目的筛选出来自于滤泡性淋巴瘤的转化性弥漫大B细胞淋巴瘤(transforming follicular lymphoma,tFL)与滤泡性淋巴瘤(follicular lymphoma,FL)和弥漫大B细胞淋巴瘤(diffuse large B cell lymphoma,DLBCL)的差异表达基因并进行生物信息学分...目的筛选出来自于滤泡性淋巴瘤的转化性弥漫大B细胞淋巴瘤(transforming follicular lymphoma,tFL)与滤泡性淋巴瘤(follicular lymphoma,FL)和弥漫大B细胞淋巴瘤(diffuse large B cell lymphoma,DLBCL)的差异表达基因并进行生物信息学分析,从而探究它们间的差异以及tFL发展的生物学过程,为后续实验寻找潜在靶点。方法利用GEO数据库筛选出tFL、FL、DLBCL的基因集,分析差异基因,进行GEO富集可视化分析、基因本体(Gene ontology,GO)富集分析、京都基因和基因组数据库(Kyoto Encyclopedia of Genes and Genomes)通路分析。结果tFL与FL的基因集共找到11388个差异表达基因,GO富集分析发现差异基因的功能主要集中在轴突生成、树突发育等;KEGG通路分析发现关键途径为轴突导向、Hippo信号通路等。而tFL与DLBCL共有17216个差异表达基因,GO富集分析差异基因的功能主要集中在调节细胞发育、组蛋白的修饰等;KEGG通路分析发现关键途径为轴突导向、刺激神经组织的配体受体的交互作用等。结论tFL虽然形态学上与DLBCL相似,但从基因表达上看更接近FL。tFL与FL在形态上的差异,是对轴突、树突的发育调节及对细胞成分和细胞发育的调节等多方面共同作用的结果。展开更多
High pressure die casting(HPDC) is a kind of near net shape manufacturing method. However, air entrapment in HPDC parts has serious effects upon the casting quality. In order to reduce the air entrapment defects in a ...High pressure die casting(HPDC) is a kind of near net shape manufacturing method. However, air entrapment in HPDC parts has serious effects upon the casting quality. In order to reduce the air entrapment defects in a AlSi10 MnMg alloy thin-wall longitudinal load-bearing beam produced by HPDC, different gating systems were designed and simulated by software Flow-3D to evaluate the entrapped air. Simulation results showed that when the beam is produced by the original designed gating system with a middle ingate, there exist obvious air entrapments in the critical area; the volume of air entrapment was reduced by replacing the middle ingate to an overflow well, and the filling of molten metal became more stable. When the middle ingate was removed for further improvement, the volume of air entrapment was decreased drastically. The parts with glossy surface and good microstructure have been successfully produced by using the final optimized gating system based on simulation results.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is characterized by dysregulation of the immune microenvironment and the development of chemoresistance.Specifically,expression of the programmed cell death protein 1(PD-1)/prog...BACKGROUND Hepatocellular carcinoma(HCC)is characterized by dysregulation of the immune microenvironment and the development of chemoresistance.Specifically,expression of the programmed cell death protein 1(PD-1)/programmed cell death 1 ligand 1(PD-L1)axis,an immune checkpoint,may lead to tumour immune escape,resulting in disease progression.The latest research shows that tumour immune escape may be caused by the upregulation of PD-L1 mediated by hypoxia-inducible factor-1 alpha(HIF-1α),and simultaneous inhibition of HIF-1αand PD-L1 has the potential to enhance the host’s antitumour immunity.Moreover,inhibition of the PD-1/PD-L1 axis may mitigate tumour chemoresistance.Shuyu pills(SYPs)contain immunity-enhancing and antitumour components,making them a potential HCC treatment.AIM To investigate the efficacy of SYPs for HCC treatment via simultaneous HIF-1α and PD-L1 inhibition and the mechanism involved.METHODS A subcutaneous xenograft tumour model was first established in BALB/c nude mice by the subcutaneous injection of 1×107 SMMC-7721 cells.Male mice(male,5 weeks old;n=24)were then randomly divided into the following four groups(n=6):Control(0.9%normal saline),SYP(200 mg/kg),SYP+cisplatin(DDP)(200 mg/kg+5 mg/kg DDP weekly via intraperitoneal injection),and DDP(5 mg/kg cisplatin weekly via intraperitoneal injection).The dose of saline or SYPs for the indicated mouse groups was 0.2 mL/d via intragastric administration.The tumour volumes and body weights of the mice were measured every 2 d.The mice were euthanized by cervical dislocation after 14 d of continuous treatment,and the