星点设计效应面法优化耐冻融茴三硫口服纳米乳剂的处方

目的借助星点设计效应面法优化耐冻融茴三硫口服纳米乳剂的最优处方。方法采用超声波细胞粉碎仪制备茴三硫口服纳米乳剂,依据星点设计效应面法,以平均粒径、变异系数及冻融稳定性常数为评价指标,考察处方中聚氧乙烯40氢化蓖麻油、大豆卵磷脂及中链甘油三酸酯的用量对制剂的影响,预测最优处方。结果最优处方制得的茴三硫口服纳米乳剂的平均粒径为(163.7±0.3)nm,变异系数为0.290±0.035,冻融稳定性常数为1.84±0.03,与预测值相比偏差较小。结论星点设计效应面法所建立的模型能较好地用于茴三硫口服纳米乳剂的处方优化。     

星点设计-效应面法优化低密度脂蛋白纳米粒处方与制备工艺

目的 研制低密度脂蛋白纳米粒,优选其处方与制备工艺.方法 采用薄膜-超声法制备脂微乳,连接含载脂蛋白apoprotein B-100中、低密度脂蛋白受体结合域序列的合成肽制备纳米粒.以脂质浓度、超声功率及超声时间为考察因素,粒径为指标,采用星点设计-效应面法优化其处方及制备工艺.结果 优选的脂质浓度为0.1％;超声功率为380 w,超声时间为6h.制备的纳米粒平均粒径为27.7 nm,PDI为0.17,ζ-电位为-28.7 mV.结论 采用星点设计-效应面法优化低密度脂蛋白纳米粒的处方与制备工艺,制备的纳米粒粒径与预测值接近,表明用该法优化其处方与制备工艺可行.     

星点设计-效应面法优化细叶远志皂苷自微乳释药系统

目的 采用星点设计-效应面法优化细叶远志皂苷自微乳处方.方法 配伍试验、绘制伪三元相图进行处方筛选,以溶解度、粒径及乳化时间为指标,星点设计-效应面法优化处方.结果 细叶远志皂苷自微乳的处方配比为油酸乙酯12.93%,RH40 56.30%,1,2-丙二醇30.77%.结论 此方法的预测性良好,适用于细叶远志皂苷自微乳的处方优化.     

星点设计-效应面法优化葫芦素口服脂质纳米乳剂的处方

目的借助星点设计-效应面法确定葫芦素口服脂质纳米乳剂的最优处方。方法提出了2个量化乳剂稳定性的常数:灭菌稳定性常数KS和冻融稳定性常数KF。用微射流仪制备葫芦素口服脂质纳米乳剂,采用星点设计-效应面法,以葫芦素口服脂质纳米乳剂的平均粒径(Y1)、灭菌稳定性常数KS(Y2)及冻融稳定性常数KF(Y3)为评价指标,考察了葫芦素口服脂质纳米乳剂处方中聚氧乙烯40氢化蓖麻油的用量(X1)、大豆卵磷脂的用量(X2)及中链脂肪酸甘油三酯的用量(X3)对制剂的影响,以效应面法预测最佳处方。结果优选的最优处方为:m(聚氧乙烯40氢化蓖麻油)∶m(大豆卵磷脂)∶m(中链脂肪酸甘油三酯)=1.15∶0.50∶5.52。采用优化处方制得的葫芦素口服脂质纳米乳剂的平均粒径为(113.6±2.1)nm,灭菌稳定性常数KS为2.92±0.7,冻融稳定性常数KF为5.14±0.2,同预测值的偏差均较低,最大偏差为4.6%。结论星点设计-效应面法所建立的模型能较好地应用于葫芦素口服脂质纳米乳剂处方的优化。     

Box-Behnken设计-效应面法优化甘草黄酮纳米混悬处方

目的:制备甘草黄酮纳米混悬剂,优化其制备工艺及处方。方法:采用沉淀法-高压均质法联合制备甘草黄酮混悬剂。以平均粒径为响应值,单因素试验和Box-Behnken设计-效应面法优化甘草黄酮纳米混悬剂处方,并对处方进行验证。结果:对试验结果进行模型拟合,采用Box-Behnken设计-效应面法优化甘草黄酮纳米混悬处方,按最优处方制得带乳光的棕黄色溶液,其粒径为(179.7±0.907)nm,PDI为0.274±0.012。结论:Box-Behnken设计-效应面法适用于甘草黄酮纳米混悬剂的处方优化,优化得的处方具良好的预测性。     

