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991.
Daniela Ligi Sonia Benitez Lidia Croce Andrea Rivas-Urbina Núria Puig Jordi Ordóñez-Llanos Ferdinando Mannello Jose Luis Sanchez-Quesada 《生物化学与生物物理学报:疾病的分子基础》2018,1864(12):3559-3567
Objective
Electronegative LDL (LDL(?)) is involved in atherosclerosis through the activation of the TLR4/CD14 inflammatory pathway in monocytes. Matrix metalloproteinases (MMP) and their inhibitors (tissue inhibitors of metalloproteinase [TIMP]) are also crucially involved in atherosclerosis, but their modulation by LDL(?) has never been investigated. The aim of this study was to examine the ability of LDL(?) to release MMPs and TIMPs in human monocytes and to determine whether sulodexide (SDX), a glycosaminoglycan-based drug, was able to affect their secretion.Approach and results
Native LDL (LDL(+)) and LDL(?) separated by anion-exchange chromatography were added to THP1-CD14 monocytes in the presence or absence of SDX for 24?h. A panel of 9 MMPs and 4 TIMPs was analyzed in cell supernatants with multiplex immunoassays. The gelatinolytic activity of MMP-9 was assessed by gelatin zymography. LDL(?) stimulated the release of MMP-9 (13-fold) and TIMP-1 (4-fold) in THP1-CD14 monocytes, as well as the gelatinolytic activity of MMP-9. Co-incubation of monocytes with LDL(?) and SDX for 24?h significantly reduced both the release of MMP-9 and TIMP-1 and gelatinase activity. In THP1 cells not expressing CD14, no effect of LDL(?) on MMP-9 or TIMP-1 release was observed. The uptake of DiI-labeled LDL(?) was higher than that of DiI-LDL(+) in THP1-CD14 but not in THP1 cells. This increase was inhibited by SDX. Experiments in microtiter wells coated with SDX demonstrated a specific interaction of LDL(?) with SDX.Conclusions
LDL(?) induced the release of MMP-9 and TIMP-1 in monocytes through CD14. SDX affects the ability of LDL(?) to promote TIMP-1 and MMP-9 release by its interaction with LDL(?). 相似文献992.
Pedro Villanueva-Rey Ian Vázquez-Rowe Andrea Arias Maria Teresa Moreira Gumersindo Feijoo 《The International Journal of Life Cycle Assessment》2018,23(5):1091-1106
Purpose
Drift net fishing activities have undergone a thorough revision at a European Union level, since authorities argue that several loopholes still exist in the legislation that allow small-scale fisheries to use these gears. High incidental catches, or the lack of selectivity, are some of the primary scientific criteria behind this discussion. This new framework is of particular interest in the region of Galicia (NW Spain) due to the social importance of small-scale fishing vessels using drift nets. In fact, over 400 vessels have a licence to capture European pilchard (Sardina pilchardus) with a fishing gear called xeito, which is a small-scale drift net.Methods
The main goal of this article is to provide stakeholders in the fishing sector with environmentally relevant results regarding the life cycle impacts linked to fishing practices performed by small-scale vessels using the xeito gear to target European pilchard. We hypothesize that environmental impacts computed with LCA will provide additional insights to the sustainability of the pilchard small-scale fishery in NW Spain, adding a series of criteria that may be useful for policy-makers to determine the consequences of forbidding this type of drift netting in the future.Results and discussion
Results show that environmental impacts across impact categories and operational activities do not differ much from that of other similar fishing fleets examined in recent years, with fuel for propulsion being the main environmental burden in most impact categories. When conducting a statistical analysis, no significant difference in energy use was identified between this small-scale fleet and purse seiners targeting pilchard in Galicia. Moreover, the results obtained demonstrate, in line with previous studies, that European pilchard is still an energy-efficient source of animal protein option as compared to demersal fish alternatives, crustaceans, or livestock.Conclusions
The results do not indicate that European pilchard landed with small-scale drift nets generates higher environmental life cycle impacts than pilchard landed by purse seiners in NW Spain. However, longer time frames for the analysis should be performed to attain results with lower uncertainty.993.
