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Erythropoietin-induced hepatocyte receptor A2 regulates effect of pyroptosis on gastrointestinal colorectal cancer occurrence and metastasis resistance
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作者 Yu-Kun Zhang Ran Shi +2 位作者 Ruo-Yu Meng Shui-Li Lin Mei Zheng 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第9期3781-3797,共17页
Erythropoietin-induced hepatocyte receptor A2(EphA2)is a receptor tyrosine kinase that plays a key role in the development and progression of a variety of tumors.This article reviews the expression of EphA2 in gastroi... Erythropoietin-induced hepatocyte receptor A2(EphA2)is a receptor tyrosine kinase that plays a key role in the development and progression of a variety of tumors.This article reviews the expression of EphA2 in gastrointestinal(GI)colorectal cancer(CRC)and its regulation of pyroptosis.Pyroptosis is a form of programmed cell death that plays an important role in tumor suppression.Studies have shown that EphA2 regulates pyrodeath through various signaling pathways,affecting the occurrence,development and metastasis of GI CRC.The overexpression of EphA2 is closely related to the aggressiveness and metastasis of GI CRC,and the inhibition of EphA2 can induce pyrodeath and improve the sensitivity of cancer cells to treatment.In addition,EphA2 regulates intercellular communication and the microenvironment through interactions with other cytokines and receptors,further influencing cancer progression.The role of EphA2 in GI CRC and its underlying mechanisms provide us with new perspectives and potential therapeutic targets,which have important implications for future cancer treatment. 展开更多
关键词 Colorectal cancer PYROPTOSIS Erythropoietin-induced hepatocyte receptor A2 Tumor metastasis Drug resistance
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2-O-α-D-葡萄糖基-L-抗坏血酸的酶法合成及其应用研究进展
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作者 项蓉 王丹芸 +6 位作者 娄婷婷 吴子健 张宏宇 王素英 赵彦巧 张得光 马兴 《食品研究与开发》 CAS 2024年第1期201-210,共10页
2-O-α-D-葡萄糖基-L-抗坏血酸(2-O-D-glucopyranosyl-L-ascorbic acid,AA-2G)不仅稳定性强且保留了L-抗坏血酸(L-ascorbic acid,L-AA)的大部分生理活性,是L-AA最好的替代品。体外酶法合成AA-2G具有经济、快速、绿色和安全等显著优势,... 2-O-α-D-葡萄糖基-L-抗坏血酸(2-O-D-glucopyranosyl-L-ascorbic acid,AA-2G)不仅稳定性强且保留了L-抗坏血酸(L-ascorbic acid,L-AA)的大部分生理活性,是L-AA最好的替代品。体外酶法合成AA-2G具有经济、快速、绿色和安全等显著优势,是规模化生产AA-2G的可行方法。该文综述体外酶法合成AA-2G的研究进展,重点梳理环糊精糖基转移酶和蔗糖磷酸化酶合成AA-2G的研究现状,并对AA-2G的功能及应用前景进行讨论和展望。 展开更多
关键词 l-抗坏血酸 2-O-α-D-葡萄糖基-l-抗坏血酸 酶法合成 糖基转移酶 功能
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Metabolism of N-phenyl-2-naphthylamine andN-phenyl-1-naphthylamine by rat hepaticmicrosomes and hepatocytes
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作者 Thomas Wolff 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1992年第1期74-83,共10页
The carcinogenic antioxidants,N-phenyl-1-naphthylamine (P1NA)and N-phenyl-2-naphthylamine (P2NA) were examined in vitro for biotransformation by rat hepatic microsomes and in freshly isolated hepatocytes. HPLC-analysi... The carcinogenic antioxidants,N-phenyl-1-naphthylamine (P1NA)and N-phenyl-2-naphthylamine (P2NA) were examined in vitro for biotransformation by rat hepatic microsomes and in freshly isolated hepatocytes. HPLC-analysis of hepatocyte incubations with revealed that phenols were the major metabolites in both cases. P1NA formed one phenolic metabolite only, while incubation with P2NA yielded two phenols identified as 6-hydroxy-P2NA and 4'-hydroxy-P2NA by cochromatography with authentic samples. β-naphthylamine, a metabolite indicating dephenylation of P2NA was not detectable.Metabolism studies with microsomes revealed that the phenols were formed by cytochrome P-450 dependent monooxygenases. Pretreatment of animals with phenobarbital and 3-methylcholanthrene both increased the rate of microsomal metabolism of P1NA and P2NA, indicating that more than one P-450 enzyme mediate the oxygenation reaction. Animal pretreatment with single and repeated doses of P1NA and P2NA did not markedly stimulate metabolism, but induced ethylmorphine demethylatior. in males and females and benzo (a)pyrene hydroxylation in females. 展开更多
关键词 N-phenyl-2-naphthylamine N-phenyl-1-naphthylamine hepatocytes.
