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101.
The development and progression of colorectal cancer (CRC) have been associated with inflammation processes that involve the overactivation of the NF‐κB signalling pathway. The characterization of the NF‐κB expression profile in CRC is an important topic since the suppression of NF‐κB represents a potential therapeutic approach. In this study, we assessed the expression levels of 84 NF‐κB‐related genes in paired tumoral (T) and peritumoral (PT) tissues from 18 CRC patients and 18 normal colonic mucosae, and the expression levels of three miRNAs targeting the most dysregulated genes revealed by the case–control analysis. Comparing the gene expression profile of T and controls, 60 genes were dysregulated. The comparison of T and PT revealed 17 dysregulated genes in the tumoral tissues, with IL1B, CXCL8, IL1A, and CSF2 being the most upregulated. Notably, through a bioinformatics analysis, the differential gene expression of 11 out of the 17 genes was validated on a larger cohort of 308 CRC patients compared with 41 controls. Moreover, a decrease in the levels of RELA, NOD1, CASP8, BCL2L1, ELK1, and IKBKB was identified in poorly differentiated tumours compared to moderately differentiated tumours. The analysis of the three miRNAs targeting IL1B, CXCL8, IL1A, and CSF2 showed that miR‐182‐5p was upregulated in T compared with PT, whereas miR‐10b‐5p was downregulated in T compared with PT and control tissues. Our results may contribute to the design of new experimental therapeutic strategies based on endogenous molecules, such as miRNAs, to target the genetic key players of the NF‐ κB pathway.  相似文献   
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Extra-abdominal desmoid tumours are slow-growing, histologically benign tumours of fibroblastic origin with variable biologic behaviour. They are locally aggressive and invasive to surrounding anatomic structures. Magnetic resonance imaging is the modality of choice for the diagnosis and the evaluation of the tumours. Current management of desmoids involves a multidisciplinary approach. Wide margin surgical resection remains the main treatment modality for local control of the tumour. Amputation should not be the initial treatment, and function-preserving procedures should be the primary treatment goal. Adjuvant radiation therapy is recommended both for primary and recurrent lesions. Chemotherapy may be used for recurrent or unresectable disease. Overall local recurrence rates vary and depend on patient's age, tumour location and margins at resection.  相似文献   
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The identification of macrophyte reference communities represents a significant challenge in Mediterranean zones, where few aquatic taxa exist compared to other regions of the world. In the highly seasonal rivers of Portugal, we explored the contribution of bryophytes to enhance the compositional and ecological characterization of reference conditions. We performed partitioning, classification, and ordination analyses and obtained eight groups of bryophytic assemblages explained by water availability and quality. Groups A, B, and H assemblages are type-specific of the inland areas of the northern eco-region, reflecting the neutral minerotrophic currents with summer low currents. Groups C and D are type-specific of acidic oligotrophic shifting currents dependent of precipitation events in the mountainous streams of the North Atlantic eco-region. Groups E, F, and G are widespread in continental northern, central, and southern zones in neutral and highly mineralized watercourses with seasonal dryness. We propose bryophytes as a tool in the characterization of the reference conditions for two main reasons: (i) many of the recorded taxa are capable of withstanding the natural seasonal desiccation, and (ii) the type-specific bryophytes have perennial life-strategies and can be assessed at any time of year as a support for other type-specific macrophytes in compositional assessments of reference conditions.  相似文献   
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Protein conformational disorders are characterized by disruption of protein folding and toxic accumulation of protein aggregates. Here we describe a sensitive and simple method to follow and monitor general protein aggregation in human cells. Heat shock protein 27 (HSP27) is an oligomeric small heat shock protein that binds and keeps unfolded proteins in a folding competent state. This high specificity of HSP27 for aggregated proteins can be explored to monitor aggregation in living cells by fusing it to a fluorescent protein as Green Fluorescent Protein (GFP). We have constructed a HeLa stable cell line expressing a HSP27:GFP chimeric reporter protein and after validation, this stable cell line is exposed to different agents that interfere with proteostasis, namely Arsenite, MG132, and Aβ‐peptide. Exposure to proteome destabilizers lead to re‐localization of HSP27:GFP fluorescence to foci, confirming that our reporter system is functional and can be used to detect and follow protein aggregation in living cells. This reporter is a valuable tool to setup wide‐genetic screens to identify genes and pathways involved in protein misfolding and aggregation.  相似文献   
107.
