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Joanne K. Gardner Cyril D. S. Mamotte Priya Patel Teong Ling Yeoh Connie Jackaman Delia J. Nelson 《PloS one》2015,10(4)
Dendritic cells (DCs) play an important role in the generation of anti-cancer immune responses, however there is evidence that DCs in cancer patients are dysfunctional. Lipid accumulation driven by tumor-derived factors has recently been shown to contribute to DC dysfunction in several human cancers, but has not yet been examined in mesothelioma. This study investigated if mesothelioma tumor cells and/or their secreted factors promote increases in DC lipid content and modulate DC function. Human monocyte-derived DCs (MoDCs) were exposed to human mesothelioma tumor cells and tumor-derived factors in the presence or absence of lipoproteins. The data showed that immature MoDCs exposed to mesothelioma cells or factors contained increased lipid levels relative to control DCs. Lipid accumulation was associated with reduced antigen processing ability (measured using a DQ OVA assay), upregulation of the co-stimulatory molecule, CD86, and production of the tolerogenic cytokine, IL-10. Increases in DC lipid content were further enhanced by co-exposure to mesothelioma-derived factors and triglyceride-rich lipoproteins, but not low-density lipoproteins. In vivo studies using a murine mesothelioma model showed that the lipid content of tumor-infiltrating CD4+CD8α- DCs, CD4-CD8α- DCs DCs and plasmacytoid DCs increased with tumor progression. Moreover, increasing tumor burden was associated with reduced proliferation of tumor-antigen-specific CD8+ T cells in tumor-draining lymph nodes. This study shows that mesothelioma promotes DC lipid acquisition, which is associated with altered activation status and reduced capacity to process and present antigens, which may impair the ability of DCs to generate effective anti mesothelioma T cell responses. 相似文献
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Xingyu Zhu Qianqian Gao Genhua Zhao Heng Wang Ling Liu Zhipeng Chen Yijun Chen Li Wu Zisheng Xu Weidong Li 《Biological trace element research》2018,184(1):136-147
To evaluate and compare the effect of raw and processed pyritum on tibial defect healing, 32 male Sprague Dawley rats were randomly divided into four groups. After tibial defect, animals were produced and grouped: sham and control group were orally administrated with distilled water (1 mL/100 g), while treatment groups were given aqueous extracts of raw and processed pyritum (1.5 g/kg) for successive 42 days. Radiographic examination showed that bone defect healing effect of the treatment groups was obviously superior compared to that of the control group. Bone mineral density of whole tibia was increased significantly after treating with pyritum. Inductively coupled plasma-optical emission spectrometry showed that the contents of Ca, P, and Mg in callus significantly increased in the treatment groups comparing with the control. Moreover, serological analysis showed that the concentration of serum phosphorus of the treatment groups significantly increased compared with that of the control group. By in vitro study, we have evaluated the effects of drug-containing serum of raw and processed pyritum on osteoblasts. It was manifested that both the drug-containing sera of raw and processed pyritum significantly increased the mRNA levels of alkaline phosphatase and collagen type I. Protein levels of phosphorylated Smad2/3 also increased. The mRNA levels of osteocalcin and transforming growth factor β (TGF-β) type I and II receptors, as well as the protein levels of TGF-β1 in the processed groups, were higher than those in the control. In summary, both raw and processed pyritum-containing sera exhibited positive effects on osteoblasts, which maybe via the TGF-β1/Smad signaling pathway. Notably, the tibia defect healing effect of pyritum was significantly enhanced after processing. 相似文献
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Phylogeny of Stephanidae (Hymenoptera: Apocrita) with a new genus from Upper Cretaceous Myanmar amber 下载免费PDF全文
LONFGENG LI ALEXANDR P. RASNITSYN CONRAD C. LABANDEIRA CHUNGKUN SHIH DONG REN 《Systematic Entomology》2017,42(1):194-203
A new wasp species, Lagenostephanus lii Li, Rasnitsyn, Shih and Ren gen. et sp.n. , is assigned to Stephaninae (Hymenoptera: Stephanidae). The specimen is described from the lowermost Upper Cretaceous Myanmar (Burmese) amber. This is the second stephanid wasp described from Myanmar amber after Kronostephanus zigrasi Engel & Grimaldi, representing the earliest fossil occurrences of Stephanidae. Based on morphological characters of all extant and extinct genera, a phylogenetic analysis of Stephanidae was conducted. The results indicate that Schlettereriinae and Stephaninae are monophyletic, whereas Electrostephanus Brues, as the only genus within Electrostephaninae, belongs to Stephaninae. Therefore, we propose a synonymy of Electrostephaninae with Stephaninae. Based on the fossil evidence, we infer that the family of Stephanidae was significantly diverse in the Late Cretaceous and that they originated during the Early Cretaceous or late Jurassic. A key to genera of Stephanidae is provided. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:C082C245-8FD3-42B0-880F-94333286500B . 相似文献
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20世纪90年代以来中国生态空间演化的时空格局和梯度效应 总被引:3,自引:0,他引:3
改革开放以来中国经济和城市化的快速发展促使生产和生活空间挤占大量生态空间,系统认识和评估我国生态空间演化的宏观格局和过程对于生态文明建设具有重要的理论和现实意义。为揭示全国生态空间变化的时空过程,在对生态空间内涵进行界定的基础上,结合全国尺度时序土地利用数据构建生态空间分类体系,并评估1990-2015年中国生态空间演化特征。结果表明:1990-2015年中国生态用地面积持续减少,主要向半生态用地转变,发生在重要的粮食生产区域及周边;半生态用地面积波动明显,前期主要表现为不断扩张,后期大量转换为弱生态用地,发生在主要城市群地区;弱生态用地持续扩张,与城镇化进程不断加速相关。中国生态空间演变过程表现出一定的区域差异和梯度效应,不同区域生态空间变化发生的拐点时间有所不同,呈现"自东向西、由南到北"的3级梯度特征,区域生态空间状况与经济发展战略及生态空间管控具有较强的相关性。本研究对于国家生态空间管控近远期战略方案制订具有一定启示,建议处于不同梯度的各地区应基于区域生态空间演化所处阶段和不同驱动机制,确定分区域生态空间安全红线目标和生态空间管控方案。 相似文献