帕珠沙星对映体的手性流动相添加剂HPLC法拆分

建立了拆分帕珠沙星对映异构体的HPLC手性流动相法.使用ODS柱,流动相为乙腈-L-苯丙氨酸手性溶液(5:95),检测波长320nm.左旋体和右旋体色谱峰的保留时间分别为30.2和33.8min.     

甲磺酸帕珠沙星对映异构体的拆分方法及其应用

目的:建立一种用手性流动相拆分并测定甲磺酸帕珠沙星对映异构体的方法。方法:使用HYPERSIL BDS C18柱(4.6mm×250 mm,5μm),流动相为含有3 mmol·L-1硫酸铜、6 mmol·L-1 D-苯丙氨酸的溶液-甲醇(78:22),流速为1 mL·min-1,在250nm检测。结果:R-(+)和S-(-)甲磺酸帕珠沙星的保留时间分别为8.1和9.7 min,分离度为2.2。结论:方法的重现性好,操作简单,可用于药品质量控制。     

RP-HPLC法检测甲磺酸帕珠沙星注射剂中右旋体含量

目的 :建立RP HPLC法检测甲磺酸帕珠沙星注射剂中右旋体含量。方法 :采用岛津C1 8柱 (4 6mm× 2 5 0mm ,5 μm) ,流动相为甲醇 手性溶液 (30∶70 ) ,流速为 1 0mL min ,紫外检测波长为 32 0nm。 结果 :甲磺酸帕珠沙星右旋体的保留时间为 6 8min ,其浓度在 12 5 2～ 37 5 4 μg mL范围内 ,呈良好的线性关系 (r =0 9995 ,n =5 ) ,平均回收率为 99 16 % ,RSD为 0 33% (n =5 )。结论 :本法简便快速 ,精密度良好 ,可作为甲磺酸帕珠沙星制剂的质量控制方法。     

RP-HPLC手性流动相添加剂法拆分甲磺酸帕珠沙星对映体的研究

目的建立新药甲磺酸帕珠沙星(PZLX)对映体手性流动相HPLC拆分方法。方法通过探讨流动相pH值、有机改性剂、手性配合剂、反相固定相对手性拆分的影响,确定甲醇-苯丙氨酸溶液(L-苯丙氨酸1.32g与硫酸铜1g,加水1000ml,氢氧化钠试液调节pH值为3.5)(30∶70)为手性流动相,在ODS柱上拆分PZLX对映体,332nm波长检测。结果两对映体良好分离,分离度1.9以上,S、R异构体回归方程分别为:Y=1.38×105X-130.9(r=0.9998)和Y=1.26×105X-60.6(r=0.9998),最低检出限分别为1.2和1.5ng,RSD为0.2%以下。结论所建立的方法简便易行,克服了该类方法灵敏度及重现性不如手性固定相法(CSP)的不足,可用于新药PZLX光学纯度的质量控制及其生物体内代谢立体选择性的研究。     

高效液相色谱法测定甲磺酸帕珠沙星注射液中右旋体的含量

目的建立甲磺酸帕珠沙星注射液中右旋异构体含量的高效液相色谱测定方法。方法Shim pakCLC ODS柱 (15 0mm× 6 .0mm ,5 μm) ,流动相为L 异白氨酸硫酸铜溶液 (取L 异白氨酸 1.3g、硫酸铜 1.0g和水 10 0 0ml溶解用 0 .1mol/L盐酸或 0 .1mol/L氢氧化钠调pH至 3.5 ) 甲醇 (75∶2 5 ) ;检测波长 :32 0nm。结果甲磺酸帕珠沙星右旋体在 0 .5～ 10 0 μg/ml浓度范围内呈良好的线性关系 (r=0 .9993) ,平均回收率为 99.5 4 % ,RSD为 1.0 1% (n =9)。结论此法快捷、专属性及重现性好 ,可用于甲磺酸帕珠沙星和D 甲磺酸帕珠沙星杂质的含量测定。     

