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1.
目的 建立三棱化学成分的超高效液相色谱-紫外法(UPLC-UV)特征图谱,并对主要特征峰进行指认。方法 色谱柱为Waters ACQUITY UPLC HSS T3柱(100 mm×2.1 mm,1.8 μm),流动相为乙腈-0.1%磷酸水溶液,线性梯度洗脱,双波长切换检测,0~12 min为300 nm,12~16 min为240 nm,测定10批三棱药材UPLC-UV图,确定共有特征峰并计算相似度,利用对照品及超高效液相色谱-四极杆飞行时间质谱法(UPLC-Q/TOF-MS)对主要特征峰进行指认。结果 采集了10批三棱药材UPLC-UV指纹图谱,确定11个特征峰,相似度均大于0.9,认定了9个特征峰,其中通过对照品指认了咖啡酸、对羟基苯甲酸、对香豆酸,通过质谱解析指认了2个苯丙素乙酰蔗糖酯、3个苯丙素甘油酯及首次在三棱中发现的三棱酮。结论 建立了三棱UPLC-UV特征图谱,能够表征不同结构类型的三棱化学成分,为三棱药材质量控制提供了参考。  相似文献   
2.
DINCH (cyclohexane-1,2-dicarboxylic acid-diisononyl ester) is a phthalate plasticizer substitute introduced into the market in 2002. It is increasingly used especially in the production of toys, food contact materials and medical devices. In this measurement campaign on 24-h urine samples of young adults (20–29 years) from the German Environmental Specimen Bank (ESB) collected in 2010, 2011, 2013, 2015 and 2017 (in total 300 samples, 60 samples/year) we analyzed three specific, oxidized DINCH metabolites (OH-MINCH: cyclohexane-1,2-dicarboxylic acid-mono(hydroxy-isononyl) ester; cx-MINCH: cyclohexane-1,2-dicarboxylic acid-mono(carboxy-isooctyl) ester, oxo-MINCH: cyclohexane-1,2-dicarboxylic acid-mono(oxo-isononyl) ester). We merged these data with earlier data of the ESB from the years 1999–2012 and are now able to report levels and time trends of internal DINCH exposure from 1999 to 2017.After first detections of the major oxidized DINCH metabolite OH-MINCH in 2006 (6.7%) detection rates rapidly increased to 43.3% in 2009, 80% in 2010 and 98.3% in 2011 and 2012. From the year 2013 on we could detect OH-MINCH in every urine sample analyzed. The median concentrations of OH-MINCH rapidly increased from 0.15 μg/L in 2010 to twice the concentration in 2011 (0.31 μg/L) with further increases in 2013 (0.37 μg/L), 2015 (0.59 μg/L) and 2017 (0.70 μg/L). Similar increases, albeit at lower detection rates and concentration levels, could be observed for cx-MINCH and oxo-MINCH. All metabolites strongly correlate with each other.For the ESB study population, DINCH exposures are still far below health based guidance values such as the German Human Biomonitoring Value (HBM-I; 4,500 μg/L for the sum of OH-MINCH and cx-MINCH) or the tolerable daily intake (TDI) of EFSA (1 mg/kg bw/d). The median daily DINCH intake (DI) calculated for 2017 was 0.23 μg/kg bw/d, thus 4,310-times lower than the TDI. The maximum DI calculated for one individual in 2012 (42.60 μg/kg bw/d) was a factor of more than 20 below the TDI.The ongoing increase in DINCH exposure needs to be closely monitored in the future, including populations with potentially higher exposures such as children. This close monitoring will enable timely exposure and risk reduction measures if exposures reached critical levels, or if new toxicological data lead to lower health based guidance values. DINCH belongs to the European Human Biomonitoring Initiative (HBM4EU) priority substances for which policy relevant questions still have to be answered.  相似文献   
3.
