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烟草特异亚硝胺4-(甲基亚硝胺基)-1-(3-吡啶基)-1-丁酮(NNK)是一种存在于烟草烟气及烟草制品中的强致癌物,其致癌机理是通过细胞色素P450酶的代谢活化生成活泼亲电试剂,导致DNA损伤,因此,建立NNK体外模拟代谢产物的定量分析方法对于研究烟草致癌物具有重要意义。本实验利用高效液相色谱-大气压化学电离串联质谱法(HPLC-APCI-MS/MS)对NNK代谢产物4-羟基-1-(3-吡啶基)-1-丁酮(HPB)进行定量分析。使用选择反应扫描(SRM)模式监测了HPB和内标[3,3,4,4-D4]HPB,分析方法在0.2~400 nmol/L范围内线性关系良好,线性相关系数R2=0.999 9,检出限(LOD)为0.025 nmol/L (S/N=3),定量限(LOQ)为0.05 nmol/L(S/N=10)。方法的日内和日间准确度为96.6%~101.8%,回收率为98.1%~102.6%。所建立的NNK体外模拟代谢模型可用于烟草特异亚硝胺代谢活化分子机制的研究,为定量分析吸烟致癌相关生物标志物奠定基础。  相似文献   

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Peroxiredoxin 1 (PRDX1) participates in tumor cell proliferation, apoptosis, migration, invasion, and the epithelial-to-mesenchymal transition (EMT). This study aimed to investigate the effect of PRDX1 on the EMT of airway epithelial cells stimulated with lipopolysaccharide (LPS) and transforming growth factor-beta 1 (TGF-β1). PRDX1 overexpression significantly increased the proliferation and migration of human bronchial epithelial (BEAS-2B) cells, reduced cell apoptosis (p < 0.01), and induced EMT and collagen deposition by upregulating the expression of the matrix metallopeptidase (MMP)2, MMP9, α-smooth muscle actin (α-SMA), N-cadherin, vimentin and twist proteins and inhibiting E-cadherin expression (p < 0.05). PRDX1 overexpression promoted TGF-β1-mediated inhibition of cell proliferation and migration and significantly enhanced the TGF-β1-induced EMT and collagen synthesis (p < 0.05). Knockdown of PRDX1 inhibited cell proliferation, migration, EMT, and collagen synthesis (p < 0.01), reversed LPS-mediated inhibition of cell proliferation and migration, and significantly suppressed LPS-induced EMT and collagen synthesis (p < 0.01). The result indicating that PRDX1 may be involved in LPS/TGF-1-induced EMT and collagen synthesis in human bronchial epithelial cells.  相似文献   

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基于三相-单相矩阵变换器的串联谐振调制策略   总被引:2,自引:0,他引:2  
蔡家利  张仲超 《机电工程》2007,24(10):43-45
在分析了三相-单相矩阵变换器驱动串联谐振负载基本调制策略的基础上,主要针对如何改善网侧输入电流波形,减少谐波含量,提出了一种全新的改进调制策略,并详细介绍了这两种调制策略的原理.经过仿真试验对比分析,结果表明改进后的调制策略在改善输入电流波形上具有很好的效果,大大降低了谐波含量.  相似文献   

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Background: LncRNA DLX6-AS1 has been uncovered to exert effects on various cancers. Nevertheless, the impacts of DLX6-AS1 on endometrial cancer (EC) development remained obscure. The study explored the influence of DLX6-AS1 on EC progression via the microRNA (miR)-374a-3p/zinc-finger protein (ZFX) axis.Methods: EC cell lines were collected and DLX6-AS1, miR-374a-3p, and ZFX levels in EC cell lines were detected. The EC cells were transfected with DLX6-AS1, miR-374a-3p, and ZFX constructs to examine the biological functions of EC cells. The xenograft model was established for detecting tumor growth. Rescue experiments were conducted to verify the interaction of DLX6-AS1, miR-374a-3p, and ZFX in EC cells.Results: DLX6-AS1 and ZFX levels were elevated, while miR-374a-3p exhibited a reduced level in EC cells. Silencing DLX6-AS1 and elevated miR-374a-3p expressions repressed the biological activities of EC cells. Reduced DLX6-AS1 repressed tumor development. MiR-374a-3p silencing reversed the impacts of DLX6-AS1 silencing, while ZFX overexpression abrogated the impacts of miR-374a-3p elevation on EC cell growth. Mechanically, DLX6-AS1 was found to bind to miR-374a-3p, and miR-374a-3p targeted ZFX.Conclusion: DLX6-AS1 depletion restricts the malignant phenotype of EC cells. The study might provide novel therapeutic biomarkers for EC treatment.  相似文献   

