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Background: Although Desulfovibrio desulfuricans species, besides existing in the natural environment, is also found in the human digestive tract, no information is currently available on its role in the intestinal ecosystem and its activity in regard to the intestinal mucosa. Bacterial products (lipopolysaccharides, LPSs) are generally known for their ability to trigger inflammatory response by stimulating cytokine expression, such as interleukin-8 (IL-8). Methods: Colonic Caco-2 cells were exposed to LPSs isolated from the soil type and intestinal wild strains of D. desulfuricans bacteria. The amount of IL-8 secreted was measured by ELISA. The effects of sodium butyrate and cell preincubation with sodium butyrate on the IL-8 secretion in response to LPSs were also analysed. Results: LPSs from D. desulfuricans down-regulated IL-8 secretion by the cells. Incubation of these cells with butyrate alone resulted in a dose-dependent stimulation of IL-8 release. Butyrate also modulated IL-8 secretion by cells stimulated with LPSs. Conclusions: Our findings suggest the lack of inflammatory response of intestinal mucosa in the presence of LPSs of D. desulfuricans. This response can be conditioned by the natural bacterial product, butyrate, which exerts a stimulatory effect on the IL-8 secretion and modulates its release in response to LPSs.  相似文献   
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Electron‐acceptor units, combined with bithiophene substituted with flexible chains end‐functionalized with cross‐linkable moieties, provide soluble donor‐acceptor‐donor (DAD) π‐conjugated oligomer‐type molecules with cross‐linking ability and broad absorption in the visible spectrum. A study on the cross‐linking conditions of the new oligomers to yield insoluble polymer networks is presented, including conditions for obtaining polymer films over poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate‐covered substrates. The combination of the DAD molecular design and cross‐linking functionality opens prospects for applications in solution‐processed small‐molecule solar cells with morphologically‐stable organic layers.

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Here we report a patient with 11p15.4p15.5 duplication and 13q34 deletion presenting with Beckwith–Wiedemann syndrome (BWS) and moderate deficiency of factor VII (FVII). The duplication was initially diagnosed on methylation‐sensitive multiplex ligation‐dependent probe amplification. Array comparative genome hybridization confirmed its presence and indicated a 13q34 distal deletion. The patient's clinical symptoms, including developmental delay and facial dysmorphism, were typical of BWS with paternal 11p15 trisomy. Partial 13q monosomy in this patient is associated with moderate deficiency of FVII and may also overlap with a few symptoms of paternal 11p15 trisomy such as developmental delay and some facial features. To our knowledge this is the first report of 11p15.4p15.5 duplication associated with deletion of 13q34 and FVII deficiency. Moreover, this report emphasizes the importance of detailed clinical as well as molecular examinations in patients with BWS features and developmental delay.  相似文献   
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aHUS is a clinical challenge for successful renal transplantation. Case report: A 14‐yr‐old girl lost her kidneys at the age of 7, due to CFH antibodies and CFH‐related protein (CFHR1/CFHR3) homozygous deletion‐associated aHUS. CFH, CFI, and MCP gene mutations were excluded. The patient was a candidate for renal transplantation despite persistent presence of CFH antibodies (up to 539 AU/mL). Treatment with MMF, IVIG, and repeated PF (n = 8) was introduced while being placed on urgent waiting list. Three years after aHUS onset, the patient underwent the deceased donor renal transplantation “under cover” of PF, as PF was performed directly prior to surgery and, then, PFs were repeated up to overall 14 sessions. Quadruple immunosuppression (basiliximab + tacrolimus + MMF + prednisolone) was used. Moderate symptoms of aHUS (hemolysis, low platelets, and low C3) were present within first seven days post‐transplant and then normalized with PF therapy. The patient remained stable during four yr of further follow‐up after transplantation. Conclusion: Specific pre‐ and post‐transplant management allowed successful renal transplantation in a CFH antibody‐positive patient.  相似文献   
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