高效液相色谱法测定人血清中帕珠沙星的浓度

目的:建立测定人血清帕珠沙星的高效液相色谱的方法,并测定了人血清中帕珠沙星的浓度。方法:色谱条件:LunaC18,粒径5 μm,4.6 mm×150 mm;流动相:乙腈-0.04 mol·L-1磷酸盐缓冲液(1:3,pH=3.1),流速1.0 mL·min～1;柱温28℃;检测波长:242 nm,自动进样器温度为室温,进样量20μL,运行时间为10 min。样品处理采用蛋白沉淀法。结果:线性范围:0.05—40μg·mL～1,最低检测浓度为0.05μg·mL～1,绝对回收率均在95％以上,相对回收率在95％-106％,日内、日间的RSD皆小于15％。结论:适用于临床上测定血清中帕珠沙星的人体药动学的研究。     

高效液相色谱法同时测定帕珠沙星和氨茶碱的含量

目的:建立同时测定帕珠沙星和氨茶碱含量的HPLC方法,并考察两种药物配伍后的稳定性。方法:分析柱为shimpackC18柱(150mm×4.6mm);流动相为磷酸二氢钾缓冲液-甲醇(17∶10),用磷酸调pH至3.7;检测波长为239nm。结果:帕珠沙星线性范围为0.5~5.0mg.L-1(r=0.9997)。相对回收率为101.4%;茶碱线性范围为1.0~20.0mg.L-1(r=0.9998)。相对回收率为100.2%。结论:以HPLC法用甲醇做溶剂可同时测定帕珠沙星与氨茶碱的含量。该方法简便、准确、灵敏。     

HPLC法测定甲磺酸帕珠沙星原料及其制剂含量

目的:采用高效液相色谱法测定甲磺酸帕珠沙星原料及其制剂含量.方法:Hypersil C18(5 μm,4.6 mm×250 mm)色谱柱,0.1%磷酸溶液(加磷酸氢二钾80.5 mg)-乙腈(85:15)为流动相,流速1.0ml·min-1,柱温30℃,检测波长243 nm.结果:甲磺酸帕珠沙星在5～500μg·ml-1内与峰面积呈良好的线性关系.甲磺酸帕珠沙星原料(3批)加样回收率99.2%甲磺酸帕珠沙星注射液加样回收率均值为100.1%;甲磺酸帕珠沙星氯化钠注射液加样回收率均值为99.7%.结论:采用HPLC测定原料及其制剂中甲磺酸帕珠沙星含量方法简便,结果可靠.     

RP-HPLC法测定甲磺酸帕珠沙星及有关物质

目的建立甲磺酸帕珠沙星的RP-HPLC含量测定及有关物质检测方法.方法采用C18柱(5μm,4.6mm×250mm),流动相为乙腈-磷酸三乙胺水溶液(含0.5%磷酸,1%三乙胺)(5248),检测波长为254nm.结果甲磺酸帕珠沙星在1.0～200μg@mL-1浓度范围内,峰面积与浓度呈良好线性关系(r=0.9997),平均回收率为(99.3±0.56)%.结论本法简便,专属性及重现性好,可用于测定甲磺酸帕珠沙星含量及有关物质.     

帕珠沙星消旋体的合成及HPLC法拆分

以3-甲基-9,10-二氟-7-氧代-2,3-二氢-7H-吡啶并[1,2,3-de][1,4]苯并噁嗪-6-羧酸乙酯(3)为原料,经亲核取代、脱羧、环合、水解、Hofmann降解可制得帕珠沙星消旋体(1),总收率25.1%.并建立了HPLC法分离1的光学异构体.采用Zorbax C18柱,甲醇-手性溶液(8mmol/L L-苯丙氨酸和4mmol/L硫酸铜混合溶液,用NaOH溶液调至pH3.5)(15:85)为流动相,检测波长为324nm,光学异构体可被良好分离,检测限2ng.     

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.     

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.     

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.