HPLC测定注射用尼莫地平的含量及有关物质

目的建立测定注射用尼莫地平含量及有关物质的方法。方法采用HPLC法,用DiamonsilTMC18柱(250 mm×4.6 mm,5μm),流动相为甲醇-水-乙醚(70∶30∶9),检测波长238 nm,柱温为室温;流速1.0 ml.min-1。结果尼莫地平在4.0~40.0μg.ml-1范围内,峰面积和浓度呈良好的线性关系(r=0.9998),最低检测限为0.376 ng,方法精密度RSD=0.35%(n=6),平均回收率为99.8%(n=9)。结论所建方法准确、灵敏、简便、快速,可用于注射用尼莫地平的含量及有关物质的测定。     

HPLC法测定尼莫地平软胶囊的含量及有关物质

目的:建立HPLC法测定尼莫地平软胶囊的有关物质及含量。方法:采用Diamonsil C18色谱柱(250 mm×4.6 mm,5μm),以甲醇-乙腈-水(35∶38∶27)为流动相,流速1.0mL.min-1,柱温为40℃,检测波长为235 nm。结果:尼莫地平和杂质A均在0.1～4.0μg.mL-1浓度范围内与其峰面积呈良好线性关系(r=1.0000),最低检出限均为0.4 ng。高、中、低3种浓度的平均回收率为99.6%,RSD为0.5%(n=9)。结论:该方法简便准确,重复性好,可用于尼莫地平软胶囊的有关物质和含量测定。     

高效液相色谱法测定替米沙坦片含量及有关物质

目的建立一种高效液相色谱法测定替米沙坦片含量及有关物质的方法.方法色谱柱为C18柱,流动相为0.01mol·L-1醋酸铵溶液(用醋酸调节pH6.0)-乙腈(40:60);检测波长有关物质为255nm,含量测定为298nm;流速为1.0mL·min-1.结果替米沙坦在50～250μg·mL-1内,峰面积与浓度呈线性关系,r=0.999 9,平均回收率为100.1%(RSD=0.75%,n=9).结论用HPLC法测定替米沙坦片含量及有关物质方法简便,结果准确.     

HPLC法测定卡培他滨的含量及有关物质

目的建立高效液相色谱法测定卡培他滨含量及有关物质的方法。方法采用C18柱,以B(甲醇∶乙腈∶0.1%醋酸=7∶0.2∶12.8)-C(甲醇∶乙腈∶0.1%醋酸=16∶1∶3)为流动相,梯度洗脱,流速为1.0mL.min-1,进样量为10μL,检测波长为250nm,柱温为40℃,自动进样室为5℃。结果在浓度为0.0997~0.997mg.mL-1范围内线性关系良好(r=0.9999,n=6),检测限为0.020μg.mL-1。该方法能够分离卡培他滨及其有关物质。结论本方法灵敏、准确、专属性及重复性好,可用于卡培他滨的含量测定及有关物质限量检查。     

高效液相色谱法测定泛硫乙胺片剂中泛硫乙胺含量及其有关物质

目的:建立高效液相色谱法测定泛硫乙胺片剂中泛硫乙胺含量及其有关物质的方法.方法:C18色谱柱,流动相为甲醇-水(45:55),流速1.0mL·min-1,UV 210 nm检测,含量和有关物质同时测定.结果:泛硫乙胺在4～500 mg·L-1(n=7)范围内线性关系良好(r=0.999 9);检测限为3.8 ng,方法精密度RSD为1.1%(n=6).3批样品泛硫乙胺的含量为标示量的98.0%～99.5%,有关物质含量为1.0%～1.1%.结论:方法简便、可靠,可用于该品的质量控制.     

RP-HPLC法测定格列齐特片(Ⅱ)含量及其有关物质

建立RP-HPLC法测定格列齐特片(Ⅱ)的含量及有关物质.采用Diamonsil C18柱;以乙腈-水-三乙胺-三氟乙酸(45550.10.1)为流动相;流速为1mL·min-1检测波长为235nm.线性范围1.021～8.165μg,r=0.9994,平均回收率99.36%,RSD=1.48%(n=9).该方法简便、准确、专属,可用于格列齐特(Ⅱ)片含量及其有关物质的测定.     

RP-HPLC法测定醋酸可的松滴眼液主药及有关物质的含量

目的:建立测定醋酸可的松滴眼液主药及有关物质含量的方法。方法:采用反相高效液相色谱法。色谱柱:Agilent C18,流动相:乙腈-水(36∶64),流速:1.1 mL.min-1,检测波长:254 nm,进样量:10μL。结果:醋酸可的松的有关物质检测浓度线性范围为1.0～20.0μg.mL-(1r=1.000 0),相应杂质限度范围为0.1%～2.0%,最低检测限为5 ng(0.05%);主药含量测定的检测浓度线性范围为41.9～168μg.mL-(1r=1.000 0),平均回收率为100.6%(RSD=0.7%)。结论:本方法准确、简便、快速,可满足醋酸可的松主药和有关物质含量测定的要求。     

高效液相色谱法测定烟酰胺凝胶的含量及有关物质

目的建立高效液相色谱法(HPLC)测定烟酰胺凝胶的含量及有关物质.方法采用Hypersil ODS C18色谱柱(4.6 mm×250 mm,5μm)以0.01 mol·L-1磷酸二氢钾溶液(pH 4.5)-乙腈(964,V/V)为流动相,紫外检测波长261nm,流速1.0 mL·min-1,柱温为室温.结果本方法能分离凝胶剂中烟酰胺及其有关物质,烟酰胺在0.08～0.28μg范围内呈良好的线性关系,r=0.999 6(n=6).平均回收率为100.2%,RSD为0.9%(n=9).结论本方法专属性好、准确、稳定可靠,可用于烟酰胺凝胶的含量测定及有关物质检查.     

HPLC测定青蒿素原料药的含量并检查有关物质

目的 建立直接测定青蒿素原料药的含量和检查有关物质的方法.方法 采用HPLC法,色谱柱为Agilent C18柱,流动相为乙腈-水(65:35),流速1 ml·min-1,检测波长205 nm.结果 青蒿素进样量6.0～50.0μg与峰面积的线性关系良好(r=0.9999,n=6),平均回收率为100.1%,RSD=1.3%.结论 所用方法可用于青蒿素含量的测定及有关物质的检查.     

HPLC法测定尼群地平片的含量及有关物质

目的:建立一种高效液相色谱法测定尼群地平片的含量及有关物质的方法.方法:以C18为固定相,甲醇-水(70 : 30)为流动相,检测波长:237nm.结果:尼群地平片的浓度在20～180μg/ml范围内线性关系良好,回归方程:Y=39128X-66845,r=0.9999精密度试验RSD%=0.9%(n=9),片剂的回收率为100.5%(RSD%=0.6%,n=5).有关物质可检出2个杂质.结论:本方法测定尼群地平的含量及有关物质,分离效果好,结果准确.     

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.