OBJECTIVE:To determine the content of urea in Urea [13C] capsules by high performance cation-exchange chroma-tography (HPCEC). METHODS:The determination was performed on Zorbax 300 SCX column with mobile phases consisting of acetonitrile-0.1% phosphoric acid (20:80,V/V) at the flow rate of 1.0 mL/min. The detection wavelength was set at 200 nm and column temperature was 35 ℃. The sample size was 20 μL. RESULTS:The linear range of urea was 0.0039-1.0030 mg/ml(r=0.9997). The limit of quantitation was 3.918 μg/mL and the limit of detection was 0.975 μg/mL. RSDs of precision,stability and repetitive test were all lower than 2.0%. The recovery ranged 99.3%-101.0%(RSD=0.67%,n=9). CONCLUSIONS:The meth-od is simple,rapid,sensitive and suitable for the content determination of urea in Urea [13C] capsules.

OBJECTIVE:To determine the content of acetic acid in Octreotide acetate for injection by IEC,and provide reference for the improvement of pharmacopoeia standards. METHODS:The column was Rezex ROA-Organic Acid H+ with mobile phase of 0.002 5 mol/L sulfuric acid at a flow rate of 0.5 ml/min,the detection wavelength was 210 nm,column temperature was 45℃,and in-jection volume was 100 μl. RESULTS:The linear range of acetic acid was 0.394 4 μg/ml-78.89 μg/ml(r=0.999 9);RSDs of preci-sion,stability and reproducibility tests were all lower than 2%;the limit of quantification was 197.2 ng/ml,and limit of detection was 78.89 ng/ml;recovery was 104.71%-109.78%(RSD=1.34%,n=9). CONCLUSIONS:The method is environmental and simple with good accuracy and precision,and suitable for the content determination of acetic acid in Octreotide acetate for injection.

OBJECTIVE:To determine the contents of citric acid in fentanyl citrate raw materials and its injection by ion chro-matography. METHODS:The determination was performed on Thermo Dionex IonPacTM AS11-HC column with mobile phase con-sisted of potassium hydroxide (gradient elution) at the flow rate of 1.0 mL/min. The column temperature was 35 ℃,and sample size was 20 μL. The detector was suppressed conductivity detector. RESULTS:The linear range of citric acid were 0.1157-74.05 μg/mL(r=0.9995). The limit of quantitation was 0.1150 μg/mL,and the limit of detection was 0.0400 μg/mL;RSDs of preci-sion,stability and reproducibility tests were all lower than 2.0%;the average recoveries were 99.6%-101.5%(RSD=0.68%,n=9). CONCLUSIONS:The method is environmentally-friendly and simple with good accuracy and precision,and suitable for the contents determination of citric acid in fentanyl citrate raw materials and injection.

Objective To establish a prognosis prediction scale for aspirin combined with clopidogrel in treatment of acute cerebral infarction (ACI) and evaluate its prediction effectiveness. MethodsA retrospective analysis of clinical features of 202 ACI patients, admitted to and accepted aspirin combined with clopidogrel in our hospital from October 2017 to April 2019, was performed. According to the differences of National Institutes of Health Stroke Scale (NIHSS) scores before and after treatment, the patients were divided into good prognosis group and poor prognosis group; univariate and multivariate Logistic regression analyses were used to screen the independent risk factors for prognoses of acute cerebral infarction; assignment of these factors was performed, respectively, to establish prediction scale; and finally the prediction scale was applied to the patients for verification.ResultsOf the 202 patients, 167 had a good prognosis and 35 had a poor prognosis. Multivariate Logistic regression analysis revealed that age≥50 years, hypertension, homocysteine, and carotid stenosis≥50％ were independent risk factors for prognoses 14 d after onset in patients with ACI (P< 0.05); the assigned values of age≥50 years, hypertension grading I, hypertension grading II, hypertension grading III, homocysteine, and 中华神经医学杂志2019年11月第18卷第11期Chin J Neuromed, November 2019, Vol.18, No.11 carotid stenosis≥50％ were 1, 1, 2, 3, 1, and 1, respectively; the total pridiction scale scores were 0-6. Validation results showed that the poor prognosis rate of patients with predictive scale scores≥3 was 91.3％ (157/172) and that of patients with predictive scale scores<3 was 33.3％ (10/30).Conclusion The predictive scale established in this study can be used to quickly and accurately identify patients with acute cerebral infarction who are suitable for aspirin combined with clopidogrel.

