Graft copolymers of MMA （methyl methacrylate） with NRL （natural rubber latex） referred to as NR-g-PMMA have been prepared using CHP （cumene hydroperoxide）/TEPA （tetraetbylenepentamine） redox initiator. 1H NMR ...Graft copolymers of MMA （methyl methacrylate） with NRL （natural rubber latex） referred to as NR-g-PMMA have been prepared using CHP （cumene hydroperoxide）/TEPA （tetraetbylenepentamine） redox initiator. 1H NMR （proton nuclear magnetic resonance） and FTIR （Fourier transform infrared） analysis have confirmed the occurrence of graft copolymerisations of MMA onto NR that containing 30% and 50% of MMA monomer. The influence of coagulating agents such as formic acid, sulfuric acid and boiling water on the coagulation of NR-g-PMMA latices were investigated. These types of coagulating agent formed compact coagulum and the effect of NR-g-PMMA compounds on cure characteristics, physical properties and appearances were reported.展开更多
Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use...Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use of a carbon fiber microelectrode modified with a tetrasulfonated nickel phthalocyanine complex for the detection of MNP at a lower potential than that of direct phenol oxidation. The MNP voltammogram showed the presence of an anodic peak at -0.11 V vs SCE, corresponding to the oxidation of the hydroxylamine group generated after the reduction of the nitro group. The effect of buffer pH on the peak current and SWV parameters such as frequency, scan increment, and pulse amplitude were studied and optimized to have better electrochemical response of the proposed sensor. With these optimal parameters, the calibration curve shows that the peak current varied linearly as a function of MNP concentration, leading to a limit of detection (LoD) of 1.1 μg/L. These results show an appreciable sensitivity of the sensor for detecting the MNP at relatively low potentials, making it possible to avoid passivation phenomena.展开更多
目的研究在没有对照品的情况下鉴定检材中1-(4-氟苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluorophenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-α-PVP]类似物1-(4-氟-3甲基苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluoro-3-methyl phenyl)-2-(1-py...目的研究在没有对照品的情况下鉴定检材中1-(4-氟苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluorophenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-α-PVP]类似物1-(4-氟-3甲基苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluoro-3-methyl phenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-3-Methyl-α-PVP]盐酸盐的方法。方法综合利用直接进样电子电离-质谱(electron ionization-mass spectrometry,EI-MS)、GCMS、电喷雾离子化-高分辨质谱(electrospray ionization-high resolution mass spectrometry,ESI-HRMS)、超高效液相色谱-高分辨串联质谱(ultra-high performance liquid chromatography-high resolution tandem mass spectrometry,UPLC-HRMS/MS)、核磁共振(nuclear magnetic resonance,NMR)、离子色谱和傅里叶变换红外光谱法(Fourier transform infrared spectroscopy,FTIR),实现对检材中未知化合物的结构解析与表征,并对该化合物在EI-MS和UPLC-HRMS/MS两种质谱分析方式下生成碎片离子的裂解机制进行推导。结果通过对检材中化合物的直接进样EI-MS、GC-MS、ESI-HRMS和UPLC-HRMS/MS分析,推断出未知化合物为4-F-α-PVP的结构类似物,可能苯环中多了1个甲基。根据核磁共振氢谱(1H-nuclear magnetic reso⁃nance,1 H-NMR)、核磁共振碳谱(13C-nuclear magnetic resonance,13C-NMR)等分析结果,进一步证明了甲基的位置在苯环的3-位。由于1H-NMR分析中实际氢的个数比4-F-3-Methyl-α-PVP中性分子多1个,推断该化合物以盐形式存在。离子色谱法分析结果表明该化合物含氯离子(含量11.14%~11.16%),结合FTIR对主要官能团信息的结构分析,最终确定该未知化合物为4-F-3-Methyl-α-PVP盐酸盐。结论建立了综合利用EI-MS、GC-MS、ESI-HRMS、UPLC-HRMS/MS、NMR、离子色谱和FTIR鉴定检材中4-F-3-Methyl-α-PVP盐酸盐的方法,将有助于法庭科学实验室在案件中鉴定该物质或其他具有类似结构的化合物。展开更多
