棕榈氯霉素卵磷脂O/W型微乳制剂的研究

目的 棕榈氯霉素卵磷脂O/W型微乳制剂的制备与含量检测。方法 用十六酸异丙酯溶解棕榈氯霉素作油相,卵磷脂和吐温₈₀混合作为表面活性剂,乙醇为助表面活性剂,制备O/W型微乳制剂;用高效液相色谱法进行棕榈氯霉素含量的测定。色谱条件:C₁₈柱(250 mm×4.60 mm,5μm),流动相为甲醇液,柱温25℃,流量为1.0 ml·min^-1,检测波长为271 nm,进样体积20μl。结果 取得了较好的棕榈氯霉素卵磷脂O/W型微乳制剂及较好的含量检测方法。讨论 棕榈氯霉素可以制成卵磷脂O/W型微乳制剂,用高效液相色谱法进行含量测定。     

微乳液相色谱法及其研究进展

微乳是由表面活性剂、油相、助表面活性剂、水相在适当比例下自发形成的一种透明或半透明的、低黏度的、各向同性且热力学稳定的水油混合系统。油相液滴（droplets）包裹于表面活性剂和助表面活性剂层并均匀分散在水相中,形成O／W型微乳;表面活性剂包裹水性液滴并分散在油相体系中形成W／O型微乳。微乳的研究主要集中在药剂学方面,用于药物分析方面的研究还比较少。微乳的粒径通常小于100nm,用于色谱流动相的微乳粒径可以小于10nm。微乳可以作为薄层色谱的展开剂和毛细管电泳的分离介质,也可以作为高效液相色谱的流动相,通常我们将以微乳为流动相的高效液相色谱法称为微乳液相色谱法（microemulsion liquid chromatography,MELC）。     

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法测定棕榈氯霉素B型片含量

目的：建立高效液相色谱法，测定棕榈氯霉素(B)型片中的棕榈氯霉素含量。方法：用C8柱，lmol／L醋酸溶液-甲醇(18：82)N流动相，检测波长273nm。结果：进样量在2．0～3．0μg范围内与主峰面积线性关系良好(r=0．9997)，平均回收率100.0％(RSD0.73％)，重复进样RSD0．50％(n=6)，主峰与氯霉素峰分离度31．9。结论：本法用于测定棕榈霉素(B)型片中棕榈氯霉素含量专属性强，可排除游离氯霉素等有关物质的影响，测定准确快速。     

草乌甲素微乳的制备及其理化性质的考察

目的 选择适宜比例的油相、表面活性剂、助表面活性剂和水相,制备草乌甲素微乳制剂,以增加药物的溶解度,优化处方,并研究其理化性质.方法 绘制伪三元相图,确定各相的比例,以微乳区域大小为指标,考察优化微乳的处方.测定草乌甲素微乳的粒度及其分布.结果 草乌甲素微乳制剂中药物的溶解度极大提高,乳液滴的平均粒径为53.6 nm.结论 制备了O/W型草乌甲素微乳,为开发草乌甲素透皮制剂提供了依据.     

水包油型微乳形成因素的考察

目的考察影响O/W型微乳形成的主要因素。方法选用丁酸乙酯、油酸乙酯和豆油作为油相 ,Tween 80、Tween 2 0和Labrasol作为表面活性剂 ,乙醇、1,2 -丙二醇和正丁醇为助表面活性剂 ,通过滴加法绘制假三元相图 ,以O/W型微乳区大小为指标考察各因素对微乳形成的影响。结果油相、表面活性剂、助表面活性剂、表面活性剂与助表面活性剂的质量比、离子强度、添加剂和温度对微乳的形成均有一定影响。结论O/W型微乳能够作为药用载体。     

HPLC法测定维生素E尿囊素乳膏中维生素E与尿囊素含量

目的采用高效液相色谱法测定维生素E尿囊素乳膏中维生素E与尿囊素的含量。方法采用高效液相色谱法。维生素E用C18柱,以甲醇为流动相,流速1.5 mL/min,检测波长284 nm;尿囊素用ZOR-BAX NH3柱,以甲醇:水=80∶20为流动相,流速1.0 mL/min,检测波长为224 nm。结果维生素E线性范围29.32~175.92μg/mL,r=0.999 99,平均回收率为98.89%,RSD=1.54%(n=9);尿囊素线性范围187.68~938.40μg/mL,r=0.999 95,平均回收率为99.90%,RSD=1.92%(n=9)。结论本品制备简单,含量测定用高效液相色谱法,测定方法专属性强,结果准确可靠,并能很好地控制制剂质量。     

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。     

复方尿囊素乳膏的制备及含量测定

目的:研制尿囊素的皮肤科新制剂,并建立含量测定方法。方法:采用高效液相色谱法测定含量。用C_(18)柱以甲醇-0.03mol/L磷酸二氢钠液(40:60)为流动相,流速0.5ml·min~(-1)检测波长217nm。结果:尿囊素线性范围40.96～204.80μg·ml~(-1),r=0.9994,平均回收率100.7％,RSD为0.5％(n=6)。结论:本品制备简单,含量测定用高效液相色谱法,测定方法专属性强,结果准确可靠,并能很好地控制制剂质量。     

灯盏花素口服微乳的制备

目的制备灯盏花素口服微乳并建立其包裹率测定方法。方法采用单因素法及伪三元相图法优选处方,葡聚糖凝胶柱层析法分离含药微乳与游离药物,以纯化水为洗脱液,高效液相色谱法测定药物含量。结果优选的油相、表面活性剂及助表面活性剂分别为油酸乙酯、聚山梨酯80及聚乙二醇400。柱层析分离方法药物回收率100.37%,加样回收率97.9%,药物含量测定方法回收率99.94%,线性范围12～360 μg• mL－1。样品包封率（93.2±1.0）%。结论所建立的方法可用于制备灯盏花素口服微乳并测定其包裹率。     

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.

---

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.     

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.     

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.