阿克他利固体脂质纳米粒的制备

目的以乳化蒸发一低温固化法制备阿克他利固体脂质纳米粒。方法在单因素考察的基础上以正交试验设计优化、筛选最佳处方和制备工艺。用透射电镜观察固体脂质纳米粒的形态，激光散射测定Zeta电位和粒度分布，高速离心法测定阿克他利固体脂质纳米粒的包封率。结果所制固体脂质纳米粒外观形态圆整，粒度分布为50～200am，平均粒径为120am，Zeta电位为一17．14mV，包封率为50．87％。结论阿克他利固体脂质纳米粒的制备，为开发阿克他利静脉注射被动靶向制剂奠定了试验基础。     

薄膜-超声法制备芦丁固体脂质纳米粒的研究

目的优化薄膜-超声法制备芦丁固体脂质纳米粒的处方。方法以包封率为指标,采用正交设计优化法考察硬脂酸和大豆卵磷脂的用量、吐温-80和聚乙二醇-400的体积分数对包封率的影响,优选最佳处方。用透射电镜观察外观形态,用电位/纳米粒度分析仪分析纳米粒的粒径及Zeta电位,用透析法评价体外释药特征。结果以最佳处方制备的芦丁固体脂质纳米粒呈类球形,平均粒径为195.8±11nm,Zeta电位为-20.65±0.6mV,平均包封率为86.31%,72h体外累积释放87.32%。结论按最佳处方工艺制备的芦丁固体脂质纳米粒具有较高的包封率和较好的缓释效果。     

阿克他利固体脂质亚微粒处方组成与制备工艺

目的:优选简便且重现性好的乳化蒸发-低温固化法制备阿克他利固体脂质亚微粒。方法:正交试验设计优化,筛选最佳处方和制备工艺。透射电镜观察固体脂质亚微粒的形态,激光散射测定Zeta电位和粒度分布,高速离心法测定阿克他利固体亚微粒的包封率。结果:所制固体脂质亚微粒外观形态圆整,粒度分布为50～200 nm,平均粒径为120 nm。Zeta电位为-17．14 mV,包封率为51．20％。结论:阿克他利固体脂质亚微粒的制备,为开发阿克他利静脉注射被动靶向制剂提供试验基础。     

5-氟尿嘧啶聚乙二醇-聚十六烷基氰丙烯酸酯纳米粒的制备

目的:以聚乙二醇-聚十六烷基氰丙烯酸酯(PEG-PHDCA)聚合物制备5-氟尿嘧啶(5-Fu)纳米粒,并对其进行体外释药研究.方法:采用溶剂扩散法制备5-Fu PEG-PHDCA纳米粒,在单因素基础上采用正交设计法优化得到最佳处方,并对5-Fu聚合物纳米粒的粒径、Zeta电位、载药量、包封率和体外释放进行了研究.结果:制得的5-Fu聚合物纳米粒的平均粒径为132 nm,Zeta电位为-(12±2)V,载药量为12.3%,包封率为48.8%.体外释放研究发现,5-Fu PEG-PHDCA纳米粒释药近似符合Higuchi释药模型:Q=0.564 4+8.386t1/2(r=0.996 0).结论:采用溶剂扩散法制备5-Fu聚合物纳米粒方法简单,重现性好,其体外释放显示出明显缓释作用.     

正交设计优化伊曲康唑固体脂质纳米粒的处方组成与制备工艺

目的:制备伊曲康唑固体脂质纳米粒(itraconazole solid lipid nanoparticles,ITZ-SLNs)并对其进行物相分析以确定纳米粒的形成。方法:以伊曲康唑(ITZ)为模型药物,硬脂酸为载体材料,采用乳化-低温固化法制备伊曲康唑固体脂质纳米粒(ITZ-SLN),正交试验设计优化处方组成和制备工艺,并对纳米粒的结构形态、粒径、表面电位、包封率、体外释药特性等进行了研究。结果:以优化处方制备的伊曲康唑固体脂质纳米粒为类球形实体,粒径分布比较均匀,平均粒径为dav=(118.2±15.00)nm,Zeta电位为-(37.06±0.53)mV,包封率为(92.11±1.60)%,药物体外释放符合Higuchi方程,经DSC分析证明纳米粒确已形成。结论:伊曲康唑固体脂质纳米粒有望成为新型缓释纳米给药系统。     

