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ObjectiveDelayed enhancement cardiac CT is a reliable tool for the diagnosis of left atrial appendage thrombus but limited for scanning heterogeneity. We aimed to explore the improvement of the 1 and 3-min delay phase at the diagnostic level to detect left atrial appendage thrombus, in order to set up a reasonable CT scanning scheme.Materials and MethodsA total of 6,524 patients were continuously retrieved from January 2015 to September 2020 retrospectively. The patients had undergone Transesophageal echocardiography (TEE) and cardiac CT with complete period include the arterial enhancement phase, 1 and 3-min delay phase, TEE were used as the reference standard. The final study included 329 patients. Three experienced radiologists independently assessed each phase of the cardiac CT images for thrombus diagnosis. We explored the improvement of the diagnostic ability of different delayed contrast-enhanced phases for left atrial appendage thrombus detection. Multiple logistic regression analysis were used for further high-risk stratification to avoid an additional 1-min delayed scan.ResultsIn total, 29 thrombosis were detected at TEE. For all cardiac CT phases, sensitivity and negative predictive were 100%. The specificity were 0.54, 0.93, and 1.00, respectively; The positive predictive values (PPV) were 0.17, 0.57, and 1.00, respectively; Area under curve (AUC) were 0.75, 0.95, and 0.98, respectively. High risk factors that cannot be clearly diagnosed with 1-min delay phase included reduced cardiac function, increased CHA2DS2-VAScscore and left atrial enlargement. Compared with the arterial enhanced phase, increased radiation doses in the 1 and 3-min delay phases were 1.7 ± 1.3 msv and 1.5 ± 0.8 msv (mean ± standard deviation).ConclusionUsing TEE as the reference standard, early contrast-enhanced CT scanning with 1 and 3-min delay is necessary for the diagnosis of left appendage thrombus, which could significantly improve the diagnostic efficiency. Patients with high-risk stratification are suitable for direct 3-min delayed scanning.

In this work, a novel and multifunctional nanocomposite of luminol capped gold modified Fe3O4 (Lu-AuNPs@Fe3O4) was utilized as the carrier of secondary antibody (Ab2) to fabricate a sandwiched electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of mucin-1 (MUC1). Herein, the luminol capped gold nanoparticles (Lu-AuNPs) were synthesized with HAuCl4 and luminol by the help of NaBH4 at room temperature, and then Lu-AuNPs were adsorbed on the Fe3O4 magnetic nanoparticles (MNPs) to form the nanocomposite of Lu-AuNPs@Fe3O4 via electrostatic interaction. Fe3O4 MNPs in Lu-AuNPs@Fe3O4 exhibited excellent conductivity and admirable catalytic activity in H2O2 decomposition, which could enhance the ECL efficiency of luminol-H2O2 system. In addition, the substrates of gold coated ZnO nanoparticles (AuNPs@ZnO), providing large specific surface areas for primary antibody (Ab1) capturing, were modified on the electrode. As a result, a wide linear range of 7 orders of magnitude from 10 fg/mL to 10 ng/mL was obtained with an ultralow detection limit of 4.5 fg/mL for MUC1.

Professor He Pu-ren, the founder of Santong method of acupuncture and moxibustion, is a well known acupuncturist at home and abroad. His main contributions include combined martial arts and Chinese medicine, showing obvious therapeutic effect; taking part in establishment of The Department of Acupuncture, Beijing Chinese Medicine Hospital; creating Santong method of acupuncture and moxibustion; advocating fire needle therapy; writing medical books and teaching students; advocating the culture of acupuncture; making the metal model of acupuncture and moxibustion, and others. His achievements have become an important part of acupuncture and moxibustion science.