替硝唑结肠定位肠溶片在家犬的药代动力学研究

目的　研究家犬口服替硝唑结肠定位肠溶片的药代动力学特征。方法　实验家犬随机分成两组 ,分别服用受试制剂和参比制剂 ,采用RP HPLC法测定血浆和肠道中药物浓度。结果　受试制剂和参比制剂的Tmax分别为 (6 3±1 2 )h和 (2 4± 1 1)h ,Cmax分别为 (46 2 3± 8 93 )mg·L-1和 (5 8 0 8± 14 65 )mg·L-1,用梯形法计算所得的AUC0 -t分别为 (42 3 2 1± 93 0 8)mg·h·L-1和 (45 8 2 2±112 0 7)mg·h·L-1。与参比制剂相比 ,受试制剂的相对生物利用度为 92 9%± 6 6%。家犬服用替硝唑结肠定位肠溶片 6 5h后结肠中替硝唑的量较多 ,而小肠中则几乎未检测到替硝唑。结论　家犬服用替硝唑结肠定位肠溶片后药物吸收出现明显的滞后 ,替硝唑结肠定位肠溶片在胃和小肠中稳定 ,几乎不释放出药物 ,而在结肠处释放出大量药物 ,具有良好的结肠定位释放效果     

盐酸二甲双胍肠溶片的人体相对生物利用度

目的 :研究盐酸二甲双胍肠溶片在健康男性志愿者体内的相对生物利用度。方法 :2 0名健康志愿者交叉口服盐酸二甲双胍肠溶片和盐酸二甲双胍肠溶胶囊 ,采用HPLC法测定人血清中盐酸二甲双胍的浓度 ,使用NDST程序对各药动学参数进行方差分析和双单侧t检验。结果 :口服 10 0 0mg盐酸二甲双胍肠溶片和盐酸二甲双胍肠溶胶囊的cmax分别为 :(2 .6 1±0 .85 ) ,(2 .4 1± 0 .84 )mg L-1;tmax分别为 :(3.13± 0 .78) ,(3.4 8± 0 .95 )h ;T1/2 分别为 :(3.80± 0 .99) ,(3.2 9± 0 .5 4 )h ;AUC0→ 16分别为 :(13.95± 3.97) ,(12 .76± 4 .0 2 )mg·h·L-1;AUC0→∞ 分别为 :(14 .78± 3.97) ,(13.4 2± 4 .18)mg·h·L-1。统计学处理结果 ,两剂型的药动学参数间均无显著性差异 ,受试制剂的相对生物利用度为 (113.8± 2 5 9) %。结论 :2种制剂具有生物等效性     

替硝唑片的相对生物利用度及其生物等效性评价

目的研究替硝唑片在健康人体内的药代动力学及相对生物利用度。方法以 18名健康志愿者为试验对象 ,采用同体交叉试验方法 ,单剂量口服 1 0 g替硝唑片后 ,用高效液相色谱法测定血浆中药物浓度。结果达峰时间分别为 (1 72± 0 4 6 )h和 (1 6 7± 0 77)h ;达峰质量浓度分别为(18 4 2± 1 15 )mg·L-1和 (16 5 2± 1 81)mg·L-1;消除半衰期分别为 (11 92± 1 6 8)h和(13 0 2± 1 92 )h ;药时曲线下面积 (AUC0→ 60 )分别为 (32 1 2 4± 2 4 39)mg·h·L-1和 (32 9 33±32 12 )mg·h·L-1。结论被试制剂与对照制剂两种制剂生物等效。     

高效液相色谱法测定盐酸二甲双胍肠溶片在正常人体的药动学及生物利用度

目的 :研究盐酸二甲双胍肠溶片与普通片的药动学和生物利用度。方法 :受试者交叉口服单剂量 ( 10 0 0mg)肠溶片与普通片 ,用反相高效液相色谱法测定血药浓度。结果 :两种片剂的主要药动学参数分别为Cmax( 2 .9± 0 .7)mg·L- 1和 ( 2 .6±0 .6)mg·L- 1,Tmax为 ( 2 .6± 0 .4)和 ( 2 .3± 0 .5)h ,T1 2Ka为 ( 0 .87± 0 .2 6 )h和 ( 0 .81± 0 .2 3 )h ,T1 2Ke为 ( 1.6± 0 .4)h和 ( 1.9±0 .6)h ,AUC为 ( 12 .2± 1.1)mg·L- 1·h- 1和 ( 11.9± 1.2 )mg·L- 1·h- 1。肠溶片相对于普通片的生物利用度F为 ( 10 3 .0±12 .0 ) %。结论 :两种剂型的各药动学参数之间差异均无显著性 (P >0 .0 5) ,经双向单侧t检验 ,两制剂具有生物等效性。     

醋氯芬酸肠溶片在健康男性志愿者体内的药代动力学及生物等效性研究

目的 :研究国产醋氯芬酸肠溶片在健康志愿者体内的药代动力学参数和生物等效性。方法 :2 0名健康男性志愿者随机交叉口服国产醋氯芬酸肠溶片 1 0 0mg和进口醋氯芬酸片 1 0 0mg,采用HPLC法测定给药后不同时间点的血浆醋氯芬酸浓度。用3p97程序计算其药代动力学参数 ,评价两种制剂的生物等效性和生物利用度。AUC0 - 2 4 ,AUC0 -inf和Cmax经方差分析和双单侧t检验。结果 :试验药和参比药的醋氯芬酸Cmax分别为 2 0±5mg·L- 1 和 2 0±6mg·L- 1 ;Tmax分别为 2 .7± 0 .5h和 2 .0±0 .5h;AUC0 - 2 4 分别为 5 5±2 6mg·h- 1 ·L- 1 和 5 2± 2 1mg·h- 1 ·L- 1 。试验药与参比药AUC0 - 2 4 之比和Cmax之比的 90 %可信区间分别为 92 .2 %～ 1 2 0 .7%和 91 .8%～ 1 1 8.9%。试验药的人体相对生物利用度为 1 1 2 %± 42 %。结论 :两种制剂的主要药代动力学参数均无显著性差异 ,具有生物等效性。试验药的生物利用度符合要求。     

