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991.
Li  Jin  Zhu  Xiaoqiu  Yang  Shangze  Xu  Hui  Guo  Mingyan  Yao  Yiyi  Huang  Zhiquan  Lin  Daowei 《Neurochemical research》2019,44(7):1703-1714

Mitochondrial dysfunction has been proposed to be one of the earliest triggering events in isoflurane-induced neuronal damage. Lidocaine has been demonstrated to attenuate the impairment of cognition in aged rats induced by isoflurane in our previous study. In this study, we hypothesized that lidocaine could attenuate isoflurane anesthesia-induced cognitive impairment by reducing mitochondrial damage. H4 human neuroglioma cells and 18-month-old male Fischer 344 rats were exposed to isoflurane or isoflurane plus lidocaine. Cognitive function was tested at 14 days after treatment by the Barnes Maze test in male Fischer 344 rats. Morphology was observed under electron microscope, and mitochondrial transmembrane potential, electron transfer chain (ETC) enzyme activity, complex-I–IV activity, immunofluorescence and flow cytometry of annexin V-FITC binding, TUNEL assay, and Western blot analyses were applied. Lidocaine attenuated cognitive impairment caused by isoflurane in aged Fischer 344 rat. Lidocaine was effective in reducing mitochondrial damage, mitigating the decrease in mitochondrial membrane potential (ΔΨm), reversing isoflurane-induced changes in complex activity in the mitochondrial electron transfer chain and inhibiting the apoptotic activities induced by isoflurane in H4 cells and Fischer 344 rats. Additionally, lidocaine suppressed the ratio of Bax (the apoptosis-promoting protein) to Bcl-2 (the apoptosis-inhibiting protein) caused by isoflurane in H4 cells. Lidocaine proved effective in attenuating isoflurane-induced POCD by reducing mitochondrial damage.

  相似文献   
992.
Zheng  Yafei  Wu  Yuyun  Liu  Ying  Guo  Zhirui  Bai  Tingting  Zhou  Ping  Wu  Jin  Yang  Qin  Liu  Zhengxia  Lu  Xiang 《Neurochemical research》2019,44(7):1549-1566

This study aimed to investigate the potential effects of gold nanoparticles (Au-NPs) on rat cortical neurons exposed to oxygen–glucose deprivation/reperfusion (OGD/R) and to elucidate the corresponding mechanisms. Primary rat cortical neurons were exposed to OGD/R, which is commonly used in vitro to mimic ischemic injury, and then treated with 5- or 20-nm Au-NPs. We then evaluated cell viability, apoptosis, oxidative stress, and mitochondrial respiration in these neurons. We found that 20-nm Au-NPs increased cell viability, alleviated neuronal apoptosis and oxidative stress, and improved mitochondrial respiration after OGD/R injury, while opposite effects were observed for 5-nm Au-NPs. In terms of the underlying mechanisms, we found that Au-NPs could regulate Akt signaling. Taken together, these results show that 20-nm Au-NPs can protect primary cortical neurons against OGD/R injury, possibly by decreasing apoptosis and oxidative stress, while activating Akt signaling and mitochondrial pathways. Our results suggest that Au-NPs may be potential therapeutic agents for ischemic stroke.

