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1.
目的 通过观察黄芩苷对乳腺癌组织毛细血管通透性(Capillary Vessel Permeability,CVP)、赖氨酰氧化酶(Lysyl Oxidase,LOX)及血清丙二醛(Malondialdehyde,MDA)等相关指标的影响,探讨黄芩苷可能的抗乳腺癌作用机制。方法 通过在裸鼠皮下接种MDA-MB-231乳腺癌细胞株建立乳腺癌移植瘤模型;实验分为模型组、黄芩苷组、阿霉素组、黄芩苷+阿霉素组。于接种第7日开始:黄芩苷组每天灌胃黄芩苷水溶液(100 mg·kg-1),连续14天;阿霉素组每3天腹腔注射一次阿霉素(5mg·kg-1),共用药5次;模型组每天灌胃生理盐水(10 mL·kg-1),连续14天;黄芩苷+阿霉素组每天灌胃黄芩苷水溶液(100 mg·kg-1),连续14天,并每3天腹腔注射一次阿霉素5 mg·kg-1,共5次。给药期间监测移植瘤体积;紫外可见分光光度计620 nm下测OD值来反映黄芩苷对肿瘤毛细血管通透性的影响;硫代巴比妥酸(Thiobarbituric acid,TBA)比色法检测黄芩苷对裸鼠血清中丙二醛(MDA)的影响;免疫组化染色法检测乳腺癌组织中赖氨酰氧化酶(LOX)的表达情况。结果 ①与模型组比较,黄芩苷组、阿霉素组、黄芩苷+阿霉素组瘤体重量均明显减轻(P<0.05);黄芩苷+阿霉素组瘤体重量较阿霉素组明显减轻(P<0.05)。②与模型组比较,黄芩苷组降低乳腺癌组织毛细血管的通透性,而阿霉素组则增加肿瘤组织中毛细血管的通透性,差异均具有统计学意义(P<0.05)。③黄芩苷组能够明显抑制荷瘤裸鼠血清MDA的表达,与模型组比较差异有显著统计学意义(P<0.01);阿霉素组促进MDA的表达,与模型组比较差异有统计学意义;黄芩苷+阿霉素组促进MDA的表达,与模型组比较差异无统计学意义。④与模型组比较,黄芩苷组裸鼠乳腺癌组织LOX的表达显著下调(P<0.01),阿霉素组肿瘤组织中LOX表达增加(P<0.05);黄芩苷+阿霉素组能下调裸鼠乳腺癌组织LOX的表达,与模型组比较差异无统计学意义。结论 黄芩苷能够明显抑制乳腺癌移植瘤的生长,其机制可能与黄芩苷降低肿瘤组织毛细血管的通透性,抑制裸鼠血清中丙二醛、乳腺癌组织中赖氨酰氧化酶的表达,从而改变肿瘤缺氧微环境有关。  相似文献   
2.
Hypoxia-induced chemoresistance is a major obstacle in the development of effective cancer therapy. In our study, the reversal abilities of NADPH oxidase 4 (NOX4) silence on hypoxia resistance and the potential mechanism were investigated. Our data showed that the expression of NOX4 was upregulated in human neuroblastoma cells SH-SY5Y under hypoxia condition time dependently. Knockdown of NOX4 expression by siRNA inhibited glycolysis induced by hypoxia through decreasing the expression of glycolysis-related proteins (HIF-1 , LDHA, and PDK1), decreasing glucose uptake, lactate production, and ROS production, while increasing mitochondria membrane potential. Moreover, NOX4 silence inhibited cell growth under hypoxia condition through suppressing cell proliferation and proliferation-related proteins (Ki-67 and PCNA) compared with the hypoxia 24 h+siRNA NC group. Further, Western blot experiments exhibited that NOX4 siRNA could downregulate the rate of p-Akt/Akt. Treatment with PI3K/Akt signaling activator IGF-1 blocked, while treatment with Akt inhibitor perifosine enhanced the inhibitory effect of si-NOX4 on glycolysis and cell growth. In summary, knockdown of NOX4 had the ability of reversing hypoxia resistance, and the major mechanism is considered to be the inhibition of glycolysis and cell growth via the PI3K/Akt signaling pathway. Therefore, NOX4 could be a novel target against hypoxia resistance in neuroblastoma.  相似文献   
3.
目的:通过研究NADPH氧化酶4(NOX4)在胃癌(STAD)组织中的表达及其与临床病理学参数的相关性,阐明其在STAD预后中的重要作用。方法:运用GEPIA大数据分析NOX4在正常胃组织和胃癌组织中的表达差异和其对胃癌预后的影响。再运用LinkedOmics大数据分析NOX4与STAD临床病理学参数和胃癌临床分期的相关性。结果:数据库分析结果表明,与正常胃组织相比NOX4在胃癌组织中的表达显著提高,并且NOX4的表达量与胃癌T分期和临床分期呈显著正相关性,此外NOX4高表达组的胃癌患者总生存率显著低于NOX4低表达组的胃癌患者(P<0.05)。结论:NOX4是胃癌的一种重要的不良预后指标,高表达的NOX4预示着胃癌的高恶性等级和不良预后。  相似文献   
4.

