Phenolic resins are widely used in thermal protection,yet achieving simultaneous improvement in thermal stability and mechanical strength remains challenging.In this work,a vinyl-modified silicone resin(VMTQ)was synth...Phenolic resins are widely used in thermal protection,yet achieving simultaneous improvement in thermal stability and mechanical strength remains challenging.In this work,a vinyl-modified silicone resin(VMTQ)was synthesized and incorporated into a boron phenolic resin(BPF)matrix.Three composite ceramic fillers,Al_(2)O_(3)-SiO_(2)-ZrO_(2)(ASZ),Al_(2)O_(3)-SiO_(2)-TiO_(2)(AST),and Al_(2)O_(3)-SiO_(2)-MgO(ASM),were further introduced to construct a multi-oxide synergistic reinforcement system.Thermogravimetric analysis shows that the maximum decomposition rate decreases by 0.2-0.3%⋅min^(-1),while the ASM/V3/BPF-3 composite exhibits a 74.53%increase in char yield at 800℃and a 163.3℃increase in initial decomposition temperature,confirming its significantly enhanced thermal stability.SEM/EDS and XRDanalyses reveal thatASZ,AST,and ASM promote the formation of stable ceramic phases,withASM generating the densest MgO-Al_(2)O_(3)-SiO_(2)composite oxide layer.Mechanical testing demonstrates that ASZ improves vertical impact strength by 23.9%,AST increases parallel impact strength by 14.1%,andASMenhances bending strength by 34.5%(316.8 MPa).These results clearly indicate that the combination of VMTQ modification with multi-oxide ceramic fillers can effectively elevate both the thermal stability and mechanical performance of BPF-based composites,providing a practical pathway for designing high-performance resins for demanding thermal-environment applications.展开更多
Objective:Protein convertase subtilisin/Kexin type 9(PCSK9)has been found to be closely associated with the occurrence and development of numerous tumors.However,the precise role of PCSK9 and its relationship to the d...Objective:Protein convertase subtilisin/Kexin type 9(PCSK9)has been found to be closely associated with the occurrence and development of numerous tumors.However,the precise role of PCSK9 and its relationship to the development of hepatocellular carcinoma(HCC)remain largely unknown.This study aimed to clarify these issues.Methods:The expression levels of PCSK9 in HCC tissues and HCC cell lines were determined by the quantitative reverse transcription polymerase chain reaction,Western blot,and immunohistochemical analyses,and the effects of PCSK9 expression on HCC cell biological traits were investigated by overexpressing and downregulating PCSK9 expression in vivo and in vitro.Additionally,the mechanism by which PCSK9 mediated dissociation of glutathione S-transferase Pi 1(GSTP1)dimers and phosphorylation of the Jun N-terminal kinase(JNK)pathway components were investigated.Results:PCSK9 expression levels were significantly lower in HCC tissues than in adjacent non-tumor samples.In vivo and in vitro experiments suggested that PCSK9 inhibited HCC cell proliferation and metastasis.Further analysis showed that PCSK9 interacted with GSTP1 and promoted GSTP1 dimer dissociation and JNK signaling pathway inactivation in HCC cells.Moreover,the relationships between PCSK9 protein expressions and clinical outcomes were investigated.The PCSK9-lo group displayed a significantly shorter overall survival(OS;median OS:64.2 months vs.83.2 months;log-rank statistic:4.237;P=0.04)and recurrencefree survival(RFS;median RFS:26.5 months vs.46.6 months;log-rank statistic:10.498;P=0.001)time than the PCSK9-hi group.Conclusions:PCSK9 inhibited HCC cell proliferation,cell cycle progression,and apoptosis by interacting with GSTP1 and suppressing JNK signaling,suggesting that PCSK9 might act as a tumor suppressor and be a therapeutic target in HCC patients.展开更多
基金funded by Large-Scale Instrument and Equipment Sharing Service Platform of College of Chemistry,Chemical Engineering and Resource Utilization,NEFUsupported by the National Natural Science Foundation of China(Grant No.52273066)Undergraduate Training Programs for Innovations by Heilongjiang Province[grant number S202510225421].
