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991.
B. A. McGivney B. Hernandez L. M. Katz D. E. MacHugh S. P. McGovern A. C. Parnell H. L. Wiencko E. W. Hill 《Animal genetics》2019,50(4):347-357
Durability traits in Thoroughbred horses are heritable, economically valuable and may affect horse welfare. The aims of this study were to test the hypotheses that (i) durability traits are heritable and (ii) genetic data may be used to predict a horse's potential to have a racecourse start. Heritability for the phenotype ‘number of 2‐ and 3‐year‐old starts’ was estimated to be = 0.11 ± 0.02 (n = 4499). A genome‐wide association study identified SNP contributions to the trait. The neurotrimin (NTM), opioid‐binding protein/cell adhesion molecule like (OPCML) and prolylcarboxypeptidase (PRCP) genes were identified as candidate genes associated with the trait. NTM functions in brain development and has been shown to have been selected during the domestication of the horse. PRCP is an established expression quantitative trait locus involved in the interaction between voluntary exercise and body composition in mice. We hypothesise that variation at these loci contributes to the motivation of the horse to exercise, which may influence its response to the demands of the training and racing environment. A random forest with mixed effects (RFME) model identified a set of SNPs that contributed to 24.7% of the heritable variation in the trait. In an independent validation set (n = 528 horses), the cohort with high genetic potential for a racecourse start had significantly fewer unraced horses (16% unraced) than did low (27% unraced) potential horses and had more favourable race outcomes among those that raced. Therefore, the information from SNPs included in the model may be used to predict horses with a greater chance of a racecourse start. 相似文献
992.
Nick Bowman Dong Liu Patrick Paczkowski Jon Chen John Rossi Sean Mackay Adrian Bot Jing Zhou 《Proteomics》2020,20(13)
Highly multiplexed single‐cell functional proteomics has emerged as one of the next‐generation toolkits for a deeper understanding of functional heterogeneity in cell. Different from the conventional population‐based bulk and single‐cell RNA‐Seq assays, the microchip‐based proteomics at the single‐cell resolution enables a unique identification of highly polyfunctional cell subsets that co‐secrete many proteins from live single cells and most importantly correlate with patient response to a therapy. The 32‐plex IsoCode chip technology has defined a polyfunctional strength index (PSI) of pre‐infusion anti‐CD19 chimeric antigen receptor (CAR)‐T products, that is significantly associated with patient response to the CAR‐T cell therapy. To complement the clinical relevance of the PSI, a comprehensive visualization toolkit of 3D uniform manifold approximation and projection (UMAP) and t‐distributed stochastic neighbor embedding (t‐SNE) in a proteomic analysis pipeline is developed, providing more advanced analytical algorithms for more intuitive data visualizations. The UMAP and t‐SNE of anti‐CD19 CAR‐T products reveal distinct cytokine profiles between nonresponders and responders and demonstrate a marked upregulation of antitumor‐associated cytokine signatures in CAR‐T cells from responding patients. Using this powerful while user‐friendly analytical tool, the multi‐dimensional single‐cell data can be dissected from complex immune responses and uncover underlying mechanisms, which can promote correlative biomarker discovery, improved bioprocessing, and personalized treatment development. 相似文献
993.
Zhong Huang Qiang Chen Brooke Hjelm Charles Arntzen Hugh Mason 《Biotechnology and bioengineering》2009,103(4):706-714
Recombinant virus‐like particles (VLPs) represent a safe and effective vaccine strategy. We previously described a stable transgenic plant system for inexpensive production and oral delivery of VLP vaccines. However, the relatively low‐level antigen accumulation and long‐time frame to produce transgenic plants are the two major roadblocks in the practical development of plant‐based VLP production. In this article, we describe the optimization of geminivirus‐derived DNA replicon vectors for rapid, high‐yield plant‐based production of VLPs. Co‐delivery of bean yellow dwarf virus (BeYDV)‐derived vector and Rep/RepA‐supplying vector by agroinfiltration of Nicotiana benthamiana leaves resulted in efficient replicon amplification and robust protein production within 5 days. Co‐expression of the P19 protein of tomato bush stunt virus, a gene silencing inhibitor, further enhanced VLP accumulation by stabilizing the mRNA. With this system, hepatitis B core antigen (HBc) and Norwalk virus capsid protein (NVCP) were produced at 0.80 and 0.34 mg/g leaf fresh weight, respectively. Sedimentation analysis and electron microscopy of transiently expressed antigens verified the efficient assembly of VLPs. Furthermore, a single replicon vector containing a built‐in Rep/RepA cassette without P19 drove protein expression at similar levels as the three‐component system. These results demonstrate the advantages of fast and high‐level production of VLP‐based vaccines using the BeYDV‐derived DNA replicon system for transient expression in plants. Biotechnol. Bioeng. 2009;103: 706–714. © 2009 Wiley Periodicals, Inc. 相似文献
994.
Inter-patient variation in efficacy of five oncolytic adenovirus candidates for ovarian cancer therapy 总被引:2,自引:0,他引:2
995.
室内研究了蓝蝽Zicrona caerula(Linnaeus)对马铃薯甲虫Leptinotarsa decemlineata(Say)低龄幼虫的捕食功能反应和选择效应。HollingII型圆盘方程和HollingⅢ型新模型拟合结果共同显示,蓝蝽若虫对马铃薯甲虫1龄幼虫的捕食量随着龄期的增加而增大;4、5龄若虫及成虫的捕食量均在17头以上。由HollingII模型获得蓝蝽对马铃薯甲虫1龄幼虫的控制能力为2龄<3龄<4龄<5龄<成虫;随着食物密度的增加,蓝蝽各虫态的寻找效应逐渐下降。田间防治马铃薯甲虫1龄幼虫时,2~5龄蓝蝽若虫及成虫的最佳益害比应该分别为1∶2、1∶4、1∶13、1∶14、1∶13,然而,食物选择效应显示蓝蝽原生境中猎物-兰叶甲可能会对防治产生影响。 相似文献
996.