Introduction

Cigarette smoking is a major risk factor in the development of chronic obstructive pulmonary disease (COPD). Serotonin levels have been associated with COPD and smoking has been as a significant modulator. Elevated levels of serotonin are responsible for bronchoconstriction and pulmonary vasoconstriction and also nicotine dependence, thus serotonin response could be affected by genetic polymorphisms in transporters and receptors of serotonin.

Objectives

The aim of the current study was to analyze the effect of SLC6A4 (5HTT_LPR) (rs25531) and HTR2A-1438G/A (rs6311) genetic polymorphisms on the relation between smoking habits and COPD.

Methods

The association between SLC6A4 (5HTT_LPR) (rs25531), HTR2A-1438G/A (rs6311), smoking degree and COPD was analyzed in a total of 77 COPD patients (active smokers) and 90 control subjects (active healthy smokers). The DNA was extracted of peripheral leukocytes samples and genotyping was performed using an allele specific polymerase chain reaction.

Results

The distribution of SLC6A4 genotypes did not vary between healthy smokers and COPD patients (P = 0.758). On the other hand, the A allele of HTR2A (rs6311) was significantly associated with COPD incidence in the trend model (P = 0.02; 1.80 [1.04–3.11]). Among all smokers, this allele was also associated with the number of pack years smoked (P = 0.02) and also, we observed a marginal association with FEV1/FVC values (P = 0.06).

