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91.
Shan Gao Michaela C. Strüder‐Kypke Khaled A. S. Al‐Rasheid Xiaofeng Lin Weibo Song 《Zoologica scripta》2010,39(3):305-313
Gao, S., Strüder‐Kypke, M.C., Al‐Rasheid, K.A.S., Lin, X. & Song, W. (2010). Molecular phylogeny of three ambiguous ciliate genera: Kentrophoros, Trachelolophos and Trachelotractus (Alveolata, Ciliophora).—Zoologica Scripta, 39, 305–313. Very few molecular studies on the phylogeny of the karyorelictean ciliates have been carried out because data of this highly ambiguous group are extremely scarce. In the present study, we sequenced the small subunit ribosomal RNA genes of three morphospecies representing two karyorelictean genera, Kentrophoros, Trachelolophos, and one haptorid, Trachelotractus, isolated from the South and East China Seas. The phylogenetic trees constructed using Bayesian inference, maximum likelihood, maximum parsimony and neighbor‐joining methods yielded essentially similar topologies. The class Karyorelictea is depicted as a monophyletic clade, closely related to the class Heterotrichea. The generic concept of the family Trachelocercidae is confirmed by the clustering of Trachelolophos and Tracheloraphis with high bootstrap support; nevertheless, the order Loxodida is paraphyletic. The transfer of the morphotype Trachelocerca entzi Kahl, 1927 to the class Litostomatea and into the new haptorid genus Trachelotractus, as suggested by previous researchers based on morphological studies, is consistently supported by our molecular analyses. In addition, the poorly known species Parduczia orbis occupies a well‐supported position basal to the Geleia clade, justifying the separation of these genera from one another. 相似文献
92.
Zhao Shan Li Zhiyong Xin Xiangdong Zhang Bei Jiang Xizhi Thomas Attaribo Charles Asakiya Zhang Lei Gui Zhongzheng 《International journal of peptide research and therapeutics》2020,26(4):1913-1921
International Journal of Peptide Research and Therapeutics - Silk fibroin is an excellent raw material for medical products as it shows remarkable biocompatibility, water-based processing, and... 相似文献
93.
MicroRNAs (miRNAs) have been found to play a key role in drug resistance. In the current study, we aimed to explore the potential role of miR‐126 in trastuzumab resistance in breast cancer cells. We found that the trastuzumab‐resistant cell lines SKBR3/TR and BT474/TR had low expression of miR‐126 and increased ability to migrate and invade. The resistance, invasion and mobilization abilities of the cells resistant to trastuzumab were reduced by ectopic expression of miR‐126 mimics. In comparison, inhibition of miR‐126 in SKBR3 parental cells had the opposite effect of an increased resistance to trastuzumab as well as invasion and migration. It was also found that miR‐126 directly targets PIK3R2 in breast cancer cells. PIK3R2‐knockdown cells showed decreased resistance to trastuzumab, while overexpression of PIK3R2 increased trastuzumab resistance. In addition, our finding showed that overexpression of miR‐126 reduced resistance to trastuzumab in the trastuzumab‐resistant cells and that inhibition of the PIK3R2/PI3K/AKT/mTOR signalling pathway was involved in this effect. SKBR3/TR cells also showed increased sensitivity to trastuzumab mediated by miR‐126 in vivo. In conclusion, the above findings demonstrated that overexpression of miR‐126 or down‐regulation of its target gene may be a potential approach to overcome trastuzumab resistance in breast cancer cells. 相似文献
94.
Wei Peng Min Luo Xiandong Xu Kang Jiang Ming Peng Dechao Chen Ting‐Shan Chan Yongwen Tan 《Liver Transplantation》2020,10(25)
The electrochemical nitrogen reduction reaction (NRR) process usually suffers extremely low Faradaic efficiency and ammonia yields due to sluggish N?N dissociation. Herein, single‐atomic ruthenium modified Mo2CTX MXene nanosheets as an efficient electrocatalyst for nitrogen fixation at ambient conditions are reported. The catalyst achieves a Faradaic efficiency of 25.77% and ammonia yield rate of 40.57 µg h?1 mg?1 at ‐0.3 V versus the reversible hydrogen electrode in 0.5 m K2SO4 solution. Operando X‐ray absorption spectroscopy studies and density functional theory calculations reveal that single‐atomic Ru anchored on MXene nanosheets act as important electron back‐donation centers for N2 activation, which can not only promote nitrogen adsorption and activation behavior of the catalyst, but also lower the thermodynamic energy barrier of the first hydrogenation step. This work opens up a promising avenue to manipulate catalytic performance of electrocatalysts utilizing an atomic‐level engineering strategy. 相似文献
95.
