HPLC法测定复方氯霉素醇溶液中氯霉素和水杨酸的含量

目的建立高效液相色谱法同时测定复方氯霉素醇溶液中氯霉素和水杨酸的含量。方法色谱柱：Eclips XDB-C18（4.6 mm×250 mm,5μm）;流动相：1%冰醋酸-甲醇（60∶40）;流速：1.0 mL/min,进样量10μL;检测波长为293 nm。结果氯霉素、水杨酸线性范围均为6-160μg/mL（r=1）;平均回收率分别为99.45%（RSD=0.46%,n=6）,100.32%（RSD=0.97%,n=6）。结论该方法简便、准确、可靠,可同时测定复方氯霉素醇溶液中氯霉素、水杨酸的含量。     

高效液相色谱法测定氯霉素醇溶液含量

目的采用高效液相色谱法测定氯霉素醇溶液含量。方法色谱柱：Kromasil C18(4.6 mm×250 mm,5 μm);流动相：0.1%庚烷磺酸钠溶液 乙腈(75：25);流速：1 mL•min 1;检测波长：272 nm。结果氯霉素醇溶液在14.07～70.36 μg•mL 1范围内与峰面积呈良好的线性关系,回归方程为：A=－8.4×10 4+0.490 6C,r=0.999 98(n=5),回收率=99.20%。结论该方法可有效控制氯霉素醇溶液质量。     

高效液相色谱法测定复方氯霉素醇溶液中水杨酸与氯霉素含量

［摘要］目的建立同时测定复方氯霉素醇溶液中水杨酸和氯霉素含量的高效液相色谱法。方法选用ZORBAX Eclips XDB C18（4.6 mm×150 mm,5 μm） 色谱柱;流动相：甲醇 水（50：50）,流速0.6 mL•min 1;双波长双通道检测：水杨酸的检测波长为300 nm,氯霉素的检测波长为278 nm;用外标法计算含量。结果水杨酸和氯霉素均在0.01～0.10 mg• mL 1范围内线性关系良好（r=0.999 9）,平均回收率均为100.0%。结论该方法操作简便、结果准确,能同时测定复方氯霉素醇溶液中水杨酸和氯霉素含量,可用于该制剂的含量测定和质量控制。     

高效液相色谱法测定氯霉素甲硝唑搽剂的含量

目的建立高效液相色谱法同时测定氯霉素甲硝唑搽剂中两组分含量。方法采用高效液相色谱法测定氯霉素和甲硝唑的含量。色谱条件为:Agilent Extend-C18色谱柱(4.6×250mm),流动相:甲醇-水-冰醋酸(45∶55∶0.1),流速1.0mL/m in,检测波长280nm,柱温30℃,进样量10μL。结果线性范围分别是:氯霉素49.82μg/mL~498.20μg/mL,r=0.9999;甲硝唑39.74μg/mL~397.40μg/mL,r=0.9999;平均回收率±RSD分别为99.42%±0.97%,99.83%±0.70%。结论本法简便,快速,准确,适用于该制剂中氯霉素和甲硝唑含量测定。     

HPLC法同时测定复方氯霉素滴眼液中醋酸泼尼松龙、氯霉素及其降解产物氯霉素二醇物的含量

目的:建立同时测定复方氯霉素滴眼液中氯霉素、醋酸泼尼松龙及其降解产物氯霉素二醇物含量的方法。方法:采用高效液相色谱法。色谱柱为Dionex Acclaim C_(18),流动相为0.1%庚烷磺酸钠溶液-冰乙酸-乙腈-甲醇(60∶0.2∶30∶10,V/V/V/V),流速为1.0 mL/min,检测波长为271 nm,柱温为30℃,进样量为10μL。结果:氯霉素、醋酸泼尼松龙、氯霉素二醇物检测质量浓度线性范围分别为11.73~703.71μg/mL(r=0.999 8)、12.40~744.06μg/mL(r=0.999 8)、1.03~62.03μg/mL(r=0.999 8);氯霉素二醇物的定量限为0.01μg/mL;精密度、稳定性试验的RSD<2.0%;氯霉素、醋酸泼尼松龙重复性试验的RSD<2.0%,氯霉素二醇物的RSD=4.5%;回收率分别为100.6%~102.7%(RSD=0.60%,n=9)、97.5%~100.3%(RSD=0.80%,n=9)、100.0%~103.2%(RSD=1.10%,n=9)。结论:该方法结果准确、操作简便,可用于复方氯霉素滴眼液中氯霉素、醋酸泼尼松龙及其降解产物氯霉素二醇物含量的同时测定。     

