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    Embedding of global attractors and their dynamics

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    Using shape theory and the concept of cellularity, we show that if AA is the global attractor associated with a dissipative partial differential equation in a real Hilbert space HH and the set AAA-A has finite Assouad dimension dd, then there is an ordinary differential equation in Rm+1{\mathbb R}^{m+1}, with m>dm >d, that has unique solutions and reproduces the dynamics on AA. Moreover, the dynamical system generated by this new ordinary differential equation has a global attractor XX arbitrarily close to LALA, where LL is a homeomorphism from AA into Rm+1{\mathbb R}^{m+1}

    3,7-Bis(dialkylamino)phenothiazin-5-ium derivatives: biomedical applications and biological activity

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    The light-induced reactions of 3,7-bis(dialkylamino)phenothiazin-5-ium compounds with biological substrates are briefly discussed. Their biomedical applications, in particular those related with biological staining, interaction with proteins and antiviral, antibacterial and antitumour activity are reviewed.info:eu-repo/semantics/publishedVersio

    The gut microbiota, bile acids and their correlation in primary sclerosing cholangitis associated with inflammatory bowel disease.

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    BACKGROUND: Patients with primary sclerosing cholangitis associated with inflammatory bowel disease (PSC-IBD) have a very high risk of developing colorectal neoplasia. Alterations in the gut microbiota and/or gut bile acids could account for the increase in this risk. However, no studies have yet investigated the net result of cholestasis and a potentially altered bile acid pool interacting with a dysbiotic gut flora in the inflamed colon of PSC-IBD. AIM: The aim of this study was to compare the gut microbiota and stool bile acid profiles, as well as and their correlation in patients with PSC-IBD and inflammatory bowel disease alone. METHODS: Thirty patients with extensive colitis (15 with concomitant primary sclerosing cholangitis) were prospectively recruited and fresh stool samples were collected. The microbiota composition in stool was profiled using bacterial 16S rRNA sequencing. Stool bile acids were assessed by high-performance liquid chromatography tandem mass spectrometry. RESULTS: The total stool bile acid pool was significantly reduced in PSC-IBD. Although no major differences were observed in the individual bile acid species in stool, their overall combination allowed a good separation between PSC-IBD and inflammatory bowel disease. Compared with inflammatory bowel disease alone, PSC-IBD patients demonstrated a different gut microbiota composition with enrichment in Ruminococcus and Fusobacterium genus compared with inflammatory bowel disease. At the operational taxonomic unit level major shifts were observed within the Firmicutes (73%) and Bacteroidetes phyla (17%). Specific microbiota-bile acid correlations were observed in PSC-IBD, where 12% of the operational taxonomic units strongly correlated with stool bile acids, compared with only 0.4% in non-PSC-IBD. CONCLUSIONS: Patients with PSC-IBD had distinct microbiota and microbiota-stool bile acid correlations as compared with inflammatory bowel disease. Whether these changes are associated with, or may predispose to, an increased risk of colorectal neoplasia needs to be further clarified.info:eu-repo/semantics/publishedVersio
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