72 research outputs found
Appraisal of the Sri Lanka Dairy Sector volume 2: Main report
从蛙虹彩病毒(Rana grylio virus,RGV)中克隆出一个虹彩病毒科的序列保守基因RGV-12L,序列分析表明该基因全长894 bp,编码一个含297个氨基酸的多肽,分子量为33 kD。构建包含该基因全长的原核表达载体,进行原核表达,获得了分子量约53 kD的融合蛋白。将融合蛋白经腹腔注射免疫小鼠,制备出鼠抗RGV-12L血清。通过RT-PCR和Western blotting分析RGV感染细胞后RGV-12L的转录时序,感染4h可以在RNA水平检测到RGV-12L的转录,感染8h可以在蛋白水平检测到RGV-12L的表达。用DNA复制抑制剂阿糖胞苷(Arac)进行药物抑制实验,鉴定出RGV-12L是一个晚期基因。免疫荧光分析显示RGV-12L分布于感染细胞的细胞核和细胞质中,在病毒加工厂中也有该蛋白的分布,提示该基因可能与病毒的装配、释放有关
ECONOMIC IMPACTS OF CLIMATE CHANGE ON SOUTHERN FORESTS
A multiperiod regional mathematical programming model is used to evaluate the potential economic impacts of global climatic change on the southern U.S. forestry sector. Scenarios for forest biological response to climate change are developed for small and large changes in forest growth rates. Resulting changes in timber supply have economic impacts on producers and consumers in forest products markets, both nationally and regionally. Conclusions include outer dimensions of global climate change impacts and potential effects of smaller biological responses on the forestry sector both nationally and in the U.S. South. Relative impacts are found to be larger for producers than for consumers, and southern producers experience relatively greater changes in economic welfare.Resource /Energy Economics and Policy,
Immediate Early and Early Lytic Cycle Proteins Are Frequent Targets of the Epstein-Barr Virus–induced Cytotoxic T Cell Response
Epstein-Barr virus (EBV), a human γ-herpesvirus, can establish both nonproductive (latent) and productive (lytic) infections. Although the CD8+ cytotoxic T lymphocyte (CTL) response to latently infected cells is well characterized, very little is known about T cell controls over lytic infection; this imbalance in our understanding belies the importance of virus-replicative lesions in several aspects of EBV disease pathogenesis. The present work shows that the primary CD8+ CTL response to EBV in infectious mononucleosis patients contains multiple lytic antigen-specific reactivities at levels at least as high as those seen against latent antigens; similar reactivities are also detectable in CTL memory. Clonal analysis revealed individual responses to the two immediate early proteins BZLF1 and BRLF1, and to three (BMLF1, BMRF1, and BALF2) of the six early proteins tested. In several cases, the peptide epitope and HLA-restricting determinant recognized by these CTLs has been defined, one unusual feature being the number of responses restricted through HLA-C alleles. The work strongly suggests that EBVreplicative lesions are subject to direct CTL control in vivo and that immediate early and early proteins are frequently the immunodominant targets. This contrasts with findings in α- and β-herpesvirus systems (herpes simplex, cytomegalovirus) where viral interference with the antigen-processing pathway during lytic infection renders immediate early and early proteins much less immunogenic. The unique capacity of γ-herpesvirus to amplify the viral load in vivo through a latent growth-transforming infection may have rendered these agents less dependent upon viral replication as a means of successfully colonizing their hosts
Navigating the transcriptional roadmap regulating plant secondary cell wall deposition
The current status of lignocellulosic biomass as an invaluable resource in industry, agriculture, and health has spurred increased interest in understanding the transcriptional regulation of secondary cell wall (SCW) biosynthesis. The last decade of research has revealed an extensive network of NAC, MYB and other families of transcription factors regulating Arabidopsis SCW biosynthesis, and numerous studies have explored SCW-related transcription factors in other dicots and monocots. Whilst the general structure of the Arabidopsis network has been a topic of several reviews, they have not comprehensively represented the detailed protein-DNA and protein-protein interactions described in the literature, and an understanding of network dynamics and functionality has not yet been achieved for SCW formation. Furthermore the methodologies employed in studies of SCW transcriptional