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41.
Yunfei Bi Qinzheng Zhao Wenkai Yan Mengxue Li Yuxi Liu Chunyan Cheng Lu Zhang Xiaqing Yu Ji Li Chuntao Qian Yufeng Wu Jinfeng Chen Qunfeng Lou 《The Plant journal : for cell and molecular biology》2020,102(1):178-186
Chromosome painting is a powerful technique for chromosome and genome studies. We developed a flexible chromosome painting technique based on multiplex PCR of a synthetic oligonucleotide (oligo) library in cucumber (Cucumis sativus L., 2n = 14). Each oligo in the library was associated with a universal as well as nested specific primers for amplification, which allow the generation of different probes from the same oligo library. We were also able to generate double‐stranded labelled oligos, which produced much stronger signals than single‐stranded labelled oligos, by amplification using fluorophore‐conjugated primer pairs. Oligos covering cucumber chromosome 1 (Chr1) and chromosome 4 (Chr4) consisting of eight segments were synthesized in one library. Different oligo probes generated from the library painted the corresponding chromosomes/segments unambiguously, especially on pachytene chromosomes. This technique was then applied to study the homoeologous relationships among cucumber, C. hystrix and C. melo chromosomes based on cross‐species chromosome painting using Chr4 probes. We demonstrated that the probe was feasible to detect interspecies chromosome homoeologous relationships and chromosomal rearrangement events. Based on its advantages and great convenience, we anticipate that this flexible oligo‐painting technique has great potential for the studies of the structure, organization, and evolution of chromosomes in any species with a sequenced genome. 相似文献
42.
Kai Che Wenkai Han Danxia Li Shuxia Cui Mingxin Zhang Xiaokun Yang Haitao Niu 《Bioscience reports》2021,41(2)
Background: Glycolysis was a representative hallmark in the tumor microenvironment (TME), and we aimed to explore the correlations between glycolysis with immune activity and clinical traits in bladder urothelial carcinoma (BLCA).Methods: Our study obtained glycolysis scores for each BLCA samples from TCGA by a single-sample gene set enrichment analysis (ssGSEA) algorithm, based on a glycolytic gene set. The relationship between glycolysis with prognosis, clinical characteristics, and immune function were investigated subsequently.Results: We found that enhanced glycolysis was associated with poor prognosis and metastasis in BLCA. Moreover, glycolysis had a close correlation with immune function, and enhanced glycolysis increased immune activities. In other words, glycolysis had a positive correlation with immune activities. Immune checkpoints such as IDO1, CD274, were up-regulated in high-glycolysis group as well.Conclusion: We speculated that in BLCA, elevated glycolysis enhanced immune function, which caused tumor cells to overexpress immune checkpoints to evade immune surveillance. Inhibition of glycolysis might be a promising assistant for immunotherapy in bladder cancer. 相似文献
43.
44.
The functional deficiencies of bone marrow-derived mesenchymal stem cells (MSCs) may contribute to the aging process and age-related diseases, such as osteoporosis. Although it has been reported that microRNAs (miRNAs) played an important role in mechanisms of gene regulation of aging, and their expression profiles in MSCs osteogenic differentiation were established in recent years, but it is still elusive for the dynamic patterns of miRNAs in aging process. Importantly, the miRNAs in aged bone tissue had not been yet reported so far. Here, we combined high through-put sequencing with computational techniques to detect miRNAs dynamics in MSCs and bone tissue of age-related osteoporosis. Among the detected miRNAs, 59 identified miRNAs in MSCs and 159 in bone showed significantly differential expressions. And more importantly, there existed 8 up-regulated and 30 down-regulated miRNAs in both MSCs and bone during the aging process, with the majority having a trend of down-regulation. Furthermore, after target prediction and KEGG pathway analysis, we found that their targeted genes were significantly enriched in pathways in cancer, which are complex genetic networks, comprise of a number of age-related pathways. These results strongly suggest that these analyzed miRNAs may be negatively involved in age-related osteoporosis, given that most of them showed a decreased expression, which could lay a good foundation for further functional analysis of these miRNAs in age-related osteoporosis. 相似文献
45.
