毛细管电泳法测定(S)-2-(6-羟基-2,3-二氢苯并呋喃-3-基)乙酸甲酯中R异构体

目的建立毛细管电泳法测定(S)-2-(6-羟基-2,3-二氢苯并呋喃-3-基)乙酸甲酯中R异构体的方法。方法采用毛细管电泳法。以磺酸-β-环糊精(S-β-CD)为选择剂;25 mmol/L硼酸盐缓冲液(pH 8.9,含S-β-CD 1.8%)为运行缓冲液;运行电压为25 kV;柱温为15℃;检测波长:214 nm;3.4 kPa压力进样10 s。结果 (S)-2-(6-羟基-2,3-二氢苯并呋喃-3-基)乙酸甲酯与R异构体的分离度为2.9。R异构体在2~30μg/m L与峰面积线性关系良好(r=0.999 5),平均回收率为96.6%,RSD值为4.9%(n=6)。结论建立的毛细管电泳法操作简便,结果准确可靠,可用于(S)-2-(6-羟基-2,3-二氢苯并呋喃-3-基)乙酸甲酯中R异构体的控制。     

胶束动电毛细管色谱选择性分析植物提取物中的托品烷生物碱

用含50mmol/L SDS、30mmol/L 硼酸盐-磷酸盐缓冲液(pH8.5),以胶束动电毛细管色谱方法同时分析6个托品烷生物碱,包括天仙子胺(hyoscyamine)和莨菪胺。对分离条件的优化进行了研究和讨论。加入有机改性剂可改善分离效率和分离度。而且只有加入有机溶剂(甲醇或乙腈)才能分离两个空间异构体天仙子胺和 littorine。毛细管电泳系统以二极管阵列检测器     

毛细管电泳手性拆分西他沙星异构体

目的:建立西他沙星及其异构体高效毛细管电泳拆分的新方法。方法:以β-环糊精及几种环糊精衍生物作为手性添加剂,采用毛细管电泳分离新型抗菌素西他沙星与其3个异构体。对运行缓冲液的浓度、pH,环糊精的种类、二元环糊精体系中环糊精的比例,分离电压,柱温,有机改性剂等因素对分离的影响进行考察,并对拆分机制进行初步探讨。结果:运行缓冲液为含2%硫酸化-β-环糊精和1%β-环糊精的25 mmol.L-1的磷酸二氢钾-磷酸缓冲溶液(pH 2.5),操作电压为-25kV,柱温为25℃,检测波长为295 nm,西他沙星与其3个异构体达到良好分离。结论:所建立的毛细管电泳方法简便,适用于西他沙星异构体的检查。     

山莨菪碱对A_(23187)诱导的血小板内游离钙升高的影响

应用Quin-2测得含有1mmol/L CaCl_2和2mmol/L EGTA的介质中血小板内静息游离钙浓度为52.1±5.2nmol/L和28.4±5.1nmol/L。A_(23187)诱导的血小板在有钙或无钙时胞浆游离钙增加的峰值分别为145.8±30.8nmol/L和34.4±2.4nmol/L,山莨菪碱对静息游离钙和无外源钙时A_(23187)刺激的游离钙无影响,山莨菪碱(100μmol/L,25μmol/L)、维拉帕米(10μmol/L)分别降低有外源钙时A_(23187)诱导的游离钙峰值38%、34%、25%。山莨菪碱具有钙拮抗作用。     

