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991.
A new species of rugose coral, Sanidophyllum dubium n. sp., and the typical Emsian (Early Devonian) rugose coral Xystriphylloides nobilis are described from the Mia Le Formation in northern Vietnam. The lower Emsian index conodonts ranging from the Polygnathus excavatus zone to the P. nothoperbonus zone are illustrated. The biostratigraphic correlation between northern Vietnam and South China shows that the Mia Le Formation in northern Vietnam is early Emsian in age, and its upper part can be correlated with the lower part of the Shizhou Member of the Yukiang Formation in Liujing, Guangxi and its equivalents in South China. Based on the study of the lower Emsian biostratigraphic sequence, the disappearance of Xystriphylloides nobilis fauna in the overlying bed of the uppermost Mia Le Formation and the extinction of the “tonkinensis fauna” (sensu lato) in the interval between the basal Si Phai Formation and the uppermost Mia Le Formation demonstrate the influence of the Yujiang Event in northern Vietnam. 相似文献
992.
Duckweed (Lemnaceae) is a fast‐growing aquatic vascular plant. It has drawn an increasing attention worldwide due to its application in value‐added nutritional products and in sewage disposal. In particular, duckweed is a promising feedstock for bioenergy production. In this review, we summarized applications of duckweed from the following four aspects. Firstly, duckweed could utilize nitrogen, phosphorus, and inorganic nutrition in wastewater and reduces water eutrophication efficiently. During these processes, microorganisms play an important role in promoting duckweed growth and improving its tolerance to stresses. We also introduced our pilot‐scale test using duckweed for wastewater treatment and biomass production simultaneously. Secondly, its capability of fast accumulation of large amounts of starch makes duckweed a promising bioenergy feedstock, catering the currently increasing demand for bioethanol production. Pretreatment conditions prior to fermentation can be optimized to improve the conversion efficiency from starch to bioethanol. Furthermore, duckweed serves as an ideal source for food supply or animal feed because the composition of amino acids in duckweed is similar to that of whey protein, which is easily digested and assimilated by human and other animals. Finally, severing as a natural plant factory, duckweed has shown great potential in the production of pharmaceuticals and dietary supplements. With the surge of omics data and the development of Clustered Regularly Interspaced Short Palindromic Repeats technology, remodeling of the metabolic pathway in duckweed for synthetic biology study will be attainable in the future. 相似文献
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Guangming Li Dejun Kong Yafei Qin Hongda Wang Yonghao Hu Yiming Zhao Jingpeng Hao Hong Qin Dingding Yu Yanglin Zhu Chenglu Sun Hao Wang 《Cytotherapy》2021,23(7):617-626
Background aimsMesenchymal stromal cells and immunosuppressive factor IL-37 can both suppress concanavalin A (Con A)-induced hepatitis in mice. Endometrial regenerative cells (ERCs), novel types of mesenchymal-like stromal cells, possess powerful immunomodulatory effects and are effective in treating various diseases. The aim of this study was to explore the effects of ERCs in suppressing Con A-induced hepatitis and determine whether IL-37 overexpression could enhance the therapeutic effect of ERCs in this process.MethodsERCs were extracted from the menstrual blood of healthy female volunteer donors. The IL-37 gene was transferred into ERCs, and the expression of IL-37 in cells was detected by western blot and enzyme-linked immunosorbent assay. Hepatitis was induced by Con A in C57BL/6 mice that were randomly divided into groups treated with phosphate-buffered saline, ERCs, IL-37 or ERCs transfected with the IL-37 gene (IL-37-ERCs). Cell tracking, liver function, histopathological and immunohistological changes, immune cell proportions and levels of cytokines were measured 24 h after Con A administration.ResultsCompared with ERC or IL-37 treatment, IL-37-ERCs further reduced levels of liver enzymes (alanine aminotransferase and aspartate aminotransferase) and improved histopathological changes in the liver. In addition, IL-37-ERC treatment further reduced the proportions of M1 macrophages and CD4+ T cells and increased the proportion of regulatory T cells. Moreover, IL-37-ERC treatment resulted in lower levels of IL-12 and interferon gamma, and higher level of transforming growth factor beta.ConclusionsThe results of this study suggest that ERCs can effectively alleviate Con A-induced hepatitis. Furthermore, IL-37 overexpression can significantly enhance the therapeutic efficacy of ERCs by augmenting the immunomodulatory and anti-inflammatory properties of ERCs. This study may provide a promising strategy for treatment of T-cell-dependent hepatitis. 相似文献
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Xu Han Yun Long Yu Duo Ma Zhao Yan Zhang Xin Hua Liu 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):345
Based on previous studies, 66 2-phenyl-4H-chromone derivatives containing amide and 1,3,4-oxadiazole moieties were prepared as potential telomerase inhibitors. The results showed most of the title compounds exhibited significantly inhibitory activity on telomerase. Among them, some compounds demonstrated the most potent telomerase inhibitory activity (IC50 < 1 µM), which was significantly superior to the staurosporine (IC50 = 6.41 µM). In addition, clear structure–activity relationships were summarised, indicating that the substitution of the methoxy group and the position, type and number of the substituents on the phenyl ring had significant effects on telomerase activity. Among them, compound A33 showed considerable inhibition against telomerase. Flow cytometric analysis showed that compound A33 could arrest MGC-803 cell cycle at G2/M phase and induce apoptosis in a concentration-dependent way. Meanwhile, Western blotting revealed that this compound could reduce the expression of dyskerin, which is a fragment of telomerase. 相似文献
999.
