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21.
J.H. Boergermann J. Kopf P.B. Yu P. Knaus 《The international journal of biochemistry & cell biology》2010,42(11):1802-1807
Bone morphogenetic proteins (BMPs) are key regulators of cell fate decisions during embryogenesis and tissue homeostasis. BMPs signal through a coordinated assembly of two types of transmembrane serine/threonine kinase receptors to induce Smad1/5/8 plus non-Smad pathways, such as MAPK and Akt. The recent discovery of BMP receptor inhibitors opened new avenues to study specific BMP signalling and to delineate this effect from TGF-β and Activin signalling. Here we present comprehensive and quantitative analyses on both canonical and non-Smad mediated BMP signalling under Dorsomorphin (DM) and LDN-193189 (LDN) treatment conditions. We demonstrate for the first time, that both compounds affect not only the Smad but also the non-Smad signalling pathways induced by either BMP2, BMP6 or GDF5. The activation of p38, ERK1/2 and Akt in C2C12 cells was inhibited by DM and LDN. In addition “off-target” effects on all branches of BMP non-Smad signalling are presented. From this we conclude that the inhibition of BMP receptors by DM and more efficiently by LDN-193189 affects all known BMP induced signalling cascades. 相似文献
22.
Jegerlehner A Maurer P Bessa J Hinton HJ Kopf M Bachmann MF 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(4):2415-2420
Although IgG2a is the most potent Ab isotype in the host response to viral and bacterial infections, the regulation of class switch recombination to IgG2a in vivo is not yet well understood. Recognition of pathogen-associated molecular patterns by dendritic cells expressing TLRs, like TLR7, recognizing ssRNA, or TLR9, recognizing DNA rich in nonmethylated CG motifs (CpG), favors induction of Th1 responses. It is generally assumed that these Th1 responses are responsible for the TLR-mediated induction of IgG2a. Using virus-like particles loaded with CpGs, we show here that TLR9 ligands can directly stimulate B cells to undergo isotype switching to IgG2a. Unexpectedly, TLR9 expression in non-B cells did not affect isotype switching in the Ab response against virus-like particles. Thus, TLR9 can regulate isotype switching to IgG2a directly by interacting with B cells rather than indirectly by inducing Th1 responses. 相似文献
23.
Cancer is a result of complex changes that occur in normal cells as they transform to become malignant and further when they become metastatic. These changes are not a consequence of a single protein but rather involve multiple proteins that function in pathways and networks. Thus, profiling cancer-associated changes requires simultaneous measurement of many proteins in a single sample. Identifying these changes may lead to the discovery of cancer-associated biomarkers that may assist in diagnosis, prognosis, patient monitoring and possibly for therapeutic purposes. Antibody arrays are a relatively new technology that enables one to perform multiplex high-throughput protein expression profiling. This review describes current technologies in antibody array and assay design, and presents a survey of the current literature on the use of these arrays in cancer research. 相似文献
24.
The availability of sequenced genomes of human and many experimental animals necessitated the development of new technologies and powerful computational tools that are capable of exploiting these genomic data and ask intriguing questions about complex nature of biological processes. This gave impetus for developing whole genome approaches that can produce functional information of genes in the form of expression profiles and unscramble the relationships between variation in gene expression and the resulting physiological outcome. These profiles represent genetic fingerprints or catalogue of genes that characterize the cell or tissue being studied and provide a basis from which to begin an investigation of the underlying biology. Among the most powerful and versatile tools are high-density DNA microarrays to analyze the expression patterns of large numbers of genes across different tissues or within the same tissue under a variety of experimental conditions or even between species. The wide spread use of microarray technologies is generating large sets of data that is stimulating the development of better analytical tools so that functions can be predicted for novel genes. In this review, the authors discuss how these profiles are being used at various stages of the drug discovery process and help in the identification of new drug targets, predict the function of novel genes, and understand individual variability in response to drugs. 相似文献
25.
