玳玳果黄酮降脂提取物体内组织分布规律及特征研究

目的：建立UPLC-MS/MS分析方法同时测定玳玳果黄酮降脂提取物效应组分新橙皮苷和柚皮苷在大鼠10种脏器组织中含量，分布规律及特征。方法：采用UPLC-MS/MS技术建立提取物效应组分新橙皮苷及柚皮苷在大鼠心、肝、脾、肺、肾、脑、胃、小肠、脂质、肌肉组织中的定量分析方法；大鼠给药后分别于0.33，0.67，1，4，8 h的5个时间点，分别摘取以上10种脏器组织，测定脏器组织及血液中效应组分的质量浓度，采用DAS（V 2.0）药动学软件对各样本的药物浓度-时间数据进行房室拟合，并计算不同组织效应组分的药-时曲线下面积（AUC）及平均滞留时间（MRT）。结果：所建立的UPLC-MS/MS定量分析方法具备良好的专属性、标准曲线及线性范围良好、方法准确度与精密度、定量下限均符合有关规定；玳玳果黄酮降脂提取物效应组分在血液中的分布符合一室模型，除肾脏及脑组织外，其余脏器中提取物效应组分的房室特征多为静脉注射的二室模型，柚皮苷在肾脏中的拟合结果为非静脉注射的二室模型，新橙皮苷在脑组织拟合结果为静脉注射的三室模型，给药后8 h各组织中效应组分新橙皮苷及柚皮苷AUC值大小顺序均为小肠 > 胃 > 肾 > 脂质 ≈ 脾脏 > 肺 > 肌肉 > 肝 > 心 > 脑，效应组分在各脏器中均无明显蓄积；效应组分在血液、肾脏、肝脏中的滞留时间较长，MRT均大于2 h，脂质最短，MRT不足1 h；各脏器中新橙皮苷的药-时曲线下面积约是柚皮苷的3倍，而心、肝、肾中则是3.5，2.1和3.4倍。结论：玳玳果黄酮降脂提取物效应组分在大鼠组织中分布迅速，达峰时间早于血液；效应组分在肠道内消除缓慢，给药8 h后在各脏器中的含量均显著下降且无特异的蓄积部位。研究结果揭示玳玳果黄酮降脂提取物效应组分在大鼠体内的分布特征及规律，为进一步理解玳玳果黄酮降脂提取物在体内的作用靶点及机制奠定了基础。     

新生血管特异性结合肽GX1二聚体抑制胃癌新生血管生成的实验研究

目的:探讨新生血管特异性结合肽GX1二聚体对胃癌新生血管生成的影响。方法:化学合成GX1二聚体、GX1单体、对照肽二聚体，CCK-8实验、管状结构形成实验、迁移实验研究GX1二聚体对胃癌血管内皮细胞（co-HUVEC）增殖、微管形成、迁移能力的影响，流式细胞学技术分析其对细胞周期分布和凋亡的影响。结果:CCK-8结果显示，GX1二聚体与对照肽二聚体及PBS对照组相比，100~200 μmol/L可抑制co-HUVEC增殖，具有统计学差异（P<0.05），并呈剂量依赖性，GX1二聚体较单体抑制作用增强，并有统计学差异（P<0.05）。管状结构形成实验、细胞损伤迁移实验结果显示，与对照肽二聚体及对照组PBS 相比，GX1二聚体及GX1单体，均可抑制胃癌内皮细胞管状结构的形成及迁移，且二聚体抑制作用强于单体；对照肽二聚体仅有轻微的抑制胃癌内皮细胞管状结构的形成及迁移。流式细胞术分析显示，与对照肽二聚体及PBS对照组相比，GX1二聚体及GX1单体均可诱导细胞凋亡（P<0.05），且GX1二聚体的诱导作用强于GX1单体（P<0.05），而对细胞周期分布则无明显影响。结论:GX1二聚体和GX1单体均可抑制胃癌新生血管内皮细胞增殖、微管形成、迁移能力及诱导凋亡，且GX1二聚体较GX1单体作用增强。GX1二聚体有望代替单体成为胃癌新生血管靶向治疗小肽类药物。     

UPLC-Q-TOF-MS对桑白皮总黄酮提取物的快速分析

目的:对桑白皮总黄酮提取物中的各化合物进行快速的分离和鉴定,并对其主要的裂解碎片和二级裂解规律进行探讨。方法:采用超高效液相串联四级杆飞行时间质谱联用技术(UPLC-Q-TOF-MS),在电喷雾离子源(ESI)负离子模式下进行分离和检测;使用Waters公司BRH分析柱(2.1 mm×50 mm,1.7μm);以0.1%甲酸水为流动相A,乙腈为流动相B,梯度洗脱;流速0.3 m L·min~(-1);柱温为25℃。结果:基于UPLC-Q-TOF-MS技术分离所得精确相对分子质量,结合二级质谱裂解信息,使用Masslynx 4.1软件对数据进行统计和分析,并参考Sci Finder数据库(美国化学学会在线数据库学术版),桑白皮总黄酮提取物中共鉴定出13种黄酮成分,其中有7个Diels-Alder加合物,主要代表物为桑根酮C(sanggenon C),桑根酮D(sanggenon D),6种异戊烯基黄酮类化合物,代表物为桑辛素(morusin)。结论:通过超高效液相的分离,首次发现了桑白皮总黄酮提取物中的化合物在ESI源中脱去H_2和H_2O的现象,并对其二级裂解碎片的规律进行探讨,同时也为桑白皮总黄酮提取物的成分鉴定提供了一个快速、简便、可靠的方法。     

