在前期FeN/C催化剂研究的基础上,以不同的含硫化合物为硫源,在Ar气氛下高温热处理获得一系列FeNS/C催化剂。使用线性扫描伏安法测试催化剂的氧还原活性,通过热重分析、比表面积和孔径分布测试对催化剂前驱体的热性质及催化剂的结构等进...在前期FeN/C催化剂研究的基础上,以不同的含硫化合物为硫源,在Ar气氛下高温热处理获得一系列FeNS/C催化剂。使用线性扫描伏安法测试催化剂的氧还原活性,通过热重分析、比表面积和孔径分布测试对催化剂前驱体的热性质及催化剂的结构等进行表征。结果表明,分别以硫脲为硫源,1,10-菲啰啉为氮源,FeCl_3为铁源,Black Pearl 2000为载体,催化剂前驱体中硫含量为1wt.%时,所得催化剂比表面积为559. 39 m^2/g,且催化剂表现出较好的氧还原催化活性。硫源的种类、热性质对催化剂的氧还原活性有着明显影响。展开更多
Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim study area, e...Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim study area, erosion by ephemeral streams shortly after the eruption disrupted the lateral continuity of the 270 to 300 cm-thick pumice deposit. Co-evolution of the surface- and ground-water systems in a low-relief, low-slope landscape allowed diffuse groundwater discharge from the banks of the evolving stream system. Accumulation of organic material from groundwater dependent ecosystems at these sites of discharge allowed peat deposits to form on gently sloping erosion surfaces cut into the pumice deposit. Following early stream incision, fine-grained, silt-rich deposits accumulated in valleys and contributed permeability barriers to the lateral migration of water in the pumice aquifer. Fens discharge from the pumice aquifer through gently sloping surfaces patterned after the slope of the erosion surface cut into the pumice deposit and overlain by approximately 1 m of peat on the sloping surface and alluvium or iron-cemented pumice overlain by alluvium at the toe of the slope. The predominant source of groundwater is snowmelt which infiltrates the pumice deposit during the freshet. However, shallow groundwater flow also takes place along permeable pathways in bedrock units. Locally, low volume discharge takes place along faults. The snowmelt-dependent hydrologic system that supports the fens of the Walker Rim study area occurs at elevations primarily above 1585 m.展开更多
Objective:Neuroblastoma(NB)is frequently associated with high-risk pediatric cases that demonstrate limited response to cisplatin,contributing to a poor prognosis.Recent studies have explored the role of tumor cell se...Objective:Neuroblastoma(NB)is frequently associated with high-risk pediatric cases that demonstrate limited response to cisplatin,contributing to a poor prognosis.Recent studies have explored the role of tumor cell senescence in increasing sensitivity to this chemotherapy agent.This study aims to identify genes related to cell senescence in children diagnosed with NB,evaluate their influence on cisplatin sensitivity,and investigate potential strategies to enhance the efficacy of chemotherapy.Methods:Gene expression profiles and clinical data were obtained for 498 NB patients from the GEO database(GSE49710).The study focused on identifying genes that were differentially expressed between stage IV and other stages,particularly those linked to cell senescence and cisplatin resistance.To analyze the prognostic significance of these differentially expressed genes,we employed LASSO regression and multivariate Cox proportional hazards models.Transcriptomic and proteomic analyses of 15 NB specimens revealed a significant correlation between Flap endonuclease-1(FEN1)expression levels and both cellular senescence and sensitivity to cisplatin.We quantified FEN1 expression and cisplatin IC50 values in four different NB cell lines.The influence of FEN1 knockdown and overexpression on NB cell proliferation,invasion,and migration was evaluated using cloning assays,transwell assays,and scratch assays.Furthermore,we utilized Western blotting to analyze senescenceassociated proteins p21 and proliferating cell nuclear antigen(PCNA),thereby evaluating the role of FEN1 in cellular senescence.The impact of FEN1 on cisplatin sensitivity was investigated via the CCK-8 cell counting assay.Additionally,we investigated how FEN1 inhibitors might impact NB cell proliferation and enhance the therapeutic efficacy of cisplatin treatment.Results:FEN1 was found to be highly expressed in stage IV NB and showed a strong association with cisplatin sensitivity,establishing it as a critical molecular marker linked to poor patient prognosis.Notably,elevated FEN1 expression correlated with reduced sensitivity to cisplatin,as evidenced by higher IC50 values.In the SH-SY5Y cell line,FEN1 knockdown led to significant reductions in cell proliferation,invasion,and migration,along with an increase inβ-galactosidase staining—indicative of senescence.This knockdown