Objective To analyse the risk factors associated with spontaneous intestinal perforation (SIP) in extremely premature infants/extremely low birth weight infants. Method From January 2015 to December 2018, infants with gestational age (GA)<28 weeks or birth weight (BW)<1000 g admitted to our neonatal intensive care unit were enrolled to the retrospective nested case-control study.The clinical data of SIP infants (SIP group) and infants with the same GA but without SIP (control group) were randomly selected and compared. Multivariable Logistic regression was used to analyse the risk factors of SIP. Result A total of 409 extremely premature infants/extremely low birth weight infants were born during the study period. Among them, 25 SIP infants and 55 controls were enrolled. The incidence of SIP in infants with GA 22～25 weeks was 11.8％(16/136), which is higher than infants with GA 26～27 weeks (2.0％, 5/247) (χ2=16.057, P<0.001). The incidence of SIP in infants with BW 400～749 g was 13.0％(14/108), which is higher than infants with BW 750～999 g (3.4％, 8/236) (χ2=11.343, P=0.001). Multivariate Logistic regression analysis showed that twins (OR=4.153, 95％CI 1.392～12.384, P=0.011), umbilical veins catheterization (OR=15.942, 95％CI 1.026～247.789, P=0.048) and ibuprofen use within 3 days after birth (OR=15.387, 95％CI 1.519～155.883, P=0.021) were independent risk factors of SIP. Conclusion The smaller the GA and BW, the higher the incidence of SIP. Twins,umbilical veins catheterization and ibuprofen use early after birth may be independent risk factors of SIP.

Objective To investigate the feasibility of computer-aided pancreas segmentation based on three-dimensional (3D) Dixon MRI at 3.0-T.Methods Five volunteers with health pancreas underwent upper abdominal 3D Dixon MRI at 3.0T with the same scan parameters while holding breath.The automatic segmentation of pancreas is based on the Medical Imaging Interaction ToolKit (MITK) with homemade software.A experienced radiologist performed manual segmentation and computer aided segmentation of the pancreas on the opposed phase and water phase images twice.Similarity was analyzed and compared for the manual and automated segmentations for the two group images.Similarity was presented as Dice coefficients.Results Both of the oppose phase and water phase images of Dixon MRI showed that the signal intensity of pancreas was higher than that of the surrounding tissue,the similarity of water phase was obviously higher than that of oppose phase and the differences were statistically significant.Based on Dixon MRI water phase and oppose phase images,the mean dice coefficients for the manual segmentations were 0.81 ± 0.01 and 0.85 ±0.03,respectively,for both the oppose phase and water phase images (P=0.013).For the automated segmentations,the dice coefficients were 0.69 ± 0.08 and 0.75 ± 0.03 for water phase images and the oppose images,respectively,and the difference was not statistically significant (P =0.155).Conclusions 3.0T oppose phase and water phase of Dixon images could clearly show the pancreas,and automated pancreas segmentation based on water phase Dixon MRI obtained higher similarity,which was feasible.

Objective: To investigate the association between hepatic controlled attenuation parameter (CAP) and metabolic syndrome (MetS) and the correlation of CAP and its changes with the incidence of MetS. Methods: A total of 2461 subjects who underwent physical examination from July 2013 to September 2015 were enrolled. Spearman correlation analysis was used to investigate the correlation of CAP with the number of MetS components and each MetS component, and the chi-square test was used to investigate the prevalence rates of MetS and each component under different CAP levels. Logistic regression analysis was used to analyze the odds ratio (95% confidence interval (CI)) of MetS under different CAP levels. A total of 230 subjects without baseline MetS were selected; in a prospective cohort study, these subjects were divided into groups according to the baseline CAP, change in CAP, and percent change in CAP, and the chi-square test was performed to compare the incidence of MetS. The Cox regression analysis was used to analyze the values of baseline CAP, change in CAP, and percent change in CAP in predicting MetS. Results: CAP was positively correlated with the number of MetS components (r = 0.309, P < 0.01) and significantly correlated with all components. There were significant differences in the prevalence rates of MetS and its components under different CAP levels (< 238 dB/m, 238-258 dB/m, 259-291 dB/m, and ≥292 dB/m) (P < 0.05). After the adjustment for sex and age, with < 238 dB/m as a reference, the odds ratios (95% CI) of MetS in patients with CAP levels of 238-258 dB/m, 259-291 dB/m, and ≥292 dB/m were 1.784 (1.369-2.325), 2.936 (2.292-3.760), and 4.363 (3.435-5.543), respectively (all P < 0.05). Follow-up data showed that 28 patients (12.2%) developed MetS. After the adjustment for related factors, the hazard ratios (95% CI) of MetS in patients with baseline CAP > 238 dB/m, change in CAP > 30 dB/m, and percent change in CAP > 25.0% were 3.337 (1.163-9.569), 7.732 (2.453-24.366), and 11.656 (3.329-40.813), respectively (all P < 0.05). Conclusion CAP is closely associated with MetS and its components. CAP and its change can be used to predict the risk of MetS.