Risk factors analysis and intervention of blood-borne occupational exposure in medical staff / 中华劳动卫生职业病杂志

Objective: To analyze the risk factors of blood-borne occupational exposure among medical staff and explore the relevant intervention measures. Methods: In June 2020, the data of blood-borne occupational exposure and related factors reported by medical staff in a grade Ⅲ, Grade A general hospital from 2011 to 2019 were analyzed by retrospective investigation. Results: Among 431 cases of blood-borne occupational exposure, 69.37% were nurses. It mainly occurred in medical staff with 0-4 years of service, accounting for 63.57%; The main place of occupational exposure was in the ward 47.56%; Sharp instrument injury was the main occupational exposure route 91.65%. Occupational exposure department was mainly surgery department 17.87%; The main source of exposure was hepatitis B virus (HBV) 37.12%, followed by treponema pallidum 20.19%. Statistical analysis results show that: Exposure sites (χ(2)=43.585, P<0.01) , exposure sources (χ(2)=22.693, P<0.01) , treatment methods after exposure (χ(2)=18.866, P<0.01) , Flushing (χ(2)=31.963, P<0.01) and disinfection (χ(2)=14.216, P<0.01) were significantly different. Conclusion: The effective measures to reduce blood-borne occupational exposure are to strengthen occupational protection training of medical staff, standardize operation procedures, strengthen supervision of key groups and departments, improve reporting, monitoring and follow-up systems to realize informatization, and do a good job in risk control.

Development and validation of a deep learning model to screen hypokalemia from electrocardiogram in emergency patients / 中华医学杂志(英文版)

BACKGROUND@#A deep learning model (DLM) that enables non-invasive hypokalemia screening from an electrocardiogram (ECG) may improve the detection of this life-threatening condition. This study aimed to develop and evaluate the performance of a DLM for the detection of hypokalemia from the ECGs of emergency patients.@*METHODS@#We used a total of 9908 ECG data from emergency patients who were admitted at the Second Affiliated Hospital of Nanchang University, Jiangxi, China, from September 2017 to October 2020. The DLM was trained using 12 ECG leads (lead I, II, III, aVR, aVL, aVF, and V1-6) to detect patients with serum potassium concentrations <3.5 mmol/L and was validated using retrospective data from the Jiangling branch of the Second Affiliated Hospital of Nanchang University. The blood draw was completed within 10 min before and after the ECG examination, and there was no new or ongoing infusion during this period.@*RESULTS@#We used 6904 ECGs and 1726 ECGs as development and internal validation data sets, respectively. In addition, 1278 ECGs from the Jiangling branch of the Second Affiliated Hospital of Nanchang University were used as external validation data sets. Using 12 ECG leads (leads I, II, III, aVR, aVL, aVF, and V1-6), the area under the receiver operating characteristic curve (AUC) of the DLM was 0.80 (95% confidence interval [CI]: 0.77-0.82) for the internal validation data set. Using an optimal operating point yielded a sensitivity of 71.4% and a specificity of 77.1%. Using the same 12 ECG leads, the external validation data set resulted in an AUC for the DLM of 0.77 (95% CI: 0.75-0.79). Using an optimal operating point yielded a sensitivity of 70.0% and a specificity of 69.1%.@*CONCLUSIONS@#In this study, using 12 ECG leads, a DLM detected hypokalemia in emergency patients with an AUC of 0.77 to 0.80. Artificial intelligence could be used to analyze an ECG to quickly screen for hypokalemia.

Efficacy and safety of non-vitamin K antagonist versus vitamin K antagonist oral anticoagulants in the prevention and treatment of thrombotic disease in active cancer patients: a systematic review and meta-analysis of randomized controlled trials / 中华心血管病杂志

Object We aimed to compare the efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOAC) and vitamin K antagonist (VKA) in the prevention and treatment of thrombotic diseases in patients with active cancer. Methods: To find randomized controlled trials (RCT) in which NOACs were compared VKAs in active cancer, we searched the electronic databases (PubMed, Web of Science and Clinical Trials) up to May 2019 and and languages restricted to Chinese and English. According to the screening strategy, two researchers independently screened and extracted literature, evaluated the quality of literature, the suitability of collected cross study data for analysis, and tested the heterogeneity. The relative risk (RR) and 95% confidence interval (95%CI) of major bleeding, clinically related non-major bleeding, VTE, stroke and all-cause mortality in active cancer patients with VTE, active cancer patients with non-valvular atrial fibrillation (NVAF) was calculated and the results were compared between NOAC with VKA. Results: A total of 9 RCTs were included, including 5 cancers with VTE (5/9) and 4 cancers with NVAF (4/9). A total of 5 867 patients were included. After excluding 1 818 (30.99%) patients with cancer history, 4 049 (68.86%) patients with active cancer were statistically analyzed. Among them, 2 278 (56.26%) received NOAC treatment, 1 771 patients (43.74%) received VKA treatment. The quality of the included documents was high (all scores were>5 points), and the data of each included document could be summarized and analyzed (P>0.05). The heterogeneity of main outcome events was very low (I2 = 0). In VTE patients with active cancer, NOACs were more effective in reducing recurrence of VTE （RR=0.55, 95%CI 0.36 -0.84; P = 0.005) and clinically related non-major bleeding (RR=0.77, 95%CI 0.60 -0.98; P = 0.03) than VKAs. In NVAF patients with active cancer, efficacy of NOACs and VKAs was similar in terms of reducing VTE, stroke, clinically related non-major bleeding, major bleeding and all-cause mortality events (P>0.05). Conclusions: For patients with active cancer accompanied by VTE, NOAC may has more advantages in efficacy and safety compared to VKA in the prevention and treatment of thrombotic diseases.

Purification and characterization of glutamate dehydrogenase. from Corynebacterium glutamicum S9114 / 生物工程学报

Glutamate dehydrogenase (GDH) is a key enzyme in the biosynthesis of glutamate. The GDHs from Corynebacterium glutamicum S9114 the most commonly used strain in glutamate fermentation, were purified and their molecular structures and properties characterized. The coenzymes were also studied in the hope to increase glutamate production. Cells were harvested at mid-exponential phase by centrifugation and washed with Tris-HCl buffer containing DTT and EDTA (pH 7.5). The cells were then disrupted using a French pressure cell press and the supernatant was collected by centrifugation. The extract was concentrated by 70-fold using the AKTA-100 FPLC system employing a DEAE-cellulose ion exchange column, a hydrophobic interaction chromatography (HIC) and Sephadex G-200 gel filtration. The purified extracts contained NADPH-dependent GDH and NADH-dependent GDH. Both of the enzymes were highly specific for the coenzymes. The molecular masses of the NADPH-dependent GDH and its subunit were 188kD and 32kD respectively, suggesting the enzyme is a homo-hexamer. Our data reported for the first time the presence of NADH- dependent GDH in Corynebacterium glutamicum S9114, similar to other microorganisms containing both GDHs. The NADPH-dependent and NADH-dependent GDH in Corynebacterium glutamicum S9114 may participate in the assimilation and dissimilation of ammonia respectively. The absorptions of NADPH-dependent GDH was very weak at 280nm but very high at 215nm, suggesting a low phenylalanine and tyrosine content in the enzyme.

Advances in the Research on Microbial Phytases / 微生物学通报

Phytases are studied widely in plants and microorganisms. Interest in these enzymes has been stimulated by the fact that phytase has the advantage in forage, food process and medicine. This paper reviews recent trends on the production, purification, properties and gene of microbial phytases.