xenograft tissues were excised and weighed.Western blot assays were used to measure the protein expression of HIF-1α,PD1,PD-L1,CD4+T cells,and CD8+T cells in HCC tumours from mice.Quantitative reverse transcription polymerase chain reaction was used for real-time quantitative detection of PD-1,PD-L1,and HIF-1α mRNA expression.An immunofluorescence assay was conducted to examine the expression of CD4+T cells and CD8+T cells.RESULTS Compared to mice in the control group,those in the SYP and SYP+DDP groups exhibited reduced tumour volumes and tumour weights.Moreover,the protein and mRNA expression levels of the oncogene HIF1α and that of the negative immunomodulatory factors PD-1 and PD-L1 were decreased in both the SYP and SYP+DDP groups,with the decrease effects being more prominent in the SYP+DDP group than in the SYP group(HIF-1α protein:Control vs SYP,P=0.0129;control vs SYP+DDP,P=0.0004;control vs DDP,P=0.0152,SYP+DDP vs DDP,P=0.0448;HIF-1αmRNA:control vs SYP,P=0.0009;control vs SYP+DDP,P<0.0001;control vs DDP,P=0.0003,SYP vs SYP+DDP,P=0.0192.PD-1 protein:Control vs SYP,P=0.0099;control vs SYP+DDP,P<0.0001,SPY vs SYP+DDP,P=0.0009;SYP+DDP vs DDP,P<0.0001;PD-1 mRNA:control vs SYP,P=0.0002;control vs SYP+DDP,P<0.0001;control vs DDP,P=0.0003,SPY vs SYP+DDP,P=0.0003;SYP+DDP vs DDP,P=0.0002.PD-L1 protein:control vs SYP,P<0.0001;control vs SYP+DDP,P<0.0001;control vs DDP,P<0.0001,SPY vs SYP+DDP,P=0.0040;SYP+DDP vs DDP,P=0.0010;PD-L1 mRNA:Control vs SYP,P<0.0001;control vs SYP+DDP,P<0.0001;control vs DDP,P<0.0001,SPY vs SYP+DDP,P<0.0001;SYP+DDP vs DDP,P=0.0014).Additionally,the quantitative and protein expression levels of CD4+T cells and CD8+T cells were simultaneously upregulated in the SYP+DDP group,whereas only the expression of CD4+T cells was upregulated in the SYP group.(CD4+T cell quantitative:Control vs SYP+DDP,P<0.0001,SYP vs SYP+DDP,P=0.0005;SYP+DDP vs DDP,P=0.0002.CD4+T cell protein:Control vs SYP,P=0.0033;Control vs SYP+DDP,P<0.0001;Control vs DDP,P=0.0021,SYP vs SYP+DDP,P=0.0004;SYP+DDP vs DDP,P=0.0006.Quantitative CD8+T cells:Control vs SYP+DDP,P=0.0013;SYP vs SYP+DDP,P=0.0347;SYP+DDP vs DDP,P=0.0043.CD8+T cell protein:Control vs SYP+DDP,P<0.0001;SYP vs SYP+DDP,P<0.0001;SYP+DDP vs DDP,P<0.0001).Finally,expression of HIF-1αwas positively correlated with that of PD-1/PD-L1 and negatively correlated with the expression of CD4+T cells and CD8+T cells.CONCLUSION SYPs inhibit immune escape and enhance chemosensitization in HCC via simultaneous inhibition of HIF-1α and PD-L1,thus inhibiting the growth of subcutaneous xenograft HCC tumours.展开更多
BACKGROUND The phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin(PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills(XHP) a...BACKGROUND The phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin(PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills(XHP) are a traditional Chinese preparation with antitumour properties. They inhibit the growth of breast cancer, glioma, and other tumours by regulating the PI3K/Akt/mTOR signalling pathway. However, the effects and mechanisms of action of XHP in hepatocellular carcinoma(HCC) remain unclear. Regulation of the PI3K/Akt/mTOR signalling pathway effectively inhibits the progression of HCC. However, no study has focused on the XHPassociated PI3K/Akt/mTOR signalling pathway. Therefore, we hypothesized that XHP might play a role in inhibiting HCC through the PI3K/Akt/mTOR signalling pathway.AIM To confirm the effect of XHP on HCC and the possible mechanisms involved.METHODS The chemical constituents and active components of XHP were analysed using ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry(UPLC-Q-TOF-MS). Cellbased experiments and in vivo xenograft tumour experiments were utilized to evaluate the effect of XHP on HCC tumorigenesis. First, SMMC-7721 