Objective To investigate the effect of different noise index (NI) combined with iterative recombination on the image quality and radiation dose of CT scan in patients with different body mass index (BMI). Method One hundred and sixty patients who had a liver CT enhanced scan were divided into group A (18 kg/m2≤BMI<24 kg/m2 ) and group B (24 kg/m2≤BMI<31 kg/m2) according to BMI, and each group had 80 patients. The two groups were randomly divided into 4 subgroups which NI value was 11, 13, 15 and 17 respectively. All images were restructured with 50% adaptive statistical iterative reconstruction. Subjective evaluation, objective evaluation [signal noise ratio (SNR) and contrast noise ratio (CNR)] and the effective dose of each group were recorded and calculated after the scan. ANOVA and Kruskal-Wallis test were used to evaluated the difference of imaging quality and radiation dose. Results In group A, the SNR, CNR and the subjective score of the later arterial phase images showed a statistical difference between NI=17 group and other subgroups (P<0.05), while there was no statistical differences among the other three subgroups during three CT enhanced phase. The average ED of NI=15, 17 group were decreased by 57.56%(2.17/3.77) and 61.54% (2.32/3.77) compared with NI=11 group, respectively. In group B, the SNR, CNR and the subjective image scores of the later arterial phase showed a significant difference between NI=15 and NI=11, 13 group (P<0.05). There was a statistically difference of image quality in group NI=17 compared with the other three subgroups in the later arterial phase, portal venous phase and equilibrium phase (P<0.05). The average ED of NI= 13, 15 group was decreased by 26.41% (1.69/6.40) and 45.31%(2.90/6.40) compared with NI=11 group, respectively. Conclusion Upon maintaining diagnostic imaging quality, setting different NI according to BMI and applying the iterative reconstruction algorithm can effectively reduce the radiation dose of liver CT enhanced scanning.

Objective To investigate the best weighting of adaptive statistical iterative reconstruction (ASIR) algorithm and optimized low-dose scanning parameters in thoracic aorta CT angiography(CTA).Methods Totally 120 patients with the body mass index (BMI) of 19-24 were randomly divided into 6 groups.All patients underwent thoracic aorta CTA with a GE Discovery CT 750 HD scanner (ranging from 290-330 mm).The default parameters (100 kV,240 mAs) were applied in Group 1.Reconstructions were performed with different weightings of ASIR (10％-100％ with 10％),and the signal to noise ratio (S/N) and contrast to noise ratio (C/N) of images were calculated.The images of series were evaluated by 2 independent radiologists with 5-point-scale and lastly the best weighting were revealed.Then the mAs in Group 2-6 were defined as 210,180,150,120 and 90 with the kilovoltage 100.The CTDIvoland DLP in every scan series were recorded and the effective dose (E) was calculated.The S/N and C/N were calculated and the image quality was assessed by two radiologists.Results The best weighing of ASIR was 60％ at the 100 kV,240 mAs.Under 60％ of ASIR and 100 kV,the scores of image quality from 240 mAs to 90 mAs were(4.78 ±0.30)-(3.15 ±0.23).The CTDIvol and DLP were 12.64-4.41 mGy and 331.81-128.27 mGy,and the E was 4.98-1.92 mSv.The image qualities among Group 1-5 were nor significantly different (F =5.365,P ＞ 0.05),but the CTDIvol and DLP of Group 5 were reduced by 37.0％ and 36.9％,respectively compared with Group 1.Conclusions In thoracic aorta CT Angiography,the best weighting of ASIR is 60％,and 120 mAs is the best mAs with 100 kV in patients with BMI 19-24.

