高效液相色谱法测定血中伊立替康及活性代谢物SN-38浓度

目的：建立高效液相色谱法同时测定结直肠癌患者血中的伊立替康（CPT-11）及其活性代谢物7-乙基-10-羟基喜树碱（SN-38）的浓度,并对我院基因型指导给药方案进行评价。方法：以2μg·mL-110-羟基喜树碱作为内标,先用100μL 10%高氯酸沉淀蛋白,再用50μL 10%高氯酸酸化血浆。采用Agilent ZORBAX Eclipse C8色谱柱（4.6 mm×150 mm,5μm）对CPT-11和SN-38进行分离;以0.05 mol·L-1的磷酸二氢钠-乙腈-三乙胺（75∶25∶0.1,v∶v,磷酸调pH 3.0）为流动相;荧光检测波长：激发波长380 nm,发射波长550 nm。结果：人血浆中CPT-11和SN-38线性范围均为3~1000 ng·mL-1,定量下限为3 ng·mL-1;准确度分别是98.5%和100.0%;回收率分别是83.8%和84.3%。结论：本方法可靠、简便、快速,可为伊立替康个体化给药提供参考。     

HPLC-荧光法测定人血浆中伊立替康及其活性代谢产物的浓度

目的:建立同时测定人血浆中伊立替康(CPT-11)及其活性代谢产物7-乙基-10-羟基喜树碱(SN-38)浓度的方法。方法:血浆样品经乙腈沉淀蛋白及盐酸酸化后,以喜树碱为内标,采用高效液相色谱-荧光法测定。色谱柱为Waters Luna C_(18),流动相为0.05 mol/L磷酸二氢钠溶液-乙腈(70∶30,V/V,用磷酸调节pH至4.0),流速为1 mL/min,激发波长为380 nm,发射波长为480 nm(CPT-11)、535 nm(SN-38),柱温为25℃,进样量为20μL。结果:CPT-11和SN-38血药浓度分别在200~1 000、5~45 ng/mL范围内线性关系良好(r分别为0.999 4、0.999 2,n=5),定量下限分别为200、5 ng/mL;日内、日间RSD为1.68%~5.57%;CPT-11和SN-38的相对回收率分别为90.12%~106.93%(RSD<8%,n=5)、92.07%~102.56%(RSD<6%,n=5),提取回收率分别为72.23%~86.56%(RSD<6%,n=5)、71.98%~83.44%(RSD<7%,n=5)。采用该方法测得5例结肠癌患者体内CPT-11和SN-38的血药浓度分别为431.13~617.19、13.97~31.89 ng/mL(静脉滴注结束后1 h),398.14~584.43、11.61~29.94 ng/mL(静脉滴注结束后2 h)。结论:该方法样品处理简单、快速,且灵敏度高、重复性好,适用于临床常规监测CPT-11及其代谢物SN-38的血药浓度及药动学研究。     

伊立替康及其主要活性代谢产物在人血浆和唾液中的药物浓度及药动学

目的:测定伊立替康(CPT-11)及其主要活性代谢物SN-38和SN-38G在人血浆和唾液中的浓度,研究伊立替康及其主要活性代谢物在2种体液中药动学参数的差异。方法:6例采用Folfiri两周方案治疗的晚期结肠癌患者,给药剂量180 mg.m-2,测定血浆和唾液中药物浓度,计算药动学参数。样品先经甲醇-乙腈(50∶50)沉淀蛋白,用盐酸酸化使内酯环开环,再定量。采用Waters Platform ZMD4000液相色谱仪,Xterra RP18柱,波长为370 nm,检测波长为470 nm和534 nm。喜树碱作内标。结果:血浆和唾液CPT-11及其活性代谢物,酸性提取物在此条件下的稳定性较好。3种待测物线性范围皆为1～1 000 ng.mL-1,检测限都是1 ng.mL-1。RSD为3.1%～11.7%,测定回收率为93.2%～109.8%,中位提取回收率为91%。CPT-11在2种体液中AUC相近,药动学参数相近;SN-38唾液中的AUC约为血浆的42%;SN-38G在唾液中未检出。结论:建立的方法可用于测定CPT-11,SN-38和SN-38G在人血浆和唾液中的药物浓度,可满足临床进行CPT-11及其主要活性代谢物人体药代动力学研究。在血浆样品不易得时,可采集唾液样品,两者药动学参数具有一定的相关性。     