文摘Phenolic resins are widely used in thermal protection,yet achieving simultaneous improvement in thermal stability and mechanical strength remains challenging.In this work,a vinyl-modified silicone resin(VMTQ)was synthesized and incorporated into a boron phenolic resin(BPF)matrix.Three composite ceramic fillers,Al_(2)O_(3)-SiO_(2)-ZrO_(2)(ASZ),Al_(2)O_(3)-SiO_(2)-TiO_(2)(AST),and Al_(2)O_(3)-SiO_(2)-MgO(ASM),were further introduced to construct a multi-oxide synergistic reinforcement system.Thermogravimetric analysis shows that the maximum decomposition rate decreases by 0.2-0.3%⋅min^(-1),while the ASM/V3/BPF-3 composite exhibits a 74.53%increase in char yield at 800℃and a 163.3℃increase in initial decomposition temperature,confirming its significantly enhanced thermal stability.SEM/EDS and XRDanalyses reveal thatASZ,AST,and ASM promote the formation of stable ceramic phases,withASM generating the densest MgO-Al_(2)O_(3)-SiO_(2)composite oxide layer.Mechanical testing demonstrates that ASZ improves vertical impact strength by 23.9%,AST increases parallel impact strength by 14.1%,andASMenhances bending strength by 34.5%(316.8 MPa).These results clearly indicate that the combination of VMTQ modification with multi-oxide ceramic fillers can effectively elevate both the thermal stability and mechanical performance of BPF-based composites,providing a practical pathway for designing high-performance resins for demanding thermal-environment applications.
基金supported by grants from the National Natural Science Foundation of China(Grant No.81802461)the Jiangxi Provincial Department of Science and Technology(Grant No.20202ACBL216012)the Education Department of Jiangxi Province(Grant No.GJJ170010)。
文摘Objective:Protein convertase subtilisin/Kexin type 9(PCSK9)has been found to be closely associated with the occurrence and development of numerous tumors.However,the precise role of PCSK9 and its relationship to the development of hepatocellular carcinoma(HCC)remain largely unknown.This study aimed to clarify these issues.Methods:The expression levels of PCSK9 in HCC tissues and HCC cell lines were determined by the quantitative reverse transcription polymerase chain reaction,Western blot,and immunohistochemical analyses,and the effects of PCSK9 expression on HCC cell biological traits were investigated by overexpressing and downregulating PCSK9 expression in vivo and in vitro.Additionally,the mechanism by which PCSK9 mediated dissociation of glutathione S-transferase Pi 1(GSTP1)dimers and phosphorylation of the Jun N-terminal kinase(JNK)pathway components were investigated.Results:PCSK9 expression levels were significantly lower in HCC tissues than in adjacent non-tumor samples.In vivo and in vitro experiments suggested that PCSK9 inhibited HCC cell proliferation and metastasis.Further analysis showed that PCSK9 interacted with GSTP1 and promoted GSTP1 dimer dissociation and JNK signaling pathway inactivation in HCC cells.Moreover,the relationships between PCSK9 protein expressions and clinical outcomes were investigated.The PCSK9-lo group displayed a significantly shorter overall survival(OS;median OS:64.2 months vs.83.2 months;log-rank statistic:4.237;P=0.04)and recurrencefree survival(RFS;median RFS:26.5 months vs.46.6 months;log-rank statistic:10.498;P=0.001)time than the PCSK9-hi group.Conclusions:PCSK9 inhibited HCC cell proliferation,cell cycle progression,and apoptosis by interacting with GSTP1 and suppressing JNK signaling,suggesting that PCSK9 might act as a tumor suppressor and be a therapeutic target in HCC patients.