槲皮素固体脂质纳米粒的制备

目的: 制备槲皮素固体脂质纳米粒并对其理化性质进行考察。方法: 采用乳化蒸发-低温固化法制备槲皮素固体脂质纳米粒,以正交设计优化处方和制备工艺,超滤法测定包封率,透射电子显微镜对其粒子形态进行观察,并使用激光粒度分析仪测定其粒径和Zeta电位。结果: 经处方优化制备的固体脂质纳米粒平均粒径为(124.2±0.371) nm,Zeta电位为(-22.3±0.315) mV,粒子形态均匀,无粘连,平均包封率为(89.3±1.209)%。结论: 制备槲皮素固体脂质纳米粒的工艺简便可行,包封率较高且纳米粒质量优良。     

蓝萼甲素固体脂质纳米粒的制备及理化性质研究

目的:制备蓝萼甲素固体脂质纳米粒,并对其理化性质进行研究。方法:用乳化-溶剂挥发法制得蓝萼甲素固体脂质纳米粒,并对其粒径、形态、表面电位、包封率、体外释药性质等进行研究。结果:所得蓝萼甲素固体脂质纳米粒的粒径分布均匀,平均粒径为(190±10·3)nm,Zeta电位为—31·2mV,平均包封率为(50·45±0·804)%;药物体外释放符合Higuchi线性方程,具有显著缓释作用。结论:固体脂质纳米粒可作为蓝萼甲素新型缓释给药系统。     

CA4固体脂质纳米粒的制备及体外释药特性的考察

目的 制备CA4固体脂质纳米粒(CA4-SLNs),并考察其理化性质及体外释药特性.方法 通过乳化蒸发-低温固化法制备CA4-SLNs,用透射电镜观察形态,激光粒度仪测定粒径和ξ电位,HPLC法测定包封率与载药量,透析法考察其体外释药特性.结果 CA4-SLNs在透射电镜下呈球形或类球形,分布均匀,平均粒径为73.23nm,PDI为0.238,Zeta电位为-30.5 mV;测得3批CA4-SLNs样品的平均包封率为98.62%,载药量为3.89%;体外释药符合Weibull模型:lnln[1/(1-Q)]=0.6123Int-0.736(r=0.9917).结论 乳化蒸发-低温固化法适用于CA4-SLNs的制备,所制纳米粒的包封率较高,释药初期稍有突释,后即出现缓释.     

大黄素固体脂质纳米粒的制备及理化性质研究

目的：制备大黄素固体脂质纳米粒,并对其理化性质进行研究。方法：用乳化一溶剂挥发法制得大黄素素固体脂质纳米粒,并对其粒径、形态、表面电位、包封率、体外释药性质等进行研究。采用全体液平衡反向透析法研究体外释药性质。结果：所制固体脂质纳米粒外观形态圆整,粒度分布均匀,平均粒径为253nm,电位为一25．4mV,包封率为（56．31±2．06）％。药物体外释放符合Weibull线性方程。结论：固体脂质纳米粒可作为大黄素新型缓释给药系统。     

马钱子碱固体脂质纳米粒制备及质量评价

目的：以乳化蒸发-低温固化法制备马钱子碱固体脂质纳米粒并评价其质量。方法：在单因素考察的基础上以正交试验设计优化、筛选最佳处方。用透射电镜观察固体脂质纳米粒的形态,HPLC法测定马钱子碱固体脂质纳米粒的包封率,激光散射测定Zeta电位和粒度分布,并考察其稳定性。结果：所制固体脂质纳米粒外观形态圆整,平均粒径为116nm,Zeta电位为-29．98mv,包封率为50．7％,载药量为2．25％。4℃放置1个月,粒径、包封率无明显变化。结论：本研究制备的马钱子碱固体脂质纳米粒粒径分布窄,稳定性好,为开发马钱子碱低毒长效的制剂奠定了实验基础。     

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.