cells were incubated with different concentrations of XHP(0, 0.3125, 0.625, 1.25, and 2.5 mg/mL) for 12 h, 24 h and 48 h. Cell viability was assessed using the CCK-8 assay, followed by an assessment of cell migration using a wound healing assay.Second, the effect of XHP on the apoptosis of SMMC-7721 cells was evaluated. SMMC-7721 cells were stained with fluorescein isothiocyanate and annexin V/propidium iodide. The number of apoptotic cells and cell cycle distribution were measured using flow cytometry. The cleaved protein and mRNA expression levels of caspase-3 and caspase-9 were detected using Western blotting and quantitative reverse-transcription polymerase chain reaction(RT-qPCR), respectively.Third, Western blotting and RT–qPCR were performed to confirm the effects of XHP on the protein and mRNA expression of components of the PI3K/Akt/mTOR signalling pathway.Finally, the effects of XHP on the tumorigenesis of subcutaneous hepatocellular tumours in nude mice were assessed.RESULTS The following 12 compounds were identified in XHP using high-resolution mass spectrometry:Valine, 4-gingerol, myrrhone, ricinoleic acid, glycocholic acid, curzerenone, 11-keto-β-boswellic acid, oleic acid, germacrone, 3-acetyl-9,11-dehydro-β-boswellic acid, 5β-androstane-3,17-dione, and 3-acetyl-11-keto-β-boswellic acid. The cell viability assay results showed that treatment with 0.625mg/mL XHP extract decreased HCC cell viability after 12 h, and the effects were dose-and timedependent. The results of the cell scratch assay showed that the migration of HCC cells was significantly inhibited in a time-dependent manner by the administration of XHP extract(0.625mg/mL). Moreover, XHP significantly inhibited cell migration and resulted in cell cycle arrest and apoptosis. Furthermore, XHP downregulated the PI3K/Akt/mTOR signalling pathway, which activated apoptosis executioner proteins(e.g., caspase-9 and caspase-3). The inhibitory effects of XHP on HCC cell growth were determined in vivo by analysing the tumour xenograft volumes and weights.CONCLUSION XHP inhibited HCC cell growth and migration by stimulating apoptosis via the downregulation of the PI3K/Akt/mTOR signalling pathway, followed by the activation of caspase-9 and caspase-3.Our findings clarified that the antitumour effects of XHP on HCC cells are mediated by the PI3K/Akt/mTOR signalling pathway, revealing that XHP may be a potential complementary therapy for HCC.展开更多
Flower-like tungsten disulfide(WS_(2))with a diameter of 5-10μm is prepared by chemical vapor deposition(CVD).Scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),Raman spectroscopy,and ultraviolet-v...Flower-like tungsten disulfide(WS_(2))with a diameter of 5-10μm is prepared by chemical vapor deposition(CVD).Scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),Raman spectroscopy,and ultraviolet-visible(UV-vis)spectroscopy are used to characterize its morphological and optical properties,and its growth mechanism is discussed.The key factors for the formation of flower-like WS_(2)are determined.Firstly,the cooling process causes the generation of nucleation dislocations,and then the"leaf"growth of flower-like WS_(2)is achieved by increasing the temperature.展开更多
Aims Much recent theory has focused on the role of neutral processes in assembling communities,but the basic assumption that all species are demographically identical has found little empirical support.Here,we show th...Aims Much recent theory has focused on the role of neutral processes in assembling communities,but the basic assumption that all species are demographically identical has found little empirical support.Here,we show that the framework of the current neutral theory can easily be generalized to incorporate species differences so long as fitness equivalence among