1.Antibacterial mechanism of emodin on methicillin staphyloccocusn aureus
Yue BI ; Jiaqi SUI ; Ruihong QIAO ; Mingjie XIE
Chinese Journal of Biochemical Pharmaceutics 2015;(8):27-30
Objective To investigate effect of emodin on cell membrane, protein and nucleic acid synthesis of MRSA41577, and systematically investigate the anti-bacterial mechanism of emodin.Methods TTC assay was used to detected the anti-bacterial activity of emodin on MRSA 41577. Conductivity and macromolecular were detected to investigate the effect of emodin on MRSA41577 cell membrane .SDS-PAGE was used to detect the effect of emodin on the soluble protein synthesis.DAPI staining was used to detect the effect of emodin on nucleic acid synthesis.UV-visible spectrophotometric was used to detected the interaction between emodin and DNA.ResuIts Emodin has significant inhibitory activity on MRSA41577, and the minimum inhibitory concentration was 8μg/mL.After treated with 8 μg/mL emodin for 6h, compared with control group, the macromolecular and conductivity improved (71.48 ±0.026)% (P<0.01) and (2.39 ±0.102)%(P<0.05), sepreatly.Compared with control, after treated with 8μg/ml emodin for 16h,the protein reduced 32.8%, and the contents of DNA and RNA reduced (4.82 ±1.06)%(P<0.05,) and (6.67 ±0.36)%(P<0.053).The UV-visible spectrophotometric results indicated that emodin could integrate with DNA through hydrogen bond.ConcIusion The anti-bacterial mechanism of emodin mainly through damage the cell membrane , inhibit the replication and transcription of DNA through hydrogen bond , inhibit the synthesis of protein, and thus inhibit the biological function of bacteria.
2.Research progress on application of machine learning in quality assurance of intensity-modulated radiotherapy
Jiaqi LI ; Shuming ZHANG ; Hao WANG ; Xile ZHANG ; Jun LI ; Chengyu SHI ; Jing SUI ; Ruijie YANG
Chinese Journal of Radiation Oncology 2019;28(4):309-313
In recent years,the application of machine learning in the field of radiotherapy has been gradually increased along with the development of big data and artificial intelligence technology.Through the training of previous plans,machine learning can predict the results of plan quality and dose verification.It can also predict the multi-leaf collimator (MLC) positioning error and linear accelerator performance.In addition,machine learning can be applied in the quality assurance of intensity-modulated radiotherapy to improve the quality and efficiency of treatment plan and implementation,increase the benefits to the patients and reduce the risk.However,there are many problems,such as difficulty in the selection,extraction and calculation of characteristic value,requirement for large training sample size and insufficient prediction accuracy,which impede its clinical translation and application.In this article,research progress on the application of machine learning in the quality assurance of IMRT was reviewed.
3.Effects of fentanyl on proliferation and apoptosis of H1299 cells by modulating AKT activation
Cheng SUI ; Jinhua CUI ; Yi ZHANG ; Guocheng XUAN ; Jiaqi YAO ; Jing ZHOU
Chinese Journal of Postgraduates of Medicine 2019;42(8):735-739
Objective To explored the effects of fentanyl on cell proliferation of H1299 cells, Methods After treating H1299 cells with different concentrations of fentanyl (0.001, 0.010, 0.100, 1.000 μM) for 12, 24, 48, 72 h, cell viability was detected by CCK-8 assay; the rate of cell apoptosis was determined by DAPI staining; the expression levels of Bax, Bcl-2, p-AKT and AKT protein were measured by Western blotting; Caspase-3 activity was determined by Caspase-3 activity assay kit. Results Compared with the control group, fentanyl obviously inhibited the viability of H1299 cells in a dose and time dependent way. Moreover, treatment with different concentrations of fentanyl(0.001, 0.010, 0.100, 1.000 μM) for 12, 24, 48, 72 h, the apoptosis rate of H1299 cells were significantly increased, The level of Bcl-2 protein reduced the level of Bax protein, and the activity of Caspase-3 in H1299 cells were increased after treatment with fentanyl (0.010, 0.100, 1.000 μM) for 48 h, Furthermore, fentanyl markedly inhibited p-AKT/AKT activity of H1299 cells. Conclusions Fentanyl can inhibit cell proliferation and promote cell apoptosis of human lung cancer, and its mechanism may be related to inhibition of AKT activation ,
4.Application of machine learningin predicting the outcomes and complications of radiotherapy
Shuming ZHANG ; Jiaqi LI ; Hao WANG ; Rongtao JIANG ; Jing SUI ; Chengyu SHI ; Ruijie YANG
Chinese Journal of Radiological Medicine and Protection 2018;38(10):792-795
Machine learning has developed rapidly in recent years.Using machine learning to predict the radiotherapy outcomes and complications can more accurately evaluate the patients' conditions and take appropriate treatment measures as soon as possible.The non-dose and dose related factors generated during radiotherapy are filtered and input into the algorithm model,then corresponding prediction result can be obtained.There are many algorithm models to predict survival rate,tumor control rate and radiotherapy complications,and the predicted result are more accurate now.However,the algorithm model also has various problems,and it needs constant exploration and improvement.
