HPLC法同时测定银杏叶提取物两种不同剂型中黄酮类化学成分的含量

目的测定银杏叶片提取物两种不同剂型中槲皮素、山奈酚、异鼠李素3种黄酮类化学成分的含量。方法采用HPLC法测定槲皮素、山奈酚、异鼠李素的含量。结果槲皮素、山奈酚和异鼠李素分别在6.4～32.0μg/mL、4.4～22.0μg/mL、3.2～16.0μg/mL内峰面积与浓度呈良好的线性关系。精密度RSD小于1.29%,良好;回收率为98.9%～100.4%。结论本实验建立了可同时测定槲皮素、山奈酚和异鼠李素3种成分的HPLC方法。该方法简便、准确,可用于银杏叶提取物片剂和注射剂的质量控制。     

银杏叶提取物注射液中槲皮素、山柰酚、异鼠李素及总黄酮醇苷的HPLC法测定

建立了高效液相色谱法测定银杏叶提取物注射液中的槲皮素、山柰酚、异鼠李素及总黄酮醇苷,评价了注射液的质量.色谱柱为Diamonsil C18柱,流动相为甲醇-0.4％磷酸(55∶45),检测波长360 nm.银杏叶提取物注射液水解前后,其主要组分槲皮素、山柰酚和异鼠李素分离良好,线性范围宽,平均加样回收率水解前分别为100.2％、100.3％和100.2％,RSD分别为0.64％、1.14％和0.40％水解后分别为100.0％、100.7％和100.3％,RSD分别为0.79％、0.98％和1.00％.     

槲皮素代谢产物定性检出条件研究

目的:研究给予大鼠槲皮素后血浆中代谢产物的定性检出条件。方法:给予大鼠槲皮素单体(100mg.kg-1)后腹腔静脉取血,血浆样品经2mol.L-1盐酸(甲醇-水溶液)水解,采用高效液相色谱法对血浆样品中代谢产物进行定性分析。结果:大鼠给药后3h内取血、血浆样品经盐酸水解处理4h,可稳定检测槲皮素和异鼠李素,样品在—20℃条件下贮存稳定。结论:血浆样品采集时间、盐酸水解时间及贮存方式等不同均可影响代谢产物的有效检出。     

HPLC-MS/MS法同时测定Beagle犬血浆中槲皮素、山萘酚和异鼠李素(英文)

目的:建立同时测定犬血浆中槲皮素、山萘酚和异鼠李素浓度的HPLC-MS/MS方法。方法:血浆样品经酸水解后用乙醚提取,采用选择性反应检测方法测定其血药浓度。仪器为Finni-ganLC-MS/MS二级四极杆质谱检测器,色谱柱为LunaC18(150mm×2.00mmi.d.,5μm,Luna,USA);流动相为乙腈-0.1%甲酸,梯度洗脱。结果:槲皮素、山萘酚和异鼠李素的线性范围均为0.5～100.0ng/mL,三种黄酮的最低定量限均为0.5ng/mL,各自日内日间精密度分别小于7.3%,6.2%和6.4%,回收率分别大于70%,66%和70%。结论:该测定方法经验证符合血浆样品的测定要求,可以应用于临床前药代动力学研究。     

银杏叶提取物与不同比例刺梨配伍后对银杏黄酮含量的影响

目的 观察不同比例刺梨与银杏叶提取物(GbE)配伍对银杏黄酮含量的影响.方法 采用反相高效液相法测定槲皮素、山萘素、异鼠李素含量.结果 测定方法精密度RSD≤2.31%,平均加样回收率分别为100.77%、101.79%、99.73%,RSD≤4.35%.银杏叶提取物与刺梨以1∶0、1∶0.5、1∶1、1∶2配伍后银杏黄酮含量分别为25.01%、25.13%、24.96%、24.45%.结论 一定量刺梨与GbE配伍对银杏黄酮含量无明显影响.     

