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91.
Hendrik-Jan Megens Richard PMA Crooijmans John WM Bastiaansen Hindrik HD Kerstens Albart Coster Ruud Jalving Addie Vereijken Pradeepa Silva William M Muir Hans H Cheng Olivier Hanotte Martien AM Groenen 《BMC genetics》2009,10(1):1-11
Background
Toll like receptors (TLR) play the central role in the recognition of pathogen associated molecular patterns (PAMPs). Mutations in the TLR1, TLR2 and TLR4 genes may change the ability to recognize PAMPs and cause altered responsiveness to the bacterial pathogens.Results
The study presents association between TLR gene mutations and increased susceptibility to Mycobacterium avium subsp. paratuberculosis (MAP) infection. Novel mutations in TLR genes (TLR1- Ser150Gly and Val220Met; TLR2 – Phe670Leu) were statistically correlated with the hindrance in recognition of MAP legends. This correlation was confirmed subsequently by measuring the expression levels of cytokines (IL-4, IL-8, IL-10, IL-12 and IFN-γ) in the mutant and wild type moDCs (mocyte derived dendritic cells) after challenge with MAP cell lysate or LPS. Further in silico analysis of the TLR1 and TLR4 ectodomains (ECD) revealed the polymorphic nature of the central ECD and irregularities in the central LRR (leucine rich repeat) motifs.Conclusion
The most critical positions that may alter the pathogen recognition ability of TLR were: the 9th amino acid position in LRR motif (TLR1–LRR10) and 4th residue downstream to LRR domain (exta-LRR region of TLR4). The study describes novel mutations in the TLRs and presents their association with the MAP infection. 相似文献92.
Ruud ter Haar Henk A. Schols Lambertus A.M. van den Broek Dilek Sağlam August E. Frissen Carmen G. Boeriu Harry Gruppen 《Journal of Molecular Catalysis .B, Enzymatic》2010,62(2):183-189
The cause of discrepancies in the literature regarding the specificity of immobilized Candida antarctica lipase B in the acylation of oligosaccharides was examined. Molecular sieves, generally used to control the water content during acylation reactions, turned out to have an important role in this. It was proven that molecular sieves alone can catalyze the acylation of fructose oligomers using vinyl laurate, leading to multiple substitution of the oligomers. This effect was the most profound at conditions unfavorable for the enzyme, because this resulted in a relatively high concentration of the chemically produced adducts. The enzyme alone catalyzed the formation of monosubstituted oligomers. It was proven that even solvent pre-drying by molecular sieves already causes the release of catalyzing compounds to the liquid, leading to subsequent catalysis. These findings should be taken into account when applying molecular sieves in this type of reactions in the future. Molecular sieves could, moreover, be used as a catalyst when multiple substitution is desired. 相似文献
93.
Exley R Moroni M Sasdelli F Houlihan LM Lukas RJ Sher E Zwart R Bermudez I 《Journal of neurochemistry》2006,98(3):876-885
Alpha4 and beta2 nicotinic acetylcholine (nACh) receptor subunits expressed heterologously in Xenopus oocytes assemble into a mixture of receptors with high and low agonist sensitivity whose relative abundance is influenced by the heteropentamer subunit ratio. We have found that inhibition of protein kinase A by KT5720 decreased maximal [3H]cytisine binding and acetylcholine (ACh)-induced current responses, and increased the relative proportion of alpha4beta2 receptors with high agonist sensitivity. Mutation of serine 467, a putative protein kinase A substrate in a chaperone protein binding motif within the large cytoplasmic domain of the alpha4 subunit, to alanine or asparate decreased or increased, respectively, maximal [3H]cytisine binding and ACh response amplitude. Expression of alpha4S467A mutant subunits decreased steady levels of alpha4 and the relative proportion of alpha4beta2 receptors with low agonist sensitivity, whilst expression of alpha4S467D increased steady levels of alpha4 and alpha4beta2 receptors with low agonist sensitivity. Difopein, an inhibitor of chaperone 14-3-3 proteins, decreased [3H]cytisine binding and ACh responses and increased the proportion of alpha4beta2 with high sensitivity to activation by ACh. Thus, post-translational modification affecting steady-state levels of alpha4 subunits provides a possible means for physiologically relevant, chaperone-mediated variation in the relative proportion of high and low agonist sensitivity alpha4beta2 nACh receptors. 相似文献
94.