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过量表达甲酸脱氢酶提高大肠杆菌合成L-2-氨基丁酸的效率
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作者 李莹 史红玲 +3 位作者 王喆 冉璐妮 薛闯 唐存多 《精细化工》 EI CAS CSCD 北大核心 2023年第5期1048-1054,1072,共8页
为了实现L-2-氨基丁酸(L-ABA)的高效生物合成,借助pACYCDuet-1和pET28a共表达系统,构建了携带L-苏氨酸脱氨酶(L-TD)、L-亮氨酸脱氢酶(L-L-DH)和不同活性甲酸脱氢酶(FDH)编码基因的重组大肠杆菌,分别命名为:E.coli BL21(DE3)/pACYCDuet-1... 为了实现L-2-氨基丁酸(L-ABA)的高效生物合成,借助pACYCDuet-1和pET28a共表达系统,构建了携带L-苏氨酸脱氨酶(L-TD)、L-亮氨酸脱氢酶(L-L-DH)和不同活性甲酸脱氢酶(FDH)编码基因的重组大肠杆菌,分别命名为:E.coli BL21(DE3)/pACYCDuet-1-Ec TD-Es LeuDH:pET28a-Cb FDH和E.coli BL21(DE3)/p ACYCDuet-1-Ec TD-Es Leu DH:p ET28a-Cb FDH^(M)。经诱导表达后,L-苏氨酸脱氨酶和L-亮氨酸脱氢酶在两个重组大肠杆菌中的表达水平基本一致,而后者的甲酸脱氢酶酶活表达水平为(342.00±9.40)IU/mL,显著高于前者的(196.00±6.20)IU/mL。在50 mL反应体系中,200 mmol/L L-苏氨酸经220 r/min、30℃下反应6 h时,前者L-ABA得率为71%,后者为85%。结果表明,提高甲酸脱氢酶的表达水平可以显著提高L-ABA的合成效率。此外,优化反应温度后,在35℃下反应6 h时,L-ABA的得率可达90%。 展开更多
关键词 l-2-氨基丁酸 l-苏氨酸 共表达 微生物细胞工厂 全细胞催化 生物工程
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L-脯氨酸拆分1,1′-联-2-萘酚的实验设计
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作者 胡晓允 李康 +1 位作者 周忠强 张道洪 《实验室科学》 2023年第4期10-13,共4页
为了将手性化合物的包结拆分法引入有机化学实验教学,设计了有机化学综合实验“L-脯氨酸拆分1,1′-联-2-萘酚”:将L-脯氨酸和外消旋联萘酚研磨后,乙腈回流后析出L-脯氨酸和(S)-BINOL形成的包合物,(R)-BINOL留在溶液中。该综合实验实现... 为了将手性化合物的包结拆分法引入有机化学实验教学,设计了有机化学综合实验“L-脯氨酸拆分1,1′-联-2-萘酚”:将L-脯氨酸和外消旋联萘酚研磨后,乙腈回流后析出L-脯氨酸和(S)-BINOL形成的包合物,(R)-BINOL留在溶液中。该综合实验实现了光学纯联萘酚的高效拆分,创新了教学体系。实践表明,该综合实验采用基于非共价键作用的包结拆分法进行手性拆分,激发了学生的学习兴趣;此外,该实验综合性强,有利于学生动手操作能力、分析和解决综合问题能力的培养。 展开更多
关键词 包结拆分 l-脯氨酸 1 1′-联-2-萘酚
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解木糖赖氨酸芽孢杆菌发酵和生物催化产生L-2-氨基己二酸
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作者 刘姣 夏仕文 黄文薪 《分子催化》 CAS CSCD 北大核心 2023年第3期285-292,I0003,共9页
以解木糖赖氨酸芽孢杆菌XX-2为出发菌株,110 mmol/L L-赖氨酸单盐酸盐为发酵前体,144 h发酵后L-2-氨基己二酸浓度达到10.4 mmol/L,产率为9.5%.以解木糖赖氨酸芽孢杆菌XX-2全细胞为生物催化剂,利用共生的L-赖氨酸6-脱氢酶和?-1-哌啶啉-6... 以解木糖赖氨酸芽孢杆菌XX-2为出发菌株,110 mmol/L L-赖氨酸单盐酸盐为发酵前体,144 h发酵后L-2-氨基己二酸浓度达到10.4 mmol/L,产率为9.5%.以解木糖赖氨酸芽孢杆菌XX-2全细胞为生物催化剂,利用共生的L-赖氨酸6-脱氢酶和?-1-哌啶啉-6-羧酸脱氢酶催化L-赖氨酸单盐酸盐转化为L-2-氨基己二酸.最优条件为:细胞浓度为45 g(干重)/L,L-赖氨酸单盐酸盐浓度为100 mmol/L,pH=7.0,温度为30℃,反应时间144 h.在最优条件下,从100 mmol/L L-赖氨酸单盐酸盐产生90 mmol/L L-2-氨基己二酸,产率为90%.我们推测了生物催化过程中L-2-氨基己二酸产生的反应机理. 展开更多
关键词 解木糖赖氨酸芽孢杆菌XX-2 发酵 生物催化 l-2-氨基己二酸 l-赖氨酸6-脱氢酶 ?-1-哌啶啉-6-羧酸脱氢酶
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Gasdermin D-mediated hepatocyte pyroptosis expands inflammatory responses that aggravate acute liver failure by upregulating monocyte chemotactic protein 1/CC chemokine receptor-2 to recruit macrophages 被引量:10
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作者 Hong Li Xue-Ke Zhao +9 位作者 Yi-Ju Cheng Quan Zhang Jun Wu Shuang Lu Wei Zhang Yang Liu Ming-Yu Zhou Ya Wang Jing Yang Ming-Liang Cheng 《World Journal of Gastroenterology》 SCIE CAS 2019年第44期6527-6540,共14页
BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its me... BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its mechanisms of expanding inflammatory responses in ALF are unclear.AIM To investigate the role and mechanisms of GSDMD-mediated hepatocyte pyroptosis through in vitro and in vivo experiments.METHODS The expression of pyroptosis pathway-associated proteins in liver tissues from ALF patients and a hepatocyte injury model was examined by Western blot.GSDMD short hairpin RNA(shRNA)was used to investigate the effects of downregulation of GSDMD on monocyte chemotactic protein 1(MCP1)and its receptor CC chemokine receptor-2(CCR2)in vitro.For in vivo experiments,we used GSDMD knockout mice to investigate the role and mechanism of GSDMD in a D-galactose/lipopolysaccharide(D-Galn/LPS)-induced ALF mouse model.RESULTS The levels of pyroptosis pathway-associated proteins in liver tissue from ALF patients and a hepatocyte injury model increased significantly.The level of GSDMD-N protein increased most obviously(P<0.001).In vitro,downregulation of GSDMD by shRNA decreased the cell inhibition rate and the levels of MCP1/CCR2 proteins(P<0.01).In vivo,GSDMD knockout dramatically eliminated inflammatory damage in the liver and improved the survival of DGaln/LPS-induced ALF mice(P<0.001).Unlike the mechanism of immune cell pyroptosis that involves releasing interleukin(IL)-1βand IL-18,GSDMDmediated hepatocyte pyroptosis recruited macrophages via MCP1/CCR2 to aggravate hepatocyte death.However,this pathological process was inhibited after knocking down GSDMD.CONCLUSION GSDMD-mediated hepatocyte pyroptosis plays an important role in the pathogenesis of ALF,recruiting macrophages to release inflammatory mediators by upregulating MCP1/CCR2 and leading to expansion of the inflammatory responses.GSDMD knockout can reduce hepatocyte death and inflammatory responses,thus alleviating ALF. 展开更多
关键词 Gasdermin D hepatocyte PYROPTOSIS Acute liver failure MONOCYTE chemotactic PROTEIN 1/CC chemokine receptor-2
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Effects of hepatocyte growth factor on MMP-2 expression in scleral fibroblasts from a guinea pig myopia model 被引量:6
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作者 Xiu-Juan Li Xiao-Peng Yang +2 位作者 Guang-Ming Wan Yu-Ying Wang Jin-Song Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第2期239-244,共6页
AIMTo investigate the effects of hepatocyte growth factor (HGF) on MMP-2 expression in scleral fibroblasts from guinea pig with LIM.
