20 research outputs found

    IL-10 transcription is negatively regulated by BAF180, a component of the SWI/SNF chromatin remodeling enzyme

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    <p>Abstract</p> <p>Background</p> <p>SWI/SNF chromatin remodeling enzymes play a critical role in the development of T helper lymphocytes, including Th2 cells, and directly program chromatin structure at Th2 cytokine genes. Different versions of SWI/SNF complexes, including BAF and PBAF, have been described based on unique subunit composition. However, the relative role of BAF and PBAF in Th cell function and cytokine expression has not been reported.</p> <p>Results</p> <p>Here we examine the role of the PBAF SWI/SNF complex in Th cell development and gene expression using mice deficient for a PBAF-specific component, BAF180. We find that T cell development in the thymus and lymphoid periphery is largely normal when the BAF180 gene is deleted late in thymic development. However, BAF180-deficient Th2 cells express high levels of the immunoregulatory cytokine IL-10. BAF180 binds directly to regulatory elements in the Il-10 locus but is replaced by BAF250 BAF complexes in the absence of BAF180, resulting in increased histone acetylation and CBP recruitment to the IL-10 locus.</p> <p>Conclusions</p> <p>These results demonstrate that BAF180 is a repressor of IL-10 transcription in Th2 cells and suggest that the differential recruitment of different SWI/SNF subtypes can have direct consequences on chromatin structure and gene transcription.</p

    Bat guano as new and attractive chitin and chitosan source

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    WOS: 000340918700001Introduction: Chitin is a biopolymer that forms the exoskeleton of arthropods, and is found in the cell walls of fungi. It has a wide range of uses in fields such as cosmetics, pharmacy, medicine, bioengineering, agriculture, textiles and environmental engineering based upon its nontoxic, ecofriendly, biocompability and biodegradability characteristics. Commercially, chitin is obtained from processing the outer skeleton of Crustacea such as shrimp, crab, prawn and crayfish after they have been consumed as food. The study aims to examine the nature of bat guano and to determine if it is a practical source of chitin, which has not been done previously. Results: In this study, the chitin content of dry bat guano samples was found to be 28%. The bat guano, which was collected from Karacamal Cave, came from the bat species Rhinolophus hipposideros. The chitosan yield of this chitin was 79%. The chitin produced from the bat guano was determined to be in the alpha form according to Fourier transform infrared spectroscopy (FTIR) results. The crystallinity of the chitin and chitosan samples was calculated as 85.49 and 58.51% respectively by X-ray crystallography (XRD) experiments. According to scanning electron microscope (SEM) micrographs, the chitin and chitosan structures were shaped like nanofibers. The thermogravimetric analysis (TGA) results showed that both chitin and chitosan had two step weight losses, which are characteristic of these materials. The nitrogen content of the chitin and chitosan was 6.47 and 7.3% respectively according to the elemental analysis results. Conclusions: In this research, it has been observed that bat guano can be considered to be an alternative source of chitin and chitosan to crab, shrimp, crayfish and krill.Aksaray University BAP [2014-005]We would like to thank Prof. Dr. Ahmet KARATAS for bat species identification. This study was funded by Aksaray University BAP (2014-005)

    Krebs durch chemische Stoffe

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    Mesolithic human occupation and seasonality: sclerochronology, δ18O isotope geochemistry, and diagenesis verification by Raman and LA-ICP-MS analysis of Argyrosomus regius (meagre) sagittae otoliths from layer 1 of Cabeço da Amoreira Mesolithic shell midden (Muge, Portugal)

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