高效液相色谱法测定氯强油搽剂中氯霉素和醋酸泼尼松的含量

目的:建立高效液相色谱法测定氯强油搽剂中氯霉素和醋酸泼尼松的含量。方法:测定氯霉素含量用Spherisorb C18柱(4.6mm×250mm,5μm),流动相为甲醇-0.02mol.L-1磷酸二氢钾(用磷酸调pH至3.0)(60∶40,v/v),流速为0.9mL.min-1,检测波长为242nm;测定醋酸泼尼松含量用C18色谱柱(4.6mm×250mm,5μm),以甲醇-水(60∶40,v/v)为流动相,检测波长为240nm,流速为1.0mL.min-1。结果:氯霉素在100.1~500.4mg.L-1范围内线性关系良好(r=0.999 6),平均回收率为100.2%;醋酸泼尼松在10~150mg.L-1范围内线性关系良好,峰面积积分值与浓度呈良好线性关系(r=0.999 6);平均回收率为99.4%(RSD=1.7%)。结论:高效液相色谱法可以用于该制剂得含量测定和质量控制,方法简便、灵敏、结果准确。     

高效液相色谱法测定氯霉素地塞米松搽剂中二组份的含量

目的建立一种快速、准确的高效液相色谱法测定氯霉素地塞米松搽剂中的氯霉素和醋酸地塞米松含量的方法。方法色谱柱岛津VP-ODS(5μm,150mm×4.6mm)流动相:甲醇-水(70∶30);流速:1mL.m in-1;检测波长:240nm;柱温:室温;进样量:20μL。结果氯霉素进样量在5.00μg~30.00μg范围内线性良好,r=0.99999。平均回收率为99.70%,RSD=0.68%(n=9);醋酸地塞米松进样量在0.13μg~0.75μg范围内线性良好,r=0.99999。平均回收率为99.97%,RSD=1.38%(n=9)结论试验结果表明本法简便快速,重现性好,结果准确可靠,可以作为氯霉素地塞米松搽剂中氯霉素和醋酸地塞米松含量测定的方法。     

HPLC同时测定复方氯霉素乳膏中氯霉素和醋酸地塞米松的含量

目的:建立高效液相色谱法测定复方氯霉素乳膏(新复霜)中氯霉素和醋酸地塞米松的含量。方法:用十八烷基硅烷键合硅胶为填充剂[Symmetry C_(18)柱(4.6 mm×150 mm,5 μm)];以甲醇-水(64∶36)为流动相,流速为0.5 mL·min~(-1);检测波长为240 nm;进样量5 μL。结果:氯霉素及醋酸地塞米松在231.3～809.5μg·mL~(-1)(r=0.9999)和14.1～84.6μg·mL~(-1)(r=0.9999)范围内呈良好的线性关系;氯霉素和醋酸地塞米松精密度 RSD 分别为0.16%和0.22%;平均回收率(n=9)分别为100.1%和99.55%。结论:本方法快速、简便,重现性好,结果可靠,可作为复方氯霉素乳膏的质量控制标准。     

高效液相色谱法与紫外光谱法测定索拉非尼原料药含量的比较

目的 分别采用高效液相色谱(HPLC)法与紫外分光光度(UV)法对相同批号的索拉非尼原料药进行含量测定并进行比较.方法 高效液相色谱法中,色谱柱为Inertsil ODS-3柱(250 mm×4.6 mm,5 μm),流动相为乙酸铵缓冲液(50 mmol/L)-乙腈(28:72),检测波长为265 nm,流速为1.0 mL/min,柱温为40℃,进样量为50μL.紫外分光光度法中,索拉非尼原料药样品溶液用甲醇配制,在265 mm波长处进行测定.结果 高效液相色谱法测得索拉非尼进样质量浓度在0.5～40 μg/mL(r=0.99999)范围内与峰面积线性关系良好,平均加样回收率为102.92%,RSD=1.30%(n=9).紫外分光光度法测得索拉非尼进样质量浓度线性范围是0.1～20 μg/mL(r=0.999 9).紫外分光光度法含量测定结果比高效液相色谱法平均高出1.067倍.结论 紫外分光光度法不适用于准确测定索拉非尼原料药的含量.高效液相色谱法的专属性好、稳定性、精密度以及加样回收率都较好,适用于索拉非尼原料药含量的准确测定.     

HPLC法测定复方氯霉素乳膏中氯霉素和丙酸倍氯米松含量

目的:建立测定复方氯霉素乳膏中氯霉素和丙酸倍氯米松含量的方法。方法:采用高效液相色谱法。色谱柱为Shim-pack VP-ODS,流动相为含乙腈-0.05mol.L-1磷酸二氢钾溶液,梯度洗脱,流速为1.0mL.min-1,检测波长为240nm,进样量为15μL。结果:氯霉素和丙酸倍氯米松检测浓度线性范围分别为47.6～238、2.96～14.8μg.mL-1(r=0.9999、0.9998),平均回收率分别为99.97%(RSD=0.84%,n=9)、99.28%(RSD=1.87%,n=9)。结论:本法简便、准确,可用于复方氯霉素乳膏的含量测定。     

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.     

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.     

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.     

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.