关键词 MYOPIA FIBROBLASTS hepatocyte growth factor MMP-2 guinea pig
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CYP2E1-dependent hepatotoxicity and oxidative damage after ethanol administration in human primary hepatocytes 被引量:12
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作者 Lie-Gang Liu Hong Yan Ping Yao Wen Zhang Li-Jun Zou Fang-Fang Song Ke Li Xiu-Fa Sun 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第29期4530-4535,共6页
AIM: To observe the relationship between ethanol-induced oxidative damage in human primary cultured hepatocytes and cytochrome P450 2E1 (CYP2E1) activity, in order to address if inhibition of CYP2E1 could attenuate... AIM: To observe the relationship between ethanol-induced oxidative damage in human primary cultured hepatocytes and cytochrome P450 2E1 (CYP2E1) activity, in order to address if inhibition of CYP2E1 could attenuate ethanol- induced cellular damage. METHODS: The dose-dependent (25-100 mmol/L) and time-dependent (0-24 h) exposures of primary human cultured hepatocytes to ethanol were carried out. CYP2E1 activity and protein expression were detected by spectrophotometer and Western blot analysis respectively. Hepatotoxicity was investigated by determination of lactate dehydrogenase (LDH) and aspartate transaminase (AST) level in hepatocyte culture supernatants, as well as the intracellular formation of malondialdehyde (MDA). RESULTS: A dose-and time-dependent response between ethanol exposure and CYP2E1 activity in human hepatocytes was demonstrated. Moreover, there was a time-dependent increase of CYP2E1 protein after 100 mmol/L ethanol exposure. Meanwhile, ethanol exposure of hepatocytes caused a time-dependent increase of cellular MDA level, LDH, and AST activities in supernatants. Furthermore, the inhibitor of CYP2E1, diallyl sulfide (DAS) could partly attenuate the increases of MDA, LDH, and AST in human hepatocytes. CONCLUSION: A positive relationship between ethanolinduced oxidative damage in human primary cultured hepatocytes and CYP2E1 activity was exhibited, and the inhibition of CYP2E1 could partly attenuate ethanol-induced oxidative damage. 展开更多
关键词 ETHANOL CYP2E1 Oxidative damage Human primary hepatocytes
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Calpain-2 activity promotes aberrant endoplasmic reticulum stress-related apoptosis in hepatocytes 被引量:5
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作者 Ru-Jia Xie Xiao-Xia Hu +6 位作者 Lu Zheng Shuang Cai Yu-Si Chen Yi Yang Ting Yang Bing Han Qin Yang 《World Journal of Gastroenterology》 SCIE CAS 2020年第13期1450-1462,共13页
BACKGROUND Calpain-2 is a Ca^2+-dependent cysteine protease,and high calpain-2 activity can enhance apoptosis mediated by multiple triggers.AIM To investigate whether calpain-2 can modulate aberrant endoplasmic reticu... BACKGROUND Calpain-2 is a Ca^2+-dependent cysteine protease,and high calpain-2 activity can enhance apoptosis mediated by multiple triggers.AIM To investigate whether calpain-2 can modulate aberrant endoplasmic reticulum(ER)stress-related apoptosis in rat hepatocyte BRL-3A cells.METHODS BRL-3A cells were treated with varying doses of dithiothreitol(DTT),and their viability and apoptosis were quantified by 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2-H-tetrazolium bromide and flow cytometry.The expression of ER stress-and apoptosis-related proteins was detected by Western blot analysis.The protease activity of calpain-2 was determined using a fluorescent substrate,Nsuccinyl-Leu-Leu-Val-Tyr-AMC.Intracellular Ca^2+content,and ER and calpain-2 co-localization were characterized by fluorescent microscopy.The impact of calpain-2 silencing by specific small interfering RNA on caspase-12 activation and apoptosis of BRL-3A cells was quantified.RESULTS DTT exhibited dose-dependent cytotoxicity against BRL-3A cells and treatment with 2 mmol/L DTT triggered BRL-3A cell apoptosis.DTT treatment significantly upregulated 78 kDa glucose-regulated protein,activating transcription factor 4,C/EBP-homologous protein expression by>2-fold,and enhanced PRKR-like ER kinase phosphorylation,caspase-12 and caspase-3 cleavage in BRL-3A cells in a trend of time-dependence.DTT treatment also significantly increased intracellular Ca^2+content,calpain-2 expression,and activity by>2-fold in BRL-3A cells.Furthermore,immunofluorescence revealed that DTT treatment promoted the ER accumulation of calpain-2.Moreover,calpain-2 silencing to decrease calpain-2 expression by 85%significantly mitigated DTT-enhanced calpain-2 expression,caspase-12 cleavage,and apoptosis in BRL-3A cells.CONCLUSION The data indicated that Ca^2+-dependent calpain-2 activity promoted the aberrant ER stress-related apoptosis of rat hepatocytes by activating caspase-12 in the ER. 展开更多