997.
Vijayakumar Maheshwari Malathi Sushil K. Jalali Dandinashivara K. Sidde Gowda Muthugounder Mohan Thiruvengadam Venkatesan 《Insect Science》2017,24(1):35-46
The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the major pests of rice throughout Asia. Extensive use of insecticides for suppressing N. lugens has resulted in the development of insecticide resistance leading to frequent control failures in the field. The aim of the present study was to evaluate resistance in the field populations of N. lugens from major rice growing states of South India to various insecticides. We also determined the activity of detoxifying enzymes (esterases [ESTs], glutathione S‐transferases [GSTs], and mixed‐function oxidases [MFOs]). Moderate levels of resistance were detected in the field populations to acephate, thiamethoxam and buprofezin (resistance factors 1.05–20.92 fold, 4.52–14.99 fold, and 1.00–18.09 fold, respectively) as compared with susceptible strain while there were low levels of resistance to imidacloprid (resistance factor 1.23–6.70 fold) and complete sensitivity to etofenoprox (resistance factor 1.05–1.66 fold). EST activities in the field populations were 1.06 to 3.09 times higher than the susceptible strain while for GST and MFO the ratios varied from 1.29 to 3.41 and 1.03 to 1.76, respectively. The EST activity was found to be correlated to acephate resistance (r = 0.999, P ≥ 0.001). The high selection pressure of organophosphate, neonicotinoid, and insect growth regulator (IGR) in the field is likely to be contributing for resistance in BPH to multiple insecticides, leading to control failures. The results obtained will be beneficial to IPM recommendations for the use of effective insecticides against BPH. 相似文献
998.
Kerong Zhang Conghe Song Yulong Zhang Haishan Dang Xiaoli Cheng Quanfa Zhang 《Global Change Biology》2018,24(1):536-551
Knowledge of nutrient storage and partitioning in forests is imperative for ecosystem models and ecological theory. Whether the nutrients (N, P, K, Ca, and Mg) stored in forest biomass and their partitioning patterns vary systematically across climatic gradients remains unknown. Here, we explored the global‐scale patterns of nutrient density and partitioning using a newly compiled dataset including 372 forest stands. We found that temperature and precipitation were key factors driving the nutrients stored in living biomass of forests at global scale. The N, K, and Mg stored in living biomass tended to be greater in increasingly warm climates. The mean biomass N density was 577.0, 530.4, 513.2, and 336.7 kg/ha for tropical, subtropical, temperate, and boreal forests, respectively. Around 76% of the variation in biomass N density could be accounted by the empirical model combining biomass density, phylogeny (i.e., angiosperm, gymnosperm), and the interaction of mean annual temperature and precipitation. Climate, stand age, and biomass density significantly affected nutrients partitioning at forest community level. The fractional distribution of nutrients to roots decreased significantly with temperature, suggesting that forests in cold climates allocate greater nutrients to roots. Gymnosperm forests tended to allocate more nutrients to leaves as compared with angiosperm forests, whereas the angiosperm forests distributed more nutrients in stems. The nutrient‐based Root:Shoot ratios (R:S), averaged 0.30 for R:SN, 0.36 for R:SP, 0.32 for R:SK, 0.27 for R:SCa, and 0.35 for R:SMg, respectively. The scaling exponents of the relationships describing root nutrients as a function of shoot nutrients were more than 1.0, suggesting that as nutrient allocated to shoot increases, nutrient allocated to roots increases faster than linearly with nutrient in shoot. Soil type significantly affected the total N, P, K, Ca, and Mg stored in living biomass of forests, and the Acrisols group displayed the lowest P, K, Ca, and Mg. 相似文献
999.
1000.
The role of NCAM in auditory fear conditioning and its modulation by stress: a focus on the amygdala
Chronic stress in rodents was shown to induce structural shrinkage and functional alterations in the hippocampus that were linked to spatial memory impairments. Effects of chronic stress on the amygdala have been linked to a facilitation of fear conditioning. Although the underlying molecular mechanisms are still poorly understood, increasing evidence highlights the neural cell adhesion molecule (NCAM) as an important molecular mediator of stress‐induced structural and functional alterations. In this study, we investigated whether altered NCAM expression levels in the amygdala might be related to stress‐induced enhancement of auditory fear conditioning and anxiety‐like behavior. In adult C57BL/6J wild‐type mice, chronic unpredictable stress resulted in an isoform‐specific increase of NCAM expression (NCAM‐140 and NCAM‐180) in the amygdala, as well as enhanced auditory fear conditioning and anxiety‐like behavior. Strikingly, forebrain‐specific conditional NCAM‐deficient mice (NCAM‐floxed mice that express the cre‐recombinase under the control of the promoter of the α‐subunit of the calcium‐calmodulin‐dependent protein kinase II), whose amygdala NCAM expression levels are reduced, displayed impaired auditory fear conditioning which was not altered following chronic stress exposure. Likewise, chronic stress in these conditional NCAM‐deficient mice did not modify NCAM expression levels in the amygdala or hippocampus, while they showed enhanced anxiety‐like behavior, questioning the involvement of NCAM in this type of behavior. Together, our results strongly support the involvement of NCAM in the amygdala in the consolidation of auditory fear conditioning and highlight increased NCAM expression in the amygdala among the mechanisms whereby stress facilitates fear conditioning processes. 相似文献