HPLC法同时测定氯霉素氢化可的松搽剂中氯霉素和氢化可的松的含量

目的 建立同时测定氯霉素氢化可的松搽剂中氯霉素和氢化可的松的含量测定方法.方法 采用高效液相色谱法.色谱柱为Agilent TC-C18,流动相为甲醇-水(60∶40),流速为1mL·min-1,检测波长为240nm.结果 氯霉素和氢化可的松浓度分别在19.06～762.36μg·mL-1和2.01～80.52μg·mL-1内线性关系良好,r分别为0.9997和0.9999;平均回收率分别为101.8%和102.0%,RSD分别为1.46%和1.24%(n=9).结论 该方法简单、快速、准确,可用于同时测定氯霉素氢化可的松搽剂中氯霉素和氢化可的松的含量.     

双波长分光光度法测定氯霉素氢化可的松滴耳液中氢化可的松的含量

应用双波长分光光度法测定氯霉素氢化可的松滴耳液中氢化可的松含量。以乙醇、聚乙二醇_(400),丙二醇的混合液为溶剂,在波长247、309nm处进行测定。结果氢化可的松浓度在2～12μg·ml~(-1)之间,浓度与吸收度差值呈良好的线性关系。氢化可的松平均回收率为99.7％,RSD为0.7％(n=9)。该方法简便、快速、准确可靠     

高效液相梯度洗脱法测定尿中氢化可的松和可的松含量

目的测定尿中氢化可的松与可的松的比值以表达人体肾脏11β-羟化类固醇脱氢酶活性,为其研究提供一个准确、精密、重现性好的分析手段。方法HPLC-UV法,梯度洗脱,内标定量。结果尿中氢化可的松和可的松在10～100.0ng.ml     

旋光法测定氢化可的松二甲基亚砜溶液中氢化可的松的含量

氢化可的松二甲基亚砜溶液（氢可溶液决医院常用的皮肤科外用制剂，有消炎、止痛及抗过敏作用，主要用于神经性皮炎、腰肌劳损等症。因疗效确切被收载在《中国医院制剂规范》西药制剂第二版。处方组成为氢化可的松2g（另一规格为5g），二甲基亚砜600ml，蒸馏水加至1000ml。氢化可的松规定的含量测定方法为紫外分光光度法，测定波长为238um，二甲基亚砜在该波长亦有较大吸收，并随浓度变化而变化［1］。方法中以60％二甲基亚砜的醇溶液为空白，以去除二甲基亚砜的干扰。在制剂过程中，为了加速溶解过程，必须先将氢化可的松用二甲基亚砜全部…     

高效液相色谱法测定尿中氢化可的松和6β-羟基氢化可的松的含量

目的:建立测定尿液中氢化可的松和6β-羟基氢化可的松含量的方法.方法:尿样9 mL以5 mL醋酸乙酯-乙醚(4∶1)提取后,有机相以氮气吹干,以甲醇溶解后进样,检测波长为240 nm.结果:6β-羟基氢化可的松和氢化可的松标准曲线方程分别为Y=0.033X-0.007,r=0.998 9和Y=0.067X 0.002,r=0.999 6;两者的回收率分别为98.56%和99.45%;RSD分别为4.47%和3.85%.10例健康志愿者的定时尿中6β-羟基氢化可的松和氢化可的松的含量分别为(194.1±66.8) μg·L-1和(24.0±9.4) μg·L-1.两者之间的比值为(8.5±2.9).结论:本法灵敏可靠,符合人体尿样中6β-羟基氢化可的松和氢化可的松测定的要求.     

氢化可的松片含量测定方法的研究

目的：氢化可的松片含量测定,中国药典均采用无水乙醇为溶剂,在波长242nm处测定吸收度,计算含量。本文采用水为溶剂用紫外分光光度法测定氢化可的松片的吸收度,计算含量。方法：采用紫外分光光度法测定。结果：氢化可的松在氢化可的松浓度在5-20μg/mL范围内与吸收度有良好的线性关系。结论：本法简便,准确。     

双波长分光光度法测定氯霉素氢化可的松滴耳液中氢化可的松的含量

应用双波长分光光度法测定氯霉素氢化可的松滴耳液中氢化可的松含量。以乙醇、聚乙二醇₄₀₀,丙二醇的混合液为溶剂,在波长247、309nm处进行测定。结果氢化可的松浓度在2～12μg·ml^-1之间,浓度与吸收度差值呈良好的线性关系。氢化可的松平均回收率为99.7％,RSD为0.7％(n=9)。该方法简便、快速、准确可靠。     

氢化可的松片含量测定方法的研究

目的:探讨以水为溶剂采用紫外分光光度法测定氢化可的松片的吸收度及含量方法的可靠性.方法:采用紫外分光光度法测定氢化可的松片的含量.结果:氢化可的松浓度5～20 μg/mL范围内与吸收度有良好的线性关系.结论:以水为溶剂用紫外分光光度法在248 nm的波长处测定氢化可的松片的吸收度,计算含量.本法简便,准确.     

内源性氢化可的松为探针的体内CYP3A活性测定

目的建立测定精神病患者体内CYP3A酶活性的方法。方法直接收集20例精神病住院患者晨尿液,测定尿液中内源性氢化可的松与6β-羟基氢化可的松的含量,以6β-羟基氢化可的松/氢化可的松来评估CYP3A酶的活性。结果患者尿液中6β-羟基氢化可的松与氢化可的松的比值为(8.12±4.36)。结论CYP3A酶的活性可以通过测定6β-羟基氢化可的松与氢化可的松的比值进行预测。     

紫外分光光度法测定氯霉素氢化可的松滴耳液的含量

氯霉素氯化可的松滴耳液系由氯霉素、氢化可的松、乙醇、聚乙二醇400、丙二醇组成的复方制剂，有抗炎、抗过敏作用，用于中耳炎等症，为常用的医院制剂之一。中国医院制剂规范以分光光度法测定处方中氯霉素含量（以下称规范法），而无氢化可的松的含量控制方法［1］，为进一步控制制剂质量从而更好地为临床提供质量优良的制剂，本文根据处方中各组分的紫外吸收特性以双波长分光光度法［2］测定制剂中氢化可的松的含量，并同时测定氯霉素含量，方法简便，结果准确。1．仪器与药品：752型紫外光栅分光光度计，山东高密分析仪器厂。氯霉素、氢…     

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.     

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.     

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.