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.

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.
Algorithms ; Heart Valve Diseases ; diagnostic imaging ; Humans ; Likelihood Functions ; Mitral Valve ; diagnostic imaging ; pathology ; Patient Positioning ; Probability ; Ultrasonography

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.

Abstract: To date, the investigation of the functional composition of Centella asiatica (L.) Urban has been mainly focused on the triterpenoid saponins, with little research on the other compositions. The acetic acid-induced writhing, Eddy's hot plate and formalin tests were employed to investigate the anti-nociceptive effects of madecassic acid (MA). The experiment was divided into normal control group, acetylsalicylic acid (ASA) group, and the MA groups of low (10 mg/kg), medium (20 mg/kg) and high (40 mg/kg) dosage. Meanwhile, the anti-nociceptive effect of MA on the acetic acid and formalin-induced nociceptive models in the absence and presence of NAL (naloxone hydrochloride) was evaluated. To have an insight into the anti-nociceptive mechanisms of MA, the capsaicin- and glutamate-induced paw licking tests were also employed to evaluate the involvement of the vanilloid and glutamatergic systems, respectively. Results showed that MA exhibited good anti-nociceptive activity in the acetic acid-induced writhing test and the second phase of formalin test; the anti-nociceptive effect of MA in both the acetic acid and formalin-induced nociception was not effectively removed by NAL; MA (20 mg/kg and 40 mg/kg) effectively reduced the duration of biting/licking the capsaicin-injected paw with inhibition rates of 29.5% and 64.4%, respectively; MA (20 mg/kg and 40 mg/kg) distinctly shortened the time spent in biting/licking the glutamate-injected paw by 30.9% and 56.1%, respectively. In summary, MA induces significant peripheral anti-nociceptive effect, and the anti-nociceptive activities probably involve the modulation of glutamatergic systems and vanilloid systems (TRPV1) instead of the opioidergic system.

Objective To make a conclusion about the methods and main points of surgical position for cervical artificial disc replacement (CADR). Methods We collected the data from January to December 2015 in West China Hospital of Sichuan University. It included 102 patients in the surgical group of cervical spine, which were cervical vertebra degeneration and doing CADR according to the segment, quantity of the replacement and whether belonged to hybrid surgical method, then we analyzed and determined how to achieve the desired surgical position. Results The surgical positions of the patients in this group all conformed to the requirements of the replacement and gave intraoperative excellent exposure and less blood loss, made the vision of decompression clear and thorough, made the position of replacement prosthesis great. There were no postoperative complications. The patients all healed and were discharged in 5 to 7 days after operation. There was no position offset of prosthesis and no extrusion in the following 6 to 18 months. It restored the ideal physiological lordosis of the cervical spine. Conclusions According to the different segment of the replacement, we analyze and remain the location of the preoperative cervical spinal neutrality and a bit of extension which make the artificial cervical disc in favor of being well placed during an operation and promote cervical spine to maintain normal physiological lordosis during early post-operation, and greatly reduce the incidence of postoperative pain of neck and shoulder.

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.

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.

Objective The Kellinghaus grading method was used to manually read and grade the thin-layer CT of sternal end of clavicle,and a variety of traditional statistical methods as well as machine learning methods were used to construct age estimation models for adolescents and adults in early adulthood,to explore the value of the application of machine learning technology in the study of age estimation of the Han Chinese population in Sichuan.Methods Thin-section CT images of the chest were retrospectively collected from 491 individuals aged 10～30 years,and the collected samples were assigned a reading grade with reference to the Kellinghaus grading method.10%of the xases were randomly selected as the test set,and the remaining data were used as the training set to construct a variety of traditional statistical regression models and machine learning models for estimating the age of adolescents and adults in early adulthood,and the performance of the models was evaluated by using the mean absolute error(MAE).Results The statistical regression model with the best efficacy was the cubic regression model,with an MAE value of 1.34 for males and 1.57 for females;of the three machine learning models,the Random Forest model had the best predictive efficacy for males,with an MAE value of 1.39,and the Support Vector model had the best predictive efficacy for females,with an MAE value of 1.51.Conclusion In the construction of age estimation models for sternal end of clavicle,the machine learning model has a certain improvement in the accuracy of age prediction,but there is no obvious advantage compared with the traditional statistical regression model,and the use of the machine learning method in age estimation based on sternal end of clavicle still needs further exploration.