正交设计联用星点设计-效应面法优化蒿甲醚长循环纳米结构脂质载体处方

目的采用正交设计联用星点设计-效应面法优化蒿甲醚长循环纳米结构脂质载体处方。方法先采用正交设计进行蒿甲醚长循环纳米结构脂质载体处方主要影响因素的初步筛选,再采用星点设计-效应面法进一步优化处方,以固液脂质质量比、PEG占脂质的质量分数、药物占脂质的质量分数为考察因素,以包封率、平均粒径、zeta电位、总评"归一化"值为考察指标,对结果进行多元线性回归、多元非线性拟合,经效应面法预测最佳处方。结果优化处方制备的蒿甲醚长循环纳米结构脂质载体的包封率为99.3%,平均粒径为29.2 nm,zeta电位为-37.2 m V。结论采用正交设计联用星点设计-效应面法建立的数学模型,较好地预测了蒿甲醚长循环纳米结构脂质载体的处方优化,根据优化处方制得的蒿甲醚长循环纳米结构脂质载体的包封率、粒度及zeta电位等达到预期目标。     

星点设计效应面法优化维生素K_2口服亚微乳的处方

目的借助星点设计效应面法确定维生素K_2口服亚微乳的最优处方。方法采用微射流法制备维生素K_2口服亚微乳;采用星点设计效应面法,以乳剂的平均粒径(mean diameter,MD)、变异系数(coefficient of variation,CV)、离心稳定性常数(centrifugal stability contant,K_E)和冻融稳定性常数(freeze-thawing stability constant,K′_F)为评价指标,考察处方中聚氧乙烯40氢化蓖麻油、大豆卵磷脂及中链甘油三酸酯的用量对制剂的影响,预测最优处方。结果优选的最优处方为m(聚氧乙烯40氢化蓖麻油):m(大豆卵磷脂):m(中链甘油三酸酯)=2.0∶0.5∶5.0。采用最优处方制得的维生素K_2口服亚微乳平均粒径为(104.7±2.4)nm,变异系数为0.441±0.090,离心稳定性常数为3.20±0.43,冻融稳定性常数为2.05±0.21,实验结果与预测值相比偏差较小。结论星点设计效应面法所建立的模型能较好地用于维生素K_2口服亚微乳的处方优化。     

运用Box—Behnken设计-效应面法对尼莫地平纳米乳剂处方工艺的优化

目的：运用Box—Behnken设计-效应面法优化尼莫地平纳米乳剂的处方工艺。方法：采用微射流法制备尼莫地平纳米乳剂,分别以聚氧乙烯蓖麻油（CremophorEL）的用量（X1）、大豆卵磷脂（SPC）的用量（X2）和中链脂肪酸甘油三酯（MCT）的用量（X3）为考察对象,以平均粒径（MD）（Y1）、粒径分布（CV）（Y2）为评价指标,运用三因素三水平Box．Behnken设计．效应面法筛选尼莫地平纳米乳剂的最佳处方工艺。结果：尼莫地平纳米乳剂的最优处方用量为X1=3．68％,X2=2．96％,X3=8．6％;按此处方用量制得的尼莫地平纳米乳剂,其平均粒径为（63．3±3．4）nm,粒径分布为（O．26±0．03）％。结论：运用Box—Behnken设计-效应面法优化尼莫地平纳米乳剂的处方工艺是可行的。     

星点设计-效应面法优化齐墩果酸乳铁蛋白纳米粒的处方

目的：采用星点设计-效应面法优化齐墩果酸乳铁蛋白纳米粒的处方,并对所制样品进行表征和体外溶出行为考察。方法：以乳铁蛋白浓度、pH值和药辅比为考察因素,粒径、Zeta电位、包封率为评价指标,采用多元线性回归及二次多项式回归建立指标与因素之间的数学关系,经效应面法预测最优处方并验证,对所得纳米粒制剂进行透射电镜及体外溶出度试验。结果：各项指标均以二次多项式方程拟合度最高（R2>0.98）且预测值与实测值吻合度较好,所制样品的平均粒径为（203.4±8.3） nm,Zeta电位为（27.1±2.3） mV,包封率为（92.6±3.2）%;表征结果显示纳米粒外观呈类球形;与原料药相比,纳米制剂溶出速率显著提高。结论：星点设计-效应面法适用于齐墩果酸乳铁蛋白纳米粒的处方优化筛选,并为进一步的体内生物利用度研究奠定了基础。     

星点设计-效应面法优化苯扎贝特渗透泵片处方

目的:制备苯扎贝特渗透泵片,运用星点设计-效应面法优化处方。方法:选择渗透泵片辅料聚氧乙烯(PEO)N80处方用量(A)、Na2CO3用量(B)和包衣增重(C)为考察因素,以该片在1h、6h的累积释药量以及累积释放量对时间进行线性拟合的相关系数为考察指标,采用星点设计-效应面法优化处方,并进行优化处方验证。结果:优化处方为A40mg、B20mg、C29mg,以该优化处方制备的渗透泵片具有较好的释药行为,各指标偏差的绝对值均小于5%。结论:星点设计-效应面法可用于苯扎贝特渗透泵片的处方优化,所建模型具有良好的预测能力。     

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.     

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.