OBJECTIVE To determine the contents of N-nitroso impurities in raw materials/formulations of propranolol， metoprolol， atenolol， esmolol and bisoprolol， and clarify the attention threshold. METHODS Ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry（UPLC-Q/Orbitrap HRMS）was adopted. An ACE Excel 3 C18-AR column was used for the separation and a mixture of 0.2% formic acid solution with 0.01 mol/L ammonium acetate and methanol was employed as the mobile phase by gradient elution， at a flow rate of 0.60 mL/min. The column temperature was set at 40 ℃ ， and the sample size was 5 μL. The heated electrospray ionization source was employed in the positive full mass spectra-selected ion monitoring mode. The contents of N-nitroso impurities in raw materials/formulations of 15 batches of β-blockers from 10 manufacturers were determined by this method. Discovery Studio software was applied to predict the toxicity of the impurities and estimate the attention threshold. RESULTS Among 5 kinds of β-blockers， the linear ranges of N-nitroso propranolol， N-nitroso metoprolol， N-nitroso atenolol， N-nitroso esmolol and N-nitroso bisoprolol were 1.01-503.38， 1.02-508.38， 0.97-483.63， 1.11-554.27 and 1.05-523.92 ng/mL， respectively （r＞0.999）. The limits of quantitation were 1.04， 0.25， 0.05， 0.55 and 1.05 ng/mL， and the limits of detection were 0.52， 0.08， 0.02， 0.17 and 0.52 ng/mL， respectively. RSDs of precision， reproducibility， recovery， stability and durability tests were all lower than 7.5% （n＝6 or n＝5）. Among the 15 batches of samples， except for 1 batch， N-nitroso propranolol （1.07-8.91 ng/mg）， N-nitroso metoprolol （1.43-3.37 ng/mg）， N-nitroso atenolol （1.33 ng/mg）， N-nitroso esmolol （0.19 ng/mg） and N-nitroso bisoprolol （1.27 ng/mg） were detected in all other batches. According to predictions， the above 5 impurities had varying degrees of reproductive toxicity， mutagenicity and carcinogenicity， with attention thresholds of 1.0， 0.4， 4.3， 0.2 and 46.7 ng/mg， respectively. CONCLUSIONS The established method is simple， rapid， sensitive and specific， the estimated attention thresholds are clear， which can be used for the control of N-nitroso impurities in various β-blockers.

The therapeutic effect is not ideal for patients with colorectal cancer that has already metastasized.In recent years,it has been found that extracellular vesicles play an important role in various aspects of cancer cells,and their impact on the invasion and metastasis process of colorectal cancer has gradually been revealed.This review reviews and analyzes the role of extracellular vesicles in the invasion and metastasis of colorectal cancer,and briefly introduces the role of some extracellular vesicles in the treatment of colorectal cancer.

Objective: To design the proficiency testing (PT) project (No. NIFDC-PT-183) for assays of bismuth potassium citrate capsules and organize to assess the proficiency of complexometric titration in laboratories, and provide some technical analyses and advices.
Methods: Two groups of samples with different concentration were prepared. The uniformity was evaluated with one-way analysis of variance and the stability was confirmed with t-test, whose results all conformed the requirements. The samples with three combinations were randomly distributed to 279 laboratories. The determination was performed according to the assays of bismuth potassium citrate capsules in Volume Ⅱ of the Chinese Pharmacopoeia 2015. The median value and normalized interquartile range (NIQR) of robust statistical analysis was adopted and Z-scores were used to evaluate the results from each of laboratories.
Results: Among 279 laboratories, 240 laboratories results were satisfactory, 23 were questionable, and the other 16 were unsatisfied. The satisfaction rate was 86.0%.
Conclusion: The overall capacity of national laboratories for assays of bismuth potassium citrate capsules is good while a portion of participants require further improvement.

