2.Three-dimensional finite element analysis on biomechanical changes after arthroscopic surgery for patients with patellofemoral joint disorders
Journal of Medical Biomechanics 2017;32(2):143-147
Objective To analyze stress distribution changes in patellofemoral joints before and after arthroscopic surgery by lateral retinacular release and medial retinaculum placation using three-dimensional (3D) finite element method.Methods The 3D finite element model of pre-and post-operative patellofemoral joints for patients with patellofemoral joint disorders were constructed,and the maximum stress and stress distributions on patelIofemoral joints at different flexion angles (30.,60.,90.,120.) under the load of 120 N were calculated and analyzed.Results The maximum stress of patellofemoral joints at different flexion angles after arthroscopic surgery was significantly smaller than that before arthroscopic surgery.The stress concentrated on the lateral patellofemoral joints before the surgery,but was redistributed after the surgery.Conclusions The stress on patellofemoral joints at different flexion angles is reduced after arthroscopic surgery by lateral retinacular release and medial retinaculum placation,which provides an objective theoretic reference for arthroscopic surgery to effectively restore stress balance between lateral and medial patellofemoral joints.It is suggested that patients with early patellofemoral joint disorders and abnormal force line should be treated with surgery intervention as early as possible.
3.Three-dimensional finite element analysis on biomechanical changes after arthroscopic surgery for patients with patellofemoral joint disorders
Journal of Medical Biomechanics 2017;32(2):E143-E147
Objective To analyze stress distribution changes in patellofemoral joints before and after arthroscopic surgery by lateral retinacular release and medial retinaculum placation using three-dimensional (3D) finite element method. Methods The 3D finite element model of pre-and post-operative patellofemoral joints for patients with patellofemoral joint disorders were constructed, and the maximum stress and stress distributions on patellofemoral joints at different flexion angles (30°,60°,90°,120°) under the load of 120 N were calculated and analyzed. Results The maximum stress of patellofemoral joints at different flexion angles after arthroscopic surgery significantly smaller than that before arthroscopic surgery. The stress concentrated on the lateral patellofemoral joints before the surgery, but was redistributed after the surgery. Conclusions The stress on patellofemoral joints at different flexion angles is reduced after arthroscopic surgery by lateral retinacular release and medial retinaculum placation, which provides an objective theoretic reference for arthroscopic surgery to effectively restore stress balance between lateral and medial patellofemoral joints. It is suggested that patients with early patellofemoral joint disorders and abnormal force line should be treated with surgery intervention as early as possible.
4.Comparison of two vasopressor protocols for preventing hypotension post-spinal anesthesia during cesarean section: a randomized controlled trial.
Qian-Qian FAN ; Yong-Hui WANG ; Jing-Wen FU ; Hai-Long DONG ; Man-Ping YANG ; Duo-Duo LIU ; Xiao-Fan JIANG ; Zhi-Xin WU ; Li-Ze XIONG ; Zhi-Hong LU
Chinese Medical Journal 2021;134(7):792-799
BACKGROUND:
Norepinephrine infusion decreases hypotension after spinal anesthesia during cesarean section. This study aimed to compare the efficacy of norepinephrine infusion and ephedrine bolus against post-spinal hypotension in parturients.
METHODS:
In this double-blinded, randomized controlled clinical trial, parturients scheduled for elective cesarean section were randomly allocated to receive norepinephrine infusion (0.05 μg·kg-1·min-1) just before spinal anesthesia continuing for 30 min or ephedrine bolus (0.15 mg/kg) just before spinal anesthesia. A rescue bolus (5 μg norepinephrine for the norepinephrine group, and 5 mg ephedrine for the ephedrine group) was administered whenever hypotension occurred. Our primary outcome was the incidence of hypotension within 30 min of spinal anesthesia administration. Secondary outcomes included maternal and neonatal outcomes 30 min after spinal block, and neonatal cerebral oxygenation 10 min after birth.
RESULTS:
In total, 190 patients were enrolled; of these patients, 177 were included in the final analysis. Fewer patients suffered hypotension in the norepinephrine group than in the ephedrine group (29.5% vs. 44.9%, odds ratio [OR]: 0.51, 95% confidence interval [CI]: 0.28-0.95, P = 0.034). Moreover, the tachycardia frequency was lower in the norepinephrine group than in the ephedrine group (OR: 0.22, 95% CI: 0.11-0.44, P < 0.001), and patients suffered less nausea and vomiting (OR: 0.28, 95% CI: 0.11-0.70, P = 0.004). There was no difference in Apgar scores and umbilical arterial blood gas analysis between the two groups. However, neonatal cerebral regional saturations were significantly higher after birth in the norepinephrine group than in the ephedrine group (mean difference: 2.0%, 95% CI: 0.55%-3.45%, P = 0.008).
CONCLUSION:
In patients undergoing elective cesarean section with spinal anesthesia, norepinephrine infusion compared to ephedrine bolus resulted in less hypotension and tachycardia, and exhibited potential neonatal benefits.
TRIAL REGISTRATION
ClinicalTrials.gov, NCT02542748; https://clinicaltrials.gov/ct2/show/record/NCT02542748.
Anesthesia, Spinal/adverse effects*
;
Cesarean Section/adverse effects*
;
Double-Blind Method
;
Female
;
Humans
;
Hypotension/prevention & control*
;
Infant, Newborn
;
Phenylephrine
;
Pregnancy
;
Randomized Controlled Trials as Topic
;
Vasoconstrictor Agents/therapeutic use*
5.Research on anticancer activity of isocorydine and its derivatives.
Qian YAN ; Ru-Xia LI ; Ai-Yi XIN ; Jun-Xi LIU ; Wen-Guang LI ; Duo-Long DI
China Journal of Chinese Materia Medica 2017;42(16):3152-3158
Isocorydine and its analogs were extracted from Dicranostigma leptopodum and Stephania yunnanensis through the method of natural products chemistry. Its derivatives were prepared by chemical structure modifications from isocorydine. MTT method was used to study the inhibitory effect of those compounds on the growth of HepG2, HeLa and MGC-803 cancer cell lines in vitro. The results showed that isocorydine and its analogs all have the growth inhibition for those cancer cell lines. This paper investigated the structure-activity relationship of isocorydine and its derivatives with anticancer activity in the aspect of stereochemical structure, functional groups positions of the compounds and the electron density of aromatic rings based on the single crystal diffraction structure and the molecular docking of EGFR and isocorydine.