Yi‐Lin Chen Gao‐Xiong Wang Bei‐An Lin Jing‐Shan Huang 《Cell biology international》2020,44(5):1224-1236
This work aimed to investigate miR‐93‐5p expression in tumor tissue and its in vitro effects in colorectal cancer (CRC) by targeting programmed death ligand‐1 (PD‐L1). MiR‐93‐5p and PD‐L1 expression was detected in CRC and adjacent normal tissues by quantitative real‐time polymerase chain reaction and immunohistochemistry. The correlation between miR‐93‐5p and PD‐L1 was validated by a dual‐luciferase reporter assay. HCT116 and SW480 cells were divided into blank, miR‐NC, miR‐93‐5p mimics, miR‐93‐5p inhibitor, PD‐L1 small interfering RNA (siRNA) and miR‐93‐5p inhibitor + PD‐L1 siRNA groups, and wound‐healing and transwell assays were performed to detect cell migration and invasion, respectively. Protein expression was measured by western blotting. The secretion of cytokines was detected in the CRC cell/T coculture models. MiR‐93‐5p was downregulated in CRC tissues with upregulated PD‐L1. In PD‐L1‐negative patients, miR‐93‐5p expression was increased compared with that in PD‐L1‐positive patients. MiR‐93‐5p and PD‐L1 expression levels were associated with the tumor differentiation, lymphatic metastasis, TNM, Duke's stage, and prognosis of CRC. PD‐L1 siRNA weakened the migration and invasion abilities via decreased expression of matrix metalloproteinase‐1 (MMP‐1), ‐2, and ‐9, and these effects were abolished by the miR‐93‐5p inhibitor. Additionally, anti‐PD‐L1 upregulated the expressions of interleukin‐2 (IL‐2), tumor necrosis factor‐α (TNF‐α), and interferon γ (IFN‐γ) in the coculture of T cells with CRC cells, but downregulated the expressions of IL‐1β, IL‐10, and TGF‐β. However, these changes were partially reversed by miR‐93‐5p inhibition. miR‐93‐5p is expected to be a novel target for CRC treatment since it decreases the migration and invasion, as well as the immune evasion, of CRC cells via targeting PD‐L1. 相似文献
96.
Claire S. Teitelbaum Caroline R. Amoroso Shan Huang T. Jonathan Davies Julie Rushmore John M. Drake Patrick R. Stephens James E. Byers Ania A. Majewska Charles L. Nunn 《Ecography》2020,43(9):1316-1328
Understanding the drivers of biodiversity is important for forecasting changes in the distribution of life on earth. However, most studies of biodiversity are limited by uneven sampling effort, with some regions or taxa better sampled than others. Numerous methods have been developed to account for differences in sampling effort, but most methods were developed for systematic surveys in which all study units are sampled using the same design and assemblages are sampled randomly. Databases compiled from multiple sources, such as from the literature, often violate these assumptions because they are composed of studies that vary widely in their goals and methods. Here, we compared the performance of several popular methods for estimating parasite diversity based on a large and widely used parasite database, the Global Mammal Parasite Database (GMPD). We created artificial datasets of host–parasite interactions based on the structure of the GMPD, then used these datasets to evaluate which methods best control for differential sampling effort. We evaluated the precision and bias of seven methods, including species accumulation and nonparametric diversity estimators, compared to analyzing the raw data without controlling for sampling variation. We find that nonparametric estimators, and particularly the Chao2 and second-order jackknife estimators, perform better than other methods. However, these estimators still perform poorly relative to systematic sampling, and effect sizes should be interpreted with caution because they tend to be lower than actual effect sizes. Overall, these estimators are more effective in comparative studies than for producing true estimates of diversity. We make recommendations for future sampling strategies and statistical methods that would improve estimates of global parasite diversity. 相似文献
97.
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99.
Microbulbifer hainanensis sp. nov., a moderately halopilic bacterium isolated from mangrove sediment
Cheng Yuping Zhu Suting Guo Chaobo Xie Feilu Jung Dawoon Li Shengying Zhang Weiyan He Shan 《Antonie van Leeuwenhoek》2021,114(7):1033-1042
Antonie van Leeuwenhoek - A new bacterium was successfully isolated from a mangrove sediment sample in Haikou City, Hainan Province, China. The organism is a Gram-negative, rod-shaped, non-motile... 相似文献
100.
甘蔗(Saccharum spp.)是世界也是中国主要的糖料作物.由甘蔗黑穗病菌(Sporisorium scitamineum)引起的甘蔗黑穗病是中国甘蔗生产上最主要的病害,每年造成重大损失.分泌蛋白在真菌侵染寄主植物与获取营养及病理过程起重要作用.本实验室在分析甘蔗黑穗病菌基因组与转录组数据时,发现1个与真菌细胞壁降解有关的β-1,6葡聚糖酶前体的基因Ssa4p.为了揭示Ssa4p对甘蔗黑穗病菌致病性和分泌蛋白组的影响,本研究利用CRISPR/Cas9和T-DNA双元载体所构建的甘蔗黑穗菌基因敲除系统,成功获得了Ssa4p基因的失活突变株.ΔSsa4p突变株(Δ35-Ssa4p)与野生型菌株JG36的配合能力降低且致病性减弱.用iTRAQ方法对Δ35-Ssa4p和野生型菌株的分泌蛋白组进行比较分析,共鉴定到蛋白质1430个,其中上调差异表达蛋白质685个,下调差异表达蛋白质745个.GO功能富集分析及KEGG分析表明,差异蛋白主要定位于无膜细胞器和核糖体,其功能包括参与核糖体、氨基糖和核苷酸糖代谢等生物学过程.本研究发现β-1,6葡聚糖前体影响植物病原真菌的分泌蛋白,加深了对真菌致病性调控机制的认识. 相似文献