高效液相色谱法测定银杏叶片剂中银杏黄酮含量

目的建立高效液相色谱法测定银杏叶制剂天保宁片剂中银杏黄酮的含量。方法色谱柱为YWGC18-ODS柱(250mm×4.6mm),流动相由磷酸缓冲液(pH2)-四氢呋喃-甲醇-异丙醇(60:15:10:15)组成,流速0.5mL·min-1,紫外检测波长380nm。结果槲皮素和山柰酚在2.5-50mg·L-1,异鼠李素在1.362-27.38mg·L-1的浓度范围内线性关系良好,回归方程为槲皮素:y=145642x-314528,r=0.9994;山柰酚:y=94650x-197111,r=0.9993;异鼠李素:y-62031x-20056,r=0.9997;槲皮素、山柰酚、异鼠李素平均回收率分别为99.06%,99.89%,99.06%,RSD分别为1.33%,2.21%,1.85%。检测限槲皮素和山柰酚均为0.125mg·L-1,异鼠李素0.068mg·L-1。结论本法简便,快速,灵敏,准确,重现性好,可作为控制银杏黄酮制荆质量标准的依据。     

高效液相色谱法测定复方银茶方银杏黄酮苷含量

目的用高效液相色谱 紫外检测器法（HPLC UV）测定复方银茶方中银杏黄酮苷的含量。方法复方银茶样品经酸水解回流提取,采用Diamonsil C18 （4.6 mm×250 mm,5 μm）色谱柱,以甲醇 0.4%磷酸溶液（52：48）为流动相,以紫外检测器在370 nm波长下检测。结果复方银茶样品经酸水解得到槲皮素、山奈酚、异鼠李素3种苷元,槲皮素、山奈酚、异鼠李素分别在8.34～83.40 μg•mL 1,5.91～59.10 μg•mL 1,2.425～24.250 μg•mL 1范围内线性关系良好;槲皮素、山奈酚和异鼠李素的平均回收率分别为93.16%,94.25%,95.85%。结论该方法简便、准确、分离效能高,可用于复方银茶方中黄酮苷成分的含量测定。     

银杏叶片中总黄酮醇苷的含量测定

目的建立反相高效液相色谱法测定银杏叶片样品中总黄酮醇苷(槲皮素、山柰素、异鼠李素)的含量测定方法。方法采用phenomenex C18色谱柱,流动相为甲醇-0.4%磷酸水溶液(5050),流速为1.0ml/min,检测波长为360nm,柱温:25℃。结果总黄酮醇苷中槲皮素在与山柰素在0.0075~0.06mg/ml(r=0.9999,n=5)、异鼠李素在0.005~0.04mg/ml(r=0.9995,n=5)浓度范围内具有较好的线性关系;平均加样回收率槲皮素为99.92%(RSD=1.65%,n=6),山柰素为98.60%(RSD=1.3%,n=6),异鼠李素为99.41%(RSD=0.81%,n=6)。结论该法操作简便、灵敏度高、重现性好,可用于银杏叶片中总黄酮醇苷的含量测定。     

LC-MS鉴定大鼠血浆山柰酚代谢产物

目的:采用液相色谱-质谱联用技术鉴定大鼠给药山柰酚单体后血浆中代谢产物。方法:取给药后大鼠的血浆样品经酶水解、酸水解后,进行色谱分离,采用液相色谱-质谱联用仪检测,大气压电喷雾离子源(EPI)负离子条件下进行扫描,鉴定大鼠给药山柰酚(30 mg.kg-1)单体后血浆中代谢产物的结构。结果:通过与山柰酚对照品谱图比较,结合质谱仪扫描结果分析,在大鼠给药山柰酚单体后血浆中鉴定出山柰酚(m/z286.0)代谢产物结构。结论:采用酶水解、酸水解的方法可快速、有效地鉴定出大鼠血浆中山柰酚代谢产物,为进行含山柰酚中药及其复方的药物代谢动力学研究奠定科学基础。     

银杏叶提取物咀嚼片的制备及质量标准研究

<正>银杏叶提取物(EGb)是从银杏叶中提取的具有独特药理活性的混合物,药理研究结果显示,EGb中含有黄酮类、萜类内酯、聚异戊烯醇类、有机酸、烷基酚和烷基酚酸、甾体化合物、氨基酸和微量元素在内的100多种化学成分。银杏叶中的黄酮含量较高,为2.5%～5.91%,所含黄酮种类超过35种之多,其中黄酮苷17种、双黄酮6种、黄酮苷元7种和桂皮酰衍生物5种。代表银杏叶药效的主要是黄酮苷,苷元主要有山奈酚、槲皮素、异鼠李素。银杏叶提取物能改善心脑血液循环,扩张心脑血管,改善血液流变学,清除自由基,对心血管     

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.     

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.     

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.     

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.     

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.