Objective To investigate the image quality,radiation dose and iodine intake of CT pulmonary angiography (CTPA) in patients using low tube voltage (100 kVp) combination of different noise indexes (NI) and low concentration contrast agent.Methods A total of 80 patients with suspected pulmonary embolism (PE) and other pulmonary diseases who had undergone CTPA were divided into four groups (A,B,C and D),with 20 patients in each group.Group A underwent 120 kVp CT scan protocol in combination with NI=25 and 370 mg iodine/ml contrast agent,while groups B,C and D underwent 100 kVp CT scan protocol in combination with NI=30,35,40,and 320 mg iodine/ml contrast agent,respectively.All images were restructured using 60％ adaptive statistical iterative algorithm 2.0.Objective image quality evaluation included CT values of pulmonary artery,noise values of pulmonary artery,signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR).Subjective image evaluation used a 5-point scoring method and was conducted by two independent radiologists.The CT dose index of volume (CTDIvol),dose-length product (DLP) and iodine intake was recorded,and the mean value was calculated.The DLP was converted to the effective dose (ED).Analysis of Variance or Kruskal-Wallis test was used to evaluate the differences among the four groups in terms of image quality,radiation dose and iodine intake.Results There was a significant difference in CT values of pulmonary artery among the groups A,B,C and D (P＜0.05),and the CT values of pulmonary artery of group A was the lowest.There was no significant differences in noises of pulmonary artery,SNR,CNR and subjective indexes scores among the groups A,B,C and D (P＞0.05).There was a significant difference in iodine intake among the groups A,B,C and D,iodine intake of the group A was the highest,iodine intake of the group D was the lowest.The iodine intake of groups B,C and D decreased by 12.4％ (42/340),13.2％ (45/340) and 15.0％ (51/340) relative to group A,respectively.There was a significant difference in radiation dose among the groups A,B,C and D,The CTDIvol,DLP and ED of group D decreased by 45.3％ (3.9/8.6),48.6％ (120/247) and 48.3％ (2.02/4.18) relative to group A,respectively (P＜0.01).Conclusion Low tube voltage combination with high NI value and low concentration contrast agent can more effectively reduce the radiation dose and iodine intake for CTPA while maintaining diagnostic image quality.

Objective To compare the image quality and radiation dose of CTA of the kidney in patients using routine CT and the spectral imaging combination of different scanning protocols with the adaptive statistical iterative reconstruction 2.0 algorithm (ASIR 2.0). Methods A total of 90 patients who had undergone a CTA of the kidney were divided into three groups (A, B and C), with 30 patients in each group. Group A underwent a routine CT examination, and the scan parameters are:120 kVp, 30 to 650 mA, rotation time 0.5 s/r, scan FOV 50 cm × 50 cm;while groups B and C underwent spectral imaging protocol 1 and 2, the scan parameters of spectral imaging protocol 1 and 2 are:rapid dual kVp (80-140 kVp) switching in 0.25 ms, 375 mA and 360 mA, rotation time 0.7 s/r and 0.6 s/r, scan FOV 36 cm × 36 cm and 32 cm × 32 cm, respectively. All images were reconstructured using ASIR 2.0. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of all images were calculated when the kidney CTA was completed. Each subjective image evaluation used a 5-point scoring method and was conducted by two independent radiologists. The CT dose index (CTDIvol) and dose-length product (DLP) were recorded, and the mean value was calculated. The DLP was converted to the effective dose (ED). All data were compared with Kruskal-Wallis test and one-way ANOVA. Results The energy level of 49 to 56 keV was found to provide the best CNR for displaying CTA of the kidney. There were significant differences in CT values, noise, SNR, CNR and subjective score between groups B, C and A (P<0.05), and there was no significant differences in CT values, noise, SNR, CNR and subjective score between groups B and C (P>0.05). There were significant differences in ED among groups A, B and C (P<0.05), and the ED of groups A, B and C were (8.2±1.2), (5.2± 0.9) and (4.4 ± 0.7) mSv, respectively. Conclusion Spectral imaging with different scanning protocols can more effectively reduce the radiation dose than the routine CT scan mode for a kidney CTA while still maintaining diagnostic image quality, and protocol 2 of spectral imaging in our study is recommended.