目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的s...目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的shRNA(shRNA-METTL5)转染TNBC细胞后,用CCK-8、集落形成、伤口愈合以及Transwell实验分别检测细胞增殖活性、迁移与侵袭,Western blot检测Wnt/β-catenin信号关键蛋白的表达。构建异种移植瘤模型,验证敲降METTL5对TNBC细胞在体内生长以及Wnt/β-catenin信号活性的影响。结果METTL5在TNBC肿瘤组织和细胞系中表达上调(P<0.01)。敲降METTL5可抑制TNBC细胞的增殖、迁移和侵袭并降低了Wnt/β-catenin信号分子β-catenin、细胞周期蛋白(Cyclin)D1、基质金属蛋白酶(MMP)-2和MMP-7的表达(均P<0.01)。体内实验显示,敲降METTL5减缓了移植瘤生长和Wnt/β-catenin信号活性。结论敲降METTL5能抑制TNBC细胞的增殖、迁移与侵袭,其作用可能与抑制Wnt/β-catenin信号通路有关。展开更多
Epigenetic changes of DNA, including methylation, have long been recognized as key indicators of various diseases, including aging, cancer, and neurological disorders. Biomarker discoveries based on distinct methylati...Epigenetic changes of DNA, including methylation, have long been recognized as key indicators of various diseases, including aging, cancer, and neurological disorders. Biomarker discoveries based on distinct methylation patterns for both hypermethylation and hypomethylation lead the way in discovery of novel diagnosis and treatment targets. Many different approaches are present to detect the level of methylation in whole genome (whole genome bisulfite sequencing, microarray) as well as at specific loci (methylation specific PCR). Cell-free DNA (cf-DNA) found in body fluids like blood provides information about DNA methylation and serves as a less invasive approach for genetic screening. Cell-free DNA and methylation screening technologies, when combined, have the potential to transform the way we approach genetic screening and personalized therapy. These technologies can help enhance disease diagnostic accuracy and inform the development of targeted therapeutics by providing a non-invasive way for acquiring genomic information and identifying disease-associated methylation patterns. We highlight the clinical benefits of using cell-free DNA (cf-DNA) liquid biopsy analysis and available methylation screening technologies that have been crucial in identifying biomarkers for disease from patients using a non-invasive way. Powering such biomarker discoveries are various methods of cf-DNA methylation analysis such as Bisulfite Sequencing and most recently, Methylation-Specific Restriction Enzyme (MSRE-seq) Analysis, paving the way for novel epigenetic biomarker discoveries for more robust diagnosis such as early disease detection, prognosis, monitoring of disease progression and treatment response as well as discovery of novel drug targets.展开更多
Adsorption on activated carbon is one of the most widely used methods for the removal of dyes. The objective of this study is to valorize the shells of Saba senegalensis from local product in Senegal in the form of ac...Adsorption on activated carbon is one of the most widely used methods for the removal of dyes. The objective of this study is to valorize the shells of Saba senegalensis from local product in Senegal in the form of activated carbon and to test its effectiveness for the removal of methyl violet. The study was carried out in batch mode for a maximum duration of one hour with 100 mL of solution treated at 600 rpm. The results reveal that the granulometry 500 μm gives the best yield with an adsorption rate of 95%, a mass of adsorbent of 0.2 