Xi Liu Feng Jiang Zhilinag Wang Lang Tang Bin Zou Pengfei Xu Tenghua Yu 《Journal of cellular and molecular medicine》2021,25(1):96-109
Lung cancer is the most aggressive tumour afflicting patients on a global scale. Extracellular vesicle (EV)-delivered microRNAs (miRs) have been reported to play critical roles in cancer development. The current study aimed to investigate the role of hypoxic bone marrow mesenchymal cell (BMSC)-derived EVs containing miR-328-3p in lung cancer. miR-328-3p expression was determined in a set of lung cancer tissues by RT-qPCR. BMSCs were infected with lentivirus-mediated miR-328-3p knock-down and then cultured in normoxic or hypoxic conditions, followed by isolation of EVs. Following ectopic expression and depletion experiments in lung cancer cells, the biological functions of miR-328-3p were analysed using CCK-8 assay, flow cytometry and Transwell assay. Xenograft in nude mice was performed to test the in vivo effects of miR-328-3p delivered by hypoxic BMSC-derived EVs on tumour growth of lung cancer. Finally, the expression of circulating miR-328-3p was detected in the serum of lung cancer patients. miR-328-3p was highly expressed in EVs derived from hypoxic BMSCs. miR-328-3p was delivered to lung cancer cells by hypoxic BMSC-derived EVs, thereby promoting lung cancer cell proliferation, invasion, migration and epithelial-mesenchymal transition. miR-328-3p targeted NF2 to inactivate the Hippo pathway. Moreover, EV-delivered miR-328-3p increased tumour growth in vivo. Additionally, circulating miR-328-3p was bioactive in the serum of lung cancer patients. Taken together, our results demonstrated that hypoxic BMSC-derived EVs could deliver miR-328-3p to lung cancer cells and that miR-328-3p targets the NF2 gene, thereby inhibiting the Hippo pathway to ultimately promote the occurrence and progression of lung cancer. 相似文献
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Zhuyun Qin Shixuan Shen Kaiyong Qu Yu Nie Haitao Zhang 《Journal of cellular and molecular medicine》2021,25(13):6448-6454
Myocardial ischemia-reperfusion injury (MIRI) with concurrent severe sepsis has led to substantial mortality. Mild hypothermia (MHT) has been proved to have a therapeutic effect in either MIRI or severe sepsis, which suggests it might be beneficial for MIRI complicating severe sepsis. In this study, Sprague-Dawley rats with MIRI complicating severe sepsis were allotted in either MHT (33 ± 0.5°C) group or normothermia (NT, 37 ± 0.5°C) group; as control, rats receiving sham surgery and normal saline were kept at NT. After 2h of temperature maintenance, blood and heart tissue were acquired for detections. Lactate dehydrogenase (LDH) and MB isoenzyme of creatine kinase (CK-MB) in blood, triphenyl tetrazolium chloride and Evans blue staining, hematoxylin and eosin staining for myocardium were employed to detect myocardial damage. Tumor necrosis factor (TNF)-α and caspase-3 was performed by immunohistochemistry to exam myocardial inflammation and apoptosis. Detection of NADPH oxidase (NOX) 2 was for myocardial oxidative stress. In MHT group, systolic blood pressure was improved significantly compared with NT group. Myocardial infarct size, morphological change, LDH and CK-MB levels were attenuated compared to NT group. Moreover, less expressions of TNF-α, caspase-3 and NOX2 in MHT group were presented compared with NT group. MHT showed cardioprotection by improving cardiac dysfunction, reducing myocardial infarct size and attenuating myocardial injury, inflammation, apoptosis and oxidative stress. 相似文献