Wenkai Tian Xin Huang Qingzhong Li Wenzuo Li Jianbo Cheng Baoan Gong 《Journal of molecular modeling》2013,19(3):1311-1318
Quantum chemical calculations have been performed for the complexes Li3OCCX–Y (X?=?Cl, Br, H; Y?=?NH3, H2O, H2S) and Li3OCN–X′Y′ (X′Y′?=?ClF, BrCl, BrF, HF) to study the role of superalkalis in hydrogen and halogen bonds. The results show that the presence of an Li3O cluster in a Lewis acid weakens its acidity, while its presence in a Lewis base enhances its basicity. Furthermore, the latter effect is more prominent than the former one, and the presence of an Na3O cluster causes an even greater effect than Li3O. The strengths of hydrogen and halogen bonds were analyzed using molecular electrostatic potentials. The contributions of superalkalis to the strength of hydrogen and halogen bonds were elucidated by analyzing differences in electron density. 相似文献
46.
Russell T. Shinohara Haochang Shou Marco Carone Robert Schultz Birkan Tunc Drew Parker Melissa Lynne Martin Ragini Verma 《Biometrics》2020,76(1):257-269
The field of neuroimaging dedicated to mapping connections in the brain is increasingly being recognized as key for understanding neurodevelopment and pathology. Networks of these connections are quantitatively represented using complex structures, including matrices, functions, and graphs, which require specialized statistical techniques for estimation and inference about developmental and disorder-related changes. Unfortunately, classical statistical testing procedures are not well suited to high-dimensional testing problems. In the context of global or regional tests for differences in neuroimaging data, traditional analysis of variance (ANOVA) is not directly applicable without first summarizing the data into univariate or low-dimensional features, a process that might mask the salient features of high-dimensional distributions. In this work, we consider a general framework for two-sample testing of complex structures by studying generalized within-group and between-group variances based on distances between complex and potentially high-dimensional observations. We derive an asymptotic approximation to the null distribution of the ANOVA test statistic, and conduct simulation studies with scalar and graph outcomes to study finite sample properties of the test. Finally, we apply our test to our motivating study of structural connectivity in autism spectrum disorder. 相似文献
47.
Ying Liao To Sing Fung Mei Huang Shou Guo Fang Yanxin Zhong Ding Xiang Liu 《Journal of virology》2013,87(14):8124-8134
48.
Ibai Artetxe Christian Sergelius Mayuko Kurita Shou Yamaguchi Shigeo Katsumura J. Peter Slotte Terhi Maula 《Biophysical journal》2013,104(3):604-612
Sphingomyelins (SMs) and ceramides are known to interact favorably in bilayer membranes. Because ceramide lacks a headgroup that could shield its hydrophobic body from unfavorable interactions with water, accommodation of ceramide under the larger phosphocholine headgroup of SM could contribute to their favorable interactions. To elucidate the role of SM headgroup for SM/ceramide interactions, we explored the effects of reducing the size of the phosphocholine headgroup (removing one, two, or three methyls on the choline moiety, or the choline moiety itself). Using differential scanning calorimetry and fluorescence spectroscopy, we found that the size of the SM headgroup had no marked effect on the thermal stability of ordered domains formed by SM analog/palmitoyl ceramide (PCer) interactions. In more complex bilayers composed of a fluid glycerophospholipid, SM analog, and PCer, the thermal stability and molecular order of the laterally segregated gel domains were roughly identical despite variation in SM headgroup size. We suggest that that the association between PCer and SM analogs was stabilized by ceramide’s aversion for disordered phospholipids, by interfacial hydrogen bonding between PCer and the SM analogs, and by attractive van der Waals’ forces between saturated chains of PCer and SM analogs. 相似文献
49.
Jing Lin Xiling Shou Xiaobo Mao Jiangchuan Dong Nilesh Mohabeer Kishan kumar Kushwaha Lei Wang Yousu Su Hongcheng Fang Dazhu Li 《PloS one》2013,8(4)
Background
Macrophage death in advanced lesion has been confirmed to play an important role in plaque instability. However, the mechanism underlying lesion macrophage death still remains largely unknown.Methods and Results
Immunohistochemistry showed that caspase-1 activated in advanced lesion and co-located with macrophages and TUNEL positive reaction. In in-vitro experiments showed that ox-LDL induced caspase-1 activation and this activation was required for ox-LDL induced macrophages lysis, IL-1β and IL-18 production as well as DNA fragmentation. Mechanism experiments showed that CD36 and NLRP3/caspase-1/pathway involved in ox-LDL induced macrophage pyroptosis.Conclusion
Our study here identified a novel cell death, pyroptosis in ox-LDL induced human macrophage, which may be implicated in lesion macrophages death and play an important role in lesion instability. 相似文献50.
Zhongzhao Teng Umar Sadat Wenkai Wang Nasim S. Bahaei Shengyong Chen Victoria E. Young Martin J. Graves Jonathan H. Gillard 《PloS one》2013,8(4)