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991.
Veronica Langenes Helena Svensson Lars Börjesson Bengt Gustavsson Mats Bemark Åsa Sjöling Marianne Quiding-Järbrink 《Cancer immunology, immunotherapy : CII》2013,62(11):1687-1695
Recruitment of immune cells to tumors is a complex process crucial for both inflammation-driven tumor progression and specific anti-tumor cytotoxicity. Chemokines control the directed migration of immune cells, and their actions are partly controlled by nonsignaling chemokine decoy receptors. The role of the receptors such as D6, Duffy antigen receptor for chemokines and ChemoCentryx chemokine receptor in immunity to tumors is still unclear. Using real-time PCR, we detected significantly decreased expression of D6 mRNA in colon tumors compared to unaffected mucosa. D6 protein was expressed by lymphatic endothelium and mononuclear cells in the colon lamina propria and detected by immunohistochemistry in two out of six tissue samples containing high D6 mRNA levels, whereas no staining was observed in any tissue samples expressing low mRNA levels. When examining the density of lymphatic vessels in colon tumors, we detected a marked increase in vessels identified by the lymphatic endothelial marker Lyve-1, excluding passive regulation of D6 due to decreased lymphatic vessel density. In parallel, the Treg-recruiting chemokine CCL22, which is sequestered by D6, was threefold increased in tumor tissue. Furthermore, we could show that low D6 expression correlated to more invasive tumors and that tumor location influences D6 expression, which is lower in the more distal parts of the colon. The data support that regulation of D6 by colon tumors results in altered levels of proinflammatory CC chemokines, thereby shaping the local chemokine network to favor tumor survival. This may have implications for the design of future immunotherapy for colon cancer. 相似文献
992.
Michael Ingre Göran Kecklund Torbjörn Åkerstedt Marie Söderström Lena Kecklund 《Chronobiology international》2013,30(2-3):349-358
Forty‐six male train drivers (mean age=46.5, SD=5.1) were recruited to participate in a diary study for 14 consecutive days with questions about their sleep and working hours. A polynomial mixed‐effect regression model showed a curvilinear relation (p <. 001) between shift‐start time and sleep duration for shifts starting at 03∶00–12∶00 h and with a near linear increase for ones starting between 04∶30 and 09∶00 h of approximately 0.7 h for every 1 h the shift was delayed. The longest sleeps were estimated at ~8 h before shifts that started at ~10∶00 h. The shortest sleeps were found for shifts that started before 04∶30 h and were estimated at ~5 h. Individual differences were estimated with a random-effect standard deviation of 0.51 h, independent of shift‐start time (p =.005). One‐half of the between‐subject variance was explained by subjective health. A one‐step decrease in health was associated with a 26 min increase in sleep length. The results have practical implications for constructing shift schedules. Early morning shifts reduced sleep length substantially and should be mixed with later start hours to avoid the accumulation of sleep dept. Delaying the shift‐start past 10∶00 h had little effect on sleep opportunity; however, delaying shift‐start to between 04∶30 and 9∶00 h had a strong impact on sleep length, with 70% of the extra time used for sleep, suggesting large positive effects for this range of shift‐start times. 相似文献
993.
Peak lists are commonly used in NMR as input data for various software tools such as automatic assignment and structure calculation programs. Inconsistencies of chemical shift referencing among different peak lists or between peak and chemical shift lists can cause severe problems during peak assignment. Here we present a simple and robust tool to achieve self-consistency of the chemical shift referencing among a set of peak lists. The Peakmatch algorithm matches a set of peak lists to a specified reference peak list, neither of which have to be assigned. The chemical shift referencing offset between two peak lists is determined by optimizing an assignment-free match score function using either a complete grid search or downhill simplex optimization. It is shown that peak lists from many different types of spectra can be matched reliably as long as they contain at least two corresponding dimensions. Using a simulated peak list, the Peakmatch algorithm can also be used to obtain the optimal agreement between a chemical shift list and experimental peak lists. Combining these features makes Peakmatch a useful tool that can be applied routinely before automatic assignment or structure calculation in order to obtain an optimized input data set. 相似文献
994.