枣叶中黄酮类化合物含量及其动态变化

目的:研究新疆阿拉尔骏枣叶、灰枣叶、酸枣叶中芦丁、柚皮苷、野黄芩苷、橙皮苷、槲皮素、山柰酚含量在一个生长周期内的动态变化,确定适宜的采摘时期,为综合开发利用枣叶提供科学依据。方法:应用高效液相色谱法测定3种枣叶中6种黄酮类成分的含量及动态变化,采用cosmosil C18色谱柱(4.6 mm×250 mm,5μm),以乙腈(A)-0.2%甲酸水(B)溶液为流动相,梯度洗脱,体积流量1.0 m L·min~(-1),检测波长280 nm,柱温25℃。结果:6种黄酮类化合物均得到良好分离,线性关系良好(r≥0.999);所检测的6个黄酮苷类成分中质量分数范围分别为芦丁1.33~11.59 mg·g~(-1),柚皮苷0.35~3.51 mg·g~(-1),野黄芩苷0.61~1.74 mg·g~(-1),橙皮苷0.11~2.81 mg·g~(-1),槲皮素0.008~0.37 mg·g~(-1),山柰酚0.01~0.03 mg·g~(-1);不同品种枣叶中的黄酮类化合物成分含量不一样,发育阶段显著影响着枣叶片的黄酮类成分质量分数,在发芽期和花期比较高,果实成熟期降到最低。结论:建立的HPLC含量测定方法简便快速,结果准确可靠、重复性好;如果以利用枣叶黄酮类化合物为目的,可以在4月初采集枣叶芽,有望获得较高的得率。     

镰形棘豆黄酮苷元对免疫抑制小鼠细胞因子的影响

目的:研究藏药镰形棘豆黄酮苷元对免疫抑制小鼠细胞因子的影响。方法:将60只昆明种小鼠随机分为6组:空白组,模型组,镰形棘豆黄酮苷元高、中、低剂量组(336、168、84 mg/kg)和盐酸左旋咪唑组(25 mg/kg),每组10只。镰形棘豆黄酮苷元高、中、低剂量组分别灌胃不同剂量的黄酮苷元;盐酸左旋咪唑组灌胃左旋咪唑25 mg/kg;空白组和模型组灌服等体积5%吐温-80溶液,共10天。第8天开始注射环磷酰胺制备免疫低下小鼠模型,除空白组腹腔注射生理盐水外,其他各组分别腹腔注射环磷酰胺,共3天。采用酶免仪分别测定血清中白细胞介素1、2、4、8、10(IL-1、IL-2、IL-4、IL-8、IL-10),肿瘤坏死因子α(TNF-α),干扰素γ(IFN-γ)的含量及脾淋巴细胞培养上清液中IL-2、IL-4、IL-10、TNF-α、IFN-γ的含量,观察镰形棘豆黄酮苷元对免疫抑制小鼠细胞因子的影响。结果:与模型组比较,镰形棘豆黄酮苷元各剂量组能有效升高免疫抑制小鼠血清和脾淋巴细胞培养液中各细胞因子的含量,差异有统计学意义(P0.05)。结论:镰形棘豆黄酮苷元能够拮抗环磷酰胺所致小鼠的免疫抑制作用,增强小鼠的免疫功能。     

Diffusion of resin monomers through human carious dentin in vitro

Abstract The diffusion of 2-hydroxyethylmediacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA) from light cured bonding resin-composite resin restorations through human carious dentin was investigated. Extracted human molar teeth with different degrees of caries were obtained from consenting donors. Teeth were classified into three groups according to caries severity (mild, moderate and severe) using subjective criteria. The outer carious lesions were then removed guided by a proprietary caries detector dye. Teeth with exposure of the pulp space after caries removal were excluded from the study. A polypropylene chamber was attached to the cemento-enamel junction of each tooth to contain 1 ml distilled water. Each cavity was restored with a HEMA containing bonding resin then a TEGDMA-containing resin composite. Water samples were retrieved over a lime course and analyzed by high performance liquid chromatography. There was great variation between teeth in HEMA and TEGDMA permeability. The cumulative amounts released were of similar magnitude to those observed in non-carious teeth for the mild and moderately-severe groups. However, the cumulative amounts released were markedly greater in severely carious teeth than in those with moderate or mild caries.     

