Toxicological properties of surfactants

Surfactants are of considerable importance in the field of detergents and in cosmetics. Of the anionic, nonionic, and cationic surfactants the most important products — as far as sales volume is concerned — belong to the anionic type. Anionic and nonionic surfactants taken orally are of low toxicity according to acute toxicity tests as well as long term studies, while certain cationics are moderately toxic. In local application, compatibility with skin and mucous membranes is strongly dependent on concentration. Surfactant action on biological systems can largely be explained on the basis of physico-chemical properties of the surfactants. Some surfactants show pharmacological activity.     

Effects of Guanosine on the Pharmacokinetics of Acriflavine in Rats Following the Administration of a 1:1 Mixture of Acriflavine and Guanosine,a Potential Antitumor Agent

Preclinical studies are currently underway to examine the potential antitumor effects of a 1:1 mixture of acriflavine (ACF; CAS 8063-24-9) and guanosine. Guanosine potentiates the anticancer activity of some compounds. However, the effects of guanosine on the pharmacokinetics of ACF in mammals are unknown. Therefore, this study investigated the effects of guanosine on the pharmacokinetics of ACF after administering a 1:1 mixture of ACF and guanosine in rats. The rats were given either 10 mg/kg of the mixture or 5 mg/kg ACF via an intravenous bolus injection; or 30 mg/kg of the mixture or 15 mg/kg ACF intramuscularly. An HPLC-based method, which was validated in this laboratory, was used to analyze the levels of trypaflavine (TRF) and proflavine (PRF) in the plasma, bile, urine, and tissue homogenates. It was found that TRF and PRF were rapidly cleared from the blood and transferred to the tissues after the i.v. bolus or i.m. injection of the combination mixture. Both TRF and PRF were found to be most highly concentrated in the kidneys after the i.v. bolus or i.m. injection, followed by slow excretion to the bile or urine. Guanosine had no effect on the plasma disappearance of TRF or PRF after the i.v. bolus injection. However, guanosine led to a prolongation of the plasma levels of PRF after the i.m. administration of the combination mixture, resulting in a 2 fold increase in the bioavailability (BA) of PRF The concentrations of TRF and PRF in all the tissues examined were similar in the groups given the mixture and ACF. However, guanosine led to a prolongation of the biliary and urinary excretions of both TRF and PRF after the i.v. bolus (1.25 fold) or i.m. (1.5-2.4 folds) injection. These prolonged effects of guanosine on the plasma disappearance or urinary excretion of TRF and PRF might be one reason for the enhanced antitumor effects of ACF. However, more study will be needed to further examine this potential mechanism.     

Tissue distribution metabolism and excretion of 2,2′,4,4′, 5-pentachlorodiphenyl ether in the rat

The tissue distribution, metabolism and excretion of ¹⁴C-2,2,4,4,5-pentachlorodiphenyl ether (PCDE) were studied in the rat. Radioactivity was distributed in all tissues examined, with the highest concentrations being found in the fat followed by the skin, liver, kidney and muscle. Most of the radioactivity found in the tissues was due to unchanged PCDE. Decay of PCDE in the blood was fitted to a four-compartment pharmacokinetic model, and the last compartment had a half-life of 5.8 days. A total of 55% and 1.3% of an orally administered dose was excreted in feces and urine, respectively, in 7 days. More than 64% of the fecal radioactivity was due to unchanged PCDE, while hydroxylated PCDE accounted for 23%.     

