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Objective To evaluate the effect of coagulation function changes on the incidence of acute kidney injury (AKI) after liver transplantation. Methods Clinical data of 245 liver transplant recipients who met the inclusion and exclusion criteria were retrospectively analyzed. According to the incidence of AKI after liver transplantation, all recipients were divided into the AKI group (n=99) and non-AKI group (n=146). The incidence of AKI after liver transplantation was summarized. Perioperative parameters of the recipients were collected. The risk factors of AKI after liver transplantation were assessed by univariate and multivariate analysis. Results Among 245 recipients undergoing liver transplantation, 99 cases developed AKI after operation with an incidence rate of 40.4%. Preoperative serum creatinine levels of the recipients and the in-hospital fatality were relatively high in the AKI group (all P < 0.05). Compared with the recipients in the non-AKI group, those in the AKI group presented with significantly higher liver function parameters within postoperative 24 h, significantly decreased levels of stage Ⅱ coagulation parameters including coagulation factorsⅤ, Ⅶ, Ⅸ, Ⅹ, Ⅻ and protein S, protein C and antithrombin Ⅲ, evidently elevated prothrombin time international normalized ratio (PT-INR), remarkably increased stage Ⅲ coagulation parameters including D-dimer and fibrin degradation product (FDP) levels and considerably decreased fibrinogen (FIB) level (all P < 0.05). Thrombelastogram showed that the R value was increased, the α angle was decreased and the coagulation time was prolonged in the AKI group (all P < 0.05). Logistic regression analysis demonstrated that the increased R value of postoperative thrombelastogram [odd ratio (OR) 1.116, 95% confidence interval (CI) 1.018-1.223, P=0.019], and decreased levels of antithrombin Ⅲ (OR 0.974, 95%CI 0.955-0.993, P=0.007) were the independent risk factors of incidence of AKI after liver transplantation. Conclusions The incidence of AKI after liver transplantation is high, which is associated with the coagulation function changes of the recipients. Decreased coagulation factor activity (increased R value) and declined antithrombin Ⅲ level are the independent risk factors of AKI in liver transplantat recipients.
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OBJECTIVE:To optimize the synthesis technology of 4-biphenylacetic acid,and to provide technology support to meet the market demand of 4-biphenylacetic acid raw material. METHODS:The synthesis route of 4-biphenylacetic acid from biphenyl by Friedel-Crafts reaction,ketal reaction,rearrangement reaction and hydrolysis was optimized and improved. The effects of different Friedel-Crafts reaction solvents (petroleum ether,dichloromethane,1,2-dichloroethane),ketal reaction ethanol (ethanediol, 1,3-propanediol, dimethyltrimethylene glycol, pentaerythritol), rearrangement reaction catalyzer (zinc biphenyl acetate,zinc oxide,zinc caprylate,zinc acetate) and refined solvent (isopropanol,95% isopropanol,ethanol,acetone,ethyl acetate) on synthesis technology were investigated. The optimal synthesis technology was screened with the purity and yield of intermediate or 4-biphenylacetic acid. RESULTS:The petroleum ether as Friedel-Crafts reaction solvent,ethylene glycol as ketal reaction ethanol,zinc diphenylacetate as rearrangement catalyst and 95% isopropanol as refining solvent were used for the preparation to obtain better effects. The yield of key intermediate 2′-chloroacetophenone reached above 95%. The purity of refined 4-biphenylacetic acid reached 99.9%;the content of single impurity was less than 0.1%;the total yield reached over 70%. CONCLUSIONS:The optimal synthesis technology of 4-biphenylacetic acid has the advantages of simple operation,mild and controllable reaction conditions,low cost,greener reagents and higher safety,and is suitable for industrial production. The purity and yield of the products are in high level and in line with the standards of European Pharmacopoeia and the Japanese Pharmacopoeia.
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OBJECTIVE:To establish a method for simultaneous determination of 5 kinds residual ethanol,acetone,ethylacetate,N,N-diisopropylethylamine and toluene in favipiravir.METHODS:Headspace GC was adopted.The determination was performed on DB-624 capillary column,temperature programmed.The inlet temperature was 220 ℃,and detector was flame ionization detector with temperature of 250 ℃.Nitrogen was used as carrier gas at flow rate of 2.0 mL/min,split ratio was 10 ∶ 1,headspace equilibrium temperature was 80 ℃,equilibrium time was 20 min and headspace sample size was 1 mL.RESULTS:The linear range was 10.0-501.4 μg/mL for ethanol(r=0.999 9),10.0-501.4 μg/mL for acetone (r=0.999 9),10.1-502.6 μg/mL for ethylacetate (r=0.999 9),0.2-11.4 μg/mL for N,N-diisopropylethylamine (r=0.999 9)and 1.8-89.4 μg/mL for acetone(r=0.999 7).The limits of quantification were 5.3,3.4,5.2,6.1 and 20.4 μg/mL,and the limits of detection were 1.4,1.1,1.3,1.6,5.9 μg/mL.RSD of precision test was lower than 4.0％,and RSDs of acetone in stability and reproducibility tests were both lower than 4.0％.The recoveries were 96.61％-99.70％ (RSD=1.01％,n=9),95.81％-99.50％ (RSD=1.29％,n=9),96.42％-99.76％ (RSD=1.24％,n=9),96.36％-99.30％ (RSD=1.19％,n=9),97.00％-99.51％ (RSD=0.82％,n=9).CONCLUSIONS:The method is simple,accurate,reproducible and can be used for simultaneous determination of 5 organic solvents in favipiravir.
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OBJECTIVE:To improve the synthesis technology of sodium picosulfate. METHODS:The synthesis technology of sodium picosulfate was improved by changing reaction solvent,charging sequence,refined method and formation of crystal water. Using phenol as raw material,it was condensed with 2-pyridinecarboxaldehyde to achieve 4,4′-(pyridin-2-ylmethylene)diphenol, and its yield rate was investigated. Sodium picosulfate was obtained after esterification,salification,formation of crystal water, and then its purity was determined. RESULTS:The yield rate of key intermediate 4,4′-(pyridin-2-ylmethylene) diphenol reached above 88%,and the purity of refined products reached over 99.5%. Sodium picosulfate monohydrate was stable,and the content of single impurity was less than 0.1%. CONCLUSIONS:The improved technology is simple with mild conditions,and suitable for large-scale production.
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Mitral valve disease is one of the most popular heart valve diseases. Precise positioning and displaying of the valve characteristics is necessary for the minimally invasive mitral valve repairing procedures. This paper presents a multi-resolution elastic registration method to compute the deformation functions constructed from cubic B-splines in three dimensional ultrasound images, in which the objective functional to be optimized was generated by maximum likelihood method based on the probabilistic distribution of the ultrasound speckle noise. The algorithm was then applied to register the mitral valve voxels. Numerical results proved the effectiveness of the algorithm.