ObjectiveTo explore the mechanisms of Astragali Radix-Curcumae Rhizoma （HQ-EZ） in alleviating hypercoagulability and inhibiting tumor growth and metastasis by modulating the formation of neutrophil extracellular traps （NETs） via the complement component 5a （C5a）/C5a receptor （C5aR） pathway. MethodForty male C57BL/6 mice were randomized into four groups： Blank， model， HQ-EZ （8.2 g·kg^-1）， and PMX53 （1 mg·kg^-1）. The mouse model of Lewis lung cancer was established in other three groups except the blank group. Mice were administrated with corresponding drugs from day 3 after modeling. Specifically， the HQ-EZ decoction was administrated for 14 consecutive days， while intraperitoneal injection of PMX53 was implemented on days 3， 6， 9， 12， and 15. Mouse body weight and tumor diameter were measured every two days. On the next day of the last administration， lung microCT was performed to observe the tumor metastasis in vivo. Blood samples were collected from the eyeball after anesthetization， and tumor and lungs were collected after the mice were sacrificed. Tumor weight was measured to calculate the tumor growth inhibitory rate. Enzyme-linked immunosorbent assay was employed to measure the levels of C5a， neutrophil elastase （NE）， citrullinated histone-H3 （Cit-H3）， myeloperoxidase （MPO）， matrix metallopeptidase-9 （MMP-9）， NETs， von Willebrand Factor （vWF）， tissue factor （TF）， and P-selectin in the serum and tumor tissue. Terminal-deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling was conducted to assess apoptosis in the tumor tissue. Hematoxylin-eosin staining was conducted to observe lung metastasis， and immunofluorescence （IF） was employed to observe the expression of NETs in the tumor tissue. Western blot was employed to determine the protein levels of C5aR， MPO， and Cit-H3 in the tumor tissue. ResultCompared with the blank group， the model group had nodules in the lung， increased areas with low X-ray transmittance， appearance of nodular foci and multiple hemorrhagic foci in the lungs， and darkening lung color. Furthermore， the modeling elevated the serum levels of C5a， NETs and related proteins， vWF， TF， and P-selectin （P<0.01）. Compared with the model group， HQ-EZ and PMX53 reduced the lung metastases， areas with low X-ray transmittance， and nodules in the lungs and lightened the lung color. Compared with the model group， the two drug intervention groups showed flat tumor growth curves， decreased tumor weight （P<0.01）， increased apoptosis of tumor cells （P<0.01）， lowered levels of C5a， NETs and related proteins， vWF， TF， and P-selectin both in the serum and tumor tissue （P<0.05）， and down-regulated protein levels of C5aR， MPO， and Cit-H3 （P<0.05）. ConclusionHQ-EZ inhibited the expression of NETs by suppressing the C5a/C5aR pathway， thereby alleviating hypercoagulability and inhibiting tumor growth and metastasis.

Objective:To assess the clinical application of bedside X-ray photography assistor (Patent No. 202 023 219 898.1) in neonatal bedside photography.Methods:From April 2021 to February 2022, a total of 180 pediatric patients were selected who underwent bedside chest X-ray photography in neonatal intensive care unit (NICU) of Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology. These patients were divided into contrpol group, consisting of 48 males and 42 females aged at (3.3 ± 2.0) d (0-10 d), and experimental group, including 50 males and 40 females aged (3.1±2.2) d (0-12 d). For chest photography, routine workflow was followed in the control group while in experimental group bedside photography protection and body position fixing device was used. The examination time, reshoot rate and image quality were compared between the two groups.Results:The diagnostic physician score and patient comfort score in the experimental group were higher than those in the control group, with statistically significant differences ( t = 3.98, 3.82, P < 0.001). The success rate in the experimental group was higher than that in the control group, with statistically significant difference ( χ2= 7.84, P < 0.05). The average time of examination in the experimental group was not significantly different from in the control group ( P>0.05 ). Conclusions:The application of bedside X-ray photography assistor in neonatal bedside photography can significantly improve the success rate and image quality and reduce the radiation dose to pediatric patients without significantly increased examination time, which is worthy of clinical application and promotion.