The nonsteroidal anti-inflammatory drugs elevate cardiovascular risk, perhaps, due to their accumulation in the heart and kidneys. We designed nanodelivery systems for cardiotoxic diclofenac to reduce its presence in these organs. Diclofenac ethyl ester (DFEE) was encapsulated in traceable micelles based on poly(ethylene oxide)-b-poly(ε-caprolactone) (DFEE-PCL-TM) or poly(ethylene oxide)-b-poly(α-benzyl carboxylate-ε-caprolactone) (DFEE-PBCL-TM). Diclofenac pharmacokinetics and tissue distribution were studied after intravenous (iv) and intraperitoneal administration of the nanoformulations and compared with those after iv doses of free diclofenac (n = 3-6/group). The average diameters for DFEE-PBCL-TM and DFEE-PCL-TM were 37.2 ± 0.06 and 45.1 ± 0.06 nm, respectively. Drug concentration dropped below the assay sensitivity after free drug administration in 6 h, but persisted for 24 h following DFEE-PBCL-TM (2.3 ± 1.4 μg/mL) and DFEE-PCL-TM (1.9 ± 0.6 μg/mL) iv administration. The diclofenac heart:blood and kidney:blood ratios were 5- to 12-fold lower with the nanoformulations than with free diclofenac. Near-infrared fluorescence measurements in tissues suggested exposure patterns to nanocarriers parallel with those achieved for delivered diclofenac by nanoformulations. Administration of DFEE-PCL-TM by iv or intraperitoneal injection, resulted in comparable pharmacokinetics and 6 h postdose near-infrared fluorescence in the heart, kidneys, liver, and spleen. When compared to each other, DFEE-PBCL-TM showed significantly lower diclofenac levels in the heart compared to DFEE-PCL-TM (0.3 ± 0.03 vs. 0.5 ± 0.1 μg/g). Developed nanoformulations of diclofenac prolonged diclofenac circulation and reduced its presence in the heart and kidneys, strongly suggesting cardiac-safe delivery vehicles for diclofenac.  相似文献   
4.
【摘要】 追踪T细胞数量和功能的变化在临床诊断和评估过敏原免疫治疗疗效等方面具有重要的参考价值。本文综述了羧基荧光素琥珀碱亚胺酯连续稀释法、酶联免疫斑点检测法、胞内细胞因子染色法和微阵列免疫传感器等过敏原特异性T细胞检测方法和临床应用的研究进展,为选择和发展合适的检测方法并应用于临床提供参考。  相似文献   
5.
Central Illustration. Pathophysiological pathways providing a causal link between high plasma concentrations of lipoprotein(a) (Lp(a)) and atherosclerotic vascular disease and aortic valve stenosis (AVS). Clinical outcomes are related to accelerated atherosclerosis complicated by atherothrombosis (myocardial infarction, stroke), peripheral artery disease (PAD) or aortic valve replacement (AVR) caused by valve calcification and aortic stenosis. Apo(a): apolipoprotein(a); LDL: low-density lipoprotein; OxPL: oxidized phospholipids; NSFA: Nouvelle Société Francophone d’Athérosclérose; SP: serine-protease domain; V: plasminogen kringle V (reproduced with permission).
  相似文献   
6.
葛雯  李海波  王振中  于洋  苏真真  杨彪  曹亮  黄文哲  肖伟  姚新生 《中草药》2019,50(17):4189-4199
目的 研究中药复方热毒宁注射液解热抗炎活性部位的化学成分。方法 采用脂多糖(LPS)诱导小鼠内毒素休克模型对热毒宁注射液解热抗炎活性部位进行筛选,综合应用HP-20大孔树脂、硅胶、MCI、ODS柱色谱以及反相MPLC、HPLC等各种现代色谱技术对解热抗炎活性部位进行系统的分离纯化,根据化合物的光谱数据和理化性质进行结构鉴定。采用LPS诱导小鼠巨噬细胞RAW264.7模型,以抑制炎性细胞因子前列腺素E2(PGE2)的分泌为评价指标对分离得到的化合物进行体外抗炎活性评价。结果 热毒宁注射液经大孔吸附树脂95%乙醇洗脱部位为解热抗炎活性部位,从中分离得到了24个化合物,分别鉴定为 (4aS,7aS,7bS)-4,4a,7a,7b-tetrahydro-2H-1,7-dioxacyclopent[cd] indene-5-carboxylic acid methyl ester(1)、(4aS,7aS)-1,4a,5,7a-tetrahydro-7-(hydroxymethyl)-cyclopenta[c] pyran-4-carboxylic acid methyl ester(2)、3α,5α-tetrahydrodeoxycordifoline lactam(3)、R-(Z)-4-甲基-5-[(2'',6'',6''-三甲基-4''-氧代-2''-环己烯-1''-基) 亚甲基]-2(5H)-呋喃酮(4)、(1α,2α,3β,4β)-2,4-双 (4-羟基-3-甲氧基苯基)-1,3-环丁烷二甲酸(5)、4-[(6-O-苯甲酰基-β-D-吡喃葡萄糖基) 氧基]-3-甲氧基苯甲酸(6)、丁香脂素(7)、E-3-(3,4-二羟基苯亚甲基)-5-(3,4-二羟基苯基) 二氢呋喃-2-酮(8)、6,7-二甲氧基香豆素(9)、7-羟基-6-甲氧基香豆素(10)、水杨酸(11)、丁香醛(12)、苯乙酸(13)、香草醛(14)、咖啡酸(15)香草乙酮(16)、3,5-O-二咖啡酰奎宁酸(17)、4,5-O-二咖啡酰奎宁酸(18)、3,4-O-二咖啡酰奎宁酸甲酯(19)、3,5-O-二咖啡酰奎宁酸甲酯(20)、4,5-O-二咖啡酰奎宁酸甲酯(21)、5-O-咖啡酰奎宁酸乙酯(22)、3,5-O-二咖啡酰奎宁酸乙酯(23)、4,5-O-二咖啡酰奎宁酸乙酯(24)。其中化合物11014~24 对LPS诱导的RAW264.7细胞中PGE2的分泌具有显著的抑制作用。结论 化合物1~911~1322~24 均为首次从热毒宁注射液中分离得到,有机酸类化合物可能为热毒宁注射液解热抗炎的主要药效物质基础之一。  相似文献   
7.
