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81.
Jing Guo Chang-Guo Min Kai-Yan Zhang Cheng-Lin Zhan Yu-Chan Wang Sheng-Kui Hou Xin Ma Wen-Fa Lu 《Molecules (Basel, Switzerland)》2022,27(22)
Tetrabromobisphenol (TBBPA) is the most widely used brominated flame retardant in the world and displays toxicity to humans and animals. However, few studies have focused on its impact on oocyte maturation. Here, TBBPA was added to the culture medium of bovine cumulus–oocyte complexes (COCs) to examine its effect on oocytes. We found that TBBPA exposure displayed an adverse influence on oocyte maturation and subsequent embryonic development. The results of this study showed that TBBPA exposure induced oocyte meiotic failure by disturbing the polar-body extrusion of oocytes and the expansion of cumulus cells. We further found that TBBPA exposure led to defective spindle assembly and chromosome alignment. Meanwhile, TBBPA induced oxidative stress and early apoptosis by mediating the expression of superoxide dismutase 2 (SOD2). TBBPA exposure also caused mitochondrial dysfunction, displaying a decrease in mitochondrial membrane potential, mitochondrial content, mtDNA copy number, and ATP levels, which are regulated by the expression of pyruvate dehydrogenase kinase 3 (PDK3). In addition, the developmental competence of oocytes and the quality of blastocysts were also reduced after TBBPA treatment. These results demonstrated that TBBPA exposure impaired oocyte maturation and developmental competence by disrupting both nuclear and cytoplasmic maturation of the oocyte, which might have been caused by oxidative stress induced by mitochondrial dysfunction. 相似文献
82.
Xiu-Jun Xu Mei-Ling Zhang Yan-Min Hou Ke Zhang Da-Hong Yao Guo-Yu Li Wei-Bing Kou Hang-Yu Wang Jin-Hui Wang 《Molecules (Basel, Switzerland)》2022,27(20)
The clinical application of gentamicin may lead to acute kidney injury (AKI), and the nephrotoxicity of gentamicin is related to the pathological mechanism of several oxidative and inflammatory cytokines. Plant-derived essential oils have good anti-inflammatory and antioxidant properties. This study aimed to clarify the protective effect of Amomum tsao-ko essential oils (AOs) on gentamicin-induced AKI in rats and its possible mechanism. The rat AKI model was induced by intraperitoneal injection of gentamicin. After 14 days of oral AO treatment, the renal function and pathological changes of the kidney tissues were evaluated, and the level of kidney tissue oxidative stress was detected. The content of inflammatory cytokines was measured by ELISA. The expression of ERK1/2, JNK1/2, p38, NF-κB, caspase-3, and Bax/Bcl-2 proteins were estimated by Western blot analysis. The results showed that taking AO reduced the contents of serum urea and creatinine in AKI rats and improve the pathological changes and oxidative stress of the kidney tissue in rats. At the same time, AO reduced inflammation and apoptosis during AKI by regulating the MAPK pathway. The data show that AO has a protective effect on the kidneys and may be a potential drug for treating kidney injury. 相似文献
83.
Zhenzhen Guo Luyao Sun Haojie Xia Shibin Tian Mengyue Liu Jiejie Hou Jiahuan Li Haihong Lin Gangjun Du 《Molecules (Basel, Switzerland)》2022,27(23)
This study aims to observe the differentiating effect of shikonin on Wilms’ tumor 1 (WT1)-positive HL-60 cells and investigate the fate of the differentiated leukemia cells. WT1 overexpression unaffected cell viability but promoted resistance to H2O2-induced DNA injury and cell apoptosis. The binding of shikonin to the WT1 protein was confirmed by molecular docking and drug affinity reaction target stability (DARTS). Shikonin at the non-cytotoxic concentration could decrease the WT1 protein and simultaneously reduced the CD34 protein and increased the CD11b protein in a dose-dependent manner in normal HL-60 cells but not in WT1-overexpressed HL-60 cells. Shikonin unaffected HL-60 cell viability in 48 h. However, it lasted for 10 days; could attenuate cell proliferation, mitochondrial membrane potential (MMP), and self-renewal; prevent the cell cycle; promote cell apoptosis. In a mouse leukemia model, shikonin could decrease the WT1 protein to prevent leukemia development in a dose-dependent manner. In this study, we also confirmed preliminarily the protein–protein interactions between WT1 and CD34 in molecular docking and CO-IP assay. Our results suggest that: 1. shikonin can down-regulate the WT1 protein level for leukemia differentiation therapy, and 2. the interaction between WT1 and CD34 proteins may be responsible for granulocyte/monocyte immaturity in HL-60 cells. 相似文献
84.