Isabel Martinez‐Sañudo Mauro Simonato Andrea Squartini Nicola Mori Laura Marri Luca Mazzon 《Insect Science》2018,25(5):833-846
The spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a highly polyphagous pest of a wide variety of wild or cultivated berry and stone fruit. Originating from Southeast Asia, it has recently invaded a wide range of regions in Europe and North America. It is well known that insect microbiotas may significantly influence several aspects of the host biology and play an important role in invasive species introduction into new areas. However, in spite of the great economic importance of D. suzukii, a limited attention has been given so far to its microbiota. In this study, we present the first in‐depth characterization of gut bacterial diversity from field (native and invasive range) and lab‐reared populations of this insect. The gut bacterial communities of field insects were dominated, regardless of their origin, by 2 families of the phylum Proteobacteria: Acetobacteraceae and Enterobacteriaceae, while Firmicutes, mainly represented by the family Staphylococcaceae, prevailed in lab‐reared population. Locality was the most significant factor in shaping the microbiota of wild flies. Moreover, a negative correlation between diversity and abundance of Enterobacteriaceae and the time elapsed since the establishment of D. suzukii in a new region was observed. Altogether our results indicate that habitat, food resources as well as the colonization phase of a new region contribute to shape the bacterial communities of the invasive species which, in turn, by evolving more quickly, could influence host adaptation in a new environment. 相似文献
994.
Markus Freick Andrea Konrath Haimo Enbergs Jörg Walraph Jim Weber Karin Eulenberger 《Folia microbiologica》2018,63(2):253-260
Coxiella burnetii (C. burnetii), an intracellular zoonotic bacterium causing Q fever, occurs widely in cattle herds. After invasion of the pregnant uterus and initial localization in the placenta, active C. burnetii infections may spread to the fetus hematogenously or by the amniotic-oral route and thus may cause abortion, premature delivery, stillbirth, and weak offspring (APSW) complex. In a case-control study, we investigated precolostral blood samples of 56 stillborn calves and 30 live births from a dairy herd endemically infected with C. burnetii “C-cluster” strains and an increased stillbirth rate in primiparous cows. Within the group of the stillborn calves, four precolostral blood samples (7.1%) were tested positive for C. burnetii DNA by PCR and one serum sample (1.8%) positive for anti-C. burnetii IgG antibodies by a commercial ELISA test, respectively. Neither C. burnetii DNA nor anti-C. burnetii IgG antibodies were detected in the samples of calves being born alive. In conclusion, we demonstrated that coxiellaemia and precolostral seroconversion occurred sporadically in stillborn calves from this endemically infected herd. Due to the low detection rates, C. burnetii could not be confirmed to be the cause of the increased stillbirth rate. 相似文献
995.
We analysed the mycorrhizal types of two coastal Mediterranean plant communities. Plants belonging to 82 species of 46 families growing in two Mediterranean study sites located within a Regional Natural Park in Italy (Macchia Lucchese) and in a National Park in Croatia (Brijuni) were assessed for the type of their mycorrhizal associations. Mycorrhizas occurred in 83% and 90% of the plant species surveyed in Macchia Lucchese and in Brijuni, respectively. On the basis of macroscopic and microscopic characteristics, six different mycorrhizal types were found, and their co-occurrence in the same plant community showed the large mycorrhizal diversity in Mediterranean vegetation. Different occurrence patterns of mycorrhizal types have been recognised in diverse habitats within Macchia Lucchese, from sand dune plant communities to sclerophyllous woodland. Mycorrhizal type abundance calculated on a floristic basis was very different from that obtained using a vegetation cover index. 相似文献
996.
