HPLC分析大蒜多糖中的单糖

目的 建立一种反相高效液相色谱法(RP-HPLC)分析大蒜多糖中的单糖组成及摩尔比。方法 大蒜多糖样品经2 mol·L^-1硫酸降解为单糖后,经1-苯基-3-甲基-5-吡唑啉酮( PMP)衍生化,采用Shimadzu VP-ODS柱(150 mm×4.6 mm,5 μm)分离,以乙腈-醋酸铵缓冲溶液(取醋酸铵7.708 g加水溶解并稀释至1 000 mL,用醋酸调pH 5.5 (22∶78)为流动相,流速为0.8 mL·min^-1,在245 nm处检测单糖的衍生化产物。结果 大蒜多糖中甘露糖(Man)、鼠李糖(Rha)、葡萄糖醛酸(GlcUA)半乳糖醛酸(GalUA)、葡萄糖(Glc)、半乳糖(Gal)、阿拉伯糖(Arab)7种单糖的摩尔比为4.31∶4.23∶4.19∶9.13∶27.4∶4.99∶3.81。结论 本方法灵敏度高,结果准确可靠,可用于大蒜多糖的单糖组成测定及质量控制。     

柱前衍生化HPLC分析蒲公英多糖的单糖组成

目的 合理优化衍生方法测定蒲公英多糖中单糖的组成及摩尔比。方法 采用1-苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生,用反相高效液相色谱法进行测定。色谱条件为：ZORBAX-C₁₈柱;流动相：0.1 mol·L^-1的磷酸盐缓冲液(pH 6.7)-乙腈(83∶17);流速：1 mL·min^-1;检测波长：245 nm;进样量：20 μL;柱温：室温。结果 蒲公英多糖由D-鼠李糖、葡萄糖、D-半乳糖、D-木糖和D-阿拉伯糖组成,以不同方法提取的各单糖含量的摩尔比为：水提取法,Rha∶Glc∶Gal∶ Ara=0.088∶0.500∶0.190∶0.340;超声提取法,Rha∶Glc∶Gal∶Ara=0.050∶0.350∶0.080∶0.320;酶提取法,Rha∶Glc∶ Gal∶Ara=0.270∶0.630∶0.330∶0.460;超声协提取同酶法,Rha∶Glc∶Gal∶Ara =0.078∶0.550∶0.130∶0.170。结论 改进后的衍生化方法和等度洗脱的色谱方法具有操作简单、快速、重复性好等特点,可用于蒲公英多糖中单糖组成和摩尔比的测定。     

高效毛细管区带电泳法分析南瓜多糖的单糖组成

目的测定南瓜多糖的单糖组成及摩尔比。方法以1-苯基-3-甲基-5-吡唑啉酮(PMP)为单糖的柱前衍生化试剂,用毛细管区带电泳(CZE)法测定南瓜多糖的单糖组成。电泳缓冲液为pH10.8的150mmol·L-1硼砂水溶液;熔融石英毛细管柱(58.5cm×75μm)的有效长度为48.5cm;分离电压10kV;柱温25℃;3.45kPa压力进样,进样时间5s;二极管阵列检测器检测。结果各单糖的检测限均低于10μg·mL-1。南瓜多糖由木糖、阿拉伯糖、葡萄糖、鼠李糖、半乳糖、葡萄糖醛酸组成,其摩尔比为1.33∶3.12∶7.33∶1.0∶3.67∶6.06。结论该方法具有简单、快速、高效等优点,可用于南瓜多糖的单糖组成测定及质量控制。     

柱前衍生化HPLC法测定不同基源金线莲多糖的单糖组成

目的:建立测定不同基源金线莲多糖中单糖组成的方法。方法:采用高效液相色谱法。色谱柱为Alltima-C18,柱温为30℃,流动相为0.1 mmol/L磷酸盐缓冲溶液(Na H2PO4-Na2HPO4,p H=6.7)-乙腈(83∶17,V/V),流速为1.0 ml/min,检测波长为254nm。结果:花叶开唇兰多糖由甘露糖、半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖组成,其物质的量之比为2.52∶0.53∶1.00∶5.07∶1.58;台湾银线兰多糖由甘露糖、半乳糖醛酸、葡萄糖和半乳糖组成,其物质的量之比为1.10∶0.50∶1.00∶1.92;滇越金线兰多糖由甘露糖、葡糖醛酸、半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖组成,其物质的量之比为2.95∶0.28∶0.53∶1.00∶9.30∶2.26。甘露糖、葡糖醛酸、半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖的进样量分别在0.32~3.18μg(r=0.999 9)、0.08~0.83μg(r=0.9999)、0.08~0.78μg(r=0.999 9)、0.13~1.32μg(r=0.999 9)、0.38~3.75μg(r=0.999 8)、0.24~2.43μg(r=0.999 7)范围内与各自峰面积呈良好线性关系;精密度、重复性、稳定性试验的RSD<3%;平均加样回收率分别为99.34%、98.43%、99.79%、98.93%、99.50%、99.71%(n=6)。结论:该方法简单、快速、分离效率高,可用于测定不同基源金线莲多糖中的单糖组成。     

天冬多糖的提取与单糖组成分析

目的 从常用中药天冬中提取多糖,并建立柱前衍生化高效液相色谱法分析天冬多糖的单糖组成. 方法采用水提醇沉法提取天冬多糖. 用2 mol&#8226;L^-1 硫酸溶液将多糖水解成单糖,用1-苯基-3-甲基-5-吡唑啉酮(PMP)与水解后的单糖进行衍生化反应;衍生产物采用反相高效液相色谱法分离,并在250 nm波长处检测,研究天冬多糖的单糖组成. 结果 水提醇沉法提取的多糖经过精制后,所得多糖的平均含量可达95.84%. 用高效液相色谱法检测天冬多糖中单糖组成比例为甘露糖:鼠李糖:葡萄糖醛酸:葡萄糖:半乳糖:阿拉伯糖(2.18:0.95:1.00:1.62:2.06). 结论 该多糖提取及精制方法可得到含量较高的天冬多糖. 柱前衍生的高效液相色谱法可用于天冬多糖的单糖组分分析,该法操作简便,结果 准确,适用于多糖中的单糖组成分析.     