Objective To investigate the feasibility of automatic spectral imaging protocol selection (ASIS) and adaptive statiatical iterative reconstruction (ASiR) technique to reduce radiation dose and dose of contrast agent.Methods Sixtyfour patients underwent routine abdominal examination were randomly divided into two groups.The test group used ASIS technique,with 30％ ASiR and 50％ ASiR reconstruction algorithm.The control group used 120 kVp tube voltage,FBP reconstruction method.The noise of liver,pancreas,sacrospinal muscle,CNR of liver and pancreas,subjective image score in arterial phase and portal venous phase were compared between the image of 70 keV+30％ ASIR and control group.CNR of abdominal aorta and its branchs,CNR of portal vein,and subjective image score were statistically analyzed between im age 55 keV+50％ ASiR and control group in the arterial phase and portal venous phase.Results Compared with control group,CT dose index volume for arterial phase and portal venous phase in test group decreased by 23.68％,23.57％ and dose length product decreased by 25.61％,18.45 ％,total contrast injection decreased 16.86 ％,the noise of liver,pancreas and sacrospinal muscle in 70 keV+30％ ASiR were lower than those of control group in abdominal arterial and portal phase (all P＜0.05).CNR of abdominal aorta,superior mesenteric artery,celiac axis and score in 55 keV+50％ ASiR were higher than those of control group in abdominal arterial phase (all P＜0.05),CNR of portal vein and score in portal phase had no statistically difference (all P＞ 0.05).Conclusion Combining of ASIS and ASiR including 70 keV + 30％ ASiR and 55 keV+50％ ASiR,images are superior to that of the conventional 120 kVp+FBP scan mode for abdominal CT image and vessel image quality,which can reduce the radiation dose and the dose of contrast agent.

In traditional Chinese medicine herbs (TCM), including Radix Salviae Miltiorrhizae (Danshen), Radix Puerariae Lobatae (Gegen), Radix Angelicae Sinensis (Danggui), and Rhizoma Chuanxiong (Chuanxiong) are widely used for the prevention and treatment of cardiovascular diseases and also often co-administered with Western drugs as a part of integrative medicine practice. Carboxylesterase 1 (CES1) plays a pivotal role in the metabolisms of pro-drugs. Since (S)-2-(2-(6-dimethylamino)-benzothiazole)-4,5-dihydro-thiazole-4-carboxylate (NLMe) has recently been identified by us as a selective CES1 bioluminescent sensor, we developed a rapid method using this substrate for the direct measurement of CES1 activity in rats. This bioluminescence assay was applied to determine CES1 activity in rat tissues after a two-week oral administration of each of the four herbs noted above. The results demonstrated the presence of CES1 enzyme in rat blood and all tested tissues with much higher enzyme activity in the blood, liver, kidney and heart than that in the small intestine, spleen, lung, pancreas, brain and stomach. In addition, the four herbs showed tissue-specific effects on rat CES1 expression. Based on the CES1 biodistribution and its changes after treatment in rats, the possibility that Danshen, Gegen and Danggui might alter CES1 ac-tivities in human blood and kidney should be considered. In summary, a selective and sensitive biolu-minescence assay was developed to rapidly evaluate CES1 activity and the effects of orally administered TCMs in rats.

Objective: To explore the relationship between different roles in campus bullying and depression among adolescents. Methods: Stratified cluster sampling method was used to select adolescents in grade 6-8 from three middle schools of Shanghai during November and December of 2017. Adolescents were surveyed anonymously using computer assisted self-interview approach via the tablets. Information including demographic characteristics, depression, and bullying was collected. The chi-square test and multivariate Logistic regressions were performed to explore the relationship between bullying roles and depression. Results: About 75.74% of the respondents were involved in bullying, including 456(27.65%) bystanders, 559(33.90%) victims, 33(2.00%) perpetrators, and 201 (12.19%) perpetrator-victims. There were 1 022(61.98%) respondents in the low depression group and 627 (38.02%) in the high depression group. Multivariate logistic regression showed that the four sub-groups involved in bullying all had higher level of depression than those uninvolved, with the perpetrator-victims (OR=4.77, 95%CI=3.27-6.96) and the victims (OR=3.66, 95%CI=2.71-4.94) had more depressive symptoms. Conclusion Different roles in campus bullying associates with more depressive symptoms, including perpetrators, victims, perpetrator-victims, and the bystanders.

