Background::Acute pulmonary embolism (APE) is a fatal cardiovascular disease, yet missed diagnosis and misdiagnosis often occur due to non-specific symptoms and signs. A simple, objective technique will help clinicians make a quick and precise diagnosis. In population studies, machine learning (ML) plays a critical role in characterizing cardiovascular risks, predicting outcomes, and identifying biomarkers. This work sought to develop an ML model for helping APE diagnosis and compare it against current clinical probability assessment models.Methods::This is a single-center retrospective study. Patients with suspected APE were continuously enrolled and randomly divided into two groups including training and testing sets. A total of 8 ML models, including random forest (RF), Na?ve Bayes, decision tree, K-nearest neighbors, logistic regression, multi-layer perceptron, support vector machine, and gradient boosting decision tree were developed based on the training set to diagnose APE. Thereafter, the model with the best diagnostic performance was selected and evaluated against the current clinical assessment strategies, including the Wells score, revised Geneva score, and Years algorithm. Eventually, the ML model was internally validated to assess the diagnostic performance using receiver operating characteristic (ROC) analysis.Results::The ML models were constructed using eight clinical features, including D-dimer, cardiac troponin T (cTNT), arterial oxygen saturation, heart rate, chest pain, lower limb pain, hemoptysis, and chronic heart failure. Among eight ML models, the RF model achieved the best performance with the highest area under the curve (AUC) (AUC = 0.774). Compared to the current clinical assessment strategies, the RF model outperformed the Wells score ( P = 0.030) and was not inferior to any other clinical probability assessment strategy. The AUC of the RF model for diagnosing APE onset in internal validation set was 0.726. Conclusions::Based on RF algorithm, a novel prediction model was finally constructed for APE diagnosis. When compared to the current clinical assessment strategies, the RF model achieved better diagnostic efficacy and accuracy. Therefore, the ML algorithm can be a useful tool in assisting with the diagnosis of APE.

Objective:To investigate the values of two-dimensional and three-dimensional echocardiographic parameters in predicting pulmonary vascular resistance (PVR) in chronic pulmonary thromboembolic pulmonary hypertension (CTEPH).Methods:A total of 141 patients diagnosed with CTEPH in China-Japan Friendship Hospital from November 2015 to December 2022 were included. Two-dimensional echocardiographic indicators reflecting PVR were constructed according to the calculation formula of PVR: echocardiographic estimated systolic pulmonary artery pressure (sPAP Echo)/left ventricular end-diastolic diameter (LVIDd), echocardiographic estimated mean pulmonary artery pressure (mPAP Echo)/LVIDd. sPAP Echo/left ventricular end-diastolic volume (LVEDV), sPAP Echo/left ventricular cardiac output (LVCO) were measured by three-dimensional echocardiography. The correlations between two-dimensional and three-dimensional echocardiographic ratios and invasive PVR were then analyzed using the Spearman correlation method. Using receiver operating characteristic curve analysis, cut-off values for the ratios were generated to identify patients with PVR>1 000 dyn·s -1·cm -5. Pre- and postoperative hemodynamics and echocardiographic data were analyzed, as well as the correlation between the reduction rate of the echocardiographic index and PVR in 54 patients who underwent pulmonary endarterectomy (PEA). Results:sPAP Echo/LVIDd, sPAP Echo/LVEDV and sPAP Echo/LVCO were moderately correlated with PVR( rs=0.62, 0.52, 0.63, both P<0.001). The ratio of sPAP Echo to LVEDV, when greater than or equal to 1.41, had a sensitivity of 0.800 and a specificity of 0.930 for determining PVR >1 000 dyn·s -1·cm -5 (AUC=0.860, P<0.001). Similarly, the ratio of sPAP Echo to LVIDd, when greater than or equal to 2.14, had a sensitivity of 0.647 and a specificity of 0.861 for determining PVR >1000 dyn·s -1·cm -5 (AUC=0.830, P<0.001). The sPAP Echo/LVIDd and mPAP Echo/LVIDd significantly decreased after PEA (both P<0.001). The sPAP Echo/LVIDd and mPAP Echo/LVIDd reduction rate (ΔsPAP Echo/LVIDd and ΔmPAP Echo/LVIDd) were significantly correlated with PVR reduction rate (ΔPVR), respectively ( rs=0.61, 0.63, both P<0.05). Conclusions:Two-dimensional ratio sPAP Echo/LVIDd and three-dimensional ratio sPAP Echo/LVEDV can be used to noninvasively estimate PVR in CTEPH patients. The conventional ratio sPAP Echo/LVIDd is convenient and reproducibly suitable for monitoring the improvement of PVR before and after treatment, and its ratio of 2.14 can predict the significant increase of PVR in CTEPH patients (>1 000 dyn·s -1·cm -5).