胶束电动毛细管色谱法分析头孢吡肟与其E异构体等杂质

目的 以十二烷基硫酸钠(SDS)胶束为准固定相,考察头孢吡肟、头孢吡肟E异构体及其他未知杂质在胶束电动毛细管色谱(MECC)分离模式下的分离行为.方法 研究了运行缓冲液的pH值、磷酸盐浓度、SDS浓度、甲醇体积分数、分离电压、分离温度等因素对头孢吡肟、E异构体及其他杂质的迁移时间、分离度以及可分离出的杂质个数的影响.结果 发现上述因素对头孢吡肟与诸杂质间的分离及检测有显著的影响,尤以pH值为最.它不仅影响它们的迁移时间和分离效率,还直接影响头孢吡肟及其杂质峰的检测.优化后的分离条件:运行缓冲液为70mmol/L磷酸盐/100mmol/L SDS-5%甲醇(pH7.0),分离电压为15kV,分离温度为25℃.用非涂渍石英毛细管51cm×75μm(有效长度42.5cm),压力进样5s,检测波长254nm.结论 本法可分离出34个杂质,诸杂质彼此间及与头孢吡肟间可得到有效分离,可用于测定盐酸头孢吡肟的含量和有关物质.     

毛细管电泳快速测定银黄口服液中黄芩苷和绿原酸含量

目的 建立毛细管电泳法测定银黄口服液中绿原酸、黄芩苷的方法.方法 用毛细管电泳法测定银黄口服液中绿原酸、黄芩苷的含量.以弹性石英毛细管柱为分离柱,25mmol/L硼砂缓冲溶液为运行缓冲液,分离电压为15 kV,检测波长为325 nm.结果 在优化的条件下,15 min内实现了绿原酸和黄芩苷的良好分离,绿原酸、黄芩苷峰面积和浓度分别在0.05～1.0g/L和0.1～2.0g/L呈良好线性;检出限分别为绿原酸0.01g/L,黄芩苷0.02g/L,回收率为98%～102%.结论 毛细管电泳法适合银黄口服液的质量控制.     

间尼索地平的胶束电动毛细管电泳法测定

建立了胶束电动毛细管电泳法测定间尼索地平.采用未涂层融硅石英毛细管,10 mmol/L磷酸二氢钠-5 mmol/L硼砂缓冲液(含30 mmol/L SDS,pH 8.1)为运行缓冲液,分离电压30 kV,检测波长214nm.间尼索地平浓度在30～120μg/ml范围内线性关系良好,检测限为0.9μg/ml.     

育亨宾的非水毛细管电泳法测定

建立了非水毛细管电泳法测定育亨宾的含量。以盐酸小檗碱为内标,采用熔融石英毛细管,缓冲液为20mmol/L乙酸铵的甲醇液(含0.5%冰醋酸),检测波长220nm,运行电压25kV,柱温25℃,压力进样50mbar×5s。育亨宾在1～40μg/ml浓度范围内线性关系良好(r=0.9996),回收率为97.2%,RSD为1.8%。     

尼群地平和尼莫地平的光学异构体的高效毛细管电泳法分离

建立了高效毛细管电泳法拆分并测定尼群地平片和尼莫地平片中的光学异构体.采用未涂层弹性融硅石英毛细管柱,以40 mmol/L磷酸二氢钠溶液(以磷酸调至pH 2.96)-10 mmol/L磺丁基醚-β-环糊精为运行缓冲液,分离电压-15 kV,检测波长237 nm.尼群地平和尼莫地平对映体得到基线分离,分离度为3.43和2.08.考察了环糊精的浓度、缓冲液浓度和pH、分离电压等的影响,并运用计算机分子模拟技术对环糊精与对映体间的拆分机制进行探讨.     

高效毛细管电脉法分离测定感冒通中双氯灭痛和扑尔敏的含量

目的:测定感冒通中双氯灭痛和扑尔敏的含量。方法:采用高效毛细管电泳法进行分离测定。用内含25mmol/L脱氧胆酸钠的20mmol/L H_3BO_3-NaOH(PH 10)为缓冲液,以咖啡因为内标,进行定量测定。结果:可在7分钟内将上述两种组分完全分离且其迁移时间具有良好的重现性。结论:高效毛细管电泳法是一种较为理想的方法学手段。     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

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.

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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.     

Synthesis,Cytotoxicity and Antileishmanial Activity of Some N-(2-(indol-3-yl)ethyl)-7-chloroquinolin-4-amines

We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells.     

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.     

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.