关键词 Calcium Calpain-2 CASPASE-12 Endoplasmic reticulum stress APOPTOSIS hepatocyte
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IRS-2通过PI3K/AKT通路调控肝细胞焦亡的实验研究
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作者 郭庆鑫 姚婷 +4 位作者 沈乐而 陈金梅 胡微微 张毅 陈小华 《肝脏》 2024年第5期561-566,共6页
目的探讨胰岛素受体底物(IRS-2)在过氧化氢(H2O2)诱导肝细胞焦亡中的作用及分子机制。方法H2O2刺激HepG2与L02细胞系。构建IRS-2 siRNA,在HepG2与L02细胞系中抑制IRS-2基因表达,Western印迹法检测细胞IRS-2与焦亡相关蛋白表达水平。CCK-... 目的探讨胰岛素受体底物(IRS-2)在过氧化氢(H2O2)诱导肝细胞焦亡中的作用及分子机制。方法H2O2刺激HepG2与L02细胞系。构建IRS-2 siRNA,在HepG2与L02细胞系中抑制IRS-2基因表达,Western印迹法检测细胞IRS-2与焦亡相关蛋白表达水平。CCK-8法检测细胞活性,流式细胞仪检测线粒体膜电位变化,电镜下观测细胞形态、线粒体与焦亡小体,Mito-Track Green观测线粒体形态与数量。IRS-2 siRNA单独或联合PI3K/AKT通路激动剂刺激HepG2与L02细胞系,检测PI3K/AKT通路蛋白与焦亡相关蛋白表达水平。结果与对照组相比,H2O2可降低肝细胞活率,降低IRS-2蛋白表达,提高细胞焦亡相关蛋白表达。下调细胞内IRS-2表达可导致肝细胞线粒体功能障碍,肝细胞形态发生破坏,焦亡小体数量增多,上调细胞焦亡相关蛋白表达水平,P-PI3K/PI3K与P-AKT/AKT比值下调。激活PI3K/AKT通路可逆转IRS-2下调导致的肝细胞焦亡相关蛋白表达。结论H2O2刺激肝细胞能降低IRS-2蛋白表达,诱导细胞焦亡。抑制IRS-2表达可能通过减少PI3K/AKT通路激活导致线粒体功能障碍,诱导肝细胞焦亡。 展开更多
关键词 IRS-2 PI3K/AKT通路 焦亡 肝细胞 线粒体功能障碍
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Association of A Common Haplotype of Hepatocyte Nuclear Factor 1α With Type 2 Diabetes in Chinese Population 被引量:2
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作者 CONG-RONG WANG CHENG HU RONG ZHANG QI-CHEN FANG XIAO-JING MA WEI-PING JIA KUN-SAN XIANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第1期41-46,共6页
Objective To analyze the association of variants of hepatocyte nuclear factor-1α (HNF-1α) gene with type 2 diabetes in Chinese population. Methods In 152 unrelated type 2 diabetes patients and 93 unrelated control... Objective To analyze the association of variants of hepatocyte nuclear factor-1α (HNF-1α) gene with type 2 diabetes in Chinese population. Methods In 152 unrelated type 2 diabetes patients and 93 unrelated controls, eleven single nucleotide polymorphisms (SNPs) were identified and genotyped. Statistical analyses were performed to investigate whether these SNPs were associated with diabetes status in our samples. Results In the individual SNP study, no SNP differed significantly in frequency between type 2 diabetes patients and controls. In the haplotype analysis, two haplotype blocks were identified. In haplotype block 1, no evidence was found between common HNF-1α haplotypes and type 2 diabetes. However, in haplotype block 2, a common haplotype GCGC formed by four tagging SNPs (tSNPs) was found to be associated with decreased risk of type 2 diabetes (odds ratio [OR] 0.6011, 95% confidence interval [CI] 0.4138-0.8732, P=0.0073, empirical P=0.0511, permutation test). A similar trend was also observed in the diplotype analysis, indicating that the increasing copy number of the haplotype GCGC was associated with the decreased frequency of diabetes (P=0.0193). Conclusion The results of this study provide evidence that the haplotype of HNF-1α decreases the risk of type 2 diabetes in Chinese individuals. 展开更多
关键词 hepatocyte nuclear factor-1α Type2 diabetes SNP Haplotype analysis
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2维薛定谔方程的一种高精度紧致差分格式
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作者 依力米努尔·尼扎木 开依沙尔·热合曼 《江西师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期189-193,共5页
该文对2维薛定谔方程利用局部一维化方法,将2维方程分裂为x、y方向的2个1维薛定谔方程,然后采用6阶紧致格式的离散方法来处理空间变量的2阶导数项,将薛定谔方程转化为一个常微分方程组.通过L-稳定Simpson方法对上述空间离散化得到的常... 该文对2维薛定谔方程利用局部一维化方法,将2维方程分裂为x、y方向的2个1维薛定谔方程,然后采用6阶紧致格式的离散方法来处理空间变量的2阶导数项,将薛定谔方程转化为一个常微分方程组.通过L-稳定Simpson方法对上述空间离散化得到的常微分方程进行离散化,得到了一种具有空间6阶精度和时间3阶精度的格式,并证明了该格式无条件稳定性.并通过数值模拟和对比方法验证了格式的有效性. 展开更多
关键词 2维薛定谔方程 高精度紧致差分格式 局部1维化方法 l-稳定Simpson方法
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2维带色散4阶扩散方程的高精度紧致格式
