Circular dichroism detection in high-performance liquid chromatography: Evaluation of the anisotropy factor

The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized.     

环糊精在鼻腔给药系统中的应用

综述了环糊精作为鼻腔给药系统赋形剂的应用及安全性.     

妇女叶酸增补中需要关注的问题

妇女围孕期增补叶酸能够有效预防神经管缺陷等疾病的发生。随着对叶酸研究的不断深入，叶酸补充中出现了诸多问题。本文简要综述了叶酸在服用方式以及基础和临床研究中出现的值得讨论、已经引起关注和需要进一步研究探讨的问题，并提出了深入研究叶酸可能的发展趋势。     

食品添加剂KAl（SO4）2中Al的吸收,排泄,蓄积实验研究

目的：探讨我国主要含铝食品添加剂——硫酸铝钾中铝的吸收、排泄和贮留的基本情况。方法：１．采用６月龄日本雄性大耳兔８只进行３天的代谢平衡实验。２．选用２～３月龄２１只雄性兔进行３２周的蓄积实验。结果：代谢实验表明铝的表观吸收率平均在１０％左右，约９０％的口服铝在粪中排出。尿铝随摄入铝的增加而增加，但肾排铝能力不足吸收的１０％。兔的蓄积实验证明在３２周实验后实验兔随铝摄入的增加其主要脏器均有不同程度的铝蓄积。其蓄积量的顺序为：骨＞肝＞肾＞脑＞心（３．８９～１０５．４６ｍｇ／ｋｇ干重）；蓄积增长倍数为：肝＞脑＞肾＞骨＞心（１．５１～４．５８倍）。结论：１．食品添加剂硫酸铝钾中铝的表观吸收率平均在１０％左右。尿铝随摄入铝的增加而增加，但肾排铝量不足吸收的１０％。２．长期大量摄入含铝食品添加剂可导致机体铝蓄积，其中脑、骨、肝、肾蓄积较明显。     

Effects of exposure to air pollution on blood coagulation

BACKGROUND: Consistent evidence has indicated that air pollution increases the risk of cardiovascular diseases. The underlying mechanisms linking air pollutants to increased cardiovascular risk are unclear. OBJECTIVES: We investigated the association between the pollution levels and changes in such global coagulation tests as the prothrombin time (PT) and the activated partial thromboplastin time (APTT) in 1218 normal subjects from the Lombardia Region, Italy. Plasma fibrinogen and naturally occurring anticoagulant proteins were also evaluated. METHODS: Hourly concentrations of particulate (PM10) and gaseous pollutants (CO, NO2, SO2, and O3) were obtained from 53 monitoring sites covering the study area. Generalized additive models were applied to compute standardized regression coefficients controlled for age, gender, body mass index, smoking, alcohol, hormone use, temperature, day of the year, and long-term trends. RESULTS: The PT became shorter with higher ambient air concentrations at the time of the study of PM10 (coefficient = -0.06; P < 0.05), CO (coefficient = -0.11; P < 0.001) and NO2 (coefficient =-0.06; P < 0.05). In the 30 days before blood sampling, the PT was also negatively associated with the average PM(10) (coefficient = -0.08; P < 0.05) and NO2 (coefficient = -0.08; P < 0.05). No association was found between the APTT and air pollutant levels. In addition, no consistent relations with air pollution were found for fibrinogen, antithrombin, protein C and protein S. CONCLUSIONS: This investigation shows that air pollution is associated with changes in the global coagulation function, suggesting a tendency towards hypercoagulability after short-term exposure to air pollution. Whether these changes contribute to trigger cardiovascular events remains to be established.     

使用手性冠醚的高效毛细管电泳法研究伯胺类药物的手性分离

目的　采用HPCE法拆分伯胺类药物对映异构体。方法　缓冲液 2 0mmol/LTris 0 .1%H3 PO4(v/v)(pH 2 .0 6 ) +18 冠 6 四甲酸 (18C6H4) ;检测波长 2 10nm。结果　 8种伯胺类药物得以拆分。结论　缓冲液中添加手性冠醚的HPCE法能较好地拆分伯胺类药物。     

手性液晶的研究——Ⅸ．联苯羧酸酯类

合成了文题所述的十三个手性液晶化合物。经元素分析和红外光谱分析确证了其结构，并进行了相态、相变温度和电滞回线的测定，证实其为铁电液晶。     

Enantiomeric Resolution of Drug Compounds by Liquid Chromatography

Novel techniques have recently emerged to separate chiral drug compounds into pure enantiomers. The mechanism, experimental difficulties, and applicability of these methods can vary greatly, and the choices involved are not straightforward. The most significant new advances in the field of chiral separations have come from work done with liquid chromatographic systems and chiral stationary-phase columns. This review describes several commonly used approaches to chiral separation, diastereomeric derivatization, chiral mobile-phase additives, and three major types of chiral stationary phases. Although no single method can be judged superior for every drug application, it appears that chiral stationary phases have received the most attention recently and they are emphasized here.     

维胺酯-β-环糊精包合物的研究

应用３因素８水平的均匀设计方法，优化出维胺酯－β－环糊精包合物最佳制备条件，所得包合物的包合率为９９．３％，其表观稳定常数为１３９４Ｍ－１．     

Stereoselective distribution of tiaprofenic acid in synovium and cartilage in osteoarthritic patients

Objective: In order to document the stereoselective distribution in joints of a chiral nonsteroidal anti-inflammatory drug, the relative affinities of the enantiomers of tiaprofenic acid in synovium and for cartilage were compared. Methods: The distribution of tiaprofenic acid in synovium and in cartilage was studied 25 h after administering the racemic drug for 2 days (600 mg of a sustained-release preparation, once daily), in 12 inpatients with osteoarthritis of the hip requiring arthroplasty. Enantiomers were quantified in plasma and freeze-ground tissues by a chiral HPLC assay. Results: Plasma concentrations of the dextrorotatory (R) enantiomer (0.40 μg/ml) were higher than those of its antipode. The concentration of racemate in synovium (in dried and fresh tissues, 150% and 40%, respectively, of the concentration in plasma) was much higher than that in cartilage (in dried tissues 32% of the plasma concentration). The ratio of the active, dextrorotatory (R) enantiomer to its antipode was higher in synovial tissue than in plasma. Conclusion: Tiaprofenic acid is distributed stereoselectively in plasma and synovium, which contain a higher concentration of the active, dextrorotatory (R) enantiomer. In cartilage, it reaches only a very low concentration. Received: 26 June 1995/Accepted in revised form: 7 November 1995