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991.
Yunwei Lou Xueqin Tian Chen Sun Miaomiao Song Meijuan Han Yuxin Zhao Yaru Song Xiangfeng Song Wen Zhang Youhai H. Chen Hui Wang 《Cell death & disease》2022,13(4)
Tumor necrosis factor-α-induced protein 8 (TNFAIP8 or TIPE) is a member of the TNFAIP8 family. While TIPE was broadly considered to be pro-cancerous, its precise roles in carcinogenesis especially those of the intestinal tract are not clear. Here, we show that genetic deletion of TIPE in mice exacerbated chemical-induced colitis and colitis-associated colon cancer. Loss of TIPE exacerbated inflammatory responses and inflammation-associated dysbiosis, leading to the activation of NF-κB and STAT3, and it also accelerated dysplasia, DNA damage and proliferation of intestinal epithelial cells. We further show that colon microbiota were essential for increased tumor growth and progression in Tipe−/− mice. The tumor suppressive function of TIPE originated primarily from the non-hematopoietic compartment. Importantly, TIPE was downregulated in human colorectal cancers, and patients with low levels of Tipe mRNA were associated with reduced survival. These results indicate that TIPE serves as an important modulator of colitis and colitis-associated colon cancer.Subject terms: Cancer microenvironment, Chronic inflammation 相似文献
992.
HUW LLOYD STEVEN SEVILLANO RÍOS STUART J. MARSDEN ARMANDO VALDÉS‐VELÁSQUEZ 《Austral ecology》2012,37(4):470-478
Few studies have found strong evidence to suggest that ecotones promote species richness and diversity. In this study we examine the responses of a high‐Andean bird community to changes in vegetation and topographical characteristics across an Andean tree‐line ecotone and adjacent cloud forest and puna grassland vegetation in southern Peru. Over a 6‐month period, birds and vegetation were surveyed using a 100 m fixed‐width Distance Sampling point count method. Vegetation analyses revealed that the tree‐line ecotone represented a distinctive high‐Andean vegetation community that was easily differentiated from the adjacent cloud forest and puna grassland based on changes in tree‐size characteristics and vegetation cover. Bird community composition was strongly seasonal and influenced by a pool of bird species from a wider elevational gradient. There were also clear differences in bird community measures between tree‐line vegetation, cloud forest and puna grassland with species turnover (β‐diversity) most pronounced at the tree‐line. Canonical Correspondence Analysis revealed that the majority of the 81 bird species were associated with tree‐line vegetation. Categorizing patterns of relative abundance of the 42 most common species revealed that the tree‐line ecotone was composed primarily of cloud forest specialists and habitat generalists, with very few species from the puna grassland. Only two species, Thlypopsis ruficeps and Anairetes parulus, both widespread Andean species more typical of montane woodland vegetation edges, were categorized as ecotone specialists. However, our findings were influenced by significant differences in species detectability between all three vegetation communities. Our study highlights the importance of examining ecotones at an appropriate spatial and temporal scale. Selecting a suitable distance between sampling points based on the detection probabilities of the target bird species is essential to obtain an unbiased picture of how ecotones influence avian richness and diversity. 相似文献
993.
Gloria Arratia F. Augusto Chang G. Silvina Menu Marque Guido Rojas M. 《Studies on Neotropical Fauna and Environment》2013,48(3-4):157-194
A new genus of the family Trichomycteridae, Bullockia, and a new species of Trichomycterus are described. Bullockia gen. nov. is a monospecific and relict genus in the freshwaters of Chile. Trichomycterus mendozensis n. sp. is a freshwater relict from Argentina. Preliminary diagnoses of the subfamilies Pygidiinae and Nematogenyinae and the genera Trichomycterus, Hatcheria and Nematogenys are given. 相似文献
994.
995.
Wen‐Qun Fei Jin‐Liang Chen Shang‐Lai Yang Dao‐Xin Li Xin‐Zhang Gao Long Wang 《Nordic Journal of Botany》2019,37(7)
Ligularia dalaolingensis, a new species from Hubei and Hunan, China, is described and illustrated. It belongs to L. sect. Ligularia ser. Speciosae on the basis of its palmate leaf venation, racemose synflorescence and pappus which is slightly shorter than the tube of the tubular corolla. In the series, its closest relatives are assumed to be L. fischeri and L. stenocephala. From L. fischeri, L. dalaolingensis is readily distinguished by smaller basal leaves, shorter synflorescence, narrower involucres and fewer phyllaries and florets; from L. stenocephala, L. dalaolingensis differs by smaller basal leaves, shorter synflorescence as well as broader bracts. A diagnostic key to Chinese species of L. ser. Speciosae with broadly ovate, ovate or ovate‐lanceolate bracts is provided. 相似文献
996.