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作者 王红玉 李冉冉 开依沙尔·热合曼 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第4期27-35,共9页
针对1,2维带色散4阶扩散方程提出了一种高精度紧致格式.首先采用局部1维化方法将2维问题转化为x,y方向的两个1维带色散4阶扩散方程,其次分别对3,4阶空间导数进行6阶紧致格式离散,把带色散4阶扩散方程转化为一个常微分方程组,再利用求解... 针对1,2维带色散4阶扩散方程提出了一种高精度紧致格式.首先采用局部1维化方法将2维问题转化为x,y方向的两个1维带色散4阶扩散方程,其次分别对3,4阶空间导数进行6阶紧致格式离散,把带色散4阶扩散方程转化为一个常微分方程组,再利用求解常微分方程组的L-稳定的Simpson方法构造时间3阶、空间6阶精度的数值格式,并证明该格式是绝对稳定的.通过数值实验和比较,验证论文格式的有效性. 展开更多
关键词 2维带色散4阶扩散方程 高精度紧致差分格式 CRANK-NICOLSON格式 局部1维化方法 l-稳定Simpson格式
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转录因子HNF1A、HNF4A和FOXA2调节肝细胞蛋白质N-糖基化
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作者 Vedrana Vicic Bockor Nika Foglar +7 位作者 Goran Josipovic Marija Klasic Ana Vujic Branimir Plavsa Toma Keser Samira Smajlovic Aleksandar Vojta Vlatka Zoldos 《Engineering》 SCIE EI CAS CSCD 2024年第1期57-68,共12页
Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulator... Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulatory transcriptional loop.The Encode and ChIP-Atlas databases identify the recognition sites of these transcription factors in many glycosyltransferase genes.Our in silico analysis of HNF1A,HNF4A.and FOXA2 binding to the ten candidate glyco-genes studied in this work confirms a significant enrich-ment of these transcription factors specifically in the liver.Our previous studies identified HNF1A as a master regulator of fucosylation,glycan branching,and galactosylation of plasma glycoproteins.Here,we aimed to functionally validate the role of the three transcription factors on downstream glyco-gene transcriptional expression and the possible effect on glycan phenotype.We used the state-of-the-art clus-tered regularly interspaced short palindromic repeats/dead Cas9(CRISPR/dCas9)molecular tool for the downregulation of the HNF1A,HNF4A,and FOXA2 genes in HepG2 cells-a human liver cancer cell line.The results show that the downregulation of all three genes individually and in pairs affects the transcrip-tional activity of many glyco-genes,although downregulation of glyco-genes was not always followed by an unambiguous change in the corresponding glycan structures.The effect is better seen as an overall change in the total HepG2 N-glycome,primarily due to the extension of biantennary glycans.We propose an alternative way to evaluate the N-glycome composition via estimating the overall complexity of the glycome by quantifying the number of monomers in each glycan structure.We also propose a model showing feedback loops with the mutual activation of HNF1A-FOXA2 and HNF4A-FOXA2 affecting glyco-genes and protein glycosylation in HepG2 cells. 展开更多
关键词 Clustered regularly interspaced short palindromic repeats/dead Cas9(CRISPR/dCas9) EPIGENETICS hepatocyte nuclear factor 1 alpha(HNF1A) hepatocyte nuclear factor 4 alpha(HNF4A) Forkhead box protein A2(FOXA2) N-GLYCOSYLATION HepG2 cells
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Association of hepatocyte-derived growth factor receptor/caudal type homeobox 2 co-expression with mucosal regeneration in active ulcerative colitis 被引量:2
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作者 Ferenc Sipos Miklós Constantinovits +2 位作者 Gábor Valcz Zsolt Tulassay Gy?rgyi M?zes 《World Journal of Gastroenterology》 SCIE CAS 2015年第28期8569-8579,共11页
AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood... AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood samples and 38 colonic biopsy samples from 18 patients with histologically proven active UC and 20 healthy control subjects were collected.After preparing tissue microarrays and blood smears HGFR,caudal type homeobox 2(CDX2),prominin-1(CD133) and Musashi-1conventional and double fluorescent immunolabelings were performed.Immunostained samples were digitalized using high-resolution Mirax Desk instrument,and analyzed with the Mirax TMA Module software.For semiquantitative counting of immunopositive lamina propria(LP) cells 5 fields of view were counted at magnification x 200 in each sample core,then mean ± SD were determined.In case of peripheral blood smears,30 fields of view with 100 μm diameter were evaluated in every sample and the number of immunopositive