基于UHPLC-MS/MS的药用植物内源性激素含量检测方法及黄花蒿不同器官激素的测定

目的 激素是调控植物活性次生代谢产物合成途径的核心调控因子，内源激素结构多样、含量极低，检测难度高，缺乏高效、准确的检测方法。本研究利用超高效液相色谱串联质谱（UHPLC-MS/MS）技术构建了对黄花蒿中茉莉酸、细胞分裂素、赤霉素、生长素、脱落酸等多类植物内源性激素高效定量检测方法。方法 使用Agilent Poroshell 120 EC-C18（2.7 μm， 3.0×150 mm）色谱柱，流动相为0.05%甲酸水-乙腈溶液，梯度洗脱，采用多反应监测模式验证方法可行性，并对黄花蒿不同器官中植物激素进行定量分析。结果 本方法中检测的16种植物激素均呈良好线性，加样回收率、精密度和稳定性均符合植物样品的测定要求。利用此方法测定青蒿不同器官的激素含量，结果表明脱落酸、茉莉酸、茉莉酸甲酯均在叶中含量较高，赤霉素和生长素在根部含量高，细胞分裂素在叶和茎中含量高。结论 青蒿不同器官的激素测定结果可进一步印证脱落酸、茉莉酸、茉莉酸甲酯在调控青蒿素合成中起着重要作用的相关报道，同时表明该方法检测性良好。本文构建的植物内源性激素的检测方法为进一步探究植物生长发育、抵御外界胁迫的相关机制及次生代谢产物的合成等方面提供了手段。     

基于代谢组学分析的18-三体妊娠羊水差异代谢物

摘要:目的通过 非靶向代谢组学方法分析18-三体( trisomy 18,T18) 妊娠母体羊水样本,探索其差异代谢物。方法采用病 例-对照研究,以8例18-三体妊娠母体羊水样本为病例组,40例正常胎儿母体羊水样本为对照组,采用气相色谱飞行时间质 谱技术( GC-T0F/MS)检测两组羊水样本。采用主成分分析(PCA)和正交偏最小二乘法判别分析(OPIS-DA)模型分析代谢谱 差异,通过单维统计分析寻找差异代谢物。结果PCA 和OPLS-DA模型分析均显示病例组与对照组之间无明显分离趋势。 通过单维分析在两组间共发现5种差异代谢物,分别为甘油醛、葡萄糖酸、硫酸吲哚酚.磷酸盐和泛酸(P<0.05)。结论羊水 代谢组学证实18-三体妊娠存在多种代谢物水平的差异,为疾病的发生机制的探索提供了更多研究思路。     

不同病理分级的胰腺神经内分泌肿瘤的MRI征象对比分析及“主胰管绕道征”的诊断价值探讨

目的:对比分析G1、G2级胰腺神经内分泌肿瘤（pNEN）的MRI征象，探讨“主胰管绕道征”的诊断价值。方法:收集32例pNEN患者的临床资料，以术后病理学检查为金标准，定量分析G1、G2级临床指标及影像学指标的差异，并着重分析pNEN与主胰管的关系。结果:32例患者中，病理分级G1、G2、G3级的患者分别有12例、16例、4例，分别以胰尾、胰头、胰颈为主要发生部位。与G1级神经内分泌瘤（NET）相比，G2级NET肿瘤直径显著增大，不规则形态的病灶增多，边缘模糊，生物学行为出现明显恶性倾向，主胰管扩张、胰腺外侵犯及淋巴结/肝转移的发生率升高。G1级NET的MRI平扫信号均质程度高于G2级（P＜0.05），但二者在增强MRI扫描的各个期象信号强度均无明显差异（P＞0.05）。28例NET患者中，22例（78.6%）出现主胰管绕道征；神经内分泌癌（NEC）患者无一例出现此征象。术前，28例NET的诊断准确率为78.6%（22/28），存在6例误诊，其中，3例误诊为胰腺癌，2例误诊为囊腺瘤（癌），1例误诊为胰腺假性囊肿。在原MRI诊断依据的基础上纳入“主胰管绕道征”，诊断准确率提高至89.3%（25/28），但仍存在3例误诊，其中2例误诊为囊腺瘤（癌），1例误诊为胰腺假性囊肿，排除了胰腺癌的误诊。结论:MRI对鉴别诊断良恶性pNEN有较高的准确性，但对部分G1与G2级NET仍存在一定的误诊率，主胰管绕道征可帮助减少出现胰腺癌误诊。     

