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991.
miR-142-3p was reported to be downregulated in acute myelogenous leukemia (AML) and acted as a novel diagnostic marker. However, the regulatory effect of miR-142-3p on drug resistance of AML cells and its underlying mechanism have not been elucidated. Here, we found that miR-142-3p was significantly downregulated and high mobility group box 1 (HMGB1) was dramatically upregulated in AML samples and cells, as well as drug-resistant AML cells. P-gp level and autophagy were markedly enhanced in HL-60/ADR and HL-60/ATRA cells. miR-142-3p overexpression improved drug sensitivity of AML cells by inhibiting cell viability and promoting apoptosis, and inhibited P-gp level and autophagy in drug-resistant AML cells, whereas HMGB1 overexpression obviously reversed these effect. HMGB1 was demonstrated to be a target of miR-142-3p, and miR-142-3p negatively regulated HMGB1 expression. In conclusion, our study elucidated that upregulation of miR-142-3p improves drug sensitivity of AML through reducing P-glycoprotein and repressing autophagy by targeting HMGB1, contributing to better understanding the molecular mechanism of drug resistance in AML. 相似文献
992.
Based on the results of phenotypic features, phylogenetic similarity of 16S rRNA gene sequences and BIOLOG test, a soil bacterium
was identified as Bacillus sp. DM-1. Using either growing cells or a cell-free extract, it transformed parathion and methyl parathion to amino derivatives
by reducing the nitro group. Pesticide transformation by a cell-free extract was specifically inhibited by three nitroreductase
inhibitors, indicating the presence of nitroreductase activity. The nitroreductase activity was NAD(P)H-dependent, O2-insensitive, and exhibited the substrate specificity for parathion and methyl parathion. Reductive transformation significantly
decreased the toxicity of pesticides. 相似文献
993.
994.
Significant Improvement in the Performance of PbSe Quantum Dot Solar Cell by Introducing a CsPbBr3 Perovskite Colloidal Nanocrystal Back Layer 下载免费PDF全文
995.
Zhongmin Hu Minqi Liang Alan Knapp Jianyang Xia Wenping Yuan 《Journal of Plant Ecology》2022,15(4):711
降水-生产力的空间关系是否稳定不变?
降水是全球陆地生态系统中植被生长和净初级生产力的主要驱动因素。因此,探究降水和生产力关系有助于深入了解气候变化如何改变生态系统功能。降水-生产力的空间关系在全球不同草地上非常相似,但在连续多年气候异常的情况下,这种关系是否会发生变化以及如何变化尚不清楚。本研究利用 利用中国北方温带草地长达10年低于多年平均降水的时期,基于遥感植被指数数据,量化了区域尺度上降水-植被生产力关系在持续多年的干湿期之间将如何变化。结果表明,在连续10年的干期,降水-生产力空间相关性急剧下降,而该空间关系的下降主要是由于不同草原类型对干旱的响应在空间上存在高度的异质性,即不同生态系统对干旱的响应程度存在差异。因此,如果未来气候变化进一步加剧全球草地的干旱,那么基于历史时期(平水期)得到的降水-生产力空间关系推测区域尺度植被生产力可能导致误差。 相似文献
996.
Xiao-Lan Gu Wen-Qing Su Chuan-Min Zhou Li-Zhu Fang Ke Zhu Dong-Qiang Ma Fa-Chun Jiang Ze-Min Li Dan Li Shu-Hui Duan Qiu-Ming Peng Rui Wang Yuan Jiang Hui-Ju Han Xue-Jie Yu 《PLoS neglected tropical diseases》2022,16(8)
SFTSV, a tick-borne bunyavirus causing a severe hemorrhagic fever termed as severe fever with thrombocytopenia syndrome (SFTS). To evaluate the potential role of rodents and its ectoparasitic chiggers in the transmission of SFTSV, we collected wild rodents and chiggers on their bodies from a rural area in Qingdao City, Shandong Province, China in September 2020. PCR amplification of the M and L segments of SFTSV showed that 32.3% (10/31) of rodents and 0.2% (1/564) of chiggers (Leptotrombidium deliense) from the rodents were positive to SFTSV. Our results suggested that rodents and chiggers may play an important role in the transmission of SFTSV, although the efficiency of chiggers to transmit SFTSV needs to be further investigated experimentally. 相似文献
997.