cells(mean ± SD) was determined.Using 337 nm UVA Laser MicroDissection system at least 5000 subepithelial cells from the lamina propria were collected.Gene expression analysis of HGFR,CDX2,CD133,leucine-rich repeat-containing G-protein coupled receptor 5(Lgr5),Musashi-1 and cytokeratin20(CK20) were performed in both laser-microdisscted samples and blood samples by using real time reverse transcription polymerase chain reaction(RT-PCR).RESULTS:By performing conventional and double fluorescent immunolabelings confirmed by RT-PCR,higher number of HGFR(blood:6.7 ± 1.22 vs 38.5 ±3.18;LP:2.25 ± 0.85 vs 9.22 ± 0.65;P < 0.05),CDX2(blood:0 vs 0.94 ± 0.64;LP:0.75 ± 0.55 vs 2.11± 0.75;P < 0.05),CD133(blood:1.1 ± 0.72 vs 8.3± 1.08;LP:11.1 ± 0.85 vs 26.28 ± 1.71;P < 0.05)and Musashi-1(blood and LP:0 vs scattered) positive cells were detected in blood and lamina propria of UC samples as compared to controls.HGFR/CDX2(blood:0 vs 1± 0.59;LP:0.8 ± 0.69 vs 2.06 ± 0.72,P < 0.05)and Musashi-1/CDX2(blood and LP:0 vs scattered) coexpressions were found in blood and lamina propria of UC samples.HGFR/CD133 and CD133/CDX2 coexpressions appeared only in UC lamina propria samples.CDX2,Lgr5 and Musashi-1 expressions in UC blood samples were not accompanied by CK20 mRNA expression.CONCLUSION:In active UC,a portion of circulating HGFR-expressing cells are committed to the epithelial lineage,and may participate in mucosal regeneration by undergoing mesenchymal-to-epithelial transition. 展开更多
关键词 hepatocyte-derived growth factor RECEPTOR CAUDAL type HOMEOBOX 2 CD133 Musashi-1 Leucinerichrepeat-containing G-protein coupled RECEPTOR 5 Ulcerative colitis REGENERATION
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Long-term culture of primary porcine mature hepatocytes in the medium supplemented with ascorbic acid 2-phosphate
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作者 Yohichi Kumaki Iku Kumaki +7 位作者 Xiaomei Guo Weilin Shang Toshie Koyama Ai Okamura Yoshiaki Shiba Toshiyuki Mukaiyama Noriko Sasaki Makoto Kodama 《Natural Science》 2010年第11期1264-1273,共10页
In this study, the effect of ascorbic acid 2-phosphate (Asc2P) was tested on porcine and rat mature hepatocytes in vitro. a). Asc2P increased the porcine, but not rat, albumin secretion and mRNA expression. The enhanc... In this study, the effect of ascorbic acid 2-phosphate (Asc2P) was tested on porcine and rat mature hepatocytes in vitro. a). Asc2P increased the porcine, but not rat, albumin secretion and mRNA expression. The enhancing effect of Asc2P on porcine C/EBP alpha mRNA was observed in porcine mature hepatocytes. These data suggested that Asc2P played an important role in the regulation of porcine albumin mRNA level. b). The enhancing effect of Asc2P on ammonium metabolic activity was also observed in porcine, but not rat, mature hepatocytes. The porcine ornithine transcarbamylase (OTC) and arginase mRNAs were augmented by Asc2P, indicating that Asc2P had a direct effect on the urea cycle. c). The porcine collagen type I and type III mRNA, but not type XII mRNA, were detected as well, sugessting that Asc2P did not have the effect on the non-parenchymal hepatocytes to induce collagen type I and III mRNA expression. d). Our RT-PCR analysis demonstrated that the porcine hepatocytes expressed the sodium-ascorbate co-transporters SVCT1 and SVCT2, however, the intensities of porcine sodium-ascorbate co-transporters SVCT1 and SVCT2 bands were not changed markedly. These findings indicated that the Asc2P had no effect on SVCT1 and SVCT2 mRNA expression. e). The enhancing effect of Asc2P on porcine albumin mRNA was inhibited by staurosporine, a portein kinase inhibitor. We conclude that the enhanced albumin mRNA by Asc2P might be due to activation of tyrosine protein kinase and/or PKC and the Asc2P enhanced porcine albumin mRNA mainly at the transcriptional step. 展开更多
关键词 ALBUMIN Secretion Ammonium Metabolic Activity Ascorbic Acid 2-Phosphate PORCINE hepatocyteS Reverse Transcriptase-Polymerase Chain Reaction
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ENHANCEMENT OF DNA SYNTHESIS IN CULTURED ADULT RAT HEPATOCYTES BY 5-HT THROUGH STIMULATION OF 5-HT_2RECEPTOR
