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Timidity in dogs is a trait with high heritability. However, the relevant genetic factors and markers associated with this condition are largely unknown. The function of the catechol‐O‐methyl transferase (COMT) gene has been found to be associated with human fearful or anxious emotions, and the COMT:p.Val158Met polymorphism locus is significantly related to anxious behavior. In the present study, the correlation between timidity and four single nucleotide polymorphism (SNP) variations (C.‐1666C>G c.39A>G, c.216G>A, c.482G>A) of the COMT gene was investigated in dogs. The evaluation was based on the dog courage assessment assay and a genotype and haplotype analysis in Labrador Retrievers (LR) and Golden Retrievers (GR). The principal components analysis factor structure of the courage phenotype was invariant between LR and GR. Sex, breed and age had no statistically significant effect on the timidity of the dogs. All SNP loci detected were in Hardy–Weinberg equilibrium. The c.39A>G locus was removed in the subsequent association analysis due to the significant difference between LR and GR in genotype distributions. Intriguingly, the genotypes and haplotypes of the COMT gene were significantly and highly correlated with the timidity of LR and GR. The A alleles of the COMT:c.216G>A and c.482G>A loci appeared to play a dominant role in the timid behavior of the dogs. This result supports and broadens the warrior/worrier hypothesis and will have important implications for the understanding of the evolution of temperament in dogs. Additionally, the results provide predictive genetic markers for temperament in dogs. 相似文献
103.
Embryos of most fish develop externally and are exposed to an aquatic environment full of potential pathogens, whereas they have little or only limited ability to mount an efficient and protective response. How fish embryos survive pathogenic attacks remains poorly defined. Here we demonstrate that the maternal immunization of female zebrafish with formalin-killed Aeromonas hydrophila causes a significant increase in C3 and Bf contents in the mother, a corresponding rise in the offspring, and induces a remarkable increase in the hemolytic activities in both the mother and offspring. In addition, the embryos derived from the immunized mother are significantly more tolerant to A. hydrophila challenge than those from the unimmunized fish, and blocking C3 and Bf activities by injection of the antibodies against C3 and Bf into the embryos render them more susceptible to A. hydrophila. These results clearly show that the protection of zebrafish embryos against A. hydrophila can be achieved by the maternally-transferred immunity of the complement system operating via the alternative pathway. This appears to be the first report providing in vivo evidences for the protective role of the alternative complement components in the early embryos of zebrafish, paving the way for insights into the in vivo function of other maternally-transferred factors in fish. 相似文献
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Mingyue Wang Pranab K Mukherjee Jyotsna Chandra Ali Abdul Lattif Thomas S McCormick Mahmoud A Ghannoum 《BMC microbiology》2008,8(1):31
Background
We have previously shown that supernatant from Candida albicans (CA) culture contains a Secretory Interleukin (IL)-12 Inhibitory Factor (CA-SIIF), which inhibits IL-12 production by human monocytes. However, the effect of CA-SIIF on secretion of other cytokines by monocytes is unknown, and detailed characterization of this factor has not been performed. 相似文献107.
Moist chilling (cold stratification) is well-known as a simpleand effective means of overcoming physiological seed dormancyand enhancing germination of many temperate tree and shrub species.However, the apparent activation of intracellular repair mechanismsin non-dormant black spruce (Picea mariana) seeds followingmoist chilling, has not previously been reported. The presentcontribution records the beneficial effects of moist chillingafter accelerated ageing (40°C/98% relative humidity) for310 d of black spruce seeds. This treatment was maximallyeffective after 7 d of accelerated ageing, increasing germinationfrom 43 to 61%. Ultrastructural examination of embryo cellsindicated that intracellular activation occurred during moistchilling even when seeds had not been subjected to acceleratedageing, and that the increasing levels of damage accumulatingover the 37 d period of ageing were substantially reversedduring subsequent moist chilling. The results of cold stratificationof non-dormant seeds are discussed in terms of the value ofthis practice in nursery seedling production from seeds thatare of less than the highest quality.Copyright 2000 Annals ofBotany Company Accelerated ageing, black spruce, cold stratification, embryonic axes, germination, moist chilling, Picea mariana, repair mechanisms, ultrastructure 相似文献
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Wei-wei Mao Ting-ting Wang He-ping Zeng Zhi-yu Wang Jian-ping Chen Jian-gang Shen 《Bioorganic & medicinal chemistry letters》2009,19(16):4570-4573
A library of novel 5-hydroxycoumarin and pyranocoumarin derivatives was constructed via silica sulfuric acid-catalyzed pechmann reaction and Pd(0)-catalyzed suzuki coupling in tandem, and their antiproliferative activities against breast cancer cells MCF-7 and MDA-MB-231 were evaluated. The results showed that compounds such as 6b, 6d, 6h, and 6k possess significant antiproliferative activity against MCF-7 cell line with the IC50 values of 7.2, 5.3, 3.3, and 6.5 μM, respectively. 相似文献