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991.
Antonelli A Ferrari SM Frascerra S Galetta F Franzoni F Corrado A Miccoli M Benvenga S Paolicchi A Ferrannini E Fallahi P 《Cytokine》2011,55(2):288-293
Chemokine (CXC motif) ligand (CXCL)9 (CXCL9) has been shown to be involved in autoimmune thyroid disorders, however no data are present about CXCL9 circulating levels in chronic autoimmune thyroiditis (AT) vs controls. Serum CXCL9 (and for comparison CXCL10) has been measured in patients with AT vs normal control and nontoxic multinodular goiter, and this parameter has been related to the clinical phenotype. For this study we selected 189 consecutive patients with newly diagnosed AT, 63 euthyroid controls, 30 patients with nontoxic multinodular goiter. The three groups were similar in gender distribution and age; 26% of AT patients had subclinical hypothyroidism. Serum CXCL9 was significantly higher in AT (148±110 pg/mL) than in controls (71±34 pg/mL) or patients with multinodular goiter (87±35 pg/mL) (p<0.0001). Among AT patients, CXCL9 levels were significantly higher in patients older than 50 years, those with a hypoechoic ultrasonographic pattern or with hypothyroidism. Also CXCL10 was confirmed to be associated with AT, overall in presence of hypothyroidism. In a multiple linear regression model of CXCL9 (ln[pg/mL]) vs age, thyroid volume, TSH, AbTg, AbTPO, hypoechoic pattern, the presence of hypervascularity, and CXCL10 (ln[pg/mL]), only TSH and CXCL10 (ln[pg/mL]) were significantly related to serum CXCL9 levels. We show that circulating CXCL9 is increased in patients with aggressive thyroiditis and hypothyroidism. A strong relation between circulating CXCL9 and CXCL10 has been first shown, underlining the importance of a T helper 1 immune attack in the initiation of AT. 相似文献
992.
Figueroa M González-Andrade M Sosa-Peinado A Madariaga-Mazón A Del Río-Portilla F González Mdel C Mata R 《Journal of enzyme inhibition and medicinal chemistry》2011,26(3):378-385
A new malbrancheamide analogue, isomalbrancheamide B (3), along with three known compounds, malbrancheamide (1), isomalbrancheamide (2), and premalbrancheamide (4), were isolated in higher yields from the alkaloid fraction of the fungus Malbranchea aurantiaca. The interaction of the alkaloids 1-4 with calmodulin (CaM) was analyzed using different enzymatic, fluorescence, spectroscopic, nuclear magnetic resonance (NMR), and molecular modelling techniques. On the basis of the enzymatic and fluorescence experiments, malbrancheamides 1-3 are classical CaM inhibitors. Compound 4, however, did not quench the extrinsic fluorescence of the CaM biosensor indicating that it could be a functional inhibitor. Circular dichroism, NMR, and molecular modelling studies revealed that 1 binds to CaM in the same hydrophobic pocket than the chlorpromazine and trifluoperazine, two classical CaM inhibitors. Thus, malbrancheamide and related monochlorinated analogues are compounds with a high potential for the development of new therapeutic agents, involving CaM as their molecular target. 相似文献
993.
Thomas Unterthiner Anne-Kathrin Schultz Jan Bulla Burkhard Morgenstern Mario Stanke Ingo Bulla 《BMC bioinformatics》2011,12(1):93
Background
Methods of determining whether or not any particular HIV-1 sequence stems - completely or in part - from some unknown HIV-1 subtype are important for the design of vaccines and molecular detection systems, as well as for epidemiological monitoring. Nevertheless, a single algorithm only, the Branching Index (BI), has been developed for this task so far. Moving along the genome of a query sequence in a sliding window, the BI computes a ratio quantifying how closely the query sequence clusters with a subtype clade. In its current version, however, the BI does not provide predicted boundaries of unknown fragments. 相似文献994.
Mario?MenschikowskiEmail author Albert?Hagelgans Oliver?Tiebel Ludwig?Klinsmann Graeme?Eisenhofer Gabriele?Siegert 《Cancer cell international》2011,11(1):4
Background
Increasing evidences show that beyond its role in coagulation, endothelial protein C receptor (EPCR) interferes with carcinogenesis. Pro-carcinogenic effects of EPCR were linked with a raised generation of activated protein C (aPC) and anti-apoptotic signalling. This study was carried out to analyze the expression, cell surface exposition, and shedding of EPCR in normal and malignant prostate cell lines. 相似文献995.