CA Kalva-Filho EZ Campos VL Andrade ASR Silva AM Zagatto MCS Lima M Papoti 《Biology of sport / Institute of Sport》2015,32(4):333-337
The aims of the present study were to investigate the relationship of aerobic and anaerobic parameters with 400 m performance, and establish which variable better explains long distance performance in swimming. Twenty-two swimmers (19.1±1.5 years, height 173.9±10.0 cm, body mass 71.2±10.2 kg; 76.6±5.3% of 400 m world record) underwent a lactate minimum test to determine lactate minimum speed (LMS) (i.e., aerobic capacity index). Moreover, the swimmers performed a 400 m maximal effort to determine mean speed (S400m), peak oxygen uptake () and total anaerobic contribution (CANA). The CANA was assumed as the sum of alactic and lactic contributions. Physiological parameters of 400 m were determined using the backward extrapolation technique ( and alactic contributions of CANA) and blood lactate concentration analysis (lactic anaerobic contributions of CANA). The Pearson correlation test and backward multiple regression analysis were used to verify the possible correlations between the physiological indices (predictor factors) and S400m (independent variable) (p < 0.05). Values are presented as mean ± standard deviation. Significant correlations were observed between S400m (1.4±0.1 m·s-1) and LMS (1.3±0.1 m·s-1; r = 0.80), (4.5±3.9 L·min-1; r = 0.72) and CANA (4.7±1.5 L·O2; r= 0.44). The best model constructed using multiple regression analysis demonstrated that LMS and explained 85% of the 400 m performance variance. When backward multiple regression analysis was performed, CANA lost significance. Thus, the results demonstrated that both aerobic parameters (capacity and power) can be used to predict 400 m swimming performance. 相似文献
26.
Konrad Zych Yang Li Joeri K van der Velde Ronny VL Joosen Wilco Ligterink Ritsert C Jansen Danny Arends 《BMC bioinformatics》2015,16(1)
Background
Genetic markers and maps are instrumental in quantitative trait locus (QTL) mapping in segregating populations. The resolution of QTL localization depends on the number of informative recombinations in the population and how well they are tagged by markers. Larger populations and denser marker maps are better for detecting and locating QTLs. Marker maps that are initially too sparse can be saturated or derived de novo from high-throughput omics data, (e.g. gene expression, protein or metabolite abundance). If these molecular phenotypes are affected by genetic variation due to a major QTL they will show a clear multimodal distribution. Using this information, phenotypes can be converted into genetic markers.Results
The Pheno2Geno tool uses mixture modeling to select phenotypes and transform them into genetic markers suitable for construction and/or saturation of a genetic map. Pheno2Geno excludes candidate genetic markers that show evidence for multiple possibly epistatically interacting QTL and/or interaction with the environment, in order to provide a set of robust markers for follow-up QTL mapping.We demonstrate the use of Pheno2Geno on gene expression data of 370,000 probes in 148 A. thaliana recombinant inbred lines. Pheno2Geno is able to saturate the existing genetic map, decreasing the average distance between markers from 7.1 cM to 0.89 cM, close to the theoretical limit of 0.68 cM (with 148 individuals we expect a recombination every 100/148=0.68 cM); this pinpointed almost all of the informative recombinations in the population.Conclusion
The Pheno2Geno package makes use of genome-wide molecular profiling and provides a tool for high-throughput de novo map construction and saturation of existing genetic maps. Processing of the showcase dataset takes less than 30 minutes on an average desktop PC. Pheno2Geno improves QTL mapping results at no additional laboratory cost and with minimum computational effort. Its results are formatted for direct use in R/qtl, the leading R package for QTL studies. Pheno2Geno is freely available on CRAN under “GNU GPL v3”. The Pheno2Geno package as well as the tutorial can also be found at: http://pheno2geno.nl.Electronic supplementary material
The online version of this article (doi:10.1186/s12859-015-0475-6) contains supplementary material, which is available to authorized users. 相似文献27.
