那格列奈的新晶型

目的　确证降糖药那格列奈另一种新的晶型结构,称为S型。给出X射线衍射、红外图谱和相关数据。方法　用X射线粉末衍射、红外光谱、元素分析和差示扫描量热法作物相分析。结果　S型那格列奈有与文献报道的H型、B型完全不同的晶型。mp 172.04℃。结论　S型那格列奈是一种新的晶型     

那格列奈的多晶型及转化

目的：研究那格列奈的多晶型及相互转化。方法：采用了不同的溶剂、不同的温度以及研磨等晶型转化方法，晶型判定方法为X-射线粉末衍射法。结果：发现了另外一种那格列奈的新晶型，命名为X2型，并发现，H型可转变为X2型，X2型可转变为B型，H型、X2型、B型可转变为S型，H型、S型、B型可转变为无定型。结论：那格列奈的各晶型之间可以相互转化同时确立了几种晶型之间相互转化的条件。     

盐酸拓扑替康的晶型与稳定性研究

目的解析不同晶型盐酸拓扑替康理化性质变化以及稳定性。方法采用X射线衍射、热分析、红外分光光度法、高效液相色谱法。结果发现4种晶型的存在,4种晶型的熔点、X射线衍射图、红外吸收光谱图均有差异,其稳定性也存在差异。结论不同晶型的盐酸拓扑替康理化性质有差异,稳定性也存在差异,以B晶型最稳定。     

马来酸替加色罗的晶型研究

目的：研究马来酸替加色罗2种晶型的物理性质。方法：运用傅立叶变换红外光谱、拉曼光谱、热分析和粉末X-射线衍射法研究马来酸替加色罗的晶型。结果：运用不同的重结晶溶剂，马来酸替加色罗可形成2种晶型，这2种晶型的熔点一致，它们的DSC和TG曲线都相同。但他们的红外光谱、拉曼光谱和粉末X-射线衍射图谱均存在着差异。结论：红外光谱、拉曼光谱和粉末X-射线衍射图谱可作为鉴别马来酸替加色罗晶型的方法。     

葛根素的多晶型研究

目的：解析不同晶态葛根素的理化性质变化。方法：采用4种不同溶剂进行结晶，应用显微放大、溶解度、红外、X射线衍射、热分析。结果：不同晶态的晶体在水中的溶解度随着晶型的增大而减小；热分析显示4种晶体的熔点存在差异；X射线衍射测得4种晶体的厚度不一样，特别是用乙醇水结晶的样品结晶度最低；红外谱图显示4种晶体有差异，并且超临界流体结晶所得样品和标准红外谱图一致。结论：不同晶态的葛根素其理化性质有明显差异。     

托伐普坦的结构确证和晶型探讨

目的验证所合成的化合物为目标产物托伐普坦,并通过X射线衍射技术探讨其晶型。方法选择适宜的条件,培养出适合单晶X射线衍射分析的单晶体,对所得单晶数据进行结构解析,得到化合物的三维空间结构信息;同时通过单晶结构数据模拟获得化合物的粉末X射线衍射理论图谱,用于晶型研究。结果单晶X射线衍射结构分析结果表明,合成的托伐普坦的化学结构、构型与文献报道完全一致;粉末X射线衍射理论图谱可作为晶型对照图谱使用,并进一步表明托伐普坦存在多晶型现象。结论单晶X射线衍射分析法可准确测定内消旋托伐普坦的空间结构,充分证实了该药物合成结果的正确性,粉末X射线衍射理论图谱可为化合物的晶型研究提供有力支持。     

氨基葡萄糖盐酸盐晶型的初步研究

目的研究氨基葡萄糖盐酸盐的多晶型现象。方法采用熔点测定、粉末X射线衍射(XRD)、单晶X射线衍射、差示扫描量热分析(DSC)、热重分析(TGA)等技术对样品晶型进行测定分析。结果各晶体熔点、XRD、DSC等数据均表现明显差异性。结论氨基葡萄糖盐酸盐存在多晶型现象。     

帕拉米韦及其中间体酯化物结构的X射线衍射分析

目的 验证所合成的化合物为目标产物——帕拉米韦中间体酯化物及帕拉米韦成品,并通过X射线衍射技术探讨化合物晶型.方法 选择适宜的条件,培养出适合单晶X射线衍射分析的单晶体,对所得单晶数据进行结构解析,得到化合物的三维空间结构信息,与文献进行比对;同时通过单晶结构数据模拟获得化合物的粉末X射线衍射理论图谱,用于晶型研究.结果 单晶X射线衍射结构分析结果表明,帕拉米韦中间体酯化物及成品的化学结构、构型与文献报道完全一致:粉末X射线衍射理论图谱可作为晶型对照图谱使用,并进一步表明中间体存在多晶型现象.结论 单晶X射线衍射分析法可准确测定含多手性中心的帕拉米韦中间体酯化物及成品的空间结构,充分证实了该药物合成过程与结果的正确性;粉末X射线衍射理论图谱可为化合物晶型研究提供有力支持.     

(S)-N-环氧丙基邻苯二甲酰亚胺的单晶制备及其表征

目的制备(S)-N-环氧丙基邻苯二甲酰亚胺的单晶,并对其进行结构表征和均浆稳定性研究。方法通过溶剂挥发法和气相扩散法制备(S)-N-环氧丙基邻苯二甲酰亚胺晶型。利用差示扫描量热仪(DSC)、热重分析仪(TGA),红外光谱仪(IR),粉末X射线衍射仪(PXRD)和单晶X射线衍射仪(SXRD)分别对制备得到的晶体样品进行表征。结果制备得到的(S)-N-环氧丙基邻苯二甲酰亚胺晶体样品,其DSC、TGA、IR和PXRD图谱均一致,即晶型一致;DSC结合TGA分析结果显示,(S)-N-环氧丙基邻苯二甲酰亚胺熔点为100.56℃,分解温度为128.2℃。单晶X射线衍射结果表明该晶胞属于单斜晶系,P2_1空间群,结构偏离因子R=0.04,分子式为C_(11)H_9NO_3,相对分子质量为203.19,立体构型与预测构型一致。均浆稳定性实验结果表明,不同极性溶剂中得到的晶体粉末X射线未发生变化,即晶型稳定性良好。结论实验确证了(S)-N-环氧丙基邻苯二甲酰亚胺的立体结构,且晶型稳定性良好。     

多晶型消炎痛的家兔消化道吸收的药物动力学研究

非甾体抗炎药消炎痛,具有三种晶型。作者将消炎痛进行重结晶,采用红外光谱和X-射线衍射方法确证为α型(熔点154.5～155.5°)和γ型(熔点160°～161.5°)两种晶型,并通过200目筛。实验雄性白家兔,用正交法口服给药,样品制成悬浮液,剂量为24mg/     

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.