individuals is maintained through trade-offs between birth and death.Methods Our theory development is based on a careful reformulation of the Moran model of metacommunity dynamics in terms of a non-linear one-step stochastic process,which is described by a master equation.Important Findings We demonstrate how fitness equalization through demographic trade-offs can generate significant macroecological diversity patterns,leading to a very different interpretation of the relation between Fisher’s a and Hubbell’s fundamental biodiversity number.Our model shows that equal fitness(not equal demographics)significantly promotes species diversity through strong selective sieving of community membership against high-mortality species,resulting in a positive association between species abundance and per capita death rate.An important implication of demographic trade-off is that it can partly explain the excessively high speciation rates predicted by the neutral theory of the stronger symmetry.Fitness equalization through demographic trade-offs generalizes neutral theory by considering heterospecific demographic difference,thus representing a significant step toward integrating the neutral and niche paradigms of biodiversity.展开更多
Evolution is based on the competition between individuals and therefore rewards only selfish behavior.How cooperation or altruism behavior could prevail in social dilemma then becomes a problematic issue.Game theory o...Evolution is based on the competition between individuals and therefore rewards only selfish behavior.How cooperation or altruism behavior could prevail in social dilemma then becomes a problematic issue.Game theory offers a powerful mathematical approach for studying social behavior.It has been widely used to explain the evolution of cooperation.In this paper,we first introduce related static and dynamic game methods.Then we review two types of mechanisms that can promote cooperation in groups of genetically unrelated individuals,(i)direct reciprocity in repeated games,and(ii)incentive mechanisms such as reward and punishment.展开更多
文摘目的筛选出来自于滤泡性淋巴瘤的转化性弥漫大B细胞淋巴瘤(transforming follicular lymphoma,tFL)与滤泡性淋巴瘤(follicular lymphoma,FL)和弥漫大B细胞淋巴瘤(diffuse large B cell lymphoma,DLBCL)的差异表达基因并进行生物信息学分析,从而探究它们间的差异以及tFL发展的生物学过程,为后续实验寻找潜在靶点。方法利用GEO数据库筛选出tFL、FL、DLBCL的基因集,分析差异基因,进行GEO富集可视化分析、基因本体(Gene ontology,GO)富集分析、京都基因和基因组数据库(Kyoto Encyclopedia of Genes and Genomes)通路分析。结果tFL与FL的基因集共找到11388个差异表达基因,GO富集分析发现差异基因的功能主要集中在轴突生成、树突发育等;KEGG通路分析发现关键途径为轴突导向、Hippo信号通路等。而tFL与DLBCL共有17216个差异表达基因,GO富集分析差异基因的功能主要集中在调节细胞发育、组蛋白的修饰等;KEGG通路分析发现关键途径为轴突导向、刺激神经组织的配体受体的交互作用等。结论tFL虽然形态学上与DLBCL相似,但从基因表达上看更接近FL。tFL与FL在形态上的差异,是对轴突、树突的发育调节及对细胞成分和细胞发育的调节等多方面共同作用的结果。
基金supported by the Major Project of NSFC(51690161)the Student Innovation Program Major Project of Northeastern University(ZD1708)
文摘High pressure die casting(HPDC) is a kind of near net shape manufacturing method. However, air entrapment in HPDC parts has serious effects upon the casting quality. In order to reduce the air entrapment defects in a AlSi10 MnMg alloy thin-wall longitudinal load-bearing beam produced by HPDC, different gating systems were designed and simulated by software Flow-3D to evaluate the entrapped air. Simulation results showed that when the beam is produced by the original designed gating system with a middle ingate, there exist obvious air entrapments in the critical area; the volume of air entrapment was reduced by replacing the middle ingate to an overflow well, and the filling of molten metal became more stable. When the middle ingate was removed for further improvement, the volume of air entrapment was decreased drastically. The parts with glossy surface and good microstructure have been successfully produced by using the final optimized gating system based on simulation results.