Exact penalty functions for optimal control problems I: Main theorem and free‐endpoint problems

In this two‐part study, we develop a general approach to the design and analysis of exact penalty functions for various optimal control problems, including problems with terminal and state constraints, problems involving differential inclusions, and optimal control problems for linear evolution equations. This approach allows one to simplify an optimal control problem by removing some (or all) constraints of this problem with the use of an exact penalty function, thus allowing one to reduce optimal control problems to equivalent variational problems and apply numerical methods for solving, eg, problems without state constraints, to problems including such constraints, etc. In the first part of our study, we strengthen some existing results on exact penalty functions for optimisation problems in infinite dimensional spaces and utilise them to study exact penalty functions for free‐endpoint optimal control problems, which reduce these problems to equivalent variational ones. We also prove several auxiliary results on integral functionals and Nemytskii operators that are helpful for verifying the assumptions under which the proposed penalty functions are exact.     

A graph model of combination therapies

The simultaneous use of multiple medications causes drug–drug interactions (DDI) that impact therapeutic efficacy. Here, we argue that graph theory, in conjunction with game theory and ecosystem theory, can address this issue. We treat the coexistence of multiple drugs as a system in which DDI is modeled by game theory. We develop an ordinary differential equation model to characterize how the concentration of a drug changes as a result of its independent capacity and the dependent influence of other drugs through the metabolic response of the host. We coalesce all drugs into personalized and context-specific networks, which can reveal key DDI determinants of therapeutical efficacy. Our model can quantify drug synergy and antagonism and test the translational success of combination therapies to the clinic.     

Identification of key genes and pathways in discoid lupus skin via bioinformatics analysis

Discoid lupus erythematosus (DLE) is the most common skin manifestation of lupus; however, the molecular mechanisms underlying DLE remain unknown. Therefore, we aimed to identify key differentially expressed genes (DEGs) in discoid lupus skin and investigate their potential pathways.To identify candidate genes involved in the occurrence and development of the disease, we downloaded the microarray datasets {"type":"entrez-geo","attrs":{"text":"GSE52471","term_id":"52471"}}GSE52471 and {"type":"entrez-geo","attrs":{"text":"GSE72535","term_id":"72535"}}GSE72535 from the Gene Expression Database (GEO). DEGs between discoid lupus skin and normal controls were selected using the GEO2R tool and Venn diagram software (http://bioinformatics.psb.ugent.be/webtools/Venn/). The Database for Annotation, Visualization, and Integrated Discovery (DAVID), Enrichr, and Cytoscape ClueGo were used to analyze the Kyoto Encyclopedia of Gene and Genome pathways and gene ontology. Protein-protein interactions (PPIs) of these DEGs were further assessed using the Search Tool for the Retrieval Interacting Genes version 10.0.Seventy three DEGs were co-expressed in both datasets. DEGs were predominantly upregulated in receptor signaling pathways of the immune response. In the PPI network, 69 upregulated genes were selected. Furthermore, 4 genes (CXCL10, ISG15, IFIH1, and IRF7) were found to be significantly upregulated in the RIG-I-like receptor signaling pathway, from analysis of Enrichr and Cytoscape ClueGo.The results of this study may provide new insights into the potential molecular mechanisms of DLE. However, further experimentation is required to confirm these findings.     

Endoscopic diagnosis of sessile serrated polyp: A systematic review

The aim of the present review was to clarify how we should detect and diagnose sessile serrated polyps (SSP) endoscopically. A systematic search was conducted of MEDLINE from January 2004 through March 2018. Nine findings: (i) proximal location; (ii) size >10 mm; (iii) irregular shape; (iv) indistinctive border; (v) cloud‐like surface; (vi) mucus cap; (vii) rim of debris in white‐light endoscopy; (viii) dilated vessels; and (ix) dilated crypts (pits) in image‐enhanced endoscopy were considered to be candidate discriminators of SSP from hyperplastic polyps. Prospective studies in a general setting are warranted to validate the above‐mentioned endoscopic features of SSP during real‐time colonoscopy and to determine whether these features are useful for the differential diagnosis of SSP.