Scotti C Iamele L Alessandrini A Vannini V Cazzalini O Lazzè MC Melli R Savio M Pizzala R Stivala LA Biglieri S Tomasi A Bianchi L 《Mitochondrion》2003,2(5):361-373
We investigated the molecular relationships between lipid peroxidation and mitochondrial DNA (mtDNA) single strand breaks (ssb) in isolated rat hepatocytes and mitochondria exposed to tert-butylhydroperoxide (TBH). Our results show that mtDNA ssb induced by TBH are independent of lipid peroxidation and dependent on the presence of iron and of hydroxyl free radicals. These data contribute to the definition of the mechanisms whereby mtDNA ssb are induced and provide possible molecular targets for the prevention of this kind of damage in vivo. 相似文献
997.
Serra PA Rocchitta G Delogu MR Migheli R Taras MG Mura MP Esposito G Miele E Desole MS Miele M 《Journal of neurochemistry》2003,86(6):1403-1413
In vitro microdialysis was used to investigate the mechanism of nitric oxide (NO) donor-induced changes in dopamine (DA) secretion from PC12 cells. Infusion of the NO-donor S-nitroso-N-acetylpenicillamine (SNAP, 1.0 mm) induced a long-lasting increase in DA and 3-methoxytyramine (3-MT) dialysate concentrations. SNAP-induced increases were inhibited either by pre-infusion of the soluble guanylate cyclase (sGC) inhibitor 1H-[1,2,4] oxadiazolo[4,3]quinoxalin-1-one (ODQ, 0.1 mm) or by Ca2+ omission. Ca2+ re-introduction restored SNAP effects. SNAP-induced increases in DA + 3-MT were unaffected by co-infusion of the l-type Ca2+ channel inhibitor nifedipine. The NO-donor (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR-3, 1.0 mm) induced a short-lasting decrease in dialysate DA + 3-MT. Ascorbic acid (0.2 mm) co-infusion allowed NOR-3 to increase dialysate DA + 3-MT. ODQ pre-infusion inhibited NOR-3 + ascorbic acid-induced DA + 3-MT increases. Infusion of high K+ (75 mm) induced a 2.5-fold increase in dialysate DA + 3-MT. The increase was abolished by NOR-3 co-infusion. Conversely, co-infusion of ascorbic acid (0.2 mm) with NOR-3 + high K+ restored high K+ effects. Co-infusion of nifedipine inhibited high K+-induced DA + 3-MT increases. These results suggest that activation of the NO/sGC/cyclic GMP pathway may be the underlying mechanism of extracellular Ca2+-dependent effects of exogenous NO on DA secretion from PC12 cells. Extracellular Ca2+ entry may occur through nifedipine-insensitive channels. NO effects and DA concentrations in dialysates largely depend on both the timing of NO generation and the extracellular environment in which NO is generated. 相似文献
998.
999.
Stephen L. Hicks Rakesh Sharma Amad N. Khan Claire M. Berna Andrea Waldecker Kevin Talbot Chris Kennard Martin R. Turner 《PloS one》2013,8(12)
The neurodegenerative disorder amyotrophic lateral sclerosis may render patients unable to speak or write, so that objective assessment of cognitive impairment, which is commonly of a dysexecutive nature, is challenging. There is therefore a need to develop other methods of assessment that utilize other relatively unaffected motor systems. In this proof-of-principle study a novel eye-tracking version of the trail-making test was compared with performance on the standard written version in a group of healthy volunteers. There was good correlation for speed between both versions of Part B (R2=0.73), suggesting that this is a viable method to objectively assess cognitive impairment in disorders where patients are unable to speak or write. 相似文献
1000.
Laura Pasin Giovanni Landoni Maria Lourdes Castro Luca Cabrini Alessandro Belletti Paolo Feltracco Gabriele Finco Andrea Carozzo Roberto Chiesa Alberto Zangrillo 《PloS one》2013,8(12)