Conclusion

Our results point a possible role of the A allele of HTR2A (rs6311) in COPD pathogenesis, suggesting that this effect depends partly on tobacco consumption due to a gene-by-environment interaction.  相似文献   
5.
6.
目的 采用药效团及文献挖掘技术,筛选中草药中天然黄嘌呤氧化酶抑制剂(xanthine oxidase inhibitor,XOI),并研究其分布情况。方法 采用基于药效团的虚拟筛选和数据挖掘技术,在23 033个中药天然产物中筛选潜在的XOI。通过吸收、分布、代谢和排泄性质及药效团初步筛选具有潜在黄嘌呤氧化酶(xanthine oxidase,XO)抑制活性的化合物;使用分子对接技术进一步筛选XOI并选取打分较高的化合物,分析作用机制;采用数据挖掘方法分析潜在XOI化合物在中草药中的分布规律。结果 通过HypoGen方法构建了XOI药效团模型,筛选得到165个潜在活性化合物。通过分子对接技术进一步筛选,得到化合物102个,结果显示这些化合物主要是萜类,分布在见霜黄、慈竹、佩兰等中草药中,这些中草药以菊科药用植物为主,药味以辛、苦为主,药性多寒、温,多归于肝、肺经。选取排名前5的化合物进行作用模式分析,结果显示其与受体XO有较强的亲和作用,有进一步实验验证的价值。结论 在菊科植物及其亲缘关系比较接近的药用植物当中,可能发现潜在的天然XOI化合物,为探索新型XOI先导化合物提供参考。  相似文献   
7.
《Brain & development》2021,43(10):1023-1028
BackgroundAromatic L-amino acid decarboxylase (AADC) deficiency, caused by a pathogenic variant in the dopa decarboxylase (DDC) gene, is a rare neurometabolic disorder in which catecholamine and serotonin are not synthesized. From a large number of reports, it has been recognized that most affected patients show severe developmental delay in a bedridden state and are unable to speak. On the other hand, patients with a mild phenotype with AADC deficiency have been reported, but they number only a few cases. Therefore, the variation of phenotypes of the disease appears to be broad, and it may be challenging to diagnose an atypical phenotype as AADC deficiency.Case reportWe report novel compound heterozygous variants in DDC (c.202G > A and c.254C > T) in two sisters, whose main complaint was mild developmental delay, by whole-exome sequencing (WES). Additionally, we describe their clinical features and provide an image that shows the variants located at different sites responsible for the catalysis of AADC in a three-dimensional structure. The patients were prescribed a Monoamine oxidase (MAO) inhibitor after diagnosis.InterpretationOur cases indicate that a comprehensive genomic approach helps to diagnose AADC deficiency with atypical features, and underscore the significance of understanding the variations of this disorder for diagnosis and appropriate treatment.  相似文献   
8.
目的 制备载四苯基卟啉锌(TPZ)、葡萄糖氧化酶(GOD)与全氟戊烷的超声响应性纳米粒子(NP)TPZ-GOD NP,并评估其超声/光声双模态成像效果及介导声动力治疗(SDT)联合饥饿治疗小鼠结直肠癌的效果。方法 以薄膜水化法制备载TPZ及GOD的NP。观察TPZ-GOD NP基本特性,以紫外分光光度计检测其超声辐照下释放GOD量,以流式细胞仪检测结直肠癌CT-26细胞与TPZ-GOD NP共同孵育后细胞吞噬情况,于荧光显微镜下观察超声辐照后TPZ-GOD NP细胞毒性活性氧产生情况。检测TPZ-GOD NP增强体内外超声/光声双模态成像效果;观察TPZ-GOD NP介导SDT、饥饿治疗及二者联合对移植瘤小鼠模型的作用。结果 成功制备TPZ-GOD NP,颗粒呈球形,大小均一,平均粒径(262.10±62.92)nm。超声辐照后,GOD释放量随时间而增加。TPZ-GOD NP可被CT-26细胞吞噬,超声辐照后可产生大量细胞毒性活性氧;可发生液气相变,增强体内外超声造影效果。体外光声成像显示,TPZ-GOD NP光声信号值随浓度而呈线性增加。经尾静脉注射TPZ-GOD NP后,小鼠肿瘤区域内光声信号明显增强;SDT或饥饿治疗均可杀伤部分CT-26细胞,二者联合效果更佳。结论 制备TPZ-GOD NP具有超声响应性,可用于超声/光声双模态成像引导下声动力联合饥饿治疗小鼠结直肠癌。  相似文献   
9.
目的 为筛选高活性的蛇足石杉铜胺氧化酶(copper-containing amine oxidase,CAO),通过生物工程方法实现石杉碱甲(huperzine A,HupA)的合成、为加快新药创制进度提供理论依据。方法 基于蛇足石杉转录组测序得到的CAO序列片段,利用cDNA末端快速扩增技术(rapid amplification of cDNA ends,RACE)技术,扩增、拼接并验证获得该基因的全长cDNA序列,并将其命名为HsCAO2结果 通过RACE技术得到HsCAO2的cDNA全长为2696 bp,CDS为2199 bp,编码732个氨基酸。氨基酸序列同源性比对发现,HsCAO2具有保守的氨基酸位点和Cu2+结合位点;进化树分析结果表明,HsCAO2与蛇足石杉中的另一个CAO(HsCAO1)同源性最高,达91.67%;蛋白质结构分析结果表明,HsCAO2也可能在生物体里以同源二聚体的形式存在。在此基础上,进一步分别构建了超表达载体pOX-HsCAO2和体外蛋白表达载体pET-28a (+)-HsCAO2。结论 HsCAO2很可能是蛇足石杉中的一个新的功能性CAO,且超表达载体和体外蛋白表达载体的成功构建为进一步研究其功能奠定了基础。  相似文献   
10.
Peroxisomal acyl-CoA oxidase (ACOX1) deficiency is a rare autosomal recessive single enzyme deficiency characterized by hypotonia, seizures, failure to thrive, developmental delay, and neurological regression starting from approximately 3 years of age.Here, we report two siblings with ACOX1 deficiency born to non-consanguineous Japanese parents. They showed mild global developmental delay from infancy and began to regress at 5 years 10 months and 5 years 6 months of age respectively. They gradually manifested with cerebellar ataxia, dysarthria, pyramidal signs, and dysphasia. Brain MRI revealed T2 high-intensity areas in the cerebellar white matter, bilateral middle cerebellar peduncle, and transverse tracts of the pons, followed by progressive atrophy of these areas.Intriguingly, the ratios of C24:0, C25:0, and C26:0 to C22:0 in plasma, which usually increase in ACOX1 deficiency were within normal ranges in both patients. On the other hand, whole exome sequencing revealed novel compound heterozygous variants in ACOX1: a frameshift variant (c.160delC:p.Leu54Serfs*18) and a missense variant (c.1259 T > C:p.Phe420Ser). The plasma concentration of individual very long chain fatty acids (C24:0, C25:0, and C26:0) was elevated, and we found that peroxisomes in fibroblasts of the patients were larger in size and fewer in number as previously reported in patients with ACOX1 deficiency. Furthermore, the C24:0 β-oxidation activity was dramatically reduced.Our findings suggest that the elevation of individual plasma very long chain fatty acids concentration, genetic analysis including whole exome analysis, and biochemical studies on the patient’s fibroblasts should be considered for the correct diagnosis of ACOX1 deficiency.  相似文献   
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