g gives an adsorption capacity of 20 mg/g, the contact time of one hour with a capacity of 5 mg/g. The study also showed that the adsorption process of methyl violet is described by the pseudo-second order kinetic model with correlation coefficient of 0.99. Two adsorption isotherms were studied, and the results revealed that the Freundlich model better describes the adsorption of methyl violet on Saba senegalensis shell residue-based activated carbon (SSSRAC). The results indicate that SSSRAC could be used as a low-cost alternative for the removal of textile dyes such as methyl violet.展开更多
New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<s...New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).展开更多
With the help of model experiments, we are able to offer a detailed proposal for the inhibition of DNA duplication and no inhibition of RNA viral infectivity. As a backbone, we introduced methyl phosphotriester (MPTE)...With the help of model experiments, we are able to offer a detailed proposal for the inhibition of DNA duplication and no inhibition of RNA viral infectivity. As a backbone, we introduced methyl phosphotriester (MPTE). Duplex formation according to the traditional Watson and Crick base-pairing: [(MPTE)<sub>n−1</sub> DNA] * DNA and [(MPTE)<sub>n−1</sub> DNA] * RNA, where n = number of DNA and RNA bases. However, in the latter case, inhibition is obtained by reduction of the number of MPTE linkages, as is confirmed with model experiments and under biological conditions with micro (mi)RNA substrates. The latter results have recently been published. One or more single MPTEs are disseminated over different places of DNA without neighbour MPTEs (Prof. Wen-Yih Chen and his group, Taiwan).展开更多
目的:探索分化抑制因子(inhibitor of differentiation,ID)家族在慢性髓系白血病(chronic myeloid leukemia,CML)中的表达和启动子甲基化水平,并分析其临床意义。方法:应用定量PCR及定量甲基化特异性PCR的方法检测2010年1月至2017年12...目的:探索分化抑制因子(inhibitor of differentiation,ID)家族在慢性髓系白血病(chronic myeloid leukemia,CML)中的表达和启动子甲基化水平,并分析其临床意义。方法:应用定量PCR及定量甲基化特异性PCR的方法检测2010年1月至2017年12月期间江苏大学附属人民医院就诊的非恶性血液病患者(对照组)和CML患者骨髓单个核细胞中ID2/ID3/ID4表达及ID4启动子甲基化水平,通过分组分析ID家族异常的临床意义。结果:ID2及ID3表达在CML患者中均呈现显著上调(P<0.001,P<0.05),而ID4表达在CML患者中呈现显著下调(P<0.01)。其中,接受者操作特征曲线分析揭示ID2表达可作为CML鉴别的潜在分子标志物(AUC=0.895,P<0.001)。CML患者中ID4启动子高甲基化概率显著高于对照组患者(P=0.001),且ID4启动子甲基化与ID4表达呈现负相关(r=-0.424,P=0.002)。通过分组分析发现ID2高表达较易发生于男性患者中(P=0.040);ID4低表达/高甲基化较易发生于加速/急变期患者(P=0.003,P<0.001)。此外,CML加速/急变期患者ID4表达水平低于慢性期患者(P<0.001),而ID4甲基化水平高于慢性期患者(P<0.001)。通过单因素及多因素Logistic回归分析发现ID4高甲基化是CML患者疾病进展的独立危险因素(P=0.007)。结论:ID家族在CML患者中表达态势不同,其中ID2/ID3表达上调;而ID4表达下调,与ID4启动子高甲基化相关。ID4表达/甲基化与CML疾病进展相关,其中ID4甲基化可能是CML疾病进展的独立危险因素。展开更多
文摘Graft copolymers of MMA （methyl methacrylate） with NRL （natural rubber latex） referred to as NR-g-PMMA have been prepared using CHP （cumene hydroperoxide）/TEPA （tetraetbylenepentamine） redox initiator. 1H NMR （proton nuclear magnetic resonance） and FTIR （Fourier transform infrared） analysis have confirmed the occurrence of graft copolymerisations of MMA onto NR that containing 30% and 50% of MMA monomer. The influence of coagulating agents such as formic acid, sulfuric acid and boiling water on the coagulation of NR-g-PMMA latices were investigated. These types of coagulating agent formed compact coagulum and the effect of NR-g-PMMA compounds on cure characteristics, physical properties and appearances were reported.