regulation have not received much attention, especially in the case of non-model organisms. In this review, we have reconstructed the most exhaustive literature-based network representations to date of SCW transcriptional regulation in Arabidopsis. We include a manipulable Cytoscape representation of the Arabidopsis SCW transcriptional network to aid in future studies, along with a list of supporting literature for each documented interaction. Amongst other topics, we discuss the various components of the network, its evolutionary conservation in plants, putative modules and dynamic mechanisms that may influence network function, and the approaches that have been employed in network inference. Future research should aim to better understand network function and its response to dynamic perturbations, whilst the development and application of genome-wide approaches such as ChIP-seq and systems genetics are in progress for the study of SCW transcriptional regulation in non-model organisms.The Mandela Rhodes Foundation and National Research
Foundation of South Africahttp://www.frontiersin.orgam201
Expanded human blood-derived γδT cells display potent antigen-presentation functions
Cell-based immunotherapy strategies target tumors directly (via cytolytic effector cells) or aim at mobilizing endogenous anti-tumor immunity. The latter approach includes dendritic cells (DC) most frequently in the form of in vitro cultured peripheral blood monocytes-derived DC. Human blood \u3b3\u3b4T cells are selective for a single class of non-peptide agonists ("phosphoantigens") and develop into potent antigen-presenting cells (APC), termed \u3b3\u3b4T-APC within 1-3 days of in vitro culture. Availability of large numbers of \u3b3\u3b4T-APC would be advantageous for use as a novel cellular vaccine. We here report optimal \u3b3\u3b4T cell expansion (>107cells/ml blood) when peripheral blood mononuclear cells (PBMC) from healthy individuals and melanoma patients were stimulated with zoledronate and then cultured for 14 days in the presence of IL-2 and IL-15, yielding \u3b3\u3b4T cell cultures of variable purity (77 \ub1 21 and 56 \ub1 26%, respectively). They resembled effector memory \u3b1\u3b2T (TEM) cells and retained full functionality as assessed by in vitro tumor cell killing as well as secretion of pro-inflammatory cytokines (IFN\u3b3, TNF\u3b1) and cell proliferation in response to stimulation with phosphoantigens. Importantly, day 14 \u3b3\u3b4T cells expressed numerous APC-related cell surface markers and, in agreement, displayed potent in vitro APC functions. Day 14 \u3b3\u3b4T cells from PBMC of patients with cancer were equally effective as their counterparts derived from blood of healthy individuals and triggered potent CD8+ \u3b1\u3b2T cell responses following processing and cross-presentation of simple (influenza M1) and complex (tuberculin purified protein derivative) protein antigens. Of note, and in clear contrast to peripheral blood \u3b3\u3b4T cells, the ability of day 14 \u3b3\u3b4T cells to trigger antigen-specific \u3b1\u3b2T cell responses did not depend on re-stimulation. We conclude that day 14 \u3b3\u3b4T cell cultures provide a convenient source of autologous APC for use in immunotherapy of patients with various cancers
Manipulating glucocorticoids in wild animals: Basic and applied perspectives
One of the most comprehensively studied responses to stressors in vertebrates is the endogenous production and regulation of glucocorticoids (GCs). Extensive laboratory research using experimental elevation of GCs in model species is instrumental in learning about stressor-induced physiological and behavioural mechanisms; however, such studies fail to inform our understanding of ecological and evolutionary processes in the wild. We reviewed emerging research that has used GC manipulations in wild vertebrates to assess GC-mediated effects on survival, physiology, behaviour, reproduction and offspring quality. Within and across taxa, exogenous manipulation of GCs increased, decreased or had no effect on traits examined in the reviewed studies. The notable diversity in r
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