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Traditional Chinese medicine (TCM) has been increasingly employed in the last decades in China for both preventing and treating a variety of cancers. 3-epi-bufotalin is an active ingredient of TCM “Chanpi” with anti-tumor potential. However, the effect and mechanism of 3-epi-bufotalin on colorectal cancers were not well disclosed. The present study demonstrated that 3-epi-bufotalin could reduce viability, trigger apoptosis, and block the cell cycle at the G2/M stage in colorectal cancer cell lines HT29, RKO, and COLO205 in vitro. Moreover, 3-epi-bufotalin inhibited the JAK1/STAT3 signaling pathway. These results indicated the anti-proliferation ability of 3-epi-bufotalin in colorectal cancer cells.  相似文献   

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The pathogenesis of myelodysplastic syndrome (MDS) may be related to the abnormal expression of microRNAs (miRNAs), which could influence the differentiation capacity of mesenchymal stem cells (MSCs) towards adipogenic and osteogenic lineages. In this study, exosomes from bone marrow plasma were successfully extracted and identified. Assessment of miR-103-3p expression in exosomes isolated from BM in 34 MDS patients and 10 controls revealed its 0.52-fold downregulation in patients with MDS compared with controls (NOR) and was downregulated 0.55-fold in MDS-MSCs compared with NOR-MSCs. Transfection of MDS-MSCs with the miR-103-3p mimic improved osteogenic differentiation and decreased adipogenic differentiation in vitro, while inhibition of miR-103-3p showed the opposite results in NOR-MSCs. Thus, the expression of miR-103-3p decreases in MDS BM plasma and MDS-MSCs, significantly impacting MDS-MSCs differentiation. The miR-103-3p mimics may boost MDS-MSCs osteogenic differentiation while weakening lipid differentiation, thereby providing possible target for the treatment of MDS pathogenesis.  相似文献   

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Background: Long-chain non-coding RNA (lncRNA) LINC00609 is a potential tumor suppressor, but the mechanism of action in non-small cell lung cancer (NSCLC) is yet to be understood.Objectives: The effects of LINC00609 on A549 cell proliferation, apoptosis, and cell cycle arrest were investigated. Methods: The LINC00609 levels in NSCLC and normal tissues were analyzed by bioinformatics. Expressions of LINC00609, miR-128-3p, and Rho family GTPase 3 (RND3) in NSCLC cells (A549) were determined by qRT-PCR. Bioinformatics analysis predicted target genes and dual-luciferase reporter assays to ensure that LINC00609 targeted miR-128-3p and miR-128-3p targeted RND3. The proliferation of cells was determined using EDU and CCK-8. Flow cytometry was used to evaluate cell apoptosis rate and cell cycle. The western blotting assay identified proteins related to proliferation and apoptosis. Results: In NSCLC tissues, LINC00609 was expressed in low levels, while its high expression was associated with a higher survival rate. LINC00609 affected cell proliferation, apoptosis, cell cycle arrest, and expression of related proteins. Dual-luciferase reporter assay showed that LINC00609 binds specifically to miR-128-3p, and miR-128-3p binds to RND3. MiR-128-3p overexpression could neutralize the effects of LINC00609. A siRNA targeting RND3 could reverse the effect of the miR-128-3p inhibitor. Silencing RND3 resulted in a decrease in apoptosis rate and the number of cells in the S-phase and an increase in the number of cells in the G1-phase. Furthermore, phosphorylation levels of the AKT protein and mTOR protein, and Bcl2 expression, increased; however, the expression of RND3, Bax, and caspase3 decreased. Conclusions: LINC00609 regulated miR-128-3p/RND3 axis to modulate A549 cell proliferation, apoptosis, and cell cycle arrest. In the case of NSCLC, LINC00609 could be a potential target for therapy.  相似文献   

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The aim of this study is to evaluate the antitumor effect of indirubin‐3‐monoxime and its mode of action in benzo(α)pyrene [B(α)P] induced lung cancer in A/J mice. Light microscopic examination of lung sections of [B(α)P] induced lung cancer mice revealed the presence of adenocarcinoma characterized by extensive proliferation of alveolar epithelium and loss of alveolar spaces. The control lung tissue showed a normal architecture with clear alveolar spaces. Interestingly the indirubin‐3‐monoxime treated groups showed the reduced adenocarcinoma with appearance of alveolar spaces. Transmission Electron Microscopic (TEM) studies of lung sections of [B(α)P] induced lung cancer mice showed the presence of phaemorphic cells with dense granules and increased mitochondria. The lung sections of mice treated with indirubin‐3‐monoxime showed the presence of shrunken, fragmented, and condensed nuclei implying apoptosis. The effects were dose dependent and prominent in 10 mg/kg/5 d/week groups suggesting the therapeutic role of indirubin analogue against this deadly human malignancy. Here, our results indicate that indirubin‐3‐monoxime brings antitumor effect against [B(α)P] induced lung cancer by its apoptotic action in A/J mice. Microsc. Res. Tech. 73:1053–1058, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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介绍IEC61131-3国际标准在火电厂DCS系统中的实际应用。其中以灞桥某电厂的DCS为例,针对3S公司的Codesys编程软件,对IEC61131-3这个工业国际标准进行了详细介绍,同时指出了未来IEC61131-3这个国际标准在DCS系统中应用的重要意义,这也是未来火电厂DCS发展的一种必然趋势。  相似文献   

