (>50 nm), highlighting the suitability of this material for roll‐to‐roll coating. Preliminary results on the applicability of AZO as electron injection layer in F8BT‐based polymer light emitting diode are also presented.  相似文献   
329.
Tetanus and botulinum neurotoxins cause paralysis by cleaving SNARE proteins within the cytosol of nerve terminals. They are endocytosed inside acidic vesicles and the pH gradient across the membrane drives the translocation of their metalloprotease L domain in the cytosol. This domain is linked to the rest of the molecule by a single interchain disulfide bridge that has to be reduced on the cytosolic side of the membrane to free its enzymatic activity. By using specific inhibitors of the various cytosolic protein disulfides reducing systems, we show here that the NADPH-thioredoxin reductase-thioredoxin redox system is the main responsible for this disulfide reduction. In addition, we indicate auranofin, as a possible basis for the design of novel inhibitors of these neurotoxins.  相似文献   
330.
Oxidative stress has been related to ageing and risk of death. To determine whether oxidative status was associated with all-cause risk of death we carried out a prospective study in 154 non-smoking Spanish elderly without major illness. Baseline glutathione peroxidase (GPx) and superoxide dismutase (SOD) were analysed in plasma and erythrocytes. α-tocopherol, β-carotene, lycopene and retinol were determined in serum samples and malondialdehyde (MDA), as a lipid peroxidation marker, in plasma. Mean survival time was 4.3 years. A total of 31 death cases (20.1%) occurred during the follow-up. Plasma-MDA predicted mortality independently of all other variables, while erythrocyte-SOD (e-SOD), β-carotene and α-tocopherol were positively associated with survival. α-tocopherol and MDA were revealed as independent predictors in a joint survival model, being the group with low MDA and high α-tocopherol that with the lowest mortality. In conclusion, a higher risk of death was associated with increased lipid peroxidation and lower antioxidant defenses.  相似文献   
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