Objective To establish a method to qualitatively identify and quantitatively determine a new impurity from beclomethasone propionate inhalation aerasol.Methods Ultra-performance liquid chromatography-Q-exactive orbitrap-mass spectrometry(UPLC-QE-MS)technology and Discovery Studio software were used to identify and predict the toxicity of a new impurity in beclomethasone propionate inhalation aerasol,and the content of this new impurity was determined by UPLC.Results The new impurity in beclomethasone propionate inhalation aerasol was polybutylene terephthalate(PBT)cyclic dimer.Discovery Studio software predicted that PBT dimer had potential developmental toxicity,with no mutagenicity,no ocular and skin irritancy and no rodent carcinogenicity.The content range of PBT dimer in 9 batches of beclomethasone propionate inhalation aerasol was 20.5-116.6 pg per bottle.Conclusion This study can realize the rapid identification and toxicity prediction of the new impurity in the preparation,and provide a theoretical basis for the quality control of the preparation by determining their content.

The network of laughter/smile production and propagation in the brain is not yet fully understood.In this paper,we report two cases of medically refractory epilepsy patients with stereotactic EEG implantation,in which smiles(without pleasurable emotions and motor awareness)and laughter(with situationally incompatible pleasurable emotions)were repeatedly induced by electrical stimulation in the left precentral gyrus,and the right insular short gyrus,respectively.This phenomenon reflects the existence of distinct and linked emotional and behavioral networks for laughter.

Objective To investigate the risk factors for postoperative pulmonary embolism in patients with spontaneous cerebral hemorrhage,and construct and verify the nomogram model.Methods A retrospective cohort study was conducted on 558 patients admitted in the First Affiliated Hospital of Chongqing Medical University and the Three Gorges Hospital Affiliated to Chongqing University.And 393 of them who hospitalized from January 2015 to January 2021 were assigned into a modeling group,and the other 165 patients from February 2021 to January 2023 into a validation group.Univariate and multivariate stepwise logistic regression analyses were used to screen out the risk factors associated with pulmonary embolism after spontaneous cerebral hemorrhage surgery.Then a nomogram model was build based on these factors and verified.Results Based on age,blood loss,Glasgow coma scale(GCS)score,surgical treatments,levels of fibrin degradation products,D-dimer and hemoglobin,plasma osmolality,and deep vein thrombosis,a risk model of pulmonary embolism was built.Receiver operating characteristic(ROC)curve analysis showed the model had good discriminability for the presence of pulmonary embolism,and the area under the curve(AUC)value was 0.908.Hosmer-Lemeshow goodness-fit test indicated that the model had a good fit to the verification set(Chi-square=14.805,df=8,P=0.063),the correction curve was close to the ideal curve,and the prediction probability of the model was close to the actual occurrence probability,suggesting the model having good accuracy.Decision curve analysis revealed that the established nomogram model can get benefits under a large range of threshold probabilities.Conclusion We develop a prediction model for postoperative pulmonary embolism in patients with spontaneous cerebral hemorrhage after surgical treatment,which shows good prediction performance in both the training and validation groups,and can be used for accurate,prompt and quick identification for the occurrence of pulmonary embolism in clinical practice.

COVID-19 is caused by a novel coronavirus-severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), which has being spreading around the world, posing a serious threat to human health and lives. Neutralizing antibodies and small molecule inhibitors for virus replication cycle are the main antiviral treatment for novel coronavirus recommended in China. To further promote the rational use of antiviral therapy in clinical practice, the National Center for Infectious Diseases (Beijing Ditan Hospital Capital Medical University and the First Affiliated Hospital, Zhejiang University School of Medicine) invited experts in fields of infectious diseases, respiratory and intensive care to develop an Expert Consensus on Antiviral Therapy of COVID-19 based on the Diagnosis and Treatment Guideline for COVID-19 ( trial version 10) and experiences in the diagnosis and treatment of COVID-19 in China. The consensus is concise, practical and highly operable, hopefully it would improve the understanding of antiviral therapy for clinicians and provide suggestions for standardized medication in treatment of COVID-19.