伊立替康及其主要活性代谢物血药浓度和药代动力学测定

目的 测定抗癌药物伊立替康(CPT-11)及其主要活性代谢物SN-38,SN-38G的血药浓度和药代动力学指标.方法 样品先经甲醇-乙腈(50 ∶ 50体积比)沉淀蛋白,并用盐酸酸化使内酯环开环.用高效液相色谱仪定量:以喜树碱作内标;Xterra RP18柱,激发波长370 nm,检测波长为470 nm和534 nm.结果 血浆CPT-11及其活性代谢物、酸性提取物在此条件下的稳定性较好.三种待测物线性范围皆为1～1000 ng/ml,检测限都是1 ng/ml.相对标准差为3.1％～11.7％的血浆.测定回收率为93.2％～109.8％.中位提取回收率为91％.结论 所建立的方法可用于测定CPT-11,SN38和SN38-G在人血浆中的药物浓度,可满足临床进行CPT-11人体药代动力学研究.     

人血浆中伊立替康及其活性代谢物7-乙基-10羟基喜树碱浓度高效液相色谱-荧光测定方法的建立

目的:建立人血浆中伊立替康(CPT-11)及其代谢物7-乙基-10羟基喜树碱(SN-38)的浓度测定方法并进行方法学考证。方法:用Luna 5u CN100A(4.6 mm×150 mm,5μm)色谱柱,乙腈与醋酸铵缓冲溶液(50 mmol.L-1,pH4)为流动相梯度洗脱,CPT-11的检测波长为Ex/Em=368 nm/432 nm,SN-38的检测波长为Ex/Em=368 nm/535 nm。结果:CPT-11保留时间为(9.3±0.3)min,SN-38保留时间为(4.8±0.3)min。空白样品在CPT-11、SN-38及内标喜树碱出峰位置均无干扰。CPT-11在46.9～6 000.0nmol.L-1的范围内线性良好,SN-38在2.0～250.0nmol.L-1的范围内线性良好,r值均为0.998。低浓度点RSD均在20%内,其余浓度点的RSD均在15%内,准确度均在85%～115%之间。血浆样品长期冻存稳定性良好,反复冻融3次及提取后室温放置24 h条件下,样品浓度均无显著变化。结论:使用高效液相色谱-荧光检测方法简便,准确,灵敏,适用于伊立替康及其活性代谢物SN-38的血药浓度检测。     

HPLC法测定血浆中伊立替康及其代谢产物SN-38、SN-38G浓度及方法学研究

目的：建立同时测定晚期结直肠癌患者血浆中伊立替康（CPT-11）及其活性代谢产物7-乙基-10-羟基喜树碱（SN-38）和非活性代谢产物的SN-38葡萄糖醛酸化（SN-38G）的浓度测定方法,并进行方法学验证。方法：以Kromacil C₁₈为色谱柱,甲醇-水（含5 mmol·L^-1 KH₂PO₃,pH=3.0）=55∶45为流动相,激发波长λ_ex=385 nm、发射波长λ_em=535 nm。结果：CPT-11在20~5000 ng·mL^-1范围内线性良好,SN-38在2~500 ng·mL^-1范围内线性良好,r值均为0.999。CPT-11和SN-38的提取回收率分别为53.26%~59.86%和66.83%~71.30%。CPT-11低、中、高三种浓度的日间和日内精密度均小于6.32%;SN-38低、中、高三种浓度的日间和日内精密度均小于7.02%。血浆样品反复冻融3次、室温放置8 h、进样器中放置24 h及长期冻融,稳定性均良好,样品浓度均未见显著改变。结论：使用高效液相色谱-荧光定量检测法简便、准确、灵敏,适用于晚期结直肠癌患者血浆中伊立替康及其代谢产物SN-38、SN-38G的血药浓度测定。     

