1.The dynamic observation of plasma concentration of antimicrobial agents during balanced ultrafiltration in vitro
Zhida FU ; Yulong GUAN ; Juanjuan JIANG ; Chunfu WU ; Ju ZHAO ; Peng SUN ; Cun LONG
Chinese Journal of Thoracic and Cardiovascular Surgery 2013;29(11):675-678,684
Objective Routine perioperative intravenous antimicrobial agents,was administered as surgical prophylaxis.However,whether balanced ultrafiltration during extracorporeal circulation can remove antimicrobial agent remains unclear.The concentrations of antimicrobial agent in plasma and ultrafiltrate samples were measured in this pseudo-extracorporeal circulation model.Methods Extracorporeal circulation consisted of cardiotomy reservoir (Ningbo Fly Medical Healthcare CO.,LTD.Ningbo,China),D902 Lilliput 2 membrane oxygenator (Sorin Group Asia Pte Ltd,Beijing,China) and Capiox (R) AF02 pediatric arterial line filter (Terumo Corporation,Beijing,China).HEMOCONCENTRATOR BC 20 plus (MAQUET Cardiopulmonary AG,Hirrlingen,Germany) was placed between arterial purge line and oxygenator venous reservoir.Fresh donor human whole blood was added into the circuit and mixed with Ringer's solution to obtain a final hematocrit of 24%-28 %.After 30 minutes of extracorporeal circulation,zero-balanced ultrafiltration was initiated and arterial line pressure was maintained at approximately 100 mm Hg(1 mm Hg =0.133 kPa) with Hoffman clamp.The rate of ultrafiltration (12 ml/min) was controlled by ultrafiltrate outlet pressure.Identical volume of plasmaslyte A was dripped into the circuit to maintain stable hematocrit during 45 minutes of experiment.Plasma and ultrafiltrate samples were drawn every 5 minutes and concentrations of antimicrobial agent (including Cefmetasole and cefotiam) were measured with high performance liquid chromatography.Results All these two antimicrobial agents were detected in ultrafiltrate,demonstrating hemoconcentration may remove antimicrobial agent.The concentration of plasma antimicrobial agent decreased lineally with the increase of ultrafiltrate volume.At end of balanced ultrafiltration,the concentration of plasma cefotiam was (104.96 ± 44.36) μg/ml,which is about (44.38 ± 7.42) % of the initial concentration (238.95 ± 101.12) μg/ml; the concentration of plasma cefmetazole decreased linearly to (25.76 ± 14.78) μg/ml,which is about (49.69 ± 10.49) % of the initial concentration (51.49 ± 28.03) μg/ml.The total amount of cefotiam in ultrafiltrate is (27.16 ± 12.17)% of the total dose administered,whereas cefmetasole in ultrafiltrate is (7.74 ±4.17)%.Conclusion Balanced ultrafiltration may remove antimicrobial agent from serum and has significant influence on plasma concentration of antimicrobial agent.The strategy of surgical prophylaxis should consider this unique technique during extracorporeal circulation.
2.Effects of fibroblast growth factor inducible 14 (Fn14) on high glucose induced-cardiomyocyte hypertrophy
Jiefang ZHANG ; Zhida SHEN ; Lu YU ; Wenbing JIANG ; Zhengwei LI ; Guosheng FU
Chinese Journal of Endocrinology and Metabolism 2016;32(5):411-414
Objective To investigate the effect and mechanisms of factor fibroblast growth factor inducible 14(Fn14)in the high glucose induced-cardiomyocyte hypertrophy. Method To observe the expression of collagenⅠ, connective tissue growth factor ( CTGF ) , transforming growth factor-β1 ( TGF-β1 ) , and Fn14 in high glucose induced-cardiomyocyte hypertrophy. Fn14 expressions was down-regulated by siRNA interference technique, and then the expressions of collagen Ⅰ, CTGF, and TGF-β1 were observed, and the mechanism was also explored. Results The expression of collagen I, CTGF and TGF-β1 was significantly up-regulated after high glucose induced-cardiomyocyte hypertrophy for 72 h. At the same time, the expression of Fn14 was increased after 72 h-treatment, and reached the peak at concentration of 30 mmol/L high glucose. High glucose could not up-regulated the expression of collagenⅠ, CTGF, and TGF-β1 after siFn14 interference, while the same result was observed in the expression of p-JNK. Conclusion The expressions of collagenⅠ, CTGF, TGF-β1, and Fn14 in cardiomyocyte of neonatal rats were induced by high glucose. While Fn14 expression was inhibited, the expressions of collagenⅠ, CTGF, and TGF-β1 were down-regulated, which seems to be involved with p-JNK signaling pathway.