Elena Schmidt Julia Gath Birgit Habenstein Francesco Ravotti Kathrin Székely Matthias Huber Lena Buchner Anja Böckmann Beat H. Meier Peter Güntert 《Journal of biomolecular NMR》2013,56(3):243-254
Solid-state NMR is an emerging structure determination technique for crystalline and non-crystalline protein assemblies, e.g., amyloids. Resonance assignment constitutes the first and often very time-consuming step to a structure. We present ssFLYA, a generally applicable algorithm for automatic assignment of protein solid-state NMR spectra. Application to microcrystals of ubiquitin and the Ure2 prion C-terminal domain, as well as amyloids of HET-s(218–289) and α-synuclein yielded 88–97 % correctness for the backbone and side-chain assignments that are classified as self-consistent by the algorithm, and 77–90 % correctness if also assignments classified as tentative by the algorithm are included. 相似文献
995.
Bruce Erickson Senthamil Paramadayalan Selvan Kerry W.S. Ko Karen Kelly Ariel D. Quiroga Lena Li Randy Nelson Kirst King-Jones René L. Jacobs Richard Lehner 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(6):1113-1123
Hepatic triacylglycerol levels are governed through synthesis, degradation and export of this lipid. Here we demonstrate that enforced expression of hepatic lipase in the endoplasmic reticulum in McArdle RH7777 hepatocytes resulted in a significant decrease in the incorporation of fatty acids into cellular triacylglycerol and cholesteryl ester accompanied by attenuation of secretion of apolipoprotein B-containing lipoproteins. Hepatic lipase-mediated depletion of intracellular lipid storage increased the expression of peroxisome proliferator-activated receptor α and its target genes and augmented oxidation of fatty acids. These data show that 1) hepatic lipase is active in the endoplasmic reticulum and 2) intracellular hepatic lipase modulates cellular lipid metabolism and lipoprotein secretion. 相似文献
996.
Anna-Karin Larsson-Callerfelt Oskar Hallgren Annika Andersson-Sj?land Lena Thiman Johan Bj?rklund Josefine Kron Kristian Nihlberg Leif Bjermer Claes-G?ran L?fdahl Gunilla Westergren-Thorsson 《Respiratory research》2013,14(1):21
Background
Prostacyclin analogs are potent vasodilators and possess anti-inflammatory properties. However, the effect of prostacyclin on extracellular matrix (ECM) in COPD is not well known. Collagen fibrils and proteoglycans are essential ECM components in the lung and fibroblasts are key players in regulating the homeostasis of ECM proteins. The aim was to study the synthesis of prostacyclin and its effect on fibroblast activity and ECM production, and in particular collagen I and the collagen-associated proteoglycans biglycan and decorin.Methods
Parenchymal lung fibroblasts were isolated from lungs from COPD patients (GOLD stage IV) and from lungs and transbronchial biopsies from control subjects. The prostacyclin analog iloprost was used to study the effect of prostacyclin on ECM protein synthesis, migration, proliferation and contractile capacity of fibroblasts.Results
TGF-β1 stimulation significantly increased prostacyclin synthesis in fibroblasts from COPD patients (p < 0.01), but showed no effect on fibroblasts from control subjects. Collagen I synthesis was decreased by iloprost in both control and COPD fibroblasts (p < 0.05). Conversely, iloprost significantly altered biglycan and decorin synthesis in control fibroblasts, but iloprost displayed no effect on these proteoglycans in COPD fibroblasts. Proliferation rate was reduced (p < 0.05) and contractile capacity was increased in COPD fibroblasts (p < 0.05) compared to control fibroblasts. Iloprost decreased proliferative rate in control fibroblasts (p < 0.05), whereas iloprost attenuated contraction capacity in both COPD (p < 0.01) and control fibroblasts (p < 0.05).Conclusions
Iloprost reduced collagen I synthesis and fibroblast contractility but did not affect the collagen-associated proteoglycans or proliferation rate in fibroblasts from COPD patients. Enhanced prostacyclin production could lead to improper collagen network fibrillogenesis and a more emphysematous lung structure in severe COPD patients. 相似文献997.