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作者 符兆英 《Journal of Pharmaceutical Analysis》 CAS 1999年第1期15-19,共5页
Hepatocytes were isolated from livers of adult male SpragueDawley rats and cultured in Williams'E Medium with 3 H thymidine. The effect of 5hydroxytryptamine (5HT) was investigated through adding various concentra... Hepatocytes were isolated from livers of adult male SpragueDawley rats and cultured in Williams'E Medium with 3 H thymidine. The effect of 5hydroxytryptamine (5HT) was investigated through adding various concentrations (10-810-3 mol/L) of 5HT to the hepatocyte cultures in the presence or absence of epidermal growth factor (EGF) and insulin. The involvement of 5HT2 receptor was examined by adding a 5HT2 receptor antagonist, ketanserin (10-6 mol/L), to some of the cultures containing 5HT. The increment of DNA synthesis was measured by 3 H thymidine incorporation. The results showed that 5HT2 (10-6 mol/L) significantly (P<005) increased the amount of DNA synthesis induced by EGF and insulin in the cultured adult rat hepaptocytes. The effect of 5HT in enhancing DNA synthesis began to appear at a concentration between 10-7 and 10-6 mol/L and reached maximum at concentrations of 10-4 mol/L. The enhancement of DNA synthesis by 5HT was significantly (P<005) antagonized by ketanserin, suggesting that this effect of 5HT was mediated by 5HT2 receptor subtype. 展开更多
关键词 DNA synthesis hepatocyte 5hydroxytryptamine (5HT) 5HT2 receptor
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Induction of Cytochrome P450 2A6 by Bilirubin in Human Hepatocytes
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作者 Hiromi Tanii Yoshihisa Shitara +3 位作者 Mikako Torii Shuichi Sekine Hiroshi Iwata Toshiharu Horie 《Pharmacology & Pharmacy》 2013年第2期182-190,共9页
The influence of bilirubin on mRNA expression of cytochrome P450 (CYP), UDP-glucuronosyltransferase (UGT) and nuclear receptors in human hepatocytes was investigated. The treatment of the hepatocytes with 40 μg/mL bi... The influence of bilirubin on mRNA expression of cytochrome P450 (CYP), UDP-glucuronosyltransferase (UGT) and nuclear receptors in human hepatocytes was investigated. The treatment of the hepatocytes with 40 μg/mL bilirubin, which corresponds to hyperbilirubinemia, resulted in 1.7-fold increase of CYP2A6 mRNA compared to the vehicle control while CYP2A6 mRNA did not change after treatment with 1 μg/mL bilirubin, corresponding to physiologically normal level. No significant change of mRNA expression by 40 μg/mL bilirubin treatment was observed for CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4 and CYP3A5, UGT1A1, UGT1A3, UGT1A6, UGT2B4, UGT2B7, UGT2B10 and UGT2B15, constitutive androstane receptor (CAR), pregnane X receptor (PXR), retinoid X receptor α (RXRα) and hepatocyte nuclear factor-4α (HNF-4α). The induction profile of bilirubin was different from that of rifampicin, a typical PXR activator. This study demonstrated that CYP2A6 can be induced by bilirubin in a concentration dependent manner. 展开更多
关键词 CYP2A6 hepatocyteS HYPERBILIRUBINEMIA RT-PCR
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MRI联合CEA、CYFRA21-1检测对早期肺癌的诊断价值
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作者 刘冰玉 《罕少疾病杂志》 2024年第5期48-49,57,共3页
目的分析磁共振成像(MRI)联合癌胚抗原(CEA)、胞角蛋白19片段抗原2l-1(CYFRA21-1)用于早期肺癌的临床诊断价值。方法选取2018年4月到2020年11月我院疑似早期肺癌患者69例作为研究对象,均行MRI、CEA、CYFRA21-1检测。以病理学检测为“金... 目的分析磁共振成像(MRI)联合癌胚抗原(CEA)、胞角蛋白19片段抗原2l-1(CYFRA21-1)用于早期肺癌的临床诊断价值。方法选取2018年4月到2020年11月我院疑似早期肺癌患者69例作为研究对象,均行MRI、CEA、CYFRA21-1检测。以病理学检测为“金标准”。统计MRI、CEA、CYFRA21-1单独检测和三者联合诊断的诊断结果、诊断效能,对比不同病理结果血清CEA、CYFRA21-1水平、不同病理类型血清CEA、CYFRA21-1水平、不同影像学特征血清CYFRA21-1水平。结果本组69例疑似早期肺癌患者,病理学检查确诊阳性35例,阴性34例;MRI诊断出真阳性、真阴性分别为28例、27例;CEA诊断出真阳性、真阴性分别为23例、29例;CYFRA21-1诊断出真阳性、真阴性均为22例、22例;三者联合诊断真阳性、真阴性分别为32例、30例。三者联合诊断灵敏度91.43%、准确度89.86%均明显高于MRI 80.00%、79.71%,CEA 65.71%、75.36%,CYFRA21-162.86%、63.77%(P<0.05)。肺癌患者血清CEA、CYFRA21-1水平明显高于非肺癌患者(P<0.05);鳞癌患者血清CEA、CYFRA21-1水平明显高于腺癌患者、小细胞肺癌(P<0.05);存在淋巴结转移、病灶>3cm、存在分叶征的血清CYFRA21-1水平者明显高于无淋巴结转移、病灶≤3cm、无分叶征者(P<0.05)。结论MRI联合CEA、CYFRA21-1检测早期肺癌可提高诊断灵敏度与准确度,可用于临床评估病理类型,且不同影像学特征CYFRA21-1表达存在显著差异,可为疾病确诊提供更客观、全面的信息支持。 展开更多
关键词 肺癌 早期 磁共振成像 癌胚抗原 胞角蛋白19片段抗原2l-1
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