Acetonation of dimeric 1,6-anhydro-β-D-arabino-hexopyranos-3-ulose yields, besides a monomeric di-O-isopropylidene compound, the dimer 2, which crystallizes in space group P212121 with a 1.3680 (9), b 1.0686 (7), and c 1.0319 (7) nm, Z 4. The crystal and molecular structure of 2 have been determined by X-ray analysis with direct methods and was refined to a final Rw of 5.55% for 2468 reflections. Compound 2 has not the same dimeric structure as the parent compound with a central 1,4-dioxane ring, but contains instead a central 1,3-dioxolane ring. The pyranose ring bearing the isopropylidene group adopts an almost ideal sofa conformation, with a nearly planar arrangement of C-1, C-2, C-3, C-4, and C-5. By analogy, it was concluded that the dimeric mono-O-isopropylidene derivative 7 of 1,6-anhydro-β-D-xylo-hexopyranos-3-ulose has the same asymmetric structure. The 360-MHz 1H-n.m.r. spectra of both compounds are in full agreement with the proposed structures. 相似文献
28.
Interleukin-1 is responsible for acute lung immunopathology but increases survival of respiratory influenza virus infection 总被引:8,自引:0,他引:8 下载免费PDF全文
Interleukin-1alpha (IL-1alpha) and IL-1beta are proinflammatory cytokines, which induce a plethora of genes and activities by binding to the type 1 IL-1 receptor (IL-1R1). We have investigated the role of IL-1 during pulmonary antiviral immune responses in IL-1R1(-/-) mice infected with influenza virus. IL-1R1(-/-) mice showed markedly reduced inflammatory pathology in the lung, primarily due to impaired neutrophil recruitment. Activation of CD4(+) T cells in secondary lymphoid organs and subsequent migration to the lung were impaired in the absence of IL-1R1. In contrast, activation of virus-specific cytotoxic T lymphocytes and killing of virus-infected cells in the lung were intact. Influenza virus-specific immunoglobulin G (IgG) and IgA antibody responses were intact, while the IgM response was markedly reduced in both serum and mucosal sites in IL-1R1(-/-) mice. We found significantly increased mortality in the absence of IL-1R1; however, lung viral titers were only moderately increased. Our results demonstrate that IL-1alpha/beta mediate acute pulmonary inflammatory pathology while enhancing survival during influenza virus infection. IL-1alpha/beta appear not to influence killing of virus-infected cells but to enhance IgM antibody responses and recruitment of CD4(+) T cells to the site of infection. 相似文献
29.
Abel B Freigang S Bachmann MF Boschert U Kopf M 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(9):6006-6013
Osteopontin (OPN) has been defined as a key cytokine promoting the release of IL-12 and hence inducing the development of protective cell-mediated immunity to viruses and intracellular pathogens. To further characterize the role of OPN in antiviral immunity, OPN-deficient (OPN-/-) mice were analyzed after infection with influenza virus and vaccinia virus. Surprisingly, we found that viral clearance, lung inflammation, and recruitment of effector T cells to the lung were unaffected in OPN-/- mice after influenza infection. Furthermore, effector status of T cells was normal as demonstrated by normal IFN-gamma production and CTL lytic activity. Moreover, activation and Th1 differentiation of naive TCR transgenic CD4+ T cells by dendritic cells and cognate Ag was normal in the absence of OPN in vitro. Contrary to a previous report, we found that OPN-/- mice mounted a normal immune response to Listeria monocytogenes. In conclusion, OPN is dispensable for antiviral immune responses against influenza virus and vaccinia virus. 相似文献
30.
This study presents the first histology‐based assessment of the reproductive dynamics of south‐west Pacific striped marlin Kajikia audax. Maturity and reproductive status were assessed from histological sections of ovaries (n = 234) and testes (n = 243) of fish caught in commercial longline and recreational fisheries between 2006 and 2009. Spawning peaked in the Coral Sea during November and December at sea surface temperatures between 24·8 and 28·3° C. Lower jaw fork length (LLJF) at 50% maturity (LLJF50), a key variable for stock assessment, was estimated to be 2100 ± 102 mm (mean + s.e .) for females and 1668 ± 18 mm for males. Unlike large pelagic tunas Thunnus spp., the proportion of females increased with length and spawning fish formed multiple large‐scale aggregations within a broad latitudinal band. This study provides a starting point for biological parameters needed for stock assessment and conservation of K. audax and introduces the multiple aggregation spawning concept as a reproductive mechanism to explain genetic heterogeneity observed in some highly migratory species. 相似文献