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31.
Here we have characterized perthamide C, a cyclopeptide from a Solomon Lithistid sponge Theonella swinhoei, which displays an anti-inflammatory/immunomodulatory activity. The study has been performed using the carragenan-induced mouse paw edema that displays an early (0–6 h) and a late phase (24–96 h). Perthamide C significantly inhibits neutrophils infiltration in tissue both in the early and late phases. This effect was coupled to a reduced expression of the endothelial nitric oxide synthase (eNOS) in the early phase while cyclooxygenase-1 and 2 (COX-1, COX-2), and inducible NOS (iNOS) expression were unaffected. In the late phase perthamide C reduced expression of both NOS isoforms without affecting COXs expression. This peculiar selectivity toward the two enzymes deputed to produce NO lead us to investigate on a possible action of perthamide C on lymphocytes infiltration and activation. We found that perthamide C inhibited the proliferation of peripheral lymphocytes, and that this effect was secondary to its metabolic activation in vivo. Indeed, in vitro perthamide C did not inhibit proliferation as opposite to its metabolite perthamide H.In conclusion, perthamide C selectively interferes with NO generation triggered by either eNOS or iNOS without affecting either COX-1 or COX-2. This in turn leads to modulation of the inflammatory response through a reduction of vascular permeability, neutrophil infiltration as well as lymphocyte proliferation.  相似文献   
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A bench-scale horizontal-flow anaerobic immobilized sludge (HAIS) reactor filled with porous ceramic spheres (5?mm diameter) was used for evaluating the effects of the tracer characteristics on the residence time distribution (RTD) curves and on the parameters of the hydrodynamic mathematical models. Stimulus-response assays were carried out with bromophenol blue, dextran blue, eosin Y, mordant violet, rhodamine WT and bromocresol green as tracers. The reactor was operated at the hydraulic residence time (HRT) of approximately 2 hours and the flow characteristics were evaluated by fitting the single-parameter models of dispersion and N-continuous stirred tank reactors (CSTR) in series to the experimental data. Tracer characteristics were found to affect deeply the form of RTD curves and the apparent degree of mixing observed in the responses were attributed to the tracer diffusion into the porous media, except for dextran blue. The best adjustment was obtained for the N-CSTR in series model. Thereafter, dextran blue and rhodamine WT were used in hydrodynamic experiments in the HAIS reactor operating with additional residence times. Values of N ranging from 34 to 62 were obtained from the dextran blue experiments for HRT ranging from 2 to 7 hours. The application of the statistical analysis ANOVA one-way method indicated that there was no significant statistical difference in the flow-pattern within the range of hydraulic residence times applied. The mean N value of 9 was obtained from the experiments with rhodamine WT. Such disagreement in the responses was attributed to the diffusion of rhodamine WT into the porous media, interfering in the shape of the experimental curves.  相似文献   
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Purinergic Signalling - Bone marrow (BM) as an active hematopoietic organ is highly sensitive to changes in body microenvironments and responds to external physical stimuli from the surrounding...  相似文献   
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The development of drugs able to target BTK, PI3k‐delta and BCL2 has dramatically improved chronic lymphocytic leukaemia (CLL) therapies. However, drug resistance to these therapies has already been reported due to non‐recurrent changes in oncogenic pathways and genes expression signatures. In this study, we investigated the cooperative role of the BCL2 inhibitor venetoclax and the BRD4 inhibitor JQ1. In particular, we found that JQ1 shows additional activity with venetoclax, in CLL cell lines and in ex vivo isolated primary CD19+ lymphocytes, arguing in favour of combination strategies. Lastly, JQ1 is also effective in venetoclax‐resistant CLL cell lines. Together, our findings indicated that the BET inhibitor JQ1 could be a promising therapy in CLL, both as first‐line therapy in combination with venetoclax and as second‐line therapy, after the emergence of venetoclax‐resistant clones.  相似文献   
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A multidisciplinary approach was carried out in order to study the biodeterioration and the associated microbiome of a XVIII Century wax seal coloured with minium. A small wax seal fragment was observed by scanning electron microscopy combined with energy dispersive spectroscopy in non-destructive mode. The same object was analysed by Raman and Fourier-transform infrared spectroscopy. The identification of the microbiota growing on the seal was performed with both a culture-dependent strategy, combined with hydrolytic assays, and high-throughput sequencing using the MinION platform. The whole bacterial 16S rRNA gene and the fungal markers ITS and 28S rRNA were targeted. It was observed that the carnauba wax coloured with lead tetroxide (minium) was covered by a biofilm consisting of a network of filaments and other structures of microbial origin. The culture-dependent and culture-independent investigations showed the presence of a complex microbiota composed mainly by fungal members, which demonstrated interesting properties related to lipids and lead processing. The formation of lead soaps and secondary biogenic minerals was also described.  相似文献   
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The International Journal of Life Cycle Assessment - Weighting in life cycle assessment (LCA) incorporates stakeholder preferences in the decision-making process of comparative LCAs. Research...  相似文献   
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The International Journal of Life Cycle Assessment - Current patterns of household goods consumption generate relevant environmental pressures and impacts. Environmental impacts are not only...  相似文献   
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