A practical biphasic contrast media injection protocol strongly enhances the aorta and pulmonary artery simultaneously using a single CT angiography scan.

BACKGROUND: Enhancement profiles of the pulmonary artery (PA) and aorta differ when using computed tomography (CT) angiography. Our aim was to determine the optimal CT protocol for a one-time CT scan that assesses both blood vessels. METHODS: We prospectively enrolled 101 cases of CT angiography in patients with suspected pulmonary embolism or aortic dissection from our center between 2018 and 2020. We also retrospectively collected the data of 40 patients who underwent traditional two-time CT scans between 2015 and 2018. Patients were divided into four groups: test bolus (TB) I, TB II, bolus-tracking (BT) I, and BT II. The enhancement of the PA and aorta, and the radiation doses used in the four groups were collected. Those who underwent two-time scans were classified into the traditional PA or aorta scan groups. Data were compared between the BT and traditional groups. RESULTS: The aortic enhancement was highest in BT II (294.78 ± 64.48 HU) followed BT I (285.18 ± 64.99 HU), TB II (186.58 ± 57.53 HU), and TB I (173.62 ± 69.70 HU). The radiation dose used was lowest in BT I (11.85 ± 5.55 mSv) and BT II (9.07 ± 3.44 mSv) compared with that used in the traditional groups (20.07 ± 7.78 mSv) and accounted for half of the traditional group (45.17-59.02%). The aortic enhancement was also highest in BT II (294.78 ± 64.48 HU) followed by BT I (285.18 ± 64.99 HU) when compared with that in the traditional aorta scan group (234.95 ± 94.18 HU). CONCLUSION: Our CT protocol with a BT technique allows for a lower radiation dose and better image quality of the PA and aorta than those obtained using traditional CT scans. TRIAL REGISTRATION: NCT04832633, retrospectively registered in April 2021 to the clinical trial registry.

Effects of hand placement, handles and support on manual holding tasks.

This study recruited 16 participants to examine the effects of hand placement, handles and support on the muscular activities of the musculus biceps brachii and erector spinae, box tilt angle and total center of pressure (CoP) length beneath the feet in manual holding tasks. Each participant was asked to hold a box in two hand placement conditions (symmetrical hand placement and asymmetrical hand placement) × two handle conditions (handles and no handles) × two support conditions (hands-and-body and hands). The results showed that symmetrical hand placement reduced the overall muscular activities of the musculus biceps brachii and erector spinae, box tilt angle and CoP length. The same results were also found in the handles condition and in the hands-and-body support condition. This study recommends that box designers should provide symmetrical handles, and people should keep the box against their front body while holding.

[Study on acute toxicity test of different processed products of Radix polygalae].

OBJECTIVE: To study the acute toxicity of the water extracts (ERWE) and 60% ethanol extracts (EREE) from different processed products of Radix Polygalae (crude Radix Polygalae, licorice, and honey processed Radix Polygalae), thus providing scientific evidence for toxicity study of Radix Polygalae and its safe clinical application. METHODS: The ERWE and EREE were prepared from different processed products of Radix Polygalae. Their contents of saponins were respectively determined. The poisoning condition and death of the mice administered with ERWE and EREE by gastrogavage were observed within fourteen days. The modified Karber's method was used to calculate LD50 and 95% confidence interval (CI). RESULTS: The EREE of licorice processed Radix Polygalae had the maximum toxicity with highest content of saponins, while the ERWE of honey processed Radix Polygalae had the minimum toxicity with lowest content of saponins. CONCLUSIONS: Different processing methods have effects on the contents of saponins in Radix Polygalae. The experiment showed that the toxicity of Radix Polygalae is in direct proportion to the content of saponins. The higher the saponins contents, the higher the toxicity.