The Phosphodiesterase 9 Inhibitor PF‐04449613 Promotes Dendritic Spine Formation and Performance Improvement after Motor Learning 下载免费PDF全文
The cyclic nucleotide cGMP is an intracellular second messenger with important roles in neuronal functions and animals' behaviors. The phosphodiesterases (PDEs) are a family of enzymes that hydrolyze the second messengers cGMP and cAMP. Inhibition of phosphodiesterase 9 (PDE9), a main isoform of PDEs hydrolyzing cGMP, has been shown to improve learning and memory as well as cognitive function in rodents. However, the role of PDE9 in regulating neuronal structure and function in vivo remains unclear. Here we used in vivo two‐photon microscopy to investigate the effect of a selective PDE9 inhibitor PF‐04449613 on the activity and plasticity of dendritic spines of layer V pyramidal neurons in the mouse primary motor cortex. We found that administration of PF‐04449613 increased calcium activity of dendrites and dendritic spines of layer V pyramidal neurons in mice under resting and running conditions. Chronic treatment of PF‐04449613 over weeks increased dendritic spine formation and elimination under basal conditions. Furthermore, PF‐04449613 treatment over 1–7 days increased the formation and survival of new spines as well as performance improvement after rotarod motor training. Taken together, our studies suggest that elevating the level of cGMP with the PDE9 inhibitor PF‐04449613 increases synaptic calcium activity and learning‐dependent synaptic plasticity, thereby contributing to performance improvement after learning. © 2018 Wiley Periodicals, Inc. Develop Neurobiol 00: 000–000, 2018 相似文献
997.
麻叶千里光抗菌化学成分的研究(Ⅲ) 总被引:6,自引:0,他引:6
以革兰氏阳性菌金黄色葡萄球菌(Staphylococcus aureus)、枯草芽孢杆菌(Bacillus subtilis)和阴性菌大肠杆菌(Escherichia coli)为受试菌,采用体外抑菌圈法追踪抗菌活性部分。利用各种色谱技术对正丁醇萃取部分进行分离纯化,根据理化性质和谱学数据进行结构鉴定。从麻叶千里光的水提醇沉物的正丁醇萃取部分分离得到3个化合物:苄基-O-α-L-广吡喃阿拉伯糖基(1→6)-β-D-吡喃葡糖苷(1)、(6S,9S)-6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡糖苷(2)和(6S,9R)-6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡糖苷(3)。它们均为首次从该属植物中分离得到。 相似文献
998.
A hidden aggregation‐prone structure in the heart of hypoxia inducible factor prolyl hydroxylase 下载免费PDF全文
Hamid Hadi‐Alijanvand Elizabeth A. Proctor Feng Ding Nikolay V. Dokholyan Ali A. Moosavi‐Movahedi 《Proteins》2016,84(5):611-623
Prolyl hydroxylase domain‐containing protein 2 (PHD2), as one of the most important regulators of angiogenesis and metastasis of cancer cells, is a promising target for cancer therapy drug design. Progressive studies imply that abnormality in PHD2 function may be due to misfolding. Therefore, study of the PHD2 unfolding pathway paves the way for a better understanding of the influence of PHD2 mutations and cancer cell metabolites on the protein folding pathway. We study the unfolding of the PHD2 catalytic domain using differential scanning calorimetry (DSC), fluorescence spectroscopy, and discrete molecular dynamics simulations (DMD). Using computational and experimental techniques, we find that PHD2 undergoes four transitions along the thermal unfolding pathway. To illustrate PHD2 unfolding events in atomic detail, we utilize DMD simulations. Analysis of computational results indicates an intermediate species in the PHD2 unfolding pathway that may enhance aggregation propensity, explaining mutation‐independent PHD2 malfunction. Proteins 2016; 84:611–623. © 2016 Wiley Periodicals, Inc. 相似文献
999.
The paper reports 13 species from Yaoluoping National Nature Reserve,Anhui,China,including a new species and a new subspecies,Tipula (Emodotipula) alexanderi Men,sp.nov.and Nephrotoma impigra anqingensis Men,subsp.nov.The female of Libnotes (Libnotes) pseudonohirai Men,2015 is described and illustrated for the first time.The males of Holorusia henana Yang,1999 and Tipula (Vestiplex)jiangi Yang & Yang,1991 are redescribed and illustrated with new morphological characters.A key to all species is provided. 相似文献
1000.
Marinés de la Peña‐Domene Henry F. Howe Emiliano Cruz‐León Rita Jiménez‐Rolland Cesar Lozano‐Huerta Cristina Martínez‐Garza 《Oikos》2017,126(3):410-419
Recognition that tree recruitment depends on the balance between seed arrival and seedling survival has led to a surge of interest in seed‐dispersal limitation and seedling‐establishment limitation in primary forests. Virtually unaddressed are comparisons of this balance in mature and early successional habitats. We assessed seed rain and seedling recruitment dynamics of tree species in primary forest, secondary forest and pasture released from grazing in a tropical agricultural landscape. Seed to seedling ratios (seed effectiveness; Φi) for 43 species in southern Mexico determined differences in the extent to which seeds produced seedlings by habitat, life history, and dispersal mode. Reproductive potential as estimated by the transition from seed rain to seedling recruitment, differed by habitats, and varied dramatically by life history and dispersal mode. Expected recruit densities (Eit) were higher for animal‐dispersed than wind‐dispersed species, and for non‐pioneer than pioneer species. Non‐pioneers and animal‐dispersed species had higher expected relative recruit abundance (εit) in primary forest (median of 4 seeds recruit?1) whereas in secondary forest wind‐dispersed pioneers had the highest expected relative recruit abundance (median of 16 seeds per recruit). In pastures, wind‐dispersed pioneer species were most successful with many more seeds per recruit (median of 291) than both forest habitats. Seeds per recruit (Φi) appeared to decrease with increase in seed mass for 43 species for which data were available (r = –0.55, P < 0.001). This was associated with a negative correlation of Φi with seed size in primary forest (r = –0.50, P = 0.08 for 13 species); Φi was not correlated with seed size in secondary forest (n = 16) or pasture (n = 14). Metrics of seeds per recruit, expected recruit density and expected relative recruit abundance dramatically illustrate differences in barriers to recruitment in successional habitats. 相似文献