基金Supported by National Natural Science Foundation of China,No.U20A20408,and No.82074450Special Natural Science Fund for the Construction of an Innovative Province in Hunan Province,No.S2020JJMSXM1250+1 种基金the Natural Science Foundation of Hunan Province,No.2020JJ4066Hunan Province"domestic first-class cultivation discipline"Integrated Traditional Chinese and Western medicine open fund project,No.2018ZXYJH28 and No.2020ZXYJH35.
文摘BACKGROUND Hepatocellular carcinoma(HCC)is characterized by dysregulation of the immune microenvironment and the development of chemoresistance.Specifically,expression of the programmed cell death protein 1(PD-1)/programmed cell death 1 ligand 1(PD-L1)axis,an immune checkpoint,may lead to tumour immune escape,resulting in disease progression.The latest research shows that tumour immune escape may be caused by the upregulation of PD-L1 mediated by hypoxia-inducible factor-1 alpha(HIF-1α),and simultaneous inhibition of HIF-1αand PD-L1 has the potential to enhance the host’s antitumour immunity.Moreover,inhibition of the PD-1/PD-L1 axis may mitigate tumour chemoresistance.Shuyu pills(SYPs)contain immunity-enhancing and antitumour components,making them a potential HCC treatment.AIM To investigate the efficacy of SYPs for HCC treatment via simultaneous HIF-1α and PD-L1 inhibition and the mechanism involved.METHODS A subcutaneous xenograft tumour model was first established in BALB/c nude mice by the subcutaneous injection of 1×107 SMMC-7721 cells.Male mice(male,5 weeks old;n=24)were then randomly divided into the following four groups(n=6):Control(0.9%normal saline),SYP(200 mg/kg),SYP+cisplatin(DDP)(200 mg/kg+5 mg/kg DDP weekly via intraperitoneal injection),and DDP(5 mg/kg cisplatin weekly via intraperitoneal injection).The dose of saline or SYPs for the indicated mouse groups was 0.2 mL/d via intragastric administration.The tumour volumes and body weights of the mice were measured every 2 d.The mice were euthanized by cervical dislocation after 14 d of continuous treatment,and the xenograft tissues were excised and weighed.Western blot assays were used to measure the protein expression of HIF-1α,PD1,PD-L1,CD4+T cells,and CD8+T cells in HCC tumours from mice.Quantitative reverse transcription polymerase chain reaction was used for real-time quantitative detection of PD-1,PD-L1,and HIF-1α mRNA expression.An immunofluorescence assay was conducted to examine the expression of CD4+T cells and CD8+T cells.RESULTS Compared to mice in the control group,those in the SYP and SYP+DDP groups exhibited reduced tumour volumes and tumour weights.Moreover,the protein and mRNA expression levels of the oncogene HIF1α and that of the negative immunomodulatory factors PD-1 and PD-L1 were decreased in both the SYP and SYP+DDP groups,with the decrease effects being more prominent in the SYP+DDP group than in the SYP group(HIF-1α protein:Control vs SYP,P=0.0129;control vs SYP+DDP,P=0.0004;control vs DDP,P=0.0152,SYP+DDP vs DDP,P=0.0448;HIF-1αmRNA:control vs SYP,P=0.0009;control vs SYP+DDP,P<0.0001;control vs DDP,P=0.0003,SYP vs SYP+DDP,P=0.0192.PD-1 protein:Control vs SYP,P=0.0099;control vs SYP+DDP,P<0.0001,SPY vs SYP+DDP,P=0.0009;SYP+DDP vs DDP,P<0.0001;PD-1 mRNA:control vs SYP,P=0.0002;control vs SYP+DDP,P<0.0001;control vs DDP,P=0.0003,SPY vs SYP+DDP,P=0.0003;SYP+DDP vs DDP,P=0.0002.PD-L1 protein:control vs SYP,P<0.0001;control vs SYP+DDP,P<0.0001;control vs DDP,P<0.0001,SPY vs SYP+DDP,P=0.0040;SYP+DDP vs DDP,P=0.0010;PD-L1 mRNA:Control vs SYP,P<0.0001;control vs SYP+DDP,P<0.0001;control vs DDP,P<0.0001,SPY vs SYP+DDP,P<0.0001;SYP+DDP vs DDP,P=0.0014).Additionally,the quantitative and protein expression levels of CD4+T cells and CD8+T cells were simultaneously upregulated in the SYP+DDP group,whereas only the expression of CD4+T cells was upregulated in the SYP group.(CD4+T cell quantitative:Control vs SYP+DDP,P<0.0001,SYP vs SYP+DDP,P=0.0005;SYP+DDP vs DDP,P=0.0002.CD4+T cell protein:Control vs SYP,P=0.0033;Control vs SYP+DDP,P<0.0001;Control vs DDP,P=0.0021,SYP vs SYP+DDP,P=0.0004;SYP+DDP vs DDP,P=0.0006.Quantitative CD8+T cells:Control vs SYP+DDP,P=0.0013;SYP vs SYP+DDP,P=0.0347;SYP+DDP vs DDP,P=0.0043.CD8+T cell protein:Control vs SYP+DDP,P<0.0001;SYP vs SYP+DDP,P<0.0001;SYP+DDP vs DDP,P<0.0001).Finally,expression of HIF-1αwas positively correlated with that of PD-1/PD-L1 and negatively correlated with the expression of CD4+T cells and CD8+T cells.CONCLUSION SYPs inhibit immune escape and enhance chemosensitization in HCC via simultaneous inhibition of HIF-1α and PD-L1,thus inhibiting the growth of subcutaneous xenograft HCC tumours.