甲磺酸左氧氟沙星的药代动力学研究

用微生物法测定了ＭＳＡＬＶＬＸ在狗体内的药代动力学过程符合二室模型。４、８和１６ｍｇ／ｋｇ口服给药的Ｃｍａｘ分别为１．７３、２．８９和８．２８ｍｇ／Ｌ,ＡＵＣ值分别为１５．４３、３１．９５和７０．２ｍｇｈ／Ｌ,ＭＲＴ分别为６．９６、７．５８和６６２８ｈ。大鼠口服２０ｍｇ／ｋｇ的Ｃｍａｘ为２．８６ｍｇ／Ｌ,ｔ１／２β为２．２ｈ,ＡＵＣ为７．４ｍｇｈ／Ｌ,ＭＲＴ为３ｈ。大鼠口服后７２ｈ的尿中排泄率为４２％,而７２ｈ胆汁排泄率为３８．２％。     

银杏叶注射液对早期糖尿病肾病尿微量白蛋白的影响

目的:探讨银杏叶注射液对早期糖尿病肾病尿微量白蛋白排泄率的影响。方法:选择早期糖尿病肾病患者84例,随机平均分为2组,对照组给予常规治疗,治疗组在对照组的基础上加用银杏叶注射液10mL,静脉滴注,1次.d-1,连续3wk。比较2组在治疗前后尿微量白蛋白及相关临床、生化指标的变化情况。结果:与对照组比较,治疗组尿微量白蛋白排泄率显著降低(P<0.05)。结论:银杏叶注射液对早期糖尿病肾病具有治疗作用。     

Pharmacokinetics,tissue distribution and excretion of porcine fibrinogen after intraperitoneal injection of a porcine-derived fibrin glue to rats

The aim of the present study was to characterize the preclinical pharmacokinetics, tissue distribution and excretion profiles of porcine fibrinogen in rats after intraperitoneal injection of a porcine-derived fibrin glue. A sensitive and rapid isotope-labeled assay method was developed and validated for quantitative analysis in biological analysis. Porcine fibrinogen, the major composition of the fibrin glue, was radioiodinated with Na¹²⁵I using the Iodo-Gen method. Following the purification and identification of ¹²⁵I-porcine fibrinogen, the fibrin glue containing ¹²⁵I-porcine fibrinogen was intraperitoneally administered to rats at three single dosages (100, 200, 400 mg/kg of porcine fibrinogen). The results showed that the ¹²⁵I-labeled assay method was suitable for the quantification of porcine fibrinogen in plasma samples, tissue samples and excreta samples with satisfactory linear (r² > 0.998), precision (<13%), accuracy (95.9–104.2%) and recovery (>85%). After three single administrations, plasma concentration profiles showed a slow absorption phase with the mean t_max of 1.83–5.67 h and a slow elimination proceeding with the terminal elimination half-life (T_1/2) of 84.5–96.3 h. Porcine fibrinogen was widely distributed to most of the tissues examined after a single intraperitoneal administration at 200 mg/kg to rats. The radioactive porcine fibrinogen showed substantial disposition in liver, kidneys, stomach and intestine. Approximately 79.3% and 17.2% of administered radioactivity were recovered in urine and feces within 528 h post-dosing, which indicated the major elimination route was urinary excretion.     

The melamine excretion effect of the electrolyzed reduced water in melamine-fed mice

Our hypothesis is that the intake of functional water, electrolyzed reduced water (ERW) can excrete melamine in body was evoked by melamine-tainted feed (MTF). To address this issue, we investigated the effect of ERW in MTF-mice model by way of body weight gain, incidence of urinary crystals and bladder stone, biochemical and haematological examination, histopathologic finding of kidney and urinary bladder, and the evaluation of bladder stone.We found that the rate of body weight gain was significantly more increased in MTF + ERW group than MTF + PW group. Accordingly, the number of immunocytes such as leukocyte, neutrophil and monocyte as well as the mean weight of spleen was significantly increased in MTF + ERW group. The incidence of urinary crystals was significantly higher in MTF + ERW group, whereas the incidence of urinary bladder stones was lower in MTF + ERW group (52.4%) than in MTF + PW group (38.1%). Also, urinary crystals were more precipitated in MTF + ERW group than MTF + PW group, and urinary bladder stone consists of 100% melamine. Collectively, our data clearly show that ERW intake is helpful to excrete of melamine in MTF mice model and this is the first report on the melamine excretion and clinically implying the safer fluid remedy for melamine-intoxicated hosts.     