A headspace gas chromatographic method using a fused-silica capillary column Poraplot Q has been developed and validated for the detection and quantification of ethanol in urine. Under optimized conditions, ethanol was properly separated from acetaldehyde, acetone, isopropanol, methanol and n-propanol. Limits of detection (LODs) and quantification (LOQs) were 0.008 and 0.010 g/l, respectively. The precision studies within-run and between-run, using spiked urine samples (0.08, 0.8 and 2.0 g/l) showed maximum coefficients of variation 5.9 and 6.5%, respectively. Results of ethanol recovery varied from 91.6±0.8 to 103.3±1.8% over the concentration range from 0.01 to 3.20 g/l. The method was appropriate for the detection of ethanol in urine samples. This matrix can be used for monitoring alcohol abuse in the workplace and used in alcohol rehabilitation programs.  相似文献   
108.
Genetically modified (GM) plants represent a potential benefit for environmentally friendly agriculture and human health. Though, poor knowledge is available on potential hazards posed by unintended modifications occurring during genetic manipulation. The increasing amount of reports on ecological risks and benefits of GM plants stresses the need for experimental works aimed at evaluating the impact of GM crops on natural and agro-ecosystems. Major environmental risks associated with GM crops include their potential impact on non-target soil microorganisms playing a fundamental role in crop residues degradation and in biogeochemical cycles. Recent works assessed the effects of GM crops on soil microbial communities on the basis of case-by-case studies, using multimodal experimental approaches involving different target and non-target organisms. Experimental evidences discussed in this review confirm that a precautionary approach should be adopted, by taking into account the risks associated with the unpredictability of transformation events, of their pleiotropic effects and of the fate of transgenes in natural and agro-ecosystems, weighing benefits against costs.  相似文献   
109.
BACKGROUND/AIM: The present study aimed at elucidating the mechanism(s) of serotonin (5-HT) efflux induced by thapsigargin from human platelets in the absence of extra-cellular Ca2+. METHODS: Efflux of pre-loaded radiolabeled serotonin was generally determined by filtration techniques. Cytosolic concentrations of Ca2+, Na+ and H+ were measured with appropriate fluorescent probes. RESULTS: 5-HT efflux from control or reserpine-treated platelets--where reserpine prevents 5-HT transport into the dense granules--was proportional to thapsigargin evoked cytosolic [Ca2+]c increase. Accordingly factors as prostacyclin, aspirin and calyculin which reduced [Ca2+]c-increase also inhibited the 5-HT efflux. Thapsigargin, which also caused a remarkable increase in cytosolic [Na+]c, promoted less 5-HT release, in parallel to lower [Na+]c and [Ca2+]c increase, when added to platelet suspensions containing low [Na+]. The Na+/H+ exchanger monensin increased the [Na+]c and induced 5-HT efflux without affecting the Ca2+ level. The 5-HT efflux induced by both [Ca2+] or [Na+]c increase did not depend on pH or membrane potential changes, whereas it decreased in the absence of extra-cellular K+, and increased in the absence of Cl- or Na+. CONCLUSION: Increases in [Ca2+]c and [Na+]c independently induce serotonin efflux through the outward directed plasma membrane serotonin transporter SERT. This event might be physiologically important at the level of capillaries or narrowed arteries where platelets are subjected to high shear stress which causes [Ca2+]c increase followed by 5-HT release which might exert vasodilatation.  相似文献   
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