Min Yang Chih-Yao Hou Hsien-Yi Hsu Sulfath Hakkim Hazeena Shella Permatasari Santoso Cheng-Chia Yu Chao-Kai Chang Mohsen Gavahian Chang-Wei Hsieh 《Molecules (Basel, Switzerland)》2022,27(23)
Pickled radish (Raphanus sativus) is a traditional Asian ingredient, but the traditional method takes decades to make this product. To optimize such a process, this study compared the saponin content of pickled radishes with different thermal processing and traditional processes (production time of 7 days, 10 years, and 20 years) and evaluated the effects of different thermal processes on the formation of radish saponin through kinetics study and mass spectrometry. The results showed that increasing the pickling time enhanced the formation of saponin in commercial pickled radishes (25 °C, 7 days, 6.50 ± 1.46 mg g−1; 3650 days, 23.11 ± 1.22 mg g−1), but these increases were lower than those induced by thermal processing (70 °C 30 days 24.24 ± 1.01 mg g−1). However, it was found that the pickling time of more than 10 years and the processing temperature of more than 80 °C reduce the saponin content. Liquid chromatography–mass spectrometry (LC-MS) analysis showed that the major saponin in untreated radish was Tupistroside G, whereas treated samples contained Asparagoside A and Timosaponin A1. Moreover, this study elucidated the chemical structure of saponins in TPR. The findings indicated that thermal treatment could induce functional saponin conversion in plants, and such a mechanism can also be used to improve the health efficacy of plant-based crops. 相似文献
85.
Hui-E Zhang Meng-Yao Chu Tao Jiang Xin-Hong Song Jian-Feng Hou Li-Ye Cheng Ye Feng Chang-Bao Chen En-Peng Wang 《Molecules (Basel, Switzerland)》2022,27(23)
Red ginseng (RG), which is obtained from heated Panax ginseng and is produced by steaming followed by drying, is a valuable herb in Asian countries. Steamed ginseng dew (SGD) is a by-product produced in processing red ginseng. In the present study, phytochemical profiling of extracts of red ginseng and steamed ginseng dew was carried out using gas chromatography-mass spectrometry (GC-MS) and rapid resolution liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (RRLC-Q-TOF-MS) analysis. Additionally, antioxidant activities (DPPH, ·OH, and ABTS scavenging ability) and whitening activities (tyrosinase and elastase inhibitory activity) were analyzed. Phytochemical profiling revealed the presence of 66 and 28 compounds that were non-saponin components in chloroform extracts of red ginseng and steamed ginseng dew (RG-CE and SGD-CE), respectively. Meanwhile, there were 20 ginsenosides identified in n-butanol extracts of red ginseng and steamed ginseng dew (RG-NBE and SGD-NBE). By comparing the different polar extracts of red ginseng and steamed ginseng dew, it was found that the ethyl acetate extract of red ginseng (RG-EAE) had the best antioxidant capacity and whitening effect, the water extract of steamed ginseng dew (SGD-WE) had stronger antioxidant capacity, and the SGD-NBE and SGD-CE had a better whitening effect. This study shows that RG and SGD have tremendous potential to be used in the cosmetic industries. 相似文献
86.