LC-ESI-MS/MS快速测定人血浆中匹伐他汀浓度

目的 建立一种快速灵敏测定人体血浆中匹伐他汀浓度的高效液相色谱串联质谱检测方法。方法 以Agilent C18柱(4.6 mm×150 mm,3.5 μm)为色谱柱,流动相为甲醇-0.005 mol·L^-1甲酸铵水溶液-乙腈-1%甲酸水溶液(7.5∶2.5∶70∶20);流速：0.5 mL·min^-1,柱温：40 ℃。采用选择反应监测(SRM)对匹伐他汀(m/z 422.2→290.2)和内标瑞舒伐他汀(m/z 482.2→258.2)进行测定。结果 匹伐他汀高(80 μg·L^-1)、中(50 μg·L^-1)、低(0.25 μg·L^-1)3个浓度的平均回收率RSD均小于15%;线性范围为：0.1~100 μg·L^-1,回归方程为Y=1.222 6X-1.056 1×10^-4,r=0.996 0。结论 该方法灵敏、准确、简单、快速,可用于匹伐他汀临床血药浓度监测和药动学研究。     

动力学分光光度法测定中药多糖对羟自由基的清除率

目的 根据羟自由基与水杨酸(SA)氧化反应的动力学过程,建立动力学分光光度法测定中药多糖对羟自由基(·OH)的清除率。方法 应用紫外分光光度法,建立·OH与SA反应的动力学曲线,根据动力学曲线斜率的变化测定中药陈皮和灵芝多糖对·OH的清除率,并用维生素C进行方法的重复性与可靠性验证。结果 测定陈皮多糖对·OH 的50%清除率(IC50)为232.6 mg·L^-1;灵芝IC50为0.856 1 g·L^-1;维生素C的 IC50为0.254 4 mmol·L^-1,RSD为0.2％(n＝5)。结论 此方法灵敏可靠,可用于中药多糖成分对·OH清除率的测定。     

HPCE测定夏枯草中迷迭香酸含量

目的 建立高效毛细管电泳法测定夏枯草中迷迭香酸的含量。方法 采用毛细管区带电泳法。电泳条件为：石英毛细管柱(75 μm×60 cm);运行缓冲液：20 mmol·L^-1的硼砂溶液(pH 9.88);分离电压18 kV;进样时间为5 s;温度为25℃,检测波长为 330 nm。结果 迷迭香酸在20.4~163.2 μg·mL^-1内线性关系良好(r=0.999 4);平均回收率为97.7%,RSD为1.6%。结论 该方法简便、快速、准确并且专属性强,可用于测定夏枯草中迷迭香酸的含量。     

反相高效液相色谱法测定曲普利啶的血浆浓度和药动学

目的 建立高效液相色谱法测定曲普利啶人血浆浓度的方法。方法采用反相高效液相色谱法，色谱柱采用Nova-pak-C18(300 mm×3.9 mm，4 μm)，流动相为乙腈∶0.075 mol·L^-1磷酸盐缓冲液(含0.16%二乙胺，pH值2.6)(25∶75，V/V)。血浆样品用乙醚提取。结果曲普利啶的线性范围为1.09～109.20 μg·L^-1，最低检测浓度为1.09 μg·L^-1。高、中、低3种浓度(54.60，10.90，2.73 μg·L^-1)的日内、日间变异均＜10%。结论该方法灵敏、稳定、精确，适用于曲普利啶生物样本的测定和药动学研究。     

豚鼠心内注射给药后外耳淋巴液和血浆地塞米松磷酸钠的浓度测定

目的建立测定豚鼠外耳淋巴液和血浆中地塞米松磷酸钠含量的方法。方法采用高效液相色谱法测定淋巴液和血浆地塞米松磷酸钠的浓度。固定相：ZORBAX Eclipse XDB-C18色谱柱(4.6 mm×250 mm， 5 μm)；流动相：7.56 mmol·L^-1硫酸铵 乙腈(70∶30)；流速：1.0 mL·min^-1；柱温：20℃；检测波长：239 nm。结果地塞米松磷酸钠浓度测定的线性范围为0.05～4.80 mg·L^-1，r＝0.999 8，最低检测限为6.25 μg·L^-1，日内和日间RSD分别为1.7%和2.3%。给药后1 h鼓阶外淋巴液中地塞米松磷酸钠的浓度为0.08 mg·L^-1，血浆中地塞米松磷酸钠浓度为2.77 mg·L^-1。结论该方法灵敏、准确、重现性好，可用于血浆和外耳淋巴液中地塞米松磷酸钠的浓度测定。全身给药治疗内耳疾病不是适宜的给药方式，应该探索其他给药途径。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

---

Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.