also resulted in elevated levels of the p21 protein and decreased expression of PCNA,concurrently lowering cisplatin IC50 values.Conversely,FEN1 overexpression in the SK-N-SH cell line resulted in enhanced cell proliferation,invasion,and migration.This overexpression was associated with reducedβ-galactosidase staining,decreased levels of p21,and increased expression of PCNA,ultimately resulting in higher cisplatin IC50 values.Importantly,FEN1 inhibitors alone significantly impeded NB cell proliferation,and their combination with cisplatin further amplified this inhibitory effect compared to cisplatin treatment alone.Conclusions:Bioinformatics and sequencing analyses indicate that the senescence-related gene FEN1 is significantly associated with cisplatin sensitivity and adverse prognosis in pediatric NB.FEN1 plays a pivotal role in regulating NB cell proliferation,invasion,and migration,thereby facilitating cancer progression.Furthermore,it influences cisplatin sensitivity through its effects on cellular senescence.FEN1 inhibitors demonstrate potential both as monotherapies and in conjunction with cisplatin,suggesting that targeting FEN1 may be represent a valuable strategy for improving outcomes in high-risk NB patients.展开更多
Polarization-dependent loss is important to the highly electromagnetic wave absorption(EWA)performance.Recently,metal–Nx moieties have been discovered to trigger polarization loss,but the physical origin and other po...Polarization-dependent loss is important to the highly electromagnetic wave absorption(EWA)performance.Recently,metal–Nx moieties have been discovered to trigger polarization loss,but the physical origin and other possible related loss mechanisms still need to be deeply explored.In this article,we reveal that the FeN_(4)moiety from iron phthalocyanine(FePc)can coordinate with Ti_(3)C_(2)T_(x)through Ti–OH groups,inducing dipole polarization and synchronous magnetic modulation in Fe/TiO_(2)/Ti_(3)C_(2)T_(x)composites.Interestingly,using the enhanced electric dipole moment and increased number of unpaired electrons in Fe atoms,the dipole polarization loss and possible magnetic response can be rapidly confirmed and evaluated.As a result,the minimum reflection loss(RLmin)of Fe/TiO_(2)/Ti_(3)C_(2)T_(x)composites reaches−67.12 dB at 6.72 GHz with a thickness of 3.32 mm.This study elaborates the EWA mechanism based on the atomic scale,and provides a new idea to design efficient EWA materials.展开更多
目的探讨姜黄素(curcumin)对乳腺癌细胞中顺铂(Cisplatin,CDDP)治疗敏感性的影响及其可能机制。方法 CCK-8检测、Hoechst染色观察CDDP、姜黄素单独及联合用药48 h对MCF7细胞增殖抑制和细胞凋亡的影响;Western blot分析MCF7细胞在CDDP(0...目的探讨姜黄素(curcumin)对乳腺癌细胞中顺铂(Cisplatin,CDDP)治疗敏感性的影响及其可能机制。方法 CCK-8检测、Hoechst染色观察CDDP、姜黄素单独及联合用药48 h对MCF7细胞增殖抑制和细胞凋亡的影响;Western blot分析MCF7细胞在CDDP(0、1.25、2.5、5、10、20μg/m L)、姜黄素(0、1、5、20、30、50、100μmol/L)单独及联合处理后FEN1(flap endonuclease 1)表达水平的变化;CCK-8检测沉默FEN1对MCF7细胞中CDDP敏感性的影响。结果 CDDP、姜黄素均可以剂量依赖方式抑制MCF7细胞增殖,其IC50分别为5、30μmol/L;与单独2μg/m L CDDP处理组比较,2μg/m L CDDP联合20μmol/L姜黄素、30μmol/L姜黄素处理组对细胞增殖的抑制效应明显增强[分别为(84.1±0.8)%、(51.1±0.5)%、(29.4±0.3)%,P<0.05];与单独20μmol/L姜黄素处理组比较,20μmol/L姜黄素联合2μg/m L CDDP、5μg/m L CDDP处理组对细胞增殖的抑制效应也明显增强[分别为(76.9±0.7)%、(42.4±0.3)%、(31.6±0.4)%,P<0.05];2μg/m L CDDP联合20μmol/L姜黄素组的细胞凋亡明显增强(P<0.05);与Control siRNA组比较,FEN1 siRNA+CDDP组可显著增强CDDP抑制MCF7细胞增殖的敏感性[(25.4±0.3)%vs(18.7±0.2)%,P<0.05];CDDP增殖抑制无效浓度或低浓度时,FEN1蛋白的表达随CDDP的处理剂量依赖性上调,而姜黄素可剂量依赖性下调FEN1蛋白表达;与单独CDDP和姜黄素处理组比较,2μg/m L CDDP联合20μmol/L姜黄素组可显著降低FEN1蛋白表达(P<0.05)。结论姜黄素可增强CDDP对乳腺癌细胞的敏感性,其机制与降低细胞FEN1的表达有关。展开更多
文摘在前期FeN/C催化剂研究的基础上,以不同的含硫化合物为硫源,在Ar气氛下高温热处理获得一系列FeNS/C催化剂。使用线性扫描伏安法测试催化剂的氧还原活性,通过热重分析、比表面积和孔径分布测试对催化剂前驱体的热性质及催化剂的结构等进行表征。结果表明,分别以硫脲为硫源,1,10-菲啰啉为氮源,FeCl_3为铁源,Black Pearl 2000为载体,催化剂前驱体中硫含量为1wt.%时,所得催化剂比表面积为559. 39 m^2/g,且催化剂表现出较好的氧还原催化活性。硫源的种类、热性质对催化剂的氧还原活性有着明显影响。
文摘Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim study area, erosion by ephemeral streams shortly after the eruption disrupted the lateral continuity of the 270 to 300 cm-thick pumice deposit. Co-evolution of the surface- and ground-water systems in a low-relief, low-slope landscape allowed diffuse groundwater discharge from the banks of the evolving stream system. Accumulation of organic material from groundwater dependent ecosystems at these sites of discharge allowed peat deposits to form on gently sloping erosion surfaces cut into the pumice deposit. Following early stream incision, fine-grained, silt-rich deposits accumulated in valleys and contributed permeability barriers to the lateral migration of