羟基红花黄色素A脂质载体及水溶液在大鼠体内的代谢、排泄、生物利用度研究

目的：研究不同的羟基红花黄色素A（HSYA）剂型对HSYA代谢、排泄、生物利用度的影响。方法：大鼠灌胃给予HSYA脂质制剂和水溶液,采用HPLC及LC-MS检测血浆、胆汁、粪便、尿液样品。结果：大鼠灌胃给予HSYA脂质制剂和水溶液后,在大鼠胆汁中均发现HSYA及其II相代谢产物;HSYA原药的质荷比为611,而两个II相代谢产物的质荷比分别为918和691,结合酶降解实验表明这两个代谢产物分别为HSYA的谷胱甘肽结合物和硫酸酯结合物。但是同水溶液相比,HSYA脂质制剂显著性降低了HSYA及其II相代谢产物从胆汁的排泄量。大鼠灌胃给予HSYA脂质制剂后,HSYA原药从胆汁、粪便、尿液中24h的累积排泄量分别为（0.05±0.03）%、（8.80±2.30）%、（37.99±17.50）%,其cmax、AUC0-8h分别为2.79μg·mL^-1、402.51μg·min·mL^-1;而大鼠灌胃给予HSYA水溶液后,HSYA原药从胆汁、粪便、尿液中24h的累积排泄量分别为（0.32±0.22）%、（44.66±8.00）%、（5.58±1.30）%,其cmax、AUC0-8h分别为0.08μg·mL^-1、10.73μg·min·mL^-1。结论：实验结果表明脂质制剂可能不会改变HSYA的代谢机制,但是显著性降低了HSYA从粪便和胆汁的排泄量,提高了其生物利用度。     

Detection and determination of anabolic steroids in nutritional supplements

A method is described for the determination of anabolic steroids including testosterone, 19-nor-4-androstene-3,17-dione, 4-androstene-3,17-dione and nandrolone in food supplements. Initial clean-up is done by HPLC followed by determination with GC/MS. A ‘contaminated’ food supplement was analysed and appeared to contain 19-nor-4-androstene-3,17-dione and 4-androstene-3,17-dione. One capsule of this nutritional supplement was ingested by five male volunteers. Urine samples were collected and analysed by GC/MS and GC/MS-MS. Neither the ratio testosterone/epitestosterone, nor the ratio androstenedione/epitestosterone increased significantly. Concentrations above 2 ng/ml for norandrosterone, the major metabolite of nandrolone, were detected until 48–144 h after ingestion of the food supplement.     

Plasma pharmacokinetics,tissue distribution and excretion study of 6-gingerol in rat by liquid chromatography–electrospray ionization time-of-flight mass spectrometry

A rapid resolution liquid chromatography coupled with electrospray ionization (ESI) time-of-flight mass spectrometry method was developed and validated for quantitative analysis of 6-gingerol in plasma and various tissues. Liquid–liquid extraction was employed as sample preparation technique. Biological samples were separated on an Agilent Zorbax StableBond-C₁₈ column (4.6 mm × 50 mm, 1.8 μm) and detected by TOF/MS with electrospray ionization (ESI) interface in positive ion mode. Calibration curves (1/x² weighted) offered satisfactory linearity (r² > 0.995) within the test range. The lower limit of quantification in different matrices was in a range of 10–100 ng/mL. Inter- and intra-day precision were in the range of 0.91–11.90% and 0.75–10.23%, respectively. Recoveries in plasma, urine and tissues ranged from 72.5% to 90.4%. Glucuronide of 6-gingerol, the major metabolite of 6-gingerol, was further determined after β-glucuronidase hydrolyzation. This developed method was successfully applied to pharmacokinetics, tissue distribution and excretion studies of 6-gingerol after oral or intraperitoneal administration in rats.