Hong Ma Young-Jun Jo Yuan Ma Jin-Tae Hong Byoung-Mog Kwon Ki-Wan Oh 《Phytomedicine》2009,16(4):308-313
This study aimed to investigate the effects of obovatol isolated from Magnolia obovata on pentobarbital-induced sleeping behaviors and to determine whether these effects were mediated by GABAA receptors/chloride channel activation, using a western blot technique and Cl? sensitive fluorescence probe. GABAA receptors subunits expression and chloride influx were investigated in cultured cerebellar granule cells. Obovatol (0.05, 0.1, and 0.2 mg/kg) prolonged the sleeping time induced by pentobarbital (42 mg/kg). In addition, obovatol (20 and 50 μM) significantly increased Cl? influx in the primary cultured cerebellar granule cells. Moreover, obovatol increased the expression of GABAA receptor α-, β-, and γ-subunits. However, it had no effect on the abundance of the expression of glutamic acid decarboxylase (GAD), suggesting that obovatol might not activate GAD. These results suggest that obovatol potentiates pentobarbital-induced sleeping time through the GABAA receptors/chloride channel activation. 相似文献
998.
Overexpression of β-NGF promotes differentiation of bone marrow mesenchymal stem cells into neurons through regulation of AKT and MAPK pathway 总被引:1,自引:0,他引:1
Jun Yuan Guorong Huang Zhe Xiao Lvbiao Lin Tianwang Han 《Molecular and cellular biochemistry》2013,379(1-2):201-211
Bone marrow stromal stem cells (BMSCs) are fibroblastic in shape and capable of self-renewal and have the potential for multi-directional differentiation. Nerve growth factor (NGF), a homodimeric polypeptide, plays an important role in the nervous system by supporting the survival and growth of neural cells, regulating cell growth, promoting differentiation into neuron, and neuron migration. Adenoviral vectors are DNA viruses that contain 36 kb of double-stranded DNA allowing for transmission of the genes to the host nucleus but not inserting them into the host chromosome. The present study aimed to investigate the induction efficiency and differentiation of neural cells from BMSCs by β-NGF gene transfection with recombinant adenoviral vector (Ad-β-NGF) in vitro. The results of immunochemical assay confirmed the induced cells as neuron cells. Moreover, flow cytometric analysis, Annexin-V-FITC/PI, and BrdU assay revealed that chemical inducer β-mercaptoethanol (β-met) triggered apoptosis of BMSCs, as evidenced by inhibition of DNA fragmentation, nuclear condensation, translocation of phospholipid phosphatidylserine, and activation of caspase-3. Furthermore, the results of western blotting showed that β-met suppressed AKT signaling pathway and regulated the MAPKs during differentiation of BMSCs. In contrast, Ad-β-NGF effectively induced the differentiation of BMSCs without causing any cytopathic phenomenon and apoptotic cell death. Moreover, Ad-β-NGF recovered the expression level of phosphorylated AKT and MAPKs in cells exposed to chemical reagents. Taken together, these results suggest that β-NGF gene transfection promotes the differentiation of BMSCs into neurons through regulation of AKT and MAPKs signaling pathways. 相似文献
999.
Chun Xia Liu Wen Long Wang Rui Yuan Zhao Hai Tao Wang Yi Yi Liu Shen Yuan Wang Huan Min Zhou 《In vitro cellular & developmental biology. Animal》2014,50(3):207-213
This study was performed to culture and preliminarily identify the primordial germ cells (PGCs) isolated from the genital ridge of the Mongolian sheep fetus. The growth characteristics of the sheep PGCs were detected in different culture systems such as culture media, resources, and state and passages of feeder cells. The obtained embryonic germ (EG) cells were identified by morphology, enzymology, and immunofluorescence. The results showed that the sheep EG cell colonies were ridgy, typically nest like, and compact, and had regular edges. Alkaline phosphatase staining reaction was weakly positive. EG cells expressed Kit, Rex-1, Nanog, and Oct-4. Immunofluorescence detection was weakly positive for Oct3/4, whereas positive for SSEA-1, SSEA-3, SSEA-4, TRA-1-61, and TRA-1-80. 相似文献
1000.