A Single Oncogenic Enhancer Rearrangement Causes Concomitant EVI1 and GATA2 Deregulation in Leukemia
Stefan Gröschel Mathijs A. Sanders Remco Hoogenboezem Elzo de Wit Britta A.M. Bouwman Claudia Erpelinck Vincent H.J. van der Velden Marije Havermans Roberto Avellino Kirsten van Lom Elwin J. Rombouts Mark van Duin Konstanze Döhner H. Berna Beverloo James E. Bradner Hartmut Döhner Bob Löwenberg Peter J.M. Valk Eric M.J. Bindels Wouter de Laat Ruud Delwel 《Cell》2014
95.
van de Pas NC Woutersen RA van Ommen B Rietjens IM de Graaf AA 《Biochimica et biophysica acta》2011,1811(5):333-342
The LDL cholesterol (LDL-C) and HDL cholesterol (HDL-C) concentrations are determined by the activity of a complex network of reactions in several organs. Physiologically-based kinetic (PBK) computational models can be used to describe these different reactions in an integrated, quantitative manner. A PBK model to predict plasma cholesterol levels in the mouse was developed, validated, and analyzed. Kinetic parameters required for defining the model were obtained using data from published experiments. To construct the model, a set of appropriate submodels was selected from a set of 65,536 submodels differing in the kinetic expressions of the reactions. A submodel was considered appropriate if it had the ability to correctly predict an increased or decreased plasma cholesterol level for a training set of 5 knockout mouse strains. The model thus defined consisted of 8 appropriate submodels and was validated using data from an independent set of 9 knockout mouse strains. The model prediction is the average prediction of 8 appropriate submodels. Remarkably, these submodels had in common that the rate of cholesterol transport from the liver to HDL was not dependent on hepatic cholesterol concentrations. The model appeared able to accurately predict in a quantitative way the plasma cholesterol concentrations of all 14 knockout strains considered, including the frequently used Ldlr-/- and Apoe-/- mouse strains. The model presented is a useful tool to predict the effect of knocking out genes that act in important steps in cholesterol metabolism on total plasma cholesterol, HDL-C and LDL-C in the mouse. 相似文献
96.
Out R Hoekstra M Spijkers JA Kruijt JK van Eck M Bos IS Twisk J Van Berkel TJ 《Journal of lipid research》2004,45(11):2088-2095
Scavenger receptor class B type I (SR-BI) has been identified as a functional HDL binding protein that can mediate the selective uptake of cholesteryl ester (CE) from HDL. To quantify the in vivo role of SR-BI in the process of selective uptake, HDL was labeled with cholesteryl ether ([(3)H] CEt-HDL) and (125)I-tyramine cellobiose ([(125)I]TC-HDL) and injected into SR-BI knockout (KO) and wild-type (WT) mice. In SR-BI KO mice, the clearance of HDL-CE from the blood circulation was greatly diminished (0.043 +/- 0.004 pools/h for SR-BI KO mice vs. 0.106 +/- 0.004 pools/h for WT mice), while liver and adrenal uptake were greatly reduced. Utilization of double-labeled HDL ([(3)H]CEt and [(125)I]TC) indicated the total absence in vivo of the selective decay and liver uptake of CE from HDL in SR-BI KO mice. Parenchymal cells isolated from SR-BI KO mice showed similar association values for [(3)H]CEt and [(125)I]TC in contrast to WT cells, indicating that in parenchymal liver cells SR-BI is the only molecule exerting selective CE uptake from HDL. Thus, in vivo and in vitro, SR-BI is the sole molecule mediating the selective uptake of CE from HDL by the liver and the adrenals, making it the unique target to modulate reverse cholesterol transport. 相似文献
97.
Jim Kaput Ben van Ommen Bas Kremer Corrado Priami Jacqueline Pontes Monteiro Melissa Morine Fre Pepping Zoey Diaz Michael Fenech Yiwu He Ruud Albers Christian A. Drevon Chris T. Evelo Robert E. W. Hancock Carel IJsselmuiden L. H. Lumey Anne-Marie Minihane Michael Muller Chiara Murgia Marijana Radonjic Bruno Sobral Keith P. West Jr. 《Genes & nutrition》2014,9(1)
Nutrition research, like most biomedical disciplines, adopted and often uses experimental approaches based on Beadle and Tatum’s one gene—one polypeptide hypothesis, thereby reducing biological processes to single reactions or pathways. Systems thinking is needed to understand the complexity of health and disease processes requiring measurements of physiological processes, as well as environmental and social factors, which may alter the expression of genetic information. Analysis of physiological processes with omics technologies to assess systems’ responses has only become available over the past decade and remains costly. Studies of environmental and social conditions known to alter health are often not connected to biomedical research. While these facts are widely accepted, developing and conducting comprehensive research programs for health are often beyond financial and human resources of single research groups. We propose a new research program on essential nutrients for optimal underpinning of growth and health (ENOUGH) that will use systems approaches with more comprehensive measurements and biostatistical analysis of the many biological and environmental factors that influence undernutrition. Creating a knowledge base for nutrition and health is a necessary first step toward developing solutions targeted to different populations in diverse social and physical environments for the two billion undernourished people in developed and developing economies. 相似文献
98.