文摘Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use of a carbon fiber microelectrode modified with a tetrasulfonated nickel phthalocyanine complex for the detection of MNP at a lower potential than that of direct phenol oxidation. The MNP voltammogram showed the presence of an anodic peak at -0.11 V vs SCE, corresponding to the oxidation of the hydroxylamine group generated after the reduction of the nitro group. The effect of buffer pH on the peak current and SWV parameters such as frequency, scan increment, and pulse amplitude were studied and optimized to have better electrochemical response of the proposed sensor. With these optimal parameters, the calibration curve shows that the peak current varied linearly as a function of MNP concentration, leading to a limit of detection (LoD) of 1.1 μg/L. These results show an appreciable sensitivity of the sensor for detecting the MNP at relatively low potentials, making it possible to avoid passivation phenomena.
文摘目的研究在没有对照品的情况下鉴定检材中1-(4-氟苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluorophenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-α-PVP]类似物1-(4-氟-3甲基苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluoro-3-methyl phenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-3-Methyl-α-PVP]盐酸盐的方法。方法综合利用直接进样电子电离-质谱(electron ionization-mass spectrometry,EI-MS)、GCMS、电喷雾离子化-高分辨质谱(electrospray ionization-high resolution mass spectrometry,ESI-HRMS)、超高效液相色谱-高分辨串联质谱(ultra-high performance liquid chromatography-high resolution tandem mass spectrometry,UPLC-HRMS/MS)、核磁共振(nuclear magnetic resonance,NMR)、离子色谱和傅里叶变换红外光谱法(Fourier transform infrared spectroscopy,FTIR),实现对检材中未知化合物的结构解析与表征,并对该化合物在EI-MS和UPLC-HRMS/MS两种质谱分析方式下生成碎片离子的裂解机制进行推导。结果通过对检材中化合物的直接进样EI-MS、GC-MS、ESI-HRMS和UPLC-HRMS/MS分析,推断出未知化合物为4-F-α-PVP的结构类似物,可能苯环中多了1个甲基。根据核磁共振氢谱(1H-nuclear magnetic reso⁃nance,1 H-NMR)、核磁共振碳谱(13C-nuclear magnetic resonance,13C-NMR)等分析结果,进一步证明了甲基的位置在苯环的3-位。由于1H-NMR分析中实际氢的个数比4-F-3-Methyl-α-PVP中性分子多1个,推断该化合物以盐形式存在。离子色谱法分析结果表明该化合物含氯离子(含量11.14%~11.16%),结合FTIR对主要官能团信息的结构分析,最终确定该未知化合物为4-F-3-Methyl-α-PVP盐酸盐。结论建立了综合利用EI-MS、GC-MS、ESI-HRMS、UPLC-HRMS/MS、NMR、离子色谱和FTIR鉴定检材中4-F-3-Methyl-α-PVP盐酸盐的方法,将有助于法庭科学实验室在案件中鉴定该物质或其他具有类似结构的化合物。
文摘Epigenetic changes of DNA, including methylation, have long been recognized as key indicators of various diseases, including aging, cancer, and neurological disorders. Biomarker discoveries based on distinct methylation patterns for both hypermethylation and hypomethylation lead the way in discovery of novel diagnosis and treatment targets. Many different approaches are present to detect the level of methylation in whole genome (whole genome bisulfite sequencing, microarray) as well as at specific loci (methylation specific PCR). Cell-free DNA (cf-DNA) found in body fluids like blood provides information about DNA methylation and serves as a less invasive approach for genetic screening. Cell-free DNA and methylation screening technologies, when combined, have the potential to transform the way we approach genetic screening and personalized therapy. These technologies can help enhance disease diagnostic accuracy and inform the development of targeted therapeutics by providing a non-invasive way for acquiring genomic information and identifying disease-associated methylation patterns. We highlight the clinical benefits of using cell-free DNA (cf-DNA) liquid biopsy analysis and available methylation screening technologies that have been crucial in identifying biomarkers for disease from patients using a non-invasive way. Powering such biomarker discoveries are various methods of cf-DNA methylation analysis such as Bisulfite Sequencing and most recently, Methylation-Specific Restriction Enzyme (MSRE-seq) Analysis, paving the way for novel epigenetic biomarker discoveries for more robust diagnosis such as early disease detection, prognosis, monitoring of disease progression and treatment response as well as discovery of novel drug targets.