Xiaoyan Guo Lu Yao Xiangyan Hou Xiaofeng Wu Yaowen Zhang Qian Zhu Zhangtao Guo Shuting Li Yilan Jiang Shouhua Feng Keke Huang 《Chemical science》2022,13(32):9440
Exsolution is an ingenious strategy for the in situ construction of metal- or alloy-decorated oxides and, due to its promising energy related catalysis applications, has advanced from use in perovskites to use in spinels. Despite its great importance for designing target composites, the ability to identify whether active metal ions at octahedral or tetrahedral sites will preferentially exsolve in a spinel remains unexplored. Here, an inverse spinel NiFe2O4 (NFO) was employed as a prototype and FeNi/NFO composites were successfully constructed via exsolution. The preferential breaking of octahedral metal–oxygen bonds in the spinel oxide was directly observed using Mössbauer and X-ray absorption spectroscopy. This was further verified from the negative segregation energies calculated based on density-functional theory. One exsolved FeNi/NFO composite exhibits enhanced electrochemical activity with an overpotential of 283 mV at 10 mA cm−2 and a long stability time for the oxygen evolution reaction. This work offers a unique insight into spinel exsolution based on the preferential breaking of chemical bonds and may be an effective guide for the design of new composite catalysts where the desired metal ions are deliberately introduced to octahedral and/or tetrahedral sites.The preferential breaking of octahedral metal–oxygen bonds is exploited to construct an exsolved FeNi/NFO composite for an efficient oxygen evolution reaction. 相似文献
87.
<正>1引言设H是Hilbert空间,B(H)是H上有界线性算子全体生成的Banach代数.设A ∈B(H),用A*,R(A)和N(A)分别表示A的自伴算子,A的值域和A的核空间.用L(H)={P∈B(H):P=P2}表示H上所有幂等算子组成的集合.当P2=P=P*时,称幂等算子P为正交投影.设M是Hilbert空间H的闭子空间,用PM表示值域为M的正交投影.满足算子方程(Ⅰ)ASA=A的算子S称为算子A的内逆A-,满足(Ⅱ)SAS=S的S称为A的外逆. 相似文献
88.
A key element for reducing energy consumption and improving thermal comfort on high-speed rail is controlling air-conditioning temperature. Accurate prediction of air supply temperature is aimed at improving control effects. Existing studies of supply air temperature prediction models are interdisciplinary, involving heat transfer science and computer science, where the problem is defined as time-series prediction. However, the model is widely accepted as a complex model that is nonlinear and dynamic. That makes it difficult for existing statistical and deep learning methods, e.g., autoregressive integrated moving average model (ARIMA), convolutional neural network (CNN), and long short-term memory network (LSTM), to fully capture the interaction between these variables and provide accurate prediction results. Recent studies have shown the potential of the Transformer to increase the prediction capacity. This paper offers an improved temporal fusion transformers (TFT) prediction model for supply air temperature in high-speed train carriages to tackle these challenges, with two improvements: (i) Double-convolutional residual encoder structure based on dilated causal convolution; (ii) Spatio-temporal double-gated structure based on Gated Linear Units. Moreover, this study designs a loss function suitable for general long sequence time-series forecast tasks for temperature forecasting. Empirical simulations using a high-speed rail air-conditioning operation dataset at a specific location in China show that the temperature prediction of the two units using the improved TFT model improves the MAPE by 21.70% and 11.73%, respectively the original model. Furthermore, experiments demonstrate that the model effectively outperforms seven popular methods on time series computing tasks, and the attention of the prediction problem in the time dimension is analyzed. 相似文献
89.
Xiao-Xue Jing Da-Qing Li Yong Zhang Xiang-Yu Hou Jie Jiang Xing-Ce Fan Meng-Chen Wang Shao-Peng Feng Yuan-fang Yu Jun-Peng Lu Zhen-Liang Hu Zhen-Hua Ni 《中国物理快报》2021,(7):65-75
Two-dimensional surface-enhanced Raman scattering(SERS) substrates have drawn intense attention due to their excellent spectral reproducibility, high uniformity and perfect anti-interference ability. However, the inferior detection sensitivity and low enhancement have limited the practical application of two-dimensional SERS substrates. To address this issue, we propose that the interaction between the MoTe_2 substrate and the analyte rhodamine 6 G molecules could be remarkably enhanced by the introduced p-doping effect and lattice distortion of MoTe_2 via hydrogen plasma treatment. After the treatment, the SERS is greatly improved, the enhancement factor of probe molecules reaches 1.83 × 10~6 as well as the limit of detection concentration reaches 10-13 M.This method is anticipated to afford new enhancement probability for other 2D materials, even non-metal oxide semiconductor SERS substrates. 相似文献
90.