Objective:To analyze the clinical reliability of neonatal bedside photography protection and body position fixing device during neonatal bedside X-ray photography.Methods:A mobile X-ray diagnostic machine was used to project the phantom of children. The samples were divided into group A with conventional bedside photography mode, and group B using neonatal bedside X-ray photography protection device. X-ray diagnostic level dosimeters were placed at the projection and radiation sensitive sites, respectively. The three parts of the chest, pelvis and skull were used as the projection center, and the radiation dose to the projection site and the radiation sensitive site were collected and recorded, and the statistical analysis was carried out.Results:When the chest was taken as the center of the projection, the radiation doses to the lens of the eye, thyroid and gonad in the body model group B of children were 94.4%, 96.9% and 96.7% lower than those in the non-injected part of group A, respectively ( t=-152.55, -445.16, -129.07, P<0.05). When the pelvis was taken as the projection center, the radiation doses to the lens, thyroid and thymus in the body model group B were 85.5%, 87.1% and 94.9% lower than those in the non-projection part of group A, respectively ( t=-50.68, -194.18, -535.94, P<0.05). When the head was taken as the projection center, the radiation doses to thyroid, thymus and gonad in the body model group B were 99.3 %, 97.4 % and 94.3 % lower than those in the non-projection position of group A, respectively ( t=-1 859.97, -542.08, -66.26, P< 0.05). Conclusions:The use of neonatal bedside photography protection and position fixing device during neonatal bedside X-ray photography can significantly reduce the radiation dose to children in non-projected areas under the premise of ensuring image quality. At the same time, it can fix and protect the children, improve the success rate of examination, being worthy of clinical promotion.

Objective:To explore the value of monoenergetic imaging on dual-layer spectral detector CT combined with individual injection protocol of contrast medium in brain CT angiography (CTA).Methods:Seventy-six patients who underwent brain CTA on the Philips IQon dual-layer spectral detector CT and individual injection protocol of contrast medium in Union Hospital of Tongji Medical College, Huazhong University of Science and Technology from August to November 2020 were retrospectively analyzed. Objective and subjective evaluation of image quality was performed in conventional energetic images (conventional group) which derived from 120 kVp hybrid iterative reconstruction algorithm and 50 keV virtual monoenergetic images (test group) which derived from spectral reconstruction algorithm. The objective evaluation content included CT values, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of internal carotid artery and middle cerebral artery, CT values and standard deviation (SD) of brain parenchyma. The subjective evaluation was completed by two senior radiologists according to the 5-point scale, and the inter-agreement between two radiologists was evaluated by Kappa test. Paired t test or Wilcoxon rank test was used for analysis between two groups. Results:The SNR and CNR of both internal carotid artery and middle cerebral artery, as well as CT values of internal carotid artery, middle cerebral artery and brain parenchyma, were significantly higher in test group than that in conventional group (all P<0.001). The subjective scores of two radiologists for test group were both 5 (5, 5) points, and the subjective scores for conventional group were both 4 (4, 4) points. The subjective scores of the radiologists were in good agreement, and the Kappa values were 0.74 and 0.84 respectively. The subjective scores of test group were significantly higher than that of conventional group ( Z=-11.15, P<0.001). Conclusion:Monoenergetic imaging on dual-layer spectral detector CT combined with individual injection protocol of contrast medium can improve SNR, CNR and the image quality of brain CTA.