文摘Adsorption on activated carbon is one of the most widely used methods for the removal of dyes. The objective of this study is to valorize the shells of Saba senegalensis from local product in Senegal in the form of activated carbon and to test its effectiveness for the removal of methyl violet. The study was carried out in batch mode for a maximum duration of one hour with 100 mL of solution treated at 600 rpm. The results reveal that the granulometry 500 μm gives the best yield with an adsorption rate of 95%, a mass of adsorbent of 0.2 g gives an adsorption capacity of 20 mg/g, the contact time of one hour with a capacity of 5 mg/g. The study also showed that the adsorption process of methyl violet is described by the pseudo-second order kinetic model with correlation coefficient of 0.99. Two adsorption isotherms were studied, and the results revealed that the Freundlich model better describes the adsorption of methyl violet on Saba senegalensis shell residue-based activated carbon (SSSRAC). The results indicate that SSSRAC could be used as a low-cost alternative for the removal of textile dyes such as methyl violet.
文摘New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).
文摘With the help of model experiments, we are able to offer a detailed proposal for the inhibition of DNA duplication and no inhibition of RNA viral infectivity. As a backbone, we introduced methyl phosphotriester (MPTE). Duplex formation according to the traditional Watson and Crick base-pairing: [(MPTE)<sub>n−1</sub> DNA] * DNA and [(MPTE)<sub>n−1</sub> DNA] * RNA, where n = number of DNA and RNA bases. However, in the latter case, inhibition is obtained by reduction of the number of MPTE linkages, as is confirmed with model experiments and under biological conditions with micro (mi)RNA substrates. The latter results have recently been published. One or more single MPTEs are disseminated over different places of DNA without neighbour MPTEs (Prof. Wen-Yih Chen and his group, Taiwan).
文摘目的:探索分化抑制因子(inhibitor of differentiation,ID)家族在慢性髓系白血病(chronic myeloid leukemia,CML)中的表达和启动子甲基化水平,并分析其临床意义。方法:应用定量PCR及定量甲基化特异性PCR的方法检测2010年1月至2017年12月期间江苏大学附属人民医院就诊的非恶性血液病患者(对照组)和CML患者骨髓单个核细胞中ID2/ID3/ID4表达及ID4启动子甲基化水平,通过分组分析ID家族异常的临床意义。结果:ID2及ID3表达在CML患者中均呈现显著上调(P<0.001,P<0.05),而ID4表达在CML患者中呈现显著下调(P<0.01)。其中,接受者操作特征曲线分析揭示ID2表达可作为CML鉴别的潜在分子标志物(AUC=0.895,P<0.001)。CML患者中ID4启动子高甲基化概率显著高于对照组患者(P=0.001),且ID4启动子甲基化与ID4表达呈现负相关(r=-0.424,P=0.002)。通过分组分析发现ID2高表达较易发生于男性患者中(P=0.040);ID4低表达/高甲基化较易发生于加速/急变期患者(P=0.003,P<0.001)。此外,CML加速/急变期患者ID4表达水平低于慢性期患者(P<0.001),而ID4甲基化水平高于慢性期患者(P<0.001)。通过单因素及多因素Logistic回归分析发现ID4高甲基化是CML患者疾病进展的独立危险因素(P=0.007)。结论:ID家族在CML患者中表达态势不同,其中ID2/ID3表达上调;而ID4表达下调,与ID4启动子高甲基化相关。ID4表达/甲基化与CML疾病进展相关,其中ID4甲基化可能是CML疾病进展的独立危险因素。