5.Advance of research on endoplasmic reticulum stress and genetic epilepsy.
Xiaohang JIANG ; Yi SUI ; Jiaqi ZHANG ; Tong YI ; Yanyan ZHAO ; Xiaoliang LIU
Chinese Journal of Medical Genetics 2023;40(6):756-761
Epilepsies are a group of chronic neurological disorders characterized by spontaneous recurrent seizures caused by abnormal synchronous firing of neurons and transient brain dysfunction. The underlying mechanisms are complex and not yet fully understood. Endoplasmic reticulum (ER) stress, as a condition of excessive accumulation of unfolded and/or misfolded proteins in the ER lumen, has been considered as a pathophysiological mechanism of epilepsy in recent years. ER stress can enhance the protein processing capacity of the ER to restore protein homeostasis through unfolded protein response, which may inhibit protein translation and promote misfolded protein degradation through the ubiquitin-proteasome system. However, persistent ER stress can also cause neuronal apoptosis and loss, which may aggravate the brain damage and epilepsy. This review has summarized the role of ER stress in the pathogenesis of genetic epilepsy.
Humans
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Endoplasmic Reticulum Stress/genetics*
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Unfolded Protein Response
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Endoplasmic Reticulum/pathology*
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Apoptosis
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Epilepsy/genetics*
6.Study on fentanyl effect in promoting the stemness of breast cancer cell via Wnt3a/β-catenin signaling pathway
Jing ZHOU ; Jinhua CUI ; Yi ZHANG ; Hongfang YANG ; Jiaqi YAO ; Cheng SUI
Chinese Journal of Postgraduates of Medicine 2020;43(7):624-628
Objective:To explore the effect and mechanism of fentanyl on promoting the stemness of breast cancer cell.Methods:From January 2018 to October 2019, human breast cancer cell line BT549 was used as the in vitro research object. Breast cancer cell BT549 was pretreated with 0.01 and 0.10 μmol/L fentanyl. Sphere formation assay and colony formation assay were performed to investigate the role of fentanyl on breast cancer cell stemness. Fluorescent quantitative polymerase chain reaction (FQ-PCR) was used to detect the mRNA level of stemness-related transcription factors gender-determining area Y box protein 2 (Sox2), octamer binding transcription factor 4 (Oct4) and Nanog. Western blotting assay was performed to determine the level of Wnt3a/β-catenin pathway-related markers Wnt3a, phosphorylated glycogen synthase kinase-3β (p-GSK-3β), glycogenase kinase-3β (GSK-3β) and β-catenin. After down-regulating Wnt3a, western blotting assay and sphere formation assay were performed.Results:The sphere diameter, colony formation rate and the expression of Sox2 mRNA, Oct4 mRNA, Nanog mRNA, Wnt3a, p-GSK-3β, GSK-3β and β-catenin in 0.01 and 0.10 μmol/L fentanyl-treated breast cancer cell were significant higher than those in blank control: (131.22 ± 1.06) and (636.37 ± 0.02) μm vs. (72.68 ± 0.13) μm, (41.33 ± 0.03)% and (60.58 ± 1.08)% vs. (20.93 ± 0.15)%, 2.25 ± 0.20 and 3.82 ± 0.84 vs. 1.00, 1.87 ± 1.06 and 3.35 ± 0.04 vs. 1.00, 2.85 ± 0.03 and 4.36 ± 0.50 vs. 1.00, 1.82 ± 0.03 and 2.57 ± 0.42 vs. 1.00, 2.04 ± 0.13 and 2.81 ± 0.05 vs. 1.00, 1.62 ± 0.17 and 2.93 ± 0.06 vs. 1.00, 2.15 ± 0.02 and 3.54 ± 0.21 vs. 1.00, the indexes in 0.10 μmol/L fentanyl-treated breast cancer cell were significantly higher than those in 0.01 μmol/L fentanyl-treated breast cancer cell, and there were statistical differences ( P<0.01). After down-regulating Wnt3a, the expressions of p-GSK-3β, GSK-3β, β-catenin, Sox2, Oct4 and sphere diameter were significantly lower than those in blank control: 0.12 ± 0.05 vs. 1.00, 0.53 ± 0.06 vs. 1.00 and 0.24 ± 0.21 vs. 1.00, 0.28 ± 0.10 vs. 1.00 and 0.06 ± 0.01 vs. 1.00, (18.14 ± 0.30) μm vs. (74.32 ± 0.12) μm, and there were statistical differences ( P<0.01). Conclusions:Fentanyl promotes breast cancer cell stemness by Wnt3a/β-catenin signaling pathway.