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Lysophosphatidylcholine acyltransferase 1 (LPCAT1) is a phospholipid acyltransferase that promotes phospholipid synthesis and plasma membrane reconstruction. Exosomes play an important role in tumor metastasis. The release and uptake of exosomes are key steps of their functions and depend on plasma membrane fusion and plasma membrane receptors, respectively. The purpose of this study was to explore whether LPCAT1-induced plasma membrane remodeling would change the secretion and uptake behavior of exosomes in tumor cells. We first confirmed the abnormally high expression of LPCAT1 in colorectal cancer cells by quantitative real-time PCR (qPCR) and Western blot analysis. Then, SW620 cells were used as exosome source cells, and SW480 cells were used as exosome receiver cells. Exosomes from SW620 cells could effectively promote the migration of SW480 cells. When LPCAT1 expression was reduced via siRNA knockdown in the source cells, the secretion of exosomes was downregulated, thus weakening the pro-migratory effects of exosomes on target cells. Conversely, when LPCAT1 was knocked down in target cells, the uptake of exosomes in target cells also decreased sharply. These results undoubtedly revealed that LPCAT1 is functionally associated with the release and internalization of exosomes in colorectal cancer cells and could affect the paracrine effects of exosomes, preliminarily extending the classical metabolic function of LPCAT1 to exosome-related pathways.  相似文献   

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Aim: Gastric cancer (GC) is one of the most common malignant tumors. Chrysophanol has been reported to possess antitumor effects on a variety of cancers; however, its role in GC remains unclear. This study aimed to investigate the effects of chrysophanol on the proliferation, pyroptosis, migration, and invasion of GC cells. Methods: Human GC cell lines MKN 28 and AGS cells were treated with different concentrations of chrysophanol, then cell proliferation, migration, invasion and pyroptosis were determined by CCK-8, colony-forming assay, wound healing assay, Transwell assay, and flow cytometry. Cell migration and invasion were reassessed in these transfected cells following the transfection of nod-like receptor protein-3 (NLRP3) siRNA in MKN 28 and AGS cells. To examine the downstream signaling pathway of the NLRP3 signaling pathway, NLRP3, caspase-1, gasdermin-D, interleukin (IL)-1β, and IL-18 were detected by quantitative real-time-polymerase chain reaction or western blotting. Results: Chrysophanol inhibited the proliferation of GC cells, caused pyroptosis, inhibited cell migration and invasion, and increased the expression of NLRP3 inflammasomes in GC cells. Knockdown of NLRP3 inhibited the effects of chrysophanol on proliferation, pyroptosis, migration, and invasion of GC cells. Chrysophanol plays an anticancer role by enhancing NLRP3. Conclusions: Chrysophanol exerts anti-neoplastic effects in vitro in GC cells by modulating NLRP3, thus highlighting its therapeutic potential in GC.  相似文献   

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X-ray repair cross-complementing protein 1 (XRCC1) could repair cisplatin-induced DNA damage. XRCC1 Arg399Gln and Arg194Trp variants alter XRCC1 expression and function, leading to changes in cancer sensitivity to cisplatin treatment. This study aimed to investigate the effects of XRCC1 Arg399Gln and Arg194Trp polymorphisms on cell viability, apoptosis and XRCC1 expression in cisplatin-sensitive A549 and cisplatin-resistant A549/DDP nonsmall cell lung cancer (NSCLC) cells. Plasmids carrying XRCC1 Arg399Gln and Arg194Trp were constructed and transfected into A549 and A549/DDP cells. RT–PCR, Western blot, MTT assay, and flow cytometry analysis were performed to assess cell viability, apoptosis, and XRCC1 expression. Compared to control cells, the viability of A549 and A549/DDP cells transfected with XRCC1 Arg399Gln and Arg194Trp was higher and the apoptosis rate was lower, and XRCC1 mRNA and protein expression levels were significantly higher. In conclusion, our results suggest that XRCC1 Arg399Gln and Arg194Trp polymorphisms change XRCC1 expression in NSCLC cells and alter the sensitivity of NSCLC to cisplatin-based chemotherapy  相似文献   

