1.Preparation of magnetic lidocaine microsphere and effects on sciatic nerve block in rabbits
Qian YU ; Lingxi ZHENG ; Qiang LI ; Xiaoying LU ; Chuandong ZHENG
Chinese Journal of Anesthesiology 2022;42(11):1343-1347
Objective:To develop a novel sustained-release local anesthetic microspheres and evaluate the effects on sciatic nerve block in rabbits.Methods:The magnetic lidocaine microspheres were prepared by W 1/O/W 2 compound emulsion method, investigating their external morphology, measuring the magnetic response characteristics by the VSM and draw the hysteresis loop.The encapsulation efficiency and drug-loading rate were calculated, and the cumulative release curves in vitro were drawn.Fifteen healthy rabbits (half male and half female), aged 5-6 months, weighing 3.0-3.5 kg, were selected for sciatic nerve block and divided into 3 groups ( n=5 each) using a random number table method: magnetic response lidocaine microspheres group (PL group), normal saline control group (C group) and lidocaine group (L group). Magnetic response lidocaine microsphere buffer 2 ml, normal saline 2 ml and 2% lidocaine 2 ml were injected around the rabbit sciatic nerve through a catheter in PL, C and L groups, respectively.The applied magnetic field was withdrawn at 60 h after injection.Before injection (T 0) and at 30 min and 2 , 8, 16, 24, 48, 60, 62 and 64 h after injection (T 1-9), the compound action potentials and conduction velocities of bilateral sciatic nerve trunks were measured, and block was assessed using toe reflex score and modified Tarlov score. Results:The magnetic lidocaine microspheres were brown in color and observed as monodisperse, regular spheres with a diameter of (9±3) μm, an encapsulation rate of 46.18%, a drug loading of 6.02%, and a superparamagnetic release rate of 97% in vitro at 60 h. The hysteresis loop passed through the origin and no hysteresis occurred with the absence of an external magnetic field.Compared with C group, the action potentials and conduction velocities of the sciatic nerve, toe reflex score and modified Tarlov score were significantly decreased at T 1-T 8 in PL group ( P<0.05). Compared with L group, the action potentials and conduction velocities of the sciatic nerve were significantly increased at T 1, the action potential was decreased at T 2-T 8, the conduction velocity was decreased at T 3-T 8, the toe reflex score was increased at T 1 and decreased at T 3-T 8, and the modified Tarlov score was increased at T 1 and T 2 and decreased at T 3-T 8 in PL group ( P<0.05). Conclusions:Magnetic response lidocaine microsphere is successfully developed with good magnetic responsiveness and release and can prolong the sciatic nerve block time in rabbits.
2.Potential Medication Risk Analysis of Chinese Patent Medicine in the Treatment of Stable Chronic Obstructive Pulmonary Disease
Chunxia ZHENG ; Xiaoying ZHENG ; Lingxi KONG ; Feng QIU ; Xuefeng SHAN
China Pharmacy 2020;31(7):841-844
OBJECTIVE:To study the potential ris k of Chinese patent medicine for the treatment of stable chronic obstructive pulmonary disease (COPD),and to provide reference for the safety of clinical drug use. METHODS :Retrieved from Chinese journal full-text database ,CBM,Wanfang database and VIP ,using“stable”“Chronic obstructive pulmonary disease ”“COPD” “Chinese patent medicine ”as retrieval words ,relative literatures about Chinese patent medicine in the treatment of stable COPD were retrieved ,and retrieval time limitation was from their establishment to Sept. 2019. The type and components of Chinese patent medicine were collected. The potential risk of Chinese patent medicine was analyzed in terms of the contraindications of traditional Chinese medicines ,the interaction between traditional Chinese medicines and chemical medicines ,and its effects on stable COPD with other common chronic diseases. RESULTS :Eleven related studies covering 29 kinds of Chinese patent medicines for the treatment of stable COPD were included in this study. There were several incompatibility between two Chinese patent medicines containing Aconitum carmichaelii and eleven Chinese patent medicines containing “Pinellia ternata ,Trichosanthes kirilowii , Bolbostemma paniculatum ,Ampelopsis japonica ,Bletilla striata ”as an ancient rule of traditional Chinese medicine incompatibility “Eighteen antagonisms ”and“Nineteen mutual ”inhibitors. Meanwhile ,it should be avoided that four Chinese patent medicines containing ephedra combined with β2 receptor agonists or theophylline. Moreover ,oral antibiotics and 14 kinds of Chinese patent medicine containing licorice would reduce the curative effect. In addition ,patients with stable COPD who also had hypertension , hyperlipidemia or diabetes should be careful to use Chinese patent medicines containing ingredients such as Glycyrrhiza uralensis , A. carmichaelii ,Ephedra sinica ,Citrus aurantium ,Cornus officinalis ,Fritillaria cirrhosa ,Panax ginseng (Panax notoginseng ). CONCLUSIONS:There are many potential risks (such as combined use ,compatibility)in the use of Chinese patent medicines for stable COPD. It is suggested to comprehensively evaluate the patient ’s previous medical history and medication before using Chinese patent medicines ,so as to provide scientific guide for clinical rational medication.