Meibomian Gland Morphology Changes After Cataract Surgery: A Contra-Lateral Eye Study.

Purpose: To evaluate the morphology changes of meibomian glands (MGs) after cataract surgery. Setting: Hangzhou Branch of the Eye Hospital of Wenzhou Medical University, Zhejiang, China. Methods: In this contra-lateral eye study, 40 patients received unilateral cataract surgery for age-related cataract. All the patients underwent the evaluation of non-invasive break-up time (NIBUT) and lower tear meniscus height (TMH) before the surgery and 6 months post-operatively. The MGs were evaluated via ImageJ and Meibomian Gland Bio-image Analyzer. MG dropout, length, width, area, gland diameter deformation index (DI), and gland signal index (SI) were recorded. Results: MG length, width, area, DI, and SI were significantly decreased after cataract surgery in the study group (operated eyes, P < 0.001, P = 0.003, P < 0.001, P = 0.001, and P < 0.001, respectively) and showed no significant changes in the control group (non-operated eyes) (all P > 0.05). MG loss increased more in the study group (P = 0.030), and the changes in TMH and NIBUT were not significantly different between the two eyes (both P > 0.05). Conclusion: Cataract surgery aggravated meibomian gland morphology, such as MG loss, MG length, width, area, and SI, and produced no change in NIBUT and TMH at 6 months post-operatively.

Application of an HPLC correction factor method in pharmaceutical analysis / 药学学报

With the in-depth study of related substances and the development of consistency evaluation of generic drugs, relative correction factors are gaining increasing attention. By analyzing the domestic and foreign literature on correction factors in recent years, this paper describes the correction factor component, the current measurement method and its application. The rules and key points of use of an impurity correction factor and its determination and application are described, and some problems in its determination and application are discussed, providing a reference and basis for the standardization of research on impurity correction factors in the future.

HPLC method with correction factor for determination of related substances in compound ezetimibe and rosuvastatin calcium tablets / 中国药学杂志

OBJECTIVE: To establish the self contrast and correction factor method for the content determination of the related substances in compound ezetimibe and rosuvastatin calcium tablets simultaneously. METHODS: RP-HPLC method was adopted. The determination was performed on Kromasil 100-5 C18 Dimensions column (4.6 mm × 250 mm, 5 μm) with mobile phase A consisting of methanol-acetonitrile-0.05 mol·L-1 potassium dihydrogen phosphate (adjusted to pH 4.0 with phosphoric acid) (10:30:60) and mobile phase B consisting of tetrahydrofuran-acetonitrile-0.05 mol·L-1 potassium dihydrogen phosphate (adjusted to pH 4.0 with phosphoric acid) (10:50:40) at a flow rate of 1.0 mL·min-1. The detection wavelength was set at 242 nm. The injection volume was 20 μl. The slope of linear equation was used to determine the correction factors between ROS impurities 1, 2, 3, EZT impurities 1, 2, 3, 4, 5, 6, 7 and ezetimibe or rosuvastatin calcium. The relative retention time was used to determine the positions of impurities. RESULTS: The relative retention time of ROS impurities 1, 2, 3, 4 and EZT impurities 1, 2, 3, 4, 5, 6, 7 to rosuvastatin calcium was 1.5, 1.9, 2.1, 1.1, 1.7, 2.5, 2.6, 2.8, 2.9, 3.0, and 4.0, respectively. The correction factors of ROS impurities 1, 2, 3, 4 and EZT impurities 1, 2, 3, 4, 5, 6, 7 were 1.1, 1.1, 1.0, 1.0, 1.3, 1.1, 1.0, 1.3, 1.4, 0.5, and 1.0, respectively. The content of ROS impurity 4 was 0.15% in three batches of samples, the other impurities were less than 0.1%, and the contents of total impurities were 0.27%, 0.27%, and 0.26%, respectively. CONCLUSION: The method is simple, efficient, and accurate for analyzing the related substances in compound ezetimibe and rosuvastatin calcium tablets.

A self-contrast approach to evaluate the inhibitory effect of chrysosplenetin, in the absence and presence of artemisinin, on the in vivo P-glycoprotein-mediated digoxin transport activity.

In this study, we used a self-contrast method, which excluded the individual difference, to evaluate the inhibitory effect of chrysosplentin (CHR) in the presence or absence of artemisinin (ART) on the P-glycoprotein (P-gp) transport activity. A sensitive and rapid UHPLC-MS/MS method was applied for quantification of digoxin, a P-gp-specific substrate, in rat plasma. A pharmacokinetic study was carried out: first after an oral administration of digoxin at a dose of 0.09 mg/kg (first period), followed by a 20-day wash-out, then after another administration of digoxin (second period). During the second period, test compounds were orally given three times per day for seven consecutive days. Results showed that the t1/2 of digoxin in all the groups had no significant difference between the first and second periods. The AUC0-24 , Cmax , tmax , and Clz /F of the negative control and ART alone groups showed no difference. However, the AUC0-24 and Cmax in the CHR alone, CHR-ART (1:2) and verapamil (positive control) groups showed 2.34-, 3.04-, 1.79-, and 1.81-, 1.99-, 2.06-fold increases along with 3.50-, 3.84- and 4.76-fold decreases for CLz /F, respectively. The tmax in the CHR-ART (1:2) group increased 3.73-fold. In conclusion, our self-contrast study suggested that CHR, especially when combined with ART in a ratio of 1:2, inhibited P-gp activity while ART alone has no effect. Copyright © 2016 John Wiley & Sons, Ltd.

Determination of Six Main Flavonoids in Herba Epimedii by Self Contrast with Correction Factor / 中国药师

Objective:To determine the content of six main flavonoids in herba epimedii by self contrast with correction factor. Methods:HPLC was carried out with reversed-phase technique on an Agilent ZORBAX Eclipse XDB-C18 (150 mm × 4. 6 mm, 5 μm) column with the mobile phase consisting of acetonitrile-water with gradient elution. The detection wavelength was 268nm and the col-umn temperature was 30℃. The correction factor was established through the increase value of chromatographic peak area for the self internal standard. The relative retention time and spectrum reference method were used to determine the position of impurities. Re-sults:The relative retention time of epimedin A1 , epimedin A, epimedin B, epimedin C and baohuoside I was 0. 750,0. 810,0. 865, 0. 939 and 1. 651, respectively. The correction factor of them was 0. 998 6, 0. 998 7, 0. 998 8, 0. 989 4 and 0. 985 6, respectively. Conclusion:The self contrast with correction factor can be use to quantitatively determine the components with the same kind of chem-istry environment. The method is simple, efficient and accurate in the quantitative analysis of multi components in Chinese medicines.