电感耦合等离子体质-谱法测定人血浆中铋的浓度

目的 建立电感耦合等离子体质谱(ICP-MS)法测定人血浆中铋的浓度.方法 血浆样品经硝酸硝化处理后,用ICP-MS进行检测,检测元素:Bi、Ti(内标),RF功率:1 550 W,等离子体气流速:15 L· min-1,反应气模式:关,样本深度:7.5 mm,雾化室温度:2℃.结果 血浆中铋在0.312～20 ng·mL-1线性关系良好(r=0.999 8),最低定量限为0.312 ng·mL-1,绝对回收率为92.7％～97.5％,日内及日间精密度RSD均＜6.2％.健康志愿者单次给予复方雷尼替丁胶囊2粒(含铋220mg)后铋吸收迅速,平均峰浓度均＜50 ng·mL-1.结论 硝酸硝化前处理及ICP-MS测定人血浆中铋的方法灵敏、准确、简便,能满足生物样品分析的要求,可用于铋体内过程研究.     

口服蒙脱石散对诺氟沙星吸收和疗效的影响

目的:探讨蒙脱石吸附作用对诺氟沙星吸收和疗效的影响.方法:采用紫外分光光度法测定,并做了吸附于蒙脱石的诺氟沙星对大肠杆菌的抑菌实验.结果:蒙脱石对诺氟沙星有强烈的吸附,可用Langmuir吸附等温方程式表征其在人工胃液中的吸附特性,饱和吸附量达 234.7 mg·g -1 .被吸附的诺氟沙星在人工肠液6 h的脱附量仅为吸附量的( 2.1 ± 0.4 )% (n=6).吸附于蒙脱石的诺氟沙星抑菌力为同浓度诺氟沙星的(58±9)%(n=6).结论:蒙脱石吸附作用影响诺氟沙星在体内的吸收.欲达到有效血药浓度发挥治疗作用时,两者应避免同服.若用于治疗胃肠道的各种感染,两者配伍具有协同作用.     

对复方制剂中次硝酸铋、朱砂的金属离子准确分析

中成药陈香露白露片含有次硝酸铋,它是一复合制剂,由陈皮、川木香、大黄等九味药物制成,具有健胃和中、理气止痛功能。次硝酸铋主要起收敛作用。根据卫生部标准(WS3—B—1553—93)是用络合法测定铋离子的含量。标准如下:     

淀粉微球对乳酸环丙沙星的载药特性和吸附机理研究

目的研究淀粉微球对乳酸环丙沙星的载药性能和吸附机理。方法采用反相乳液聚合法制备空白淀粉微球,以乳酸环丙沙星作为模型药物,吸附载药法考察淀粉微球的载药性能,紫外可见分光光度法测定其载药量及包封率,并考察吸附时间、投药量对载药量的影响,同时对淀粉微球的吸附机理进行了探索,测定了热力学参数。结果反相乳液聚合法制备的空白淀粉微球对乳酸环丙沙星的载药量大于100mg·g^-1,包封率可达60%,吸附等温式符合Freundlich公式,可描述为Q=20.36Ce1.73,吸附过程中焓变等于-18.82 kJ·moL^-1,熵变等于-22.65J/mol·K^-1,结论淀粉微球可作为乳酸环丙沙星的载体,对乳酸环丙沙星的吸附机理以物理吸附为主。     

安定、芬太尼预防阑尾手术牵拉的体会

硬膜外麻醉下行阑尾切除时所出现的胃区不适，疼痛等牵拉反应是临床麻醉工作常遇到的问题。本组应用安定、芬太尼静脉给予辅助对预防阑尾手术牵拉反应取得满意效果。现报告如下。临床资料：选择50例阑尾切除术病人，男30例，女20例；年龄16～55岁。ASAⅠ～Ⅱ级。50例病人均采用硬膜外麻醉，在麻醉平面满意后，于切皮前3min从静脉推入安定7.5mg，芬太尼0.075mg。在此称之为第一次给药，对于部分病人在探查或切除阑尾时仍诉疼痛不适者，可再次追加安定2.5mg，芬太尼0．025mg。对于第二次加药仍不能缓解者，可第三次给药。药量同第二次，仍为…     

误服大剂量次枸橼酸铋引起的小儿急性肾功能衰竭(附1例报告)