Effects of storage time and temperature on the properties of two self-etching systems

OBJECTIVES: To evaluate the micro-shear bond strength to enamel and dentin, pH and hardness of two self-etching adhesives over a period of 60 weeks storage at different temperatures. MATERIALS AND METHODS: Two self-etching systems, an all-in-one adhesive, Clearfil Tri-S Bond (TS) and a two-step adhesive, Clearfil SE Bond (SE) were used in this study (both by Kuraray Medical, Osaka, Japan). Their micro-shear bond strengths to enamel and dentin were measured. The materials were then stored at 4, 23 or 37 degrees C. Their bond strengths were measured again after 1, 4, 16 and 60 weeks and compared to the base line. The nano-indentation hardness of the polymerized bonding, pH of SE primer and TS were also measured at the baseline and after 60 weeks of storage at three different temperatures. Bond-strength and hardness data were analyzed using ANOVA and post hoc tests at the significance level of 0.05. RESULTS: Two-way ANOVA analysis showed that both storage conditions and material type had significant effects on bond strength to enamel or dentin but the interactions of these factors were not significant for any of the substrates. One-way ANOVA post hoc tests revealed that the bond strength of adhesives stored at 37 degrees C significantly decreased during the storage period; with the earliest significant decreases observed at 4 weeks for TS and at 16 weeks for SE. After 60 weeks of storage, the hardness obtained for SE bonding resin was not significantly different with that at the baseline for 4, 23 and 37 degrees C groups, but there was a significant decrease observed in hardness for TS stored at 37 degrees C, compared to that at the baseline. The pH of both self-etching materials decreased when they were stored at 37 degrees C. CONCLUSION: Storage time and temperature significantly affected the bond strength of both materials through the time dependent hydrolysis and other changes that are likely to occur in the water-containing self-etching agents at high temperatures.     

超声波协同复合酶提取菟丝子总黄酮工艺优化

目的:将酶解法和超声波法联用,通过工艺优化提高菟丝子总黄酮的含量。方法:实验采用紫外分光光度法测定总黄酮提取率,选取酶解pH、酶解温度和超声时间3个指标为影响因素,菟丝子总黄酮提取率为响应值,Design-Expert 8.0统计分析软件的响应面分析法安排试验后获得最适合工艺参数。结果:最适合的工艺参数是PH为4.0,酶解温度为52.6℃,超声时间为20.3 min,在此条件下得到的总黄酮质量分数为23.39 mg·g~(-1)。结论:此工艺操作简单、稳定性好、总黄酮提取率高,可为菟丝子总黄酮的相关工业生产提供技术支持。     

坤泰胶囊化学成分的LC-ESI-MS/MS分析

目的:建立坤泰胶囊中化学成分的高效液相色谱-电喷雾质谱联用技术(HPLC-ESI-MS/MS)并对其化学成分进行初步鉴定。方法:采用LC-ESI-MS/MS对坤泰胶囊进行成分分析与鉴定,选用C_(18)色谱柱(4.6 mm×150 mm,5μm),以乙腈-0.1%甲酸水溶液为流动相梯度洗脱,流速1.0 mL·min~(-1),柱温30℃。质谱使用电喷雾(ESI)离子源,正离子模式采集数据。质量扫描范围为m/z 50~1 500。对各色谱峰质谱图进行分析,根据准分子离子峰判断相对分子质量,进一步根据各主要碎片离子、紫外光谱、保留时间等信息,与文献数据进行比较推测化合物的结构。结果:从坤泰胶囊中鉴定了21个化合物,主要为黄酮类化合物和生物碱类化合物,并对化合物的药材来源进行了归属。其中,主要有来自黄芩的黄芩苷、汉黄芩苷、黄芩素、汉黄芩素等,来自黄连的巴马汀、小檗碱、黄连碱、药根碱、非洲防己碱、木兰花碱等,来自白芍的芍药苷等。结论:采用LC-ESIMS/MS能够对坤泰胶囊中主要成分进行快速分析与鉴定,为坤泰胶囊进一步开展指纹图谱、质量控制、药物代谢研究和谱效关系研究奠定了基础。     

Dietary Bioactives: Establishing a Scientific Framework for Recommended Intakes

In the United States, dietary reference intakes describe the relations between nutrient intakes and indicators of adequacy, prevention of disease, and avoidance of excessive intakes among healthy populations for essential nutrients but not dietary bioactive components (DBCs), whose absence from the diet is presumably not deleterious to health (i.e., does not cause a deficiency syndrome). An appropriate framework is needed for establishing recommended intakes for which public health messages and food labeling for DBCs can be derived, because their putative health benefits may not be readily defined in the context of nutritional essentiality. In addition, a myriad of factors make determining their intake and status and investigating their discrete contributions to health particularly challenging. Therefore, the ASN Dietary Bioactive Components Research Interest Section felt it worthwhile to convene a special “hot topic” session at the 2014 Experimental Biology meeting to discuss this issue and serve as a call for future scientific dialogue on establishing a framework for recommended intakes of DBCs. This session summary captures the discussions and presentations that transpired during this session.