The roles of primary care doctors in the COVID-19 pandemic: consistency and influencing factors of doctor's perception and actions and nominal definitions.

BACKGROUND: At the end of 2019, the Coronavirus Disease 2019 (COVID-19) pandemic broke out. As front-line health professionals, primary care doctors play a significant role in screening SARS-CoV-2 infection and transferring suspected cases. However, the performance of primary care doctors is influenced by their knowledge and role perception. A web-based cross-sectional survey was conducted to assess the consistency and influencing factors of primary care doctor's role perception and expert advice in the guidelines (regulatory definition). METHODS: We designed the questionnaire using "Wenjuanxing" platform, distributed and collected the questionnaire through WeChat social platform, and surveyed 1758 primary care doctors from 11 community health service stations, community health service centers and primary hospitals in Zhejiang Province, China. After the questionnaire was collected, descriptive statistics were made on the characteristics of participants, and univariate analysis and multivariate analysis were used to determine the relevant factors affecting their role cognition. RESULTS: In the reporting and referral suspected cases and patients receiving treatment, most participants' cognition of their roles were consistent with the requirements of guidelines. However, 49.54% and 61.43% of participant doctors were not in line with the government guidelines for diagnosing and classifying COVID-19 and treating suspected cases, respectively. Having a middle or senior professional title and participating in front-line COVID-19 prevention and control work is beneficial to the accurate role perception of diagnosis and classification of COVID-19, the reporting and transfer of suspected cases, and the treatment of suspected cases. CONCLUSIONS: Primary care doctors' role perceptions in the COVID-19 pandemic are not always consistent with government guidelines in some aspects, such as transferring and diagnosing suspected cases. Therefore, it is essential to guide primary care doctors in performing their duties, especially those with lower professional titles.

The ratio of superior mesenteric artery diameter to superior mesenteric vein diameter based on non-enhanced computed tomography in the early diagnosis of spontaneous isolated superior mesenteric artery dissection.

BACKGROUND: Spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare cause of abdominal pain. The aim of the study is to investigate the role of a new parameter, the ratio of the SMA diameter to the superior mesenteric vein (SMV) diameter (SMA/SMV) based on non-enhanced computed tomography (CT), in the early diagnosis of SISMAD. METHODS: In a registry study from December 2013 to June 2021, 97 abdominal pain SISMAD patients (SISMAD group) admitted to our hospital were enrolled. Meanwhile, the matched sex and age abdominal pain non-SISMAD patients at 1:2 were collected in reverse chronological order as the control group. Student's t-test, Wilcoxon rank-sum test, and Chi-square test were used to compare differences between the SISMAD and control groups. MedCalc was used to generate receiver operating characteristic (ROC) curve. RESULTS: A total of 291 abdominal pain patients, including 97 SISMAD patients and 194 non-SISMAD patients, were included in the current study. The maximum SMA diameter, perivascular exudation, and SMA/SMV based on non-enhanced CT were significant between the two groups (all P<0.05). ROC curves showed that for the maximum SMA diameter, the area under the curve (AUC), cut-off, sensitivity, and specificity were 0.926, 9.80, 93.8%, and 79.4%, respectively. For SMA/SMV, its AUC, cut-off, sensitivity, and specificity were 0.956, 0.83, 88.7%, and 92.3%, respectively. The diagnostic efficiency of SMA/SMV was better than that of the maximum SMA diameter (P<0.05). The combined parameters of SMA/SMV and maximum SMA diameter had the best diagnostic efficiency (AUC=0.970). CONCLUSION: SMA/SMV may be a potential marker for SISMAD.

[Mechanism of microRNA-1 regulating H9c2 cardiomyocyte apoptosis after hypoxia/reoxygenation].

OBJECTIVE: To investigate the changes of cardiomyocyte apoptosis after hypoxia/reoxygenation (H/R) regulated by microRNA-1 (miR-1). METHODS: Cardiomyocyte strain H9c2 derived from rat embryonic heart tissue were cultured in vitro. The cells in logarithmic growth phase were divided into blank control group, H/R group, miR-1 mimics+H/R group, miR-1 inhibitor antisense oligonucleotide (ASO)+H/R group and microRNA negative control fragment (miRNA NC)+H/R group. The low sugar DMEM medium containing low concentration of fetal bovine serum (FBS) was used as the medium under anoxic condition. After being cultured in a closed anaerobic incubator at 37 centigrade (95% N2 and 5% CO2) for 12 hours, the cells were cultured with the fresh high sugar DMEM medium containing 5% FBS in a closed incubator at 37 centigrade for reproducing cardiomyocyte H/R model. The blank control group was cultured in high glucose DMEM medium containing 10% FBS in 37 centigrade and 5% CO2 incubator. In miR-1 mimics+H/R group, miR-1 ASO+H/R group and miRNA NC+H/R group, the corresponding transfectants were mixed in high glucose DMEM medium and transfected into cells before H/R model was established, and the final concentration was 50 nmol/L. The blank control group and H/R group were added with DMEM medium at the same time. After the establishment of the model, the expression level of miR-1 was detected by real-time fluorescence quantitative polymerase chain reaction (qPCR). The expression levels of apoptosis-related proteins caspase-9, Bcl-2 and Bax were detected by Western blotting, and cardiomyocyte apoptosis was detected by flow cytometry. RESULTS: Compared with the blank control group, the expression levels of miR-1, caspase-9 and Bax protein and the apoptosis rate of cardiomyocytes were significantly increased, while the expression level of Bcl-2 was significantly decreased, which indicated that the expression of miR-1 and the level of apoptosis were increased in H/R group. Compared with H/R group, the expressions of miR-1, caspase-9 and Bax and the apoptosis rate of cardiomyocytes in miR-1 mimics+H/R group were further increased [miR-1 (2-ΔΔCt): 11.59±1.48 vs. 2.57±0.38, caspase-9 protein (caspase-9/ß-actin): 2.59±0.12 vs. 1.56±0.20, Bax protein (Bax/ß-actin): 4.09±0.38 vs. 1.97±0.13, apoptosis rate: (25.23±0.87)% vs. (17.86±0.73)%, all P < 0.01], while the expression of Bcl-2 was decreased (Bcl-2/ß-actin: 0.37±0.02 vs. 0.49±0.03, P < 0.01). The expressions of miR-1, caspase-9 and Bax and the apoptosis rate were significantly decreased in miR-1 ASO+H/R group [miR-1 (2-ΔΔCt): 1.16±0.06 vs. 2.57±0.38, caspase-9 protein (caspase-9/ß-actin): 1.05±0.24 vs. 1.56±0.20, Bax protein (Bax/ß-actin): 0.93±0.11 vs. 1.97±0.13, apoptosis rate: (11.19±0.85)% vs. (17.86±0.73)%, all P < 0.05], while the expression of Bcl-2 was increased (Bcl-2/ß-actin: 0.84±0.17 vs. 0.49±0.03, P < 0.05). There was no significant difference in miR-1 expression, caspase-9, Bax and Bcl-2 protein expressions, and apoptosis rate between H/R+miRNA NC group and H/R group. CONCLUSIONS: The expression of miR-1 and level of apoptosis were increased in H/R cells, and miR-1 could aggravate cardiomyocyte apoptosis.