目的报道铋剂中毒引起小儿急性肾功能衰竭(ARF)的病程变化、肾脏病理和治疗经验。方法个案报道结合文献综述,并检测血清、腹透液和尿铋浓度变化及其注射螯合剂的影响。结果 一小儿服>2.4g次枸橼酸铋胶囊后,次日出现大量蛋白尿,随后无尿,经腹膜透析和2次间断血透,第12天尿量缓慢增加,肾功能逐渐恢复。肾脏病理为急性肾小管坏死,肾间质炎症细胞浸润。腹透液和尿铋浓度相似,注射二巯基丙磺酸钠后透析液和尿中铋浓度较用药前增加,分别为8.3mg/L和13.1mg/L和7.3mg/L和12.5mg/L。结论铋中毒引起的小儿ARF一般预后良好,腹膜透析可清除铋,同时注射螯合剂可加速铋排泄。     

蒙脱石、果胶铋、铝碳酸镁对奥美拉唑的体外吸附

目的:考察蒙脱石、果胶铋、铝碳酸镁3种胃肠黏膜保护剂分别对奥美拉唑的体外吸附,为临床合理用药提供依据。方法:模拟人工肠液,将3种胃肠黏膜保护剂分别加入3种剂量的奥美拉唑肠溶片和肠溶胶囊中,用高效液相色谱法,分别测定吸附前后的药物浓度,计算吸附率并采用方差分析检验,了解不同剂型和不同剂量对吸附率的影响。结果:蒙脱石(3 g)、果胶铋(150 mg)、铝碳酸镁(500 mg)对奥美拉唑肠溶片和肠溶胶囊平均吸附率分别是94．94％和86．13％,33．96％和39．14％,12．46％和12．68％。结论:3种药物在体外对奥美拉唑均有吸附,吸附率的大小分别是蒙脱石>果胶铋>铝碳酸镁。建议临床将3种胃肠黏膜保护剂与奥美拉唑尽量分开服用,避免同时服用可能对奥美拉唑疗效有影响。     

对〈乐得胃〉处方的改进及临床疗效观察

胃及十二指肠溃疡、胃炎、神经性消化不良等疾病系常见病,一般多用“乐得胃”,“胃得乐”等药物治疗,“乐得胃”每片含碳酸氢钠200mg,次硝酸铋300mg,碳酸镁400mg,弗朗鼠李皮25mg。而碳酸氢钠1g 仅能中和约120ml 的0.1N 盐酸,却产     

蒙脱石对氯己定吸附特性的实验研究

目的:研究蒙脱石对醋酸氯己定的吸附特性.方法:采用紫外分光光度法测定不同浓度的醋酸氯己定溶液加入一定量蒙脱石后的含量.结果:蒙脱石对醋酸氯己定有强烈的吸附,可用Langmuir吸附等温式表征其吸附特性.饱和吸附量达371.6 mg·g-1.结论:吸附氯己定可使蒙脱石具有杀菌功能.     

次硝酸铋含量测定方法的改进

次硝酸铋是一种药用原料,具有中和胃酸及收敛的作用,用于胃及十二指肠溃疡及腹泻等。次硝酸铋的含量测定,《中华人民共和国卫生部药品标准化学药品及制剂第一册》(1)采用儿茶酚紫指示液为指示剂,用乙二胺四乙酸二钠滴定液(0.05mol/L)滴定。笔者在实际操作中发现,标准中描述的颜色变化现象不明显,终点不易判断。后按照《中国药典》2005年版二部碱式碳酸铋(2)含量测定项下采用二甲酚橙指示液为指示剂,颜色变化明显,终点易判断,并了比对实验,结果较满意。一、仪器与试药AB204-E型电子天平(瑞士Mellter);次硝酸铋(汕头西拢化工厂批号060800604…     

Controlled flocculation of coarse suspensions by colloidally dispersed solids I: Interaction of bismuth subnitrate with bentonite.

Deflocculated suspensions of coarse powders tend to cake as the individual particles settle out and form compact, cohesive sediments. Limited flocculation results in looser sediments because the settled-out flocs incorporate large amounts of the liquid suspending medium. Controlled flocculation of bismuth subnitrate suspensions was achieved by the addition of small amounts of bentonite. The interaction of the coarse, positively charge bismuth subnitrate particles in aqueous suspension with negatively charged, colloidally dispersed bentonite was investigated by measuring electrophoretic mobility, sedimentation volume, and viscosity. Gradual addition of bentonite dispersion to bismuth subnitrate suspensions first reduced the zeta-potential of the bismuth subnitrate particles from +28 mv to zero, then inverted it, and finally caused it to level off at -20 mv for bismuth subnitrate-bentonite weight ratios below 200. Owing to the much greater specific surface area of bentonite, the surface of the bismuth subnitrate lath-shaped crystals was completely covered by 0.5% of its weight in clay platelets. Adhesion was promoted by electrovalences between surface bismuthyl ions and cation-exchange sites of the clay and by secondary valences. The charge neutralization of bismuth subnitrate by bentonite was a heterocoagulation process: the addition of small amounts of the clay flocculated the bismuth subnitrate suspensions and eliminated caking. While the zeta-potential of the bismuth subnitrate particles leveled off when their surface was saturated with bentonite platelets, sedimentation volume and viscosity continued to increase when the clay concentration was increased further while maintaining the bismuth subnitrate concentration constant. The excess, nonadsorbed bentonite formed the characteristic house-of-cards structure, incorporating the bentonite-coated bismuth subnitrate particles as cornerstones.     