Objective:To investigate the safety and efficacy of balloon pulmonary angioplasty (BPA) for residual pulmonary hypertension (PH) of chronic thromboembolic pulmonary hypertension(CTEPH) after pulmonary endarterectomy (PEA).Methods:Patients diagnosed as PH after PEA in China-Japan Friendship Hospital from Oct 2016 to Jun 2022 were included. The indication for BPA was decided on the basis of a consensus of the multi-disciplinary team for all patients with CTEPH. Before treatment, the patient′s exercise tolerance and pulmonary artery flow parameters were evaluated. A comparative analysis of various parameters before BPA treatment and at the last BPA was conducted. 6-min walk distance (6MWD) was analyzed using the paired Wilcoxon test; N-terminal pro-brain natriuretic peptide (NT-proBNP), mixed venous oxygen saturation, mean pulmonary arterial pressure (mPAP), cardiac index (CI) and pulmonary vascular resistance (PVR) were compared using the paired-samples t-test. WHO functional class was compared using McNemar′s test. Results:Twenty patients with a total of 130 vessels underwent 46 sessions of BPA treatment. The postoperative 6-minute walk distance (6MWD) [447 (415, 485) m] showed a significant improvement compared to the preoperative baseline [389 (335, 470) m] ( Z=6.52, P<0.05), Postoperative mixed venous oxygen saturation (72.0%±1.9%) showed a significant improvement compared to the preoperative levels (64.0%±2.7%) ( t=2.14, P<0.05).Postoperatively, plasma NT-proBNP [(351.9±129.9) pg/ml], mPAP [(24.2±1.9) mmHg], and PVR [(3.0±1.4) WU] significantly decreased compared to preoperative levels [(982.5±426.2) pg/ml, (33±2.1) mmHg, (8.0±1.6) WU)] ( t=3.38, 1.22, 2.10, P<0.05 for all). Postoperatively, there was a significant improvement in WHO functional class (Ⅰ，Ⅱ，Ⅲ，Ⅳ: 14, 4, 2, 0 cases) compared to preoperative status (Ⅰ，Ⅱ，Ⅲ，Ⅳ: 0, 13, 5, 2 cases) ( χ2=20.17, P<0.05). Four cases of pulmonary artery dissection and one episode of hemoptysis occurred postoperatively, with no other complications reported. Conclusions:BPA can significantly improve exercise tolerance and hemodynamic parameters for residual PH after PEA. BPA is a relatively safe and effective treatment for residual PH after PEA.

Objective:To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023.Methods:The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed.Results:A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M ( Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant ( P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age ( P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion:Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

Objective:To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023.Methods:The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed.Results:A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M ( Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant ( P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age ( P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion:Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

Objective:To assess the configuration and systolic function of the left ventricle in patients with chronic thromboembolic pulmonary hypertension (CTEPH) by routine ultrasound, two-dimensional speckle tracking imaging and three-dimensional echocardiography, and to observe the recovery after pulmonary endarterectomy (PEA).Methods:The patients who were diagnosed with CTEPH, underwent PEA and had no left heart disease were enrolled as the CTEPH group ( n=30) in the China-Japan Friendship Hospital from November 2016 and June 2021. The right heart catheterization data before and after surgery were recorded. In the meantime, gender- and age-matched healthy individuals who sought for physical examination during the same period were included as the control group ( n=23). Echocardiography findings before and after PEA were comparatively analyzed and compared between the two groups, including left ventricular end-diastolic diameter (LVEDd), right and left ventricular cross-section ratio (RVd/LVd), left ventricular global longitudinal strain (LVGLS), left ventricular end-diastolic/systolic volume index (LVEDVi/LVESVi), left ventricular ejection fraction (LVEF) and left ventricular stroke volume (LVSV). Associations between the mean pulmonary arterial pressure (mPAP)/pulmonary vascular resistance (PVR) and left ventricular function were discussed. Results:When compared with the control group, the LVEDd, LVEDVi, LVESVi, LVSV, LVGLS and the mitral early to late diastolic flow velocity ratio (E/A) in the CTEPH group were lower (all P<0.05). There were no significant differences between the two groups regarding LVEF, cardiac output (CO), and cardiac index (CI) (all P>0.05). There were no statistical differences of the left ventricular volume and LVSV between PEA group and the control group (both P>0.05), while the LVGLS and E/A remained lower (both P<0.05). Correlation analysis showed negative associations between mPAP and LVSV as well as E/A ( r=-0.490, -0.455; both P<0.05). Conclusions:There are changes in left ventricular configuration with abnormal filling pattern and potential systolic dysfunction in CTEPH patients. The PEA surgery could lead to recovery of the left ventricular configuration and volume, but the filling pattern and LVGLS at follow-up can not recover completely.