基金Supported by National Natural Science Foundation of China, No. U20A20408 and No. 82074450Natural Science Foundation of Hunan Province, No. 2020JJ4066+4 种基金Hunan Province"Domestic First-class Cultivation Discipline"Integrated Traditional Chinese and Western Medicine Open Fund Project, No. 2020ZXYJH34 and No. 2020ZXYJH35Hunan Graduate Scientific Research Innovation Project, No. QL20210173 and No. CX20210730Hunan Province Science and Technology Innovation Talents Plan College Students Science and Technology Innovation and Entrepreneurship Project, No. 2020RC1004Guangzhou Health Science and Technology Project, No. 20221A011102Hunan Traditional Chinese Medicine Scientific Research Project, No. 202101
文摘BACKGROUND The phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin(PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills(XHP) are a traditional Chinese preparation with antitumour properties. They inhibit the growth of breast cancer, glioma, and other tumours by regulating the PI3K/Akt/mTOR signalling pathway. However, the effects and mechanisms of action of XHP in hepatocellular carcinoma(HCC) remain unclear. Regulation of the PI3K/Akt/mTOR signalling pathway effectively inhibits the progression of HCC. However, no study has focused on the XHPassociated PI3K/Akt/mTOR signalling pathway. Therefore, we hypothesized that XHP might play a role in inhibiting HCC through the PI3K/Akt/mTOR signalling pathway.AIM To confirm the effect of XHP on HCC and the possible mechanisms involved.METHODS The chemical constituents and active components of XHP were analysed using ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry(UPLC-Q-TOF-MS). Cellbased experiments and in vivo xenograft tumour experiments were utilized to evaluate the effect of XHP on HCC tumorigenesis. First, SMMC-7721 cells were incubated with different concentrations of XHP(0, 0.3125, 0.625, 1.25, and 2.5 mg/mL) for 12 h, 24 h and 48 h. Cell viability was assessed using the CCK-8 assay, followed by an assessment of cell migration using a wound healing assay.Second, the effect of XHP on the apoptosis of SMMC-7721 cells was evaluated. SMMC-7721 cells were stained with fluorescein isothiocyanate and annexin V/propidium iodide. The number of apoptotic cells and cell cycle distribution were measured using flow cytometry. The cleaved protein and mRNA expression levels of caspase-3 and caspase-9 were detected using Western blotting and quantitative reverse-transcription polymerase chain reaction(RT-qPCR), respectively.Third, Western blotting and RT–qPCR were performed to confirm the effects of XHP on the protein and mRNA expression of components of the PI3K/Akt/mTOR signalling pathway.Finally, the effects of XHP on the tumorigenesis of subcutaneous hepatocellular tumours in nude mice were assessed.RESULTS The following 12 compounds were identified in XHP using high-resolution mass spectrometry:Valine, 4-gingerol, myrrhone, ricinoleic acid, glycocholic acid, curzerenone, 11-keto-β-boswellic acid, oleic acid, germacrone, 3-acetyl-9,11-dehydro-β-boswellic acid, 5β-androstane-3,17-dione, and 3-acetyl-11-keto-β-boswellic acid. The cell viability assay results showed that treatment with 0.625mg/mL XHP extract decreased HCC cell viability after 12 h, and the effects were dose-and timedependent. The results of the cell scratch assay showed that the migration of HCC cells was significantly inhibited in a time-dependent manner by the administration of XHP extract(0.625mg/mL). Moreover, XHP