HPLC-FLD测定大鼠血浆中的10-羟基喜树碱方法学研究

目的 建立一种简单、准确的测定大鼠血浆中10-羟基喜树碱含量的高效液相色谱-荧光检测法(HPLC-FLD).方法 用1%冰醋酸-甲醇溶液处理血浆样品,采用高效液相色谱-荧光检测器,以喜树碱为内标.色谱柱:Phenomenex Luna C18(4.6 mm×250 mm,5μm),流动相:以5%乙腈为流动相A,乙腈为流动相B,流速为1.2 mL·min-1,荧光检测器激发波长和发射波长分别为Ex=380 nm,Em=515 nm.采用室温梯度洗脱,进样体积为50μL.结果 本试验采用两条分段函数,大鼠血浆中10-羟基喜树碱在1.25~20 ng·mL-1及20~320 ng·mL-1范围内线性良好,线回归系数分别为0.9998和0.9995.方法 准确度为98.9%~103.8%,10-羟基喜树碱高、中、低3个浓度的提取回收率均大于80%.日内精密度RSD<4.2%,日间精密度RSD<4.8%.结论 该方法 操作简便,灵敏度高,精密度和准确度好,适用于大鼠血浆中10-羟基喜树碱含量的测定.     

高效液相-荧光检测法测定兔血浆中羟基喜树碱的含量

目的建立高效液相-荧光检测法测定兔血浆中羟基喜树碱含量的方法学。方法色谱柱为D iscovery C18(15cm×4.6mm,5μm),流动相为柠檬酸缓冲液-乙腈-75nm o.lL-1-磷酸二氢钾(70∶23∶7),75nm o.lL-1磷酸二氢钾中含1%三乙胺。流速为1.0m.lm in-1,柱温为40℃,荧光检测波长为λex363nm和λem 530nm。结果该方法的线性范围为13.7656~1957.4468ng.mL-1(r=0.9993)。提取回收率和方法回收率分别为80.90%~103.59%,102.72%~108.16%.日内RSD 7.49%,日间RSD 9.40%。最低检测限为5.2ng.mL-1。结论该方法专属性强,重现性好,操作简便,适用于羟基喜树碱的药代动力学研究和血药浓度监测。     

高效液相-荧光检测法测定羟基喜树碱血浓度

目的:建立高效液相-荧光检测法测定人血浆羟基喜树碱的血浓度.方法:色谱柱为DiscoveryC18(15cm×4.6mm,5μm),流动相为枸橼酸缓冲液-乙腈-75nmol·ml-1磷酸二氢钾(70∶23∶7,含0.1%三乙胺),流速为1.0ml*min-1,柱温为50℃,荧光检测波长为λex363nm和λem530nm.结果:该方法的线性范围为19.3～1957.4ng*ml-1(r=0.9995).最低检测限为5.2ng*ml-1,平均加样回收率为91.8%.结论:该方法专属性强,重现性好,操作简便,适用于羟基喜树碱的药代动力学研究和血药浓度监测.     

HPLC法测定兔血浆中羟基喜树碱浓度

建立测定兔血浆中羟基喜树碱浓度的高效液相色谱-紫外检测法.色谱柱:Lichrospher C18柱(250mm×4.6mm,5μm),C18预柱(10mm×4.6mm,5μm);流动相:乙腈-0.075mol·L-1醋酸铵缓冲液(pH6.4)(30:70),含5mmol的三乙胺;流速:1.0ml·min-1;检测波长:384nm.羟基喜树碱保留时间为5.0min,线性范围为40～1600ng·ml-1,最低检测限为25ng·ml-1.血浆中羟基喜树碱的回收率为96.32%～106.1%.本法简便实用,定量准确,可用于羟基喜树碱药代动力学研究.     

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.     

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.