New threats posed by the emerging circulating variants of SARS-CoV-2 highlight the need to find conserved neutralizing epitopes for therapeutic antibodies and efficient vaccine design. Here, we identified a receptor-binding domain (RBD)-binding antibody, XG014, which potently neutralizes β-coronavirus lineage B (β-CoV-B), including SARS-CoV-2, its circulating variants, SARS-CoV and bat SARSr-CoV WIV1. Interestingly, antibody family members competing with XG014 binding show reduced levels of cross-reactivity and induce antibody-dependent SARS-CoV-2 spike (S) protein-mediated cell-cell fusion, suggesting a unique mode of recognition by XG014. Structural analyses reveal that XG014 recognizes a conserved epitope outside the ACE2 binding site and completely locks RBD in the non-functional "down" conformation, while its family member XG005 directly competes with ACE2 binding and position the RBD "up". Single administration of XG014 is effective in protection against and therapy of SARS-CoV-2 infection in vivo. Our findings suggest the potential to develop XG014 as pan-β-CoV-B therapeutics and the importance of the XG014 conserved antigenic epitope for designing broadly protective vaccines against β-CoV-B and newly emerging SARS-CoV-2 variants of concern.
Angiotensin-Converting Enzyme 2 ; Antibodies, Neutralizing ; Antibodies, Viral ; COVID-19 ; Epitopes ; Humans ; SARS-CoV-2/genetics* ; Spike Glycoprotein, Coronavirus/genetics*

Objective:To understand the common viral infection among the surveillance cases of fever respiratory syndrome (FRS) in nine provinces in China.Methods:The research data were obtained from nine provinces (Anhui, Beijing, Guangdong, Hebei, Hunan, Jilin, Shandong, Shaanxi and Xinjiang) in the "Infectious Disease Surveillance Technology Platform Information Management System" of the Chinese Center for Disease Control and Prevention from January 2009 to June 2021. Finally, 8 243 FRS cases with nucleic acid detection results of eight viruses [human influenza virus (HIFV), human respiratory syncytial virus (HRSV), human adenovirus (HAdV), human parainfluenza virus (HPIV), human rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV) and human Boca virus (HBoV)] were included in the study. The χ 2 test/Fisher exact probability method was used to analyze the difference of virus detection rate in different age groups, regions and seasons. Results The M ( Q1, Q3) age of 8 243 FRS cases was 4 (1, 18) years old, and 56.56% (4 662 cases) were children under 5 years old. Males accounted for 58.1% (4 792 cases) of all cases. All cases were from outpatient/emergency department (2 043 cases) and inpatient department (6 200 cases). The virus detection rates of FRS cases from high to low were HRSV, HIFV, HPIV, HRV, HAdV, HMPV, HCoV and HBoV. Two or more viruses were detected simultaneously in 524 cases, accounting for 15.66% of virus-positive cases. The difference of the virus detection rate in different age groups was statistically significant (all P values<0.05), and the virus detection rate in children<5 years old was higher (49.96%). The positive rate of any virus in south China was higher than that in north China ( P<0.001). The virus-positive FRS cases were detected throughout the year. The detection rate of HRSV was higher in autumn and winter. The detection rate of HIFV was higher in winter. The detection rate of HMPV was higher in winter and spring. The detection rates of HPIV, HRV, HCoV and HBoV were higher in summer and autumn, while there was no significant difference in the detection rate of HAdV in different seasons. Compared with 2009-2019, the detection rate of any virus in 2020-2021 decreased from 41.37% to 37.86%. The detection rate of HIFV decreased sharply from 10.62% to 1.37%. The detection rate of HPIV decreased from 8.24% to 5.88%. The detection rate of HRV and HBoV increased from 5.43% and 1.79% to 9.67% and 3.19%, respectively. Conclusion:HRSV and HIFV infections are more common among FRS cases in nine provinces in China from 2009 to 2021, and the epidemiological characteristics of eight common respiratory viruses vary in different age groups, regions and seasons.