water in the pumice aquifer. Fens discharge from the pumice aquifer through gently sloping surfaces patterned after the slope of the erosion surface cut into the pumice deposit and overlain by approximately 1 m of peat on the sloping surface and alluvium or iron-cemented pumice overlain by alluvium at the toe of the slope. The predominant source of groundwater is snowmelt which infiltrates the pumice deposit during the freshet. However, shallow groundwater flow also takes place along permeable pathways in bedrock units. Locally, low volume discharge takes place along faults. The snowmelt-dependent hydrologic system that supports the fens of the Walker Rim study area occurs at elevations primarily above 1585 m.
基金supported by grant from Affiliated Hospital of Nantong University(YJXYY202204)Postgraduate Research&Practice Innovation Program of Jiangsu Province(SJCX24_2063).
文摘Objective:Neuroblastoma(NB)is frequently associated with high-risk pediatric cases that demonstrate limited response to cisplatin,contributing to a poor prognosis.Recent studies have explored the role of tumor cell senescence in increasing sensitivity to this chemotherapy agent.This study aims to identify genes related to cell senescence in children diagnosed with NB,evaluate their influence on cisplatin sensitivity,and investigate potential strategies to enhance the efficacy of chemotherapy.Methods:Gene expression profiles and clinical data were obtained for 498 NB patients from the GEO database(GSE49710).The study focused on identifying genes that were differentially expressed between stage IV and other stages,particularly those linked to cell senescence and cisplatin resistance.To analyze the prognostic significance of these differentially expressed genes,we employed LASSO regression and multivariate Cox proportional hazards models.Transcriptomic and proteomic analyses of 15 NB specimens revealed a significant correlation between Flap endonuclease-1(FEN1)expression levels and both cellular senescence and sensitivity to cisplatin.We quantified FEN1 expression and cisplatin IC50 values in four different NB cell lines.The influence of FEN1 knockdown and overexpression on NB cell proliferation,invasion,and migration was evaluated using cloning assays,transwell assays,and scratch assays.Furthermore,we utilized Western blotting to analyze senescenceassociated proteins p21 and proliferating cell nuclear antigen(PCNA),thereby evaluating the role of FEN1 in cellular senescence.The impact of FEN1 on cisplatin sensitivity was investigated via the CCK-8 cell counting assay.Additionally,we investigated how FEN1 inhibitors might impact NB cell proliferation and enhance the therapeutic efficacy of cisplatin treatment.Results:FEN1 was found to be highly expressed in stage IV NB and showed a strong association with cisplatin sensitivity,establishing it as a critical molecular marker linked to poor patient prognosis.Notably,elevated FEN1 expression correlated with reduced sensitivity to cisplatin,as evidenced by higher IC50 values.In the SH-SY5Y cell line,FEN1 knockdown led to significant reductions in cell proliferation,invasion,and migration,along with an increase inβ-galactosidase staining—indicative of senescence.This knockdown also resulted in elevated levels of the p21 protein and decreased expression of PCNA,concurrently lowering cisplatin IC50 values.Conversely,FEN1 overexpression in the SK-N-SH cell line resulted in enhanced cell proliferation,invasion,and migration.This overexpression was associated with reducedβ-galactosidase staining,decreased levels of p21,and increased expression of PCNA,ultimately resulting in higher cisplatin IC50 values.Importantly,FEN1 inhibitors alone significantly impeded NB cell proliferation,and their combination with cisplatin further amplified this inhibitory effect compared to cisplatin treatment alone.Conclusions:Bioinformatics and sequencing analyses indicate that the senescence-related gene FEN1 is significantly associated with cisplatin sensitivity and adverse prognosis in pediatric NB.FEN1 plays a pivotal role in regulating NB cell proliferation,invasion,and migration,thereby facilitating cancer progression.Furthermore,it influences cisplatin sensitivity through its effects on cellular senescence.FEN1 inhibitors demonstrate potential both as monotherapies and in conjunction with cisplatin,suggesting that targeting FEN1 may be represent a valuable strategy for improving outcomes in high-risk NB patients.