Objective To observe the effects on rabbit corneas and retinas after single intravitreal injection of voriconazole at different doses.Methods According to the randomization table,25 healthy rabbits were randomly divided into control group,and voriconazole 50,100,200,and 400 μg groups.Therefore,there were 5 rabbits in each group.The eyes of control group received intravitreal injection of 0.1 ml balanced saline solution,and those treatment groups received 0.1 ml voriconazole injection of corresponding dose.Before the injection and 1,7,and 14 days after the injection,endothelial cell counts and corneal thicknesses were measured;full-field electroretinogram were performed and b-wave amplitudes in maximal combined reaction (Max-R) were recorded.On 14 days after the injection,histologic structures were observed by light microscope and transmission electron microscope.Results There was no significant difference in endothelial cell counts (F=0.320,0.291,0.467,0.649) and corneal thicknesses (F=0.214,0.284,0.360,0.225) with those of control group at any time points (P＞0.05).Before and 1 day after the injection,b-wave amplitudes of each voriconazole group had no significant difference compared with those of control group (F=0.220,0.106;P＞0.05).On 7 days after the injection,b-wave amplitudes decreased significantly at doses of 200 μg and 400 μg (P＜0.05).On 14 days after the injection,there was no significant difference between the the amplitude of 200 μg group and that of control group (P＞ 0.05).However,the amplitude of the 400 μg group decreased continuously and there was still significant difference (P＜0.05).Light microscopy did not reveal any corneal abnormality in both control group and voriconazole groups.The retinas were normal except that of the 400 μg group,which had a thinner and degenerated inner nuclear layer and disordered photoreceptor layer.Under transmission electron microscope,there were no ultrastructure damages of corneas in both control group and voriconazole groups,either.The rabbit retinas of the 50 μg and 200 μg group have normal inner nuclear layer and photoreceptor layer,but degrees of changes in both layers were observed in the eyes of 200 μg and 400 μg group.Conclusions There is no obvious effects on rabbit corneas and retinas after single intravitreal injection of voriconazole at he dose less than or equal 100 μg.There are no obvious effects on rabbit corneas at the dose of 200 μg and 400 μg,while there are damages to the retinas in both functions and histological structures.

OBJECTIVE:To study the in vitro dissolution of Enalapril maleate and folic acid tablet. METHODS:HPLC was performed on the column of Agilent HC-C18 with mobile phase A of acetonitrle-phosphate buffer solution(70:30,V/V) and mobile phase B of acetonitrle-phosphate buffer solution(5:95,V/V)(gradient elution) at a flow rate of 1.0 ml/min,detection wavelength was 215 nm,column temperature was 50 ℃,and volume injection was 80 μl. Media were water,hydrochloric acid solution(pH 1.2),phosphate buffer solution(pH 5.0)and phosphate buffer solution(pH 6.8),medium volume was 900 ml and rotation speed was 50 r/min. The dissolution behavior of enalapril maleate in Enalapril maleate and folic acid tablet in 4 media were studied and compared with the dissolution behavior in vitro in original preparation of Enalapril maleate tablet,meanwhile,the dissolution behar-ior of folic acid in Enalapril maleate and folic acid tablet in phosphate buffer solution(pH 5.0)were studied and compared with dis-solution data of folic acid preparation in Japanese Orange Book to evaluate the intrinsic quality. RESULTS:The linear range was 0.561-14.03μg/ml for enalapril maleate(r=0.999 9)and 0.043-1.085μg/ml for folic acid(r=0.999 9),respectively;RSDs of pre-cision and stability tests were lower than 2.0%;recoveries of enalapril maleate in 4 media were 100.63%-102.33%(RSD=0.72%, n=9),99.27%-100.44%(RSD=0.41%,n=9),99.71%-100.29%(RSD=0.15%,n=9)and 96.74%-99.19%(RSD=0.79%,n=9),respectively. Recoveries of folic acid were 100.18%-101.63%(RSD=0.48%,n=9),97.73%-101.81%(RSD=1.32%,n=9),99.60%-102.24%(RSD=0.74%,n=9)and 100.00%-102.76%(RSD=0.90%,n=9),respectively. In 15 min,the dissolution of enalapril maleate of 2 preparations in 4 dissolution media were more than 85%;dissolution speed of folic acid in Enalapril male-ate and folic acid tablet was faster than that in folic acid preparation in phosphate buffer solution(pH 5.0). CONCLUSIONS:The method is suitable to determine the dissolution of Enalapril maleate and folic acid tablet;the in vitro dissolution curve of enalapril maleate in Enalapril maleate and folic acid tablet is similar to Renitec,and the in vitro dissolution of folic acid is better than folic acid preparation.