Objective: To explore the relationship between Adverse childhood experiences(ACEs) and depression in early adolescence, and to provide scientific basis for effectively coping with the impact of ACEs on adolescents’ mental health. Methods: Stratified cluster sampling method was used to select adolescents in grade 6-8 in three middle schools of Shanghai during November and December of 2017. Adolescents were investigated anonymously using computer assisted self-interview approach via the tablets. Information including demographic characteristics, ACEs, and depression was collected. The chi-square test and multivariate logistic regression were used to explore the relationship between ACEs and depression, after controlling potential confounders. Results: Totally 1 629 eligible records were obtained. 65.25% of the respondents had experienced of neglect, followed by those abused(61.26%), and the incidence of family dysfunction was relatively low(20.81%). About 79.01% of the respondents had experienced at least one ACE, and more than half(61.45%) of the respondents had experienced at least two ACEs, and 10.01% of the respondents had experienced five or more ACEs. Multivariate logistic regression analysis showed that abuse and neglect experienced by male and female adolescents was associated with depression severity, with the OR values ranging from 2.62 to 3.60. Family dysfunction was found to be associated with depression only in male adolescents, with the OR of 1.91. The cumulative effect of ACE score on depression was observed. Conclusion Different types of ACEs in early adolescents are associated with depression, and ACEs have cumulative effects on depression severity.

Objective: To explore the relationship between body image and adverse childhood experiences (ACEs) in adolescents. Methods: A total of 1 701 adolescents in grade 6-8 in three middle schools in Shanghai were selected by stratified cluster sampling, and were investigated anonymously using computer assisted self interview approach. Information including demographic characteristics, body image satisfaction, and ACEs were collected. The Chi square test and multivariate Logistic regression were used to explore the relationship between adolescent body image satisfaction and types of ACEs. Results: About 60.73% of the respondents were satisfied with their body image, with higher satisfaction among boys(66.16%) than among girls(55.13%)( χ 2= 21.70 ， P <0.01). About 79.19% of the respondents had experienced at least one ACE, and respectively 61.61%, 65.14% and 21.58 % of them had experienced abuse, neglect and family dysfunction. Multivariate Logistic regression analysis indicated that experiencing at least one ACE, abuse, neglect and family dysfunction were all related with low body image satisfaction among girls( OR =0.33- 0.57 , P <0.01), while among boys neglect,having 3 or more than 4 ACEs were found to be associated with body image satisfaction ( OR =0.54-0.64, P <0.05). The cumulative effects of ACEs on adolescent body image were observed. Conclusion Different types of ACEs are associated with body image in adolescents, ACEs have cumulative effects on adolescent body image, which shows gender differences.Screen of ACEs and improvement of family nurturing environment should be highlighted among adolescents, especially among girls.

OBJECTIVE：To study the pr otective effect of schisandrin A （SA）on CCl 4-induced liver fibrosis model mice and its mechanism. METHODS ：Mice were randomly divided into blank control group ，model group ，silymarin group （positive control，100 mg/kg），SA low-dose and high-dose groups （20，40 mg/kg），with 10 mice in each group. Except for blank control group，other groups were given CCl 4 subcutaneously to induce liver fibrosis model. After successful modeling ，administration groups were given relevant medicine intragastrically ，once a day ，for consecutive 6 weeks；blank control group and model group were given constant volume of 0.5％sodium carboxymethyl cellulose solution intragastrically by the same way. HE staining was used to observe the pathological changes of liver tissue in mice. UV spectrophotometry and ELISA assay were adopted to detect the serum levels of liver injury indexes （ALT and AST ）and the contents of inflammatory factors （TNF-α，IL-1β，IL-6）. Western blotting assay was used to detect the expression of NOD like receptor protein 3（NLRP3）/NF-κB and TGF-β/Smad signaling pathway protein. RESULTS ：Compared with blank control group ，obvious pathological changes of liver fibrosis were observed in model group. The serum levels of liver injury indexes and contents of inflammatory factors were significantly increased （P＜0.01）. The expression of NLRP 3，apoptosis associated spot-like protein ，Caspase-1 and IL- 1β，TGF-β1 and ratios ofp-NF-κB p65/NF-κB p65，p-IκBα/IκBα，p-Samd3/Smad3 were increased significantly （P＜0.01）. Compared with model group ，SA could significantly relieve hepatic fibrosis in mice ，reduce serum levels of liver injury indexes and contents of inflammatory factors ，as well as the expression of NLRP 3/NF-κB and TGF-β/Smad signaling pathway protein and phosphorylation level（P＜0.01）. CONCLUSIONS ： SA can effectively relieve liver injury and inflammation of CCl 4-induced hepatic fibrosis model mice ，which may be through the regulation of NLRP 3/NF-κB and TGF-β/Smad3 signaling pathways ，thus inhibiting the process of liver fibrosis.