Decreased bioavailability of quinidine sulphate due to interactions with adsorbent antacids and antidiarrhoeal mixtures

The in vitro adsorption of quinidine sulphate on some commercial antacid and antidiarrhoeal preparations was assessed; the effect of some of these admixtures on drug absorption in human bioavailability studies was also measured using salivary secretion data. The adsorption of quinidine on Kaopectate (kaolin-pectin suspension) (25.8 mg/g) and magnesium-trisilicate (23.6 mg/g) was greater than that on Simeco tablets (aluminium hydroxide, magnesium carbonate and hydroxide, simethicone) (5.8 mg/g) or bismuth subnitrate (3.3 mg/g). Salivary quinidine concentrations decreased by 54% and the AUT by 58%, compared with control data, during the quinidine-Kaopectate interaction in vivo. This latter finding suggests a need for clinical monitoring of patients taking quinidine concomitantly with this type of adsorbent-antacid-antidiarrhoeal formulation.     

Uptake of bismuth in motor neurons of mice after single oral doses of bismuth compounds

Bismuth, a component of many gastrointestinal medications, is a heavy metal little studied as regards nervous system uptake. We were interested to see if low doses of intragastric bismuth entered the nervous system, and if dietary selenium influenced the amount of bismuth detected. Mice were given 40 to 1200 mg/kg of bismuth subnitrate (BSN), bismuth subsalicylate (BSS), colloidal bismuth subcitrate (CBS), or ranitidine bismuth citrate (RBC) intragastrically. Mice on low- or high-selenium diets were given 4 to 32 mg/kg of bismuth from RBC. One week later, sections of nervous tissue were stained with autometallography to detect bismuth grains (Bi(AMG)). Bismuth was found in neurons with axons outside of the nervous system, in particular motor neurons, and in cells outside the blood-brain barrier. The lowest bismuth dose which resulted in Bi(AMG) in motor neurons was 696 mg/kg from BSN, 57 mg/kg from BSS, 29 mg/kg from CBS, and 26 mg/kg from RBC. No bismuth was seen in motor neurons of mice on the low-selenium diet. Intragastric doses of bismuth therefore enter mouse motor neurons, and the amount detectable varies with dietary selenium.     

Addition of bismuth subnitrate to omeprazole plus amoxycillin improves eradication of Helicobacter pylori

Objective:

To evaluate whether the addition of bismuth subnitrate to a dual oral therapy regimen with omeprazole plus amoxycillin could improve Helico-bacter pylori eradication.

Methods:

Fifty consecutive Helicobacter pylori-positive patients were randomly enrolled to receive either (A) bismuth subnitrate (300 mg q.d.s.), omeprazole (20 mg b.d.) and amoxycillin (500 mg q.d.s.), or (B) omeprazole (20 mg b.d.) and amoxycillin (500 mg q.d.s.). Both groups (n = 25 each) received the medication for 14 days. H. pylori status was reassessed 30 days after completion of the therapy in order to evaluate eradication rates.

Results:

Six patients were lost to follow-up and therefore excluded from the study (three patients from each group). One patient from Group B withdrew from the study because of side-effects. The addition of bismuth subnitrate to omeprazole and amoxycillin significantly improved its efficacy in eradicating H. pylori, with 72% (18/25) eradication in Group A and 52% (13/25) in Group B (P = 0.027). The addition of bismuth subnitrate to dual oral therapy was also capable of improving the healing of peptic ulcers when compared with dual oral therapy alone (100%, 8/8 vs. 58%, 4/7; P = 0.021).

Conclusion:

Our results demonstrate that the addition of bismuth subnitrate to dual oral therapy enhances H. pylori eradication, and improves healing of peptic ulcers.

     

Prediction of the adsorption of diazepam by activated carbon in aqueous media

Adsorption isotherms for the diazepam-activated carbon system in simulated intestinal fluid (SIF), without pancreatin, and in SIF with different percentages of ethanol were determined as were the solubilities of diazepam in SIF and in SIF with different percentages of ethanol. The surface area of the activated carbon was also evaluated. The results from the experimental work provided information on the relationship between adsorption and solubility. An excellent logarithmic relationship was observed between the adsorption affinity and the solubility of diazepam in the ethanol-SIF mixtures. This relationship was explained by a linear relationship between the differential free energy of displacement and the differential free energy of solution. Excellent correlations were also observed between the amounts of diazepam adsorbed by activated carbon and the solubilities of diazepam in the ethanol-SIF mixtures. This relationship was used to predict the complete isotherm, which was in excellent agreement with the experimental work.     