基金supported by the Taishan Young Scholar Program(tsqn202306267)the National Natural Science Foundation of China(51802168)the Natural Science Foundation of Shandong Province(ZR2024ME182,ZR2021ME122)。
文摘Polarization-dependent loss is important to the highly electromagnetic wave absorption(EWA)performance.Recently,metal–Nx moieties have been discovered to trigger polarization loss,but the physical origin and other possible related loss mechanisms still need to be deeply explored.In this article,we reveal that the FeN_(4)moiety from iron phthalocyanine(FePc)can coordinate with Ti_(3)C_(2)T_(x)through Ti–OH groups,inducing dipole polarization and synchronous magnetic modulation in Fe/TiO_(2)/Ti_(3)C_(2)T_(x)composites.Interestingly,using the enhanced electric dipole moment and increased number of unpaired electrons in Fe atoms,the dipole polarization loss and possible magnetic response can be rapidly confirmed and evaluated.As a result,the minimum reflection loss(RLmin)of Fe/TiO_(2)/Ti_(3)C_(2)T_(x)composites reaches−67.12 dB at 6.72 GHz with a thickness of 3.32 mm.This study elaborates the EWA mechanism based on the atomic scale,and provides a new idea to design efficient EWA materials.
文摘目的探讨姜黄素(curcumin)对乳腺癌细胞中顺铂(Cisplatin,CDDP)治疗敏感性的影响及其可能机制。方法 CCK-8检测、Hoechst染色观察CDDP、姜黄素单独及联合用药48 h对MCF7细胞增殖抑制和细胞凋亡的影响;Western blot分析MCF7细胞在CDDP(0、1.25、2.5、5、10、20μg/m L)、姜黄素(0、1、5、20、30、50、100μmol/L)单独及联合处理后FEN1(flap endonuclease 1)表达水平的变化;CCK-8检测沉默FEN1对MCF7细胞中CDDP敏感性的影响。结果 CDDP、姜黄素均可以剂量依赖方式抑制MCF7细胞增殖,其IC50分别为5、30μmol/L;与单独2μg/m L CDDP处理组比较,2μg/m L CDDP联合20μmol/L姜黄素、30μmol/L姜黄素处理组对细胞增殖的抑制效应明显增强[分别为(84.1±0.8)%、(51.1±0.5)%、(29.4±0.3)%,P<0.05];与单独20μmol/L姜黄素处理组比较,20μmol/L姜黄素联合2μg/m L CDDP、5μg/m L CDDP处理组对细胞增殖的抑制效应也明显增强[分别为(76.9±0.7)%、(42.4±0.3)%、(31.6±0.4)%,P<0.05];2μg/m L CDDP联合20μmol/L姜黄素组的细胞凋亡明显增强(P<0.05);与Control siRNA组比较,FEN1 siRNA+CDDP组可显著增强CDDP抑制MCF7细胞增殖的敏感性[(25.4±0.3)%vs(18.7±0.2)%,P<0.05];CDDP增殖抑制无效浓度或低浓度时,FEN1蛋白的表达随CDDP的处理剂量依赖性上调,而姜黄素可剂量依赖性下调FEN1蛋白表达;与单独CDDP和姜黄素处理组比较,2μg/m L CDDP联合20μmol/L姜黄素组可显著降低FEN1蛋白表达(P<0.05)。结论姜黄素可增强CDDP对乳腺癌细胞的敏感性,其机制与降低细胞FEN1的表达有关。
