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81.
CD47 on live cells actively engages signal-regulatory protein-alpha (SIRP-alpha) on phagocytes and delivers a negative signal that prevents their elimination. We evaluated the biological consequences of SIRP-alpha ligation on the dendritic cell (DC) response to maturation signals and the potential interplay with the IL-10/IL-10R inhibitory pathway. At first, CD47/SIRP-alpha allowed the generation of mature migratory DCs not producing IL-12, IFN-gamma-inducible protein-10, and CCL19. Rather, they secreted neutrophils attracting chemokine CXCL5 and IL-1beta, reflecting a partial block in functional DC maturation. Afterward, semimature DCs functionally regressed in an IL-10-independent fashion toward cells that retrieved the cardinal features of immature DCs: re-expression of CCR5, loss of DC-lysosome-associated membrane protein, high endocytosis, and impaired allostimulatory functions. The global gene expression profile of IL-10 and SIRP-alpha-ligated DC demonstrated two distinct molecular pathways. IL-10R and SIRP-alpha expression were reciprocally down-regulated by CD47 and IL-10, respectively. These results emphasize that the SIRP-alpha pathway might be part of the molecular machinery used by the DC to dampen or resolve an inflammatory response in an IL-10-independent manner.  相似文献   
82.
Long non-coding RNAs (ncRNA) have recently been demonstrated to be expressed from a subset of enhancers and to be required for the distant regulation of gene expression. Several approaches to predict enhancers have been developed based on various chromatin marks and occupancy of enhancer-binding proteins. Despite the rapid advances in the field, no consensus how to define tissue specific enhancers yet exists. Here, we identify 2,695 long ncRNAs annotated by ENCODE (corresponding to 28% of all ENCODE annotated long ncRNAs) that overlap tissue-specific enhancers. We use a recently developed algorithm to predict tissue-specific enhancers, PreSTIGE, that is based on the H3K4me1 mark and tissue specific expression of mRNAs. The expression of the long ncRNAs overlapping enhancers is significantly higher when the enhancer is predicted as active in a specific cell line, suggesting a general interdependency of active enhancers and expression of long ncRNAs. This dependency is not identified using previous enhancer prediction algorithms that do not account for expression of their downstream targets. The predicted enhancers that overlap annotated long ncRNAs generally have a lower ratio of H3K4me1 to H3K4me3, suggesting that enhancers expressing long ncRNAs might be associated with specific epigenetic marks. In conclusion, we demonstrate the tissue-specific predictive power of PreSTIGE and provide evidence for thousands of long ncRNAs that are expressed from active tissue-specific enhancers, suggesting a particularly important functional relationship between long ncRNAs and enhancer activity in determining tissue-specific gene expression.  相似文献   
83.
Flower buds of `Valencia' orange (Citrus sinensis [L.] Osbeck) were able to fix 14CO2 into a number of compounds in their own tissues under both light and dark conditions. The total incorporation, however, was about 4-fold higher in the light than in the dark. In the light, 50% of the total 14C label was found in the neutral fraction (sugars), 22% in the basic fraction (amino acids), and 26% in the acid-1 fraction (organic acids). In the dark, about 95% of the 14C label was incorporated into the basic and acid-1 fractions. Activities of ribulose bisphosphate carboxylase and phosphoenolpyruvate carboxylase (expressed in micromoles CO2 per milligram protein per hour) averaged 1.95 and 8.87 for the flower buds, and 28.5 and 3.6 for the leaves, respectively. The ability of orange flower buds to fix ambient CO2 into different compounds suggests that this CO2 assimilation may have some regulatory role during the early reproductive stages in determining citrus fruit initiation and setting.  相似文献   
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Polymorphism of genes encoding components of the vitamin D pathway including vitamin D receptor (VDR) and vitamin D binding protein (VDBP), have been widely explored due to the complex role played by vitamin D in renal transplant outcomes. In this study, we investigated whether polymorphisms of genes encoding VDR and VDBP were associated with allograft survival or acute rejection (AR) among a Hispanic kidney transplant population. A total of 502 Hispanic renal allograft recipients at the St. Vincent Medical Center between 2001 and 2010 were genotyped for four different single nucleotide polymorphisms of VDR: FokI C>T (rs2228570), BsmI G>A (rs1544410), ApaI T>G (rs7975232), and TaqI T>C (rs731236). We also performed genotyping for one common polymorphism in the VDBP gene (rs4588). Survival was significantly improved for patients who were homozygous GG for the rs4588 G>T allele in the VDBP gene (GG vs. GT + TT, OR = 0.63, p = 0.02) while GT genotype was associated with a higher risk of graft loss (GT vs. GG + TT, OR = 1.67, p = 0.01). We found no association for polymorphic markers in VDR with allograft survival and AR. The frequency of the haplotype GTCG (in the order of VDR FokI C>T, BsmI G>A, ApaI T>G, and TaqI T>C), was significantly different in the patients with graft rejection compared to the control (p = 0.007) while ACCA haplotype was found to be associated with graft loss (p = 0.02). Hence, the VDBP G>T polymorphism (rs4588) and two haplotypes (GTCG and ACCA) of VDR appear to be associated with renal allograft outcomes among Hispanic allograft recipients.  相似文献   
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The phylogenetic distributions ofσ- and phencyclidine receptors in neural tissues of 13 species and the pharmacological characteristics of these receptors in whole sea anemone and neural tissues of the guinea pig, chicken, and frog were studied. Specific binding of [3H]haloperidol and [3H]N-[1-(2-thienyl)cyclohexyl]-3,4-piperidine, ligands that bind with high affinity to σ- and phencyclidine receptors, respectively, was detected in all organisms examined. The order of potencies of various ligands to inhibit 1 nM [3H]haloperidol binding in brains of frogs and guinea pigs or 1 nM [3H]N-[1-(2-thienyl)cyclohexyl]-3,4–piperidine in chicken or guinea pig brain homogenates was very similar. However, the characteristics and stereospecificity of binding of the two radioligands in sea anemone were different than in higher organisms. The results suggest that σ– and phencyclidine binding sites are evolutionarily old, as the characteristics of the two sites are well preserved over a range of vertebrate phyla.  相似文献   
89.
Vibrio cholerae non‐O1, non‐O139 (VC_NAG) organisms are universally present in the aquatic environment and regarded as non‐pathogenic bacteria. However, considering that they do occasionally induce gastroenteritis, a study of their virulence and antibiotic resistance genes is important. The presence of enteropathogenic genes, including ctxA, VC_NAG‐specific heat‐stable toxin gene (st), hemolysin (hly), and zona occludens toxin (zot) was determined by PCR in 100 VC_NAG strains isolated in southern Vietnam in 2010–2013 from 94 environmental and six human origins. These 100 VC_NAG strains were also tested phenotypically and genotypically for the presence of the New Delhi metallo‐β‐lactamase (NDM‐1). Of the 100 VC_NAG strains tested, six were positive for ctxA; five from the environment and one of human origin. The st gene was detected in 17 isolates, 15 and two of which were of environmental and human origins, respectively. Gene hly was detected in 19 VC_NAG strains examined, two of which were isolated from humans and 17 from environments. The zot gene was not detected in any of the strains tested. Three VC_NAG strains of environmental origin were confirmed to produce NDM‐1 and the blaNDM‐1 gene was detected in those strains by PCR. Of note, one of the three NDM‐1‐producing VC_NAG strains was confirmed to carry ctxA, st and hly genes concurrently. This is the first report of isolation of NDM‐1‐producing VC_NAG strains in Vietnam.  相似文献   
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