Objective:To investigate the value of the size-specific dose estimate (SSDE) on dose estimations of children's head CT scans.Methods:A retrospective study was conducted on plain head CT scans of 252 patients with the 64-row detector CT device of Discovery 750HD in the Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January to September in 2019. The volume CT dose index (CTDI vol)values were recorded. The head circumference (HC), area, and CT value were measured using a self-developed computer program, and the water equivalent diameter (WED), size-specific conversion factors ( f293 and f220), and absorbed dose (SSDE 293 and SSDE 220) were calculated according to the AAPM reports 293 and 220.The patients were divided into three groups by the quartering meth odaccording to their HC(<47.8 cm, 47.8-52.7 cm, >52.7 cm)and four groups based on their ages(0-2, 3-6, 7-10 and 11-14 years old). The difference between parameters ( f220 and f293, SSDE 220 and SSDE 293、SSDE 293 and CTDI vol) were compared for different groups, and the correlation of HC with f293 and SSDE 293 was analyzed. Results:There was an overestimation of f220 by 11.11% ( t=252.61, P<0.05) compared with f293. SSDE 220 was overestimated by 10.31% ( t=228.21, P<0.05) compared with SSDE 293, and SSDE 293 was underestimated by 9.60% ( t=-31.34, P<0.05)compared with CTDI vol. For the three HC groups, SSDE 220 was overestimated by 8.54%, 10.37%, and 11.57% ( t=73.73, 438.58, 275.52, P<0.05)compared with SSDE 293, and SSDE 293 was underestimated by 1.30%, 9.79%, and 14.61% ( t=-1.91, -60.95, -47.64, P<0.05)compared with CTDI vol. For the four age groups SSDE 220 was overestimated by 8.45%, 10.00%, 10.57%, and 11.36% ( t=63.58, 232.29, 247.84, 302.95, P< 0.05)compared with SSDE 293, and SSDE 293 was underestimated by 1.49%, 8.27%, 10.63%, and 13.78% ( t=-1.83, -28.27, -37.30, -49.80, P< 0.05)compared with CTDI vol. Furthermore, HC was highly correlated with f293 and SSDE 293 ( r2=0.88 and 0.76, respectively, P< 0.05). Conclusions:The radiation dose in children′s head CT scanning can be more accurately estimated according to the AAPM Report 293, while it can be overestimated by CTDI vol. Meanwhile, the CT radiation dose can be patently overestimated with the AAPM Report 220 compared with Report 293.HC is closely correlated with f293 and SSDE 293 and it can be used to estimatee more accurately for SSDE and the radiation dose received by children during head CT scanning.

Objective:To study the feasibility that using size-specific dose estimation (SSDE) to estimate organ dose and effective dose in coronary CT angiography (CTA).Methods:Totally 421 consecutive patients with coronary artery CTA were included and retrospectively analized. All patients were scanned using the 3rd generation dual-source Force CT with prospectively ECG gated axis scan mode. The size specific dose estimation(SSDE) for each patient was conducted by calculate water equivalent diameters with Radimetrics. The organ doses of heart, lung, liver and breast, were estimated with Monte Carlo method. Patient-specific effective dose was calculated as a weighted sum of simulated organ doses with the coefficients from ICRP 103. Linear correlation analysis was used to validate the relationship between SSDE and organ doses as well as effective dose, and to derive coefficients for patient specific dose estimation. The mean error rate was used to evaluate estimation accuracy.Results:The CTDI vol, SSDE and effective dose were (16.8±8.7)mGy, (20.8±8.8)mGy and (4.4±2.9)mSv, respectively. The linear fitting formula for estimating organ dose based on SSDE were: Y=1.2 X-6.4 ( R2=0.91, P<0.05, mean error 0.1%) for heart, Y=1.4 X-7.4 ( R2=0.91, P<0.05, mean error 7.9%) for breast, Y=0.89 X-4.6 ( R2=0.86, P<0.05, mean error 8.3%) for lung, and Y=0.36 X-1.8 ( R2=0.64, P<0.05, mean error -17.9%) for liver. The linear fitting formula for estimating the individual effective dose based on SSDE were: Y=0.21 X-1.2 ( R2=0.92, P<0.05, mean error 0.2%) for men, Y=0.39 X-2.2 ( R2=0.93, P<0.05, mean error 1.7%) for women. Conclusions:In coronary artery CTA, the absorbed dose of the organs and patient specific effective dose could be estimated with SSDE and the corresponding conversion coefficients, which will help to achieve personalized assessment and precise management of patient radiation dose and risk in clinical practice.

Objective:To investigate the clinical value of third-generation dual-source CT with high pitch, 70 kV combined with 16 ml contrast agent in low radiation dose imaging of pulmonary embolism (PE).Methods:Eighty-three patients with suspected PE underwent CT pulmonary angiography were randomly divided into two groups: group A with 36 cases, 100 kV, 1.0 pitch, and 60 ml contrast agent; group B with 47 cases, 70 kV, 2.2 pitch, and 16 ml contrast agent. The volume CT dose index and dose length product of the two groups were recorded to calculate the effective dose E, and the CT values of enhanced pulmonary arteries, background noise, and muscles values were recorded to calculate signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). The overall image quality and the beam-hardening artifact of superior vena cava were subjectively evaluated on a 3-point scale. Results:There were no significant differences in gender, age, height, weight, BMI, proportion of PE, and CT values of enhanced pulmonary arteries at all levels ( P>0.05). The value E of group B was (0.76±0.13) mSv, significantly lower than that in group A [(1.91±0.54) mSv, Z=-5.23, P<0.001]. Although background noise of group B was significantly higher than that of group A ( Z=-4.99, P <0.001), SNR and CNR values of group B were significantly lower than those of group A ( Z=-4.56, -4.48, P<0.001), there was no statistically significant difference in the overall image quality scores between the two groups ( P>0.05). The beam-hardening artifact caused by superior vena cava in group B was significantly lower than that in group A ( Z=-5.15, P <0.001). Conclusions:The third generation dual-source CT with high pitch, 70 kV combined with 16 ml contrast agent can significantly reduce the interference of contrast agent beam-hardening artifact on the right and right superior pulmonary arteries to ensure the diagnostic image quality of PE, and effectively reduce radiation dose by 60% and total volume of contrast agent by 73%.