Decreased serum testosterone levels in rats exposed intraperitoneally to bismuth subnitrate

The consumption of bismuth is increasing and knowledge of the potential teratogenic and reproductive damage of bismuth exposure is fragmentary. In the present study we used autometallography (AMG)--the histochemical silver amplification technique--to trace bismuth in the testis and pituitary glands of Wistar rats injected intraperitoneally with bismuth subnitrate. Large amounts of bismuth AMG grains were concentrated in the lysosomes of Leydig cells, and serum testosterone levels were reduced when compared with controls. No histochemical traces of bismuth were found in the anterior lobe of the pituitary gland. Compared with their corresponding controls, neither follicle-stimulating hormone nor luteinizing hormone were affected. The selective uptake of bismuth in Leydig cells, followed by decreased testosterone levels, emphasizes a potential hazard of bismuth-provoked male reproductive impairment.     

Leydig cell death in rats exposed to bismuth subnitrate

In a previous study, rats were treated with one injection of 500 mg kg(-1) bismuth subnitrate intraperitoneally and maintained for 2 weeks. Bismuth was observed in Leydig cells, with a subsequent reduction in serum testosterone levels. In the present study, stereological procedures were used to estimate the number of Leydig cells in the right testis from the retained rats used in the previously published study.The mean number of Leydig cells in the control group was estimated to be 18.7 x 10(6) (coefficient of variation = 0.11), which is comparable to previous estimations. In the group exposed to bismuth the mean was 15.5 x 10(6) (coefficient of variation = 0.18). The observed 17% difference between the two groups was statistically significant (2P = 0.019). The inter-individual variation was largest in the bismuth-exposed group. Testis weight and body weight were not significantly reduced after bismuth exposure. These findings support the hypothesis that bismuth has a direct toxic effect on rat Leydig cells and underscores the potential risks of bismuth on male reproduction.     

Inorganic bismuth(III) compounds in the therapy.

A survey is given of the pharmacopoeial preparations of inorganic Bi(III) compounds: bismuth subnitrate and bismuth subcarbonate. The use of these preparations, methods of preparation, qualitative and quantitative assays have been reviewed.     

Effect of Anions on Adsorption of Bile Salts by Colestipol Hydrochloride

The Langmuir affinity constant and adsorptive capacity for the adsorption of citrate anion or cholate anion by colestipol hydrochloride at pH 7.5, 37°C, were similar. Prior exposure of colestipol hydrochloride to citrate anion caused the adsorption of cholate anion to decrease slightly in comparison to a control utilizing only cholate anion. The concentration of citrate anion was found to be directly related to the decrease in cholate anion adsorption. Simultaneous exposure of colestipol hydrochloride to citrate and cholate anions at pH 7.5, 37°C, resulted in the same adsorption of cholate anion as sequential exposure to citrate anion followed by cholate anion. Sequential exposure of colestipol hydrochloride to simulated gastric fluid and simulated intestinal fluid containing cholate anion resulted in a small decrease in cholate adsorption which was attributed to competition with phosphate anion in simulated intestinal fluid. Pepsin in the simulated gastric fluid did not affect adsorption of cholate anion from simulated intestinal fluid. Preexposure to components of tomato juice and orange juice also slightly reduced the adsorption of cholate anion by colestipol hydrochloride.     

Comparison of one-day oral dosing with three bismuth compounds for the suppression of Helicobacter pylori assessed by the13C-urea breath test

Assessment of intragastric urease activity by the 13C-urea breath test was performed before and after one day of dosing with either De-Noltabs (tripotassium dicitrato bismuthate, one tablet 1 q.d.s.), Pepto-Bismol liquid (bismuth salicylate 30 ml q.d.s.), or Roter tablets (bismuth subnitrate, one tablet q.d.s.) in twelve Helicobacter pylori-positive patient volunteers. There was a significant decrease in the excess of 13CO2 after one day of dosing with each of the three bismuth compounds, but analysis of variance could detect no difference between the effects of the three compounds. Systemic absorption of bismuth following oral dosing with either Pepto-Bismol or Roter is minimal, yet both compounds have a suppressive effect on H. pylori similar to that of De-Noltab. This study suggests that the action of all three bismuth compounds is within the gastric lumen, and that systemic absorption of bismuth is not necessary for activity against H. pylori.