This circumpolar dataset of the comatulid (Echinodermata: Crinoidea) Promachocrinus kerguelensis (Carpenter, 1888) from the Southern Ocean, documents biodiversity associated with the specimens sequenced in Hemery et al. (2012). The aim of Hemery et al. (2012) paper was to use phylogeographic and phylogenetic tools to assess the genetic diversity, demographic history and evolutionary relationships of this very common and abundant comatulid, in the context of the glacial history of the Antarctic and Sub-Antarctic shelves (Thatje et al. 2005, 2008). Over one thousand three hundred specimens (1307) used in this study were collected during seventeen cruises from 1996 to 2010, in eight regions of the Southern Ocean: Kerguelen Plateau, Davis Sea, Dumont d’Urville Sea, Ross Sea, Amundsen Sea, West Antarctic Peninsula, East Weddell Sea and Scotia Arc including the tip of the Antarctic Peninsula and the Bransfield Strait. We give here the metadata of this dataset, which lists sampling sources (cruise ID, ship name, sampling date, sampling gear), sampling sites (station, geographic coordinates, depth) and genetic data (phylogroup, haplotype, sequence ID) for each of the 1307 specimens. The identification of the specimens was controlled by an expert taxonomist specialist of crinoids (Marc Eléaume, Muséum national d’Histoire naturelle, Paris) and all the COI sequences were matched against those available on the Barcode of Life Data System (BOLD: http://www.boldsystems.org/index.php/IDS_OpenIdEngine). This dataset can be used by studies dealing with, among other interests, Antarctic and/or crinoid diversity (species richness, distribution patterns), biogeography or habitat / ecological niche modeling. This dataset is accessible through the GBIF network at http://ipt.biodiversity.aq/resource.do?r=proke. 相似文献
998.
Forsman A Karlsson M Wennersten L Johansson J Karpestam E 《Evolution; international journal of organic evolution》2011,65(9):2530-2540
Evolutionary theory predicts an interactive process whereby spatiotemporal environmental heterogeneity will maintain genetic variation, while genetic and phenotypic diversity will buffer populations against stress and allow for fast adaptive evolution in rapidly changing environments. Here, we study color polymorphism patterns in pygmy grasshoppers (Tetrix subulata) and show that the frequency of the melanistic (black) color variant was higher in areas that had been ravaged by fires the previous year than in nonburned habitats, that, in burned areas, the frequency of melanistic grasshoppers dropped from ca. 50% one year after a fire to 30% after four years, and that the variation in frequencies of melanistic individuals among and within populations was genetically based on and represented evolutionary modifications. Dark coloration may confer a selective benefit mediated by enhanced camouflage in recently fire-ravaged areas characterized by blackened visual backgrounds before vegetation has recovered. These findings provide rare evidence for unusually large, extremely rapid adaptive contemporary evolution in replicated natural populations in response to divergent and fluctuating selection associated with spatiotemporal environmental changes. 相似文献
999.
The PTPN22 locus is one of the strongest risk factors outside of the major histocompatability complex that associates with autoimmune diseases. PTPN22 encodes lymphoid protein tyrosine phosphatase (Lyp) which is expressed exclusively in immune cells. A single base change in the coding region of this gene resulting in an arginine to tryptophan amino acid substitution within a polyproline binding motif associates with type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosis, Hashimotos thyroiditis, Graves disease, Addison's disease, Myasthenia Gravis, vitiligo, systemic sclerosis juvenile idiopathic arthritis and psoriatic arthritis. Here, we review the current understanding of the PTPN22 locus from a genetic, geographical, biochemical and functional perspective. 相似文献
1000.
The ability to improve fitness via adaptive evolution may be affected by environmental change. We tested this hypothesis in
an in vitro experiment with the plant pathogen Rhizoctonia solani Anastomosis Group 3 (AG-3), assessing genetic and environmental variances under two temperatures (optimal and higher than
optimal) and three fungicide concentrations (no fungicide, low and high concentration of a copper-based fungicide). We measured
the mean daily growth rate, the coefficient of variation for genotypic (I
G) and environmental variance (I
E) in growth, and broad-sense heritability in growth. Both higher temperature and increased fungicide concentration caused
a decline in growth, confirming their potential as stressors for the pathogen. All types of standardized variances in growth—I
G, phenotypic variance, and I
E as a trend—increased with elevated stress. However, heritability was not significantly higher under enhanced stress because
the increase in I
G was counterbalanced by somewhat increased I
E. The results illustrate that predictions for adaptation under environmental stress may depend on the type of short-term evolvability
measure. Because mycelial growth is linked to fitness, I
G reflects short-term evolvability better than heritability, and it indicates that the evolutionary potential of R. solani is positively affected by stress. 相似文献