7.Protective effect and mechanism of mesenchymal stem cell-derived extracellular vesicle on radiation-induced liver injury
Chi CHEN ; Jiaqi XIAO ; Xin SUI ; Yingcai ZHANG
Organ Transplantation 2023;14(3):411-
Objective To evaluate the protective effect and the underlying mechanism of mesenchymal stem cell-derived extracellular vesicle (MSC-EV) on radiation-induced liver injury and liver cell line injury in mouse models. Methods C57BL/6 mice were randomly divided into the blank group, model group and MSC-EV treatment group (treatment group), with 9 mice in each group. AML12 cells were randomly divided into the control group, irradiation group and MSC-EV intervention group (intervention group). Animal and cell models with radiation-induced injury were established by one-time 15 Gy and 6 Gy X-ray irradiation, respectively. At 48 h after irradiation, liver tissues and serum samples of mice were collected and prepared for subsequent experiments. At 15 h post-irradiation, cell experiment was carried out. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and content of malondialdehyde (MDA) in liver tissues and cells were measured. The relative expression levels of interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β and CXC chemokine ligand (CXCL)10 messenger RNA (mRNA) were detected by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). Liver tissues were prepared for hematoxylin-eosin (HE) staining to calculate liver pathological injury score. The apoptosis of liver tissues and cells was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and propidiumiodide (PI) staining, respectively. The expression levels of glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1) proteins were detected by Western blot. The production level of reactive oxygen species (ROS) was detected by dihydroethidine (DHE) staining. The fluorescence intensity of mitochondrial permeability transition pore (mPTP) was determined. Results Compared with the blank group, serum levels of AST and ALT were up-regulated, and the relative expression levels of IL-1β, TGF-β and CXCL10 mRNA in the mouse liver tissues were up-regulated, and MDA content was increased, liver injury score was elevated, cell apoptosis rate was increased, intracellular ROS level was elevated, and the relative expression levels of GPX4 and FSP1 proteins in the mouse liver tissues were down-regulated in the model group, and the differences were statistically significant (all
8.Structural diversification of bioactive bibenzyls through modular co-culture leading to the discovery of a novel neuroprotective agent.
Yuyu LIU ; Xinnan LI ; Songyang SUI ; Jingshu TANG ; Dawei CHEN ; Yuying KANG ; Kebo XIE ; Jimei LIU ; Jiaqi LAN ; Lei WU ; Ridao CHEN ; Ying PENG ; Jungui DAI
Acta Pharmaceutica Sinica B 2023;13(4):1771-1785
Bibenzyls, a kind of important plant polyphenols, have attracted growing attention for their broad and remarkable pharmacological activities. However, due to the low abundance in nature, uncontrollable and environmentally unfriendly chemical synthesis processes, these compounds are not readily accessible. Herein, one high-yield bibenzyl backbone-producing Escherichia coli strain was constructed by using a highly active and substrate-promiscuous bibenzyl synthase identified from Dendrobium officinale in combination with starter and extender biosynthetic enzymes. Three types of efficiently post-modifying modular strains were engineered by employing methyltransferases, prenyltransferase, and glycosyltransferase with high activity and substrate tolerance together with their corresponding donor biosynthetic modules. Structurally different bibenzyl derivatives were tandemly and/or divergently synthesized by co-culture engineering in various combination modes. Especially, a prenylated bibenzyl derivative ( 12) was found to be an antioxidant that exhibited potent neuroprotective activity in the cellular and rat models of ischemia stroke. RNA-seq, quantitative RT-PCR, and Western-blot analysis demonstrated that 12 could up-regulate the expression level of an apoptosis-inducing factor, mitochondria associated 3 (Aifm3), suggesting that Aifm3 might be a new target in ischemic stroke therapy. This study provides a flexible plug-and-play strategy for the easy-to-implement synthesis of structurally diverse bibenzyls through a modular co-culture engineering pipeline for drug discovery.