With the improvements in surgical technique,the indications for liver transplantation(LT)are being expanded to more complex and severe patients,who not only have liver function in the terminal stage,but also extrahepatic organs involve of varying degrees dysfunction.It was demonstrated that the strategy of extrahepatic organs management in early period after LT was associated with improving recovery.This paper summarized the strategy of extrahepatic organs management in early period after adult LT.Continuing to monitor system hemodynamics is helpful for stable graft perfusion.It is necessary to manage derangements of preload,myocardial contractility,and afterload.Early postoperative extubation is recommended by current guidelines.Routine screening pulmonary complications may help weaning from the ventilator.The diagnosis of acute kidney injury(AKI)after LT has been reported to using Kidney Disease:Improving Global Outcomes(KDIGO)criteria,a delayed calcineurin inhibitor initiation strategy may be beneficial for renal protection.Currently,there is no consensus on timing of renal replacement therapy initiation in patients with AKI.Patients with cirrhosis and a history of hepatic encephalopathy(HE)displays impaired neurological recovery,the diagnosis of HE is crucial and challenging.

Objective:To investigate the correlation between pen-holding posture, grip strength and myopia.Methods:A cross-sectional study was performed.A total of 496 school-aged children in grades 1-6, who underwent eye examinations at Shenzhen Eye Hospital from November 2021 to May 2022 were consecutively enrolled as subjects.The subjects' age, grade, sex, refractive error and age of school enrollment were recorded.Subjects' grip strength and pen-holding posture were obtained with an electronic grip strength meter and a tool pen, and subjects were divided into correct pen-holding posture group and incorrect pen-holding posture group according to their pen-holding posture.Propensity scores for sex, grade, age at school entry, and grip strength in the two groups were matched using the nearest neighbor matching method.Multifactorial binary logistic regression analysis was performed with binocular myopia, monocular myopia, and emmetropia as dependent variables and grip strength, grade, refractive error, and pen-holding posture as independent variables.The correlation between grip strength and spherical equivalent was examined by Spearman rank correlation analysis and partial correlation analysis.This study protocol adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Shenzhen Eye Hospital (No.2022KYPJ032).Results:After matching propensity scores, there were 101 cases and 197 cases in the correct pen-holding posture group and incorrect pen-holding posture group, respectively.There was no statistical significance in sex, grade, age at enrollment, and grip strength between the two groups (all at P>0.05).Multinomial logistic regression results showed that using emmetropia as a reference, higher grade (4 versus 1∶7.601[1.307-44.206]; 5 versus 1∶4.392[1.039-18.562]), presence of anisometropia (21.366[5.750-79.397]) were relative risk factors for monocular myopia (all at P<0.05), and higher grade (3 versus 1∶4.389[1.783-10.800]); 4 versus 1∶15.398[3.267-72.574]; 5 versus 1∶7.447[2.232-24.851]; 6 versus 1∶6.462[2.116-19.734]) were relative risk factors for binocular myopia (all at P<0.05).Taking monocular myopia as a reference, higher grade (6 versus 1∶4.582[1.193-17.589]), presence of anisometropia (0.141[0.069-0.289]), and irregular pen-holding posture (2.608[1.340-5.075]) were associated factors for binocular myopia (all at P<0.05).According to partial correlation analysis, the spherical equivalent of the right eye of children with incorrect pen-holding posture was negatively correlated with the grip strength ( rs=-0.141, P=0.047). Conclusions:There is an association between pen-holding posture and myopia in school-aged children.Children with greater grip strength and incorrect pen-holding posture may have higher degrees of right eye refractive error.