significantly inhibited cell migration and resulted in cell cycle arrest and apoptosis. Furthermore, XHP downregulated the PI3K/Akt/mTOR signalling pathway, which activated apoptosis executioner proteins(e.g., caspase-9 and caspase-3). The inhibitory effects of XHP on HCC cell growth were determined in vivo by analysing the tumour xenograft volumes and weights.CONCLUSION XHP inhibited HCC cell growth and migration by stimulating apoptosis via the downregulation of the PI3K/Akt/mTOR signalling pathway, followed by the activation of caspase-9 and caspase-3.Our findings clarified that the antitumour effects of XHP on HCC cells are mediated by the PI3K/Akt/mTOR signalling pathway, revealing that XHP may be a potential complementary therapy for HCC.
基金Project supported by the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(Grant No.2020GXLH-Z-029)。
文摘Flower-like tungsten disulfide(WS_(2))with a diameter of 5-10μm is prepared by chemical vapor deposition(CVD).Scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),Raman spectroscopy,and ultraviolet-visible(UV-vis)spectroscopy are used to characterize its morphological and optical properties,and its growth mechanism is discussed.The key factors for the formation of flower-like WS_(2)are determined.Firstly,the cooling process causes the generation of nucleation dislocations,and then the"leaf"growth of flower-like WS_(2)is achieved by increasing the temperature.
基金National Natural Science Foundation of China(31030014,31121003)State Key Basic Research and Development Plan(2007CB106800 and 2010CB434800)+1 种基金Natural Sciences and Engineering Research Council(Canada)University of Alberta International(the China-UofA Joint Research Lab program).
文摘Aims Much recent theory has focused on the role of neutral processes in assembling communities,but the basic assumption that all species are demographically identical has found little empirical support.Here,we show that the framework of the current neutral theory can easily be generalized to incorporate species differences so long as fitness equivalence among individuals is maintained through trade-offs between birth and death.Methods Our theory development is based on a careful reformulation of the Moran model of metacommunity dynamics in terms of a non-linear one-step stochastic process,which is described by a master equation.Important Findings We demonstrate how fitness equalization through demographic trade-offs can generate significant macroecological diversity patterns,leading to a very different interpretation of the relation between Fisher’s a and Hubbell’s fundamental biodiversity number.Our model shows that equal fitness(not equal demographics)significantly promotes species diversity through strong selective sieving of community membership against high-mortality species,resulting in a positive association between species abundance and per capita death rate.An important implication of demographic trade-off is that it can partly explain the excessively high speciation rates predicted by the neutral theory of the stronger symmetry.Fitness equalization through demographic trade-offs generalizes neutral theory by considering heterospecific demographic difference,thus representing a significant step toward integrating the neutral and niche paradigms of biodiversity.
基金This work was supported by the National Natural Science Foundation of China(Nos.71771026 and 71922004)。
文摘Evolution is based on the competition between individuals and therefore rewards only selfish behavior.How cooperation or altruism behavior could prevail in social dilemma then becomes a problematic issue.Game theory offers a powerful mathematical approach for studying social behavior.It has been widely used to explain the evolution of cooperation.In this paper,we first introduce related static and dynamic game methods.Then we review two types of mechanisms that can promote cooperation in groups of genetically unrelated individuals,(i)direct reciprocity in repeated games,and(ii)incentive mechanisms such as reward and punishment.