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971.
972.
Shao  Xiao  Liu  Zhaozheng  Liu  Shanshan  Lin  Na  Deng  Yue 《Molecular and cellular biochemistry》2021,476(4):1783-1795
Molecular and Cellular Biochemistry - Non-coding RNAs (ncRNAs) have shown to act as crucial mediators in atherosclerosis (AS) development. The purpose of our study was to explore the role of...  相似文献   
973.
974.
Lin  Xiaohui  Chen  Hongbin  Chen  Manli  Li  Ting  Lai  Yongxing  Lin  Longzai  Lin  Peiqiang  Liu  Ji  Zhang  Yixian  Chen  Ronghua  Du  Houwei  Jiang  Xinhong  Liu  Nan 《Molecular and cellular biochemistry》2021,476(5):2193-2201

Background: Transplantation of bone marrow-derived mesenchymal stem cells (BMSCs) is a potential therapy for cerebral ischemia. However, the underlying protective mechanism remains undetermined. Here, we tested the hypothesis that transplantation of BMSCs via intravenous injection can alleviate neurological functional deficits through activating PI3K/AKT signaling pathway after cerebral ischemia in rats.

Methods: A cerebral ischemic rat model was established by the 2 h middle cerebral artery occlusion (MCAO). Twenty-four hours later, BMSCs (1?×?106 in 1 ml PBS) from SD rats were injected into the tail vein. Neurological function was evaluated by modified neurological severity score (mNSS) and modified adhesive removal test before and on d1, d3, d7, d10 and d14 after MCAO. Protein expressions of AKT, GSK-3β, CRMP-2 and GAP-43 were detected by Western-bolt. NF-200 was detected by immunofluorescence.

Results: BMSCs transplantation did not only significantly improve the mNSS score and the adhesive-removal somatosensory test after MCAO, but also increase the density of NF-200 and the expression of p-AKT, pGSK-3β and GAP-43, while decrease the expression of pCRMP-2. Meanwhile, these effects can be suppressed by LY294002, a specific inhibitor of PI3K/AKT.

Conclusion: These data suggest that transplantation of BMSCs could promote axon growth and neurological deficit recovery after MCAO, which was associated with activation of PI3K/AKT /GSK-3β/CRMP-2 signaling pathway.

  相似文献   
975.
Jin  Hao  Kim  Hak Sung  Yu  Seung Taek  Shin  Sae Ron  Lee  Sung Hee  Seo  Geom Seog 《Molecular biology reports》2021,48(2):1171-1180
Molecular Biology Reports - A large body of research has demonstrated a synergistic anticancer effect between docosahexaenoic acid (DHA) and standard chemotherapy regimens against colorectal cancer...  相似文献   
976.
977.
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   
978.
Sun  Xiaowen  Shao  Chuang  Chen  Ling  Jin  Xinmeng  Ni  Hong 《Journal of Plant Growth Regulation》2021,40(4):1674-1686

Phosphate-solubilizing bacteria (PSB) are important plant growth-promoting rhizobacteria that can increase soil fertility through the solubilization of insoluble inorganic phosphate and organophosphorus. In this study, a PSB, Burkholderia gladioli MEL01, was isolated and identified from rice–wheat rotation rhizosphere soil. MEL01 had an excellent phosphate-solubilizing capacity (reaching 107.69 mg/L) toward insoluble inorganic phosphate rock phosphate. HPLC analysis revealed that the mechanism of phosphate solubilization of MEL01 was probably due to secreted oxalic acid and gluconic acid transformation of phosphate from insoluble to soluble. MEL01 also exhibited 4030 U/L specific chitosanase activity when cultured with chitosan fermentation medium. Interestingly, the chitosan hydrolysis product chitooligosaccharide could significantly enhance the MEL01 phosphate-solubilizing capacity. Pot experiments showed that MEL01 chitosan medium fermentation liquor (MCMFL) could promote improvement of soil available phosphorus and pakchoi growth when supplemented with phosphate rock phosphate as the phosphate fertilizer. In addition, pot experiments demonstrated that MCMFL could also promote the growth of wheat, which could decrease the amount of compound fertilizer used. Microbial diversity analysis showed that the genera Pseudomonas, Burkholderia, Mycoplana, and Cellvibrio were enriched, which might participate in synergetic phosphate solubilization. Therefore, after fermentation with chitosan and fertilization with rock phosphates, MEL01 has potential as a phosphate biofertilizer in ecological agricultural production.

  相似文献   
979.
Coral Reefs - The Arabian Gulf is a natural laboratory to examine how subtropical coral reef ecosystems might change in responding to recurring heating events because of uniquely high water...  相似文献   
980.
SARS-CoV-2 infects humans through the binding of viral S-protein (spike protein) to human angiotensin I converting enzyme 2 (ACE2). The structure of the ACE2-S-protein complex has been deciphered and we focused on the 27 ACE2 residues that bind to S-protein. From human sequence databases, we identified nine ACE2 variants at ACE2–S-protein binding sites. We used both experimental assays and protein structure analysis to evaluate the effect of each variant on the binding affinity of ACE2 to S-protein. We found one variant causing complete binding disruption, two and three variants, respectively, strongly and mildly reducing the binding affinity, and two variants strongly enhancing the binding affinity. We then collected the ACE2 gene sequences from 57 nonhuman primates. Among the 6 apes and 20 Old World monkeys (OWMs) studied, we found no new variants. In contrast, all 11 New World monkeys (NWMs) studied share four variants each causing a strong reduction in binding affinity, the Philippine tarsier also possesses three such variants, and 18 of the 19 prosimian species studied share one variant causing a strong reduction in binding affinity. Moreover, one OWM and three prosimian variants increased binding affinity by >50%. Based on these findings, we proposed that the common ancestor of primates was strongly resistant to and that of NWMs was completely resistant to SARS-CoV-2 and so is the Philippine tarsier, whereas apes and OWMs, like most humans, are susceptible. This study increases our understanding of the differences in susceptibility to SARS-CoV-2 infection among primates.  相似文献   
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