替诺昔康片人体生物等效性研究

目的　以Mobiflex片为参比药物 ,研究替诺昔康片的人体药代动力学和相对生物利用度 ,以判断两种制剂是否具有生物等效性。方法　 2 4名健康志愿者随机分组交叉自身对照给药 ,每次服药后 2 4 0h内多点采血 ,HPLC法测定血清中药物浓度。结果　两制剂的血药浓度经时变化基本一致 ,替诺昔康片和Mobiflex片的主要药代动力学参数分别为 :T1/2Ke(6 9 6 8± 12 5 6 )h ,(6 8 75± 13 39)h ;Cmax(2 95±0 5 0 )mg·L-1,(2 82± 0 4 8)mg·L-1;AUC0～t(2 0 9 70±32 4 3)mg·L-1·h-1,(2 0 0 6 5± 18 5 7)mg·L-1·h-1;AUC0～∞(2 2 8 4 5± 36 0 7)mg·L-1 h-1,(2 18 11± 2 1 34)mg·L-1·h-1;Tmax(2 75± 1 0 7)h ,(2 75± 1 11)h ,经配对t检验差异均无显著性。替诺昔康片相对生物利用度为10 5 0 6 %± 16 6 1% (99 2 5 %～ 110 87% )。结论　替诺昔康片与Mobiflex片具有生物等效性     

替硝唑片在健康人体的药代动力学和相对生物利用度

目的研究替硝唑片在健康人体的药代动力学和相对生物利用度。方法采用高效液相色谱法测定20名健康男性志愿者,随机交叉单剂量口服替硝唑片1g后血浆中的药物浓度,计算药代动力学参数和相对生物利用度,并进行生物等效性评价。结果受试和参比替硝唑片的t1/2分别为(13.98±1.55)h、(13.80±0.93)h,tmax分别为(2.1±1.0)h、(2.3±0.9)h,cmax分别为(18.60±2.27)mg·L-1、(18.47±3.14)mg·L-1,AUC0τ分别为(368.49±44.08)mg·L-1·h-1、(353.86±40.99)mg·L-1·h-1。受试制剂于参比制剂的人体相对生物利用度为104.9±13.4%。结论两种制剂的药代动力学参数相近,具有生物等效性。     

HPLC测定替硝唑结肠定位肠溶片含量和有关物质检查

目的:建立高效液相色谱法测定替硝唑结肠定位肠溶片中替硝唑含量和有关物质含量。方法:采用ODS柱(4.6 mm×25 cm,10μm),流动相甲醇-水(20:80),流速0.9 mL·min-1,检测波长317 nm,进样量20μL。结果:回归方程为Y=3.987×106X+9.441×104(r=0.9999),线性范围0.025-0.4 mg·mL-1。含量测定回收率为(100.7±0.22)％,(101.8±0.20)％,(101.0±0.05)％。最小检测量为2 ng。结论:此法可用于替硝唑结肠定位肠溶片的有关物质检查和含量测定。     

缬沙坦3种制剂的健康人体生物等效性研究

目的 :研究缬沙坦 3种制剂的人体生物利用度和药动学特征。方法 :2 4名健康男性受试者采用三制剂三周期随机交叉试验设计 ,分别口服单剂量 80mg缬沙坦片剂 (被试制剂T 1)、胶囊 (被试制剂T 2 )和缬沙坦胶囊 (参比制剂R)。采用HPLC 荧光检测法测定血浆样品中的缬沙坦浓度。结果 :T 1,T 2与R的主要药动学参数分别为 :Tmax(2 .4±s 0 .8)h ,(2 .8± 0 .8)h和 (2 .2± 0 .5 )h ;Cmax(2 .2± 0 .8)mg·L- 1,(1.9± 1.0 )mg·L- 1和 (2 .0± 1.0 )mg·L- 1;AUC0 2 4 (12± 4 )mg·h·L- 1,(11± 4 )mg·h·L- 1和 (11± 5 )mg·h·L- 1;T12 β(6 .0± 1.1)h ,(5 .8± 1.0 )h和 (5 .9± 0 .9)h。相对生物利用度 :(117± 37) % (T 1)和 (10 4± 4 4) % (T 2 )。药动学参数经多因素方差分析显示周期间与制剂间差异均无显著意义 (P >0 .0 5 ) ,双单侧t检验表明接受T 1与R和T 2与R生物等效的假设 ,经计算 90 %置信区间均在规定值内。结论 :T 1,T 2与R 3种制剂生物等效     

苦参素软胶囊的人体药代动力学研究

目的　研究健康人口服苦参素软胶囊后的药代动力学。方法　用高效液相色谱法测定 18名男性健康志愿者口服苦参素软胶囊后的经时血药浓度 ;用3p97软件计算有关药代动力学参数。结果　该制剂的 t1/2 、Tmax、Cmax、AUC0～ 6分别为 (2 .4 8± 0 .86 ) h,(1.6 9± 0 .6 9) h,(0 .79± 0 .31) mg· L-1和 (2 .4 1±0 .71) mg·L-1·h-1。结论　提供了苦参素软胶囊在健康人体的药动学数据 ,可为临床用药提供参考。     

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.