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The dispersive-free energy and acid–base forces of 3-n-butyl-6-(1-decyl olefinic acid base)-4-cyclohexene diacid were investigated by inverse gas chromatography. Five nonpolar and 5 polar solvents were used between 353 K and 413 K. By using the retention times of nonpolar and polar probes in the infinite dilution region, adsorption thermodynamic parameters, including the adsorption enthalpy by acid-base interactions and the molar-free adsorption energy of acid-base interaction were evaluated. The results showed that 3-n-butyl-6-(1-decyl olefinic acid base)-4-cyclohexene diacid has low surface energy dispersion and is a Lewis amphoteric material with predominantly basic character. These results were confirmed by the Lewis acidity and basicity constants. Because the surface energy dispersion of inorganic fillers was higher than modified inorganic fillers, and the compatibility of inorganic fillers with the polymers was poor, the inorganic fillers should be modified with 3-n-butyl-6-(1-decyl olefinic acid base)-4-cyclohexene diacid to reduce the surface energy.  相似文献   

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Background: The Warburg effect is considered as a hallmark of various types of cancers, while the regulatory mechanism is poorly understood. Our previous study demonstrated that miR-194-5p directly targets and regulates insulin-like growth factor1 receptor (IGF1R). In this study, we aimed to investigate the role of miR-194-5p in the regulation of the Warburg effect in ovarian cancer cells. Methods: The stable ovarian cell lines with miR-194-5p overexpression or silencing IGF1R expression were established by lentivirus infection. ATP generation, glucose uptake, lactate production and extracellular acidification rate (ECAR) assay were used to analyze the effects of aerobic glycolysis in ovarian cancer cells. Gene expression was analyzed by quantitative polymerase chain reaction (qPCR) and western blot. Immunohistochemistry assays were performed to assess the expression of the IGF1R protein in ovarian cancer tissues. Results: Overexpression of miR-194-5p or silencing IGF1R expression in ovarian cancer cells decreases ATP generation, glucose uptake, lactate production, and ECAR and inhibits both the mRNA and protein expression of PKM2, LDHA, GLUT1, and GLUT3. While the knockdown of miR-194-5p expression led to opposite results. Overexpression of miR-194-5p or silencing IGF1R expression suppressed the phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) pathway, whose activation can sustain aerobic glycolysis in cancer cells, and the knockdown of miR-194-5p expression promoted the activation of the PI3K/AKT pathway. Conclusion: Our results suggest that miR- 194-5p can inhibit the Warburg effect by negative regulation of IGF1R and further repression of the PI3K/AKT pathway, which provides a theoretical basis for further test of miR-194-5p as a target in the treatment of ovarian cancer.  相似文献   

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Triple Negative Breast Cancer (TNBC) immunotherapy has recently shown promising approach. However, some TNBC patients presented with resistance. One of the reasons was attributed to the excessive release of cytokines at the tumor microenvironment (TME) such as Tumor necrosis factor alpha (TNF-α) and Interleukin-10 (IL-10). Fine regulation of these cytokines’ levels via non-coding RNAs (ncRNAs) might alleviate the immune quiescent nature of TME at TNBC tumors. However, the extrapolation of ncRNAs as therapeutic tools is highly challenging. Therefore, disentanglement the nature for the isolation of natural compounds that could modulate the ncRNAs and their respective targets is an applicable translational therapeutic approach. Hence, this study aimed to targeting the chief immune suppressive cytokines at the TME (TNF-α and IL-10) via ncRNAs and to examine the effects of Rosemary aerial parts extract on the expression levels of these ncRNAs in TNBC. Results revealed miR-17-5p as a dual regulator of TNF-α and IL-10. Moreover, an intricate interaction has been shown between miR-17-5p and the oncogenic lncRNAs: MALAT1 and H19. Knocking down of MALAT1 and/or H19 caused an induction in miR-17-5p and reduction in TNF-α and IL-10 expression levels. miR-17-5p was found to be down-regulated, while TNF-α, IL-10, MALAT1 and H19 were up-regulated in BC patients. Forced expression of miR-17-5p in MDA-MB-231 cells reduced TNF-α, IL-10, MALAT1 and H19 expression levels, as well as several BC hallmarks. In a translational approach, ursolic acid (UA) isolated from rosemary induced the expression of miR-17-5p, MALAT1 and decreased H19 expression levels. In conclusion, this study suggests miR-17-5p as a tumor suppressor and an immune-activator miRNA in BC through tuning up the immunological targets TNF-α, IL-10 at the TME and the oncological mediators MALAT1 and H19 lncRNAs.  相似文献   

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为获得高效的阻燃剂,合成了一系列磷酰基丙酰胺类化合物,研究一系列3(O-甲基-O-烷基磷酰基)丙酰胺的电喷雾质谱裂解方式,发现该类化合物的加氢和加钠离子具有不同的裂解方式。加氢裂解的特点是先失去中性NH3碎片和一分子丙烯,最后失去CO;加钠裂解的规律是失去一分子丙烯后,接着失去一分子甲醇。最后根据碎片,提出了可能的裂解途径。  相似文献   

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