Objective:To investigate the application value of third-generation dual-source CT(3-G DSCT) low-dose scan mode combined with iterative reconstruction technology in the screening of COVID-19 and to evaluate the radiation dose.Methods:One hundred and twenty patients suspected of COVID-19 from December 2019 to February 2020 were retrospectively analysed and randomly divided into two groups (test group and conventional group, 60 patients in each). The parameters for test group included 3-G DSCT, Turbo Flash scan mode, CARE kV, with reference 90 kV, pitch 2.0, and ADMIRE algorithm, while those parameters for conventional group included the 128-slice CT, conventional spiral scan mode, 120 kV, pitch 1.2, and FBP algorithm. The CT values of aorta, spinal posterior muscle, and subcutaneous fat, the aortic noise, signal-to-noise ratio (SNR), and contrast noise ratio (CNR) were compared to evaluate the image quality between two groups. Two experienced doctors scored the image quality using a double-blind method, and compared the CT dose index volume (CTDI vol), dose-length product (DLP), and effective dose ( E) of the two groups. Results:The CT value of the aorta and spinal posterior muscle and the aortic SNR in the test group were (45.38±4.77), (53.41±8.44) HU, and 2.82±0.59, and significantly higher than those in the conventional group [(39.68±6.26), (42.66±6.32) HU, 2.58±0.61, t=5.608, 7.897, 2.162, P<0.05]. The aortic noise, CNR and subjective scores between the two groups had no significant difference( P>0.05). The CTDI vol, DLP, and E in the test group were (3.09±1.02) mGy, (107.57±32.81) mGy·cm, (1.51±0.46) mSv, significantly lower than those in the conventional group [(7.00±1.80) mGy, (261.65±73.93) mGy·cm, (3.66±1.03) mSv; t=-14.680, -14.756, -14.756, P<0.05]. Conclusions:In the screening of COVID-19, using low-dose scanning mode of 3-G DSCT combined with iterative reconstruction technology would provide diagnostic quality images and meanwhile effectively reduce the radiation dose and improve the SNR of the image.

Objective:To explore a low dose CT scanning method on novel coronavirus (COVID-19) pneumonia based on infection prevention and control.Methods:A total of 140 patients with confirmed novel coronavirus pneumonia in Xiehe hospital from January 20, 2020 to February 28, 2020 were undertaken CT scan and divided into low dose group and conventional dose group. The patients in low dose group(120 kV, 31 mAs) consisted of mild type(51), severe type(15) and critically ill type(4); and those in conventional dose group(120 kv, adaptive milliampere second) consisted of mild type(48), severe type(17) and critically ill type(5). The effective radiation dose, SNR and CNR of CT scan were compared between two groups. A senior and a middle radiologist made the image subjective quality scores, respectively.Results:The effective dose in low dose group was lower than that of conventional dose group( t=-48.343, P<0.05). There was no significant difference in SNR and CNR between two groups( P>0.05). For severe and critically ill patients, the score in low dose group was significantly lower than that in conventional dose group( t=-2.781, P<0.05). There was no significant difference in scores between two groups for mild patients( P>0.05). Conclusions:Low-dose CT scanning could meet the image quality needs for patients with COVID-19 and meanwhile significantly reduce the radiation dose.

Since February 9th, 2020, the mobile CT in Jianghan mobile cabin hospital had begun to be used for scanning patients with COVID-19.The mobile CT has played an irreplaceable role in clinical diagnosis with its unique advantages. During CT scanning, the technicians should not only ensure that the patients receive the radiation dose as low as possible, but also be aware of the importance of the infection prevention and control. Meanwhile, we need concern the technicians about the psychological problems and should take effective action when they occured.