Pivac N Knezević A Gornik O Pucić M Igl W Peeters H Crepel A Steyaert J Novokmet M Redzić I Nikolac M Hercigonja VN Curković KD Curković M Nedić G Muck-Seler D Borovecki F Rudan I Lauc G 《Molecular & cellular proteomics : MCP》2011,10(1):M110.004200
Over a half of all proteins are glycosylated, and their proper glycosylation is essential for normal function. Unfortunately, because of structural complexity of nonlinear branched glycans and the absence of genetic template for their synthesis, the knowledge about glycans is lagging significantly behind the knowledge about proteins or DNA. Using a recently developed quantitative high throughput glycan analysis method we quantified components of the plasma N-glycome in 99 children with attention-deficit hyperactivity disorder (ADHD), 81 child and 5 adults with autism spectrum disorder, and a total of 340 matching healthy controls. No changes in plasma glycome were found to associate with autism spectrum disorder, but several highly significant associations were observed with ADHD. Further structural analysis of plasma glycans revealed that ADHD is associated with increased antennary fucosylation of biantennary glycans and decreased levels of some complex glycans with three or four antennas. The design of this study prevented any functional conclusions about the observed associations, but specific differences in glycosylation appears to be strongly associated with ADHD and warrants further studies in this direction. 相似文献
996.
997.
A reversible form of axon damage in experimental autoimmune encephalomyelitis and multiple sclerosis
Nikić I Merkler D Sorbara C Brinkoetter M Kreutzfeldt M Bareyre FM Brück W Bishop D Misgeld T Kerschensteiner M 《Nature medicine》2011,17(4):495-499
In multiple sclerosis, a common inflammatory disease of the central nervous system, immune-mediated axon damage is responsible for permanent neurological deficits. How axon damage is initiated is not known. Here we use in vivo imaging to identify a previously undescribed variant of axon damage in a mouse model of multiple sclerosis. This process, termed 'focal axonal degeneration' (FAD), is characterized by sequential stages, beginning with focal swellings and progressing to axon fragmentation. Notably, most swollen axons persist unchanged for several days, and some recover spontaneously. Early stages of FAD can be observed in axons with intact myelin sheaths. Thus, contrary to the classical view, demyelination-a hallmark of multiple sclerosis-is not a prerequisite for axon damage. Instead, focal intra-axonal mitochondrial pathology is the earliest ultrastructural sign of damage, and it precedes changes in axon morphology. Molecular imaging and pharmacological experiments show that macrophage-derived reactive oxygen and nitrogen species (ROS and RNS) can trigger mitochondrial pathology and initiate FAD. Indeed, neutralization of ROS and RNS rescues axons that have already entered the degenerative process. Finally, axonal changes consistent with FAD can be detected in acute human multiple sclerosis lesions. In summary, our data suggest that inflammatory axon damage might be spontaneously reversible and thus a potential target for therapy. 相似文献
998.
999.
1000.
Quaglio E Restelli E Garofoli A Dossena S De Luigi A Tagliavacca L Imperiale D Migheli A Salmona M Sitia R Forloni G Chiesa R 《PloS one》2011,6(4):e19339
The cellular pathways activated by mutant prion protein (PrP) in genetic prion diseases, ultimately leading to neuronal dysfunction and degeneration, are not known. Several mutant PrPs misfold in the early secretory pathway and reside longer in the endoplasmic reticulum (ER) possibly stimulating ER stress-related pathogenic mechanisms. To investigate whether mutant PrP induced maladaptive responses, we checked key elements of the unfolded protein response (UPR) in transgenic mice, primary neurons and transfected cells expressing two different mutant PrPs. Because ER stress favors the formation of untranslocated PrP that might aggregate in the cytosol and impair proteasome function, we also measured the activity of the ubiquitin proteasome system (UPS). Molecular, biochemical and immunohistochemical analyses found no increase in the expression of UPR-regulated genes, such as Grp78/Bip, CHOP/GADD153, or ER stress-dependent splicing of the mRNA encoding the X-box-binding protein 1. No alterations in UPS activity were detected in mutant mouse brains and primary neurons using the Ub(G76V)-GFP reporter and a new fluorogenic peptide for monitoring proteasomal proteolytic activity in vivo. Finally, there was no loss of proteasome function in neurons in which endogenous PrP was forced to accumulate in the cytosol by inhibiting cotranslational translocation. These results indicate that neither ER stress, nor perturbation of proteasome activity plays a major pathogenic role in prion diseases. 相似文献