Objective:To understand the common viral infection among the surveillance cases of fever respiratory syndrome (FRS) in nine provinces in China.Methods:The research data were obtained from nine provinces (Anhui, Beijing, Guangdong, Hebei, Hunan, Jilin, Shandong, Shaanxi and Xinjiang) in the "Infectious Disease Surveillance Technology Platform Information Management System" of the Chinese Center for Disease Control and Prevention from January 2009 to June 2021. Finally, 8 243 FRS cases with nucleic acid detection results of eight viruses [human influenza virus (HIFV), human respiratory syncytial virus (HRSV), human adenovirus (HAdV), human parainfluenza virus (HPIV), human rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV) and human Boca virus (HBoV)] were included in the study. The χ 2 test/Fisher exact probability method was used to analyze the difference of virus detection rate in different age groups, regions and seasons. Results The M ( Q1, Q3) age of 8 243 FRS cases was 4 (1, 18) years old, and 56.56% (4 662 cases) were children under 5 years old. Males accounted for 58.1% (4 792 cases) of all cases. All cases were from outpatient/emergency department (2 043 cases) and inpatient department (6 200 cases). The virus detection rates of FRS cases from high to low were HRSV, HIFV, HPIV, HRV, HAdV, HMPV, HCoV and HBoV. Two or more viruses were detected simultaneously in 524 cases, accounting for 15.66% of virus-positive cases. The difference of the virus detection rate in different age groups was statistically significant (all P values<0.05), and the virus detection rate in children<5 years old was higher (49.96%). The positive rate of any virus in south China was higher than that in north China ( P<0.001). The virus-positive FRS cases were detected throughout the year. The detection rate of HRSV was higher in autumn and winter. The detection rate of HIFV was higher in winter. The detection rate of HMPV was higher in winter and spring. The detection rates of HPIV, HRV, HCoV and HBoV were higher in summer and autumn, while there was no significant difference in the detection rate of HAdV in different seasons. Compared with 2009-2019, the detection rate of any virus in 2020-2021 decreased from 41.37% to 37.86%. The detection rate of HIFV decreased sharply from 10.62% to 1.37%. The detection rate of HPIV decreased from 8.24% to 5.88%. The detection rate of HRV and HBoV increased from 5.43% and 1.79% to 9.67% and 3.19%, respectively. Conclusion:HRSV and HIFV infections are more common among FRS cases in nine provinces in China from 2009 to 2021, and the epidemiological characteristics of eight common respiratory viruses vary in different age groups, regions and seasons.

Objective:To clarify the infection and epidemic characteristics of the human metapneumovirus (HMPV) in Chinese patients with febrile respiratory syndrome (FRS), and to provide important baseline data for clinical diagnosis, treatment, prevention and control of HMPV-induced respiratory tract diseases in China.Methods:FRS cases from January 2009 to June 2021 in 9 provinces in China, including Beijing, Hebei, Jilin, Shandong, Shaanxi, Xinjiang, Anhui, Guangdong, Hunan were retrospectively analyzed for their respiratory samples, clinical and epidemic data.The respiratory samples were detected for HMPV by quantitative real-time PCR.Results:A total of 11 660 cases were tested for HMPV, involving 296 (2.54%) HMPV-positive cases.Among 296 HMPV-positive cases, 218 were single HMPV infection, and 78/296 (26.35%) were co-infected with one or more respiratory viruses.HMPV mainly affected children under 5 years of age (3.10%), and in this population, the proportion of pneumonia in HMPV co-infection cases was significantly higher than that of single HMPV infection.HMPV could be detected all year round, which was more popular in winter and spring, with the peak of HMPV epidemic in March.Conclusions:HMPV is one of the important pathogens causing acute respiratory infection in children, showing a clear seasonal epidemic.HMPV can be infected alone or in combination with other respiratory viruses, which may increase the risk of pneumonia in children.