任洁  周慧  王晨 《中草药》2019,50(4):808-813
目的研究蒺藜科植物蒺藜Tribulus terrester的干燥成熟果实的化学成分。方法利用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、制备HPLC和薄层色谱等方法进行分离、纯化,并结合HR-ESI-MS与现代波谱学技术鉴定化合物结构。结果从蒺藜果实中分离得到14个化合物,分别鉴定为N-p-阿魏酰酪胺(1)、N-trans-p-coumaroyl-3-O-methyldopamine(2)、甲基阿魏酸(3)、咖啡酸甲酯(4)、原儿茶酸甲酯(5)、trifilines A(6)、5β-spirost-25(27)-en-3β-ol-12-one 3-O-{β-D-glucopyranosyl-(1→2)-O-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside}(7)、tribulosaponin B(8)、isoterrestrosin B(9)、25(R)-螺甾烷-3,5-二烯-12-酮(10)、25(R)-螺甾烷-24β-羟基-4-烯-3,12-酮(11)、26-O-β-D-glucopyranosyl-(25S)-5α-furostane-20(22)-en-12-one-3β,26-diol-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-β-D-galactopyranoside(12)、terrestrinone A1(13)和terrestrinone A2(14)。结论化合物1~7为首次从蒺藜科植物中分离得到。  相似文献   
8.
9.
Whether testicular toxicity is mediated by matrix metalloproteinases (MMPs) is an important question that has not been examined. This study investigated the suppressive effect of curcumin and caffeic acid phenethyl ester (CAPE) on oxidative stress, apoptosis, and whether MMPs mediate doxorubicin (DOX)-induced testicular injury. Male rats were randomly divided into eight groups (n = 8 per group). The groups were as follows: sham, dimethyl sulphoxide (100 µL), DOX (3 mg/kg), CAPE (2.68 mg/kg), curcumin (30 mg/kg), DOX+CAPE (3 mg/kg DOX and 2.68 mg/kg CAPE), DOX+curcumin (3 mg/kg DOX and 30 mg/kg curcumin) and DOX+CAPE+curcumin (3 mg/kg DOX, 2.68 mg/kg CAPE and 30 mg/kg curcumin). Injections were administered daily for 21 days. The oxidative stress, MMPs, proinflammatory cytokines and apoptotic markers in the DOX group were higher than the sham group (p < .05); these measures were lower in the groups treated with CAPE and curcumin together with DOX compared with the DOX group (p < .05). The results showed that MMPs mediated DOX-induced testicular injury, but CAPE and especially curcumin suppressed testis injury and cell apoptosis by suppressing DOX-induced increases in MMPs, oxidative stress and proinflammatory cytokines. However, curcumin exhibited more pronounced effects than CAPE in terms of all studied parameters.  相似文献   
10.
PurposeThis study aimed to evaluate bond durability when applying 2 phosphate ester monomer-containing self-adhesive resin cements alone, versus a combination of phosphate ester monomer-containing primer conditioning plus 2 conventional resin cements requiring primers, to zirconia after different artificial aging methods.MethodsWe cemented air-abraded zirconia plates to composite resin cylinders with self-adhesive resin cements (MS; RU) alone or cemented them with traditional resin cements (ZRV; ZVN) after pre-conditioning with a zirconia primer. A shear bond strength (SBS) test were performed after subjecting them to 19 different aging conditions (n = 15) comprising 30,000× thermocycles, air storage at room temperature (RT), water storage at RT, or at 37 °C for 24 h, 1 week, 1, 3, 6, and 12 months. Zirconia powders mixed with zirconia primer or 2 self-adhesive resin cements were characterized by X-ray photoelectron spectroscopy.ResultsGroups MS and ZVN obtained the highest SBS after all of aging methods. SBS after 6 months of storage was similar to SBS after 24 h of storage, while both were higher than SBS after 1 year of storage. Water storage at 37 °C provided higher SBS than RT water storage did. We detected a Zr–O–P bond in both self-adhesive resin cement/zirconia powder mixtures.ConclusionsApplication of self-adhesive resin cements alone could be an alternative to pre-conditioning with a zirconia primer followed by the application of conventional resin cements. Formation of Zr–O–P bonds contributed to the bonding improvement of self-adhesive resin cements. Different aging conditions affected SBS values.  相似文献   
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