Jip J. C. Ramakers Martijn Dorenbosch Ruud P. B. Foppen 《European Journal of Wildlife Research》2014,60(6):927-931
We studied the effect of a forest edge management quasi-experiment on hazel dormouse (Muscardinus avellanarius) nest numbers in the reproductive season in the Netherlands. We found that the number of nests increased significantly from 2009 to 2013 in managed edges after clearing 75–100 % of mature trees, with a peak in the second year, whereas those in unmanaged edges decreased. In addition, we studied habitat characteristics in forest edges and hedgerows, and found a positive effect of a high upper shrub layer and a high abundance of blackberry (Rubus fruticosus agg. and Rubus spp.), rowan (Sorbus aucuparia) and common hawthorn (Crataegus monogyna) on nest densities. Based on these results, we propose a potential dormouse management strategy that extends conventionally advocated coppice management for regions with well-developed forest edges by (i) postulating a blackberry-oriented landscape restoration approach and (ii) using clearing of mature trees as a tool to boost local dormouse populations in forest edges that have become unsuitable as dormouse habitat due to vegetational succession. 相似文献
99.
Maarten W. Barentsz Hester Wessels Paul J. van Diest Ruud M. Pijnappel Carmen C. van der Pol Arjen J. Witkamp Maurice A. A. J. van den Bosch Helena M. Verkooijen 《PloS one》2014,9(7)
Background
Same-day diagnosis based on histology is increasingly being offered to patients suspected of breast cancer. We evaluated to which extent same-day diagnosis affected diagnostic accuracy and patients'' anxiety levels during the diagnostic phase.Patients and methods
All 759 women referred for same-day evaluation of suspicious breast lesions between November 2011–March 2013 were included. Diagnostic accuracy was assessed by linking all patients to the national pathology database to identify diagnostic discrepancies, in which case slides were reviewed. Patients'' anxiety was measured in 127 patients by the State Trait and Anxiety Inventory on six moments during the diagnostic workup and changes over time (< = 1 week) were analyzed by mixed effect models.Results
Core-needle biopsy was indicated in 374/759 patients (49.3%) and in 205/759 (27%) patients, invasive or in situ cancer was found. Final diagnosis on the same day was provided for 606/759 (79.8%) patients. Overall, 3/759 (0.4%) discordant findings were identified. Anxiety levels decreased significantly over time from 45.2 to 30.0 (P = <0.001). Anxiety levels decreased from 44.4 to 25.9 (P = <0.001) for patients with benign disease, and remained unchanged for patients diagnosed with malignancies (48.6 to 46.7, P = 0.933). Time trends in anxiety were not affected by other patient or disease characteristics like age, education level or (family) history of breast cancer.Conclusion
Same-day histological diagnosis is feasible in the vast majority of patients, without impairing diagnostic accuracy. Patients'' anxiety rapidly decreased in patients with a benign diagnosis and remained constant in patients with malignancy. 相似文献100.
It has been shown that dominant individuals sustain eye-contact when non-consciously confronted with angry faces, suggesting reflexive mechanisms underlying dominance behaviors. However, dominance and submission can be conveyed and provoked by means of not only facial but also bodily features. So far few studies have investigated the interplay of body postures with personality traits and behavior, despite the biological relevance and ecological validity of these postures. Here we investigate whether non-conscious exposure to bodily expressions of anger evokes reflex-like dominance behavior. In an interactive eye-tracking experiment thirty-two participants completed three social dominance tasks with angry, happy and neutral facial, bodily and face and body compound expressions that were masked from consciousness. We confirmed our predictions of slower gaze-aversion from both non-conscious bodily and compound expressions of anger compared to happiness in high dominant individuals. Results from a follow-up experiment suggest that the dominance behavior triggered by exposure to bodily anger occurs with basic detection of the category, but not recognition of the emotional content. Together these results suggest that dominant staring behavior is reflexively driven by non-conscious perception of the emotional content and triggered by not only facial but also bodily expression of anger. 相似文献