  相似文献   
993.
Jie Liu  Guoxian Yu  Yazhou Ren  Maozu Guo  Jun Wang 《Genomics》2019,111(5):1176-1182
Single nucleotide polymorphism (SNP) interactions can explain the missing heritability of common complex diseases. Many interaction detection methods have been proposed in genome-wide association studies, and they can be divided into two types: population-based and family-based. Compared with population-based methods, family-based methods are robust vs. population stratification. Several family-based methods have been proposed, among which Multifactor Dimensionality Reduction (MDR)-based methods are popular and powerful. However, current MDR-based methods suffer from heavy computational burden. Furthermore, they do not allow for main effect adjustment. In this work we develop a two-stage model-based MDR approach (TrioMDR) to detect multi-locus interaction in trio families (i.e., two parents and one affected child). TrioMDR combines the MDR framework with logistic regression models to check interactions, so TrioMDR can adjust main effects. In addition, unlike consuming permutation procedures used in traditional MDR-based methods, TrioMDR utilizes a simple semi-parameter P-values correction procedure to control type I error rate, this procedure only uses a few permutations to achieve the significance of a multi-locus model and significantly speeds up TrioMDR. We performed extensive experiments on simulated data to compare the type I error and power of TrioMDR under different scenarios. The results demonstrate that TrioMDR is fast and more powerful in general than some recently proposed methods for interaction detection in trios. The R codes of TrioMDR are available at: https://github.com/TrioMDR/TrioMDR.  相似文献   
994.
Paclobutrazol (PBZ) is a kind of chiral pesticide, which is a plant growth regulator and has fungicidal activity. Because of the steric‐hindrance effect, there are two enantiomers (2S, 3S; 2R, 3R) in the production. This research studied on the dissipation behavior of chiral pesticide PBZ in the brine during the Chinese cabbage pickled process by phase column‐high performance liquid chromatography (HPLC). The result demonstrated the PBZ enantiomers had the different dissipation in the brine. The study on the behavior of chiral pesticide PBZ in food may provide more sufficient data and information for understanding the potential risk in food and evaluating the environmental pollution at the enantiomer level.  相似文献   
995.
Doxorubicin (Dox) is an anthracycline antibiotic that has been used to treat different cancers. Dox-induced cardiotoxicity is common in clinical practice, while its mechanism is unknown. It has been proved that lncRNA FOXC2-AS1 may promote doxorubicin resistance and WNT1-inducible signaling pathway protein-1 (WISP1) blocks doxorubicin-induced cardiomyocyte death. Our study aimed to investigate the involvement of lncRNA FOXC2-AS1 and WISP1 in doxorubicin-induced cardiotoxicity and to explore their interactions. In our study we observed that FOXC2-AS1 and WISP1 mRNA were downregulated in heart tissues of mice with Dox-induced cardiotoxicity. FOXC2-AS1 and WISP1 mRNA expression were positively correlated in mice with Dox-induced cardiotoxicity but not in healthy mice. Overexpression of FOXC2-AS1 promoted to viability of mice cardiomyocytes under Dox treatment and also increased the expression level of WISP1. In contrast, WISP1 overexpression showed no significant effect on FOXC2-AS1. We therefore conclude that lncRNA FOXC2-AS1 may upregulate WISP1 to protect cardiomyocytes from doxorubicin-induced cardiotoxicity.  相似文献   
996.
MicroRNAs (miRNAs) are important and ubiquitous regulators of gene expression in eukaryotes. However, the information about miRNAs population and their regulatory functions involving in soybean seed development remains incomplete. Base on the Dicer-like1-mediated cleavage signals during miRNA processing could be employed for novel miRNA discovery, a genome-wide search for miRNA candidates involved in seed development was carried out. As a result, 17 novel miRNAs, 14 isoforms of miRNA (isomiRs) and 31 previously validated miRNAs were discovered. These novel miRNAs and isomiRs represented tissue-specific expression and the isomiRs showed significantly higher abundance than that of their miRNA counterparts in different tissues. After target prediction and degradome sequencing data-based validation, 13 novel miRNA–target pairs were further identified. Besides, five targets of 22-nt iso-gma-miR393h were found to be triggered to produce secondary trans-acting siRNA (ta-siRNAs). Summarily, our results could expand the repertoire of miRNAs with potentially important functions in soybean.  相似文献   
997.
998.
Alternative chemicals to diverse fossil-fuel-based products is urgently needed to mitigate the adverse impacts of fossil fuel depletion on human development. To this end, researchers have focused on the production of biochemical from readily available and affordable waste biomass. This is consistent with current guidelines for sustainable development and provides great advantages related to economy and environment. The search for suitable biochemical products is in progress worldwide. Therefore, this review recommends a biochemical (i.e., medium chain carboxylic acids (MCCAs)) utilizing an emerging biotechnological production platform called the chain elongation (CE) process. This work covers comprehensive introduction of the CE mechanism, functional microbes, available feedstock types and corresponding utilization strategies, major methods to enhance the performance of MCCAs production, and the challenges that need to be addressed for practical application. This work is expected to provide a thorough understanding of the CE technology, to guide and inspire researchers to solve existing problems in depth, and motivate large-scale MCCAs production.  相似文献   
999.
Plant Molecular Biology Reporter - Glycyrrhiza is a widely used traditional Chinese herb with medicinal value. Recently, however, Glycyrrhiza biodiversity has faced an unprecedented threat due to...  相似文献   
1000.
Metformin, a first-line antidiabetic drug, has been reported with anticancer activities in many types of cancer. However, its molecular mechanisms remain largely unknown. As a member of inhibitor of apoptosis proteins, survivin plays an important role in the regulation of cell death. In the present study, we investigated the role of survivin in metformin-induced anticancer activity in non–small cell lung cancer in vitro. Metformin mainly induced apoptotic cell death in A549 and H460 cell lines. It remarkably suppressed the expression of survivin, decreased the stability of this protein, then promoted its proteasomal degradation. Moreover, metformin greatly suppressed protein kinase A (PKA) activity and induced its downstream glycogen synthase kinase 3β (GSK-3β) activation. PKA activators, both 8-Br-cAMP and forskolin, significantly increased the expression of survivin. Consistently both GSK-3β inhibitor LiCl and siRNA restored the expression of survivin in lung cancer cells. Furthermore, metformin induced adenosine 5′-monophosphate-activated protein kinase (AMPK) activation. Suppression of the activity of AMPK with Compound C reversed the degradation of survivin induced by metformin, and meanwhile, restored the activity of PKA and GSK-3β. These results suggest that metformin kills lung cancer cells through AMPK/PKA/GSK-3β-axis–mediated survivin degradation, providing novel insights into the anticancer effects of metformin.  相似文献   
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