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271.
Lee Changsu Song Hye Seon Lee Se Hee Kim Joon Yong Rhee Jin-Kyu Roh Seong Woon 《Archives of microbiology》2021,203(1):261-268
Archives of Microbiology - Extremely halophilic archaea (haloarchaea) belonging to the phylum Euryarchaeota have been found in high-salinity environments. In this study, Halarchaeum sp. CBA1220,... 相似文献
272.
273.
Neurochemical Research - Alzheimer’s disease (AD) is a common neurodegenerative disease associated with deposition of β-amyloid peptide (Aβ). Platycodin D (PLD), a... 相似文献
274.
Jia Song Yao Liu Xuebing Zhang Qiuyue Wu Juan Gao Wei Wang Jin Li Yanling Song Chaoyong Yang 《Nucleic acids research》2021,49(3):e18
Single-cell RNA sequencing enables us to characterize the cellular heterogeneity in single cell resolution with the help of cell type identification algorithms. However, the noise inherent in single-cell RNA-sequencing data severely disturbs the accuracy of cell clustering, marker identification and visualization. We propose that clustering based on feature density profiles can distinguish informative features from noise. We named such strategy as ‘entropy subspace’ separation and designed a cell clustering algorithm called ENtropy subspace separation-based Clustering for nOise REduction (ENCORE) by integrating the ‘entropy subspace’ separation strategy with a consensus clustering method. We demonstrate that ENCORE performs superiorly on cell clustering and generates high-resolution visualization across 12 standard datasets. More importantly, ENCORE enables identification of group markers with biological significance from a hard-to-separate dataset. With the advantages of effective feature selection, improved clustering, accurate marker identification and high-resolution visualization, we present ENCORE to the community as an important tool for scRNA-seq data analysis to study cellular heterogeneity and discover group markers. 相似文献
275.
Binwen Liu Shuaishuai Chu Tiantian Liu Jia Song Zhengliang Ma 《Chronobiology international》2021,38(1):38-45
ABSTRACT The role of the serotonin 7 receptor (5-HT7 receptor) subtype in a number of domains has been widely recognized, but its role in the regulation of changes of the circadian rhythm after anesthesia is still unclear. We used intraperitoneal injection of 5-HT7 receptor agonist LP-211 or antagonist SB-269970 in mice to influence the level of 5-HT7 receptor protein in the SCN and to observe the role of this receptor on circadian rhythm changes after isoflurane anesthesia. Our results show the appropriate dose of SB-269970 significantly alleviated the circadian rhythm disorder induced by isoflurane anesthesia, while LP-211 significantly aggravated it after anesthesia, which is different from the phase shift that can be caused by the administration of LP-211 before anesthesia. These findings may indicate the 5-HT7 receptor plays a complex role in the regulation of circadian rhythm after anesthesia. Our findings may provide some positive significance for alleviating circadian rhythm disorder in patients after anesthesia and ultimately promoting rapid postoperative recovery. 相似文献
276.
277.
Chunyan Luo Decheng Wang Weifeng Huang Yinhong Song Lisha Ge Xinyue Zhang Lixue Yang Jiao Lu Xiancong Tu Qiuyun Chen Jian Yang Chengqi Xu Qing Wang 《生物化学与生物物理学报:疾病的分子基础》2021,1867(7):166130
A high level of low-density lipoprotein cholesterol (LDL) is one of the most important risk factors for coronary artery disease (CAD), the leading cause of death worldwide. However, a low concentration of LDL may be protective. Genome-wide association studies revealed that variation in ADTRP gene increased the risk of CAD. In this study, we found that a low concentration of oxidized-LDL induced the expression of ADTRP. Further analyses showed that knockdown of the expression of LDL receptor genes LDLR, CD36, or LOX-1 significantly downregulated ADTRP expression, whereas overexpression of LDLR/CD36/LOX-1 markedly increased ADTRP expression through the NF-κB pathway. Like ADTRP, LDLR, CD36 and LOX-1 were all involved in endothelial cell (EC) functions relevant to the initiation of atherosclerosis. Downregulation of LDLR/CD36/LOX-1 promoted monocyte adhesion to ECs and transendothelial migration of monocytes by increasing expression of ICAM-1, VCAM-1, E-selectin and P-selectin, decreased EC proliferation and migration, and increased EC apoptosis, thereby promoting the initiation of atherosclerosis. Opposite effects were observed with the overexpression of ADTRP and LDLR/CD36/LOX-1 in ECs. Interestingly, through the NF-κB and AKT pathways, overexpression of ADTRP significantly upregulated the expression of LDLR, CD36, and LOX-1, and knockdown of ADTRP expression significantly downregulated the expression of LDLR, CD36, and LOX-1. These data suggest that ADTRP and LDL receptors LDLR/CD36/LOX-1 positively regulate each other, and form a positive regulatory loop that regulates endothelial cell functions, thereby providing a potential protective mechanism against atherosclerosis. Our findings provide a new molecular mechanism by which deregulation of ADTRP and LDLR/CD36/LOX-1 promote the development of atherosclerosis and CAD. 相似文献
278.
Nagasundarapandian Soundrarajan Cho Hye-sun Prathap Somasundaram Kang Mingue Choi Munjeong Lee Yunjung Jeon Hyoim Song Hyuk Kim Jin-Hoi Park Chankyu 《Amino acids》2021,53(2):313-317
The effects of ΔPb-CATH4, a cathelicidin derived from Python bivittatus, were evaluated against Staphylococcus aureus-infected wounds in mice. These effects were comparable to those of classical antibiotics. ΔPb-CATH4 was resistant to bacterial protease but not to porcine trypsin. A reduction in the level of inflammatory cytokines and an increase in the migration of immune cells was observed in vitro. Thus, ΔPb-CATH4 can promote wound healing by controlling infections including those caused by multidrug-resistant bacteria via its immunomodulatory effects.
相似文献279.
280.
Yanfeng Liu Jingya Yuan Guanghong Jia Wenxue Ye Z. Jeffrey Chen Qingxin Song 《The Plant journal : for cell and molecular biology》2021,105(3):678-690
Bread wheat (Triticum aestivum) is an allohexaploid that was formed via two allopolyploidization events. Growing evidence suggests histone modifications are involved in the response to ‘genomic shock’ and environmental adaptation during polyploid formation and evolution. However, the role of histone modifications, especially histone H3 lysine-27 dimethylation (H3K27me2), in genome evolution remains elusive. Here we analyzed H3K27me2 and H3K27me3 profiles in hexaploid wheat and its tetraploid and diploid relatives. Although H3K27me3 levels were relatively stable among wheat species with different ploidy levels, H3K27me2 intensities increased concurrent with increased ploidy levels, and H3K27me2 peaks were colocalized with massively amplified DTC transposons (CACTA family) in euchromatin, which may silence euchromatic transposons to maintain genome stability during polyploid wheat evolution. Consistently, the distribution of H3K27me2 is mutually exclusive with another repressive histone mark, H3K9me2, that mainly silences transposons in heterochromatic regions. Remarkably, the regions with low H3K27me2 levels (named H3K27me2 valleys) were associated with the formation of DNA double-strand breaks in genomes of wheat, maize (Zea mays) and Arabidopsis. Our results provide a comprehensive view of H3K27me2 and H3K27me3 distributions during wheat evolution, which support roles for H3K27me2 in silencing euchromatic transposons to maintain genome stability and in modifying genetic recombination landscapes. These genomic insights may empower breeding improvement of crops. 相似文献